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Nguyen H, Vandewalle G, Mertens B, Collard JF, Hinsenkamp M, Verschaeve L, Feipel V, Magne I, Souques M, Beauvois V, Ledent M. Exposure assessment and cytogenetic biomonitoring study of workers occupationally exposed to extremely low-frequency magnetic fields. Bioelectromagnetics 2024; 45:260-280. [PMID: 38862415 DOI: 10.1002/bem.22506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 01/20/2024] [Accepted: 03/30/2024] [Indexed: 06/13/2024]
Abstract
Human cytogenetic biomonitoring (HCB) has long been used to evaluate the potential effects of work environments on the DNA integrity of workers. However, HCB studies on the genotoxic effects of occupational exposure to extremely low-frequency electromagnetic fields (ELF-MFs) were limited by the quality of the exposure assessment. More specifically, concerns were raised regarding the method of exposure assessment, the selection of exposure metrics, and the definition of exposure group. In this study, genotoxic effects of occupational exposure to ELF-MFs were assessed on peripheral blood lymphocytes of 88 workers from the electrical sector using the comet and cytokinesis-block micronucleus assay, considering workers' actual exposure over three consecutive days. Different methods were applied to define exposure groups. Overall, the summarized ELF-MF data indicated a low exposure level in the whole study population. It also showed that relying solely on job titles might misclassify 12 workers into exposure groups. We proposed combining hierarchical agglomerative clustering on personal exposure data and job titles to define exposure groups. The final results showed that occupational MF exposure did not significantly induce more genetic damage. Other factors such as age or past smoking rather than ELF-MF exposure could affect the cytogenetic test outcomes.
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Affiliation(s)
- Ha Nguyen
- Laboratoire de Recherche en Orthopédie Traumatologie, Université Libre de Bruxelles, Brussels, Belgium
- Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
| | - Giovani Vandewalle
- External Occupational Health Service for Prevention and Protection at Work, Mensura, Brussels, Belgium
| | - Birgit Mertens
- Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
| | - Jean-Francois Collard
- Laboratoire de Recherche en Orthopédie Traumatologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Maurice Hinsenkamp
- Laboratoire de Recherche en Orthopédie Traumatologie, Université Libre de Bruxelles, Brussels, Belgium
| | - Luc Verschaeve
- Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
| | - Veronique Feipel
- Laboratoire de Recherche en Orthopédie Traumatologie, Université Libre de Bruxelles, Brussels, Belgium
| | | | | | - Véronique Beauvois
- Applied and Computational Electromagnetics Unit, Université de Liège, Liège, Belgium
| | - Maryse Ledent
- Chemical and Physical Health Risks, Sciensano, Brussels, Belgium
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Stam R. New developments in cosmetic applications of electromagnetic fields: Client and occupational hazard assessment. Bioelectromagnetics 2024; 45:251-259. [PMID: 38533721 DOI: 10.1002/bem.22503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 11/14/2023] [Accepted: 02/15/2024] [Indexed: 03/28/2024]
Abstract
Energy-based devices are used to improve features of appearance for aesthetic reasons while avoiding more invasive methods. Examples of treatment targets are the reduction of wrinkles, sagging, unwanted skin lesions, body hair and excess fatty tissue, and the enhancement of muscle tissue. One treatment modality is the use of electromagnetic fields (EMF, 0‒300 GHz). The present work aims to give an up-to-date survey of cosmetic applications of EMF for professional use with an assessment of client and worker exposure and possible adverse effects. A systematic search was conducted for peer-reviewed articles (2007-2022), patents, premarket notifications, manufacturer data, and adverse effects reports. Five categories of cosmetic EMF device with increasing frequency were identified: sinusoid low frequency magnetic fields for lipolysis; pulsed low frequency magnetic fields for skin rejuvenation; pulsed low frequency magnetic fields for muscle building; radiofrequency EMF for lipolysis or skin rejuvenation; microwaves for hair removal or hyperhidrosis. In the vicinity of the last four device categories, there is a potential for exceeding the occupational exposure limits in the European Union EMF Directive, which could lead to nerve or muscle stimulation, burns or overheating. There are also potential hazards for clients or workers wearing active or passive medical devices. The severity of reported adverse effects increases with EMF frequency.
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Affiliation(s)
- Rianne Stam
- Centre for Sustainability, Environment and Health, National Institute for Public Health and the Environment, Bilthoven, The Netherlands
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3
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Schmid G, Schneeweiss P, Hirtl R, Jhala T, Samaras T. Numerical assessment of induced electric fields in a worker's hand with commonly used metallic implants under exposure to low frequency magnetic fields. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2024; 44:031507. [PMID: 39047759 DOI: 10.1088/1361-6498/ad66dc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2024] [Accepted: 07/24/2024] [Indexed: 07/27/2024]
Abstract
The European Union's Workers' Directive 2013/35/EU on the minimum health and safety requirements regarding the exposure of workers to electromagnetic fields specifies action levels (ALs) for external electric and magnetic fields, which should protect against induced tissue-internal electric field strengthEiabove the exposure limit values, the latter being defined in order to prevent tissue stimulation at low frequencies. However, although 2013/35/EU explicitly calls for the protection of 'workers at particular risk' (including workers with metallic implants), the AL specified in the Directive have been derived under the assumption that there are no metallic parts present inside the body. Therefore, in the present work, we analysed the situation of a worker's hand and forearm bearing metallic implants (Herbert screw and volar radius plate) used for osteosynthesis after the most common bone fractures of the hand/forearm, exposed to low frequency magnetic fields. The uniform exposure of the whole hand and forearm as well as the exposure to a specific and widely used device, a deactivator for single-use labels of acousto-magnetic electronic article surveillance systems, were considered based on numerical computations using a high-resolution anatomical hand and forearm model. The results obtained indicated that the maximum induced electric field strength averaged in a volume of 2 mm × 2 mm × 2 mm cube was higher in the presence of the metallic implants by a factor of up to 4.2 for bone tissue and 2.3 for soft tissue compared with the case without an implant. Hence, it is obvious that the local induced electric field strengths may be substantially increased by the implants. The extent of this increase, however, is highly dependent on the implant's position inside the body, the implant's geometry, and the field distribution and orientation with respect to the anatomical structure and the implant.
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Affiliation(s)
- Gernot Schmid
- Seibersdorf Laboratories, EMC & Optics, A-2444 Seibersdorf, Austria
- Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece
| | - Pia Schneeweiss
- Seibersdorf Laboratories, EMC & Optics, A-2444 Seibersdorf, Austria
| | - Rene Hirtl
- Seibersdorf Laboratories, EMC & Optics, A-2444 Seibersdorf, Austria
| | - Tobias Jhala
- Seibersdorf Laboratories, EMC & Optics, A-2444 Seibersdorf, Austria
- Department of Pediatric Surgery and Pediatric Urology, University Children's Hospital Tuebingen, D-72076 Tuebingen, Germany
| | - Theodoros Samaras
- Department of Physics, Aristotle University of Thessaloniki, GR-54124 Thessaloniki, Greece
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Nissi J, Kangasmaa O, Kataja J, Bouisset N, Laakso I. In vivoand dosimetric investigation on electrical vestibular stimulation with frequency- and amplitude-modulated currents. J Neural Eng 2024; 21:046038. [PMID: 39029488 DOI: 10.1088/1741-2552/ad658f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 07/19/2024] [Indexed: 07/21/2024]
Abstract
Objective. Normal function of the vestibular system can be disturbed using a noninvasive technique called electrical vestibular stimulation (EVS), which alters a person's sense of balance and causes false sensations of movement. EVS has been widely used to study the function of the vestibular system, and it has recently gained interest as a therapeutic tool to improve postural stability and help those suffering from vestibular dysfunction. Yet, understanding of how EVS stimulates the vestibular system, the current intensity needed to produce an effect and the frequencies at which it occurs have remained unclear.Approach. The effect of EVS on postural sway was examined in five participants using sinusoidal alternating current with time-varying amplitude from 0 to 1.5 mA and frequency from 0.1 to 10 Hz for three electrode configurations. Dosimetry of the current flow inside the head was conducted using anatomically realistic computational models created individually for each subject based on magnetic resonance imaging data. An estimate for the minimal field strength capable of affecting the vestibular system was calculated with the finite element method.Main results. Bipolar EVS at frequencies up to 10 Hz caused harmonic full-body swaying, and the frequency of the sway was the same as that of the stimulation current. The size of the sway was amplified by increasing the current intensity. Dosimetry modeling indicated that, for 0.2 mA current, the average electric field strength in the vestibular system was approximately 10-30 mV m-1, depending on the electrode montage. The size of the measured postural sway was proportional to the montage-specific electric field strength in the vestibular system.Significance. The results provide insight to EVS's working mechanisms and improve its potential as a tool to study the sense of balance.
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Affiliation(s)
- Janita Nissi
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Otto Kangasmaa
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Juhani Kataja
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Nicolas Bouisset
- Human Threshold Research Group, Lawson Health Research Institute, London, ON, Canada
- School of Kinesiology, Western University, London, ON, Canada
| | - Ilkka Laakso
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
- Aalto Neuroimaging, Aalto University, Espoo, Finland
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Vivarelli C, Censi F, Calcagnini G, Falsaperla R, Mattei E. Risk Assessment for Workers with Wearable Medical Devices Exposed to Electromagnetic Fields. HEALTH PHYSICS 2024; 127:269-275. [PMID: 38394479 DOI: 10.1097/hp.0000000000001798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
ABSTRACT The exponential diffusion of wearable medical devices (WMD) in recent years has involved people of all ages, including workers. Workers who use WMDs should be considered at a particular risk from electromagnetic fields, and in accordance with EU Directive 2013/35/EU, they require an individual risk assessment. Currently, there is no international standard that provides specific guidance on how to perform such a risk assessment. This paper focuses on the effects of electromagnetic fields on WMDs and does not consider the direct effects on human body tissues. It aims to offer practical recommendations to employers and/or health physicists for the risk assessment of workers with WMDs. Focusing on EU countries, we first describe the requirements outlined by the technical standard for the electromagnetic compatibility (EMC) of medical electrical equipment EN 60601-1-2. Then, some general guidelines on how to perform the risk assessment are provided. The assessment can be conducted by comparing the field values measured in the workplace with the immunity test levels specified in the technical standards of medical electrical equipment. If the measured values are lower than the immunity test levels indicated in the standard and the distance from the electromagnetic source is greater than the distance used by the manufacturer during the EMC (electromagnetic compatibility) tests (typically 30 cm), the risk for the worker may be considered acceptable. However, if the measured values exceed the immunity test levels or the distance criteria, a specific evaluation based on a case-by-case analysis is required.
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Affiliation(s)
| | - Federica Censi
- Italian National Institute of Health (ISS), Dept. of Cardiovascular, Endocrine-metabolic Diseases and Aging, Rome, Italy
| | - Giovanni Calcagnini
- Italian National Institute of Health (ISS), Dept. of Cardiovascular, Endocrine-metabolic Diseases and Aging, Rome, Italy
| | | | - Eugenio Mattei
- Italian National Institute of Health (ISS), Dept. of Cardiovascular, Endocrine-metabolic Diseases and Aging, Rome, Italy
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Validity of the 1984 Interim Guidelines on Airborne Ultrasound and Gaps in the Current Knowledge. HEALTH PHYSICS 2024; 127:326-347. [PMID: 38768315 DOI: 10.1097/hp.0000000000001800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
ABSTRACT Airborne ultrasound is used for various purposes both in industrial and public settings, as well as being produced as a by-product by a range of sources. The International Radiation Protection Association (IRPA) published interim guidelines on limiting human exposure to airborne ultrasound in 1984, based on the limited scientific evidence that was available at that time. In order to investigate whether research since 1984 requires the development of revised exposure guidelines we considered (a) within the context of ultrasound exposure the relevance to health of the biological endpoints/mechanisms listed in the IRPA guidelines, (b) the validity of the exposure limits, and (c) whether there are biological endpoints/mechanisms not covered in the guidelines. The analysis of the available evidence showed that the biological endpoints that form the basis of the guidelines are relevant to health and the guidelines provide limits of exposure based on the evidence that was available at the time. However, the IRPA limits and their associated dosimetry were based on limited evidence, which may not be considered as scientifically substantiated. Further, there is no substantiated evidence of biological endpoints/mechanisms not covered by the IRPA guidelines. These two observations could mean that IRPA's limits are too low or too high. Research since the IRPA guidelines has made some improvements in the knowledge base, but there are still significant data gaps that need to be resolved before a formal revision of the guidelines can be made by ICNIRP, including research needs related to health outcomes and improved dosimetry. This statement makes a number of recommendations for future research on airborne ultrasound.
