• Journal of Animal Science and Technology
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• 제54권3호
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• pp.219-226
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• 2012

Gender specificity in muscle growth and development is well known. Genesis of muscle is dependent on proliferation and differentiation potential of resident myogenic satellite cells (MSCs) present in muscle fibers. Multipotential capacity of forming myocyte, osteocyte, and adipocyte like cell makes MSCs a unique stem cell. To understand the molecular mechanism involved in determination of muscle quality due to difference in hormone concentration of different gender of animals, MSCs were isolated from bovine skeletal muscle and cultured in male, female, and castrated serum supplemented media. DNA microarray used consisted of 24,000 spots with 70 mer oligo in each spot. A total of 88 genes were up-regulated and 551 genes were down-regulated by more than two fold. Among up-regulated gene, 33, 34, and 21 genes were found up-regulated in cells grown in male, female, and castrated serum, respectively. Interestingly, male serum showed 4, female 11 and castrated male showed 4 genes expressed highly in each gender. Further study on the highly up-regulated gene may unfold the mystery of gender specificity found in muscle development. Also, the identification of differentially expressed genes in gender-specific serum will add information on infrastructure of bovine genome research.

• Educational Technology International
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• 제24권2호
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• pp.203-236
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• 2023

The purpose of this study is to explore the structural relationship between COVID-19-induced sub-dimensions of Online Self-Regulated Learning (OSRL) and satisfaction in online courses conducted in the 'post-COVID-19 era,' as well as to investigate the moderating effects of situational variables such as 'course planning,' 'device type,' and 'course repetition.' To achieve this, the study constructs a measurement model with sub-dimensions of Environment Structuring, Learning Strategy, Help Seeking, and Self-Evaluation as components of OSRL. Participants in this study were selected from university students who enrolled in online courses offered by the Department of Education at University A in the metropolitan area. The research findings reveal several key insights. First, among the sub-dimensions of Online Self-Regulated Learning, Environment Structuring, Learning Strategy, and Self-Evaluation significantly influence satisfaction with online courses. Second, students' satisfaction with online courses significantly influences their intention to continue participating in such courses. Third, 'course planning' during online course hours and 'course repetition' play a moderating role in the relationship between sub-dimensions of Online Self-Regulated Learning and satisfaction. Based on the discussion of these research results, this study concludes by suggesting some future implications and challenges of online courses.

• 디지털융복합연구
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• 제11권12호
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• pp.829-834
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• 2013

본 연구에서는 수업에서 갖는 성취목표지향성과 자기조절학습전략이 학업성취에 미치는 영향에 대해 살펴봄으로써 효율적인 교수-학습방안을 모색하고자 하였다. 치위생과에 재학 중인 133명의 학생을 대상으로 설문조사를 실시하여 성취목표지향성과 자기조절학습전략의 평균과 표준편차, 성취목표지향성과 자기조절학습전략의 학업성취와의 관계를 분석하고, 성취목표지향성과 자기조절학습전략이 학업성취에 미치는 영향을 분석하였다. 연구결과로 학업성취도를 높이기 위해서는 성취목표지향성의 경향과 자기조절학습능력이 높을수록 학업성적이 높은 것으로 나타나 학생들의 학업성취도에 대한 동기조절훈련과 멘토링 학습을 통한 불안을 해소하고 적극적인 수업 참여 유도가 필요하다고 판단된다.

• 한국초등수학교육학회지
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• 제13권1호
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• pp.51-74
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• 2009

본 연구의 목적은 사이버 가정학습 체제 내에서 자기조절학습이 효과적으로 이루어 질 수 있는 다양한 전략들을 탐색하고 그러한 전략들을 바탕으로 사이버가정학습을 운영하여 학생들의 학습을 관리 지원함으로써 자기조절 학습능력 및 태도에 어떠한 영향을 미치는지 알아보는데 있다. 우선 선행 연구를 바탕으로 자기조절학습의 구성 요소를 인지 전략, 초인지 전략, 동기전략의 3가지 요소로 나누고 그에 따라서 사이버가정학습 운영 전략을 마련하였다. 다음으로 사이버가정학습 진행을 위한 학습 콘텐츠를 개발하고, 운영 전략에 따라 사이버가정학습을 운영하였다. 그 결과 많은 학생이 자기 조절 학습 능력이 향상됨을 보였고 수학에 흥미와 자신감을 가지게 되었다.

