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We demonstrate the fabrication of nanoelectromagnets and the magnetic capture of a single magnetic nanoparticle. The magnetic nanoparticles are extracted from magnetotactic bacteria and their diameter is approximately 50 nm. We show that a single nanoparticle is captured at each corner of the serpentine-shaped nanoelectromagnet, and the maximum magnetic field of 35 mT (and the maximum magnetic-field gradient of 4×105 T/m) is shown to be created at the capture spots of the nanoelectromagnet. It is also shown that there is a crossover between the magnetic force and the diffusion force at several hundred nm away from the magnet. This distance is comparable to the average interparticle distance. [ABSTRACT FROM AUTHOR]

The article discusses the use of magnetism in medicine. Magnetism has been used in various diagnostic and therapeutic process in medicine and physiology. Some of the advanced research at the Wiezmann Institute and other institutions regarding the magnetic fields is discussed and evaluated including the electric potentials or magnetic phosphenes, muscle stimulation, and magnetic controls. The development of magnetic tools are also discussed including magnetic catheters, and the improvement of contrast materials for X-ray.

Abstract We assessed genotoxic effects of intermediate frequency magnetic fields (MF) in vitro and in vivo. Rat primary astrocytes were exposed for 24 h to a 7.5 kHz MF at a magnetic flux density of 30 or 300 µT. Male C57BL/6 J mice were exposed continuously for 5 weeks to a 7.5 kHz MF at 12 or 120 μT, and blood samples were collected for the genotoxicity assays. To evaluate possible co-genotoxicity, the in vitro experiments included combined exposure with menadione (an agent that induces mitochondrial superoxide production and DNA damage) and methyl methanesulfonate (an alkylating agent). DNA damage and DNA repair (in vitro) were measured using the alkaline Comet assay and formation of micronuclei was assessed microscopically (in vivo) or using flow cytometry (in vitro). The results did not support genotoxicity or co-genotoxicity of 7.5 kHz MFs at magnetic flux densities up to 300 µT in vitro or in vivo. On the contrary, there was some evidence that exposure to 7.5 kHz MFs might reduce the level of genetic damage. Strongest indication of any biological effects was obtained from measurements of relative cell number, which was significantly and consistently increased after MF exposure in all in vitro experiments. Health implications of this finding are unclear, but it suggests that 7.5 kHz MFs may stimulate cell proliferation or suppress cell death. Highlights • Human exposure to intermediate frequency magnetic fields is increasing. • 7.5 kHz magnetic fields were not genotoxic in animals or in vitro. • Magnetic field exposure did not enhance effects of genotoxic chemicals. • There was some evidence of protection against genotoxicity. • The number of cells was increased in the exposed cultures. [ABSTRACT FROM AUTHOR]

Human exposure to intermediate frequency (IF) fields is increasing due to new applications such as electronic article surveillance systems, wireless power transfer and induction heating cookers. However, limited data is available on effects of IF magnetic fields (MF) on male fertility function. This study was conducted to assess possible effects on fertility indicators from exposure to IF MF. Male C57BL/6J mice were exposed continuously for 5 weeks to 7.5 kHz MF at 12 and 120 μT. Sperm cells from cauda epididymis were analysed for motility, total sperm counts, and head abnormalities. Motile sperm cells were classified as progressive or non-progressive. Testicular spermatid heads were counted as well. The body weight development and reproductive tissue weights were not affected. No exposure-related differences were observed in sperm counts or sperm head abnormalities. Proportion of non-motile cells was significantly decreased in the 120 µT group, and a corresponding increase was seen in the percentage of motile cells (significant in non-progressive motile cells). In conclusion, no adverse effects on fertility indicators were observed. Increased sperm motility is an interesting finding that needs to be confirmed in further studies. [ABSTRACT FROM AUTHOR]

