• 제목/요약/키워드: branching pattern

검색결과 95건 처리시간 0.021초

Monosiphonous growth and cell-death in an unusual Bostrychia (Rhodomelaceae, Rhodophyta): B. anomala sp. nov.

  • West, John A.;Loiseaux de Goer, Susan;Zuccarello, Giuseppe C.
    • ALGAE
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    • 제28권2호
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    • pp.161-171
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    • 2013
  • A morphologically distinct lineage within the Bostrychia moritziana-B. radicans species complex is described as a new species. Bostrychia anomala has thalli with branched monosiphonous filaments with apical cell divisions. The species has terminal tetrasporangial stichidia, each subtending cell bearing tetrasporangia with 2 cover cells. Discharged spores divide transversely, the lower cell first forming a narrow rhizoid and the upper cell forming a monosiphonous shoot. Females have subterminal procarps and males have terminal spermatangial stichidia. Carposporophytes are spherical. Isolates in culture show a pattern of cell death not associated with injury, reminiscent of programmed cell death. Bostrychia anomola shows cell death at intervals along the filaments resulting in division of adjacent cells on either side of the dead cell re-joining the filament; cell division of only one adjacent cell resulting in branching at that site; or filaments fragmenting at the cell death point with adjacent cells forming new apical cells, a means of thallus propagation. The cell death pattern could be a method of filament propagation in the mangrove environment where sexual reproduction is rare.

문장의 머리방향 매개변수(headedness parameter)와 공조응사(null anaphor)습득 (Headedness Parameter and the Acquisition of Null Anaphor)

  • 조숙환
    • 인지과학
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    • 제1권1호
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    • pp.145-164
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    • 1989
  • 본 논문은 언어습득 초기단계의 아동이 모국어의 주요분기방향(principal branching direction)에따라 종응사규칙을 습득한다는 최근의 연구결과에 의거한다(Lust,1986).이 연구에 의하면,가령 한국어는 좌행 분기어임을 한국아동은 죄행생략형을 선호할 것이라고 한다.이가설을 시험하기 위해 서울에 거주하는 4:1-9:7의 96명의 아동을 모방유도실험으로 개별연구하였다.문장유형으로는 중복형,우행생략형 및 좌행생략형 등이 이용되었다.실험결과,Lust의 예측과는 달리 좌행분기어인 한국어 습득아동도 우행분기어인 영어습득아동처럼 우행 생략형을 좌행생략형보다 용이하게 일찍 습득하고 있음을 발견하였다.이것은 인간에게 분기방향과 같은 문법적 요소에 상관없이 선행사가 공조응사보다 앞서 언급되는 형태(우행생략형) 를 선호하는 인지적기재가 있음을 시사한다고 사려된다.

한국산 뽕나무버섯균의 종에 관한 연구 (Studies on Korean Species of Armillaria)

  • 성재모;양근주;이현경
    • 한국식물병리학회지
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    • 제10권4호
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    • pp.261-269
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    • 1994
  • One hundred and ninety two isolates of Armillaria were obtained from mycelial fans on infected hosts, rhizomorphs, and single basidiospores or trauma tissue of fruiting bodies. Mating tests showed that two of these isolates were A. mellea, eight were A. tabescens, 20 were A. ostoyae, and 162 were A. gallica. Armillaria ostoyae was mainly isolated from Pinus koraiensis and Qurecus spp., A. tabescens from fruiting bodies on Pinus densiflora and Qurecus spp., and A. gallica from many tree species but not Pinus koraiensis. Armillaria mellea, A. gallica, A. ostoyae and A. tabescens showed distinct protein banding patterns. Mycelial growth and rhizomorph formation was good on basal medium with ethanol added. A. gallica and A. mellea formed many rhizomorphs, but A. ostoyae did not. A. gallica showed the best rhizomorph formation on media with tannic acid and ethanol, but a. mellea formed the most rhizomorphs on gallic acid. Rhizomorphs showed monopodial branching for A. gallica and dichotomous branching for A. ostoyae. Fruiting bodies. formed in the laboratory on sawdust media most abundantly by A. tabescens. In nature, fruit body formation by A. tabescens was from early to mid August. A. ostoyae and A. gallica fruit bodies were formed from early August to late October. While there are common names in Korea for A. mellea and A. tabescens, such as mulberry mushroom relative, no common names are available for A. gallica and A. ostoyae. Therefore, we refer to a. gallica as the Gastrodia mushroom because it has been used to produce Gastrodia and A. ostoyae as the Korean pine mushroom because it is frequently found as mushrooms on Korean pine.

