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Hyperthermic effects of dissipative structures of magnetic nanoparticles in large alternating magnetic fields.

Research RF Safe Research Library Jan 1, 2011

This paper addresses heat dissipation mechanisms of magnetic nanoparticles used in targeted hyperthermia under large alternating magnetic fields. Using numerical comparisons, it reports additional features in relaxation loss for rotatable superparamagnetic nanoparticles and field-induced formation of oriented…

Isolated Atrial Lead Conduction Delay following Right Atrial Radiofrequency Maze Procedure.

Research RF Safe Research Library Jan 1, 2011

This case report describes a 60-year-old man with a dual-chamber implantable cardioverter defibrillator who underwent septal myectomy and a right atrial radiofrequency maze procedure. Following surgery, a persistent delay in atrial sensing was observed. The authors attribute this most likely to iatrogenic right…

Fuzzy mobile-robot positioning in intelligent spaces using wireless sensor networks.

Research RF Safe Research Library Jan 1, 2011

This engineering study develops and experimentally evaluates a fuzzy-logic method for locating mobile robots in an intelligent space using wireless sensor networks. Localization relies on inter-node range measurements estimated from RF signal strength attenuation, which the authors describe as noisy and unreliable.…

Historical building monitoring using an energy-efficient scalable wireless sensor network architecture.

Research RF Safe Research Library Jan 1, 2011

This engineering paper describes low-power wireless sensor nodes and a cluster-based dynamic-tree hierarchical WSN architecture for monitoring historical buildings and wooden artifacts for early pest detection. The authors report simulation and demonstration results indicating improved scalability and reliability…

Response identification in the extremely low frequency region of an electret condenser microphone.

Research RF Safe Research Library Jan 1, 2011

This engineering study describes an experimental setup using a small electret condenser microphone connected to a notebook/PC to detect extremely low frequency signals. Using a small air cell made from a drilled DVD plate with a speaker and microphone on opposite sides, the microphone captured signals in the 0.5–20…

[Time effect of sinusoidal electromagnetic field on enhancing the maturation and mineralization of osteoblasts in vitro].

Research RF Safe Research Library Jan 1, 2011

This in vitro study exposed newborn rat calvarial osteoblasts to 50 Hz sinusoidal electromagnetic fields at 1.8 mT for different daily exposure times (0.5–3.0 h). The authors report inhibited osteoblast proliferation at longer exposure times, alongside increased differentiation markers (ALP activity) and…

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…

A radiofrequency coil to facilitate B₁⁺ shimming and parallel imaging acceleration in three dimensions at 7 T.

Research RF Safe Research Library Jan 1, 2011

This paper reports the development of a 15-channel transmit-receive RF coil for 7 T human brain MRI, using a hybrid decoupling approach to support element placement along three axes. The design is presented as enabling B1+ shimming and parallel imaging acceleration in three dimensions, with reported isolation and…

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…

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…

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…

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…

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