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Numerical Modeling and Computer Simulation of a Meander Line Antenna for Alzheimer’s Disease Treatment, a Feasibility Study
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作者 Felipe P. Perez Maryam Rahmani +8 位作者 Jorge Morisaki Farhan Amran Syazwani Bakri Akmal Halim Alston Dsouza Nurafifi Mohd Yusuff Amran Farhan James Maulucci maher rizkalla 《Journal of Biosciences and Medicines》 CAS 2023年第2期177-185,共9页
Alzheimer’s disease (AD) is a brain disorder that eventually causes memory loss and the ability to perform simple cognitive functions;research efforts within pharmaceuticals and other medical treatments have minimal ... Alzheimer’s disease (AD) is a brain disorder that eventually causes memory loss and the ability to perform simple cognitive functions;research efforts within pharmaceuticals and other medical treatments have minimal impact on the disease. Our preliminary biological studies showed that Repeated Electromagnetic Field Stimulation (REFMS) applying an EM frequency of 64 MHz and a specific absorption rate (SAR) of 0.4 - 0.9 W/kg decrease the level of amyloid-β peptides (Aβ), which is the most likely etiology of AD. This study emphasizes uniform E/H field and SAR distribution with adequate penetration depth penetration through multiple human head layers driven with low input power for safety treatments. In this work, we performed numerical modeling and computer simulations of a portable Meander Line antenna (MLA) to achieve the required EMF parameters to treat AD. The MLA device features a low cost, small size, wide bandwidth, and the ability to integrate into a portable system. This study utilized a High-Frequency Simulation System (HFSS) in the design of the MLA with the desired characteristics suited for AD treatment in humans. The team designed a 24-turn antenna with a 60 cm length and 25 cm width and achieved the required resonant frequency of 64 MHz. Here we used two numerical human head phantoms to test the antenna, the MIDA and spherical head phantom with six and seven tissue layers, respectively. The antenna was fed from a 50-Watt input source to obtain the SAR of 0.6 W/kg requirement in the center of the simulated brain tissue layer. We found that the E/H field and SAR distribution produced was not homogeneous;there were areas of high SAR values close to the antenna transmitter, also areas of low SAR value far away from the antenna. This paper details the antenna parameters, the scattering parameters response, the efficiency response, and the E and H field distribution;we presented the computer simulation results and discussed future work for a practical model. 展开更多
关键词 Alzheimer’s Disease Meander Line Antenna HFSS EMF Linearity SAR Field Distribution
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Electromagnetic and Thermal Simulations of Human Neurons for SAR Applications 被引量:2
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作者 Felipe Perez Gilbert Millholland +6 位作者 Seshasai Vamsi Krishna Peddinti Ashok Kumar Thella James rizkalla Paul Salama maher rizkalla Jorge Morisaki maher E. rizkalla 《Journal of Biomedical Science and Engineering》 2016年第9期437-444,共8页
The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by H... The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by HN for medical diagnosis and treatment. Research issues including the wave frequency, power intensity, reflections and scattering, and penetration depths are of important considerations to be incorporated into the research study. In this study, computer simulation for the EM exposure to HN was studied for the purpose of determining the upper limits of the electric and magnetic field intensities, power consumption, reflections and transmissions, and the change in temperature resulting from the power absorption by human neurons. Both high frequency structural simulators (HFSS) from ANSYS software, and COMSOL multi-physics were used for the simulation of the EM transmissions and reflections, and the temperature profile within the cells, respectively. For the temperature profile estimation, the study considers an electrical source of 0.5 watt input power, 64 MHz. The EM simulation was looking into the uniformity of the fields within the sample cells. The size of the waveguide was set to be appropriate for a small animal model to be conducted in the future. The incident power was fully transmitted throughout the waveguide, and less than 1% reflections were observed from the simulation. The minimum reflected power near the sample under investigation was found to be with negligible reflected field strengths. The temperature profile resulting from the COMSOL simulation was found to be near 0.25 m°K, indicating no change in temperature on the neuro cells under the EM exposure. The paper details the simulation results for the EM response determined by HFSS, and temperature profile simulated by COMSOL. 展开更多
