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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (SpO2) 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (0.5×106 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 2nd 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 2nd 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 cm2, 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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 (R2) was 90.1% which satisfied the adjustment of experimental data in the model. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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). [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]