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Objective LIA-ANA-Profile-17S is a multiplex line immunoassay that simultaneously detects 17 antinuclear antibodies (ANAs) against extractable nuclear antigens (ENAs). We evaluated the utility of LIA-ANA-Profile-17S as a supplement to ANA indirect immunofluorescence (IIF) and EliA ENA (a fluorescence enzyme immunoassay) for diagnosis of ANA-associated rheumatic diseases. Methods Sera were collected from 245 patients referred for an ANA IIF test. LIA-ANA-Profile-17S results were compared with those of EliA ENA. The kappa coefficients, agreement rates, and diagnostic performance of these tests were assessed for systemic lupus erythematosus (SLE) and Sjögren’s syndrome (SjS). Results We observed almost perfect interassay agreement for antibodies against Ro52/Ro60, CENP-B, and Scl-70 (kappa = 0.91, 0.97, and 1.00, respectively); strong agreement for anti-SS-B/La antibody (kappa = 0.81); and relatively low agreement for other antibodies, including those against dsDNA, Sm, RNP, and Jo-1. For SLE diagnosis, LIA-ANA-Profile-17S showed lower sensitivity and similar specificity compared with EliA ENA. The sensitivity and specificity of these two assays were similar for SjS diagnosis. Conclusions The specificity of LIA-ANA-Profile-17S was enhanced when combined with ANA IIF and was comparable with that of EliA ENA. LIA-ANA-Profile-17S showed relatively good agreement with EliA ENA. In combination with ANA IIF, these assays showed enhanced diagnostic performance.

(1-3)-β-D-glucan (BDG) is a major biomarker of invasive fungal diseases (IFDs), which are life-threatening for immunodeficient patients. We compared the clinical performance of two BDG-detection assays. The precision, linearity, reference interval, and limit of quantitation of the Wako BDG assay were analyzed and the performance was compared with that of the Goldstream BDG assay using 272 clinical serum samples. The repeatability, within-laboratory imprecision, and limit of quantitation of the Wako BDG assay were 3.8%, 5.9%, and 7.35 pg/mL, respectively (linearity, 23.8–557 pg/mL; R2 = 0.998). The correlation coefficient, slope, and y-intercept for the Wako BDG assay versus Goldstream BDG assay were 0.29, 3.82, and 0.04, respectively. The sensitivity and specificity were 43.8% and 94.9% for the Wako BDG assay and 39.6% and 83.5% for the Goldstream BDG assay, respectively. In clinical settings, the Wako BDG assay is suitable for diagnosing patients with IFDs.

Cytomegalovirus (CMV) nucleic acid amplification testing is important for CMV infection diagnosis and management. CMV DNA is found in plasma and various other fluids, including urine. If CMV can be reliably detected in urine, it may be considered a non-invasive alternative to blood tests. The cobas 6800 system (Roche Diagnostics, Mannheim, Germany) is a Food and Drug Administration-approved testing platform for measuring CMV DNA in plasma.To evaluate the analytical performance of the cobas 6800 system and compare the clinical feasibility of CMV detection in plasma and urine samples.Imprecision, linearity, limit of quantitation (LOQ), and cross-reactivity of the cobas 6800 system were assessed, and reference interval verification was performed. Plasma CMV DNA quantification was compared to CMV DNA values in urine samples obtained from 129 pediatric patients (18 years of age) from March 2020 to May 2020 at a tertiary hospital.The assay precision was within the acceptable range. Linearity was observed within the tested concentration range (2.36-6.33 log IU/mL) with a coefficient of determination of 0.9972. The LOQ was 34.5 IU/mL. The assay did not show cross-reactivity with 15 other viruses. Plasma and urine detection results were stratified into three categories: negative,LOQ, and positive to analyze the degree of agreement with the results. The quadratic weighted kappa value was 0.623 (P = 0.000), showing substantial concurrence.The cobas 6800 system offers good sensitivity, precision, and linearity and is suitable for monitoring CMV viral loads in the plasma and urine samples.

