• 제목/요약/키워드: Chang-rae Lee

검색결과 409건 처리시간 0.025초

대한해협 부유성 요각류의 계절별 수직분포 (Seasonal and Vertical Distribution of Planktonic Copepods in the Korea Strait)

  • 이창래;이평강;박철
    • 한국수산과학회지
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    • 제32권4호
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    • pp.525-533
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    • 1999
  • 사계절 수층별 채집에서 요각류는 총 40속 96개 분류군이 동정되었다. 가을철에 가장 많은 종류가 대마난류를 통해 동해로 유입되고 있었다. 정점별로는 모든 계절에서 유의적인 차이를 보이지 않았다 (ANOVA, p>0.05) 각 계절의 수심별 비교에서는 여름철과 겨울철에 중 저층에서 다소 많은 분류군이 동정되었다. 요각류의 총 개체수는 종수와는 달리 봄철에 가장 많은 163.8 개체/$m^3$가 분포하였다. 가장 풍부했던 봄철에는 저층 부근에서 높은 개체수를 보였으며, 여름철과 가을철에는 저층보다는 표충에서 가장 높은 개체수를 보였다. 집괴분석을 통하여 종간 유연관계를 파악한 결과, 대한해협에 출현하는 요각류는 공동출현과 배타적 출현 의 두 그룹이 분명하였다. 각 그룹은 계절변화에 따라 수층별 분포양상이 달랐다. 동해 냉수가 대한해협 저층에 유입되는 계절에 대하여 물리적 자료를 바탕으로 서로 다른 결과가 있는데 [여름(Cho and Kim, 1998)과 겨울철 (Lee et al., 1998)], 요각류 분포 자료를 바탕으로한 이 연구에서는 여름철에 두드러지는 것으로 나타났다. 서해나 남해에 비하여 상대적으로 작은 변화를 보이는 수온 구조이지만 여전히 수온이 부유성 요각류의 분포에 상대적으로 큰 영향을 미치고 있으며, 서식처의 공동 혹은 배타적 이용과 같은 생물학적 상호관계 역시 분포에 큰 영향을 미치고 있는 것으로 판단되었다.

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O/W 용매 증발법을 이용한 PLGA와 덱스트란의 이중층 미립구 제조 (Fabrication of PLGA/Dextran Double-Layered Microspheres by Oil-in-Water Solvent Evaporation Method)

  • 고종태;이재호;이창래;신형식;육순홍;김문석;강길선;이종문;이해방
    • 폴리머
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    • 제29권6호
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    • pp.543-548
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    • 2005
  • 이중층 미립구는 단일층 미립구에 비해서 낮은 초기 방출량과 국소 지항성, 및 약물 방출량 제어 등의 장점 을 갖고 있다. 그러나 포접 방식이 까다롭고 2단계 이상의 제조 과정이 필요하며 특히 미립구 제조 시 크기 조절이 어렵다는 단점을 갖고 있다. 따라서 본 연구에서는 락타이드글리콜라이드 공중합체(PLGA)와 덱스트란의 서로 다른 고분자를 초고주파 분쇄 유무에 따른 수중유형(O/W) 용매 증발법을 이용하여 이중층 미립구를 제조하였다. 또한 PLGA의 농도에 따라 미립구 크기의 변화를 연구하였다. 이중층 미립구는 전자주사현미경, 동초점 형광 레이저현미경(CFLM), 캠스코프를 이용하여 조사하였다. 제조된 이중층 미립구의 외부층이 매끄러운 구형의 형태를 나타냄을 확인할 수 있었으며, 절단시 내부층과 외부층의 형태를 확실히 구분할 수 있었다. 이에 외부층과 내부층의 구성 물질을 확인하고자 플루오르신-5-이소시아네이트-덱스트란(FITC-덱스트란)을 이용해 CFLM을 관찰한 결과 형광을 띠는 덱스트란으로 구성된 내부층과 형광을 띠지 않는 PLGA 외부층을 관찰하였다. 또한 PLGA의 함량에 따른 미립구의 크기는 전체적으로 증가하는 경향을 확인하였다. 이와 같은 결과로부터 비교적 간단한 수중유형 용매 증발법을 이용하여 PLGA와 덱스트란의 이중층 미립구의 제조가 가능함을 확인할 수 있었다.

