Absorbable cyst brushes

Cytobrushes are used for low-invasive sample collection and screening in multiple diseases, with a significant impact on early detection, prevention, and diagnosis. This study focuses on improving the safety of cell brushing in hard-to-reach locations by exploring brush construction from absorbable materials. We investigated the efficacy of loop brushes made of absorbable suture wires of Chirlac, Chirasorb, Monocryl, PDS II, Vicryl Rapid, Glycolon, and Catgut during their operation in conjunction with fine-needle aspiration in an artificial cyst model. PDS II brushes demonstrated the highest efficiency, while Monocryl and Catgut also provided a significant brushing effect. Efficient brushes portrayed higher flexural rigidity than their counterparts, and their efficiency was inversely proportional to their plastic deformation by the needle. Our results open avenues for safer cell biopsies in hard-to-reach locations by utilizing brushes composed of absorbable materials.

Study on mechanical properties of corroded concrete columns strengthened with SMA wires

Ocean crossing bridges suffer from seawater corrosion all year round and their mechanical properties will be substantially diminished. In order to enhance the mechanical properties of reinforced concrete columns corroded by seawater, SMA wire is used to restrain the reinforced concrete columns corroded by seawater to study their mechanical properties. 14 specimens were produced through the test, and the natural seawater corrosion was simulated by preparing a certain concentration of synthetic seawater. The mechanical properties of SMA strengthened specimens and unreinforced specimens are compared and analyzed, including failure mode, hysteresis curve, bearing capacity, ductility, stiffness and energy dissipation; the effects of different synthetic seawater corrosion concentrations on the mechanical properties of reinforced concrete columns are discussed. The results show that the bearing capacity and stiffness of reinforced concrete columns subjected to synthetic seawater corrosion are substantially diminished than those of uncorroded specimens, and the bearing capacity of specimens decreases more with the increase of synthetic seawater corrosion concentration; synthetic seawater corrosion has obscure effect on the ductility and energy dissipation performance of the specimens. The mechanical properties of the corroded specimens strengthened with SMA wire have been substantially enhanced, particularly the energy dissipation performance and bearing capacity have been notably enhanced, and the ductility and stiffness have also been somewhat enhanced. At the same time, based on the test, the finite element model is created according to the test specimen, while the accuracy of the model is verified, and the effects of the spacing and diameter of SMA wire, the strength of concrete and the thickness of protective layer on the mechanical properties of the specimen are analyzed.

Single Wire Capacitive Wireless Power Transfer System for Wearable Biomedical Sensors Based on Flexible Graphene Film Material

This paper provides a special flexible graphene film based capacitive wireless power transfer (FGCPT) system for powering biomedical sensors of smart wearable devices. The graphene conductive material is flexible, transparent, highly conductive, and impermeable to most gases and liquids. Generally, the coupling structure of capacitive wireless power transfer (CPT) system is consisted of metal plates. However, it is hard to use for the biomedical sensors as the low power density and big volume. The shape of graphene conductive material could be easily built and changed according to the application requirements. In this paper, the power supply of biomedical sensing system could be accomplished by a single graphene film which is acted as the receiver of FGCPT system. The 200 mW power level is achieved with the maximum 9 V output voltage. The theory and calculation are verified by the simulated and experimental results.

Bioelectrocatalytic CO2 Reduction by Redox Polymer-Wired Carbon Monoxide Dehydrogenase Gas Diffusion Electrodes

The development of electrodes for efficient CO₂ reduction while forming valuable compounds is critical. The use of enzymes as catalysts provides the advantage of high catalytic activity in combination with highly selective transformations. We describe the electrical wiring of a carbon monoxide dehydrogenase II from Carboxydothermus hydrogenoformans (ChCODH II) using a cobaltocene-based low-potential redox polymer for the selective reduction of CO₂ to CO over gas diffusion electrodes. High catalytic current densities of up to -5.5 mA cm^-2 are achieved, exceeding the performance of previously reported bioelectrodes for CO₂ reduction based on either carbon monoxide dehydrogenases or formate dehydrogenases. The proposed bioelectrode reveals considerable stability with a half-life of more than 20 h of continuous operation. Product quantification using gas chromatography confirmed the selective transformation of CO₂ into CO without any parasitic co-reactions at the applied potentials.

Numerical study of aeolian vibration characteristics and fatigue life estimation of transmission conductors

The 2D computational fluid dynamics (CFD) model of transmission conductor is set up to simulate the aerodynamic forces varying with time on the conductor. Taking into account the geometrical nonlinearity of conductor lines, the finite element (FE) models of single span and two-span transmission lines discretized with beam elements are established. By means of the FE models, the aeolian vibrations of the conductor lines excited by the aerodynamic forces under different wind velocities are numerically simulated. The nonlinear resonant characteristics, the amplitude-frequency relations of the conductor lines during aeolian vibration are investigated, and the influences of the span length as well as the initial tension in conductors on the aeolian vibration characteristics are analyzed. Furthermore, a 3D FE model of a conductor segment and the suspension clamp is created to study the stress distributions of the 3D model corresponding to different lines during aeolian vibrations. Finally, based on the stress analysis of the 3D model, the fatigue lives of the transmission conductors during aeolian vibration under different wind velocities are estimated. The jump phenomenon induced by the nonlinear vibration is reflected by the numerical simulation considering the geometric nonlinearity, and it is found that the energy balance principle (EBP) overestimates the vibration amplitudes because it cannot take the influences of the geometrical nonlinearity and span length into account. The obtained results may provide some instructions for the prevention design of aeolian vibration.