Artificial, anisotropic fibre phantoms are nowadays increasingly used in the field of diffusion-weighted MRI. Such phantoms represent useful tools for, among others, the calibration of pulse sequences and validation of diffusion models since they can mimic well-known structural features of brain tissue on the one hand, but exhibit a reduced complexity, on the other. Among all materials, polyethylene fibres have been widely used due to their excellent properties regarding the restriction of water diffusion and surface relaxation properties. Yet the magnetic susceptibility of polyethylene can be distinctly lower than that of distilled water. This difference produces strong microscopic, background field gradients in the vicinity of fibre bundles which are not parallel to the static magnetic field. This, in turn, modulates the MRI signal behaviour. In the present work we investigate an approach to reduce the susceptibility-induced background gradients via reducing the heterogeneity in the internal magnetic susceptibility. An aqueous solution of magnesium chloride hexahydrate (MgCl2·6H2O) is used for this purpose. Its performance is demonstrated in dedicated anisotropic fibre phantoms with different geometrical configurations. [ABSTRACT FROM AUTHOR]

Some effects of low-intensity magnetic fields on the concentration of radicals and their influence on cellular functions are reviewed. These fields have been implicated as a potential modulator of radical recombination rates. Experimental evidence has revealed a tight coupling between cellular function and radical pair chemistry from signaling pathways to damaging oxidative processes. The effects of externally applied magnetic fields on biological systems have been extensively studied, and the observed effects lack sufficient mechanistic understanding. Radical pair chemistry offers a reasonable explanation for some of the molecular effects of low-intensity magnetic fields, and changes in radical concentrations have been observed to modulate specific cellular functions. Applied external magnetic fields have been shown to induce observable cellular changes such as both inhibiting and accelerating cell growth. These and other mechanisms, such as cell membrane potential modulation, are of great interest in cancer research due to the variations between healthy and deleterious cells. Radical concentrations demonstrate similar variations and are indicative of a possible causal relationship. Radicals, therefore, present a possible mechanism for the modulation of cellular functions such as growth or regression by means of applied external magnetic fields. [ABSTRACT FROM AUTHOR]

The Escherichia coli(E. coli) isGram negative bacteria, that normally live in the digestive tracts of humans and animals, can cause bloody diarrhea, severe anemia or kidney falureand other illnesses which can lead to death.Systemic therapy with antibiotic cause bacteria resistant. So, an alternative method is needed, one of them is Photodynamic therapy (PDT).This research aims to investigate antimicrobial photodynamic effects of the light emitting diode (LED) activated bymagnetic fields 1.8 mT irradiation to bacteria viability . To determine the antimicrobial effect of treatments, three measurements of bacterial colony growth (in %) were carried out. Three measurements groups as follow: Groups I to measurements the effects of LED irradiation by varying wavelength (469nm, 541 nm and 626 nm); Groups II to measurements effects of magnetic fields 1.8 mT to antimicrobial efficacy; Groups III to determine the effects and efficacy of LED 541 nm and magnetic fields irradiation with varying LED intensity (0.62, 2.50, 6.27, and 8.21) mW/cm2 and time irradiation (20, 30, 40, 50) minutes, respectively. The suspension was planted on sterile media and incubated at a temperature of 37°C for 24 hours. After incubation, the number of colony-forming units per milliliter (CFU/ml) was determined. The results were analyzed by analysis of variance (ANOVA) and the Tukey test. A P value ⩽0.05 was considered to indicate a statistically significant difference. The LED treatment group 469 nm, 541 nm and 626 nm resulted in statistically significant decrease of CFU (p<0.05) compared to each other. The LED 541 nm treatment group with magnetic fields resulted significantly differ with treatment group without magnetic fields. The LED 541 nm treatment with magnetic fields 1.8 mT at various light intensity and time irradiation resulted significantly differ each other (p<0.05). LED irradiation with intensity 6.27 mW/cm2 and time irradiation 50 minutes (energy dose 18.81 J/cm2) resulted highest decreases the number of bacteria E.coli 80%. LED irradiation combined by magnetic fields can improve the efficacy of antimicrobial photodynamic effects. [ABSTRACT FROM AUTHOR]

