1st Global Conference on Biomedical Engineering & 9th Asian-Pacific Conference on Medical and Biological Engineering

Biofouling generally causes adverse effects to health, such as thrombosis, infection, and pathogenic calcification. Hydrophilic and charge-balanced surface is proved to provide an energy barrier serving as a strong repulsive force against the nonspecific absorption. Unfortunately, the state-of-art technology for silicone modification cannot provide a stable and effective coating for the long-term applications under complex conditions. In this study, we aim to modify the silicone surfaces with a zwitterionic surface ligand to resist nonspecific adsorption of protein, lipid and bacteria. We synthesized a silanized surface ligand conjugated with a head residue of zwitterionic sulfobetaine (SBSi) that bears positively charged quaternary amine and negatively charged sulfonate groups. The bacterial adhesion tests and protein fouling test revealed the excellent antifouling properties of modified silicones. For the real-world application, we modified commercially available silicone hydrogel contact lenses with developed zwitterionic ligands and showed their capability of anti-bacterial adhesion and anti protein fouling. In summary, the strategy of surface engineering in this work can be applied to not only contact lenses but other silicone-based medical devices in facile and effective fashion.

Hyperthermia for the treatment of resistant tumors has been reported with promising results. Repeated treatment times and applicable for many kinds of cancers are the potential benefits of hyperthermia. Of note is that the success of intracellular hyperthermia is largely dependent on the development of an adequate heat mediator. In this work, we have successfully developed an intracellular hyperthermia system using magnetic hydroxyapatite (mHap) nanocrystals as a thermoseed. After surface modification, poly (ethylene glycol) (PEG) and hyaluronic acid (HA) modified mHap nanocrystals could not only be localized and accumulated in cancer cells, but also efficiently taken up by targeted tumor cells via HA receptor mediated endocytosis process. Furthermore, these Hap-based magnetic nanocrystals may also serve as a tracer for the diagnostic contrast agent under MRI and a drug delivery carrier for therapeutic applications in cancer therapy in vitro and in vivo.

One of the reason caused the production of scar is the excessive sediment or the overtime precipitation during the wounds healing. So far amount all the medical supplies, hydrocolloid dressings which used to repair the burn wounds and the normal trauma are bass on promotion of wound healing. Nevertheless there are no medical supplies combine hydrocolloid dressings with anti-pigmentation drugs; therefor our research has focused on preparing gelatin nanoparticle. First, prepared different size of particles by controlling the parameters. Second, loaded various concentrations of ascorbic acid into particles, analyzed the drug entrapment efficiency and the rate of drug release. Last, co-culture nanoparticle with fibroblast, research the effect of nanoparticle on the fibroblast, in order to prepare a successful anti pigmentation gelatin nanoparticle. Under distinct condition, particle size 150nm ~ 300nm of gelatin nanoparticle could be prepared, furthermore the effective concentration of ascorbic acid 0.3%~10% is successfully completed and the drug-loaded nanoparticles are able to extend the life-span of the fibroblast.

Liposome is by far the most successful drug delivery vesicle commercialized for clinical use, and can fundamentally modify the performance and clearance of encapsulated drug. The encapsulation of contrast medium of computed tomography in liposome could improve the lesion screening efficiency by EPR effect of liposome, and prevent the incidence of contrast medium induced nephropathy by shielding of liposome.

Nanomaterials is one of the areas most highly concerned about medical technology nowadays.Such as metal nanoparticles,nanorods,and so on.

Functionalized nanoparticles can be used as cancer probes, drug carriers to help us to investigate more research about biotechnology.

In this study,we synthesize different size metal nanoparticles and conjugate with Amine-Polyethylene glycol-Biotin (NH2-PEG-Biotin) to functionalize it. We can control the number of NH2-PEG-Biotin on the surface of nanoparticles successfully.

We believe the interaction of different size nanoparticles and different numbers of NH2-PEG-Biotin can improve the area for biomedical application.

Nanomaterials are commonly used in biomedical research, mostly in cancer diagnosis and therapy. In this study, we used dark-field hyperspectral systems to investigate nanomaterials for the biological interaction of the opsonized or pegylated nanomaterials. Gold nanoparticles have good biocompatibility and exhibit strong light scattering behavior under the dark-field microscope. Those properties make it feasible to study the interaction between the surface functionalized nanomaterials and cellular micro-environments multi-dimensionally.

Many researchers have found that the stability of SAMs is an issue for long-term biomedical applications. The surface functional group is not stable under ambient conditions. To address this problem, we use cysteine, natural sulfur-containing zwitterionic compounds, and cysteine betaine which is the derivative of cycteine, with quaternary ammonium group at its terminal end, to decorate Au substrate by using the chemisorbing properties of the thiol group. By adding various different additives into the solution of alkanethiols during SAM formation to eliminate unbound thiol and to prevent the degradation processes of alkanethiol SAMs, we can decrease the film thickness and increase the wettability. Furthermore, we also compared their physical and chemical properties of amino acids SAMs on Au that were stored under different conditions for various lengths of time. Based on the above, our study aims to investigate the influence of different SAMs condition and chemical structure for anti-fouling properties. Contact angle analysis indicated that after degradation, the photooxidation sample decreased relative to that of the freshly prepared SAMs. X-ray photoelectron spectroscopy (XPS) not only used to detect the chemical elements of SAMs on Au substrates, but also detect the changes in the chemical state of the surface oxidized atoms. The bacterial adhesion tests revealed the excellent anti-fouling properties of zwitterionic amino acids SAMs. And adopt MTT assay to assessing cell viability.

Use of synthetic biomaterials as blood-contacting devices typically accompanies considerable nonspecific adsorption of proteins, cells and bacteria. These may eventually induce adverse pathogenic problems in clinic practices, such as thrombosis and biomaterials-associated infection. An effective surface coating for medical devices has been pursued to repel nonspecific adsorption from surfaces. In this study, bio-inspired adhesive dopamine conjugated with zwitterionic sulfobetaine moieties (SB-DA) was developed for anti-biofouling properties. The molecules can anchor onto various substrates via catechol groups to form a stable thin film. The results indicated that the formation of self-assembled monolayers (SAMs) was strongly dependent on the pH values in preparation, which correlates to the oxidization and reduction (redox) of catechol groups in dopamine molecules. The Other mussel-inspired catecholic zwitterionic nitro-sulfobetaine moieties (SB-nDA) assembly possessing antifouling and photocleavable characters for spatiotemporal tailoring of interfacial properties and controlling bio-adsorption. X-ray photoelectron spectroscopy (XPS) was used to analyze the bonding mechanism, accounting for distinct wetting and fouling levels from contact angle and quartz crystal microbalance with dissipation (QCM-D) measurements. The thickness simulation from XPS and ellipsometry showed about 1.1 nm for intact SB-DA films and 1.03 nm for intact SB-nDA. In addition, the bacterial test indicated the excellent resistance of films against P. aeruginosa. This work provides not only new surface chemistry but the new route for surface modification. Currently, SB-DA is applied onto various materials with different dimensions as a new generation of self-assembling biomaterials for a wide spectrum of applications then SB-nDA for potential applications in light-guided targeting and releasing of drug delivery and molecular imaging.

In this work, a composited guided bone regeneration (GBR) membrane made of hydroxyapatite (HA) mineralized on electrospun chitosan (CS)-coated poly (lactic acid) (PLA) nanofiber mat was prepared and compared in terms of mineralization characteristics. Fabrication parameters of CS-co-PLA nanofibers and mineralized of calcium phosphate crystals were discussed in details. Fourier transform infrared spectroscopy (FTIR) showed a compositions of CS/PLA mixture and X-ray diffraction results further indicated that the composition of the deposited mineral was a mixture of dicalcium phosphate dehydrates and apatite. These results indicated the HA crystals can be simple mineralized on CS/PLA nanofiber mat which provides notonly better geometric properties but also biological functions for GBR application.

