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Showing results for: SAR

Exposure to RF-EMF Alters Postsynaptic Structure and Hinders Neurite Outgrowth in Developing Hippocampal Neurons of Early Postnatal Mice.

Research RF Safe Research Library Jan 1, 2021

This animal and primary neuron culture study exposed early postnatal mice to whole-body RF-EMF (SAR 4.0 W/kg) for 5 hours/day from P1 to P28. The authors report reductions in dendritic spine measures (notably mushroom-type spines), decreased glutamate receptor expression in mushroom-type spines, and lower BDNF…

Activation of matrix metalloproteinases and FoxO3a in HaCaT keratinocytes by radiofrequency electromagnetic field exposure.

Research RF Safe Research Library Jan 1, 2021

This in vitro study exposed HaCaT human keratinocytes to 1760 MHz RF-EMF (SAR 4.0 W/kg; 2 h/day for 4 days). The authors report increased intracellular ROS and increased expression/activity of several matrix metalloproteinases, along with increased phosphorylation of FoxO3a and ERK1/2. Cell growth/viability and…

Effect of Exposure to a Radiofrequency Electromagnetic Field on Body Temperature in Anesthetized and Non-Anesthetized Rats.

Research RF Safe Research Library Jan 1, 2020

This animal study examined whether anesthesia and body mass modify body temperature responses to 915 MHz RF exposure at 4 W/kg whole-body SAR for 8 hours. Non-anesthetized, free-moving rats showed no significant temperature change during exposure. In contrast, anesthetized rats showed marked temperature increases,…

Modelling the Influence of Electromagnetic Field on the User of a Wearable IoT Device Used in a WSN for Monitoring and Reducing Hazards in the Work Environment.

Research RF Safe Research Library Jan 1, 2020

This modeling study estimated SAR in a multi-layer head model from a wearable IoT device’s Wi‑Fi/Bluetooth antenna. SAR was reported to be up to 10× higher when the antenna was placed in a headband versus on a helmet. The authors suggest that devices emitting below 3 mW EIRP may be considered environmentally…

Microtubular structure impairment after GSM-modulated RF radiation exposure.

Research RF Safe Research Library Jan 1, 2020

This in vitro study exposed V79 cells to 915 MHz GSM-modulated RF radiation for 1–3 hours at 10–30 V/m (average SARs reported as 0.23–1.6 W/kg). The authors report that 3-hour exposure altered microtubule structure across all tested field strengths and reduced cell growth on the third post-exposure day. They conclude…

Supervised Machine Learning Algorithms for Bioelectromagnetics: Prediction Models and Feature Selection Techniques Using Data from Weak Radiofrequency Radiation Effect on Human and Animals Cells.

Research RF Safe Research Library Jan 1, 2020

This paper develops supervised machine-learning prediction models to analyze potential impacts of weak RF-EMF on human and animal cells using extracted laboratory experimental data from prior publications. Data from 300 peer-reviewed papers (1127 experimental case studies) were used with feature selection and…

Radiofrequency applicator concepts for thermal magnetic resonance of brain tumors at 297 MHz (7.0 Tesla).

Research RF Safe Research Library Jan 1, 2020

This engineering/simulation study evaluates RF applicator concepts for ThermalMR brain tumor heating at 297 MHz (7.0 Tesla) using clinically realistic GBM-based models. EMF simulations compared 10 applicator designs and two SAR-based planning algorithms for small and large target volumes. Power-focused optimization…

Wideband Self-Grounded Bow-Tie Antenna for Thermal MR.

Research RF Safe Research Library Jan 1, 2020

This engineering study designed and tested a compact wideband self-grounded bow-tie RF antenna module for a whole-body 7.0 T MRI system, aiming to enable 1H/19F MRI, MR thermometry, and broadband RF thermal intervention. The authors report validated B1 efficiency measurements and phantom-based heating experiments…

An Evaluation of Electromagnetic Exposure While Using Ultra-High Frequency Radiofrequency Identification (UHF RFID) Guns.

