The Experts below are selected from a list of 6618 Experts worldwide ranked by ideXlab platform
Ronan Sauleau - One of the best experts on this subject based on the ideXlab platform.
-
exposure assessment in millimeter wave reverberation chamber using murine phantoms
Bioelectromagnetics, 2020Co-Authors: Abdou Khadir Fall, Ronan Sauleau, Christophe Lemoine, Philippe Besnier, Yves Le Drean, Maxim ZhadobovAbstract:This study deals with the design and calibration of the first mode-stirred reverberation chamber (RC) in the 60-GHz-band adapted for in vivo bioelectromagnetic studies. In addition to the interface for electromagnetic and thermal dosimetry, the interfaces for lighting and ventilation were integrated into the RC walls while preserving acceptable shielding. The RC with mechanical and electronic steering capabilities is characterized in the 55-65 GHz range. To this end, murine skin-equivalent phantoms of realistic shape were designed and fabricated. Their complex permittivity is within ±12% of the target value of murine skin (6.19-j5.81 at 60 GHz). The quality factor of the RC loaded with an animal cage, bedding litter, and five murine phantoms was found to be 1.2 × 104 . The losses inside the RC were analyzed, and it was demonstrated that the main sources of the power dissipation were the phantoms and mice cage. The input power required to reach the average incident power density of 1 and 5 mW/cm2 was found to be 0.23 and 1.14 W, respectively. Surface heating of the mice models was measured in the infrared (IR) range using a specifically designed interface, transparent at IR and opaque at millimeter waves (mmW). Experimental results were compared with an analytical solution of the heat transfer equation and to full-wave computations. Analytical and numerical results were in very good agreement with measurements (the relative deviation after 90 min of exposure was within 4.2%). Finally, a parametric study was performed to assess the impact of the thermophysical parameters on the resulting heating. Bioelectromagnetics. 2020;41:121-135. © 2020 Bioelectromagnetics Society.
-
enhancing exposure efficiency and uniformity using a choke ring antenna application to bioelectromagnetic studies at 60 ghz
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: A V Boriskin, Maxim Zhadobov, Yves Le Drean, S Steshenko, Christian Person, Ronan SauleauAbstract:An effective solution for increasing the exposure uniformity and efficiency of biological samples in in vitro bioelectromagnetic experiments at 60 GHz is proposed by introducing a novel choke ring antenna (CRA). The CRA is optimized to provide a uniform exposure of samples, whose dimensions are equivalent to those of a standard 35-mm Petri dish, positioned close to the antenna aperture, i.e., 10–20 wavelengths. The antenna prototype is fabricated in metallized foam. The realized exposure efficiency of the sample exceeds 55% (if estimated for an exposure uniformity better than ${-}$ 0.5 dB). To validate the numerical results, the field intensity profiles on the surface of a high-water-content phantom have been experimentally obtained using a high-resolution infrared camera. Compared to the standard open-ended waveguide and horn antennas, typically used for millimeter-wave dosimetry, a twofold advantage of the proposed CRA is demonstrated, namely, the improvement of the exposure efficiency by a factor of 1.5 to 2 with a simultaneous reduction of the exposure distance by a factor of 8–2, respectively, depending on the type of the reference antenna. These advantages make the proposed CRA an excellent candidate for 60-GHz short-range exposure systems for in vitro bioelectromagnetic studies.
Maxim Zhadobov - One of the best experts on this subject based on the ideXlab platform.