Human reliability analysis in de-energization of power line using HEART in the context of Z-numbers

Investigation reveals that a high percentage of incident causes are ascribed to some forms of human error. To effectively prevent incidents from happening, Human Reliability Analysis (HRA), as a structured way to represent unintentional operator contribution to system reliability, is a critical issue. Human Error Reduction and Assessment Technique (HEART) as a famous HRA technique, provides a straightforward method to estimate probabilities of human error based on the analysis of tasks. However, it faces varying levels of uncertainty in assigning of weights to each error producing condition (EPC), denoted as assessed proportion of affect (APOA), by experts. To overcome this limitation and consider the confidence level (reliability or credibility) of the experts, the current study aimed at proposing a composite HEART methodology for human error probability (HEP) assessment, which integrates HEART and Z-numbers short for, Z-HEART. The applicability and effectiveness of the Z-HEART has been illustrated in the de-energization power line as a case study. Furthermore, a sensitivity analysis is fulfilled to investigate the validity of the proposed methodology. It can be concluded that Z-HEART is feasible for assessing human error, and despite the methodological contributions, it offers many advantages for electricity distribution companies.

Optically transparent vertical silicon nanowire arrays for live-cell imaging

Programmable nano-bio interfaces driven by tuneable vertically configured nanostructures have recently emerged as a powerful tool for cellular manipulations and interrogations. Such interfaces have strong potential for ground-breaking advances, particularly in cellular nanobiotechnology and mechanobiology. However, the opaque nature of many nanostructured surfaces makes non-destructive, live-cell characterization of cellular behavior on vertically aligned nanostructures challenging to observe. Here, a new nanofabrication route is proposed that enables harvesting of vertically aligned silicon (Si) nanowires and their subsequent transfer onto an optically transparent substrate, with high efficiency and without artefacts. We demonstrate the potential of this route for efficient live-cell phase contrast imaging and subsequent characterization of cells growing on vertically aligned Si nanowires. This approach provides the first opportunity to understand dynamic cellular responses to a cell-nanowire interface, and thus has the potential to inform the design of future nanoscale cellular manipulation technologies.

Why Wire Mattered: Building U.S. Networked Infrastructures, 1845-1910

Histories of technology, communications, or infrastructure typically draw few distinctions between the telegraph machine and its network. Yet that vast wired infrastructure not only made telegraph machines socially useful, it established a material foundation for telephone- and electrical-service networks. This article emphasizes American telegraph-network development and argues that the telegraph's needs catalyzed an electrical-wire supply industry with important continuities for later wired-network technologies. This study also shows that when telegraph networks emerged in the mid-1800s, industrial constraints meant the best wire available was still abjectly deficient for network needs. Wire vexed telegraph-line builders everywhere, but especially in the United States, where promoters favored less expensive but more vulnerable overhead lines. This article demonstrates that successfully networking the American nation involved decades of building and rebuilding, hundreds of mechanical inventions, hard-won industrial advances, and considerable individual sacrifice.

RF Heating Analysis of Implanted lead wires under 3.0 Tesla Magnetic Resonance Imaging System

RF heating has severely limited the application of high-field magnetic resonance imaging (MRI) in the patients with active implantable medical devices (AIMDs). Based on the finite element methods (FEMs), we study the RF heating of a lead implanted in the human body under 3.0 T MRI. The coupled simulation of electromagnetic and heat transfer is used to analyze the relationship between several factors, such as the resonance length, the implantation position, the implantation configuration, and the thermal conductivity, and RF heating. Results show that the resonance length of the lead is half of the RF wavelength, and the temperature rise exceeds the acceptable range of human body when the resonance occurs. The electromagnetic field distribution in the phantom is not uniform, so the field density around the wire may vary with different implantation positions and configurations. Temperature rise reduces with the decrease of the field density. In addition, RF heating can be reduced by increasing the thermal conductivity.

Discharge electrode geometry and energy efficiency in a one-stage wire-tube electrostatic precipitator operating at high concentrations of submicron liquid aerosol

In order to help answering the question 'Which electrode design is the best?', the precipitation performance of a tubular electrostatic precipitator was determined for different electrode designs with special attention to specific energy consumption. Experiments were conducted in a wire-tube arrangement with a high loading of liquid submicron particles causing strong space charge effects, also known as corona quenching. The experiments are supplemented by numerical simulation results showing the effect of residence time and power consumption on separation efficiency.

Electromagnetic compatibility issues in hybrid wired and wireless industrial networks

Industrial networks are currently the only communication means designed for real-time systems used in industry. Networked control systems (NCS) are still important and commonly used type of such systems operating on shop floor. As a computerized node of NCS, a programmable logic controller (PLC) is usually used. In most cases, contemporary devices of such kind are equipped with more than one network interface of various types. Typically, only one interface is activated in NCS. Sometimes, the other is used for communication between NCS and supervisory systems. Occasionally, it is additionally involved in the data transmission in the factory IT systems. In general, however, using a single network interface is a more common solution. In this paper, the mutual utilization of more than one interface is discussed in order to back up the NCS network and to manage the node-related traffic within the scope of higher level services. The question of dependability of such a system from the electromagnetic compatibility point of view is discussed. The example is provided based on Profinet via wired and wireless connection.

