Paper Title, Authors, Abstract (Issue 1, Volume 3, 2009)

Pages

A New Approach for Water Purification from Microbial Pollution
E. Moosavi, V. Martirosyan, S. Ayrapetyan

Abstract: The fact that low concentrations of CO2 have an activation effect on functional activity of microbes allows us to suggest that CO2 could elevate the toxic effect of H2O2 on cells. To check this hypothesis the dependency of the toxic effect of H2O2 on wild type of Escherichia coli K-12 on soluble concentration of CO2 in culture media was studied. The obtained data show that culture media enriched with CO2 leads to the increase of toxic effect of H2O2 on microbes at both cases when pH is constant and when it changes.
 

Can Functional Electrical Stimulation for Pressure Ulcer Prevention reduce efficiently the Incidence of Deep-Tissue Injury?
Dohyung Lim, Keyoung Jin Chun

Abstract: In the United States, 1.4 million people who rely on wheelchairs for mobility develop serious pressure ulcer (PU) at pressure areas such as ischium and sacrum due to prolonged sitting. Recently, functional electrical stimulation (FES) has been proposed as a means to prevent development of PU through the redistribution and the reduction of the internal stresses within the deep tissue of the buttock, which were achieved by the increase of the muscle thickness, particular in the gluteus maximus. However, rare information about how much reduction of the incidence of deep-tissue injury in the FES application for PU prevention are positively induced through the internal stress relief resulting from the alteration of the muscle thickness achieved by the FES is currently available. The objective of the current study was therefore to identify if the FES application may efficiently reduce the incidence of deep-tissue injury, by evaluating a degree of the internal stress relief through the alteration of the gluteus maximus muscle thickness using Finite Element (FE) analysis combined with MRI image analysis. Four FE models were created through 3D reconstruction model made from buttock-thigh MRI images, which were obtained in an actual sitting posture of a specific subject. The internal von Mises stresses within the gluteus maximus were computed and analyzed with alterations of the gluteus maximus muscle thickness considered in the current study. The results showed that the distributions of the high internal von Mises stresses within the gluteus maximus were gradually decreased with the increase of the gluteus maximus muscle thickness. However, the maximum von Mises stresses within the gluteus maximus were irregularly changed. The current study confirms that the internal von Mises stress relief effects of the FES application for PU prevention may have substantial benefits in terms of reduction of the incidence of the deep-tissue injury. It can be concluded that incorporating the FES system into a rehabilitation and treatment program for individuals who have sitting-related PU wounds may promote the healing progress while maintaining their mobility.
 

    Paper Title, Authors, Abstract (Issue 2, Volume 3, 2009)

Pages

Two Phase Brushless D.C. Motor For Artificial Heart Applications
Abdel-Karim Daud

Abstract: The paper presents a performance analysis of brushless d.c. motor (BLDCM) with two air gap windings for a left ventricular heart assist system. The medical system consists of a bloodpump, a centrifugal pump, a brushless d.c. motor, a solenoid, power supply and controls. The brushless d.c. motor operates sensorless and is developed with respect to the special requirements of an implantable heart assist device. Here should be investigated the effect of rotor magnet design on artificial heart driving motor performance, in which rotors with different magnet lengths or thicknesses, as well as different peripheral angles, were designed and simulated in the same motor stator with different rotating speeds. This simulation is based on the calculation of the air-gap flux density of the motor, which is obtained by using three dimensional analytical field method. Then the motor efficiency was computed. MATLAB was used to implement the procedures to calculate the required parameters. The results demonstrated that the reduction of rotor magnet size and the enlargement of the air gap between the rotor magnets and the stator coil core have no significant effect on motor efficiency, but will reduce the torque value on which the motor achieves the highest efficiency; it could be remedied however by increasing the rotating speed, because the torque at the high efficiency point will increase along with the rotating speed. These results may provide a basis for developing small rotor magnets, large air gap and high efficiency motors for driving an artificial heart pump.
 

