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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…

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…

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…

Electric field induced structuring in clay-oil suspensions: new insights from WAXS, SEM, leak current, dielectric permittivity, and rheometry.

Research RF Safe Research Library Jan 1, 2010

This laboratory/engineering study examined electric-field-induced structuring in clay-oil suspensions using WAXS, SEM, rheometry, and electrical measurements. Particle orientation was quantified via an orientational order parameter derived from diffraction peak azimuthal changes, and chain versus column formation was…

Ultrasonic propagation velocity in magnetic and magnetorheological fluids due to an external magnetic field.

Research RF Safe Research Library Jan 1, 2010

This engineering-focused study measured ultrasonic propagation velocity in hydrocarbon-based magnetic and magnetorheological fluids under an external magnetic field. The authors report that clustering structures formed in the fluids influence ultrasonic propagation velocity, with observed hysteresis and anisotropy.…

Localizing Broca's area for transcranial magnetic stimulation: Comparison of surface distance measurements and stereotaxic positioning.

Research RF Safe Research Library Jan 1, 2009

This methods study evaluated an MRI-based surface distance measurements (SDM) approach for localizing Broca's area for TMS coil placement without external tracking devices. Coil positioning using SDM was compared with an advanced frameless stereotaxic navigation system. The reported mean difference between methods…

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…

Dominant mobility modulation by the electric field effect at the LaAlO3/SrTiO3 interface.

Research RF Safe Research Library Jan 1, 2009

This Physical Review Letters paper reports magnetotransport measurements on a gated LaAlO3/SrTiO3 interface to assess the main effect of an applied gate electric field. The authors find that mobility changes dominate over sheet carrier density changes (mobility variation reported as nearly fivefold larger). They also…

Synthesis of polylactic acid-polyglycolic acid blends using microwave radiation.

Research RF Safe Research Library Jan 1, 2008

This engineering/materials study describes blending PLLA and PGA using microwave irradiation to produce PLGA-related blends with varying constituent concentrations. The authors report that FTIR, NMR, and DSC measurements indicate blending and cross-linking between the polymers. The abstract does not provide microwave…

The effect of MRET polymer compound on SAR values of RF phones.

Research RF Safe Research Library Jan 1, 2008

This article describes a hypothesis and experimental testing of an MRET polymer compound applied to RF phones. It reports increased dielectric permittivity in water-based solutions and reduced SAR values in a tissue-simulating phantom head. It also reports no significant change in air measurements of phone signals,…

In vivo quantification of contrast agent concentration using the induced magnetic field for time-resolved arterial input function measurement with MRI.

Research RF Safe Research Library Jan 1, 2008

This Medical Physics article presents a phase-based MRI method to quantify paramagnetic contrast agent concentration by inverting susceptibility-induced magnetic field shifts, aiming to improve arterial input function (AIF) measurement in DCE-MRI. After in vitro validation, the approach was applied in vivo in 14…

[Microstrip antenna design and system research of radio frequency identification temperature sensor].

Research RF Safe Research Library Jan 1, 2008

This engineering paper introduces an RFID sensor network concept integrating RFID with wireless sensor networks and emphasizes the role of antennas. It discusses coil, dipole, and microstrip antennas and reports designing a microstrip antenna for a wireless temperature monitoring and control system. Measurements are…

Single access point localisation for wearable wireless sensors.

Research RF Safe Research Library Jan 1, 2008

This engineering conference paper describes a single access point method for localizing a subject using RF signals from wearable wireless sensors. The approach combines RSSI and LQI measurements from one basestation and applies filtering. The abstract reports that accuracy can approach that of multi-basestation…

Position-independent chemical quantitation with passive 13.56-MHz radio frequency identification (RFID) sensors.

Research RF Safe Research Library Jan 1, 2008

This engineering study evaluates whether passive 13.56-MHz RFID-based chemical sensors can quantify analytes reliably despite repositioning errors between the sensor and pickup coil. Using simultaneous measurement of multiple complex-impedance parameters and multivariate statistical analysis, the authors report…

In-line application of electric field in capillary separation systems: Joule heating, pH and conductivity.

Research RF Safe Research Library Jan 1, 2008

This engineering study investigated factors affecting current when an electric field is applied in-line in a capillary separation system. Temperature measurements and a replicated cooling setup were used to estimate Joule heating effects, which were reported to be relatively small. In contrast, significant pH shifts…

Microscopic observation of living cells during their exposure to modulated electromagnetic fields.

Research RF Safe Research Library Jan 1, 2008

This paper describes an exposure and microscopy system designed to continuously observe living cells during exposure to modulated RF-EMF similar to mobile phone signals. Using protocols where the same cells serve as controls before and after exposure, the system was validated with endocytosis measurements. Under 900…

[The impact of treatment by extremely low frequency magnetic fields on the electropotentials in an oral cavity and some chemical elements content in saliva].

Research RF Safe Research Library Jan 1, 2007

This study reports measurements in 25 dental patients treated with the Viofor JPS system using extremely low frequency magnetic fields. Following a series of treatments, oral cavity electropotentials decreased and saliva pH increased. Copper levels in non-stimulated saliva decreased, while other measured elements…

Magnetic field exposure in a nondestructive testing operation.

Research RF Safe Research Library Jan 1, 2007

This exposure assessment measured peak magnetic fields during magnetic particle inspection, a nondestructive testing method that uses electromagnetism. Ninety-five peak measurements taken while inspecting 8 turbine engine shafts ranged from

[Measurements of professional exposure to ELF fields in some production areas within the territory of Regione Campania and comparison with the action values according to 2004/40/CE Directive].

Research RF Safe Research Library Jan 1, 2007

This occupational exposure assessment measured ELF magnetic fields in 400 workers across 80 work areas in several production sectors in Regione Campania. Measurements were taken continuously over two shifts and processed into RMS magnetic-field values. The authors report no exceedance of the EU 2004/40/CE action…

[Assessment of radiofrequency electromagnetic fields levels in the Taranto area].

Research RF Safe Research Library Jan 1, 2007

This study reports punctual monitoring of RF electromagnetic fields from radiobase stations in the Taranto area, with measurement campaigns conducted from November 2005 to March 2007. Measurements covered 108 transmitting stations across multiple communication technologies within 100 kHz to 3 GHz. Most monitored…

[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…

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.…

[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…

[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…

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…

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