The aim was to investigate occupational exposure to electric and magnetic fields during tasks at ground or floor level at 110kV substations in Finland and to compare the measured values to Directive 2013/35/EU. Altogether, 347 electric field measurements and 100 magnetic field measurements were performed. The average value of all electric fields was 2.3 kV/m (maximum 6.4kV/m) and that of magnetic fields was 5.8 µT (maximum 51.0 µT). It can be concluded that the electric and magnetic field exposure at ground or floor level is typically below the low action levels of Directive 2013/35/EU. The transposition of the directive will not create new needs to modify the work practice of the evaluated tasks, which can continue to be performed as before. However, for workers with medical implants, the exposure may be high enough to cause interference. [ABSTRACT FROM AUTHOR]

In electric vehicles, passengers sit very close to an electric system of significant power. The high currents achieved in these vehicles mean that the passengers could be exposed to significant magnetic fields (MFs). One of the electric devices present in the power train are the batteries. In this paper, a methodology to evaluate the MF created by these batteries is presented. First, the MF generated by a single battery is analyzed using finite-elements simulations. Results are compared with laboratory measurements, which are taken from a real battery, to validate the model. After this, the MF created by a complete battery pack is estimated, and results are discussed. [ABSTRACT FROM PUBLISHER]

The possible neurological and biophysical effects of magnetic fields on animals is an area of active study. Here, we report that courtship activity of male Drosophila increases in a magnetic field and that this effect is regulated by the blue light-dependent photoreceptor cryptochrome (CRY). Naïve male flies exhibited significantly increased courtship activities when they were exposed to a ≥ 20-Gauss static magnetic field, compared with their behavior in the natural environment (0 Gauss). CRY-deficient flies, cryb and crym, did not show an increased courtship index in a magnetic field. RNAi-mediated knockdown of cry in cry-GAL4-positive neurons disrupted the increased male courtship activity in a magnetic field. Genetically expressing cry under the control of cry-GAL4 in the CRY-deficient flies restored the increase in male courtship index that occurred in a magnetic field. Interestingly, artificially activating cry-GAL4-expressing neurons, which include large ventral lateral neurons and small ventral lateral neurons, via expression of thermosensitive cation channel dTrpA1, also increased the male courtship index. This enhancement was abolished by the addition of the cry-GAL80 transgene. Our results highlight the phenomenon of increased male courtship activity caused by a magnetic field through CRY-dependent magnetic sensation in CRY expression neurons in Drosophila. [ABSTRACT FROM AUTHOR]

Objectives: Recent studies have consistently shown that amongst staff working with MRI, transient symptoms directly attributable to the MRI system including dizziness, nausea, tinnitus, and concentration problems are reported. This study assessed symptom prevalence and incidence in radiographers and other staff working with MRI in healthcare in the UK. Methods: One hundred and four volunteer staff from eight sites completed a questionnaire and kept a diary to obtain information on subjective symptoms and work practices, and wore a magnetic field dosimeter during one to three randomly selected working days. Incidence of MRI-related symptoms was obtained for all shifts and prevalence of MRI-related and reference symptoms was associated to explanatory factors using ordinal regression. Results: Incident symptoms related to working with MRI were reported in 4 % of shifts. Prevalence of MRI-related, but not reference symptoms were associated with number of hours per week working with MRI, shift length, and stress, but not with magnetic field strength (1.5 and 3 T) or measured magnetic field exposure. Conclusions: Reporting of prevalent symptoms was associated with longer duration of working in MRI departments, but not with measured field strength of exposure. Other factors related to organisation and stress seem to contribute to increased reporting of MRI-related symptoms. Key Points: • Routine work with MRI is associated with increased reporting of transient symptoms • No link to the strength of the magnetic field was demonstrated. • Organisational factors and stress additionally contribute to reporting of MRI-related symptoms [ABSTRACT FROM AUTHOR]

Amyotrophic lateral sclerosis (ALS) has been associated with exposures in so-called 'electrical occupations'. It is unclear if this possible link may be explained by exposure to extremely low-frequency magnetic fields (ELF-MF) or by electrical shocks. We evaluated ALS mortality in 2000-2008 and exposure to ELF-MF and electrical shocks in the Swiss National Cohort, using job exposure matrices for occupations at censuses 1990 and 2000. We compared 2.2 million workers with high or medium vs. low exposure to ELF-MF and electrical shocks using Cox proportional hazard models. Results showed that mortality from ALS was higher in people who had medium or high ELF-MF exposure in both censuses (HR 1.55 (95% CI 1.11-2.15)), but closer to unity for electrical shocks (HR 1.17 (95% CI 0.83-1.65)). When both exposures were included in the same model, the HR for ELF-MF changed little (HR 1.56), but the HR for electric shocks was attenuated to 0.97. In conclusion, there was an association between exposure to ELF-MF and mortality from ALS among workers with a higher likelihood of long-term exposure. [ABSTRACT FROM AUTHOR]

