• BMB Reports
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• 제49권12호
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• pp.662-670
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• 2016

The human oral cavity contains a highly personalized microbiome essential to maintaining health, but capable of causing oral and systemic diseases. Thus, an in-depth definition of "healthy oral microbiome" is critical to understanding variations in disease states from preclinical conditions, and disease onset through progressive states of disease. With rapid advances in DNA sequencing and analytical technologies, population-based studies have documented the range and diversity of both taxonomic compositions and functional potentials observed in the oral microbiome in healthy individuals. Besides factors specific to the host, such as age and race/ethnicity, environmental factors also appear to contribute to the variability of the healthy oral microbiome. Here, we review bioinformatic techniques for metagenomic datasets, including their strengths and limitations. In addition, we summarize the interpersonal and intrapersonal diversity of the oral microbiome, taking into consideration the recent large-scale and longitudinal studies, including the Human Microbiome Project.

• 아동학회지
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• 제13권2호
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• pp.229-240
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• 1992

Although play is a key element in child development, little research has been done on how play is conceptualized by adults directly involved with children on a daily basis. The purpose of the study was to determine meanings of the concept "play" held by mothers of preschool children in Korea. Specifically, the study sought to determine Korean mothers' conceptions of the nature and functions of play, and their conceptions of play in contrast to work. An open-ended/semi-structured interview instrument was constructed to generate research data. Interview questions focused on three content categories: (1) the nature of play, (2) the functions of play, and (3) conceptions of work. Questions in each content category consisted of four distinct types: (1) experience/behavioral, (2) opinion/value, (3) feeling, and (4) knowledge. The instrument was pilot-tested with two subjects, revised, and administered to eleven mothers of preschool children. Interview data were subjected to domain and taxonomic analyses. Analyses yielded two principal themes: (1) Play is viewed as an intrinsically motivated and pleasurable activity; (2) while play and work could be consonant, the values inherent in play and work are generally in opposition.

• ALGAE
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• 제21권4호
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• pp.349-375
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• 2006

The application of modern ecological, ultrastructural and molecular methods, aided by the cultivation of numerous cyanobacterial morphotypes, has substantially changed our knowledge of these organisms. It has led to major advances in cyanobacterial taxonomy and criteria for their phylogenetic classification. Molecular data provide basic criteria for cyanobacterial taxonomy; however, a correct phylogenetic system cannot be constructed without combining genetic data with knowledge from the previous 150 years research of cyanobacterial diversity. Thus, studies of morphological variation in nature, and modern morphological, ultrastructural, ecophysiological and biochemical characters need to be combined in a “polyphasic” approach. Taxonomic concepts for generic and infrageneric ranks are re-evaluated in light of combined phenotypic and molecular criteria. Despite their usefulness in experimental studies, the limitations of using strains from culture collections for systematic and nomenclatural purposes is highlighted. The need for a continual revision of strain identification and proper nomenclatural practice associated with either the bacteriological or botanical codes is emphasized. Recent advances in taxonomy are highlighted in the context of prospects for understanding cyanobacterial diversity from natural habitats, and the evolutionary and adaptational processes that cyanobacteria undergo.

• 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)

• Environmental Engineering Research
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• 제19권4호
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• pp.317-329
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• 2014

The diversity of cyanobacteria in Sri Lanka was studied in different water reservoirs, paddy fields, brackish water and tsunami affected areas using light microcopy, 16S rRNA sequences, followed by phylogenetic analysis. Based on light microscopy, 24 genera were identified from environmental samples belonging to the orders Chroococcales, Oscillatoriales, Pleurocapsales and Nostocales. In cultures, 33 genera were identified from all five cyanobacterial orders, including Stigonematales. Based on 16S rRNA gene sequences and their morphology, two isolates were identified up to species level, 72 to genus level, one isolate up to family and 11 up to order level. Twelve isolates couldn't be assigned to any taxonomic level. The results of 16S rRNA gene sequences along with the phylogenetic analysis indicated that some cyanobacterial isolates could be accommodated to genus or order level. The 16S rRNA sequence analysis data in this study confirmed that order Nostocales and order Pleurocapsales cyanobacteria are monophyletic while orders Chroococcales, Oscillatoriales and Stigonematales cyanobacteria are polyphyletic. Polyphasic approach including the combination of light microscopy, cultures and the analysis of 16S rRNA gene sequences provide a promising approach to ascertain the diversity of cyanobacteria in different habitats.

