Archive

1485 posts

Showing results for: CT

Electric field analysis of breast tumor cells.

Research RF Safe Research Library Jan 1, 2011

This paper reports a MAXWELL 3D simulation study of electric field distribution in a tissue/tumor model relevant to electrical-pulse-mediated drug delivery. The authors report lower electric field strength in tumor tissue compared with normal cells. They interpret this as potentially increasing tumor susceptibility…

[Psychophysiological indicators for children using mobile phones. Communication 1. Current state of the problem].

Research RF Safe Research Library Jan 1, 2011

This article reviews epidemiological and experimental evidence on electromagnetic radiation from mobile phones in humans and animals. It focuses in detail on potential effects on children. The abstract reports that children are more sensitive to this type of exposure than adults.

Measurement of creatine kinase reaction rate in human brain using magnetization transfer image-selected in vivo spectroscopy (MT-ISIS) and a volume ³¹P/¹H radiofrequency coil in a clinical 3-T MRI system.

Research RF Safe Research Library Jan 1, 2011

This paper describes a new magnetization transfer 31P MRS approach (MT-ISIS) for measuring the creatine kinase forward reaction rate in the human brain using a volume 31P/1H RF coil on a clinical 3-T MRI system. The method aims to reduce acquisition time (30 min), avoid scalp muscle contamination, improve RF…

Selenium supplementation ameliorates static magnetic field-induced disorders in antioxidant status in rat tissues.

Research RF Safe Research Library Jan 1, 2011

This rat study examined whether selenium supplementation modifies antioxidant-related changes associated with sub-acute static magnetic field exposure. The authors report that SMF exposure altered tissue selenium levels and antioxidant enzyme activities in a tissue-specific manner, including decreased selenium and…

Impact of a pulsed electric field on damage of plant tissues: effects of cell size and tissue electrical conductivity.

Research RF Safe Research Library Jan 1, 2011

This experimental and modeling study examined pulsed electric field (PEF) permeabilization in several fruit and vegetable tissues at 293 K using 1000 μs pulses and field strengths of 400 and 1000 V·cm(-1). While electroporation theory predicts greater damage in tissues with larger cells, the authors report this…

Influence of pulsed electric field treatments on the volatile compounds of milk in comparison with pasteurized processing.

Research RF Safe Research Library Jan 1, 2011

The paper evaluates how pulsed electric field (PEF) processing affects milk volatile compounds compared with HTST pasteurization (75 °C, 15 s). GC-MS detected 37 volatiles and reported some compositional differences between PEF and pasteurized milk, including increased aldehydes and lower methyl ketones with PEF.…

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.…

Impact of a static magnetic field on the electricity production of Shewanella-inoculated microbial fuel cells.

Research RF Safe Research Library Jan 1, 2011

This study investigated how exposure to a static magnetic field affects electricity production in Shewanella-inoculated microbial fuel cells across different reactor configurations. A 100 mT field was reported to increase maximum voltage and the effect was described as immediate and reversible, with possible adverse…

Transient and steady-state magnetic fields induce increased fluorodeoxyglucose uptake in the rat hindbrain.

Research RF Safe Research Library Jan 1, 2011

This animal PET study examined whether a weak 60-Hz magnetic field alters brain glucose utilization in rats. The abstract reports increased FDG uptake in hindbrain voxels when a 2.5-G field was oriented orthogonally to the sagittal plane, but not when field direction varied randomly. Distinct activation effects were…

Human keratinocytes in culture exhibit no response when exposed to short duration, low amplitude, high frequency (900 MHz) electromagnetic fields in a reverberation chamber.

Research RF Safe Research Library Jan 1, 2011

This in vitro study exposed normal human epidermal keratinocytes to non-thermal 900 MHz electromagnetic fields in a mode-stirred reverberation chamber under two short-duration conditions. Microarray analysis found only limited gene modulation (20 genes) with small expression ratios and no shared genes across…

Effects of low frequency electromagnetic fields on the chondrogenic differentiation of human mesenchymal stem cells.

Research RF Safe Research Library Jan 1, 2011

This in vitro study examined whether extremely low-frequency magnetic fields affect chondrogenic differentiation of human mesenchymal stem cells in pellet culture. Cells exposed for 3 weeks to a homogeneous sinusoidal 5 mT magnetic field showed increased collagen type II expression (significant at passage 6) and…

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…

Effect of external normal and parallel electric fields on 180° ferroelectric domain walls in PbTiO₃.

Research RF Safe Research Library Jan 1, 2011

This modeling study applies uniform electric fields parallel and normal to 180° ferroelectric domain walls in PbTiO3 and computes equilibrium structures using anharmonic lattice statics. The authors report that electric fields can substantially increase domain wall thickness and identify a critical field Ec above…

Evaluation of magnetic resonance safety of veterinary radiofrequency identification devices at 1 T.

Research RF Safe Research Library Jan 1, 2011

This study evaluated MRI safety parameters for three commercial veterinary RFID microchips at 1 T, assessing movement forces, heating, artifacts, and device function. Translation and torque were reported to be larger than expected from normal activity, but no significant heating was observed and microchip function…

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…

Ohmic heating of peaches in the wide range of frequencies (50 Hz to 1 MHz).

Research RF Safe Research Library Jan 1, 2010

This engineering/food science study examined ohmic heating of peaches at 60 V/cm using bipolar pulses across frequencies from 50 Hz to 1 MHz. Heating time to a target temperature and multiple electrical properties were frequency-dependent, particularly for intact tissue. The authors report faster electro-thermal…

Disintegration efficiency of pulsed electric field induced effects on onion (Allium cepa L.) tissues as a function of pulse protocol and determination of cell integrity by ¹H-NMR relaxometry.

Research RF Safe Research Library Jan 1, 2010

This experimental study examined how pulsed electric field (PEF) processing parameters affect cell membrane rupture in onion tissue disks, using ion leakage as the primary integrity measure. Disintegration efficiency increased with field strength up to 500 V/cm and varied with pulse width, pulse number, and…

Critical electric field strengths of onion tissues treated by pulsed electric fields.

Research RF Safe Research Library Jan 1, 2010

This experimental study examined how pulsed electric fields affect onion tissue integrity and texture across different field strengths and pulse counts. It reports distinct critical field strengths for plasma membrane versus tonoplast membrane breakdown, with higher thresholds needed for tonoplast disruption. Effects…

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…

← Prev Page 53 / 60 Next →