1,708 research outputs found

    Development of KAISTSAT-4 Expanding the Role of Small Satellite for Scientific Research

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    The fourth Korean small satellite, KAISTSAT-4, is under development by Satellite Technology Research Center (SaTReC) of the Korea Advanced Institute of Science and Technology (KAIST). The KAISTSAT-4 program was commenced on October 1998 with multiple mission objectives, which include exploring space science, deploying satellite-based data collection system and development of precision star sensor. Despite severe constraints on mass and size, these advanced science and engineering payloads are expected to deliver various useful results and exhibit the unique role of small satellite. We present an overview of the KAISTSAT-4 mission and describe its current status. Finally the prospect of future small satellite programs is briefly introduced

    Nitrogen Budget of South Korea from 2015 to 2019 Including Gaseous Nitrogen Oxides

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    Objectives The study was aimed to systematically understand the nitrogen budget from 2015 to 2019, and to determine the annual nitrogen balance in South Korea. Methods The nitrogen budget was calculated by classifying into agricultural and livestock, city, and forest areas. The nitrogen input was estimated from deposition, biological fixation, agricultural water, inorganic chemical fertilizer, compost, feedstuff, produced crops, imported grocery, and fuel consumption. The nitrogen output was estimated by considering denitrification, volatilization, ground water runoff, land and crop absorption, sewage disposal, drainage, forest uptake, and nitrogen oxide (NOx) emissions. Results and Discussion The annual nitrogen budget from 2015 to 2019 showed the input as 6,107,449 ton/yr, 6,144,666 ton/yr, 6,245,240 ton/yr, 6,281,552 ton/yr, 5,993,347 ton/yr and the output as 1,346,587 ton/yr, 1,369,119 ton/yr, 1,365,327 ton/yr, 1,378,940 ton/yr, 1,365,994 ton/yr, respectively. The NOx, highly contributing to change in the nitrogen budget, was caused by human activities such as vehicles, business places, and power plants. More than 32% of the total nitrogen budget was caused by NOx in every year. Conclusion The nitrogen budget continued to increase in the 2010s because of the increase in food and fuel consumption by urbanization. However, the nitrogen budget declined in 2019 due to the effort such as emission regulations and the use of alternatives as the awareness of environmental pollution gradually increased. Therefore, the appropriate institution should be established and actively implemented to reduce the nitrogen effectively

    Automatic Segmentation of Brachial Artery based on Fuzzy C-Means Pixel Clustering from Ultrasound Images

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    Automatic extraction of brachial artery and measuring associated indices such as flow-mediated dilatation and Intima-media thickness are important for early detection of cardiovascular disease and other vascular endothelial malfunctions. In this paper, we propose the basic but important component of such decision-assisting medical software development – noise tolerant fully automatic segmentation of brachial artery from ultrasound images. Pixel clustering with Fuzzy C-Means algorithm in the quantization process is the key component of that segmentation with various image processing algorithms involved. This algorithm could be an alternative choice of segmentation process that can replace speckle noise-suffering edge detection procedures in this application domain

    A Surgically Treated Case of Chronic Necrotizing Aspergillosis with Pleural Invasion

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    Aspergillus is a ubiquitous fungus and can cause many levels of disease severity. Chronic necrotizing aspergillosis is a rare disease and few cases have been reported in Korea. We experienced a case of pleural aspergillosis that was treated successfully with medical and surgical interventions. The 52-year-old man who was diagnosed with chronic necrotizing pulmonary aspergillosis underwent surgical treatment including a lobectomy, decortication, and myoplasty. The patient was also medically treated with amphotericin B followed by voriconazole. Pleural irrigation with amphotericin B was also performed. A multi-dimensional approach should be considered for treating chronic necrotizing pulmonary aspergillosis

    Influenza Vaccination and Associated Factors among Korean Cancer Survivors : A Cross-Sectional Analysis of the Fourth Fifth Korea National Health and Nutrition Examination Surveys