• International Journal of Industrial Entomology and Biomaterials
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• 제2권1호
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• pp.37-53
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• 2001

Two regions of mtDNA genome, cytochrome oxidase subunit I (COI) and 165 ribosomal RNA (165 rRNA) genes, were sequenced for 15 species of the long-horned beetle belonging to four subfamilies and geographic samples of mulberry longicorn beetle, Apriona germari, from two localities in Korea. Ten samples of A. germari collected from Suwon and Busan revealed three COI haplotypes ranging in nucleotide divergence of 0.3% to 0.5%, and the two populations shared one common COI haplotype (80%). The sequence divergence among 15 species of the long-horned beetle was much higher in COI gene (12.3%∼39.4%) than 16S rRNA gene (7.2% to 23.1), and the maximum value in the COI gene is exceptional compared with other relevant studies, including that of Coleoptera. The greatly increased divergence in the COI gene, in facto was stemmed from a peculiar sequence of Prionus insularis belonging to Prioninne, divergence of which ranges from 31.2% to 39.3% from other species. We discussed possible reason of the divergence in this species. Due to the abnormality of COI gene divergence, decrease in phylogenetic signal was severe in COI nucleotide and, subsequently, the converted amino acid sequences, rendering us to put more confidence on the 16S5 rRNA gene data. Although the molecular phylogeny confidently supports the monophyletic origin of Lepturinae, the presence of discrepancy between molecular data and traditional taxonomic views also is a testable hyothesis. One such discrepancy includes taxonomic position of Sophronica obrioides and Theophilea cylindricollis belonging to Lamiinae.

• Animal Systematics, Evolution and Diversity
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• 제3권2호
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• pp.64-116
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• 1987

본 연구는 우리나라의 식물, 특히 야생 식물에 기생하는 응애과에 대한 분류 학적 검토를 위하여 이루어졌다. 주로 호남지방에서 1986년 5월부터 1987년 6월 사이에 다음과 같은 12종(*한국미기록종)의 응애가 채집되어 관찰과 실험에 사용되었다. 1. Panonyehus citri (McGregor) 귤응애 *2. Eotetranyehus populi Koch 버들응애 (신칭) * 3. E. Smithi Pritchard and Baker 스미드응애(신칭) *4. Schizotetranyehus bambusae Reck 대응애 (신청) *5. S. celarius (Banks) 납작대응애 (신칭) *6. S. leguminosus Ehara 싸리응애 (신청) *7. Oligonychus orthius Rimando 억새응애(신칭) 8. Tetranyehus kanzawai Kishida 차응애 *9. T. phaselus Ehara 콩응애(신청) *10. T. truneatus Ehara 뽕나무응애(신청) 11. T. vienensis Zacher 벚나무응애 12. T. urtieae Koch 점박이응애. 이와 아울러 전부절의 조간체에 대한 미세구조를 관찰, 비교하였고, 전기영 동법에 의한 효소분석을 실시하여 비교함으로써 종 및 속간의 상호유연관계를 추찰하여 보았다.