关键词 EM (Electromagnetic) SAR (Specific Absorption Rate) COMSOL HFSS HN (Human Neuron)
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Computer Simulation/Practical Models for Human Thyroid Thermographic Imaging 被引量:1
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作者 James rizkalla William Tilbury +3 位作者 Ahdy Helmy Vinay Kumar Suryadevara maher rizkalla Michael M. Holdmann 《Journal of Biomedical Science and Engineering》 2015年第4期246-256,共11页
We have demonstrated a successful computer model utilizing ANSIS software that is verified with a practical model using Infrared (IR) sensors. The simulation model incorporates the three heat transfer coefficients: co... We have demonstrated a successful computer model utilizing ANSIS software that is verified with a practical model using Infrared (IR) sensors. The simulation model incorporates the three heat transfer coefficients: conduction, convection, and radiation. While the conduction component was a major contributor to the simulation model, the other two coefficients have added to the accuracy and precision of the model. Convection heat allows for the influence of blood flow within the study, while the radiation aspect, sensed through IR sensors, links the practical model of the study. This study also compares simulation data with the applied model generated from IR probe sensors. These sensors formed an IR scanner that moved via servo mechanical system, tracking the temperature distribution within and around the thyroid gland. These data were analyzed and processed to produce a thermal image of the thyroid gland. The acquired data were then compared with an Iodine uptake scan for the same patients. 展开更多
关键词 THYROID THERMOGRAPHY COMPUTER Simulation IMAGING PRACTICAL Model IR SENSORS
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Raman spectroscopy for human cancer tissue diagnosis: A pattern recognition approach 被引量:1
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作者 maher rizkalla Parvin Ghane +2 位作者 Mangilal Agarwal Sudhir Shrestha Kody Varahramyan 《Journal of Biomedical Science and Engineering》 2012年第12期892-900,共9页
In this work, optical scattering using Raman spectroscopy has been analyzed for various cancer tissues. The Raman shifts obtained at the Indiana University Bloomington (IUB) and Indiana University-Purdue University In... In this work, optical scattering using Raman spectroscopy has been analyzed for various cancer tissues. The Raman shifts obtained at the Indiana University Bloomington (IUB) and Indiana University-Purdue University Indianapolis (IUPUI) laboratories have been processed for diagnosing various types of cancer tissues. The objective of this research is to distinguish between cancerous and non-cancerous tissues. Small size tissue samples have been processed, seeking the minimum size tissue that can be diagnosed via Raman spectroscopy. The tests have been conducted on nearly 20 human tissues. A Matlab program has been written following Parzen-Window classifier to recognize the Raman shift pattern for various types of cancer tissues, including breast cancer, kidney, and Gyn-Uterus. A software visual model has been used for data processing. Unique signals for breast and kidney tumors have been obtained. The approach followed in this paper shows promise for early cancer detection in humans. 展开更多
关键词 Cancer TISSUES RAMAN SPECTROSCOPY Pattern Recognition
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EMF Antenna Exposure on a Multilayer Human Head Simulation for Alzheimer Disease Treatments 被引量:1
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作者 Felipe P. Perez Maryam Rahmani +10 位作者 John Emberson Makenzie Weber Jorge Morisaki Farhan Amran Syazwani Bakri Akmal Halim Alston Dsouza Nurafifi Mohd Yusuff Amran Farhan James Maulucci maher rizkalla 《Journal of Biomedical Science and Engineering》 2022年第5期129-139,共11页
