Electromagnetic Field Devices Research Articles

Numerical modeling of electromagnetic field spatiotemporal evolution to evaluate the effects on calcium carbonate crystallization

Calcium carbonate (CaCO3) scaling is a significant impediment to water systems. Electromagnetic field (EMF) treatment is a promising approach to control scaling owing to its simplicity and low or no energy requirements. However, the underlying mechanisms by which EMF impacts CaCO3 crystallization remain unclear due to the challenges in measuring the EMFs in feed solutions and the lack of a fundamental understanding of the applied EMFs and the observed physicochemical phenomena. To fill this knowledge gap, a high-fidelity COMSOL model was first developed to simulate EMFs in bulk solutions for three alternating current-induced EMF devices with different configurations and properties. These were then integrated with experimental data to unveil the underlying mechanism by which applied EMFs alter the physicochemical processes. The study revealed that even low-strength EMFs (e.g., electric fields <0.15 V/m and magnetic fields <0.03 mT) promoted CaCO3 precipitation in bulk solutions. The electric fields created by these EMF devices resulted in higher Lorentz force compared to their induced magnetic fields. The methodology of this study offers the capability to predict the effectiveness of different EMF devices in facilitating crystallization processes, and these mechanistic insights lay the foundation for the smart design of EMF devices for diverse water treatment applications.

Development of Wearable Pulsed Electromagnetic Field Device and Its Application to Autonomic Nervous System Regulation

Development of Wearable Pulsed Electromagnetic Field Device and Its Application to Autonomic Nervous System Regulation

Alternating current electromagnetic field exposure lessens intramyocellular lipid accumulation due to high-fat feeding via enhanced lipid metabolism in mice.

Long-term high-fat feeding results in intramyocellular lipid accumulation, leading to insulin resistance. Intramyocellular lipid accumulation is related to an energy imbalance between excess fat intake and fatty acid consumption. Alternating current electromagnetic field exposure has been shown to enhance mitochondrial metabolism in the liver and sperm. Therefore, we hypothesized that alternating current electromagnetic field exposure would ameliorate high-fat diet-induced intramyocellular lipid accumulation via activation of fatty acid consumption. C57BL/6J mice were either fed a normal diet (ND), a normal diet and exposed to an alternating current electromagnetic field (ND+EMF), a high-fat diet (HFD), or a high-fat diet and exposed to an alternating current electromagnetic field (HFD+EMF). Electromagnetic field exposure was administered 8 hrs/day for 16 weeks using an alternating current electromagnetic field device (max.180 mT, Hokoen, Utatsu, Japan). Tibialis anterior muscles were collected for measurement of intramyocellular lipids, AMPK phosphorylation, FAT/CD-36, and carnitine palmitoyltransferase (CPT)-1b protein expression levels. Intramyocellular lipid levels were lower in the HFD + EMF than in the HFD group. The levels of AMPK phosphorylation, FAT/CD-36, and CPT-1b protein levels were higher in the HFD + EMF than in the HFD group. These results indicate that alternating current electromagnetic field exposure decreases intramyocellular lipid accumulation via increased fat consumption.

Magnetic Field‐Directed Deep Thermal Therapy via Double‐Layered Microneedle Patch for Promoting Tissue Regeneration in Infected Diabetic Skin Wounds

AbstractAlthough near‐infrared (NIR) light‐based photothermal therapies have shown therapeutic potential for infected wounds, the attenuation of NIR light intensity in tissue has severely limited the usage in deep bacterial infections. Herein, magneto‐thermal responsive bilayer microneedles (Fe‐Se‐HA MNs) consisting of functionalized hyaluronic acid (HA), ferro‐ferric oxide (Fe3O4), and micelle‐protected selenium nanoparticles (SeNPs@LAS) are constructed to overcome this challenge based on a self‐designed disk‐shaped electromagnetic field device (Disk‐ZVS). The electromagnetic field generated by the Disk‐ZVS shows virtually no intensity attenuation in living tissue. Finite element simulations showed that the field intensity and electromagnetic loss are concentrated on the tips of Fe‐Se‐HA MNs. The MNs are able to puncture hard scabs, penetrate into bacterial biofilms, and perform effective magnetic‐thermal conversion for deep hyperthermia sterilization. Following, the Fe‐Se‐HA MNs can be gradually degraded by excessive hyaluronidase in diabetic wound to release SeNPs, which reduce reactive oxygen species (ROS) to regulate wound redox homeostasis. Meanwhile, the SeNPs are beneficial to angiogenesis, which facilitates blood vessel formation and promotes wound repair. Therefore, various functions can be achieved for the Fe‐Se‐HA MNs, such as magneto‐thermal disinfection, deep and non‐invasive tissue penetration, anti‐inflammation, and pro‐angiogenesis, which shows great potential as an adjunctive therapy for infected diabetic wounds.