• BMB Reports
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• 제36권1호
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• pp.120-127
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• 2003

The formation of new blood vessels, angiogenesis, is an essential process during development and disease. Angiogenesis is well known as a crucial step in tumor growth and progression. Angiogenesis is induced by hypoxic conditions and regulated by the hypoxia-inducible factor 1 (HIF-1). The expression of HIF-1 correlates with hypoxia-induced angiogenesis as a result of the induction of the major HIF-1 target gene, vascular endothelial cell growth factor (VEGF). In this review, a brief overview of the mechanism of angiogenesis is discussed, focusing on the regulatory processes of the HIF-1 transcription factor. HIF-1 consists of a constitutively expressed HIF-1 beta(HIF-1β) subunit and an oxygen-regulated HIF-1 alpha(HIF-1α) subunit. The stability and activity of HIF-1α are regulated by the interaction with various proteins, such as pVHL, p53, and p300/CBP as well as by post-translational modifications, hydroxylation, acetylation, and phosphorylation. It was recently reported that HIF-1α binds a co-activator of the AP-1 transciption factor, Jab-1, which inhibits the p53-dependent degradation of HIF-1 and enhances the transcriptional activity of HIF-1 and the subsequent VEGF expression under hypoxic conditions. ARD1 acetylates HIF-1α and stimulates pVHL-mediated ubiquitination of HIF-1α. With a growing knowledge of the molecular mechanisms in this field, novel strategies to prevent tumor angiogenesis can be developed, and form these, new anticancer therapies may arise.

• 한국통신학회논문지
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• 제29권9A호
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• pp.973-982
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• 2004

고속 스케듈링 기법은 입력 큐 스위치의 성능을 극대화하기 위해 필요하다 가상 출력큐 스위치 구조에 관하여 지금까지 iSLIP, DRRM 과 같은 라운드로빈 스케듈링 기법이 제안되어 왔다 iSLIP 방식은 높은 성능을 보여주고 있고 이미 하드웨어 구현이 되어 있고 DRRM 또한 iSLIP 보다 간단하고 성능에 더 좋음을 나타내고 있지만 , 울다 라운드로벤의 포인터통기 문제를 효과적으로 풀지 못하고 있다 본 논문에서 제안된 딸고리즘은 DRRM 알고리즘 에 기초로써 새롭게 제안되었고 포인터를 항상 비동기되도록 유지하는 특정이 있다. 또한 라운드로빈 방식을 그대로 견지하므로써 구현이 간편한 특성을 가지고 있다 시뮬레이션 결과에 의하면 제안된 알고리즘은 다양한 트래픽 모델에서 iSLIP 이나 DRRM 보다 더 좋은 성능을 보여주고 있다.

• 생명과학회지
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• 제14권5호
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• pp.874-881
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• 2004

