• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.198-198
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• 2011

Organocatalysis is a relatively new and popular area within the field of chiral molecule synthesis. It is one of the main branches of enantioselective synthesis with enzymatic and organometallic catalysis. In recent years, immense high quality studies on catalysis by chiral secondary amines were reported. These progresses instantly led to different organocatalytic activation concepts, so thousands of researchers from academia and the chemical industry are currently involved in this field and new ideas, new approaches, and creative thinking have been rapidly emerged. Organocatalysts, some of which are natural products, appear to solve the problems of metal catalysts. Compared to metal-based catalysis, they have many advantages including savings in cost, time, and energy, easier experimental procedure, and reduction of chemical waste. These benefits originate from the following factors. First, organocatalysts are generally stable in oxygen and water in the atmosphere, there is no need for special equipments or experimental techniques to operate under anhydrous or anaerobic conditions. Second, organic reagents are naturally available from biological materials as single enantiomers that they are easy and cheap to prepare which makes them suitable for small-scale to industrial-scale reactions. Third, in terms of safety related catalysis, small organic molecules are non-toxic and environmentally friendly. Therefore, the purpose of this research is to develop novel synthetic methods and design for various organocatalyst. Furthermore, it is expected that these organocatalysts can be applied to a variety of asymmetric reactions and study the transition state of these reactions using a metal sulface. Here, we report the synthesis of unprecedented organocatalysts, proline and pyrrolidine derivatives with quaternary carbon center.

• 한국식품과학회지
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• 제45권5호
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• pp.628-635
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• 2013

본 연구는 복분자 미숙과와 홍삼 물 추출물을 이용하여 인간 간암세포주(HepG2)와 위장관세포주(Caco-2)를 이용하여 콜레스테롤 억제효과 및 그와 연관된 HMG-CoA reductase 활성 억제효과 및 LDL 및 HDL과 관련된 분자기전을 조사하였다. 그 결과 복분자 미숙과와 홍삼 추출물은 모두 콜레스테롤 합성 억제 효과를 보였을 뿐만 아니라 HMG-CoA reductase 활성 억제효과를 보였다. 또한 두 추출물은 단독 투여시 보다 복합 투여시 부가효과를 보였다. 그리고 LDL receptor와 이를 조절하는 SREBP-2를 증가시키고 콜레스테롤 transport 인 ABCA1의 발현을 증가시켜 LDL를 낮추고 HDL를 높이는 효과가 있을 것으로 판단된다. 특히 두 추출물의 복합 투여시 훨씬 높은 시너지 효과를 나타냄을 확인하였다. 이러한 결과는 전통적으로 오랜 기간 사용되어온 천연물인 복분자와 홍삼이 콜레스테롤 예방에 효과적임을 입증한 결과로 관련 대사증후군의 예방에 기여할 것으로 사료된다.

• 한국결정성장학회지
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• 제24권1호
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• pp.1-7
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• 2014

질화알루미늄(AlN)은 뛰어난 열적, 전기절연성 특성을 갖고 있어 반도체 기판용 재료나 전자 패키징 재료로 주목받고 있다. 질화알루미늄은 소결온도가 높고 불순물로 인한 물성저하 때문에 고순도화 및 나노원료화가 필수적이다. 본 연구에서는 RF 유도결합 열플라즈마를 이용하여 알루미늄 분말로부터 고순도의 질화알루미늄 나노분말을 합성하였다. Sheath gas로 사용된 암모니아의 유량 제어를 통해 고순도의 질화알루미늄 나노분말이 합성되는 조건을 확립하고자 하였으며 합성된 분말은 XRD, SEM, TEM, BET, FTIR, N-O분석을 통해 특성분석을 진행하였다.

• Journal of Nutrition and Health
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• 제31권1호
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• pp.21-27
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• 1998