-
exposure assessment in millimeter wave reverberation chamber using murine phantoms
Bioelectromagnetics, 2020Co-Authors: Abdou Khadir Fall, Ronan Sauleau, Christophe Lemoine, Philippe Besnier, Yves Le Drean, Maxim ZhadobovAbstract:This study deals with the design and calibration of the first mode-stirred reverberation chamber (RC) in the 60-GHz-band adapted for in vivo bioelectromagnetic studies. In addition to the interface for electromagnetic and thermal dosimetry, the interfaces for lighting and ventilation were integrated into the RC walls while preserving acceptable shielding. The RC with mechanical and electronic steering capabilities is characterized in the 55-65 GHz range. To this end, murine skin-equivalent phantoms of realistic shape were designed and fabricated. Their complex permittivity is within ±12% of the target value of murine skin (6.19-j5.81 at 60 GHz). The quality factor of the RC loaded with an animal cage, bedding litter, and five murine phantoms was found to be 1.2 × 104 . The losses inside the RC were analyzed, and it was demonstrated that the main sources of the power dissipation were the phantoms and mice cage. The input power required to reach the average incident power density of 1 and 5 mW/cm2 was found to be 0.23 and 1.14 W, respectively. Surface heating of the mice models was measured in the infrared (IR) range using a specifically designed interface, transparent at IR and opaque at millimeter waves (mmW). Experimental results were compared with an analytical solution of the heat transfer equation and to full-wave computations. Analytical and numerical results were in very good agreement with measurements (the relative deviation after 90 min of exposure was within 4.2%). Finally, a parametric study was performed to assess the impact of the thermophysical parameters on the resulting heating. Bioelectromagnetics. 2020;41:121-135. © 2020 Bioelectromagnetics Society.
-
enhancing exposure efficiency and uniformity using a choke ring antenna application to bioelectromagnetic studies at 60 ghz
IEEE Transactions on Microwave Theory and Techniques, 2013Co-Authors: A V Boriskin, Maxim Zhadobov, Yves Le Drean, S Steshenko, Christian Person, Ronan SauleauAbstract:An effective solution for increasing the exposure uniformity and efficiency of biological samples in in vitro bioelectromagnetic experiments at 60 GHz is proposed by introducing a novel choke ring antenna (CRA). The CRA is optimized to provide a uniform exposure of samples, whose dimensions are equivalent to those of a standard 35-mm Petri dish, positioned close to the antenna aperture, i.e., 10–20 wavelengths. The antenna prototype is fabricated in metallized foam. The realized exposure efficiency of the sample exceeds 55% (if estimated for an exposure uniformity better than ${-}$ 0.5 dB). To validate the numerical results, the field intensity profiles on the surface of a high-water-content phantom have been experimentally obtained using a high-resolution infrared camera. Compared to the standard open-ended waveguide and horn antennas, typically used for millimeter-wave dosimetry, a twofold advantage of the proposed CRA is demonstrated, namely, the improvement of the exposure efficiency by a factor of 1.5 to 2 with a simultaneous reduction of the exposure distance by a factor of 8–2, respectively, depending on the type of the reference antenna. These advantages make the proposed CRA an excellent candidate for 60-GHz short-range exposure systems for in vitro bioelectromagnetic studies.
Gianluca Lazzi - One of the best experts on this subject based on the ideXlab platform.
-
recent advances in computational and experimental Bioelectromagnetics for neuroprosthetics
International Conference on Electromagnetics in Advanced Applications, 2019Co-Authors: John Stang, Guanbo Chen, Pragya Kosta, Javad Paknahad, Manjunath Machnoor, Ege Iseri, Danilo Brizi, Kyle Loizos, Gianluca LazziAbstract:Our group has developed a modular computational framework that integrates in space and time: (1) an admittance/impedance (AM/IM) multiresolution method capable of predicting currents induced in microscale models of nerves due to neurostimulators of arbitrary geometry with (2) a neural simulation environment (NEURON) capable of predicting nerve excitation. This integration is achieved by coupling high-resolution electromagnetic field solutions from our in-house AM/IM solver with neuronal anatomy and biophysics models implemented in NEURON. Furthermore, this AM/IM/NEURON platform utilizes advanced parallel processing and shared memory techniques to optimize computation times and data transfer rates between the two solvers. Leveraging the capabilities of this platform, our group has undertaken a variety of studies ranging from fundamental neuroscience to applied neuroprosthethic design with the common thread of linking our AM/IM/NEURON computational modeling with experimental data to analyze signaling pathways, test hypotheses, and to guide and validate prosthetic designs.
