Low Frequency Magnetic Fields Research Articles

Analysis of effect of pump light wavelength on the magnetic noise suppression of the SERF co-magnetometer

Spin Exchange Relaxation-Free Co-Magnetometer (SERFCM) possesses ultra-sensitive rotation measurement capabilities, offering broad application prospects in inertial navigation and fundamental physics research. Precision of SERFCM in rotation measurements is directly influenced by its ability to suppress magnetic noise. In this study, a state-space method is used to establish a SERFCM response model, considering the effect of pump light wavelength. An analysis is conducted to assess the effect of pump light wavelength detuning on the ability to suppress magnetic noise of SERFCM. Theoretical results indicate that detuned pump light wavelength can effectively reduce the magnetic field gradient generated by atomic polarization, thereby improving overall system performance. Experimental validation demonstrates that a slight detuning of the pump light wavelength results in a 21% improvement in the ability to suppress low-frequency magnetic fields.

Bio-Interaction Mechanism of Occupational Extremely Low-Frequency Magnetic Field and its Potential Effects on Human

Human lifestyle is evolving as a result of advancement in technology which is mainly driven by electricity. The presence of extremely low frequency magnetic field in the Earth’s atmosphere produced during the processes of generation, transmission and distribution of electricity in occupational environment has the ability to penetrate human skin, and is potentially hazardous to health of exposed individual, which have become a source of concern. This article presents state of knowledge on the electrical and dielectric properties of human tissues, examine the various phenomena processes during the bio-interaction mechanism, all-inclusive biological effects process explained and identify potential health risk associated with prolonged and excessive exposure to occupational magnetic field at extremely low frequency in addition to the underlining factors that influence the probable threats.

The Effect of Extremely Low-Frequency Magnetic Field on Stroke Patients: A Systematic Review

Background: The aim of this study was to review the current state of scientific evidence on the effect of extremely low-frequency magnetic fields stimulation (ELF-MFs) on stroke patients. Methods: A systematic review of PubMed, ScienceDirect, PeDro and Embase databases was conducted. Only articles published in English, involving adult participants and focusing on individuals who had experienced a stroke, specifically examining the impact of ELF-MFs on post-stroke patients and had well-defined criteria for inclusion and exclusion of participants, were included. The methodological quality of the included studies was assessed using the Quality Assessment Tool for Quantitative Studies (QATQS). Results: A total of 71 studies were identified through database and reference lists’ search, from which 9 were included in the final synthesis. All included studies showed a beneficial effect of ELF-MFs on stroke patients, however seven of the included studies were carried by the same research group. Improvements were observed in domains such as oxidative stress, inflammation, ischemic lesion size, functional status, depressive symptoms and cognitive abilities. Conclusions: The available literature suggests a beneficial effect of ELF-MFs on post-stroke patients; however, the current data are too limited to broadly recommend the use of this method. Further research with improved methodological quality is necessary.

Effect of rmEGF combined with ELF-EMF on promoting wound healing in rats.

The process of wound healing is complex, and expediting it remains a challenge. The advantages of extremely low frequency electric and magnetic fields (ELF-EMF) are its non-invasive treatment, promotes healing and promotes myogenesis of C2C12 cells. Epidermal growth factor (EGF) is known to play a vital role in promoting wound healing, so a combination of ELF-EMF and EGF can have far-reaching significance. To study the effect of recombinant murine epidermal growth factor (rmEGF) combined with ELF-EMF on wound healing. Thirty-six rats were randomly divided into three groups: normal control group, EGF group, and ELF-EMF+EGF group, and a 20 mm × 20 mm dorsal wound was made. The wound healing rate of rats was calculated on the 3rd, 7th, 11th and 15th day. HE staining was used to observe the micro-morphological changes during the wound healing process. The wound healing rate of EGF+ELF-EMF group was better than other groups. On the 15th day of wound healing, the wounds of each group were completely healed. On the 3rd, 7th, 11th and 15th day of HE staining, the early inflammatory cell infiltration, the arrangement of fibroblasts and the number of new capillaries in the wounds of EGF+ELF-EMF group were better than those of the other groups. rmEGF combined with ELF-EMF significantly promotes wound healing in SD rats.