The purpose of this study was to develop kinds of multi-walled carbon nanotubes (MWCNT)-based materials, which could replace current autografts for neuron regeneration. The alternative MWCNT films was developed by encapsulated chitosan. To evaluate the characteristics of MWCNT films after modification, the measurements of electrical conductivity, contact angle and the degree of degradation were carried out. Two kinds of chitosan film preparation were designed, one was the dish film and the other was microscope slide film. The microscope slide film was exterior, however, the dish film was wrinkling. Comparing the thickness by micrometer caliper, the thickness of the dish film was 0.1950 to 0.0425 mm, and the microscope slide film was 0.0584 to 0.0109 mm. This result indicated the microscope slide film was more suitable for the following experiment because of less error value. The contact angle of the chitosan film was measured between 60~90 deg, it indicated the film was more hydrophobic. In order to achieve better biocompatibility, adding MWCNT significantly increased hydrophilicity of chitosan film.

We have synthesized and characterized a novel zwitterionic nanocomposite hydrogel as effective chronic wound healing dressings. The hydrogel is composited of nonfouling zwitterionic polymer as a major composition, plus small quantity of nano-sized clay for improved mechanical strength and in-situ formation silver nanoparticles for anti-microbial function. The novel zwitterionic nanocomposite hydrogel possesses unique features, including 1. biocmpatibility; 2. high water content; 3. anti-biofouling properties; 4. strong durability; 5. suppression of bacterial growth; 6. controlled release of Ag ions. These features allow developed formulation becoming extraordinary chronic wound dressing for clinical applications.The hydrogel was fabricated via a “one-pot synthesis” approach and the physicochemical properties were characterized detail. Moreover, the antifouling properties of hydrogels were evaluated in contact with a protein and bacterial solutions.

Gene delivery by non-viral vectors is limited by cytotoxicity. In this study, we transferred plasmid DNA into stem cells by seeding cells on substrates with different physico-chemical properties. Gene entry was facilitated by the activation of integrins and cell motility on different material surface. The finding could be used to screen materials that promote cell migration and endocytosis.

Diabetes mellitus is one of the most common diseases in the world and can causemany types of neuropathies, and even mortality. It is therefore important to understand how diabetes mellitus alters the mechanical properties of nerve tissues and their blood vessels. In this study, in situ compression-and-hold circular compression tests were applied to the sciatic nerves of both diabetic rats and normal rats. Doppler optical coherence tomography (Doppler OCT) was then utilized to monitor the configuration of the arterioles in two groups of rats. The force data acquired in the compression tests were fitted by using Fung’s quasi-linear viscoelastic model (QLV) to determine the viscoelasticity of the nerves. The results show that the nerves in the diabetic group had a longer relaxation time than those in the normal group. Consequently, the Doppler OCT observations reveal that in contrast to the normal arterioles, the diabetic arterioles did not dilate in the relaxation phase. The results of the force data integrated with the corresponding arteriole dilatation images may explain why the diabetic patients are more prone to carpal tunnel syndrome. The results may facilitate developing new approaches for treating diabetic neuropathy and for nerve repair and regeneration.

In the context of biological applications, the timely delivery of molecules can be critical for cellular and organ function. As such, previous studies have demonstrated the superior long-term protein delivery, by way of protein tethering onto bioengineered scaffolds, compared to conventional delivery of soluble protein

in vitro

and

in vivo

. Despite such benefits little knowledge exists regarding the stability, release kinetics, longevity, activation of intracellular pathway and functionality of these proteins over time. By way of example, here we examined the stability, degradation and functionality of a protein, glial derived neurotrophic factor (GDNF), which is known to influence neuronal survival, differentiation and neurite morphogenesis. Enzyme-linked immuno-sorbent assays revealed that GDNF, covalently tethered onto polycaprolactone electrospun nanofibrous scaffolds, remained present on the scaffold surface for 120 days, with no evidence of protein leaching or degradation. The tethered GDNF protein remained functional and capable of activating downstream signalling cascades, as revealed by its capacity to phosphorylate intracellular Erk in a neural cell line. Furthermore, immobilisation of GDNF protein promoted cell survival and differentiation in culture at both 3 and 7 days. This study provides important evidence of the stability and functionality kinetics of tethered molecules.

Clinically, physical, electrical or ultrasound stimulation is used to promote cell and tissue self-repairing. Though research on ultrasound stimulation mostly uses high frequency ultrasound stimulation, in our project, we use low frequency ultrasound stimulation of different intensities to treat AML-12 hepatocytes. The cells growth condition and albumin secretion was tested. The results show no difference related to ultrasound intensity for the growth condition and albumin secretion of AML-12, but ultrasound did not cause apoptosis.

To investigate the hemodynamic performance of overlapping bare-metal stents treatment of thoracic aortic aneurysms (TAA), three simplified geometric models, named, no stent, with one single stent and two overlapped stents were studied and compared in terms of velocity profiles and wall shear stress (WSS) distributions by means of computational fluid dynamics (CFD). The results showed that overlapping bare-metal stents intervention significantly decreased the WSS and the blood flow velocity in the aneurysm sac, meanwhile the vortex in the sac became weaker and weaker. The results indicated that overlapping stents intervention may effectively isolate the thoracic aortic aneurysm, protecting it from rupture. In conclusion, overlapping bare-metal stents may serve a similar purpose to that of the multilayer flow modulator (MFM) manufactured by Cardiatis SA (Isnes, Belgium).

This work aims at developing a system dynamic model that can simulate various hemodynamic and wave characteristics associated with the counter-pulsation circulation support. A novel hybrid circulation model consisting of a one-dimensional (1-D) flow model and a lumped parameter Windkessel model was constructed. High-resolution Roe-splitting was developed for wave capturing and Runge-Kutta method was used for time-stepping this coupled hybrid circulation system. Wave propagation phenomenon in the arteries was successfully simulated. By adjusting the time-varying elastance of the ventricles, the healthy and failed heart conditions can be simulated. Failing heart supported by intra-aortic balloon pump (IABP) was simulated. These simulation results indicate that for 40 ml IABP support, cardiac output was elevated 4.1%. During systolic unloading, IABP deflation generated a backward decompression wave, with a “sucking” effect toward the aortic root, resulting in a reduced left ventricular afterload. During diastolic augmentation, IABP inflation generated a backward compression wave, with a “pushing” effect toward the aortic root to help coronary diastolic perfusion. Wave patterns of counterpulsation can be investigated using wave intensity analysis, which is able to quantitatively assess diastolic augmentation and systolic unloading of IABP counterpulsation based on a strict energy transport theory of wavelet.

To test the hypothesis that the venous graft when implanted in an arterial bypass might endure a fast infiltra-tion/accumulation of low-density lipoproteins (LDLs) within the vessel and hence the accelerated atherogenesis. we meas-ured measured DiI-LDLs uptake by both arteries and veins under arterial condition. The experimental results showed that that the amount of DiI-LDLs uptake by the venous wall was much higher compared with arterial wall, which was con-sistent with our hypothesis.

