• Advances in concrete construction
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• v.9 no.3
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• pp.289-299
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• 2020

To investigate the long-term behavior of eccentrically loaded RC columns, which are more realistic in practice than concentrically loaded RC columns, long-term eccentric loading tests were conducted for 10 RC columns. Test parameters included concrete compressive strength, reinforcement ratio, bar yield strength, eccentricity ratio, slenderness ratio, and loading pattern. Test results showed that the strain and curvature of the columns increased with time, and concrete forces were gradually transferred to longitudinal bars due to the creep and shrinkage of concrete. The long-term behavior of the columns varied with the test parameters, and long-term effects were more pronounced in the case of using the lower strength concrete, lower strength steel, lower bar ratio, fewer loading-step, higher eccentricity ratio, and higher slenderness ratio. However, in all the columns, no longitudinal bars were yielded under service loads at the final measuring day. Meanwhile, the numerical analysis modeling using the ultimate creep coefficient and ultimate shrinkage strain measured from cylinder tests gave quite good predictions for the behavior of the columns.

• Structural Engineering and Mechanics
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• v.75 no.4
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• pp.445-454
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• 2020

Structural damage identification (SDI) is a crucial step in structural health monitoring. However, some of the existing SDI methods cannot provide enough identification accuracy and efficiency in practice. A novel whale optimization algorithm (WOA) based method is proposed for SDI by weighting modal data and flexibility assurance criterion in this study. At first, the SDI problem is mathematically converted into a constrained optimization problem. Unlike traditional objective function defined using frequencies and mode shapes, a new objective function on the SDI problem is formulated by weighting both modal data and flexibility assurance criterion. Then, the WOA method, due to its good performance of fast convergence and global searching ability, is adopted to provide an accurate solution to the SDI problem, different predator mechanisms are formulated and their probability thresholds are selected. Finally, the performance of the proposed method is assessed by numerical simulations on a simply-supported beam and a 31-bar truss structures. For the given multiple structural damage conditions under environmental noises, the WOA-based SDI method can effectively locate structural damages and accurately estimate severities of damages. Compared with other optimization methods, such as particle swarm optimization and dragonfly algorithm, the proposed WOA-based method outperforms in accuracy and efficiency, which can provide a more effective and potential tool for the SDI problem.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.5
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• pp.3315-3318
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• 2013

Gall bladder carcinoma is the most common cancer of biliary tree, characterized by rapid progression and a very high mortality rate. Detection at an early stage, however, is indicative of a very good prognosis and prolonged survival. The practice of histopathological examination of gall bladder specimens removed for clinically benign conditions and its usefulness has been a subject of controversy. The present prospective study was carried out over a period of four years in order to find out the incidence of unsuspected gallbladder carcinoma in cholecystectomy specimens received in our histopathology laboratory and to analyze their clinico-pathological features. A total of 4,115 cases were examined. Incidentally detected cases comprised 0.44%, which accounted for 72% of all gall bladder carcinomas detected. The majority were in an early, surgically resectable stage. From the results of this study we recommend that in India and other countries with relatively high incidences of gall bladder carcinoma, all cholecystectomy specimens should be submitted to histopathology laboratory, as this is the only means by which malignancies can be detected at an early, potentially curable stage.

• Tuberculosis and Respiratory Diseases
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• v.79 no.3
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• pp.134-142
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• 2016

In recent years, in spite of medical advancement, tuberculosis (TB) remains a worldwide health problem. Although many laboratory methods have been developed to expedite the diagnosis of TB, delays in diagnosis remain a major problem in the clinical practice. Because of the slow growth rate of the causative agent Mycobacterium tuberculosis, isolation, identification, and drug susceptibility testing of this organism and other clinically important mycobacteria can take several weeks or longer. During the past several years, many methods have been developed for direct detection, species identification, and drug susceptibility testing of TB. A good understanding of the effectiveness and practical limitations of these methods is important to improve diagnosis. This review summarizes the currently-used advances in non-molecular and molecular diagnostics.

• Journal of The Korea Institute of Healthcare Architecture
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• v.13 no.1
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• pp.7-15
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• 2007

The medicine is used for diagnosis, treatment or prevention of disease and consequently has an important influence upon human life and health. Its effectiveness and safety must be guaranteed. In order to achieve the facility that meets GMP, KFDA has provided standards for quality assurance of the manufacture, examination and tests of medical supplies. The result of this study were as follows : the GMP facilities are divided into work, lab/test and storage spaces, and the systematic corridor. The clean rooms are mainly installed in work and lab/test spaces, and maintain class 10,000 in average. The individual space for the procedures that requires class 100 is not provided as a separate division. Instead, they are performed in the clean bench of the laboratory.

• BMB Reports
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• v.46 no.7
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• pp.335-337
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• 2013

Scientists planning research that involves the use of animals are required by international and/or national law to examine the possibilities for the implementation of Replacement, Reduction and/or Refinement (the Three Rs principles of Russell and Burch) in experiments for research, testing, and education. There are two Korean laws legislating humane use of animals and ethical review prior to animal experiments. This report reviews current practice of the literature search by the researchers and protocol review by the Institutional Animal Care and Use Committees on the Replacement, Reduction and Refinement alternatives in Korea. The promotion and protection of the laboratory animals are one of the core competencies of investigators exploring the ethical conduct of research and good science.