Current/Voltage Dual-Mode Single-Wire Simultaneous Bidirectional Interface Architecture for Sensor System

This paper presents a simultaneous bidirectional asymmetrical serial interface architecture for sensor systems. The proposed current/voltage dual-mode signaling scheme provides system synchronous clock and continuous data transmission between sensor integrated circuit (IC) and system-on-a-chip (SoC) using a single wire, which minimizes pin requirements on packages. Two types of transceiver circuits were implemented in a 65 nm CMOS technology for the sensor IC and the SoC, and they were designed for transmission rates of 1 Mb/s and 250 Kb/s, core areas of 0.008 mm² and 0.142 mm², and power consumptions of 7.1 μW and 145.8 μW, respectively. The transceiver circuit for the sensor IC was also applied to a monolithic PPG sensor implemented in 180 nm CMOS, and the acquisition and transmission of PPG sensor data with the transceiver for the SoC, implemented in 65 nm, was successfully achieved.

Dosimetric issues with simplified homogeneous body models in low frequency magnetic field exposure assessment

A simplified procedure, using circular disk models with homogeneous electric conductivity as representations for different body parts, has been proposed recently by product standard IEC 62822-3 for the assessment of magnetic field exposure in proximity to current-carrying conductors of welding equipment. Based on such simplified models, worst case coupling coefficients CCE_i(I), i.e. maximum induced electric field strength, normalised for current and frequency, for body parts at different distances d to straight single and double wire arrangements, as well as rectangular loop-shaped current paths are tabulated in the standard. In this work we compared CCE_i(I) values obtained by numerical computations with detailed anatomical models of the hand/forearm with the corresponding values given in IEC 62822-3 for current-carrying single wire conductors along the forearm at distances d = 30, 50 and 100 mm, respectively. Our results clearly indicated that the CCE_i(I) given in the standard may substantially underestimate the actual exposure. Using average values for tissue conductivities the observed extent of underestimation was up to 8.9 dB (factor 2.79) and may be even higher for worst case combinations of tissue conductivities. The reasons for this substantial underestimation are the oversimplified geometry, i.e. the circular disk does not reflect anatomical constrictions of the induction area present in realistic hand/forearm geometries, as well as the missing conductivity contrast between different tissues in the homogeneous disk models. Results of exposure assessment and corresponding minimum distances to components of welding equipment obtained by the simplified disk model approach suggested by IEC 62822-3 should therefore be considered with caution.

Evaluation of a proposed chair with an arm support for wiring terminal blocks on a vertical plane

To reduce the muscular exertion of an operator wiring terminal blocks on a vertical plane, a chair with a unique back that can be used as a back support or arm support is proposed in this study. A digital version of the chair was first developed based on anthropometric data and tested with a digital anthropometric subject using the Jack software before the physical chair was developed. To evaluate the effects of the physical chair, an experiment of wiring terminal blocks was conducted with 12 subjects to test whether the use of the arm support can reduce muscular exertion. The results showed that (1) exertion on the anterior deltoid, upper trapezium, and erector spinae muscles decreased with decrease in terminal block height; (2) using the arm support reduced exertion on the anterior deltoid and upper trapezium muscles; and (3) the subjects reported less self-perceived fatigue in the wrist, elbow, and shoulder regions when the arm support was used. These results confirm that the proposed chair can reduce muscular workload in the shoulder muscle over a proper range of working heights. However, using the arm support may restrict certain working postures and lead to force generation in upper extremity muscles.

Change in plant species composition on powerline corridor: a case study

Clear-cutting of powerline corridors (PLCs) adversely affects ecosystem function by fragmenting intact forests and supports biodiversity with the development of a structurally diverse vegetation. The study aimed to determine diversity and composition caused by clear-cutting and monitor change in species composition on the PLC passing through Research Forest of IUC Faculty of Forestry. Species composition was monitored in 10 permanent plots on the clear-cut area (over 3 years) paired on the forest edge (over 2 years) and forest interior (first year). Diversity, the cover of invasive plants, and life form traits of the sample plots were compared. Change in species composition with time was determined with redundancy analysis (RDA) for repeated measures using CANOCO 5. Open-site conditions caused by clear-cutting promoted the number of hemicryptophyte and therophyte life forms which resulted in a high species richness on the clear-cut area (167 species), followed by forest edge (117 species) and forest interior (60 species). However, species richness which showed a peak in the second year was decreased at the end of 3 years. Total cover of invasives was considerably higher on the clear-cut area (23%) compared with the forest (3.78%) and did not make a significant effect on forest interior species in narrow corridors. Clear-cutting combined with slash piling promoted the undesired vertical development of tree sprouts and Robinia pseudoacacia which shortened management rotation in a short period. However, sites dominated by shrubs such as Cistus creticus and Cistus salviifolius suppressed the development and invasion of undesirable trees.

Wireless induction coils embedded in diamond for power transfer in medical implants

Wireless power and data transfer to medical implants is a research area where improvements in current state-of-the-art technologies are needed owing to the continuing efforts for miniaturization. At present, lithographical patterning of evaporated metals is widely used for miniature coil fabrication. This method produces coils that are limited to low micron or nanometer thicknesses leading to high impedance values and thus limiting their potential quality. In the present work we describe a novel technique, whereby trenches were milled into a diamond substrate and filled with silver active braze alloy, enabling the manufacture of small, high cross-section, low impedance microcoils capable of transferring up to 10 mW of power up to a distance of 6 mm. As a substitute for a metallic braze line used for hermetic sealing, a continuous metal loop when placed parallel and close to the coil surface reduced power transfer efficiency by 43%, but not significantly, when placed perpendicular to the microcoil surface. Encapsulation of the coil by growth of a further layer of diamond reduced the quality factor by an average of 38%, which can be largely avoided by prior oxygen plasma treatment. Furthermore, an accelerated ageing test after encapsulation showed that these coils are long lasting. Our results thus collectively highlight the feasibility of fabricating a high-cross section, biocompatible and long lasting miniaturized microcoil that could be used in either a neural recording or neuromuscular stimulation device.