New developments in cosmetic applications of electromagnetic fields: Client and occupational hazard assessment.

Energy-based devices are used to improve features of appearance for aesthetic reasons while avoiding more invasive methods. Examples of treatment targets are the reduction of wrinkles, sagging, unwanted skin lesions, body hair and excess fatty tissue, and the enhancement of muscle tissue. One treatment modality is the use of electromagnetic fields (EMF, 0‒300 GHz). The present work aims to give an up-to-date survey of cosmetic applications of EMF for professional use with an assessment of client and worker exposure and possible adverse effects. A systematic search was conducted for peer-reviewed articles (2007-2022), patents, premarket notifications, manufacturer data, and adverse effects reports. Five categories of cosmetic EMF device with increasing frequency were identified: sinusoid low frequency magnetic fields for lipolysis; pulsed low frequency magnetic fields for skin rejuvenation; pulsed low frequency magnetic fields for muscle building; radiofrequency EMF for lipolysis or skin rejuvenation; microwaves for hair removal or hyperhidrosis. In the vicinity of the last four device categories, there is a potential for exceeding the occupational exposure limits in the European Union EMF Directive, which could lead to nerve or muscle stimulation, burns or overheating. There are also potential hazards for clients or workers wearing active or passive medical devices. The severity of reported adverse effects increases with EMF frequency.

Effects of low-frequency magnetic field on solubility, structural and functional properties of soy 11S globulin.

Soy 11S globulin has high thermal stability, limiting its application in the production of low-temperature gel foods. In this study, the low-frequency magnetic field (LF-MF, 5 mT) treatment (time, 30, 60, 90, and 120 min) was used to improve the solubility, conformation, physicochemical properties, surface characteristics, and gel properties of soy 11S globulin. Compared with the native soy 11S globulin, the sulfhydryl content, emulsifying capacity, gel strength, water-holding capacity, and absolute zeta potential values significantly increased (P < 0.05) after LF-MF treatment. The LF-MF treatment induced the unfolding of the protein structure and the fracture of disulfide bonds. The variations in solubility, foaming properties, viscosity, surface hydrophobicity, and rheological properties were closely related to the conformational changes of soy 11S globulin, with the optimum LF-MF modification time being 90 min. LF-MF treatment is an effective method to improve various functional properties of native soy 11S globulin, and this study provides a reference for the development of plant-based proteins in the food industry. © 2024 Society of Chemical Industry.

Wireless magnetoelectrically powered organic light-emitting diodes.

Compact wireless light sources are a fundamental building block for applications ranging from wireless displays to optical implants. However, their realization remains challenging because of constraints in miniaturization and the integration of power harvesting and light-emission technologies. Here, we introduce a strategy for a compact wirelessly powered light-source that consists of a magnetoelectric transducer serving as power source and substrate and an antiparallel pair of custom-designed organic light-emitting diodes. The devices operate at low-frequency ac magnetic fields (~100 kHz), which has the added benefit of allowing operation multiple centimeters deep inside watery environments. By tuning the device resonance frequency, it is possible to separately address multiple devices, e.g., to produce light of distinct colors, to address individual display pixels, or for clustered operation. By simultaneously offering small size, individual addressing, and compatibility with challenging environments, our devices pave the way for a multitude of applications in wireless displays, deep tissue treatment, sensing, and imaging.

