• Genomics & Informatics
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• v.18 no.3
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• pp.31.1-31.8
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• 2020

The coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has become a global pandemic. No specific therapeutic agents or vaccines for COVID-19 are available, though several antiviral drugs, are under investigation as treatment agents for COVID-19. The use of convalescent plasma transfusion that contain neutralizing antibodies for COVID-19 has become the major focus. This requires mass screening of populations for these antibodies. While several countries started reporting population based antibody rate, its simple point estimate may be misinterpreted without proper estimation of standard error and confidence intervals. In this paper, we review the importance of antibody studies and present the 95% confidence intervals COVID-19 antibody rate for the Korean population using two recently performed antibody tests in Korea. Due to the sparsity of data, the estimation of confidence interval is a big challenge. Thus, we consider several confidence intervals using Asymptotic, Exact and Bayesian estimation methods. In this article, we found that the Wald method gives the narrowest interval among all Asymptotic methods whereas mid p-value gives the narrowest among all Exact methods and Jeffrey's method gives the narrowest from Bayesian method. The most conservative 95% confidence interval estimation shows that as of 00:00 on September 15, 2020, at least 32,602 people were infected but not confirmed in Korea.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.4
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• pp.215-222
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• 2023

Augmented reality (AR), which integrates virtual media into reality, is increasingly utilized across various industrial sectors, thanks to advancements in 3D graphics and mobile device technologies. The IT industry is thus carrying out active R&D activities about AR platforms. Google plays a significant role in the AR landscape, with a focus on ARCore services. An essential aspect of ARCore is the use of anchors, which serve as reference points that help maintain the position and orientation of virtual objects within the physical environment. However, if the accuracy of anchor positioning is suboptimal when running AR content, it can significantly diminish the user's immersive experience. We are to assess the performance of these anchors in this study. To conduct the performance evaluation, virtual 3D objects, matching the shape and size of real-world objects, we strategically positioned ourselves to overlap with their physical counterparts. Images of both real and virtual objects were captured from five distinct camera trajectories, and ARCore's performance was analyzed by examining the difference between these captured images.

• Nutrition Research and Practice
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• v.17 no.5
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• pp.870-882
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• 2023

BACKGROUND/OBJECTIVES: Obesity is a major risk factor for metabolic syndrome, a global public health problem. Mentha canadensis (MA), a traditional phytomedicine and dietary herb used for centuries, was the focus of this study to investigate its effects on obesity. MATERIALS/METHODS: Thirty-five male C57BL/6J mice were randomly divided into 2 groups and fed either a normal diet (ND, n = 10) or a high-fat diet (HFD, n = 25) for 4 weeks to induce obesity. After the obesity induction period, the HFD-fed mice were randomly separated into 2 groups: one group continued to be fed HFD (n = 15, HFD group), while the other group was fed HFD with 1.5% (w/w) MA ethanol extract (n = 10, MA group) for 13 weeks. RESULTS: The results showed that body and white adipose tissue (WAT) weights were significantly decreased in the MA-supplemented group compared to the HFD group. Additionally, MA supplementation enhanced energy expenditure, leading to improvements in plasma lipids, cytokines, hepatic steatosis, and fecal lipids. Furthermore, MA supplementation regulated lipid-metabolism-related enzyme activity and gene expression, thereby suppressing lipid accumulation in the WAT and liver. CONCLUSIONS: These findings indicate that MA has the potential to improve diet-induced obesity and its associated complications, including adiposity, dyslipidemia, hepatic steatosis, and inflammation.

• BMB Reports
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• v.57 no.6
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• pp.263-272
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• 2024

