• Restorative Dentistry and Endodontics
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• 제39권1호
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• pp.45-50
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• 2014

Ambiguity in the root morphology of the mandibular second molars is quite common. The most common root canal configuration is 2 roots and 3 canals, nonetheless other possibilities may still exist. The presence of accessory roots is an interesting example of anatomic root variation. While the presence of radix entomolaris or radix paramolaris is regarded as a typical clinical finding of a three-rooted mandibular second permanent molar, the occurrence of an additional mesial root is rather uncommon and represents a possibility of deviation from the regular norms. This case report describes successful endodontic management of a three-rooted mandibular second molar presenting with an unusual accessory mesial root, which was identified with the aid of multiangled radiographs and cone-beam computed tomography imaging. This article also discusses the prevalence, etiology, morphological variations, clinical approach to diagnosis, and significance of supernumerary roots in contemporary clinical dentistry.

• Animal Systematics, Evolution and Diversity
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• 제20권1호
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• pp.63-71
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• 2004

제주도산 넓적송장벌레의 개체군에 대한 분류학적 위치를 검토하기 위해 한국, 일본 및 중국지역의 105 개체의 성충을 대상으로 수리분석과 수컷 생식기 비교를 실시하였다. 그 결과 ,제주도산 송장벌레 개체군은 지역적 특성의 형태적 차이를 보여 주는 넓적송장벌레(Silpha perforata) Gebler 의 종내 변이로 나타났다.

• 생약학회지
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• 제35권1호통권136호
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• pp.45-51
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• 2004

Panax ginseng C. A. Meyer (Araliaceae) is listed in Shen Nung Pentsao Ching(神農本草經) as the remedy for replenishing the primodial qi(氣), restoring pulse, treating collapse, tonifing the spleen and lag, promoting the production of body fluid to quench thirst, tranquilizing the mind, and improving the function of brain. The prescriptions of In Sam Tang(人參揚) are also recorded in many other Chinese medical books. The identification of the age of Panax ginseng is very important in commercial market as well as in research field. However, any reports about it have not been clearly established yet. To clarify the criterion, the morphological and anatomical characteristics of the roots of various age Panax ginseng cultivated in Korea were studied. The characteristics of cork layer, secretory canal, and vessel were shown to bε useful keys to confirm the age of Panax ginseng.

• 한국언어정보학회지:언어와정보
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• 제11권1호
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• pp.77-96
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• 2007

This paper investigates syntactic variations in English such as Dative Alternation, Particle Inversion, and Object Postposition (Heavy NP Shift) within the framework of Optimality Theory, and shows that the same set of morphological, informational, and processing constraints affect all these variations. In particular, it shows that the variants that used to be regarded as ungrammatical are in fact used fairly often in reality, especially when processing or informational conditions are met, and therefore, grammatical judgment may not be always categorical but sometimes gradient. It is argued that the notion of distance in constraint ranking in stochastic OT can effectively explain the gradience and variability of grammaticality in the variation phenomena.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.471-472
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• 2001

Recently many studies show that genetic characters can be used to provide unambiguous taxonomic discrimination when morphological characters are not practical for routine identification to species level (Bucklin et al., 1996, 1998; Lindeque et al., 1999). The internal transcribed spacer (ITS) regions of the nuclear ribosomal DNA are also one of appropriate markers for species-level studies because it contains sufficient diversity to address intra- and interspecific phylogenetic relationships in invertebrates (Odorico and Miller,1997; Schizas et al., 1999). (omitted)

• Animal Systematics, Evolution and Diversity
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• 제35권2호
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• pp.57-62
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• 2019

Eutima japonica Uchida, 1925, a bivalve-inhabiting hydrozoan was collected for the first time in Korea, associating with Mytilus galloprovincialis. The morphology of male medusae of this hydrozoan is clarified by culture and described as well as other developmental stages. As the present material from Korea is in good accord with that of the northern Japanese form of E. japonica, so the geographical distribution of the northern form of this species is widened, Japan, China and Korea. Green fluorescent protein distribution pattern of this medusa is also described and compared with that of the most related species Eutima sapinhoa Narchi and Hebling, 1975.