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Silva LB, Beserra Melo CJ, Lisboa de Souza AG, de Oliveira LG. Ergonomics, Health, and Perceptions about Remote Domestic Workposts: Study in Areas of City of João Pessoa, Paraíba, Brazil. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2024; 21:941. [PMID: 39063517 PMCID: PMC11276999 DOI: 10.3390/ijerph21070941] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2024] [Revised: 07/12/2024] [Accepted: 07/16/2024] [Indexed: 07/28/2024]
Abstract
Home office (HO) stands out as one of the most promising and popular forms of teleworking, especially after the COVID-19 pandemic. Therefore, many companies want to implement or maintain this working method, given its numerous advantages. However, there are adverse effects that are mainly related to physical and mental health. This article presents ergonomic analyses of HOs in neighborhoods considered heat islands. Temperature levels, extreme low-frequency non-ionizing radiation (ELF-NIR), illuminance, physical layout characteristics, and physiological parameters of teleworkers were measured. The results reveal that 92% of these professionals work 6 to 8 h daily with an ambient temperature between 25 and 30 °C, illumination levels in the range 11.20-290 Lux, and ELF-NIR > 0.4 µT. The majority of teleworkers are overweight (BMI > 24.9), and some of them have blood pressure higher than average values (129 mmHg for systolic and 84 mmHg for diastolic) in addition to a reduction in the number of red blood cells and hematocrits. Symptoms such as burning sensation, dryness, tired eyes, redness, itching, and photophobia (light sensitivity) show a 68.95% similarity. These HOs do not meet the required ergonomic and health standards.
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Affiliation(s)
- Luiz Bueno Silva
- Department of Production Engineering, Federal University of Paraíba, João Pessoa 58051-970, Brazil; (C.J.B.M.); (A.G.L.d.S.); (L.G.d.O.)
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Yang C, Lu M. Computational analysis of electromagnetic field exposure in passengers near high- current contact wire environments. RADIATION PROTECTION DOSIMETRY 2024:ncae162. [PMID: 39016042 DOI: 10.1093/rpd/ncae162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 04/27/2024] [Accepted: 06/29/2024] [Indexed: 07/18/2024]
Abstract
The electromagnetic environment of a railway station is composed of electrical, magnetic, and electromagnetic fields, which are generated by various sources such as traction current, voltage, pantograph-catenary arc, locomotive braking, wheel-rail rolling arc, and communication systems. However, there is public growing concern among the public about the potential negative human health effects of this electromagnetic environment. To analyze the distribution of electromagnetic fields in human tissues, electromagnetic simulation software is used to create a model that includes six track contact wires and four waiting passengers on three platforms. This model is used to analyze the magnetic field environment created by high currents in the contact wires of a multi-track high-speed railway station. By varying the loads on different contact wires, the distribution of electric field and magnetic flux density within human tissues of waiting passengers on different platforms is studied using this model. When the track is unoccupied, the calculation results show that the maximum values of the electric field and magnetic flux density of the passenger's human body tissue at the blind way on the platform and 1 m of the blind way are 17.6 mV m-1 and 52.7 μT, respectively. These values increase by 9.28 mV m-1 and 16.4 μT compared to when the track is occupied. When more contact wires are loaded with currents, the electric field mode and magnetic flux density mode of human tissues increase at the same position on the platform. Specifically, when the contact wires of six tracks are loaded with current at the same time, the maximum values of the electric field mode and magnetic flux density mode of the waiting passengers' human tissues at the blind way on different platforms are 29.6 mV m-1 and 88.1 μT, respectively. These maximum values are lower than the public electromagnetic exposure limits that are designated by the International Commission on Non-Ionizing Radiation Protection guidelines. The research results demonstrate that the magnetic field environment generated by the current in the contact wires of a railway station with six tracks does not pose a health risk to human tissues of passengers waiting at the blind way and 1 m of the blind way on the platform. These findings can provide valuable data reference for the formulation of relevant standards for the design of electrified rail transit, as well as the suppression of electromagnetic interference and protection of human bioelectromagnetism.
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Affiliation(s)
- Changqiong Yang
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Gansu Province, Lanzhou 730070, China
| | - Mai Lu
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Gansu Province, Lanzhou 730070, China
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Worel N, Mišík M, Kundi M, Ferk F, Hutter HP, Nersesyan A, Wultsch G, Krupitza G, Knasmueller S. Impact of high (1950 MHz) and extremely low (50 Hz) frequency electromagnetic fields on DNA damage caused by occupationally relevant exposures in human derived cell lines. Toxicol In Vitro 2024; 100:105902. [PMID: 39025159 DOI: 10.1016/j.tiv.2024.105902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 06/27/2024] [Accepted: 07/15/2024] [Indexed: 07/20/2024]
Abstract
Epidemiological studies indicate that electromagnetic fields (EMF) are associated with cancer in humans. Exposure to mobile phone specific high frequency fields (HF-EMF) may lead to increased glioma risks, while low frequency radiation (LF-EMF) is associated with childhood leukemia. We studied the impact of HF-EMF (1950 MHz, UMTS signal) on DNA stability in an astrocytoma cell line (1321N1), and the effect of LF-EMF (50 Hz) in human derived lymphoma (Jurkat) cells. To find out if these fields affect chemically induced DNA damage, co-exposure experiments were performed. The cells were exposed to HF-EMF or LF-EMF and treated simultaneously and sequentially with mutagens. The compounds cause DNA damage via different molecular mechanisms, i.e. pyrimidine dimers which are characteristic for UV light (4-nitroquinoline 1-oxide, 4NQO), bulky base adducts (benzo[a]pyrene diolepoxide, BPDE), DNA-DNA and DNA-protein cross links and oxidative damage (NiCl2, CrO3). DNA damage was measured in single cell gel electrophoresis (comet) assays. We found a moderate reduction of basal and 4NQO-induced DNA damage in the astrocytoma line, but no significant alterations of chemically induced DNA migration by the HF and LF fields under all other experimental series. The biological consequences of the moderate reduction remain unclear, but our findings indicate that acute mobile phone and power line specific EMF exposures do not enhance genotoxic effects caused by occupationally relevant chemical exposures.
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Affiliation(s)
- Nadine Worel
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Miroslav Mišík
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Michael Kundi
- Center for Public Health, Department of Environmental Health, Medical University of Vienna, Vienna, Austria
| | - Franziska Ferk
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | - Hans-Peter Hutter
- Center for Public Health, Department of Environmental Health, Medical University of Vienna, Vienna, Austria
| | - Armen Nersesyan
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria
| | | | - Georg Krupitza
- Department of Pathology, Medical University of Vienna, A-1090 Vienna, Austria
| | - Siegfried Knasmueller
- Center for Cancer Research, Medical University of Vienna, Borschkegasse 8a, A 1090 Vienna, Austria.
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Camera F, Merla C, De Santis V. Comparison of Transcranial Magnetic Stimulation Dosimetry between Structured and Unstructured Grids Using Different Solvers. Bioengineering (Basel) 2024; 11:712. [PMID: 39061794 PMCID: PMC11273852 DOI: 10.3390/bioengineering11070712] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2024] [Revised: 07/05/2024] [Accepted: 07/10/2024] [Indexed: 07/28/2024] Open
Abstract
In recent years, the interest in transcranial magnetic stimulation (TMS) has surged, necessitating deeper understanding, development, and use of low-frequency (LF) numerical dosimetry for TMS studies. While various ad hoc dosimetric models exist, commercial software tools like SimNIBS v4.0 and Sim4Life v7.2.4 are preferred for their user-friendliness and versatility. SimNIBS utilizes unstructured tetrahedral mesh models, while Sim4Life employs voxel-based models on a structured grid, both evaluating induced electric fields using the finite element method (FEM) with different numerical solvers. Past studies primarily focused on uniform exposures and voxelized models, lacking realism. Our study compares these LF solvers across simplified and realistic anatomical models to assess their accuracy in evaluating induced electric fields. We examined three scenarios: a single-shell sphere, a sphere with an orthogonal slab, and a MRI-derived head model. The comparison revealed small discrepancies in induced electric fields, mainly in regions of low field intensity. Overall, the differences were contained (below 2% for spherical models and below 12% for the head model), showcasing the potential of computational tools in advancing exposure assessment required for TMS protocols in different bio-medical applications.
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Affiliation(s)
- Francesca Camera
- Division of Biotechnologies, Italian National Agency for Energy, New Technologies and Sustainable Economic Development (ENEA), 00123 Rome, Italy;
| | - Caterina Merla
- Division of Biotechnologies, Italian National Agency for Energy, New Technologies and Sustainable Economic Development (ENEA), 00123 Rome, Italy;
| | - Valerio De Santis
- Department of Industrial and Information Engineering and Economics, University of L’Aquila, 67100 L’Aquila, Italy;
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Dong X, Qian Y, Lu M. Electromagnetic Exposure Levels of Electric Vehicle Drive Motors to Passenger Wearing Cardiac Pacemakers. SENSORS (BASEL, SWITZERLAND) 2024; 24:4395. [PMID: 39001174 PMCID: PMC11244417 DOI: 10.3390/s24134395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Revised: 07/04/2024] [Accepted: 07/05/2024] [Indexed: 07/16/2024]
Abstract
The number of individuals wearing cardiac pacemakers is gradually increasing as the population ages and cardiovascular disease becomes highly prevalent. The safety of pacemaker wearers is of significant concern because they must ensure that the device properly functions in various life scenarios. Electric vehicles have become one of the most frequently used travel tools due to the gradual promotion of low-carbon travel policies in various countries. The electromagnetic environment inside the vehicle is highly complex during driving due to the integration of numerous high-power electrical devices inside the vehicle. In order to ensure the safety of this group, the paper takes passengers wearing cardiac pacemakers as the object and the electric vehicle drive motors as the exposure source. Calculation models, with the vehicle body, human body, heart, and cardiac pacemaker, are built. The induced electric field, specific absorption rate, and temperature changes in the passenger's body and heart are calculated by using the finite element method. Results show that the maximum value of the induced electric field of the passenger occurs at the ankle of the body, which is 60.3 mV/m. The value of the induced electric field of the heart is greater than that of the human trunk, and the maximum value (283 mV/m) is around the pacemaker electrode. The maximum specific absorption rate of the human body is 1.08 × 10-6 W/kg, and that of heart positioned near the electrode is 2.76 × 10-5 W/kg. In addition, the maximum temperature increases of the human torso, heart, and pacemaker are 0.16 × 10-5 °C, 0.4 × 10-6 °C, and 0.44 × 10-6 °C within 30 min, respectively. Accordingly, the induced electric field, specific absorption rate, and temperature rise in the human body and heart are less than the safety limits specified in the ICNIRP. The electric field intensity at the pacemaker electrode and the temperature rise of the pacemaker meet the requirements of the medical device standards of ICNIRP and ISO 14708-2. Consequently, the electromagnetic radiation from the motor operation in the electric vehicle does not pose a safety risk to the health of passengers wearing cardiac pacemakers in this paper. This study also contributes to advancing research on the electromagnetic environment of electric vehicles and provides guidance for ensuring the safe travel of individuals wearing cardiac pacemakers.
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Affiliation(s)
- Xuwei Dong
- Key Laboratory of Opto-Electronic Technology and Intelligent Control of the Ministry of Education, Lanzhou Jiaotong University, Lanzhou 730070, China; (Y.Q.); (M.L.)
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12
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Nieminen V, Martikainen MV, Kalliomäki S, Virén T, Seppälä J, Juutilainen J, Naarala J, Luukkonen J. 50 Hz magnetic field influences caspase-3 activity and cell cycle distribution in ionizing radiation exposed SH-SY5Y neuroblastoma cells. Int J Radiat Biol 2024; 100:1183-1192. [PMID: 38924721 DOI: 10.1080/09553002.2024.2369105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/29/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024]
Abstract
PURPOSE Earlier evidence suggests that extremely low frequency magnetic fields (ELF MFs) can modify the effects of carcinogenic agents. However, the studies conducted so far with ionizing radiation as the co-exposure agent are sparse and have provided inconclusive results. We investigated whether 50 Hz MFs alone, or in combination with ionizing radiation alter cell biological variables relevant to cancer and the biological effects of ionizing radiation. MATERIALS AND METHODS Human SH-SY5Y neuroblastoma cells were sham exposed or exposed to 100 or 500 µT MF for 24 h either before or after ionizing radiation exposure (0, 0.4 or 2 Gy). After the exposures, cells were assayed for viability, clonogenicity, reactive oxygen species, caspase-3 activity, and cell cycle distribution. Cell cycle distribution was assayed with propidium iodide staining followed by flow cytometry analysis and ROS levels were assayed together with cell viability by double staining with DeepRed and Sytox Blue followed by flow cytometry analysis. RESULTS Increased caspase-3 activity was observed in cells exposed to 500 µT MF before or after ionizing radiation. Furthermore, exposure to the 500 µT MF after the ionizing radiation decreased the percentage of cells in S-phase. No changes in the ROS levels, clonogenicity, or viability of the cells were observed in the MF exposed groups compared to the corresponding sham exposed groups, and no MF effects were observed in cells exposed at 100 µT. CONCLUSIONS Only the 500 µT magnetic flux density affected SH-SY5Y cells significantly. The effects were small but may nevertheless help to understand how MFs modify the effects of ionizing radiation. The increase in caspase-3 activity may not reflect effects on apoptosis, as no changes were observed in the subG1 phase of the cell cycle. In contrast to some earlier findings, 50 Hz MF exposure after ionizing radiation was not less effective than MF treatment given prior to ionizing radiation.
