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1.
Arq Neuropsiquiatr ; 79(2): 139-148, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33759981

RESUMO

BACKGROUND: The use of technological devices is growing rapidly, and the use of cell phones increases in parallel. Dependence on technological devices is a particular factor in this increased exposure. Many studies have been performed on this electromagnetic field, but no definite conclusions have been drawn. OBJECTIVE: The purpose of this research was to investigate exposure to electromagnetic field, cell phone use behaviors, the specific absorption rate (SAR) values, and changes in health occurring after exposure in university students. METHODS: A questionnaire was administered to 1,019 volunteer students aged 18-24 years at the Nigde Ömer Halisdemir and Recep Tayip Erdogan Universities in 2018-2019. The questions were based on a survey of the literature. RESULTS: The students spent an average 4-8 hours per day on their cell phones, and findings such as headache (p=0.002), concentration deficit (p=0.001), tiredness on waking in the morning (p=0.001), hyperactivity (p=0.001), general feeling of fatigue (p=0.001), and lethargy (p=0.001) increased in a statistically significant manner with length of use. CONCLUSIONS: Participants exhibited high levels of cell phone use and experienced biological, behavioral, and sleep problems. They also had very little knowledge about specific SAR values, an important criterion concerning cell phones.


Assuntos
Uso do Telefone Celular , Telefone Celular , Adolescente , Adulto , Campos Eletromagnéticos/efeitos adversos , Humanos , Estudantes , Universidades , Adulto Jovem
2.
PLoS One ; 16(3): e0245900, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33711025

RESUMO

The coronavirus pandemic has seen a marked rise in medical disinformation across social media. A variety of claims have garnered considerable traction, including the assertion that COVID is a hoax or deliberately manufactured, that 5G frequency radiation causes coronavirus, and that the pandemic is a ruse by big pharmaceutical companies to profiteer off a vaccine. An estimated 30% of some populations subscribe some form of COVID medico-scientific conspiracy narratives, with detrimental impacts for themselves and others. Consequently, exposing the lack of veracity of these claims is of considerable importance. Previous work has demonstrated that historical medical and scientific conspiracies are highly unlikely to be sustainable. In this article, an expanded model for a hypothetical en masse COVID conspiracy is derived. Analysis suggests that even under ideal circumstances for conspirators, commonly encountered conspiratorial claims are highly unlikely to endure, and would quickly be exposed. This work also explores the spectrum of medico-scientific acceptance, motivations behind propagation of falsehoods, and the urgent need for the medical and scientific community to anticipate and counter the emergence of falsehoods.


Assuntos
/patologia , Decepção , /virologia , Campos Eletromagnéticos , Fraude/estatística & dados numéricos , Humanos , Revelação da Verdade , Vacinação , Tecnologia sem Fio
3.
Carbohydr Polym ; 260: 117840, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712175

RESUMO

Highly efficient shielding materials with an excellent electromagnetic wave absorption have gained increased attention. A new design was used to provide cellulose paper with a high electromagnetic shielding effectiveness (EMI SE) and improve the absorption performance by constructing an asymmetry sandwich structure that consisted of a dense nickel coating, Fe3O4 nanoparticles and a porous nickel layer. This unique structure caused a "multiple reflection-absorb-reflection" process when the electromagnetic waves penetrated the sample. The EMI absorption (SEA) and total SE (SET) increased with Fe3O4 absorption time increasing at 8.2-12.4 GHz, which was attributed to the synergistic effect between porous nickel layer and Fe3O4 nanoparticles. The SEA and SET of the sample with a thickness of 0.195 mm can achieved 18.57 and 41.88 dB, respectively. The design was conducive to improving the magnetic and corrosion resistance properties. This study provided a novel path to obtain a low cost and lightweight electromagnetic shielding material that can reduce secondary radiation.