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한국재래산양(韓國在來山羊) 대동맥궁(大動脈弓)의 동맥분지(動脈分枝)에 관한 해부학적(解剖學的) 연구(硏究) (Anatomical Studies on Patterns of Branches of Aortic Arch in Korean Native Goat)

  • 이흥식;이준섭
    • 대한수의학회지
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    • 제24권1호
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    • pp.1-7
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    • 1984
  • This macroscopic observation was performed to investigate the aortic arch and their branches of the Korean native goat. Ten Korean native goats with black hairs ranging in body weight from 15 to 20kg were used. The findings were based on the latex cast of the vessels made by injection of neoprene latex. The results obtained were as follow; 1. The aortic arch of the Korean native goat gave off only one vessel, the Truncus brachiocephalicus. 2. The Truncus brachiocephalicus gave off the A. subclavia sinistra, the A. subclavia dextra and the Truncus bicaroticus. 3. The A. subclavia sinistra gave off the Truncus costocervicalis, the A. cervicalis superficialis and the A. thoracica interna, and continued as the A. axillaris sinistra. 4. The Truncus costocervicalis sinistra arose from the A. subclavia sinistra in all cases and gave off the A. scapularis dorsalis suprema and the A. cervicalis profunda, and continued as the A. vertebralis sinistra. 5. The branching pattern of the A. subclavia dextra was similar to that of the A. subclavia sinistra except the Truncus costocervicalis. The Truncus costocervicalis dextra was arisen together with the A. subclavia dextra in 8 out of 10 cases, while one of the remaining 2 cases arose as the first branch of the A. subclavia dextra and the other was given off directly from the Truncus brachiocephalicus. 6. The Truncus bicaroticus was continued from the Truncus brachiocephalicus after branching off the A. subclavia dextra in 8 out of 10 cases, but the Aa. carotidas communes sinistra and dextra were directly branched from the Truncus brachiocephalicus without forming the Truncus bicaroticus in the remaining 2 cases.

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메밀 전분의 이화학적 특성에 관한 연구 (A Study on the Physicochemical Properties of Buckwheat Starches)

  • 이미숙;손경희
    • 한국식품조리과학회지
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    • 제8권3호
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    • pp.291-296
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    • 1992
  • The physicochernical properties of Korean buckwheat starches were investigated. The results were as follows; 1. Water binding capacity of kangwon hull buckwheat starch was 106.55% and that of Kangwon rice buckwheat was 99.35%. 2. The pattern of change in swelling power of hull buckwheat starch for increasing temperature started to increase at 60$^{\circ}C$ and increased rapidly from 80$^{\circ}C$, and that of rice buckwheat increased slowly from 60$^{\circ}C$ to 90$^{\circ}C$. 3. The ranges of gelatinization temp. of hull buckwheat and rice buckwheat starches were 70~75$^{\circ}C$ and 75~85$^{\circ}C$, respectively. 4. The blue value of hull buckwheat starch and rice buckwheat starch were 6.25 and 0.62, respectively. 5. The alkali number of hull buckwheat starch and rice buckwheat starch were 1.28 and 3.68 respectively. 6. The amylose content of hull buckwheat and rice buckwheat starch were 32.26% and 38.09%. 7. Periodate oxidation of hull buckwheat starch resulted that amylose had me average molecular weight of 103, 004, degree of polymerizatlon of 572 and amylopectin had me degree of branching of 7.64, glucose unit per segment of 13.09, and periodate oxidation of rice buck wheat starch resulted mat amylose had me average molecular weight of 125, 654, degree of polymerization of 698 and amylopectin had degree of branching of 6.59, glucose unit per segment of 15.16.

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페리다이나믹 이론 모델을 이용한 재료의 균열 진전 해석 (Peridynamic Modeling for Crack Propagation Analysis of Materials)