Investigation of the influence mechanism of shield on the strong magnetic field during electromagnetic launch

The electromagnetic launch process generates low-frequency pulsed magnetic fields with peak values reaching Tesla-levels, imposing greater demands on the interference immunity of electronics within projectiles. However, during the propagation of low-frequency pulsed strong magnetic fields, their characteristics are affected by the shielding properties of the surrounding medium materials, resulting in modifications to the actual internal magnetic fields of the devices. This paper presents a theoretical analysis, numerical simulation, and experimental investigation based on the shielding mechanisms of conductive and magnetic materials to elucidate their impact on the pulsed magnetic fields. Additionally, leveraging previous work on electromagnetic railgun projectile magnetic field calculations, the shielding model is established to determine the shielding effects of different material combinations on the magnetic field during electromagnetic launch. The results reveal that both conductive and magnetic materials influence the amplitude, pulse width, and initiation time of the pulsed magnetic field, a finding validated through dynamic projectile-borne magnetic field testing.

Exposure to Low-Frequency Radiation Changes the Expression of Nestin, VEGF, BCRP and Apoptosis Markers During Glioma Treatment Strategy: An In Vitro Study

Background: Exposure to physical contamination during chemotherapy, including non-ionizing electromagnetic fields, raises concerns about the widespread sources of exposure to this type of radiation. Glioblastoma multiforme (GBM) is an aggressive central nervous system tumor that is hard to treat due to resistance to drugs such as temozolomide (TMZ). Objective: Electromagnetic fields (EMF) and haloperidol (HLP) may have anticancer effects. In this study, we investigated the effects of TMZ, HLP, and EMF on GBM cell lines and analyzed the association between non-ionizing radiation and the risk of change in drug performance. Methods: Cell viability and reactive oxygen species (ROS) generation were measured by MTT and NBT assay, respectively. Then, the expression levels of breast cancer-resistant protein (BCRP), Bax, Bcl2, Nestin, vascular endothelial growth factor (VEGF) genes, and P53, Bax, and Bcl2 Proteins were evaluated by real-time PCR and western blot. Results: Co-treatment of GBM cells by HLP and TMZ enhanced apoptosis in T-98G and A172 cells by increasing the expression of P53 and Bax and decreasing Bcl-2. Interestingly, exposure of GBM cells to EMF decreased apoptosis in the TMZ+HLP group. Conclusion: In conclusion, EMF reduced the synergistic effect of TMZ and HLP. This hypothesis that patients who are treated for brain tumors and suffer from depression should not be exposed to EMF is proposed in the present study. There appears to be an urgent need to reconsider exposure limits for low-frequency magnetic fields, based on experimental and epidemiological research, the relationship between exposure to non-ionizing radiation and adverse human health effects.

Ultra-low frequency magnetic energy focusing for highly effective wireless powering of deep-tissue implantable electronic devices.

The limited lifespan of batteries is a challenge in the application of implantable electronic devices. Existing wireless power technologies such as ultrasound, near-infrared light and magnetic fields cannot charge devices implanted in deep tissues, resulting in energy attenuation through tissues and thermal generation. Herein, an ultra-low frequency magnetic energy focusing (ULFMEF) methodology was developed for the highly effective wireless powering of deep-tissue implantable devices. A portable transmitter was used to output the low-frequency magnetic field (<50Hz), which remotely drives the synchronous rotation of a magnetic core integrated within the pellet-like implantable device, generating an internal rotating magnetic field to induce wireless electricity on the coupled coils of the device. The ULFMEF can achieve energy transfer across thick tissues (up to 20cm) with excellent transferred power (4-15mW) and non-heat effects in tissues, which is remarkably superior to existing wireless powering technologies. The ULFMEF is demonstrated to wirelessly power implantable micro-LED devices for optogenetic neuromodulation, and wirelessly charged an implantable battery for programmable electrical stimulation on the sciatic nerve. It also bypassed thick and tough protective shells to power the implanted devices. The ULFMEF thus offers a highly advanced methodology for the generation of wireless powered biodevices.

Up- and Down-Regulation of Enzyme Activity in Aggregates with Gold-Covered Magnetic Nanoparticles Triggered by Low-Frequency Magnetic Field.

