• 제목/요약/키워드: New host

검색결과 1,040건 처리시간 0.029초

Notable mutations of porcine parvovirus 1 and 4 circulating in commercial pig farms in South Korea

  • Beomsu Park;Jihyeon Hong;Jongsu Jun;An Kook Choi;Choi Kyu Park;Young Soo Lyoo
    • 대한수의학회지
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    • 제64권1호
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    • pp.4.1-4.5
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    • 2024
  • In this study, almost complete genomic sequences of porcine parvovirus (PPV)1 and PPV4 circulating in commercial pig farms in South Korea were obtained and analyzed. Important mutations that may be precursors to host changes, such as premature stop codons of PPV1 and frameshift mutations of PPV4, were observed in these sequences. A 27a-like strain of PPV1, known to show a lack of cross- neutralization against existing commercial vaccine strains, was identified by phylogenetic analysis. Given the active genetic evolution, the additional precursors to host changes and emerging new genotypes of PPVs need to be monitored through continuous sampling and genetic analysis.

감귤원과 그 주변 기주식물에서 볼록총채벌레의 연중발생 양상 (Annual Occurrent Pattern of Scirtothrips dorsalis (Thysanoptera: Thripidae) on Citrus Trees and Surrounding Host Plants)

  • 송정흡;김창석;양영택;홍순영;이신찬
    • 한국응용곤충학회지
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    • 제52권3호
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    • pp.185-191
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    • 2013
  • 제주지역 노지감귤에서 2007년부터 볼록총채벌레 Scirtothrips dorsalis Hood에 의한 피해가 증가하고 있으나 시기별 발생특성에 관한 연구는 명확하지 못한 실정이다. 본 연구에서는 감귤원 주변에 분포하고 있는 볼록총채벌레의 기주식물 종류와 이와 연관된 발생특성을 구명하였다. 감귤원 주변에서 조사된 볼록총채벌레의 기주식물은 수목류 23과 39종, 초본류 10과 15종으로 총 32과 54종이었다. 조사된 기주식물 중 볼록총채벌레 제1세대 발생과 관련된 것은 인동덩굴과 사위질빵, 송악, 아왜나무였으며, 이들 식물에 월동성충이 3월 하순~4월 상순에 산란하여 성충이 4월 하순~5월 하순에 발생되는 것으로 추정되었다. 감귤 피해와 관련된 기주식물은 예덕나무와 동백나무 그리고 사위질빵, 계요등, 거지덩굴 같은 덩굴성 식물이었다. 황색끈끈이트랩을 감귤나무와 감귤원 경계에 설치하여 볼록총채벌레의 시기별 발생밀도를 조사한 결과 비슷한 발생양상을 보였으며, 연간 7세대를 경과하는 것으로 추정되었다. 감귤 열매에 피해를 주는 시기는 6월 하순~7월 상순과 8월 하순~9월 상순으로 어린 열매와 성숙 초기 2회에 걸쳐 피해를 주며, 이는 각각 볼록총채벌레 제 3세대와 제 6세대 성충 발생 최성기와 일치하였다. 볼록총채벌레 발생밀도는 기주식물의 새순 발생량에 따라 차이가 컸으며, 감귤원 주변 기주식물에서 번식한 후 감귤나무로 이동하여 피해를 주는 것으로 나타났다.

신 국제물류환경과 인적관리의 중요성 (The Importance of Human Resource Management in New International Logistics Environment)

  • 김진환
    • 한국항만경제학회지
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    • 제17권1호
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    • pp.113-128
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    • 2001
  • The modem world has brought a wave of changes, not the least of which is globalization or what is often referred to as the "borderless society." In recent times, changes in the global business environment, such as trade deregulation and advances in technology, are challenging us to find new ways of thinking about and coping with these new forces. The field of global logistics has encountered a host of paradigm shifts as well. Therefore, it is critical that managers involved in international logistics take into account perceptional swift or at least understand the value of fully utilizing information. The appropriate management of human resources is a key factor in dealing with not only new information technology, but also shifts in the business environment. In particular, it will be important for Korea's logistics managers at international logistics companies to continually work to develop themselves, as they must carry out a critical role in global supply chain management. If they fail to take heed of the demand's of the new environment, the competitiveness of Korean enterprises in international logistics will suffer severely.

