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1.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805726

RESUMO

An electromagnetic field (EMF) may affect the functions of uterine tissues. This study hypothesized that EMF changes the estrogenic activity of pig myometrium during the peri-implantation period. Tissue was collected on days 15-16 of the gestation and incubated in the presence of EMF (50 and 120 Hz, 2 and 4 h). The cytochrome P450 aromatase type 3 (CYP19A3) and hydroxysteroid 17ß dehydrogenase type 4 (HSD17B4) mRNA transcript abundance, cytochrome P450arom (aromatase), and 17ß hydroxysteroid dehydrogenase 17ßHSD) protein abundance and estrone (E1) and estradiol-17ß (E2) release were examined using Real-Time PCR, Western blot and radioimmunoassay. Selected myometrial slices were treated with progesterone (P4) to determine whether it functions as a protector against EMF. CYP19A3 mRNA transcript abundance in slices treated with EMF was less at 50 Hz (2 h) and greater at 120 Hz (2 and 4 h). HSD17B4 mRNA transcript was greater in slices treated with EMF at 120 Hz (2 h). Progesterone diminished EMF-related effects on CYP19A3 and HSD17B4. When P4 was added, EMF had suppressive (50 and 120 Hz, 2 h) or enhancing (50 Hz, 4 h) effects on aromatase abundance. The E1 release was lower after 4 h of EMF treatment at 50 Hz and P4 did not protect myometrial E1 release. In conclusion, EMF alters the synthesis and release of E1 and did not affect E2 release in the myometrium during the peri-implantation period.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Implantação do Embrião/efeitos da radiação , Estradiol/metabolismo , Estrona/metabolismo , Regulação da Expressão Gênica/efeitos da radiação , Miométrio/efeitos da radiação , Animais , Aromatase/genética , Aromatase/metabolismo , Radiação Eletromagnética , Feminino , Miométrio/metabolismo , Proteína Multifuncional do Peroxissomo-2/genética , Proteína Multifuncional do Peroxissomo-2/metabolismo , Progesterona/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Suínos , Técnicas de Cultura de Tecidos
2.
Sensors (Basel) ; 21(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652644

RESUMO

A textile patch antenna is an attractive package for wearable applications as it offers flexibility, less weight, easy integration into the garment and better comfort to the wearer. When it comes to wearability, above all, comfort comes ahead of the rest of the properties. The air permeability and the water vapor permeability of textiles are linked to the thermophysiological comfort of the wearer as they help to improve the breathability of textiles. This paper includes the construction of a breathable textile rectangular ring microstrip patch antenna with improved water vapor permeability. A selection of high air permeable conductive fabrics and 3-dimensional knitted spacer dielectric substrates was made to ensure better water vapor permeability of the breathable textile rectangular ring microstrip patch antenna. To further improve the water vapor permeability of the breathable textile rectangular ring microstrip patch antenna, a novel approach of inserting a large number of small-sized holes of 1 mm diameter in the conductive layers (the patch and the ground plane) of the antenna was adopted. Besides this, the insertion of a large number of small-sized holes improved the flexibility of the rectangular ring microstrip patch antenna. The result was a breathable perforated (with small-sized holes) textile rectangular ring microstrip patch antenna with the water vapor permeability as high as 5296.70 g/m2 per day, an air permeability as high as 510 mm/s, and with radiation gains being 4.2 dBi and 5.4 dBi in the E-plane and H-plane, respectively. The antenna was designed to resonate for the Industrial, Scientific and Medical band at a specific 2.45 GHz frequency.


Assuntos
Têxteis , Dispositivos Eletrônicos Vestíveis , Tecnologia sem Fio , Radiação Eletromagnética , Desenho de Equipamento
3.
Sci Total Environ ; 767: 144913, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33636787

RESUMO

The biodiversity of insects is threatened worldwide. Numerous studies have reported the serious decline in insects that has occurred in recent decades. The same is happening with the important group of pollinators, with an essential utility for pollination of crops. Loss of insect diversity and abundance is expected to provoke cascading effects on food webs and ecosystem services. Many authors point out that reductions in insect abundance must be attributed mainly to agricultural practices and pesticide use. On the other hand, evidence for the effects of non-thermal microwave radiation on insects has been known for at least 50 years. The review carried out in this study shows that electromagnetic radiation should be considered seriously as a complementary driver for the dramatic decline in insects, acting in synergy with agricultural intensification, pesticides, invasive species and climate change. The extent that anthropogenic electromagnetic radiation represents a significant threat to insect pollinators is unresolved and plausible. For these reasons, and taking into account the benefits they provide to nature and humankind, the precautionary principle should be applied before any new deployment (such 5G) is considered.


