• Journal of Microbiology
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• 제45권5호
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• pp.409-417
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• 2007

Burkholderia sp. HY-10 isolated from the digestive tracts of the longicorn beetle, Prionus insularis, produced an extracellular lipase with a molecular weight of 33.5 kDa estimated by SDS-PAGE. The lipase was purified from the culture supernatant to near electrophoretic homogenity by a one-step adsorption-desorption procedure using a polypropylene matrix followed by a concentration step. The purified lipase exhibited highest activities at pH 8.5 and $60^{\circ}C$. A broad range of lipase substrates, from $C_4\;to\;C_{18}$ p-nitrophenyl esters, were hydrolyzed efficiently by the lipase. The most efficient substrate was p-nitrophenyl caproate ($C_6$). A 2485 bp DNA fragment was isolated by PCR amplification and chromosomal walking which encoded two polypeptides of 364 and 346 amino acids, identified as a lipase and a lipase foldase, respectively. The N-terminal amino acid sequence of the purified lipase and nucleotide sequence analysis predicted that the precursor lipase was proteolytically modified through the secretion step and produced a catalytically active 33.5 kDa protein. The deduced amino acid sequence for the lipase shared extensive similarity with those of the lipase family 1.2 of lipases from other bacteria. The deduced amino acid sequence contained two Cystein residues forming a disulfide bond in the molecule and three, well-conserved amino acid residues, $Ser^{131},\;His^{330},\;and\;Asp^{308}$, which composed the catalytic triad of the enzyme.

• Ocean and Polar Research
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• 제42권1호
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• pp.77-88
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• 2020

This paper presents the coordinate systems used for trawl doors modeling, and provides matrix equations of connection between these systems. The projections of the forces acting on the door into axes of various coordinate systems were obtained, which were used in the door equilibrium equations. Six equilibrium conditions for the door as a solid were obtained: formulas that allow for the door area in plan to be determined; its weight in water; its mass; three moment equations for determining the position of the warp and backstrops fastening points to the door with triangular and quadrangular backstrop arrangements. It was found that the moment equilibrium equations of trawl doors are generally incompatible, which was not found by any of the authors who have previously conducted research into trawl doors. Using the Kronecker-Capelli theorem, the compatibility equation is obtained. This equation includes the coordinates of the backstrop fastening points to the door, which means that these points cannot be randomly selected. The technique of determining the warp and backstrops' fastening points position to the door is described. Conditions of directional (by angle of attack) and roll (in angle of roll) stability of the doors' equilibrium are presented. The equations presented in this paper comprise a mathematical model that allows, when designing the doors, to select optimal parameters, as well as to carry out adjustments for trawling purposes to ensure the stable movement of the doors and the entire trawl system.

• 한국콘텐츠학회논문지
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• 제18권1호
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• pp.64-75
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• 2018

위치 인식 기술의 발전 및 스마트 디바이스 사용의 활성화로 인해 위치 기반 서비스과 소셜 네트워크를 결합하여 사용자에게 정보를 공유하는 위치 기반 소셜 네트워크(LBSN: Location Based Social Network)이 활성화되고 있다. 위치 기반 소셜 네트워크에서 사용자의 체크인 기능을 이용하여 사용자가 가 흥미있어 할 만한 장소를 추천하는 연구가 활발히 이루어지고 있다. 본 논문은 위치기반 소셜 네트워크에서 시간과 사용자 활동을 고려한 장소 추천 기법을 제안한다. 제안하는 기법은 기존 논문에서 고려하지 못한 시간에 따른 사용자의 선호도 변화와 지역의 전문가, 희귀한 장소에 대한 사용자의 관심을 고려한다. 다시 말해, 사용자의 선호도 변화를 고려하기 위해 시간에 따른 체크인 이력을 사용하고 지역의 전문가를 판별하기 위해 사용자 활동 영역을 구분한다. 그리고 사용자가 선호하는 장소에 가중치를 주기 위하여 희귀한 장소를 고려한다. 다양한 성능평가를 통해 제안하는 기법이 기존 기법에 비해 성능이 우수함을 보인다.