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Environmental effects in the stellar populations of Compact Elliptical galaxies

  • Kim, Suk;Jeong, Hyunjin;Lee, Youngdae;Joo, Seok-Joo;Lee, Jaehyun;Sung, Eon-Chang
    • 천문학회보
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    • 제42권1호
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    • pp.30.2-31
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    • 2017
  • Compact elliptical (cE) galaxies are in a rare class of stellar systems characterized by high stellar densities, small sizes, high velocity dispersion, and high metallicity corresponding to elliptical galaxies. cE galaxies have been observed around massive galaxies, so they could be formed under strong influences of tidal stripping and truncation. However, the recent discovery of isolated cE galaxies requires the need of new formation scenarios. We aim at finding cE galaxies in various environments using SDSS DR12, and studying stellar population of cEs as function of environments. Based on the typical properties of cE galaxies, we selected cE candidates by restricting that low-luminosity Mg > 19.5 mag, small sizes Re < 700 pc, and high velocity dispersions ${\sigma}$ > $60kms^{-1}$. Since effect radii of cE candidates are mostly smaller than the seeing size of SDSS photometry, we calculated the effective radius by fitting a Sersic profile. In addition, we assumed that host galaxies have brightness with Mr < -21 mag, and an environmental parameter is computed as distances between cE galaxies and host-galaxies. We found 112 cE galaxies at z < 0.05, which have high sersic indices (mean value is 5.2) similar to the typical massive elliptical galaxies. Mgb values of cE galaxies increase as the distances from the host galaxies decrease. Especially, for cEs close to the host galaxies (NcE; $D_{host}$ < 300 pc), the Mgb values are similar to those of massive elliptical galaxies, which is consistent with the previous studies. On the other hand, cE galaxies distant from the host galaxies (DcE; Dhost >300 pc) have lower Mgb values than the conventional cE. The Mgb values follow the ${\sigma}$-Mgb relation of elliptical galaxies, and are connected to its faint end. This can be explained as a result of different merger histories for differing environments. For example, NcE galaxies are formed by tidal stripping by massive galaxies as suggested by previous studies, but DcE galaxies could be linked with high-redshift spheroids (e.g. red nuggets) which have not evolved into present-day elliptical galaxies because of the environmental influences.

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뉴칼레도니아의 해산 무척추동물에 공생하는 요각류(갑각강) (Copepods (Crustacea) Associated with Marine Invertebrates from New Caledonia)

  • 김일회
    • Animal Systematics, Evolution and Diversity
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    • 제spc4호
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    • pp.1-167
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    • 2003
  • 남태평양에 있는 뉴칼레도니아의 무척추동물에 공생하는 요각류를 기록하였다. 3신속 (Ruhtra, Pterioidicola, Pachysericola), 30신종이 포함되어 있으며, 이들은 천장입요각목 및 대롱입요각목 내의 다음과 같은 속에 해당된다: Anchimolgus속 (5신종), Jamescookina속 (2신종), Odontomologus속 (2신종), Schedomolgus속 (3신종), Scyphuliger속 (5신종), Critomolgus속 (3신종), Doridicola속 (1신종), Paramolgus속 (2신종), 신속 Pterioidicola (1신종), 과의 위치가 불분명한 신속 Ruhtra (1신종), Asteropontius속 (5신종). 뉴칼레도니아의 미기록종과 새로운 숙주에 대해서도 기록하였다. 지금까지 기록된 뉴칼레도니아산 공생성 요각류 251종과 이들의 무척추동물 숙주 163종의 목록도 제시하였다.

