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1.
Environ Pollut ; 294: 118646, 2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-34896224

RESUMO

With the rapidly increasing popularity of 5G mobile technology, the effect of radiofrequency radiation on human health has caused public concern. This study explores the effects of a simulated 3.5 GHz radiofrequency electromagnetic radiation (RF-EMF) environment on the development and microbiome of flies under intensities of 0.1 W/m2, 1 W/m2 and 10 W/m2. We found that the pupation percentages in the first 3 days and eclosion rate in the first 2 days were increased under exposure to RF-EMF, and the mean development time was shortened. In a study on third-instar larvae, the expression levels of the heat shock protein genes hsp22, hsp26 and hsp70 and humoral immune system genes AttC, TotC and TotA were all significantly increased. In the oxidative stress system, DuoX gene expression was decreased, sod2 and cat gene expression levels were increased, and SOD and CAT enzyme activity also showed a significant increase. According to the 16S rDNA results, the diversity and species abundance of the microbial community decreased significantly, and according to the functional prediction analysis, the genera Acetobacter and Lactobacillus were significantly increased. In conclusion, 3.5 GHz RF-EMF may enhance thermal stress, oxidative stress and humoral immunity, cause changes in the microbial community, and regulate the insulin/TOR and ecdysteroid signalling pathways to promote fly development.


Assuntos
Drosophila melanogaster , Campos Eletromagnéticos , Microbiota/efeitos da radiação , Ondas de Rádio , Animais , Telefone Celular , Drosophila melanogaster/embriologia , Drosophila melanogaster/microbiologia , Drosophila melanogaster/efeitos da radiação , Expressão Gênica , Proteínas de Choque Térmico , Larva/efeitos da radiação
2.
Sensors (Basel) ; 21(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34960513

RESUMO

The densification of multiple wireless communication systems that coexist nowadays, as well as the 5G new generation cellular systems advent towards the millimeter wave (mmWave) frequency range, give rise to complex context-aware scenarios with high-node density heterogeneous networks. In this work, a radiofrequency electromagnetic field (RF-EMF) exposure assessment from an empirical and modeling approach for a large, complex indoor setting with high node density and traffic is presented. For that purpose, an intensive and comprehensive in-depth RF-EMF E-field characterization study is provided in a public library study case, considering dense personal mobile communications (5G FR2 @28 GHz) and wireless 802.11ay (@60 GHz) data access services on the mmWave frequency range. By means of an enhanced in-house deterministic 3D ray launching (3D-RL) simulation tool for RF-EMF exposure assessment, different complex heterogenous scenarios of high complexity are assessed in realistic operation conditions, considering different user distributions and densities. The use of directive antennas and MIMO beamforming techniques, as well as all the corresponding features in terms of radio wave propagation, such as the body shielding effect, dispersive material properties of obstacles, the impact of the distribution of scatterers and the associated electromagnetic propagation phenomena, are considered for simulation. Discussion regarding the contribution and impact of the coexistence of multiple heterogeneous networks and services is presented, verifying compliance with the current established international regulation limits with exposure levels far below the aforementioned limits. Finally, the proposed simulation technique is validated with a complete empirical campaign of measurements, showing good agreement. In consequence, the obtained datasets and simulation estimations, along with the proposed RF-EMF simulation tool, could be a reference approach for the design, deployment and exposure assessment of the current and future wireless communication technologies on the mmWave spectrum, where massive high-node density heterogeneous networks are expected.