Purpose: Data from the Northern California Childhood Leukemia Study (NCCLS) were used to assess whether selection bias may explain the association between residential magnetic fields (assessed by wire codes) and childhood leukemia as previously observed in case-control studies. Methods: Wiring codes were calculated for participating cases, n = 310; and non-participating cases, n = 66; as well as for three control groups: first-choice participating, n = 174; first-choice non-participating, n = 252; and replacement (non-first choice participating controls), n = 220. Results: Participating controls tended to be of higher socioeconomic status than non-participating controls, and lower socioeconomic status was related to higher wire-codes. The odds ratio (OR) for developing childhood leukemia associated with high wire-codes was 1.18 (95% CI: 0.85, 1.64) when all cases were compared to all first-choice controls (participating and non-participating). The OR for developing childhood leukemia in the high current category was 1.43 (95% CI: 0.91, 2.26) when participating cases were compared to first-choice participating controls, but no associations were observed when participating cases were compared to non-participating controls (OR = 1.06, 95% CI: 0.71, 1.57) or to replacement controls (OR = 1.06, 95% CI: 0.71, 1.60). Conclusions: The observed risk estimates vary by type of control group, and no statistically significant association between wire codes and childhood leukemia is observed in the California population participating in the NCCLS. [ABSTRACT FROM AUTHOR]

Abstract: Over the last two decades residential exposure to extremely low frequency magnetic fields (ELF MF) has been associated with childhood leukaemia relatively consistently in epidemiological studies, though causality is still under investigation. We aimed to estimate the cases of childhood leukaemia that might be attributable to exposure to ELF MF in the European Union (EU27), if the associations seen in epidemiological studies were causal. We estimated distributions of ELF MF exposure using studies identified in the existing literature. Individual distributions of exposure were integrated using a probabilistic mixture distribution approach. Exposure–response functions were estimated from the most recently published pooled analysis of epidemiological data. Probabilistic simulation was used to estimate population attributable fractions (AFP) and attributable cases of childhood leukaemia in the EU27. By assigning the literature review-based exposure distribution to all EU27 countries, we estimated the total annual number of cases of leukaemia attributable to ELF MF at between ~50 (95% CIs: −14, 132) and ~60 (95% CIs: −9, 610), depending on whether exposure–response was modelled categorically or continuously, respectively, for a non-threshold effect. This corresponds to between ~1.5% and ~2.0% of all incident cases of childhood leukaemia occurring annually in the EU27. Considerable uncertainties are due to scarce data on exposure and the choice of exposure–response model, demonstrating the importance of further research into better understanding mechanisms of the potential association between ELF MF exposure and childhood leukaemia and the need for improved monitoring of residential exposures to ELF MF in Europe. [Copyright &y& Elsevier]

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]

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: 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]

The article focuses on a study that assessed the magnetic field exposure level of welders during welding. The experiment was conducted with the help of Hall magnetometer for obtaining the data and analyzing the result and also informs that finite element method was used to analyze the human hand tissue for the electromagnetic field dosimetry. The result shows that calculated eddy current was much lower than the well-known muscular stimulation.

