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Increased blood oxygen level-dependent (BOLD) sensitivity in the mouse somatosensory cortex during electrical forepaw stimulation using a cryogenic radiofrequency probe.

Research RF Safe Research Library Jan 1, 2011

This engineering-focused mouse fMRI study evaluated a 400-MHz cryogenic RF probe (CryoProbe) versus a conventional room-temperature surface coil during electrical forepaw stimulation. The CryoProbe increased image SNR and temporal SNR and reduced temporal noise compared with the room-temperature coil. The authors…

Reduction of implant RF heating through modification of transmit coil electric field.

Research RF Safe Research Library Jan 1, 2011

This engineering study describes modifying MRI RF transmit coil electric-field distributions to create electric field-free zones without substantially changing transmit sensitivity. Phantom experiments are reported to show reduced implant heating when a zero electric-field plane is aligned with the implant location.…

Correction of main and transmit magnetic field (B0 and B1) inhomogeneity effects in multicomponent-driven equilibrium single-pulse observation of T1 and T2.

Research RF Safe Research Library Jan 1, 2011

This methods paper addresses how B0 (main field) and B1 (transmit field) inhomogeneities can bias SPGR and bSSFP steady-state MRI signals used for multicomponent T1/T2 relaxometry and myelin water analysis. It describes using DESPOT1-HIFI to calibrate flip angles and adding a B0-related parameter with multiple…

Frequency-dependent electrodeformation of giant phospholipid vesicles in AC electric field.

Research RF Safe Research Library Jan 1, 2010

This paper presents a theoretical model of giant phospholipid vesicle deformation in an alternating-current electric field, based on minimizing membrane bending energy and electric-field energy. The model treats the membrane and surrounding aqueous media as leaky dielectrics and reports good quantitative agreement…

A rapid and facile synthesis of nanofibrillar polyaniline using microwave radiation.

Research RF Safe Research Library Jan 1, 2010

This engineering study describes a microwave-assisted method to synthesize polyaniline (PANI) nanofibers. Reported yields under microwave irradiation were similar to conventional synthesis but achieved in minutes rather than hours. Structural and morphological characterization (FTIR, Raman, SEM, TEM) reportedly…

Orientation and Dynamics of ZnO Nanorod Liquid Crystals in Electric Fields.

Research RF Safe Research Library Jan 1, 2010

This materials study reports that ZnO nanorod polymer hybrids can form liquid-crystalline phases and exhibit orientation switching under an applied AC electric field. The orientation reportedly changes from planar to homeotropic, analogous to switching in low-molecular liquid crystals. Dielectric measurements and…

High-intensity pulsed electric fields processing parameters affecting polyphenoloxidase activity of strawberry juice.

Research RF Safe Research Library Jan 1, 2010

This study evaluated high-intensity pulsed electric fields (HIPEF) as a processing method to inactivate polyphenoloxidase (PPO) in strawberry juice. Using response surface methodology at a constant electric field of 35 kV/cm, the authors report strong PPO reductions across tested parameter ranges. Bipolar mode,…

[Dependence of the non-thermal radiofrequency electromagnetic field bioeffects on the typological features of electroencephalogram in humans].

Research RF Safe Research Library Jan 1, 2010

This volunteer study examined short-term non-thermal RF EMF exposure and reported changes in EEG spectra. The main reported effect was amplification of alpha-range energy, with the magnitude depending on baseline EEG typological features. The abstract also reports that combining RF EMF exposure with monotonous…

Electrooptical effects in colloid systems subjected to short pulses of strong electric field.

Research RF Safe Research Library Jan 1, 2010

This study describes an electrooptical technique for polydisperse colloid solutions using short pulses of strong sine-shaped electric field, intended for systems that cannot withstand prolonged field exposure. The authors report that key particle parameters can still be extracted from the resulting experimental data.…

Spin current pumped by a rotating magnetic field in zigzag graphene nanoribbons.

Research RF Safe Research Library Jan 1, 2010

This theoretical study models electron spin resonance and spin/charge pumping in zigzag graphene nanoribbons driven by a transverse rotating magnetic field without applied bias. It reports that pumped spin current density increases with ribbon size and rotating-field intensity, and that even-chain ribbons can also…

High magnetic field induced charge density waves and sign reversal of the Hall coefficient in graphite.

Research RF Safe Research Library Jan 1, 2010

This condensed-matter study investigates highly oriented pyrolytic graphite under very strong magnetic fields at low temperature. It reports a magnetic-field-induced charge density wave transition and a subsequent sign reversal of the Hall coefficient from negative to positive. The reported angular dependence…

Effects of magnetic field and pressure on the intermediate valence state of YbPd.

Research RF Safe Research Library Jan 1, 2010

This condensed-matter physics study examined how high magnetic fields and pressure affect magnetization, transport, and thermodynamic properties of the intermediate-valence compound YbPd. The authors report that the Yb valence state and two first-order transitions are stable up to 55 T, while increasing pressure…

The effect of magnetic field and disorders on the electronic transport in graphene nanoribbons.

