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The impact of weak permanent magnetic field (PMF) with magnetic flux density of 185-650 μT on activities of antioxidant enzymes in 5-day-old radish ( Raphanus sativus L. var. radicula D.C.) seedlings, cv, Rosovo-krasnyi s belym konchikom was demonstrated. In the range of 185-325 μT PMF suppressed superoxide dismutase (SOD) activity in seedling grown in darkness and catalase (CAT) grown in both darkness and light. At the same values of magnetic flux density, all fractions of guaiacol peroxidase were activated and MDA accumulation was enhanced. At the higher values of magnetic flux density, SOD was activated in seedlings grown in darkness and CAT was activated in seedlings grown in both darkness and light. Other indices decreased or remained unchanged. It was concluded that PMF action depends on its intensity: at its low values, antioxidant enzymes are inhibited and at high values - activated. [ABSTRACT FROM AUTHOR]

A detailed investigation on geoeffectiveness of CMEs associated with DH-type-II bursts observed during 1997-2008 is presented. The collected sample events are divided into two groups based on their association with CMEs related to geomagnetic storms Dst ≤-50nT, namely, (i) geoeffective events and (ii) nongeoeffective events. We found that the geoeffective events have high starting frequency, low ending frequency, long duration, wider bandwidth, energetic flares, and CMEs than nongeoeffective events. The geoeffective events are found to have intense geomagnetic storm with mean Dst index (-150 nT). There exists good correlation between the properties of CMEs and flares for geoeffective events, while no clear correlation exists for nongeoeffective events. There exists a weak correlation for geoeffective events between (i) CME speed and Dst index (R = -0.51) and good correlation between (i) CME speed and solar wind speed (R = 0.60), (ii) Dst index and solar wind speed (R = -0.64), and (iii) Dst index and southward magnetic field component (Bz) (R = 0.80). From our study we conclude that the intense and long duration southward magnetic field component (Bz) and fast solar wind speed are responsible for geomagnetic storms, and the geomagnetic storms weakly depend on CME speed. About 22% (50/230) of the DH-type-II bursts are associated with geomagnetic storms. Therefore the DH-type-II bursts associated with energetic flares and CMEs are good indicator of geomagnetic storms. [ABSTRACT FROM AUTHOR]

Abstract: Background and Purpose: Fine-mesh braided, stent-like structures (flow diverters) have been proposed for treatment of brain aneurysms. To date, the safety of performing magnetic resonance imaging (MRI) in patients with these implants is unknown. Therefore, the purpose of this study was to evaluate MRI issues at 3-T for a new flow-diverting implant used to treat brain aneurysms. Methods: The Surpass NeuroEndoGraft (Surpass Medical, Ltd., Tel Aviv, Israel) underwent evaluation for magnetic field interactions, MRI-related heating and artifacts using standardized techniques. Magnetic field interactions were assessed for this implant with regard to translational attraction (i.e., using the deflection angle technique) and torque (qualitative assessment method). MRI-related heating was evaluated by placing the implant in a gelled-saline-filled, head/torso phantom and performing MRI using a transmit/receive radiofrequency body coil at a whole-body-averaged specific absorption rate of 2.9 W/kg for 15 min. Artifacts were characterized using T1-weighted, spin echo (SE) and gradient echo (GRE) pulse sequences. Results: The Surpass NeuroEndoGraft exhibited minor magnetic field interactions (21° deflection angle and no torque), which were acceptable from a safety consideration. Heating was not substantial, with the highest temperature change being 2.3°C (background temperature rise without the implant was 1.5°C). Artifacts may create issues if the area of interest is in the same area or close to this implant. Conclusions: The findings demonstrated that it would be acceptable for patients with this next-generation, flow-diverting implant to undergo MRI at 3-T or less. [Copyright &y& Elsevier]

Abstract: Magnetoencephalography (MEG) beamformer analyses use spatial filters to estimate neuronal activity underlying the magnetic fields measured by the MEG sensors. MEG “virtual electrodes” are the outputs of beamformer spatial filters. The present study aimed to test the hypothesis that MEG virtual electrodes can replicate the findings from intracortical “depth” electrode studies relevant to the processing of the temporal envelopes of sounds [e.g. Nourski et al. (2009) “Temporal envelope of time-compressed speech represented in the human auditory cortex,” J. Neurosci. 29:15564–15574]. Specifically we aimed to determine whether it is possible to use non-invasive MEG virtual electrodes to characterise the representation of temporal envelopes of 6-Hz sinusoidal amplitude modulation (SAM) and speech using both auditory evoked fields (AEFs) and patterns of power changes in high-frequency (>70Hz) bands. MEG signals were analysed using a location of interest (LOI) approach by seeding virtual electrodes in the left and right posteromedial Heschl''s gyri. AEFs showed phase-locking to the temporal envelope of SAM and speech stimuli. Time-frequency analyses revealed no clear differences in high gamma power between the pre-stimulus baseline and the post-stimulus presentation periods. Nevertheless the patterns of changes in high gamma power were significantly correlated with the temporal envelopes of 6-Hz SAM and speech in the majority of participants. The present study reveals difficulties in replicating clear augmentations in high gamma power changes using MEG virtual electrodes cf. intracortical “depth” electrode studies (Nourski et al., 2009). [Copyright &y& Elsevier]

The purpose of this study was to determine whether exposure to an extremely low-frequency magnetic field (ELF-MF, 50 Hz) affects the outcome of postischemic damage in the hippocampus of Mongolian gerbils. After 10-min bilateral carotid occlusion, the gerbils were continuously exposed to ELF-MF (average magnetic induction at the center of the cage was 0.5 mT) for 7 days. The impact of ELF-MF was estimated immediately (the 7th day after reperfusion) and 7 days after cessation of exposure (the 14th day after reperfusion) compared with ischemic gerbils without ELF-MF exposure. Applying stereological methods, histological evaluation of changes in the hippocampus was done for determining its volume, volume densities of degenerating neurons and astrocytes, as well as the number of microglial cells per unit area. ELF-MF per se did not induce any morphological changes, while 10-min global cerebral ischemia led to neuronal death, especially in CA1 region of the hippocampus, as expected. Ischemic gerbils exposed to ELF-MF had significantly a lower degree of cell loss in the examined structure and greater responses of astrocytes and microglial cells than postischemic gerbils without exposure on the seventh day after reperfusion (immediate effect of ELF-MF). Similar response was observed on the 14th day after reperfusion (delayed effect of ELF-MF); however, differences in measured parameters were low and insignificant. Applied ELF-MF has possible neuroprotective function in the hippocampus, as the most sensitive brain structure in the model of global cerebral ischemia, through reduction of neuronal death and activation of astrocytes and microglial cells. [ABSTRACT FROM AUTHOR]

