• Title/Summary/Keyword: Research Diversity

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Comparison of Fecal Microbiota between Birth and Weaning of Halla Horses Using 16S rRNA Gene Amplicon Sequencing (16S 앰플리콘 시퀀싱 기반 한라마 출생시와 이유기의 분변 미생물 비교 분석)

  • Lee, Jongan;Kang, Young-Jun;Choi, Jae-Young;Shin, Sang-Min;Shin, Moon-Cheol
    • Journal of Life Science
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    • v.32 no.12
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    • pp.1005-1012
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    • 2022
  • This study was conducted to investigate the taxonomic composition and diversity of fecal microbiota between birth and weaning stages of Halla horses using 16S rRNA gene amplicon sequencing analysis. Proteobacteria (35.7%) and Firmicutes (45.6%) were identified as the most common phylum in birth and weaning, respectively. Escherichia (19.7%) and Clostridium (14.0%) were observed as the most dominant genus in birth, and Fibrobacter (6.6%) was the highest in weaning. The results of α-diversity showed that the richness and evenness in microbial communities were statistically significant (p<0.001) in birth and weaning. The results of β-diversity indicated that the birth and weaning stages were clearly divided into two groups at the genus and species levels. Permutational multivariate analysis of variance (PERMANOVA) showed that the microbiota composition differences between birth and weaning were statistically significant (q<0.001). A linear discriminant analysis effect (LEfSe) was performed to select taxonomic makers between the birth and weaning stages. On the genus level, Escherichia, Bacteroides, Clostridium, and Methylobacterium were relatively abundant at birth, whereas Fibrobacter was more abundant at weaning. We expect that this research can be utilized as basic data in the identification of microbial communities involved in disease prevention and nutrient absorption in Halla horses.

Lipase Diversity in Glacier Soil Based on Analysis of Metagenomic DNA Fragments and Cell Culture

  • Zhang, Yuhong;Shi, Pengjun;Liu, Wanli;Meng, Kun;Bai, Yingguo;Wang, Guozeng;Zhan, Zhichun;Yao, Bin
    • Journal of Microbiology and Biotechnology
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    • v.19 no.9
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    • pp.888-897
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    • 2009
  • Lipase diversity in glacier soil was assessed by culture-independent metagenomic DNA fragment screening and confirmed by cell culture experiments. A set of degenerate PCR primers specific for lipases of the hormone-sensitive lipase family was designed based on conserved motifs and used to directly PCR amplify metagenomic DNA from glacier soil. These products were used to construct a lipase fragment clone library. Among the 300 clones sequenced for the analysis, 201 clones encoding partiallipases shared 51-82% identity to known lipases in GenBank. Based on a phylogenetic analysis, five divergent clusters were established, one of which may represent a previously unidentified lipase subfamily. In the culture study, 11 lipase-producing bacteria were selectively isolated and characterized by 16S rDNA sequences. Using the above-mentioned degenerate primers, seven lipase gene fragments were cloned, but not all of them could be accounted for by the clones in the library. Two full-length lipase genes obtained by TAIL-PCR were expressed in Pichia pastoris and characterized. Both were authentic lipases with optimum temperatures of ${\le}40^{\circ}C$. Our study indicates the abundant lipase diversity in glacier soil as well as the feasibility of sequence-based screening in discovering new lipase genes from complex environmental samples.

Evaluation of selection program by assessing the genetic diversity and inbreeding effects on Nellore sheep growth through pedigree analysis

  • Illa, Satish Kumar;Gollamoori, Gangaraju;Nath, Sapna
    • Asian-Australasian Journal of Animal Sciences
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    • v.33 no.9
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    • pp.1369-1377
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    • 2020
  • Objective: The main objectives of the present study were to assess the genetic diversity, population structure and to appraise the efficiency of ongoing selective breeding program in the closed nucleus herd of Nellore sheep through pedigree analysis. Methods: Information utilized in the study was collected from the pedigree records of Livestock Research Station, Palamaner during the period from 1989 to 2016. Genealogical parameters like generation interval, pedigree completeness, inbreeding level, average relatedness among the animals and genetic conservation index were estimated based on gene origin probabilities. Lambs born during 2012 and 2016 were considered as reference population. Two animal models either with the use of Fi or ΔFi as linear co-variables were evaluated to know the effects of inbreeding on the growth traits of Nellore sheep. Results: Average generation interval and realized effective population size for the reference cohort were estimated as 3.38±0.10 and 91.56±1.58, respectively and the average inbreeding coefficient for reference population was 3.32%. Similarly, the effective number of founders, ancestors and founder genome equivalent of the reference population were observed as 47, 37, and 22.48, respectively. Fifty per cent of the genetic variability was explained by 14 influential ancestors in the reference cohort. The ratio fe/fa obtained in the study was 1.21, which is an indicator of bottlenecks in the population. The number of equivalent generations obtained in the study was 4.23 and this estimate suggested the fair depth of the pedigree. Conclusion: Study suggested that the population had decent levels of genetic diversity and a non-significant influence of inbreeding coefficient on growth traits of Nellore lambs. However, small portion of genetic diversity was lost due to a disproportionate contribution of founders and bottlenecks. Hence, breeding strategies which improve the genetic gain, widens the selection process and with optimum levels of inbreeding are recommended for the herd.