Research RF Safe Research Library Jan 1, 2010

This paper presents a mesoscopic transport modeling framework (NEGF plus a real-space π-orbital model) to study how a uniform perpendicular magnetic field affects electronic transport in armchair graphene nanoribbons. The authors report width-dependent equilibrium current profiles and edge-localized transport under…

Electronic properties of a graphene antidot in magnetic fields.

Research RF Safe Research Library Jan 1, 2010

This paper describes unusual electronic properties of a graphene antidot created by a piecewise constant potential in a magnetic field. It reports near-complete localization of electron probability within the barrier region under some conditions and a symmetry linking antidot and dot states with identical…

Electron dynamics in inhomogeneous magnetic fields.

Research RF Safe Research Library Jan 1, 2010

This paper is a review of two-dimensional electron dynamics in microscopically inhomogeneous magnetic fields, focusing on magnetic potentials varying on scales smaller than the mean free path. It covers early work on localization in random magnetic fields, methods to fabricate magnetic potentials, and drift-diffusion…

Quantitative determination of domain distribution in SrTiO3-competing effects of applied electric field and mechanical stress.

Research RF Safe Research Library Jan 1, 2010

This neutron diffraction study quantifies how tetragonal structural domains in SrTiO3 redistribute below 105 K under external electric fields and uniaxial mechanical stress. The authors report that electric field and stress act competitively, and that applying both produces complex domain redistribution. The results…

Pressure and magnetic field dependence of valence and magnetic transitions in EuPtP.

Research RF Safe Research Library Jan 1, 2010

This laboratory study investigates how magnetic field and pressure affect valence and magnetic transitions in the compound EuPtP. High-field analysis suggests a mixed valence state at low temperature and discontinuous changes in Eu2+ fraction at two transition temperatures. Pressure increases the transition…

Thermodynamic behavior of the XXZ Heisenberg s = 1/2 chain around the factorizing magnetic field.

Research RF Safe Research Library Jan 1, 2010

This paper theoretically investigates zero- and finite-temperature behavior of an anisotropic antiferromagnetic Heisenberg XXZ spin-1/2 chain under a transverse magnetic field, focusing between the factorizing and critical fields. It reports an entanglement phase transition at the factorizing field where entanglement…

Electric field gradients in (111)In-doped (Hf/Zr)3Al2 and (Hf/Zr)4Al3 mixed compounds: ab initio calculations, perturbed angular correlation measurements and site preference.

Research RF Safe Research Library Jan 1, 2010

This materials-physics study investigated quadrupolar hyperfine interactions of (111)In→(111)Cd probes in polycrystalline Zr4Al3 and Hf4Al3 containing minority (Zr/Hf)3Al2 phases. The authors observed a strong preference of (111)In solutes for the minority (Zr/Hf)3Al2 phases. Ab initio EFG calculations were used to…

The modulation of the de Haas-van Alphen effect in graphene by electric field.

Research RF Safe Research Library Jan 1, 2010

This theoretical/physics paper examines how an in-plane uniform electric field affects the de Haas-van Alphen (dHvA) effect in graphene. It reports that magnetization, magnetic susceptibility, and dHvA oscillation behavior depend on a dimensionless parameter β = E/(vF B), with divergences described at a critical…

Slow relaxation of magnetoresistance in AlGaAs-GaAs quantum well structures quenched in a magnetic field.

Research RF Safe Research Library Jan 1, 2010

This study reports slow relaxation of magnetoresistance in selectively doped p-GaAs-AlGaAs structures following application of a magnetic field. The authors emphasize efforts to rule out temperature fluctuation artifacts and state that the main relaxation features remain. They interpret the phenomenon using a…

Disordered electrical potential observed on the surface of SiO2 by electric field microscopy.

Research RF Safe Research Library Jan 1, 2010

This study characterizes the electrical potential on the surface of ~300 nm SiO2 grown on single-crystalline Si under ambient conditions using electric field microscopy. It reports an inhomogeneous surface potential with fluctuations up to ~0.4 V over ~1 µm regions. The authors propose these fluctuations could affect…

Pedestrians, vehicles, and cell phones.

Research RF Safe Research Library Jan 1, 2010

This study used an immersive virtual environment to examine how divided attention affects pedestrian street-crossing performance. Thirty-six participants crossed virtual streets while undistracted, conversing hands-free on a cell phone, or listening to music. Cell phone conversation was associated with a lower…

Nanocrystalline hydroxyapatite bioceramic using microwave radiation: Synthesis and characterization.

Research RF Safe Research Library Jan 1, 2010

This engineering/materials study synthesized nanocrystalline hydroxyapatite bioceramic powder using microwave radiation and then characterized the resulting material. The authors report highly crystalline HAp nanopowder with nanoscale size, mixed morphology, and elemental composition consistent with the HAp phase.…

The effects of microwave emitted by cellular phones on ovarian follicles in rats

Research RF Safe Research Library Jan 1, 2009

This animal study examined whether prenatal exposure to mobile phone microwaves affects ovarian development in rats. Pregnant rats were exposed to a phone placed under the cage throughout pregnancy, with mostly standby exposure and brief periodic speech-mode exposure. Female pups assessed at 21 days had fewer ovarian…

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