3rd Kuala Lumpur International Conference on Biomedical Engineering 2006

Electromuscular incapacitating devices (EMDs), such as Tasers, deliver high current, short duration pulses that cause muscular contractions and temporarily incapacitate the human subject. Some reports suggest that EMDs can kill. To help answer the question, “Can the EMD directly cause ventricular fibrillation (VF)?,” ten tests were conducted to measure the dart-to-heart distance that causes VF in anesthetized pigs (mass = 64 kg ± 6.67 (SD)) for the most common X26 Taser. The dart-to-heart distance that caused VF was 17 mm ± 6.48 (SD) for the first VF event and 13.7 mm ± 6.79 (SD) for the average of the successive VF events. The result shows that when the stimulation dart is close enough to the heart, X26 Taser current will directly trigger VF in pigs. Echocardiography of erect humans shows skin-to-heart distances from 10 to 57 mm (dart-to-heart distances of 1 to 48 mm). These results suggest that the probability of a dart on the body landing in 1 cm

2

over the ventricle and causing VF is 0.000172.

Neural engineering is an emerging discipline to understand the organizational principles and underlying mechanisms of the biology of neural systems and to study the behavior dynamics and complexity of neural systems in nature.

Nanotechnology is emerging as a new field enabling the creation and application of materials, devices, and systems at atomic and molecular levels and the exploitation of novel properties that emerge at the nanometer scale. Many areas of biomedical engineering are expected to benefit from nanotechnology including sensors for use in the laboratory, the clinic, and within the human body, new formulations and routes for drug delivery, and biocompatible, high-performance materials for use in implants. Examples of potential uses of nanotechnology in biomedical engineering include the early detection and treatment of disease. Recently, enormous researchers with this notice have been launched to encourage the applications for research, in the general areas of nanoscience and nanotechnology as related to

1)

The development of new research tools for elucidating biological principles essential for the design and implementation of nanostructured materials for use in biomedical engineering, and

2)

The transfer of nanotechnology advances in other fields of science and engineering to develop new ways to help prevent, detect, diagnose, and treat disease and disorders.

Nanostructures offer a new paradigm for materials manufacture by submicron-scale assembly (ideally, utilizing self-organization and self-assembly) to create entities from the “bottom up” rather than the “top down” ultraminiaturization method of chiseling smaller structures from larger ones. Each significant advance in understanding the physical/chemical bio properties and fabrication principles, as well as in development of predictive methods to control them, is likely to lead to major advances in our ability to design, fabricate and assemble the nanostructures and nonodevice into a working system being applicable to healthcare technology.

Objectives: To develop 3-D nasopharyngeal airways from 2-D acoustic rhinometer data for diagnostic purposes. Methods: Rhinometer readings were taken from 285 Malaysian subjects. Data from the right (R) and left (L) nostrils were stratified according to age and sex. The sample comprised: 88 Female Teenagers (FT); 77 Female Adults (FA); 70 Male Teenagers (MT), and 50 Male Adults (MA). New algorithms were developed and encoded in C++ using Air-Ex3™ software. Mean 3-D left and right nasopharyngeal airways were computed for each group, and subjected to finite-element scaling analysis and principal components analysis, using statistical tests for dependent groups. Results: Comparing the corresponding 3-D mean left nasopharyngeal airway with the right side for all four groups, no statistical differences were found. When comparing left sides by age and sex, however, significant differences were detected for the following groups: MAL vs. FTL, MAL vs. FAL, MAL vs. MTL, MTL vs. FTL (p < 0.05). Similarly, for the right side, significant differences were detected for the following groups: MAR vs. FTR, MAR vs. FAR, MAR vs. MTR (p < 0.05), but MTR was not significantly different from FTR. Therefore, the adult Malay male 3-D nasopharyngeal airway differs from females (both teenagers and adults) and teenage males, bilaterally. Specifically, the adult Malay male nasopharyngeal airway is narrower in the anterior nasal valve region closer to the nostril and wider in the distal regions of the 3-D nasopharyngeal airway. Conclusions: This protocol may useful for the diagnosis, treatment planning and assessment of nasopharyngeal conditions, such as snoring, sleep disordered breathing and obstructive sleep apnea. As well, a similar methodology can be applied to 2-D acoustic pharyngometry data.

A hierarchical multi-layer neural network with an error back-propagation training algorithm has been adopted for the automatic classification of Giemsa-stained human chromo-somes. The first step classifies chromosomes data into 7 major groups based on their morphological features such as relative length, relative area, centromeric index, and 80 density profiles. The second step classifies these 7 major groups into 24 sub-groups using each group classifier. The classification error decreased by using two steps of classification and the classify-cation error was 5.9%. The result of this study shows that a hierarchical multi-layer neural network can be accepted as an automatic human chromosome classifier.

In recent years, there have been intensive investigations on various microfluidic devices and integrated microfluidic systems, such as lab-on-a-chips (or micro total analysis system—

μ

-TAS) and microreactors. They have been increasingly applied for the biological and medical processes such as genetic analysis, disease diagnosis, chemical synthesis, etc. One involved problem is to mix fluids at microscopic scales. Due to the reduced feature size, the micro flow is usually viscosity dominant laminar flow, and the fluid mixing is limited to diffusion. However, in many applications, the fluid mixing is of crucial importance. The mixing efficiency may directly affect the performance of the whole system. In this paper, the techniques to enhance fluid micromixing are reviewed. A brief introduction of their applications for various biological and medical processes is also presented.

The role of telemetry and communications technology will be explored in a number of medical devices developed at the Graduate School of Biomedical Engineering, University of New South Wales. Topics discussed will include clinical measurement devices used for home telecare, triaxial acceleromters for personal alarming in the elderly, implantable heart pumps and vision prostheses.

In particular, a review of the state-of-art with regards vision neuroprostheses, with an emphasis on retinal prostheses, will be presented. Through an examination of the neurobiology and biophysics at the electrode tissue interface and by drawing heavily on biologically-inspired designs, critical areas that require concentrated research and development will be described. Brieflycovered are topics relating to application specific integrated circuits (ASIC), appropriate image processing for prosthetic vision, the psychophysics of prosthetic vision, and models of parallel stimulation at multiple electrode sites.

The majority of currently used implant materials in orthopaedics lacks osteoconductivity. This paper reviews our efforts of using a number of surface modification techniques (hydrothermal-electrochemical deposition, plasma spraying, spraying-and-sintering, ion beam assisted deposition, and biomimetic deposition) to improve the osteoconductivity of metallic, polymeric and ceramic biomaterials. Furthermore, biomimetic processes have been employed to render non-bioactive polymer tissue engineering scaffolds osteoconductive. Surface modification has an important role to play in the development of materials for human tissue repair and regeneration.

Navigation for neurosurgical procedures must be highly accurate. Often small structures are hardly seen on pre-operative scans. Fitting a 3D electronic neuro-anatomical atlas on the data assists with the localization of small structures and dim outlines. During surgery also brainshifts occurs. With intra-operative MRI the pre-operative MRI can be warped to the real 3D situation. The paper describes a general 3D landmark-based warping method, based on radial basis functions (thin plate splines) for data of any number of dimensions, including all code in

Mathematica

.

This study was performed to evaluate the characteristics of the spectral peak intensities and T2-relaxation times of the biochemical metabolites related to cancerous gastric tissue using ex vivo proton MR spectroscopy (

1

H MRS) method, and to assess its clinical usefulness. The volume of interest data results from MRS measurement was extracted from proper muscle (MUS) layer and the composite mucosa/submucosa (MC/SMC) layer and their spectral peak intensities and T2-value were quantitatively analyzed. In this study, we present that both of spectral peak analysis and T2-relaxation time measurement using MRS method may be very useful for the diagnosis of the gastric cancer.

This paper describes the comparison between Principal component analysis (PCA) also known as eigenfaces and Zernike moments (ZM) as feature extractors, used in face recognition. These feature extraction methods are still being research until today even though the techniques may either be hybrid or fusion. The study look into the capability of these two feature extraction methods to recognize face due to changes in illumination condition, pose, facial expression and others. The experiment carried out utilizes the earliest eigenfaces technique adopted from Turk and Pentland [1] and ZM polynomials [2]. The classification technique employed in the recognition stage is a simple Euclidean square distance classifier or nearest neighbor (NN). The experiments utilized database face images from Olivetti research laboratory (ORL) consisting of 40 subjects of 10 images each where none of them are identical [3]. They vary in position, rotation, scale and expression, with and without glasses. From the comparative study, the outstanding feature extraction method is considered for face recognition system.

Accurate estimation of fetal weight is crucial for deciding which mode is the best for babies to be delivered. With the advancement of ultrasonic technologies, sonographic parameters of the fetal can be used to estimate fetal weight. Fetal weight estimated by regression methods is relatively acceptable in the clinical Obstetrics, but the accuracy of estimated fetal weight remains to be improved. This study was aimed to develop a group-based artificial neural network model to improve the accuracy of fetal weight estimation through sonographic parameters. Stepwise regression analysis was used to examine and extract the significant parameters. The input layer in the artificial neural network model included seven significant parameters such as biparietal diameter, occipito-frontal diameter, abdominal circumference, gestational age, femur length, gender, and fetal presentation. A total of 2,107 consecutive singleton fetuses were divided into training group with 1,411 samples and testing group with 696 samples. The results show that the accuracy of fetal weight estimated by the artificial neural network model is significantly better than those by regression methods. The importance of this study is to consider and control the heterogeneity among the high variability and broad ranged parameters by statistics, and to choose scientific parameters as reasonable input variables of artificial neural network to improve the estimation of fetal weight. This study has proved the accuracy of fetal weight estimation by artificial neural network model is better than those of previous models.

This paper presents a study on classification of breast lesions using artificial neural networks. Thirteen morphological features have been extracted from breast lesion cells and used as the neural network inputs for the classification. Multilayered Perceptron, Radial Basis Function and Hybrid Multilayered Perceptron networks were used to perform the classification task. Unlike the previous studies that only classify the lesion into benign and malignant, this study extends the breast lesions classification into four categories that are malignant, fibroadenoma, fibrocystic disease and other benign cells. The three neural networks were trained and compared using 1300 data samples. The classification results indicating that all the networks give good overall diagnostic performance. However, only Hybrid Multilayered Network that provides 100% accuracy, sensitivity and specificity.

This paper describes the development of a rule based expert system to classify risk in dengue infections using bioelectrical impedance analysis (BIA). This system is able to classify three types of risk groups in dengue infections; higher risk, lower risk and no risk (healthy) groups. The classification process was done according to gender, reactance value of the BIA and ‘day of fever’ on a daily basis diagnosis. BIA measurements have been conducted on 209 serological confirmed dengue patients during their hospitalisation in University Kebangsaan Malaysia Hospital (HUKM), and 223 healthy subjects in Malaysia. The rules were developed based on the 95% confidence interval ranges of reactance value for each risk group obtained from the univariate analysis of variance (ANOVA) analysis. The system was designed and programmed via Visual Basic 6.0. Graphical user interface were employed, in order to enhance user interaction with the system. The system is able to classify the risk in dengue patients noninvasively with total classification accuracy of 66.7%.

One of the most dangerous symptoms of Type 1 diabetes is the frequent and grate oscillation of blood glucose level that can lead the patient to unconscious and coma states. So being able to predict and finally prevent these two symptoms would simplify the management of the diabetic patients. This paper attempts to comparison the performance of MLP and Elman neural networks to predict the blood glucose levels in type1 diabetics. Data set, used in this paper consists of the protocol of a 10 Iranian type1 Diabetic women and include features such as type and dosage of injected insulin, The period of time (in hour) between two consecutive measurements of the blood glucose level, carbohydrate intake, exercise and the blood glucose level measured at start of the given period of time. Finally we concluded that the usage of Recurrent Neural Network such as Elman can be an appropriate model to predict the long term blood glucose level in type 1 diabetics also we could successfully increase the accuracy of prediction and reduce the number of layers and neurons used in the construction of Neural Networks.

The method is used to register the laryngeal behavior indirectly by measuring change in the electrical impedance across the throat during speak or voice. The RF carrier signal is amplitude modulated by the modulating speech/ voice signal and the dc component from the demodulated signal is extracted. The variations in the dc component corresponds to the vocal fold abduction/laryngeal movement. For normal and pathology conditions the results are recorded. These values form a feature vector which reveal information regarding pathology. Then a classical multilayer feed forward neural network with back propagation algorithm is employed to serve as a classifier of the feature vector, giving 100% successful results for the specific data set considered.

This paper describes the development of a Rule Based Expert System (ES) to classify the Total Cholesterol (TC) level using Bioelectrical Impedance Analysis (BIA). A total of 199 voluntary subjects were recruited in the study. The BIA parameters that are statistically significant predictors are body capacitance (BC), basal metabolic rate (BMR) extracellular mass (ECM) and lean body mass (LBM). The ES was developed using Bayesian reasoning method. The developed ES is able to classify subjects’ TC level between normal (<=5.2 mmol/L) and abnormal (>5.2 mmol/L). From the analysis using 40 testing data, the system total accuracy for classifying TC level at 0.6 probability cutoff prediction was only 70.0%. The sensitivity was 67%, and specificity of 74%. From the validation data, this ES system can classify 6 from 10 subjects correctly.

The eye feature plays a vital role in classifying the face emotion using Genetic Algorithm. The acquired images have gone through few preprocessing methods such as grayscale, histogram equalization and filtering. Among the edge detection methods, Sobel method performed very well in segmenting the image. The projection profile is found to be suitable feature extraction method comparing with other two methods in respect of time of processing. The second part discusses a Genetic Algorithm methodology of estimating the emotions from eye feature alone. Observation of various emotions lead to a unique characteristic of eye, that is, the eye exhibits ellipses of different parameters in each emotion. Genetic Algorithm is adopted to optimize the ellipse characteristics of the eye features. A new form of fitness function is proposed for the Genetic Algorithm. It is ensured through several experiments that the optimized parameters of ellipse reveal various emotional characteristics. Processing time for Genetic Algorithm varies for each emotion.

This paper presents a procedure of frame normalization based on the traditional dynamic time warping (DTW) using the LPC coefficients. The redefined method is called as the DTW frame-fixing method (DTW-FF), it works by normalizing the word frames of the input against the reference frames. The enthusiasm to this study is due to neural network limitation that entails a fix number of input nodes for when processing multiple inputs in parallel. Due to this problem, this research is initiated to reduce the amount of computation and complexity in a neural network by reducing the number of inputs into the network. In this study, dynamic warping process is used, in which local distance scores of the warping path are fixed and collected so that their scores are of equal number of frames. Also studied in this paper is the consideration of pitch as a contributing feature to the speech recognition. Results showed a good performance and improvement when using pitch along with DTW-FF feature. The convergence rate between using the steepest gradient descent is also compared to another method namely conjugate gradient method. Convergence rate is also improved when conjugate gradient method is introduced in the backpropagation algorithm.

In this paper, a computational model has been developed to identify a face of an unknown person’s by utilizing eigenfaces as unique features and backpropagation Neural Network for recognition. The features of a basic human face are extracted using eigenfaces. These features are then used to identify an unknown face by using multiple numbers of backpropagation neural networks. Samples of 15 human faces are obtained from The ORL database. The experiments are compared to the effects of changes size of face images, different face images combination and different neural network parameter. The classification more than 90% for trained classes and 18% for untrained classes were achieved.

The purpose of the study was to recognize EMG signal patterns of lower limb muscles by using neural networks during the recovery of postural balance of human body. Surface electrodes were attached to several lower limb muscles. EMG signals were collected during the postural balance recovery process after a perturbation without permitting compensatory stepping. A waist pulling system was used to apply transient perturbations in five horizontal directions. The EMG signals of fifty repetitions of five motions were analyzed for 10 subjects. Twenty features were extracted from EMG signals of one event. By using neural networks, EMG signals were classified into five categories, such as forward perturbation, backward perturbation, lateral perturbation and two oblique perturbations. As results, motions were recognized with mean success rates of 75 percent. With the neural network classifier of this study, the EMG patterns of lower limb muscles during the recovery of postural balance could be classified with high accuracy of recognition.

Over the past two decades, there has been concern about potential adverse effects of EMF radiations on humans due to widespread use of electrical appliances. Reports have shown sufficient scientific evidence regarding the impact of electromagnetic field on the human health. This paper aims at reviewing the EMF effects particularly in higher education engineering laboratories. Several relevant methods on estimating EMF radiation has been studied and analyzed.

Previous studies have shown that repetitive transcranial magnetic stimulation (rTMS) can modify cortical excitability in humans, and particularly that a recentlyproposed rTMS protocol, “theta burst stimulation” (TBS) can induce the long-lasting effects with the stimulation duration much shorter than those of conventional rTMS protocols. However, in those studies, the effects of rTMS were assessed mainly by means of motor evoked potential, and how the rTMS affects functional coupling between cortex and muscle was least studied. Here, we examined the coherence between electroencephalographic (EEG) and electromyographic (EMG) signals during isometric hand (first dorsal interosseous muscle) contraction, before and after application of TBS to primary motor area (PMA). Magnitude of the EEG-EMG coherence at beta band (13–30Hz), localizing for the C3 scalp site, significantly decreased 30–60 minutes after TBS and, in 90–120 minutes, gradually recovered to the control level before TBS. The present results suggested that TBS applied to PMA can suppress the cortico-muscular synchronization.