The task of detecting and classifying highly maneuverable and unidentified underwater targets in complex environments is significant in active sonar systems. Previous studies have applied many detection schemes to this task using signals above a preset threshold to separate targets from clutter, this is because a high signal-to-noise ratio (SNR) target has sufficient feature vector components to be separated out. However, in real environments, the received target return&rsquo, s SNR is not always above the threshold. Therefore, a target detection algorithm is needed for varied target SNR conditions. When the clutter energy is too strong, false detection can occur, and the probability of detection is reduced due to the weak target signature. Furthermore, since a long pulse repetition interval is used for long-range detection and ambient noise tends to be high, classification processing for each ping is needed. This paper proposes a multilayer classification algorithm applicable to all signals in real underwater environments above the noise level without thresholding and verifies the algorithm&rsquo, s classification performance. We obtained a variety of experimental data by using a real underwater target and a hull-mounted active sonar system operated on Korean naval ships in the East Sea, Korea. The detection performance of the proposed algorithm was evaluated in terms of the classification rate and false alarm rate as a function of the SNR. Since experimental environment data, including the sea state, target maneuvering patterns, and sound speed, were available, we selected 1123 instances of ping data from the target over all experiments and randomly selected 1000 clutters based on the distribution of clutters for each ping. A support vector machine was employed as the classifier, and 80% of the data were selected for training, leaving the remaining data for testing. This process was carried out 1000 times. For the performance analysis and discussions, samples of scatter diagrams and feature characteristics are shown and classification tables and receiver operation characteristic (ROC) curves are presented. The results show that the proposed algorithm is effective under a variety of target strengths and ambient noise levels.

An analog maximum power point tracking (MPPT) circuit for a thermoelectric generator (TEG) is proposed. We show that the peak point of the voltage conversion gain of a boost DC–DC converter with an input voltage source having an internal resistor is the maximum power point of the TEG. The key characteristic of the proposed MPPT controller is that the duty ratio of the input clock pulse to the boost DC–DC converter shifts toward the maximum power point of the TEG by seeking the peak gain point of the boost DC–DC converters. The proposed MPPT technique provides a simple and useful analog MPPT solution, without employing digital microcontroller units.

A digital coreless maximum power point tracking (MPPT) circuit for thermoelectric generator unit is proposed and fabricated. The experimental and simulation results from the proposed MPPT circuit dealt with rapid variation of temperature and abrupt changes of load current have shown that the proposed method allows stable operation with high power transfer efficiency. The proposed MPPT circuit has a merit in cost and miniaturization of a system compared to conventional MPPT algorithms thanks to an analog tracking circuit without digital controller unit for calculating peak power point by iterative methods.

As indicators of obesity, waist circumference (WC), body mass index (BMI), and adiponectin are well-known risk factors for diabetes mellitus. The objectives of this study were to measure the independent association between these obesity indicators and diabetes and to examine the combined effect of these indicators on diabetes in a Korean population. The WC, BMI, and serum adiponectin were measured in 4459 healthy Koreans and were classified into tertile groups for men and women. The independent and combined associations of the obesity indicators with diabetes were measured using logistic regression analyses. Diabetes was defined as fasting serum glucose greater than 126 mg/dL or taking medication. Levels of adiponectin were inversely associated with BMI and WC and directly associated with age and high-density lipoprotein (HDL) cholesterol (P < .001). After adjusting for age, BMI, WC, and other lifestyle factors, low levels of adiponectin were associated with an increased prevalence of diabetes. Further adjustment for HDL cholesterol and triglyceride attenuated this association in women but not men. The combined effects of WC and adiponectin on diabetes progressively increased; however, the interaction of these 2 variables was not statistically significant. The combined effect of BMI and adiponectin on diabetes showed similar results. These results suggest that adiponectin was associated with diabetes. The association was independent of BMI and WC and was partly modified by HDL and triglyceride. There were no effect modifications of adiponectin with WC and BMI on diabetes.

This cohort study of Koreans examines the relationship between smoking on atherosclerotic cardiovascular disease (ASCVD) and whether serum levels of total cholesterol modify the impact of smoking on ASCVD. A 10-year prospective cohort study was carried out on 234,399 Korean women, ranging 40-69 years of age who received health insurance from the National Health Insurance Corporation and had a medical evaluation in 1993. The main outcome measures were hospital admissions and deaths from ischemic heart disease (IHD), cerebrovascular disease (CVD), and total ASCVD. At baseline, 13,696 (5.8%) were current smokers and 105,755 (45.1%) had a total cholesterol