An Alternating, Current-Induced Electromagnetic Field for Membrane Fouling and Scaling Control during Desalination of Secondary Effluent from Municipal Wastewater

Membrane treatment of secondary effluent for reuse applications is a promising approach to expand water supplies and provide flexibility to water resources management. However, effective control of membrane fouling and scaling is crucial for cost-effective treatment and system resilience. This study compared the performance of antiscalants to an alternating, current-induced electromagnetic field (EMF) as an alternative pretreatment method to reverse osmosis. Compared to the no-EMF control experiments, the EMF device resulted in 13% higher water recovery and 366% lower flux decline at 60% of water recovery, along with 2–8 times lower precipitation of fouling and scaling, as evidenced by scanning electron microscope, energy dispersive X-ray spectroscopy, and chemical extraction analysis. The combination of the EMF with antiscalant was more effective for reducing membrane fouling and scaling, increasing water recoveries up to 89.3%, as compared to the EMF (67.5%) and antiscalant-only (73.6%) configurations. This is the first study to demonstrate synergistic effects of using an EMF in combination with antiscalants and could lead to lower pretreatment costs. Additional research is required to quantify the economics of this approach and to fully understand the fundamental mechanisms governing fouling and scaling control by an EMF.

Impact of Novel Pulsed Electromagnetic Field Device on Competitive Athlete Performance

Impact of Novel Pulsed Electromagnetic Field Device on Competitive Athlete Performance

Clinical responses of subcutaneous abdominal fat and rectus abdominis muscle thicknesses following treatment with a high-intensity focused electromagnetic field device

Clinical responses of subcutaneous abdominal fat and rectus abdominis muscle thicknesses following treatment with a high-intensity focused electromagnetic field device

Effects of focused continuous pulsed electromagnetic field therapy on early tendon-to-bone healing.

AimsRotator cuff (RC) tears are common musculoskeletal injuries which often require surgical intervention. Noninvasive pulsed electromagnetic field (PEMF) devices have been approved for treatment of long-bone fracture nonunions and as an adjunct to lumbar and cervical spine fusion surgery. This study aimed to assess the effect of continuous PEMF on postoperative RC healing in a rat RC repair model.MethodsA total of 30 Wistar rats underwent acute bilateral supraspinatus tear and repair. A miniaturized electromagnetic device (MED) was implanted at the right shoulder and generated focused PEMF therapy. The animals’ left shoulders served as controls. Biomechanical, histological, and bone properties were assessed at three and six weeks.ResultsExtension of the tendon from preload to the maximum load to failure was significantly better in the PEMF-treated shoulders at three weeks compared to controls (p = 0.038). The percentage strain was significantly higher in the PEMF group at both timepoints (p = 0.037). Collagen organization was significantly better (p = 0.034) as was tissue mineral density in the PEMF-treated group at three weeks (p = 0.028). Tendon immunohistochemistry revealed a prominent increase in type I collagen at the repair site at three weeks following continuous PEMF treatment compared with controls. None of the other tested parameters differed between the groups.ConclusionMED-generated PEMF may enhance early postoperative tendon-to-bone healing in an acute rat supraspinatus detachment and repair model. Superior biomechanical elasticity parameters together with better collagen organization suggest improved RC healing.Cite this article: Bone Joint Res 2021;10(5):298–306.

Effect of low frequency pulsed electromagnetic field on peak bone mass in young rats