혈관 신생은 암의 성장 및 전이뿐만 아니라 염증, 관절염, 건성, 동맥경화 등의 병적인 진행에 주요한 역할을 하며, 혈관신생 억제를 통한 암의 치료를 시도하는 연구들이 활발하게 진행되고 있다. 혈관 신생 시 내피세포의 증식, 이동을 유도하는 활성화 과정이 필수적으로 일어나는 것으로 알려져 있다 본 연구에서는 in vitro에서 내피세포를 배양하여, 각종 growth factor가 풍부한 배지에서 활성화 시켰을 때, 그렇지 않는 세포들과의 유전자 발현 형태를 비교 조사하였다. HUVEC을 70∼80% cofluency로 배양시킨 후에 endothelial cell growth supplement (ECCS), 20% fetal bovine serum, heparin이 첨가된 Ml99 배지에서 13 시간 활성화시킨 세포(AHUVEC)와 대조군 세포(RHUVEC)로부터 분리한 total RNA로부터 CDNA를 제작하였고, 이것을 18,864 개의 유전자가 올려져있는 인간 올리고 칩과 hybridization 반응을 시켰다. 반응된 유전자를 이용하여 random clustering분석을 실시한 결과, 활성화 시켰던 HUVEC과 그렇지 않은 HUVEC으로 dendrogram 상에서 두개의 subgroup으로 나뉘어 지는 것을 확인할 수 있었다. 최소 2배 이상 발현 변화가 있는 유전자 122종이 활성화 시켰던 HUVEC으로부터 추출되었다. 이중에서 기능이 알려진 32 개의 유전자는 활성화시킨 HUVEC에서 발현이 증가하였고, 38 개의 유전자 발현은 감소하였다. 흥미롭게도 세포 증식과 이동, 염증, 면역반응에 관련한 유전자의 발현이 증가된 반면에 세포 흡착과 혈관 조직과 기능에 관련한 유전자의 발현이 감소된 것이 관찰되었다. 예상외로 규명이 잘된 혈관신생 인자와 관련한 유전자들의 발현에는 크기 차이를 보이지 않았으나, Eph-B4의 발현은 약 4 배 감소된 것으로 관찰되었다 또한, 2배 이상 발현에 차이를 보이고 기능이 알려져 있지 않은 유전자 52종이 발견되었다. 따라서, 이러한 연구 결과로부터 새로운 혈관 표적 물질 개발에 대한 기회가 제공될 수 있을 것이라 사료된다.

• 한국산업정보학회:학술대회논문집
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• 한국산업정보학회 2006년도 춘계 국제학술대회 논문집
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• pp.221-228
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• 2006

With the increasing use of the Internet improved Internet technologies as well as web-based applications, the effectiveness assessment of e-Learning has become one of the most practically and theoretically important issues in both Educational Engineering and Information Systems. This study suggests a research model, based on an e-Learning success model, the relationship of the e-learner's self-regulated learning strategy and the quality perception of the e-Learning environment. This research model focuses on the learning environment and on e-learning strategy. The former consists of learning management system, learning content quality and service quality that are provided by e-Loaming. The latter refers to the learners' self-regulated learning strategy. We will show the validity of the model empirically.

• BMB Reports
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• 제33권5호
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• pp.396-401
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• 2000

A differential display method is used to identify novel genes whose expression is affected by treatment with ferric ammonium citrate (FAC) or desferrioxamine (DFO), an iron chelating agent in the human hepatoblastoma cell line (HepG2). These chemicals are known to deplete or increase the intracellular concentration of iron, respectively. Initially, we isolated seventeen genes whose expressions are down- or up regulated by the treatment of the chemicals, as well as their four differentially expressed genes that are designated as clone-1, -2, -3, and -4. These are further characterized by cDNA sequencing and Northern blot analysis. Through the cDNA sequencing, as well as comparing them to genes published using the NCBI BLAST program, we identified the sequence of the clone-1 that is up-regulated by the treatment of DFO. It is identical to the human insulin-like growth factor binding protein-1 (IGFBP-1). This suggests that the IGFBP-1 gene in the HepG2 cell is up-regulated by an iron depletion condition. Also, the expression of the clone-3 and -4 is up-regulated by FAC treatment and their eDNA sequences are identical to the human ferritin-fight chain and human NADH-dehydrogenase, respectively. However, the sequence of the clone-2 has no significant homology to any other known gene. Therefore, we suggest that changes of the cellular iron level in the HepG2 cell affects the transcription of cellular genes. This includes human IGFBP-1, ferritin-fight chain, and NADH-dehydrogenase. Regulation of these gene expressions may have an important role in cellular functions that are related to cellular iron metabolism.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.102-102
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• 2000

In this paper, attitude control laws are proposed for an underactuated spacecraft. The stabilization problem of the complete system including the kinematics as well as the dynamics of the spacecraft is addressed. The quaternion parameterization is used. The key idea is that the angular velocity of a uncontrolled axis is first regulated and then, the other states are regulated. Based on numerical simulations, it is conjectured that the closed-loop nonlinear system of a spacecraft with the proposed control laws is globally asymptotically stable. The control law for the stabilization problem around the origin as well as the command following problem are proposed. The numerical examples indicate that the stabilization of an underactuated asymmetric spacecraft can be achieved successfully.