The modern global trend toward sustainable processes that meet the requirements of "green chemistry" provides new opportunities for the broad application of highly active, selective, and specific enzymatic reactions. However, the effective application of enzymes in industrial processes requires the development of systems for the remote regulation of their activity triggered by external physical stimuli, one of which is a low-frequency magnetic field (LFMF). Magnetic nanoparticles (MNPs) transform the energy of an LFMF into mechanical forces and deformations applied to enzyme molecules on the surfaces of MNPs. Here, we demonstrate the up- and down-regulation of two biotechnologically important enzymes, yeast alcohol dehydrogenase (YADH) and soybean formate dehydrogenase (FDH), in aggregates with gold-covered magnetic nanoparticles (GCMNPs) triggered by an LFMF. Two types of aggregates, "dimeric" (with the enzyme attached to several GCMNPs simultaneously), with YADH or FDH, and "monomeric" (the enzyme attached to only one GCMNP), with FDH, were synthesized. Depending on the aggregate type ("dimeric" or "monomeric"), LFMF treatment led to a decrease (down-regulation) or an increase (up-regulation) in enzyme activity. For "dimeric" aggregates, we observed 67 ± 9% and 47 ± 7% decreases in enzyme activity under LFMF exposure for YADH and FDH, respectively. Moreover, in the case of YADH, varying the enzyme or the cross-linking agent concentration led to different magnitudes of the LFMF effect, which was more significant at lower enzyme and higher cross-linking agent concentrations. Different responses to LFMF exposure depending on cofactor presence were also demonstrated. This effect might result from a varying cofactor binding efficiency to enzymes. For the "monomeric" aggregates with FDH, the LFMF treatment caused a significant increase in enzyme activity; the magnitude of this effect depended on the cofactor type: we observed up to 40% enzyme up-regulation in the case of NADP+, while almost no effect was observed in the case of NAD+.

Improving the performance of low-frequency magnetic energy harvesters using an internal magnetic-coupled mechanism

In this study, we present a novel low-frequency magnetic field energy harvester (EH) employing beryllium bronze/Pb(Zr,Ti)O3 ceramic composited dual-beam structures with tip magnets attached to the inner and outer beams. This design incorporates the internal magnetic-coupled (IMC) effect, resulting in significantly enhanced coupling ability and a wide bandwidth. The validity of the IMC mechanism is confirmed through theoretical formulas and numerical simulations. By leveraging the IMC condition, the EH achieves an expanded bandwidth, which increases from 22 to 43 Hz. Moreover, the total output voltages at the inherent resonance and internal resonance are boosted by 15.4% and 32%, respectively. The performance of the IMC-EH can be further improved by increasing the number of the endmost magnets. Experimental investigations reveal that the IMC-EH generates a maximum RMS output power density of 56.25 μW Oe−2 cm−3, surpassing existing magnetically coupled piezoelectric energy harvesters. Remarkably, even under an ambient magnetic field as low as 1 Oe, the proposed IMC-EH still yields a total output power of 185 μW, sufficient to continuously power 26 LEDs in real time. This demonstrates its potential as a promising solution for low-power consumption small electronics. Furthermore, the implications of this work extend beyond its immediate benefits, as it inspires the design of future self-powered wireless sensor networks in the context of the Internet of Things.