수직 감염된 B형 간염 바이러스 Promoter 유전자의 변이 분석 (Sequence Variations of Hepatitis B Virus Promotor Regions in Vertically Transmitted Mother-child Pairs)

  • 이충원;한영나;이정화;이광철;하영미
    • Pediatric Gastroenterology, Hepatology & Nutrition
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    • 제5권1호
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    • pp.39-50
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    • 2002
  • Hepatitis B viral infection which affect about 10% of Korean population manifests asymptomatic carrier, chronic hepatitis and liver cirrhosis and even associates with hepatocellular carcinoma. Clinical manifestations induced by hepatitis B virus vary depending on the degree of immune response by cytotoxic T cells against viral epitope-presenting liver cells. Since hepatitis B virus presents high rate of mutaton that might change the presented epitope and eventually alter immune response, viral mutations, especially in promoters and enhancers, have an important implication in hepatic inflammation and viral replication. To identify mutations related to the hepatic inflammation, we investigated sequence variations of hepatitis B viral promotor regions in the presence or absence of symptoms in hepatitis B carriers. For this, sera from persistently hepatitis B virus-infected mother-child pairs were collected. After PCR amplifiation of all hepatitis B viral promoters (C promoter, S1 promoter, S2/S promoter, X promoter) using serum DNA from each pair, viral promotors were sequenced by automatic sequencer and then sequence data were analyzed by ClustalW. In most cases, the dominant type of maternal virus was transmitted to the child. However, in some children, some new host specific viral variants could be observed in Cp, S1p and S2/Sp. The mutations in C promoter did not seem to be vertically transmitted but arose in new host independently after the wild type had been transmitted. Enhancer I containing X promoter revealed high host specific variations as has been reported before. Two S promoters, S1p and S2/Sp, have shown some point mutations in children, but no deletion mutations were detected as in chronic hepatitis patients in whom deletion mutations are frequently found. In conclusion, the children with the vertically transmitted hepatitis B virus mostly retain the dominant type virus that had been transmitted. However, host specific variants tended to accumulate over time, possibly as clinical symptoms develop.

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한국수산업의 해외진출전략에 관한 연구 (Foreign Entry Strategies for Korean Fishery Firms)

