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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…

Effect of two length scales on the properties of MgB(2) for arbitrary applied magnetic field.

Research RF Safe Research Library Jan 1, 2010

This paper analyzes anomalous magnetic-field and temperature dependences observed in MgB(2) superconductivity experiments using a two-order-parameter Ginzburg-Landau theory with two length scales. The authors numerically solve the nonlinear Ginzburg-Landau equations for arbitrary applied fields between Hc1 and Hc2 to…

Two-dimensional electron states bound to an off-plane donor in a magnetic field.

Research RF Safe Research Library Jan 1, 2010

A theoretical analysis is presented of electron states in a two-dimensional plane bound to an off-plane donor impurity under a magnetic field. The authors calculate energy levels (ground and first three excited states) variationally and report binding energies and mean orbital radii as functions of donor position and…

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…

Spin polarization induced by in-plane electric and magnetic fields in two-dimensional heavy-hole systems.

Research RF Safe Research Library Jan 1, 2010

This theoretical study uses a nonequilibrium Green function approach to analyze current-induced spin polarization in a two-dimensional heavy-hole system with cubic Rashba spin-orbit coupling under in-plane electric and magnetic fields. The authors report monotonic decreases in longitudinal conductivity with…

An extension of the Czjzek model for the distributions of electric field gradients in disordered solids and an application to NMR spectra of 71Ga in chalcogenide glasses.

Research RF Safe Research Library Jan 1, 2010

This paper discusses the Czjzek model for distributions of electric field gradient (EFG) tensors in disordered solids and highlights its underlying assumptions and characteristics. It then introduces an extended model that combines a defined local EFG environment with an adjustable Gaussian (Czjzek) noise term to…

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…

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…

[Treatment of benign prostatic hyperplasia by radiofrequency (TUNA): a monocentric study of 28 cases treated in ambulatory surgery].

Research RF Safe Research Library Jan 1, 2009

This monocentric study evaluated outpatient feasibility and outcomes of radiofrequency transurethral needle ablation (TUNA) for benign prostatic hyperplasia in patients who did not respond to medical therapy. In the outpatient subgroup, urinary symptom scores, quality of life, flow measures, and residual urine…

Cyanide orientational ordering and copper electric field gradients in CuCN.N2H4.

Research RF Safe Research Library Jan 1, 2009

This study reports solid-state NMR (13C and 15N MAS) measurements on CuCN·N2H4 to extract copper quadrupole coupling constants and characterize cyanide ordering. Ab initio calculations were used to determine electric field gradient and chemical shielding tensor orientations needed for spectral analysis. The authors…

Nonuniqueness of magnetic fields and energy derivatives in spin-polarized density functional theory.

Research RF Safe Research Library Jan 1, 2009

This theoretical paper analyzes consequences of nonuniqueness of the external magnetic field B(r) in spin-polarized density functional theory. It reports that for ground states the energy functional is not differentiable with respect to spin density, but one-sided derivatives can exist. The work links these one-sided…

Are people living next to mobile phone base stations more strained? Relationship of health concerns, self-estimated distance to base station, and psychological parameters.

Research RF Safe Research Library Jan 1, 2009

This cross-sectional study surveyed 57 participants about perceived proximity to mobile phone base stations, EMF-related concerns, and psychological strain, and also collected saliva biomarkers. Self-declared base station neighbors (≤100 m) showed higher salivary alpha-amylase and higher symptom checklist scores on…

Spatial and Temporal Variations of a Screening Current Induced Magnetic Field in a Double-Pancake HTS Insert of an LTS/HTS NMR Magnet.

Research RF Safe Research Library Jan 1, 2009

This engineering study measures and simulates screening current induced magnetic fields (SCF) in a Bi2223-tape HTS insert used in an LTS/HTS NMR magnet at 77 K. SCF was induced by the insert self-field, an external 5-T background magnet, and their combination, and axial field distributions and temporal variations…

Plasmonic array nanoantennas on layered substrates: modeling and radiation characteristics.

Research RF Safe Research Library Jan 1, 2009

This theoretical/engineering study models arrays of plasmonic core-shell nano-radiators positioned over layered substrates using a Green's function dipole approach. The model is validated with full-wave FDTD simulations. The authors report that nanoparticle arraying and multilayer substrate design can be used to…

Focused-ion-beam-assisted magnet fabrication and manipulation for magnetic field detection applications.