Assuntos
Ecossistema , Polinização , Animais , Biodiversidade , Produtos Agrícolas , Radiação Eletromagnética , Insetos
4.
Artigo em Russo | MEDLINE | ID: mdl-33605129

RESUMO

Metabolic syndrome (MS) is a complex of interrelated metabolic disorders leading to the development of abdominal obesity, hyperglycemia, insulin resistance, and dyslipidemia. To develop new methods for the prevention and treatment of MS, it seems appropriate to simulate this disease using a high-calorie diet that induces many of its symptoms. As a therapeutic and prophylactic agent, it is promising to use low-intensity electromagnetic radiation (EMR) of ultra-high frequency (UHF), which can have a stimulating effect on metabolic and regenerative processes and strengthen the mechanisms of their regulation.Purpose of the study. To reveal the features of the effect of low-intensity microwave EMR/UHF on the development of adaptive metabolic and ultrastructural changes in the liver and blood of rats at an early stage of MS development. MATERIAL AND METHODS: The work was carried out on 40 nonlinear male rats weighing 180-220 g. In the experimental group, the rats were kept on a high-calorie diet for 2 months; in the control group, only the model was reproduced without the action of EMR/UHF; in the intact group, the animals were not exposed to any influences. The course of EMR/UHF (10 procedures) was carried out daily for 2 minutes on the lumbar region in the adrenal gland projection area using the Aquaton-2 device (power flux density less than 1 µW / cm2, frequency about 1000 MHz). The objects of the study were the liver and blood. Biochemical methods were used (RNA, DNA, total protein content, liver antioxidant activity, insulin and glucose levels in the blood), transmission electron microscopy, morphometric analysis of mitochondria (number, average and total area). RESULTS AND DISCUSSION: The use of low-intensity EMR/UHF at the background of the MS development caused an increase in a number of adaptive changes: the level of insulin in the blood increased; the content of total protein in the liver increased, and the severity of fatty degeneration decreased. The ultrastructural reorganization of hepatocytes was manifested in the activation of the protein synthesis apparatus (the phenomenon of hyperplasia of the granular endoplasmic reticulum, as well as ribosomes and polysomes). At the same time, the total area of mitochondria decreased, although their bioenergetic potential increased due to the condensation of the matrix. The revealed adaptive shifts were due to the antioxidant and membrane-stabilizing effects of EMR/UHF on general neuroendocrine and local mechanisms. CONCLUSION: Low-intensity EMR/UHF microwave can be a promising factor in the development of new methods of treatment and prevention of MS. In order to optimize the adaptive-protective and compensatory processes, as well as taking into account the decrease in the number of mitochondria, it is advisable to use EMR/UHF in more adequate modes.


Assuntos
Síndrome Metabólica , Animais , Carboidratos , Dieta , Radiação Eletromagnética , Fígado , Masculino , Síndrome Metabólica/etiologia , Ratos
5.
Medicine (Baltimore) ; 100(3): e23979, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33545984

RESUMO

ABSTRACT: Electromagnetic navigational bronchoscopy (ENB) combined with a radial endobronchial ultrasound probe realizes a combination of magnetic navigation and ultrasound imaging, allowing for the accurate navigation of peripheral lung lesions in real time during surgery. ENB has been evaluated in many studies. However, a comparative report on the feasibility of ENB combined radial endobronchial ultrasound diagnosis in different density lung nodules was small, and few of these studies have reported long-term follow-up results to exclude false negative results. The aim of this study is to explore the applicability of ENB combined radial endobronchial ultrasound in the diagnosis of lung nodules with different densities.Patients underwent biopsy in our medical center from 2016-09 to 2019-03 were divided into 2 groups: the solid nodule group and the subsolid pulmonary nodule group. We collected and analyzed the diagnostic accuracy, the diagnostic yield, the false negative rate and the incidence of complications between these 2 groups.A total of 37 lesions in 25 patients were biopsied, 14 lesions were subsolid pulmonary nodules and 23 were solid nodules. The diagnostic accuracy (success rate to obtain meaningful pathology tissues) was 34/37 (91.8%). Lost to follow-up in 1 case and three cases were undiagnosed. After at least 12 months of follow-up, the total diagnostic yield (true positive rate+ true negative rate) was 27/36 (75%) (P = .006). The false negative rate was 9/19 (47.3%) (P = .26). Complications occurred in 1/36 (2.7%) lesions. For the subsolid pulmonary nodule group, the diagnostic accuracy was 13/14 (92.8%) and the diagnostic yield was 7/14 (50%). For the solid nodule group, the diagnostic accuracy was 21/23 (91.3%), and the diagnostic yield was 20/22 (90.9%).Electromagnetic navigational bronchoscopy combined with radial endobronchial ultrasound in peripheral lung nodule biopsies is safe and effective, especially for solid nodules, but the diagnostic yield in subsolid nodule biopsies remains to be improved.