Chitoan, which is derived from chitin, is a linear heteropolysaccharide composed of β-1,4-linked D-glusosamine (GlcN) and N-acetyl-D-glucosamine (GlcNAc) with various compositions of these two monomers. The degree of acetylation (DA) represents the portion of GlcNAc units to total number of units. DA of chitosan influences not only the physicochemical characteristics, but also the biodegradability and biocompatibility. We synthesized DA-controlled chitosans (from 10% to 90%) by the acetylation reaction of deacetylated chitosan (DA ∼ 10%) and acetic anhydride with different ratio. The DA value of the chitosans was characterized by solid state 13C NMR and FT-IR spectroscopies. Surface properties of chitosan films with different DA value were investigated by the measurements of water contact angle and Zeta potential. The cell compatibility of the acetylated chitosans was estimated by cell culture using NIH/3T3 mouse fibroblasts and C28/I2 human chondrocytes. It was observed that the cell adhesion and growth decreased on the acetylated chitosan film surfaces with increasing DA value, probably owing to the increased number of acetyl groups leading to the increased hydrophobicity and reduced positive charge on the film surfaces. The degradation behavior of the acetylated chitosan films was also investigated in the solutions of lysozyme and/or N-acetyl-β-D-glucosaminidase, which are enzymes for chitosan existed in the human body. The degradation rate of the films with different DA value was observed as follows: 50 % > 30 % ≈ 70 % > 90 % > 10 %. Modifying the DA of chitosan provides a powerful means for controlling biodegradation and biocompatibility and can be optimized for tissue engineering applications.

Generally, inflammatory response to the metal stents contributes to the formation of in-stent restenosis. Howerver, recent development of biodegradable stents made of magnesium alloys has a potential to overcome this drawback. Nevertheless, the degradation profile of such stents and the influence on the endothelial cells remained unclear.

In this study, the flat magnesium alloyed sheets cut by wire electrical discharge machine were immersed in distill water or culture medium. In addition, human aortic endothelial cells (HAEC) were seeded (800 cells/mm

2

) onto various magnesium alloyed sheets, including Mg-Al-Zn alloys (AZ31, AZ91) and Mg-Al-Mn alloy (AM60). Cells seeded onto tissue culture treated polystyrene dish coated with gelatin were used as controls. Forty-eight hours later, the cells were examined by immunofluorescence microscopy.

The results were shown that content of Mg

2+

within 15 weeks gradually increased to more than 40 mg/dL in the culture medium, but remained less than 10 mg/dL in the water. For all magnesium groups the cellularity at 48 hours was less than 60% of that of the controls (p<0.01). Comparison among the magnesium alloyed groups showed that both AZ31 and AM60 have lower values of cellularity, compared to the AZ91 (AZ31: 164 cells/mm

2

; AM60: 318 cells/mm

2

; AZ91: 442 cells/mm

2

; AZ91 vs either AZ31 or AM60, both p<0.05). Immunfluorescence microscopy showed that cells grown on such magnesium metals expressed less amounts of Von Willebrand factor (VWF), connexin43 (Cx43) gap junctions, and endothelial nitric oxide synthase (eNOS).

The conclusion suggested that degradation of magnesium alloys are enhanced in culture medium, in which HAEC’s had a retarded growth and protein expression profile grown on the metal. Otherwise, it also suggested that strategies to improve the biocompatibility of stents made of magnesium alloy are necessary.

This paper focuses on the usage of a novel binder system base on palm oil product to produce sintered parts of stainless steel 316L produced by vertical injection molding technique for biomedical application. The stainless steel 316L powder was mixed using z-blade mixer with the thermoplastic binder system comprising of polyethylene, paraffin wax, stearic acid and palm stearin which was derived from palm oil at different volume percent (%). The feedstock then was studied in term of viscosity and shear rate using capillary rheometer. The feedstock was molded using vertical injection molding machine. After molding, the green molded part was immersed into the solvent to extract part of the binder system followed by sintering under vacuum atmosphere at the temperature of 1360°C. The physical and mechanical properties of the sintered part such as density, hardness, shrinkage, ultimate tensile strength and elongation were measured. Biocompatibility study of

in vitro

test using cell osteosarcoma MG-63 was observed and discussed.

The extensive use of appropriate coatings to improve wear resistance, friction coefficient, electrical properties, corrosion resistance and biomedical application has stimulated a growing interest in their mechanical properties and especially hardness testing that is routinely used for coating evaluation. In this study Jönsson and Hogmark model is applied for the porous hydroxyapatite produced by plasma spraying on Ti6A14V substrate. Firstly, the effect of indentation load on hardness values of coating and substrate are studied. The modified Jönsson and Hogmark model is used to explain the composite hardness behavior and the effect of coating porosity.

This study focused on the effect of surface-modification of 3D poly(L-lactic acid) (PLLA) scaffolds in the formation of hydroxyapatite (HA) crystals in simulated body fluid (SBF). PLLA scaffolds were subjected to plasma treatment and simultaneous grafting of acrylic acid (AA). When three different substrates, such as PLLA control, PLLA-HA, and PLLA-PAA-HA were analyzed, HA crystals on the surface of AA-grafted PLLA were identified better in size and distribution. The major compositions of HA, calcium and phosphorus were confirmed in the ESCA analysis of PLLA-PAA-HA. Significantly reduced water contact angles were identified with PLLAHA and PLLA-PAA-HA as compared to PLLA control. When osteoblasts were cultivated in different 3D PLLA scaffolds, good cell attachment was seen from scanning electron microscopy (SEM) micrographs and osteoblasts appeared to be well spread and aggregated on the HA-formed scaffold. Once the total cell number was determined, the highest cellularity was noted with the PLLA-PAA-HA during 4-week culture. The difference was statistically significant between PLLA-PAA-HA and PLLA control or PLLA-HA. This study indicates that functional carboxylic groups could greatly facilitate HA crystal formation and that HA-formed polymer scaffolds can find favorable applications in bone tissue engineering.

Local antibiotic-loaded beads have been approved for standard treatment of orthopaedic pathogens, especially chronic osteomyelitis. Septopal®, the only commercial local antibiotic bead available on the market, is expensive and contains only gentamicin. This study aimed to compare the

in vitro

inhibitive effect of hand-made antibioticloaded beads (fosfomycin-sodium) with Septopal® for ten bacterial strains of chronic osteomyelitis by diffussion technique at various indicated time points. The results showed that Septopal® could inhibit all bacterial strains except CNS 7334 and CNS 7391. Hand-made fosfomycin beads were only slightly effective in two of the ten bacterial strains is used (

Staphylococcus aureus

7323 and CNS 7391). In conclusion, this study demonstrated that Septopal® can inhibit common orthopaedic pathogens better than hand-made beads

in vitro

study, however, fosfomycin concentrations required to kill orthopedic implant related bacterial strains are high and its release from hand-made beads is too low to be considered efective when compared with Septopal beads.

The mineral component of bone is a form of calcium phosphate known as hydroxyapatite. Due to the presence of significant amount of foreign ions, biological apatites have a poor crystallinity and are non-stochiometric. Size and shape of mineral particles change with species, age, and disease. This work studied the relationship between rat bone mineral and the age of rat. Analysis was carried out by using an X-ray diffraction (XRD) and a scanning electron microscopy (SEM). It was found that bone apatite has a nano sized crystal (14, 70 – 24,49 nm). Bone apatite crystalinity has a nonlinear relation to the age, however younger rats is more crystalline than older. SEM micrograph has shown that bone apatite, which is a nanostructure material, composes two phase, amorphous and crystalline.

Bone healing is one of the importance phenomena in various clinical fields. The rapid appearance of fibrous connective tissue in bone defect during the healing, which can lead to the incomplete bone formation, has been considered as a major problem. To solve this, guided bone regeneration (GBR) membranes which can prevent fibrous connective tissue infiltration and thus promote bone healing have been used as a simple therapy. In this study, we fabricated a novel GBR membrane by the immersion precipitation of PCL/Tween 80 electrospun sheet filled with PLGA/Pluronic F127 solution. The top surface of prepared membrane had nano-size pores (∼100 nm) which can effectively prevent from fibrous connective tissue invasion but permeate nutrients, while the bottom surface had micro-size pores (∼ 40 µm) which can improve adhesiveness with bone and provide osteoconductivity. The morphology, mechanical (tensile and suturing) strengths and model nutrient permeability of the prepared membrane and its bone regeneration behavior using a rat model (skull bone defect) were compared with those of PLGA/F127 membrane, PCL/Tween 80 electrospun sheet, and a commercialized GBR membrane, Bio-Gide®. From the result, the PCL electrospun sheet-embedded PLGA membrane (hybrid membrane) seems to be a good candidate as a GBR membrane for the effective permeation of nutrients and osteoconductivtity as well as the good mechanical strength to maintain a secluded space for the bone regeneration.

Surface modifications play a significant role in the interaction and success of implants to adjacent tissues. This study evaluated the surface topography and in vitro cellular response of surface treatments on titanium performed by multiphase anodic spark deposition (ASD). The titanium surfaces examined were: BioSpark (BS) and OsseoSpark (OS), obtained by ASD method; BioRough™ (BR), a chemical etching treatment used for comparison; and commercially-pure grade-2 titanium (cpTi) used as a control. The samples were cut in discs (12 mm diameter; 0.5 mm thickness) and sterilised by λ-irradiation prior to use. All samples were imaged using Scanning Electron Microscopy (SEM) (Hitachi S-3500N, Hitachi High-Technologies) to characterise the surface in 2 dimensions. Atomic Force Microscopy (AFM) (Topometrix Explorer SPM, Veeco Metrology LLC, CA, USA) was performed in contact mode to investigate topography in 3 dimensions and qualitatively analyse the surface roughness. Physicochemical analysis was also performed using energy dispersive X-ray spectroscopy (EDS) (Oxford Instruments Microanalysis, UK). A human osteosarcoma cell line (HOS TE85) was used for in vitro analysis; MTT assay to determine cell metabolic activity and Alamar Blue™ (Serotec) for assessing cell proliferation. SEM images indicated that ASD treatment created a microrough surface with a web-like nanostructure. AFM images illustrated the 3-dimensional topographies and quantitatively analysed surface roughness by ranging from the roughest to the smoothest which were Br > OS > BS > cpTi, respectively. Cellular response results showed no toxic leachables released from the test samples, thus indicating all sample were biocompatible. A good level of cell proliferation compared to the control was observed indicating a favourable attachment surface. This study has indicated that the ASD treatment surface has a nanostructure topography favouring cell attachment and proliferation and can potentially be used to improve titanium performance by enhancing osseointegration for use in dental implantology.

PLGA (75:25)/hydroxyapatite (HA) composite films were fabricated by solvent-casting method to investigate the effect of various hydroxyapatite content ratio to the PLGA for mechanical properties, cellular attachment and proliferation. Mechanical property of the composite film was characterized by tensile test. The ultimate tensile strength of 10 wt% HA content film was two-fold higher than control group. Surface of the film was characterized by contact angle measurement and scanning electron microscope (SEM). The PLGA/HA composites were more hydrophilic than control. Chondrocyte responses to the composite films were measured

in vitro

by cellular attachment and proliferation test. The attached and proliferated cells were significantly higher on PLGA/HA (10 wt%) composite film than control group (1.44 times higher in attachment test and 1.31 times higher for 6

th

-day at culture in proliferation assaying, p<0.05).

This article focuses on the physical characterization of Silverfil® amalgam. Analysis of the amalgamated material semi-quantitatively showed that Silverfil® comprised of approximately two thirds mercury and one third silver. No other elements were detected. Examination of the amalgamated material by x ray mapping and metallographically showed no evidence of free mercury present. Silverfil® has strong affinity towards the mercury ion. X-ray Diffraction analysis showed that the amalgamated Silverfil® is similar to a mineral in nature called “Moschellandsbergite”. The advantages of Silverfil® over conventional amalgam were highlighted.

The effect of cold isostatic pressing (CIP) on the sinterability of synthesized hydroxyapatite (HA) powder was investigated. The starting powder was initially uniaxially die-pressed at about 1.3–2.5MPa to form disk and rectangular green compacts. Two batches of green samples were prepared, i.e. one batch was in the as-compacted state (Un-CIP) and another batch samples was subjected to cold isostatic press at 200 MPa (CIP). The latter samples exhibited a linear shrinkage of ∼16% prior to sintering. All the samples were sintered in air at temperatures ranging from 700°C to 1400°C. The densification behaviour of HA was evaluated in terms of linear shrinkage, phase stability, bulk density, Vickers hardness and Young’s modulus. The results revealed that green samples subjected to cold isostatic pressing exhibited better sinterability and possessed excellent mechanical properties. This effect is more pronounced particularly for the low temperature sintering regime i.e. ≤ 1100°C.

The purpose of this study was to investigate the light intensity of selected light curing unit with varying distance and angulation of the light curing tip and lightmeter.

Four types of light units; Spectrum 800 (Dentsply), Coltulux 3 (Coltene), Elipar FreeLight 2 (3M Espe) and Starlight Pro (Mectron) were evaluated for light intensity at various distance between the light curing tip and the lightometer Cure Rite Denstply (0, 1, 3, 5, 10 and 15 mm). The light curing units were angulated at 45°, 60° and 90° at a standardized 5 mm distance.

The intensity of light curing is affected by the distance between the light curing tip and the lightmeter. However, the decrease in light intensity of the light curing unit was found not to obey the inverse square law for the distances 0 to 15 mm.

The study found that there was no significant difference between 45° and 60° angulation between the light curing tip and the lightmeter. However, the decrease in light intensity is significant when compared to the light tip is placed perpendicular (90°) to the aperture of the light meter.

Compositions of solid solutions xAg1-(1−x)ZnI

2

(0.5 ≤x ≤ 1), had been synthesized. The characterization studies of the materials using x-ray diffraction at room temperature and conductivity measurements by using impedance spectroscopy. The investigations were carried out for determination of the structure of materials and the conductivity for different composition in order to establish the relationship between the material structure and the conductivity. Samples with more AgI content are more crystalline. The conductivity of the compound will be increased with the decreases of crystalline structures.

Nanocrystalline hydroxyapatite (HAP) powder was synthesized by a non-alkoxide sol-gel method. The prepared powder was characterized with STA, X-ray diffraction, Zetasizer and SEM microscopy. The effect of aging for 24h and heating time at 550°C on crystallity, crystallite and particle size were studied through XRD, zetasizer and SEM. Results showed that the powder obtained after heating at 550°Cfor 6h was composed of pure HAP with the estimated crystallite size and particle size of 9.3 nm and 503.6 nm.

The production of hydroxyapatite (HA) from bovine bones was studied in this paper. Bovine hydroxyapatite (BHA) was produced from bovine bone powders by calcination without compaction. The powders were calcined at temperatures ranging from 700–1100°C. It was discovered that sample preparation has some influence on the calcination behavior of the bovine bone powders. XRD results confirmed that HA has been successfully produced but traces of α-TCP and β-TCP were also found. The Ca/P ratios of the BHA powders produced from the process have values greater than 2.0.

A novel injectable male contraceptive (RISUG®: an acronym for Reversible Inhibition of Sperm Under Guidance) has been developed by our research group and is currently in the advanced clinical trial stage. RISUG® consists of a copolymer styrene maleic anhydride dissolved in dimethyl sulfoxide of a particular formulation and is injected into the lumen of the vas deferens using a no-scalpel approach. Its polyelectrolytic nature induces a surface charge imbalance on the sperm membrane system leading to the leakage of enzymes essential for sperm-egg interaction. In the present study, surface characterization of the contraceptive using atomic force microscopy (AFM) is proposed. RISUG® gel was spin coated on glass sides and hydrolyzed with saline and seminal plasma to mimic

in vivo

conditions. Contact mode atomic force microscopy (AFM) has been used to analyze quantitatively the micro-structural properties of RISUG® and its precipitate in various systems. Hydrolysis of the contraceptive gel resulted in the formation of pores of varying dimensions. RISUG® being a highly charged molecule, as evident from zeta potential measurements, has a tendency to form a complex with ionic biomolecules present in the seminal plasma. This is supported by the experimental observations using AFM. This RISUG® - biomolecule complex possibly acts as an ionic trap for spermatozoa passing through the vas deferens. Micro-structural properties of RISUG® including amplitude (root mean square, peak-to-valley distance, skewness, and kurtosis) and spatial roughness have been studied to understand its response to various physiological conditions.

It has been recognised that compressive, tensile and flexural strength do not accurately determine the durability of dental restorations and that fatigue induced failure plays an important role. Fatigue caused by cyclic loading is thought to be responsible for the failure of composites restorations described by chipping, localized or generalized wear and fracture. The main aim of this work is to develop and evaluate the rolling ball contact as a method for testing surface fatigue of resin-based restorative materials. The results showed that material loss during the testing period mimic that of a fatigue failure process occurring in rolling elements. The rolling ball contact method proved to be a simple and reproducible method for testing fatigue in dental composites.

The study discusses a model for impact forces produced during landing from a jumping smash activity. The objectives are to investigate the magnitude of the forces during landing, to observe the angles at the hip and knee joints, as well as the forces in the horizontal axis. The Newton-Euler equation is applied to develop a model that represents the lower limb of a human body. World class badminton player are chosen as subjects during the Kuala Lumpur Thomas Cup 2000. Results show that during landing, the impact forces produced on the landing foot is lower than that of the other foot. Change of the angles on the shank and hip segments shows that subjects flexed their feet when landing to minimize injury.

