• Animal Bioscience
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• 제35권9호
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• pp.1444-1453
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• 2022

Objective: Acetate plays an important role in host lipid metabolism. However, the network of acetate-regulated lipid metabolism remains unclear. Previous studies show that mitogen-activated protein kinases (MAPKs) and mechanistic target of rapamycin (mTOR) play a crucial role in lipid metabolism. We hypothesize that acetate could affect MAPKs and/or mTOR signaling and then regulate lipid metabolism. The present study investigated whether any cross talk occurs among MAPKs, mTOR and acetate in regulating lipid metabolism. Methods: The ceramide C6 (an extracellular signaling-regulated kinases 1 and 2 [ERK1/2] activator) and MHY1485 (a mTOR activator) were used to treat rabbit adipose-derived stem cells (ADSCs) with or without acetate, respectively. Results: It indicated that acetate (9 mM) treatment for 48 h decreased the lipid deposition in rabbit ADSCs. Acetate treatment decreased significantly phosphorylated protein levels of ERK1/2 and mTOR but significantly increased mRNA level of hormone-sensitive lipase (HSL). Acetate treatment did not significantly alter the phosphorylated protein level of p38 MAPK and c-Jun aminoterminal kinase (JNK). Activation of ERK1/2 and mTOR by respective addition in media with ceramide C6 and MHY1485 significantly attenuated decreased lipid deposition and increased HSL expression caused by acetate. Conclusion: Our results suggest that ERK1/2 and mTOR signaling pathways are associated with acetate regulated HSL gene expression and lipid deposition.

• Geomechanics and Engineering
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• 제34권1호
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• pp.103-113
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• 2023

This study focused on understanding the relationship between the design of a tunnel boring machine disc cutter ring and its rock-breaking efficiency, as well as the applicable conditions of different cutter ring types. The discrete element method was used to establish a numerical model of the rock-breaking process using disc cutters with different ring types to reveal the development of rock damage cracks and variation in cutter penetration load. The calculation results indicate that a sharp-edged (V-shaped) disc cutter penetrates a rock mass to a given depth with the lowest load, resulting in more intermediate cracks and few lateral cracks, which leads to difficulty in crack combination. Furthermore, the poor wear resistance of a conventional V-shaped cutter can lead to an exponential increase in the penetration load after cutter ring wear. In contrast, constant-cross-section (CCS) disc cutters have the highest quantity of crack extensions after penetrating rock, but also require the highest penetration loads. An arch-edged (U-shaped) disc cutter is more moderate than the aforementioned types with sufficient intermediate and lateral crack propagation after cutting into rock under a suitable penetration load. Additionally, we found that the cutter ring wedge angle and edge width heavily influence cutter rock-breaking efficiency and that a disc cutter with a 16 to 22 mm edge width and 20° to 30° wedge angle exhibits high performance. Compared to V-shaped and U-shaped cutters, the CCS cutter is more suitable for soft or medium-strength rocks, where the penetration load is relatively small. Additionally, two typical case studies were selected to verify that replacing a CCS cutter with a U-shaped or optimized V-shaped disc cutter can increase cutting efficiency when encountering hard rocks.

• 한국식생활문화학회지
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• 제23권6호
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• pp.693-704
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• 2008

In this study, the preference for Korean Kimchi by Chinese people in Shandong Province was evaluated. Specifically, this study was conducted to aid in the introduction of Kimchi to China by providing information and developing local types designed to meet regional taste preferences. The subjects were comprised of 298 Chinese (male 108, female 190) residents of Weihai, Yantai and Qingdao, in Shandong province, China. The subjects were provided with a self administered questionnaire form designed to evaluate their views on Korean Kimchi. The collected data were then analyzed using the SAS software package. The results revealed that 95.3% of the respondents were aware of Korean Kimchi. In addition, 100% of the respondents who had visited Korea and 98.1% of the respondents who had an interest in Korea were aware of Kimchi. With regard to the origins of their interest in Kimchi, 26.8% of the subjects answered 'through mass media', while 23.9% reported that they learned about Kimchi 'through friends'. Most subjects recognized Kimchi as a 'Korean traditional food' (92.6%), a 'delicious food' (53.2%), and a 'fermented food' (38.0%). Baechu Kimchi was found to be the most well-known Kimchi, followed by Kkakdugi, Oi Kimchi, Yoelmu Kimchi and Nabak Kimchi. Additionally, 69.1% of the subjects knew how it was prepared, most of whom reported that they learned how Kimchi was prepared through 'Korean movie and/or drama'. Moreover, 88.9% of the subjects had eaten Kimchi. Overall, 43.8% of the subjects reported that they ate Kimchi $1{\sim}2$ times per month, while 32.1% reported that they ate Kimchi $1{\sim}2$ time per year. The most common places that Kimchi was eaten were a 'Korean restaurant' (67.6%) or with a 'colleague' (32.8%). The primary reasons for not having eaten Kimchi were 'no knowledge or dislike of Kimchi by family' (30.3%), 'difficulty purchasing Kimchi' (21.2%), 'high priced Kimchi' (21.2%), and 'dislike the smell and shape of Kimchi' (12.1%).