Assuntos
Broncoscopia/métodos , Pulmão/diagnóstico por imagem , Nódulo Pulmonar Solitário/diagnóstico por imagem , Ultrassonografia/métodos , Idoso , China , Radiação Eletromagnética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Nódulo Pulmonar Solitário/diagnóstico , Nódulo Pulmonar Solitário/fisiopatologia
6.
Nat Commun ; 12(1): 455, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469005

RESUMO

The technology of magnetic resonance imaging is developing towards higher magnetic fields to improve resolution and contrast. However, whole-body imaging at 7 T or even higher flux densities remains challenging due to wave interference, tissue inhomogeneities, and high RF power deposition. Nowadays, proper RF excitation of a human body in prostate and cardiac MRI is only possible to achieve by using phased arrays of antennas attached to the body (so-called surface coils). Due to safety concerns, the design of such coils aims at minimization of the local specific absorption rate (SAR), keeping the highest possible RF signal in the region of interest. Most previously demonstrated approaches were based on resonant structures such as e.g. dipoles, capacitively-loaded loops, TEM-line sections. In this study, we show that there is a better compromise between the transmit signal [Formula: see text] and the local SAR using non-resonant surface coils generating a low electric field in the proximity of their conductors. With this aim, we propose and experimentally demonstrate a leaky-wave antenna implemented as a periodically-slotted microstrip transmission line. Due to its non-resonant radiation, it induces only slightly over half the peak local SAR compared to a state-of-the-art dipole antenna but has the same transmit efficiency in prostate imaging at 7 T. Unlike other antennas for MRI, the leaky-wave antenna does not require to be tuned and matched when placed on a body, which makes it easy-to-use in prostate imaging at 7 T MRI.


Assuntos
Imagem por Ressonância Magnética/instrumentação , Imagem Corporal Total/instrumentação , Absorção de Radiação , Radiação Eletromagnética , Desenho de Equipamento , Humanos , Campos Magnéticos/efeitos adversos , Imagem por Ressonância Magnética/efeitos adversos , Imagem por Ressonância Magnética/métodos , Imagens de Fantasmas , Imagem Corporal Total/efeitos adversos , Imagem Corporal Total/métodos
7.
Neurosci Lett ; 744: 135587, 2021 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-33373676

RESUMO

The numerous factors regulate the bone marrow mesenchymal stem cell (BMMSC) self-renewal and differentiation response. We aimed to analyze the influence of electromagnetic field (EMF) as an external inducing factor on rat BMMSC differentiation and proliferation to neuron and astrocyte cells. BMMSCs extracted from the rats femurs and tibias and incubated in a cell-cultured CO2 incubator. After the third passages, the plates selected randomly and then divided into seven groups (Sham exposed, three groups of square, and three groups of sinusoidal waveform EMF (25, 50, and 75 Hz, 400 µT, 1 h/day). The BMMSCs exposed to EMF at the middle of a Helmholtz coil for 7 days. The viable cell counting and proliferation performed by the MTT test and BMMSC differentiation into the neuron and the astrocyte cell was studied by immunocytochemistry staining. The results confirmed BMMSC viability and proliferation rate reduction in sinusoidal 25 Hz, square 50 Hz and sinusoidal 75 Hz EMF groups compare to sham. The maximum BMMSC differentiation to neuron was considered in sinusoidal 50 Hz and 75 Hz EMF groups. The increase of BMMSC differentiation to astrocyte cell was frequency dependent and the most differentiation was shown in square 75 Hz, and sinusoidal 75 Hz EMF groups. In conclusion, the results suggest that both square and sinusoidal EMF could affect BMMSC development and differentiation to neuron and astrocyte cells. Further studies for the consequence of EMF with wider flux density and frequency on BMMSC are recommended.