Abstract: Mobile genetic elements represent an important source of mutation and genomic instability, and their activity can be influenced by several chemical and physical agents. In this research we address the question whether exposure to extremely low-frequency pulsed magnetic fields (EMF-PMF) could affect the mobility of the human LINE-1RP retrotransposon. To this purpose, an in vitro retrotransposition assay was used on human neuroblastoma BE(2) cells exposed for 48h to 1mT, 50Hz PMF, or sham-exposed. Moreover, since it is well known that retrotransposition causes DNA double-strand breaks (DSB), an estimation of γ-H2AX foci, which is a marker of DNA DSB, was carried out on PMF- and sham-exposed samples. The results show that PMF-exposed cells had a lower number of both retrotransposition events and DNA DSB compared with sham-exposed samples. These results suggest that exposure to PMF can interfere with retrotransposition activity by inducing a decrease of retrotransposition events. [Copyright &y& Elsevier]

The aim of this study is to determine the effects of magnetic field via cell phones on some blood parameters and neurons in the brain of rats. Animals have been classified into three groups: control, Magnetic Field (MF), and F2 groups. Throughout this study, cell phones were placed on the wall of the cages. Rats were exposed to the effects of cell phones during prenatal and postnatal periods until they were 80 days old. During the study, the exposure procedure of rats was that the phone was in standby mode for a whole day and in talking mode for 30 min per day. The waves of cell phones caused an increased blood glucose level from 96.52 ± 5.64 mg/dl to 132.14 ± 5.93 mg/dl and an increased serum protein level from 131.14 ± 6.19 mg/dl to 319.29 ± 6.73 mg/dl compared to control. Statistically, significant differences wasn't observed in the blood cholesterol concentration between the groups compared to the control. Weekly weight gain decreased in all groups compared to the control. MF exposure decreased pyramidal neuron numbers 51.15% and increased ischemic neuron numbers 73% at cortex region of brain. In addition, vascular dilatations have increased clearly in group F2.Whereas the procedure of MF did not have any effects on hippocampal pyramidal cell numbers, magnetic fields increased the amount of ischemic neurons three-fold compared to the control. In conclusion, MF affected some biochemical parameters, especially the cortex region of the brain. [ABSTRACT FROM AUTHOR]

We investigated the comparative effects of 4 and 60 Hz magnetic fields on pentylenetetrazole (PTZ)-induced seizure in mice. For this study, we measured the latent time to seizure, seizure duration, and lethality induced by PTZ in mice exposed to 4 and 60 Hz magnetic fields (MF) for 30 min. Compared to sham-exposed controls, the latent time to tail twitching and seizure in the 4 Hz MF group was significantly decreased while the latent time to seizure in the 60 Hz MF group was significantly increased. The seizure duration in the 4 Hz MF group was significantly decreased while that in the 60 Hz MF group was significantly increased. More importantly, while the mice exposed to a 60 Hz MF experienced significantly increased lethality after seizure convulsion, those exposed to a 4 Hz MF showed no lethality, with a shortening of the duration of seizure. This beneficial effect of a 4 Hz MF on seizure has the same implication as the anti-oxidative effects of a 4 Hz MF observed in our previous work. The results of our current and previous works indicate that a 4 Hz MF may be used as a therapeutic physical agent for the treatment of oxidative stress-induced diseases, including seizure, with or without chemical drugs. [ABSTRACT FROM AUTHOR]

In this study, human median nerve was exposed to power frequency magnetic fields in order to provide clarification for possibly changeable nerve conduction mechanism. The nerve was exposed to 50 Hz magnetic field by utilizing a special Helmholtz applicator. The experiments were carried out with six healthy human-volunteers. Median motor distal amplitude/proximal amplitude ratios were recorded from adult human median nerve pre-exposure, during, and post-exposure to a 50 Hz, 1 mT magnetic field. The result of 18 measurements shows that median motor distal amplitude/proximal amplitude ratio significantly decreases in pre-exposure state as compare to post exposure of which. The results of this study may be useful for some nerve rehabilitation, excitation, and stimulation in more effective/safe physical therapy. Additionally, 50 Hz, 1 mT sinusoidal magnetic field should not be recognizing as safe for conduction mechanism on a nerve. These mechanisms would be cleared by new advanced engineering models in other future works. [ABSTRACT FROM AUTHOR]

Purpose: Electromagnetic fields have various effects on intracellular calcium levels, free oxygen radicals and various enzymes. The platelet activation pathway involves an increase in intracellular calcium levels and protein kinase C activation; and free oxygen radicals play a mediating role in this pathway. This study investigated whether 1 mT and 6 mT, 50 Hz magnetic fields had any effects on platelet aggregation. Materials and Methods: Blood from healthy volunteers was anticoagulated with either citrate or heparin. Each sample was divided in half and assigned to exposure and control groups. Platelet rich plasma samples in the exposure group were exposed to a 1 mT or a 6 mT, 50 Hz magnetic field for 1.5 or 1 h, respectively. The samples from both exposure and control groups were simultaneously evaluated using a modified optical aggregometer. Adenosine-diphosphate, collagen, and epinephrine were used as inducing agents. The slopes of the aggregation curve, the maximum values and the areas under the curves were recorded and compared. Results: A significant effect was observed only in the 1 mT-citrate group. It was found that magnetic field exposure significantly increased the maximum values and slopes of the collagen-induced aggregations. Conclusions: It was found that magnetic field exposure has an activating effect on platelet aggregation. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To determine interhemispheric differences and effect of postmenstrual age (PMA), height, and gender on somatosensory evoked magnetic fields (SEFs) from the primary (SI) and secondary (SII) somatosensory cortices in healthy newborns. Methods: We recorded SEFs to stimulation of the contralateral index finger (right in 46 and left in 12) healthy fullterm newborns and analyzed the magnetic responses with equivalent current dipoles. Results: Activity from both the SI and SII was consistently detectable in the contralateral hemisphere of the newborns during quiet sleep. No significant interhemispheric differences existed in SI or SII response peak latencies, source strengths, or location (n =8, quiet sleep). SI or SII response peak latency or source strength were not significantly affected by PMA, height, or gender. Conclusions: During the neonatal period (PMA 37–44weeks), activity from the contralateral SI and SII can be reliably evaluated with MEG. The somatosensory responses are similar in the left and right hemispheres and no corrections for exact PMA, height, or gender are necessary for interpreting the results. However, the evaluation should be conducted in quiet sleep. Significance: The reproducibility of the magnetic SI and SII responses suggests clinical applicability of the presented MEG method. [Copyright &y& Elsevier]

