• 한국가축번식학회지
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• 제19권2호
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• pp.81-88
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• 1995

Culture medium (ASF-301) of tHUE-2 cell, human endothelial cell line, and culture medium of these cells (conditioned medium : CM) which affect embryonic development of in vivo fertilized 1-cell embryos of mouse were examined. Two-cell stage block of mouse embryos was overicomed in ASF-301 and CM without EDTA, which usually added in basic medium (modified Whitten Medium: MWM, control) to overcome the 2-cell stage block. The developmental rates of embryos to the blastocyst stage were significantly increased in MWM containing 12.5% of growth factors added to ASF-301 (10mg/ $\ell$ transferrin, 1mg/$\ell$ insulin, 0.01mg/$\ell$ EGF) than those of 100% addition and control, 78.0% vs 20.8 and 52.3%, respectively (P<0.05), but the growth factors was not affected the hatching rate of blastocyst. Using ASF-301 or CM which was not treated, embryonic development into the blastocyst and hatched blastocyst stages were not affected. However, proportions of embryonic development into the blastocyst and hatched blastocyst stages were significantly higher in dilution (ASF-301 1:10; CM 1:3~1:6) than those in control (P,0.05). In ASF-301 dialyzed M.W.<10000 dialysis membrane, the developmental rate upto the hatched blastocyst stage was significantly increased, compared to ASF-301 which was not dialyzed (P<0.05), and hatching rate of blastocyst of these group was singnificantly increased than those in MWM (P<0.05). Compared to CM which was not dialyzed, however, in dialyzed CM was significantly decreased, compared to untreated CM (P<0.05), especially any hatched blastocyst was not appeared. As a result of these experiments indicated that a kind or porper treatment such as a dilution of complex synthetic cell culture medium and conditioned medium, and that a optimal concentration of growth factors are usuful for embryo cultrue in vitro.

• 한국항행학회논문지
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• 제11권1호
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• pp.1-8
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• 2007

본 논문에서는 해양/항공안전, 차량항법, 정밀농업, 정밀측량 등 우리사회 전반에 걸쳐 이용자가 급속히 확산되고 있는 GPS(Global Positioning System) 인프라에 대한 이용 불능상태를 대비하여 국가항법체계의 혼란을 예방하고 전파항법에 대한 BACK-UP 기능을 부여할 수 있는 지상 송신국 기반의 로란-C 항법의 활용을 제안하였다. 로란-C의 활용가치를 높이기 위한 위치오차 개선방안으로 ASF (Additional Secondary Phase Factor) 산출과 적용실험을 실시하였다. 그 결과로 로란-C 위치오차 100~400m를 10~65m로 현저히 개선할 수 있다는 결론에 도달하게 되었다. 또한 육상지역의 ASF보정테이블 이용 시 산출 범위는 복합매질과 굴곡면을 가만할 때 위도, 경도 10분 이내가 적절할 것으로 판단되며 향후 한반도 전역을 대상으로 한 ASF 보정테이블 적용시 현저한 위치오차개선과 GPS BACK-UP 기능수행이 가능할 것으로 판단되어진다.

• 융합신호처리학회논문지
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• 제12권2호
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• pp.107-112
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• 2011

GPS의 원자시계 이상 및 신호 취약 현상에 대비하기 위해 유럽의 갈릴레오, 중국의 BEIDOU, 일본의 QZSS 등 세계 선진각국은 GPS에 독립적인 위성항법시스템을 구축하고 있다. 또한, 위성항법시스템의 백업 용도로 지상항법 시스템인 Loran의 현대화 시스템인 eLoran에 대한 연구가 진행되고 있다. 국내에서도 독자항법에 대한 필요성이 거론되며 GPS에 대한 백업 용도로 Loran 시스템의 현대화를 통한 시각동기 인프라로서의 활용성에 대한 요구가 증대되고 있다. Loran 선호는 100Khz 대역으로 지형환경에 영향을 받는 지표파이다. 지표파는 지형의 전도율과 고도에 의해 전파의 전달 시 추가 지연인 ASF가 발생하고 이 추가 지연은 Loran 항법 및 시각동기에 오차를 유발하는 중요한 요소이다. 이에, ASF의 보정 방법은 Loran과 eLoran 항법에 매우 중요하다. 본 논문은 Loran 신호가 지형의 특성에 따라 지연되는 전파 지연 모델을 소개하고 효율적인 전파 지연 보정 방법을 제안하기 위해 전파모델링에 의한 예측값과 실측값을 비교 분석한 결과를 제시한다.