• Earthquakes and Structures
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• 제26권3호
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• pp.175-189
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• 2024

Aiming at studying the plastic hinge (PH) evolution regularities and failure mode of rocking wall moment frame (RWMF) structure in earthquakes, the whole-working history analysis of seismic performance state of RWMF structure based on co-operation performance and PH evolution was carried out. Building upon the theoretical analysis of the elastic internal forces and deformations of RWMF structures, nonlinear finite element analysis (FEA) methods were employed to perform both Pushover analysis and seismic response time history analysis under different seismic coefficients (δ). The relationships among PH occurrence ratios (R_ph), inter-story drifts and δ were established. Based on the plotted curve of the seismic performance states, evaluation limits for the R_ph and inter-story drifts were provided for different performance states of RWMF structures. The results indicate that the R_ph of RWMF structures exhibits a nonlinear evolution trend of "fast at first, then slow" with the increasing of δ. The general pattern is characterized by the initial development of beam hinges in the middle stories, followed by the development towards the top and bottom stories until the beam hinges are fully formed. Subsequently, the development of column hinges shifts from the bottom and top stories towards the middle stories of the structure, ultimately leading to the loss of seismic lateral capacity with a failure mode of partial beam yield, demonstrating a global yielding pattern. Moreover, the limits for the R_ph and inter-story drifts effectively evaluate the five different performance states of RWMF structures.

• 한국항만경제학회지
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• 제33권2호
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• pp.53-82
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• 2017

본 논문에서는 메타프론티어 DEA모형과 정수계획모형으로, 아시아 38개 컨테이너항만들의 10년간(2005-2014) 자료를 4개의 투입요소(선석길이, 수심, 총면적, 크레인 수), 1개의 산출요소(컨테이너화물처리량)를 이용하여 국내항만(부산, 인천, 광양항)들이 어떤 항만들과 클러스터링 해야만 하는지에 대한 측정방법을 실증적으로 보여 주고 비교, 분석, 검증하였다. 실증분석의 주요한 결과는 다음과 같다. 첫째, 2005년부터 2014년까지 전체자료를 이용한 메타프론티어 DEA효율성 측정의 주요한 결과를 살펴보면, 중국항만들의 메타효율성과 그룹효율성이 높게 나타났으며, 순위는 상해, 홍콩, 닝보, 칭타오, 광저우 순서였으며, 국내항만은 부산, 인천, 광양항의 순서였다. 둘째, 정수계획모형에 의한 국내항만들의 클러스터링을 살펴보면 (1)부산항은 두바이, 홍콩, 상해, 광저우, 닝보, 칭타오, 싱가포르, 카오슝 항과 클러스터링하고, (2)인천항과 광양항은 사히드 라자이, 하이파, 크호르 파칸, 탄중 퍼락, 오오사카, 키룽, 방콕 항과 클러스터링 하는 것이 좋은 것으로 나타났다. 셋째, 정수계획모형을 통한 클러스터링이 메타프론티어 DEA모형의 그룹효율성을 부산항을 제외하고 인천항은 401.84%, 광양항은 354.25%만큼 대폭적으로 상승시켰다. 넷째, 효율성 순위를 검정한 윌콕슨부호순위검정에서는 두 가지 모형[메타프론티어 DEA모형과 정수계획모형에 의한 클러스터링 전과 후의 그룹효율성(57.88%), 기술 갭 효율성(80.93%)]사이에 순위에 차이가 없는 것으로 나타났다. 본 논문이 갖는 정책적인 함의는 첫째, 항만정책입안자들이 본 연구에서 사용한 두 가지 모형을 항만의 클러스터링 정책에 도입하여 해당항만이 발전할 수 있는 전략을 수립하고 이행해 나가야만 한다는 점이다. 둘째, 본 논문의 실증분석결과 국내항만들의 참조항만, 클러스터링항만들로서 나타난 아시아항만들에 대하여, 그들 항만들의 항만개발, 운영에 대한 내용을 정밀하게 분석하고 도입하여 실시하는 것이 필요하다.

