EM Exposure Research Articles

Electromagnetic Assessment of UHF-RFID Devices in Healthcare Environment

In this work, the evaluation of electromagnetic effect of Ultra High Frequency Radio Frequency Identification (UHF-RFID) passive tags used in the healthcare environment is presented. In order to evaluate exposure levels caused by EM field (865–868 MHz) of UHF-RFID readers, EM measurements in an anechoic chamber and in a real medical environment (Hospital Universitario de Canarias), as well as simulations by 3D Ray Launching algorithm, and of biophysical exposure effects in human models are presented. The results obtained show that the EM exposure is localized, in close vicinity of RFID reader and inversely proportional to its reading range. The EM exposure levels detected are sufficient to cause EM immunity effects in electronic devices (malfunctions in medical equipment or implants). Moreover, more than negligible direct effects in humans (exceeding relevant SAR values) were found only next to the reader, up to approximately 30% of the reading range. As a consequence, the EM risk could be firstly evaluated based on RFID parameters, but should include an in situ exposure assessment. It requires attention and additional studies, as increased applications of monitoring systems are observed in the healthcare sector—specifically when any system is located close to the workplace that is permanently occupied.

An Ecological Model of Risk Factors in Older Adults With Repeated Exposure to Elder Mistreatment

Limited empirical studies examined the factors related to repeated EM exposures among Chinese older immigrants. Guided by the ecological model, this study aims to explore what are the risk factors leading to recurrence of EM. Data were drawn from the two-wave PINE Study with 725 participants having EM at baseline and 191 reported repeated EM after two years. EM was evaluated by a 66-item instrument, including psychological, physical, and sexual mistreatment, financial exploitation, and caregiver neglect. Logistic regression was used. Increasing financial independence was associated with lower possibility of repeated EM (OR: 0.72, 95%CI 0.56-0.92). Every one unit increase in ADL impairment (OR: 1.10, 95%CI 1.02-1.18), IADL impairment (OR: 1.09, 95%CI 1.05-1.13) and increase frequency of alcohol consumption (OR: 1.33, 95%CI 1.06-1.66) were associated with higher possibility of repeated EM. Social service could improve physical function, provide financial support, and reduce health-risk behavior to prevent the recurrence of EM.

PSX-B-1 Effect of exposure time and dose of effective microorganisms (EM®) on feed in vitro rumen fermentation and digestibility

Abstract The objective was to evaluate the effect of feed inoculation with effective microorganisms (EM®) (mainly containing Lactobacillus spp.,Rhodopseudomona palustrisand Saccharomyces cerevisiae) on rumen fermentation using in vitrogas production technique. We hypothesized that increasing doses and allowing exposure of EM® for up to 48 hours, would improve digestibility and rumen fermentation. The experimental design was a 4×4 completely randomized block design including 4 EM® levels [(0(EM0), 0.5(EM0.5), 1.0 (EM1) and 1.5 (EM1.5) mL EM® / kg DM] and 4 preincubation times [0 (T0), 12(T12), 24(T24), 48 (T48) h], with four repetitions per treatment. Treatments were evaluated using 100ml glass bottles with 0.5g of the diet (20% corn stover, 20% oat hay, 48.8% ground corn, 7% molasses, 1.2% urea, 1% soybean meal, 0.9% mineral premix,1.1% salt, dry matter basis) incubated with sheep ruminal fluid in 3 different occasions. Data were analyzed with PROC MIXED of SAS and orthogonal contrasts to determine the linear and quadratic effects of EM dose and exposure time. Interaction (P < 0.05) of EM x T was observed for in vitrodry matter digestibility (IVDMD), maximum gas volume (Vmax), total volatile fatty acids (VFA), acetate (ACE), propionate (PROP), butyrate (BUT) and ammonia-nitrogen (NH3), IVDMD was higher (P < 0.01, 4.8 and 3.72%) for T48EM1.5 than T12EM0 and T0EM0, PROP was higher (P < 0.05) for T48EM0, T48EM1 and 1.5 than T12EM0. The ACE:PROP ratio was higher (P < 0.05, 17.2%) for T12EM0 than T48EM1.5. IVDMD, PROP and NH3 linearly increased (P < 0.01) with increasing exposure time. EM levels have a quadratic effect (P < 0.01) with maximum response at EM0.5. It was concluded that the addition of 0.5 to 1.5 mL/kg DM of EM® to a sheep diet and increasing preincubation time, up to 48h, improve feed fermentation and digestibility.Project was supported by UNAM, DGAPA, PAPIIT (IT202120).