Assuntos
Campos Eletromagnéticos , Exposição Ambiental , Comunicação , Ondas de Rádio , Tecnologia sem Fio
3.
Sensors (Basel) ; 21(21)2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34770558

RESUMO

For ultra-high field and frequency (UHF) magnetic resonance imaging (MRI), the associated short wavelengths in biological tissues leads to penetration and homogeneity issues at 10.5 tesla (T) and require antenna transmit arrays for efficiently generated 447 MHz B1+ fields (defined as the transmit radiofrequency (RF) magnetic field generated by RF coils). Previously, we evaluated a 16-channel combined loop + dipole antenna (LD) 10.5 T head array. While the LD array configuration did not achieve the desired B1+ efficiency, it showed an improvement of the specific absorption rate (SAR) efficiency compared to the separate 8-channel loop and separate 8-channel dipole antenna arrays at 10.5 T. Here we compare a 16-channel dipole antenna array with a 16-channel LD array of the same dimensions to evaluate B1+ efficiency, 10 g SAR, and SAR efficiency. The 16-channel dipole antenna array achieved a 24% increase in B1+ efficiency in the electromagnetic simulation and MR experiment compared to the LD array, as measured in the central region of a phantom. Based on the simulation results with a human model, we estimate that a 16-channel dipole antenna array for human brain imaging can increase B1+ efficiency by 15% with similar SAR efficiency compared to a 16-channel LD head array.


Assuntos
Imageamento por Ressonância Magnética , Ondas de Rádio , Encéfalo/diagnóstico por imagem , Desenho de Equipamento , Humanos , Imagens de Fantasmas
4.
Sensors (Basel) ; 21(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34770668

RESUMO

Ultraviolet and infrared sensors at high quantum efficiency on-board a small satellite (UVSQ-SAT) is a CubeSat dedicated to the observation of the Earth and the Sun. This satellite has been in orbit since January 2021. It measures the Earth's outgoing shortwave and longwave radiations. The satellite does not have an active pointing system. To improve the accuracy of the Earth's radiative measurements and to resolve spatio-temporal fluctuations as much as possible, it is necessary to have a good knowledge of the attitude of the UVSQ-SAT CubeSat. The attitude determination of small satellites remains a challenge, and UVSQ-SAT represents a real and unique example to date for testing and validating different methods to improve the in-orbit attitude determination of a CubeSat. This paper presents the flight results of the UVSQ-SAT's attitude determination. The Tri-Axial Attitude Determination (TRIAD) method was used, which represents one of the simplest solutions to the spacecraft attitude determination problem. Another method based on the Multiplicative Extended Kalman Filter (MEKF) was used to improve the results obtained with the TRIAD method. In sunlight, the CubeSat attitude is determined at an accuracy better than 3° (at one σ) for both methods. During eclipses, the accuracy of the TRIAD method is 14°, while it reaches 10° (at one σ) for the recursive MEKF method. Many future satellites could benefit from these studies in order to validate methods and configurations before launch.


Assuntos
Planeta Terra , Astronave , Ondas de Rádio , Luz Solar
5.
Int J Mol Sci ; 22(19)2021 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-34639063

RESUMO

Autophagy is involved in the degradation of melanosomes and the determination of skin color. TLR4 and tumor necrosis factor (TNF) signaling upregulates NF-kB expression, which is involved in the upregulation of mTOR. The activation of mTOR by UV-B exposure results in decreased autophagy, whereas radiofrequency (RF) irradiation decreases TLR4 and TNF receptor (TNFR) expression. We evaluated whether RF decreased skin pigmentation by restoring autophagy by decreasing the expression of TLR4 or TNFR/NF-κB/mTOR in the UV-B-irradiated animal model. UV-B radiation induced the expressions of TNFR, TLR, and NF-κB in the skin, which were all decreased by RF irradiation. RF irradiation also decreased phosphorylated mTOR expression and upregulated autophagy initiation factors such as FIP200, ULK1, ULK2, ATG13, and ATG101 in the UV-B-irradiated skin. Beclin 1 expression and the expression ratio of LC3-I to LC3-II were increased by UV-B/RF irradiation. Furthermore, melanin-containing autophagosomes increased with RF irradiation. Fontana-Masson staining showed that the amount of melanin deposition in the skin was decreased by RF irradiation. This study showed that RF irradiation decreased skin pigmentation by restoring melanosomal autophagy, and that the possible signal pathways which modulate autophagy could be TLR4, TNFR, NF-κB, and mTOR.