In this paper, we follow up with our preliminary biological studies that showed that Repeated electromagnetic field stimulation (REMFS) decreased the toxic amyloid-beta (Aβ) levels, which is considered to be the caus... In this paper, we follow up with our preliminary biological studies that showed that Repeated electromagnetic field stimulation (REMFS) decreased the toxic amyloid-beta (Aβ) levels, which is considered to be the cause of Alzheimer’s disease (AD). The REMFS parameters of these exposures were a frequency of 64 MHz and a Specific absorption rate (SAR) of 0.4 to 0.9 W/Kg in primary human neuronal cultures. In this work, an electromagnetic field (EMF) model was simulated using high-frequency simulation system (HFSS/EMPro) software. Our goal was to achieve the EM parameters (EMF Frequency and SAR) required to decrease the toxic Aβ levels in our biological studies in a simulated human head. The simulations performed here will potentially lead to the successful development of an exposure system to treat Alzheimer’s disease patients. A popular VFH (very high frequency) patch microstrip antenna system was considered in the study. The selection was based on simple and easy construction and appropriateness to the VHF applications. The evaluation of the SAR and temperature distribution on the various head layers, including skin, fat, dura, the cerebrospinal (CSF), and grey matter, brain tissues, were determined for efficacy SAR and safety temperature increase on a simulated human head. Based on a current pulse of 1 A peak current fed to the antenna feeder, a maximum SAR of 0.6 W/Kg was achieved. A range of 0.4 to 0.6 SAR was observed over the various layers of the simulated human head. The initial design of the antenna indicated an antenna size in the order of 1 m in length and width, suggesting a stationary practical model for AD therapy. Future direction is given for wearable antenna and exposure system, featuring high efficiency and patient comfort. 展开更多
关键词 EM ANTENNA Brain Tissues SIMULATION ALZHEIMER
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Hardware Design for Low Power Integrated Sensor System
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作者 maher rizkalla An Feng +6 位作者 Michael Knieser Francis Bowen Paul Salama Brian King Jasmin Radadia Sarang Gadkari Hossein Jafarian 《International Journal of Communications, Network and System Sciences》 2012年第3期141-146,共6页
An integrated sensor system is implemented using inter-integrated circuit mode (I2C) software, utilizing the PIC182585 MPLAB embedded control system utilizing hardware. The hardware implementation features high level ... An integrated sensor system is implemented using inter-integrated circuit mode (I2C) software, utilizing the PIC182585 MPLAB embedded control system utilizing hardware. The hardware implementation features high level of integration, reliability, high precision, and high speed communications. The system was demonstrated by temperature and CO2 sensors. An extension for Zigbee system is proposed to enhance the security of the integrated system. A bi-directional air/liquid flow sensor is also added to detect the flow magnitude and direction that can be applied to heating, ventilating, and air-conditioning (HVAC), local and national security within subway systems, and medical equipment. The hardware design of the flow sensor included one heating element and two sensing elements to detect the bi-directional flow. Platinum sensors were found to be of high sensitivity and linear characteristics within 0℃ to 100℃ range, and their high temperature coefficient (0.00385 Ω/Ω/℃). Polyimide thin film heater was used as the heating element due to its high throughput and good thermal efficiency. Two bridge circuits were also designed to sense the temperature distribution in the vicinity of the sensing elements. Three high precision instrumentation low power amplifiers with offset voltage ~2.5 μV (50 μV max) were used for the overall design. The system security is also enhanced with the detection of poison gas using Carbon Nanotube devices (CNT). An antenna system was designed, and a frequency shift was detected to designate the type of poison gas used for a general threat. 展开更多
关键词 Smart Sensors Embedded Systems HVAC PIC18 MICROPROCESSOR I2C Bus BIDIRECTIONAL AIRFLOW Wireless
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Electromagnetic Simulation for the Diagnosis of Lipoprotein Density in Human Blood, a Non-Invasive Approach
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作者 Ethan Law Monika Kakani +1 位作者 Mangilal Agarwal maher rizkalla 《Open Journal of Applied Biosensor》 2017年第1期1-11,共11页