• YAKHAK HOEJI
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• v.47 no.2
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• pp.104-109
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• 2003

The present paper reviews the notion and comparison of the Korea Food and Drug Administration(KFDA) general pharmacology and the International Conference on Harmonisation (ICH) safety pharmacology. General pharmacology or safety pharmacology is termed the study to determine the potential of a compound to induce adverse pharmacological effects. KFDA general pharmacology studies have been considered an important component in drug safety assessment and these were originally referred to those designed to examine effects other than the primary therapeutics effect of a drug candidate. The KFDA notified the Guideline for General Pharmacology in 1997. Safety pharmacology studies were focused on identifying adverse effects on physiological functions. In the ICH came into place S7A Safety Pharmacology Studies for Human Pharmaceuticals in 2001. A new chemical entity should be assessed for its side effects, initially in those physiological systems which are generally agreed to be the key systems that are essential for life; these "core system" include the central nervous system, cardiovascular system and respiratory system in safety pharmacology studies. These studies should be performed in compliance with Good Laboratory Practice (GLP).

• Proceedings of the PSK Conference
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• 2002.10a
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• pp.287.2-287.2
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• 2002

The safety pharmacological core battery studies of AS2-006A. a newly developed wound healing drug, were investigated according to the ICH S7A guidelines in compliance with Good Laboratory Practice(GLP) Regulations, The doses given were 0, 100. 300 and 1000 mg/kg and drugs were administered subcutaneously. The animals used for this study were mice, rats and guinea pigs. AS2-006A showed no effects on the central nervous system such as motor activity. behaviotal changes. coordination, sensory/motor reflex responses and body temperature. no effects on blood pressure(BP). heart rate(HR), and ECG profiles and respiratory system. it was concluded that AS2-006A possess no general pharmacological effects at all doses tested. (omitted)

• Steel and Composite Structures
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• v.42 no.1
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• pp.91-106
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• 2022

Concrete-filled square stainless steel tubes (CFSSST), which possess relatively large flexural stiffness, high corrosion resistance and require simple joint configurations and low maintenance cost, have a great potential in constructional applications. Despite that the use of stainless steel may result in high initial cost compared to their conventional carbon steel counterparts, the whole-life cost of CFSSST is however considered to be lower, which offers a competitive choice in engineering practice. In this paper, a comprehensive experimental and numerical program on 24 CFSSST stub column specimens, including 3 austenitic and 3 duplex stainless steel square hollow section (SHS) stub columns and 9 austenitic and 9 duplex CFSSST stub columns, has been carried out. Finite element (FE) models were developed to be used in parametric analysis to investigate the influence of the tube thickness and concrete strength on the ultimate capacities more accurately. Comparisons of the experimental and numerical results with the predictions made by design guides ACI 318, ANSI/AISC 360, Eurocode 4 and GB 50936 have been performed. It was found that these design methods generally give conservative predictions to the ultimate capacities of CFSSST stub columns. Improved calculation methods, developed based on the Continuous Strength Method, have been proposed to provide more accurate estimations of the ultimate resistances of CFSSST stub columns. The suitability of these proposals has been validated by comparison with the test results, where a good agreement between the predictions and the test results have been achieved.

• Clinical and Experimental Pediatrics
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• v.56 no.1
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• pp.19-25
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• 2013

Purpose: Childhood obesity is associated with nonalcoholic fatty liver disease (NAFLD), and it has become one of the most common causes of childhood chronic liver diseases which significant as a cause of liver related mortality and morbidity in children in the United States. The development of simpler and easier clinical indices for medical practice is needed to identify advanced hepatic fibrosis in childhood NAFLD instead of invasive method like liver biopsy. FibroScan and aspartate aminotransferase (AST)-to-platelet ratio index (APRI) have been proposed as a simple and noninvasive predictor to evaluate hepatic fibrosis in several liver diseases. APRI could be a good alternative to detect pathologic change in childhood NAFLD. The purpose of this study is to validate the efficacy of APRI for assessing hepatic fibrosis in childhood NAFLD based on FibroScan. Methods: This study included 23 children with NAFLD who underwent FibroScan. Clinical, laboratory and radiological evaluation including APRI was performed. To confirm the result of this study, 6 patients received liver biopsy. Results: Factors associated with hepatic fibrosis (stiffness measurement >5.9 kPa Fibroscan) were triglyceride, AST, alanine aminotransferase, platelet count, APRI and collagen IV. In multivariate analysis, APRI were correlated with hepatic fibrosis (>5.9 kPa). In receiver operating characteristics curve, APRI of meaningful fibrosis (cutoff value, 0.4669; area under the receiver operating characteristics, 0.875) presented sensitivity of 94%, specificity of 66%, positive predictive value of 94%, and negative predictive value of 64%. Conclusion: APRI might be a noninvasive, simple, and readily available method for medical practice to predict hepatic fibrosis of childhood NAFLD.