Assuntos
Autofagia/efeitos da radiação , Melaninas/biossíntese , Melanossomas/metabolismo , Ondas de Rádio , Pigmentação da Pele/efeitos da radiação , Raios Ultravioleta , Biomarcadores , Células Cultivadas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Imuno-Histoquímica , NF-kappa B/metabolismo , Receptores do Fator de Necrose Tumoral/genética , Receptores do Fator de Necrose Tumoral/metabolismo , Pigmentação da Pele/genética , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Receptor 4 Toll-Like/metabolismo
6.
Front Public Health ; 9: 721166, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660514

RESUMO

Normally, the impact of electromagnetic exposure on human health is evaluated by animal study. The biological effect caused by electromagnetic exposure on such experimental animals as rats has been proven to be dose-dependent. However, though the dose of radio frequency (RF) electromagnetic exposure described by the specific absorbing rate (SAR) on fixed rats has been relatively well-studied utilizing the numerical simulations, the dosimetry study of exposure on free rat is insufficient, especially in the cases of two or more free rats. Therefore, the present work focuses on the variation of SAR caused by the existence of neighboring free rat in the same cage. Here, infrared thermography was used to record the activity of the two free rats who lived in the same cage that mounted at the far-field region in the microwave darkroom for a duration of 48 h. Then, using image processing techniques, the relative positions and orientations of the two rats are identified, which are defined by three parameters, such as the relative distance (d), relative direction angle (α), and relative orientation angle (ß). Using the simulation software XFdtd 7.3, the influence of d, α, and ß on the whole-body average SAR (WB-avgSAR) of the rats exposed to 1.8 GHz electromagnetic wave was calculated and analyzed. Then, the average variation of WB-avgSAR of the two rats compared with that of a single rat within 48 h was calculated. The numerical simulation results showed that the relative posture position described by (d, α, and ß) of the two rats affects their WB-avgSAR and leads to fluctuations at different positions. However, the variation rate of the 48-h-average WB-avgSAR was only 10.3%, which implied that the over-time average SAR of two or more rats can be roughly described by the WB-avgSAR of a single free rat, except when a real-time precise control of exposure dose is necessary.


Assuntos
Ondas de Rádio , Radiometria , Animais , Simulação por Computador , Radiação Eletromagnética , Micro-Ondas , Ondas de Rádio/efeitos adversos , Ratos
7.
Bioelectromagnetics ; 42(8): 609-615, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34633685

RESUMO

Radiofrequency (RF) radiation from mobile phones has been classified as possibly carcinogenic to humans (2b) by IARC. However, to date, the discussion on whether mobile phone use is a cancer risk factor has not been solved. In this context of continuing uncertainty, it is important to continue to monitor cancer incidence trends. Annual incidence rates and directly age-standardized rates of selected cancers by sex and 5-year age groups for 1996 to 2017 for England were obtained from the UK Office for National Statistics. Interpretation in light of mobile phone use as a contributing risk factor was conducted for cancers of the brain, parotid gland, thyroid, and colorectal cancer, which have all been hypothesized to be associated with RF exposure. Brain and parotid gland cancers were updated by an additional 10 years following a previous publication, and continue to provide little evidence of an association with mobile phone use. Although mobile phone use as a potential risk factor contributing to increased incidence of colorectal or thyroid cancer could not be excluded based on these ecological data, it is implausible that it is an important risk factor for either. In the absence of clarity from epidemiological studies, it remains important to continue to monitor trends. However, for the time being, and in agreement with data from other countries, there is little evidence of an association between mobile phone use and brain or parotid gland cancer, while the hypotheses of associations with thyroid or colorectal cancer are similarly weak. © 2021 Bioelectromagnetics Society.