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Affiliation(s)
- Valtteri Nieminen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Maria-Viola Martikainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Saija Kalliomäki
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Tuomas Virén
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Jan Seppälä
- Center of Oncology, Kuopio University Hospital, Kuopio, Finland
| | - Jukka Juutilainen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jonne Naarala
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
| | - Jukka Luukkonen
- Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, Finland
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13
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Tachibana M, Inada T, Kimura H, Ito M, Kuwatsuka Y, Kinoshita F, Mori D, Ohno K. Extremely Low Frequency, Extremely Low Magnetic Environment for depression: An open-label trial. Asian J Psychiatr 2024; 96:104036. [PMID: 38555753 DOI: 10.1016/j.ajp.2024.104036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 03/20/2024] [Accepted: 03/25/2024] [Indexed: 04/02/2024]
Abstract
Mitochondrial dysfunction has been suggested to play a role in depression pathogenesis. This clinical trial (jRCTs042220011) was conducted to evaluate whether depression symptoms could be alleviated by an Extremely Low Frequency, Extremely Low Magnetic Environment (ELF-ELME), which has been found in basic research studies to enhance mitochondrial membrane potential. Participants were exposed to the ELF-ELME via a head-mounted magnetic field device (10 μTesla, 4 ms, 1-8 Hz/8 s) worn for 2 h per day for 8 consecutive weeks. Four male patients with treatment-resistant depression were enrolled. Significant reductions from baseline in the average total Montgomery-Åsberg Depression Rating Scale (MADRS) score were observed at 4, 6, and 8 weeks. ELF-ELME appears to ameliorate depressive symptoms in patients with major depressive disorder safely and effectively, suggesting that it could be used as an alternative treatment for depressive patients who do not prefer to take antidepressants and in combination with antidepressant therapy for patients who only partially respond to pharmacotherapy.
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Affiliation(s)
- Masako Tachibana
- Department of Psychiatry, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Toshiya Inada
- Department of Psychiatry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan.
| | - Hiroki Kimura
- Department of Psychiatry, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Mikako Ito
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Yachiyo Kuwatsuka
- Department of Advanced Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Fumie Kinoshita
- Department of Advanced Medicine, Nagoya University Hospital, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Daisuke Mori
- Brain and Mind Research Center, Nagoya University, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
| | - Kinji Ohno
- Division of Neurogenetics, Center for Neurological Diseases and Cancer, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya-shi, Aichi 466-8550, Japan
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14
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Kanemaki M, Shimizu HO, Inujima H, Miyake T, Shimizu K. Quantitative analyses of RBC movement in whole blood exposed to DC and ELF electric field. Bioelectromagnetics 2024; 45:159-170. [PMID: 38081752 DOI: 10.1002/bem.22493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Revised: 08/11/2023] [Accepted: 11/02/2023] [Indexed: 04/17/2024]
Abstract
For the study of biological effects of direct current (DC) and extremely low frequency (ELF) electric fields, we have quantitatively analyzed red blood cell (RBC) movement in whole blood. Considering the inhomogeneous distribution of electric fields in vivo, five different electric field distributions were generated under a microscope. For theoretical analyses, we assumed electrophoresis and dielectrophoresis as basic motive forces and obtained the spatial distribution of blood cell velocity. The RBC velocity was measured using video image analysis. The spatial dependence of the velocity showed good agreement with that predicted by theoretical analysis. This result suggests the validity of the theoretical model based on electrophoresis and dielectrophoresis for the study of ELF electric field exposure to inhomogeneous animal and human bodies. Next, using the same measurement system, we attempted to find the electric field strength at which these effects occur. The threshold values were found to be 0.40 and 1.6 kV/m, respectively, for DC and AC electric field exposures. Furthermore, we investigated the reproducibility of the field effects in more realistic conditions of human exposure. The RBCs in microchannels were exposed to the electric field generated in capacitive coupling using electrodes separated by an air gap. Even in the new condition, similar effects were observed, which also verified the validity of the analysis described above. These results will provide useful information for the safety assessment of field exposure and for the future biomedical applications of electric fields to manipulate RBCs in vivo.
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Affiliation(s)
- Miki Kanemaki
- Graduate School of Information, Production and Systems, Waseda University, Kitakyushu, Japan
| | - Hisae O Shimizu
- Graduate School of Health Science, Hokkaido University of Science, Sapporo, Japan
| | - Hiroshi Inujima
- Graduate School of Information, Production and Systems, Waseda University, Kitakyushu, Japan
| | - Takeo Miyake
- Graduate School of Information, Production and Systems, Waseda University, Kitakyushu, Japan
| | - Koichi Shimizu
- School of Optoelectronic Engineering, Xidian University, Xi'an, China
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15
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Legros A, Nissi J, Laakso I, Duprez J, Kavet R, Modolo J. Thresholds and mechanisms of human magnetophosphene perception induced by low frequency sinusoidal magnetic fields. Brain Stimul 2024; 17:668-675. [PMID: 38740182 DOI: 10.1016/j.brs.2024.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2023] [Revised: 05/07/2024] [Accepted: 05/07/2024] [Indexed: 05/16/2024] Open
Abstract
BACKGROUND Virtually everyone is exposed to power-frequency MF (50/60 Hz), inducing in our body electric fields and currents, potentially modulating brain function. MF-induced electric fields within the central nervous system can generate flickering visual perceptions (magnetophosphenes), which form the basis of international MF exposure guidelines and recommendations protecting workers and the general public. However, magnetophosphene perception thresholds were estimated 40 years ago in a small, unreplicated study with significant uncertainties and leaving open the question of the involved interaction site. METHODS We used a stimulation modality termed transcranial alternating magnetic stimulation (tAMS), delivering in situ sinusoidal electric fields comparable to transcranial alternating current stimulation (tACS). Magnetophosphene perception was quantified in 81 volunteers exposed to MF (eye or occipital exposure) between 0 and 50 mT at frequencies of 20, 50, 60 and 100 Hz. RESULTS Reliable magnetophosphene perception was induced with tAMS without any scalp sensation, a major advantage as compared to tACS. Frequency-dependent thresholds were quantified using binary logistic regressions hence allowing to establish condition dependent probabilities of perception. Results support an interaction between induced current density and retinal rod cells. CONCLUSION Beyond fundamental and immediate implications for international safety guidelines, and for identifying the interaction site underlying phosphene perception (ubiquitous in tACS experiments), our results support exploring the potential of tAMS for the differential diagnosis of retinal disorders and neuromodulation therapy.
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Affiliation(s)
- Alexandre Legros
- Human Threshold Research Group, Lawson Health Research Institute, London, ON, Canada; Departments of Medical Biophysics and Medical Imaging Western University, London, ON, Canada; School of Kinesiology, Western University, London, ON, Canada; EuroMov Digital Health in Motion, University of Montpellier and IMT Mines Ales, Montpellier, France.
| | - Janita Nissi
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Ilkka Laakso
- Department of Electrical Engineering and Automation, Aalto University, Espoo, Finland
| | - Joan Duprez
- Univ Rennes, INSERM, LTSI - U1099, F-35000, France
| | | | - Julien Modolo
- Human Threshold Research Group, Lawson Health Research Institute, London, ON, Canada; Univ Rennes, INSERM, LTSI - U1099, F-35000, France
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16
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Tian R, Li WX, Lu M, Yu L, Zhang JQ. Research on the influence of power frequency magnetic field of pantograph on pacemaker wearers' health in high-speed EMU. RADIATION PROTECTION DOSIMETRY 2024; 200:588-597. [PMID: 38486443 DOI: 10.1093/rpd/ncae057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 01/16/2024] [Accepted: 02/26/2024] [Indexed: 04/23/2024]
Abstract
When the popular means of transportation-high-speed trains meet the increasing rate of pacemaker implantation year by year, the research on the magnetic field environment on the health of pacemaker wearers in the carriage becomes an urgent problem. In this work, models of an electric multiple unit carriage with a pantograph as well as passengers with pacemakers were built by using COMSOL Multiphysics software. The B, Ein and Jin of human heart and other tissues, and the induced voltage (Vin) at the pacemaker electrode were calculated under the pantograph operating condition, so as to assess the effect of its magnetic field on the health of pacemaker wearers. The results showed that Bmax in the carriage without passengers is 121.246 μT, occurs near the window. In the carriage, the Bmax, Ein max and Jin max of heart and body, Vin at the pacemaker electrode of the passenger next to the window are greater than that in the middle of the carriage. The Bmax, Ein max and Jin max of passengers' heart are 11.301μT, 1.613 mV/m and 139.030 μA/m2, respectively. The Bmax, Ein max and Jin max of passengers' body are 12.597μT, 0.788 mV/m and 75.299 μA/m2, respectively. The maximum value of Vin at the tip of the pacemaker electrode of the passengers' is 0.048 mV. The Bmax, Ein max in all tissues of passengers are much smaller than the basic limits of electromagnetic exposure to the public set by the International Commission on Non-Ionizing Radiation. Vin at the electrode tip of passengers' pacemakers are less than the perception sensitivity set by the International Organization for Standardization. This work illustrated that the magnetic field generated by the pantograph is within the recognized accepted limits for passengers with pacemakers, but we still recommended that passengers wearing pacemakers should stay as far away from windows as possible.
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Affiliation(s)
- Rui Tian
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Lanzhou 730070, China
| | - Wei-Xuan Li
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Lanzhou 730070, China
| | - Mai Lu
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Lanzhou 730070, China
| | - Li Yu
- China Railway First Survey and Design Institute Group Co., Ltd, No. 131, Hezheng Road, Chengguan District, Lanzhou 730030, Gansu Province, China
| | - Jia-Qi Zhang
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, No. 88 Anning West Road, Anning District, Lanzhou 730070, China
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17
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Mukherjee D, Rainu SK, Singh N, Mallick D. A Miniaturized, Low-Frequency Magnetoelectric Wireless Power Transfer System for Powering Biomedical Implants. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2024; 18:438-450. [PMID: 37999967 DOI: 10.1109/tbcas.2023.3336598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2023]
Abstract
This work experimentally demonstrates the operation of a miniaturized magnetoelectric (ME) wireless power transfer (WPT) system by incorporating a ME transducer and a suitable interface power management circuit (PMC) for potentially powering implantable medical devices (IMD) wirelessly. A ME heterostructure is micromachined to obtain desired device dimensions of 3.5 × 5 mm 2 and to restrict the operating frequency at a clinically approved frequency of 50 kHz. The proposed work also aims to address the trade-off between the device miniaturization, power attenuation and limiting the specific absorption rate (SAR) in the human tissue. By limiting the operating frequency to 50 kHz, the SAR is reduced to less than 1 μW/kg. The fabricated device is characterized with low-intensity AC magnetic field up to 40 μT without using any DC bias, resulting in 0.4 V output voltage and 6.6 μW power across 8 k Ω load. Alignment misorientation between the Tx and Rx is studied for in-plane and out-of-plane angular rotations to confirm the device's reliability against angular misalignment. By eliminating the bulky biasing magnets, the proposed device achieves a significant size reduction compared to the previously reported works. In addition, a self-powered interface PMC is incorporated with the ME system. The PMC generates 3.5 V regulated DC voltage from the input AC voltage range 0.7 V to 3.3 V. The PMC is fabricated on a 2-layered PCB and the over all ME WPT system consumes 12 × 12 mm 2 area. The overall PMC has intrinsic current consumption less than 550 nA with peak power conversion efficiency higher than 85 %. The in vitro cytotoxicity analysis in the human hepatic cell line WRL-68 confirmed the biocompatibility of the Parylene-C encapsulated ME device for up to 7 days, suggesting its potential use in implantable electronic devices for biomedical and clinical applications.