Amyloid-β (Aβ) is one of the amyloidogenic intrinsically disordered proteins (IDPs) that self-assemble to protein aggregates, incurring cell malfunction and cytotoxicity. While Aβ has been known to regulate multiple physiological functions, such as enhancing synaptic functions, aiding in the recovery of the blood-brain barrier/brain injury, and exhibiting tumor suppression/antimicrobial activities, the hydrophobicity of the primary structure promotes pathological aggregations that are closely associated with the onset of Alzheimer's disease (AD). Aβ proteins consist of multiple isoforms with 37-43 amino acid residues that are produced by the cleavage of amyloid-β precursor protein (APP). The hydrolytic products of APP are secreted to the extracellular regions of neuronal cells. Aβ 1-42 (Aβ42) and Aβ 1-40 (Aβ40) are dominant isoforms whose significance in AD pathogenesis has been highlighted in numerous studies to understand the molecular mechanism and develop AD diagnosis and therapeutic strategies. In this review, we focus on the differences between Aβ42 and Aβ40 in the molecular mechanism of amyloid aggregations mediated by the two additional residues (Ile41 and Ala42) of Aβ42. The current comprehension of Aβ42 and Aβ40 in AD progression is outlined, together with the structural features of Aβ42/Aβ40 amyloid fibrils, and the aggregation mechanisms of Aβ42/Aβ40. Furthermore, the impact of the heterogeneous distribution of Aβ isoforms during amyloid aggregations is discussed in the system mimicking the coexistence of Aβ42 and Aβ40 in human cerebrospinal fluid (CSF) and plasma.

• The Korean Journal of Nuclear Medicine
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• v.25 no.2
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• pp.252-258
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• 1991

With HMPAO we have synthesized in our laboratory, we labelled $^{99m}Tc$ to canine leukocytes. Experimental abscess made by subcutaneous injection with Staphylococcus aureus was imaged with these $^{99m}Tc$ labelled leukocytes. Labelling efficiency of HMPAO with $^{99m}Tc$ was $66.2%{\pm}14.6%$ (N=9). Labelling efficiency of leukocytes with $^{99m}Tc-HMPAO$ was $54%{\pm}7.7%$ (N=7). Cell bound radioactivity in $^{99m}Tc-HMPAO$ labelled leukocytes was around 80% when these cells were incubated in plasma in vitro at $37^{\circ}C$ for 5 hours. In vivo cell bound activity was over 80% at 24 hours after injection. One day and four days after inoculation, uptake at the inflammatory focus was found with $^{99m}Tc$ labelled leukocytes. Uptake showed up in 4 hour image, and the uptake at the lesion was most prominent in 24 hour image. These findings show that in-house-synthesized HMPAO could be used for labelling leukocytes with $^{99m}Tc$, and that s$^{99m}Tc-HMPAO-labelled$ leukocytes were so stable and viable that inflammatory focus could be visualized with these $^{99m}Tc-labelled$ leukocytes.

• Nuclear Engineering and Technology
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• v.37 no.5
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• pp.401-422
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• 2005

We review here research and development progress achieved in US Plasma Chamber technology roughly over the last decade. In particular, we focus on two major programs carried out in the US: the APEX project (1998-2003) and the US ITER TBM activities (2003-present). The APEX project grew out of the US fusion program emphasis in the late 1990s on more fundamental science and innovation. APEX was commissioned to investigate novel technology concepts for achieving high power density and high temperature reactor coolants. In particular, the idea of liquid walls and the related research is described here, with some detailed examples of liquid metal and molten salt magnetohydrodynamic and free surface effects on flow control and heat transfer. The ongoing US ITER Test Blanket Module (TBM) program is also described, where the current first wall/blanket concepts being considered are the dual coolant lead lithium concept and the solid breeder helium cooled concepts, both using ferritic steel structures. The research described for these concepts includes both thermofluid MHD issues for the liquid metal coolant in the DCLL, and thermomechanical issues for ceramic breeder packed pebble beds in the solid breeder concept. Finally, future directions for ongoing research in these areas are described.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.07b
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• pp.1062-1065
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• 2004

The importance of display is becoming increasingly important due to the development of information and industry where it leads to diverse and abundant information in today's society. The demand and application range for FPD(Flat Panel Display), specifically represented by LCD(Liquid Crystal Display) and PDP(Plasma Display Panel), have been rapidly growing for its outstanding performance and convenience amongst many other forms of display. The current focus has been on OLED(Organic Light Emitting Diode) in the mobile form, which has just entered into mass production amid the different types of FPD. Many studies are being conducted in regards to device, vacuum evaporation, encapsulation, and drive circuits with the development of device as a matter of the utmost concern. This study develops a new type of light-emitting materials by synthesizing medical polymer organic chitosan and phosphor material CuS. Chitosan itself satisfies the Pool-Frenkel Effect, an I-V specific curve, with a thin film under $20{mu}m$, and demonstrates production possibility for a living body sensors solely with the thin film. Furthermore, it enables production possibility for EML of organic EL device(Emitting Layer) with liquid Green light emitting and Blue light emitting as a result of synthesis with phosphor material.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.5
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• pp.711-719
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• 2000