Assuntos
Astrócitos/fisiologia , Diferenciação Celular/fisiologia , Radiação Eletromagnética , Células-Tronco Mesenquimais/fisiologia , Neurogênese/fisiologia , Animais , Sobrevivência Celular/fisiologia , Masculino , Ratos , Ratos Wistar
8.
Methods Mol Biol ; 2215: 309-319, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33368011

RESUMO

Microcrystal electron diffraction (MicroED) is a technique for structure determination that relies on the strong interaction of electrons with a minuscule, crystalline sample. While some of the electrons used to probe the crystal interact without altering the crystal, others deposit energy which changes the sample through a series of damage events. It follows that the sample cannot be observed without damaging it, and the frames obtained at the beginning of data collection reflect a crystal that differs from the one that yields the last frames of the dataset. Data acquisition at cryogenic temperatures has been found to reduce the rate of damage progression and is routinely used to increase the dose tolerance of the crystal, allowing more useful data to be obtained before the sample is destroyed. Low-dose data collection can further prolong the lifetime of the crystal, such that less damage is inflicted over the course of data acquisition. Ideally, lower doses increase the measurable volume of a single-crystal lattice by reducing the damage caused by probing electrons. However, the information that can be recovered from a diffraction image is directly related to the number of electrons used to probe the sample. The signal from a weakly exposed crystal runs the risk of being lost in the noise contributed by solvent, crystal disorder, and the electron detection process. This work focuses on obtaining the best possible data from a MicroED measurement, which requires considering several aspects such as sample, dose, and camera type.


Assuntos
Microscopia Crioeletrônica/métodos , Elétrons/efeitos adversos , Microscopia Eletrônica de Transmissão/métodos , Microscopia Crioeletrônica/normas , Radiação Eletromagnética , Microscopia Eletrônica de Transmissão/normas , Nanopartículas/química , Conformação Proteica
9.
Zhonghua Nan Ke Xue ; 26(10): 926-933, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33382226

RESUMO

Objective: To investigate the relationship of electromagnetic radiation (EMR) from 900 MHz cellphone frequency with testicular oxidative damage and its influence on the Prdx2 protein expression in the rat testis, and to explore the mechanism of Guilingji Capsules (GC) alleviating oxidative damage to the testis tissue. METHODS: Fifty healthy SD male rats were randomly divided into five groups of equal number, sham-EMR, 4-h EMR, 8-h EMR, 4-h EMR+GC and 8-h EMR+GC and exposed to 900 MHz EMR (370 µW/cm2) for 0, 4 or 8 hours daily for 15 successive days. The rats of the latter two groups were treated intragastrically with GC suspension and those of the first three groups with pure water after exposure to EMR each day. After 15 days of exposure and treatment, all the rats were sacrificed and their testis tissue collected for observation of the histomorphological and ultrastructural changes by HE staining and transmission electron microscopy, measurement of the levels of serum glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) with thiobarbiuric acid and determination of the Prdx2 protein expression by immunohistochemistry and Western blot. RESULTS: Compared with the rats in the sham-EMR group, those in the 4-h and 8-h EMR groups showed different degrees of histomorphological and ultrastructural changes in the testis tissue, significantly decreased levels of GSH (ï¼»80.62 ± 10.99ï¼½ vs ï¼»69.58 ± 4.18ï¼½ and ï¼»66.17 ± 8.45ï¼½ mg/L, P < 0.05) and SOD (ï¼»172.29 ± 10.98ï¼½ vs ï¼»158.92 ± 6.46ï¼½ and ï¼»148.91 ± 8.60ï¼½ U/ml, P < 0.05) and increased level of MDA (ï¼»7.51 ± 1.73ï¼½ vs ï¼»9.84 ± 1.03ï¼½ and ï¼»11.22 ± 2.13ï¼½ umol/ml, P < 0.05), even more significantly in the 8-h than in the 4-h EMR group (P < 0.05). In comparison with the sham-EMR group, the expression of the Prdx2 protein was markedly downregulated in the 4-h and 8-h EMR groups (0.56 ± 0.03 vs 0.49 ± 0.03, 0.21 ± 0.01, P < 0.05), but again upregulated in the 4-h and 8-h EMR+GC groups (0.55±0.03 and 0.37±0.04) (P < 0.05). CONCLUSIONS: Electromagnetic radiation from cellphones can cause ultrastructural damage to the testis tissue of male rats, while Guilingji Capsules can alleviate it, presumably by upregulating the Prdx2 protein expression in the testis tissue and reducing testicular oxidative damage.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Radiação Eletromagnética , Estresse Oxidativo , Peroxirredoxinas/metabolismo , Lesões Experimentais por Radiação/tratamento farmacológico , Testículo , Animais , Cápsulas , Telefone Celular , Glutationa/sangue , Masculino , Malondialdeído/sangue , Microscopia Eletrônica de Transmissão , Ratos , Superóxido Dismutase/sangue , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia , Substâncias Reativas com Ácido Tiobarbitúrico/análise
10.
Av. odontoestomatol ; 36(3): 152-159, sept.-dic. 2020. ilus, graf, tab
Artigo em Espanhol | IBECS | ID: ibc-197414