Електромагнітна небезпека електро- і гібридного транспорту

The purpose of the article is to determine the impact of electromagnetic radiation from electric vehicles. Hybrid and electric cars emit extremely low-frequency electromagnetic radiation (EMR) or magnetic fields. Studies of EMF levels emitted by cars show that they pose a threat to human health. Measurements of the magnetic induction of internal combustion engine cars, electric cars, and hybrid cars confirm that the magnetic field induction of an electric car is twice as high as that of an internal combustion engine car and does not depend on the speed of movement. The magnetic field induction of a hybrid car is greater than that of an electric car and tends to depend on the speed of movement. The magnetic field induction during external charging of an electric vehicle in the cabin is much lower than when driving. The average value of magnetic field induction in the interior of an electric vehicle is 0.85 ± 0.18 μT; Coverage factor K = 2 at a confidence level of P = 0.95. The magnetic field induction of an electric vehicle is twice as high as that of a car with an internal combustion engine and does not depend on the speed of movement. The average value of magnetic field induction in the interior of a hybrid car is 1.28 ± 0.61 μT; Coverage factor K = 2 at a confidence level of P=0.95. The magnetic field induction of a hybrid car is higher than that of an electric car and tends to depend on the speed of movement.The conducted studies show that electrical equipment in electric vehicles and, in particular, in an electric car and a hybrid car is a source of alternating EMF with strong temporal and spatial heterogeneity in the frequency range from 0 to hundreds of megahertz. This is due to the fact that the MF in an electric vehicle and a hybrid car is a superposition of fields from many sources. The direct sources of MF in electric vehicles are traction motors, rechargeable traction batteries, current-carrying elements, various electrical equipment, such as starting and braking resistance, group switches, rheostat units, electrical circuits for ventilation, lighting, heating, etc. Electronic devices on board are usually higher-frequency than MFs due to changes in the driving mode of electric and hybrid vehicles.

Low-Frequency Dynamic Magnetic Fields Decrease Cellular Uptake of Magnetic Nanoparticles

Magnetic nanoparticles have gained attention as a potential structure for therapy and diagnosing oncological diseases. The key property of the magnetic nanoparticles is the ability to respond to an external magnetic field. It is known that magnetofection causes an increase in the cellular uptake of RNA and DNA in complexes with magnetic nanoparticles in the presence of a permanent magnetic field. However, the influence of a dynamic magnetic field on the internalization of MNPs is not clear. In this work, we propose the idea that applying external low-frequency dynamic magnetic fields may decrease the cellular uptake, such as macrophages and malignant neuroblastoma. Using fluorescence microscopy and atomic emission spectroscopy, we found that oscillating magnetic fields decreased the cellular uptake of magnetic nanoparticles compared to untreated cells by up to 46%. In SH-SY5Y tumor cells and macrophage RAW264.7 cells, the absolute values of Fe per cell differed by 0.10 pg/cell and 0.33 pg/cell between treated and untreated cells, respectively. These results can be applied in the control of the cellular uptake in different areas of biomedicine.

Magnetoactive Composite Conduits Based on Poly(3-hydroxybutyrate) and Magnetite Nanoparticles for Repair of Peripheral Nerve Injury.

Peripheral nerve injury poses a threat to the mobility and sensitivity of a nerve, thereby leading to permanent function loss due to the low regenerative capacity of mature neurons. To date, the most widely clinically applied approach to bridging nerve injuries is autologous nerve grafting, which faces challenges such as donor site morbidity, donor shortages, and the necessity of a second surgery. An effective therapeutic strategy is urgently needed worldwide to overcome the current limitations. Herein, a magnetic nerve guidance conduit (NGC) based on biocompatible biodegradable poly(3-hydroxybutyrate) (PHB) and 8 wt % of magnetite nanoparticles modified by citric acid (Fe3O4-CA) was fabricated by electrospinning. The crystalline structure of NGCs was studied by X-ray diffraction, which indicated an enlarged β-phase of PHB in the composite conduit compared to a pure PHB conduit. Tensile tests revealed greater ductility of PHB/Fe3O4-CA: the composite conduit has Young's modulus of 221 ± 52 MPa and an elongation at break of 28.6 ± 2.9%, comparable to clinical materials. Saturation magnetization (σs) of Fe3O4-CA and PHB/Fe3O4-CA is 61.88 ± 0.29 and 7.44 ± 0.07 emu/g, respectively. The water contact angle of the PHB/Fe3O4-CA conduit is lower as compared to pure PHB, while surface free energy (σ) is significantly higher, which was attributed to higher surface roughness and an amorphous phase as well as possible PHB/Fe3O4-CA interface interactions. In vitro, the conduits supported the proliferation of rat mesenchymal stem cells (rMSCs) and SH-SY5Y cells in a low-frequency magnetic field (0.67 Hz, 68 mT). In vivo, the conduits were used to bridge damaged sciatic nerves in rats; pure PHB and composite PHB/Fe3O4-CA conduits did not cause acute inflammation and performed a barrier function, which promotes nerve regeneration. Thus, these conduits are promising as implants for the regeneration of peripheral nerves.