Standing frame is commonly used in rehabilitation training for children with cerebral palsy (CP), but the design and clinical effectiveness were rarely investigated. In this study we modified the standing frame with adjusted footplate with a separate control, a linear acurator, high-density durable foam and adjusted table surface with Acme lead screew and sliding block. Six spastic quadriplegic CP children (aged 4.6±1.3y/o) were recruited and received electromyographic (EMG) evaluation on using both the traditional and modified standing frame for 15 minutes, with a two-week interval. A questionnaire was obtained after the evaluations.

EMG studies showed significantly lowered activities of bilateral anterior tibialis and gastrocnemius after using the modified standing frame for 6 to 15 minutes. The questionnaire also showed significant increased adjustment and satisfaction index with the modified frame. This modification reduces spasticity and muscle tone in CP children and helps to enhance the efficacy of rehabilitation program.

This study investigated the changes in Ground Reaction Forces, GRFs and trunk inclination among primary students when carrying heavy backpacks. A randomised controlled experimental study was conducted on seven boys aged between 9 and 11 years old with similar Body Mass Index. Observations were done when the boys were carrying school bags of 0 (as control), 10, 15 and 20% of their own body weight whilst normal walking. Data acquisition was carried out using force platforms and 3-D motion analysis system. A significant difference in Ground Reaction Forces at load of 20% of body weight was found. The vertical GRF increased almost three times when loads increased up to 20% of body weight compared to 10% of body weight. The anterior-posterior GRFs were asymmetrical when loads were increased. When carrying load of 15% of body weight, the subjects adopted a compensatory trunk inclination. If Ground Reaction Forces and trunk inclination are important as the criteria to determine the acceptable backpack loads for children, those loads should not exceed 15% of body weight.

A preliminary study is conducted to investigate the effect of task activity on Biceps brachii muscles response during repetitive task at automotive industry in Malaysia. The aim of the study is to analyze time to fatigue of bicep brachii muscles during repetitive task at a tyre assembly in an automotive industry. Thirty electromyography (EMG) measurements were taken from three selected samples at the tyre assembly line. Measurements were taken in duration of two hours and thirty minutes. The results indicate that similar root-mean-square (RMS) patterns were obtained for the three samples. Regression method was used for the analysis. In addition, the regression analysis also gives similar prediction on the subject. One explanation is that time to fatigue for a particular task can be predicted.

Urinary catheter has been widely used as a solution for urinary incontinence problem. But it can induce pressure stress at the human bladder neck. However, owing to the complexities in balloon geometries, material properties and interactions in bladder, analyses of the complete stress inflation of balloon are limited. This study describes some numerical simulations of the expansion phase of catheter balloon on bladder and to study the stress distribution at the balloon. In order to investigate the mechanical characteristics of inflation catheter balloon, a three-dimensional model of the complete catheter balloon were developed, which made the simulation well close to the real situation. Finite element analysis (FEA) ABAQUS 6.4-PR11 was used to simulate the balloon inflation and deflation. The hyperelastic behavior of the Mooney-Rivlin model is considered. Mechanical properties of the balloon have been taken from the literature. Simulated results showed that the stress distributed on the surface of the balloon. The maximum Von Mises stress for natural rubber from the analysis is 5.11 MPa. High stress concentrates on the center of it. In conclusion, FEM can help illustrate and quantify some mechanical characteristics of the balloon and it would be helpful for the general understanding of inflation of urinary catheter balloon.

Expansion of the maxilla is used to correct skeletal and dental transverse discrepancies between the maxilla and mandible. These discrepancies are corrected through a combination of skeletal expansion (separation of the maxillary midpalatal suture) and dental expansion (lateral tipping of the maxillary posterior teeth). The rapid maxillary expansion appliance is a tooth-borne appliance that consists of a midpalatal jackscrew. Appliances currently on the market for expanding the maxillary dentition vary from simple tooth tipping devices to rigid orthopedics expanders. These devices vary widely from active implants with springs and/or screw, to passive acrylic molds and simple medical tape. The problem with current devices is they need to be manipulating manually multiple times to readjust the screw, which requires a considerable time commitment from the family and the physicians. Therefore the goal of project is to design the new automated Rapid Maxillary Expansion (RME) appliances, which encompasses the benefits of current devices and is easily adjustable.

Articular cartilage is the bearing material of diarthrodial joints as hydrated soft material such as knee, hip, shoulder, and etc. Then articular cartilage has exceptional lubricating properties and low coefficient of friction that greatly assist its function in synovial joints. Some studies of cartilage lubrication have hypothesized that pressurization of the interstitial fluid may contribute predominantly to reducing the friction coefficient at the contact interface of articular layers. In this paper, we present the response of interstitial fluid pressurization within hydrated soft material of cartilage, which accounts for the cartilage defects. For the computation model, we have chosen an axisymmetric model with two uniformly thick cartilage layers and solved by using finite element method. This model demonstrates that a simultaneous prediction of compression experiments of articular cartilage were under stress relaxation and dynamic loading. For the experimental results, we found that the increased fluid concentration of the tissue’s solution can be achieved the minimum friction coefficient. Furthermore, it is observed that the friction coefficient does not remain constant under various loads or fluid concentration and correlation analyses that the equilibrium value depends in part on the compressive strain in the cartilage.

Purpose: The aim of this study is to investigate the effects of concrete vs. abstract tasks on reaching and postural performance during standing.—Methods: Twenty subjects with left cerebral vascular accidents (LCVA) and 15 age-matched healthy subjects performed the tasks under the target present vs. the target absent conditions with their less affected arm during standing. The condition of target present required the patients to push the glass forward as far as possible whereas the object absent condition involved reaching forward along the track as far as possible. The reaching performance was measured by forward reaching distance, and the postural control by derivatives of center of pressure (CoP) including forward displacement (FD), medial-lateral (M-L) shift, and average velocity (AV) of CoP.—Results: The LCVA group showed significant effects on reaching distance and AV of CoP. The control group demonstrated significant effects on AV of CoP.—Conclusion: The findings of this study partially support the notion that target present task optimized task performance. Beneficial effects were found on reaching distance and AV of CoP in healthy adults and on AV of CoP in LCVA patients, indicating LCVA patients demonstrated deficits in response to task target. These finding have implications for postural trainings in patients with stroke.

The problem of finding and predicting muscle activations for free goal oriented or measured human motion is one of the basic problems in biomechanics. While currently inverse dynamics approaches are most commonly used for their computational efficiency, they can not handle the problem in its most general form. We here present computational methods that increase the computational efficiency of the forward dynamics approach by two orders of magnitude. Results are presented for a time optimal kicking motion and the analysis of a measured kicking motion. Current work includes investigation of a jumping motion and finding optimal walking motions for a robot that is driven by artificial muscles.

Analysis of foot-floor reactions during one’s locomotion can be helpful for clinical diagnosis of his dynamic stability, walking ability, and balancing performance. The objective of this study is to design a pair of instrumented shoes to measure ground-reaction forces of persons with stroke in their level walking, stair ascending and descending. This study integrates a pair of instrumented shoes and a microprocessor-controlled data logger to build a portable system for measuring vertical foot-floor reaction forces. The instrumented shoes consist of 14 load cells, adjustable shoe modules, and signal conditioning circuits. The system is capable of synchronizing with a video recorder and continuously acquiring data up to 2h under a 100 Hz sampling rate. Plantar forces of 5 healthy adults and 6 persons with stroke were measured in their level walking, stair ascending and descending up to 10min. Their temporal and spatial gait parameters were calculated using analysis software programmed by LabVIEW. The instrumented shoes have 0.08 % and 1.72 % averaged static error and dynamic error, respectively, and were proved to equip with portability, high resolutions, and long operation time. Significant group differences were found in force waveforms, COP loci and bilateral symmetry of temporal and spatial gait parameters. Furthermore, the force waveforms and COP loci seems to accordingly reflect the severity of participants with stroke. Experiment results show the system is capable of acquiring foot-floor reaction forces for both normal and pathological gaits and can derive adequate parameters for clinical diagnosis.

the aim of this study is to use kinematic analysis to investigate the speech motor control in children with CP. We collected 10 children with CP having spastic quadriplegia. Another 10 children with normal development (ND) were selected as control group. A motor analysis system (Vicon 370) and a mobile video were synchronized to collect kinematic data and video images during speaking. Each subject received /pa/, /pi/, /pu/, /po/ mono-syllable tasks. Kinematic parameters included the spatiotemporal indexes (STIs), duration, peak velocity of jaw, and peak displacement of lower lip during speaking. Statistical significance was set as

p

less than.05. The results showed CP with spastic quadriplegia had greater STIs in /pa/, /pi/, /pu/, and /po/ tasks (

p

<0.05), and larger peak velocity of lip in /pi/, /pi/, and /po/ tasks than children with ND (

p<0.05

). Children with CP non-progressive brain damage may cause impairment in cognition, language, and motor speech functions. Therefore, CP children had greater STIs and peak velocity of lip. Kinematic data of motor speech control provided in this study may allow clinicians to understand the motor speech control with children with CP.

Sit-to-stand, (SiSt) exercise is an exercise which is simple and easy to be implemented. A seesaw is an example of basic mechanism which is able to assist a person, especially paraplegic to perform the exercise. Understanding the dynamics of motion would beneficial to rehabilitation engineering field which is a study to improve the quality life of disability people. This study presents a dynamic simulation of humanoid model performing sit-to-stand (SiSt) exercise. The main goals of this project are; the development of humanoid model with seesaw exercise machine, and the development of controller for controlled movement of the system. To achieve this, a humanoid model with seesaw mechanism have been designed in Visual Nastran software, while a closed loop system with PD, (proportional-plus-derivative) controllers that track desired reference input have been implemented by Matlab/Simulink. Here, both software packages (Visual Nastran and Matlab/Simulink) have been integrated in order to produce the simulation of humanoid motion. The simulation result of humanoid model performing SiSt mode with seesaw mechanism proved the developed models and the designed controller are able to perform and function as desired before will be implemented into FES application.

Background: Most factors cause motor and gait impairment in patients with dementias are related to lesion of different areas and lobes. However, patients with different types of dementias may have distinct motor impairment features because of different neuropsychological dysfunction that may resulted in different motor features.

Objective: To compared patients with mild Alzheimer’s disease (AD) and patients with mild vascular dementia (VaD) in motion analysis of gait and hand function.

Participants: The subjects were recruited into three groups: Group I.healthy elderly (HE) ,n=10; Group II. Mild possible Alzheimer’s disease (AD) ,n=10; Group III. Mild possible vascular dementia (VaD) ,n=10. This study was used Clinical Dementia Rating Scale(CDR) to diagnosis the dementia severity. The including criteria for dementia patient was CDR scale below 2 which means mild dementia.

Design: In this study, motion analysis was used to evaluate the kinematic parameters to compare gait performance, hand function was measured by a new designed computer board. In gait aspect, there were three motor tasks: (1) comfortable walking;(2) comfortable walking combined dualtask;( 3) comfortable walking combined dual-task (memory). In hand function evaluation, there were three motor task: (1) sequence task;(2) sequence task combined dual-task;(3) random sequence task. Dual-task in this study was asked subjects performance secondary task at the same time which invert three numbers experimenter recited. The data were been analysis through two-way mixed ANOVA to compare within and between groups.

Result: There was no different motor ability in gait and hand function of AD group compared with VaD group in single- tasks. However, they were significant different represent in dual-task. Besides, AD group had more variation than VaD group in dual-task. Among them, the change of hand function seems more sensitive than gait in biomechanical analysis in dual-task.

Conclusion: Patients with AD present poor motor strategies than VaD in dual-task of gait and hand function. Among them, the change of hand function seems more sensitive than gait in biomechanical analysis in dual-task.

This paper describes the investigation of Surface Electromyography (sEMG) signals of back muscles and hamstring muscles during forward flexion and extension in healthy and low back pain (LBP) women. There were two groups of Malaysian females aged between 20 to 55 years old voluntary participated in this study. Group 1 consisted of 10 healthy females while group 2 consisted of 6 females suffered with low back pain. Every subject was trained to perform two types of forward flexion; maximum forward flexion (bowing as far as they can) and 90° forward flexion with hands on the knees. The electromyogram (EMG) and the motion signals were recorded during forward flexion of the trunk at the back and hamstring muscles. The findings indicated that the flexion relaxation phenomenon (FRP) was found only at the back muscles in healthy subjects during full flexion of the trunk, however it was absent at the hamstring muscles. For low back pain patients, the FRP was absent in both muscles. Mann-Whitney test showed astatistically significant differences in flexion relaxation ratio (FRR) between two groups during maximum forward flexion (p<0.05) and 90° forward flexion (p<0.001).

Background and Purpose: Sleep, a vital ingredient in life, is an active and complex rhythmic state that may affected the health of people. Based on theory, sedative music may induce relaxation and distraction responses. Music also has the effect on the change of muscular energy, heart rate and respiratory rates, blood pressure, and psychological distress. Choice the good pillow and environment could enhance good sleep in quality. The purpose of this study was use music pillow for good sleep.

Methods: The test on effect of music pillow for sleep promotion includes two conditions, music pillow or non-music pillow. Six people aged 20–30 years in normal state of sleep will be included into this study. Participants listen to sedative piano music with or without block sound one hours in the naptime for four days. Polysomnography was used for recording of sleep and physiology variation.

Preliminary results: From the result of sleep promotion, people sleep with music pillow had shorter period of latency to fall asleep than without music. Slow down of heart rate was also found. Music can promote the rapid onset of sleep in young people , block sound might enhance the effect of music for the onset of sleep in young people.

Conclusion: People sleep on pillow with music could promote sleep. Block sound might enhance the effect of music for the onset of sleep in young people.

The intention of this article is to introduce and overview Pneumatic Artificial Muscles (PAMs). The construction of PAMS mainly consist of flexible, inflatable membranes, having orthotropic material behaviour. The main properties shaping the PAMs will be explained in terms of their loadcarrying capacity and low weight in assembly. Discussion on their designs and capacity to function as locomotion device in robotics applications will be laid out, followed by viewpoint on the materials and strength models, concluded by some future directions in this research work.

To find out the optimal height of pillow fit for comfortable sleep, we used manual measure, 3D body scanning system, and FSA Pressure Mapping (pressure imaging) System to establish an anthropometric database for the adult populations.

The replacement of an injured anterior cruciate ligament (ACL) using minimum invasive techniques is called an arthroscopy knee reconstruction (AKR). A strong biologic substitute is necessary to restore this primary stabilizing structure of the knee. To perform this, a natural graft is first harvested, then two bone tunnels are drilled in the tibia and the femur. Finally, the graft is inserted inside these tunnels and fixed using screws. A wrong positioning of one or both tunnels can easily lead to a failure of the graft. As the ACL graft geometry does not fit the original ACL shape, the goal, when placing the graft, is to obtain an isometric behavior for it during knee flexion. However, because only a small area of the graft section is isometric, even in the best case, the graft is subjected to stress during flexion, and may fail if this stress is above its failure threshold. Within this context, we investigate the use of an online physical model to virtually simulate the stress and strain conditions of the ACL graft

before

the tunnels are drilled. This information can help surgeons make a better decision when positioning the graft.

Since our last report on biomedical engineering (BME) education and training in Hong Kong which was presented at the 6

th

Asian-Pacific Conference on Medical and Biological Engineering (APCMBE 2005) more than one and half years ago, there have been significant developments in this field in Hong Kong. This paper gives an update of the status of BME education and training in Hong Kong. It also looks into some critical issues in a wider context. The experience gained and lessons learnt with regard to BME education and training in Hong Kong may prove to be useful for BME developments in other parts of the world.

Percutaneous image-guided needle biopsy is typically performed in highly vascular organs or in tumors with rich macroscopic and microscopic blood supply. The main risks related to this procedure are bleeding and implantation of tumor cells in the needle tract. From numerous conducted studies, it was found that heating the needle tract using a radiofrequency (RF) ablation system has a potential to minimize these effects. However, this solution requires the use of specially designed RF needles which would make the procedure relatively expensive and complicated. Thus, in order to solve this problem, we propose a simple solution by using readily available biopsy needles connected to an RF generator. In order to do so, we have designed and developed an adapter to interface between these two devices. A bovine liver has been used as a sample tissue for the experimental procedure. The delivery of the RF was varied by varying the values for delivered power, power delivery duration, and insertion depth. The results showed that the size of the coagulation necrosis region is affected by all of the parameters tested. In general, the size of the region is enlarged with higher delivery of RF power, longer duration of power delivery, and shallower needle insertion.

This paper describes a study of Opaque Object Filter to extract region with nodule from chest x-ray image. A gray level chest x-ray image is preprocessed using Euler number algorithm to extract lung region. Defined Euler number algorithm is a statistical extraction of data obtained from Euler numbers for binary image. Suitable threshold value is computed based on minimum and maximum of the correlated gray scale value. After lung region was extracted, we applied our defined Opaque Object Filter to extract nodules image window. We use defined filter to perform heuristic search through the chest x-ray image. Defined Opaque Object Filter utilized radius and spatial axis vector analysis to extract nodules image window. Noise filter is defined to eliminate the border of lung area effects. A flow chart for the search is introduced. Initial result shows the filter is able to extract nodules image window within chest x-ray image

This paper presents an automatic cell counting method for a microscopic tissue image from breast cancer. We perform color space changing from RGB to CIELab and anisotropic diffusion filtering for noise removal in the preprocessing stage. Subsequently, the segmentation algorithm based on local adaptive thresholding, morphological operations, and cell size considerations is performed. In order to obtain the more correct counting number of cancer cells, we further process the image containing attached cancer cells with marker-controlled watershed segmentation. Results from our automatic counting approach show a promising solution to the traditional manual analysis. That is, the counting number of cancer cells from the automatic approach is comparable to that from a specialist.