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    Influenza vaccination is important for cancer survivors, a population with impaired immunity. This study was designed to assess influenza vaccination patterns among Korean cancer survivors. In this cross-sectional analysis, data were obtained from standardized questionnaires from 943 cancer survivors and 41,233 non-cancer survivors who participated in the Fourth and Fifth Korea National Health and Nutrition Examination Surveys (2007-2011). We identified the adjusted influenza vaccination rates and assessed factors associated with influenza vaccination using multivariate logistic regression. Cancer survivors tended to have a higher adjusted influenza vaccination rate than the general population. The rates for influenza vaccination in specific cancer types such as stomach, hepatic, colon, and lung cancers were significantly higher than non-cancer survivors. Among all cancer survivors, those with chronic diseases, elderly subjects, and rural dwellers were more likely to receive influenza vaccination; those with cervical cancer were less likely to receive influenza vaccination. Cancer survivors were more likely to receive influenza vaccinations than non-cancer survivors, but this was not true for particular groups, especially younger cancer survivors. Cancer survivors represent a sharply growing population; therefore, immunization against influenza among cancer survivors should be concerned as their significant preventative healthcare services.OAIID:oai:osos.snu.ac.kr:snu2014-01/102/0000052039/13SEQ:13PERF_CD:SNU2014-01EVAL_ITEM_CD:102USER_ID:0000052039ADJUST_YN:YEMP_ID:A079543DEPT_CD:806CITE_RATE:1.253FILENAME:influenza vaccination and associated factors among korean cancer survivors, a cross-sectional analysis of the fourth ~.pdfDEPT_NM:의과학과SCOPUS_YN:YCONFIRM:

    Facile synthesis of nano-Li4 Ti5O12 for high-rate Li-ion battery anodes

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    One of the most promising anode materials for Li-ion batteries, Li4Ti5O12, has attracted attention because it is a zero-strain Li insertion host having a stable insertion potential. In this study, we suggest two different synthetic processes to prepare Li4Ti5O12 using anatase TiO2 nanoprecursors. TiO2 powders, which have extraordinarily large surface areas of more than 250 m2 g-1, were initially prepared through the urea-forced hydrolysis/precipitation route below 100°C. For the synthesis of Li4Ti5O12, LiOH and Li2CO3 were added to TiO2 solutions prepared in water and ethanol media, respectively. The powders were subsequently dried and calcined at various temperatures. The phase and morphological transitions from TiO2 to Li4Ti5O12 were characterized using X-ray powder diffraction and transmission electron microscopy. The electrochemical performance of nanosized Li4Ti5O12 was evaluated in detail by cyclic voltammetry and galvanostatic cycling. Furthermore, the high-rate performance and long-term cycle stability of Li4Ti5O12 anodes for use in Li-ion batteries were discussed

    Crystallization and preliminary X-ray crystallographic studies of the ice-binding protein from the Antarctic yeast Leucosporidium sp. AY30. Corrigendum

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    A correction to the article by Park et al. [(2011). Acta Cryst. F67, 800–802]

    Psychobiotics and fecal microbial transplantation for autism and attention-deficit/hyperactivity disorder: microbiome modulation and therapeutic mechanisms

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    Dysbiosis of the gut microbiome is thought to be the developmental origins of the host’s health and disease through the microbiota-gut-brain (MGB) axis: such as immune-mediated, metabolic, neurodegenerative, and neurodevelopmental diseases. Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are common neurodevelopmental disorders, and growing evidence indicates the contribution of the gut microbiome changes and imbalances to these conditions, pointing to the importance of considering the MGB axis in their treatment. This review summarizes the general knowledge of gut microbial colonization and development in early life and its role in the pathogenesis of ASD/ADHD, highlighting a promising therapeutic approach for ASD/ADHD through modulation of the gut microbiome using psychobiotics (probiotics that positively affect neurological function and can be applied for the treatment of psychiatric diseases) and fecal microbial transplantation (FMT)
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