• 한국항만경제학회지
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• 제34권3호
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• pp.17-52
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• 2018

본 논문에서는 K-Means 군집모형과 계층적 군집모형, 혼합모형으로, 아시아 38개 컨테이너항만 들의 2006년부터 2015년까지의 자료와 선석길이, 수심, 총면적, 크레인 수를 투입물, 컨테이너화물처리량을 산출물로 하여 국내대표 컨테이너항만 들(부산, 인천, 광양항)이 클러스터링 해야만 하는 항만들을 적출해 내는 측정방법을 보여 주고 비교, 분석, 검증하였다. 실증분석의 주요한 결과는 다음과 같다. 첫째, 10년간의 자료를 이용한 분석에서 클러스터링 후의 효율성 증가폭이 큰 순서대로 살펴보면 평균연결법[average linkage(AL)]은 42.04% 상승, Mixed Ward는 35.01% 상승, 경험법칙[rule of thumb(RT)]&Elbow는 30.47% 상승, Ward는23.65% 상승, Mixed AL는 23.25% 상승의 순서였다. 둘째, RT와 Elbow모형에 의한 국내항만들의 클러스터링을 살펴보면 (1)부산항은 두바이, 홍콩, 광저우, 칭타오, 포트 클랑, 싱가포르, 림찬방 (2)인천항은 하이파, 포트슐탄 카부스, 담만, 크호르 파칸, 탄중프리옥, 탄중퍼락, 동경, 나고야, 오사카, 카라치, 오아심, 마닐라, 다바오, 콜롬보, 킬롱, 방콕, (3)광양항은 아카바, 크호르 파칸, 광정우, 닝보, 칭타오, 포트 클랑, 카오슝, 림찬방 항과 클러스터링 해야만 하는 것으로 나타났다. 셋째, 최적 군집 수를 살펴보면 AL(6개), Mixed Ward(5개), RT&ELBOW (4개), Ward(5개), Mixed AL(6개)가 최적 군집 수인 것으로 나타났다. 넷째, 전문가 그룹에 의해서 선호되는 항만들과 본 실증분석결과에 의해서 도출된 국내항만들의 클러스터링 되는 항만들과의 일치성 여부는 부산항은 80%, 인천항은 17%, 광양항은 50%수준에서 일치하는 것으로 검증되었다. 본 논문이 제안하고 있는 정책적인 측면의 의미는 첫째, 항만정책입안자, 항만운영관리자들이 본 연구에서 사용한 모형들을 항만의 클러스터링에 도입하여 벤치마킹항만들을 선정해야만 한다. 둘째, 실증분석의 결과로서 도출된, 국내항만들의 참조항만, 클러스터링항만들에 대하여, 그들 항만들의 항만개발, 운영방안 등에 대한 내용을 비교 분석하고 벤치마킹이 필요한 부분은 신속하게 도입하여 실시하는 것이 필요하다는 점이다.

• 한국항해항만학회지
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• 제31권3호
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• pp.197-204
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• 2007

1999년부터 2002년까지 4년간 부산항 환적 컨테이너의 연평균 증가율은 34%를 상회하는 고속 성장을 하였다. 하지만 2003년부터 2006년까지의 4년간 연평균 증가율은 7.7%로 급격히 감소하였으며, 더구나 2006년에는 0.6% 성장에 그쳐 그 동안 부산항 물동량 증가에 견인차 역할을 해오던 환적 컨테이너의 지속적인 성장이 관심사항으로 대두되었다. 이러한 현상은 부산항 환적 컨테이너의 45% 이상을 차지하고 있는 중국과 일본 항만의 환경 변화와 밀접한 관련이 있다. 즉, 북중국 주요 3개 항만에 대한 대형 선사들의 직 기항 증가와 상해의 심수항 개장은 부산항의 환적 컨테이너 유치에 심각한 타격을 가하고 있다. 일본 역시 항만 경쟁력을 높여 자국화물을 지키기 위해서 슈퍼 중추 항만 구상을 실현해 가고 있다. 본 연구는 부산항의 항로 교차형 및 중심 분산형의 환적 유형 및 처리 실태를 분석하고, 이를 토대로 환적 컨테이너를 지속적으로 유치할 수 있는 정책적 방향을 모색해보고자 한다. 즉, 대형 선사들이 부산항을 환적 거점항으로 이용할 수 있도록 전용 터미널을 제공하는 것 등이 바로 그것이다.