Methodology for determining the threshold distance for estimating the main EM exposure contribution in WLAN

The location of radiation sources in wireless networks is a key factor to characterize their contribution to electromagnetic exposure levels in order to deploy future networks that account for minimizing electromagnetic field levels. In relation to wireless local area networks, considering that mobile communication devices comply with the SAR (Specific Absorption Rate) limits imposed by the international standardization organizations for preserving human health, the interest is nowadays focused on the signal levels coming from the WiFi access points. This paper presents a methodology to determine the threshold distance at which the field strength levels from the AP are negligible in comparison with the radiation generated by a user equipment. The theoretical concepts, which can be applied to other technologies, were implemented by means of simulations and experimental measurements. For the simulations, actual WiFi antennas were modelled. Experimental measurements completed the results obtained in simulations, resulting in a greater number of real situations. Results showed that the threshold distance depends on the WiFi standard employed by the devices connected to the network.

Antibacterial Synergism of Electrospun Nanofiber Mats Functioned with Silver Nanoparticles and Pulsed Electromagnetic Waves.

The over-reliance on antibiotics and their enormous misuse has led to warnings of a future without effective medicines and so, the need for alternatives to antibiotics has become a must. Non-traditional antibacterial treatment was performed by using an aray of nanocomposites synergised with exposure to electromagnetic waves. In this manuscript, electrospun poly(vinyl alcohol) (PVA) nanofiber mats embedded with silver nanoparticles (Ag NPs) were synthesized. The nanocomposites were characterized by Transmission Electron Microscope (TEM), Scanning Electron Microscope (SEM), Current-Voltage (I-V) curves, and Thermogravimetric analysis (TGA) along with analysis of antibacterial impact against E. coli and S. aureus bacteria, studied by bacterial growing analysis, growth kinetics, and cellular cytotoxicity. The results indicated a spherical grain shape of silver of average size 20 nm and nanofibers’ mean diameter of less than 100 nm. The nanocomposite mats showed good exposure to bacteria and the ability to sustain release of silver for a relatively long time. Moreover, the applied electromagnetic waves (EMWs) were shown to be a synergistic co-factor in killing bacteria even at low concentrations of Ag NPs. This caused pronounced alterations of the bacterial preserved packing of the cell membrane. Thereby, the treatment with nanocomposite mats under EM wave exposure elucidated maximum inhibition for both bacterial strains. It was concluded that the functioning of nanofiber with silver nanoparticles and exposure to electromagnetic waves improved the antibacterial impact compared to each one alone.

RESEARCH ON THE INFLUENCE OF HIGH-FREQUENCY, SUPER-HIGH-FREQUENCY ELECTROMAGNETIC AND THERMAL EFFECTS ON THE PROPERTIES OF YAREGSKAYA AND DEVONIAN PETROLEUM

