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The article discusses the field of magnetobiology, which studies the non-thermal effects of magnetic fields on biological systems. The literature in this field is often plagued by conflicting claims and methodological shortcomings, leading to an unbalanced body of research. The article highlights the potential of the radical pair mechanism (RPM) in understanding the effects of magnetic interactions in living systems. It specifically focuses on the RPM's role in the magnetic compass sense of migratory songbirds and its potential applications in other areas of magnetobiology. The article also mentions the importance of realistic models and experimental optimization in studying radical pair reactions. [Extracted from the article]

The article discusses the field of spin chemistry, which focuses on the effects of electron and nuclear spins in chemical reactions and properties of molecules related to magnetic fields. The development of spin chemistry requires collaboration between research communities in physics, chemistry, biology, materials science, and information science. The article introduces a special topic on spin chemistry, which includes 11 papers discussing recent developments in the field. Topics covered include magnetic field effects in living cells, the use of covalent organic frameworks as spin-dependent catalysts, and the potential applications of spin chemistry in areas such as medical diagnostics and crop yields. The article aims to inspire further progress in spin chemistry research and encourage more scientists to contribute to the field. [Extracted from the article]

We report on specific heat and magnetocaloric effect (MCE) measurements in single crystals of HoAl2, DyAl2, and TbAl2 measured by a heat flux technique using Peltier devices. Those compounds order ferromagnetically at 31 K, 61 K, and 106K respectively, and present a spin reorientation transition (SRT) below TC. We study the dependence of the SRT with magnetic field and temperature by means of specific heat measurements performed in single crystals oriented at the [100], [110], and [111] directions with the aid of calculations using a simple model. We obtained the conventional MCE for HoAl2 and TbAl2 and also the anisotropic version of the effect obtained indirectly from the specific heat for TbAl2 and DyAl2. We also present the results for a direct determination of the anisotropic MCE for DyAl2 by measuring the heat flux generated by a rotation of the single crystal under constant field. [ABSTRACT FROM AUTHOR]

The presence of impurity sites in the neighboring area of quantum dot systems has been inferred in various experiments. The impurity sites can be strongly coupled to the dots inducing additional transport channels and lifting the current blockade. Here, we study the current through a quantum dot coupled to an impurity site via spin-orbit interaction. We show how the current in a magnetic field can reveal the dot-impurity interaction and find regimes where the spin-orbit interaction increases the current by a few orders of magnitude. [ABSTRACT FROM AUTHOR]

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]

Highlights • Low-frequency magnetic field influenced on myofibrillar protein gel properties. • 0.5 mT was the optimum intensity for water-holding capacity of gel. • Low-frequency magnetic field affected secondary structures of myofibrillar protein. Abstract This study aimed to investigate the effect of a low-frequency magnetic field (LF-MF; 0, 0.25, 0.5, and 1.4 mT) on the gel properties of pork myofibrillar protein (MP) and to explore potential mechanisms. The water-holding capacity (WHC) and rheological properties of MP gels treated at 0.5 mT were better than those from other treatments. The water mobility did not change significantly as intensity increased, while the ratios of immobilized water (PT 21) and free water (PT 22) significantly decreased and increased, respectively. This suggested that the effect of LF-MF on MP hydration might be related to the formation of water clusters. Raman spectra suggested that α-helices unfolded and β-sheets, β-turns, and random coils were formed in MP gels (from 0.25 to 1.4 mT). Furthermore, the intensities of characteristic peaks in the tryptophan and aliphatic residues band were highest at 0.5 mT, indicating that 0.5 mT was the optimum intensity for hydrophobic interactions. [ABSTRACT FROM AUTHOR]

Aim: To investigate whether static magnetic fields (SMFs) have a positive effect on the migration and dentinogenesis of dental pulp stem cells (DPSCs) to promote reparative dentine formation. Methodology: In vitro scratch assays and a traumatic pulp exposure model were performed to evaluate the effect of 0.4‐Tesla (T) SMF on DPSC migration. The cytoskeletons of the DPSCs were identified by fluorescence immunostaining and compared with those of a sham‐exposed group. Dentinogenic evaluation was performed by analysing the expressions of DMP‐1 and DSPP marker genes using a quantitative real‐time polymerase chain reaction (qRT‐PCR) process. Furthermore, the formation of calcified deposits was examined by staining the dentinogenic DPSCs with Alizarin Red S dye. Finally, the role played by the p38 MAPK signalling pathway in the migration and dentinogenesis of DPSCs under 0.4‐T SMF was investigated by incorporating p38 inhibitor (SB203580) into the in vitro DPSC experiments. The Student's t‐test and the Kruskal–Wallis test followed by Dunn's post hoc test with a significance level of P < 0.05 were used for statistical analysis. Results: The scratch assay results revealed that the application of 0.4‐T SMF enhanced DPSCs migration towards the scratch wound (P < 0.05). The cytoskeletons of the SMF‐treated DPSCs were found to be aligned perpendicular to the scratch wound. After 20 days of culture, the SMF‐treated group had a greater number of out‐grown cells than the sham‐exposed group (nonmagnetized control). For the SMF‐treated group, the DMP‐1 (P < 0.05) and DSPP genes (P < 0.05), analysed by qRT‐PCR, exhibited a higher expression. The distribution of calcified nodules was also found to be denser in the SMF‐treated group when stained with Alizarin Red S dye (P < 0.05). Given the incorporation of p38 inhibitor SB203580 into the DPSCs, cell migration and dentinogenesis were suppressed. No difference was found between the SMF‐treated and sham‐exposed cells (P > 0.05). Conclusion: 0.4‐T SMF enhanced DPSC migration and dentinogenesis through the activation of the p38 MAPK‐related pathway. [ABSTRACT FROM AUTHOR]