In order to verify whether differentiation of human stem cells toward bone tissue is promoted by higher acoustic vibration (≥90 Hz), human mesenchymal stromal cells (hMSCs) were mechanically stimulated with vibration (400 and 800 Hz, 0.3 g acceleration) for 30 min every 24 h for 7 or 14 days in vitro. Cells were seeded in osteogenic medium, which enhanced differentiation towards bone tissue. The osteogenic differentiation of hMSCs under the vibrated and non-vibrated conditions was assessed by examining mRNA expression of various osteoblast-associated markers (ALP, Runx2, osterix (Osx), collagen type I (Col I) and osteopontin (OPN)), and matrix mineralization. Our results indicated that acoustic vibration at frequency 800 Hz was more favorable for hMSCs osteogenic differentiation: the gene expression involved in osteogenic differentiation was significantly increased after 7 and 14 days, and deposition of calcium was almost 1.5-fold. Further studies are necessary to verify the long-term viability and commitment to osteogenic differentiation of hMSCs in vitro and in vivo, and select the optimum sensitive acoustic frequency, with the purpose of determining whether acoustic vibration could become a novel means to treat osteoporosis.

The epithelial to mesenchymal transition (EMT) involves several physiological and pathological phenomena and endows cells with invasive and migratory properties. We use the microplate measurement system (MMS) to measure cells stiffness. The EMT cells will have higher stiffness. However, treating inhibitor Cyto-D and ML-7 will lower cells’ stiffness. Based on this, we can use mechanical properties, to be a principle of the EMT process.

Vascular pulsatile tinnitus is a common and serious symptom, but no clear biomechanism. According to clinical radiographic reports, coloboma of cortical plate attaching sigmoid sinus occurs widely among patients, and most of them can be cured through cortical plate reconstruction surgery. Therefore cortical plate coloboma is a high-possibility etiology causing vascular pulsatile tinnitus. To study the mechanical relationship between cortical plate coloboma and vascular pulsatile tinnitus, finite element models of sigmoid sinus flow field and cortical plate were developed based on CT images. The generation and propagation of tinnitus noise were simulated separately. The model with and without cortical plate were analyzed to make comparison. The evaluation result provided a mechanical conclusion that coloboma of cortical plate attaching sigmoid sinus would remarkably amplify the noise generated in sigmoid sinus, therefore directly leading to audible perception. The conclusion also positively supported the cortical plate reconstruction surgery to cure vascular pulsatile tinnitus.

Pilots have been often sustained ejection-induced spine trauma and investigation of dynamic response of spine benefit for the insight of injury mechanism and design of protective device under ejection condition. This study developed a nonlinear finite element (FE) model of the thoracolumbar spine and a multi-body dynamic model of dummy respectively. The kinetic data of multi-body model and stress information of FE model have been analyzed. It can be found that ejection impact induces obvious axial compression and anterior flexion of the spine, which may contribute to the incidence of spinal injury. The high stress was located in T1 and L1 which has more risk of injury during impact loading. The combination of FE method and multi-body dynamic approach provides a convenient tool for studying occupants restrained by seat belts, such as drives, aviators, etc.

Idiopathic carpal tunnel syndrome (CTS) affects a significant portion of the population, although its exact etiology remains unknown. Based on dynamic ultrasonographic examination of the carpal tunnel inlet, in thumb and index finger (IF) flexion, we observed that the tendon(s) moves in the volar-ulnar direction, displacing the median nerve in the same direction. In middle finger (MF) flexion, however, the tendon moves dorsa-radially, leading to the volar-ulnar movement of the nerve. Median nerve and tendon displacements increased from thumb, IF and MF flexion. These general motion patterns were applied to a patient-specific computer-generated model of the carpal tunnel to determine the associated pressures. Motions in which the tendons move volarly, as in IF and thumb flexion, elicit greater nerve contact and von Mises stresses than those in which the tendons move in a dorsal-ulnar direction, as in MF flexion. Nerve displacement was also not directly correlated with nerve stress. The utilization of finite element modeling allows direct quantification of stresses within the tunnel without any invasive procedures, and may provide insight into the changing intra-carpal mechanics as CTS develops, which may lead to more effective CTS treatment.

Radio-frequency ablation (RFA) heat treatment is a popular “minimally invasive” treatment method for both primary and metastatic liver tumors, and the heat treatment is studied by numerical calculation. Most of numerical modeling in radio-frequency ablation use commercial finite element methods package. The present paper describes the model used finite difference methods to simulate RFA with internally-cooled electrode, and large blood vessels cooling simultaneously. A finite difference model is used to solve all partial differential equations (PDEs) for a simple three dimensional (3-D) cubic geometry model. Maximum tissue temperature is used as a critical index for reaching thermal lesion during RFA. Cylindrical RF cool-tip electrode is internally cooled at constant water temperature. The use of series and parallel thermal resistances of composite materials are presented in the model. Results show consistency with experimental results.

The present computational model is aimed at predicting the temperature field in a region of the hepatic parenchyma with a cancer resulting from applied high-intensity focused ultrasounds (HIFU) for thermal ablation of the tumor in a patient-specific geometry. The three-dimensional (3D) acoustic–thermal–hydrodynamic coupling model computes the pressure, temperature, and blood velocity fields expressed by the nonlinear Westervelt equation with relaxation effects and bioheat equations in both the hepatic parenchyma and blood vessels (sink). The classical nonlinear Navier–Stokes equations related to mass and momentum conservation in large hepatic blood vessels are employed both for convective cooling and acoustic streaming. This 3D three-field coupling demonstrates that both convective cooling and acoustic streaming change the temperature considerably near large blood vessels. In addition, acoustic streaming cannot be neglected due to resulting velocity magnitude and blood redistribution between different branches. The results presented in the current work can be further used to construct a surgical planning platform.

Dental implantation has brought about not only the occlusive capability restoration for edentulous patients, but also provided a better choice for the tooth reconstruction. With the advancements of science and technology, a satisfactory success rate of the dental implantation was reported. However, the mechanical behavior of the dental implant is still not similar to a natural tooth with the periodontal ligament. The micro-motion mechanism is the main difference between the natural tooth and the dental implant. Therefore, the aim of this study was to develop a novel dental implant abutment with a micro-motion mechanism that imitates the biomechanical behavior of the periodontal ligament, with the goal of not only maintaining the primal success rate but also increasing the long-term survival rate of dental implants. Firstly, computer-aided design software was used to design a novel dental implant abutment with an internal resilient component with a micro-motion capability. The feasibility of the novel system was investigated via finite element analysis. Then, a prototype of the novel dental implant abutment was fabricated, and the mechanical behavior was evaluated. The compression test of the novel dental implant was performed to prove micro-motion function. Moreover, the fatigue test of the novel dental implant was executed on the basis of the ISO 14801 standard. The results of the finite element analysis and the compression test confirmed that the novel dental implant abutment possessed the anticipated micro-motion capability. The nonlinear force-displacement behavior apparent in this micro-motion mechanism imitated the movement of a human tooth. Furthermore, the novel dental implant accomplished the fatigue test successfully at 5,000,000 cycles with frequencies of 5 Hz. The maximum endured load of the fatigue resistance of the novel dental implant is 160 N according to the ISO 14801 standard.

The particulate matter on the floor is at first detached and resuspended from the floor and then redistributed by human activities (i.e. walking). The objective of this paper is to investigate experimentally particle resuspension and redistribution due to human foot motion. The flow visualization with actual foot tapping was also carried out to demonstrate the particle resuspension. The experiments were carried out by flow visualization and Particle Image Velocimetry (PIV) measurements. To define the measurements better, the foot was modeled either as a disk, an elongated plate or a slipper-wearing foot model, that moved normal to the ground. The results indicate that particles can be resuspended with the walking process by aerodynamic mechanism. The particles resuspension is caused by wall jet between the foot and floor, and the particles redistribution takes place by the vortex dynamics.