Assuntos
Celulose/química , Óxido Ferroso-Férrico/química , Níquel/química , Protetores contra Radiação/química , Condutividade Elétrica , Campos Eletromagnéticos , Magnetismo , Nanopartículas Metálicas/química , Porosidade , Propriedades de Superfície , Temperatura
4.
Molecules ; 26(4)2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33671776

RESUMO

A theoretical evaluation of the electric Freedericksz transition threshold and saturation field is proposed for a liquid crystals composite with ferroelectric particles. Existing models consider a strong anchoring of nematic molecules on the glass support of the cell, but in this paper a soft molecular anchoring of molecules on the glass support and also on the ferroelectric nanoparticle's surface is assumed. Thus, a finite saturation field was obtained in agreement with real systems. Calculations are made for planar configuration of positive dielectric anisotropy liquid crystals. The results are compared with data obtained on similar systems from different publications and the differences are discussed.


Assuntos
Cristais Líquidos/química , Simulação de Dinâmica Molecular , Campos Eletromagnéticos , Nanopartículas/química , Tamanho da Partícula , Propriedades de Superfície
5.
Molecules ; 26(4)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33672380

RESUMO

In the present study, a sunflower-like nanostructure array composed of a series of synaptic nanoparticles and nanospheres was manufactured through an efficient and low-cost colloidal lithography technique. The primary electromagnetic field contribution generated by the synaptic nanoparticles of the surface array structures was also determined by a finite-difference time-domain software to simulate the hotspots. This structure exhibited high repeatability and excellent sensitivity; hence, it was used as a surface-enhanced Raman spectroscopy (SERS) active substrate to achieve a rapid detection of ultra-low concentrations of Alpha-fetoprotein (AFP). This study demonstrates the design of a plasmonic structure with strong electromagnetic coupling, which can be used for the rapid detection of AFP concentration in clinical medicine.


Assuntos
Nanoestruturas/química , alfa-Fetoproteínas/análise , Coloides/química , Campos Eletromagnéticos , Tamanho da Partícula , Software , Análise Espectral Raman , Propriedades de Superfície
6.
Artigo em Inglês | MEDLINE | ID: mdl-33530365

RESUMO

The recent development of millimeter-wave (mmW) technologies, such as the fifth-generation (5G) network, comes with concerns related to user exposure. A quite large number of dosimetry studies above 6 GHz have been conducted, with the main purpose being to establish the correlation between different dosimetric parameters and the skin surface temperature elevation. However, the dosimetric studies from 28 GHz user equipment using different voxel models have not been comprehensively discussed yet. In this study, we used the finite-difference time-domain (FDTD) method for the estimation of the absorption of radiofrequency (RF) energy from a microstrip patch antenna array (28 GHz) in different human models. Specifically, we analyzed different exposure conditions simulating three real common scenarios (a phone call scenario, message writing scenario, and browsing scenario) regarding the use of smartphones/tablets by four different individuals (adult male and female, child male and female). From the results of Absorbed Power Density (Sab), it is possible to conclude that all the considered exposure scenarios comply with the safety limits, both for adult and children models. However, the high values of the local Specific Absorption Rate (SAR) in the superficial tissues and the slight differences in its distribution between adults and children suggest the need for further and more detailed analysis.


Assuntos
Campos Eletromagnéticos , Ondas de Rádio , Adulto , Criança , Campos Eletromagnéticos/efeitos adversos , Feminino , Humanos , Masculino , Ondas de Rádio/efeitos adversos , Radiometria
7.
Artigo em Inglês | MEDLINE | ID: mdl-33573059

