• Title/Summary/Keyword: CAS-4

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A Study on Appropriate Device Authentication Scheme Based PKI for Exchangeable CAS (XCAS) (다운로드형 수신제한시스템(XCAS)에 적합한 PKI기반의 장치 인증기법에 대한 연구)

  • Hwang, Yu-Na;Jeong, Han-Jae;Won, Dong-Ho;Kim, Seung-Joo
    • The KIPS Transactions:PartC
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    • v.17C no.4
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    • pp.347-360
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    • 2010
  • A condition access system (CAS) refers to a hardware-based system that allows only authenticated users to have access to contents. The CAS has many disadvantages found in that in the replacement of multiple service operator (MSO) a set-top box should be also changed and the smart-card often causes malfunction. To deal with the problems, exchangeable CAS (XCAS) was developed in 2009. However, in the XCAS, no method to authenticate a proper set-top box has been put forward. In this paper, we propose a novel program for set-top authentication in the XCAS. Additionally, we offer a format of certificate of authentication, and procedures of issuing the certificate for broadcasting services suitable for the XCAS. The technical method of authentication a set-top box that will be discussed is of high efficiency since in the MSO it requires only two subjects to communicate during the authentication in the MSO.

Modification of ginsenoside saponin composition via the CRISPR/Cas9-mediated knockout of protopanaxadiol 6-hydroxylase gene in Panax ginseng

  • Choi, Han Suk;Koo, Hyo Bin;Jeon, Sung Won;Han, Jung Yeon;Kim, Joung Sug;Jun, Kyong Mi;Choi, Yong Eui
    • Journal of Ginseng Research
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    • v.46 no.4
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    • pp.505-514
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    • 2022
  • Background: The roots of Panax ginseng contain two types of tetracyclic triterpenoid saponins, namely, protopanaxadiol (PPD)-type saponins and protopanaxatiol (PPT)-type saponins. In P. ginseng, the protopanaxadiol 6-hydroxylase (PPT synthase) enzyme catalyses protopanaxatriol (PPT) production from protopanaxadiol (PPD). In this study, we constructed homozygous mutant lines of ginseng by CRISPR/Cas9-mediated mutagenesis of the PPT synthase gene and obtained the mutant ginseng root lines having complete depletion of the PPT-type ginsenosides. Methods: Two sgRNAs (single guide RNAs) were designed for target mutations in the exon sequences of the two PPT synthase genes (both PPTa and PPTg sequences) with the CRISPR/Cas9 system. Transgenic ginseng roots were generated through Agrobacterium-mediated transformation. The mutant lines were screened by ginsenoside analysis and DNA sequencing. Result: Ginsenoside analysis revealed the complete depletion of PPT-type ginsenosides in three putative mutant lines (Cr4, Cr7, and Cr14). The reduction of PPT-type ginsenosides in mutant lines led to increased accumulation of PPD-type ginsenosides. The gene editing in the selected mutant lines was confirmed by targeted deep sequencing. Conclusion: We have established the genome editing protocol by CRISPR/Cas9 system in P. ginseng and demonstrated the mutated roots producing only PPD-type ginsenosides by depleting PPT-type ginsenosides. Because the pharmacological activity of PPD-group ginsenosides is significantly different from that of PPT-group ginsenosides, the new type of ginseng mutant producing only PPD-group ginsenosides may have new pharmacological characteristics compared to wild-type ginseng. This is the first report to generate target-induced mutations for the modification of saponin biosynthesis in Panax species using CRISPR-Cas9 system.

Current status of CRISPR/Cas9 base editor technologies and their applications in crop precision breeding

  • Kim, Rigyeong;Song, Jaeeun;Ga, Eunji;Min, Myung Ki;Lee, Jong-Yeol;Lim, Sun-Hyung;Kim, Beom-Gi
    • Korean Journal of Agricultural Science
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    • v.46 no.4
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    • pp.885-895
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    • 2019
  • Plant biotechnologists have long dreamed of technologies to manipulate genes in plants at will. This dream has come true partly through the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9 technology, which now has been used to edit genes in several important crops. However, there are many restrictions in editing a gene precisely using the CRISPR/Cas9 technology because CRISPR/Cas9 may cause deletions or additions in some regions of the target gene. Several other technologies have been developed for gene targeting and precision editing. Among these, base editors might be the most practically and efficiently used compared to others. Base editors are tools which are able to cause a transition from cytosine into thymine, or from adenine into guanine very precisely on specific sequences. Cytosine base editors basically consist of nCas9, cytosine deaminase, and uracil DNA glycosylase inhibitor (UGI). Adenine base editors consist of nCas9 and adenine deaminase. These were first developed for human cells and have since also been applied successfully to crops. Base editors have been successfully applied for productivity improvement, fortification and herbicide resistance of crops. Thus, base editor technologies start to open a new era for precision gene editing or breeding in crops and might result in revolutionary changes in crop breeding and biotechnology.