An experimental study on the thermal characteristics and heating effect of arc-fault from Cu core in residential electrical wiring fires

The characteristics of a series direct current (DC) arc-fault including both electrical and thermal parameters were investigated based on an arc-fault simulator to provide references for multi-parameter electrical fire detection method. Tests on arc fault behavior with three different initial circuit voltages, resistances and arc gaps were conducted, respectively. The influences of circuit conditions on arc dynamic image, voltage, current or power were interpreted. Also, the temperature rises of electrode surface and ambient air were studied. The results showed that, first, significant variations of arc structure and light emitting were observed under different conditions. A thin outer burning layer of vapor generated from electrodes with orange light was found due to the extremely high arc temperature. Second, with the increasing electrode gap in discharging, the arc power was shown to have a non monotonic relationship with arc length for constant initial circuit voltage and resistance. Finally, the temperature rises of electrode surface caused by heat transfer from arc were found to be not sensitive with increasing arc length due to special heat transfer mechanism. In addition, temperature of ambient air showed a large gradient in radial direction of arc.

Biological effects of exposure to static electric fields in humans and vertebrates: a systematic review

BACKGROUND

High-voltage direct current (HVDC) lines are the technology of choice for the transport of large amounts of energy over long distances. The operation of these lines produces static electric fields (EF), but the data reviewed in previous assessments were not sufficient to assess the need for any environmental limit. The aim of this systematic review was to update the current state of research and to evaluate biological effects of static EF.

METHODS

Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses) recommendations, we collected and evaluated experimental and epidemiological studies examining biological effects of exposure to static EF in humans (n = 8) and vertebrates (n = 40).

RESULTS

There is good evidence that humans and animals are able to perceive the presence of static EF at sufficiently high levels. Hair movements caused by electrostatic forces may play a major role in this perception. A large number of studies reported responses of animals (e.g., altered metabolic, immunologic or developmental parameters) to a broad range of static EF strengths as well, but these responses are likely secondary physiological responses to sensory stimulation. Furthermore, the quality of many of the studies reporting physiological responses is poor, which raises concerns about confounding.

CONCLUSION

The weight of the evidence from the literature reviewed did not indicate that static EF have adverse biological effects in humans or animals. The evidence strongly supported the role of superficial sensory stimulation of hair and skin as the basis for perception of the field, as well as reported indirect behavioral and physiological responses. Physical considerations also preclude any direct effect of static EF on internal physiology, and reports that some physiological processes are affected in minor ways may be explained by other factors. While this literature does not support a level of concern about biological effects of exposure to static EF, the conditions that affect thresholds for human detection and possible annoyance at suprathreshold levels should be investigated.

Effects of elevation change on mental stress in high-voltage transmission tower construction workers

High-voltage transmission tower construction is a high-risk operation due to the construction site locations, extreme climatic factors, elevated working surfaces, and narrow working space. To comprehensively enhance our understanding of the psychophysiological phenomena of workers in extremely high tower constructions, we carried out a series of field experiments to test and compare three working surface heights in terms of frequency-domain heart rate variability (HRV) measurements. Twelve experienced male workers participated in this experiment. The dependent variables, namely, heart rate (HR), normalized low-frequency power (nLF), normalized high-frequency power (nHF), and LF-to-HF power ratio (LF/HF), were measured with the Polar RS800CX heart rate monitor. The experimental results indicated that the task workload was similar between working surface heights. Tower construction workers perceived an increased level of mental stress as working surface height increased.

Effects of dietary green tea polyphenol supplementation on the health of workers exposed to high-voltage power lines

Although it has been several decades since the focus on the effect of extremely low frequency electromagnetic fields (ELF-EMF) of high-voltage power lines on human health, no consistent conclusion has been drawn. The present study aimed to investigate the change in oxidative stress after exposure to ELF-EMFs, and potential protective effects of green tea polyphenol supplementation (GTPS) on ELF-EMFs induced oxidative stress. A total of 867 subjects, including workers with or without exposure to ELF-EMFs of 110-420kV power lines, participated and were randomized into GTPS and placebo treatment groups. Oxidative stress and oxidative damage to DNA were assessed by urinary tests of 8-isoprostane and 8-OHdG. Significant increased urinary 8-isoprostane and 8-OHdG were observed in workers with ELF-EMFs exposure, which were diminished after 12 months of GTPS. No protective effects of GTPS on oxidative stress and oxidative damage to DNA were observed after three months of GTPS withdraw. We found a negative impact of high-voltage power lines on the health of workers. Long-term GTPS could be an efficient protection against the health issues induced by high-voltage power lines.

Electrical Wiring and Long-Distance Plant Communication

Electrical signalling over long distances is an efficient way of achieving cell-to-cell communication in living organisms. In plants, the phloem can be considered as a 'green cable' that allows the transmission of action potentials (APs) induced by stimuli such as wounding and cold. Measuring phloem potential changes and separating them from secondary responses of surrounding tissues can be achieved using living aphids as bioelectrodes. Two glutamate receptor-like genes (GLR3.3 and 3.6) were identified as being involved in the propagation of electrical activity from the damaged to undamaged leaves. However, phloem APs are initiated and propagated independently of these glutamate receptors. Here, we propose new screening approaches to obtain further information on the components required for electrical signalling in phloem cables.