The Center of pressure (COP) measurement is an important tool used for quantifying the dynamic properties of human’s balance and can be used to assess the risk of falling among elderly people. This paper presents a novel COP measurement device, based on three pressure sensors and double layer-designed insoles. Via a data acquisition (DAQ) device, the collected data can be remotely transmitted to wireless receiver Bluetooth. The aim of this study is to reduce hardware costs by using low-cost materials to gain the same results as the commercial portable COP measurement products. Experimental results show that the correlation coefficient of two systems is r=0.871±0.03 for the medio-lateral direction, and r=0.835±0.078 for the anterior-posterior direction. The results suggest that the design study delivers stable and reasonable results and that a low-cost pressure system is feasible.

Gait analysis has been widely used in the diagnosis of locomotors pathology and the assessment of treatment. But study of gait on Piriformis syndrome (PS) remain unclear. 3-D motion analysis was used to measure the kinematic and kinetic together with temporal-spatial parameters data of patients with PS and normal controls during walking. Patients with PS show significant increase gait speed and cadence, and peak extensor moments with increased flexion, abduction and internal rotation at the hip during the whole gait cycle. There were no significant differences in all the variables between the affected and unaffected limb in the patient group. These results may provide some advice on future work of rehabilitation and research of PS patients.

The nematode

Caenorhabditis (C.) elegans

has been widely used as a model animal for fundamental biological research. In order to investigate the effect of exercise on degenerative behaviors of

C. elegans

, such as physiological (lifespan, progeny) and biomechanical (propulsion, total power and swimming gait) properties, we developed a flow visualization technique to characterize the motility of

C. elegans

.

Quantifying the motility of micro-organisms is always essential in understanding their biomechanical properties. Up to date, however, the direct measurement of the motility of

C. elegans

remains a big challenge due to lack of proper tools. Therefore, a simple image-based algorithm using a micro-particle image velocimetry (

μ

PIV) for deriving the kinetic power and propulsive force of the nematode

C. elegans

was developed in this study. For the measurement, each worm was confined in a 0.5

μ

L droplet which was sandwiched between two glass slides separated by two tapes. The motility of the confined worm was derived from the fluid motion according to the law of conservation of energy. The experimental result showed that our measured values appear to be in good agreements with the prior data. The image-based algorithm was proven to be a simple and automated measure for characterizing the dynamic motility of micro-swimmers. The study will eventually provide valuable information for treating and preventing degenerative diseases in higher animals.

During bone fracture healing, both angiogenesis and mechanical fixation are of great significance. This study aims to obtain 3D structure of vascular network surrounding the fracture site at different healing times using vascular perfusion and micro-CT imaging technology, and to explore the influence of mechanical fixation on 3D structure of vascular network at the fracture site. To achieve the goal, transverse fracture surgery were performed on thirty six SD rats’ right tibias. Half of them (SF) received stable fixation with a newly custom-designed circular external fixator and the rest (NF) didn’t received any fixation devices. The imaging results indicated that compared with NF samples, SF samples contained more vascular distribution along the tibia, inferring a much more similar 3D structure to the CON samples (all of the thirty six rats’ left posterior limbs were taken as control group), which tends to be beneficial to the vascular reconstruction at the fracture site.

Degenerative disc disease is one of the most common diseases resulting from inflammation and instability around the affected spinal disc. Total disc replacement (TDR) is one non-fusion technique emerging as potential solutions to this condition, which can be used to restore normal motion in the spine. Although the first generation TDR devices have reasonable clinical results, similar to fusion, but several concerns in the current technologies are the inability to provide adequate shock absorption capability and time-dependent biomechanical behaviors. In order to improve this problem, second generation TDR devices incorporate more properties of a natural disc. Therefore, the objective of this study is to develop a novel biomimetic TDR device, and to demonstrate scientifically whether its biomechanical behavior is similar to that of a natural disc. Three-dimensional finite element (FE) models of a lumbar spinal motion segment (L4-5) with implants including Charité, Maverick, and the hydrogel-based TDR devices were created. With these models, the three different TDR design concepts were compared with respect to their ability to mimic the behavior of a natural disc. The analysis results indicate that the hydrogel-based TDR device could maintain the ROM well compared to that of a natural disc. However, the model with the novel TDR device predicted a marked increase of facet joint forces due to the relatively low rotational stiffness, especially in lateral bending. Although many steps are still necessary before the hydrogel-based TDR device can be used in clinical surgery to relieve back and leg pain associated with DDD. The results provide further insight into the biomechanical behavior of this novel TDR device under comparable physiologic loading conditions, and indicate that it is a feasible and promising approach.

Soccer is one of the world’s most popular sports, in which players must sometimes use their unprotected heads in offense or defense. In recent years, controversy surrounding the long-term effects of repeated impacts from heading has raised attention from the medical community. Previous works using numerical simulation studied the responses of the human brain during American football-related concussion. This study aims to estimate the response of the human brain to soccer-heading impacts using the finite element method. A validated full-body human model was used to analyze the impact simulation. The soccer ball flew with a translational velocity of 6 m/s or a rotational velocity of 30 rad/s. Players usually hit the ball with their foreheads or tops of heads while heading. Acceleration, Head Injury Criterion, principal strain, principal strain rate and shear stress of white matters in the brain are compared among different headings. The head motion during heading increases the acceleration of the brain during heading. The back spin of the ball increases its shear stress and strain rate during heading. When a moving player heads a ball with back spinning, the risk of mild traumatic brain injury may be high. This study shows that high strain and strain rate concentrate around the corpus callosum and shift from the impact site to the opposite direction. This observation is similar to those gathered from previous studies that simulated concussions sustained during American football.

Learning performance can be improved by practicing tasks with higher difficulty, a phenomenon known as the contextual interference (CI) effect. In this study, we investigated changes in the baseline functional connectivity of the brain when the participants practiced the serial reaction-time (SRT) task arranged respectively in an interleaved (higher CI) and a repetitive (lower CI) order. The resting-state functional magnetic resonance imaging (fMRI) data was analyzed using the group independent component analysis (ICA) to identify functionally homogeneous brain regions. These regions served as the nodes of the resting-state networks (RSNs) of the brain. Seven RSNs crucial for motor learning were identified, including the basal ganglia, sensorimotor, visual, auditory, visual, attentional, and the default-mode networks. We further found that the interleaved practice led to stronger functional connectivity than the repetitive practice within the default-mode network, particularly between the posterior cingulate and visual cortices, which are key regions for memory and visuospatial integration respectively. Our findings indicate that practice with higher difficulty enhances the baseline connectivity within the functional circuits of the brain, providing a neural basis for the benefits of higher CI practice on motor learning.

The malignancy of breast tumors are evaluated via ultrasound images on clinical examination. As a second viewer, a computer-aided diagnosis (CAD) system was developed to classify the breast tumors using texture features to avoid misclassifying carcinomas. A total of 69 cases including 21 malignant and 48 benign masses were acquired. For intensity-invariant texture extraction, the ultrasound images were first transformed into ranklet images to reduce the effect of brightness variability. From the ranklet images, tumor texture and speckle texture were extracted and compared to those from the original ultrasound images for tumor diagnosis. In the trade-offs between sensitivity and specificity, the ranklet-based tumor texture and speckle texture were all significantly better than those of the original US images (Az: 0.83 vs. 0.58, p-value=0.0009 and Az=0.80 vs. 0.56, p-value=0.02). The proposed CAD system using textures from intensity transformed sonographic images is robust to various gray-scale distributions and is more suitable in clinical use.

This paper proposes a non-rigid, symmetric and diffeomorphic algorithm for the registration of MR images. A log-Euclidean framework was used to model diffeomorphisms. Multiple features were used to enhance the speed of the proposed algorithm, including compactly supported Wendland’s basis functions as models of velocity fields, a greedy optimization strategy, and a coarse-to-fine hierarchical framework. Symmetry was ensured through the invertibility of diffeomorphisms and the symmetry of the objective function and optimization algorithm. The proposed algorithm was evaluated using the results of 1560 pairwise registrations of 40 T1-weighted MRIs in the LPBA40 dataset. Our results demonstrated that the proposed algorithm is diffeomorphic with sub-voxel accuracy in terms of symmetry. The proposed algorithm outperforms 14 other registration algorithms in terms of speed (compared with diffeomorphic algorithms) and accuracy.