Purpose: The aim of this study was to examine the effect of extremely low-frequency magnetic fields (MF) and the endocrine-disrupting compound atrazine, each separately, on the thyroid gland of juvenile-peripubertal rats, and to investigate the possible synergistic effect of these two factors combined. Materials and methods: The study was performed on male Wistar rats from postnatal day 23-53. Animals were divided into six groups: (1) 4 h/day exposure to MF (50 Hz, 100-300 μT, 54-160 V/m), (2) 20 mg/kg of body weight (bw) of atrazine, (3) 200 mg/kg bw of atrazine, (4) MF with 20 mg/kg bw of atrazine (5) MF with 200 mg/kg bw of atrazine, and (6) control. Results: Light and electron microscopic studies demonstrated no significant alterations in the thyroid structure between the treated groups and the control. Significant outcomes were found regarding the volume density of thyroid follicles and the connective tissue between the MF-exposed group when compared to both atrazine treatments and the combined treatments. The high dose of atrazine significantly affected the number of mast cells compared to the control. Conclusions: No synergistic effect of the MF and the endocrine-disrupting compound atrazine on the thyroid gland has been found. The specific histological alterations of the thyroid parenchyma observed in some treated groups require further investigation. [ABSTRACT FROM AUTHOR]

This paper investigates design, modeling, simulation, and control issues related to self-propelled endoscopic capsule navigated inside the human body through external magnetic fields. A novel magnetic propulsion system is proposed and fabricated, which has great potential of being used in the field of noninvasive gastrointestinal endoscopy. Magnetic-analysis model is established and finite-element simulations as well as orthogonal design are performed for obtaining optimized mechanical and control parameters for generating appropriate external magnetic field. Simulated intestinal tract experiments are conducted, demonstrating controllable movement of the capsule under the developed magnetic propulsion system. [ABSTRACT FROM AUTHOR]

Background: Previous pooled analyses have reported an association between magnetic fields and childhood leukaemia. We present a pooled analysis based on primary data from studies on residential magnetic fields and childhood leukaemia published after 2000.Methods: Seven studies with a total of 10,865 cases and 12,853 controls were included. The main analysis focused on 24-h magnetic field measurements or calculated fields in residences.Results: In the combined results, risk increased with increase in exposure, but the estimates were imprecise. The odds ratios for exposure categories of 0.1-0.2 μT, 0.2-0.3 μT and ≥0.3 μT, compared with <0.1 μT, were 1.07 (95% CI 0.81-1.41), 1.16 (0.69-1.93) and 1.44 (0.88-2.36), respectively. Without the most influential study from Brazil, the odds ratios increased somewhat. An increasing trend was also suggested by a nonparametric analysis conducted using a generalised additive model.Conclusions: Our results are in line with previous pooled analyses showing an association between magnetic fields and childhood leukaemia. Overall, the association is weaker in the most recently conducted studies, but these studies are small and lack methodological improvements needed to resolve the apparent association. We conclude that recent studies on magnetic fields and childhood leukaemia do not alter the previous assessment that magnetic fields are possibly carcinogenic. [ABSTRACT FROM AUTHOR]

Background: Epidemiological evidence suggests that chronic low-intensity extremely-low-frequency magnetic-field exposure is associated with increased risk of childhood leukaemia; it is not certain the association is causal.Methods: We report a national case-control study relating childhood cancer risk to the average magnetic field from high-voltage overhead power lines at the child's home address at birth during the year of birth, estimated using National Grid records. From the National Registry of Childhood Tumours, we obtained records of 28,968 children born in England and Wales during 1962-1995 and diagnosed in Britain under age 15. We selected controls from birth registers, matching individually by sex, period of birth, and birth registration district. No participation by cases or controls was required.Results: The estimated relative risk for each 0.2 μT increase in magnetic field was 1.14 (95% confidence interval 0.57 to 2.32) for leukaemia, 0.80 (0.43-1.51) for CNS/brain tumours, and 1.34 (0.84-2.15) for other cancers.Conclusion: Although not statistically significant, the estimate for childhood leukaemia resembles results of comparable studies. Assuming causality, the estimated attributable risk is below one case per year. Magnetic-field exposure during the year of birth is unlikely to be the whole cause of the association with distance from overhead power lines that we previously reported. [ABSTRACT FROM AUTHOR]