With the rise in prevalence of Type II diabetes throughout the world, an increasing need for a portable monitoring system for both blood glucose and lipoprotein concentrations is in demand. Recent work has led to non-... With the rise in prevalence of Type II diabetes throughout the world, an increasing need for a portable monitoring system for both blood glucose and lipoprotein concentrations is in demand. Recent work has led to non-invasive wearable devices for monitoring changes in blood glucose concentrations using electromagnetic (EM) waves. However, this still fall short as a means of monitoring cholesterol levels in diabetic patients. The EM study on human tissues emphasized here may also relate to the safety guidelines applied to cellular communications, power lines, and other EM applications. The specific absorption rate (SAR) for the power of the non-ionizing frequency must not exceed a threshold as it impacts DNA and can lead to cancerous tissues. In this study, we used COMSOL software for the investigation of the viability of using EM within the frequency range of 64 MHz-1 GHz as a means of monitoring the transmission properties of human blood and lipoprotein. In this approach, wave equations were solved within blood and lipoprotein boundaries. Research parameters, including frequency range, Power input (SAR), and lipoprotein densities, were investigated. The transmission properties, produced by the electrical and thermal characteristics of these physiological parameters, have led to proper diagnosis of lipoprotein density. Within the frequency range of 64 MHz to 1 GHz, and for a power range of 0.1 to 0.6 SAR, lipoprotein density from 1.00 g/mL to 1.20 g/mL was considered. A 2D model, with an antenna source that supplied the electromagnetic waves to human tissues, was created for the simulations. These were used for the study of the transmission properties of the EM energy into the blood and lipoprotein tissues. While the range of magnetic flux values between simulations varies only slightly or not at all, the distribution of these values is impacted by given parameters. As such, a device capable of comparing magnetic flux values and penetration depths could easily distinguish between samples of different lipoprotein densities. The results obtained in this study can be accommodated non-invasively by human tissues, and can be produced in a practical model using wearable devices. A practical model is proposed for future consideration. 展开更多
关键词 NON-INVASIVE Monitoring CHOLESTEROL ELECTROMAGNETIC Biosensors WEARABLE Devices
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Smartphone Based Fall Detection and Logic Testing Application Using Android SDK
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作者 Vinay Kumar Suryadevara maher rizkalla 《Journal of Biomedical Science and Engineering》 2015年第9期616-624,共9页
Smart systems aimed at detecting the fall of a person have increased significantly due to recent technological advances and availability of modular electronics. This work presents the use of embedded accelerometer and... Smart systems aimed at detecting the fall of a person have increased significantly due to recent technological advances and availability of modular electronics. This work presents the use of embedded accelerometer and gyroscope in mobile phones to accurately detect and classify the type of fall a person is experiencing before suffering an impact. Early classification of fall type helps in optimizing the algorithm of the fall detection. User acceptance, feasibility and the limitations in the accuracy of the existing devices have also been considered in this study. High efficiency and low power approaches were emphasized with wireless capability that enhanced the system performance for variety of applications. There is a need of reducing the time for analyzing the smart algorithms designed. It is also emphasized that this application will be a good platform that can be used to test various algorithms and multiple sensors at a time with ease and obtain data analysis in a short period. 展开更多
关键词 ACCELEROMETER SMARTPHONE ANDROID EMBEDDED Systems Wireless SENSORS
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Numerical Analysis and Design of an EMF Birdcage Wearable Device for the Treatment of Alzheimer’s Disease: A Feasibility Study
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作者 Felipe P. Perez David Michael Arvidson +2 位作者 Tyler Phoenix Taylor Maryam Rahmani maher rizkalla 《Journal of Biomedical Science and Engineering》 CAS 2022年第8期219-227,共9页