Two New Species of Placolecis (Lichenized Ascomycota) from China

  • Yin, An Cheng;Wang, Xin Yu;Liu, Dong;Zhang, Yan Yun;Yang, Mei Xia;Li, Li Juan;Wang, Li Song
    • Mycobiology
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    • v.47 no.4
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    • pp.401-407
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    • 2019
  • Two new species of the lichen genus Placolecis are discovered in China, namely P. kunmingensis An. C. Yin & Li S. Wang and P. sublaevis An. C. Yin & Li S. Wang. The new combination P. loekoesiana (S.Y. Kondr., Farkas, J.J. Woo & Hur) An. C. Yin is proposed. Placolecis kunmingensis is characterized by having simple, spherical or ellipsoid, hyaline spores, and pear-shaped pycnidia; while P. sublaevis can be distinguished by its thallus forming larger aggregations with slightly flattened lobes at the thallus margin, and urn-shaped pycnidia. Descriptions, a phylogenetic tree and a key are provided for all the known Placolecis species in China.

A rapid and quantitative fluorescent microsphere immunochromatographic strip test for detection of antibodies to porcine reproductive and respiratory syndrome virus

  • Wei, Yanqiu;Yang, Baozhi;Li, Yunlong;Duan, Yongcheng;Tian, Deyu;He, Baoxiang;Chen, Chuangfu;Liu, Wenjun;Yang, Limin
    • Journal of Veterinary Science
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    • v.21 no.4
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    • pp.68.1-68.8
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    • 2020
  • A fluorescent microsphere-based immunochromatographic strip test (FICT) was developed for the rapid, sensitive, and quantitative detection of porcine reproductive and respiratory syndrome virus (PRRSV) antibodies at the pen-side. The assay was based on the formation of a sandwich immune-complex (anti-pig IgG-PRRSV antibodies-NSP7/N), which was validated by a comparison with IDEXX-ELISA using 3325 clinical specimens. The diagnostic specificity, sensitivity, and accuracy of FICT were 97.28, 93.41, and 94.95%, respectively. FICT showed a good correlation with the virus neutralization assay. Overall, a promising pen-side diagnostic tool was developed for the rapid and quantitative detection of PRRSV antibodies within 15 min.

Photosensitization Effect and Structure-Activity on Mutagenic Potential by 4-(Nitrobenzyl)Pyridine (4-NBP) Test, of Epoxides, Olefins and Alkylating Agents (4-(Nitrobenzyl)Pyridine에 의한 에폭시드 및 알킬화합물의 변이원성 잠재력에 대한 구조활성 및 광화학효과의 연구)

  • 김재현;엄애선
    • Journal of Environmental Health Sciences
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    • v.27 no.2
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    • pp.43-50
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    • 2001
  • This paper reviews the results of a series of efforts to develop structure-activity models for slow-reacting chemicals and olefins whose toxicity may be enhanced by the ultraviolet radiation. Photoinduced toxicity of 14 compounds was found to be a different result of competing factors of structure, having carbon-carbon double bonds. To mimic the biological consequences of photooxidative damage in mammalian cells, the photochemical mutagenicith of 14 chemicals was tested in the CAS. Simple olefins were photochemically mutagenic or carcinogenic with irradiation, increasing the alkylating activity from zero level to 0.87(abs/gram) for styrene, 0.25 for 1-butene, 0.11 for 1-hexene, respectively, whereas no photochemical mutagenicity was observed with 1-octene in the absence of the CAS. Oxide compounds, however, showed a decreasing trend of photoalkylating activities in the presence or absence of the CAS. We found that the structure-activity relationship was not applicable to our data.