  • 김회천
    • 수산경영론집
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    • 제15권1호
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    • pp.131-153
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    • 1984
  • Fishery resources are still abundant compared with other resources and the possibility of exploitation is probably great. The Korean fishery industry has grown remarkably since 1957, and Korea is ranked as one of the major fishery countries. Its of fishery products reached the 9th in the world and the value of exports was 5th in 1982. But recently a growth rate has slowed down, due to the enlargement of territorial seas by the declaration of the 200 mile, Exclusive Economic Zone, the tendency to develop fishery resources strate-gically in international bargaining, the change in function of the international organizations, the expansion of regulated waters, the illegal arrest of our fishing boats, the rapid rise in oil prices, and the fall in fish prices, the development of fishery resources as a symbol of nationalism, the fishing boats decreptitude, the rise of crew wages, regulations on fishing methods, fish species, fishing season, size of fish, and mesh size, fishing quotas and the demand of excessive fishing royalties. Besides the the obligation of coastal countries, employing crews of their host countries is also an example of the change in the international environment which causes the aggravation of foreign profit of fishing firms. To ameliorate the situation, our Korean fishery firms must prepare efficient plans and study systematically to internationalize themselves because such existing methods as conventional fishing entry and licence fishing entry are likely to be unable to cope with international environmental change. Thus, after the systematic analysis of the problem, some new combined alternatives might be proposed. These are some of the new schemes to support this plan showing the orientation of our national policy: 1. Most of the coastal states, to cope with rapid international environmental change and to survive in the new era of ocean order, have rationalized their higher governmental structure concerning the fishery industries. And the coastal countries which are the objectives of our expecting entry, demand excessive economic and technical aid, limit the number of fishing boats’entry and the use of our foreign fishing bases, and regulate the membership of the international fishery commissions. Especially, most of the coastal or island countries are recently independent states, which are poorer in national budget, depend largely on fishing royalties and licence entry fees as their main resources of national finance. 2. Alternatives to our entry to deep sea fishing, as internationalization strategies, are by direct foreign investment method. About 30 firms have already invested approximately US $ 8 million in 9 coastal countries. Areas of investment comprise the southern part of the Atlantic Ocean, the Moroccan sea and five other sea areas. Trawling, tuna purse seining and five other fields are covered by the investment. Joint-venture is the most prominent method of this direct investment. If we consider the number of entry firms, the host countries, the number of seas available and the size of investment, this method of cooperation is perhaps insufficient so far. Our fishery firms suffer from a weakness in international competitive ability, an insufficiency of information, of short funds, incompetency in the market, the unfriendliness of host coastal countries, the incapability of partners in joint-ventures and the political instability of the host countries. To enlarge our foreign fishing grounds, we are to actively adopt the direct investment entry method and to diversity our collaboraboration with partner countries. Consequently, besides proper fishing, we might utilize forward integration strategies, including the processing fied. a. The enterprise emigration method is likely to be successful in Argentina. It includes the development of Argentinian fishing grounds which are still not exploited in spite of abundant resources. Besides, Arentina could also be developed as a base for the exploitation of the krill resources and for further entries into collaboration with other Latin American countries. b. The co-business contract fishing method works in American territorial seas where American fishermen sell their fishery products to our factory ships at sea. This method contributes greatly to obtaining more fishing quotas and in innovation bottom fishing operation. Therefore we may apply this method to other countres to diffuse our foreign fishing entry. c. The new fishing ground development method was begun in 1957 by tuna long-line experimental fishing in the Indian Ocean. It has five fields, trawling, skipjack pole fishing and shrimp trawling, and so on. Recently, Korean fisheries were successful in the development of the Antarctic Ocean krill and tuna purse seining. 3. The acceleration of the internationalization of deep sea fishing; a. Intense information exchange activities and commission participation are likely to be continues as our contributions to the international fishery organizations. We should try to enter international fishery commissions in which we are not so far participating. And we have to reform adequately to meet the changes of the function of the international commissions. With our partner countries, we ought to conclude bilateral fishery agreements, thus enlarging our collaboration. b. Our government should offer economic and technical aids to host countries to facilitate our firms’fishery entry and activities. c. To accelerate technical innovation, our fishery firms must invest greater amount in technical innovation, at the same time be more discriminatory in importing exogeneous fishery technologies. As for fishing methods; expanded use of multi-purpose fishing boats and introduction of automation should be encuraged to prevent seasonal fluctuations in fishery outputs. d. The government should increases financial and tax aid to Korean firms in order to elevate already weak financial structure of Korean fishery firms. e. Finally, the government ought to revise foreign exchange regulations being applied to deep sea fishery firms. Furthermore, dutes levied on foreign purchaed equipments and supplies used by our deep sea fishing boats thould be reduced or exempted. when the fish caught by Korean partner of joint-venture firms is sold at the home port, pusan, import duty should be exempted.

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외래기생봉 권연벌레살이금좀벌(국명신칭), Anisopteromalus apiovorus Rasplus (Hymenoptera: Pteromalidae)의 한국 내 신 분포 기록 (First Record on the Exotic Parasitoids Anisopteromalus apiovorus Rasplus (Hymenoptera: Pteromalidae) in Korea)

  • 조봉균;김일권;윤춘식;김형곤;정선우
    • 한국환경과학회지
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    • 제23권8호
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    • pp.1463-1468
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    • 2014
  • An exotic parasitic wasp Anisopteromalus apiovorus of Pteromalidae was newly recorded in Korea. Specimens of this species have been collected in Gimhae of Korea since 2012. External morphology of this species was described in detail and diagnostic differences of this species from the related species and the host insect were also given. The funicle segments of female antennae are 1.2 to 1.5 times longer than those of Anisopteromalus calandrae, an sister species. Body color is gold-glossy black and with dense creamy-white hairs on the surface. This exotic species has been originated from the African continent including Democratic Republic of Congo and Cote d'Ivoire, and then intruded into other countries, for instance, Korea. This is the first distribution record of this species except the country of origin after original description as a new species. Although little is known about the life history or ecology of this species, we found that a new host of this small parasitic wasp is Lasioderma serricorne of coleoptera through present study. And this species possibly be a new agent of biological control for economic pests. It was presumed that the invasion of Anisopteromalus apiovorus into Korea was prior to November of 2012.