In this study, we performed a numerical analysis of a novel EMF Birdcage wearable device for the treatment of Alzheimer’s disease (AD). We designed the new device to generate and radiate a frequency of 64 MHz and a s... In this study, we performed a numerical analysis of a novel EMF Birdcage wearable device for the treatment of Alzheimer’s disease (AD). We designed the new device to generate and radiate a frequency of 64 MHz and a specific absorption rate (SAR) of 0.6 W/kg to a simulated human brain tissue. We determined these parameters from our experimental studies on primary human brain cultures at the Indiana University School of Medicine (IUSM). We found that this frequency and SAR decreased the toxic Aβ levels in the cell cultures. The frequency of 64 MHZ has good skin depth penetration, which will easily pass through the various head layers, including hair, skin, fat, dura, the cerebrospinal (CSF), and grey matter, and reach deeply into the brain tissues. The SAR of 0.6 W/kg was achieved with lower power input and energy, decreasing the probability of thermal injury. Therefore, these parameters enhance the safety of these potential treatments. This Birdcage device emulates a small-scale MRI machine, producing the same 64 MHz frequency at much lower operating input power. In this work, we utilized a high-frequency simulation system (HFSS/EMPro) software to produce the birdcage structure for the required EMF parameters. The 64 MHz radiating frequency produced the scattering S11 parameter of −15 dbs. We obtained a SAR of 0.6 W/kg when an input power of 100 W was applied. The coil dimensions were found to be near 15 cm in height and 22 cm in diameter, which fits in wearable systems. We found that the distribution of the electric field and SAR radiate homogeneously over the simulated human head with good penetration into the brain, which proves to be an appropriate potential therapeutic strategy for Alzheimer’s disease. 展开更多
关键词 Alzheimer Disease Birdcage TREATMENT HFSS EMF Temperature
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High Sensitive Graphene Devices for Non-Invasive Early Diagnosis of Hyperthyroidism: A Feasibility Study
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作者 Avinash Yadav Inayeth Ali +1 位作者 Ahdy Helmy maher rizkalla 《Journal of Biomedical Science and Engineering》 2019年第12期522-532,共11页
This paper presents a novel approach with Graphene devices that are highly sensitive in detecting IR energy. Current non-imaging techniques like ultrasonography have been proposed for thyroid diagnosis with limitation... This paper presents a novel approach with Graphene devices that are highly sensitive in detecting IR energy. Current non-imaging techniques like ultrasonography have been proposed for thyroid diagnosis with limitations on ability to detect low-temperature distribution around the hot spot at the starting stage of the thyroid hyperthyroidism. The energy distribution around hotspot is minimal at the beginning stage. This detection may require ultra-high sensitive materials to the IR energy. A computer modeling using COMSOL software shows the thermal energy simulation of a thyroid gland with single or multiple active nodules. Data collection of the energy levels and condition of thyroid in the human body support the work investigated in this study. The study conducted here has shown as low as 0.1 - 5 mW IR power can be detected based on the Graphene device sensitivity. The paper details the simulation and approach for this non-invasive diagnosis. 展开更多
关键词 Diagnosis NON-INVASIVE GNRFET THERMOGRAPHY ULTRASONOGRAPHY IoT
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DSPs/FPGAs Comparative Study for Power Consumption, Noise Cancellation, and Real Time High Speed Applications
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作者 Alon Hayim Michael Knieser maher rizkalla 《Journal of Software Engineering and Applications》 2010年第4期391-403,共13页
Adaptive noise data filtering in real-time requires dedicated hardware to meet demanding time requirements. Both DSP processors and FPGAs were studied with respect to their performance in power consumption, hardware a... Adaptive noise data filtering in real-time requires dedicated hardware to meet demanding time requirements. Both DSP processors and FPGAs were studied with respect to their performance in power consumption, hardware architecture, and speed for real time applications. For testing purposes, real time adaptive noise filters have been implemented and simulated on two different platforms, Motorola DSP56303 EVM and Xilinx Spartan III boards. This study has shown that in high speed applications, FPGAs are advantageous over DSPs with respect of their speed and noise reduction because of their parallel architecture. FPGAs can handle more processes at the same time when compared to DSPs, while the later can only handle a limited number of parallel instructions at a time. The speed in both processors impacts the noise reduction in real time. As the DSP core gets slower, the noise removal in real time gets harder to achieve. With respect to power, DSPs are