• Animal Systematics, Evolution and Diversity
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• 제38권4호
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• pp.274-278
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• 2022

One marine ciliate, Diophrys quadrinucleata Zhang et al., 2020 was newly recorded from South Korea in this study. We provided morphological diagnosis and images of the Korean D. quadrinucleata population. We determined the small subunit ribosomal DNA (SSU rDNA) and cytochrome oxidase subunit I (CO1) sequence data of D. quadrinucleata, and then the sequences were compared with other Diophrys species. Intra-specific variation between the Korean and type (Chinese) populations was identical in the SSU rDNA, while the inter-specific variations between seven Diophrys species were 0.3-3.8% in the SSU rDNA and 12.6-18.2% in the CO1. In this study, we obtained 18S and CO1 data from species with identified morphology. As the importance of securing 18S and CO1 based on morphology increases in current studies, this study will contribute to ciliate studies.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.124-125
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• 2020

In this study, the characteristics of fine aggregates produced according to the jaw crush crushing gap variation were studied and analyzed in terms of recycled aggregates, and the experiments were conducted in terms of grading, density, water absorption, unit volume weight, grain shape. It was shown that the quality of the fine aggregate was affected by the shape of the morphological crushing.

• 식물분류학회지
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• 제53권2호
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• pp.166-169
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• 2023

Carex brevispicula (Cyperaceae) is endemic to Korea and is characterized by constricted achenes, short lateral spikes, and awned staminate and pistillate scales. The species classified in sect. Mitratae occurs throughout South Korea, perennating on mountains and/or rocky slopes under half shadow conditions. Meiotic chromosomes of the species were examined in this study, in which 33 meiotic cells from seven populations were found to be less than 2 ㎛ long with non-constricted chromosomes (n = 34_II). The stable chromosome number may be related to the narrow geographical distribution and/or distinct achene morphology. Further investigations of the distribution, morphological character variation, and chromosome characteristics should be conducted with closely related taxa to understand the derivation of the species and its endemism in Korea.

• 한국자원식물학회지
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• 제16권3호
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• pp.251-256
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• 2003

본 연구는 고려인삼의 집단내의 유전적 변이를 작물학적 특성 및 DNA수준에서 비교하여 인삼품종육성을 위한 기초 자료를 제공하기 위하여 수행한 결과를 요약하면 다음과 같다. 1.개화기는 5월 16일부터 24일 까지 일주일에 걸쳐 개화하였고, 19일과 22일에 개화율이 가장 빈도가 높았다. 2. 줄기 색은 녹색이 13개체, 연자색이 429개체, 자색이 229개체, 진자색이 38개체로 연자색이 가장 많은 분포를 보였으며 한 집단 내에서 다양한 분포를 나타냈다. 3. 초장은 22­68cm의 넓은 범위에 분포하였으며, 20­27cm가 31개체 , 27­34cm가 88개 체, 34­41cm가 219개체 , 41­48cm가 291개체, 48­55cm가 63개체, 55­62cm가 10개체, 62­69cm가 5개체로 다양한 분포를 나타냈다. 4. 뿌리무게는 16­26g이 53개체, 26­36g이 137개체, 36­46g이 385개체, 46­56g이 94개체, 56­66g이 27개체, 66­76g이 9개체, 76­86g이 4개체, 36­46g범위에서 385(57.7%)개체로 가장 많은 분포를 나타내었으며, 16­86g의 범위로 변이 정도가 매우 컸다. 5.662개체를 대상으로 RAPD를 실시한 결과 32개의 프라이머 중 10개 가 재현성이고 다형성인 밴드를 보였다. 10개의 프라이머에서 나타난 전체 밴드수는 109개였으며 이중 103개가 다형성을 보여 다형성 비율은 94.5%였다. 6. URP5 프라이머를 이용하여 662개체를 군집 분석한 결과 밴드의 유무에 따라 16개의 그룹으로 구분하였으며, 개화기, 초장, 줄기색, 뿌리직경, 뿌리무게에 다른 분류와 일치하지 않았다.