-
Advances in Bioelectromagnetics for implantable systems
2012 IEEE Topical Conference on Biomedical Wireless Technologies Networks and Sensing Systems (BioWireleSS), 2012Co-Authors: Carlos J. Cela, Anil Kumar Ramrakhyani, Sundar Srinivas, Gerard J. Hayes, Michael D. Dickey, Gianluca LazziAbstract:Implantable medical devices are used to supplement, monitor, or replace physiological function for a variety of medical conditions. In this article we highlight a set of topics that we believe could eventually be instrumental in bringing the next generation of implantable devices to existence. These include multi-scale numerical modeling and simulation, magnetic neural interfaces, high-performance telemetry, and the use and application of flexible antennas.
-
Computational and experimental Bioelectromagnetics for a retinal prosthesis
2009 International Conference on Electromagnetics in Advanced Applications, 2009Co-Authors: Gianluca LazziAbstract:Computational and experimental Bioelectromagnetics play an important role in the development of an epi-retinal prosthesis to restore partial vision to the blind. Specifically, the design of telemetry systems for power and data transfer, SAR analysis to ensure safety, and improvement of the effectiveness of the neursotimulator in general are areas of great interest. We will present an overview of the efforts in these areas and highlight the progress made toward the development of an artificial retina. The methods developed or improved over the past decade find also application to the development of implantable neurostimulators in general, thus providing a larger platform for significant impact of computational and experimental Bioelectromagnetics methods to implantable devices.
-
Two-dimensional SPICE-linked multiresolution impedance method for low-frequency electromagnetic interactions
IEEE Transactions on Biomedical Engineering, 2003Co-Authors: M. Eberdt, P.k. Brown, Gianluca LazziAbstract:A multiresolution impedance method for the solution of low-frequency electromagnetic interaction problems typically encountered in Bioelectromagnetics is presented. While the impedance method in its original form is based on the discretization of the scattering objects into equal-sized cells, our formulation decreases the number of unknowns by using an automatic mesh generation method that does not yield equal-sized cells in the modeling space. Results indicate that our multiresolution mesh generation scheme can provide a 50%-80% reduction in cell count, providing new opportunities for the solution of low-frequency bioelectromagnetic problems that require a high level of detail only in specific regions of the modeling space. Furthermore, linking the mesh generator to a circuit simulator such as SPICE permits the addition of arbitrarily complex passive and active circuit elements to the generated impedance network, opening the door to significant advances in the modeling of bioelectromagnetic phenomena.
Ганна Володимирівна Невойт - One of the best experts on this subject based on the ideXlab platform.
-
Evaluation of the human bioelectromagnetic field in medicine: the development of methodology and prospects are at the present scientific stage.
Wiadomosci lekarskie (Warsaw Poland : 1960), 2019Co-Authors: Ozar P. Minser, Ganna V. Nevoit, Озар Петрович Мінцер, Озар Петрович Минцер, М. M. Potiazhenko, Максим Макарович Потяженко, Ганна Володимирівна НевойтAbstract:OBJECTIVE Introduction: The authors focus on the unresolved problem of NCDs and on the relevance of further scientific research in accordance with the current physics-biological level of knowledge about the structure and functioning of the human body. In the course, emphasis is placed on the need for further study of methods for assessing the bioelectromagnetic field of the human body as a potential "tool" for a possible solution of the NCD problem in the framework of system medicine. The aim is to assess the level of development of the methodology and substantiate the scientific feasibility of further exploring the possibilities of the clinical application of these methods for assessing the bioelectromagnetic field of the human body in the algorithms for examining and managing patients with NCDs to study valeological status and objective monitoring of physical phenomena in the clinic of internal diseases. PATIENTS AND METHODS Materials and methods: The analysis of the literature data was carried out in the course of a search study of methods for the rapid assessment of valeological status as a fragment of the initiative research project "Development of algorithms and technology for introducing a healthy lifestyle in patients with non-communicable diseases based on the study of psycho-emotional status" (State registration No. 0116U007798, UDC 613:616-052:159.942:616-03). RESULTS Review: The gnoseological aspect of the development of the methodology for assessing the