ABSTRACT The so-called 'Melatonin Hypothesis' proposed that decreased nocturnal production of melatonin (MLT) might explain the increased risk of breast cancer that has been formerly attributed to extremely low-frequency (ELF) magnetic fields (MF) of weak intensity. Although the risk of ELF MF upon breast cancer was later dismissed, repeated reports were published of partial inhibition of MLT secretion in rats under long-term (≥ 4 weeks) exposure to weak ELF MF. Since 2004, however, this topic has not been experimentally studied any more. In the present study, we propose to go back to the MLT hypothesis and apply it to childhood leukemia, for which an increased risk has been robustly associated with residential exposure to ELF MF. Contrary to the original hypothesis, however, we do not consider decreased MLT levels, but disruption of circadian rhythmicity per se as the effector mechanism. Indeed, the role of the circadian timing system in the development of childhood leukemia has been well established. Motivation for going back to the MLT hypothesis comes from recent data that suggest magnetosensory disruption by ELF MF in mammals, and magnetosensitivity in humans, together with current evidence for an influence on circadian rhythmicity from disruption of non-photic sensory stimuli of various natures. We thus suggest further study on circadian rhythmicity in humans (children if possible) under long-term exposure to weak ELF MF. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Migrating birds fly thousands of miles or more, often without visual cues and in treacherous winds, yet keep direction. They employ for this purpose, apparently as a powerful navigational tool, the photoreceptor protein cryptochrome to sense the geomagnetic field. The unique biological function of cryptochrome supposedly arises from a photoactivation reaction involving radical pair formation through electron transfer. Radical pairs, indeed, can act as a magnetic compass; however, the cryptochrome photoreaction pathway is not fully resolved yet. To reveal this pathway and underlying photochemical mechanisms, we carried out a combination of quantum chemical calculations and molecular dynamics simulations on plant (Arabidopsis thaliana) cryptochrome. The results demonstrate that after photoexcitation a radical pair forms, becomes stabilized through proton transfer, and decays back to the protein's resting state on time scales allowing the protein, in principle, to act as a radical pair-based magnetic sensor. We briefly relate our findings on A. thaliana cryptochrome to photoreaction pathways in animal cryptochromes. [ABSTRACT FROM AUTHOR]

Abstract: There has been increasing interest on the possible harmful effects of prenatal exposure to magnetic fields. To investigate the effect of weak intensity magnetic fields on the prenatal brain, pregnant Wistar rats were continuously exposed to one of four intensities (reference: 5–20nT; low 30–50nT; medium 90–580nT; high 590–1200nT) of a complex magnetic field sequence designed to interfere with brain development. As adults, rats exposed to the low-intensity (30–50nT) complex magnetic field displayed impairments in contextual fear learning and showed anomalies in the cytological and morphological development of the hippocampus. In particular, low-intensity exposures resulted in a reduction in overall hippocampal size and promoted subtle dysgenesis of the CA1 and CA3 regions. In contrast, exposure to weaker or stronger intensities of the same complex magnetic field pattern did not interfere with hippocampal development or fear behavior. These findings suggest that prenatal exposure to complex magnetic fields of a narrow intensity window during development can result in subtle but permanent alterations in hippocampal microstructure and function that can have lasting effects on behavior. [Copyright &y& Elsevier]

Anisotropic magnetoresistance and negative magnetoresistance for in-plane fields are compared for the LaAlO 3 /SrTiO 3 interface and the symmetric Nb-doped SrTiO3 heterostructure. Both effects are exceptionally strong in LaAlO3/SrTiO3. We analyze their temperature, magnetic field, and gate voltage dependencies and find them to arise from a Rashba-type spin-orbit coupling with magnetic scatterers that have two contributions to their potential: spin exchange and Coulomb interaction. Atomic spin-orbit coupling is sufficient to explain the small effects observed in Nb-doped SrTi03. These results clarify contradicting transport interpretations in SrTiO3based heterostructures. [ABSTRACT FROM AUTHOR]

Context. We investigated the generation of localized magnetic fields in an ultra-relativistic non-isothermal electron-positron plasma by strong electromagnetic plasmons. Aims. The results obtained can be used to explain the origin of small-scale magnetic fields in the internal shock region of gamma-ray bursts with ultra-relativistic electron positron plasmas. Methods. The generation of magnetic fields was investigated with kinetic Vlasov Maxwell equations. Results. The self-generated magnetic field will collapse for modulation instability, leading to spatially highly intermittent magnetic fluxes, whose characteristic scale is much larger than relativistic plasma skin depth, which in turn is conducive to the generation of the long-life small-scale magnetic fields in the internal shock region of gamma-ray bursts. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To measure neuromagnetic evoked fields in the lumbar spinal canal. Methods: Using a newly developed superconducting quantum interference device (SQUID) fluxmeter, neuromagnetic fields of 5 healthy male volunteers were measured at the surface of the lower back after stimulation of the tibial nerves at the ankles. For validation, we inserted a catheter-type electrode percutaneously in the lumbar epidural space in 2 of the subjects and measured cauda equina action potentials after tibial nerve stimulation. Results: Neuromagnetic fields propagating from the intervertebral foramina into the spinal canal were measured, and the latencies of the magnetic fields corresponded largely with those of the cauda equina action potentials. Conclusions: We successfully measured ascending neuromagnetic fields originating at the nerve root and the cauda equina with high spatial resolution. Future studies will determine whether neuromagnetic field measurement of the lumbar spine can be a useful diagnostic method for the identification of the disordered site in spinal nerves. Significance: We successfully measured neuromagnetic fields in the lumbar spinal canal, which have previously been difficult to verify. Future studies will determine whether neuromagnetic field measurement of the lumbar spine can be a useful diagnostic method for identifying disorders of spinal nerves. [Copyright &y& Elsevier]

this paper describes principles of magnetotherapy as an alternative to classic medicine. The effect of an externally applied pulsed magnetic field for wound healing after trauma will be displayed. Novel design for stimulation coils is presented. [ABSTRACT FROM AUTHOR]

What is the ultimate limit to high fields in superconducting magnets for particle accelerators? In this paper we review the present status of the technology, outlining the main limitations. We first analyse the needed margin for operating a magnet in an accelerator. We then review the relation between current densities, coil widths, and fields in the magnets build so far. The issue of stress and the dependence on the coil lay-out is then discussed: a careful optimization between current density and coil width can be needed to keep the forces and associated strain within acceptable limits. The main issues related to cable lay-out (strand diameter, filament size) are then discussed. We conclude by giving a hint on the requirements on a HTS conductor, and a summary of Nb-Ti and Nb3Sn. [ABSTRACT FROM PUBLISHER]

