• Restorative Dentistry and Endodontics
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• 제23권1호
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• pp.328-338
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• 1998

Porphyromonas endodontalis, an anaerobic Gram negative cocobacillus which was known to be associated with the infected root canals and periapical lesions, is very difficult to culture and to detect by the traditional method in that it requires much time to induce the specific black pigmentation, and it is very sensitive to oxygen and the antibiotics added in the culture medium. In this study, the nucleotide sequences of the 'probe h' (0.73kb), one of the specific DNA probes top. endodontalis (ATCC 35406) which had been developed by our department, was determined and then a pair of primers for PCR amplification was fabricated to identify P. endodontalis. The plasmids containing 'probe h' were purified by $Wizard^{TM}$ Midipreps DNA Purification System (Promega Corp.), and the nucleotide sequences of the 'probe h' were determined by the dideoxy chain termination method using TaqTrack Sequencing System (Promega Corp.) and detected by fluorescent labelling method. The sense/antisense PCR primers were designed with computer software (Lasergene, DNASTAR Ind. PCR was done with a programmable GeneAmp PCR System 2400 (Perkin Elmer-Cetus Co.). Each sample containing the whole genomic DNA of P. endodontalis and other black-pigmented Bacteroides was itailly denatured at $94^{\circ}C$ for 5 min and then subjected to 30 cycles, each of them consisting of 60s at $94^{\circ}C$, 60s at $60^{\circ}C$, and 90s. at $72^{\circ}C$. The amplified DNA was resolved electrophoretically in a 1.0 % agarose gel in 1X TAE buffer, stained with EtBr, and photographed on a UV transilluminator. The results were as follows : 1. The nucleotide sequences of 'probe h' (743 base pairs) were obtained by dideoxy chain termination method, and from that results the specific primers to P. endodontalis (ATCC 35406), 'Primer H1/ Primer H2', were designed. 2. It has been found that 'Primer H1/H2' could detect P. endodontalis (ATCC 35406) using PCR. 3. The PCR system with this primers may be a powerful technique to amplify the specific sequences of 'probe h' of P. endodontalis (ATCC 35406) that produce distinct identification of it from other black-pigmented Bacteroides, and this could help us to determine the nature of periapical disease.

• Elastomers and Composites
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• 제32권1호
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• pp.29-36
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• 1997

The change of elastic modulus(E'), loss modulus(E"), and loss $tangent(tan{\delta})$ were investigated on condition of double strain amplitude (DSA) at temperature of $-40{\sim}80^{\circ}C$ for carbon black filled natural rubber. E', E", and $tan{\delta}$ were increased as it closed to the glass transition temperature due to decrease of rubber network flexibility and carbon black agglomerate interaction. In the micro strain range, energy loss showed maximum value because of the chain slippage in rubber matrix, but the regeneration of carbon black agglomerate and rubber matrix affected decrease of energy loss over the mid-range strain. As a results of regression analysis, $E'\;_{max}$ correlation with ${\Delta}E'$ $(E'\;_{0.4%DSA}-E'\;_{2.0%DSA})$ showed linear relationship.

• Macromolecular Research
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• 제8권2호
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• pp.73-79
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• 2000

The influence of mastication of natural rubber (NR) on properties of carbon black-filled NR compounds was studied. Variations of viscosities of the masticated NR and the carbon black-filled NR compound by heating were also investigated. The viscosities of the compounds decreased by increasing the mastication time of the raw rubber. The viscosities of the masticated NR and the compounds increased by increasing the heating time. This was explained by the combination reaction between functional groups in the rubber. The viscosity increment of the masticated rubber and the compounds by heating became larger with increased mastication time. Cure rate of the compound became faster by increasing the mastication time. Modulus of the vulcanizate made of the rubber masticated for a long time was higher than that of the vulcanizate made of the rubber masticated for a short time while elongation at break of the former was shorter than that of the latter. This was explained by the content of bound rubber and chain length of the rubber molecules.