• 기술혁신학회지
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• 제14권1호
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• pp.60-84
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• 2011

본 연구에서는 연구개발 사업에서 기술가치평가의 중요성 및 필요성을 인식하며, ANP(Analytic Network Process)기법을 적용하여 연구개발 사업으로 추진되고 있는 가스하이드레이트 개발 사업의 기술향상도를 평가하였다. ANP 방법은 요인들간의 상호 종속성 및 네트워크를 고려하여 연구개발 사업을 통해 개발된 기술의 가치를 평가 할 수 있다는 장점이 있다. 가스하이드레이트 개발사업의 기술향상도 평가를 위하여 사업의 4개 기술 분야 별 전문가의 자문 및 설문 결과를 바탕으로 기술향상도에 영향을 미치는 속성을 선정하였고, 각 속성 및 대안의 상호 종속성 관계를 고려한 네트워크 구조도를 도출하였다. ANP 기법을 적용하여 가중치 행렬을 도출한 결과 네트워크 구조도에서 보여지는 상호 관계를 확인할 수 있었다. 이러한 속성간 네트워크 관계는 기술가치평가에서 ANP 방법의 적용의 당위성을 제공해 준다. 기술향상도를 나타내는 요인의 극한 가중치 도출 결과에서는 모든 기술에서 실현 가능성이 가장 높게 평가되었다. 1위 이외에 다른 속성의 순위 및 기술향상도의 평가에서는 사업 수행 전 기술의 수준에 따라 영향을 받는 것으로 분석되었다.

• 한국식품영양과학회지
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• 제44권11호
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• pp.1645-1652
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• 2015

해양생물 유래 피부건강 기능성의 소재를 발굴할 목적으로 굴 단백질을 Protamex와 Neutrase로 가수분해 한 후 생성된 굴 가수분해물 펩타이드의 주름 개선 효과를 조사하였다. 굴 가수분해물은 약 7.9%의 유리아미노산을 포함하며 urea, taurine, alanine, glycine 등의 아미노산의 함량이 높았다. 굴 가수분해물은 collagenase 저해 활성을 가지고 있었고, 피부세포인 CCD986sk에 대한 독성은 없었다. 분획물의 수율은 1,000 Da 미만이 40%였으며, 5,000 Da 미만이 60.4%를 차지하였다. 1,000~3,000 Da인 분획물이 항산화 활성, procollagen의 생성능 및 MMP-1 효소 저해 활성이 가장 높았다. 굴 가수분해물과 5,000 Da 미만의 분획물은 주름 개선을 위한 피부건강 기능성 소재로서 화장품 등의 제품에 응용 가능함을 확인하였다.

• 한국자원식물학회지
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• 제33권6호
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• pp.638-644
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• 2020

Lilium lancifolium (LL) is widely cultivated in East Asia and used to attenuate airway diseases. Our current study aimed to investigate the therapeutic effect of LL on pain level and inflammatory response in a rat model of monosodium iodoacetate (MIA)-induced osteoarthritis (OA). We first examined the effect of LL on inflammatory cytokines and inflammatory mediators in IL-1β-treated HTB-94 cells. The LL extract was found to significantly inhibit the levels of Interleukin-6 (IL-6), Interleukin-8 (IL-8), and prostaglandin-E2 (PGE-2) in Interleukin-1 β (IL-1β)-stimulated HTB-94 cells in a dose-dependent manner. Moreover, chronic oral administration of LL effectively restored the weight-bearing distribution in the rat model of MIA-induced OA. In addition, administration of LL inhibited inflammatory cytokines and inflammatory mediators, such as C-reactive protein (CRP), IL-6, leukotriene B4 (LTB-4), PGE-2, and matrix metalloproteinase-9 (MMP-9). Our findings collectively suggested LL as one of the potential therapeutic agents for OA, owing to its properties of reducing pain and inflammatory responses.