Petroleum produced in different regions and fields differ significantly in quality. The organization of pipeline transport of petroleum streams of a various quality produced in different geographic regions, according to a system with a complex topological structure, is possible only when controlling the quality of petroleum in traffic flows, in particular, controlling such property of petroleum as viscosity. Petroleum viscosity has a decisive influence on the performance of pumping and power equipment. The characteristics of the main petroleum pipelines depend on content’s viscosity. By influencing petroleum viscosity, it is possible to change the results of hydraulic calculations of main petroleum pipelines and pumping and power equipment without changing the equipment themselves, therefore, the task of changing the rheological characteristics of the pumped petroleum is timely. In this work, for the first time, thermal, super-high-frequency electromagnetic (SHF EM), high-frequency electromagnetic (HF EM) methods of treating the Siberian Devonian commercial petroleum and commercial petroleum of the Timan-Pechora province — Yaregskaya are studied. Both petroleum were exposed to thermal, high-frequency and super-high-frequency electromagnetic treatment on unique laboratory benches assembled at the Bashkir State University. As a result of the carried out studies, it was discovered that electromagnetic treatment affects the rheological properties of these petroleum in the temperature range corresponding to the operating temperatures of main petroleum pipelines. The most effective was the EM HF method of exposure. The relaxation time of the rheological properties of Devonian and Yaregskaya petroleum after EM treatment is 5 days, which is substantial compared to the currently popular thermal heating. The results of preliminary heat treatment with subsequent cooling on the Devonian and Yarega petroleum showed less efficiency compared to the results of electromagnetic treatment. When temperatures reach 30 degrees Celsius and above, the effectiveness of thermal and EM methods of exposure for both petroleum is reduced to zero. Another problem that arises during the pipeline transport of Yaregskaya and Devonian petroleum is the formation of asphalt-resin-paraffin deposits (ARPD) on the inner walls of the pipeline, leading to the need for more frequent cleaning of the pipeline, higher energy consumption to ensure the specified productivity of the pipeline. EM processing has also become one of the methods for solving this problem. As a result of an experiment to determine the amount of deposits on the inner walls of petroleum pipelines without treatment and after EM exposure, it was revealed that HF EM treatment is a preventive method for combating ARPD for Yaregskaya and Devonian petroleum. For Yaregskaya petroleum treated with HF EM field, the ARPD value on the walls of the model pipeline was 6 times less than for untreated Yaregskaya petroleum. Thus, as a result of all the work carried out within the framework of the study, it was found that high-frequency and super-high-frequency electromagnetic processing methods are effective in the transport of Yaregskaya and Devonian petroleum, and, unlike the thermal method of exposure and the introduction of additives, they contribute to an increase in the productivity of petroleum pipelines by improving the rheological properties of petroleum for a significantly long period of time, as well as to a reduction in formation of ARPD on the inner walls.

Validation of the detection of elder abuse through emergency care technicians (DETECT) screening tool: a study protocol

IntroductionElder mistreatment (EM) is a high prevalence threat to the health and well-being of older adults in the USA. Medics are well-positioned to help with identification of older adults at...

Brain EM Exposure for Voice Calls of Mobile Phones in Wireless Communication Environment of Seoul, Korea

The aim of this paper is to present the measurement results of the transmitted (Tx) power levels of mobile phones in currently operating wireless communication networks in Seoul in 2015 and 2017 and the calculation results of the specific absorption rate (SAR) in the brain for voice calls while holding a mobile phone against the user’s ear when operating at the measured mean power level. The Tx power levels of mobile phones using Code Division Multiple Access (CDMA) 2000, Wide CDMA (WCDMA), and Long-Term Evolution (LTE) networks were compared for the three main mobile network operators in South Korea. The actual mean Tx power level was less than 0.5% of the maximum power for the CDMA2000 and WCDMA networks. In the LTE networks, however, an extremely wide gap in Tx power was observed between the operators; two of the operators showed a mean power of less than 0.1% of the maximum, whereas the other showed mean powers of the three bands within the range of 0.8%–20% of the maximum power. The measurement results suggest that the SAR in the user’s brain is strongly dependent on the year the phone was used, the user-subscribed mobile operator, and the proportion of time connected to the network/technology. The maximum 1-g peak spatial-average SAR (psSAR) level at the mean Tx power in an LTE network was 4.8 mW/kg (for a child head model). A maximum gap of 25 dB in the psSAR was observed between all networks considered.

Simplified Measurement on the Impact of Radiation by Mobiles

in fast growing world Mobile phone has become part of the human life. Specific Absorption is a measurement for the amount of Electromagnetic energy that has been absorbed by human tissue ,. Electromagnetic Radiation associated with Mobile Phones is always as an issue that has to be addressed for human safety, Particularly for children. More focus has been paid to induced SAR in the human head when exposed to EM Waves emitted from mobile Phone Antenna, but while using mobile phone the user gets exposed to a dangerous electromagnetic Radiations. ICNIRP Prescribed some guidelines for EM Exposure Level for Public. The Present paper is discuss the SAR Values of different Mobile Phones, Measured How much People are Aware of SAR Values are given as a survey. The study is compromised individuals that visited in the survey site .The awareness is assessed using structured questions and it was recorded to measure the awareness.