Assuntos
Neoplasias Encefálicas , Uso do Telefone Celular , Telefone Celular , Inglaterra/epidemiologia , Humanos , Incidência , Ondas de Rádio , Fatores de Risco
8.
Sensors (Basel) ; 21(19)2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34641002

RESUMO

In animal tracking applications, smaller transmitters can reduce the impact of the transmitter on the tagged animal and thus provide more accurate data about animal behavior. By combining a novel circuit design and a newly developed micro-battery, we developed frequency-programmable and more powerful radio frequency transmitters that are about 40% smaller and lighter in weight than the smallest commercial counterpart for animal monitoring at the time of development. The new radio frequency transmitter has a miniaturized form factor for studying small animals. Designs of two coding schemes were developed: one transmits unmodulated signals (weight: 152 mg; dimensions: Ø 2.95 mm × 11.22 mm), and the other transmits modulated signals (weight: 160 mg; dimensions: Ø 2.95 mm × 11.85 mm). To accommodate different transmitter life requirements, each design can be configured to transmit in high or low signal strength. Prototypes of these transmitters were evaluated in the laboratory and exhibited comparable or longer service life and higher signal strength compared to their smallest commercial counterparts.


Assuntos
Ondas de Rádio , Telemetria , Animais , Comportamento Animal
9.
Sensors (Basel) ; 21(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34696049

RESUMO

Indoor smart-farming based on artificial grow lights has gained attention in the past few years. In modern agricultural technology, the growth status is generally monitored and controlled by radio-frequency communication networks. However, it is reported that the radio frequency (RF) could negatively impact the growth rate and the health condition of the vegetables. This work proposes an energy-efficient solution replacing or augmenting the current RF system by utilizing light-emitting diodes (LEDs) as the grow lights and adopting visible light communications and optical camera communication for the smart-farming systems. In particular, in the proposed system, communication data is modulated via a 24% additional green grow LED light that is also known to be beneficial for the growth of the vegetables. Optical cameras capture the modulated green light reflected from the vegetables for the uplink connection. A combination of white ceiling LEDs and photodetectors provides the downlink, enabling an RF-free communication network as a whole. In the proposed architecture, the smart-farming units are modularized, leading to flexible mobility. Following theoretical analysis and simulations, a proof-of-concept demonstration presents the feasibility of the proposed architecture by successfully demonstrating the maximum data rates of 840 b/s (uplink) and 20 Mb/s (downlink).


Assuntos
Aplicações da Informática Médica , Dispositivos Ópticos , Fazendas , Monitorização Fisiológica , Ondas de Rádio
10.
Radiol Technol ; 93(1): 75-89, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34588280

RESUMO

Magnetic resonance (MR) imaging uses magnetic fields and radio waves to generate an image of the body. Though it is considered safe because it does not emit ionizing radiation, the strong magnetic fields produced by the MR scanner require unique safety considerations. The American College of Radiology (ACR) has provided guidance documents on MR safety since 2002 and recently updated and reorganized these documents into the ACR Manual on MR Safety. This article discusses the physics of MR imaging, the evolution of MR safety recommendations, and MR safety procedures.


Assuntos
Imageamento por Ressonância Magnética , Ondas de Rádio , Humanos , Campos Magnéticos , Física
11.
Front Public Health ; 9: 724239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513791

