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[ELF-MF occupational exposure: repeated measures on workers].

Research RF Safe Research Library Jan 1, 2007

This occupational exposure assessment used personal dosimeters to estimate ELF magnetic field exposure in 543 workers across 9 occupational settings in Emilia-Romagna. Median time-weighted average exposure was 0.14 microT, with tile production showing the highest setting-level TWA. Repeat measurements after 6–9…

[Evaluation of the genotoxicity of the extremely low frequency-magnetic fields (ELF-MF) in workers exposed for professional reasons].

Research RF Safe Research Library Jan 1, 2007

This occupational study assessed whether extremely low frequency magnetic fields (ELF-MF) are associated with genotoxicity using cytogenetic assays in 109 workers. Comparisons across exposure strata, including a highest-exposed subgroup (TWA > 1 microT), found no significant differences in CA, SCE, or MN outcomes.…

Biophoton emission of MDCK cell with hydrogen peroxide and 60 Hz AC magnetic field.

Research RF Safe Research Library Jan 1, 2007

This in vitro study measured biophoton/chemiluminescence emission from MDCK cells after inducing reactive oxygen species with hydrogen peroxide. The authors report that photon emission increased with hydrogen peroxide dose and that photomultiplier tube measurements agreed with fluorescence microscopy observations.…

[Effect of Earth magnetic field on circadian rhythm of total antioxidant capacity of human saliva in the North].

Research RF Safe Research Library Jan 1, 2007

This paper reports observations in northern inhabitants relating geomagnetic conditions to circadian rhythm patterns in saliva total antioxidant capacity. It states that the amplitude of the circadian rhythm decreases during both increased geomagnetic activity and magnetic calm, with the most favorable rhythm display…

The influence of combined magnetic field on the fusion of plant protoplasts.

Research RF Safe Research Library Jan 1, 2007

This laboratory study examined whether a weak alternating magnetic field tuned to the cyclotron frequency of Ca2+ and K+ ions influences fusion of tobacco and soya protoplasts. The abstract reports a 2–3× increase in protoplast fusion frequency under exposure. It also reports involvement of calcium ions in induction…

Current trends in Internet- and cell phone-based HIV prevention and intervention programs.

Research RF Safe Research Library Jan 1, 2007

This narrative review summarizes recent advances (as of Spring 2007) in Internet- and cell phone-based HIV prevention and intervention research. The authors report that few evaluation studies had been published in the prior year, though many programs were funded and under development. Available results are described…

Evaluation of mulitprobe radiofrequency technology in a porcine model.

Research RF Safe Research Library Jan 1, 2007

This animal study evaluated two multiprobe radiofrequency ablation device approaches in pigs, including an impedance-based algorithm and clustered/combination probes with and without a switcher controller. The Pringle maneuver was associated with larger ablation volumes and shorter ablation times in one experiment,…

Use of radiofrequency hepatic parenchymal transection device in hepatic hemangioma resection: early experience and lessons learned.

Research RF Safe Research Library Jan 1, 2007

This retrospective case series reviewed four resections of symptomatic giant cavernous hepatic hemangiomas using an RF-powered multiarray (Habib sealer) for hepatic parenchymal transection. No blood transfusions were required and no major biliary or vascular injuries were observed at 1-year follow-up; one…

[Fluorescence spectra analysis of papain treated by pulsed electric field].

Research RF Safe Research Library Jan 1, 2007

This in vitro study used fluorescence excitation, emission, and polarization spectra to assess structural changes in papain after pulsed electric field (PEF) treatment. Under the reported PEF conditions (50 kV/cm, 1500 Hz, 40 µs pulses, 19,800 pulses), papain activity decreased by 56.5%. Spectral changes (increased…

[A measurement of spontaneous magnetic field by satellites structures of harmonic spectrum].

Research RF Safe Research Library Jan 1, 2007

This study measured satellite structures of second- and third-harmonic spectra reflected from solid targets during femtosecond laser–plasma interactions using an optical multi-channel spectrometer. Red-shifted satellite structures of 2ω0 and 3ω0 were observed, and at ~10^18 W/cm^2 the inferred spontaneous magnetic…

AC electric field-induced alignment and long-range assembly of multi-wall carbon nanotubes inside aqueous media.

Research RF Safe Research Library Jan 1, 2007

This engineering study examines multi-wall carbon nanotubes suspended in water exposed to AC electric fields generated by 3D electrodes. It reports field-induced polarization leading to nanotube alignment and long-range, electrically conducting assemblies spanning the electrode gap, with assembly length controlled by…

[Reports on electromagnetic field strength measurements issued for occupational health and safety needs in the opinion of radio communication station users].

Research RF Safe Research Library Jan 1, 2007

This paper describes a modified approach for assessing occupational EMF exposure during work on radio and television towers and masts, where exposure can be high and tasks/routes are not fixed. The method calculates maximum admissible dwell time at different mast levels while incorporating the EMF dose accumulated…

Comparison of the effects of continuous and pulsed mobile phone like RF exposure on the human EEG.