The research explores various methods to retrieve microscopic blood cell image on the basis of features automatically extracted from the image. The query image is selected from a large collection of blood cell image. After the region of interest is selected from the image, Query by Image Content (QBIC) catalog is used to measure the low level attributed of the query image such as average color, histogram color, positional color and texture. The low level attributes are used to find matching image in the DB2 (DataBase 2 by IBM) database. The most accurate and relevant blood cell images are retrieved along with the description of the blood disorder.

A method for echocardiogram boundary enhancement using local image characteristics and Ratio-of-Averages (RoA) is proposed in this paper. Local image characteristics, namely “steepness” and “symmetry”, are used along side with RoA to determine “edgeness” of the image. The task is achieved by employing a fuzzy inference system where fuzzy sets and rules are derived heuristically to define “edgeness”. All results obtained are compared to a standard edge detector and a similar method without RoA for quantitative and qualitative performance evaluation.

The technique of modification of the histogram of an image can be applied to the problem of image enhancement. Global histogram equalization and local area histogram equalization are two well-known techniques for the same purpose. In this paper new method is proposed to enhance the contrast of bimodal MRI images using histogram specification with Gamma distribution. The method is aimed to read the original image and calculate its histogram original histogram then apply the Maximum Likelihood Gamma Distribution (MLGD) method to get an accurate statistical information of the original histogram as the means and

prior

probabilities of the two modes, then we separate the two modes by shift the first mode left or shift the second mode right or perform both shifts. After that we will generate a new histogram called “Desired Histogram” using the new data. By applying a histogram specification method, a high contrast image will be produced. The new method of contrast enhancement of MRI image using histogram specification with Gamma distribution has been tested and showed good results.

The Lunar DPX-IQ is a bone densitometer from the Lunar Corporation (now part of GE Healthcare), and was released around the year 1997. The main control system is built upon the MS-DOS operating system, and stores its data in a proprietary database and format. The system is not DICOM compatible, has no built-in computer networking functionality, and does not have any functionality to export its images or data to any standard format. With the ongoing consolidation and centralization of modality data, the Lunar DPX-IQ risks being prematurely retired from service due to its inoperability with other systems.

This paper describes an early effort to extract a digital copy of the scan data in a standard format from the DPX-IQ. We have made no attempt to implement DICOM compatibility or other advanced functionality, though our effort may be seen as a first step towards a more comprehensive solution. Our method revolves around redirecting and capturing the printer data stream via port redirection, followed by a PCL to PDF conversion resulting in a digital copy of the scan report ready for archiving. Future improvements to the project will focus on a parser to extract patient and study metadata from the captured PCL file. Complete DICOM-ization of the data may continue from there.

This paper is a study of using Spatial Grey-Level Co-occurrence Matrix (SGLCM) and First-Order Statistics (FOS), for characterization of liver tissue. SGLCM and FOS are applied on three modalities of liver images, consisting of Magnetic Resonance Imaging (MRI), Ultrasound and Computed Tomography (CT), for the diagnosis of liver diseases. The results indicate that the proposed texture analysis methodology is able to characterize cyst, fatty liver and healthy liver in clinical test images with high success rates. The study indicates viable use of SGLCM and FOS in multimode image analysis and development of a texture-based multimode computer- aided diagnostic (CAD) system for liver diseases.

This paper presents a method for speckle noise reduction as well as feature extraction in medical ultrasonic images to effectively reduce the speckle noise and extract the object in ultrasonic images. In noise reduction process, the logarithm transform of the ultrasonic image is analyzed into wavelet domain by using 2D stationary wavelet transform (SWT). Next, the Weiner filter is used to apply over areas in each subband (HH, HL, LH and LL). Finally, the inverse wavelet transform is computed and applying the exponential. In feature extraction process, first the denoised image is enhanced by histogram equalization technique. Haar filter is used to extract the object. Moreover, nonmaxima suppression technique is adopted to get the edge localization. Finally, the adaptive hysteresis thresholding is applied to get the final result. The experiments show that the proposed algorithm can be detected well-localized and thin edges.

In this study high resolution imaging of human adult (HaCaTs) Keratinocytes cells using the newly developed Widefield Surface Plasmon Resonance (WSPR) system will be discussed. Surface Plasmon Resonance (SPR) occurs at the interface between a dielectric and a thin conducting layer when p-polarized light strikes at a specific angle thus excites free electrons and generates surface plasmon electromagnetic wave. The SPR excitation angle can be changed by the binding of bio-molecular species to the metallised layer, and is directly proportional to the refractive index and thickness of that molecular species. Our WSPR system provide high lateral resolution imaging close to 500 nanometers [1] and was used to investigate cell surface interactions under two different culture conditions: HaCaTs cultured on SPR substrate with Transforming Growth Factor β3 (TGFβ3)

(50ng/ml)

[2] and without TGFβ3. In less than 24 hours, HaCaTs cultured in the presence of TGFβ3 showed enhanced division and motility along with decreased cell attachment as compared with cells maintained in TGFβ3 free media. It is to be noted that cellular signaling by TGFβ3 is very important for enhancing tissue development in wound repair and that this study for the first time enabled optical interrogation of cell surface interface without the need for Immunostaining.

Early, accurate and efficient screening of tumour will go a long way to improve the life expectancy and quality of life. Microwave holographic technique uses nonionising radiation which has the potential to screen patients for tumour at low cost. It offers high contrast between healthy and malignant tissues and assists in forming image of the location and the extent of the malignant tissue. This technique exploits the advantages of holography without requiring the direct measurement which uses an expensive network analyser.

This paper will investigate the use of an alternative microwave imaging technique using indirect holographic method. The use of continuous wave signal for imaging avoids the problems associated with pulsed systems. The use of two stage holographic technique requires recording of a holographic interference pattern as stage one and reconstruction of original image of the object as stage two. As a preliminary study, the transmitted microwave signal is bombarded on a suitable phantom and the scattered signals are measured. The significance of this technique is that it offers real time imaging possibility which can be used as intra operative imaging tool during the surgery to remove tumour.

Common methods for deriving pressure value from velocity images, use Computational Fluid Dynamics (CFD) techniques. One of the major restrictions is that these images are prone to noise and they have low resolution. In this study we developed a domain approximation approach using least-square fitting methods to overcome these problems. In this regard in this first challenge a one-dimensional mathematical flow phantom is approximated by a polynomial function. The results obtained from the proposed technique are compared by the CFD approach. The effect of accumulation of noise and the effectiveness of this technique in estimation of pressure domain is also evaluated.

Tissue engineered heart valves are a promising alternative for current heart valve replacements. However, the mechanical properties of these valves are insufficient for implantation at the aortic position [1]. Collagen orientation is important to improve the mechanical properties of tissue engineered valves. Two-photon laser-scanning microscopy allows us to study the influence of strain on collagen orientation in 3D. A method based on the 2

nd

order derivative of the 3D image structure was used to determine the general orientation of the collagen fibers with automatic scale selection of the operator. We studied the effect of strain on collagen orientation. Alignment in the direction of the applied strain is seen. Histograms show that the distribution of orientations becomes smaller for increased strain. This indicates that the collagen fibers align more.

Texture is often considered as a repetitive pattern and the constructing structure is known as texel. The granularity of a texture, i.e. the size of a texel, is different from one texture to another and hence inspiring us applying scale space techniques to texture classification. In this paper Gaussian kernels with different variances (σ

2

) are convolved with the textures from Brodatz album to generate the textures in different scales. After some preprocessing and feature extraction using principal component analysis (PCA), the features are fed to a combined classifier for classification. The learning curves are used to evaluate the performance of the texture classifier system designed. The results of classification show that the scale space texture classification approach used can significantly improve the performance of the classification especially for small training set size. This is very important in applications where the training set data is limited. The application of this method to ultrasound liver tissue characterization for discrimination of normal liver from cirrhosis yields promising results.

This paper presents a spinal curvature determination from frontal X-ray images of scoliotic patients. A new deformable model, Modified CPM (Charged Particles Model), has been developed and used to determine the spinal curvature. The Modified CPM is a new approach of a deformable model based on CPM, which was introduced in 2004. The X-ray image is charged negatively according to the edge-map or gradient-magnitude image. The particles are attracted towards the contour of the object of interest, because this contour is very dark, thus charged very negatively. We modified the CPM by putting springs between the particles to prevent the particles from moving away and keep the movement of the particles in the appropriate distance without reducing the flexibility to follow the curvature. The results of the implementation show the effectiveness of the modified charged-particle model for spinal curvature determination on X-ray images.

In industrial application, image thresholding has been widely used due to the simplicity of implementation and time execution. Many entropy algorithms have been developed for image thresholding. Gamma distribution showed good result in the modeling of data in images. Gamma distribution has a general shape than the Gaussian distribution. In this paper, we developed a fast iterative method from minimum cross entropy thresholding using Gamma distribution. Experimental results showed that the use of Gamma distribution produced good results.

Laser interstitial thermotherapy (LITT) is an internal ablation therapy consists of the percutaneous or intraoperative insertion of laser fibers directly into the liver tumor with maximum diameter of 5 cm. It is very important to control temperature increasing non invasively, because on high temperatures, tissue carbonization occurs and it can damage normal tissues. In this research, pixel shift changes on ultrasound B-mode images with temperature were measured. LITT in vitro was performed on 11 freshly sheep liver tissues using a Nd:YAG laser with a bare-tip optical fiber. Invasive temperature monitoring was performed during heating and cooling down by fixing micro thermocouples on tissue. At the same time, noninvasive temperature monitoring was performed with ultrasound B-mode images. The speed of sound variations with the temperature changes are create virtual shifts in scattering positions and time shifts into the received echo signals. It can locally cause pixel shifts on B-mode images. These pixel shifts were measured by echo tracking algorithm. Linear and nonlinear regression analysis between independent variable (temperature changes) and dependent variable (pixel shift on images) were performed. It was shown that with correlation coefficient of 0.892, cubic function was suitable. In this method, because of bubbles formation and tissue carbonization, monitoring of more than 100°C, was difficult. This method could be used for noninvasive temperature monitoring for a large number of patient, during LITT.

Image segmentation, i.e., identification of homogeneous regions in the image, has been the subject of considerable research activity over the last three decades. Segmentation of images is a major task of image processing. There is no general segmentation procedure that can deal with all sorts of images, and the correct solution will always depend to a certain degree on subjectivity. Many algorithms have been elaborated for gray scale images. Those algorithms are based on different methods including: classification-based methods, edge-based methods, region-based methods, and hybrid methods. Iterative Self-Organizing Data Analysis Technique (ISODATA) is one of the classification-based methods in image segmentation. It is an unsupervised learning Technique. Statistical approach is wieldy used in image processing in order to model the data of image. Gaussian and Gamma distributions have been used in this technique. Gaussian can only approximate a symmetric shape of histogram. Gamma distribution can only approximate a symmetric and a skewed to right shapes of the histogram. However, Beta distribution is more general than Gaussian and Gamma, and it can approximate any shape of histogram as skewed to left, skewed to right, and symmetric. The algorithm developed here is based on the technique of unsupervised learning using a mixture of Beta distributions. Experimental results are presented to show good performance on segmentation of skin images.

Attention is currently focused on fiber optic immunosensor as sensitive and nearly real time protein detector. This kind of sensor is expected to detect bacteria in foods directly by dipping the thin optical fiber dominant area into foods. In the study, an antibody based fiber optic immunosensor to detect

Escherichia coli

O157:H7 (

E.coli

O157:H7) was constructed. The principle of the sensor was a sandwich immunoassay on the optical fiber surface. A goat polyclonal antibody was first immobilized on polystyrene optical fiber.

E.coli

O157:H7 and a cyanine 5 (Cy5) -labeled goat polyclonal antibody were used to generate a specific fluorescent signal. An excitation light (λ = 635 nm) was illuminated into the optical fiber, and the Cy5 florescent molecules near the optical fiber (approximately 100 nm) were excited by evanescent wave emitted from the optical fiber. The fluorescent light (λ = 670 nm) collected by the optical fiber was measured using a photodiode. The measurement range for

E.coli

O157:H7 diluted with phosphate buffer (PB) was from 1×10

2

to 1×10

7

cells/ml. This method could also detect

E.coli

O157:H7 in milk artificially inoculated with 1×10

2

to 1×10

7

cells/ml. This immunosensor was specific for

E.coli

O157:H7 and showed significantly higher signal strength than for nonpathogenic

E.coli

or other bacteria, including

Listeria monocytogenes

and

Vibrio s.p.

, in pure or in mixed-culture setup. The results could be obtained within about 15 min of sampling.

This paper overviews various components of MEMS drug delivery devices in medical application such as micropumps, microvalves, microactuator and microneedles, using biocompatible material such as silicon. The review will focus on micropumps structures in different actuators. The electrostatic actuated micropumps and circular bossed membrane were found out to be the most suitable device for medical application and offer better linearity pumping rate respectively.

The area of micro fluidic system is a significant sub-component of micro-electro-mechanical systems (MEMS). Many of these MEMS applications will require components of dynamic fluids, either of Newtonian or non-Newtonian characteristics to be pumped into micro-ducts. At such small scales this is a rather gigantic challenge. Some of the early reviews on micro-channel analysis, at the very basics liken micro-channel design (device design) to a macro channel design e.g. piping design. Reasonably, conventional fluid mechanic laws govern these design analysis; laws which are often violated in the micro-environment. This paper appraises the approximation of micro-fluid engineering to macro-fluid engineering and key parameters which contradict to conventional fluid laws. Subsequently this paper also discusses the role of micro-fluid analysis in design; specifically in bio-MEMS applications.

This article provides an overview of Bioelectrical Impedance Analysis (BIA) and its merits over other body composition methods. BIA phase angle technique is fast emerging as an independent clinical tool besides being a good and practical in-vivo method for estimation of human body composition. Body composition analysis is used in preventative, therapeutic, and research applications such as nutritional assessment, anti-aging therapy, physical performance assessment, weight management, obesity, fluid and nutritional assessment etc. Based on these developments, current and future clinical applications and directions of BIA research are discussed.

Heart rate variability (HRV) analysis is gaining acceptance as a potential non-invasive means of cardiac assessment in clinical as well as research domains. Although it is a standard practice to derive HRV from the R-R peaks of electrocardiogram (ECG), there have been attempts to deduce it from peripheral pulse wave signal. HRV is measured using photoplethysmographic (PPG) pulse wave signal in this work. A versatile algorithm governed by the physiology of the cardiovascular system developed by the authors is used to derive peak intervals from the PPG signal. In addition to normal time and frequency domain techniques, sequential trend analysis (STA) is applied to analyse HRV. Out of 20 subjects monitored, the results of three, one healthy and two with known cardiac problems, are presented and discussed. In all cases monitored, the results of HRV deduced from PPG are in tune with clinical picture of the subjects. The usefulness of STA in the analysis of HRV is also discussed.

Porous polysilicon is a biocompatible, non-toxic and biodegradable material, thus making it a suitable material to be implanted into human body as a drug delivery device. In this study, the method of stain etching in solution consists of HF, HNO

3

and H

2

O in a ratio of 1:3:5 by volume has been used to create the nano-porous structures. The etching time was less than 30 seconds on a LPCVD polysilicon with sheet resistance of ∼28 Ω/sq. The topography of the surface was then investigated by Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM). The resulting porous structure also exhibits a photoluminescence (PL) peak at around 700nm. The fabricated porous polysilicon is suitable as the material for an implantable drug delivery device, which offers significant advantages such as the ability to avoid dose dumping and providing patients with the required drug dosage over an extended period of time.

In this study, Human adult, low Ca2+, high Temperature (HaCaTs) Keratinocytes were cultured on microcontact printed fibronectin repeat gratings of 1.8, 3.8, 5, 12.5 and 25µm for 24 hours. The cells were then fixed with 0.1% Glutaraldehyde and dehydrated in serial alcohol [1]. The alignment of the cells were then measured, where 0° represents 100% alignment to the pattern, in order to identify those features that promoted the highest degree of cell alignment. From the quantitative analysis it became clear that HaCaTs cells align most readily to the 12.5µm pattern. A 12.5µm stamp was therefore used to stamp pattern fibronectin on to prefabricated Au/Cr/glass surface plasmon substrates. HaCaTs cells were cultured on the substrates for 24 hours and imaged with the “Widefield Surface Plasmon Resonance” (WSPR) microscope

Generic aspect in the automated detection of obstructive sleep apnea hypopnea (OSAH) events based on only oxygen saturation (Sp02) is investigated. The objective is to develop and verify an algorithm (GTA) capable of generalizing three auto detection algorithms (ADA, DDA, MNA) which represent the classical threshold algorithms based on clinical definitions for desaturation. This is the first attempt a generic algorithm is developed for the classical threshold algorithms for automated detection of desaturation. This makes efficient the benchmarking of new automated algorithms for the detection of OSAH events based on the analysis of Sp02 alone, in terms of time, cost and resources. GTA is the consequence of recognizing a common pattern in the response characteristics of ADA, DDA, MNA and generalizing them. The most significant contribution is the reduction from three different auto detection procedures to two rules for event extraction and another two for event authentication. This has been verified against detection outcomes and operating characteristics. Full agreement is found between GTA and ADA, DDA, MNA with minimal rounding error. The credibility of assessment is founded on a standard comparison basis for all algorithms, which includes database, optimal performance criteria and evaluation method.