RESUMO

Objective: To examine whether exposure of mouse bone marrow stromal cells (BMSC) to 900 MHz radiofrequency fields used in mobile communication devices can induce mitochondrial unfolded protein response (UPRmt). Methods: BMSCs were exposed to continuous wave 900 MHz radiofrequency fields (RF) at 120 µW/cm2 power intensity for 4 h/d for 5 consecutive days. Cells in sham group (SH) were cultured in RF exposure system, but without RF radiation. The positive control cells were irradiated with 6 Gy X-ray at a dose rate of 1.103 Gy/min (XR). To inhibit the upstream molecular JNK2 of UPRmt, cells in siRNA + RF, and siRNA + XR group were also pretreated with 100 nM siRNA-JNK2 for 48 h before RF/XR exposure. Thirty minutes, 4 h, and 24 h post-RF/XR exposure, cells were collected, the level of ROS was measured with flow cytometry, the expression levels of UPRmt-related proteins were detected using western blot analysis. Results: Compared with Sham group, the level of ROS in RF and XR group was significantly increased 30 min and 4 h post-RF/XR exposure (P < 0.05), however, the RF/XR-induced increase of ROS level reversed 24 h post-RF/XR exposure. Compared with Sham group, the expression levels of HSP10/HSP60/ClpP proteins in cells of RF and XR group increased significantly 30 min and 4 h post-RF/XR exposure (P < 0.05), however, the RF/XR-induced increase of HSP10/HSP60/ClpP protein levels reversed 24 h post-RF exposure. After interfering with siRNA-JNK2, the RF/XR exposures could not induce the increase of HSP10/HSP60/ClpP protein levels any more. Conclusions: The exposure of 900 MHz RF at 120 µW/cm2 power flux density could increase ROS level and activate a transient UPRmt in BMSC cells. Mitochondrial homeostasis in term of protein folding ability is restored 24 h post-RF exposure. Exposure to RF in our experimental condition did not cause permanent and severe mitochondrial dysfunctions. However, the detailed underlying molecular mechanism of RF-induced UPRmt remains to be further studied.


Assuntos
Células-Tronco Mesenquimais , Ondas de Rádio , Animais , Células da Medula Óssea , Camundongos , Ondas de Rádio/efeitos adversos , Resposta a Proteínas não Dobradas
12.
Tomography ; 7(3): 466-476, 2021 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-34564302

RESUMO

Although hyperpolarization (HP) greatly increases the sensitivity of 13C MR, the usefulness of HP in vivo is limited by the short lifetime of HP agents. To address this limitation, we developed an echo-planar (EPI) sequence with spectral-spatial radiofrequency (SSRF) pulses for fast and efficient metabolite-specific imaging of HP [1-13C]pyruvate and [1-13C]lactate at 4.7 T. The spatial and spectral selectivity of each SSRF pulse was verified using simulations and phantom testing. EPI and CSI imaging of the rat abdomen were compared in the same rat after injecting HP [1-13C]pyruvate. A procedure was also developed to automatically set the SSRF excitation pulse frequencies based on real-time scanner feedback. The most significant results of this study are the demonstration that a greater spatial and temporal resolution is attainable by metabolite-specific EPI as compared with CSI, and the enhanced lifetime of the HP signal in EPI, which is attributable to the independent flip angle control between metabolites. Real-time center frequency adjustment was also highly effective for minimizing off-resonance effects. To the best of our knowledge, this is the first demonstration of metabolite-specific HP 13C EPI at 4.7 T. In conclusion, metabolite-specific EPI using SSRF pulses is an effective way to image HP [1-13C]pyruvate and [1-13C]lactate at 4.7 T.


Assuntos
Imagem Ecoplanar , Ácido Pirúvico , Animais , Ácido Láctico , Imagens de Fantasmas , Ondas de Rádio , Ratos
13.
Front Public Health ; 9: 691880, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34485223

RESUMO

With the rapid development of electronic information in the past 30 years, technical achievements based on electromagnetism have been widely used in various fields pertaining to human production and life. Consequently, electromagnetic radiation (EMR) has become a substantial new pollution source in modern civilization. The biological effects of EMR have attracted considerable attention worldwide. The possible interaction of EMR with human organs, especially the brain, is currently where the most attention is focused. Many studies have shown that the nervous system is an important target organ system sensitive to EMR. In recent years, an increasing number of studies have focused on the neurobiological effects of EMR, including the metabolism and transport of neurotransmitters. As messengers of synaptic transmission, neurotransmitters play critical roles in cognitive and emotional behavior. Here, the effects of EMR on the metabolism and receptors of neurotransmitters in the brain are summarized.