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A Study on Pre-evaluation of Tree Species Classification Possibility of CAS500-4 Using RapidEye Satellite Imageries (농림위성 활용 수종분류 가능성 평가를 위한 래피드아이 영상 기반 시험 분석)

  • Kwon, Soo-Kyung;Kim, Kyoung-Min;Lim, Joongbin
    • Korean Journal of Remote Sensing
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    • v.37 no.2
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    • pp.291-304
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    • 2021
  • Updating a forest type map is essential for sustainable forest resource management and monitoring to cope with climate change and various environmental problems. According to the necessity of efficient and wide-area forestry remote sensing, CAS500-4 (Compact Advanced Satellite 500-4; The agriculture and forestry satellite) project has been confirmed and scheduled for launch in 2023. Before launching and utilizing CAS500-4, this study aimed to pre-evaluation the possibility of satellite-based tree species classification using RapidEye, which has similar specifications to the CAS500-4. In this study, the study area was the Chuncheon forest management complex, Gangwon-do. The spectral information was extracted from the growing season image. And the GLCM texture information was derived from the growing and non-growing seasons NIR bands. Both information were used to classification with random forest machine learning method. In this study, tree species were classified into nine classes to the coniferous tree (Korean red pine, Korean pine, Japanese larch), broad-leaved trees (Mongolian oak, Oriental cork oak, East Asian white birch, Korean Castanea, and other broad-leaved trees), and mixed forest. Finally, the classification accuracy was calculated by comparing the forest type map and classification results. As a result, the accuracy was 39.41% when only spectral information was used and 69.29% when both spectral information and texture information was used. For future study, the applicability of the CAS500-4 will be improved by substituting additional variables that more effectively reflect vegetation's ecological characteristics.

Historical Introduction of Japanese Wild Mice, Mus musculus, from South China and the Korean Peninsula

  • Nunome, Mitsuo;Suzuki, Hitoshi;Moriwaki, Kazuo
    • Animal Systematics, Evolution and Diversity
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    • v.29 no.4
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    • pp.267-271
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    • 2013
  • In Japan, the wild house mouse Mus musculus consists of two lineages, one from Southeast Asia (Mus musculus castaneus; CAS) and one from northern Eurasia (Mus musculus musculus; MUS). However, the exact origins of the parental lineages are unclear. A recent work using mitochondrial sequences revealed that Japanese CAS and MUS are closely related to haplotypes from South China and the Korean Peninsula, respectively. Recent phylogeographic analyses using nuclear gene sequences have also confirmed a close relationship between Japan and Korea in the MUS component. However, the Japanese CAS components in the nuclear genome are likely to be unique and to differ from those of other CAS territories, including South China. Although the origins are still unresolved, these results allow us to conclude that two areas of the continent, South China and the Korean Peninsula, are the primary source areas of Japanese wild mice and suggest pre-historical introductions associated with certain historical agricultural developments in East Asia.

Near-infrared Spectroscopy of Metal-enriched Supernova Ejecta in Cassiopeia A

  • Lee, Yong-Hyun;Koo, Bon-Chul
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.1
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    • pp.44.4-44.4
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    • 2019
  • The supernova remnant Cassiopeia A (Cas A) provides a unique opportunity to observe the fine details of the explosion of core-collapse supernova (SN). Previous optical and near-infrared (NIR) observations of Cas A have shown that the spatial distribution of the metal-enriched SN ejecta is very complicated, indicating that the SN explosion should have been asymmetric and turbulent, especially near the core. Recently, we obtained a long-exposure (~10 hr) image of Cas A by using the UKIRT 3.6-m telescope with a narrow-band filter centered at [Fe II] 1.644 um emission. This 'deep [Fe II] image' provides an unprecedented panoramic view of Cas A, revealing the distribution of dense SN ejecta over the entire remnant. We have carried out NIR multi-object spectroscopic observations of the dense ejecta knots in the northeastern (NE) and eastern (E) outer regions of the remnant using the MMIRS attached on the MMT 6.5-m telescope. A total of 67 ejecta knots are detected. By analyzing their spectra, we have found that the knots in the NE area show strong [S II]/[S III] and [Fe II] lines but little or no [P II] line, while those in the E outer region show strong [Fe II] lines but weak [S II]/[S III] lines. In this talk, we present the preliminary results of our NIR spectroscopic observations and discuss the implications.

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