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18
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Özüpak Y. Analysis and experimental verification of efficiency parameters affecting inductively coupled wireless power transfer systems. Heliyon 2024; 10:e27420. [PMID: 38495211 PMCID: PMC10940927 DOI: 10.1016/j.heliyon.2024.e27420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 02/28/2024] [Accepted: 02/28/2024] [Indexed: 03/19/2024] Open
Abstract
Wireless power transfer (WPT) provides a safe and independent transfer of energy without the constraints of cables. The most suitable method for wireless charging of Electric Vehicles (EVs) is magnetic resonance coupling, which transfers energy in the near field. In this study, the effect of quality factor on the wireless charging system of an EV is investigated. After determining 85 kHz frequency, 20 kW power and 150 mm inter-coil distance, the design of the WPT system was realised according to the quality factor. It was observed that the quality factor affects the efficiency, critical air gap and voltage stress on capacitors. As the quality factor increases, the critical air gap increases and longer distances can be transmitted efficiently. However, as this factor increases, the voltage stress on the capacitors also increases. In this study, the critical air gap was determined according to the quality factor. Although high quality factor increases efficiency at high air gaps, it decreases efficiency in applications where air gaps are close. In fact, increasing the quality factor by increasing the inductance means increasing the internal resistance and this has been observed to reduce the maximum efficiency. In this study, the effects of Q factor on transmission power and transmission efficiency are investigated through experimental study and simulation.
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Affiliation(s)
- Yıldırım Özüpak
- Dicle University, Silvan Vocational School, Electrical Department, Diyarbakır, Turkey
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19
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Mou W, Lu M. Safety assessment of wireless chargers for electric vehicles considering thermal characteristics. RADIATION PROTECTION DOSIMETRY 2024; 200:187-200. [PMID: 38038046 DOI: 10.1093/rpd/ncad288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/28/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023]
Abstract
This study employs the transient finite element method and electromagnetic heat transfer theory to assess the heating generated by high-power wireless chargers during electric vehicle charging. The analysis includes simulating and analyzing the temperature distribution of two different types of shielding plates of the wireless charger and the specific absorption rate (SAR) and head temperature rise of both adults and children in close proximity to the charger. Simulation results show that the maximum temperature rise of the copper shielding plate is 16°C lower than that of the aluminum shielding plate after charging for 1 h. This temperature increase does not affect the chassis' s equipment. Regarding human safety, the induced electric field strength and SAR values in the child's head tissue are higher than those in the adult, meeting the International Commission on Non-Ionizing Radiation Protection (ICNIRP) limits. When the initial temperature is set to 37°C, the temperature rise in the heads of both adults and children is approximately equal after 1 h of charging, reaching a maximum temperature rise of 0.21 and 0.23°C, respectively. These values remain below the thermal limit of ICNIRP (2°C for Type 2 tissues). The findings indicate that the copper shielding plate can provide both electromagnetic shielding and heat dissipation functions, and the electromagnetic exposure absorbed by the human body and head temperature rise within safe ranges.
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Affiliation(s)
- Wenting Mou
- Institute of Railway Technology, Lanzhou Jiaotong University, Lanzhou 730070, China
| | - Mai Lu
- Key Laboratory of Opto-Electronic Technology and Intelligent Control, Ministry of Education, Lanzhou Jiaotong University, Lanzhou 730070, China
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20
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Zilberti L, Arduino A, Torchio R, Zanovello U, Baruffaldi F, Sanchez-Lopez H, Bettini P, Alotto P, Chiampi M, Bottauscio O. Orthopedic implants affect the electric field induced by switching gradients in MRI. Magn Reson Med 2024; 91:398-412. [PMID: 37772634 DOI: 10.1002/mrm.29861] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 08/18/2023] [Accepted: 08/20/2023] [Indexed: 09/30/2023]
Abstract
PURPOSE To investigate whether the risk of peripheral nerve stimulation increases in the presence of bulky metallic prostheses implanted in a patient's body. METHODS A computational tool was used to calculate the electric field (E-field) induced in a realistic human model due to the action of gradient fields. The calculations were performed both on the original version of the anatomical model and on a version modified through "virtual surgery" to incorporate knee, hip, and shoulder prostheses. Five exam positions within a body gradient coil and one position using a head gradient coil were simulated, subjecting the human model to the readout gradient from an EPI sequence. The induced E-field in models with and without prostheses was compared, focusing on the nerves and all other tissues (both including and excluding the bones from the analysis). RESULTS In the nerves, the most pronounced increase in the E-field (+24%) was observed around the knee implant during an abdominal MRI (Y axis readout). When extending the analysis to encompass all tissues (excluding bones), the greatest amplification (+360%) occurred around the knee implant during pelvic MRI (Z axis readout). Notable increases in E-field peaks were also identified around the shoulder and hip implants in multiple scenarios. CONCLUSION Based on the presented results, further investigations aimed at quantifying the threshold of nerve stimulation in the presence of bulky implants are desirable.
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Affiliation(s)
- Luca Zilberti
- Istituto Nazionale di Ricerca Metrologica (INRIM), Torino, Italy
| | | | - Riccardo Torchio
- Department of Industrial Engineering, Università degli Studi di Padova, Padova, Italy
| | | | | | - Hector Sanchez-Lopez
- Research Center for Medical Artificial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Paolo Bettini
- Department of Industrial Engineering, Università degli Studi di Padova, Padova, Italy
| | - Piergiorgio Alotto
- Department of Industrial Engineering, Università degli Studi di Padova, Padova, Italy
| | - Mario Chiampi
- Istituto Nazionale di Ricerca Metrologica (INRIM), Torino, Italy
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21
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Zhao Z, Yang X, Li Y, Luo C. Effect of outer spherical shell opening structure on the sensitivity of double spherical shell electric field sensor. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:015008. [PMID: 38284813 DOI: 10.1063/5.0167489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 12/30/2023] [Indexed: 01/30/2024]
Abstract
A double spherical shell (DSS) electric field sensor based on charge sensing has characteristics of small size and simple fabrication, which are appropriate for measuring complex electric field environments, but the sensitivity is low. To improve the sensitivity of the DSS electric field sensor, we theoretically analyze the effect of the diameter of the outer spherical shell opening on the sensitivity of the sensor. The sensors with outer spherical shell apertures of 2, 4, and 6 mm are designed and manufactured, and the sensor's sensitivity, linearity, hysteresis, and repeatability are tested. The relative error of the sensor is evaluated by measuring the rotational characteristics of the sensor. The experimental results show that the sensor sensitivity increases with the increase in hole diameter, while the sensor has good linearity, hysteresis, and repeatability after opening the hole. The rotational characteristics experiments' results show that the sensors' relative errors with different apertures are 18, 23, and 31%, respectively. The DSS open-hole structure is more suitable for electric field measurements than the conventional flat plate structure.
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Affiliation(s)
- Zhengang Zhao
- Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China
- Yunnan Key Laboratory of Computer Technologies Application, Kunming 650500, China
| | - Xuanyi Yang
- Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China
| | - Yitan Li
- Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China
| | - Chuan Luo
- Faculty of Information Engineering and Automation, Kunming University of Science and Technology, Kunming 650500, China
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22
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Tan L, Li G, Xie Q, Xiang Y, Luo B. Study on the safety assessment and protection design of human exposure to low-frequency magnetic fields in electric vehicles. RADIATION PROTECTION DOSIMETRY 2023; 200:60-74. [PMID: 37819666 DOI: 10.1093/rpd/ncad269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 08/14/2023] [Accepted: 09/19/2023] [Indexed: 10/13/2023]
Abstract
As the power performance of electric vehicles continues to improve, the human body may be exposed to electromagnetic threats in the cabin. This study tested an electric vehicle to analyze the low-frequency magnetic field distribution in the cabin and to assess the safety of human low-frequency magnetic field exposure. A simulation analysis of human electromagnetic exposure was carried out to obtain the magnetic flux density, induced electric field strength and induced current density, and the test results were much lower than the limits specified in GB8702-2014 and the International Commission on Non-Ionizing Radiation Protection, and the relative error between the simulation results and the test results was <15%. This paper investigates the frequency, driving current, vehicle body material and cable layout to explore the law of human body induced electromagnetic field changing with power cable current, and provides theoretical reference for the design of human body low-frequency magnetic field protection.
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Affiliation(s)
- LiGang Tan
- State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Ministry of Education, Hunan University, Changsha 410082, China
| | - GaoLei Li
- State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Ministry of Education, Hunan University, Changsha 410082, China
| | - QiaoLing Xie
- Shengjing Hospital of China Medical University, PRC National Health and Safety Commission (NHSC), Shenyang 110134, China
| | - Yunxiu Xiang
- Pan Asia Technical Automotive Center Co., Ltd, PRC Ministry of Transport (MOT), Shanghai 201201, China
| | - Baojun Luo
- State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Ministry of Education, Hunan University, Changsha 410082, China
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23
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Sato Y, Taki M, Kojimahara N. Association Between the Use of Induction Heating Cookers and Delivery Outcomes in Pregnant Women: An Internet-Based Cohort Study. ENVIRONMENTAL HEALTH INSIGHTS 2023; 17:11786302231211114. [PMID: 38021105 PMCID: PMC10655672 DOI: 10.1177/11786302231211114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 10/04/2023] [Indexed: 12/01/2023]
Abstract
The number of devices that generate intermediate-frequency electromagnetic fields (IF-EMFs) in the living environment has been increasing. As the public has vague concerns about new devices, it is necessary to clarify the safety of IF-EMFs. Therefore, the present study aimed to examine the possible health effects of IF-EMFs by clarifying the relationship between the use of induction heating (IH) cookers and delivery outcomes. The study participants were pregnant women over the age of 20 years who were registered in panels with an Internet research firm. A total of 8920 pregnant women participated in the baseline survey. Of those who responded to the follow-up survey, 5022 who had a singleton birth were included in the analysis. We then examined the relationship between the use of IH cookers and gestational week at delivery (<37th/⩾37th week) or birth weight (<2500/⩾2500 g) using logistic regression models. No association was found between the use of IH cookers and birth weight, but weak associations were found between the use of stationary- and tabletop-type IH cookers and gestational week at delivery. After all considerations, we determined that the observed increased odds ratio did not indicate an increased risk of premature birth.
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Affiliation(s)
- Yasuto Sato
- Graduate School of Public Health, Shizuoka Graduate University of Public health, Shizuoka, Japan
| | - Masao Taki
- Graduate School of Systems Design, Tokyo Metropolitan University, Tokyo, Japan
| | - Noriko Kojimahara
- Graduate School of Public Health, Shizuoka Graduate University of Public health, Shizuoka, Japan
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24
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Okabe N, Hovanesyan M, Azarapetian S, Dai W, Weisinger B, Parabucki A, Balter SR, Shohami E, Segal Y, Carmichael ST. Theta Frequency Electromagnetic Stimulation Enhances Functional Recovery After Stroke. Transl Stroke Res 2023:10.1007/s12975-023-01202-z. [PMID: 37962771 DOI: 10.1007/s12975-023-01202-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/14/2023] [Accepted: 10/13/2023] [Indexed: 11/15/2023]
Abstract
Extremely low-frequency, low-intensity electromagnetic field (ELF-EMF) therapy is a non-invasive brain stimulation method that can modulate neuroprotection and neuroplasticity. ELF-EMF was recently shown to enhance recovery in human stroke in a small pilot clinical trial (NCT04039178). ELF-EMFs encompass a wide range of frequencies, typically ranging from 1 to 100 Hz, and their effects can vary depending on the specific frequency employed. However, whether and to what extent the effectiveness of ELF-EMFs depends on the frequency remains unclear. In the present study, we aimed to assess the efficacy of different frequency-intensity protocols of ELF-EMF in promoting functional recovery in a mouse cortical stroke model with treatment initiated 4 days after the stroke, employing a series of motor behavior tests. Our findings demonstrate that a theta-frequency ELF-EMF (5 Hz) effectively enhances functional recovery in a reach-to-grasp task, whereas neither gamma-frequency (40 Hz) nor combination frequency (5-16-40 Hz) ELF-EMFs induce a significant effect. Importantly, our histological analysis reveals that none of the ELF-EMF protocols employed in our study affect infarct volume, inflammatory, or glial activation, suggesting that the observed beneficial effects may be mediated through non-neuroprotective mechanisms. Our data indicate that ELF-EMFs have an influence on functional recovery after stroke, and this effect is contingent upon the specific frequency used. These findings underscore the critical importance of optimizing the protocol parameters to maximize the beneficial effects of ELF-EMF. Further research is warranted to elucidate the underlying mechanisms and refine the protocol parameters for optimal therapeutic outcomes in stroke rehabilitation.