• Asian-Australasian Journal of Animal Sciences
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• 제27권4호
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• pp.471-478
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• 2014

Investigating gene expression of immune cells of whole blood or peripheral blood mononuclear cells (PBMC) under polyinosinic:polycytidylic acid (poly I:C) stimulation is valuable for understanding the immune response of organism to RNA viruses. Quantitative real-time PCR (qRT-PCR) is a standard method for quantification of gene expression studies. However, the reliability of qRT-PCR data critically depends on proper selection of reference genes. In the study, using two different analysis programs, geNorm and NormFinder, we systematically evaluated the gene expression stability of six candidate reference genes (GAPDH, ACTB, B2M, RPL4, TBP, and PPIA) in samples of whole blood and PBMC with or without poly I:C stimulation. Generally, the six candidate genes performed a similar trend of expression stability in the samples of whole blood and PBMC, but more stably expressed in whole blood than in PBMC. geNorm ranked B2M and PPIA as the best combination for gene expression normalization, while according to NormFinder, TBP was ranked as the most stable reference gene, followed by B2M and PPIA. Comprehensively considering the results from the two programs, we recommended using the geometric mean of the three genes, TBP, PPIA and B2M, to normalize the gene expression of whole blood and PBMC with poly I:C stimulation. Our study is the first detailed survey of the gene expression stability in whole blood and PBMC with or without poly I:C stimulation and should be helpful for investigating the molecular mechanism involved in porcine whole blood and PBMC in response to poly I:C stimulation.

• 한국수정란이식학회지
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• 제33권3호
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• pp.139-147
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• 2018

Somatic cell nuclear transfer (SCNT) is a useful biotechnological tool for animal cloning. Until now, SCNT has been inefficient, especially in dog. It is believed that an embryo developmental block in SCNT embryos is cause of low production efficiency. However, no studies have been performed on canines for embryo developmental block. In this study, we attempted to evaluate the beneficial role of EDTA in canine parthenogenic (PA) embryos development to overcome embryo developmental block. The PA embryos were divided into 0.01 mM EDTA treated and non-treated groups. Embryo developmental efficiency was measured by activating chemically parthenote. After EDTA induction, PA embryos were evaluated for embryonic development, Reactive Oxygen Species (ROS) activity, mitochondrial integrity, ATP production and genomic activation. The EDTA treated PA embryos showed significantly higher survival rate and improved cavity formation compared to non-treated. Furthermore, cytoplasmic ROS level was mitigated and mitochondrial membrane potential was found significantly higher in EDTA treated group followed by higher ATP production. Moreover, major embryonic genomic activation specific markers/factors were also elevated in EDTA treated group. Conclusively, we elucidated that EDTA showed substantially positive effect to overcome embryo developmental block in canine.

• 농약과학회지
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• 제13권4호
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• pp.241-248
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• 2009

본 연구는 포도 재배 중 살충제 bifenthrin을 살포하고, 살포 후 0, 1, 2, 3, 5, 7, 10, 15일에 포도 시료를 채취하여 bifenthrin을 분석하고 bifenthrin의 생물학적 반감기를 산출한 다음 생산단계 농약 잔류허용기준(PHRL; Pre-Harvest Residue Limit)을 설정하였다. 포도 중 bifenthrin은 acetonitrile과 dichloromethane 으로 추출 및 분배 하여 GC/ECD로 분석 하였다. Bifenthrin의 정량한계는 0.01 ng이었고, 평균 회수율은 0.1 및 $0.5\;mg\;kg^{-1}$ 두 수준에서 각각 $104.08{\pm}1.24%$와 $92.25{\pm}3.13%$이었다. 포도 중 bifenthrin의 기준량 및 배량 살포시 생물학적 반감기는 각각 21일과 23일로 계산되었다. 또한 증체량에 따른 희석효과가 bifenthrin의 잔류량 감소에 있어 주요인자로 작용하지는 않았다. 잔류감소 회귀식을 이용한 생산단계 농약 잔류허용기준은 수확 10일전 $0.60\;mg\;kg^{-1}$, 또는 5일전 $0.55\;mg\;kg^{-1}$으로 제안하였다.