Hybrid Wireless Sensor Network for Homecare Monitoring of Chronic Patients
Radu Dobrescu, Dan Popescu, Maximilian Nicolae, Stefan Mocanu

Abstract: The paper presents a hybrid wireless sensor network which contains both mobile and fixed nodes, which enables the monitoring of chronic patients and their home environment via normal or, if necessary, emergency communication with longdistance transmitting system like Internet. Each patient and his/her home compose a hybrid node, i.e. a sensor node pair, one for patient (mobile) and one for his/her environment (mobile or fixed). The hybrid node is integrated in a real-time homecare monitoring system able to monitor and diagnose patients outside hospital and also to control the home/car ambiance. If the patient is transported by specially equipped car, the hybrid node becomes fully mobile. Because the number of assisted patients is time-dependent, we can consider that the hybrid node belongs to a scalable ad-hoc wireless sensor network (WSN). This WSN covers an administrative delimited area and contains a central fixed node which monitors the patients and emergency communication and also makes decision for the entire network. One can say that the network has three levels: basic (hybrid nodes for chronic patients), medium (general practitioner and ambulances), and high level (specific physicians at hospital and city hall services). Both nodes, mobile and fixed are presented as same as the design stages which drove to respective hardware architecture. From the software architecture it is described the communication engine because of the particularity in its implementation. Several critical tests were made for reliability of the architecture and some of the results are presented.
 

    Paper Title, Authors, Abstract (Issue 3, Volume 3, 2009)

Pages

Electrocardiogram Data Capturing System and Computerized Digitization using Image Processing Techniques
Lai Khin Wee, Yeo Kee Jiar, Eko Supriyanto

Abstract: Electrocardiogram (ECG) is one of the most widely used diagnostic tools for heart diseases nowadays. Nevertheless, the accurate ECG interpretation is essentially required in order to evaluate the valuable information inside the ECG signal. The conventional technique of visual analysis to inspect the ECG signals by doctors or physicians are not effective and time consuming. Therefore, an automatic system which involves digital signal integration and analysis is required. This paper presents the developed software for image capturing from ECG machine by using digital webcam camera and performing analysis on the captured ECG graph in display before sending through the internet network. The implementation of this project is using MATLAB mathematical software (version 7) as well as the signal and image processing toolbox. Test results show that this software able to extract information from ECG image or video based file and the system manage to determine heart rate of captured ECG accurately.
 

A New Distance-based Approach for Phylogenetic Analysis of Protein Sequences
Shengli Zhang, Tianming Wang

Abstract: With the availability of ever-increasing gene and protein sequence data across a large number of species, reconstruction of phylogenetic trees to reveal the evolutionary relationship among those species becomes more and more important. In this paper, we take the physicochemical properties of amino acids into account and introduce the protein feature sequences into phylogenetic analysis by using the Bhattacharyya distance. The phylogenetic trees on the two data sets have illustrated that the proposed approach performs equally well as the other methods do and is more efficient than some of the methods. So our method may be used to complement phylogenetic analysis.
 

    Paper Title, Authors, Abstract (Issue 4, Volume 3, 2009)

Pages

A Neuronal Network Model for Tinnitus and its Management by Sound Therapy
Hirofumi Nagashino, Yohsuke Kinouchi, Ali A. Danesh, Abhijit S. Pandya

Abstract: Tinnitus is a state in which one hears sounds in the ear or head without any external source. Sound therapy is one of the most effective techniques for tinnitus treatment that have been proposed. In order to investigate mechanisms of tinnitus generation and the clinical effects of sound therapy from neural engineering point of view, we have proposed computational models with plasticity and inhibitory feedback using a neural oscillator or a neuronal network model described by simplified Hodgkin-Huxley equations. In the present paper, the simulation results of the neuronal network model are described. The model is able to replicate the clinical results that human auditory system temporarily halts perception of tinnitus following sound therapy.
 

Computer-Aided Mass Detection on Digitized Mammograms using a Novel Hybrid Segmentation System
N. Riyahi Alam, F. Younesi, M. S. Riyahi Alam

Abstract: A Novel hybrid segmentation method has been developed for detection of masses in digitized mammograms using three parallel approaches: adaptive thresholding method, Gabor filtering and fuzzy entropy feature as a computer-aided detection(CAD) scheme. The algorithm consists of the following steps: a) Preprocessing of the digitized mammograms including identification of region of interest (ROI) as candidate for massive lesion through breast region extraction, b) Image enhancement using linear transformation and subtracting enhanced from the original image, c) Characterization of the ROI by extracting the fuzzy entropy feature, d) Local adaptive thresholding for segmentation of mass areas, e) Filtering the input images using Gabor functions, f) Combine expert of the last three parallel approaches for mass detection. The proposed method was tested on 78 mammograms (30 normal & 48 cancerous) from the BIRADS and local databases. The detected regions validated by comparing them with the radiologists’ hand-sketched boundaries of real masses. The current algorithm can achieve a sensitivity of 90.73% and specificity of 89.17%. This approach showed that the behavior of local adaptive thresholding, Gabor filters and fuzzy entropy technique could be useful for mass detection on digitized mammograms. Our results suggest that the proposed method could help radiologists as a second reader in mammographic screening of masses.