This paper presents the Support System for auto-Pathological Diagnosis (P-SSD) to support pathologists and researchers of auto-pathological diagnosis. P-SSD has two main contributions. First, P-SSD detects cancer area with machine learning methods, and then shows cancer areas to pathologists. The pathologists can make diagnosis with the detected result, which reduce the burden on pathologists. Second, P-SSD is an open software platform for pathological image too. The platform offers some basic functionalities to load and display pathological images, and implement the image-processing methods though plugins. It helps researchers to apply feature calculation and machine leaning techniques to the pathological images effortlessly. In conclusion, P-SSD is the software with potential applications in both of pathological diagnosis and research.

Transcranial Doppler (TCD) ultrasound is commonly used in some departments to detect blood flow and emboli in the cerebral artery at the forefront of medical technology. Conventional TCD systems expose more and more disadvantages such as inadequate depth information, low sensitivity and poor accuracy in clinical diagnosis. In this study, a full digital design of TCD ultrasound system is introduced, in which raw radiofrequency (RF) is directly converted to digital data with an A/D converter. All signal processors such as digital I/Q demodulator can be achieved by utilizing digital signal processing (DSP) techniques. This design can solve the problems above. In particular, it offers a full-depth intracranial examination, which can be used to locate transcranial windows conveniently so as to make TCD analysis much easier even for an inexperienced person. Furthermore, coded excitation is allowed. In our experimental system, RF signals are collected

in vitro

from a flow phantom using a TCD system, which alternately transmitted 8 wavelengths normal pulse and 4 wavelengths pulse coded by 7-chip Barker code. The

in vitro

results are promising. Qualitatively the blood flow is easier to track using the pulse compressed signal. It is both feasible and beneficial to implement the full digital design in a TCD system.

The purpose of this study is to use sodium magnetic resonance imaging (sodium MRI) to observe the variations in sodium signal intensity in mice brains after ischemic stroke, and to estimate the tissue sodium concentration of the ischemia area in mice brain. Experiments were performed using a 7T MRI system. Before the MRI scan (48 hours), the mice underwent middle cerebral artery occlusion (MCAO) to induce focal brain ischemia. The average signal intensity in the sodium images of mice brains showed a 2.2-fold increase. The average estimated values of the ischemia area and contralateral area in the mice brains were 106.5 mM and 49.9 mM, respectively. This study demonstrates the feasibility of sodium MRI in mice brain of ischemic stroke at 7T MRI. The signal intensity of sodium on the mice brain shows a significant increase in the ischemia area compared to the contralateral brain hemisphere. The estimated values of the sodium concentration exhibited a significant correlation with the biochemical values of the sodium concentrations.

The development of an average glandular dose (AGD) assessment method of the resolution testing phantom is useful in mammographic study. The purpose of this study was the evaluation of image quality and AGD using the resolution testing phantom in mammography. The equivalent thickness of the standard breast phantom with percentage glandular content (PGC) of 50% that would require the same mAs as the resolution testing phantom was calculated. In this study, 2-6 cm resolution testing phantoms were exposed at target/ filter/kV combinations of Mo/Mo/27 and 28 kVp. The AGD and spatial resolution of these images were analyzed. Results from this study showed that the equivalent thickness of standard breast linearly increases with increasing thickness of resolution testing phantom. The measured spatial resolutions for different tube voltages were comparable (6-8 lp/mm). The calculated AGDs for the tube voltage of 27 kVp were slightly higher than those of 28 kVp. In conclusion, the equivalent thickness of standard breast phantom (PGC=50%) producing the same exposure factors as resolution testing phantom was developed. As a consequence, both image quality and AGD information can be acquired during the spatial resolution testing in mammography.

In this paper, preliminary simulated reconstruction results are presented to investigate the effects of geometrical mismatch between the physical and computational models on the reconstructed images. Two types of mismatch are discussed.

Stereo tracking systems are used in surgical navigation to measure 3D positions of surgical instruments and patients, including invisible light based tracking systems and image based tracking systems. Optical tracking systems use reflective balls or flat chessboards as markers which can not be used in limited space. This paper introduces a new 3D spatial position measurement system using 3D image markers based on integral photography. This 3D image marker has spatial information encoded into a 2D image. Therefore, it has compact size while providing spatial position measurement. We design 3D image markers for a special probe and display them in 3D space using integral photography. Furthermore, we fulfill the stereo camera calibration, keypoints extraction and 3D position calculation. Experiments were performed to evaluate the accuracy of the system and the application is clarified to express the practicability of integral photography based 3D image markers.

Ischemic stroke is a high prevailing and disease in industrialized countries. A valid animal model is essential to develop an extensive research. Among various models, middle cerebral artery occlusion (MCAO) is one of the common used ischemic stroke animal models. In this study, we evaluate the absorption coefficient, reduced scattering coefficient and hemodynamic responses using near infrared spectroscopy (NIRS). The correlation between NIRS signals and the brain infarction volume was measured from histochemical stain. Through the well correlation about reduced scattering coefficient, NIRS can be an effective tool to evaluate ischemic stroke.

The majority of studies investigating correlations between personality and neuroscience have used the Big-Five personality scales developed in Europe and North America. This is the first study to address correlations between Chinese personality traits and cortical activation.

In this study, we used the Chinese Personality Adjective Rating Scale to analyze the personalities of 23 respondents. We also used functional magnetic resonance imaging to explore the correlations between Chinese personality traits and cortical activation. The results of this study indicated that Optimism/ Pessimism, Extraversion/Introversion, and Industriousness/ Unindustriousness from the Chinese Personality Adjective Scale were correlated with Neuroticism, Extraversion, and Conscientiousness from the Big Five personality traits. The activation positions were consistent with those identified in earlier studies. Additionally, this study indicated that the clearest position of activation for the dimension of competence vs. impotence was the supplementary motor area. The temporal gyrus and hippocampus were negatively correlated with moral character. The activation of the limbic system was positively correlated with large-mindedness vs. small-mindedness, and the thalamus, temporal lobe, and parietal lobe were positively correlated with flexibility vs. rigidity.

This is the first study to address correlations between Chinese personality traits and cortical activation. The results of this study can serve as an essential reference for research on Chinese personality traits and neuroscience.

Shearwave Dispersion Ultrasound Vibrometry (SDUV), a method could quantify both tissue elasticity and viscosity has been introduced recently. Vibration extraction is an important step in SDUV. Two vibration extraction algorithms, the quadrature demodulation method (QDM) and the cross-spectrum method (CSM) are usually used in SDUV. However, the extraction quality of QDM and CSM are under appropriate comparison. This study aims at comparing the extraction quality of QDM and CSM based on a parameterized model for various signal-to-noise ratio of ultrasound echoes

(SNR

U

)

Results showed that when

SNR

U

≥

35

dB

, the standard deviations of the estimated vibration phase using the vibration extracted by the two methods are close, which has no significant differences on the calculation result of the shear wave speed. The computation efficiency of CSM is lower than that of QDM. As a conclusion, when

SNR

U

<

35

dB

, the tissue vibration should be extracted by CSM to suppress the estimation error of vibration phase. However, when

SNR

U

≥

35

dB

, the tissue vibration should be extracted by QDM to reduce the processing time. The findings in this study may provider some strategy in SDUV, which can optimize the examination protocol and make it more efficient.