RESUMO

BACKGROUND: this study aims to estimate the rate of death by cancer as a result of Radio Base Station (RBS) radiofrequency exposure, especially for breast, cervix, lung, and esophagus cancers. METHODS: we collected information on the number of deaths by cancer, gender, age group, gross domestic product per capita, death year, and the amount of exposure over a lifetime. We investigated all cancer types and some specific types (breast, cervix, lung, and esophagus cancers). RESULTS: in capitals where RBS radiofrequency exposure was higher than 2000/antennas-year, the average mortality rate was 112/100,000 for all cancers. The adjusted analysis showed that, the higher the exposure to RBS radiofrequency, the higher cancer mortality was. The highest adjusted risk was observed for cervix cancer (rate ratio = 2.18). The spatial analysis showed that the highest RBS radiofrequency exposure was observed in a city in southern Brazil that also showed the highest mortality rate for all types of cancer and specifically for lung and breast cancer. CONCLUSION: the balance of our results indicates that exposure to radiofrequency electromagnetic fields from RBS increases the rate of death for all types of cancer.


Assuntos
Telefone Celular , Neoplasias , Brasil/epidemiologia , Cidades , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental/efeitos adversos , Feminino , Humanos , Ondas de Rádio/efeitos adversos
8.
ACS Appl Mater Interfaces ; 13(7): 8049-8059, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33570931

RESUMO

Label-free optical detection of biomolecules is currently limited by a lack of specificity rather than sensitivity. To exploit the much more characteristic refractive index dispersion in the mid-infrared (IR) regime, we have engineered three-dimensional IR-resonant silicon micropillar arrays (Si-MPAs) for protein sensing. By exploiting the unique hierarchical nano- and microstructured design of these Si-MPAs attained by CMOS-compatible silicon-based microfabrication processes, we achieved an optimized interrogation of surface protein binding. Based on spatially resolved surface functionalization, we demonstrate controlled three-dimensional interfacing of mammalian cells with Si-MPAs. Spatially controlled surface functionalization for site-specific protein immobilization enabled efficient targeting of soluble and membrane proteins into sensing hotspots directly from cells cultured on Si-MPAs. Protein binding to Si-MPA hotspots at submonolayer level was unambiguously detected by conventional Fourier transform IR spectroscopy. The compatibility with cost-effective CMOS-based microfabrication techniques readily allows integration of this novel IR transducer into fully fledged bioanalytical microdevices for selective and sensitive protein sensing.


Assuntos
Técnicas Biossensoriais , Proteínas de Fluorescência Verde/isolamento & purificação , Análise Serial de Proteínas , Silício/química , Campos Eletromagnéticos , Proteínas de Fluorescência Verde/química , Células HeLa , Humanos , Imagem Óptica , Tamanho da Partícula , Propriedades de Superfície , Células Tumorais Cultivadas
9.
Artigo em Russo | MEDLINE | ID: mdl-33580764

RESUMO

OBJECTIVE: To test the hypothesis that weak electromagnetic fields of low frequencies (0.5-26 Hz) could affect daytime sleep features and structure. MATERIAL AND METHODS: Parameters of daytime sleep continuity were compared in the study with counterbalanced control/exposition (40 min exposure to electromagnetic field at 1 Hz/0.004 µT) scheme in 22 healthy volunteers. Nonlinear regression model was used to assess daytime sleep continuity. RESULTS: Exposure to a weak electromagnetic field of ultra-low frequency significantly improved the quality of sleep, assessed by the indicator of sleep continuity, namely, there were fewer transitions from the second and deeper stages of sleep to the first stage and to the state of wakefulness (p<0.0001). CONCLUSION: The results can be used to develop non-pharmacological methods of sleep correction, as well as to improve the quality of short-term sleep and its positive effect on well-being, cognitive function and working capacity.