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]

Moderate intensity low frequency rotating magnetic field (LF-RMF) has been shown to inhibit melanoma, liver and lung cancer growth in mice. However, its effects on other types of cancers have not been investigated in vivo. Here, we show that 0-0.15T moderate intensity 4.2 Hz LF-RMF can inhibit tumor growth in mice bearing MDA-MB231 and MCF7 human breast cancer cells by over 30%. In contrast, the human gastrointestinal stromal tumor GIST-T1 growth was not inhibited by LF-RMF. In all RMF treatments, there were no apparent adverse effects on mice organs, body weight or water/food consumptions. However, the alanine aminotransferase (ALT) level was decreased in LF-RMF-treated mice bearing MCF7 and GIST-T1 cells, which indicated alleviated liver damage. Therefore, our study shows that moderate intensity LF-RMF might be a safe physical method that has clinical potentials to be used to inhibit breast cancer growth in the future. [ABSTRACT FROM AUTHOR]

Objectives Rotation of a static magnet over the motor cortex (MC) generates a transcranial alternating magnetic field (tAMF), and a linked alternating electrical field. The aim of this transcranial magnetic stimulation (TMS) study is to investigate whether such fields are able to influence MC excitability, and whether there are parallels to tACS induced effects. Methods Fourteen healthy volunteers received 20 Hz tAMF stimulation over the MC, over the vertex, and 20 Hz tACS over the MC, each with a duration of 15 min. TMS assessments were performed before and after the interventions. Changes in motor evoked potentials (MEP), short interval intra-cortical inhibition (SICI) and intra-cortical facilitation (ICF) were evaluated. Results The tACS and the tAMF stimulation over the MC affected cortical excitability in a different way. After tAMF stimulation MEP amplitudes and ICF decreased and the effect of SICI increased. After tACS MEP amplitudes increased and there were no effects on SICI and ICF. Conclusions The recorded single and paired pulse MEPs indicate a general decrease of MC excitability following 15 min of tAMF stimulation. Significance The effects demonstrate that devices based on rotating magnets are potentially suited to become a novel brain stimulation tool in clinical neurophysiology. [ABSTRACT FROM AUTHOR]

Purpose Previous studies have examined risks of leukaemia and selected lymphoid malignancies in workers exposed to extremely low frequency magnetic fields (ELF-MF). Most studies evaluated hematolymphopoietic malignancies as a combined category, but some analyses suggested that effects may be contained to some specific leukaemia or lymphoma subtypes, with inconsistent results. Methods We examined exposure to ELF-MF and mortality 1990–2008 from different types of hematolymphopoietic cancers in the Swiss National Cohort, using a job exposure matrix for occupations recorded at censuses 1990 and 2000. We analysed 3.1 million workers exposed at different levels to ELF-MF: ever-high, only-medium, only-low exposure using Cox proportional hazard models. We evaluated risk of death from acute myeloid leukaemia (AML), chronic myeloid leukaemia, lymphoid leukaemia, diffuse large B-cell lymphomas, follicular lymphoma, Waldenström's macroglobulinemia, multiple myeloma and Hodgkin lymphoma. Results Mortality from hematolymphopoietic cancers was not associated with exposure to ELF-MF with the exception of an increase in ever-high exposed men of myeloid leukaemias (HR 1.31, 95% CI 1.02–1.67), and AML (HR 1.26, 95%CI 0.93–1.70). If workers had been high exposed during their vocational training and at both censuses, these HR increased to 2.24 (95%CI 0.91–5.53) and 2.75 (95%CI 1.11–6.83), respectively. Conclusions Our analysis provided no convincing evidence for an increased risk of death from a range of hematolymphopoietic cancers in workers exposed to high or medium levels of ELF magnetic fields. However, we observed an increased risk of acute myeloid leukaemia in workers exposed to high levels for a longer duration. Observed risks are in line with meta-analysed previous reports on ELF-MF exposure and AML risk, with a summary relative risk of 1.21 (95%CI 1.08–1.37). [ABSTRACT FROM AUTHOR]