  • 정원준;;이제명
    • 한국전산구조공학회논문집
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    • 제31권2호
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    • pp.105-114
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    • 2018
  • 본 연구에서 페리다이나믹 이론 모델을 이용하여 준정적하중과 동적 하중, 균열전파와 분기균열 패턴 그리고 등방성재료, 직교 이방성 재료의 균열 진전 해석 등 다양한 조건을 고려한 전산 시뮬레이션을 수행하여 그 적합성을 검토하였다. 초기 균열은 없지만 중심에 홀이 있는 등방성 재료, 초기 균열이 존재하는 등방성 및 이방성 재료에 대한 전산 시뮬레이션이 수행되었다. 조정 동적 완화 기법이 사용되어 준정적 하중을 모사하였고, 이방성 재료 해석에서는 고전 연속체 역학과 페리다이나믹의 변형률 에너지를 고려한 균질화 방법이 사용되었다. 균열 전파와 분기 균열이 성공적으로 확인되었으며 파괴 거동의 시작과 그 방향 역시 페리다이나믹 이론으로 확인되었다. 페리다이나믹을 균질화 방법을 사용하여 비교적 복잡한 이방성 재료에 적용한 경우 역시 실험 결과 값과 비교하여 검증하였다.

흉선종의 세포학적 검색 (Cytologic Study of Thymoma)

  • 공구;장세진;이중달
    • 대한세포병리학회지
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    • 제1권1호
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    • pp.36-42
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    • 1990
  • The fluoroscopy-guided fine needle aspiration biopsy has been gaining widespread acceptance as a rapid and effective method to make a pre-operative diagnosis of mediastinal tumors including thymoma, malignant lymphoma, and metastatic carcinoma. Although thymoma is a most common tumor of the superior mediastinum, most cytopathologists are not experted in cytologic diagnosis of this tumor because of limited experience. In order to define the diagnostic cytologic features of thymoma, we have retrospectively reviewed imprinting smears and corresponding tissue sections from four cases of this tumor. All cases revealed an apparent biphasic pattern of epithelial cell clusters and lymphocytes with occasional branching capillary fronds extending from three dimensional epithelial cell clusters. Epithelial cell clusters predominated in one case and lymphocytes in two cases. Mixed epithelial cell and lymphocyte type represented in one of four cases. In the lymphocyte predominant type, the presence of epithelial cell clusters and small mature lymphocytes are helpful features to differentiate from a malignant lymphoma.

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New record of the genus Neodilsea and N. yendoana (Dumontiaceae, Gigartinales) in Korea

  • Kang, Pil Joon;Nam, Ki Wan
    • Journal of Ecology and Environment
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    • 제38권4호
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    • pp.655-661
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    • 2015
  • A marine algal species was collected from the southern coast of Korea. This alga is characterized by a large and cartilaginous thallus, a dichotomous branching pattern, compressed axes, rare proliferations near the apex, and cystocarps protruded toward surface. In a phylogenetic tree based on rbcL sequences, this species nests in the same clade as Neodilsea yendoana as a terminal clade of the genus Neodilsea. The genetic distance between both sequences within the clade was calculated as 0.2% considered to be in the intraspecific range within the genus. Based on the morphological and molecular data obtained in the present study, this Korean species is identified as N. yendoana. This is the first record of the genus Neodilsea and N. yendoana in Korea.

무제한 2차원 절단문제에 대해 개선된 최적-우선 분지한계 해법 (An Improved Best-First Branch and Bound Algorithm for Unconstrained Two-Dimensional Cutting Problems)

  • 윤기섭;방성규;강맹규
    • 한국경영과학회지
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    • 제30권4호
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    • pp.61-70
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    • 2005
  • In this Paper, we develop an improved branch and bound algorithm for the (un)weighted unconstrained two-dimensional cutting problem. In the proposed algorithm, we improve the branching strategies of the existing exact algorithm and reduce the size of problem by removing the dominated pieces from the problem. We apply the newly Proposed definition of dominated cutting pattern and it can reduce the number of nodes that must be searched during the algorithm procedure. The efficiency of the proposed algorithm is presented through comparison with the exact algorithm known as the most efficient.

Primary Intracranial Leptomeningeal Melanomatosis

  • Kim, Do-Hyoung;Choi, Chan-Young;Lee, Chae-Heuck;Joo, Mee
    • Journal of Korean Neurosurgical Society
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    • 제58권6호
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    • pp.554-556
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    • 2015
  • Primary intracranial malignant melanoma is a very rare and highly aggressive tumor with poor prognosis. A 66-year-old female patient presented a headache that had been slowly progressing for several months. A large benign pigmented skin lesion was found on her back. A brain MRI showed multiple linear signal changes with branching pattern and strong enhancement in the temporal lobe. The cytological and immunohiostochemical cerebrospinal fluid examination confirmed malignant melanoma. A biopsy confirmed that the pigmented skin lesion on the back and the conjunctiva were benign nevi. We report a case of primary intracranial malignant melanoma and review relevant literatures.