The Nijmegen High Field Magnet Laboratory (Nijmegen HFML) presently offers to its users 33 T in two 32 mm bore resistive magnets, 32 T in a 50 mm bore resistive magnet and 30 T in a 50 mm bore hybrid magnet. To comply with the users' demand for ever higher magnetic fields without having to resort to hybrid magnets, a new resistive 20+ MW magnet has been designed and is now being constructed, which will deliver 38 T in a 32 mm bore. The magnet consists of five Florida-Bitter coils and one outer Bitter coil. The two innermost coils (A1 and A2, CuAg conductor) are electrically in parallel. The outer coil (E, Cu conductor) has an outer diameter set to 1 m. The length of this coil is about 670 mm and it weighs almost 3000 kg, indicative of the huge amount of conductor material needed for 40 T class resistive magnets. An important issue is the necessity to reduce the slit factor, i.e. the locally high current density in a winding at a slit in a Bitter disk. We therefore decided to implement the modified Weggel stacking scheme for the A, B and C coils, implying a noninteger number of disks per turn, e.g. 11 13/25 for the B coil. Also, a new compact (1.3 m outer diameter, 1.4 m height) housing has been designed, able to withstand the combined stress due to the maximum fault force of 2.1 MN (occurring when the C coil fails) and the effect of 40 bar differential water pressure. The new magnet is expected to be commissioned in the fourth quarter of 2012. [ABSTRACT FROM PUBLISHER]

The aim of this paper is to present an up to date review of the status of the European DIPOle (EDIPO) project—whose objective is to build a new facility to perform both DC and AC tests of large force flow superconductor samples in high magnetic background field (up to \sim12.5 T)—as well as an outlook on the final commissioning of the magnet in CRPP-PSI foreseen for 2012. Concerning the actual status, the results presented focus on the recent steps carried out in the manufacturing of the magnet assembly, in particular the cold mass assembly, its impregnation and the final acceptance tests. Moreover, results are reported regarding the identification and repair of an inter-turn short carried out on EDIPO Pole 1 in the second half of 2010. As far as the commissioning of EDIPO is concerned, an up-to-date report is provided on the preparation of the facility at CRPP (e.g. mechanical structures, high temperature current leads, quench detection, control system, etc.) as well as its acceptance and final commissioning (e.g. magnet reception tests, commissioning program, etc.) [ABSTRACT FROM PUBLISHER]

A benchmarking experiment was conducted to compare strain measurement facilities at the National Institute of Standards and Technology (NIST) and the University of Twente. The critical current of a bronze-route Nb3Sn wire, which was fabricated for the International Thermonuclear Experimental Reactor (ITER), was measured as a function of axial strain and magnetic field in liquid helium at both institutes. NIST used a Walters' spring strain device and University of Twente used a bending beam (“Pacman”) apparatus. The ITER bronze-route wire investigated had a very high irreversible strain limit that allowed comparing data over a wide range of applied strain between -1% and +1%. Similarities of the data obtained by use of the two apparatuses were remarkable, despite the many differences in their design and techniques. [ABSTRACT FROM PUBLISHER]

Many animals rely on Earth's magnetic field for spatial orientation and navigation. However, how the brain receives and interprets magnetic field information is unknown. Support for the existence of magnetic receptors in the vertebrate retina, beak, nose, and inner ear has been proposed, and immediate gene expression markers have identified several brain regions activated by magnetic stimulation, but the central neural mechanisms underlying magnetoreception remain unknown. Here we describe neuronal responses in the pigeon's brainstem that show how single cells encode magnetic field direction, intensity, and polarity; qualities that are necessary to derive an internal model representing directional heading and geosurface location. Our findings demonstrate that there is a neural substrate for a vertebrate magnetic sense. [ABSTRACT FROM AUTHOR]

The effects of time-varying magnetic fields (MF) on humans have been actively investigated for the past three decades. One important unanswered question is the potential for MF exposure to have acute effects on human biology. Different strategies have been used to tackle this question using various physiological, neurophysiological and behavioral indicators. For example, researchers investigating electroencephalography (EEG) have reported that extremely low frequency (ELF, <300 Hz) MF can increase resting occipital alpha rhythm (8-12 Hz). Interestingly, other studies have demonstrated that human motricity can be modulated by ELF MF: a reduction of anteroposterior standing balance or a decrease of physiological tremor intensity have been reported as consequences of exposure. However, the main limitation in this domain lies in the lack of results replication, possibly originating from the large variety of experimental approaches employed. Therefore, the present study aimed to investigate the effects of a 60 Hz, 1,800 μT MF exposure on neurophysiological (EEG) and neuromotor (standing balance, voluntary motor function, and physiological tremor) aspects in humans using a single experimental procedure. Though results from this study suggest a reduction of human standing balance with MF exposure, as well as an increase of physiological tremor amplitude within the frequency range associated with central nervous system contribution, no exposure effect appeared on other investigated parameters (e.g., EEG or voluntary motor control). These results suggest that 1 h of 60 Hz, 1,800 μT MF exposure may modulate human involuntary motor control without being detected in the cortical electrical activity. [ABSTRACT FROM AUTHOR]

Purpose: The issue of whether exposure to environmental power-frequency magnetic fields (MF) has impact on breast cancer development still remains equivocal. Previously, we observed rat strain differences in the MF response of breast tissue, so that the genetic background plays a role in MF effects. The present experiment aimed to elucidate candidate genes involved in MF effects by comparison of MF-susceptible Fischer 344 (F344) rats and MF-insensitive Lewis rats. Materials and methods: Female F344 and Lewis rats were exposed to MF (50 Hz, 100 μT) for two weeks, and a whole genome microarray analysis in the mammary gland tissue was performed. Results: A remarkably decreased α-amylase gene expression, decreases in carbonic anhydrase 6 and lactoperoxidase, both relevant for pH regulation, and an increased gene expression of cystatin E/M, a tumor suppressor, were observed in MF-exposed F344, but not in Lewis rats. Conclusion: The MF-exposed F344 breast tissue showed alterations in gene expression, which were absent in Lewis and may therefore be involved in the MF-susceptibility of F344. Notably α-amylase might serve as a promising target to study MF effects, because first experiments indicate that MF exposure alters the functionality of this enzyme in breast tissue. [ABSTRACT FROM AUTHOR]