The objective of this study was to observe the effect of dietary calcium(Ca) level on colonic mucosal levels of cell proliferation, 1, 2-diacylglycerol(DAG), TXB2, PGE2 and phospholipid fatty acid composition which have been known as biomarkers for colon cancer. One hundred male Sprague Dawley rats, at 7 weeks of age, were divided into two fat type groups. Each group of which was further divided into two Ca level groups. Each rt was intramuscularly injected with 1, 2,-dimenthylhydrazine(DMH) for 6 weeks (total dose of 180mg/kg body weight) and simultaneously fed one of four experimental diets containing 15% dietary fat(corn oil or perilla oil )and 0.3% or 1.0% Ca by weight for 20 weeks. Compared to corn oil, perilla oil significantly reduced cell proliferation by decreasing labeling index, proliferating zone, crypt length in colonic mucosa and colonic mucosa and colonic mucosal levels of DAG, TXB2 . PGE2 and phospolipid (PL) arachidonic acid distribution. The effect of Ca on biomarketrs was different depending on the type of dietary fat comsumed . Ca effect of Ca on biomarkers was different depending on the type of dietary fat comsumed. Ca effect was not significantly shown in the PO group, but it was significant in the CO group in which high Ca(1.0%) decreased the levels of levels of PL-C20 : 4(%), DAG and PGE2 . However , high Ca supplementation had shown only the trends of improving cell proliferation. Overall , high dietary Ca significantly reduced cell proliferation by inhibiting the synthesis of eicosanoid and DAG with reduced distribution of PL-C20 : 4 , which may have resulted in lower activation of PKC through reduced signal transduction. Since a high level of dietary Ca was more effective in reducing the risk factor against colon cancer in corn oil fed rats, it could be suggested that a higher amount of dietary Ca be consumed , especially when more vegetable oil rich in linoleic acid is included in the diet.

• 생명과학회지
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• 제17권11호
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• pp.1492-1496
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• 2007

CD40L를 발현하는 KU812세포와 CD40를 발현하는 항원 특이적 B 세포의 배양을 통해 IgE 클라스 스위치가 유도된다. 본 연구자는 체외면역법에 의해 건강인의 말초혈액을 이용하여 쌀 알레르겐 특이적 IgM 항체를 생성하는 B 세포주를 수립하였다. 본 연구에서는 KU812세포에 의한 쌀 알레르겐 특이적 IgE 항체의 유도를 시도하였다. 배양 전, 쌀 알레르겐 특이적 B 세포주, RA9G11과 PMA와 ionomycin을 6시간 처리하여 활성화된 KU812세포에서 CD40와 CD40L 발현량을 flow cytomerty를 통화여 각각 확인하였다. RA9G11세포와 활성화된 KU812세포는 높은 수준의 CD40와 CD40L를 각각 발현하였다. 쌀 알레르겐 특이적 IgE항체 합성 유도를 위해, 여러 가지 농도의 IL-4 존재하에, RA9G11세포와 활성화된 KU812세포를 12일 동안 배양하였다. IgE 정상영역의 mRNA 발현량과, 쌀 알레르겐 특이적 IgE 항체 생성 세포가 모든 조건에서 확인되었으며, 특히 50U의 L-4 농도 하에서 같은 비율의 RA9G11과 활성화된 KU812세포를 배양했을 때, IgE 합성이 가장 높았다. 따라서 활성화된 KU812세포에 의한 쌀 알레르겐 특이적 IgE 합성은 알레르기 질환의 치료 및 예방에 관한 연구에 기여할 것으로 사료된다.

• 한국토양비료학회지
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• 제49권2호
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• pp.168-180
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• 2016

Various researches on the effects of fertilization levels on functional metabolites in crop have been conducted. This review summarizes the previous studies on the relation between fertilization supply and accumulation of metabolites (phenolics, carotenoids, ascorbic acid and glucosinolates) which function as antioxidants in crop. The accumulation of phenolic compounds is related to the activation of phenylalanine ammonia lyase (PAL) in phenylpropanoid pathway. Most of the previous studies discuss that low nitrogen (N) supply activates PAL, thereby increasing the synthesis of phenolics. Similarly, high N supply leads to a decrease in ascorbic acid because of the shading effect derived from the accelerated vegetative growth under high N level. Unlike the phenolics and ascorbic acid, carotenoids are accumulated with increasing N supply. In this regard, the previous studies explain that N is a main element closely associated with formation of key enzyme for the synthesis of carotenoids. Glucosinolates are generally increased under decreasing N supply and increasing S supply. Although the previous studies show similar trends about the accumulation of metabolites by nutrient level, they also suggest that many other factors including crop types, cultivars, cultural environment (water, temperature, light, etc.) influence the accumulation of functional metabolites in crop.

• 자원환경지질
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• 제39권2호
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• pp.173-180
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• 2006

석류석과 스피넬의 혼합성분$(Gd_3Fe_5O_{12}+(Ni_xMn_{1-x})(Fe_yCr_{1-y})_2O_4)$으로부터 고준위 방사성 폐기물의 고정화를 위한 다상 고화체를 $1200{\sim}1400^{\circ}C$에서 합성하였다. 이들 화학조성에서는 석류석, 페롭스카이트 및 스피넬이 관찰되었으며, 특히 석류석은 Fe의 함량이 가장 높았던 조성에서만 관찰되는 특성을 보임으로써 Fe의 함량이 석류석의 형성과 밀접한 관계를 지시하고 있다. 석류석의 성분은 Gd와 Fe가 각각 초과 및 결핍된 양상을 보였다. 이같은 석류석의 비화학 양론적인 조성은 상들과 원소간의 선호적 배분관계에 기인된 것으로 사료된다.