• 한국응용과학기술학회지
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• 제29권1호
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• pp.13-18
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• 2012

금속 주조시 사용되는 탄소이형제를 카본블랙과 점증제 겸 알데하이드 화합물의 경화제로 사용될 수 있는 수용성 고분자인 잔탄검(X-gum), 카르복시메틸셀룰로오스(CMC)을 혼합하여 제조하였다. 이 때 카본블랙의 안정한 분산을 위하여 0.25 wt%의 X-gum 또는 1.0 wt%의 CMC가 적당하였다. 1.0 wt% 보다 낮은 농도의 CMC를 사용했을 경우 카본블랙이 매우 쉽게 층분리되었다. 유리판에 대한 부착력은 경화제와, 구르탈알데하이드 및 사슬연장제인 올리고당의 양에 비례하였으며. X-gum으로 제조된 탄소 이형제는 CMC를 이용해 제조된 것보다 유리에 대한 부착력이 우수하였다. 결과적으로 본 실험의 최적 조건에서 제조된 탄소이형제는 친환경적으로 주조시에 적용할 수 있을 것으로 판단된다.

• Animal Bioscience
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• 제36권9호
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• pp.1367-1375
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• 2023

Objective: Pigment production and distribution are controlled through multiple proteins, resulting in different coat color phenotypes of sheep. Methods: The expression distribution of vimentin (VIM) and transthyretin (TTR) in white and black sheep skins was detected by liquid chromatography-electrospray ionization tandem MS (LC-ESI-MS/MS), gene ontology (GO) statistics, immunohistochemistry, Western blot, and quantitative real time polymerase chain reaction (qRT-PCR) to evaluate their role in the coat color formation of sheep. Results: LC-ESI-MS/MS results showed VIM and TTR proteins in white and black skin tissues of sheep. Meanwhile, GO functional annotation analysis suggested that VIM and TTR proteins were mainly concentrated in cellular components and biological process, respectively. Further research confirmed that VIM and TTR proteins were expressed at significantly higher levels in black sheep skins than in white sheep skins by Western blot, respectively. Immunohistochemistry notably detected VIM and TTR in hair follicle, dermal papilla, and outer root sheath of white and black sheep skins. qRT-PCR results also revealed that the expression of VIM and TTR mRNAs was higher in black sheep skins than in white sheep skins. Conclusion: The expression of VIM and TTR were higher in black sheep skins than in white sheep skins and the transcription and translation were unanimous in this study. VIM and TTR proteins were expressed in hair follicles of white and black sheep skins. These results suggested that VIM and TTR were involved in the coat color formation of sheep.

• 한국동물위생학회지
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• 제35권2호
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• pp.129-131
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• 2012

Blood samples were collected from 672 goats in 60 farms from five provinces of Korea between November 2009 and August 2011. The prevalence of antibodies to pestiviruses was investigated. The examination for antibodies was performed using an enzyme-linked immunosorbent assay (ELISA) detecting antibodies to the bovine viral diarrhea virus (BVDV) and border disease virus (BDV). All blood samples were screened using reverse transcription-polymerase chain reaction (RT-PCR) with primer pairs specific to common pestivirus genome regions. The observed individual seroprevalence was 1.49% and herd seroprevalence was 11.67%. Also, the specific genomes to pestiviruses were detected in 3 out of the 915 clinical samples (0.45%). Based on the nucleotide sequence data, detected pestiviruses were belonged to two BVDV type-1 and one BVDV type-2. The pestivirus infection has been occurred among Korean black goats. However, our results indicate that the prevalence of pestiviruses in black goats was not significantly higher on farms with cattle.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제4권4호
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• pp.154-158
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• 2023

The Asiatic black bear, Ursus thibetanus, is among the most threatened or endangered species in Asia. For its conservation and management, sex identification of U. thibetanus using non-invasive samples (e.g., hair and/or feces) is potentially valuable. In this study, a non-invasive molecular method for sex identification of U. thibetanus samples collected from various countries was first utilized, and it was based on polymerase chain reaction (PCR) amplification of the amelogenin gene via PCRs. Thirty-three bear DNA samples, extracted not only from blood (n=9) but also from hair (n=18) and feces (n=6), were used. We performed sex-specific PCR amplifications of the amelogenin gene using a primer set, SE47 and SE48. The primer set could successfully amplify a single X-specific band for females and both X- and Y-specific bands for males from all blood (100%) and hair (100%) samples. In addition, the primer set could distinguish the sex of bears in four out of a total of six fecal samples (approximately 67%). This study's findings suggest that this molecular method can be applied to sex identification of Asiatic black bears from various Asian regions using non-invasive samples, such as hair and feces.