Research RF Safe Research Library Jan 1, 2007

This study tested whether GSM-like RF exposure affects resting human EEG, focusing on alpha band power and non-linear EEG features. Using a fully counterbalanced cross-over design with 12 participants and a dipole antenna intended to better resemble handset exposure, the authors found no changes after 15 minutes of…

Magnetic field distribution and signal decay in functional mri in very high fields (up to 9.4 T) using monte carlo diffusion modeling.

Research RF Safe Research Library Jan 1, 2007

This paper models extravascular MRI signal decay (R2/R2*) as a function of blood oxygenation, vessel geometry, and magnetic field strength up to 9.4 T using Monte Carlo diffusion simulations. It reports different vessel-size dependencies for Hahn-spin-echo versus gradient-recalled-echo relaxation across field…

Effects of pulsed electromagnetic field vibration on tooth movement induced by magnetic and mechanical forces: a preliminary study.

Research RF Safe Research Library Jan 1, 2007

This randomized animal study tested whether pulsed electromagnetic field (PEMF)-induced vibration affects orthodontic tooth movement produced by magnetic and/or mechanical forces. Forty-four Wistar rats were exposed to PEMF-induced vibration or normal atmosphere while tooth movement was induced using magnets and/or…

[Acute ear trauma caused by failure of mobile phone/cellular phone].

Research RF Safe Research Library Jan 1, 2007

This case report describes acute acoustic and burn ear trauma associated with an apparent mobile phone failure during use. The patient had an external auditory canal burn and transient hearing loss, with tinnitus that persisted for weeks but resolved by one month. The authors state that the case suggests mobile phone…

Viability of fungal and actinomycetal spores after microwave radiation of building materials.

Research RF Safe Research Library Jan 1, 2007

This laboratory study tested microwave radiation (10 and 60 mW/cm2 for 5, 30, or 60 minutes) on fungal and actinomycetal spores grown on agar and on common building materials under wet and dry humidity conditions. Reported effects on spore viability depended on strain, growth conditions, humidity, power density, and…

Development of a patch antenna array RF coil for ultra-high field MRI.

Research RF Safe Research Library Jan 1, 2007

This engineering study describes development of a patch antenna array coil (PAAC) intended to address short RF wavelength challenges in ultra-high-field (≥7T) MRI. A prototype PAAC for 7T proton imaging was used to image a monkey brain. The authors report that the imaging demonstrated the coil's utility for…

Dependence of RF heating on SAR and implant position in a 1.5T MR system.

Research RF Safe Research Library Jan 1, 2007

This phantom study measured RF-induced heating of a stainless steel humerus implant during 1.5T MR imaging while varying SAR, implant angle to B0, and implant position in the RF coil. Temperature rise at implant tips increased linearly with SAR, with larger rises when the implant was parallel to B0. Heating decreased…

Chaotic mixing induced by a magnetic chain in a rotating magnetic field.

Research RF Safe Research Library Jan 1, 2007

This paper studies chaotic mixing driven by breakup and reformation of a magnetic particle chain under a rotating magnetic field using direct numerical simulation. The authors report that chain motion and the degree of chaos depend strongly on the Mason number, and that a limited Mason number range produces repeated…

Charge and current neutralization of an ion-beam pulse propagating in a background plasma along a solenoidal magnetic field.

Research RF Safe Research Library Jan 1, 2007

This paper reports analytical theory on how a small solenoidal magnetic field affects an ion-beam pulse propagating through background plasma. The authors predict enhanced self-electric and self-magnetic fields under a resonance-like condition (omegace ≈ omegape beta_b) attributed to a dynamo effect. The combined…

Polarization reversal in multiferroic TbMnO3 with a rotating magnetic field direction.

Research RF Safe Research Library Jan 1, 2007

This Physical Review Letters paper reports a method to reverse electric polarization in multiferroic TbMnO3 using a rotating magnetic-field direction, without applying an electric field or heat. The authors state that the direction of magnetic-field-induced polarization along the a axis is retained as a memory even…

Ultranarrow optical absorption and two-phonon excitation spectroscopy of Cu2O paraexcitons in a high magnetic field.

Research RF Safe Research Library Jan 1, 2007

This physics study reports ultranarrow optical absorption and two-phonon excitation spectroscopy of Cu2O paraexcitons in a high magnetic field at 1.2 K. A magnetic field enabled observation of an otherwise forbidden paraexciton absorption line and allowed measurement of field-dependent oscillator strength and energy…

Magnetic field switching between the two orbital-ordered states in DyVO3.

Research RF Safe Research Library Jan 1, 2007

This Physical Review Letters study investigates phase competition between spin- and orbital-ordered states in a DyVO3 single crystal. The abstract reports reentrant temperature-driven transitions in spin ordering and orbital ordering. It also reports that an applied magnetic field can switch between orbital-ordered…

Sine-Gordon description of Beresinskii-Kosterlitz-Thouless vortices in superconductors immersed in an external magnetic field.

Research RF Safe Research Library Jan 1, 2007

This theoretical paper investigates Beresinskii-Kosterlitz-Thouless vortex physics in two-dimensional superconductors under an external magnetic field using a sine-Gordon field-theory approach. The authors state that the model yields a straightforward definition of field-induced magnetization. They also report that…

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