To compare effects of low frequency pulsed electromagnetic fields on bone quality in growing rats between 1 h and 1.5 h. Thirty male SPF SD rats aged 4 weeks selected, which with the average body weight (115.8± 1.5) g, were divided into three groups according to random number table, 10 rats in each group. Control groups put rats into electromagnetic field device with 1.5 h every day, the other two groups put rats in electromagnetic field for 1 h and 1.5 h with a 50 Hz 0.6 mT intensity pulsed. The body weight of rats was weighed every 2 weeks and detected bone mineral density. Rats were sacrificed after 6 weeks to measure bone mineral density and biomechanical value of the right femur and lumbar vertebrae. Serum osteocalcin (OC) and tartrate-resistant acid phosphatase 5b (TRACP 5b) concentrations were determined by ELISA methods. After the magenta-picric acid staining, the micro tissue structure of the right tibia was observed, and the parameters of trabecular bone were analyzed by IPP 6.0 software. There were no statistical difference in body weight and organ coefficient among each groups at different times. Bone mineral density results showed that the body thickness of the 1.5 h group was significantly increased compared with control group at 6 weeks, and bone mineral density of femoral and vertebra in 1.5 h group were higher than that of in 1 h group. The results of three point femoral bending and vertebral compression test showed that the maximum load value of femur and vertebrae in 1.5 h group increased significantly compared with control group, and the maximum femoral load value in 1.5 h group was significantly higher than that of 1 h group, while there was no difference in elastic modulus values among each groups. Results of serum biochemical indicators showed that level of OC in 1.5 h group was significantly increased compared with control group, and significantly higher than that of 1 h group, while no significant difference in TRACP 5b values among each groups. Bone histomorphometry analysis results showed that there was no statistical difference in trabecular thickness, number and resolution between 1 h group and control group, trabecular bone thickness and number in 1.5 h group were increased, and trabecular bone resolution was decreased; The thickness and number of trabecular bone in 1.5 h group were also significantly increased compared with 1 h group, and the degree of resolution was reduced, and had significant difference between two groups. Intervention of 50 Hz 0.6 mT low frequency pulsed electromagnetic field for 1.5 h could effectively increase peak bone mineral density and bone microstructure in young rats, enhance biomechanical properties of bone, promote concentration of bone formation markers in rat blood. The results indicating that pulsed electromagnetic field could be used as a good way to prevent and treat osteoporosis.

Technological features of parts hardening in rotating electromagnetic field devices

The rotating electromagnetic field devices are presented and the physical effects that determine their application in hardening of the surface layer during processing by ferromagnetic indenters are disclosed. The results of experimental studies are presented that reveal the technological capabilities of magnetodynamic processing and the field of its practical application in the technology of manufacturing parts.

High Intensity Focused Electromagnetic Field Device for Urinary Incontinence

High Intensity Focused Electromagnetic Field Device for Urinary Incontinence

Safety and Efficacy of a Non-Invasive High-Intensity Focused Electromagnetic Field (HIFEM) Device for Treatment of Urinary Incontinence and Enhancement of Quality of Life.

Background and ObjectivesUrinary incontinence is a common and distressing condition which interferes with everyday life. Patients frequently experience discomfort related to urine leakage and the subsequent need to use absorbent pads. Since the continence mechanism is primarily maintained by a proper function of pelvic floor muscles (PFM), many treatment methods focused on strengthening of the PFM have been introduced in the past. The aim of this study was to evaluate the safety and efficacy of a high‐intensity focused electromagnetic technology (HIFEM) for treatment of urinary incontinence with emphasis on effects on prospective patients’ quality of life.Study Design/Materials and MethodsThe study followed an institutional review board approved protocol. A total of 75 women (55.45 ± 12.80 years, 1.85 ± 1.28 deliveries) who showed symptoms of stress, urge, or mixed urinary incontinence were enrolled. They received six HIFEM treatments (2 per week) in duration of 28 minutes. Outcomes were evaluated after the sixth treatment and at the 3‐month follow‐up. The primary outcome was to assess changes in urinary incontinence by the International Consultation on Incontinence Questionnaire‐Short Form (ICIQ‐SF) and changes in the number of absorbent pads used per day. The secondary outcome was subjective evaluation of the therapy and self‐reported changes in quality of life. The statistical analysis was conducted by paired T‐test and Pearson correlation coefficient ( α = 0.05).ResultsAfter the sixth session, 61 out of 75 patients (81.33%) reported significant reduction of their symptoms. The average improvement of 49.93% in ICIQ‐SF score was observed after the sixth treatment, which further increased to 64.42% at the follow‐up (both P < 0.001). Individually, the highest level of improvement was reached in patients suffering from mixed urinary incontinence (69.90%). The reduction of absorbent pads averaged 43.80% after the sixth treatment and 53.68% at 3 months (both P < 0.001), while almost 70% of patients (30 out of 43) reported decreased number of used pads. At the follow‐up, a highly significant medium correlation (r = 0.53, P < 0.001) was found between the ICIQ‐SF score improvement and the reduction in pad usage. A substantial decrease in the frequency of urine leakage triggers was documented. Patients reported no pain, downtime or adverse events, and also reported additional beneficial effects of the therapy such as increased sexual desire and better urination control.ConclusionsThis study demonstrated that HIFEM technology is able to safely and effectively treat a wide range of patients suffering from urinary incontinence. After six treatments, an improvement in ICIQ‐SF score and reduction in absorbent pads usage was observed. Based on subjective evaluation, these changes positively influenced quality of life. © 2019 The Authors. Lasers in Surgery and Medicine Published by Wiley Periodicals, Inc.