Assuntos
Campos Eletromagnéticos , Fragilidade , Cognição , Humanos , Sono , Vigília
10.
Neuroimage ; 228: 117696, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33385544

RESUMO

BACKGROUND: During transcranial magnetic stimulation (TMS) a coil placed on the scalp is used to non-invasively modulate activity of targeted brain networks via a magnetically induced electric field (E-field). Ideally, the E-field induced during TMS is concentrated on a targeted cortical region of interest (ROI). Determination of the coil position and orientation that best achieve this objective presently requires a large computational effort. OBJECTIVE: To improve the accuracy of TMS we have developed a fast computational auxiliary dipole method (ADM) for determining the optimum coil position and orientation. The optimum coil placement maximizes the E-field along a predetermined direction or, alternatively, the overall E-field magnitude in the targeted ROI. Furthermore, ADM can assess E-field uncertainty resulting from precision limitations of TMS coil placement protocols. METHOD: ADM leverages the electromagnetic reciprocity principle to compute rapidly the TMS induced E-field in the ROI by using the E-field generated by a virtual constant current source residing in the ROI. The framework starts by solving for the conduction currents resulting from this ROI current source. Then, it rapidly determines the average E-field induced in the ROI for each coil position by using the conduction currents and a fast-multipole method. To further speed-up the computations, the coil is approximated using auxiliary dipoles enabling it to represent all coil orientations for a given coil position with less than 600 dipoles. RESULTS: Using ADM, the E-fields generated in an MRI-derived head model when the coil is placed at 5900 different scalp positions and 360 coil orientations per position (over 2.1 million unique configurations) can be determined in under 15 min on a standard laptop computer. This enables rapid extraction of the optimum coil position and orientation as well as the E-field variation resulting from coil positioning uncertainty. ADM is implemented in SimNIBS 3.2. CONCLUSION: ADM enables the rapid determination of coil placement that maximizes E-field delivery to a specific brain target. This method can find the optimum coil placement in under 15 min enabling its routine use for TMS. Furthermore, it enables the fast quantification of uncertainty in the induced E-field due to limited precision of TMS coil placement protocols, enabling minimization and statistical analysis of the E-field dose variability.


Assuntos
Simulação por Computador , Estimulação Magnética Transcraniana/métodos , Campos Eletromagnéticos , Humanos , Modelos Anatômicos
11.
Med Hypotheses ; 147: 110487, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33465563

RESUMO

Several studies point to the antimicrobial effects of ELF electromagnetic fields. Such fields have accompanied life from the very beginning, and it is possible that they played a significant role in its emergence and evolution. However, the literature on the biological effects of ELF electromagnetic fields is controversial, and we still lack an understanding of the complex mechanisms that make such effects, observed in many experiments, possible. The Covid-19 pandemic has shown how fragile we are in the face of powerful processes operating in the biosphere. We believe that understanding the role of ELF electromagnetic fields in regulating the biosphere is important in our fight against Covid-19, and research in this direction should be intensified.


Assuntos
/epidemiologia , Campos Eletromagnéticos , Atividade Solar , /etiologia , Humanos , Modelos Teóricos , Pandemias
12.
Methods Mol Biol ; 2217: 197-233, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33215383

RESUMO

Integrins are stress-sensing proteins expressed on the surface of cells. They regulate bidirectional signal transduction during cell-cell or cell-extracellular matrix (ECM) contacts. Integrins link the ECM with the cytoplasm through interaction with their ligands. Biophysically, such interactions can be understood as changes in stress fields at specific integrin stress-sensing domains, such as the MIDAS and ADMIDAS domains. Stress changes between ligands and cytoskeletal structures are involved in cancer cell growth by altering signal transduction pathways dependent on integrin activation. In this chapter, previous results regarding integrin activation and tumor cell growth using nanoparticles (NPs) of different materials, sizes and shapes are placed within a framework of polarized NPs in the ECM by external electromagnetic fields, in which the synergic action between polarized NPs and electromagnetic fields activates the integrins. Small size NPs activate integrins via the polar component of the dipole force between NPs and integrin sensing stress sites, while large size NPs exercise a similar action via the radial component. A quantum electrodynamic model also accounts for ECM overstressing by electromagnetic mode trapping between coherent symmetric and antisymmetric quantum states.