RESUMO

INTRODUCCIÓN: La correcta determinación de la Dimensión Vertical (DV) es esencial al momento de rehabilitar a un paciente. En la literatura existen escasas investigaciones que relacionen en conjunto la DV con otras variables como actividad electromiográfica.El objetivo de este estudio es describir una técnica para el análisis de la DVa través del Espacio Libre de Inoclusión (ELI), mediante la utilización de articulografíaelectromagnética y electromiografía de superficie. MATERIAL Y MÉTODOS: Se registró la DV mediante el uso de un articulógrafo electromagnético AG501 simultáneamente con la actividad electromiográfica de músculos masetero y temporal mediante la utilización de electromiógrafo de superficie EMG VIII, según protocolo de DVO y DVP.El estudio se realizó en el Laboratorio de Fisiología Oral del Centro de Investigación en Ciencias Odontológicas (CICO) con la Aprobación del Comité Ético Científico de la Universidad de La Frontera. RESULTADOS: Se obtuvo un protocolo para el uso de electromiografía y articulografía electromagnética 3D en el análisis de dimensión vertical, el cual permite caracterizar la dimensión vertical mediante una medición de distanciavertical, medición de distancia 3D, ángulo de apertura y la actividad eléctrica de los músculos elevadores de la mandíbula a distintos grados de apertura


INTRODUCTION: The correct determination of the Vertical Dimension (VD) is essential when rehabilitating a patient. There is little research in the literature that collectively relates the VD to other variables such as electromyographic activity. The objective of this study is to describe a technique for the analysis of the VD through the Interocclusal Distance, using electromagnetic articulography and surface electromyography. MATERIAL AND METHODS: The VD was recorded by using an AG501 electromagnetic articulgraph simultaneously with the electromyographic activity of masseter and temporal muscles using EMG VIII surface electromyograph, according to DVO and DVP protocol. The study was carried out in the Oral Physiology Laboratory of the Center for Research in Dental Sciences (CICO) with the approval of the Scientific Ethical Committee of the University of La Frontera. RESULTS: A protocol was obtained for the use of electromyography and 3D electromagnetic articulography in the vertical dimension analysis, which allows the vertical dimension to be characterized by a vertical distance measurement, 3D distance measurement, opening angle and the electrical activity of the lifting muscles of the jaw to different degrees of opening


Assuntos
Humanos , Eletromiografia/métodos , Dimensão Vertical , Radiação Eletromagnética , Mandíbula/diagnóstico por imagem , Protocolos Clínicos
11.
Ann Agric Environ Med ; 27(3): 427-434, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32955226