Sleep diseases, such as insomnia and obstructive sleep apnea, seriously affect patients’ quality of life. For diagnosis, polysomnographic (PSG) recordings are most usually taken to evaluate the sleep quality and efficiency. However, the large amount of wires connections for conventional PSG often cause sleep interference and not self-applicable. In this study, a complexity-measure-based method for evaluating the sleep quality was proposed. We utilize multiscale entropy (MSE) to analyze the 32 all-night sleep polysomnographic (PSG) recordings from 32 adults. The range of the subjects’ sleep efficiency was from 56% to 97%. Half of the subjects’ sleep efficiencies were equal or higher than to 85% (good sleep) and the other half were lower than 85% (poor sleep). The result shows that the averaged MSE values of poor sleep efficiency group are higher than good sleep efficiency group in each scale factor. This means that the complexity of sleep EEG of poor sleep efficiency group is higher than good sleep efficiency group. This finding may be used to quickly distinguish the subject’ sleep efficiency is good or poor.

The waxing-and-waning high-voltage spindles (HVSs) are the electroencephalographic hallmarks of the abnormalities in the synchronization of oscillatory activities in cortical-basal ganglia networks. The HVSs were observed during waking immobility on lesioned Sprague-Dawley rats by unilateral injection of 6-hydroxydopamine (6-OHDA). The local field potentials (LFPs) collected from the lesioned and control rats were analyzed with continuous wavelet transform using a tunable complex Morlet wavelet function identified with a careful choice of design parameters for the efficient detection of HVSs. In this study, an online detection algorithm optimized with suitable wavelet parameters using a window size of 500 and a constant decision threshold, is verified to detect the HVSs lasting 1.15-3.49 seconds from seven lesioned rats with maximum precision, sensitivity and specificity. These results provide further motivation for the real-time implementation of the automatic HVS detection systems with improved performance for pathophysiological and therapeutic applications to the thalamocortical network dysfunctions like Parkinson’s disease.

Sound signal can be decomposed to a slowly varying envelope cue and a rapidly varying fine structure cue. These cues can help people to sound perception, sound lateralization, speech recognition in noise, and so on. Cochlear implant can help people with hearing loss to hear the sound. However, there are still many restrictions with cochlear implant user and a gap between normal hearing and cochlear implant user. This study investigated the contribution of envelope and fine structure cues with different SNR and simulated cochlear implant in Taiwanese mandarin speech recognition in noise. Ten normal hearing subjects participated in this experiment. Our result shows sentence recognition in noise almost depends on the envelope cues, but the fine structure cues still have limited contributions.

Electrical Impedance Tomography (EIT) is a non-invasive image reconstruction technique. Typically, an EIT scheme involves the solution to an inverse problem, which usually gives a poor resolution, due to linearization and ill-posedness of the problem. An alternative approach based on Artificial Neural Networks (ANN) has been used as a replacement of the inverse problem, giving correct results without linearizing the problem. However, training an ANN may be time consuming and usually requires a large amount of iterations before achieving a correct answer to the input stimulation. Several studies focused on training ANNs, and Evolutionary Algorithms (EA) gives a faster global convergence. In this paper, a novel approach based on Artificial Neural Networks and Particle Swarm Optimization (PSO) is proposed to improve the training process. A training method based on PSO algorithm achieves a faster global convergence.

This study utilized movement-related sensorimotor Mu rhythm to probe EEG abnormalities in leukoaraiosis patients when they were performing self-paced finger movement task. The differences in EEG Mu rhythms between patients and normal subjects were studied and compared. Leukoaraiosis is a descriptive term used to describe neuroimaging findings of diffuse hemispheric white matter abnormalities, mainly characterized by loss of myelin and/or ischemic injury. The leukoaraiosis has been suggested a major risk factor and prognostic factor for stroke. Since EEG signals are weak (

μ

v) and stochastic, the use of traditional digital filter may be unable to well extract the stochastic sensorimotor rhythms which could result in the pitfall of underestimating subject’s responses. Accordingly, a novel tool, multivariate empirical mode decomposition (MEMD), was adopted in this study to exact the sensorimotor Mu rhythm in human brain. Our results found the beta event-related synchronization (ERS) of EEG Mu rhythm in Leukoaraiosis patients are significantly lower than those in normal controls using conventional event-related synchronization (conventional beta ERS) (0.44(0.2 uv v.s. 0.84(0.42) (student’s t-test, p<0.01). Further analyzing the single-trial beta ERS using MEMD approach, the single-trial beta ERS in Leukoaraiosis patients and normal controls were 2.02(1.68 uv and 1.68(0.73 uv (student’s t-test, p<0.05). It can be observed that the standard variation of single-trial beta ERS in Leukoaraiosis patients is larger than that that in normal controls (1.68 uv. v.s. 0.73 uv). The large signal variation in beta ERS could result in the suppression of conventional ERS values in Leukoaraiosis patients.

The Immunochromatography test strip (ICTS) is a one step and the commonest commercial point-of-care diagnostic format. Their advantages of convenient and fast testing enable the rapid decisions on diseases. However, the fundamental limitation of quantitative and sensitive analysis severely hampers their application in the field of early detection. Herein, we overcame these limitations by integrating of quantum dots with distinct optical and electronic properties, which were served as the signal reporters for ICTS. Human chorionic gonadotropin (HCG), which has been recognized as a clinic marker of pregnancy, was used as a model analyte to demonstrate the performance of the QDs-based ICTS platform. Under optimized conditions, the detection limit was about 0.24 IU/L. Meanwhile, the concentrations of HCG could be determined within 20 min with high specificity, using only 40

μ

L of sample. Our data suggests that the QDs-based ICTS platform is a rapid, low-cost, highly sensitive and specific test platform for quantitative point-of-care diagnostics, which holds promise to become part of routine medical testing for other protein markers detections.

We investigated the effect of transforming growth factor-beta1 (TGF-

β

1) on cell micromotion and wound healing migration of breast adenocarcinoma cells, MDA-MB- 231. Central to this work was the use of electric cell-substrate impedance sensing (ECIS), a cell-based biosensor that monitors motility and other morphology changes of cells adherent on small gold electrodes. To detect the alternation of cell micromotion in response to 10 ng/ml of TGF-

β

1 challenge, timeseries impedance fluctuations of cell-covered electrodes were monitored and the values of variance, power slope, and Hurst coefficient were calculated to verify the difference. These measures describe the motile and persistent behavior of these cells in culture. Furthermore, ECIS wounding assay was used to wound and monitor the healing process of TGF-

β

1 treated cell layers. Our data indicated that TGF-

β

1 treated MDA-MB- 231 cells, in comparison to control cells, demonstrated higher fluctuation amplitude and unreduced long-term correlation for about 20 hours long. In addition, the wound healing rate of MDA-MB-231 cells significantly increased after cells were treated with 10 ng/ml of TGF-

β

1 though the effect decreased along with time. The results suggest that treatment of MDAMB- 231 cells with TGF-

β

1 facilitates their scattering behavior.

In this paper, we have demonstrated the performance improvement of the air-borne Capacitive Micromachined Ultrasonic Transducers (CMUT) in transmit mode using the Helmholtz resonance principles. The natural frequency of the resonance cavity, and the Helmholtz resonance frequency of the aperture which is formed in the center of membrane, were matched for resonance during the design. In order to verify the theoretical concept, Finite Element Analysis (FEA) simulation was performed using COMSOL software. Through the simulation comparison with the traditional CMUT, the proposed CMUT demonstrates the feasibility to improve the output acoustic pressure and SPL of the air-borne CMUT in transmit mode by combining the mechanical resonance theory with Helmholtz resonance principle.