Purpose: We aimed to determine whether varying the magnetic field during magnetic resonance imaging would affect the development of chicken embryos and neural tube defects.Methods: Following incubation for 24 h, we exposed chicken embryos to varying magnetic fields for 10 min to assess the impact on development. Three magnetic resonance imaging devices were used, and the eggs were divided into four groups: group 1 is exposed to 1 T, group 2 is exposed to 1.5 T, group 3 is exposed to 3 T, and group 4, control group, was not exposed to magnetic field. After MRI exposure, all embryos were again put inside incubator to complete 48 h. “The new technique” was used to open eggs, a stereomicroscope was used for the examination of magnified external morphology, and each embryo was examined according to the Hamburger and Hamilton chicken embryo stages. Embryos who had delayed stages of development are considered growth retarded. Growth retardation criteria do not include small for stage.Results: Compared with embryos not exposed to a magnetic field, there was a statistically significant increase in the incidence of neural tube closure defects and growth retardation in the embryos exposed to magnetic fields (p < 0.05). However, although the incidence of neural tube closure defects was expected to increase as exposure (tesla level) increased, we found a higher rate of defects in the 1.5-T group compared with the 3-T group. By contrast, the highest incidence of growth retardation was in the 3-T group, which was consistent with our expectation that growth retardation would be more likely as tesla level increased.Conclusions: We therefore conclude that the use of magnetic resonance imaging as a diagnostic tool can result in midline closure defects and growth retardation in chicken embryos. We hypothesize that this may also be true for human embryos exposed to MRI. If a pregnant individual is to take an MRI scan, as for lumbar disc disease or any other any other reason, our results indicate that consideration should be given to an avoidance of MRI during pregnancy. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) machines have horizontal or upright static magnetic field (SMF) of 0.1-3 T (Tesla) at sites of patients and operators, but the biological effects of these SMFs still remain elusive. We examined 12 different cell lines, including 5 human solid tumor cell lines, 2 human leukemia cell lines and 4 human non-cancer cell lines, as well as the Chinese hamster ovary cell line. Permanent magnets were used to provide 0.2-1 T SMFs with different magnetic field directions. We found that an upward magnetic field of 0.2-1 T could effectively reduce the cell numbers of all human solid tumor cell lines we tested, but a downward magnetic field mostly had no statistically significant effect. However, the leukemia cells in suspension, which do not have shape-induced anisotropy, were inhibited by both upward and downward magnetic fields. In contrast, the cell numbers of most non-cancer cells were not affected by magnetic fields of all directions. Moreover, the upward magnetic field inhibited GIST-T1 tumor growth in nude mice by 19.3% (p < 0.05) while the downward magnetic field did not produce significant effect. In conclusion, although still lack of mechanistical insights, our results show that different magnetic field directions produce divergent effects on cancer cell numbers as well as tumor growth in mice. This not only verified the safety of SMF exposure related to current MRI machines but also revealed the possible antitumor potential of magnetic field with an upward direction. [ABSTRACT FROM AUTHOR]

All the living organisms originate, evolve and live under geomagnetic field (GMF, 20-70 µT). With rapid development in science and technology, exposure to various static magnetic fields (SMFs) from natural and man-made sources remains a public environmental topic in consideration of its probable health risk for humans. Many animal studies related to health effect have demonstrated that SMF could improve bone formation and enhance bone healing. Moreover, most of the studies focused on local SMF generated by rod-type magnet. It was difficult to come to a conclusion that how SMF affected bone metabolism in mice. The present study employed hypomagnetic field (HyMF, 500 nT), and moderate SMF (MMF, 0.2 T) to systematically investigate the effects of SMF with continuous exposure on microstructure and mechanical properties of bone. Our results clearly indicated that 4-week MMF exposure did not affect bone biomechanical properties or bone microarchitecture, while HyMF significantly inhibited the growth of mice and elasticity of bone. Furthermore, mineral elements might mediate the biological effect of SMF. [ABSTRACT FROM AUTHOR]

The influence of the previously recorded geomagnetic storm (GS) on human cardiovascular system and microcirculation has been studied under laboratory conditions. Healthy volunteers in lying position were exposed under two artificially created conditions: quiet (Q) and storm (S). The Q regime playbacks a noise-free magnetic field (MF) which is closed to the natural geomagnetic conditions on Moscow’s latitude. The S regime playbacks the initially recorded 6-h geomagnetic storm which is repeated four times sequentially. The cardiovascular response to the GS impact was assessed by measuring capillary blood velocity (CBV) and blood pressure (BP) and by the analysis of the 24-h ECG recording. A storm-to-quiet ratio for the cardio intervals (CI) and the heart rate variability (HRV) was introduced in order to reveal the average over group significant differences of HRV. An individual sensitivity to the GS was estimated using the autocorrelation function analysis of the high-frequency (HF) part of the CI spectrum. The autocorrelation analysis allowed for detection a group of subjects of study which autocorrelation functions (ACF) react differently in the Q and S regimes of exposure. [ABSTRACT FROM AUTHOR]

Compact arrays of permanent magnets have shown promise as replacements for electromagnets in applications requiring magnetic cusps and mirrors. An adjustable system capable of suspending and translating a pair of light, nonmagnetic chassis carrying such sources of magnetic field has been designed and constructed. Using this device to align two cylindrical chassis, strong solenoid-like domains of field, as well as classic biconic cusp and magnetic mirror topologies, are generated. Employing a pair of ring-shaped chassis instead, the superposition of their naturally-emitted cusps is demonstrated to produce sextupolar and octupolar magnetic fields. [ABSTRACT FROM AUTHOR]

Light trapping at the Dirac point in 2D plasma photonic crystal has been obtained. The new localized mode, Dirac mode, is attributable to neither photonic bandgap nor total internal reflection. It exhibits a unique algebraic profile and possesses a high-Q factor resonator of about 1 0 5 . The Dirac point could be modulated by tuning the filling factor, plasma frequency and plasma cyclotron frequency, respectively. When a magnetic field parallel to the wave vector is applied, Dirac modes for right circularly polarized and left circularly polarized waves could be obtained at different frequencies, and the Q factor could be tuned. This property will add more controllability and flexibility to the design and modulation of novel photonic devices. It is also valuable for the possibilities of Dirac modes in photonic crystal containing other kinds of metamaterials. [ABSTRACT FROM AUTHOR]