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Affiliation(s)
- Naohiko Okabe
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA.
| | - Mary Hovanesyan
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA
| | - Srbui Azarapetian
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA
| | - Weiye Dai
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA
| | | | | | | | - Esther Shohami
- BrainQ Technologies, Ltd., Jerusalem, Israel
- Hebrew University of Jerusalem, Jerusalem, Israel
| | - Yaron Segal
- BrainQ Technologies, Ltd., Jerusalem, Israel
| | - S Thomas Carmichael
- Department of Neurology, David Geffen School of Medicine, UCLA, Los Angeles, CA, 90095, USA
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25
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Diao Y, Liu L, Deng N, Lyu S, Hirata A. Tensor-conductance model for reducing the computational artifact in target tissue for low-frequency dosimetry. Phys Med Biol 2023; 68:205014. [PMID: 37722382 DOI: 10.1088/1361-6560/acfae0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 09/18/2023] [Indexed: 09/20/2023]
Abstract
Objective.In protecting human from low-frequency (<100 kHz) exposure, an induced electric field strength is used as a physical quantity for assessment. However, the computational assessment suffers from a staircasing error because of the approximation of curved boundary discretized with cubic voxels. The international guidelines consider an additional reduction factor of 3 when setting the limit of external field strength computed from the permissible induced electric field. Here, a new method was proposed to reduce the staircasing error considering the tensor conductance in human modeling for low-frequency dosimetry.Approach.We proposed a tensor-based conductance model, which was developed on the basis of the filling ratio and the direction of the tissue interface to satisfy the electric field boundary condition and reduce staircasing errors in the target tissue of a voxel human model.Main results.The proposed model was validated using two-layer nonconcentric cylindrical and spherical models with different conductivity contrasts. A comparison of induced electric field strengths with solutions obtained using an analytical formula and finite element method simulation indicated that for a wide range of conductivity ratios, staircasing errors were reduced compared with a conventional scalar-potential finite-difference method. The induced electric field in a simple anatomical head model using our approach was in good agreement with finite element method for exposure to uniform magnetic field exposure and that from coil, simulating transcranial magnetic stimulation.Significance.The proposed tensor-conductance model demonstrated that the staircasing error in an inner target tissue of a voxel human body can be reduced. This finding can be used for the electromagnetic compliance assessment and dose evaluation in electric or magnetic stimulation at low frequencies.
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Affiliation(s)
- Yinliang Diao
- College of Electronic Engineering, College of Artificial Intelligence, South China Agricultural University, Guangzhou 510642, People's Republic of China
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| | - Li Liu
- College of Electronic Engineering, College of Artificial Intelligence, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Nuo Deng
- College of Electronic Engineering, College of Artificial Intelligence, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Shilei Lyu
- College of Electronic Engineering, College of Artificial Intelligence, South China Agricultural University, Guangzhou 510642, People's Republic of China
| | - Akimasa Hirata
- Department of Electrical and Mechanical Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
- Center of Biomedical Physics and Information Technology, Nagoya Institute of Technology, Nagoya 466-8555, Japan
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26
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Tian H, Zhu H, Gao C, Shi M, Yang D, Jin M, Wang F, Sui X. System-level biological effects of extremely low-frequency electromagnetic fields: an in vivo experimental review. Front Neurosci 2023; 17:1247021. [PMID: 37869515 PMCID: PMC10590107 DOI: 10.3389/fnins.2023.1247021] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2023] [Accepted: 09/12/2023] [Indexed: 10/24/2023] Open
Abstract
During the past decades, the potential effects of extremely low-frequency electromagnetic fields (ELF-EMFs) on human health have gained great interest all around the world. Though the International Commission on Non-Ionizing Radiation Protection recommended a 100 μT, and then a 200 μT magnetic field limit, the long-term effects of ELF-EMFs on organisms and systems need to be further investigated. It was reported that both electrotherapy and possible effects on human health could be induced under ELF-EM radiation with varied EM frequencies and fields. This present article intends to systematically review the in vivo experimental outcome and the corresponding mechanisms to shed some light on the safety considerations of ELF-EMFs. This will further advance the subsequent application of electrotherapy in human health.
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Affiliation(s)
- Haoyang Tian
- Electric Power Research Institute, State Grid Shanghai Municipal Electric Power Company, Shanghai, China
| | - Haozheng Zhu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Chenhao Gao
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Mingxia Shi
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Dekun Yang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Mingyu Jin
- State Grid Shanghai Municipal Electric Power Company, Shanghai, China
| | - Fenghua Wang
- Department of Electrical Engineering, School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaohong Sui
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
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27
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Wase A, Hussain UA, Ratajczak T, Aung TT, Ali O, Markert RJ. The Impact of Electromagnetic Interference from Charging All-electric Vehicles on Implantable Cardioverter-defibrillator Performance. J Innov Card Rhythm Manag 2023; 14:5600-5604. [PMID: 37927392 PMCID: PMC10621619 DOI: 10.19102/icrm.2023.14102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 05/12/2023] [Indexed: 11/07/2023] Open
Abstract
Electric vehicles (EVs) are growing in popularity and in general use. The effect of electromagnetic interference (EMI) caused by supercharging all-electric vehicles on implantable cardioverter-defibrillator (ICD) function has not been studied. The objective of this study was to determine the extent of the effect of EMI from charging Tesla all-electric vehicles (Tesla, Inc., Austin, TX, USA) on cardiac implantable electronic device function. A proof-of-concept study was performed to explore the potential effect of EMI from Tesla vehicles while charging the battery using a 220-V wall charger and a 480-V Supercharger. Tesla Model S and Model X vehicles were used for this study. We enrolled 34 patients with stable ICD function for the initial phase using the standard wall charger, followed by an additional 35 patients for the second phase using the Supercharger. Tracings were obtained at nominal and highest sensitivity settings while patients sat in the driver's seat, passenger seat, back seats, and facing the charging port. In each position, the device and the patient were monitored in real time by a certified technician for any inappropriate sensing and/or delivery of therapies. A medical magnet was also available on site. Emergency medical services and physician supervision were available at all times, and patients were contacted the following day to ensure their well-being. No device interactions were identified at both the nominal and highest sensitivity settings of each ICD during exposure to vehicle charging using a Tesla 220-V wall charger and a 480-V Supercharger at any of the five positions in and around each vehicle. Interaction was defined as oversensing, undersensing, mode switch, or upper rate tracking behavior. There was also no damage to any ICD, and no inappropriate shocks were administered to any patient. In conclusion, transvenous ICD function is not interrupted by EMI transmitted while charging Tesla vehicles using either the 220-V wall charger or the 480-V Supercharger.
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Affiliation(s)
- Abdul Wase
- Department of Internal Medicine, Wright State University Boonshoft School of Medicine, Wright State University, Dayton, OH, USA
| | - Umbreen Azmat Hussain
- Department of Medicine, University Hospitals Cleveland Medical Center/Case Western Reserve University, Cleveland, OH, USA
| | | | | | - Omair Ali
- MultiCare Medical Associates, Tacoma, WA, USA
| | - Ronald J. Markert
- Department of Internal Medicine and Neurology, Wright State University Boonshoft School of Medicine, Dayton, OH, USA
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28
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Kursawe M, Kaifie A, Krabbe J, Kimpeler S, Kühn R, Kraus T, Jankowiak K. The role of the DC component in human perception of AC-DC hybrid electric fields and a comparison with the AC component. Sci Rep 2023; 13:16320. [PMID: 37770510 PMCID: PMC10539523 DOI: 10.1038/s41598-023-43556-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 09/26/2023] [Indexed: 09/30/2023] Open
Abstract
As part of the energy transition in Germany, high-voltage overhead power lines will be operated using hybrid systems that combine alternating and direct current (AC and DC). The degree to which humans perceive hybrid electric fields (EFs) is dependent on the proportion of both EF types. To investigate the impact of the DC component, a study assessed 49 participants with above-average EF detection ability under conditions with a low DC component of 1-4 kilovolts per meter (kV/m) and varying AC EFs between 1 and 14 kV/m. The detection thresholds of combined AC/DC EFs decreased with an increase in the DC component and ranged from 9.6 to 6.83 kV/m on average for the group. The results suggest that even minor variations in the DC component significantly affect human perception of hybrid EFs. These findings complement the results of an earlier study that investigated the AC component in hybrid EFs. Correlational analyses of both studies demonstrated the reliability of participants' performance. This study contributes to our understanding of EF-related effects on human perception and can aid in the planning of energy transmission near areas where humans work or live.
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Affiliation(s)
- Michael Kursawe
- Research Center for Bioelectromagnetic Interaction (femu), Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany.
| | - Andrea Kaifie
- Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Julia Krabbe
- Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Simon Kimpeler
- Institute for High Voltage Equipment and Grids, Digitalization and Power Economics, RWTH Aachen University, Aachen, Germany
| | - Ralph Kühn
- Research Center for Bioelectromagnetic Interaction (femu), Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Thomas Kraus
- Research Center for Bioelectromagnetic Interaction (femu), Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
- Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
| | - Kathrin Jankowiak
- Research Center for Bioelectromagnetic Interaction (femu), Institute for Occupational, Social and Environmental Medicine, Uniklinik RWTH Aachen University, Pauwelsstraße 30, 52074, Aachen, Germany
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Van de Steene T, Tanghe E, Martens L, Garripoli C, Stanzione S, Joseph W. Optimal Frequency and Wireless Power Budget for Miniature Receivers in Obese People. SENSORS (BASEL, SWITZERLAND) 2023; 23:8084. [PMID: 37836914 PMCID: PMC10574982 DOI: 10.3390/s23198084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/19/2023] [Accepted: 09/21/2023] [Indexed: 10/15/2023]
Abstract
This study investigates wireless power transfer for deep in-body receivers, determining the optimal frequency, power budget, and design for the transmitter and receiver. In particular, the focus is on small, in-body receivers at large depths up to 20 cm for obese patients. This enables long-term monitoring of the gastrointestinal tract for all body types. Numerical simulations are used to investigate power transfer and losses as a function of frequency and to find the optimal design at the selected frequency for an obese body model. From all ISM-frequencies in the investigated range (1 kHz-10 GHz), the value of 13.56 MHz yields the best performance. This optimum corresponds to the transition from dominant copper losses in conductors to dominant losses in conductive tissue. At this frequency, a transmitting and receiving coil are designed consisting of 12 and 23 windings, respectively. With a power transfer efficiency of 2.70×10-5, 18 µW can be received for an input power of 0.68 W while still satisfying exposure guidelines. The power transfer is validated by measurements. For the first time, efficiency values and the power budget are reported for WPT through 20 cm of tissue to mm sized receivers. Compared to WPT at higher frequencies, as commonly used for small receivers, the proposed system is more suitable for WPT to large depths in-body and comes with the advantage that no focusing is required, which can accommodate multiple receivers and uncertainty about receiver location more easily. The received power allows long-term sensing in the gastrointestinal tract by, e.g., temperature, pressure, and pH sensors, motility sensing, or even gastric stimulation.
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Affiliation(s)
- Tom Van de Steene
- Department of Information Technology, Ghent University/imec, B-9052 Ghent, Belgium
| | - Emmeric Tanghe
- Department of Information Technology, Ghent University/imec, B-9052 Ghent, Belgium
| | - Luc Martens
- Department of Information Technology, Ghent University/imec, B-9052 Ghent, Belgium
| | | | | | - Wout Joseph
- Department of Information Technology, Ghent University/imec, B-9052 Ghent, Belgium
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30
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Jamal L, Yahia-Cherif L, Hugueville L, Mazet P, Lévêque P, Selmaoui B. Assessment of Electrical Brain Activity of Healthy Volunteers Exposed to 3.5 GHz of 5G Signals within Environmental Levels: A Controlled-Randomised Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6793. [PMID: 37754652 PMCID: PMC10530694 DOI: 10.3390/ijerph20186793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2023] [Revised: 09/12/2023] [Accepted: 09/13/2023] [Indexed: 09/28/2023]
Abstract
Following the recent deployment of fifth-generation (5G) radio frequencies, several questions about their health impacts have been raised. Due to the lack of experimental research on this subject, the current study aimed to investigate the bio-physiological effects of a generated 3.5 GHz frequency. For this purpose, the wake electroencephalograms (EEG) of 34 healthy volunteers were explored during two "real" and "sham" exposure sessions. The electromagnetic fields were antenna-emitted in an electrically shielded room and had an electrical field root-mean-square intensity of 2 V/m, corresponding to the current outdoor exposure levels. The sessions were a maximum of one week apart, and both contained an exposure period of approximately 26 min and were followed by a post-exposure period of 17 min. The power spectral densities (PSDs) of the beta, alpha, theta, and delta bands were then computed and corrected based on an EEG baseline period. This was acquired for 17 min before the subsequent phases were recorded under two separate conditions: eyes open (EO) and eyes closed (EC). A statistical analysis showed an overall non-significant change in the studied brain waves, except for a few electrodes in the alpha, theta, and delta spectra. This change was translated into an increase or decrease in the PSDs, in response to the EO and EC conditions. In conclusion, this studhy showed that 3.5 GHz exposure, within the regulatory levels and exposure parameters used in this protocol, did not affect brain activity in healthy young adults. Moreover, to our knowledge, this was the first laboratory-controlled human EEG study on 5G effects. It attempted to address society's current concern about the impact of 5G exposure on human health at environmental levels.