In vitro Experiments of Magnetic Field in Human Exposures of Intermediate Frequency

Electromagnetic safety standards are continually updated according to the latest and accumulating scientific pieces of evidence in cell studies, in order to confirm the exact impacts of Electromagnetic Field (EMF) on in-vitro cellular level. Various biological experiments, of both in-vivo and in-vitro, have been conducted for the investigation of the potential effects of EMF, however, these investigations are mostly focused either on the power frequency or microwave EM exposures aiming at the impact on osteocyte or cancer cells. This paper presents an investigation of the bio-electromagnetic impact of the cell viability to HT1080 and UR61 cells and the DNA integrity to the HT1080 cell, under an acute magnetic field of intermediate frequencies (IF) at 100 kHz. IF frequencies are commonly adopted in the wireless power transfer in E-vehicle applications in recent years; this study aims to provide the missing evidence of in-vitro experiments of Magnetic Field in Human Exposures of IF. The impact of the cell viability variation was investigated by MTT assay, while the DNA integrity was investigated by Comet assay. Three identical repeated experiments of prolonging exposure of 6-hours magnetic field of 21A/m, at 100 kHz were carried out for DNA fragmentation; results have indicated that exposure level which is the reference level for the general public of ICNIRP of 21A/m for HT1080, would barely cause any impact on DNA integrity. Three identical repeated experiments of prolonging exposure of 24-hours at the same level of exposure for cell viability investigation, results have indicated that there is a significant statistical difference of cell viability observed in both HT1080 and UR61 cells. The cell viability outcomes were concluded by t-test for a p-value of less than 0.05.

Mechanic stress generated by a time-varying electromagnetic field on bone surface.

Bone cells sense mechanical load, which is essential for bone growth and remodeling. In a fracture, this mechanism is compromised. Electromagnetic stimulation has been widely used to assist in bone healing, but the underlying mechanisms are largely unknown. A recent hypothesis suggests that electromagnetic stimulation could influence tissue biomechanics; however, a detailed quantitative understanding of EM-induced biomechanical changes in the bone is unavailable. This paper used a muscle/bone model to study the biomechanics of the bone under EM exposure. Due to the dielectric properties of the muscle/bone interface, a time-varying magnetic field can generate both compressing and shear stresses on the bone surface, where many mechanical sensing cells are available for cellular mechanotransduction. I calculated these stresses and found that the shear stress is significantly greater than the compressing stress. Detailed parametric analysis suggests that both the compressing and shear stresses are dependent on the geometrical and electrical properties of the muscle and the bone. These stresses are also functions of the orientation of the coil and the frequency of the magnetic field. It is speculated that the EM field could apply biomechanical influence to fractured bone, through the fine-tuning of the controllable field parameters. Graphical abstract Mechanic stress on bone surface in a time-varying magnetic field.

Reliable RF B/E-Field Probes for Time-Domain Monitoring of EM Exposure During Medical Device Testing

This paper presents electric and magnetic probes to measure radio frequency (RF) electric and magnetic fields for measuring the time-varying RF fields used in magnetic resonance imaging (MRI). A small single loop (2 cm) and short dipole antenna (2 cm) were developed to monitor the near field magnetic and electric exposure during the medical device testing. Theoretical analysis for each designed probe was performed to convert the real time receive signals to the exposed electric and magnetic field. Probes in this paper were tuned and matched at center frequency of 127.6 MHz for 3T MRI scanners to improve the accuracy and sensitivity. Different cables were designed to reduce the E-field pick up and achieving the most accurate measurement setup. Probes were fabricated on a single sided printed circuit board, FR4 of thickness 1.57 mm and a copper thickness of $35~\mu \text{m}$ . The measured S-parameters of the magnetic and electric field probes show less than −44 and −45 dB return loss at 127.6-MHz center frequency of the RF Birdcage.

Minimization of CYP2D6 Polymorphic Differences and Improved Bioavailability via Transdermal Administration: Latrepirdine Example.