Human exposure to extremely low frequency magnetic fields (ELF-MF) at 50 Hz is still a topic of great interest due to the possible correlation with childhood leukaemia. The estimation of induced electric fields in human tissues exposed to electromagnetic fields (EMFs) strictly depends on several variables which include the dielectric properties of the tissues. In this paper, the influence of the conductivity assignment to foetal tissues at different gestational ages on the estimation of the induced electric field due to ELF-MF exposure at 50 Hz has been quantified by means of a stochastic approach using polynomial chaos theory. The range of variation in conductivity values for each foetal tissue at each stage of pregnancy have been defined through three empirical approaches and the induced electric field in each tissue has been modelled through stochastic dosimetry. The main results suggest that both the peak and median induced electric fields in foetal fat vary by more than 8% at all gestational ages. On the contrary, the electric field induced in foetal brain does not seem to be significantly affected by conductivity data changes. The maximum exposure levels, in terms of the induced electric field found in each specific tissue, were found to be significantly below the basic restrictions indicated in the ICNIRP Guidelines, 2010. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs) are used as contrast agents and targeted drug delivery systems (TDDS) due to their favorable size, surface charge, and magnetic properties. Unfortunately, the toxicity associated with MNPs limits their biological applications. Surface functionalization ofMNPswith selective polymers alters the surface chemistry to impart better biocompatibility. We report the preparation of surface functionalized MNPs using iron oxide NPs (MNPs), poly (lactic-co-glycolic acid) (PLGA), and sodium alginate via co-precipitation, emulsification, and electro-spraying, respectively. The NPs are in the nanosize range and negatively charged. Morphological and structural analyses affirm the surface functionalized nanostructure of the NPs. The surface functionalized MNPs are biocompatible, and demonstrate enhanced intracellular delivery under an applied magnetic field (H), which evinces the targeting ability of MNPs. After NP treatment, the physico-mechanical properties of fibroblasts are decided by the selectiveMNPuptake under "on" or "off" magnetic field conditions. We envision potential use of biocompatible surface functionalized MNP for intracellular-, targeted-DDS, imaging, and for investigating cellular mechanics. [ABSTRACT FROM AUTHOR]

Present study strives to perform a rigorous exploration of dynamic dipole polarizability (DDP) of G a A s quantum dot (QD) containing dopant with special reference to influence of Gaussian white noise. Several physical quantities have been varied over a range to observe the modulations of the DDP profiles. Aforesaid physical quantities include magnetic field, confinement potential, dopant location, dopant potential, noise strength, aluminium concentration (only for A l x G a 1 − x A s alloy QD), position-dependent effective mass (PDEM), position-dependent dielectric screening function (PDDSF), anisotropy, hydrostatic pressure (HP) and temperature. The DDP profiles reveal noticeable characteristics governed by the particular physical quantity involved, presence/absence of noise, the manner (additive/multiplicative) noise is applied to the system and the incoming photon frequency. As a general observation we have found that additive noise causing greater deviation of the DDP profile from noise-free state than its multiplicative neighbor. The study highlights viable means of harnessing DDP of doped QD under the governance of noise by appropriate adjustment of several relevant factors. The study merits importance in the light of technological applications of QD-based devices where noise appears as an integral component. [ABSTRACT FROM AUTHOR]

Type 1 diabetes mellitus (T1DM) has been associated with deterioration of bone microarchitecture and strength, resulting in increased fracture risk. Substantial studies have revealed the capacity of moderate-intensity static magnetic fields (SMF) on promoting osteoblastogenesis in vitro and stimulating bone growth and bone regeneration in vivo, whereas it is unknown whether SMF can resist T1DM-associated osteopenia/osteoporosis. We herein investigated the potential effects of whole-body SMF exposure with 4 mT on bone loss in streptozotocin-induced T1DM rats. We found that SMF exposure for 16 weeks inhibited architectural deterioration of trabecular bone and cortical bone and mechanical strength reduction in T1DM rats, as evidenced by the MicroCT and 3-point bending findings. Our serum biochemical, bone histomorphometric and PCR results revealed that SMF induced higher serum osteocalcin, mineral apposition rate and osteoblast number of trabecular bone, and higher skeletal osteocalcin, BMP2 and Runx2 gene expression in T1DM rats, whereas SMF showed no significant alteration in serum CTX, skeletal osteoclast number, or osteoclastogenesis-related RANKL-RANK signaling gene expression. Together, our findings suggest that moderate SMF prevented bone architectural deterioration and strength reduction by inhibiting the reduction of bone formation in T1DM rats, and indicate that SMF might become a promising biophysical countermeasure for T1DM-related osteopenia/osteoporosis. [ABSTRACT FROM AUTHOR]

Precise control of particles co-assembly has attracted great attention for fabricating intricate structures and functional materials. However, achieving precise coassembly of one-dimensional (1D) binary superstructures remains challenging due to the constrained thermodynamic stability and lack of general strategies to control the 1D ordered arrangement of mixed particles. Here, we propose a facile strategy to achieve programmed coassembly of 1D binary superstructures by liquid soft confinement without particle modification or external field. It reveals that binary particles undergo stepwise confinement and programmed co-assembly in the gradually shrinking and spatially tunable liquid soft confinement. Through tuning the liquid confined space and particles composition, diverse 1D binary superstructures with precisely controlled periodicity, orientation and symmetry are achieved, which shows generality for various particles of di�€erent sizes and materials. This work provides a promising route to refined patterning and manufacturing complex materials. [ABSTRACT FROM AUTHOR]