Characterization of Recombinant Bovine Sperm Hyaluronidase and Identification of an Important Asn-X-Ser/Thr Motif for Its Activity

  • Park, Chaeri;Kim, Young-Hyun;Lee, Sang-Rae;Park, Soojin;Jung, Yena;Lee, Youngjeon;Kim, Ji-Su;Eom, Taekil;Kim, Ju-Sung;Lee, Dong-Mok;Song, Bong-Suk;Sim, Bo-Woong;Kim, Sun-Uk;Chang, Kyu-Tae;Kim, Ekyune
    • Journal of Microbiology and Biotechnology
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    • 제28권9호
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    • pp.1547-1553
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    • 2018
  • Hyaluronidases are a family of enzymes that catalyse the breakdown of hyaluronic acid, which is abundant in the extracellular matrix and cumulus oocyte complex. To investigate the activity of recombinant bovine sperm hyaluronidase 1 (SPAM1) and determine the effect of the Asn-X-Ser/Thr motif on its activity, the bovine SPAM1 open reading frame was cloned into the mammalian expression vector pCXN2 and then transfected to the HEK293 cell line. Expression of recombinant bovine hyaluronidase was estimated using a hyaluronidase activity assay with gel electrophoresis. Recombinant hyaluronidase could resolve highly polymeric hyaluronic acid and also caused dispersal of the cumulus cell layer. Comparative analysis with respect to enzyme activity was carried out for the glycosylated and deglycosylated bovine sperm hyaluronidase by N-glycosidase F treatment. Finally, mutagenesis analysis revealed that among the five potential N-linked glycosylation sites, only three contributed to significant inhibition of hyaluronic activity. Recombinant bovine SPAM1 has hyaluronan degradation and cumulus oocyte complex dispersion ability, and the N-linked oligosaccharides are important for enzyme activity, providing a foundation for the commercialization of hyaluronidase.

계량정보분석시스템으로서의 KnowledgeMatrix 개발 (Development of the KnowledgeMatrix as an Informetric Analysis System)

  • 이방래;여운동;이준영;이창환;권오진;문영호
    • 한국콘텐츠학회논문지
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    • 제8권1호
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    • pp.68-74
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    • 2008
  • 데이터베이스로부터 지식을 발견하고 이를 연구기획자, 정책의사결정자들이 활용하는 움직임이 전세계적으로 활발해지고 있다. 이러한 연구분야 중 대표적인 것이 계량정보학이고 이 분야를 지원하기 위해서 주로 선진국을 중심으로 분석시스템이 개발되고 있다. 그러나 외국의 분석시스템은 실제 수요자의 요구를 충분히 반영하지 못하고 있고, 고가이면서 한글이 지원되지 않아 국내 연구기획자가 사용하기에 어려운 점이 있다. 따라서 한국과학기술정보연구원에서는 이러한 단점을 극복하기 위해서 계량정보분석시스템 KnowledgeMatrix를 개발하였다. KnowledgeMatrix는 논문 및 특허의 서지정보를 분석하여 지식을 발견하기 위한 목적으로 설계된 독립형(stand-alone) 시스템이다 KnowledgeMatrix의 주요 구성을 살펴보면 행렬 생성, 클러스터링, 시각화, 데이터 전처리로 요약된다. 본 논문에서 소개하고 있는 KnowledgeMatrix는 외국의 대표적인 정보분석시스템과 비교했을 때 다양한 기능을 제공하고 있고 특히 영문데이터 처리 이외에 한글데이터 처리가 가능하다는 장점을 갖고 있다.

Isolation of Lactococcus lactis Strain with ${\beta}$-Galactosidase Activity from Kimchi and Cloning of lacZ Gene from the Isolated Strain

  • Park, Rae-Jun;Lee, Kwang-Hee;Kim, Su-Jung;Park, Jae-Yong;Nam, Su-Jin;Yun, Han-Dae;Lee, Hyong-Joo;Chang, Hae-Choon;Chung, Dae-Kyun;Lee, Jong-Hoon;Park, Yun-Hee;Kim, Jeong-Hwan
    • Journal of Microbiology and Biotechnology
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    • 제12권1호
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    • pp.157-161
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    • 2002
  • A lactic acid bacteria with ${\beta}$-gal activity was isolated from Kimchi, a traditional fermented vegetable food in Korea. The isolate was identified as a Lactococcus lactis strain and named L. lactis A2. The gene encoding ${\beta}$-gal of L. lactis A2 was cloned as a 5.8 kb PstI fragment. DNA sequencing identified the complete lacA (galactoside acetyltransferase)-lacZ (${\beta}$-galactosidase) genes together with the 3' part of upstream galT (galactose-1-phosphate uridyltransferase), and the 5'region of downstream galE (UDP-galactose-4-epimerase) genes. L. lactis A2 had the same gal/lac operon structure as in L. lactis subsp. lactis 7962. Other genes of the Leloir pathway are most likely to be located in the 5'upstream of the 5.8 kb fragment on the A2 chromosome. Sequences downstream of galE were different from those of L. lactis subsp. lactis 7962.