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Affiliation(s)
- Layla Jamal
- Department of Experimental Toxicology and Modeling (TEAM), Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France;
- PériTox Laboratory (UMR_I 01), INERIS/UPJV, INERIS, 60550 Verneuil en Halatte, France
| | - Lydia Yahia-Cherif
- Paris Brain Institute (ICM), Center for NeuroImaging Research (CENIR), Sorbonne University, INSERM U1127, CNRS UMR7225, Pitié-Salpêtrière Hospital, 75013 Paris, France; (L.Y.-C.); (L.H.)
| | - Laurent Hugueville
- Paris Brain Institute (ICM), Center for NeuroImaging Research (CENIR), Sorbonne University, INSERM U1127, CNRS UMR7225, Pitié-Salpêtrière Hospital, 75013 Paris, France; (L.Y.-C.); (L.H.)
| | - Paul Mazet
- Technical Centre for Mechanical Industries (CETIM), 52 Avenue Félix Louat, 60300 Senlis, France;
| | - Philippe Lévêque
- XLIM Research Institute, University of Limoges, UMR CNRS 7252, 123 Avenue Albert Thomas, 87000 Limoges, France;
| | - Brahim Selmaoui
- Department of Experimental Toxicology and Modeling (TEAM), Institut National de l’Environnement Industriel et des Risques (INERIS), Parc Technologique Alata, BP 2, 60550 Verneuil-en-Halatte, France;
- PériTox Laboratory (UMR_I 01), INERIS/UPJV, INERIS, 60550 Verneuil en Halatte, France
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31
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Hansson Mild K, Mattsson MO, Jeschke P, Israel M, Ivanova M, Shalamanova T. Occupational Exposure to Electromagnetic Fields-Different from General Public Exposure and Laboratory Studies. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6552. [PMID: 37623138 PMCID: PMC10454245 DOI: 10.3390/ijerph20166552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/21/2023] [Accepted: 07/29/2023] [Indexed: 08/26/2023]
Abstract
The designs of in vivo, in vitro and in silico studies do not adequately reflect the characteristics of long-term occupational EMF exposure; the higher exposure levels permitted for employees are nevertheless extrapolated on this basis. Epidemiological studies consider occupational exposure only in a very general way, if at all. There is a lack of detailed descriptive data on long-term occupational exposure over the duration of the working life. Most studies reflect exposure characteristics of the general population, exposures which are long-term, but at a comparably low level. Occupational exposure is often intermittent with high peak power followed by periods with no exposure. Furthermore, the EU EMF-Directive 2013/35/EU states a demand for occupational health surveillance, the outcome of which would be of great help to epidemiologists studying the health effects of EMF exposure. This paper thus aims to outline and specify differences between public and occupational exposure and to increase the understanding of specific aspects of occupational exposure which are important for long-term health considerations. This could lead to a future protection concept against possible hazards based on adequate descriptions of long-term exposures and also include supplementary descriptive features such as a "reset time" of biological systems and accurate dose quantities.
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Affiliation(s)
- Kjell Hansson Mild
- Department of Radiation Sciences, Radiation Physics, Umeå University, 90187 Umeå, Sweden;
| | - Mats-Olof Mattsson
- SciProof International AB, 83158 Östersund, Sweden
- Institute of Advanced Studies, Strömstad Academy, 45280 Strömstad, Sweden
| | - Peter Jeschke
- Federal Institute for Occupational Safety and Health, 44194 Dortmund, Germany;
| | - Michel Israel
- National Centre of Public Health and Analyses, 1431 Sofia, Bulgaria; (M.I.); (M.I.); (T.S.)
| | - Mihaela Ivanova
- National Centre of Public Health and Analyses, 1431 Sofia, Bulgaria; (M.I.); (M.I.); (T.S.)
| | - Tsvetelina Shalamanova
- National Centre of Public Health and Analyses, 1431 Sofia, Bulgaria; (M.I.); (M.I.); (T.S.)
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32
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Lin GB, Chen WT, Kuo YY, Chen YM, Liu HH, Chao CY. Protection of high-frequency low-intensity pulsed electric fields and brain-derived neurotrophic factor for SH-SY5Y cells against hydrogen peroxide-induced cell damage. Medicine (Baltimore) 2023; 102:e34460. [PMID: 37543811 PMCID: PMC10403004 DOI: 10.1097/md.0000000000034460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 08/07/2023] Open
Abstract
Neurodegenerative diseases (NDDs) pose a significant global health threat. In particular, Alzheimer disease, the most common type causing dementia, remains an incurable disease. Alzheimer disease is thought to be associated with an imbalance of reactive oxygen species (ROS) in neurons, and scientists considered ROS modulation as a promising strategy for novel remedies. In the study, human neural cell line SH-SY5Y was used in probing the effect of combining noninvasive high-frequency low-intensity pulsed electric field (H-LIPEF) and brain-derived neurotrophic factor (BDNF) in protection against hydrogen peroxide (H2O2)-induced neuron damage. Our result finds that the combination approach has intensified the neuroprotective effect significantly, perhaps due to H-LIPEF and BDNF synergistically increasing the expression level of the phosphorylated epidermal growth factor receptor (p-EGFR), which induces the survival-related mitogen-activated protein kinases (MAPK) proteins. The study confirmed the activation of extracellular signal-regulated kinase (ERK) and the downstream pro-survival and antioxidant proteins as the mechanism underlying neuron protection. These findings highlighted the potential of H-LIPEF combined with BDNF in the treatment of NDDs. Furthermore, BDNF-mimetic drugs combining with noninvasive H-LIPEF to patients is a promising approach worthy of further research. This points to strategies for selecting drugs to cooperate with electric fields in treating neurodegenerative disorders.
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Affiliation(s)
- Guan-Bo Lin
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Wei-Ting Chen
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - Yu-Yi Kuo
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
| | - You-Ming Chen
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
| | - Hsu-Hsiang Liu
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
| | - Chih-Yu Chao
- Biomedical & Molecular Imaging Center, National Taiwan University College of Medicine, Taipei, Taiwan
- Department of Physics, Lab for Medical Physics & Biomedical Engineering, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Applied Physics, Biophysics Division, National Taiwan University, Taipei, Taiwan
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33
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Shaier AA, Mohamed AAS, Metwally H, Selem SI. A new hollow solenoid receiver compatible with the global double-D transmitter for EV inductive charging. Sci Rep 2023; 13:11925. [PMID: 37488164 PMCID: PMC10366217 DOI: 10.1038/s41598-023-38645-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Accepted: 07/12/2023] [Indexed: 07/26/2023] Open
Abstract
Inductive power transfer (IPT) technology is a promising solution for charging the electric vehicles (EVs) by enabling an EV to charge its energy storage system (battery) without any connecting wires through magnetic coupling. This paper proposes a new receiver design named Hollow Solenoid receiver that is compatible with the standard double-D transmitter defined by the SAE J2954 standard. A deep design analysis for the proposed Hollow Solenoid receiver is presented to define the optimum design parameters for coil (inductances, number of turns, dimensions, wires, etc.) and ferrite core (dimensions, number, arrangement, etc.). Several WPT3 (11.1kVA) solenoid receiver (SR) designs were presented and analyzed based on efficiency, weight, size, volume, and cost. The performance of the proposed SR was compared with the global Double-D receiver (DDR) presented by the SAE J2954 standard under different lateral and rotational alignment and loading conditions considering coupling factor, transmission power and efficiency, and stray electromagnetic fields (EMFs). The entire IPT system including coils, compensation network, power converters, controls, and battery load was modeled and analyzed for both SR and DDR coils. The results reveal that the proposed SR is compatible with the global DD transmitter at different alignment and loading conditions and is able to transmit the desired power (11 kW) at an efficiency > 85%. Hollow SR design shows the highest efficiency and lowest size, weight, and cost compared to DDR and other designs.
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Affiliation(s)
- Ahmed A Shaier
- Electrical Power and Machines Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt.
| | | | - Hamid Metwally
- Electrical Power and Machines Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt
| | - Sameh I Selem
- Electrical Power and Machines Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt
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34
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Goodall S, Ansdell P, Thomas K, Howatson G. Magnetic stimulation and the control of electromagnetic fields at work act (2016): an update. Brain Stimul 2023; 16:1097-1098. [PMID: 37380100 DOI: 10.1016/j.brs.2023.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Accepted: 06/25/2023] [Indexed: 06/30/2023] Open
Affiliation(s)
- Stuart Goodall
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK.
| | - Paul Ansdell
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Kevin Thomas
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
| | - Glyn Howatson
- Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne, UK
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35
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Gleich B, Schmale I, Nielsen T, Rahmer J. Miniature magneto-mechanical resonators for wireless tracking and sensing. Science 2023; 380:966-971. [PMID: 37262171 DOI: 10.1126/science.adf5451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 05/03/2023] [Indexed: 06/03/2023]
Abstract
Sensor miniaturization enables applications such as minimally invasive medical procedures or patient monitoring by providing process feedback in situ. Ideally, miniature sensors should be wireless, inexpensive, and allow for remote detection over sufficient distance by an affordable detection system. We analyze the signal strength of wireless sensors theoretically and derive a simple design of high-signal resonant magneto-mechanical sensors featuring volumes below 1 cubic millimeter. As examples, we demonstrate real-time tracking of position and attitude of a flying bee, navigation of a biopsy needle, tracking of a free-flowing marker, and sensing of pressure and temperature, all in unshielded environments. The achieved sensor size, measurement accuracy, and workspace of ~25 centimeters show the potential for a low-cost wireless tracking and sensing platform for medical and nonmedical applications.
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36
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Goiceanu C, Danulescu R, Danulescu E. Some considerations on the challenges related to the use of the new ICNIRP restrictions for human exposure to radiofrequency fields. RADIATION PROTECTION DOSIMETRY 2023; 199:818-825. [PMID: 37225206 DOI: 10.1093/rpd/ncad084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
ICNIRP 2020 guidelines for limiting exposure to radiofrequency fields replace the radiofrequency part of the ICNIRP 1998 guidelines for limiting exposure to time-varying electric, magnetic and electromagnetic fields. Besides setting new restrictions that prevent thermal effect they also took over the 100 kHz to 10 MHz part of the ICNIRP 2010 guidelines for limiting exposure to low-frequency electromagnetic fields, which provides restrictions that prevent nerve stimulation effect. The latest guidelines brought many changes to the system of protection against exposure to radiofrequency fields starting with the physical quantities used to express restrictions and continuing with specific restrictions and new exposure metrics employed. For the first time, the case of brief local exposure to intense radiofrequency fields was accounted by ICNIRP for setting new types of exposure restrictions. All these changes led to more detailed and complex guidelines, but their provisions are more difficult to apply in practice. Our paper presents some of the challenges related to the use in practice of the new ICNIRP restrictions for human exposure to radiofrequency fields.
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Affiliation(s)
- Cristian Goiceanu
- Department of Environmental Health, National Institute of Public Health, Regional Centre Iasi, Iasi 700465, Romania
| | - Razvan Danulescu
- Department of Environmental Health, National Institute of Public Health, Regional Centre Iasi, Iasi 700465, Romania
| | - Eugenia Danulescu
- Department of Environmental Health, National Institute of Public Health, Regional Centre Iasi, Iasi 700465, Romania
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Hasmat S, Lovell NH, Low THH, Clark JR. Development of an implantable bionic for dynamic eye closure in facial nerve paralysis: Evolution of the design. Med Eng Phys 2023; 115:103977. [PMID: 37120171 DOI: 10.1016/j.medengphy.2023.103977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Revised: 01/03/2023] [Accepted: 04/06/2023] [Indexed: 05/01/2023]
Abstract
Facial nerve paralysis (FNP) presents with a constellation of clinical problems but its most concerning consequence is corneal exposure from lack of blinking. Bionic lid implant for natural closure (BLINC) is an implantable solution for dynamic eye closure in FNP. It uses an electromagnetic actuator to mobilise the dysfunctional eyelid by means of an eyelid sling. This study highlights issues relating to device biocompatibility and describes its evolution to overcome some of these issues. The essential components of the device are the actuator, the electronics including energy storage, and an induction link for wireless power transfer. Effective arrangement of these components within the anatomical confines and their integration is achieved through a series of prototypes. The response of each prototype is tested in a synthetic or cadaveric model for eye closure with the final prototype designed for acute and chronic animal trials.