Normally, bedridden patients need nurses to help moving their body or changing lying positions. However, to patients, changing lying positions by others may cause two problems: One is the timing and frequency of movement may not be adequate and the other is the cozy position of the movement may not be perfect for patients. Therefore, in this study, we tried to build up a handy system which can help bedridden patients to control hospital beds in several lying positions that match their preferences closely by only moving their eyes. In the results, we have already built up an eyecontrolled equipment which allowed user to control hospital beds by themselves. This equipment had advantages of light and handy. Besides, we also constructed a model of our homemade hospital bed with six specific bed boards. This new type may help users to change their lying positions in left right tilt. Although there still have some tests to be conducted, the system of using eye control on our new type of hospital bed is possible. In the future, we expect that this handy system can help bedridden patients to appropriately control hospital beds in several lying positions that match their preferences closely by only moving their eyes.

Stochastic resonance (SR) has been regarded as improving functions of sensory and motor in human via noise input, and increasing feedback of somatosensory may improve ability of posture control in upright standing. To date, regardless of previous literature has reported its efficacy of improving postural control, whether optimal noise can be used remains largely unknown. Present studies examined whether there was effect on postural control in upright standing using two types of interference waves: white noise (WN) with sinusoid signal and Gaussian noise (GN) with sinusoid signal. The finding suggests a promising setup for its application to increase postural control in upright standing. This study is aimed to examine the different effect on postural control in upright standing using two types of interference waves.

The purpose of this study is the investigation of compressed thickness of the fix and flexible compression paddles using a Bolus phantom in digital mammography. A 5-cm-tihck Bolus phantom and a 5-cm-tihck PMMA phantom were used for the assessments of compressed thickness. The compression forces of 0-200 N and 0-140 N were applied to the Bolus phantom and the PMMA phantom, respectively. Results from this study show that the displayed thickness of the PMMA phantom was greater than the displayed thickness of the Bolus phantom for the same compression force. The difference of displayed thickness was increased with increasing compression force and the maximum value was 0.4 cm. In conclusion, the Bolus phantom is suitable for the measurements of compressed thickness during mammographic compression procedure.

In the hospital the inpatients’ meal is not only for patient’s hungry, is also for the treatment assistant. The meal is designed and ordered by the nutritionists, which are basing on the physician’s advice. But in a hospital a nutritionist usually cares dozens patients, results in the heavy loading. In the meal order process, this involves departmental data transferring and manpower, and then needs lots of time. As a result, the first meal of the inpatient or the first modified meal would miss. For the purpose of providing the inpatients a in time nutritional care, so we proposed the inpatient meal booking system. Our system developed the electronic forms of meal booking based on the interactive Web technology. The physician’s advises are ordered via the web page, which are then directly transferred to the nutritionist. As a result, the nutritionist could get the inpatient’s data in time, and then assesses the nutritional requirements, issues the meal order.

This paper presents a wireless electrocardiogram (ECG) acquisition and monitoring system for healthcare application. This system consists of three parts, namely, an analog front end, a Reed-Solomon (RS) encoder, and a frequency-shift-keying (FSK) transmitter. The analog front-end circuit acquires and digitizes the ECG signal. The RS encoder encrypts the digitized data before being sent to the FSK transmitter. The encrypted data are then up-converted to radio frequency for wireless communication. The integrated system is implemented in TSMC 0.18

μ

m standard CMOS process and demonstrated on a printed circuit board to verify its capability to acquire the ECG signal from the human body.

An indentation technique is one of effective methods to determine the elastic modulus of materials using information about contact geometry, indenter shape and applied load. This paper presents a device and a method that allow us to estimate elastic modulus of soft materials through indentation by video tactile pneumatic sensor. The device is a sealed metal cylinder ending with a soft silicone shell of a semispherical shape with 5 mm radius. During penetration by the silicone tip into investigated material the measured parameters are contact radius and displacement of the central point of the shell.

The contact interaction between hollow elastic semisphere and a sample is modeled using finite element method. The axisymmetric contact problem was solved in geometrically nonlinear formulation, as the large strains were observed in the tests. The linear elastic model was used to describe mechanical properties of the sensor head and the sample. The Young’s modulus of the soft tissue was estimated based on the experimental results and numerical calculations.

A risk management report is an important part of the technical documentation of any medical device since it contains the risks and hazards linked to use and how the man-ufacturer handled them for the purposes of performance and safety. For devices sold in Europe, EN ISO 14971 provides methods and tools for manufacturers to analyze and manage the risks associated with their devices. This study analyzes a new dynamic spinal stabilization system based on ISO 14971 to optimize the performances and safety of the new design.

There are three common types of single tooth dental implant surgery. Bone level implant was first developed in 1965, and evolved to a simpler tissue level implant, which in turn, evolved into a one piece implant type. The structure of the one piece implant type combines the abutment and the fixture of an artificial tooth together. This study describes the current characteristics, surgical procedure, and issues of the one piece implant system, and explains how to resolve issues in the future.

A surgical tool with multiple degrees of freedom is designed, working as a laser ablation end-effector for minimally invasive surgery. The end-effector mainly consists of four springs which provide multiple degrees of freedom and four flexible shafts which contracts or extends four springs. The mechanical configuration of the designed end-effector is detailed presented and the mathematical model is formulated. The prototype of the end-effector is built and its motion performance is tested.

I Speech therapy is usually treated in the hospital by language therapist, but the home practice is also very important. The cooperation of parents and therapists would help children have a better effect. In this study, a home-practice platform is developed, which provides a collection of the correct pronunciations, practice methods and pronounce evaluations. As a result, the platform could enhance the progress of treatment and provide home exercises more resources for parents and children.

The narrow 3h therapeutic time window for recombinant tissue-type plasminogen activator (rt-PA) thrombolysis is a challenging limitation in acute ischemic stroke treatment. Intense research focus is being laid on developing novel therapeutic interventions for extending the thrombolysis time window using animal stroke models. However, these animal models are anatomically and physiologically different. Here, we assess the effective time window of rt-PA thrombolysis in the photothrombotic ischemic (PTI) stroke model using the electrocorticography (ECoG) system and histology study. Our results indicate that rt-PA provides effective thrombolysis when administered in the initial 1 to 3 hours post-ischemia, beyond which it does not facilitate recovery. This complements the FDA-approved rt-PA time window in humans. However, it is interesting to note that the trend of neural activity did not strictly correspond to infarct volume changes, indicating the importance of multimodal imaging for holistic assessment of therapeutic efficacy. Therefore, in the future, this ECoG setup will be integrated with the functional photoacoustic microscopy (fPAM) system to jointly evaluate neural activity and cerebral hemodynamics to probe neurovascular function changes effective with thrombolysis.

Block of the external urethral sphincter contractions by using high frequency electrical stimulation of the pudendal nerves is a potential method for inhibiting detrusor sphincter dyssynergia. Most researchers use high frequency electrical stimulation at frequencies between 2kHz to 20kHz, but the parameters and mechanism of this block are not well understood. This paper demonstrated the use of radio frequency electrical stimulation (500kHz) as a method to block the external urethral sphincter contractions and improved voiding efficiency by electrical stimulation of unilateral pudendal nerve efferent axons. The most efficient waveform for conduction was 500kHz (with 0.2 to 1mA) constant-current biphasic sinusoidal, voiding efficiency increased from 53 to 71-92%. These results raise the possibility that using radio frequency electrical stimulation to block external urethral sphincter contraction may provide a new approach for improving voiding in spinal cord injured patients.