Pulse wave velocity (PWV) is a basic parameter in the dynamics of pressure and flow wave traveling in arteries. But it is difficult to measure the pulse wave transmission time between coronary arterial proximal and distal point by manual method using the graph on which pulse wave and ECG are recoded. The system that can measure PWV was developed and the experiment was carried out for one patient to validate the accuracy of the measured coronary arterial PWV. The average value of the measured coronary arterial PWV was 936.571±105.161 cm/sec.

An efficient, very simple and new approach for detection of both base line and QRS complexes from the horizontal and vertical histogram of ECG data is described in this paper. The vertical and horizontal histograms are generated from the number of ordinates for a particular abscissa at the vertical and horizontal direction respectively. The base line is determined at the maxima of the horizontal histogram whereas QRS or R peaks are determined from the local maximas of the maximum area zone of vertical histograms. A very high accuracy level is achieved for both the cases (99.5% for QRS and 92% for base line). The method is advantageous because both QRS and base lines can be determined directly from ECG data without computation of complex mathematical models even when ECGs are tilted due to respiration and in the presence of power line oscillation.

A software based approach for determination of the frontal plane QRS vector is described in this paper. For this purpose, a module is developed for determination of R-R interval of each ECG wave of six limb leads (Leads I, II, III, AVR, AVL and AVF) by using square derivative curve technique. Baseline or isoelectric level of every ECG signal is also determined for accurate computation of net QRS deflection (NQD) at all the six above-mentioned leads. Depending on the rules of cardiac axis determination by searching the minimum NQD, an algorithm is developed for computation of the angle, amplitude and direction of the frontal plane QRS vector for both normal and diseased subjects to find out the clinical significance of this vector in disease identification. In the present work, the PTB diagnostic ECG database is used for computation of the QRS vector and interesting result is achieved.

This paper describes the investigation of the steady-state visual evoked potential (SSVEP) response elicited by a flickering visual stimulus. Preliminary results from five subjects have shown that SSVEP have certain characteristics including good signal to noise ratio (SNR), minimal user training and number of electrodes, despite constraints such as the need for a visual stimulating apparatus and possible induced of visual fatigue. Based on these promising results, SSVEP can be used as a tool for controlling signal for future brain computer interface (BCI) application.

E

lectrooculogram (EOG) signal is the physiological signal that represents the eye ball movements. In this paper, the behavior of EOG signal is studied from the nonlinear and chaotic viewpoint using Hurst exponent, Iterated Function System (IFS) plot, average mutual information and Lyapunov exponent. Our findings indicate that the EOG signal has deterministic chaotic characteristics and therefore can be used in prediction and/or detection purposes.

This paper discusses on the classification of electrocardiogram (ECG) signal using multiresolution wavelet transform and neural network. Multiresolution wavelet transform is used as a method of feature extraction of ECG signal since it has the ability to analyze the signal both in time and frequency domain. Neural network is used because of its ability to learn and perform classification on ECG signal. In this paper, four type of ECG signal has been chosen for classification. Based on the data obtained from MIT-BIH Arrhythmia Database the classification rate is found to be 95.08%.

This study is to investigate the effects of different montaging methods on the classification rate. The EEG signal is recorded from the motor cortex region when the subjects tap the keyboard using the left or right index finger. In this experiment, One subject’s data is downloaded from the BCI 2003 competition and two other right handed subjects participated in a similar experiment. In this preliminary experimental study, we found that the surface laplacian method outperforms other types of montaging.

Complex variations have been observed in heart rate. Analysis of these variations, i.e., heart rate variability (HRV) analysis has become an important non-invasive technique to study the sympathovagal interactions in physiological and pathological conditions. Increasing efforts were made in the development of HRV measures for quantifying heart rate variations in order to make clinically useful assessments of patient welfare. Heart is not a periodic oscillator under normal physiologic conditions and standard linear HRV measures may not be able to detect subtle, but important changes in heart rate time series, whereas, most of nonlinear measures suffer from the curse of dimensionality. To overcome these difficulties, several complexity measures, especially from symbolic dynamics have been proposed. Recently, we have used threshold dependent symbolic entropy to study the dynamics of stride interval time series of control (healthy) and neurodegenerative diseased subjects. Normalized corrected Shannon entropy (NCSE) was used to quantify these dynamics. In this paper, using this technique, we have compared the complexity of normal sinus rhythm (NSR), congestive heart failure (CHF) and atrial fibrillation (AF) subjects. We investigated that the dynamics of healthy (NSR) subjects are more complex than diseased (AF and CHF) subjects within the short range of thresholds.

This paper presents a computer-based system tool used to assess efficacy of stuttering therapy techniques. The software assists Speech-Language Pathologist (SLP) in determining suitable techniques for each client. The project implements Digital Signal Processing (DSP) techniques to analyze speech signals and incorporates standard speech fluency shaping techniques that can be used as part of fluency rehabilitation regimen. The software provides real-time visual and audio feedbacks for clients to be aware of their speech patterns. It provides self training aid for clients that motivates them to practice at home. The software runs under Windows XP on a computer equipped with multimedia capabilities. Real-time visual and audio displays enable the clients to compare their average magnitude profiles (AMPs) with clinician’s and alter their speech to match clinician’s AMP. The start and end alignment, maximum magnitude and duration of two AMPs are compared. A score is assigned to each category. The software is developed using Microsoft Visual C++ 6.0. Software is designed as graphic user interface (GUI), which makes therapy user friendly. Three techniques that are implemented in the project have been decided through the discussion with SLP in Hospital Sultanah Aminah (HSA). The techniques are Shadowing, using a Metronome (Taping) and Delayed Auditory Feedback (DAF). This project is done in collaboration with HSA where the hospital assists in the clinical trial.

This paper describes the development of a bipolar EEG amplifier designed specifically for use in a braincomputer- interface (BCI). AC coupling is performed in the input stage to prevent electrode offset voltages from saturating the amplifier when high gain is used. The amplifier is easily modified to amplify other biopotential signals. The circuit described is suitable for low power consumption, battery power application. The low power requirement of the amplifier allows it to be powered through the USB connection and thus suitable for portable applications.

Preprocessing and signal enhancement methods can be applied to improve quality of signal detection in the presence of background noise. This article concerns the novel preprocessing techniques for enhancement of EEG signals and background noise suppression during epileptic seizure by using Independent Component Analysis (ICA) and Novelty Filtering which employs an artificial neural network performing autoassociative task. ICA is used for removing biological artifacts and noise from EEG signals and stabilizing its probabilistic behavior. At the next stage Novelty Filtering technique has been used to suppress background EEG activities and improvement of signal-to-noise ratio for the detection and identification of epileptic seizure. A novelty filter consist of neural networks of retinotopic topology having a one-to-one correspondence between input and output units to perform autoassociative mappings. Filtering effect is obtained by subtracting the network output from the input vectors. The results show that novelty filtering combined with ICA is a powerful preprocessing tool for the detection and enhancement of epileptic seizure activity in the nonstationary EEG signals.

In this paper, an approach based on adaptive noise cancellation (ANC) is evaluated to extract the fetal heartrate using photoplethysmographic (PPG) signals from the maternal abdomen. Results of simulations using semisynthetic PPG signals are presented which show the feasibility of the proposed technique. Then a mixture of PPG signal is produced by recording the PPG from overlapping fingers from two different subjects in-lieu of the mother and fetus. Results show that a recursive least-squares algorithm is capable to extract the peaks of the desired PPG signal, hence the heartrate, even at a SNR of -34 dB.

Heart rate variability (HRV) represents one of the most promising quantitative markers of autonomic nervous system activity. It is commonly derived from RR interval of electrocardiographic (ECG) signal to evaluate the balance of sympathetic and parasympathetic responses due to the change in heart rhythm. However, in this present study, peak-to-peak interval variability of photoplethysmographic (PPG) signal has been used for the estimation of HRV. Further, to demonstrate the accuracy and feasibility of HRV extraction from PPG signal, finger-tip PPG and standard lead II ECG signals were simultaneously acquired under normal and deep breathing conditions. A comparative analysis of time- and frequency-domain measures of HRV was carried out. The correlation analysis of tachograms of ECG and PPG (Pearson linear correlation coefficient 0.9698 and 0.7389 under normal and deep respiration respectively) and error analysis of HRV parameters suggest that PPG can be considered as a simpler and reliable alternative for the HRV analysis and estimation of autonomic regulation.

This Project describes the benefits of using an FPGA as a Co-processor for Digital Signal Processor, for increasing speed and reducing the power consumption. This approach uses the advantage of fine grain parallel operation of FPGA. An ASIC implementation of a filter algorithm might have numerous MACs so that, all the taps can be processed in parallel. Likewise, FPGA has a flexible architecture that can be used for all MAC operations in parallel. Programmable logic combines the flexibility of a general-purpose DSP and ASIC. In this project the Spartan 2E FPGA has been interfaced with TMS320C6711 DS Processor. The speed is improved 453.52 times than the conventional DSP processor implementation.

In this paper we first explain how EEG signals can be described using Lommel functions. When the Lommel functions are allowed to time-evolve and analysed using the method of instantaneous frequency, we obtain a frequency modulated harmonic spectrum. This perspective allows new insights in interpreting the nonlinear behavior of EEG signals such as chaos.

This paper presents heart sound analysis method based on Time-Frequency Distribution (TFD) analysis and Mel Frequency Cepstrum Coefficient (MFCC). TFD represents the heart sound in term of time and frequency simultaneously which while the MFCC defines a signal in term of frequency coefficient corresponding to the Mel filter scale. There are 100 normal data and 100 data with disease obtained from the hospital which consists of various kinds of problems including mitral regurgitation and stenosis, tricuspid regurgitation and stenosis, ventricular septal defect and other structural related disease. B-Distribution is chosen from a number of time-frequency analysis methods due its capability to represent the signal in the most efficient way in term of noise and cross term reduction. The advantage of MFCC is that it is good in error reduction and able to produce a robust feature when the signal is affected by noise. SVD/PCA technique is used to extract the important features out of the B-Distribution representation. The coefficient obtained from SVD-PCA and MFCC is later used for classification Artificial Neural Network. The results show that the system is able to produce the accuracy up to 90.0% using the TFD and 80.0% using the MFCC.

An approach is proposed to determine the transfer function of the human heart-to-finger upper-limb vascular segment. The instant of occurrence of the left ventricular blood pressure was estimated using simultaneous electrocardiography and photoplethysmography (PPG). A well-established, generic shape is assumed for the left-ventricular pressure. The weights of an adaptive finite impulse response filter were tuned using a least mean-square algorithm so that the output of the model fitted measured peripheral volume change pulses. Results show that the above iterative system identification scheme eventually converges to a set of filter coefficients representing the subject’s vascular segment. A potential application of this technique is to gain more insight into the mechanical properties of the arterial wall, namely compliance.

EEG-based brain computer interface (BCI) provides a new communication channel between human brain and computer. The classification of EEG data is an important task in EEG-based BCI. In this paper we present a new modification on classic “Template Matching” to make a better detection for a specific pattern in EEG. The new method shows a significant improvement in P300 detection which is a common approach in BCI systems. The proposed model uses more than one scalp electrodes and combines the outputs with a fuzzy technique, to detect P300 cognitive component.

Discrete wavelet transform is performed on near infrared spectroscopic data as a preprocessing step in calibration and prediction of active substance concentrations in phosphate buffer solutions. Wavelet coefficients from different scales are used as predictor variables to build regression model via partial least squares. The prediction results are compared with calibration model developed from raw spectroscopic data (without wavelet transform). The wavelet scale, which gives the best-improved prediction accuracy, is selected to form prediction model.

The performance evaluation of Coifman wavelet for ECG signal denoising is presented in this paper. The Coifman wavelet family was use to evaluation its performance on the denoising of ECG signal. The denoising technique was performed by forward discrete wavelet transform up to decomposition of 5 levels, soft thresholding on the wavelet coefficients and inverse discrete wavelet transform. The Signal to Noise Ratio (SNR) in dB is used as a numerical measurement of denoised signal quality. The ECG Signal was obtained from MIT-BIH Arrhythmia reference database. White gaussian noise was added to the clean reference ECG signal to produce the noisy ECG signal with 3 noise levels of initial SNR of 6.5dB, 16.1dB and 20.5dB for denoise evaluation. The evaluation results shows that Coifman

N

= 5 wavelet achieves the best overall denoise performance at all 3 noise levels for ECG signal with the SNR improvement of up to 6.3dB. The evaluation results presented in this paper provide a basic reference for Coifman wavelet family selection for ECG signal denoising applications.

In this paper, the photoplethysmographic (PPG) pulse amplitude response to flow-mediated dilation (FMD) is investigated. Vessel dilation is induced in the right-arm brachial artery (BA) in response to a shear force due to the sudden opening of the BA following supra-systolic blockage of blood supply for 4 minutes. The diameter of the BA is recorded through ultrasound imaging measurement before and after blockage. Concurrently, PPG of the left and right index fingers are recorded before blood occlusion (baseline) and after release. Results on ten human subjects (age 49.7 ± 10.4 years, range 34–64 years) show that the PPG pulse amplitude measured at the finger of the stimulated arm shows a very distinctive pattern associated to the FMD in the conducting artery. A potential application for the proposed technique is the evaluation of the vascular endothelial function, using a significantly lower-cost and less operator-dependent alternative to conventional ultrasound-FMD.

Wearable computer is new trend and it will make healthcare service/system changed in the future. Photoplethysmograph (PPG) is very useful to measure indirectly heart rate, blood oxygen saturation (SpO

2

) with a little constraint. Therefore, many researchers in the field of ubiquitous healthcare and pervasive computer are using the PPG, one of vital signals related to human physiological information, to monitor human health condition. However, the signal is weak and sensitive to motion artifacts. In this study, we applied the scaled Fourier linear combiner (SFLC) to remove effectively the motion artifacts as well as background noise. The proposed method would be useful to reduce the movements and background noise which are non-periodic signal as well as asynchronous signal with heart rate.

A new method for visualization of EEG-process is developed, using factorial analysis. This method permits data compression and visualization in form adequate for human to trace continuous change patterns, compare data from brain hemispheres and delete appearing artifacts using combined man-computer mode for achieving additional reliability. Accordingly, this method is realized in software which allows an operator to select various modes of representation of results and speed of visualization.

One of the most important aspects of new researches in both engineering and medical sciences is to extract useful information from biomedical signals and find a reliable method for machine to learn it which makes the BCI a common field of interest for researches from both groups. Developing a reliable machine learning method plays a very crucial role in this issue. For a typical problem in BCI, ERP detection task, the major method is to classify the input EEG time series into two classes; with a desired ERP/Cognitive Component and without that desired ERP/Cognitive Component. Any powerful feature extraction or classifier block that can do this task accurately, can be of a great help. In this study, a new classifier based on modular learning strategy and a new wavelet for feature extraction, will be introduced and compared with some other classifiers in two states; with GA and without GA, which shows a an improvement in classification accuracy.

In this paper, we present a compression technique for the acquired Electro-oculogram (EOG) signals. Researchers in the past have mainly focused on the EOG signals while dealing with Electroencephalogram signals for the removal of Ocular Artifacts. From a new perspective, a scheme pivoted on multi-resolution analysis and the Wavelet Transform theory was used essentially to process and enhance nonstationary and time-varying EOG Signals. Coiflet wavelets were used for the compression of EOG signals by thresholding of wavelet coefficients.

As we know different brain regions have specific functions. And also before performing any surgery on the brain, including surgery for the treatment of epilepsy, the surgeon seeks to understand the functions of the areas affected by the seizures or of the lesion. The attempt to specify in as much detail as possible the location of function in the human brain is called Brain mapping. In this paper we produced Brain mapping from digitized EEG data recordings. And we developed our software to obtain continuous movie map and spect slide. And also we made it possible to be real-time and wireless for getting the best results.

The effect of aromatherapy on the brain signal is investigated to find the correlation with the heart rate, blood pressure and mathematical computation. First the experiment is conducted to find the effect of aromatherapy on heart rate, blood pressure and mathematical computation and the result is then been correlated to brain signal obtained. Thus the study of effect of aromatherapy covers the physiology and psychologically effects which are important to be identified to know the significant effect of aromatherapy to physiology and psychological as well as to determine the correlation between physiology and psychological of the human body. In this study, Rose has been chosen as the aroma for the study of the effect of aromatherapy.

In this study, we investigated the linearity/nonlinearity of mental activity electroencephalogram (EEG) signals for Brain-Computer Interface (BCI) designs using the recent but well established Delay Vector Variance (DVV) method. EEG data recorded from seven subjects while they were performing five different mental activities were used in the experimental study. Through the use of DVV, it was investigated whether EEG signals would become linear or nonlinear when segmented into smaller parts. Concluding, the results of the studies showed that a large percentage of the EEG signals exhibited non-linear behaviour. This is an important result as it shows that the currently used linear modelling methods are mostly unsuitable.