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Affiliation(s)
- Shaheen Hasmat
- Faculty of Medicine and Health, the University of Sydney, Camperdown, NSW 2006, Australia; Department of Head and Neck Surgery, Chris O'Brien Lifehouse, Camperdown, NSW 2050, Australia.
| | - Nigel H Lovell
- Graduate School of Biomedical Engineering, UNSW Sydney, NSW 2052, Australia
| | - Tsu-Hui Hubert Low
- Faculty of Medicine and Health, the University of Sydney, Camperdown, NSW 2006, Australia; Department of Head and Neck Surgery, Chris O'Brien Lifehouse, Camperdown, NSW 2050, Australia
| | - Jonathan R Clark
- Faculty of Medicine and Health, the University of Sydney, Camperdown, NSW 2006, Australia; Department of Head and Neck Surgery, Chris O'Brien Lifehouse, Camperdown, NSW 2050, Australia
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Triviño A, Casaucao I, Quirós JC, Pérez P, Rojas A. Novel sustainable magnetic material to improve the wireless charging of a lightweight drone. RSC Adv 2023; 13:10556-10563. [PMID: 37025663 PMCID: PMC10071304 DOI: 10.1039/d2ra07800g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 03/20/2023] [Indexed: 04/07/2023] Open
Abstract
Unmanned aerial vehicles are clear candidates to benefit from wireless power transfer, as it can facilitate their charging process and even allow them to charge autonomously. One common approach when designing a wireless power transfer (WPT) system is to incorporate ferromagnetic material to guide the magnetic field and improve system efficiency. However, a complex optimization calculation must be carried out to determine the positions and size of the ferromagnetic material and thereby restrict the additional weight imposed. This is severely limiting in the case of lightweight drones. To alleviate this burden, we show the feasibility of incorporating a novel sustainable magnetic material, called MagPlast 36-33, which has two main features. First, it is lighter than ferrite tiles and can therefore be used without having to consider complex geometries to reduce the weight. In addition, its manufacturing process is based on the principle of sustainability, since it is produced from recycled ferrite scrap generated in the industry. Its physical characteristics and properties mean that it can be used to improve the efficiency of the wireless charger, adding a weight lower than that of conventional ferrites. The experimental results we obtained in the laboratory demonstrate the feasibility of using this type of recycled material in lightweight drones operating at the frequency imposed by SAE J-2954. Furthermore, we have conducted a comparative analysis with a different ferromagnetic material commonly used in WPT systems, in order to verify the benefits of our proposal.
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Affiliation(s)
- Alicia Triviño
- Department of Electrical Engineering, University of Malaga Malaga 29071 Spain
| | - Inmaculada Casaucao
- Department of Electrical Engineering, University of Malaga Malaga 29071 Spain
| | - Juan Carlos Quirós
- Department of Electrical Engineering, University of Malaga Malaga 29071 Spain
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Moslemi S, Ghotbi Ravandi MR, Zare S, Tohidi Nik H. Measuring and assessing the effects of extremely low-frequency electromagnetic fields (ELF-EMF) on blood parameters and liver enzymes of personnel working in high voltage power stations in a petrochemical industry. Heliyon 2023; 9:e15414. [PMID: 37151699 PMCID: PMC10161571 DOI: 10.1016/j.heliyon.2023.e15414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Revised: 04/05/2023] [Accepted: 04/06/2023] [Indexed: 05/09/2023] Open
Abstract
Introduction Exposure to electric and magnetic fields (EMF) is a phenomenon that has always been present. In the last two decades, there have been numerous worries about the possible effects of extremely low-frequency (ELF) fields on human health. Consequently, this study aims to measure and evaluate the effect of ELF fields on blood parameters and liver enzymes of personnel working in high-voltage power stations in the petrochemical industry. Methods This cross-sectional, descriptive-analytical study was done in a petrochemical industry in southern Iran in 2021. Two groups of 50 people were selected to attain the research goals and classify jobs with the risk of exposure to extremely low-frequency electromagnetic fields (ELF-EMF) and the time spent on work. One group was exposed to ELF-EMF, and the other was regarded as the control group. Electromagnetic fields were measured using the HI-3604 device and the standard method of IEEE 1994-644. The workers' demographic data, blood parameters, and liver enzymes were also obtained from the workers' medical records. The course of changes in each of the blood parameters and liver enzymes and demographic variables in the control and case groups were then examined. In the last stage, the effect of the electric field and magnetic field on the blood parameters and liver enzymes of the two control and subject groups was conducted using the multiple regression model. Results The measured points in all stations are 200, and the minimum and maximum values of the magnetic field was 0.8 and 2019 mG, respectively. The minimum and maximum values of the electric field intensity was 0.003 and 215 V/m, respectively. The average results of the demographic variables and blood and liver indices in the control and case groups from 2018 to 2020 revealed that the average variables were not significantly different in the case and control groups (p-value>0.05). Moreover, workers' exposure to ELF-EMF was below the permissible limit. Conclusion Based on the results of the present study, ELF-EMF does not have any significant effects on demographic factors, blood parameters, and liver enzymes.
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Affiliation(s)
- Soode Moslemi
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Reza Ghotbi Ravandi
- Department of Occupational Health Engineering and Safety at Work, Faculty of Public Health, Kerman University of Medical Sciences, Kerman, Iran
| | - Sajad Zare
- Department of Occupational Health Engineering and Safety at Work, Faculty of Public Health, Kerman University of Medical Sciences, Kerman, Iran
- Modeling in Health Research Center, Institute for Future Studies in Health, Kerman University of Medical Sciences, Kerman, Iran
- Corresponding author. Department of Occupational Health Engineering and Safety at Work, Faculty of Public Health, Kerman University of Medical Sciences, Kerman, Iran.
| | - Hamidreza Tohidi Nik
- Department of Statistics and Epidemiology, School of Public Health, Kerman University of Medical Sciences, Kerman, Iran
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Cook N, Shelton N, Gibson S, Barnes P, Alinaghi-Zadeh R, Jameson MG. ACPSEM position paper: the safety of magnetic resonance imaging linear accelerators. Phys Eng Sci Med 2023; 46:19-43. [PMID: 36847966 PMCID: PMC10030425 DOI: 10.1007/s13246-023-01224-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/19/2023] [Indexed: 03/01/2023]
Abstract
Magnetic Resonance Imaging linear-accelerator (MRI-linac) equipment has recently been introduced to multiple centres in Australia and New Zealand. MRI equipment creates hazards for staff, patients and others in the MR environment; these hazards must be well understood, and risks managed by a system of environmental controls, written procedures and a trained workforce. While MRI-linac hazards are similar to the diagnostic paradigm, the equipment, workforce and environment are sufficiently different that additional safety guidance is warranted. In 2019 the Australasian College of Physical Scientists and Engineers in Medicine (ACPSEM) formed the Magnetic Resonance Imaging Linear-Accelerator Working Group (MRILWG) to support the safe clinical introduction and optimal use of MR-guided radiation therapy treatment units. This Position Paper is intended to provide safety guidance and education for Medical Physicists and others planning for and working with MRI-linac technology. This document summarises MRI-linac hazards and describes particular effects which arise from the combination of strong magnetic fields with an external radiation treatment beam. This document also provides guidance on safety governance and training, and recommends a system of hazard management tailored to the MRI-linac environment, ancillary equipment, and workforce.
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Affiliation(s)
- Nick Cook
- Christchurch Hospital, Christchurch, New Zealand
| | - Nikki Shelton
- Olivia Newton-John Cancer Wellness and Research Centre, Heidelberg, VIC, Australia
| | | | | | - Reza Alinaghi-Zadeh
- Olivia Newton-John Cancer Wellness and Research Centre, Heidelberg, VIC, Australia
| | - Michael G Jameson
- GenesisCare, Sydney, NSW, Australia.
- University of New South Wales, Sydney, Australia.
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Nguyen H, Segers S, Ledent M, Anthonissen R, Verschaeve L, Hinsenkamp M, Collard JF, Feipel V, Mertens B. Effects of long-term exposure to 50 Hz magnetic fields on cell viability, genetic damage, and sensitivity to mutagen-induced damage. Heliyon 2023; 9:e14097. [PMID: 36923833 PMCID: PMC10008985 DOI: 10.1016/j.heliyon.2023.e14097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 02/14/2023] [Accepted: 02/21/2023] [Indexed: 03/02/2023] Open
Abstract
Until today, it remains controversial whether long-term exposure to extremely low-frequency magnetic fields (ELF-MF) below the legislative exposure limits could result in adverse human health effects. In the present study, the effects of long-term in vitro MF exposure on three different study endpoints (cell viability, genetic damage, and sensitivity to damage induced by known mutagens) were investigated in the human B lymphoblastoid (TK6) cell line. Cells were exposed to 50 Hz MF at three selected magnetic flux densities (i.e., 10, 100, and 500 μT) for different exposure periods ranging from 96h up to 6 weeks. Cell viability following MF exposure was assessed using the ATP-based cell viability assay. Effects of MF exposure on cell genetic damage and cell sensitivity to mutagen-induced damage were evaluated using the in vitro alkaline comet assay and the in vitro cytokinesis block micronucleus assay. The results showed that long-term exposure up to 96h to 50 Hz MF at all tested flux densities could significantly increase TK6 cell viability. In contrast, long-term MF exposure did not affect cell genetic damage, and long-term pre-exposure to MF did not change cell sensitivity to damage induced by known mutagens. At certain time points, statistically significant difference in genotoxicity test results were observed between the MF-exposed cells and the control cells. However, these observations could not be confirmed in the repeat experiments, indicating that they are probably not biologically significant.
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Affiliation(s)
- Ha Nguyen
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium.,Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | - Seppe Segers
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Maryse Ledent
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Roel Anthonissen
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Luc Verschaeve
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
| | - Maurice Hinsenkamp
- Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | | | - Veronique Feipel
- Faculty of Medicine, Universite Libre de Bruxelles, 1070 Brussels, Belgium
| | - Birgit Mertens
- Scientific Direction Chemical and Physical Health Risks, Sciensano, 1050 Ixelles, Belgium
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Seo S, Jo H, Kim J, Lee B, Bien F. An ultralow power wearable vital sign sensor using an electromagnetically reactive near field. Bioeng Transl Med 2023; 8:e10502. [DOI: 10.1002/btm2.10502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 12/31/2022] [Accepted: 02/12/2023] [Indexed: 03/01/2023] Open
Affiliation(s)
- Seoktae Seo
- Department of Electrical Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - Hyunkyeong Jo
- Department of Electrical Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - Jungho Kim
- Department of Electrical Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - Bonyoung Lee
- Department of Electrical Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
| | - Franklin Bien
- Department of Electrical Engineering Ulsan National Institute of Science and Technology Ulsan Republic of Korea
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Schneeweiss P, Hirtl R, Schmid G. Nonsinusoidal in situelectric field caused by magnetic deactivator device for EAS labels-assessment of field strength inside a detailed anatomical hand model. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2023; 43:011514. [PMID: 36745918 DOI: 10.1088/1361-6498/acb955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/06/2023] [Indexed: 06/18/2023]
Abstract
In order to evaluate the localised magnetic field (MF) exposure of the cashier's hand due to a particular demagnetization device (deactivator) for single-use labels of an acoustomagnetic (AM) electronic article surveillance (EAS) system, comprehensive measurements of the MF near the surface of the deactivator, and numerical computations of the induced electric field strengthEi, were performed in high-resolution anatomical hand models of different postures and positions with respect to the deactivator. The measurement results for magnetic inductionBwere assessed with respect to the action levels (AL) for limb exposure, and the computational results forEiwere evaluated with respect to the exposure limit values (ELV) for health effects according to European Union (EU) directive 2013/35/EU. For the ELV-based assessment, a maximum of the 2 × 2 × 2 mm3averagedEi(maxEi,avg) and the respective 99.9th, 99.5th, and 99.0th percentiles were used. As the MF impulse emitted by the deactivator for demagnetization of the AM-EAS labels was highly nonsinusoidal, measurement results were assessed based on the weighted peak method in the time domain (WPM-TD). A newly developed scaling technique was proposed to also apply the WPM-TD to the assessment of the (nonsinusoidal)Eiregarding the ELV. It was used to calculate the resulting WPM-TD-based exposure index (EI) from frequency domain computations. The assessment regarding the AL for limbs yielded peak values of magnetic induction of up to 97 mT (measured with a 3 cm2MF probe on top of the deactivator surface) corresponding to an EI of 443%. However, this was considered an overestimation of the actual exposure in terms ofEias the AL were intentionally defined conservatively. A WPM-TD-based assessment ofEifinally led to the worst case EI of up to 135%, 93%, 78%, and 72% when using the maxEi,avg, 99.9th, 99.5th, and 99.0th percentiles, respectively.