A Pilot Study of an Electromagnetic Field for Control of Reverse Osmosis Membrane Fouling and Scaling During Brackish Groundwater Desalination

This study investigated the effects of an electromagnetic field (EMF) on control of membrane fouling and scaling during desalination of brackish groundwater using a pilot reverse osmosis (RO) skid. The groundwater was primarily CaSO4 type with a total dissolved solids concentration of 5850 mg/L and hardness of 2500 mg/L as CaCO3. Two EMF devices were installed in the pipeline before a cartridge filter and in the RO feed inlet to induce an electric signal of ±150 kHz to the groundwater. The effects of EMF on membrane scaling were evaluated under accelerated conditions, i.e., without pH adjustment and addition of antiscalant. Two-phase experiments were conducted: Phase 1 (376 h) with the EMF devices turned on after 150 h baseline operation; and Phase 2 (753 h) with the EMF devices turned on from the beginning of testing. The EMF significantly reduced membrane scaling and improved RO performance by 38.3% and 14.3% in terms of normalized water permeability decline rate after 150 h and 370 h operation, respectively. Membrane autopsy results indicated that the fouling layer formed under the influence of EMF was loose with a low density and was easily removed by hydraulic flushing.

New Designing and using Electromagnetic Field Device for drawing bacterial growth map

In this study, electromagnetic field was used through a device made specifically for this purpose, and several types of bacteria were cultured in a separated manner using culture media used and incubated for 24 hours. With the exposure to the electromagnetic field from the device, the results showed that different bacteria grow in a different pattern, which demonstrate a different map of bacterial growth specific to each type of bacteria. This new technique is very important in the diagnosis of bacteria and determining their types through bacterial growth map after being effected by the electromagnetic field of the device. This finding opens a new field for research in order to discover other properties of the huge numbers of bacteria and to discover the fingerprint for every type of bacteria through this invention, which can make the diagnosis process of bacteria easier.

Assessment of an anti-scale low-frequency electromagnetic field device on drinking water biofilms

Low intensity and very low-frequency electromagnetic fields (EMF) used for preventing scaling in water distribution systems were tested for the first time for their potential impact on drinking water biofilms. The assays were carried out in laboratory-scale flow-through reactors that mimic water distribution systems. The drinking water biofilms were not directly exposed to the core of the EMF generator and only subjected to waterborne electromagnetic waves. The density and chlorine susceptibility of nascent or mature biofilms grown under exposure to EMF were evaluated in soft and hard water. This EMF treatment was able to modify CaCO3 crystallization but it did not significantly affect biofilms. Indeed, over all the tested conditions, there was no significant change in cell number, or in the integrity of the cells (membrane, culturability), and no measurable effect of chlorine on the biofilm.

A unipolar pulse electromagnetic field apparatus for magnetic therapy

The National Aeronautics and Space Administration (NASA) has spent years studying magnetic therapy and has built their own pulse electromagnetic field apparatus (PEMF). The concept of unipolar pulsed electromagnetic field (UPEMF) devices is presented; this device is an improved medical apparatus for magnetic therapy based on PEMF. A concentrator is designed to strengthen the magnetic field on the north pole and weaken the opposite field. The UPEMF device provides an approximate unipolar electromagnetic field and meets the medical requirements of magnetic therapy in terms of frequency, shape, and intensity.

Safety and efficacy of a novel high-intensity focused electromagnetic technology device for noninvasive abdominal body shaping.