• Toxicological Research
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• 제12권2호
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• pp.213-221
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• 1996

In order to develop a suitable secondary renal disease model and diagnostic markers of renal disease in the rat, the change of PIIIP (aminoterminal procollagen III peptide) in serum and hydroxyproline levels in the renal tissue that reflect the synthesis of extracellular matrix (ECM) during development of experimental renal diseases were observed. Two types of experimental primary diseases, diabetes mellitus administrated by streptozotocin (STZ, 75 mg/kg, i.p.) and liver cirrhosis produced by bile duct ligation/scission (BDL/s) operation, were induced. The hydroxyproline level increased according to the high PIIIP and NCl(carboxyterminal procollagen IV peptide) in Western blot analysis as early as 1 week in the STZ treated-rat kidney. Increased renal ECM was observed at 15 weeks in STZ and BDL/s model under the microscopic examination. High PAS positive reaction was found in capillary basement membrane in STZ treated-rats and mesangium in BDL/s operated rats at this time, showing the histological characteristics of diabetic nephropathy and cirrhotic glomerulonephritis in human, respectively. Such secondary renal failure were supported by additional tests including urinalysis and renal function test. The serum PIIIP detected by ELISA was a useful parameter to estimate synthesis rate of renal ECM during development of renal disease without extrarenal fibrosis i.e. liver cirrhosis in rats. This study is proposed that STZ treatment or BDL/s operation may be a suitable experimental animal model for the induction and development of chronic secondary renal diseases. Morover, it was found that hydroxyproline level in renal tissues was a good parameter of the change of renal ECM at the early stage of the diseases without apparent histological changes. Especially, serum PIIIP could be a choice as a diagnostic or prognostic marker during the development of renal diseases in rats.

• 시스템엔지니어링학술지
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• 제11권2호
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• pp.61-73
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• 2015

The early-phase naval ship design demands requirements synthesis rather than design synthesis, which conducts engineering design for several domains on a detailed level. Requirements synthesis focuses on creating a balanced set of required operational capabilities satisfying user's needs and concept of operations. Requirements are evolved from capability based languages to function based language by statistical exploration and engineering design which are derived in the following order: concept alternative, concept baseline, initial baseline and functional baseline. The early-phase naval ship design process can be divided into three passes: concept definition, concept exploration and concept development. Main activities and outcomes in each pass are shortly presented. Concept definition is the first important step that produces a concept baseline through extensive design space exploration promptly. Design space exploration applies a statistical approach to explore design trends of existing ships and produce feasible design range corresponding to concept alternative. It further helps naval systems engineers and operational researchers by inducing useful responses to user and stakeholders' questions at a sufficient degree of confidence and success in the very early ship design. The focus of this paper is on the flow of design space exploration, and its application to a high-speed patrol craft. The views expressed in this paper are those of the authors, and do not reflect the official policy or rule of the Navy.

• 한국초지조사료학회지
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• 제42권3호
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• pp.201-207
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• 2022

Fescues, which are widely cultivated as grasses and forages around the world, are often naturally infected with the endophyte, Epichloë. This fungus, transmitted through seeds, imparts resistance to drying and herbivorous insects in its host without causing any external damage, thereby contributing to the adaptation of the host to the environment and maintaining a symbiosis. However, some endophytes, such as E. coenophialum synthesize ergovaline or lolitrem B, which accumulate in the plant and impart anti-mammalian properties. For example, when livestock consume excessive amounts of grass containing toxic endophytes, problems associated with neuromuscular abnormalities, such as convulsions, paralysis, high fever, decreased milk production, reproductive disorders, and even death, can occur. Therefore, pre-inoculation with non-toxic endogenous fungi or management with endophyte-free grass is important in preventing damage to livestock and producing high-quality forage. To date, the diagnosis of endophytes has been mainly performed by observation under a microscope following staining, or by performing an immune blot assay using a monoclonal antibody. Recently, the polymerase chain reaction (PCR)-based molecular diagnostic method is gaining importance in the fields of agriculture, livestock, and healthcare given the method's advantages. These include faster results, with greater accuracy and sensitivity than those obtained using conventional diagnostic methods. For the diagnosis of endophytes, the nested PCR method is the only available option developed; however, it is limited by the fact that the level of toxic alkaloid synthesis cannot be estimated. Therefore, in this study, we aimed to develop a triplex real-time PCR diagnostic method that can determine the presence or absence of endophyte infection using DNA extracted from seeds within 1 h, while simultaneously detecting easD and LtmC genes, which are related to toxic alkaloid synthesis. This new method was then also applied to real field samples.