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Radio frequency induced heating of an insulated wire during magnetic resonance imaging.

Research RF Safe Research Library Jan 1, 2016

This engineering study investigated RF-induced power deposition near straight insulated leads in an MRI context under different incident electric field profiles. Using 3-D electromagnetic simulations, the authors compared simulation-derived power deposition with implant model predictions. For the setups examined,…

Variation of radio frequency induced power deposition due to second surrounding tissue.

Research RF Safe Research Library Jan 1, 2016

This engineering study investigated RF-induced power deposition from insulated leads of different lengths positioned near two surrounding tissues. The authors report that both the electromagnetic lead models and the resulting power deposition depended strongly on the electrical properties of both tissues. Using a…

Improving resolution of robotic capsule locomotion using dynamic electromagnetic field.

Research RF Safe Research Library Jan 1, 2016

This engineering conference paper describes a method for controlling the locomotion of swallowable wireless capsule endoscopy devices using a dynamic magnetic field generated by external coils. A permanent magnet embedded in the capsule is manipulated by adjusting external field strengths to maintain equilibrium for…

[Electromagnetic radiation of non-thermal intensity and short exposition as a sub-threshold irritant for the central nervous system].

Research RF Safe Research Library Jan 1, 2013

This article presents a generalization and analysis of the author's long-term materials on brain responses to low-intensity electromagnetic radiation (~500 microW/cm2, continuous or pulsed) after short exposure (~30 minutes). It describes experimental results at the level of single neurons, brain formations, and the…

Specific absorption rate variation in a brain phantom due to exposure by a 3G mobile phone: problems in dosimetry.

Research RF Safe Research Library Jan 1, 2013

This paper describes a SAR measurement system for a 3G mobile phone (1718.5 MHz) using brain phantom material in a Perspex box sized to a small rat volume, with induced fields measured at multiple locations. SAR was computed from induced-field measurements and also estimated experimentally via temperature rise, with…

Epidemiological characteristics of mobile phone ownership and use in korean children and adolescents.

Research RF Safe Research Library Jan 1, 2013

This cross-sectional analysis used three Korean databases (2008–2011; n=21,693) to describe mobile phone ownership and use among children and adolescents and how these patterns vary by socioeconomic position. Ownership and use were higher among females, older students, and in 2011 compared with 2008, and the age of…

Simulation of colloidal fouling by coupling a dynamically updating velocity profile and electric field interactions with Force Bias Monte Carlo methods for membrane filtration.

Research RF Safe Research Library Jan 1, 2013

This engineering simulation study models colloidal particle transport and deposition in a membrane filtration channel at a particle volume fraction of 10%. The model couples a dynamically updating crossflow velocity field with particle-particle and particle-membrane interaction potentials (electrostatic double layer…

Analysis of circular wave packets generated by pulsed electric fields.

Research RF Safe Research Library Jan 1, 2012

This physics study analyzes circular wave packets in high Rydberg states produced by applying a pulsed electric field to extreme Stark states. It reports a position-dependent energy gradient that creates a correlation between principal quantum number and spatial coordinate, which appears insensitive to the initial…

Evaporation rate of water as a function of a magnetic field and field gradient.

Research RF Safe Research Library Jan 1, 2012

This experimental study investigated evaporation of pure water placed at different simulated gravity positions within a superconducting magnet producing a large gradient magnetic field. Water evaporation was reported to be faster in the magnetic field than without the field, and the amount evaporated varied by…

[Study on atmospheric VOCs in Gongga Mountain base station].

Research RF Safe Research Library Jan 1, 2012

This study measured atmospheric VOCs at the Gongga Mountain base station using weekly samples collected in 2007 and analyzed by preconcentration plus GC-MS. It reports mean concentrations of TVOCs and NMHCs, describes VOC composition, and uses PCA-based receptor modeling to attribute sources. The authors report…

A robotic assistant for trans-oral surgery: the robotic endo-laryngeal flexible (Robo-ELF) scope.

Research RF Safe Research Library Jan 1, 2012

This paper describes an engineering/clinical tool development effort: the Robotic EndoLaryngeal Flexible (Robo-ELF) Scope System for manipulating flexible endoscopes in laryngeal surgery. The system includes multiple degrees of freedom, a passive positioning arm, and a custom joystick controller enabling one-handed…

Milk processed by pulsed electric fields: evaluation of microbial quality, physicochemical characteristics, and selected nutrients at different storage conditions.

Research RF Safe Research Library Jan 1, 2011

This study evaluated pulsed electric fields (PEF) as a pasteurization method for raw skim and whole milk across multiple treatment intensities and storage conditions. The abstract reports only minor changes in physicochemical properties and small decreases in some composition measures under stronger treatments.…

Nanocrystalline graphite films nucleation by the radio frequency bias pretreatment.

Research RF Safe Research Library Jan 1, 2011

This paper describes an engineering method for nucleating nanocrystalline carbon films on monocrystalline silicon using a combination of microwave and radio frequency plasma-assisted chemical vapor deposition. The approach is demonstrated via deposition of nanocrystalline diamond after a seeding step and growth of…

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.…

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.…

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…

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.…

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…

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…

[Female genital toxicities of high-frequency electromagnetic field on rats].

Research RF Safe Research Library Jan 1, 2009

This rat study examined sub-chronic exposure to a 30 MHz electromagnetic field at 0–1600 V/m for 8 hours/day, 5 days/week, over 56 days. The authors report no change in ovarian wet weight, but dose-related changes in estrous cycle timing, reproductive hormones (higher LH and lower E2 at higher exposures), and ovarian…

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…

Greyscale intravascular ultrasound and IVUS-radiofrequency tissue characterisation to improve understanding of the mechanisms of coronary stent thrombosis in drug-eluting stents.

Research RF Safe Research Library Jan 1, 2008

This review describes proposed mechanical causes of drug-eluting stent thrombosis and notes that many are identifiable by greyscale intravascular ultrasound (IVUS). It highlights that evidence linking specific IVUS findings to stent thrombosis remains uncertain because relatively few stent thrombosis cases have been…

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…

[Operational aspects of risk perception in the electromagnetic fields exposition].

Research RF Safe Research Library Jan 1, 2007

This study reports on symptomatology and risk perception among 45 people living near power-lines in the Benevento area. Although measured electric and magnetic fields were described as being within the normal range, participants reported symptoms mainly in subjective and behavioural domains. The authors argue that…

Dependence of RF heating on SAR and implant position in a 1.5T MR system.

Research RF Safe Research Library Jan 1, 2007

This phantom study measured RF-induced heating of a stainless steel humerus implant during 1.5T MR imaging while varying SAR, implant angle to B0, and implant position in the RF coil. Temperature rise at implant tips increased linearly with SAR, with larger rises when the implant was parallel to B0. Heating decreased…

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