advantageous over FPGAs. FPGAs have reconfigurable gate structure which consumes more power. In case of DSPs, the hardware has been already configured, which requires less power consumption? FPGAs are built for general purposes, and their silicon area in the core is bigger than that of DSPs. This is another factor that affects power consumption. As a result, in high frequency applications, FPGAs are advantageous as compared to DSPs. In low frequency applications, DSPs and FPGAs both satisfy the requirements for noise cancelling. For low frequency applications, DSPs are advantageous in their power consumption and applications for the battery power devices. Software utilizing Matlab, VHDL code run on Xilinix system, and assembly running on Motorola development systems, have been used for the demonstration of this study. 展开更多
关键词 Four QUADRANT (4Q) Converter INTERLACING TRACTION Systems Power Quality Analysis
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Efficient Fast Multiplication Free Integer Transformation for the 1-D DCT of the H.265 Standard
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作者 Mohamed Nasr Haggag Mohamed El-Sharkawy +1 位作者 Gamal Fahmy maher rizkalla 《Journal of Software Engineering and Applications》 2010年第8期784-795,共12页
In this paper, efficient one-dimensional (1-D) fast integer transform algorithms of the DCT matrix for the H.265 stan-dard is proposed. Based on the symmetric property of the integer transform matrix and the matrix op... In this paper, efficient one-dimensional (1-D) fast integer transform algorithms of the DCT matrix for the H.265 stan-dard is proposed. Based on the symmetric property of the integer transform matrix and the matrix operations, which denote the row/column permutations and the matrix decompositions, along with using the dyadic symmetry modification on the standard matrix, the efficient fast 1-D integer transform algorithms are developed. Therefore, the computational complexities of the proposed fast integer transform are smaller than those of the direct method. In addition to computational complexity reduction one of the proposed algorithms provides transformation quality improvement, while the other provides more computational complexity reduction while maintaining almost the same transformation quality. With lower complexity and better transformation quality, the first proposed fast algorithm is suitable to accelerate the quality-demanding video coding computations. On the other hand, with the significant lower complexity, the second proposed fast algorithm is suitable to accelerate the video coding computations. 展开更多
关键词 FAST Algorithm HDTV H.265 ICT Order-16 TRANSFORM Video Coding
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VLSI Implementation for Low Noise Power Efficiency Cellular Communication Systems
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作者 Rondia MACK maher rizkalla +1 位作者 Paul SALAMA Mohamed EL-SHARKAWY 《Wireless Sensor Network》 2010年第1期18-30,共13页
A low power model for Code Division Multiple Access (CDMA) based cellular communication system is developed. The dynamic power is minimized by reducing the frequency of the Phase Lock Loop (PLL) after lock is establis... A low power model for Code Division Multiple Access (CDMA) based cellular communication system is developed. The dynamic power is minimized by reducing the frequency of the Phase Lock Loop (PLL) after lock is established. The paper addresses the feasibility of lowering the clock frequency of the processing unit that models the PLL is addressed and modulator/demodulator functions of the system while maintaining synchronization with the memory unit and other peripherals. The system is simulated with Matlab considering various Signal-to-Noise Ratios (SNR). For a given SNR, the minimum frequency required for the PLL to maintain lock is determined. The Matlab file is translated to VHDL code, simulated and synthesized with Mentor tools, and the layout then generated. Mach-Pa 5-V software system from Mentor tools is utilized to estimate the power consumed by the simulated device. A Xilinx file is also generated and downloaded for Field Programmable Gate Arrays (FPGA) implementation. A 50 MHz clock frequency of the processing unit was first considered and then lowered to 20 MHz for the low power study. Lowering the base and clock frequency resulted in near 30% reduction in power. 展开更多
关键词 CELLULAR COMMUNICATION CDMA PLL Harware XILINX Matlab Low Power
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Fast Implementation of VC-1 with Modified Motion Estimation and Adaptive Block Transform