In this study, a training system for an involuntary eccentric contraction of biceps brachii muscles was designed using a continuous passive movement and a commercial neuromuscular electrical stimulation devices. To investigate the effects of the involuntary eccentric contraction training by neuromuscular electrical stimulation on the enhancement of muscle strength, 7 healthy males participated, who were trained two times per week for 12 weeks. Each exercise session was performed for 30 minutes with no rest intervals. Isometric elbow flexion torque and biceps brachii muscle thickness were chosen as evaluation indices, and were measured at pre-/posttraining. After the 12-week training, the isometric elbow flexion torques significantly increased by approximately 23% compared to the initial performance (p < 0.01). In addition, the biceps brachii muscle thicknesses significantly increased by around 8% at rest and 16% at MVC (p < 0.01). The developed system and the technique show promising results, suggesting that it has the potential to be used to increase the muscle strength in patients with neuromuscular disease and to be implemented in design rehabilitative protocols.

Repetitive transcranial magnetic stimulation (rTMS), which is produced by strong non-static magnetic fields, is an non-invasive means to stimulate the cerebral cortex. The recent studies show that rTMS affects treatment parkinson’s dieses and improves motor symptoms in patients. However, the relationship between the clinical efficacy of rTMS and mechanism is still obscure. In this study we have investigated the effects of different stimulation frequencies and number of treatments on dopamine secretion and neural functions in SH-SY5Y cell cultures. A repetitive session of magnetic stimulation with no matter high or low frequency, intracellular ROS were decreased. In the same time, neurons after magnetic stimulation will release neurotransmitters. These results suggest a possible use of this particular physical stimulation to improve the functional capability of the cells to face oxidative stress. Based on our study we can more understand that the effect of repetitive transcranial magnetic stimulations (rTMS) on Parkinson’s disease.

The benefit of physical activity and exercise is protecting against the deterioration of brain tissue with age. Previous studies have suggested that exercises have positive effects on cognition, but gender difference is still unclear. Therefore, we focus on the gender difference in cognitive ability, which is an important component for daily living and quality of life, before and after exercise. However, executive function is a higher-order cognitive function for daily life, including planning, scheduling, inhibiting, and working memory. We measure the executive function by tasks of psychology, including Wisconsin Card Sorting Test (WCST), Tower of Hanoi and N-back test. Fifty-six participants were recruited with the mean age of twenty-three years. Participants were asked to complete the WCST, Tower of Hanoi and N-back test before and after the exercise which be executed at least thirty minutes. Finally, we calculated the scores of tasks before and after exercise. The results indicated that there was a significant positive exercise effect on the WCST, Tower of Hanoi and Nback test in executive function and also found the light gender differences in the three tasks of psychology.

Dopamine (DA) is a neurotransmitter involved in controlling of fine movement, which is deficient in Parkinson’s disease (PD). Measurement of DA is an urgent need concerning the development of PD therapy. We’ve developed a fastscan cyclic voltammetry (FSCV) for real time measurement of dopamine releasing in dopaminergic SH-SY5Y cells under tissue-specific optogenetic stimulation. With the novel cellular optical-induced DA-releasing model, the performance of FSCV will be validated under various stimulating parameters.

With the advancement of Brain-Computer Interface (BCI), human mind control devices is getting common in the medical field. In this paper, an attention level indicator was proposed in aid to monitor one’s attention level especially for Attention Deficient Disorder (ADD) patient. It was designed to activate the number of lightening LED lights by monitoring of the human attention level. NeuroSky Mindwave mobile headset was used to acquire the brain wave attention signals. A MATLAB programme was developed to perform signal processing, included data extraction, error detection and command setting. The extracted attention level parameters from NeuroSky ThinkGear software were set as an input command for activating the LED lights. These programs and commands were delivered to a microcontroller board, the Arduino UNO, to regulate the input and output systems. The LEDs attention level indicator can be used to monitor attention level from time to time. Finally, an experiment was carried out to investigate which type of activities would generate the highest undergraduate engineering students’ attention level. The results found out that female students obtained better focus on paying attention compared to male students. Also, female students shows result that able to focus better during visual based activity whereas male students were good at hands on based activity. However, in general, our group of samples of undergraduates students tend to pay higher attention on visual based activity than audio or hands on activities.

Study of cerebral cortical functions affected by ischemic stroke explicates post-stroke brain plasticity. We report an innovative combination of electrocorticography (ECoG) recordings and functional photoacoustic microscopy (fPAM) imaging to investigate cortical functions after photothrombotic ischemia (PTI) in rat brain, with electrical forepaw stimulation applied as treatment. The cortical functions were assessed over a chosen ischemic region via somatosensoryevoked potential (SSEP), resting-state ECoG signals and evoked hemodynamic response. Two-phased experimental protocols based on sensory stimulation treatment are proposed and performed in this study. In the phase 1, the treatment is applied to the left forepaw, contralateral to the ischemic hemisphere, with 2 mA pulses initiated 0, 1, or 2 hours postischemia to determine optimal onset timing. After determining the optimal time window, in the phase 2, the treatment was delivered unilaterally or bilaterally using 2 or 4 mA pulses for validating if bilateral peripheral electrical stimulation with different current intensities could improve cerebral perfusion and restore cortical neurovascular response. Overall, the results demonstrated that our treatment administered bilaterally at 2 mA within 2 hours of ischemia can promote neuroprotection significantly via reversed cortical functions, suggesting effective recovery.

Cortical Theta burst stimulation (TBS) may modulate dopamine-dependent corticostriatal plasticity via long-term potentiation / depression (LTP/LTD) -like mechanism. This gives TBS a therapeutic potential for Parkinson,’s disease (PD) and other neural disorder. To unravel the mechanism beneath TBS-induced neuroplasticity, a novel optogenetic simulating method will be applied. CaMKII promoter-driven channelrhodopsin-2 (ChR2) will be delivered into glutamatergic pyramidal neuron in motor cortex by lentivirus. Under emitting of precisely controlled blue laser guided by fiber optics, the excitatory circuit in layer V will be elicited with TBS paradigm. Cortical excitabilities were examined by measuring optogenetic simulation-evoked potential and motor-evoked potential (MEP). In summary, we proposed a novel optical-TBS rodent model, which revealed the function role of glutamatergic circuit in motor plasticity.

In modern society, people are often suffered the nervous tension for a long time, and results in inevitably internal injury of bodily functions. The periodic and comprehensive medical examinations are necessary, makes the chemistry analyzer to play an important role. Although the chemistry analyzer is operating automatically, different manufacturer defines distinctive specifications. That causes the interoperability problems in the chemistry analyzers, and the analyzed results could not share and integrating. Therefore, this study proposed to solve the problem, which was basing on the international standard protocols of ISO/IEEE 11073 and Health Level Seven (HL7) to develop a software application. The developed application could control the different brands of chemistry analyzers according to the ISO/IEEE 11073 standards. The data will be further compiled into HL7 format and save as an XML (eXtensible Markup Language) text file. Finally, the data are uploaded to the current hospital information systems. In order to achieve an interoperability platform that supports a variety of instruments at the same time. Not only enable the messages’ exchange in the healthcare systems, but also have high degree of sharing between the hospitals.

Prostate cancer (PCa) is the most common cancer form for men in Europe. A sensor system combining Raman spectroscopy and stiffness sensing with a resonance sensor has recently been developed by us for prostate cancer detection. In this study the sensor system has been used for measurements on two slices of fresh human prostate tissue. The stiffness sensor could detect locations slices with significantly different stiffness contrasts (p < 0.05). Raman spectroscopic measurements could be performed with the dual-modality probe for tissue classification. The findings are important for the continued development of a combination probe for prostate cancer detection.

”IFMBE Proceedings Vol. 47: ”1st Global Conference on Biomedical Engineering & 9th Asian-Pacific Conference on Medical and Biological Engineering” missed the contribution ”Prostate cancer detection using a combination of Raman spectroscopy and stiffness sensing” written by Olof Lindahl for technical reasons. The editors apologize for the mistake.