Assuntos
Telefone Celular , Encéfalo , Radiação Eletromagnética , Humanos , Neurotransmissores , Ondas de Rádio
14.
PLoS One ; 16(9): e0257077, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34492090

RESUMO

Ultra-high field MRI at 7 T can produce much better visualization of sub-cortical structures compared to lower field, which can greatly help target verification as well as overall treatment monitoring for patients with deep brain stimulation (DBS) implants. However, use of 7 T MRI for such patients is currently contra-indicated by guidelines from the device manufacturers due to the safety issues. The aim of this study was to provide an assessment of safety and image quality of ultra-high field magnetic resonance imaging at 7 T in patients with deep brain stimulation implants. We performed experiments with both lead-only and complete DBS systems implanted in anthropomorphic phantoms. RF heating was measured for 43 unique patient-derived device configurations. Magnetic force measurements were performed according to ASTM F2052 test method, and device integrity was assessed before and after experiments. Finally, we assessed electrode artifact in a cadaveric brain implanted with an isolated DBS lead. RF heating remained below 2°C, similar to a fever, with the 95% confidence interval between 0.38°C-0.52°C. Magnetic forces were well below forces imposed by gravity, and thus not a source of concern. No device malfunctioning was observed due to interference from MRI fields. Electrode artifact was most noticeable on MPRAGE and T2*GRE sequences, while it was minimized on T2-TSE images. Our work provides the safety assessment of ultra-high field MRI at 7 T in patients with DBS implants. Our results suggest that 7 T MRI may be performed safely in patients with DBS implants for specific implant models and MRI hardware.


Assuntos
Estimulação Encefálica Profunda , Aumento da Imagem , Imageamento por Ressonância Magnética , Artefatos , Humanos , Imagens de Fantasmas , Ondas de Rádio , Temperatura
15.
Neurourol Urodyn ; 40(8): 1862-1868, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34487571

RESUMO

AIMS: Sacral neuromodulation (SNM) has successfully treated patients with functional urinary and/or bowel disorders for more than two decades. Historically, patients with the InterStim system (Medtronic) were contraindicated for Magnetic Resonance Imaging (MRI) scans. In 2012, Medtronic obtained Food and Drug Administration (FDA) approval for allowing 1.5 Tesla (T) MRI head scans. In September 2019, the Axonics System (Axonics) received FDA approval for 1.5 T full-body MR Conditional labeling and then 3 T full-body MR Conditional labeling in July 2020. In August 2020, Medtronic received 1.5 and 3 T full-body MR Conditional labeling from the FDA for their new SNM systems (InterStim II and Micro devices with SureScanTM  leads). With the advancements in MRI technology and availability of full-body MRI eligible SNM systems, it is important for physicians to better understand MRI safety for these systems. METHODS: This paper explains the fundamentals of MRI physics, its interactions with active implantable medical devices (AIMDs), the subsequent potential safety hazards with emphasis on radio frequency (RF)-related safety, and the risks associated with "Off-label" scans, including abandoned and broken leads. RESULTS: MRI guidelines provided by the AIMD device manufacturer should be followed to ensure MRI scan safety and avoid any unnecessary risk to patients. CONCLUSIONS: MRI guidelines provided by the device manufacturer are the best resource for guidance for performing safe MRI scanning. Specific conditions should be fully understood and generalizations on MRI safety claims based on partial analysis or case studies should be avoided.


