Read by QxMD icon Read

Electromagnetic field

T J Hilsabeck, J A Frenje, J D Hares, C W Wink
A time-resolved detector concept for the magnetic recoil spectrometer for time-resolved measurements of the NIF neutron spectrum is presented. The measurement is challenging due to the time spreading of the recoil protons (or deuterons) as they transit an energy dispersing magnet system. Ions arrive at the focal plane of the magnetic spectrometer over an interval of tens of nanoseconds. We seek to measure the time-resolved neutron spectrum with 20 ps precision by manipulating an electron signal derived from the ions...
November 2016: Review of Scientific Instruments
Wenzhe Mao, Peng Yuan, Jian Zheng, Weixing Ding, Hong Li, Tao Lan, Adi Liu, Wandong Liu, Jinlin Xie
A compact and lightweight support platform has been used as a holder for the interferometer system on the Keda Torus eXperiment (KTX), which is a reversed field pinch device. The vibration caused by the interaction between the time-varying magnetic field and the induced current driven in the metal optical components has been measured and, following comparison with the mechanical vibration of the KTX device and the refraction effect of the ambient turbulent air flow, has been identified as the primary vibration source in this case...
November 2016: Review of Scientific Instruments
Zichao Li, Hong Li, Cui Tu, Jintong Hu, Wei You, Bing Luo, Mingsheng Tan, Yolbarsop Adil, Yanqi Wu, Biao Shen, Bingjia Xiao, Ping Zhang, Wenzhe Mao, Hai Wang, Xiaohui Wen, Haiyang Zhou, Jinlin Xie, Tao Lan, Adi Liu, Weixing Ding, Chijin Xiao, Wandong Liu
In a reversed field pinch device, the conductive shell is placed as close as possible to the plasma so as to balance the plasma during discharge. Plasma instabilities such as the resistive wall mode and certain tearing modes, which restrain the plasma high parameter operation, respond closely with conditions in the wall, in essence the eddy current present. Also, the effect of eddy currents induced by the external coils cannot be ignored when active control is applied to control instabilities. One diagnostic tool, an eddy current probe array, detects the eddy current in the composite shell...
November 2016: Review of Scientific Instruments
L R Benedetti, C Trosseille, J P Holder, K Piston, D Hargrove, D K Bradley, P Bell, J Raimbourg, M Prat, L A Pickworth, S F Khan
Gain can vary across the active area of an x-ray framing camera by a factor of 4 (or more!) due to the voltage loss and dispersion associated with pulse transmission in a microstripline-coated microchannel plate. In order to make quantitative measurements, it is consequently important to measure the gain variation ("flat field"). Moreover, because of electromagnetic cross talk, gain variation depends on specific operational parameters, and ideally a flat field would be obtained at all operating conditions. As part of a collaboration between Lawrence Livermore National Laboratory's National Ignition Facility and the Commissariat à l'Énergie Atomique, we have been able to evaluate the consistency of three different methods of measuring x-ray flat fields...
November 2016: Review of Scientific Instruments
Necati Gökmen, Sabri Erdem, Kadir Atilla Toker, Elvan Öçmen, Başak Ilgım Gökmen, Ahmet Özkurt
OBJECTIVE: In this study, we conducted a numerical analysis of exposure to electromagnetic fields (EMFs) in a hospital's intensive care unit that is one of the most crucial one in terms of hazardous areas among all service units. This is a new study for measuring exposure to EMFs in an intensive care unit as well as other healthcare services in Turkey. METHODS: We measured the EMFs in the intensive care unit with a SRM-3006 (selective radiation metre), which was used for measurement of the absolute and the limit values of high frequency EMFs...
October 2016: Turkish Journal of Anaesthesiology and Reanimation
Antonio Fasano, Prof Emeritus, Luca Anfuso Md, Stefano Bozzi Md, Claudio Pandozi Prof
BACKGROUND: Radiofrequency ablation is extensively used to achieve pulmonary veins isolation for the cure of atrial fibrillation. Luminal esophageal temperature can be monitored by means of suitable probes to prevent the onset of lesions. OBJECTIVE: To compute the thermal field generated by the ablation, to investigate the interaction between the electromagnetic field and the probe sensors, and to provide a safe interpretation of the temperature detected by the probe, supported by clinical data...