Research RF Safe Research Library Jan 1, 2009

This engineering study describes a focused-ion-beam-assisted technique for fabricating reduced-size NdFeB nanomagnets and integrating them onto a thin-film bulk acoustic resonator (FBAR). After bonding the magnet, the FBAR showed a downshift in resonance frequency and a reduced quality factor. The magnetic behavior…

Mobile phone technology for children with type 1 and type 2 diabetes: a parent survey.

Research RF Safe Research Library Jan 1, 2009

This cross-sectional web-based survey assessed parents' concerns about managing their children's diabetes and their attitudes toward a mobile-phone-integrated glucometer service that could transmit real-time glucose readings. Parents most commonly reported concerns about access to their child's health care provider,…

Evaluation of the efficacy of pulsed electromagnetic field in the management of patients with diabetic polyneuropathy.

Research RF Safe Research Library Jan 1, 2009

This randomized controlled trial evaluated low-power, low-frequency pulsed electromagnetic field (PEMF) therapy at 600 Hz and 800 Hz as an adjunct treatment for diabetic polyneuropathy. Thirty participants were randomized to 600 Hz PEMF, 800 Hz PEMF, or usual medical treatment for 12 days. The abstract reports…

[Effect of microwave radiation on primary cultured Sertoli cells].

Research RF Safe Research Library Jan 1, 2009

This in vitro study exposed primary cultured Sertoli cells to microwave radiation at 0, 30, or 100 mW/cm^2 for 5 minutes and assessed outcomes 6 hours later. The authors report no differences in apoptosis/death or intracellular Ca2+ at 30 mW/cm^2, though cell-cycle distribution shifted. At 100 mW/cm^2, intracellular…

[A preliminary study on role of acid sphingomyelinase in receptor clustering induced by 50-Hz magnetic fields].

Research RF Safe Research Library Jan 1, 2009

This in vitro study exposed human amnion (FL) cells to a 50-Hz sinusoidal magnetic field (0.4 mT) for 15 minutes and assessed epidermal growth factor receptor (EGFR) clustering. The authors report that magnetic field exposure induced EGFR clustering, and that this effect was blocked by imipramine, an acid…

Head-to-head comparison of coronary plaque evaluation between multislice computed tomography and intravascular ultrasound radiofrequency data analysis.

Research RF Safe Research Library Jan 1, 2008

This study compared coronary plaque assessment by 64-slice multislice computed tomography (MSCT) with virtual histology intravascular ultrasound (VH IVUS) in 50 patients. The Agatston score on MSCT correlated moderately with calcium volume measured by VH IVUS, and MSCT plaque categories broadly reflected differences…

Apparent violation of the Wiedemann-Franz law near a magnetic field tuned metal-antiferromagnetic quantum critical point.

Research RF Safe Research Library Jan 1, 2008

This paper reports calculations of interlayer electrical and thermal resistivity in a layered metal assuming Fermi-liquid quasiparticles inelastically scattered by two-dimensional antiferromagnetic spin fluctuations. The model yields linear-in-temperature behavior over a broad range and suggests that extrapolations…

Velocity modulation of microtubules in electric fields.

Research RF Safe Research Library Jan 1, 2008

This in vitro study reports that electric fields can control the velocity of microtubules gliding over a kinesin-coated surface. Assisting fields increased speed up to fivefold, while opposing fields slowed motion to zero, and sideways fields induced significant motion. The authors present a grab-and-release model to…

[Effect of 1.8 GHz radiofrequency electromagnetic fields on gene expression of rat neurons].

Research RF Safe Research Library Jan 1, 2008

This in vitro study exposed primary cultured rat neurons to 1.8 GHz RF-EMF at an average SAR of 2 W/kg and assessed gene expression changes. The authors report multiple differentially expressed genes after 24 h intermittent exposure and confirm exposure-dependent changes in Egr-1, Mbp, and Plp by semi-quantitative…

[Influence of electromagnetic radiation on raf kinase inhibitor protein and its related proteins of hippocampus].

Research RF Safe Research Library Jan 1, 2008

This rat study examined hippocampal RKIP and related markers after exposure to high power microwaves (X-band and S-band) or an electromagnetic pulse. RKIP protein decreased at 6 hours post-exposure, with recovery by 1 day in the EMP group but more prolonged decreases (up to ~7 days) in the microwave groups.…

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