Assuntos
Terapia por Estimulação Elétrica , Imageamento por Ressonância Magnética , Terapia por Estimulação Elétrica/efeitos adversos , Humanos , Ondas de Rádio , Região Sacrococcígea , Sacro/diagnóstico por imagem
16.
Ann Agric Environ Med ; 28(3): 419-425, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34558264

RESUMO

INTRODUCTION AND OBJECTIVE: Electromagnetic radiation interactions with living systems have been one of determining factors in biological evolution. This study investigates the effect of 900 MHz radiofrequency (RF) electromagnetics field (EMF) exposure of eggs on the development of Dermacentor reticulatus larvae. The basic objective was to determine whether the 900 MHz RF-EMF has the potential to influence the size of the body of the hatched larvae of D. reticulatus ticks. MATERIAL AND METHODS: To this aim, eggs from 3 fully engorged females of D. reticulatus were included in the test procedure. Altogether four groups of eggs were designated which included eggs from each female. We used RF-EMF frequency of 900 MHz. Eggs were exposed to EMF for different time periods (30, 60 and 90 minutes) in dark, electromagnetically shielded anechoic chamber. After the irradiation eggs were allowed to hatch in climatic chamber. Randomly selected 200 larval individuals were measured to get basic morphological records. Four body traits including the total body length (TBL), length of gnathosoma with scutum (GSL), the total body width (TBW), and the width of basis capituli (BCW) were measured. RESULTS: The D. reticulatus larvae hatched from eggs exposed for 60 minutes, had demonstrably larger dimensions of all measured body traits not only as a control unexposed group but also as other experimental groups. CONCLUSIONS: The study shows, particularly, that artificial EMF that is used in smartphone technology impacts seriously D. reticulatus larvae development.


Assuntos
Dermacentor/crescimento & desenvolvimento , Larva/efeitos da radiação , Animais , Dermacentor/efeitos da radiação , Campos Eletromagnéticos , Feminino , Larva/crescimento & desenvolvimento , Masculino , Óvulo/crescimento & desenvolvimento , Óvulo/efeitos da radiação , Ondas de Rádio
17.
Sensors (Basel) ; 21(18)2021 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-34577356

RESUMO

Hyperspectral reflectance imaging in the short-wave infrared range (SWIR, "extended NIR", ca. 1000 to 2500 nm) has proven to provide enhanced characterization of paint materials. However, the interpretation of the results remains challenging due to the intrinsic complexity of the SWIR spectra, presenting both broad and narrow absorption features with possible overlaps. To cope with the high dimensionality and spectral complexity of such datasets acquired in the SWIR domain, one data treatment approach is tested, inspired by innovative development in the cultural heritage field: the use of a pigment spectral database (extracted from model and historical samples) combined with a deep neural network (DNN). This approach allows for multi-label pigment classification within each pixel of the data cube. Conventional Spectral Angle Mapping and DNN results obtained on both pigment reference samples and a Buddhist painting (thangka) are discussed.


Assuntos
Inteligência Artificial , Redes Neurais de Computação , Diagnóstico por Imagem , Pigmentação , Ondas de Rádio
18.
Environ Int ; 157: 106828, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34433115

RESUMO

BACKGROUND: The World Health Organization (WHO) has an ongoing project to assess potential health effects of exposure to radiofrequency electromagnetic fields (RF-EMF) in the general and working population. Here we present the protocol for a systematic review of the scientific literature on cancer hazards from exposure to RF-EMF in humans, commissioned by the WHO as part of that project. OBJECTIVE: To assess the quality and strength of the evidence provided by human observational studies for a causal association between exposure to RF-EMF and risk of neoplastic diseases. ELIGIBILITY CRITERIA: We will include cohort and case-control studies investigating neoplasia risks in relation to three types of exposure to RF-EMF: near-field, head-localized, exposure from wireless phone use (SR-A); far-field, whole body, environmental exposure from fixed-site transmitters (SR-B); near/far-field occupational exposures from use of handheld transceivers or RF-emitting equipment in the workplace (SR-C). While no restriction on tumour type will be applied, we will focus on selected neoplasms of the central nervous system (brain, meninges, pituitary gland, acoustic nerve) and salivary gland tumours (SR-A); brain tumours and leukaemias (SR-B, SR-C). INFORMATION SOURCES: Eligible studies will be identified through Medline, Embase, and EMF-Portal. RISK-OF-BIAS ASSESSMENT: We will use a tailored version of the OHAT's tool to evaluate the study's internal validity. DATA SYNTHESIS: We will consider separately studies on different tumours, neoplasm-specific risks from different exposure sources, and a given exposure-outcome pair in adults and children. When a quantitative synthesis of findings can be envisaged, the main aims of the meta-analysis will be to assess the strength of association and the shape of the exposure-response relationship; to quantify the degree of heterogeneity across studies; and explore the sources of inconsistency (if any). When a meta-analysis is judged inappropriate, we will perform a narrative synthesis, complemented by a structured tabulation of results and appropriate visual displays. EVIDENCE ASSESSMENT: Confidence in evidence will be assessed in line with the GRADE approach. FUNDING: This project is supported by the World Health Organization. Co-financing was provided by the New Zealand Ministry of Health; the Istituto Superiore di Sanità in its capacity as a WHO Collaborating Centre for Radiation and Health; ARPANSA as a WHO Collaborating Centre for Radiation Protection. REGISTRATION: PROSPERO CRD42021236798.