Transdermal delivery has the potential to offer improved bioavailability by circumventing first-pass gut and hepatic metabolism. This study evaluated the pharmacokinetics of oral immediate release and transdermal latrepirdine in extensive and poor CYP2D6 metabolizers (EM/PM). Latrepirdine transdermal solution was prepared extemporaneously. The solution was applied with occlusive dressing to upper or middle back for 24h. Each subject received a single dose of 8.14mg oral, 5mg transdermal, and 10mg transdermal (EMs only) latrepirdine free base in a fixed sequence. Twelve EMs and 7 PMs (50-79years) enrolled and completed the study. Latrepirdine was well tolerated following both routes of administration. Dose-normalized latrepirdine total exposures were approximately 11-fold and 1.5-fold higher in EMs and PMs, respectively following administration of transdermal relative to oral. Differences between EM and PM latrepirdine exposures were decreased, with PMs having 1.9- and 2.7-fold higher peak and total exposures, respectively, following transdermal administration compared to 11- and 20-fold higher exposures, respectively, following oral administration. Transdermal delivery can potentially mitigate the large intersubject differences observed with compounds metabolized primarily by CYP2D6. Transdermal delivery was readily accomplished in the clinic using an extemporaneously prepared solution [NCT00990613].

Electromagnetic and Thermal Simulations of Human Neurons for SAR Applications.

The impact of the electromagnetic waves (EM) on human neurons (HN) has been under investigation for decades, in efforts to understand the impact of cell phones (radiation) on human health, or radiation absorption by HN for medical diagnosis and treatment. Research issues including the wave frequency, power intensity, reflections and scattering, and penetration depths are of important considerations to be incorporated into the research study. In this study, computer simulation for the EM exposure to HN was studied for the purpose of determining the upper limits of the electric and magnetic field intensities, power consumption, reflections and transmissions, and the change in temperature resulting from the power absorption by human neurons. Both high frequency structural simulators (HFSS) from ANSYS software, and COMSOL multi-physics were used for the simulation of the EM transmissions and reflections, and the temperature profile within the cells, respectively. For the temperature profile estimation, the study considers an electrical source of 0.5 watt input power, 64 MHz. The EM simulation was looking into the uniformity of the fields within the sample cells. The size of the waveguide was set to be appropriate for a small animal model to be conducted in the future. The incident power was fully transmitted throughout the waveguide, and less than 1% reflections were observed from the simulation. The minimum reflected power near the sample under investigation was found to be with negligible reflected field strengths. The temperature profile resulting from the COMSOL simulation was found to be near 0.25 m°K, indicating no change in temperature on the neuro cells under the EM exposure. The paper details the simulation results for the EM response determined by HFSS, and temperature profile simulated by COMSOL.

Evaluation of Electromagnetic Fields in Human Body Exposed to Wireless Inductive Charging System

This paper presents an evaluation of the EMFs in the human body exposed to the wireless inductive charging system of electric vehicles such that the compliance of this charging system with respect to human EM exposure limits can be examined. A magnetic resonance imaging-derived and high-resolution model of the human body is used. An exposure assessment of a representative wireless inductive charging system, under a limited set of operating conditions, is provided to estimate the induced EMFs. The numerical analysis is performed with the finite element method. Numerical modeling of the system next to a standing human model shows that the EM exposure limits can be absolutely satisfied even when the transmitter coil is very close to the body. Furthermore, the worst configuration for the exposure evaluation of the wireless charging system is taken into consideration. This paper provides a useful guideline for the industry to develop inductive charging systems following the safety standards of radiation protection.

Emerging Market Currency: The Common Risk Factor in Emerging Markets

In this note, we argue that the set of available EM investment options, both debt and equity, share a common risk factor that drives most of the EM-related risk and return. We demonstrate empirically that this common risk factor is best represented by EM currencies. This has an important implication for investors: while conventional wisdom argues against hedging currency exposure across the different EM investment choices based on the transaction costs involved in hedging such exposures, then the existence of a dominant common risk factor may be an argument for hedging to achieve diversification among different types of EM investments. We would argue that this should not be the case. Hedging EM currency exposure in any type of index leaves very little actual EM exposure in the investment. Rather, hedged EM equity indicies only provide (expensive) developed equity market exposure, while hedged EM fixed income exposure only provides (expensive) developed market fixed income exposure with, in both cases, little idiosyncratic EM risk. We would argue that embracing the common risk factor found in EM currencies is one of the strongest choices for investors seeking general “EM exposure” while simplifying market accessibility.