Research RF Safe Research Library Jan 1, 2019

This study simulated SAR from handheld UHF RFID readers (“RFID guns”) in adult male and female models across seven close-proximity scenarios involving an operator, scanned person, or bystander. SAR was reported to comply with general public limits at emissions up to 1 W, but higher-power devices (>2 W, and especially…

The specific absorption rate in different brain regions of rats exposed to electromagnetic plane waves.

Research RF Safe Research Library Jan 1, 2019

This study develops a numerical voxel rat model with 10 segmented brain regions to evaluate region-specific dosimetry under plane-wave EMF exposure. It reports that brain-region averaged SAR varies with frequency, incidence direction, and E-polarization direction. The authors also report potentially large deviations…

Electromagnetic Energy Absorption in a Head Approaching a Radiofrequency Identification (RFID) Reader Operating at 13.56 MHz in Users of Hearing Implants Versus Non-Users.

Research RF Safe Research Library Jan 1, 2019

This modeling study estimated SAR in a head approaching a 13.56 MHz RFID HF reader, comparing hearing-implant users with non-users. The abstract reports that BAHA implants can increase localized SAR (10 g) versus non-users, up to 2.1× in a worst-case scenario, and that this increase is statistically higher than for…

Decreased dopamine in striatum and difficult locomotor recovery from MPTP insult after exposure to radiofrequency electromagnetic fields.

Research RF Safe Research Library Jan 1, 2019

This animal study reports that chronic RF-EMF exposure (835 MHz, SAR 4.0 W/kg, 5 h/day for 12 weeks) affected striatal neuronal markers in C57BL/6 mice. The authors observed reductions in synaptic vesicle-related measures and dopaminergic markers, including dopamine concentration and tyrosine hydroxylase expression.…

Hepatocellular carcinoma therapy finds a channel on the radio

Research RF Safe Research Library Jan 1, 2019

This EBioMedicine commentary discusses tumour-specific amplitude-modulated RF EMF as an anti-cancer therapy for hepatocellular carcinoma and highlights Cav3.2 (CACNA1H) T-type calcium channels as a proposed mediator of the effect. It notes that the reported whole-body averaged SAR in a treated HCC patient was below…

Impact of Long-Term RF-EMF on Oxidative Stress and Neuroinflammation in Aging Brains of C57BL/6 Mice.

Research RF Safe Research Library Jan 1, 2018

This animal study exposed 14-month-old C57BL/6 mice to 1950 MHz RF-EMF (SAR 5 W/kg) for 8 months. The authors report that aging was associated with increased oxidative damage, DNA damage, apoptosis, and glial activation markers in brain tissue. Long-term RF-EMF exposure did not change these markers in aged mice and…

A Single Exposure to GSM-1800 MHz Signals in the Course of an Acute Neuroinflammatory Reaction can Alter Neuronal Responses and Microglial Morphology in the Rat Primary Auditory Cortex.

Research RF Safe Research Library Jan 1, 2018

This animal study examined whether acute GSM-1800 MHz exposure affects the auditory cortex during experimentally induced neuroinflammation. In LPS-treated rats, a single 2-hour head-only exposure (average SAR 1.55 W/kg in auditory cortex) was associated with altered microglial morphology and reduced neuronal activity…

Evaluation of MRI RF electromagnetic field induced heating near leads of cochlear implants.

Research RF Safe Research Library Jan 1, 2018

This simulation study evaluated RF-induced heating near cochlear implant leads during 1.5 T MRI using a transfer function method. Across studied configurations, the average temperature rise was 0.79 °C and the maximum was 2.80 °C at a whole-body average SAR of 2 W/kg. The authors report that lead trajectory and MRI…

Gene Expression Analysis in Human Peripheral Blood Cells after 900 MHz RF-EMF Short-Term Exposure.