Normal young adults were exposed for 20min once per week for a total of 3 sessions to 1 of 7 configurations of weak (1 microTesla) magnetic fields or to a sham field. The fields were spatially rotated and applied through the brain at the level of the temporoparietal lobes. The Profile of Mood States was taken before and after each session. Before, during, and after the treatments, heart rate, plethysmographic activity, and skin conductance were measured by computer. The results indicated that the burst-firing pattern previously demonstrated to be effective for clinical depression, improved mood and vigour compared to the sham-field or other treatments. Subjects who were exposed to a burst-firing pattern, a complex-sequenced pattern, and a pattern whose electrical equivalents stimulate long-term potential in hippocampus slices also exhibited less psychometric fatigue after the sessions compared to subjects who received the sham field or random-sequenced fields. These results replicate previous studies and indicate that rationally designed complex patterns of magnetic fields may simulate pharmacological treatments. [ABSTRACT FROM AUTHOR]

Abstract: Nesting on high voltage transmission line towers exposes birds to electric and magnetic fields for long periods. Nestlings are exposed from their development in ovo until fledging. This is a critical period for them because the quality of the developmental environment may affect their fitness at adulthood. We carried out a field study on Eurasian kestrels, Falco tinnunculus, to compare chicks from pairs nesting on high voltage power lines vs. those nesting in control sites in similar habitats. The magnetic field (MF) was measured in each nest-box and analysed in relation to growth curves, melatonin levels, leukocyte counts, and fledging success. None of the variables differed between exposed and control nestlings. Wing length (proxy of age) showed a negative covariation with serum melatonin concentration. Our findings suggest that exposure to MFs produced by high voltage power lines during the embryonic and post-hatching period (until fledging) does not have significant short-term physiological effects on kestrel nestlings. [Copyright &y& Elsevier]

Sterilization effects of the pulsed magnetic field with a maximum intensity of 11.37 Tesla were investigated on Escherichia coli AS 1.129, Staphylococcus aureus AS 1.89, Saccharomyces cerevisiae ATTC 7552 and Bacillus subtilis AS 1.921. The well-regulated fluctuations of sterilization effects with magnetic field intensity and pulse number were observed, and can be described by the ¿window effect¿ of magnetic fields and provide a better explanation of the inconsistent results of PMF sterilization in published literature. Sensibility of bacteria on the pulsed magnetic field significantly depends on a variety of microorganisms. Sterilization effects of a flowing sample were better than that of static samples. [ABSTRACT FROM AUTHOR]

Drug resistance is an obstacle for chemotherapy success. Because of this, this work aims to improve the cell killing effect of antineoplastic drugs by magnetic field (MF) co-exposure. S. cerevisiae cells were exposed to 2.45 mT, sinusoidal 50 Hz MF, during 48 h, and the drugs cisplatin (cisPt), mitomycin C (MMC), or methotrexate (MTX); 100 and 1,000 μg/ml. Survival was assayed by the drop test. The results showed that MF exposures do not induce alterations in the potency of cisPt, MMC, and MTX on these cells in relation to untreated controls. In addition, a strong correlation between temperature and potency of cisPt was found, which contribute to the establishment of the importance of an exhaustive control of temperature in experiments carried out with temperature sensitive antineoplastic agents in co-exposure with MF; avoiding differences between MF-exposed samples and unexposed controls and contributing to the performance of experiments under well-defined and controlled conditions. [ABSTRACT FROM AUTHOR]

There is increasing interest in using permanent magnets for therapeutic purposes encouraged by basic science publications and clinical reports. Magnetotherapy provides a non invasive, safe, and easy method to directly treat the site of injury, the source of pain and inflammation, and other types of disease. The physiological bases for the use of magnetic fields for tissue repair as well as physical principles of dosimetry and application of various magnetic fields are subjects of this review. Analysis of the magnetic and electromagnetic stimulation is followed by a discussion of the advantage of magnetic field stimulation compared with electric current and electric field stimulation. [ABSTRACT FROM AUTHOR]

The article discusses the result of the study concerning the possible biological effects of electric and magnetic fields and the duration of public and occupational exposure to be allowed. The International Commission on Non-Ionizing Radiation Protection expanded their guidelines by taking into account the harmonic components of the magnetic field with phase angles. The study aims to investigate magnetic fields, especially the harmonic components, in electric distribution substations from the public and occupation exposure point of view.