GSM Base Station Electromagnetic Radiation and Oxidative Stress in Rats

The ever increasing use of cellular phones and the increasing number of associated base stations are becoming a widespread source of nonionizing electromagnetic radiation. Some biological effects are likely to occur even at low-level EM fields. In this study, a gigahertz transverse electromagnetic (GTEM) cell was used as an exposure environment for plane wave conditions of far-field free space EM field propagation at the GSM base transceiver station (BTS) frequency of 945 MHz, and effects on oxidative stress in rats were investigated. When EM fields at a power density of 3.67 W/m2 (specific absorption rate = 11.3 mW/kg), which is well below current exposure limits, were applied, MDA (malondialdehyde) level was found to increase and GSH (reduced glutathione) concentration was found to decrease significantly (p < 0.0001). Additionally, there was a less significant (p = 0.0190) increase in SOD (superoxide dismutase) activity under EM exposure.

Alteration of Tight and Adherens Junctions on 50-Hz Magnetic Field Exposure in Madin Darby Canine Kidney (MDCK) Cells

Adherens (AJ) and tight junctions (TJ), as integrated parts of the junctional complex, are multifunctional specialized regions of the cell membrane in epithelial cells. They are responsible for cell-to-cell interactions and also have great importance in cellular signaling processes including Wnt protein-mediated signals. As electromagnetic field (EMF) exposure is known to cause alterations in the function as well as supramolecular organization of different cell contacts, our goal was to investigate the effect of 50-Hz magnetic field (MF) exposures on the subcellular distribution of some representative structural proteins (occludin, β-catenin, and cadherin) found in AJ and TJ. Additionally, cellular β-catenin content was also quantified by Western blot analysis. 50-Hz MF exposures seemed to increase the staining intensity (amount) of occludin, cadherins, and β-catenin in the junctional area of MDCK cells, while Western blot data indicated the quantity of b-catenin was found significantly decreased at both time points after EM exposures. Our results demonstrate that MF are able to modify the distribution of TJ and AJ structural proteins, tending to stabilize these cell contacts. The quantitative changes of β-catenin suggest a causative relationship between MF effects on the cell junctional complex and the Wnt signaling pathway.

Reduction of SAR in a human‐head model wrapped in clothing materials

AbstractAn analysis of clothing material for reducing RF energy absorption in a human‐head model has been studied using the finite‐difference time‐domain (FDTD) method. The local maximum specific absorption ratio (SAR) induced in the human head model is used for the evaluation of the clothing material's shielding effectiveness for EM exposure. It is found that clothing material with a dielectric constant close to that of human skin will induce higher RF energy absorption in the human‐head model. On the other hand, clothing material with a higher relative dielectric constant and permeability can greatly reduce RF energy absorption. If the clothing material is mixed with conducting materials or magnetic materials, a remarkable reduction of RF energy absorption in the human‐head model will be obtained. These preliminary results provide valuable knowledge to help in the manufacture of anti‐electromagnetic wave clothing. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 305–308, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10902

Electromagnetics - the uncertain health risks

Considering all the evidences to date in the scientific literature, an association between EM fields at the environmental levels and harmful effects to human is inconclusive or uncertain. However, the available evidences are enough to raise concern by certain segments of the public. In order to manage health risk in the face of scientific uncertainty, authorities may be persuaded to consider precautionary approaches while establishing safety standards and protection guidelines for EM fields. The precautionary principle is another management tool that could be adopted to deal with the health risks associated with EM exposure. It is an extremely conservative decision making principle that leads to prudent actions in the face of uncertainty. Where there is reasonable risk to the public, a prudent action to reduce the risk should be carried out. This procedure should hold even when the scientific proof is inconclusive as long, as the balance of quantitative and qualitative risk, benefit and cost of action justifies it.