Improvement of Handoff-state and QOS in Wireless Environment

  • Jeong, You-Sun;Choe, U-Gin
    • Journal of information and communication convergence engineering
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    • 제8권1호
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    • pp.1-5
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    • 2010
  • In this paper, we propose for improving QoS in wireless micro cellular network using Cellular-IP/PRC(Paging Route Cache) with Paging Cache and Route Cache in Cellular-IP and propose for performance of realtime and non-real time handoff service using Handoff state machine Paging Route Cache. Although the Cellular-IP/PRC technology is devised for mobile internet communication, it bas its vulnerability in frequent handoff environment. On the other hand, Cellular IP combines the capability of cellular networks to provide high performance handoff and efficient location management of active and idle mobile users with the inherent flexibility, robustness and scalability found in IP networks. Also Cellular-IP/PRC use semi-soft handoff. During semi-soft hand off a mobile host may be in contact with either of the old and new base stations and receive packets from them. Packets intended to the mobile node are sent to both base stations and buffered, so when the mobile host eventually moves to the new location it can continue to receive packets without interruption. It should be suitable for realtime service such as multimedia traffic. But, much waste of resource will occur in this method, especially for non-real time services such as FTP and E-mail. Therefore, a new algorithm that performs different handoff according to characteristic of each traffic by use of reserved field in IP packet is proposed in this thesis. This hand off state machine using differentiated handoff improves quality of services in Cellular-IP/PRC. Suggested algorithm shows better performance than existing technology in wireless mobile internet communication environment. Matlab simulation results are improving QoS, show call drop and call blocking provided to Paging Router Cache during handoff state machine in Cellular-IP/PRC.

동결건조한 산양뼈의 개이식 효과 (Effectiveness of Transplantation by Freeze-Dried Bone of Goat to Dogs)

  • 최인혁;이종일
    • 한국임상수의학회지
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    • 제15권2호
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    • pp.442-449
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    • 1998
  • Freeze-dried cortical bones of the goat were transplanted to the experimental fibular defect of 10 dogs for valuating the possibility of xenogeneic bone implantation and the specificity of BM(Bone Morphogenetic Protein). The . freeze-dried cortical bone eliminated antigens and defatted with chloroform and methanol were freeze-dried at $-80{\circ}C$ for preservation of BMP and then sterilized with 50 gas and storaged in room temperature. Ten freeze-dried cortical implants of the goat were transplanted in experimentally defected regions of bilateral fibula of 5 dogs in clinically normal. The transplanted region had been radiographed for observing state of bone union and BALPOone Alkaline Phosphatase) in the serum of the host was measured for valuating activity of oteoblast per 2 week-interval after transplant procedures. New bone formation had been observed early in one of ten regions around implants about the same time as autoimplant regions. It was incorporated with its host bone during 4-12 weeks after transplantation. In another 2 cases of 2 dogs, new bone formation and absorption of implant had been observed from 4 weeks but they were not incorporated completely until 20 weeks. The rest of the freeze-dried bone implants, 7 cases of 4 dogs had not been observed new bone formation nor absorption of implants. The freeze-drying method for implants means to not influence bone incorporation. Although less of union percentages the union form of this experiment were similar to alloimplantation and it may mean to block immunity reaction that disturbs the bone induction by BMP. It demonsknted that the possibility of the xenogenous bone implantation is recognized by reason of the low specificity of BMP between goat and dog.

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