In this paper, a new method for characterizing the newborn heart rate variability (HRV) is proposed. The central of the method is the newly proposed technique for instantaneous frequency (IF) estimation specifically designed for nonstationary multicomponen signals such as HRV. The new method attempts to characterize the newborn HRV using features extracted from the time-frequency (TF) domain of the signal. These features comprise the IF, the instantaneous bandwidth (IB) and instantaneous energy (IE) of the different TF components of the HRV. Applied to the HRV of both normal and seizuresuffering newborns, this method clearly reveals the locations of the spectral peaks and their time-varying nature. The total energy of HRV components, ET and ratio of energy concentrated in the low-frequency (LF) to that in high-frequency (HF) components have been shown to be significant features in identifying the HRV of newborn with seizures.

Transform compression consists to apply an orthogonal transform on a window of the signal, and then proceed to reduce the number of bits representing transform coefficients. The simplest transform compression algorithm is one which eliminate the transform coefficients under threshold fixed a priori, this kind of algorithm is known as zonal transform compression system [5]. Applying this algorithm on ECG provides us a compression ratio of three (CR=3) approximately with an error ratio of five percent (PRD=5%) [3] [6]. In this paper, we develop a DCT compression algorithm for ECG, based on optimal bits allocation. The test results show that this method improve compression performances in term of compression ratio (CR) and the error percent ratio (PRD).

The wastes derived from oil palm industries are generated every year and becoming a great concern, consequently, an urgent development of bio-composting process has been investigated. Bio-composting is an environmental friendly bioconversion process where its products could be utilized as plant growth enhancement. In Malaysia about 50 million tons of Palm Oil Mill Effluents (POME) and about 40 million tones of Oil Palm Biomass (OPB) in forms of empty fruit bunches (EFB), oil palm trunks (OPT), and oil palm fronds (OPF) are generated from palm oil industries every year, the management practice pose significant environmental problems. This study was concerning about simple composting process using selected substrates, POME and EFB plus wheat floor as a co-substrate. The strains of P. chrysosporium, T. harzianum, A. niger (A 106, S 101), and Penicillium isolated from POME were used for effective bio-composting process. Tray bioreactor was used to evaluate the efficient composting process through solid state bioconversion. The composting time required to complete the process was two months and some parameters were determined to evaluate the compost quality. In the entire process merely, percentage of OM decreased to about 3% while total nitrogen content initially at 0.744 g/g increased to 2.96 g/g. The C/N ratio and GI achieved were 17 and 95 % respectively. The maturity of the compost could be reflected by C/N ratio, pH and GI measurement. The use of POME and EFB as mixed substrates with the induced microorganisms is a new composting trial where it has been expected to receive a good result in order to overcome a conventional composting process.

Four bacterial isolates from four different environmental samples (agricultural soil, compost soil and sewage sludge- anaerobic and aerobic wastewaters) were screened for their ability to mineralize 2-methoxyethanol under aerobic conditions. Isolate from anaerobic sewage wastewater was most efficient with an average of 48.6mmol/day mineralisation capacity. Morphological, physiological, biochemical and molecular characterization of the isolate showed that the strain, designated VB is of the genus

Pseudomonas

. 16S rRNA sequence analysis showed that the organism is related to

Pseudomonas putida

at 99.9% and

Pseudomonas plecoglossicida

at 99.8% similarity level. It is related to members of the genus

Pseudomomas

belonging to the rRNA group 1 within the gamma (γ)

Proteobacteria

. The G+C content 64.5±0.8mol% is within the range characteristic of the genus

Pseudomonas

. In a time course experiment

Pseudomonas

sp. strain VB was grown in 2-methoxyethanol, ethylene glycol, glycollate, glyoxylate, oxalate and methanol. Strain VB was able to utilize all proposed intermediates except methanol. Comparable growth characteristics of

Pseudomonas

sp. strain VB grown in 2- methoxyethanol and proposed intermediates showed significant molar growth yields. These results indicate that ethylene glycol, glycollate, glyoxylate and oxalate might be intermediates in the degradation pathway of 2-methoxyethanol. Thus a reaction sequence: 2-methoxyethanol → ethylene glycol → glycollate → glyoxylate → oxalate is been proposed in this study.

Glutathione

S

-transferase are a family of Phase II detoxification enzymes that catalyse the conjugation of glutathione to a wide variety of xenobiotics. To gain further insight into the relationship between structure and function of glutathione

S

-transferase, the four cystein mutants and the three Tyr108 mutants of hGSTP1-1 were expressed in

E. coli

and purified to electrophoretic homogeneity by affinity chromatography on immobilized GSH. The mutants were characterized that kinetic analysis and inhibition effects. The all cystein residues are not needed for the steroid isomerase activity of hGSTP1-1. The effect of substitutions on kinetic parameters suggests that Tyr108 in hGSTP1-1 contribute to the binding of the electrophilic substrate and a major determinant in the binding of CDNB in the aromatic ring of Tyr108, not its hydroxyl group. In order to search for bioactive natural products exerting inhibitory activity toward glutathione

S

transferase, twenty natural products extracts were screened for inhibition or activation of hGSTP1-1. As results, we found significant inhibition of GST by methanolic extracts of

Vucia unijuga, Sedum sarmentosum

and

Petasites japonicus

BUNGE.

The production of bioethanol was conducted by utilizing domestic wastewater sludge as major substrate using the yeast,

Saccharomyces cerevisiae

in liquid state bioconversion method (submerged fermentation). The optimum media and process conditions obtained from previous studies by using central composite design were applied in this study to evaluate the bioconversion process through ethanol production. The results presented in this study showed that 9.8% ethanol was produced utilizing sludge as substrate by

Saccharomyces cerevisiae

within 48 hours of fermentation while the COD, copper and chromium (heavy metals) removal were found to be 62%, 68% and 45% respectively in treated sludge after 72 hours of fermentation period. The total suspended solids (TSS) as biosolids (microbial growth) was observed to evaluate the microbial performance in bioconversion process. The observed yield and productivity were determined as well.

Oil palm industry has an important role in contributing to the Malaysian economy. Several million tonnes of crude palm oil is produced annually and approximately, about 10 million tonnes of palm oil mill effluent (POME) (highly polluted organic effluent) is generated every year. Citric acid is a commercially valuable product widely used in many industries. More than 400,000 tonnes of citric acid is produced annually by fermentation of expensive raw materials like glucose and sucrose. Efficient and effective methods of producing citric acid from different cheaper raw materials have been of great interest to many researchers, due to its extensive use. This study is an effort to achieve the goal by introducing a new substrate POME and a potential isolated strain of

Asperillus niger

. The method used was liquid state bioconversion with optimum process conditions obtained from our previous studies using central composite design (CCD) from Minitab software. The optimized parameters were temperature, agitation rate, inoculum size and pH. Analysis has been done everyday up to seven days of fermentation. Performance of the developed process was evaluated on the basis of maximum citric acid (5.24 g/L), chemical oxygen demand removal (COD), total suspended solid (TSS) and removal of heavy metals (cadmium chromium and copper).

In this paper, an application of wavelets to basic cardiology research is described and statistically analysed. The continuous wavelet transform (CWT) is used to detect acute myocardial ischemia caused by occlusion of a coronary artery in animal experiment. The use of CWT may help to understand fundamental changes in heart electrophysiology underlying acute myocardial ischemia. Statistical analysis of wavelet transform results support hypothesed intra-QRS changes.

The production of bioethanol was conducted by utilizing domestic wastewater sludge as major substrate with the aid of yeast,

Saccharomyces cerevisiae

using liquid state bioconversion method (submerged fermentation). The optimization of process conditions such as temperature, initial pH, inoculum dosage and agitation was carried out by using the central composite design (CCD) formulated by a statistical optimization software MINITAB. Optimization of process conditions was done with different ranges of temperature, pH, inoculum sizes and agitations with fixed media compositions obtained from previous study. A polynomial regression model was developed to determine the optimum compositions. Several techniques such ANOVA, t-test, p-values were observed to evaluate the model as well as the optimization process. The maximum ethanol production (9.1% v/v) was found while model equation predicted ethanol production with 11.9% v/v using the optimum conditions: temperature of 33°C, pH of 7, agitation of 200 rpm and inoculum of 1%. The results indicated that the temperature was highly significant (p<0.01) followed by the pH (p<0.01), inoculum (p<0.05) and agitation rate (p<0.05). The coefficient of determination (R

2

) was 90.1% which satisfied the adjustment of experimental data in the model.

Telomerase is a specialized RNA-directed DNA polymerase that extends telomeres of eukaryotic chromosomes in most human cancer. To date, little is known about how telomerase is activated and controlled in cancer, although activation is thought to be involved in cancer cell immortalization. Telomerase is composed of two main subunits, the rate-limiting catalytic subunit, human telomerase reverse transcriptase (hTERT), and the integral template of hTERT, human telomerase RNA components (hTR). Also, the hTERT are phosphor-proteins and its phosphorylation is a prerequisite for the activation of telomerase. Thus, phosphorylation of hTERT by protein kinase represents an elemental and essential step in maintenance of telomerase activity. To regulate activation of telomerase, hTERT gene amplified from FLAG-hTERT cDNA was expressed with 6xHis residues in

E. coli

. The expressed hTERT was identified using hTERT antibody and purified by His-bind resins. Also, hTR gene was amplified from genomic DNA of HeLa cell and gained hTR by

in vitro

reverse transcription methods. After the purified 6xHis-tagged hTERT and the hTR was reconstitution, the reconstituted complex was phosphorylated. Then, the activated hTERT by protein kinases was detected by PCR-based modified TRAP assay. This study will be useful for developments of drug design targeting hTERT in anticancer therapy.

MRC5 are well-characterized human diploid fibroblast cell line approved for vaccine production. We have adapted measles, Rubella and Polio viruses for propagation in MRC5 cell lines. In this study, telomerase activity during different passages of this cell detected and traced. Stocks of MRC5 cells from passage 15 to passage 38 were monitored. Trace amount of telomerase activity detected in these cells using TRAP-PCR with gel based detection. A decreasing order of telomerase activity observed with the cell doubling number. In order to compare in more details the telomerase activity during cell passage and replicative senescence, it was reassayed with an ultra sensitive method of TRAP-PCR ELISA based method. While in gel-based method trace amount of telomerase activity decreasing with increasing passage number of cells were detected, in PCR-ELISA very lower detectable telomerase activity were observed. We think this could be because of low processivity of this enzyme.

This work introduces a blood image processing for detecting and classifying malarial parasites in images of Giemsa stained blood slides, in order to evaluate the parasitaemia of the blood. Generally blood images are made up of three different kinds of cells, red, white and blood platelets. Their dimension, shape and their color distinguish these. In malarial blood, the red corpuscles of vertebrates are infected by malarial parasites. The aim of this paper is to detect the red blood cells that are infected by malarial parasites using statistical based approach. Further evaluation of the size and shape of the nuclei of the parasite is also considered.

The paper presents detection of the vocal disorder suffered due to the reaction of antibiotics during the course of medical treatment by extracting pitch information of the speech. Extraction of pitch of the speech is an important task due to the presence of background noise. Primarily start and end points of speech is detected and thereafter pitch boundaries are recognized using autocorrelation technique. This paper emphasized on accurate end point analysis for detection of the vocal disorder suffered due to the reaction of antibiotics during the course of treatment by extracting pitch information in the phonetics of Indian regional Marathi language numerical.

Approach to the maintenance of Medical Equipment has changed substantially over the years. In 70s the major activity was limited to the repair of equipment whenever it failed. This is called breakdown Maintenance. It was unpredictable and hence unscheduled, tedious, also time and cost consuming. Preventive Maintenance practice slowly became prominent to overcome these difficulties. Through the years, medical electronic products are becoming increasingly reliable. Preventive Maintenance now demands beyond traditional requirements. Safety and Performance Inspection (SPI) or Performance Assurance is the present trend which meets these additional requirements. Performance Assurance is carried out with help of Performance Testers.

Reconstructing a nose in the event of an accident, birth or genetic disorder can improve the quality of human life. The biological structure of a human nose can be reconstructed based on a set of predetermined landmarks. This paper discusses the mathematics used in the reconstruction of a real human specimen extracted from the CT-scan data obtained from the Radiology Department, Universiti Hospital Kubang Kerian. Basically the triangulation technique is used in building the structural 2D and 3D outline of the nose. A recursive algorithm is then constructed to refine the triangular mesh using barycentric coordinates. The spline technique is then used to smoothen the nose outline before it is finally rendered to give a realistic effect.

In this paper, a new method for quantification of rigidity in elbow joint of Parkinsonian patients is introduced. One of the most known syndromes in Parkinson’s disease is increased passive stiffness in muscles, which leads to rigidity in joints. Clinical evaluation of stiffness in wrist and/or elbow, commonly used by clinicians, is based on Unified Parkinson’s Disease Rating System (UPDRS). Subjective nature of this method may influence the accuracy and precision of evaluations. Hence, introducing an objective standard method based on quantitative measurements may be helpful. A test rig was designed and fabricated to measure range of motion and viscous and elastic components of passive stiffness in elbow joint. Measurements were done for 41 patients and 11 controls. Measures were extracted using Matlab-R14 software and statistic analyzes were done by Spss-13. Relation between each computed measure and the level of illness were analyzed. Results showed a better correlation between viscous component of stiffness and UPDRS score compared to the elastic component. Results of this research may help to introduce a standard objective method for evaluation of Parkinson’s disease.

The development of data-mining applications such as classification and clustering has shown the need for machine learning algorithms to be applied to large scale data. In this paper we present the comparison of different classification techniques using Waikato Environment for Knowledge Analysis or in short, WEKA. WEKA is an open source software which consists of a collection of machine learning algorithms for data mining tasks. The aim of this paper is to investigate the performance of different classification or clustering methods for a set of large data. The algorithm or methods tested are Bayes Network, Radial Basis Function, Pruned Tree, Single Conjunctive Rule Learner and Nearest Neighbors Algorithm. A fundamental review on the selected technique is presented for introduction purposes. The data breast cancer data with a total data of 6291 and a dimension of 699 rows and 9 columns will be used to test and justify the differences between the classification methods or algorithms. Subsequently, the classification technique that has the potential to significantly improve the common or conventional methods will be suggested for use in large scale data, bioinformatics or other general applications.

Recent genome-wide analysis of alternative splicing indicate that 40–60% of human genes have alternative splice forms, suggesting that alternative splicing is one of the most significant components of the functional complexity of the human genome. Avatar (A value added transcriptome database) identified 174,546 alternative splicing events coverage of Homo sapiens through an analysis of large scale ESTs. And Single nucleotide polymorphisms (SNPs) are the most abundant form of human genetic variation. The refSNP (reference SNP) of dbSNP contained a total of 9,098,790 refSNPs information. The large volume of data produced by high-throughput sequencing projects is a rich and large source of SNPs and alternative splicing. The study of alternative splicing has long been a valuable subfield of molecular biology, can promote the proceeding of molecular biologic studies. We analyze more than 100,000 alternative splicing events from Avatar, producing 15,228 candidate SNPs that probable have relation between SNP and alternative splicing. We use Fisher’s exact test to confirm the result and find 1,122 significant SNPs. Further we analyze the sequence in the area that near the alternative splicing event related SNP. We find some consensus sequences in the area, which may related to alternative splicing events.

The development of microarray-based high-throughput gene profiling has led to the hope that this technology could provide an efficient and accurate means of diagnosing and classifying cancers. However, the large amount of data generated by microarrays requires effective selection of informative genes for cancer classification. Key issue that needs to be addressed is a selection of small number of informative genes that contribute to a disease from the thousands of genes measured on microarrays. This work deals with finding the small subset of informative genes from gene expression microarray data which maximize the classification accuracy. We introduce an improved version of hybrid of genetic algorithm and support vector machine for genes selection and classification. We show that the classification accuracy of the proposed approach is superior to a number of current state-of-the-art methods of one widely used benchmark dataset. The informative genes from the best subset are validated and verified by comparing them with the biological results produced from biology and computer scientist researchers in order to explore the biological plausibility.

A novel power supply for medical implants has been developed. Using wireless technology secondary battery of power supply for implanted devices is recharged using laser diode, which transmits power in near infrared region. Transmitted power is received by photo voltaic cell array embedded under skin and charges the secondary battery, which in turn charges primary battery providing power to the implanted device. Experiments carried out have shown that, a photo diode with surface area of 2.1 cm

2

, emitting light in near infra red region at 810 nm wavelength with power density of 22 mW/cm, provides sufficient energy within 17 min to allow regular commercial cardiac pacemaker to work for 24 hrs. During continuous irradiation for 17 min on skin, temperature rise is only 1.4°C which is acceptable. Thus this wireless technique can be implemented for the benefits of patient.

This paper proposes a portable and potentiostat and further exerts the potentiometric pH sensing to verify its performance. The proposed potentiostat can process the real-time measured electrochemical data can be saved temporarily to the compact flash memory card or USB disk, and then can be transferred to a PC server through USB interface. Our experimental results indicate that the proposed potentiostat has several advanced features, such as moderate accuracy, low cost, and long-term data storage capability.