근골격계 질환 수술 후 한방치료 동향(국내 학술지를 중심으로) (Trends of Korean Medicine Treatment after Musculoskeletal Disorder Surgery: A Literatural Review)

  • 이강준;박창현;이윤재;이정한;조재흥;박태용;양나래;황의형;송윤경
    • 한방재활의학과학회지
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    • 제27권3호
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    • pp.61-70
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    • 2017
  • Objectives The purpose of this review is to analyse the trend in papers related with Korean Medicine Treatment after musculoskeletal disorder surgery. Methods We reviewed Korean Medicine papers by searching Korean web databases 'Korea Traditional Knowledge Portal', 'Scientific and Technological Information Integration Service (NDSL)', 'Academic Research Information Service (RISS)', 'Korea Medical Informati on Portal (OASIS)'. We classified the papers by the year of publishment, the title of journals, the type of study, surgery region, chief complain after surgery, main treatment, periods after surgery, assessment for outcomes. Results 1. Korean Medicine treatment after musculoskeletal disorder surgery has received more attention than in the past and there are attempts to do various studies besides the case reports. 2. 41 research papers were divided in to 3 original articles, 3 review articles, 35 case reports. But almost presented a low level of evidence. 3. Pain was the most common symptom after the musculoskeletal disorder surgery. Pain should be the primary goal of Korean rehabilitation treatment after musculoskeletal disorder surgery. 4. Assessment tools for outcome were concentrated in questionnaries, VAS and NRS. In order to evaluate better, it is necessary to evaluate the overall condition of the patient such as the quality of life evaluation and patient satisfaction. Conclusions In this study, we expect that the development and clinical application of Korean rehabilitation treatment program after musculoskeletal disorder surgery will be actively pursued.

입자크기비에 따른 강-연성 혼합재의 공학적 특성 (Characteristics of Rigid-Soft Particle Mixtures with Size Ratio)

  • 이창호;윤형구;김래현;이우진;이종섭
    • 한국지반공학회논문집
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    • 제24권8호
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    • pp.125-135
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    • 2008
  • 모래 입자와 연약한 고무 입자로 이루어진 강-연성 혼합재의 응력-변형 및 전단파 특성을 평가하기 위해 고무와 모래의 부피비(sf)와 입자 크기비(sr)를 달리하는 시료를 조성하였다. 벤더 엘리먼트가 설치된 압밀셀을 이용하여 응력-변형시험 및 $K_o$ 상태에서의 미소변형 전단파 시험을 실시하였다. 일정한 입자 크기비를 가지는 강-연성 혼합재는 강성의 입자에서 연성의 입자로 거동이 전이되는 응력-변형 및 미소변형 전단파 특성을 보였다. 또한, $G_{max}=\;{\Lambda}({\sigma}'_{o}/kPa)^{\zeta}$ 관계에서 모래의 부피비(sf)가 $0.4{\sim}0.6$인 구간에서 $\Lambda$계수가 급격히 증가하며 $\zeta$ 지수는 최대값을 보이는 것으로 관찰되었다. 전이 혼합재는 구속응력의 변화에 매우 민감한 거동을 보이며 연성인 고무입자는 재하 하중에 의해 쉽게 변형되므로 최소 간극율을 가지는 강-연성 혼합재의 부피비는 재하된 응력의 크기에 좌우된다. 실내시험을 이용한 본 연구에서는 입자 크기 비와 모래 부피비가 강성 입자와 연성 입자의 혼합재료 거동을 결정하는 것으로 요인으로 분석되었다.

Improvement of Virus Safety of a Human Intravenous Immunoglobulin by Low pH Incubation