• Journal of Veterinary Science
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• 제22권5호
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• pp.71.1-71.12
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• 2021

Background: African swine fever (ASF) is a hemorrhagic fever occurring in wild boars (Sus scrofa) and domestic pigs. The epidemic situation of ASF in South Korean wild boars has increased the risk of ASF in domestic pig farms. Although basic reproduction number (R₀) can be applied for control policies, it is challenging to estimate the R₀ for ASF in wild boars due to surveillance bias, lack of wild boar population data, and the effect of ASF-positive wild boar carcass on disease dynamics. Objectives: This study was undertaken to estimate the R₀ of ASF in wild boars in South Korea, and subsequently analyze the spatiotemporal heterogeneity. Methods: We detected the local transmission clusters using the spatiotemporal clustering algorithm, which was modified to incorporate the effect of ASF-positive wild boar carcass. With the assumption of exponential growth, R₀ was estimated for each cluster. The temporal change of the estimates and its association with the habitat suitability of wild boar were analyzed. Results: Totally, 22 local transmission clusters were detected, showing seasonal patterns occurring in winter and spring. Mean value of R₀ of each cluster was 1.54. The estimates showed a temporal increasing trend and positive association with habitat suitability of wild boar. Conclusions: The disease dynamics among wild boars seems to have worsened over time. Thus, in areas with a high elevation and suitable for wild boars, practical methods need to be contrived to ratify the control policies for wild boars.

• Journal of Veterinary Science
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• 제21권2호
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• pp.14.1-14.10
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• 2020

African swine fever (ASF) is a highly contagious disease of domestic pigs and wild boars (WBs). Without a vaccine, early antibody and antigen detection and rapid diagnosis are crucial for the effective prevention of the disease and the employment of control measures. In Sardinia, where 3 different suid populations coexisted closely for a long time, the disease persists since 1978. The recent ASF eradication plan involves more stringent measures to combat free-ranging pigs and any kind of illegality in the pig industry. However, critical issues such as the low level of hunter cooperation with veterinary services and the time required for ASF detection in the WBs killed during the hunting season still remain. Considering the need to deliver true ASF negative carcasses as early as possible, this study focuses on the evaluation and validation of a duplex pen-side test that simultaneously detects antibodies and antigens specific to ASF virus, to improve molecular diagnosis under field conditions. The main goal was to establish the specificity of the two pen-side tests performed simultaneously and to determine their ability to detect the true ASF negative carcasses among the hunted WBs. Blood and organ samples of the WBs hunted during the 2018/2019 hunting seasons were obtained. A total of 160 animals were tested using the pen-side kit test; samples were collected for virological and serological analyses. A specificity of 98% was observed considering the official laboratory tests as gold standards. The new diagnostic techniques could facilitate faster and cost-effective control of the disease.

• Journal of Veterinary Science
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• 제21권2호
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• pp.38.1-38.24
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• 2020

African swine fever (ASF), caused by the ASF virus, a member of the Asfarviridae family, is one of the most important diseases in the swine industry due to its clinical and economic impacts. Since the first report of ASF a century ago, ample information has become available, but prevention and treatment measures are still inadequate. Two waves of epizootic outbreaks have occurred worldwide. While the first wave of the epizootic outbreak was controlled in most of the infected areas, the second wave is currently active in the European and Asian continents, causing severe economic losses to the pig industry. There are different patterns of spreading in the outbreaks between those in European and Asian countries. Prevention and control of ASF are very difficult due to the lack of available vaccines and effective therapeutic measures. However, recent outbreaks in South Korea have been successfully controlled on swine farms, although feral pigs are periodically being found to be positive for the ASF virus. Therefore, we would like to share our story regarding the preparation and application of control measures. The success in controlling ASF on farms in South Korea is largely due to the awareness and education of swine farmers and practitioners, the early detection of infected animals, the implementation of strict control policies by the government, and widespread sharing of information among stakeholders. Based on the experience gained from the outbreaks in South Korea, this review describes the current understanding of the ASF virus and its pathogenic mechanisms, epidemiology, and control.

• 한국멀티미디어학회논문지
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• 제7권3호
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• pp.368-376
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• 2004

본 논문에서는, 현재 윈도우즈 미디어 기술(Windows media technology)이 스트리밍 미디어를 작성, 배포, 재생할 수 있도록 구성 된 포괄적인 개발 도구이기는 하지만 프로그램 기능상의 고난도로 인하여 일반 사용자들이 쉽게 접근하지 못하는 점을 고려, 쉽게 스트리밍 미디어를 작성 할 수 있게 해주는 저작도구를 개발한 내용을 소개한다. 기존의 마이크로소프트사의 ASF(Advanced Systems Format) 저작도구는 사용자가 직접 삽입 시간을 입력해야 하고 ASX(ASF Stream Redirector) 파일을 저작하려면 별도의 응용프로그램을 사용해야 했다. 본 저작도구는 ASF 파일 제작시 사용자의 입력을 최소화하기 위해 마커와 스크립트 커맨드 정보입력 인터페이스를 쉽게 접근할 수 있도록 설계하였으며 마커와 스크립트 커맨드의 삽입을 간단히 마우스의 조작만으로 시간과 위치를 계산할 수 있는 기능을 구현하였다. 또한, ASX 파일 생성 마법사를 사용하여 ASX 파일을 직접 코딩하지 않고도 사용자가 원하는 기능으로 ASX 파일을 저작할 수 있으며, 최종적으로 템플릿을 이용하여 ASF, ASX파일이 삽입된 웹 페이지를 간단히 생성할 수 있고 생성과 동시에 브라우저에서 확인할 수 있는 기능을 구현하였다. 본 저작도구의 장점 은 ASF 파일의 마커와 스크립트 커맨드를 편리하게 삽입하고 편집할 수 있는 InfoSlider와 자신이 원하는 템플릿을 선택할 수 있는 ASX 파일 생성 마법사를 활용하여 윈도우즈 미디어 기술에 대한 지식이 없는 사용자들도 멀티미디어 컨텐트를 손쉽게 저작할 수 있게 해주는 점이다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권11호
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• pp.1776-1788
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• 2019