RESUMO

INTRODUCTION: The human body is constantly exposed to an extremely low electromagnetic field (ELF-EMF), in particular at 50 Hz, emitted by power lines, domestic distribution lines, electrical appliances, etc. It is assumed that the increase in electromagnetic exposure may cause adverse effects upon human health, as well as raising concerns regarding the impact on human fertility. OBJECTIVE: The aim of this in vitro study was to investigate the influence of ELF-EMF with a frequency of 50 Hz on the motility of human sperm. At the same time, the effectiveness of the dielectric screen constructed by ADR Technology ® in absorbing the emitted radiation was examined. MATERIAL AND METHODS: Semen samples of 20 patients were exposed to the influence of an extremely low electromagnetic field. After 5, 15 and 30 min., spermatozoa motility was analysed using a computer-assisted spermatozoa motility analysis system. The following sperm motility parameters were examined: 1) velocity straight linear motility; 2) cross-beat frequency; 3) lateral head displacement; 4) homogeneity of progressive motility velocity. RESULTS: It was found that the ELF-EMF presented a negative effect on the motility of human spermatozoa. A significant decrease in spermatozoa motility speed and a significant increase in lateral head deviation values were observed under the influence of the electromagnetic field. ELF-EMF did not show an effect on either lateral head displacement or homogeneity of progressive motility velocity. CONCLUSIONS: A positive effect of the dielectric screen ADR Technology® was found. This effect compensated spermatozoa motility changes induced with ELF-EMF.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Motilidade Espermática/efeitos da radiação , Espermatozoides/efeitos da radiação , Adulto , Radiação Eletromagnética , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Adulto Jovem
12.
Water Sci Technol ; 82(2): 373-385, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32941178

RESUMO

To evaluate the enhancing of the biological nitrogen removal effectiveness by electromagnetic wave loading on returned sludge in the A/A/O reactor, some experiments were completed with the returned sludge loaded by 2,450 MHz electromagnetic wave. The excess sludge yield and pollutant removal effect of the system were evaluated. Results showed that stronger denitrification effect and less sludge yield were achieved. When 30% of the returned sludge was loaded by electromagnetic wave, the actual denitrification efficiency increased by 7% without dosage. The dissolution of carbon, nitrogen and phosphorus from loaded returned sludge was detected, thus providing the system with a supplemental carbon source of 4.6 g/d SCOD. The specific oxygen uptake rate of the oxic activated sludge increased by 14%, and the denitrification rate of the anoxic activated sludge increased by 29%. Illumina MiSeq analysis showed that the microbial richness increased obviously, and denitrifying bacteria (i.e. Dechloromonas, Zoogloea and Azospira, etc.) were accumulated.


Assuntos
Nitrogênio , Esgotos , Anaerobiose , Reatores Biológicos , Desnitrificação , Radiação Eletromagnética , Fósforo , Eliminação de Resíduos Líquidos
13.
PLoS One ; 15(9): e0239667, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32986751

RESUMO

Life expectancy of contemporary cardiac pacemakers is limited due to the use of an internal primary battery. Repeated device replacement interventions are necessary, which leads to an elevated risk for patients and an increase of health care costs. The aim of our study is to investigate the feasibility of powering an endocardial pacemaker by converting a minimal amount of the heart's kinetic energy into electric energy. The intrinsic cardiac muscle activity makes it an ideal candidate as continuous source of energy for endocardial pacemakers. For this reason, we developed a prototype able to generate enough power to supply a pacing circuit at different heart rates. The prototype consists of a mass imbalance that drives an electromagnetic generator while oscillating. We developed a mathematical model to estimate the amount of energy harvested from the right ventricle. Finally, the implemented prototype was successfully tested during in-vitro and in-vivo experiments.


Assuntos
Fontes de Energia Elétrica , Radiação Eletromagnética , Endocárdio/fisiologia , Desenho de Equipamento , Modelos Teóricos , Marca-Passo Artificial , Animais , Velocidade do Fluxo Sanguíneo , Estudos de Viabilidade , Frequência Cardíaca , Suínos , Função Ventricular Direita/fisiologia
14.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(4): 302-306, 2020 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-32762201

RESUMO

Concerning on the safety risks caused by electromagnetic interference of patients implanted with high-risk active implantable medical devices in the environment of domestic MUs, this study evaluates and focuses on the requirements of electromagnetic compatibility in domestic and international standards for rail transit vehicles, the main mechanism of risks caused by EMI, the actual measurement of environmental data in MUs and the working performance of various active implantables in the compartment. The test results shows that all kinds of active implantable medical device samples works normally in the CRH2A EMU in China, and there is still a large margin between the measured radiation emission in MU and the limit required by the standards.