Charging of the penis: an unusual method for sexual gratification

The presence of a foreign object in the bladder or urethra may cause a serious problem to the patient. Most of the cases are self-inserted as a result of sexual gratification. Here, we present a rare case of self introduction of the wire of a mobile charger within the bladder and urethra for sexual gratification. This case has yet to be reported in any previous work.

Co-recycling of acrylonitrile-butadiene-styrene waste plastic and nonmetal particles from waste printed circuit boards to manufacture reproduction composites

This study investigated the feasibility of using acrylonitrile-butadiene-styrene (ABS) waste plastic and nonmetal particles from waste printed circuit boards (WPCB) to manufacture reproduction composites (RC), with the aim of co-recycling these two waste resources. The composites were prepared in a twin-crew extruder and investigated by means of mechanical testing, in situ flexural observation, thermogravimatric analysis, and dimensional stability evaluation. The results showed that the presence of nonmetal particles significantly improved the mechanical properties and the physical performance of the RC. A loading of 30 wt% nonmetal particles could achieve a flexural strength of 72.6 MPa, a flexural modulus of 3.57 GPa, and an impact strength of 15.5 kJ/m2. Moreover, it was found that the application of maleic anhydride-grafted ABS as compatilizer could effectively promote the interfacial adhesion between the ABS plastic and the nonmetal particles. This research provides a novel method to reuse waste ABS and WPCB nonmetals for manufacturing high value-added product, which represents a promising way for waste recycling and resolving the environmental problem.

Towards plant wires

In experimental laboratory studies we evaluate a possibility of making electrical wires from living plants. In scoping experiments we use lettuce seedlings as a prototype model of a plant wire. We approximate an electrical potential transfer function by applying direct current voltage to the lettuce seedlings and recording output voltage. We analyse oscillation frequencies of the output potential and assess noise immunity of the plant wires. Our findings will be used in future designs of self-growing wetware circuits and devices, and integration of plant-based electronic components into future and emergent bio-hybrid systems.

Refining estimates of bird collision and electrocution mortality at power lines in the United States

Collisions and electrocutions at power lines are thought to kill large numbers of birds in the United States annually. However, existing estimates of mortality are either speculative (for electrocution) or based on extrapolation of results from one study to all U.S. power lines (for collision). Because national-scale estimates of mortality and comparisons among threats are likely to be used for prioritizing policy and management strategies and for identifying major research needs, these estimates should be based on systematic and transparent assessment of rigorously collected data. We conducted a quantitative review that incorporated data from 14 studies meeting our inclusion criteria to estimate that between 12 and 64 million birds are killed each year at U.S. power lines, with between 8 and 57 million birds killed by collision and between 0.9 and 11.6 million birds killed by electrocution. Sensitivity analyses indicate that the majority of uncertainty in our estimates arises from variation in mortality rates across studies; this variation is due in part to the small sample of rigorously conducted studies that can be used to estimate mortality. Little information is available to quantify species-specific vulnerability to mortality at power lines; the available literature over-represents particular bird groups and habitats, and most studies only sample and present data for one or a few species. Furthermore, additional research is needed to clarify whether, to what degree, and in what regions populations of different bird species are affected by power line-related mortality. Nonetheless, our data-driven analysis suggests that the amount of bird mortality at U.S. power lines is substantial and that conservation management and policy is necessary to reduce this mortality.

Coulomb interaction effects on the Majorana states in quantum wires

The stability of the Majorana modes in the presence of a repulsive interaction is studied in the standard semiconductor wire-metallic superconductor configuration. The effects of short-range Coulomb interaction, which is incorporated using a purely repulsive δ-function to model the strong screening effect due to the presence of the superconductor, are determined within a Hartree-Fock approximation of the effective Bogoliubov-De Gennes Hamiltonian that describes the low-energy physics of the wire. Through a numerical diagonalization procedure we obtain interaction corrections to the single particle eigenstates and calculate the extended topological phase diagram in terms of the chemical potential and the Zeeman energy. We find that, for a fixed Zeeman energy, the interaction shifts the phase boundaries to a higher chemical potential, whereas for a fixed chemical potential this shift can occur either at lower or higher Zeeman energies. These effects can be interpreted as a renormalization of the g-factor due to the interaction. The minimum Zeeman energy needed to realize Majorana fermions decreases with the increasing strength of the Coulomb repulsion. Furthermore, we find that in wires with multi-band occupancy this effect can be enhanced by increasing the chemical potential, i.e. by occupying higher energy bands.

Stretchable optoelectronic circuits embedded in a polymer network

Stretchable optoelectronic circuits, incorporating chip-level LEDs and photodiodes in a silicone membrane, are demonstrated. Due to its highly miniaturized design and tissue-like mechanical properties, such an optical circuit can be conformally applied to the epidermis and be used for measurement of photoplethysmograms. This level of optical functionality in a stretchable substrate is potentially of great interest for personal health monitoring.

Comparison of electric field exposure measurement methods under power lines

The object of the study was to investigate extremely low frequency (ELF) electric field exposure measurement methods under power lines. The authors compared two different methods under power lines: in Method A, the sensor was placed on a tripod; and Method B required the measurer to hold the meter horizontally so that the distance from him/her was at least 1.5 m. The study includes 20 measurements in three places under 400 kV power lines. The authors used two commercial three-axis meters, EFA-3 and EFA-300. In statistical analyses, they did not find significant differences between Methods A and B. However, in the future, it is important to take into account that measurement methods can, in some cases, influence ELF electric field measurement results, and it is important to report the methods used so that it is possible to repeat the measurements.