The authors conducted a 10-year prospective cohort study of mortality in relation to white blood cell counts of 437,454 Koreans, aged 40–95 years, who received health insurance from the National Health Insurance Corporation and were medically evaluated in 1993 or 1995, with white blood cell measurement. The main outcome measures were mortality from all causes, all cancers, and all atherosclerotic cardiovascular diseases (ASCVD). Hazard ratios and 95% confidence intervals were calculated using Cox proportional hazards models with adjustment for age and potential confounders. During follow-up, 48,757 deaths occurred, with 15,507 deaths from cancer and 11,676 from ASCVD. For men and women, white blood cell count was associated with all-cause mortality and ASCVD mortality but not with cancer mortality. In healthy nonsmokers, a graded association between a higher white blood cell count and a higher risk of ASCVD was observed in men (highest vs. lowest quintile: hazard ratio ¼ 2.10, 95% confidence interval: 1.50, 2.94) and in women (hazard ratio ¼ 1.35, 95% confidence interval: 1.17, 1.56). In healthy smokers, a graded association between a higher white blood cell count and a higher risk of ASCVD was also observed in men (highest vs. lowest quintile: hazard ratio ¼ 1.46, 95% confidence interval: 1.25, 1.72). These findings indicate that the white blood cell count is an independent risk factor for all-cause mortality and for ASCVD mortality. arteriosclerosis; cardiovascular diseases; death; leukocytes; neoplasms

Proposed is a helical piezoelectric structure for a highly stretchable energy harvester to be applied on the human body. The proposed device consists of two counter-wound helical structures around a zcore structure made of an elastic fabric string. The inner fabric helix is used to separate the outer piezoelectric helix from the core to obtain a highly stretchable device. When stretched by 60% of its initial length, the device generates a maximum output voltage and power of 140 Vp-p and 0.6 mW, respectively, at an operation frequency of 4 Hz.

The Republic of Korea has proposed and designed a helium cooled molten lithium (HCML) test blanket module (TBM) to be tested in the ITER. Ferritic Martensitic Steel (FMS) and beryllium are designed to be used as structural material and armor for the TBM first wall (FW) in this design, respectively. In order to develop the fabrication method for the TBM FW, the joining methods of FMS to FMS and Be to FMS have been developed with hot istotatic pressing (HIP). For joining FMS to FMS, mock-ups were fabricated with an HIP (1050 °C, 100 MPa, 2 hours). For joining Be to FMS, two mock-ups were fabricated with the same method (580 °C, 100 MPa, 2 hours) using different interlayers. Then, in order to evaluate the integrity of the fabricated mock-ups, they were tested at the high heat flux (HHF) test facilities, KoHLTs (Korea Heat Load Test) under 1.0 MW/m2 and 0.5 MW/m2 heat fluxes of up to 1000 cycles.Copyright © 2010 by ASME

Background In the diagnosis of atopic diseases, allergen detection is a crucial step. Multiple allergen simultaneous test-chemiluminescent assay (MAST-CLA) is a simple and noninvasive method for in vitro screening of allergen-specific IgE antibodies. Methods The Korean Inhalant Panel test on 20 patients and Food Panel test on 19 patients were performed using the conventional manual MAST-CLA kit and the new automated MAST-CLA method (automated AP720S system for the Optigen Assay; Hitachi Chemical Diagnostics, Inc., USA) simultaneously. The results were evaluated for positive reactivity and concordance. Results The results of inhalant panel gave a relatively higher class level result than the food panel. The 8 patients out of 20 (40%) of the inhalation panel, and 9 patients out of 18 (47.4%) of the food panel showed 100% concordance between the 2 systems. Eighteen patients (90%) of the Inhalation Panel and sixteen patients (84.2%) of the Food Panel showed more than 91% concordance. Conclusions These results suggest that the MAST-CLA assay using the new, automated AP720S analyzer performs well, showing a high concordance rate with conventional MAST-CLA. Compared to manual MAST-CLA, the automated AP720S system has a shorter assay time and uses a smaller serum volume (500 µl) along with other conveniences.

BACKGROUND Obesity is associated with diverse health risks, but the role of body weight as a risk factor for death remains controversial. METHODS We examined the association between body weight and the risk of death in a 12-year prospective cohort study of 1,213,829 Koreans between the ages of 30 and 95 years. We examined 82,372 deaths from any cause and 48,731 deaths from specific diseases (including 29,123 from cancer, 16,426 from atherosclerotic cardiovascular disease, and 3362 from respiratory disease) in relation to the body-mass index (BMI) (the weight in kilograms divided by the square of the height in meters). RESULTS In both sexes, the average baseline BMI was 23.2, and the rate of death from any cause had a J-shaped association with the BMI, regardless of cigarette-smoking history. The risk of death from any cause was lowest among patients with a BMI of 23.0 to 24.9. In all groups, the risk of death from respiratory causes was higher among subjects with a lower BMI, and the risk of death from atherosclerotic cardiovascular disease or cancer was higher among subjects with a higher BMI. The relative risk of death associated with BMI declined with increasing age. CONCLUSIONS Underweight, overweight, and obese men and women had higher rates of death than men and women of normal weight. The association of BMI with death varied according to the cause of death and was modified by age, sex, and smoking history.