Assuntos
Campos Eletromagnéticos , China , Radiação Eletromagnética , Humanos , Marca-Passo Artificial , Próteses e Implantes
15.
Nat Commun ; 11(1): 3840, 2020 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-32737293

RESUMO

Currently, human magnetic resonance (MR) examinations are becoming highly specialized with a pre-defined and often relatively small target in the body. Conventionally, clinical MR equipment is designed to be universal that compromises its efficiency for small targets. Here, we present a concept for targeted clinical magnetic resonance imaging (MRI), which can be directly integrated into the existing clinical MR systems, and demonstrate its feasibility for breast imaging. The concept comprises spatial redistribution and passive focusing of the radiofrequency magnetic flux with the aid of an artificial resonator to maximize the efficiency of a conventional MR system for the area of interest. The approach offers the prospect of a targeted MRI and brings novel opportunities for high quality specialized MR examinations within any existing MR system.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Cerâmica/efeitos da radiação , Espectroscopia Dielétrica/métodos , Imagem por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Adulto , Cerâmica/química , Espectroscopia Dielétrica/instrumentação , Radiação Eletromagnética , Desenho de Equipamento , Feminino , Voluntários Saudáveis , Humanos , Imagem por Ressonância Magnética/instrumentação , Imagens de Fantasmas , Razão Sinal-Ruído
16.
Artigo em Inglês | MEDLINE | ID: mdl-32610554

RESUMO

Background: Electromagnetic pollution is a general health concern worldwide, as cell phone towers are ubiquitous and are located adjacent to or on the roof of schools, and hospitals. However, the health risks are still inconclusive. This cross-sectional study evaluated the potential effect of electromagnetic radiation generated from various resources including cell phone towers on blood glutathione S transferase activity (e-GST) and total antioxidant activity of the Jordanian population. Methods: The power density of three districts in the city of Irbid, Jordan was mapped to generate "outside the houses" and "inside the houses" maps. The effect of categorical variables (gender, using a cell phone, presence of Wi-Fi modem, previous exposure to medical imaging) and continuous variables (distance from the base station, the elevation of the house, the duration of stay in the house, power density outside houses, power density inside houses) on e-GST and total antioxidant activity were investigated. Results: The EMR generated outside the houses-including cell phone towers-did not reach inside the houses at the same power and had no significant influence on e-GST activity. The EMR inside the house, which primarily came from internal resources, has a significant effect on e-GST activity. The duration of stay inside the house, the use of cell phones, and the presence of a Wi-Fi modem had a proportional effect on e-GST activity. The total antioxidant activity was statistically equal between the tested and control groups. Conclusions: Several factors such as building materials restricted the penetration of EMR reaching inside the houses. EMR generated inside rather than outside the houses had a proportional effect on e-GST. The differences in e-GST were compensated successfully by other antioxidant mechanisms. Further research is needed to identify other possible sources of antioxidants, and to evaluate long-term effects and genetic polymorphism.


Assuntos
Telefone Celular , Radiação Eletromagnética , Estresse Oxidativo/fisiologia , Ondas de Rádio/efeitos adversos , Biomarcadores/metabolismo , Estudos Transversais , Feminino , Humanos , Jordânia , Masculino
17.
Eur. j. anat ; 24(4): 257-261, jul. 2020.
Artigo em Inglês | IBECS | ID: ibc-193956

RESUMO

The electromagnetic radiation from the mobile phone is a subject of recent study because of the enormous increase in mobile phone use through-out the world. The objective of this experiment was therefore to investigate the biochemical and histopathological effects of mobile phone radiation on male Swiss albino mice’s liver. Male mice were categorized into three groups in this research: control group (A), exposed group for 40 minutes (B) and exposed group for 60 minutes (C). Experimental groups were exposed to radiation per day for 60 days from 4G connected mobile phones. The control group received no radiation. At the end of the radiation exposure, biochemical (alanine transaminase (ALT) and aspartate transaminase (AST)) and histological tests were performed. The results indicated that there was significant (P < 0.05) increase in mean values of ALT and AST in both radiation-exposed groups of mice if com-pared to the control group. Histopathologically marked infiltration of mononuclear cellular aggregates were present surrounding the bile duct and hepatic artery in the liver of 60-minute-exposure group, whereas in 40-minute-exposure group con-gestion was observed in the portal vein and the central vein of the liver. The findings revealed and evidenced that mobile phone radiation has harmful effects on enzyme activity and liver tis


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Assuntos
Animais , Masculino , Camundongos , Fígado/efeitos da radiação , Fígado/patologia , Telefone Celular , Radiação Eletromagnética , Exposição à Radiação/efeitos adversos , Alanina Transaminase/efeitos da radiação , Modelos Animais , Alanina Transaminase/análise , Aspartato Aminotransferases/efeitos da radiação
18.
Middle East Afr J Ophthalmol ; 27(1): 10-13, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32549718