Fermentation Characteristics and Microbial Diversity of Tropical Grass-legumes Silages

  • Ridwan, Roni;Rusmana, Iman;Widyastuti, Yantyati;Wiryawan, Komang G.;Prasetya, Bambang;Sakamoto, Mitsuo;Ohkuma, Moriya
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.4
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    • pp.511-518
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    • 2015
  • Calliandra calothyrsus preserved in silage is an alternative method for improving the crude protein content of feeds for sustainable ruminant production. The aim of this research was to evaluate the quality of silage which contained different levels of C. calothyrsus by examining the fermentation characteristics and microbial diversity. Silage was made in a completely randomized design consisting of five treatments with three replications i.e.: R0, Pennisetum purpureum 100%; R1, P. purpureum 75%+C. calothyrsus 25%;, R2, P. purpureum 50%+C. calothyrsus 50%; R3, P. purpureum 25%+C. calothyrsus 75%; and R4, C. calothyrsus 100%. All silages were prepared using plastic jar silos (600 g) and incubated at room temperature for 30 days. Silages were analyzed for fermentation characteristics and microbial diversity. Increased levels of C. calothyrsus in silage had a significant effect (p<0.01) on the fermentation characteristics. The microbial diversity index decreased and activity was inhibited with increasing levels of C. calothyrsus. The microbial community indicated that there was a population of Lactobacillus plantarum, L. casei, L. brevis, Lactococcus lactis, Chryseobacterium sp., and uncultured bacteria. The result confirmed that silage with a combination of grass and C. calothyrsus had good fermentation characteristics and microbial communities were dominated by L. plantarum.

Changing Methodologies and Reshaping Concepts in Biodiversity Science: A Historical Review of Research on Human Genetic Diversity (생물학 연구 방법론 변화에 따른 생물다양성 개념의 전환: 인간 유전다양성 연구 사례)

  • Hyun, Jaehwan
    • Korean Journal of Environmental Biology
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    • v.32 no.4
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    • pp.413-425
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    • 2014
  • In order to shed some light on the historical change of biodiversity concepts, this paper reviews the science and technology studies (STS) literature on the history of biological research on human genetic diversity. By doing that, I show how the notion of genetic diversity in the human population - from "race" to "population" to "biogeographical ancestry" - has changed with methodologies and techniques over the last hundred years. In the meantime, I point out contexts and situations, despite conceptual and methodological developments, that show that current human genetic diversity research is slipping into the past mistakes of scientific racism. This article offers biodiversity researchers an opportunity to consider their own scientific practices on classifying species more reflectively.

SMEs' External Technology Collaboration Network Diversity and Productivity Improvement : The Moderating Effect of the Chief Technology Officer-Driven Technology Development (중소기업의 외부 기술협력 네트워크의 다양성과 생산성 향상 : 최고기술경영자가 주도하는 기술 개발의 조절효과)

  • Hau, Yong Sauk
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.40 no.2
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    • pp.99-103
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    • 2017
  • Productivity improvement is one of the important goals which firms' technology developments aim at. Firms' improved productivity from technology development means that their inputs can produce more outputs through technology development, which makes firms' productivity improvement from technology development more and more important in the age of technology advance and convergence like today. This research empirically analyzes the influence of the external technology collaboration network diversity on the productivity improvement of the small and medium-sized enterprises (SMEs) from technology development and the moderating effect of the chief technology officer (CTO)-driven technology development on this influence. This study constructs the research model reflecting the moderating impact of the CTO-driven technology development and tests it with the ordinary least squares regression through the IBM SPSS version 23 by using the 2,000 data about South Korean SMEs. This research empirically reveals two points. One is that SMEs' external technology collaboration network diversity has a positive influence on their productivity improvement from technology development. The other is that the positive effect of SMEs' external technology collaboration network diversity on their productivity improvement from technology development is moderated by the CTO-driven technology development. The two points revealed in this study present two meaningful implications in not only the practical but also academic point of view. The practical implication is that it is effective for SMEs to use CTOs in increasing their productivity improvement from technology development. The academic implication is that making technology collaboration with more diverse external partners can increase SMEs' productivity improvement from technology development.