• 한국어류학회지
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• 제11권2호
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• pp.198-210
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• 1999

한국산 홍어과(科) 어류(魚類)에 대한 분류학적(分類學的) 고찰(考察)과 국명(國名) 및 분포(分布) 범위(範圍)를 정리(整理)하기 위해 국내외의 표본(標本)과 문헌(文獻)을 통하여 재검토(再檢討)하였다. 그 결과 홍어과 어류는 4속(屬) 11종(種), 즉 Bathyraja bergi 바닥가오리, B. isotrachys 저자가오리, Dipturus kwangtungensis 광동홍어, D. macrocauda 도랑가오리, D. tengu 살홍어, Okamejei acutispina 무늬홍어, O. boesemani 깨알홍어, O. kenojei 홍어, O. meerdervoortii 오동가오리, Raja koreana 고려홍어 및 R. pulchra "참홍어" (국명개정(國名改稱)) 등으로 확인되었다. Dipturus속(屬)과 Okamejei속(屬)은 아속(亞屬)에서 속(屬)으로 승격되었기 때문에 각각 "살홍어속(屬)"과 "홍어속(屬)"으로 국명개정(國名新稱)하였고, Raja속(屬)은 "참홍어속(屬)"으로 국명개정(國名新稱)하였다. 분류학적 재검토의 결과 Bathyraja bergi 바닥가오리도 분포함을 알 수 있었다. 한국산 홍어과 어류의 종(種) 목록(目錄)과 분포도(分布圖)를 제시하였다.

• Parasites, Hosts and Diseases
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• 제55권3호
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• pp.287-294
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• 2017

The present study was performed to record new definitive hosts of Isthmiophora hortensis, and to describe morphological characteristics derived from a variety of worm samples for clarification of its taxonomic validity. Morphological characteristics with dimensions were observed in worm samples (n=21) from naturally infected wild animals, including a raccoon dog Nyctereutes procyonoides from Gimhae-si (City), Gyeongsangnam-do, stray cats and a striped field mouse from several localities, and a wild boar Sus scrofa, from Gurye-gun (County), Jeollanam-do. In addition, adult flukes (n=45) recovered in albino rats experimentally infected with the metacercariae from a freshwater fish species were also subjected to morphological studies. The mean ratios of the body length (BL) to body width (BW) were 5.86 and 5.76 in worms from wild animals and experimental rats, respectively. Those of the ventral sucker to oral sucker were 2.92 and 3.01 in worms from 2 groups. The mean percentages of the hindbody length (HBL) to BL were 42.1 and 41.2 in 2 groups. Those of uterine fields to BL were 9.8 and 12.2 in the 2 worm groups. By the present study, the 2 species of wild animals, the raccoon dog and wild boar, have been added as new definitive hosts for I. hortensis. The morphological characteristics of adult flukes derived from a variety of host source were redescribed to support the taxonomic validity of this echinostome species.

• 천문학회보
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• 제43권1호
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• pp.42.1-42.1
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• 2018

Deep Ecliptic Patrol of the Southern Sky (DEEP-South) observation is being made during the off-season for exoplanet survey, using Korea Microlensing Telescope Network (KMTNet). An optimal combination of its prime focus optics and the 0.3 billion pixel CCD provides a four square degrees field of view with 0.4 arcsec/pixel plate scale which is also best suited for small body studies. Normal operation of KMTNet started in October 2015, and a significant portion of the allocated telescope time for DEEP-South is dedicated to targeted observation, Opposition Census (OC), of near-Earth asteroids for physical and taxonomic characterization. This is effectively achieved through multiband, time series photometry using Johnson-Cousins BVRI filters. Uninterrupted monitoring of the southern sky with KMTNet is optimized for spin characterization of a broad spectrum of asteroids ranging from the near-Earth space to the main-belt, including binaries, asteroids with satellites, slow/fast- and non-principal axis-rotators, and thus is expected to facilitate the debiasing of previously reported lightcurve observations. Our software subsystem consists of an automated observation scheduler, a pipelined data processing system for differential photometry, and an easy-to-use lightcurve analysis toolkit. Lightcurves, spin periods and provisional determination of class of asteroids to which the lightcurve belongs will be presented, using the dataset from first year operation of KMTNet. Our new taxonomic classification scheme for asteroids will also be summarized.