Power line interference filtering on surface electromyography based on the stationary wavelet packet transform

Power line interference is one of the main problems in surface electromyogram signals (EMG) analysis. In this work, a new method based on the stationary wavelet packet transform is proposed to estimate and remove this kind of noise from EMG data records. The performance has been quantitatively evaluated with synthetic noisy signals, obtaining good results independently from the signal to noise ratio (SNR). For the analyzed cases, the obtained results show that the correlation coefficient is around 0.99, the energy respecting to the pure EMG signal is 98-104%, the SNR is between 16.64 and 20.40dB and the mean absolute error (MAE) is in the range of -69.02 and -65.31dB. It has been also applied on 18 real EMG signals, evaluating the percentage of energy respecting to the noisy signals. The proposed method adjusts the reduction level to the amplitude of each harmonic present in the analyzed noisy signals (synthetic and real), reducing the harmonics with no alteration of the desired signal.

Decomposition of two types of electric wires considering the effect of the metal in the production of pollutants

Combustion runs at 700 °C in a horizontal laboratory furnace were carried out on two different electric wires (PVC and halogen-free wire). Tests were performed in the presence and in the absence of the metal conductor of the wires. The analyses of the polycyclic aromatic hydrocarbons (PAHs), chlorobenzenes (CBzs), chlorophenols (CPhs), mono- to octa-chlorodibenzo-p-dioxin and dibenzofurans (PCDD/Fs), and dioxin-like PCBs are shown. Regarding semivolatile compounds, PAHs production decreases in the presence of metal, while a higher amount of chlorinated compounds are emitted. Respect to the PCDD/Fs, the PVC wire in the presence of metal presents the highest emission, with a much more emission of furans than dioxins. The maximum emission is with 2 or 3 chlorine atom PCDD/Fs. PCBs emission correlates with PCDD/F production and represents 3-4% of total toxicity, determined by using WHO2005 factors.

High performance carbon nanotube-Si core-shell wires with a rationally structured core for lithium ion battery anodes

Core-shell Si nanowires are very promising anode materials. Here, we synthesize vertically aligned carbon nanotubes (CNTs) with relatively large diameters and large inter-wire spacing as core wires and demonstrate a CNT-Si core-shell wire composite as a lithium ion battery (LIB) anode. Owing to the rationally engineered core structure, the composite shows good capacity retention and rate performance. The excellent performance is superior to most core-shell nanowires previously reported.

[Childhood leukaemia in a residential area with a high-voltage power line: approach according to the Dutch Community Health Services' guideline 'Cancer Clusters']

The new Dutch Community Health Services' (GGD) guideline titled 'Cancer Clusters' describes a phased plan for investigating reported cancer clusters. In each phase, attention is paid to both health and environmental issues and their possible links to one another. Throughout the entire cluster investigation, good risk communication is essential. In accordance with the new guideline, the Rotterdam-Rijnmond Public Health Services investigated the incidence of childhood leukaemia in a residential area as well as the data available on the high-voltage power line located there. More children in this residential area had been diagnosed with leukaemia than expected. However, the children had not been subjected to prolonged exposure to strong magnetic fields emitted from the high-voltage power line. With this type of cluster investigation, it is not possible to establish a causal relationship between childhood leukaemia and high-voltage power lines. However, the research did provide stakeholders insight into the health-and-environment situation and thereby, the opportunity to assess the situation appropriately and to act accordingly, if desired.

Occupational posture exposure among construction electricians

The aim of this study is to record, objectively describe and compare working postures of Brazilian and Norwegian construction electricians. Postures of the upper arms, head, and neck during work and breaks were quantified by means of inclinometry for a representative sample of 12 Brazilian and 12 Norwegian electricians in the construction industry during a full work-shift. Despite that differences were found between specific work-related factors, Brazilian and Norwegian workers revealed a high and very similar level and pattern of postures for all evaluated body regions, suggesting that results could be extrapolated to other electricians. Upper arm elevation was high and similar for both groups and head flexion and extension was pronounced compared to other occupations. Thus, extreme postures were identified for construction electricians in both countries, with similar exposure pattern also for defined tasks (planning, support and wiredraw), suggesting that this job is risky regardless organizational differences.

Assessment of ELF magnetic fields produced by independent power lines

In this paper, the problem of assessing the ELF (extremely low-frequency) magnetic fields produced, in a certain area characterised by the presence of more than one independent power line, is faced. The use of the incoherent summation of the single contributions, as an advantageous estimator of the total magnetic field, is proposed and justified by means of a heuristic procedure. This kind of approach can be seen as a useful and practical tool to be employed in environmental impact analysis and in assessing long-term human exposure to ELF magnetic fields.

Electrochemical properties of GaN nanowire electrodes--influence of doping and control by external bias

We report on the electrochemical characteristics of GaN nanowire (NW) ensembles grown by plasma-assisted molecular beam epitaxy on Si111 substrates and on the influence of Si and Mg doping. The NW electrochemical properties in terms of surface capacitance (C(S)), surface resistance (R(S)) are extracted from electrochemical impedance spectra. While Mg doping of GaN NWs does not cause a significant variation of these quantities, an increase of the Si concentration leads to an increase of C(S) and a simultaneous decrease of R(S), indicating the presence of charge carriers in the NWs. According to the extracted values for R(S) and C(S) the NWs are classified into resistive and conductive. For conductive NWs charge transfer to a ferricyanide redox couple in the electrolyte is demonstrated and the ensemble average of the flatband voltage was determined. Variation of the lateral surface potential due to application of an external bias via the electrolyte is demonstrated.