Assuntos
Citoesqueleto/química , Campos Eletromagnéticos , Matriz Extracelular/química , Integrinas/química , Nanopartículas/química , Células A549 , Animais , Sítios de Ligação , Adesão Celular , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Matriz Extracelular/metabolismo , Matriz Extracelular/ultraestrutura , Humanos , Integrinas/agonistas , Integrinas/metabolismo , Integrinas/ultraestrutura , Ligantes , Células MCF-7 , Mecanotransdução Celular , Microscopia de Força Atômica/métodos , Nanopartículas/metabolismo , Nanopartículas/ultraestrutura , Tamanho da Partícula , Ligação Proteica , Teoria Quântica , Termodinâmica
13.
Carbohydr Polym ; 254: 117033, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357838

RESUMO

Electromagnetic-interference (EMI) shielding materials that are green, lightweight, and with high mechanical properties need to be urgently developed to address increasingly severe radiation pollution. However, limited EMI shielding materials are successfully used in practical applications, due to the intensive energy consumption or the absence of sufficient strength. Herein, an environmentally friendly and effective method was proved to fabricate wood-based composites with high mechanical robustness and EMI shielding performance by a MXene/cellulose scaffold assembly strategy. The lignocellulose composites with a millimeter-thick mimic the "mortar-brick" layered structure, resulting in excellent mechanical properties that can achieve the compressive strength of 288 MPa and EMI shielding effectiveness of 39.3 dB. This "top-down" method provides an alternative for the efficient production of robust and sustainable EMI shielding materials that can be used in the fields of structural materials for next-generation communications and electronic devices.


Assuntos
Celulose/química , Proteção Radiológica/instrumentação , Madeira/química , Celulose/ultraestrutura , Força Compressiva , Módulo de Elasticidade , Condutividade Elétrica , Campos Eletromagnéticos , Lignina/química , Lignina/ultraestrutura , Ciência dos Materiais , Teste de Materiais , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Varredura , Nanocompostos/química , Nanocompostos/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Madeira/ultraestrutura
14.
Chemosphere ; 262: 127698, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32791365

RESUMO

The influence of electromagnetic fields on bacterial denitrification has been tested on synthetic media with sludges from wastewater treatment stations, in batch mode. The effects of the intensity of the magnetic induction ratio B (mT), reaction volume and initial biomass concentration on the kinetics of the denitrification process were studied. Magnetic field had both an optimal stimulating effect on the activity of the denitrifying flora for B (mT)/mgx values of the order of 0.212, and an inhibitory effect for the values beyond the latter.Sludges underwent multiple exposure cycles to magnetic fields. It was shown that, after three exposure cycles, denitrification kinetics went from 6.5 to 12.7 mg N-NO-3.L-1.h-1 which corresponds to a 2.7 fold improvement. The improved performance persists even after the cessation of the magnetic field. Observation of the sludge by the environmentalelectron microscope shows that the microbial population forming the starting sludge; changed following exposure to the magnetic field. The action of the; electromagnetic field on the microbial populations in denitrification resulted in the modification of the diversity of the flora that is initially present, favoring the development of Proteo bacteria, particularly the Betaproteo bacteria subclass, which results in improved denitrification.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Bactérias , Biomassa , Reatores Biológicos/microbiologia , Desnitrificação , Campos Eletromagnéticos , Campos Magnéticos , Nitrogênio/análise , Esgotos/microbiologia , Águas Residuárias
15.
Sensors (Basel) ; 20(24)2020 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-33322725

RESUMO

The aim of this study was to evaluate the absorption in a user's head of an electromagnetic field (EMF) emitted by the Wi-Fi and/or Bluetooth module of a wearable small Internet of Things (IoT) electronic device (emitting EMF of up to 100 mW), in order to test the hypothesis that EMF has an insignificant influence on humans, and to compare the levels of such EMF absorption in various scenarios when using this device. The modelled EMF source was a meandered inverted-F antenna (MIFA)-type antenna of the ESP32-WROOM-32 radio module used in wearable devices developed within the reported study. To quantify the EMF absorption, the specific energy absorption rate (SAR) values were calculated in a multi-layer ellipsoidal model of the human head (involving skin, fat, skull bones and brain layers). The obtained results show up to 10 times higher values of SAR from the MIFA located in the headband, in comparison to its location on the helmet. Only wearable IoT devices (similar in construction and way of use to the investigated device) emitting at below 3 mW equivalent isotropically radiated power (EIRP) from Wi-Fi/Bluetooth communications modules may be considered environmentally insignificant EMF sources.