Assuntos
Neoplasias Encefálicas , Telefone Celular , Adulto , Criança , Campos Eletromagnéticos/efeitos adversos , Exposição Ambiental , Humanos , Metanálise como Assunto , Ondas de Rádio/efeitos adversos
19.
J Cosmet Dermatol ; 20(9): 2691-2702, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34333828

RESUMO

BACKGROUND: Radiofrequency (RF) is a non-invasive or minimally invasive procedure with a low risk of complications. It has been employed for several aesthetic purposes. AIM: This study aimed to conduct a systematic literature review on the use of RF for aesthetic applications and assess the level of accumulated evidence for each condition. METHODS: Using the MEDLINE/PubMed and EMBASE databases, we searched for articles published from 2009 to 2019 describing the use of RF treatment for aesthetic purposes. RESULTS: Our search approach identified 25 randomized clinical trials investigating the efficacy of RF in the following clinical situations: body contour improvement, facial rejuvenation, acne scar treatment, alopecia, and rosacea. There were problems with the quality of the studies, especially regarding selection, performance, and detection bias. CONCLUSION: Our study revealed that RF treatment is potentially promising in all of the evaluated clinical situations; however, we were not able to identify a level of evidence that justifies its use over other therapeutic options currently available on the market.


Assuntos
Alopecia , Rejuvenescimento , Estética , Humanos , Ondas de Rádio/efeitos adversos
20.
Bioelectromagnetics ; 42(7): 575-582, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34337771

RESUMO

The hazardous consequences of electromagnetic field (EMF) exposure represent a public health concern. Common sources of EMF include smartphones and wireless fidelity (Wi-Fi). The aim of our study is to assess whether exposure to Wi-Fi radiofrequency radiation influences the pathogenic traits of carbapenem-resistant Klebsiella pneumoniae. The susceptibility to antibiotics was evaluated by the determination of minimum inhibitory concentrations (MIC). In this study, K. pneumoniae showed a non-linear response to treatments with Colistin and Gentamycin following different Wi-Fi exposure periods. Transmission electron microscopy revealed morphological changes in the bacterial cell membrane within 24 h of Wi-Fi exposure. Crystal violet quantification and quantitative real-time polymerase chain reaction showed that the ability to form biofilms was greater in Wi-Fi exposed K. pnemoniae when compared to control. Moreover, higher levels of bcsA, mrkA, and luxS messenger RNAs were observed. Our data suggest that Wi-Fi exposure can influence bacteria in a stressful way, leading to an alteration in their antibiotic susceptibility, morphological changes, and cumulative biofilm formation. © 2021 Bioelectromagnetics Society.


Assuntos
Klebsiella pneumoniae , Ondas de Rádio , Carbapenêmicos/farmacologia , Campos Eletromagnéticos , Ondas de Rádio/efeitos adversos
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