The effect of nanowire length and diameter on the properties of transparent, conducting nanowire films

This article describes how the dimensions of nanowires affect the transmittance and sheet resistance of a random nanowire network. Silver nanowires with independently controlled lengths and diameters were synthesized with a gram-scale polyol synthesis by controlling the reaction temperature and time. Characterization of films composed of nanowires of different lengths but the same diameter enabled the quantification of the effect of length on the conductance and transmittance of silver nanowire films. Finite-difference time-domain calculations were used to determine the effect of nanowire diameter, overlap, and hole size on the transmittance of a nanowire network. For individual nanowires with diameters greater than 50 nm, increasing diameter increases the electrical conductance to optical extinction ratio, but the opposite is true for nanowires with diameters less than this size. Calculations and experimental data show that for a random network of nanowires, decreasing nanowire diameter increases the number density of nanowires at a given transmittance, leading to improved connectivity and conductivity at high transmittance (>90%). This information will facilitate the design of transparent, conducting nanowire films for flexible displays, organic light emitting diodes and thin-film solar cells.

The monitoring results of electromagnetic radiation of 110-kV high-voltage lines in one urban location in Chongqing P.R. China

To understand electromagnetic radiation field strength and its influencing factors of certain 110-kV high-voltage lines in one urban area of Chongqing by measuring 110-kV high-voltage line's electromagnetic radiation level. According to the methodology as determined by the National Hygienic Standards, we selected certain adjacent residential buildings, high-voltage lines along a specific street and selected different distances around its vertical projection point as monitoring points. The levels of electromagnetic radiations were measured respectively. In this investigation within the frequency of 5-1,000 Hz both the electric field strength and magnetic field strength of each monitoring sites were lower than the public exposure standards as determined by the International Commission on Non-Ionizing Radiation Protection. However, the electrical field strength on the roof adjacent to the high-voltage lines was significantly higher than that as measured on the other floors in the same buildings (p < 0.05). The electromagnetic radiation measurements of different monitoring points, under the same high-voltage lines, showed the location which is nearer the high-voltage line maintain a consistently higher level of radiation than the more distant locations (p < 0.05). Electromagnetic radiation generated by high-voltage lines decreases proportionally to the distance from the lines. The buildings can to some extent shield (or absorb) the electric fields generated by high-voltage lines nearby. The electromagnetic radiation intensity near high-voltage lines may be mitigated or intensified by the manner in which the high-voltage lines are set up, and it merits attention for the potential impact on human health.

Pre-wired systems prove their worth

The 'new generation' of modular wiring systems from Apex Wiring Solutions have been specified for two of the world's foremost teaching hospitals - the Royal London and St Bartholomew's Hospital, as part of a pounds sterling 1 billion redevelopment project, to cut electrical installation times, reduce on-site waste, and provide a pre-wired, factory-tested, power and lighting system. HEJ reports.

Laser detection of electrical service safety in a single ZnO nanowire

The electrically induced quenching of the photoluminescence (PL) intensity and fracture in a single ZnO nanowire were investigated. As the applied voltage increases, the quenching of PL intensity and the red-shift of ultraviolet (UV) emission peak were clearly observed, which are explained by the current-induced Joule heating in the ZnO nanowire. By using this mechanism, the UV laser was successfully used to monitor the safe current density and identify the current-induced fracture in a single ZnO nanowire.

Printed wiring boards for mobile phones: characterization and recycling of copper

The popularization of mobile phones, combined with a technological evolution, means a large number of scrap and obsolete equipment are discarded every year, thereby causing economic losses and environmental pollution. In the present study, the printed wiring boards scrap of mobile phones were characterized in order to recycle some of the device components, using techniques of mechanical processing, hydrometallurgy and electrometallurgy. The use of the techniques of mechanical processing (milling, particle size classification, magnetic and electrostatic separation) was an efficient alternative to obtain a concentrated fraction (mainly iron in the magnetic fraction and copper in the conductive fraction) and another fraction containing polymers and ceramics. At the end of mechanical processing, a concentrated fraction of metals could be obtained with an average concentration of 60% copper. This concentrated fraction in metals was dissolved in aqua regia and sent to electrowinning to recover 92% of the dissolved copper. The obtained cathodes have a copper content above 95%, which demonstrates the technical feasibility of recovery of copper using the techniques of mechanical processing, hydrometallurgy and electrometallurgy.

Effect of gold wire bonding process on angular correlated color temperature uniformity of white light-emitting diode

Gold wire bonding is an important packaging process of lighting emitting diode (LED). In this work, we studied the effect of gold wire bonding on the angular uniformity of correlated color temperature (CCT) in white LEDs whose phosphor layers were coated by freely dispersed coating process. Experimental study indicated that different gold wire bonding impacts the geometry of phosphor layer, and it results in different fluctuation trends of angular CCT at different spatial planes in one LED sample. It also results in various fluctuating amplitudes of angular CCT distributions at the same spatial plane for samples with different wire bonding angles. The gold wire bonding process has important impact on angular uniformity of CCT in LED package.