Assuntos
Campos Eletromagnéticos , Dispositivos Eletrônicos Vestíveis , Cabeça , Humanos , Internet , Local de Trabalho
16.
PLoS One ; 15(12): e0244738, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33382855

RESUMO

Utilization of metal-oxide nanoparticles (NPs) in enhanced oil recovery (EOR) has generated substantial recent research interest in this area. Among these NPs, zinc oxide nanoparticles (ZnO-NPs) have demonstrated promising results in improving oil recovery due to their prominent thermal properties. These nanoparticles can also be polarized by electromagnetic (EM) field, which offers a unique Nano-EOR approach called EM-assisted Nano-EOR. However, the impact of NPs concentrations on oil recovery mechanism under EM field has not been well established. For this purpose, ZnO nanofluids (ZnO-NFs) of two different particle sizes (55.7 and 117.1 nm) were formed by dispersing NPs between 0.01 wt.% to 0.1 wt.% in a basefluid of sodium dodecylbenzenesulfonate (SDBS) and NaCl to study their effect on oil recovery mechanism under the electromagnetic field. This mechanism involved parameters, including mobility ratio, interfacial tension (IFT) and wettability. The displacement tests were conducted in water-wet sandpacks at 95˚C, by employing crude oil from Tapis. Three tertiary recovery scenarios have been performed, including (i) SDBS surfactant flooding as a reference, (ii) ZnO-NFs flooding, and (iii) EM-assisted ZnO-NFs flooding. Compare with incremental oil recovery from surfactant flooding (2.1% original oil in place/OOIP), nanofluid flooding reaches up to 10.2% of OOIP at optimal 0.1 wt.% ZnO (55.7 nm). Meanwhile, EM-assisted nanofluid flooding at 0.1 wt.% ZnO provides a maximum oil recovery of 10.39% and 13.08% of OOIP under EM frequency of 18.8 and 167 MHz, respectively. By assessing the IFT/contact angle and mobility ratio, the optimal NPs concentration to achieve a favorable ER effect and interfacial disturbance is determined, correlated to smaller hydrodynamic-sized nanoparticles that cause strong electrostatic repulsion between particles.


Assuntos
Nanopartículas Metálicas , Indústria de Petróleo e Gás , Óxido de Zinco , Campos Eletromagnéticos , Tensão Superficial
17.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 3537-3543, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018767

RESUMO

In this study, we present a temporal interference (TI) concept to achieve focal and steerable stimulation in the targeted brain area through transcranial magnetic stimulation (TMS). This method works by inducing two high-frequency electric fields with a slight frequency difference via two independent coils. The intrinsic nonlinear nature of the nerve membrane, which acts as a low-pass filter, does not allow the nerve to engage at high frequencies. Instead, neurons at the intersection of two electric fields can follow the frequency difference of the two fields. For 3D MRI-derived head models, the finite element method is used to compute the electric field induced by the time-varying magnetic field along with the electric field penetration depth and the activated volume for the specific coil parameters. A deeper stimulation with an acceptable spatial spread can be obtained by controlling the intersection of the fields by finding the optimal position and orientation of the two coils. Moreover, by changing the voltage ratio of the coils, and not their mechanical orientation, the intended area can be dynamically driven. The computational results show that the TI technique is an efficient approach to resolve the electric field depth-focality trade-off, which can be a reasonable alternative to complex coil designs. The system proposed in this paper shows a great promise for a more dynamic and focused magnetic stimulation.