Abstract: An increasing number of people worldwide complain that they have become electromagnetic hypersensitive (EHS). We conducted a questionnaire survey of EHS persons in Japan. The aim was to identify electromagnetic fields (EMF) and plausible EMF sources that caused their symptoms. Postal questionnaires were distributed via a self-help group, and 75 participants (95% women) responded. Reported major complaints were “fatigue/tiredness” (85%), “headache”, “concentration, memory, and thinking” difficulty (81%, respectively). Seventy-two per cent used some form of complementary/alternative therapy. The most plausible trigger of EHS onset was a mobile phone base station or personal handy-phone system (37%). Sixty-five percent experienced health problems to be due to the radiation from other passengers’ mobile phones in trains or buses, and 12% reported that they could not use public transportation at all. Fifty-three percent had a job before the onset, but most had lost their work and/or experienced a decrease in income. Moreover, 85.3% had to take measures to protect themselves from EMF, such as moving to low EMF areas, or buying low EMF electric appliances. EHS persons were suffering not only from their symptoms, but also from economical and social problems. [Copyright &y& Elsevier]

We report a comprehensive study of the electrical and magnetotransport properties of nanocrystals of La0.67Ca0.33MnO3 (LCMO) (with size down to 15 nm) and La0.5Sr0.5CoO3 (LSCO) (with size down to 35 nm) in the temperature range 0.3-5K and magnetic fields up to 14 T. The transport, magneto-transport and nonlinear conduction (I -V curves) were analysed using the concept of spin-polarized tunnelling in the presence of Coulomb blockade. The activation energy of transport, Δ, was used to estimate the tunnelling distances and the inverse decay length of the tunnelling wave function (χ) and the height of the tunnelling barrier (ΦB). The magneto-transport data were used to find the magnetic field dependences of these tunnelling parameters. The data taken over a large magnetic field range allowed us to separate out the magnetoresistance (MR) contributions at low temperatures arising from tunnelling into two distinct contributions. In LCMO, at low magnetic field, the transport and MR are dominated by the spin polarization, while at higher magnetic field the MR arises from the lowering of the tunnel barrier by the magnetic field, leading to an MR that does not saturate even at 14 T. In contrast, in LSCO, which does not have substantial spin polarization, the first contribution at low field is absent, while the second contribution related to barrier height persists. The idea of intergrain tunnelling has been validated by direct measurements of the nonlinear I -V data in this temperature range, and the I -V data were found to be strongly dependent on magnetic field. We made the important observation that a gaplike feature (with magnitude ∼EC, the Coulomb charging energy) shows up in the conductance g(V) at low bias for the systems with the smallest nanocrystal size at the lowest temperatures (T ⩽ 0.7 K). The gap closes when the magnetic field and temperature are increased. [ABSTRACT FROM AUTHOR]

The paper describes the cases of 3 female health operators with implanted copper IUDs, developing menometrorrhagia some months after an increase of the working time in a Magnetic Resonance Imaging (MRI) Unit (1.5 T), that progressively disappeared when the previous organization, involving discontinuous work shifts at MRI, was re-established. No known factors possibly related to menometrorrhagia were evidenced in the 3 operators, supporting the hypothesis of a role of the exposure to the electromagnetic fields (EMF) induced by the MRI system in symptoms induction. The possible mechanism remains unsettled, but menometrorrhagia might be triggered by a phlogistic stimulus caused by EMF, possibly the low-frequency currents induced in the wires of the IUD during the movements of the operator inside the static magnetic field generated by the MRI permanent magnet. Until now, the problem of possible interactions between copper IUDs and EMF induced by MRI has been considered in patients undergoing imaging, but the possible risk in MRI Units operators has been largely neglected. To our knowledge, the occurrence of menometrorrhagia is not routinely checked in health surveillance of MRI operators, so these symptoms can pass unnoticed, especially if they are transitory. Therefore, underreporting is rather possible. The cases described here support the need for further research on this topic, especially considering the progressive diffusion of more powerful MRI scanners (3 T and more), and of the interventional magnetic resonance imaging, both potentially involving higher EMF exposures, and a large number of MRI female operators, possibly using IUDs. The possibility that MRI operators with implanted metallic IUDs can be included in the group of 'workers at particular risk' according to the EU Directive 2004/40/EC should be considered. [ABSTRACT FROM AUTHOR]

Magnetotactic bacteria ( MB) are remarkable organisms with the ability to exploit the earth's magnetic field for navigational purposes. To do this, they build specialized compartments called magnetosomes that consist of a lipid membrane and a crystalline magnetic mineral. These organisms have the potential to serve as models for the study of compartmentalization as well as biomineralization in bacteria. Additionally, they offer the opportunity to design applications that take advantage of the particular properties of magnetosomes. In recent years, a sustained effort to identify the molecular basis of this process has resulted in a clearer understanding of the magnetosome formation and biomineralization. Here, I present an overview of MB and explore the possible molecular mechanisms of membrane remodeling, protein sorting, cytoskeletal organization, iron transport, and biomineralization that lead to the formation of a functional magnetosome organelle. [ABSTRACT FROM AUTHOR]

The effect of the external magnetic field has been investigated on the Ll, Lα, Lβ and Lγ production cross sections of Pt and Au elements in the angular range 90°-150° by using an energy dispersive x-ray fluorescence spectrometer. The samples were irradiated by using the gamma rays of 59.537 keV emitted from an ^{241}Am radioisotope source of 100 mCi. The external magnetic fields have been applied two opposite directions and the magnitude of the external magnetic field has been fixed at +0.75 T and -0.75 T. For B=0, Ll and Lα groups in the L x-ray lines are found to be spatially anisotropic, while those in the Lβ and Lγ peaks are isotropic. An enhancement in the differential Ll and Lα production cross sections is observed in the presence of external magnetic field. Integral cross sections for production of Ll, Lα, Lβ and Lγ x-rays were also deduced and were found to be in good agreement with the theoretical values for B=0. [ABSTRACT FROM AUTHOR]

Great development in medicinal, spice, and aromatic plant crops has occurred in Mediterranean countries due to their high added value as a consequence of the reappearance of phitotherapy, among other reasons. The main objective of this study is to determine the effects of magnetic treatment, in addition to the geomagnetic field, on germination of Salvia officinalis L. and Calendula officinalis L. seeds. This objective has a practical application in agricultural science: to obtain the early growth of both plants. Groups of 100 seeds were exposed to a 125 mT stationary magnetic field generated by magnets at different times, whereas the other group of 100 seeds was subjected to a magnetic pre-treatment, and non-exposed seeds were used as control. Germination tests were performed under laboratory conditions. The selected germination parameters were: time for the first seed to germinate (T1), time to reach 10-75% germination (T10, T25, T50, and T75), mean germination time (MGT), and number of germinated seeds (Gmax), all provided by the Seed calculator software package. The germination parameters recorded for Salvia officinalis L. seeds for each treatment and pre-treatment were lower than corresponding control value. Among the various treatments, chronic exposure to 125 mT provided best results; the MGT was significantly reduced compared to control, parameters (T1-T50) were also significantly reduced for most treatments. Results obtained for Calendula officinalis L. seeds showed that germination parameters were reduced, in most cases, for magnetic treatment versus control, and all parameters of germination were reduced for pre-treatment versus control. The best results were obtained from chronic exposure. Results indicated that magnetic field application enhanced germination rate and percentage of germinated seed on the treated group compared to the non-exposed in both cases. [ABSTRACT FROM AUTHOR]

The article offers information on a study conducted in order to determine the impact of effective gravity and magnetic field strengths in plants with special reference to Arabidopsis thaliana. The study has revealed that gravitational and magnetic fields produce synergistic variations in transcriptional profile of plants. It has been discovered that high gradient magnetic fields have significant effect on plants, especially on structural, abiotic stress genes and secondary metabolism genes.

