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In the potential induced degradation (PID) phenomenon, the output power of a photovoltaic (PV) module decreases due to the high potential difference between the PV system and the ground. This voltage forcefully moves the positive charge in the module to the surface of the solar cell. The accumulated charge leads to the performance deterioration of the module, namely, PID of the module. We conducted a study to accurately predict the output reduction of the module operating in various installation conditions coming from the PID phenomenon. We investigated the leakage current flowing through front glass laminated with encapsulation material simultaneously exposed to various performance conditions of the PV system, namely, relative humidity, temperature, and applied voltage, which have an important effect on the PID of the module. The degradation of the module coming from PID was calculated on the basis of the obtained leakage current. To confirm the calculated data, modules with one solar cell were manufactured and the power loss results of the modules' exposure to various PID generation experiments were compared with the expected results. The results showed that we could predict the degradation of the modules by PID within a 2% tolerance under the PV system installation conditions. [ABSTRACT FROM AUTHOR]

The article presents a study to determine the factors affecting archery performance by calculating the importance of these factors in Korean archery using Delphi technique and the analytic hierarchy process(AHP). Confirmatory factor analysis was conducted among 463 archers in meeting with 20 archery experts. Out of the 11 mental factors affecting performance, confidence proved to be more important than concentration, emotion control and positive thinking.

This study examined the effects of 16-week combined exercise programme on body composition, physical fitness and cognitive function of Korean children. The 20 participants were randomly assigned to the Combined Exercise Training (CET) (resistance exercise and aerobics) group (n=10) or a contrai group (CG, n=10). The CET group performed 90-min exercise sessions twice per week for 16 weeks, including 40min of resistance exercise, 40min of aerobic exercise and 10min warm-up and cool-down. The CG did not participate in any exercise or physical activity. Body composition variables (weight, body mass index, fat-free mass, per cent body fat, and basal metabolic rate) were measured using bio-electrical impedance analysis. Subjects underwent a physical fitness test consisting of sit-ups, grip strength, sit-and-reach, standing long jump, side-steps and isokinetic leg extension strength. The cognitive function test consisted of electro-encephalography (EEG) activation and the Stroop test. Significant interaction effects (time x group) on EEG activation (brain activity) in the Fpl (p=0.034), F3 (p=0.028), and C4 (p=0.013) areas and Stroop test (cognitive function) (p =0.005) were observed in the CET group compared to the CG. There were no interaction effects (time x group) on body composition or physical fitness variables. The CET affected the cognitive function of Korean children positively. [ABSTRACT FROM AUTHOR]

Polyglandular autoimmune syndrome is defined as multiple endocrine gland insufficiencies accompanied by autoimmune diseases of the endocrine and nonendocrine system. After Schmidt introduced a case of nontuberculosis adrenal gland dysfunction with thyroiditis in 1926, Neufeld defined polyglandular autoimmune syndrome by I, II, and III subtypes in 1980 by their presentation of occurrence age, heredity methods, relationship with human leukocyte antigen, and accompanying diseases. We report a case of a 32-year-old female with polyglandular autoimmune syndrome III accompanied by type 1 diabetes mellitus that was treated with insulin (36 units per day) for 11 years. She had insulin deficiency and Hashimoto thyroiditis as an autoimmune disorder. In addition, she had several features similar to Albright's hereditary osteodystrophy including short stature, truncal obesity, round face, short neck, low intelligence (full IQ 84), and decreased memory. Although Albright's hereditary osteodystrophy is morphological evidence of pseudohypoparathyroidism or pseudopseudohypoparathyroidism, she had primary hypoparathyroidism on laboratory results. Here, we report a case of polyglandular autoimmune syndrome III with type 1 diabetes mellitus, autoimmune thyroiditis, and primary hypoparathyroidism, accompanied by clinical features similar to Albright's hereditary osteodystrophy. [ABSTRACT FROM AUTHOR]