Surgery procedure today often relies on complete technical equipment. This will increase the important of usability as a selection criterion when hospitals purchase new equipment. In anorectal surgery, anal retractor are so important in ensure better visual field for operation, saving time and labour, with safety and reliability. Current retractors are working well but to a certain extend, it does not really offer certain ability that surgeon required. Surgery assistant especially facing a problem making a rotating movement on current retractors. With this point, an involvement of Industrial Design in the design and development process or concurrent engineering is a must.

The development and evaluation of medical devices from users’ perspectives requires the involvement of actual end users of medical devices. This kind of involvement of end users may not be always possible. A solution to this may be employing surrogates of end users. Nevertheless, this requires the identification and classification of appropriate surrogates. The study undertaken below reviewed relevant literature and suggests a taxonomy of surrogates of end users of medical devices. The taxonomy will be helpful in planning and making decisions in relation to the involvement of such surrogate users in developing and evaluating medical devices from the users’ perspectives.

We are developing an innovative miniature ambulatory hot flash recorder that is precise, accurate, reliable, affordable and aesthetically appropriate. It is a small disposable adhesive patch with two electrodes. A nondisposable, miniaturized, coated circuit board snaps onto the electrodes. The unit records the frequency, timing, and amplitude of hot flashes by measuring skin conductance, using no external wires or telemetry. The recorder contains a hot flash event marker that the subject triggers whenever she experiences a hot flash. Because hot flash skin conductance changes slowly, we measure every 10 s. We use pulsed waveforms to take the data, and sleep mode to conserve battery life. Since electrodes polarize if current always travels in a single direction, we use pulses in alternate directions. Data are downloaded directly from the patch to data acquisition software for computer display. The new recorder will be a valuable tool for researchers.

Current flow pattern simulation in the left ventricle (LV) requires method to tackle the interaction between the moving blood (fluid) and the deforming valves (structure). This fluid-structure interaction is the mechanism behind continuous cardiac activities. Capturing essence of these mechanics often involves solving complex mathematical equations which demands high computing resources. Limiting computing power has resulted in the need to optimize the degree of freedom (DOF) stemming from three-dimensional (3D) geometries. Many heart simulation projects aims to develop a 3D model for the reason that in three dimensional, the true motion of the heart muscle is better depicted. Unfortunately, higher DOF in 3D leads to difficulties in the equations modeling. For this reason, the complex equations, which in most cases derived from the differential domains; the partial differential equations (PDEs) and ordinary differential equations (ODEs), are usually modeled first on two-dimensional (2D) geometries. The focus of these prototypes is to ensure the equation modeling essentially captures the core of the fluid-structure interaction in the heart and enhancement of the prototype into 3D is usually done later to produce better graphical simulation.

In this research, the dynamic movement of heart valves and the blood flow pattern in the LV is studied using advanced numerical-computational technique. This approach is known as the Arbitrary Lagrangian-Eulerian (ALE) and is introduced by means of a mesh movement method in a finite element environment. The ALE uses two sets of reference systems; the Eulerian reference system to track the moving blood and the Lagrangian reference system to handle the deforming valves. A working prototype of the ALE model in 2D is developed and results pertaining to the velocity pattern prior to periodicity mechanics of the valves in the LV are presented graphically in a time-step fashion.

This paper will present our work on the planning and simulation of postoperative facial soft tissue prediction in the area of orthognathic surgery. We combine different methods of image processing, geometrical modeling and finite element analysis to predict and simulate the postoperative facial appearance of a malformed faced patient. Our approach is based on surface-based triangulation of the finite element method. The surgical planning system describes various preprocessing steps for the generation of 3D facial model and the surgery planning procedures involved. A number of procedures are highlighted during the preparation of facial model before the finite element analysis initiates. The prediction of the facial soft tissue is described based on finite element analysis through mathematical formulation by employing the linear elastic model. The surgical simulation results are shown, validated and discussed.

Arterial stiffness is known to be affected by aging, leading to changes in peripheral pulse propagation speed and shape. In this paper, the heart-finger segment of the upper- limb vascular system of six subjects in two age-groups (below 30 and above 55 years) is modeled using a modified Windkessel model. Actual left-ventricle pressure (LVP) data has been used as the input to the model. Circuit simulation results show a significantly higher amplitude for the dicrotic notch and a lower second peak in younger subjects. Among the older subjects, there was a gradual disappearance of dicrotic notch while the second peak appeared later. Comparison of the characteristics of the model output with measured peripheral pulse shows a good degree of conformity with the actual pulse signal. The parameters in the Windkessel model provide a simple, noninvasive means for studying changes in the elastic properties of the vascular system, depending on the age and potentially state of health.

Plaques have very complex structures. Real artery stenoses are rarely axisymmetric in the nature. This work is concerned with the simulation of plaque severity and eccentricity effects on arterial hemodynamic parameters in models of atherosclerotic carotid arteries with asymmetric stenoses using fluid-solid interaction (FSI). The parameters include wall shear stress, wall stress concentration and deformation. The investigation is done with the aid of finite element method for solving the structure and TDMA and SIMPLE methods in CFD for the fluid domain solution using ANSYS software. To overcome the software inconsistency in FSI mode, a new mathematical program is designed using incremental boundary iteration method. A linear elasticity approach is implemented in modeling the arterial wall and Navier-Stokes equations govern the fluid domain. Fluid separation zones, shear stress variation and fluctuation in the distal part of stenosis, minimum structural deformation, were observed under physiological and non-physiological conditions. Critical condition is determined due to severity variations which may lead to thrombus formation and possible plaque rupture. To illustrate the accuracy of proposed method, the results are compared with published experimental and numerical.

Background and purpose

: B-mode measurement of the sagital diameter of the Achilles Tendon (AT) based on manual tracing (MT) procedures is partly dependent on the subjectivity of the reader. The aim of this study is to compare the tracing results of the AT boundaries with an automatic identification (AI) process, already established for the detection of the Intima-Media-Thickness (IMT), and computerassisted MT.

Methods and Results

: The detection of the AT boundaries was performed in 115 US images of the AT including the anterior boundary of the calcaneus bone. The measured section (starting point 4cm away from the anterior boundary of the calcaneus bone) amounted 3 cm and was divided in 3 sub segments (1 cm each). Intra- and inter-reader/ - observer variability for the mean and the maximum AT Thickness (ATT) with AI and MT were evaluated. A normal group and a group with manifest tendinosis were compared concerning mean ATT (mATT) and maximum ATT (maxATT).

Using MT the intra- and inter-reader variability amounted 3.0 % and 6.8 %, respectively, using the AT 1.6 % and 3.9 % mm. Mean and maximum ATT were measured systematically lower by AI compared with MT in all regions by 0,4 mm. The AI procedure was most suitable in the 2

nd

segment. The mATT and maxATT were correctly detected in 93.9 % and 96.6 % of the images.

Conclusion

: The AI procedure detects the ATT with a high precision in all three segments. The most robust measurement was reached in the 2

nd

segment. It eliminates most of the inter-/intra-reader variability of the ATT measurement using MT. We suggest using the new method for new gold-standard of the ultrasound analysis of the AT.

The role of viscoelasticity of collagen fibers in articular cartilage was examined in compression and tension, using stress relaxation measurements in axial direction (normal to the articular surface). In this study, the degree of inherent stiffness anisotropy of completely-decomposed element was evaluated using finite element method. The model accounted for elastic deformations of the nanostructure in contact and assumed laminar flow in the created voids. The stiffness parameters from the laboratory tests were utilized in analysis which the elasticity of the solid phase was investigated in the present study. The results were suggested that the dominant mechanism for stress relaxation arose from fluid pressurization, while the associated relaxation in collagen fibers mainly was resulted in an increase in radial strain. Furthermore, Young’s modulus normal to the contact surface was increased from the superficial to the deep zone in articular cartilage.

In the year 1960 Hoffman and Cranefield have published the book “Electrophysiology of the Heart”. Since then a lot of research has been done, which makes it nearly impossible to integrate all discovered knowledge in one handy book for studying the nature of ECG. The relationship between the electrical excitation in the human heart and the body surface potential (BSP) is known as forward problem of electrocardiography. To enable the simulation of the electro anatomical function we coupled a cardiac model consisting of ventricles and atria. For studying the nature of ECG for the sinus beat, arrhythmias, ischemia and infarction this model can be used, and, furthermore, the model was used for developing and verifying electrocardiographic inverse approaches. The simulation toolbox was implemented in AmiraDev 3.0™, which is mainly a visualization-tool that can be expanded with self-developed plug-ins.

Ayurveda is an ancient form of Indian medicine. One of the techniques used for diagnosis of various diseases in this system is the ‘3-point pulse’ technique. A training module is proposed which simulates these three pulse points on a dummy arm. An electromechanical setup is developed using DC motors. Frequency and Amplitude characteristics of the human pulse are accurately reproduced by the simulator. A calculated input to the motors is provided through a micro-controller based GUI front end. Application extensions for telemedicine and remote patient monitoring are also discussed.

Bioimpedance measurement was performed in vitro on a compartment model as part of the investigation for a non invasive procedure in diagnosing a compartmental syndrome (CS). A model was constructed to mimic the body compartment of a lower leg. The cellular fluid of potassium ion (K

+

) of different concentration was prepared in vitro. The model was filled with K

+

solution and protein substances. Prior to the impedance measurement; pressure was applied within the compartment. This setup was to demonstrate physiologic events during CS. The impedance of the compartment at various concentration of K

+

, protein and pressure were measured with a commercial tetra polar bioimpendance analyzer. The results obtained from this investigation had shown positive correlation as predicted.

A microsphere-based detoxification system (MDS) [1,2] is an adsorption system, whereby microadsorbent particles having diameters of 1–20 µm circulate in an extracorporeal filtrate circle. A thin-wall hollow-fiber membrane filter separates the microparticle-plasma suspension from the bloodstream. For patient safety, it is necessary to have a means to detect membrane ruptures that could lead to a release of microparticles into the patient’s bloodstream, causing critical side effects. A non invasive optical detection system was developed to monitor the extracorporeal venous bloodstream for the presence of released microparticles. For detection purposes, polymeric microspheres, both ferromagnetic and fluorescently labeled, are suspended with the adsorbent particles. In the case of a membrane rupture, the labeled particles would be released together with the microadsorbent [2]. A high effective magnetic trap collect the ferromagnetic marker beats in the focus of an optical fluorescence detection device where the signal output is proportional to the trapped amount of labeled particles. A simulation model based on fluidic, gravitational and magnetic forces was developed to analyze the motion and sedimentation of the marker particles in the magnetic trap. The simulation results show excellent accordance to the laboratory experiments.

The temperature model of therapeutic ultrasound for human tissue is important in order to design an accurate instrumental assessment and calibration of therapeutic ultrasound device. The focus of this study is to verify temperature effects of ultrasound on tissues and explore the possibility of proposing a preliminary temperature model. A series of experiment had been conducted to clarify the relationship between output intensity and site of target tissue with temperature change in a phantom-tissue model for 10 minutes exposure of 3 MHz therapeutic ultrasound. It was found that 3 MHz ultrasound provided effectual heating at the superficial tissue, which is 1 cm from surface. It was also found that the experimental data had provided the necessary evidence for the development of preliminary temperature model. The temperature model had been produced by selecting suitable trend line for the graph of experimental data particularly for the temperature change at site of 1 cm from tissue surface. In conclusion, the preliminary finding of this study is the temperature effect of therapeutic ultrasound in homogeneous phantomtissue model has a suitable pattern to be modeled into a simple mathematical equation. This study also proposed further study to develop more reliable and holistic evidence-based temperature model.

In the study of physiological effect influenced by alcohol, the measurement of alcohol concentration is one important part of the researches. The efficient, accurate and convenient measurement tools are relatively under consideration. In this study, the regular blood tests, respiratory type alcohol examines, and Heart Rate Variability (HRV) were used to compare with the bioimpedance data in human body. The feasibility study was applied to record the ECG data from the human body with the analysis of the LabView 7.1 (National Instruments) and DAQPad 6020E (National Instruments). The bioimpedance data measured from the from left hand to right hand was recorded and analyzed by our bioimpedance measuring system and the MATLAB software version 6.5. All the electrophysiological parameters were analyzed with statistic software. In the result, the Heart Rate Variability (HRV) was significantly different in some subjects after alcohol consumption. However, there were no significant different in the bioimpedance measurement.

Our perceptive of the scientific datasets has largely relied on numerical and statistical analysis of data from experimental dimension and computer simulation result [4][14][11][12][13]. In particular, we consider a simulated 3D time-varying model of scientific datasets and examine the temporal correlation among datasets. Our goal is to contrive effective visual representations to assist scientists in ascertaining temporal correlation among intricate and apparently chaotic scientific datasets. We propose a hybrid application with combination of streamline, global and local color scale and opacity scheme for spatio-temporal collaborative depiction. We illustrated also few images that can offer an effective tool for visually mining 3D time-varying scientific datasets.

Development of a new steerable electrode array with embedded nitinol shape memory alloy actuators is described in this paper. The risk of damaging the basilar membrane during insertion of electrode array into the human cochlear is expected to be significantly reduced with the ability to redirect the tip of the electrode array at the critical hook region. The final position of this electrode array can also be adjusted to lie beneath the basilar membrane inside the scala tympani for delivery of neurotrophins (growth factors). The bending behaviour of the steerable electrode array and its trajectories during insertion into the scale tympani were predicted using a 3D finite element model. Results from the model have shown that the new electrode array can be steered through the critical ‘hook’ region and be accurately positioned for delivery of neurotrophins.

This machine is developed to replace a conventional ankle stretching device (ASD) consisting of wooden wedges with a microcontroller-controlled electro-mechanical actuators. An ASD has been used for lower limb rehabilitation treatment system for training of monoplegia (hemiplegia) patients for a long time. The developed training machine can control the angle between foot and calf (AFC), holding time, and the number of repetition. The machine consists of an embedded control unit (ECU) and a main control unit (MCU). The application program running on the MCU controls the overall operation of the system, it sends commands to the ECU to get proper functions, and receives status of the ECU. The ECU consists of two clinometers, a 12-bit serial ADC, a lowpass filter with cut-off frequency of 1Hz, microcontroller, RS- 232 serial interface with the MCU and electro-mechanical actuators. It can reduce the work of physical therapist and improve the effect of rehabilitation exercise.

Due to damaged vertebrae nerves, serious disease and aging, patients who have to lie down for long period of time need to exercise to maintain up-right standing position and recover their paralytic leg. This study describes a development of an intellectual tilt table which can provide a patient with rehabilitating condition. This can be possible by measuring and displaying the knee bent angle and pressure for each foot during exercise in real time. It is expected that the patient’s exercising effect can increase by monitoring these two values during exercise.

Background: To improve the computer operation for people with severe disabilities, more flexible pointing devices are required. This study investigates the effectiveness of a new developed Integrated Pointing Device Apparatus (IPDA), that can integrate numerous commercial pointing devices, for people with severe disabilities.

Methods: We collected 20 children with quadriplegic cerebral palsy (CP) and 25 people with high cervical spinal cord injuries (SCI). People with disabilities were classified into 2 groups based on pointing device used: group A1 (SCI) or A2 (CP), who used standard mice, and group B1 (SCI) or B2 (CP), who were unable to use standard mice (IPDA combinations). All subjects received clinical severity and three specific mouse-operating efficiency assessments (continuous clicking, target-acquisition, drag-and-drop tasks). The efficiency of the people with disabilities in each mouse-operation task was expressed as a percentage of that for able-bodied subjects (%NL). The level of statistical significant was set at a value of

P

less than .05.

Results: Group B1 or B2 displayed similar operational efficiency in performing the drag-and-drop tasks to group A1 or A2, although they exhibited worse efficiency than group A1 or A2 in performing the continuous-clicking tasks (

P

<.05). The use of pointing devices was associated with American Spinal Injury Association Impairment Scale of people with SCI, and Gross Motor Functional Classification System (GMFCS) of children with CP (

P

<.05).

Conclusion: The IPDA could help most people with severe disabilities who could not utilize commercial mice to achieve acceptable operational efficiencies. Pointing devices were assigned based on the underlying severity.

People with neurological disabilities that affect their lower limbs are usually less active and have reduced aerobic fitness compared to their able-bodied cohorts. For this population to increase their functional capacity, proper training regimes have to be prescribed, which suit the nature of their injury and maximize their exercise capacity. One popular technique is to use functional electrical stimulation (FES) leg exercise for the weak or paralysed muscles. This paper describes the conceptual design of a new isokinetic FES leg stepping trainer for individuals with neurological disability. The combination of seated elliptical-motion stepping, FES and isokinetic exercise has the potential to improve rehabilitation outcomes in persons with lower limb paresis or paralysis. The proposed exercise machine can offer safe and intense training that is relevant to walking.

A development of a wireless heart rate monitoring system for rehabilitation patients who are taking physical therapy inside a rehabilitation center is discussed in this paper. The purpose of this study is to develop a monitoring system that can monitor patients’ heart rates so that it gives physical therapist early warning if necessary. The whole system consists of the patient’s side device (PSD) and central monitoring system (CMS). The PSD was designed to be wearable and low power consumption. The CMS was designed to monitor multiple patients simultaneously and generate a warning signal if necessary. The CMS and PSDs are linked by a wireless network proposed in this study.