Magnetic field lines in astrophysical plasmas are expected to be frozen-in at scales larger than the ion gyroradius. The rapid reconnection of magnetic-flux structures with dimensions vastly larger than the gyroradius requires a breakdown in the standard Alfvén flux-freezing law. We attribute this breakdown to ubiquitous MHD plasma turbulence with power-law scaling ranges of velocity and magnetic energy spectra. Lagrangian particle trajectories in such environments become "spontaneously stochastic," so that infinitely many magnetic field lines are advected to each point and must be averaged to obtain the resultant magnetic field. The relative distance between initial magnetic field lines which arrive at the same final point depends upon the properties of two-particle turbulent dispersion. We develop predictions based on the phenomenological Goldreich & Sridhar theory of strong MHD turbulence and on weak MHD turbulence theory. We recover the predictions of the Lazarian & Vishniac theory for the reconnection rate of large-scale magnetic structures. Lazarian & Vishniac also invoked "spontaneous stochasticity," but of the field lines rather than of the Lagrangian trajectories. More recent theories of fast magnetic reconnection appeal to microscopic plasma processes that lead to additional terms in the generalized Ohm's law, such as the collisionless Hall term. We estimate quantitatively the effect of such processes on the inertial-range turbulence dynamics and find them to be negligible in most astrophysical environments. For example, the predictions of the Lazarian & Vishniac theory are unchanged in Hall MHD turbulence with an extended inertial range, whenever the ion skin depth δi is much smaller than the turbulent integral length or injection-scale Li. [ABSTRACT FROM AUTHOR]

There have been multiple claims that exposing water to a static magnetic field affects its properties which influence living systems. To test this hypothesis, planarian subsequent to dissection were maintained in spring water that had been previously exposed for only one day to one of three (16, 160, or 1,600 G) intensity static magnetic fields or to a reference condition. Although there was no significant difference in regeneration rates over the subsequent seven-day period, there was a statistically significant nonlinear effect for planarian mobility and diffusion rates. Both mobility rates and diffusion velocity of a liquid within the water that had been exposed to the 16 G field was about twice that for water exposed to the other intensities. These results imply that nonlinear biophysical effects may emerge under specific conditions of intensity ranges for particular volumes of water. [ABSTRACT FROM AUTHOR]

Abstract: Portable – or “laptop” – computers (LCs) are widely and increasingly used all over the world. Since LCs are often used in tight contact with the body even by pregnant women, fetal exposures to low frequency magnetic fields generated by these units can occur. LC emissions are usually characterized by complex waveforms and are often generated by the main AC power supply (when connected) and by the display power supply sub-system. In the present study, low frequency magnetic field emissions were measured for a set of five models of portable computers. For each of them, the magnetic flux density was characterized in terms not just of field amplitude, but also of the so called “weighted peak” (WP) index, introduced in the 2003 ICNIRP Statement on complex waveforms and confirmed in the 2010 ICNIRP Guidelines for low frequency fields. For the model of LC presenting the higher emission, a deeper analysis was also carried out, using numerical dosimetry techniques to calculate internal quantities (current density and in-situ electric field) with reference to a digital body model of a pregnant woman. Since internal quantities have complex waveforms too, the concept of WP index was extended to them, considering the ICNIRP basic restrictions defined in the 1998 Guidelines for the current density and in the 2010 Guidelines for the in-situ electric field. Induced quantities and WP indexes were computed using an appropriate original formulation of the well known Scalar Potential Finite Difference (SPFD) numerical method for electromagnetic dosimetry in quasi-static conditions. [Copyright &y& Elsevier]

Abstract: There is an ongoing scientific controversy whether the observed association between exposure to residential extremely low-frequency magnetic fields (ELF-MF) and the risk of childhood leukaemia observed in epidemiological studies is causal or due to methodological shortcomings of those studies. Recent pooled analysis confirm results from previous studies, namely an approximately two-fold risk increase at ELF-MF exposures ≥0.4 μT, and demonstrate consistency of studies across countries, with different design, different methods of exposure assessment, and different systems of power transmission and distribution. On the other hand, recent pooled analyses for childhood brain tumour show little evidence for an association with ELF-MF, also at exposures ≥0.4 μT. Overall, the assessment that ELF-MF are a possible carcinogen and may cause childhood leukaemia remains valid. Ongoing research activities, mainly experimental and few new epidemiological studies, hopefully provide additional insight to bring clarity to a research area that has remained inconclusive. [Copyright &y& Elsevier]

The article presents a study of the changes in the composition of lipids in the seeds of magnetically-oriented type (MOT) radish exposed in weak permanent magnetic field (PMF). It states that the contents of neutral and polar lipids change under the influence of weak PMF, while weak PMF under geomagnetic field changed lipid ratio. It suggests that the differences in the MOT response to changes are due to physiological inadequacy of the response and different sensitivity to weak PMF.