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作者 Michael Tammen Mohamed El-Sharkawy +1 位作者 Hisham Sliman maher rizkalla 《Circuits and Systems》 2010年第1期12-17,共6页
The Society of Motion Picture and Television Engineers (SMPTE) Standard 421M, commonly known as VC-1, is a state-of-the-art video compression format that provides highly competitive video quality, from very low throug... The Society of Motion Picture and Television Engineers (SMPTE) Standard 421M, commonly known as VC-1, is a state-of-the-art video compression format that provides highly competitive video quality, from very low through very high bit rates, at a reasonable computational complexity. First, this paper presents fast motion compensation methods. The four motion estimation methods examined are fast, three step search, varying diamond, and 2D logarithmic. These methods use less search points than the full spiral scan used in the VC-1 reference software, which allows for faster motion estimation. Second, this paper presents a residual texture based choice of the block size for the Discrete Cosine Transform (DCT). To determine the block size, data is examined after the residual texture has been calculated. This is in contrast to the VC-1 reference software, which uses calculations at the block level to determine the block size. The residual texture of each block is small and uniform, allowing for simplified block choices. 展开更多
关键词 VC-1 Motion Estimation DISCRETE COSINE TRANSFORM VIDEO Compression
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Microwave/Thermal Analyses for Human Bone Characterization
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作者 Vinay Kumar Suryadevara Suyog Patil +3 位作者 James rizkalla Ahdy Helmy Paul Salama maher rizkalla 《Journal of Biomedical Science and Engineering》 2016年第2期101-111,共11页
A novel imaging approach utilizing microwave scattering was proposed in order to analyze various properties of bone. Microwave frequencies of 900 MHz, 1 GHz, and 2.4 GHz were used during this study. This investigation... A novel imaging approach utilizing microwave scattering was proposed in order to analyze various properties of bone. Microwave frequencies of 900 MHz, 1 GHz, and 2.4 GHz were used during this study. This investigation’s objectives were to emphasize characteristics of abnormalities in human bones and to detect fine fractures through contrasts in bone density. The finite element method (FEM) presented here is generated from COMSOL software at different frequencies. The study identified the optimum transmission directed at the interface layers from an external microwave source. It was found that approximately 900 MHz microwave power was ideal for this application. This can be attributed to the penetration depth where the power dissipation is analyzed based on bone condition. The microwave energy was generated from an exterior antenna that was interfaced, via catheter, to skeletal bone. The power transmitted to bone was converted into thermal energy, and has led to a visible temperature distribution pattern, which reflects the bone density level, and accordingly, the type of bone under investigation. The electrical and thermal properties, including the dielectric permittivity, thermal conductivity, and heat flux absorption through the bone substance, have great implications on the FEM distribution. The boundary conditions using tangential matching of field components at the tissue-bone interface were incorporated into the finite element method. The average power from the electromagnetic fields (estimated from the Poynting’s vector, P = E*H), was assumed to be fully absorbed as heat due to the conductivity of the bone material. Furthermore, microwave energy was applied as a delta function and the thermal distributions have been analyzed in order to distinguish between normal healthy bone and bones with structural or metabolic abnormalities. The latter was emulated by different bone density to contrast normal bone anatomy. The FEM simulation suggests that thermography microwave imaging could be a good tool for bone characterization in order to detect skeletal abnormalities. This approach could be advantageous over other existing methods such as X-ray imaging. 展开更多
关键词 MICROWAVE Human Bones SIMULATION FEM COMSOL THERMAL DIAGNOSIS
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Eletromagnetic Detection of Mild Brain Injury: A Novel Imaging Approach to Post Concussive Syndrome
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作者 James rizkalla David Botros +4 位作者 Nasser Alqahtani Mounica Patnala Paul Salama Felipe Pablo Perez maher rizkalla 《Journal of Biomedical Science and Engineering》 2021年第11期347-360,共14页