The effect of a magnetic field and surfactants on the rheological properties of strontium ferrite suspensions has been studied. An applied magnetic field is shown to raise the suspension viscosity, which is attributable to the formation of three-dimensional chain structures made up of ferrite particles. After the magnetic field is removed, these structures do not fully break down, which leads to hysteretic behavior of the suspension viscosity. The introduction of polyelectrolytes reduces the viscosity of the suspension both in a magnetic field and after the field is removed. This is due to the formation of an electrical double layer on the particle surface, which reduces interparticle friction and the strength of the three-dimensional structures. The results of this study may be useful in devising processes for enhancing the texture and density of highly anisotropic strontium ferrite materials produced by wet pressing. [ABSTRACT FROM AUTHOR]

The effect of finite electron mass on the formation and sustainment of a field reversed configuration (FRC) by rotating magnetic fields (RMF) is studied. The importance of inertial effects is measured by the ratio between the RMF frequency (ω) and the electron-ion collision frequency (ν). In the limit where this ratio is very small (ω/ν→0), previous results corresponding to massless electrons are recovered. When ω/ν increases there are significant changes in the value of the minimum external rotating field needed to sustain the FRC and the time required to reach a steady state. Since ν decreases with increasing temperature and decreasing density, these effects are expected to become more important as fusion relevant temperatures are approached. [ABSTRACT FROM AUTHOR]

Exposure limits for magnetic fields in the extremely low frequency range (3 to 3000 hertz) have been established by a number of organizations. The limits are generally intended to prevent overstimulation of electrically sensitive tissue and are expressed as ceiling values—levels not to be exceeded even momentarily. Exposures near or above the limits occur around high-current equipment and often have large spatial and temporal variability. The combination of variable exposures and ceiling-value exposure limits means that a practical exposure assessment must be statistically based. Practical guidance for assessing compliance for these exposures is limited. To fill this gap, this work develops a statistically based sampling and analysis methodology for evaluating compliance with magnetic-field exposure guidelines, using 60-hertz exposures in the electric utility industry as a model. The resulting methodology relies on (1) defining a scenario that includes tasks with similar high-field exposures for a group of workers, (2) having appropriate protocols for performing magnetic-field personal exposure measurements or having an exposure data set corresponding to that scenario, (3) assuming that the measured peak field is consistent with the exposure limit, (4) assuming that the peak exposure values follow a lognormal distribution, and (5) collecting sufficient measurements to determine the probability of compliance with a desired degree of statistical confidence. As examples, specific compliance probabilities and their confidence intervals are estimated for electric utility scenarios from available personal exposure measurements. This specific application demonstrates the general methodology and indicates that compliance with existing exposure limits may become an issue for certain tasks. [ABSTRACT FROM AUTHOR]

For a circular magnetic nanodot in a vortex ground state, we study how the critical velocity vc of the vortex core reversal depends on the magnitude H of a bias magnetic field applied perpendicularly to the dot plane. We find that, similarly to the case H=0, the critical velocity does not depend on the size of the dot. The critical velocity is dramatically reduced when the negative (i.e., opposite to the vortex core direction) bias field approaches the value, at which a static core reversal takes place. A simple analytical model shows good agreement with our numerical result. [ABSTRACT FROM AUTHOR]

The article discusses the metabolic cage for exposing a single mouse to high magnetic fields for research in biomagnetic studies and information on the nitrogenous end products of a cockroach. It states that due to various reasons such as space in between the poles of magnet, use of only nonmagnetic material for construction and food and water supply for the animal puts certain limitations and restrictions on the design and construction of such cages. It also repots that the excreta of Blaberus craniifer Burmeister detected for of purines, pyrimidines, and allantoin. The experimental results places the cockroach B. craniifer with those insects which are wholly or chiefly adapted to uricotely as their mode of nitrogen excretion.

The article discusses the electromagnetic interactions between all electrically charged particles. Relativistic quantum electrodynamics (QED) has been stated as the theory that describes the electromagnetic interactions between all electrically charged particles and is the most precisely tested theory in physics. It has been shown in some theory and experiment that only 4 parts per trillion of uncertainty are found in studies of the magnetic moment of the electron. However, a new measurement developed, shows a more precise experiment result, depicting a factor close to 6. In response, a parallel theoretical effort have extended the QED calculations of the magnetic moment and has reached 10 times precision as high as the other method.