Surface morphology i.e. surface roughness, surface texture, and surface wettability is a necessary requirement to lengthen implant’s life and also to increase its performance. The requirement of surface morphology of each implant varies depending upon its applications. In the present study, a nanofinishing process, Magnetic Field Assisted Finishing is used to generate different surface morphologies on the bio-titanium alloy. For this purpose, different magnetorheological fluids are synthesized by changing fluid composition to finish bio-titanium alloy using novel magnetic field assisted finishing tool. Further, the surface characteristics of the polished surfaces with different magnetorheological fluids are characterized for surface roughness, surface texture and to confirm their surface wettability (i.e. whether the surface is hydrophilic or hydrophobic). Ultrafine surface roughness (Ra = 10 nm) is achieved using magnetorheological fluid of Type - I having very smooth surface topography. While little bit rough surface (Ra = 70 nm) and less smooth surface topography is obtained using Type - II magnetorheological fluid. Experimentally it is observed that bio-titanium polished surface using magnetorheological fluid with Type - I polishing medium is hydrophilic in nature and it is better suited for semi-permanent type of implants and also for implants which engaged with relative motion in human body. While, magnetorheological fluid of type II should be selected to polish permanent implants which requires hydrophobic surface. [ABSTRACT FROM AUTHOR]

Based on the mechanism of temperature shock treatment and electromagnetic effect for food preservation, this paper developed a novel food preservation method by combining static magnetic field with low magnetic flux density and low-temperature water shock to process the fresh postharvest vegetable. Compared with the single cold-water shock treatment (CST, T w = 2 °C, τ = 40 min), the static magnetic field and cold-water shock treatment (SMCT, B = 70 Gs, T w = 2 °C, τ = 40 min) caused an increase of cooling-rate of cucumbers' tissues during treatment. Weight loss of SMCT was also lower than that of CST during storage. Furthermore, decay incidence and color difference of SMCT were about 40.2% and 10.6% lower than that of CST. Activities of catalase and superoxide dismutase for SMCT were higher than that of CST, which caused a reduction of malondialdehyde. Experimental results confirmed that SMCT had a positive influence on pre-cooling, preservation quality and physicochemical properties of cucumbers. [ABSTRACT FROM AUTHOR]

Existence of magnetic field causes heat transfer to reduce in free convection but in several engineering uses for example: electronic application; enhancing heat transfer is a purpose. Thus, nanofluid should be selected as working fluid. Nanofluid is dispersion of very small metal particles in the base fluid. Two phase and single phase are two ways for estimating the behavior of nanofluid. At first model, nanofluid suppose as homogenous fluid without any slip mechanism. But in second method, slip velocities are included. Brownian motion and Thermophoresis impacts are taken into consideration in second approach. In this paper, previous publications about nanofluid hydrothermal treatment in existence of magnetic field are reviewed. Rely of variable and constant magnetic fields, Ferrohydrodynamic (FHD) and Magnetohydrodynamic (MHD) can take role in simulations. Numerical and analytical methods are considered by authors. Results proved that temperature gradient augments with augment of solid particle concentration and buoyancy forces, while it decreases with augment of magnetic field. [ABSTRACT FROM AUTHOR]

In this work, we have shown for the first time that Microbacterium maritypicum CB7 bacterium is capable to use Benzo( a )Pyrene as a sole source of carbon and energy. We followed the growth kinetics of M. maritypicum CB7 in minimum medium supplemented with 10 mg/l Benzo( a )Pyrene for 30 days. The results obtained showed that M. maritypicum CB7 strain is able to degrade 69% of the initial amount of BaP. In order to improve the rate of biodegradation, we tested for 5 days the effect of a static magnetic field (SMF) at different inductions (50, 100 and 200 mT) on the degradation kinetics of Benzo( a )Pyrene by M. maritypicum CB7. Indeed, at 200 mT, we observed an increase of the yield by the twice of Benzo( a )Pyrene biodegradation rate compared to the non-induced sample. This study shows the important potential of M. maritypicum CB7 for the bioremediation of Benzo( a )Pyrene in the environment and the importance of the application of a SMF to yield the performance of the process suggesting its potential application in bioremediation of polluted sites with hydrocarbons compounds. [ABSTRACT FROM AUTHOR]

Studies the effects of a nonuniform magnetic field on the germination of plants. Experimental details; Results and discussion.

Presents information on a study which examined the effects of magnetic and electric orientations of human erythrocyte on blood flow. Methodology used; Results and discussion; Conclusions.

This paper aims at the global regularity of solutions to the two-dimensional (2D) incompressible magneto-micropolar equations with partial dissipation. We are able to deal with two partial dissipation cases and establish the global regularity of solutions for each case. [ABSTRACT FROM AUTHOR]