Enhancement of Lycopene Synthesis via Low-Frequency Alternating Magnetic Field in Brassica trispora

In recent years, magnetic fields have emerged as a non-thermophysical treatment with a significant impact on microbial fermentation processes. Brassica trispora is a microorganism known for its industrial-scale production of lycopene and high yield of single cells. This study aimed to investigate the impact of low-frequency magnetic fields on lycopene synthesis by Brassica trispora and elucidate the underlying mechanism for enhancing lycopene yield. The results indicate that both the intensity and duration of the magnetic field treatment influenced the cells. Exposing the cells to a 0.5 mT magnetic field for 48 h on the second day of fermentation resulted in a lycopene yield of 25.36 mg/g, representing a remarkable increase of 244.6% compared to the control group. Transcriptome analysis revealed that the alternating magnetic field significantly upregulated genes related to ROS and the cell membrane structure, leading to a substantial increase in lycopene production. Scanning electron microscopy revealed that the magnetic field treatment resulted in a rough, loose, and wrinkled surface morphology of the mycelium, along with a few micropores, thereby altering the cell membrane permeability to some extent. Moreover, there was a significant increase in intracellular ROS content, cell membrane permeability, key enzyme activity involved in lycopene metabolism, and ROS-related enzyme activity. In conclusion, the alternating frequency magnetic field can activate a self-protective mechanism that enhances lycopene synthesis by modulating intracellular ROS content and the cell membrane structure. These findings not only deepen our understanding of the impact of magnetic fields on microbial growth and metabolism but also provide valuable insights for developing innovative approaches to enhance carotenoid fermentation.

Enhancement of magnetoelectric coupling in laminate composites of textured Fe–Ga thin sheet and PZT

Magneto-mechano-electric (MME) generators consisting of piezoelectric and magnetostrictive materials can convert the stray magnetic noise to useful electric energy for the wireless sensor networks utilizing the magnetoelectric coupling effect and magnetic interactions. In this paper, a scalable engineering approach was proposed to fabricate the laminate MME generator composed of a PZT/Fe–Ga/PZT sandwich structure. The Goss-oriented Fe81Ga19 thin sheet with a large magnetostriction of 244 ppm was produced by a simple and low-cost approach, and the commercial polycrystalline piezoelectric ceramic products (PZT-5H) were used as the PZT layers. The effect of grain orientation, device structure, magnetic field amplitude, and resonance frequency on the electrical output of the PZT/Fe–Ga/PZT MME generator was investigated. The electrical output of the MME generator containing the Goss-oriented Fe81Ga19 thin sheet reached an AC voltage of 4.58 V and the ME coefficient of 76.33 V/cm·Oe under a low excitation magnetic field of 26 Oe at a low resonance frequency of 26 Hz. The MME generator with a Goss-oriented Fe–Ga layer shows 4.7 times higher output voltage and ME coupling coefficient than that with the no-oriented polycrystalline Fe–Ga layer, but only 81% of the latter’s resonance frequency. This is related to the significant increase in magnetostriction due to the texture transition after secondary recrystallization annealing at the temperature of 950 °C. This paper provides a very promising solution to meet the self-power supply needs of the Internet of Things utilizing low-value and low-frequency magnetic fields.