In this paper, a novel circularly polarized Spidron fractal slot antenna array developed for broadband satellite communication in the Ku-band is discussed. A Spidron fractal slot configuration was utilized as a single radiating element to achieve circularly polarized radiation. The effects of altering the feeding position on the resonance behavior and the radiative characteristics were assessed. As a consequence, the design was expanded from a single element to a 2x2 subarray and further to a 4x4 array in order to enhance the bandwidth performance of the antenna when integrated with a sequential feeding network. Two prototype arrays were fabricated and tested, and measurements revealed that the 2x2 subarray has a 10-dB reflection coefficient bandwidth between 10 and 14.28 GHz, 3 dB axial ratio bands between 10.15 and 11.15 GHz and between 11.75 and 13.92 GHz, and a maximum gain of 11.4 dB at 13 GHz. The results for the 4x4 array indicated that both the 10-dB reflection coefficient and 3 dB axial ratio bandwidths cover the entire operating frequency from 10 to 15GHz in the Ku-band. The maximum gain for the 4x4 array was 15.63 dB at 12.6 GHz. [ABSTRACT FROM AUTHOR]

A planar meander-line monopole antenna was designed for wireless Universal Serial Bus (USB) dongle devices. The proposed antenna shows dual-wideband resonant characteristics and supports the WiBro, Bluetooth, WLAN, WiMAX, and S-DMB (Satellite Digital Multimedia Broadcast) services. The designed antenna measures 19 × 50 × 1 mm3, which is suitable for compact USB dongles. The measured 2:1 bandwidths of the voltage standing wave ratio are 18.1% (2.26–2.71 GHz) and 16.4% (5.09–6.0 GHz). The measured peak gain is 3.49 dBi, and efficiency is higher than 56%. The radiation patterns are also nearly omni-directional. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2279–2282, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25430 [ABSTRACT FROM AUTHOR]

Motivation: Although clinical aspirations for new technology to accurately measure and diagnose Parkinsonian tremors exist, automatic scoring of tremor severity using machine learning approaches has not yet been employed. Objective: This study aims to maximize the scientific validity of automatic tremor-severity classification using machine learning algorithms to score Parkinsonian tremor severity in the same manner as the unified Parkinson’s disease rating scale (UPDRS) used to rate scores in real clinical practice. Approach: Eighty-five PD patients perform four tasks for severity assessment of their resting, resting with mental stress, postural, and intention tremors. The tremor signals are measured using a wristwatch-type wearable device with an accelerometer and gyroscope. Displacement and angle signals are obtained by integrating the acceleration and angular-velocity signals. Nineteen features are extracted from each of the four tremor signals. The optimal feature configuration is decided using the wrapper feature selection algorithm or principal component analysis, and decision tree, support vector machine, discriminant analysis, and k-nearest neighbour algorithms are considered to develop an automatic scoring system for UPDRS prediction. The results are compared to UPDRS ratings assigned by two neurologists. Main results: The highest accuracies are 92.3%, 86.2%, 92.1%, and 89.2% for resting, resting with mental stress, postural, and intention tremors, respectively. The weighted Cohen’s kappa values are 0.745, 0.635 and 0.633 for resting, resting with mental stress, and postural tremors (almost perfect agreement), and 0.570 for intention tremors (moderate). Significance: These results indicate the feasibility of the proposed system as a clinical decision tool for Parkinsonian tremor-severity automatic scoring. [ABSTRACT FROM AUTHOR]

Mycolactone, a polyketide molecule produced by Mycobacterium ulcerans, is the etiological agent of Buruli ulcer. This lipid toxin is endowed with pleiotropic effects, presents cytotoxic effects at high doses, and notably plays a pivotal role in host response upon colonization by the bacillus. Most remarkably, mycolactone displays intriguing analgesic capabilities: the toxin suppresses or alleviates the pain of the skin lesions it inflicts. We demonstrated that the analgesic capability of mycolactone was not attributable to nerve damage, but instead resulted from the triggering of a cellular pathway targeting AT2 receptors (angiotensin II type 2 receptors; AT2R), and leading to potassium-dependent hyperpolarization. This demonstration paves the way to new nature-inspired analgesic protocols. In this direction, we assess here the hyperpolarizing properties of mycolactone on nociceptive neurons. We developed a dedicated medium-throughput assay based on membrane potential changes, and visualized by confocal microscopy of bis-oxonol-loaded Dorsal Root Ganglion (DRG) neurons. We demonstrate that mycolactone at non-cytotoxic doses triggers the hyperpolarization of DRG neurons through AT2R, with this action being not affected by known ligands of AT2R. This result points towards novel AT2R-dependent signaling pathways in DRG neurons underlying the analgesic effect of mycolactone, with the perspective for the development of new types of nature-inspired analgesics.