• Archives of Pharmacal Research
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• 제26권1호
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• pp.76-82
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• 2003

Drug releasing porous poly($\varepsilon$-caprolactone) (PCL)-chitosan matrices were fabricated for bone regenerative therapy. Porous matrices made of biodegradable polymers have been playing a crucial role as bone substitutes and as tissue-engineered scaffolds in bone regenerative therapy. The matrices provided mechanical support for the developing tissue and enhanced tissue formation by releasing active agent in controlled manner. Chitosan was employed to enhance hydrophilicity and biocompatibility of the PCL matrices. PDGF-BB was incorporated into PCL-chitosan matrices to induce enhanced bone regeneration efficacy. PCL-chitosan matrices retained a porous structure with a 100-200 $\mu$m pore diameter that was suitable for cellular migration and osteoid ingrowth. $NaHCO_3$ as a porogen was incorporated 5% ratio to polymer weight to form highly porous scaffolds. PDGF-BB was released from PCL-chitosan matrices maintaining therapeutic concentration for 4 week. High osteoblasts attachment level and proliferation was observed from PCL-chitosan matrices. Scanning electron microscopic examination indicated that cultured osteoblasts showed round form and spread pseudopods after 1 day and showed broad cytoplasmic extension after 14 days. PCL-chitosan matrices promoted bone regeneration and PDGF-BB loaded matrices obtained enhanced bone formation in rat calvarial defect. These results suggested that the PDGF-BB releasing PCL-chitosan porous matrices may be potentially used as tissue engineering scaffolds or bone substitutes with high bone regenerative efficacy.

• 한국인터넷방송통신학회논문지
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• 제15권3호
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• pp.149-154
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• 2015

본 논문은 안정된 결혼문제의 최적해를 쉽고 빠르게 찾는 알고리즘을 제안하였다. 첫 번째로, 남성의 여성 선호도와 여성의 남성 선호도 합 $p_{ij}$의 $n{\times}n$ 정방행렬로 변환시킨다. 두 번째로, 행렬에서 최대 반감도 (최악의 선호도)인 최대값 $_{max}p_{ij}$를 행 또는 열의 개수가 1개 ($|r_i|=1$ or $|c_j|=1$)가 존재할 때까지 삭제한다. 만약, $|r_i|=1$ or $|c_j|=1$이면 선택하고, 선택된 $p_{ij}$의 행 또는 열 값을 삭제한다. 이 과정을 ${\forall}(|r_i|=1{\cap}|c_j|=1)$가 될 때까지 반복 수행한다. 제안된 알고리즘을 7개의 안정된 결혼문제에 적용한 결과 간단하면서도 기존 알고리즘의 해를 개선하는 효과를 얻었다.

• Bulletin of the Korean Chemical Society
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• 제32권3호
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• pp.867-872
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• 2011

For the prolonged delivery and sustained release rates of low molecular weight drugs, poly(lactic-co-glycolic acid) (PLGA) microparticles containing the drug SKL-2020 have been investigated. On increasing polyvinyl alcohol (PVA) concentration (from 0.2% to 5%), the size of microparticles decreased (from $48.02{\mu}m$ to $10.63{\mu}m$) and more uniform size distribution was noticeable due to the powerful emulsifying ability of PVA. A higher drug loading (from 5% to 20%) caused a larger concentration gradient between 2 phases at the polymer precipitation step; this resulted in decreased encapsulation efficiency (from 34.19% to 25.67%) and a greater initial burst (from 61.71% to 70.05%). SKL-2020-loaded PLGA microparticles prepared with different fabrication conditions exhibited unique release patterns of SKL-2020. High PVA concentration and high drug loading led to an initial burst effect by rapid drug diffusion through the polymer matrix. Since PLGA microparticles enabled the slow release of SKL-2020 over 1 week in vitro and in vivo, more convenient and comfortable treatment could be facilitated with less frequent administration. It is feasible to design a release profile by mixing microparticles that were prepared with different fabrication conditions. By this method, the initial burst could be repressed properly and drug release rate could decrease.

• 한국동물위생학회지
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• 제37권1호
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• pp.79-84
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• 2014

Two Hahns Macaws (Ara nobilis nobilis), three and nine-month-old, with a three-weeks history of weight loss and anorexia were diagnosed presumptively with proventricular dilatation disease (PDD) by radiographic examination. The birds were treated with antimicrobials, analgesics, and fluid administration. However, these birds died three weeks after the first signs of PDD. At necropsy, the birds had severely dilated proventriculus, severe pectoral muscles atrophy, and blood vessels congestion on cortex of cerebrum. The partial matrix gene of avian bornavirus (ABV) was detected by RT-PCR from tissues of the brain, feather calami, and proventiculus of each PDD-suspected birds. This report describes the first detection of ABV in PDD-suspected Hahns Macaw in Korea.