Assuntos
Encéfalo , Estimulação Magnética Transcraniana , Eletricidade , Campos Eletromagnéticos , Campos Magnéticos
18.
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
19.
Pediatrics ; 146(4)2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32994178

RESUMO

BACKGROUND AND OBJECTIVES: Postpyloric feeding tube placement is a time-consuming procedure associated with multiple attempts and radiation exposure. Our objective with this study is to compare the time, attempts, and radiation exposure using the electromagnetic versus blind method to place a postpyloric feeding tube in critically ill children. Our hypothesis is that using electromagnetic guidance decreases the procedure time, number of x-rays, and number of attempts, compared to the blind method. METHODS: Eleven pediatric nurses participated in a randomized controlled intention-to-treat study at an academic pediatric medical, surgical, and congenital cardiac ICU. University of Texas Health Epidemiology and Biostatistics generated a randomization sequence with sealed envelopes. A standard (2-sided) F-test of association between the electromagnetic and blind method yielded 40 subjects with 86% power. Data were analyzed with Fisher's exact test for categorical variables and the Wilcoxon rank test for continuous variables, with data documented as median (interquartile range [IQR]). RESULTS: We randomly assigned 52 patients to either the electromagnetic (n = 28) or blind method (n = 24). The number of attempts and radiographs was at a median of 2 (IQR: 1-2.25) using the blind method, compared to the electromagnetic method at a median of 1 (IQR: 1.0-1.0; P = .001). Successful guidance was 96.4% with the electromagnetic method, compared to only 66.7% with the blind technique (P = .008). The total time required was 2.5 minutes (IQR: 2.0-7.25) with the electromagnetic method, compared to 19 minutes (IQR: 9.25-27.0) for the blind method (P = .001). CONCLUSIONS: Electromagnetic guidance is a superior, faster, and overall safer method to place a postpyloric feeding tube in critically ill children.


Assuntos
Intubação Gastrointestinal/métodos , Imãs , Piloro , Adolescente , Adulto , Criança , Pré-Escolar , Estado Terminal , Campos Eletromagnéticos , Nutrição Enteral/métodos , Feminino , Humanos , Análise de Intenção de Tratamento , Intubação Gastrointestinal/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Piloro/diagnóstico por imagem , Exposição à Radiação/prevenção & controle , Radiografia Abdominal/estatística & dados numéricos , Estatísticas não Paramétricas , Fatores de Tempo , Adulto Jovem
20.
Biomed Environ Sci ; 33(8): 593-602, 2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32933611

RESUMO

Objective: This study aimed to investigate the effect of exposure to a 900 MHz electromagnetic field (EMF) on the cervical spinal cord (CSC) of rats and the possible protective effect of luteolin (LUT) against CSC tissue damage. Methods: Quantitative data were obtained via stereological, biochemical, immunohistochemical, and histopathological techniques. We investigated morphometric value, superoxide dismutase (SOD) level, and the expression of high-mobility group box 1 protein molecules, as well as histological changes. Results: The total number of motor neurons in the EMF group significantly decreased in comparison with that in the control group ( P < 0.05). In the EMF + LUT group, we found a significant increase in the total number of motor neurons compared with that in the EMF group ( P < 0.05). SOD enzyme activity in the EMF group significantly increased in comparison with that in the control group ( P < 0.05). By contrast, the EMF+LUT group exhibited a decrease in SOD level compared with the EMF group ( P < 0.05). Conclusion: Our results suggested that exposure to EMF could be deleterious to CSC tissues. Furthermore, the protective efficacy of LUT against SC damage might have resulted from the alleviation of oxidative stress caused by EMF.


Assuntos
Antioxidantes/farmacologia , Campos Eletromagnéticos/efeitos adversos , Luteolina/farmacologia , Medula Espinal/efeitos dos fármacos , Medula Espinal/efeitos da radiação , Animais , Masculino , Ratos , Ratos Wistar
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