Spinal cord injury (SCI) is insult to the spinal cord, which results in loss of sensory and motor function below the level of injury. SCI results in both immediate mechanical damage and secondary tissue degeneration. Following traumatic insult, activated microglia release proinflammatory cytokines and excess iron due to hemorrhage, initiating oxidative stress that contributes to secondary degeneration. Literature suggests that benefits are visible with the reduction in concentration of iron and activated microglia in SCI. Magnetic field attenuates oxidative stress and promotes axonal regeneration in vitro and in vivo. The present study demonstrates the potential of extremely low frequency magnetic field to attenuate microglia- and iron-induced secondary injury in SCI rats. Complete transection of the spinal cord (T13 level) was performed in male Wistar rats and subsequently exposed to magnetic field (50 Hz,17.96 µT) for 2 h daily for 8 weeks. At the end of the study period, spinal cords were dissected to quantify microglia, macrophage, iron content and study the architecture of lesion site. A significant improvement in locomotion was observed in rats of the SCI + MF group as compared to those in the SCI group. Histology, immunohistochemistry and flow cytometry revealed significant reduction in lesion volume, microglia, macrophage, collagen tissue and iron content, whereas, a significantly higher vascular endothelial growth factor expression around the epicenter of the lesion in SCI + MF group as compared to SCI group. These novel findings suggest that exposure to ELF-MF reduces lesion volume, inflammation and iron content in addition to facilitation of angiogenesis following SCI. [ABSTRACT FROM PUBLISHER]

Reactive oxygen species (ROS) ubiquitously exist in mammalian cells to participate in various cellular signaling pathways. The intracellular ROS levels are dependent on the dynamic balance between ROS generation and elimination. In this review, we summarize reported studies about the influences of magnetic fields (MFs) on ROS levels. Although in most cases, MFs increased ROS levels in human, mouse, rat cells, and tissues, there are also studies showing that ROS levels were decreased or not affected by MFs. Multiple factors could cause these discrepancies, including but not limited to MF type/intensity/frequency, exposure time and assay time-point, as well as different biological samples examined. It will be necessary to investigate the influences of different MFs on ROS in various biological samples systematically and mechanistically, which will be helpful for people to get a more complete understanding about MF-induced biological effects. In addition, reviewing the roles of MFs in ROS modulation may open up new scenarios of MF application, which could be further and more widely adopted into clinical applications, particularly in diseases that ROS have documented pathophysiological roles. [ABSTRACT FROM AUTHOR]

Silicon photomultipliers are a novel technology for the detection of photons in near ultraviolet, visible, and near-infrared spectral ranges. Their application is rapidly growing and extending to many fields in physics, replacing traditional PMTs and APDs. In this study a large-size CsI(Tl) crystal coupled to small-area SiPM ( 3 × 3 mm 2 ) was used to detect α -particles and low energy protons. In particular, the detector was irradiated with proton beams accelerated by the Tandem Van-der-Graff of the INFN-Laboratori Nazionali del Sud (LNS), at incident energies between 2.5 MeV and 24 MeV. The detector performance was studied in terms of light yield, linearity and energy resolution. In addition, we investigated the dependence of the detector response on the impact point of the particles. [ABSTRACT FROM AUTHOR]

We revisit the precision of the measurement of track parameters (position, angle) with optimal methods in the presence of detector resolution, multiple scattering and zero magnetic field. We then obtain an optimal estimator of the track momentum by a Bayesian analysis of the filtering innovations of a series of Kalman filters applied to the track. This work could pave the way to the development of autonomous high-performance gas time-projection chambers (TPC) or silicon wafer γ -ray space telescopes and be a powerful guide in the optimization of the design of the multi-kilo-ton liquid argon TPCs that are under development for neutrino studies. [ABSTRACT FROM AUTHOR]

Detailed assessment of exposure to extremely low frequency (ELF) and intermediate frequency (IF) fields is essential in order to conduct informative epidemiological studies of the health effects from exposure to these fields. There is limited information available regarding ELF electric fields and on both magnetic and electric field exposures of children in the IF range. The aim of this study was to characterize ELF and IF exposure of children in the Spanish INMA cohort. A combination of spot and fixed measurements was carried out in 104 homes, 26 schools and their playgrounds and 105 parks. Low levels of ELF magnetic fields (ELF-MF) were observed (with the highest 24-h time-weighted average (TWA) exposure being 0.15 μT in one home). The interquartile range (IQR) of ELF electric fields (ELF-EF) ranged from 1 to 15 V/m indoors and from 0.3 to 1.1 V/m outdoors and a maximum value observed was 55.5 V/m in one school playground. IQR ranges for IF magnetic and electric fields were between 0.02 and 0.23 μT and 0.2 and 0.5 V/m respectively and maximum values were 0.03 μT and 1.51 V/m in homes. Correlations between magnetic and electric fields were weak for ELF (Spearman 0.04–0.36 in different settings) and moderate for IF (between 0.28 and 0.75). Children of INMA-Gipuzkoa cohort were exposed to very low levels of ELF-MF in all settings and to similar levels of ELF-EF compared to the range of previously reported levels, although somewhat higher exposures occurred at home. Children enrolled to our study were similarly exposed to IF in all settings. [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]

Purpose:To evaluate the effect of static magnetic fields (SMFs) on insulin secretion and explore the mechanisms underlying exposure to SMF-induced insulin secretion in rat insulinoma INS-1 cells. Materials and methods:INS-1 cells were exposed to a 400 mT SMF for 72 h, and the proliferation of INS-1 cells was detected by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The secretion of insulin was measured with an enzyme linked immunosorbent assays (ELISA), the expression of genes was detected by real-time PCR, and the expression of proteins was measured by Western blotting. Results:Exposure to an SMF increased the expression and secretion of insulin by INS-1 cells but did not affect cell proliferation. Moreover, SMF exposure up-regulated the expression of several pancreas-specific transcriptional factors. Specifically, the activity of the rat insulin promoter was enhanced in INS-1 cells exposed to an SMF, and the expression levels of synaptosomal-associated protein 25 (SNAP-25) and syntaxin-1A were up-regulated after exposure to an SMF. Conclusions:SMF exposure can promote insulin secretion in rat INS-1 cells by activating the transcription of the insulin gene and up-regulating the expression of vesicle-secreted proteins. [ABSTRACT FROM AUTHOR]