Pancreatic cancer is one of the most fatal human cancers and continues to be a major unsolved health problem. The goal of this study was to estimate the independent effects and interactions between cigarette smoking and diabetes on the risk of pancreatic cancer in Korean male population. Cigarette smoking and the risk of incidence and death from pancreatic cancer were examined in a 10-year prospective cohort study of 446,407 Korean men aged 40 to 65 years who received health insurance from the National Health Insurance Corporation and who had a medical evaluation in 1992. Relative risks (RR) and 95% confidence intervals (CI) were calculated using a Cox proportional hazards model after adjusting for age, body mass index, exercise and alcohol use. Current smoking was associated with an increased risk of incidence (RR = 1.7, 95% CI = 1.6-1.9) and mortality (RR = 1.6, 95% CI = 1.4-1.7) from pancreatic cancer. The RR for pancreatic cancer increased with both duration and amount of smoking. Diabetes was also associated with an increased risk of both incidence (RR = 1.8, 95% CI = 1.5-2.2) and mortality (RR = 1.7, 95% CI = 1.4-2.1) from pancreatic cancer. There was no interaction between smoking and fasting serum glucose in terms of pancreatic cancer risk. Thus, our prospective study has demonstrated that cigarette smoking and elevated fasting serum glucose are independently associated with an increased risk of pancreatic cancer in a large cohort of Korean males.

An offshore wind farm will be constructed in the Yellow Sea, west of Korean Peninsula, where there are extensive fishing activity and numerous fishery farms. To study the effect of underwater piling noise on fishing and marine lives, we model the pile driving noise propagation using coupled FE and PE model. The near-field noise is computed by FE model, considering detailed specifications of the pile driving system. We apply 2D axis-symmetric geometry and utilize acoustic structure interaction analysis in the frequency domain. The FE results are used to compose the starting field for PE model, where appropriate range selection is an important factor to cover most of the contributing ray paths. Extrapolation technique to compensate the lack of FE data and the numerical filtering method to smooth the FE result are discussed. In the far-field, the noise propagation is modeled by the split step Pade PE algorithm. The improved PE starting field seems to give refined result than previous coupled model.

Purpose Tumor marker concentrations in a given specimen measured by different analyzers vary according to assay methods, epitopes for antibodies used, and reagent specificities. Although great effort in quality assessment has been instituted, discrepancies among results from different analyzers are still present. We evaluated the assay performance of the UniCel™ DxI 800 automated analyzer in measuring the alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (CA) 125, CA 15-3 and CA 19-9 tumor markers. Materials and Methods The linearity and precision performance of the five tumor marker assays were evaluated, and concentrations of the respective markers as measured by DxI were compared to those measured by other conventional analyzers (ADVIA Centaur™ and Vitros™ ECi) using 200 specimens collected from 100 healthy persons and 100 patients with respective cancers. Results The linear fits for all five tumor markers were statistically acceptable (F=4648 for AFP, F=15846 for CEA, F=6445 for CA 125, F=2285 for CA 15-3, F=7459 for CA 19-9; p

OBJECTIVES This study aimed to measure the association between the adiponectin, C1Q and collagen domain-containing (ADIPOQ) gene variants and obesity in Koreans. METHODS Three single nucleotide polymorphisms located in the ADIPOQ gene were genotyped in a population-based cross-sectional study of 986 healthy Koreans. Three different case-control groups (i.e. G1, G2, and G3) were defined according to body mass index (BMI) and serum adiponectin levels. Allelic and genotypic associations of this gene with obesity were measured using multivariate logistic regression analyses in each group. RESULTS The G allele of -11377C>G, a polymorphism located in the promoter region of the ADIPOQ gene (odds ratio (OR), 1.48; 95% confidence interval, 1.13-1.94) and most haplotypes including this allele significantly increased the risk for obesity. However, the OR decreased from 3.98 (G1 group) to 2.90 (G2 group) and 2.30 (G3 group) when a less strict definition of obesity was used. Most haplotypes, including this allele, significantly increased the risk of obesity. The statistical evidence from the GG genotype of -11377C>G (OR, 3.98) and the GT/GT diplotype composed of -11377G>C and +45T>G (OR, 5.20) confirmed the contribution of the G allele toward a predisposition for obesity. CONCLUSION These results suggest the contribution of the ADIPOQ gene toward susceptibility to obesity in healthy Koreans. The high-risk genotypes and haplotypes identified here may provide more information for identifying individuals who are at risk of obesity.