Research RF Safe Research Library Jan 1, 2018

This ex vivo/in vitro study exposed peripheral blood cells from five human donors to a 900 MHz continuous-wave RF-EMF for up to 90 minutes (average SAR 9.3 W/kg). After false discovery rate adjustment, the authors report no EMF-specific gene expression changes on microarray analysis. Although low-stringency analysis…

Effects of 1800 MHz RF-EMF exposure on DNA damage and cellular functions in primary cultured neurogenic cells.

Research RF Safe Research Library Jan 1, 2018

This in vitro study exposed primary cultured astrocytes, microglia, and cortical neurons to 1800 MHz RF-EMF at 4.0 W/kg SAR to assess DNA damage and cellular functions. The authors report no significant induction of γH2AX foci and no significant changes in cytokine secretion or dendrite/synapse morphological…

SAR thresholds for electromagnetic exposure using functional thermal dose limits.

Research RF Safe Research Library Jan 1, 2018

This paper analyzes how conservative current localized RF EMF SAR basic restrictions may be by estimating the implied safety factor. The authors derive thermal dose–functional SAR limits from literature-reported thresholds for acute local tissue damage and compare these to existing basic restrictions. They report…

Effects of 1950 MHz radiofrequency electromagnetic fields on Aβ processing in human neuroblastoma and mouse hippocampal neuronal cells.

Research RF Safe Research Library Jan 1, 2018

This in vitro study exposed HT22 mouse hippocampal neuronal cells and SH-SY5Y human neuroblastoma cells to 1950 MHz RF-EMF at SAR 6 W/kg for 2 hours per day over 3 days. RF-EMF exposure reduced mRNA levels of several Aβ-processing genes in HT22 cells, but did not change APP mRNA in SH-SY5Y cells. Protein levels of…

2.45 GHz microwave radiation induced oxidative and nitrosative stress mediated testicular apoptosis: Involvement of a p53 dependent bax-caspase-3 mediated pathway.

Research RF Safe Research Library Jan 1, 2018

This animal study exposed 12-week-old male mice to 2.45 GHz continuous-wave microwave radiation (average power density 0.0248 mW/cm; whole-body SAR 0.0146 W/kg) for 2 hours/day over 15, 30, or 60 days. The authors evaluated testicular histology, testosterone, oxidative/nitrosative stress markers, antioxidant enzymes,…

After-effect induced by microwave radiation in human electroencephalographic signal: a feasibility study.

Research RF Safe Research Library Jan 1, 2018

This feasibility study tested whether microwave radiation (450 MHz, 40 Hz modulation; 1 g peak spatial average SAR 0.3 W/kg) can induce detectable event-related potentials in EEG. In one subject across four sessions, EEG responses time-locked to exposure offset showed increased alpha-band signal and about a twofold…

NTP Technical Report on the Toxicology and Carcinogenesis Studies: GSM- and CDMA-modulated Cell Phone RFR, NTP TR 595

Research RF Safe Research Library Jan 1, 2018

This NTP technical report describes long-term rat studies exposing animals to 900 MHz GSM and CDMA-modulated radiofrequency radiation at whole-body SAR levels of 0, 1.5, 3, and 6 W/kg, including exposure beginning before birth. The abstract reports NTP concluded there was "clear evidence" for malignant schwannoma of…

RF-EMF exposure at 1800 MHz did not elicit DNA damage or abnormal cellular behaviors in different neurogenic cells.

Research RF Safe Research Library Jan 1, 2017

This in vitro study assessed whether intermittent 1800 MHz RF-EMF exposure induces DNA damage or alters cellular behavior in three neurogenic cell lines. Cells were exposed at an average SAR of 4.0 W/kg for 1, 6, or 24 hours and evaluated for γH2AX foci, cell cycle progression, proliferation, and viability. The…

Antenna Design and SAR Analysis on Human Head Phantom Simulation for Future Clinical Applications.

Research RF Safe Research Library Jan 1, 2017

This study developed a mathematical and computer simulation model to analyze RF-EMF exposure in a human head phantom, motivated by potential therapeutic applications. The modeled exposure used a Yagi-Uda antenna at 64 MHz with SAR 0.6 W/kg and compared field distribution using one versus four antennas. COMSOL Bioheat…

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