June 2016: Journal of Atrial Fibrillation
Stefano Mossetti, Daniela de Bartolo, Ivan Veronese, Marie Claire Cantone, Cristina Cosenza, Elisa Nava
International and national organizations have formulated guidelines establishing limits for occupational and residential electromagnetic field (EMF) exposure at high-frequency fields. Italian legislation fixed 20 V/m as a limit for public protection from exposure to EMFs in the frequency range 0.1 MHz-3 GHz and 6 V/m as a reference level. Recently, the law was changed and the reference level must now be evaluated as the 24-hour average value, instead of the previous highest 6 minutes in a day. The law refers to a technical guide (CEI 211-7/E published in 2013) for the extrapolation techniques that public authorities have to use when assessing exposure for compliance with limits...
December 1, 2016: Radiation Protection Dosimetry
E Mattei, F Censi, G Calcagnini, R Falsaperla, E Genovese, A Napolitano, V Cannatà
PURPOSE: The effect of the movement near the MRI scanner bore for people with a pacemaker (PM) or an implantable cardioverter defibrillator (ICD) is experimentally evaluated and discussed. METHODS: The authors performed in vitro measurements on a saline-filled human-shaped phantom (male, 170 cm height), equipped first with an MR-conditional PM (bicameral configuration, DDD programming), then with an MR-conditional ICD (biventricular configuration, detection algorithms enable but shock delivery disable)...
December 2016: Medical Physics
Prithwish K Nandi, Zdenek Futera, Niall J English
Given the fundamental role of water in governing the biochemistry of enzymes, and in regulating their wider biological activity (e.g., by local water concentration surrounding biomolecules), the influence of extraneous electric and electromagnetic (e/m) fields thereon is of central relevance to biophysics and, more widely, biology. With the increase in levels of local and atmospheric microwave-frequency radiation present in modern life, as well as other electric-field exposure, the impact upon hydration-water layers surrounding proteins, and biomolecules generally, becomes a particularly pertinent issue...
November 28, 2016: Journal of Chemical Physics
Hua Yu Feng, Feng Luo, Raul Arenal, Luc Henrard, Fernando García, Gaspar Armelles, Alfonso Cebollada
Here we present a novel active system, which combines the plasmon resonance enhancement of the magneto-optical activity in magnetoplasmonic nanostructures and the strong electromagnetic field localization of split ring resonators. The structures consist of a gold split ring resonator placed on top of a gold nanoring in the section of which a Co nanodot is inserted. By placing the split ring gap on top of the nanodot, and continuously varying the split ring gap opening, we are able to tune and enhance the electromagnetic field intensity in the Co nanodot, as confirmed experimentally by EELS and numerically using DDA simulation methods...
December 1, 2016: Nanoscale
Minglin Yang, Yueqian Wu, Kuan Fang Ren, Xinqing Sheng
Due to special characteristics of nondiffraction and self reconstruction, the Bessel beams have attracted wide attention in optical trapping and appear to be a dramatic alternative to Gaussian beams. We present in this paper an efficient approach based on the surface integral equations (SIE) to compute the radiation pressure force (RPF) exerted on arbitrary shaped homogeneous particles by high-order Bessel vortex beam (HOBVB). The incident beam is described by vector expressions perfectly satisfy Maxwell's equations...
November 28, 2016: Optics Express
Wu-Chao Zhai, Tie-Zhu Qiao, Dong-Jin Cai, Wen-Jie Wang, Jing-Dong Chen, Zhi-Hui Chen, Shao-Ding Liu
Third-harmonic generation with metallic or dielectric nanoparticles often suffer from, respectively, small modal volumes and weak near-field enhancements. This study propose and demonstrate that a metallic/dielectric hybrid nanostructure composed of a silver double rectangular nanoring and a silicon square nanoplate can be used to overcome these obstacles for enhanced third-harmonic generation. It is shown that the nonradiative anapole mode of the Si plate can be used as a localized source to excite the dark subradiant octupole mode of the Ag ring, and the mode hybridization leads to the formation of an antibonding and a bonding subradiant collective mode, thereby forming anticrossing double Fano resonances...
November 28, 2016: Optics Express
Ari T Friberg, Tero Setälä
The coherence theory of random, vector-valued optical fields has been of great research interest in recent years. In this work we formulate the foundations of electromagnetic coherence theory both in the space-time and space-frequency domains, with particular emphasis on various types of optical interferometry. Analyzing statistically stationary, two-component (paraxial) electric fields in the classical and quantum-optical contexts we show fundamental connections between the conventional (polarization) Stokes parameters and the associated two-point (coherence) Stokes parameters...