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Affiliation(s)
- Pia Schneeweiss
- Seibersdorf Laboratories, Department EMC & Optics, A-2444 Seibersdorf, Austria
| | - Rene Hirtl
- Seibersdorf Laboratories, Department EMC & Optics, A-2444 Seibersdorf, Austria
| | - Gernot Schmid
- Seibersdorf Laboratories, Department EMC & Optics, A-2444 Seibersdorf, Austria
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44
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Analysis of the Optimized Compensating Loops Effect on the Magnetic Induction Due to Very-High-Voltage Underground Cable Using Grey Wolf Optimizer. ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING 2023. [DOI: 10.1007/s13369-023-07656-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
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45
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Turajlic E, Alihodzic A, Mujezinovic A. ARTIFICIAL NEURAL NETWORK MODELS FOR ESTIMATION OF ELECTRIC FIELD INTENSITY AND MAGNETIC FLUX DENSITY IN THE PROXIMITY OF OVERHEAD TRANSMISSION LINE. RADIATION PROTECTION DOSIMETRY 2023; 199:107-115. [PMID: 36426744 DOI: 10.1093/rpd/ncac229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 04/20/2022] [Accepted: 10/12/2022] [Indexed: 06/16/2023]
Abstract
This paper considers the application of artificial neural network (ANN) models for electric field intensity and magnetic flux density estimation in the proximity of overhead transmission lines. Specifically, two distinct ANN models are used to facilitate independent estimation of electric field intensity and magnetic flux density in the proximity of overhead transmission lines. The considered ANN approach is systematically evaluated under different scenarios. An example of an overhead transmission line with horizontal phase conductor configuration is used to enable a direct comparison of the electric field intensity and magnetic flux density estimates generated by the two ANN models to measurement results obtained over the lateral profile. Further investigation of ANN models involves an extensive study whereby 13 different overhead transmission lines of horizontal configurations are used as the basis for comparing measurement results to estimates provided by the ANN models. In this study, the performance analysis of the ANN models was evaluated using coefficient of determination and root mean square error. The obtained results demonstrate that the considered ANN approach can be used to estimate the electric field intensity and magnetic flux density in the proximity of overhead transmission lines.
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Affiliation(s)
- Emir Turajlic
- Faculty of Electrical Engineering, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina
| | - Ajdin Alihodzic
- Faculty of Electrical Engineering, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina
| | - Adnan Mujezinovic
- Faculty of Electrical Engineering, University of Sarajevo, 71000 Sarajevo, Bosnia and Herzegovina
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Sundaram V, Mohammed S, Cockburn BN, Srinivasan MR, Venkata CRA, Johnson J, Gilkes L, Jones KR, Zyuzikov N. Effects of Intermediate Frequency (150 kHz) Electromagnetic Radiation on the Vital Organs of Female Sprague Dawley Rats. BIOLOGY 2023; 12:310. [PMID: 36829585 PMCID: PMC9952889 DOI: 10.3390/biology12020310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/09/2023] [Accepted: 02/13/2023] [Indexed: 02/17/2023]
Abstract
Exposure to electromagnetic radiation (EMR) from intermediate frequency sources has increased exponentially in recent years. The consequences of this exposure on biological systems are prompting scientists to study the effects on human health. This current study aimed to determine the effects of intermediate frequency (150 kHz) EMR exposure on the vital organs of female Sprague Dawley rats. The EMR group (n = 10 animals) was exposed to a frequency of 150 kHz with an intensity of 65 ± 15 μW/cm2 for two months. The control group (n = 10 animals) was exposed to an intensity of 35 ± 15 nW/cm2. Haematological, histochemical, gross, and histopathological profiles of all major organs of all animals were then performed using standard procedures. All major organs generally showed no significant detectable effects in either the control or EMR groups. However, gross and histopathological examinations revealed the effects of EMR on the liver and lungs, which showed inflammatory changes without significant biochemical/haematological manifestations. In addition, a significant increase in serum sodium level and a decrease in serum urea level were also observed in the EMR group. It can be concluded that the current frequency and duration of exposure trigger the changes in the liver and lungs but are not sufficient to cause clinical and functional manifestations. Therefore, a long-term exposure study might be helpful to determine the effects of 150 kHz IF EMR on these organs.
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Affiliation(s)
- Venkatesan Sundaram
- Department of Basic Veterinary Sciences, School of Veterinary Medicine, Faculty of Medical Sciences, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Stephanie Mohammed
- Department of Physics, Faculty of Science and Technology, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Brian N. Cockburn
- Department of Life Sciences, Faculty of Science and Technology, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - M. R. Srinivasan
- Laboratory Animal Medicine Unit, Directorate of Centre for Animal Health Studies, Tamil Nadu Veterinary and Animal Sciences University, Chennai 600016, Tamil Nadu, India
| | - Chalapathi R. Adidam Venkata
- Department of Paraclinical Sciences, Faculty of Medical Sciences, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Jenelle Johnson
- Department of Clinical Veterinary Sciences, School of Veterinary Medicine, Faculty of Medical Sciences, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Lester Gilkes
- Department of Basic Veterinary Sciences, School of Veterinary Medicine, Faculty of Medical Sciences, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Kegan Romelle Jones
- Department of Basic Veterinary Sciences, School of Veterinary Medicine, Faculty of Medical Sciences, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
| | - Nikolay Zyuzikov
- Department of Physics, Faculty of Science and Technology, The University of the West Indies, St. Augustine 999183, Trinidad and Tobago
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Lee HJ, Jin H, Ahn YH, Kim N, Pack JK, Choi HD, Lee YS. Effects of intermediate frequency electromagnetic fields: a review of animal studies. Int J Radiat Biol 2023; 99:166-182. [PMID: 35758938 DOI: 10.1080/09553002.2022.2094016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
PURPOSE Many novel devices such as induction cookers or wireless power transfer produce electromagnetic fields (EMFs) in the intermediate frequency (IF) range (300 Hz to 10 MHz) and it is very meaningful for summarizing the bioeffects of IF-EMF research, particularly animal studies. This review takes into account experimental studies that used murine models to study the health effects of exposure to IF-EMF. The analyses included here use data available in the literature published from January 1988 to August 2021 including the animal studies about general adverse effects, tumorigenic effects, and effects on developmental stages. The studies that linked IF-EMF exposure during pregnancy or neonatal stage to behavioral and cognition changes were included. Additionally, this review also covers the effects of IF-EMF on gene expression patterns in the brain, behavior patterns associated with learning and memory, and immune function. CONCLUSIONS Although most studies have suggested that IF-EMF is harmless, some adverse effects have been reported after exposure at developmental stages and prolonged exposure. Compared to extremely low frequency (ELF) or radiofrequency (RF) EMF bands, studies on health effects with more diverse perspectives of IF-EMF have not been conducted. Therefore, performing more research should be necessary using the latest biomedical tools. From this point of view, a comprehensive review of IF-EMF studies, particularly animal studies, will provide a valuable basis for further risk analysis in humans.
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Affiliation(s)
- Hae-June Lee
- Division of Basic Radiation Bioscience, Korea Institute of Radiological & Medical Sciences, Seoul, South Korea
| | - Hee Jin
- School of Pharmaceutical Sciences, Ewha Womans University, Seoul, South Korea
| | - Young Hwan Ahn
- Department of Neurosurgery, Ajou University School of Medicine, Suwon, South Korea
| | - Nam Kim
- School of Information and Communication Engineering, Chungbuk National University, Cheongju, South Korea
| | - Jeong Ki Pack
- Department of Radio and Information Communications Engineering, Chungnam National University, Daejeon, South Korea
| | - Hyung-Do Choi
- Radio & Satellite Research Division, Electronics and Telecommunications Research Institute, Daejeon, South Korea
| | - Yun-Sil Lee
- School of Pharmaceutical Sciences, Ewha Womans University, Seoul, South Korea
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KUZAY D, SİRAV B, ÖZER Ç. Effects of RF and ELF Radiation on Oxidative Stress of Brain Tissue and Plasma of Diabetic Rats. KOCAELI ÜNIVERSITESI SAĞLIK BILIMLERI DERGISI 2023. [DOI: 10.30934/kusbed.784547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Objective: Exposure to Radio Frequency (RF) and Extremely Low Frequency (ELF) radiation is increasing steadily with the progress of technology and industrialization. The aim of this study was to investigate whether RF and ELF radiation are oxidative stress effects in the plasma and brain tissue of diabetic and non-diabetic rats.
Methods: Experiment groups were designed as follows; C (control), S (sham), ELF (ELF radiation exposure), RF (RF radiation exposure), ELF+RF (ELF and RF radiation exposure), D-C (Diabetic Control), D-S (Diabetic Sham), D-ELF (Diabetic ELF), D-RF (Diabetic RF), D-ELF+RF (Diabetic ELF+RF). The experimental diabetes model was induced with a single dose of 65mg/kg streptozotocin (STZ). 2100 MHz RF and 50 Hz ELF radiation groups exposed for 1 month. Total nitric oxide (NOx), malondialdehyde (MDA) and total sulfhydryl groups (RSH) / glutathione (GSH) levels were measured in plasma and brain tissue.
Results: RF + ELF radiation exposure caused an increase in NOx and MDA levels in plasma and brain tissue of diabetic and non-diabetic rats (p<0.05). Exposure to RF and RF + ELF radiation caused a decrease in plasma RSH / tissue GSH levels in non-diabetic rats (p<0.05).
Conclusion: The most prominent effect was seen in the diabetic group with RF + ELF radiation exposure.
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Affiliation(s)
- Dilek KUZAY
- AHI EVRAN UNIVERSITY, FACULTY OF MEDICINE, DEPARTMENT OF BASIC MEDICAL SCIENCES, DEPARTMENT OF PHYSIOLOGY
| | - Bahriye SİRAV
- GAZI UNIVERSITY, FACULTY OF MEDICINE, DEPARTMENT OF BASIC MEDICAL SCIENCES, DEPARTMENT OF BIOPHYSICS
| | - Çiğdem ÖZER
- GAZI UNIVERSITY, FACULTY OF MEDICINE, DEPARTMENT OF BASIC MEDICAL SCIENCES, DEPARTMENT OF PHYSIOLOGY
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Emeksiz C. Investigation of extremely low-frequency (1 Hz-400 kHz) pollution frequently encountered in social life: a case study of a shopping mall. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:23796-23809. [PMID: 36327086 DOI: 10.1007/s11356-022-23843-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 10/22/2022] [Indexed: 06/16/2023]
Abstract
It is important to periodically measure, analyze, and map electromagnetic radiation levels due to potential risks. This study aims to draw attention to new electromagnetic pollution caused by radio frequencies and extremely low frequencies. For this reason, electric field and magnetic field measurements were carried out in the 1-Hz-400-kHz frequency band in a shopping mall, where electronic devices cause low-frequency electromagnetic radiation intensively. The measurements were performed with the EHP-50F device for 24 h a day for a week. The measurements were made at 10 points in the shopping mall, and the measurement results were evaluated over five different sectors: electronics, clothing and accessories (male-female), personal care and cosmetics, supermarket, and the playland for children. Magnetic maps of each sector were produced. In addition, the specific absorption rates (SAR) of male and female customers in these workplaces were determined. This is the first study carried out to find SAR caused by low-frequency radiation. Although the safe limit value of SAR for the whole body is 0.08 W/kg, the SAR values calculated in the playland and electronics sectors were obtained to be 0.763 and 0.39 W/kg, respectively. Results clearly demonstrate how especially small children are exposed to danger in the long term.
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Affiliation(s)
- Cem Emeksiz
- Department of Electric-Electronic Engineering, Faculty of Engineering and Architecture, Tokat Gaziosmanpasa University, 60150, Tokat, Turkey.
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Zhuang H, Wang W, Yan G. Ferrite Concentrating and Shielding Structure Design of Wireless Power Transmitting Coil for Inductively Coupled Capsule Robot. IEEE TRANSACTIONS ON BIOMEDICAL CIRCUITS AND SYSTEMS 2023; PP:45-53. [PMID: 37022243 DOI: 10.1109/tbcas.2023.3241194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
High permeability material, especially the ferrite, has been widely used in wireless power transfer (WPT) to enhance the power transfer efficiency (PTE). However, for the WPT system of inductively coupled capsule robot, the ferrite core is solely introduced in power receiving coil (PRC) configuration to enhance the coupling. As for the power transmitting coil (PTC), very few studies focus on the ferrite structure design, and only the magnetic concentrating is taken into account without careful design. Therefore, a novel ferrite structure for PTC giving consideration to the magnetic field concentration as well as the mitigation and shielding of the leaked magnetic field is proposed in this paper. The proposed design is realized by combing the ferrite concentrating part and shielding part into a whole and providing a low reluctance closed path for magnetic induction lines, thereby improving the inductive coupling and PTE. Through analyses and simulations, the parameters of the proposed configuration are designed and optimized in terms of average magnetic flux density, uniformity, and shielding effectiveness. Prototypes of PTC with different ferrite configurations are established, tested, and compared to validate the performance enhancement. The experimental results indicate that the proposed design notably improves the average power delivered to the load from 373 mW to 822 mW and the PTE from 7.47% to 16.44%, with a relative percentage difference of 119.9%. Moreover, the power transfer stability is slightly enhanced from 91.7% to 92.8%.
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