• 제목/요약/키워드: first occurrence

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Etiology and Epidemiology of Clubroot Disease of Chinese Cabbage and Its Management in Korea

  • Kim, Choong-Hoe
    • 한국식물병리학회:학술대회논문집
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    • 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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    • pp.9-12
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    • 2003
  • Clubroot disease of curcifer crops caused by Plasmodiophora brassicae had been first reported in 1920 in Korea, and maintained mild occurrence until 1980s. Since 1990s the disease has become severe in alpine areas of Kyonggi and Kangwon, gradually spread to plain fields throughout the country, and remains as the greatest limiting factor for its production. Researches on the disease has begun in late 1990s in our laboratory after experiencing severe epidemics. Survey of occurrence and etiological and ecological studies have been carried out, particularly, on the pathogen physiology, race identification, quantification of soil pathogen population, host spectrum of the pathogen, and control measures.(중략)

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사례 조사를 통한 백화현상의 특징 및 저감 방안 연구 (The study on characteristic of efflorescence phenomenon and reduction plan through research)

  • 박영민;이희두;이해진;임남기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2002년도 학술논문발표회
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    • pp.1-6
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    • 2002
  • The study offer a suggestion that from result in being a case to efflorescence for decrease a plan: $\circled1$ A efflorescence of concreat a structure will be the prograss plan; In the materials, depress use to the water-sand in the construction, admonish unification of front and rear in the environment, consideration requisite concreat don't the occurrence efflorescence. $\circled2$ Ma sonry building efflorescence establish a ventilation opening and a waterway to ma sonry the times avoid the winter or the rainy season. Ma sonry building efflorescence will be make good among a brick to a brick interval closely mortar. $\circled3$ Tile building, tile of plasticity temperature is appropriate, reduce the deviation, parapet part of efflorescence will be make good closely mortar. A construction material part a meterial developing need Perfection of construction a efflorescence occurrence is the minimum, a plan Part developed so on, composition of a ommection field systematic effort need a efflorescence Prevention a kind of detail.

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냉장고 수축팽창 소음원의 규명과 저감 방법 (Identification and Reduction Method for Refrigerator Contraction and Expansion Noise)

  • 김원진;박성규
    • 한국생산제조학회지
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    • 제22권4호
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    • pp.723-729
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    • 2013
  • The contraction and expansion noise of a refrigerator are investigated, and some effective methods are proposed to reduce the level and occurrence frequency of noise. First, the noise of a refrigerator is measured to estimate the frequency spectrum and occurrence frequency of noise. Second, a sound visualization was conducted using an acoustic camera to determine the location of the noise source. From the results, it was observed that the internal part mainly producing noise was the third shelf in the freezer room. A method to estimate the acceleration on the location of the noise source is introduced to analyze the contraction and expansion noise precisely and accommodate experimental convenience. Noise reduction methods such as the replacement of the existing shelf with glass shelves, adoption of rail slides, and increase of roughness on the contact surface of the shelf are proposed and tested.

개의 잠복고환된 단 고환에서 정상피종과 세르토리 세포종의 동시 발생 (Concurrent Occurrence of Seminoma and Sertoli Cell Tumor in a Dog with Ctyptorchidism and Monorchidism)

  • 조호성;;박남용
    • 한국임상수의학회지
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    • 제21권2호
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    • pp.191-193
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    • 2004
  • A 9-year-old male poodle dog exhibited a white to yellow 3.0$\times$2.0$\times$3.9 cm mass in the left testicle with cryptorchidism and monorchidism. Grossly, necrosis and hemorrhage were observed on the cut surface of the mass. Histopathologically the mass consisted of seminoma and sertoli cell tumor (SCT). Seminoma was characterized with diffuse solitary pattern in which tumor cells had polygonal nuclei and clear cell border. SCT was composed of compact neoplastic cells with small nuclei and indefinite cytoplasm. The tumor was occupied mainly with SCT. SCT and seminoma were observed occasionally in the same lesion. From these results, this case was diagnosed as concurrent seminoma and SCT in the left cryptorchidism and monorchidism. To our knowledge, this is the first report of concurrent occurrence of seminoma and SCT in a dog with cryptorchidism and monorchidism in Korea.

The Occurrence of Kranz Type Species Among the Noxious Weeds on Cultivated Land of Taiwan and their Biochemical Subdivision

  • Lin, Chin Ho;Yin, Shan Tai
    • 한국잡초학회지
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    • 제8권2호
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    • pp.133-140
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    • 1988
  • One hundred and one noxious weeds on cultivated land of Taiwan were investigated for the occurrence of "Kranz" leaf anatomy and activities of PEP carboxylase and $C_4$ acid decarboxylating enzymes : NADP-malic enzyme, NAD-malic enzyme, PEP carboxykinase. Based on the leaf anatomy and a/b chlorophyll ratio, twenty-seven species exhibit "Kranz" type leaf anatomy, and seventy-four species were found without it. Among the species investigated, Digitaria radicosa (Presl) Miq., Leptochloa chinensis (L.) Nees, and Sporobolus fertilis (Steud.) W. D. Clayton in the Gramineae were first recorded as $C_4$ plants. Twenty-sven species of "Kranz" type leaf anatomy, include those of monocotyledon ; sixteen species in Gramineae, six species in Cyperaceae. Those of dicotyledon ; two species each in Euphorbiaceae and Amaranthaceae and one species in Portulacaceae. The subtype of fourteen previously uninvestigated species among twenty-seven species were further determined. The properties of the three decarboxylating enzyme from representative species were also characterized.