December 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Lei Zhang
The phaseless inverse scattering of optical or electromagnetic waves from unbounded fractally corrugated surfaces are taken into account. The main characteristics of this inverse scattering problem are that only the phaseless scattered field is measured and the incident field is a tapered wave. In the previous recent works of the authors about the inverse scattering of rough surfaces, the cases of the Dirichlet boundary condition were considered [Inverse Prob.32, 085002 (2016)INPEEY0266-561110.1088/0266-5611/32/8/085002; Inverse Probl...
December 1, 2016: Journal of the Optical Society of America. A, Optics, Image Science, and Vision
Zhengping Fu, Masashi Yamaguchi
Coherent excitation and control of lattice motion by electromagnetic radiation in optical frequency range has been reported through variety of indirect interaction mechanisms with phonon modes. However, coherent phonon excitation by direct interaction of electromagnetic radiation and nuclei has not been demonstrated experimentally in terahertz (THz) frequency range mainly due to the lack of THz emitters with broad bandwidth suitable for the purpose. We report the experimental observation of coherent phonon excitation and detection in GaAs using ultrafast THz-pump/optical-probe scheme...
December 1, 2016: Scientific Reports
G N Tayupova, A R Saitgareeva, A R Baitimerov, O S Levin
This review presents the results of studies investigating the effects of transcranial magnetic stimulation (TKMS) on motor and non-motor symptoms of Parkinson's disease (PD). It has been found that TKMS reduces the severity of both motor and non-motor disorders without causing serious side-effects. Magnetic field therapy can be combined with pharmacological and non-drug therapies, including the use of dopaminergic therapy, antidepressants and anti-dementia drugs, as well as stereotactic operations. It is necessary to continue the study of the influence of TKMS on the severity of PD symptoms using different electromagnetic characteristics...
2016: Zhurnal Nevrologii i Psikhiatrii Imeni S.S. Korsakova
Sagnik Basuray, Avinash Pathak, Sangho Bok, Biyan Chen, Steven C Hamm, Cherian J Mathai, Suchismita Guha, Keshab Gangopadhyay, Shubhra Gangopadhyay
Classical methods for enhancing the electromagnetic field from substrates for spectroscopic applications, such as surface-enhanced Raman spectroscopy (SERS), have involved the generation of hotspots through directed self-assembly of nanoparticles or by patterning nanoscale features using expensive nanolithography techniques. A novel large-area, cost-effective soft lithographic technique involving glancing angle deposition (GLAD) of silver on polymer gratings is reported here. This method produces hierarchical nanostructures with high enhancement factors capable of analyzing single-molecule SERS...
December 1, 2016: Nanotechnology
Sarah J Starkey
The Advisory Group on Non-ionising Radiation (AGNIR) 2012 report forms the basis of official advice on the safety of radiofrequency (RF) electromagnetic fields in the United Kingdom and has been relied upon by health protection agencies around the world. This review describes incorrect and misleading statements from within the report, omissions and conflict of interest, which make it unsuitable for health risk assessment. The executive summary and overall conclusions did not accurately reflect the scientific evidence available...
December 1, 2016: Reviews on Environmental Health
Hui Liu, Jun Zhou, Lianbing Gu, Yunxia Zuo
Neuropathic pain is usually defined as a chronic pain state caused by peripheral or central nerve injury as a result of acute damage or systemic diseases. It remains a difficult disease to treat. Recent studies showed that the frequency of action potentials in nociceptive afferents is affected by the activity of hyperpolarization-activated cyclic nucleotide-gated cation channels (HCN) family. In the current study, we used a neuropathy rat model induced by chronic constriction injury (CCI) of sciatic nerve to evaluate the change of expression of HCN1/HCN2 mRNA in peripheral nerve and spinal cord...
November 25, 2016: Oncotarget
Ola Ahmed El-Gohary, Mona Abdel-Azeem Said
There are considerable public concerns about the relationship between mobile phone radiation and human health. The present study assesses the effect of electromagnetic field (EMF) emitted from a mobile phone on the immune system in rats and the possible protective role of vitamin D. Rats were randomly divided into six groups: Group I: control group; Group II: received vitamin D (1000 IU/kg/day) orally; Group III: exposed to EMF 1 h/day; Group IV: exposed to EMF 2 h/day; Group V: exposed to EMF 1 h/day and received vitamin D (1000 IU/kg/day); Group VI: exposed to EMF 2 h/day and received vitamin D (1000 IU/kg/day)...
September 5, 2016: Canadian Journal of Physiology and Pharmacology
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"