Diverse animals ranging from worms and insects to birds and turtles perform impressive journeys using the magnetic field of the earth as a cue. Although major cellular and molecular mechanisms for sensing mechanical and chemical cues have been elucidated over the past three decades, the mechanisms that animals use to sense magnetic fields remain largely mysterious. Here we survey progress on the search for magnetosensory neurons and magnetosensitive molecules important for animal behaviors. Emphasis is placed on magnetosensation in insects and birds, as well as on the magnetosensitive neuron pair AFD in the nematode Caenorhabditis elegans. We also review conventional criteria used to define animal magnetoreceptors and suggest how approaches used to identify receptors for other sensory modalities may be adapted for magnetoreceptors. Finally, we discuss prospects for underutilized and novel approaches to identify the elusive magnetoreceptors in animals. [ABSTRACT FROM AUTHOR]

The kinetic spin-3/2 Ising system in the presence of crystal and external oscillating magnetic fields on the triangular lattice (TL) is examined within the mean-field approximation and the Glauber-type stochastic dynamics, namely dynamic mean-field approximation (DMFA). First, the dynamic equations describing the behavior of the system are derived for the TL. Then, the dynamic equations are solved numerically to obtain the dynamic hysteresis curves of the kinetic spin-3/2 Ising ferromagnetic system, which strongly depend on the Hamiltonian parameters. Moreover, the dynamic behaviors of the coercivity and remanent magnetizations are studied depending on the temperature, crystal field and frequency of the oscillating external magnetic field. Finally, the results are compared with some experimental and theoretical studies and a qualitatively good overall agreement is observed [ABSTRACT FROM AUTHOR]

Long-time exposure to galactic cosmic rays is one of the most problematic threats for a manned mission in the deep space. In the last decades, several studies of active superconducting magnetic shields were performed leading to the proposals of apparently promising magnetic configurations. However, as the interaction of energetic particles with the materials composing the magnets was not taken into account, the contribution of secondary particles to the astronauts’ radiation dose was neglected, and, consequently, the actual effectiveness of the shields was overestimated. In the frame of the EU-FP7-SR2S project, a study of superconducting space radiation shield was performed associating the optimization of the magnetic configuration with Monte–Carlo simulation of the dose reduction. It was found that most of the magnetic shields proposed in previous works are not adequate, and a novel configuration, transparent to radiation, was proposed based on toroids arranged with their axes perpendicular to the spacecraft axis. Compared to other shields with the same shielding power, such a configuration results in lower magnetic field at the superconductor and very light design. [ABSTRACT FROM PUBLISHER]

Objectives: The engine and power supply of trains in advanced rail transit systems is electric (Alternating current (AC) or Direct current (DC)). Such systems generate magnetic fields in the range of static or extremely low frequencies. This study aims to assess occupational exposure of train drivers to Static Magnetic Field (SMF) and Extremely Low Frequency Magnetic Field (ELF-MF). Methods: In total, 7 trains were randomly selected from intercity and metro lines. Based on the BS EN 50500:2008 method recommendations, magnetic fields were measured by the TES-1394 (ELF-MF meter) and HI-3550 (SMF meter). The exposure of drivers was assessed in accordance with of ACGIH-TLVs. The independent sample T-test, Paired samples T-test, one-way ANOVA (with LSD post hoc), and Mann--Whitney nonparametric test were used for data analysis. Results: Mean (±SD) value of ELF-MF and SMF were measured 1.47 (±1.67) µT and <0.1 mT in the intercity AC trains, 0.45 (±0.53) µT and 0.95 (±0.075) mT in the AC trains, and 0.35 (±0.22) µT and 0.081 (±0.86) mT in the DC trains. In addition, maximum exposure to ELF-MF and SMF were 9 µT in intercity AC trains and 1 mT in DC trains, respectively. Conclusions: Totally, in none of the situations, exposure of train drivers to ELF-MF and SMF exceeded the ACGIH-TLVs. This does not mean that these magnetic fields are safe and harmless. Hence, the clinical and/or epidemiological study, along with an ELF-MF and SMF exposure assessment of all railway personals, can be helpful for prevention, identification and treatment of diseases. [ABSTRACT FROM AUTHOR]

The ATP pool in Escherichia coli is a magnetic-dependent characteristic of microorganism vital activity. It depends on the values of the external static magnetic field and the existence of magnetic moment of magnesium isotopes nuclei added to the growth nutrient medium. The combined effects of the magnetic field 70-95 mT and magnesium magnetic isotope Mg on E. coli bacteria leads to increase intracellular concentration of ATP. Magnetic-field effects in the range of 0.8-16 mT, registered for all bacteria regardless of the magnesium-isotopic enrichment of nutrient medium, evidence about the sensitivity of intracellular processes to weak magnetic fields. [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]

Within carbon suboxide C 2 O devised from ab initio in ground state two-dimensional structure, finite spin polarization is demonstrated, leading to a stable ferromagnetic order confirmed for simple and superstructure cells. Specifically structural relaxation of C 2 O in 2D AlB 2 -type structure shows that the hexagonal crystal symmetry is maintained with a large c/a ratio letting magnetization develop on oxygen p valence states. Band-like O-p x,y and localized-like O-p z spin projected density of states show striking resemblance with Cr-d in well known room temperature CrO 2 ferromagnet with band gap opening in majority spin states leading to an integer magnetic moment of 2 μ B and a strongly ferromagnetic behavior in the ground state. [ABSTRACT FROM AUTHOR]