<strong>Introduction</strong><strong>:</strong> Mild traumatic brain injury (mTBI) is a common injury, with nearly 3 - 4 million cases annually in the United States alone. Neuroimaging in patie... <strong>Introduction</strong><strong>:</strong> Mild traumatic brain injury (mTBI) is a common injury, with nearly 3 - 4 million cases annually in the United States alone. Neuroimaging in patients with mTBI provides little benefit, and is usually not indicated as the diagnosis is primarily clinical. It is theorized that microvascular trauma to the brain may be present in mTBI, that may not be captured by routine MRI and CT scans. Electromagnetic (EM) waves may provide a more sensitive medical imaging modality to provide objective data in the diagnosis of mTBI. <strong>Methods:</strong> COMSOL simulation software was utilized to mimic the anatomy of the human skull including skin, cranium, cerebrospinal fluid (CSF), gray-matter tissue of the brain, and microvasculature within the neural tissue. The effects of penetrating EM waves were simulated using the finite element analysis software and results were generated to identify feasibility and efficacy. Frequency ranges from 7 GHz to 15 GHz were considered, with 0.6 and 1 W power applied.<strong> Results:</strong> Variations between the differing frequency levels generated different energy levels within the neural tissue—particularly when comparing normal microvasculature versus hemorrhage from microvasculature. This difference within the neural tissue was subsequently identified, via simulation, serving as a potential imaging modality for future work. <strong>Conclusion: </strong>The use of electromagnetic imaging of the brain after concussive events may play a role in future mTBI diagnosis. Utilizing the proper depth frequency and wavelength, neural tissue and microvascular trauma may be identified utilizing finite element analysis. 展开更多
关键词 Brain Injury TRAUMA IMAGING Simulation COMSOL
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TSUNAMI:Translational Bioinformatics Tool Suite for Network Analysis and Mining
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作者 Zhi Huang Zhi Han +6 位作者 Tongxin Wang Wei Shao Shunian Xiang Paul Salama maher rizkalla Kun Huang Jie Zhang 《Genomics, Proteomics & Bioinformatics》 SCIE CAS CSCD 2021年第6期1023-1031,共9页
Gene co-expression network(GCN)mining identifies gene modules with highly correlated expression profiles across samples/conditions.It enables researchers to discover latent gene/molecule interactions,identify novel ge... Gene co-expression network(GCN)mining identifies gene modules with highly correlated expression profiles across samples/conditions.It enables researchers to discover latent gene/molecule interactions,identify novel gene functions,and extract molecular features from certain disease/condition groups,thus helping to identify disease bio-markers.However,there lacks an easy-to-use tool package for users to mine GCN modules that are relatively small in size with tightly connected genes that can be convenient for downstream gene set enrichment analysis,as well as modules that may share common members.To address this need,we developed an online GCN mining tool package:TSUNAMI(Tools SUite for Network Analysis and MIning).TSUNAMI incorporates our state-of-the-art lmQCM algorithm to mine GCN modules for both public and user-input data(microarray,RNA-seq,or any other numerical omics data),and then performs downstream gene set enrichment analysis for the identified modules.It has several features and advantages:1)a user-friendly interface and real-time co-expression network mining through a web server;2)direct access and search of NCBI Gene Expression Omnibus(GEO)and The Cancer Genome Atlas(TCGA)databases,as well as user-input gene ex-pression matrices for GCN module mining;3)multiple co-expression analysis tools to choose from,all of which are highly flexible in regards to parameter selection options;4)identified GCN modules are summarized to eigengenes,which are convenient for users to check their correlation with other clinical traits;5)integrated downstream Enrichr enrichment analysis and links to other gene set enrichment tools;and 6)visualization of gene loci by Circos plot in any step of the process.The web service is freely accessible through URL:https://biolearns.medicine.iu.edu/.Source code is available at https://github.com/huangzhii/TSUNAMI/. 展开更多
关键词 Network mining Gene co-expression network Transcriptomic data analysis lmQCM Web server Survival analysis
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