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Abstract Background Chromium (Cr) and cobalt (Co) are the essential elements for producing metal implants, but might have potential health issues. The research on the correlation between metal implants and blood Cr and Co on a large population is still limited. Methods National Health and Nutrition Examination Survey (NHANES) is a program of studies designed to assess the health status of Americans began in the early 1960s. The study was based on the NHANES database from two data collection years (2015–2016 and 2017–2018). The exposure variable of this study was whether the participants had metal objects in the body or not. The outcome variables were blood concentrations of Cr and Co. Age, body mass index, sex, race/ethnicity, income to poverty ratio, tap water behavior, shellfish/fish/tuna/salmon eating habits, level of education, smoking behavior, marital status, blood hemoglobin, and data collection years were included as confounding variables. Results A total of 4412 participants, aged 40 years or older, were included in this analysis, consisting of the without metal objects group (n = 3150) and the metal objects group (n = 1262). Metal objects was positively correlated to the accumulation of blood Cr (β = 0.072, 95% CI: 0.043–0.102, p

• The expression for secondary fields produced by metal objects in AC magnetic field is derived. • A method to determine if eddy current interference exists based on phase shift is proposed. • A method of calibrating electromagnetic positioning system interfered by eddy currents is proposed. • Simulation experiments demonstrate the good calibration performance of the proposed method. Electromagnetic positioning technologies are frequently-used in surgical navigation systems to achieve precise position of surgical instruments in bodies. Still, in operating rooms with complex environments, they would be disturbed by eddy currents of metals. This paper explores a calibration method to mitigate eddy current interference. Initially, The study examined the generation mechanisms of eddy currents and established the expression of secondary magnetic fields they produced, which exhibited a 90-degree phase difference with the AC excitation field. Subsequently, an integral calibration method was proposed, leveraging fields' distinct phases for separating. Through simulation, various metal materials were modeled to study their impact on magnetic fields. The effectiveness of the calibration method was evaluated by comparing positioning accuracy before and after calibration. Results demonstrated over 80 % average calibration efficiency, effectively mitigating errors induced by metals and enhancing the system's reliability. This calibration method is crucial for the broader application of electromagnetic positioning systems. [ABSTRACT FROM AUTHOR]

Copyright of Arquivos de Ciências Veterinárias e Zoologia da Unipar is the property of Associacao Paranaense de Ensino e Cultura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Materiały Zachodniopomorskie: Annual Science Journal of National Museum in Szczecin is the property of Muzeum Narodowe w Szczecinie and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The wireless power transmission (WPT) system through magnetic field coupling for energy transmission may have foreign objects in the transmission channel in the practical application process, which brings hidden dangers to the WPT system. In this article, a WPT system without and with foreign objects is constructed. The influence of foreign objects on self-inductance and mutual-inductance of coupling coils is studied from the aspects of foreign object height, radius, transmission distance, and coil turns. Then, by constructing the circuit topology of the series structure, the influence of foreign objects on the transmission efficiency and the phase difference between voltage and current of the system is studied, and finally the influence law of metal foreign objects on the performance of the WPT system is summarized. [ABSTRACT FROM AUTHOR]

This article presents the feedback of two specialists in metal furniture - an archaeologist and a conservator-restorer - on the use of tomographic imaging in the analytical operating chain of artifacts, from the micro-sampling of samples to the various conservation-restoration interventions and their study of the objects. Different examples illustrate the advantages of this non-destructive analysis technique while considering its few limitations. As our activities are closely linked to the evolution of these new X-ray imaging technologies, we can already measure their impact both in the choice of intervention protocols during cleaning for study or restoration and in the scientific exploitation of the documentation and its valorization.

Wearable metal objects with high electromagnetic reflection characteristics can cause interference with the incident waves during exposure to the electromagnetic (EM) radiation. Therefore, it is of interest to investigate the effect of metal objects capable of increasing the absorption of EM energy and temperature within the tissues when get exposed to EM radiation. A numerical analysis of increase in specific absorption rate (SAR) and temperature distribution in a human head model when metal objects are placed between the head and radiating source is performed. A realistic three-dimensional heterogeneous human head model, metal objects of different shapes and sizes, and spectacles with different lenses are used. A half-wavelength dipole antenna operating at 1800 MHz served as an EM radiation source. Results show that the presence of metal objects in proximity to the head alters SAR and temperature increase within the tissues. In most cases, metal objects redistribute the EM field incident upon them to a smaller region increasing power absorption, thereby increasing SAR and temperature in that region. The power absorption in head layers is found to be sensitive to metal object's size and shape, and distance of the antenna from the objects.

Copyright of Adalya is the property of Koc University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

ABSTRACT In this article, a planar wideband microstrip patch antenna for ultrahigh frequency (UHF) radio identification (RFID) tag is presented. By incorporating two resonating C-shape patches, two resonances are excited close to each other to create wide impedance bandwidth to cover the entire operating frequency of UHF RFID system between 860 and 960 MHz for universal metal mountable tag. For complex impedance matching between the antenna input terminal and the referenced microchip whose impedance is Zchip = (31 − j212) Ω, a small rectangular loop feed structure was utilized where both of the resonating patches are magnetically coupled. The antenna design and simulation were carried out using finite element method based software, Ansoft HFSS v13. The simulated and measured radiation patterns at operating frequency of 915 MHz are in good agreement. The simulated and measured impedance bandwidth (Return Loss ≥ 3 dB) of 159 and 155 MHz were obtained that are well above the required 100 MHz bandwidth. © 2014 Wiley Periodicals, Inc. Microwave Opt Technol Lett 56:1579-1584, 2014 [ABSTRACT FROM AUTHOR]