RESUMO

PURPOSE: The aim of this study is to investigate the effects of electromagnetic waves (EMWs) emitted by a mobile phone on the intraocular pressure (IOP) in the eyeball. METHODS: This quasi-experimental study was conducted on 166 eyes from 83 individuals in the 40-70 age range who referred to "Khatam-al-Anbia Hospital, Mashhad, Iran" in 2016. There were two groups of participants, and the first one consisted of 41 participants who had normal eyes, whereas the second one comprised 42 participants who suffered from open-angle glaucoma disease. The IOP in both groups was measured and recorded by a specialist before and after talking 5 min on the cellphone with the help of the Goldman method. Statistical analysis such as paired t-test and analysis of variance was performed and all tests are statistically significant at (P < 0.05). For this purpose, the SPSS software (version 16) was applied. RESULTS: IOP in the glaucoma eye (42 eyes) ipsilateral to mobile phone before and after the intervention was 18.64 ± 6.7 and 23.53 ± 6.3, respectively (P < 0.001). However, IOP in the control group (41 eyes) ipsilateral to mobile phone before and after the intervention was 12.95 ± 3.5 and 13.39 ± 2.8, respectively (P = 0.063). IOP change in the opposite glaucomatous eye to mobile phone in glaucoma group (39 eyes) and normal group (44 eyes) was not significantly different before and after the phone call (P = 0.065 and P = 0.85, respectively). CONCLUSION: We found that the acute effects of EMWs emitted from the mobile phones can significantly increase the IOP in glaucoma eye, while such changes were not observed in normal eyes.


Assuntos
Telefone Celular/instrumentação , Campos Eletromagnéticos/efeitos adversos , Radiação Eletromagnética , Glaucoma de Ângulo Aberto/etiologia , Pressão Intraocular/efeitos da radiação , Adulto , Idoso , Feminino , Glaucoma de Ângulo Aberto/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Tonometria Ocular
19.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(1): 77-81, 2020 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-32476377

RESUMO

OBJECTIVE: To evaluate the effects of prenatal radiation of 850~1 900 MHz mobile phone on white matter in cerebellum of adult rat offspring. METHODS: Pregnant rats were randomly divided into short term maternal radiation group, long term maternal radiation group and control group. Rats in short term and long term maternal radiation group were exposed to 6 h/d and 24 h/d mobile phone radiation during 1-17 days of pregnancy, respectively. The cerebellums of offspring rats at the age of 3 month(n=8)were taken. Cell morphology in cerebellum was studied by hematoxylin-eosin (HE) staining. The expressions of myelin basic protein (MBP), neurofilament-L (NF-L) and glial fibrillary acidic protein (GFAP) in cerebellum of rat offspring were detected by immunohistochemistry and Western blot. RESULTS: Compared to control group, the morphological changes of purkinje cells in cerebellum were obvious in rat offspring of short term and long term maternal radiation group. Compared to control group, decreased MBP and NF-L expressions and increased GFAP expression were observed in long term maternal radiation group(all P<0.05). Compared to short term radiation group, the expressions of MBP and NF-L were down-regulated (all P<0.05) and the expression of GFAP was up- regulated(P<0.05) in long term radiation group. CONCLUSION: Prenatal mobile phone radiation might lead to the damage of myelin and axon with activity of astrocytes in cerebellum of male rat offspring, which is related to the extent of radiation.


Assuntos
Telefone Celular , Cerebelo/efeitos da radiação , Radiação Eletromagnética , Efeitos Tardios da Exposição Pré-Natal , Substância Branca/efeitos da radiação , Animais , Cerebelo/patologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Masculino , Proteína Básica da Mielina/metabolismo , Proteínas de Neurofilamentos/metabolismo , Gravidez , Distribuição Aleatória , Ratos , Substância Branca/patologia
20.
Nat Methods ; 17(7): 681-684, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32451477

RESUMO

Time-resolved crystallography with X-ray free-electron lasers enables structural characterization of light-induced reactions on ultrafast timescales. To be biologically and chemically relevant, such studies must be carried out in an appropriate photoexcitation regime to avoid multiphoton artifacts, a common issue in recent studies. We describe numerical and experimental approaches to determine how many photons are needed for single-photon excitation in microcrystals, taking into account losses by scattering.


Assuntos
Cristalografia por Raios X/métodos , Fótons , Radiação Eletromagnética , Lasers , Luz , Espalhamento de Radiação
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