Leapfrog cracking and nanoamorphization of ZnO nanowires during in situ electrochemical lithiation

The lithiation reaction of single ZnO nanowire (NW) electrode in a Li-ion nanobattery configuration was observed by in situ transmission electron microscopy. Upon first charge, the single-crystalline NW was transformed into a nanoglass with multiple glassy nanodomains (Gleiter, H. MRS Bulletin2009, 34, 456) by an intriguing reaction mechanism. First, partial lithiation of crystalline NW induced multiple nanocracks ∼70 nm ahead of the main lithiation front, which traversed the NW cross-section and divided the NW into multiple segments. This was followed by rapid surface diffusion of Li(+) and solid-state amorphization along the open crack surfaces. Finally the crack surfaces merged, leaving behind a glass-glass interface (GGI). Such reaction front instability also repeated in the interior of each divided segment, further subdividing the NW into different nanoglass domains (nanoamorphization). Instead of the profuse dislocation plasticity seen in SnO(2) NWs (Science2010, 330, 1515), no dislocation was seen and the aforementioned nanocracking was the main precursor to the electrochemically driven solid-state amorphization in ZnO. Ab initio tensile decohesion calculations verified dramatic lithium embrittlement effect in ZnO, but not in SnO(2). This is attributed to the aliovalency of Sn cation (Sn(IV), Sn(II)) in contrast to the electronically more rigid Zn(II) cation.

Meta-analysis of the effectiveness of marked wire in reducing avian collisions with power lines

Collisions of birds with power transmission and distribution lines have been documented for many species, and cause millions of casualties worldwide. Attempts to reduce mortality from such collisions include placing bird flight diverters (i.e., wire markers in the form of, e.g., spirals, swivels, plates, or spheres) on static and some electrified wires to increase their visibility. Although studies of the effectiveness of such devices have yielded contradictory results, the implementation of flight diverters is increasing rapidly. We reviewed the results of studies in which transmission or distribution wires were marked and conducted a meta-analysis to examine the effectiveness of flight diverters in reducing bird mortality. We included in our meta-analysis all studies in which researchers searched for carcasses of birds killed by a collision with wires. In those studies that also included data on flight frequency, we examined 8 covariates of effectiveness: source of data, study design, alternate design (if marked and unmarked spans were alternated in the same line), periodicity of searches for carcasses, width of the search transect, and number of species, lines, and stretches of wire searched. The presence of flight diverters was associated with a decrease in bird collisions. At unmarked lines, there were 0.21 deaths/1000 birds (n =339,830) that flew among lines or over lines. At marked lines, the mortality rate was 78% lower (n =1,060,746). Only the number of species studied had a significant influence on effect size; this was larger in studies that addressed more species. When comparing mortality at marked and unmarked lines, we recommend use of the same time intervals and habitats and standardizing the periodicity of carcass searches.

Chemical oxidation of cable insulating oil contaminated soil

Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidation leads to partial removal of highly contaminated soil, therefore chemical oxidation was investigated and optimized aiming at a subsequent bioremediation treatment. Chemical oxidation of cable oil was studied with liquid H(2)O(2) and solid CaO(2) as well as permanganate at pH 1.8, 3.0 and 7.5. Liquid H(2)O(2) most effectively removed cable oil at pH 7.5 (24%). At pH 7.5 poor oil removal of below 5% was observed with solid CaO(2) and permanganate within 2d contact time, whereas 18% and 29% was removed at pH 1.8, respectively. A prolonged contact time of 7d showed an increased oil removal for permanganate to 19%, such improvement was not observed for CaO(2). Liquid H(2)O(2) treatment at pH 7.5 was most effective with a low acid use and was best fit to a subsequent bioremediation treatment. To further optimize in situ chemical oxidation with subsequent bioremediation the effect of the addition of the iron catalyst and a stepwise liquid H(2)O(2) addition was performed. Optimization led to a maximum of 46% cable oil removal with 1469mM of H(2)O(2), and 6.98mM Fe(II) chelated with citric acid (H(2)O(2):FeSO(4)=210:1 (molmol(-1)). The optimum delivery method was a one step addition of the iron catalyst followed by step wise addition of H(2)O(2).

An interferometric current sensor based on optical fiber micro wires

In this paper we demonstrate a compact current sensor using the optic fiber micro wire, based on the idea of interferometrically measuring the thermally induced optical phase shifts as a result of heat produced due to the flow of electric current over short transit lengths. A responsivity of 1.28 x 10(-4) rad/I(2) at 50 Hz of current signal has been shown, with capability of measuring alternating current signals up to 500 Hz.

An unusual foreign body in the urinary bladder

A coiled electric cable was removed from the urinary bladder of a 35-year-old male, electrician by profession. Psychiatric evaluation revealed normal childhood and no psychiatric illness. Proper management by both a urologist and a psychiatrist is required in these cases.

A standardized method for measuring the force required to join wire harnesses and sparkplugs

Understanding the forces required to insert a sparkplug wire (wire) onto a sparkplug (plug), independent of worker variation, is important for ergonomists, engineers, and designers. This paper describes a methodology for measuring the forces required to seat a wire onto a plug. A three-axis programmable mill was used to insert wires onto plugs mounted on a force transducer. Inflection points and slopes of the force-displacement curves were found to correspond to mechanical events as the plug and wire were joined. These events were further isolated by dissecting the wires to better understand the force contribution of each wire component. Liner superposition was then used to show that each of these force elements may be added to estimate the total force required to seat a wire onto a plug. This methodology may be used to quantify the effects of design choices, lubricants (wet and dry), and pre-working on axial insertion forces associated with sparkplugs and other insertions. This paper does not address worker abilities or variation, however, the methodology and equipment described may provide a foundation for the exploration of worker ability, variation and work techniques.