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Occurrence of hydropericardium-hepatitis syndrome in broilers and baeksemis raised in Korea

  • Kim, Ki-Seuk;Ha, Jong-Su;Kim, Jin-Hyun
    • 대한수의학회지
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    • 제47권3호
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    • pp.285-290
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    • 2007
  • The occurrence of hydropericardium-hepatitis syndrome was confirmed for the first time in Korea from chickens submitted for diagnosis to our laboratory from broiler and baeksemi farms. Clinical signs included depression, inappetence, ruffled feathers and an increase in mortality. At necropsy, severe hydropericardium and hepatic necrosis was characteristically found. The most remarkable microscopic changes were seen in the liver, including basophilic intranuclear inclusion bodies in the hepatocytes, massive hemorrhages and necrosis in the liver parenchyma. Based on polymerase chain reaction and transmission electron microscopy (TEM), we could identify the fowl adenoviruses as the causative agent of the disease. In the TEM, we observed the presence of a large number of intranuclear virus particles in the hepatocytes. We could also find the PCR amplification of 700 bp DNA from purified hydropericardium-hepatitis syndrome viral DNA.

Occurrence of Chrysanthemum chlorotic mottle viroid in Chrysanthemum(Dendranthema grandiflorum) in Korea

  • Chung, Bong-Nam;Kim, Dong-Chan;Kim, Jeong-Soo;Cho, Jeom-Deog
    • The Plant Pathology Journal
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    • 제22권4호
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    • pp.334-338
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    • 2006
  • Chrysanthemum chlorotic mottle viroid(CChMVd) isolates have been identified from chrysanthemum showing yellow spots or infected without symptom. They were 399-400 nucleotides length of RNA. CChMVd-SSHA6(GenBank accession no. DQ450682) revealed a GAAA to DUUC substitution in positions 82-85 of CChMVd-MSIN34(GenBank accession no. DQ402041). In vitro RNA transcripts with the complete CChMVd sequence were infectious and induced the typical CChMVd infection symptom of yellow spots in chrysanthemum cv. Sharotte. CChMVd caused reduction in growth in some cultivars, whereas some cultivars were not affected. This is the first report on the occurrence of CChMVd in chrysanthemum in Korea.

Occurrence of Stunt Nematode, Tylenchorhynchus claytoni, on Turfgrass in Korea

  • Khan, Zakaullah;Kim, Jeong-Ho;Son, Seon-Hye;Kim, Sang-Gyu;Kim, Young-Ho
    • The Plant Pathology Journal
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    • 제24권4호
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    • pp.474-477
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    • 2008
  • During routine surveys for pest and pathogen incidences at a golf course in 2007, circular to irregular patches of stunted, chlorotic and wilted turfgrass var. Pencross were noticed in Jinhae, Gyeongnam province, Korea. Soil samples collected from those diseased patches of the golf course yielded high population (average 126 nematodes/$100\;cm^3$) of a stunt nematode, Tylenchorhynchus claytoni, which is described and illustrated in this paper with light and scanning electron micrographs. This is the first report on the occurrence of T. claytoni in turfgrass in Korea.

한국에서 벼 흑조위축병의 발생에 대하여 (Studies on the Occurrence of Rice Black-Streaked Dwarf Virus in Korea)

  • 이재열;이순형;정봉조
    • 한국응용곤충학회지
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    • 제16권2호
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    • pp.121-125
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    • 1977
  • 지금까지 우리나라에 발생되지 않았던 새로운 수도 바이러스병인 벼 흑조위축병에 대하여 실시한 확인 및 동정 실험결과는 다음과 같았다. 1) 애멸구(Laodelphax Striatellus FALLEN)가 벼 흑조위축병을 매개하였다. 2) 바이러스의 입자는 구형이었으며 직경은 약60nm이었다. 3) 이 병은 령, 호남지방 및 충청북도에서 발생하였다. 4) 이앙시기가 빠를수록, 바맥일수록 이병주율이 높았다.

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Occurrence of Hydropericardium-Hepatitis Syndrome of Baeksemi and Broiler Raised in Korea

  • Seon, Jeong-Won;Ha, Jong-Soo;Do, Seon-Hee;Kim, Ki-Seuk
    • 한국가금학회:학술대회논문집
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    • 한국가금학회 2005년도 제22차 정기총회 및 학술발표회
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    • pp.80-81
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    • 2005
  • The occurrence of HHS was confirmed for the first time in Korea from chickens submitted for diagnosis to our laboratory from broiler and baeksemi farms. Clinical signs included depression, inappetence, ruffled feathers and a increase in mortality. At necropsy, severe hydropericardium and hepatic necrosis was founded characteristically and the most remarkable microscopic changes were seen in the liver. These included basophilic intranuclear inclusion bodies in the hepatocytes, massive hemorrhages and necrosis in the liver parenchyma. We could also identify fowl adeno-virus(FAV) by polymerase chain reaction(PCR) and electro-microscopic confirmation. Abbreviation: HHS=hydropericardium hepatitis syndrome, EM=electron microscopy, FAV=fowl adenovirus, PCR=polymerase chain reaction.

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