The characteristics of the exocrine pancreatic secretions in pigs and its hormonal regulation as influenced by dietary lipids are reviewed. There is clear evidence that the secretion of lipolytic enzymes is positively correlated with the amount of fat consumed by the pig. For example, there was an increase in the specific lipase activity by 83% after the dietary fat content was increased from 5% to 25%. Moreover, it was shown that also the quality of fat has an influence on exocrine pancreatic secretions. Peroxidized canola oil stimulated total lipase secretion much more than non-peroxidized oil. The influence of fatty acid composition on exocrine pancreatic secretions is discussed equivocally. Some authors showed that saturated fats stimulated the exocrine pancreatic secretions more than unsaturated. Others showed that the chain length of fatty acids had a strong influence on pancreatic secretions as well. Due to the different surgical methods used for sampling of pancreatic juice and wide variety of fats and oils used in these studies, direct comparisons between studies are extremely difficult to make. Plasma levels of hormones such as cholecystokinin (CCK), neurotensin (NT) and peptide YY (PYY) are influenced by the nutrient composition of the diet. With increasing amounts of fat present in the small intestine, the release of these hormones was stimulated. There is evidence that CCK release is dependent on the chain length of the fatty acids. Medium chain triglycerides stimulated the CCK release more than long chain triglycerides. Neurotensin was released more by unsaturated than by saturated fatty acids; similar results were observed for the PYY release. However, results are contradictory and further investigations are warranted that focus on the underlying mechanisms involved in the regulatory response of the exocrine pancreas to lipids of different origin.

• Natural Product Sciences
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• v.13 no.1
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• pp.17-22
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• 2007

Fresh unripe whole fruits of Luffa tuberosa (Roxb.) or Momordica tuberosa (Roxb.) Cogn. (Cucurbitaceae) were evaluated for the antidiabetic and hyperlipidemic potential in streptozotocin (STZ) induced diabetic rats. Diabetes was induced by administration of intra-peritoneal injection of streptozotocin at a dose of 55 mg/kg body weight. After the induction of diabetes aqueous extract of L.tuberosa (AELT) was administered orally at doses of 250 and 500 mg/kg. body weight/day for a period of 14 days. The Fasting blood glucose (FBG) levels, serum insulin levels, changes in body weight, food and liquid intake were measured. In diabetic rats, the AELT exhibited significant reduction in blood glucose levels. Biochemical assay of plasma total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDLc), low-density lipoprotein cholesterol (LDLc), glycogen content and glucose-6-phosphatase activity in liver were assessed. Antihyperlipidemia in diabetic rats after the extract supplementation was confirmed by significant reduction in the levels of above mentioned hyperlipidemic indicators. This study focus on the efficacy of L.tuberosa fruits for the management of experimental STZ induced diabetic rats and provides the scientific basis of ancient herbal therapy and use of these fruits as vegetable.

• Journal of Welding and Joining
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• v.29 no.1
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• pp.99-106
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• 2011

Joint strength between a solder ball and a pad on a substrate is one of the major factors which have effects on electronic device reliability. The effort to improve solder joint strength via surface cleaning, heat treatment and solder composition change have been in progress. This paper will discuss the method of solder ball joint strength improvement using LF hydrogen radical cleaning treatment and focus on the effects of surface treatment condition on the solder ball shear strength and interfacial reactions. In the joint without radical cleaning, voids were observed at the interface. However, the specimens cleaned by hydrogen-radical didn't have voids at the interface regardless of cleaning time. The shear strength between the solder ball and the pad was increased over 120%(about 800gf) when compared to that without the radical treatment (680gf) under the same reflow condition. Especially, at the specimen treated for 5minutes, ball shear strength was considerably increased over 150%(1150gf). Through the observation of fracture surface and cross-section microstructure, the increase of joint strength resulted from the change of fracture mode, that is, from the solder ball fracture to IMC/Ni(P) interfacial fracture. The other cases like radical treated specimen for 1, 3, 7, 9min. showed IMC/solder interfacial fracture rather than fracture in the solder ball.