• The Plant Pathology Journal
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• 제38권3호
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• pp.194-202
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• 2022

Erwinia amylovora and Erwinia pyrifoliae cause fire blight and black-shoot blight, respectively, in apples and pears. E. pyrifoliae is less pathogenic and has a narrower host range than that of E. amylovora. Fire blight and black-shoot blight exhibit similar symptoms, making it difficult to distinguish one bacterial disease from the other. Molecular tools that differentiate fire blight from black-shoot blight could guide in the implementation of appropriate management strategies to control both diseases. In this study, a primer set was developed to detect and distinguish E. amylovora from E. pyrifoliae by conventional polymerase chain reaction (PCR). The primers produced amplicons of different sizes that were specific to each bacterial species. PCR products from E. amylovora and E. pyrifoliae cells at concentrations of 10⁴ cfu/ml and 10⁷ cfu/ml, respectively, were amplified, which demonstrated sufficient primer detection sensitivity. This primer set provides a simple molecular tool to distinguish between two types of bacterial diseases with similar symptoms.

• 생명과학회지
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• 제27권12호
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• pp.1486-1493
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• 2017

된장은 콩 발효식품으로 주원료인 콩류에 Bacillus subtilis, Rizopus, Mucor와 Aspergillus species를 접종하여 발효시킨 메주를 소금물과 혼합하여 숙성 시킨 한국의 전통적인 발효식품이다. 본 연구에서는 동물실험을 통하여 검정콩 된장의 항비만 효과를 확인하였다. 항비만 효과의 확인은 혈중 TG, TC, 아디포넥틴과 렙틴의 레벨을 측정함과 동시에 지방합성에 관여하는 전사인자인 SREBP-1c과 PPAR-g의 mRNA와 단백질 발현 정도를 측정하였다. 고지방 식이에 검정콩 된장을 첨가한 그룹에서는 고지방식이로 인해 증가된 체중을 유의적으로 감소시킴을 확인하였다. 혈중 중성지방, 콜레스테롤과 렙틴의 레벨은 고지방식이를 섭취한 마우스에 비하여 검정콩 된장을 섭취한 마우스에서 감소하였으며 아디포넥틴의 분비량은 유의적으로 증가하였다. 이러한 결과가 지방 생성의 억제로부터 유도되는지를 조사하기 위하여 지방 합성에 관여하는 전사인자인 SREBP-1c과PPAR-g의 mRNA양과 단백질 발현을 측정한 결과 검정콩 된장을 섭취한 마우스에서 현저하게 감소하는 것을 확인하였다. 이러한 결과는 검정 콩 된장의 섭취가 지방대사와 지방 전사 인자의 활성을 감소시킨다는 것을 확인함으로써 검정콩 된장이 비만의 예방과 진행을 개선시킬 수 있음을 증명하였다.

• International Journal of Advanced Culture Technology
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• 제11권3호
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• pp.83-88
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• 2023

The increasing global average temperature and the emergence of various abnormal climate phenomena are already being experienced in reality. The problems arising from climate change are expanding and becoming catastrophic, despite the efforts of various organizations to prevent them. In order to avoid climate issues from becoming black elephants, we conducted interviews with emergency planning officer from various institutions to identify potential X-events caused by climate change. The results of analyzing the anticipated X-events by these emergency planning officer revealed a chain of ripple effects associated with their occurrence. This implies that once an X-event happens, its influence is broader and more significant. Through this study, we aim to share the understanding of the ripple effects of climate X-events with many people, raising awareness of the severity of climate issues. We hope that this will serve as a starting point for more institutions, individuals, and nations to make efforts in resolving climate problems, turning X-events into opportunities rather than crises.