bioelectric and biomagnetic fields of the human body is described in the article. The conditional time stages of the methodology are highlighted and characterized in it. It was proposed to distinguish between periods: 1) cumulative (XIII-XVIII centuries), 2) cumulative-dynamic (XII-XX centuries), 3) modern (XXI century) 4) modern (prospective). Questions of the feasibility of further research assessing the bioelectromagnetic field of the human body are discussed. CONCLUSION Conclusions: 1. The above gnoseological aspect of the 700-year-old methodology for studying the bioelectromagnetic field of a human body demonstrates a staged evolution of its development, the presence of a significant amount of cumulated scientific information, which requires rethinking as part of system medicine. This convinces us of the existence of a tendency of inevitable approaching the final stage of knowledge of the human bioelectromagnetic field with the widespread introduction of these techniques into the practical public health of the world. 2. The accumulated layer of scientific knowledge about the bioelectromagnetic component of the human body requires integration into fundamental medicine, transformation of the modern paradigm by creating a bioelectromagnetic-chemical concept of the exchange of matter and energy in the human body. 3. Further research on the assessment of the bioelectromagnetic field is relevant and can contribute to solving the NCD problem both at a fundamental level within the framework of system medicine and by optimizing the diagnostic assessment in patient management algorithms during diagnosis, treatment, primary and secondary prevention.
Tomasz Dlugosz - One of the best experts on this subject based on the ideXlab platform.
-
Influence of quasi-spherical polarization on results of bioelectromagnetic studies.
Electromagnetic Biology and Medicine, 2014Co-Authors: Tomasz DlugoszAbstract:AbstractOne of the most interesting questions in bioelectromagnetic and compatibility studies is differences between results of experiments performed in different labs in “identical” conditions, especially in Bioelectromagnetics studies. A reason of these differences may be due to differences in investigated objects, particularly in in vivo experiments. However, the author, as engineer, would like to focus the readers' attention on the technical aspects of exposure systems namely: presence and role of mutual interaction between the object under test and the exposure system, interaction between exposure objects, the role of polarization and the similarity of real-life exposure to those applied in experiments, etc. All these factors may change the results of experiments and lead to false conclusions.
-
Uncertainity analysis of selected sources of errors in bioelectromagnetic investigations.
Bio-Medical Materials and Engineering, 2014Co-Authors: Tomasz DlugoszAbstract:The aim of this paper is to focus attention of experimenters on several sources of error that are not taken into ac- count in the majority of Bioelectromagnetics experiments, and which may lead to complete falsification of the results of the experiments.
-
Exposure systems for bioelectromagnetic experiments
Electromagnetic Biology and Medicine, 2013Co-Authors: Tomasz Dlugosz, Hubert TrzaskaAbstract:AbstractOne of the most interesting questions in Bioelectromagnetics is why there is a difference between results of experiments performed in various labs in “identical” conditions. One of the possible reasons is the difference of investigated objects, especially while performing experiments in vivo. However, the authors, as engineers, would like to focus readers’ attention on the technical aspects of exposure systems, especially the presence and role of mutual interaction between biological objects under test (OUT) and the exposure system, the interactions between the objects, the role of polarization, the similarity of real exposure to that applied in experiments etc. All these factors may alter the results of experiments and lead to false conclusions.
-
numerical models in Bioelectromagnetics
International Conference on Modern Problems of Radio Engineering Telecommunications and Computer Science, 2012Co-Authors: Tomasz Dlugosz, Vitalij Nichoga, Hubert TrzaskaAbstract:The paper deals with problem of possible simplification of numerical models, especially in Bioelectromagnetics, in order to shorten the calculation time and necessary RAM volume. Presented estimations confirm usefulness of presented idea.
-
Is always high-resolution human model in bioelectromagnetic modeling needed?
Open Engineering, 2011Co-Authors: Tomasz DlugoszAbstract:The paper presents short profile of analytical and numerical methods used in bioelectromagnetic modeling. Some comparison of different models of human being was made. Author analyzed it in the following points of view: time of calculations and technical specifications