  • Kim, In-Seop;Choi, Yong-Woon;Lee, Sung-Rae;Cho, Hang-Bok;Eo, Ho-Gueon;Han, Sang-Woo;Chang, Chong-Eun;Lee, Soung-Min
    • Journal of Microbiology and Biotechnology
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    • 제11권4호
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    • pp.619-627
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    • 2001
  • n order to increase the virus safety of a human intravenous immunoglobulin (IVIg) that was manufactured by a successive process of cold ethanol fractionation, polyethylene glycol precipitation, and pasteurization ($60^{\circ}C$ heat treatment for 10h), a low pH incubation process (pH 3.9 at $25{\circ}C$ for 14 days) was employed as the final step. The efficacy and mechanism of the fraction III cold ethanol fractionation, pasteurization, and low pH treatment steps in the removal and/or inactivation of blood-borne viruses were closely examined. A variety of experimental model viruses for human pathogenic viruses, including the Bovine herpes virus (BHV), Bovine viral diarrhoea virus (BVDV), Murine encephalomyocarditis virus (EMCV), and Porcine parvovirus (PPV), were selected for this study. The mechanism of reduction for the enveloped viruses (BHV and BVDV) during fraction III fractionation was both inactivation and partitioning, however, it was partitioning in the case of the nonenveloped viruses (EMCV and PPV). The log reduction factors achieved during fraction III fractionation were ${\geqq}$6.7 for BHV, ${\geqq}4.7$ for BVDV, 4.5 for EMCV, and 4.4 for PPV. Pasteurization was found to be a robust and effective step in inactivating all the viruses tested. The log reduction factors achieved during the pasteurization process were ${\geqq}7.5$ for BHV, ${\geqq}4.8$ for BVDV, 3.0 for EMCV, and 3.3 for PPV. A low pH incubation was very effective in inactivating the enveloped viruses as well as EMCV. The log reduction factors achieved during low pH incubation were ${\geqq}7.4$ for BHV, ${\geqq}3.9$ for BVDV, 5.2 for EMCV, and 2.0 for PPV. These results indicate that the low pH treatment successfully improved the viral safety of the final products.

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3차원 안면자동인식기의 형상복원 오차검사 (An Error Examination of 3D Face Automatic Recognition)

  • 석재화;조경래;조용범;유정희;곽창규;이수경;고병희;김종원;김규곤;이의주
    • 사상체질의학회지
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    • 제18권2호
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    • pp.41-49
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    • 2006
  • 1. Objectives The Face is an important standard for the classification of Sasang Contitutions. We are developing 3D Face Automatic Recognition Apparatus to analyse the facial characteristics. So We should examine a shape demobilization error of 3D Face Automatic Recognition Apparatus. 2. Methods We compared facial shape data be demobilized by 3D Face Automatic Recognition Apparatus with facial shape data that be demobilized by 3D laser scanner. The subject was two korean men. And We analysed the average error and the maximum error of two data. In this process, We used one datum point(the peak of nose) and two datum line(vertical section and horizontal section). 3. Results and Conclusions In each this comparison, the average error of vertical section was 1.962574mm and 2.703814mm. and the maximum error of vertical section was 16.968249mm and 18.61464mm. the average error of horizontal section was 4.173203mm and 21.487479mm. and the maximum error of horizontal section was 3.571210mm and 17.13255mm. Also We complemented this apparatus a little and We reexamined a shape demobilization error of 3D Face Automatic Recognition Apparatus again. Accuracy of a shape demobilization was improved a little. From now on We complement accuracy of a shape demobilization in 3D Face Recognition Apparatus.

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Analysis of epididymal sperm from Korean native bull (Hanwoo) aged at 8 and 15 months before freezing and after thawing

  • Kang, Sung-Sik;Cho, Sang-Rae;Kim, Ui-Hyung;Park, Chang-Seok;Kim, Hyeong-Cheol;Chung, Ki-Yong;Lee, Seok-Dong;Jang, Sun-Sik;Jeon, Gi-jun;Kim, Sidong;Lee, Myeong-Suk;Yang, Byoung-Chul
    • 한국수정란이식학회지
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    • 제31권2호
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    • pp.109-116
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    • 2016
  • The recovery of epididymal sperm in animals is considered as one of the important tools to preserve high value or endangered species. However, there are no appropriate castrating indicators such as months of age in bull, sperm morphology, and motility, particularly in young Korean native bull (Hanwoo). Therefore, this study aimed to investigate sperm number, morphology, and motility of sperm in the epididymis tail of young Hanwoo bulls at 8 and 15 months of age. After castration, epididymal tails were collected and minced with blades to recover sperm. In experiments 1 and 2, sperm number, morphology, and motility were examined. Total number of sperm and percentage of normal sperm from bulls at 8 months of age was lower than that of bulls at 15 months of age after collection (P<0.05). Percentage of abnormal head, tail, proximal cytoplasmic droplet, dead and damaged acrosome of sperm from bulls at 8 months of age were higher than those of bulls at 15 months of age (P<0.05). In experiment 3, sperm motility from bulls at 8 and 15 months of age were examined before freezing and after thawing. Frozen-thawed sperm at 8 months of age showed low total motility and motile sperm with ${\geq}25{\mu}m/sec$ compared to those at 15 months of age and commercially-used sperm (P<0.05). In conclusion, sperm derived from the epididymal tail of bulls at 8 months of age showed high abnormal morphology and poor motility, which are not adequate for AI and IVF. On the other hand, sperm derived from the epididymal tail of bulls at 15 months of age showed high normal morphology and motility.