Thermal fat reduction technologies are leading the market for nonsurgical abdominal contouring. However, they are ideal principally for patients with fat bulges. Our study investigates the effects of a novel nonthermal technology affecting the abdominal musculature and subcutaneous adipose tissue. A total of 22 patients (avg. BMI 23.8kgm-2 ) underwent 4 treatments on abdomen with high-intensity focused electromagnetic (HIFEM) field device. Treatments took 30minutes and were spaced apart by 2-3days. Photographs, weight, and waist measurements were taken at the baseline, after the last treatment, and at month 3 follow-up. Patient satisfaction was noted. Photographs were evaluated by blinded evaluators. The study protocol was completed by 19 patients. At month 3, the average waist size reduction was 4.37±2.63cm (P<0.01). The evaluators identified the before image from the 3-month image 89.47% of the time. About 91% of patients reported their abdominal appearance improved, and 92% stated they are satisfied with treatment results at month 3. No adverse events occurred. Observed waist size reduction and aesthetic improvement appear to be a combination of fat reduction and increased muscle definition of abdominal wall. In lower BMI patients, the increased abdominal muscle definition was largely responsible for the improvement. This novel energy device provides an additional tool for body contouring with primary application for lower and medium BMI patients.

Osteogenic Effect and Cell Signaling Activation of Extremely Low-Frequency Pulsed Electromagnetic Fields in Adipose-Derived Mesenchymal Stromal Cells.

Extremely low-frequency pulsed electromagnetic field (ELF-PEMF) devices have been used in the clinic for the treatment of bone disorders over the past 30 years. However, the underlying mechanism of which ELF-PEMFs exert an effect on tissues at a cellular level is not well understood. Hence, in this study, we explored the potential of different ELF-PEMF signals in modulating human adipose-derived mesenchymal stromal cells' (hAMSC) osteogenic capability. The cell proliferation rate was assessed using carboxyfluorescein succinimidyl ester (CFSE) method. The osteogenesis potential of cells was determined by alkaline phosphatase (ALP) activity, Alizarin-Red S staining, and RT-qPCR. Finally, the intracellular signaling pathway of a selected ELF-PEMF signal was examined using the PathScan Intracellular Signaling Array. Among the tested ELF-PEMF signals, program 20 (26 Hz) showed activation of the Akt and MAPK/ERK signaling cascade and significant upregulations of collagen I, alkaline phosphatase, and osteocalcin when compared to nonstimulated cells. This study demonstrates the potential of certain ELF-PEMF signal parameters to induce osteogenic differentiation of hAMSC and provides important clues in terms of the molecular mechanisms for the stimulation of osteogenic effects by ELF-PEMF on hAMSC.

Design, Fabrication and Validation of a Precursor Pulsed Electromagnetic Field Device for Bone Fracture Repair.

Pulsed electromagnetic field (PEMF) stimulation has been utilized in the medical field since the early 20th century. A number of therapeutic devices have been developed for the treatment of bone fractures and other medical applications. Most of these devices are backed by limited quantitative evidence. In this paper we present the development of a PEMF device for the purposes of determining, through in vitro experimentation, the exposure parameters required to give the most optimal fracture repair. Following electromagnetic field characterization, the device was shown to match well with computational field simulations. The exposure system has been validated through adipose-derived stem cell viability studies with an exposure frequency of 5 Hz and an intensity of 1.1 mT, for a duration of seven days at 30 minutes per day. Under the specific field characteristics chosen, the fatty-tissue derived stem cell proliferation was not hindered and in fact was stimulated $( 0. 025 < P < 0.01)$ by the PEMF exposure. With continued experimentation of numerous exposure conditions at the cellular scale, it will be possible to quantitatively determine the optimal exposure conditions required to produce the most rapid fresh fracture repair. Following this, there is significant potential for development of an optimized wearable device suitable for enhancing repair of all types of bone fractures.

Study on the effects of ionization seeds on pulse detonation characteristics

Ionization phenomenon is happened on the wave front due to the presence of high temperature and pressure in the detonation process. Plasma produced in the detonation process can be used as magnetohydrodynamic (MHD) generator or flow controlled by the external magnetic field. However, it is necessary to increase the ionization efficiency by adding metal ions with lower ionization potential owing to the limited amount of plasma produced by detonation. In this paper, a model of pulse detonation engine with ionization seeds was established. The Conservation Element and Solution Element (CE/SE) method was deduced to simulate the interaction between plasma and detonation process. The influence of ionization seed contents on the electrical conductivity and detonation characteristic parameters was analyzed, and the MHD control of detonation process was realized by adding the external electromagnetic field device. The results showed that it had a little influence on the detonation process but a great influence on the generation of detonation plasma by the addition of a certain amount of ionized seed. The ion mass fraction and electrical conductivity in the detonation tube were first increased and then decreased with the increase of ionization seed content, which reached the maximum at the ionization seed mass fraction of 0.05. The acceleration and deceleration process could be achieved by the MHD control.