Some epidemiologic studies have suggested that extremely low frequency magnetic fields might affect human health and, in particular, that the incidence of certain types of cancer might increase among individuals living or working in environments exposed to such fields. This study is part of a broad study we conducted in humans. The study presented here was designed to look for possible effects of acute exposure to 50-Hz magnetic fields (10 μT) on the interleukin 1 beta (IL-1β), interleukin 2 (IL-2), interleukin 6 (IL-6), interleukin-1 receptor antagonist (IL-1RA), and the interleukin-2 receptor (IL-2R) production. Thirty-two young men (20-30 years old) were divided into two groups (sham-exposed or control group and exposed group) of 16 subjects each. All subjects participated in two 24-h experiments to evaluate the effects of both continuous and intermittent (1 h 'off' and 1 h 'on' with the field switched 'on' and 'off' every 15 s) exposure to linearly polarized magnetic fields. The subjects were exposed to the magnetic field from 2300 to 0800 while recumbent. Blood samples were collected during each session at 11:00, 17:00, 22:00, 01:00, 04:00, 06:00, and 08:00. Results showed that exposure to 50-Hz magnetic fields (10 μT) significantly increases IL-6 when subjects were exposed to an intermittent magnetic field. However, no effect has been observed on interleukin IL-1β, IL-2, IL-1RA, and IL-2R. [ABSTRACT FROM AUTHOR]

It has been suggested that residential exposure to contact currents may be more directly associated with the potential for an increased risk of leukemia in childhood than magnetic fields. Contact current exposure occurs when a child contacts a bathtub's water fixtures, which are usually contiguous with a residence's electrical ground, and when the drainpipe is conductive. The Northern California Childhood Leukemia Study (NCCLS) is the only epidemiological study known to address whether contact current may confound the reported association between residential magnetic fields and childhood leukemia. The study contributed contact voltage and magnetic-field data for over 500 residences of leukemia cases and control children. We combined these data with the results of previous measurement studies of contact voltage in other communities to conduct an analysis of the relationship of magnetic fields with contact voltage for a total sample of 702 residences. The Spearman correlation of magnetic field with contact voltage was 0.29 (Spearman, P < 0.0001). Magnetic-field and contact voltage data were both divided into tertiles, with an upper magnetic-field cutpoint of 0.3 μT suggested by values used in epidemiological results and an upper contact voltage cutpoint of 60 mV based on dosimetric considerations. Expressed as an exposure odds ratios (EOR), we report an association of contact voltage with magnetic fields of 15.1 (95%% CI 3.6-61) as well as a statistically significant positive trend across magnetic-field strata (EOR of 4.2 per stratum with 95%% CI 2.4-7.4). The associations appear to be large enough to support the possibility that contact current could be responsible for the association of childhood leukemia with magnetic fields. [ABSTRACT FROM AUTHOR]

The effects of magnetic fields (MF) with different intensity, which are applied in magnetotherapy, on the redox homeostasis in chloroplasts of two-week-old pea ( Pisum sativum L.) cvs. Albumen and Shustrik were studied. The seedlings were treated with weak MF produced by the generators UMTI-ZF or that from Electro-Biology firm for 15, 30, 60, and 120 min. Production of early and final products of lipid peroxidation (POL) (dienoic conjugates, MDA, and Schiff bases) and also activity of superoxide dismutase (SOD) and the content of ascorbic acid (Asc) in chloroplasts were assessed. The stronger pulse MF (PMF-1) induced a stable decrease of POL products, whereas the weaker PMF-2 induced reversible accumulation of dienoic conjugates and Schiff bases. PMF-1 successively activated SOD, inhibited it, and finally stabilized its activity at the control level. Similar treatment with PMF-2 induced similar SOD activity changes but did not inhibit SOD. The faster response of Asc to PMF-1 was noted. [ABSTRACT FROM AUTHOR]

In this work the retardation of Ehrlich tumor growth implanted in mice was studied by employing 4.5 Hz magnetic field. Eighty female Balb/c mice were used, twenty as normal group; the other sixty mice were inoculated with Ehrlich tumor, then they were divided equally into three groups namely A, B and C. Group A (control group) animals were not exposed to the magnetic field. The tumors in the thigh of the animals of group B were exposed to 4.5 Hz, 2 Gauss square wave magnetic field by using a small solenoid connected to a power square wave generator. Group C animals were whole body exposed inside a large solenoid to 4.5 Hz, 2 Gauss square wave magnetic field. Both groups B and C were exposed for a period of 2 weeks at a rate 2 hours per day. Tumor volume, survival period, histological examination and dielectric relaxation of the tumor were measured to investigate the activity of the tumor of the exposed and the unexposed animals. The results indicated that exposing the tumor tissue to 4.5 Hz square wave magnetic field for 2 weeks at a rate 2 hours/day inhibited tumor growth and increased the survival period of the animals. However, group B showed more improvements than did group C. This was attributed to some distortions in the square waveform in the large solenoid (group C). By comparing data from current and previous work, it was concluded that the use of magnetic waves showed better results over previously published work using amplitude modulated electromagnetic waves with the same frequency. [ABSTRACT FROM AUTHOR]

Abstract: This investigation aimed to study the effects of magnetic treatments (normal seeds irrigated with tap water, magnetized seeds irrigated with tap water, normal seeds irrigated with magnetized water and magnetized seeds irrigated with magnetized water) on growth, water relations, photosynthetic pigments, proline and water use efficiency as well as anatomical characters of tomato plants grown under three levels of water deficit (80%, 60% and 40% field capacities) beside the control 100% Field capacity. Pot experiments were conducted during 2009 and 2010 seasons under the natural conditions of the greenhouse of the Agriculture Faculty, Menufiya University, Shibin El-Kom, Egypt. Water deficit at 60 and 40% FC significantly decreased all growth, most physiological and anatomical characters. Tomato seeds irrigated with magnetized water and magnetized seeds irrigated with magnetized water treatments were the best treatments for overcoming the bad effects of water deficit on tomato plant growth characteristics, water relations, proline concentration and photosynthetic pigments, as well as anatomical structure of some organs of tomato plants. The positive effects were more pronounced at the levels of 60% and 40% field capacities. This study suggests that the effects of magnetic treatments act as a protective factors against water deficit. [Copyright &y& Elsevier]

Abstract: Magnetic iron oxide nanoparticles (MNPs) have been studied to circumvent the limitations of status-quo brain tumor therapy and can be targeted by applying an external magnetic field to lesions. To address the pharmacokinetic shortcomings of MNPs that can limit targeting efficiency, we recently reported a long-circulating polyethylene glycol modified, cross-linked starch MNP (PEG-MNP) suitable for magnetic targeting. Using a rat model, this work explores the biodistribution patterns of PEG-MNPs in organs of elimination (liver, spleen, lung, and kidney) and shows proof-of-concept that enhanced magnetic brain tumor targeting can be achieved due to the relatively long circulation lifetime of the nanoparticles. Reductions in liver (∼12-fold) and spleen (∼2.5-fold) PEG-MNP concentrations at 1h compared to parent starch-coated MNPs (D) confirm plasma pharmacokinetics observed previously. While liver concentrations of PEG-MNPs remained considerably lower than those observed for D at 1h through 60 h, spleen values continue to increase and are markedly higher at later time points – a trend also observed with histology. Limited to no distribution of PEG-MNPs was visualized in lung or kidney throughout the 60h course evaluated. Enhanced, selective magnetic brain tumor targeting (t = 1 h) of PEG-MNPs (12 mg Fe/kg) was confirmed in 9L-glioma tumors, with up to 1.0% injected dose/g tissue nanoparticle delivery achieved – a 15-fold improvement over targeted D (0.07% injected dose/g tissue). MRI and histological analyses visually confirmed enhanced targeting and also suggest a limited contribution of passive mechanisms to tissue retention of nanoparticles. Our results are exciting and justify both further development of PEG-MNP as a drug delivery platform and concurrent optimization of the magnetic brain tumor targeting strategy utilized. [Copyright &y& Elsevier]