The purpose of the study is to develop a prosthetic hand that able to perform the four essential tasks: cylindrical grasp, key pinch, pulp to pulp pinch and tripod pinch. The human hand could be considered as a linkage system of the intercalated bony segments. Therefore, prosthetic fingers and thumb were often modeled as a planar three-link open chain each, whose plane of motion was defined by yaw at the base joint. All the four fingers were modeled the same exclude for the lengths of each segment, and arranged parallel to one another on the

xy

-plane. All fingers maintain the same size due to assumptions that normal hands maintain similar anatomical structure and dimensional proportion, regardless of their sizes. The hand was modeled so that it will form an equiangular motion path and reach an optimum working space to meet the objective of the study. An experiment to observe the fingertip trajectory and stability of movement for each finger was carried out using motion analysis equipment available in the Motion Analysis Laboratory, Department of Biomedical Engineering, University of Malaya.

Brain machine interfaces provide a digital channel between the brain and the physical world. Electrophysiological signals such as EMG, EEG, and EOG of the brain can provide a non muscular channel to control external devices. In this paper we present a survey on Electroencephalogram [EEG] based brain machine interfaces [BMI] and the feasibility of a brain interface to control wheel chairs. With the advent of noninvasive electrodes, research in EEG has been directed towards development of brain machine interfaces to replace damaged motor nerves. Restoring complex motor functions like reaching and grasping still remains a major challenge. This paper presents a preliminary study on using EEG signals for rehabilitation and the current research on EEG based BMI.

The deficiency of expressing symbol ability of the spoken language for articulation disorder will leads to the difficulty of verbal expression and communication. In the clinical protocol, language therapist subjectively utilizes the clinical experience to individually test and treat articulation disorder. The manpower of language therapist and the computer based assistant instructions are also insufficient. In this paper, an articulation training system with automatic pronunciation detection mechanism is proposed to assistance in the program of language treating for language therapist. The articulation errors in phonetic level are analyzed and modeled by clinical linguist. According to the articulation errors, a speech recognition based automatic pronunciation detection algorithm is developed to effectively acquire use’s pronunciation characteristic. Speechreading based feedback responses are designed and applied to improve the efficiency of training program. Preliminary results reveal the practicability of our proposed method and system.

Functional electrical stimulation (FES) is the use of electrical currents to artificially evoke muscle contractions, thereby producing human limb movements. FES is widely used amongst people with paralysis either as an exercise strategy or for daily functional applications. This paper presents an insight into one FES application — FES evoked cycling for people with spinal cord injury (SCI). Published research and peer opinions are presented to provide an understanding about the topic and to identify the benefits, technological aspects, as well as the limitations and challenges of FES cycling after SCI.

The objective of the study is to develop a prosthetic hand for the usage of Brain-computer Interface (BCI) system. In the proposed BCI system the prosthetic hand was introduced as an external device controlled by the system. This hand is required to perform four essential tasks of the human hand: cylindrical grasp, key pinch, pulp to pulp pinch and tripod pinch. The hand was inspired by the perfection and complexity of the human hand. This hand consists of palm and 5 fingers with a total of 16 degrees of freedom (DOF). The phalanges of each finger was modeled as three link open chain joined at the metacarpal joint (MCP), proximal joint (PIP) and distal joint (DIP). Phalanx was made from two identical parallel aluminum plates and connected to the other segment using a bolted spacer acting as hinge joint. The Length of each segment was made such that it will form an equiangular motion path during trajectory. Each joint is actuated by its individual actuator. Two mechanisms were proposed in this study. The first mechanism is the tendon drive; used terelyne string to pull each segment to flexion. The second mechanism is a spring return; a stored resistive force in torsion spring will kick the segment to its initial position. The hand was equipped with potentiometers and force sensors for control purposes. The prototype of the prosthetic hand was tested with BCI system, in order to meet its initial objective and additional tests were carried out to evaluate its performance. An experiment to test the performance of the prosthetic hand was carried out successfully. Strength of each tendon was measured using a proof ring method and motion images were captured using video camera and analyzed using Peak Motus 7 Motion Analysis software.

Quadriplegic Communicator is designed to provide a communication tool between the quadriplegic patients and their care provider. The system is developed based on user-friendly concept and involved hardware and software integration. The acquisition circuit is able to capture rapid signal response from eye and send signal to the computer through a parallel port. The eye-blinking signal which was received in the reflective sensor will be amplified, filtered, generate a TTL signal to be acquired by the computer and able to be detected through Visual Basic program. Since this tool is expected to be used for Malaysia’s citizen, the software GUI is designed in three languages selection. This system will be able to display the message that is selected from user and play the related message in sound.

The key joint of the forefoot during gait is the first metatarsophalangeal joint. It is subject to high loads and plays an important role in propelling the human form. Unfortunately the first metatarsophalangeal joint can be subject to a number of diseases, such as rheumatoid arthritis, hallux rigidus and hallux valgus, all of which can lead to replacement of the natural joint with a prosthesis. Most commonly, a silicone spacer might be implanted but other designs are available which more closely try to match the natural joint by employing a two-piece ball and socket arrangement. Such designs are available with a range of biomaterial couples including ceramic-on-ceramic, metal-on-metal and metal-on-polymer. Calculation of predicted lubrication regimes applicable to these implant designs was undertaken. Modeling the ball and socket implant as an equivalent ball-on-plane model and employing elastohydrodynamic theory allowed the minimum film thickness to be calculated and in turn the lambda ratio to indicate the lubrication regime. Boundary lubrication is indicated for lambda less than 1, mixed lubrication for lambda between 1 and 3, and fluid film lubrication for lambda greater than 3. The calculations were undertaken for a 10 to 1500N range of loading values, a 0 to 30mm/s range of entraining velocities, and a 3 to 15mm radius ranger of sizes. Calculations showed that, for the range of loads, sizes and entraining velocities considered, the ceramic-on-ceramic and metal-on-metal implants could operate under fluid film lubrication, whereas the metal-on-polymer combination operated in the boundary lubrication regime. It was also recognized that manufacturing capabilities are critical to the radial clearances and values of surface roughness that can be achieved, and thus the predicted lubrication regime. Inevitably, a range of factors need to be considered when designing or choosing an implant for the first metatarsophalangeal joint.

In this paper, the prototype of the tele-ultrasound consultation system has been designed and evaluated over digital subscriber lines including ADSL and VDSL. The ActiveX control, and software-based MPEG-4 and H.320 CODECs (Coder and Decoder) allowed low-cost, flexible, Web-based, and real-time implementation for interactive teleconsultation through general Web browser. Specifically, the features of designed sysem are usablity of the MPEG-4 coding of full-resolution ultrasound video, accessibility via Web browser, combined transmission of ultrasound video with video conferencing in real-time, and operability over cheap ADSL, and VDSL lines. The quality of ultrasound images in terms of compression ratio and frame rate were measured using patients’ data to evaluate the performance of the designed system over DSL lines, and to demonstrate usability for practical use.

This paper is a progress report on the development of a mobile telemedicine system with multi communication links. The system design goal is to provide patient monitoring during the prehospital transport and to offer health services, for people who lives in underserved areas. Therefore, medical information transmission becomes very crucial, since there is no a transmission link stability guarantee. To deal with this issue, multi communication links, which including VHF radio, internet, GSM/CDMA mobile phones, and GPRS are applied for the system. Selection of the communication links depends on the availability of the local communication infrastructure.

To implement the system functions, a functional unit called a telemedicine arbiter is being designed. This unit consists of a medical information concentrator module and a communication manager module. Communication link selection scheme is developed based on the result of the signal quality survey in a target location. To provide the scheme, a dedicated software is developed.

Currently, the research is focused on the development of a software for data transaction which is based on a client-server model. Moreover, an enhancement of the telemedicine arbiter unit is also being conducted. Finally, a number of test fields to transmit medical information has been implemented as well. The results are promising, although some improvements are still required, in particular to alleviate a problem in no signals coverage areas.

Most biologists keep data in separate databases created themselves. These databases are not well-structured. Plant identification keys are among such data. They are used to identify various plant species. The way the data is kept often requires the species identification to be done linearly. Done manual, this is very time consuming.

Information extraction (IE) is a process of selecting information such as names, terms, or phrases, from a natural language text documents. This information is then structured into a specified template for easy retrieval. This method is applied to plant identification keys kept by the biologists. We illustrate the processes using an example from a database and discuss ways to reorganize the identification keys.

This paper presents the results from a two month-long study of a group of people participating in an online health-community on overweight. The relation between their contributions in the community and their experienced weight change was investigated. The results show a tendency towards that the greater weight loss the community members experienced the more active they were in the conversations. When focusing on the online discussions more specifically concerned with learning problems, this relation was even more evident.

Utilizing salt leaching method, a composite maaterial of PCL (Poly ε-caprolactone) and HA (Hydroxyapatite) particles was suggested as a potential scaffold for bone tissue engineering. For this, composite materials were prepared with various HA contents (20wt%, 40wt%, 60wt%). To ensure the potential for the scaffolds, porosity, mechanical stiffness, proliferation tests were conducted along with SEM observations. The addition of HA particles enhanced proliferation of MG-63 during the test. Also, the mechanical stiffness was increased as HA particles were added. Even the porosity was decreased as the contents of HA particles was increased, the porosity of the composite with the highest contents of HA was still adoptable (∼85%). From the study we conducted, addition of HA particles to PCL showed promising results. However, further studies are needed such as long term tests for osteoconductivi-ties, regeneration of extracellular matrices, and differentiation utilizing BMSC (bone marrow stromal cell) with animals.

Novel Surface Selective Laser Sintering (SSLS) technique enable precise fabrication of complicated 3D composite biodegradable scaffolds from thermosensitive polylactic and polylactic-co-glycolic acids and even retain bioactivity of incorporated enzymes. The presence of carbon black (CB) nanoparticles in SSLS structures raised concerns about their toxicity and biocompatibility. In present paper we studied this by diverse

in vitro

analysis using 3T3 fibroblasts, ovine meniscal chondrocytes and C2C12 myoblast cell cultures. All cells “readily” attached to and proliferated on CB containing surfaces. The abundance of live cells spreading out and covering the entire SSLS porous structures confirms their high biocompatibility. Moreover, C2C12 cells in the presence of morphogenetic protein rhBMP-2 have shown strong shift in differentiation pathway from myoblastic to osteoblastic type. These promising results encouraged us to further development of SSLS methodology targeted to custom-designed biodegradable scaffolds and implant fabrication.

In this study, a new material which is collagen/ poly (ethylene oxide) (PEO) blend was developed to determine its possibility as a promising material for tissue scaffold. PEO with average molecular weight of 600,000 and collagen originated from calf skin were dispersed in 0.1 M acetic acid to prepare a concentration of 1 wt% for PEO and 0.15 wt% for collagen. The collagen-PEO600K blend film was then obtained by solution casting method. The morphology and the phase structure of the blends were studied using SEM and XRD. SEM results shown that by having certain ratio of collagen and PEO, the membrane began to developed porous structures which are possible to assist tissue attachment on the scaffold. The X-ray diffractograms demonstrate PEO 600K influences on the blend thus enhancing crystallinity of collagen which explained the membrane morphological structure. Therefore, we concluded that the crystallinity of PEO in the blend is crucial to produce desirable morphological structure of the membrane which is required for a reliable tissue scaffold.

Articular cartilage extracellular matrix (ECM) plays a crucial role in regulating chondrocyte functions via cell-matrix interaction, cytoskeletal organization and integrinmediated signaling. The effects of transforming growth factor-β (TGF- β) and β-estradiol on extracellular matrix have remained controversial in chondrocyte studies though it has been proven that cartilage responds to these factors

in vivo

. In our study, we examined the effect of these factors on modulating glycosaminoglycan secretion. Articular chondrocytes from rabbits were cultured, and the effects of supplementing 10ng/ml of TGF-β, 10nM of β-estradiol, and a combination of both factors were compared. The synthesis of sulphated glycosaminoglycan (GAG) was shown to be enhanced in the TGF-β treated cultures and when TGF-β and β-estradiol were both used. However, β-estradiol does not appear to affect GAG deposition.

Introduction

: Treatment of soft tissue defects requires the generation of a long-term stable tissue construct which resides in an equilibrium with adjacent anatomical structures. Histioconductive approaches use biocompatible and -degradable scaffolds seeded with tissue- and host-specific precursor cells which are implanted at desired loci. Those scaffolds act as a temporarily nutritional extracellular matrix which guide tissue formation by ensuring cell-cell and cell-matrix interactions. We investigated whether hyaluronic acid scaffolds could be used as biocompatible scaffolds to generate an adipose tissue construct in vivo.

Materials and Methods

: Twelve volunteers (20 to 35 years) were included. Lipoaspirate was obtained with consent through the Department of Plastic Surgery with approval from the Human Ethics Committee. Isolated preadipocytes were expanded and seeded (0.5×10

6

cells) on hyaluronic acid-based biodegradable polymeric scaffolds (HYAFF11®). Four days later the engineered bio-hybrid (ADIPOGRAFT®), seeded with autologous preadipocytes, and a cell-free control scaffold were implanted subcutaneously. Three time courses (2, 8 and 16 weeks) were set up with each group consisting out of four volunteers. Harvested specimens were analyzed using standard histology and immunohistochemistry.

Results

: There were no adverse effects with both cell-seeded and non-seeded scaffolds being well tolerated. Considerable volume loss of the non-seeded scaffolds was observed compared to the cell-seeded group, indicating progressive integration and biocompatibility of the latter within the host.

However, histological analysis showed no consistent or clear differences between the adipograft samples and the HYAFF11® unseeded scaffolds. Implanted materials were incompletely infiltrated with cells at 2 weeks but by 8 weeks all void spaces were filled with cells with considerable deposition of extracellular matrix.

Conclusion

: This clinical trial concludes that hyaluronic acid scaffolds are biocompatible, stable cell-carriers to be used for tissue engineering purposes in humans. Further research will identify crucial cues which need to be considered to enhance preadipocyte survival with subsequent differentiation.

The objective of this study is to investigate the potential of dual-electrospun polymer based structure for vascular tissue engineering, especially for the medium or small size blood vessels. Polyurethane(PU), which is known to be biocompatible in this area, was electrospun along with poly(ethylene oxide) (PEO). Concentration of PU was fixed at 20wt%, while that of PEO was set from 15 to 35wt%. Morphological observation (SEM and porosity) and cellular responses were tested before and after extracting PEO from the hybrid scaffolds by soaking the scaffolds into distilled water. The diameter of PEO fibers were ranged in 200≈500nm. The lower concentration of PEO tended to show beads. The porosity of the scaffolds after extracting PEO was highly increased with higher concentration of PEO as expected. Also, higher proliferation rate of smooth muscle cells was observed at higher concentration of PEO than at the lower concentration and without PEO. As conclusions, this dual electrospinning technique combined with PU and PEO is expected to overcome the current barrier of cell penetration by providing more space for cells to proliferation.

The construction of stable engineered tissue depends on the formation of a functional connective tissue produced by cells locally. A major component of connective tissue is collagen. Its deposition into a stable matrix depends on the enzymatic extracellular conversion of procollagen to collagen. This step is very slow

in vitro

and we hypothesized that this is due to a lack of crowdedness and insufficient excluded volume effect (EVE) in culture media. We used neutral (670 kDa) and negatively charged dextran sulfate (DxS, 500 kDa) to create EVE in cell cultures and to enhance

in vitro

matrix formation by accelerating procollagen conversion. Biochemical analyses in two human fibroblast lines revealed mostly unprocessed procollagen in uncrowded culture medium, whereas in the presence of DxS, procollagen conversion occurred and most of the collagen was associated with the cell layer. Immunocytochemistry confirmed DxS-related collagen deposition that colocalized with fibronectin. The large neutral dextran showed in identical concentration ranges no effects which correlated well with its smaller hydrodynamic radius as determined by dynamic light scattering. This predicted a 10 times bigger crowding power of DxS and benchmarks it as a potentially promising crowding agent facilitating the formation of extracellular matrix

in vitro

.

To evaluate the ability of autologous chondrocyte transplantation to repair articular cartilage defects, autologous chondrocytes embedded in alginate beads were implanted in focal cartilage defects created in 9 New Zealand white rabbits. After 4 weeks of cartilage damage, the right knee was repaired via autologous chondrocyte-alginate constructs transplantation and the left knee was left untreated (control group). The quality of cartilage tissues of both knees was then compared at 3 months following the procedure, as reflected by the quantitative analysis of glucosaminoglycan (GAG) in the cartilage and histological examination of the tissue in accordance to the Brittberg scoring scale. Macroscopic examination showed better regeneration of the defective area following chondrocyte-alginate transplantation repair compared to the non-treated site. Biochemical analysis revealed significantly higher cellular expression of GAG in the treated knee as compared to the non-treated knee [1.12 ± 0.48 µg GAGs / mg protein vs. 0.81 ± 0.17 µg GAGs / mg protein, respectively;

p

=0.008]. The mean Brittberg scores was significantly higher in the treated knee as compared to control knee [6.00 ± 1.23 vs. 1.89 ± 1.54;

p

=0.007]. This result can be explained by the fact that chondrocytes cultured in alginate gel beads retained their ability to synthesize cartilage-specific molecules. The alginate beads were perfectly biocompatible with chondrocytes and surrounding cartilage tissue. These findings also indicated that chondrocyte-alginate transplantation has shown enhanced repair results compared to the nontreated measures.