Assessment of extremely low frequency electric and magnetic field of 400kV transmission lines and substations in Oman

The present study is centered on the investigation of longitudinal and lateral profiles of Extremely low-frequency Electromagnetic field experiments conducted at three distinct locations in Oman. The investigation encompasses findings obtained from 400kV transmission lines and substations. The analysis of electric and magnetic fields emitted by transmission lines was conducted using an EHP-50F E&amp;H field analyzer sensor set and an environmental meter. The measurements were conducted at 400kV transmission lines or to a distance of the insignificant field at the high-voltage substation, various components such as power transformers, CT (current transformers), PT (potential transformers), circuit breakers, reactors, earth switches, transport couplers, lightning arrestors, and other. This research in Oman marks the initial exploration of various factors pertaining to the Oman Electricity Transmission Company (OETC) and its technical standards, which are founded on optimal practices. These factors encompass the interphase spacing, the spacing between conductors within a bundle of twin conductors, the configuration of phases on a tower, the crosssectional area of conductors, and similar considerations. The proposed study aims to support the Sultanate of Oman's objective of establishing a high-quality smart transmission grid by 2030. This system will facilitate the efficient, reliable, and secure transfer and distribution of power, while also offering economic benefits. This research aims to cater to the needs of students and engineers by offering a highly practical approach that utilizes appropriate equipment. This article presents a systematic approach to the implementation of a smart transmission grid, incorporating the aforementioned attributes.

3D Position Tracking using On-chip Magnetic Sensing in Image-guided Navigation Bronchoscopy.

This paper presents a compact and low-cost on-chip sensor and readout circuit. The sensor achieves high-resolution 5-degrees-of-freedom (DoF) tracking (x, y, z, yaw, and pitch). With the help of an external wire wound sensor, it can also achieve high-resolution 6-degrees-of-freedom (DoF) tracking (x, y, z, yaw, pitch, and roll angles). The sensor uses low-frequency magnetic fields to detect the position and orientation of instruments, providing a viable alternative to using X-rays in image-guided surgery. To measure the local magnetic field, a highly miniaturised on-chip magnetic sensor capable of sensing the magnetic field has been developed incorporating an on-chip magnetic sensor coil, analog-front end, continuous-time ΔΣ analog-to-digital converter (ADC), LVDS transmitter, bandgap reference, and voltage regulator. The microchip is fabricated using 65 nm CMOS technology and occupies an area of 1.06 mm2, the smallest reported among similar designs to the best of our knowledge. The 5-DoF system accurately navigates with a precision of 1.1 mm within the volume-of-intrest (VOI) of 15×15×15 cm3. The 6-DoF system achieves a navigation accuracy of 0.8 mm and an angular error of 1.1 degrees in the same VOI. These results were obtained at a 20 Hz update rate in benchtop characterisation. The prototype sensor demonstrates accurate position tracking in real-life pre-clinical in-vivo settings within the porcine lung of a live swine, achieving a reported worst-case registration accuracy of 5.8 mm.

Response of photosynthesis and electrical reactions of wheat plants upon the action of magnetic fields in the Schumann resonance frequency band

ABSTRACT Alternating magnetic fields (MF) with Schumann resonance frequencies accompanied the development of living organisms throughout evolution, but today it remains unclear whether they can have a special biological effect in comparison with surrounding non-resonant frequencies. This work shows some stimulating effect of extremely low-frequency MFs on morphometric parameters and the activity of physiological processes in wheat (Triticum aestivum L.). It is shown that the MF effect is more pronounced for transient processes – photosynthesis reactions and changes in electrical potential caused by turning on light. For light-induced electrical reactions, the dependence of the severity of the effect on the frequency of the applied MF was demonstrated. It is shown that the most pronounced effect occurs in the 14.3 Hz field, which corresponds to the second harmonic of the Schumann resonance. The predominant sensitivity of signal-regulatory systems gives reason to assume the influence of MFs with Schumann resonance frequencies on the interaction of plants with environmental factors under conditions of a changed electromagnetic environment. Such conditions can occur, for example, with an increase in lightning activity caused by climate change, which serves as the basis for the generation of Schumann resonances, and with the development of artificial ecosystems outside the Earth’s atmosphere.