Objective: The demands for measures to improve disease resistance and productivity of livestock are increasing, as most countries prohibit the addition of antibiotics to feed. This study therefore aimed to uncover functional feed additives to help enhance livestock immunity and disease resistance, using Acanthopanax sessiliflorus fruit extract (ASF). Methods: ASF was extracted with 70% EtOH, and total polyphenolic and catechin contents were measured by the Folin-Ciocalteu and vanillin assay, respectively. The 3D4/31 porcine macrophage cells ($M{\Phi}$) were activated by phorbol 12-myristate 13-acetate (PMA), and cell survival and growth rate were measured with or without ASF treatment. Flow-cytometric analysis determined the lysosomal activity, reactive oxygen species levels (ROS), and cell cycle distribution. Nuclear factor kappa B ($NF-{\kappa}B$) and superoxide dismutase (SOD) protein expression levels were quantified by western blotting and densitometry analysis. Quantitative polymerase chain reaction was applied to measure the lipid metabolism-related genes expression level. Lastly, the antibacterial activity of 3D4/31 $M{\Phi}$ cells was evaluated by the colony forming unit assay. Results: ASF upregulated the cell viability and growth rate of 3D4/31 $M{\Phi}$, with or without PMA activation. Moreover, lysosomal activity and intracellular ROS levels were increased after ASF exposure. In addition, the antioxidant enzyme SOD2 expression levels were proportionately increased with ROS levels. Both ASF and PMA treatment resulted in upregulation of $NF-{\kappa}B$ protein, tumor necrosis factor $(TNF){\alpha}$ mRNA expression levels, lipid synthesis, and fatty acid oxidation metabolism. Interestingly, co-treatment of ASF with PMA resulted in recovery of $NF-{\kappa}B$, $TNF{\alpha}$, and lipid metabolism levels. Finally, ASF pretreatment enhanced the in vitro bactericidal activity of 3D4/31 $M{\Phi}$ against Escherichia coli. Conclusion: This study provides a novel insight into the regulation of $NF-{\kappa}B$ activity and lipid metabolism in $M{\Phi}$, and we anticipate that ASF has the potential to be effective as a feed additive to enhance livestock immunity.

• Journal of Positioning, Navigation, and Timing
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• 제2권1호
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• pp.75-80
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• 2013

This article presents the design of long range navigation (LORAN)-disciplined oscillator (LDO), employing the timing information of the LORAN system, which was developed as a backup system that corrects the vulnerability of the global positioning system (GPS)-based timing information utilization. The LDO designed on the basis of hardware generates a timing source synchronized with reference to the timing information of the LORAN-C receiver. As for the LDO-based timing information measurement, the Kalman filter was applied to estimate the measurement of which variance was minimized so that the stability performance could be improved. The oven-controlled crystal oscillator (OCXO) was employed as the local oscillator of the LDO. The controller was operated by digital proportional-integral-derivative (PID) controlling method. The LDO performance evaluation environment that takes into account the additional secondary factor (ASF) of the LORAN signals allows for the relative ASF observation and data collection using the coordinated universal time (UTC). The collected observation data are used to analyze the effect of ASF on propagation delay. The LDO stability performance was presented by the results of the LDO frequency measurements from which the ASF was excluded.

• BMB Reports
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• 제42권4호
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• pp.227-231
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• 2009

The eukaryotic genome forms a chromatin structure that contains repeating nucleosome structures. Nucleosome packaging is regulated by chromatin remodeling factors such as histone chaperones. The Saccharomyces cerevisiae H3/H4 histone chaperones, CAF-1 and Asf1, regulate DNA replication and chromatin assembly. CAF-1 function is largely restricted to non-transcriptional processes in heterochromatin, whereas Asf1 regulates transcription together with another H3/H4 chaperone, HIR. This study examined the role of the yeast H3/H4 histone chaperones, Asf1, HIR, and CAF-1 in chromatin dynamics during transcription. Unexpectedly, CAF-1 was recruited to the actively transcribed region in a similar way to HIR and Asf1. In addition, the three histone chaperones genetically interacted with Set2-dependent H3 K36 methylation. Similar to histone chaperones, Set2 was required for tolerance to excess histone H3 but not to excess H2A, suggesting that CAF-1, Asf1, HIR, and Set2 function in a related pathway and target chromatin during transcription.