The current study describes properties of bacterial cellulose (BC) obtained fromKomagataeibacter xylinuscultures exposed to the rotating magnetic field (RMF) of 50 Hz frequency and magnetic induction of 34 mT for controlled time during 6 days of cultivation. The experiments were carried out in the customized RMF exposure system adapted for biological studies. The obtained BC displayed an altered micro-structure, degree of porosity, and water-related parameters in comparison to the non-treated, control BC samples. The observed effects were correlated to the duration and the time of magnetic exposure duringK. xylinuscultivation. The most preferred properties in terms of water-related properties were found for BC obtained in the setting, where RMF generator was switched off for the first 72 h of cultivation and switched on for the next 72 h. The described method of BC synthesis may be of special interest for the production of absorbent, antimicrobial-soaked dressings and carrier supports for the immobilization of microorganisms and proteins. [ABSTRACT FROM PUBLISHER]

It has been established that living things are sensitive to extremely low-frequency magnetic fields at vanishingly small intensities, on the order of tens of nT. We hypothesize, as a consequence of this sensitivity, that some fraction of an individual’s central nervous system activity can be magnetically detected by nearby individuals. Even if we restrict the information content of such processes to merely simple magnetic cues that are unconsciously received by individuals undergoing close-knit continuing exposure to these cues, it is likely that they will tend to associate these cues with the transmitting individual, no less than would occur if such signals were visual or auditory. Furthermore, following what happens when one experiences prolonged exposure to visual and like sensory inputs, it can be anticipated that such association occurring magnetically will eventually also enable the receiving individual to bond to the transmitting individual. One can readily extrapolate from single individuals to groups, finding reasonable explanations for group behavior in a number of social situations, including those occurring in families, animal packs, gatherings as found in concerts, movie theaters and sports arenas, riots and selected predatory/prey situations. The argument developed here not only is consistent with the notion of a magnetic sense in humans, but also provides a new approach to electromagnetic hypersensitivity, suggesting that it may simply result from sensory overload. [ABSTRACT FROM PUBLISHER]

Although cardiac activity is known to differ between species in many respects, most evaluations of the cardiac effects of low-frequency electric and magnetic fields, which have a stimulant effect on electrically activated cells, have been performed in non-human experimental animals and cells, and the effects in humans have been assessed using theoretical models. In recent years, it has been veri- fied that human cardiomyocytes differentiated from human induced pluripotent stem cells (hiPS-CM) are useful for evaluating human responses to various cardioactive compounds. In this study, we applied hiPSCMs for the first time to evaluate the human cardiac effects of power-frequency magnetic fields (MFs). After preparation of hiPS-CMs, we subjected a hiPS-CM monolayer formed on a multi-electrode array to short-term exposure to a 50 Hz MF at 400 mT with recording of the extracellular field potentials. The field potential duration of the hiPS-CMs did not differ significantly pre- and post-exposure, indicating that under these conditions, exposure to a 50 Hz MF at 400 mT does not affect the electrical activity of hiPSCMs. [ABSTRACT FROM AUTHOR]

Magnetron-sputtering inert-gas condensation is an emerging technique offering single-step, chemical-free synthesis of nanoparticles with well-defined morphologies optimized for specific applications. In this study, the authors report a flexible approach to produce Fe nanocubes as building blocks for high-performance NO2 gas sensor devices, and hybrid FeAu nanocubes with magneto-plasmonic properties. Considering that nucleation happens within a short distance from the sputtering target, the authors utilize the high-permeability and resultant screening effect induced by magnetic Fe targets of various thicknesses to manipulate the magnetic field configuration and plasma confinement. The authors thus readily switch from bimodal to single-Gaussian size distributions of Fe nanocubes by modifying their primordial thermal environments, as explained by a combination of modeling methods. Simultaneously, the authors obtain a material yield increase of more than one order of magnitude compared to experiments using postgrowth mass filtration. The effectiveness of the method is demonstrated by the deposition of Fe nanocubes on microhotplate devices, leading to unprecedented NO2 detection performance for Fe-based chemoresistive gas sensors. The exceedingly low detection limit down to 3 ppb is attributed to a morphological change in operando from Fe/Fe-oxide core/shell to specific hollow-nanocube structures, as revealed by in situ environmental transmission electron microscopy. [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 aim of this work was to investigate the effects of 0.5T static magnetic field (sMF) on the viability and proliferation rate of human adipose-derived mesenchymal stromal stem cells (hASCs) via activation of the phosphoinositide 3-kinase/Akt (PI3K/Akt) signaling pathway. In a 7-d culture we examined cell growth kinetic and population doubling time (PDT). We also examined cell morphology and the cellular senescence markers level. Exposure to sMF enhanced the viability of these cells. However, the effect was blocked by treating the cells with LY294002, a P13K inhibitor. We compared this effect by Western Blot analysis of Akt protein expression. We also examined whether the cell response on sMF stimulation is dependent on integrin engagement and we measured integrin gene expression. Our results suggest that stimulation using sMF is a viable method to improve hASC viability. sMF is involved in mechanisms associated with controlling cell proliferative potential signaling events. [ABSTRACT FROM AUTHOR]