Among a variety of hyperthermia methods, magnetic nanoparticle hyperthermia is a highly promising approach for its confined heating within the tumour. In this study we perform in  vivo animal experiments on implanted prostatic tumours in mice to measure temperature distribution in the tumour during magnetic nanoparticle hyperthermia. Temperature elevations are induced by a commercially available ferrofluid injected via a single injection to the centre of the tumour, when the tumour is subject to an alternating magnetic field. Temperature mapping in the tumours during magnetic nanoparticle hyperthermia has demonstrated the feasibility of elevating tumour temperatures higher than 50°°C using only 0.1 cm3 ferrofluid injected in the tumour under a relatively low magnetic field (3 kA/m). Detailed 3-D nanoparticle concentration distribution is quantified using a high-resolution microCT imaging system. The calculated nanoparticle distribution volume based on the microCT scans is useful to analyse nanoparticle deposition in the tumours. Slower ferrofluid infusion rates result in smaller nanoparticle distribution volumes in the tumours. Nanoparticles are more confined in the vicinity of the injection site with slower infusion rates, causing higher temperature elevations in the tumours. The increase in the nanoparticle distribution volume in the tumour group after the heating from that in the tumour group without heating suggests possible nanoparticle re-distribution in the tumours during the heating. [ABSTRACT FROM AUTHOR]

In the present work; the effect of whole body exposure of rats to mixed radiation (MR) from fast neutrons (FN) and 50Hz, 0.05mT magnetic field (MF) on the structural functions of the animal testis were investigated. For this; 100 white albino rats were divided equally into four groups namely A, B, C and D. Animals of group A were used as control, groups B and C were exposed to 50Hz, 0.05mT MF and fission neutrons from 252Cf source at a dose rate 10 μSv/h respectively for a period of 4 weeks at a rate of 8h/day and 5 days/week. Group D was exposed to fission neutrons and MF at the same field strengths and dose rates for the same period as groups B and C. At the end of the exposure period, blood was collected, animals were sacrificed and testes were removed for histopathological examination. The results indicated highly significant decrease (p<0.0001) of testosterone hormone level (THL) in blood for animals from all groups as compared to control. Moreover; highly significant increase (p<0.0001) in the creatine phosphokinase (CPK) enzyme in sera was measured for all exposed animals. Results were analyzed depending on the probable mechanisms of interaction of these types of radiation with biological tissue. It was concluded from the present findings that the induced damage of the testis and the dramatic elevated CPK enzyme levels are higher for exposure to mixed radiation as compared with exposure to a single field. [ABSTRACT FROM AUTHOR]

In this study, a static magnetic field influence on development and viability in two different species, Drosophila melanogaster and Drosophila hydei, was investigated. Both species completed development (egg--adult), in and out of the static magnetic field induced by double horseshoe magnet. Treated vials with eggs were placed in the gap between magnetic poles (47  mm) and exposed to the average magnetic induction of 60  mT, while control ones were kept far enough from magnetic field source. We found that exposure to the static magnetic field reduced development time in both species, but statistical significance was found only for D. hydei. Furthermore, we found that the average viability of both Drosophila species exposed to the magnetic field was significantly weaker compared to control ones. These results indicate that 60  mT static magnetic field could be considered as a potential stressor, influencing on different levels the embryonic and post-embryonic development of individuals. [ABSTRACT FROM AUTHOR]

We aimed to provide a systematic evaluation of magnetic field (MF) exposure of staff working in the offices located above or close to transformer stations (TS) and electric enclosures (EE). Occupational short-term ''spot'' measurements with Narda EFA-300 and isotropic magnetic field probe were carried out in two National Banks and one Industrial Company having more than 500 employees. Extremely low-frequency (ELF) MFs up to several tens of μμT were measured in the mentioned working environments. 25% of the measured MFs were found less than 0.3  μμT, the background exposure level that staff receive at home, 75% were above 0.3  μμT with the highest value of 6.8  μμT. The mean and median personal exposures were calculated to be 1.19  μμT and 0.56  μμT, respectively. Most of the staff (83%) is under risk based on epidemiological studies that reported a statistically significant association between risk of leukemia and averaged magnetic fields of 0.2  μμT or over. Results showed that risk evaluation should be considered to minimize the possibility of the workers being harmed due to exposure to work-related electromagnetic sources. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic fields (MFs) have been applied for the first time in orchid micropropagation. Protocorm-like bodies (PLBs) – approximately 3mm in diameter – first derived from leaf segment culture of Phalaenopsis Gallant Beau ‘George Vazquez’, were subcultured every 2 months, and served as initial explants. The proliferation of Phalaenopsis PLBs in liquid medium in the Miracle Pack® culture system was affected by the action of different intensities and polarities of MFs: 0.1, 0.15 and 0.2Tesla (T) at North (N) and South (S) poles. The MF of 0.1T – S resulted in the greatest fresh weight of regenerated PLBs. The average number of neo-PLBs formed per clusters in the PLB treated by MF: 0.1–0.2T was decreased compared to the control exposed to natural MF (5×10−6 T). The proliferation of PLBs under 0.15T – MF at both N and S poles for 2 and 7 weeks demonstrated that a longer duration of exposure to an MF of 0.15T, regardless of the polarity, resulted in greater biomass of newly formed PLBs and smaller average number of newly formed PLBs. The S pole of MF had stronger effects on Phalaenopsis PLBs proliferation than the N pole did in all treatments. [Copyright &y& Elsevier]

We present the design, fabrication, and characterization of a resonant magnetic field sensor based on Microelectromechanical systems (MEMS). This sensor exploits the Lorentz force principle and uses a Wheatstone bridge of p-type piezoresistors. Its resonant structure is integrated with silicon beams (15 μm wide and 5 μm thick) and an aluminum loop (9 μm wide and 1 μm thick). The sensor operates in its first flexural resonant frequency (22.99 kHz) and has a linear response, a high resolution (43 nT), a sensitivity of 1.94 V·T-1, a quality factor of 96.6 at atmospheric pressure, and power consumption close to 16 mW. [ABSTRACT FROM AUTHOR]