The Role of justice and organizational citizenship behaviour in the relation between measurement diversity and managerial performance (성과지표의 다양성과 관리적 성과 간의 관계에서 공정성과 조직시민행동의 역할)

  • Lee, Sang-Wan;Cho, Yong-Eon;Lee, Kyu-Sub
    • Journal of Digital Convergence
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    • v.11 no.11
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    • pp.219-231
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    • 2013
  • Many companies are adopting performance measurement systems(PMS) in order to acquire competitive advantage the promote long-term growth in Coping with the rapidly changing business environment. Prior research has focused on the relation between PMS and organizational performance. However, there is limited empirical research that examines the behavioural consequences of PMS. Further, there is little empirical research that examines whether measurement diversity have direct and/or indirect effects on work performance. As such, I examine how the relation between measurement diversity and managerial performance can be explained by the intervening variables of justice and organizational citizenship behaviour. This study is summarized as follows: this study finds that measurement diversity affect managerial performance indirectly through justice and organizational citizenship behaviour.

Phylogenetic Analysis of Culturable Arctic Bacteria

  • Lee Yoo Kyung;Kim Hyo Won;Kang Sung-Ho;Lee Hong Kum
    • Proceedings of the Microbiological Society of Korea Conference
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    • 2003.05a
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    • pp.26-33
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    • 2003
  • We isolated and identifed culturable Arctic bacteria that have inhabited around Korean Arctic Research Station Dasan located at Ny-Alsund, Svalbard, Norway $(79^{\circ}N,\;12^{\circ}E)$. The pure colonies were inoculated into nutrient liquid media, genomic DNA was extracted, and phylogenetic analysis was performed on the basis of 16S rDNA sequences. Out of total 227 strains, 198 strains were overlapped or unidentified, and 43 bacteria were finally identified: 31 strains belonged to Pseudomonas, 7 strains Arthrobacter, two Flavobacterium sp., an Achromobacter sp., a Pedobacter sp., and a Psychrobacter sp. For isolation of diverse bacteria, we need more effective transport method than 3M petri-films, which were used for convenience of transportation that was restricted by volume. We also need to use other culture media than nutrient media. We expect these Arctic bacteria can be used for screening to develop new antibiotics or industrial enzymes that are active at low temperature.

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The Role of Intellectual Property Rights for Conserving Biological Diversity - Patent Law Treaty for Protecting Genetic Resources and Traditional Knowledge - (생물다양성보전을 위한 지적재산권의 역할 연구 - 유전자원과 전통지식 보호를 위한 특허법의 역할 중심으로 -)

  • Kang, Gil-Mo;Yeom, Jae-Ho;Doh, Seong-Jae;Lee, C. Mi-Jin;Kwon, Suk-Jae
    • Ocean and Polar Research
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    • v.29 no.1
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    • pp.43-53
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    • 2007
  • Recently, controversy over intellectual property rights for protecting genetic resources and traditional knowledge has been emerging. Very active debates and global discussions are being carried out in various international organizations for possible approaches to be taken for these properties, and for the fair and equal sharing of the benefits from these intellectual properties. There is a need to evaluate adopting a sui generis system which is being pushed by developing nations, or adopting a policy which will guaranteee benefit sharing such as sharing royalties from marketing final products, technical transfers, capacity building, and participating in research activities. Also, it is very important to examine the legal issues concerning genetic resources based on Convention on Biological Diversity for the fair and equal sharing of the benefits with developing nations, at the same time assuring developed nations of access to genetic resources.

Population genetic structure based on mitochondrial DNA analysis of Ikonnikov's whiskered bat (Myotis ikonnikovi-Chiroptera: Vespertilionidae) from Korea

  • Park, Soyeon;Noh, Pureum;Choi, Yu-Seong;Joo, Sungbae;Jeong, Gilsang;Kim, Sun-Sook
    • Journal of Ecology and Environment
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    • v.43 no.4
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    • pp.454-461
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    • 2019
  • Background: Ikonnikov's whiskered bat (Myotis ikonnikovi) is found throughout the Korean Peninsula, as well as in Kazakhstan, Russia, Mongolia, China, and Japan. It is small-sized and primarily inhabits old-growth forests. The decrease and fragmentation of habitats due to increased human activity may influence the genetic structure of bat populations. This study was designed to elucidate the population genetic structure of M. ikonnikovi using mitochondrial genes (cytochrome oxidase I and cytochrome b). Results: The results showed that M. ikonnikovi populations from Korea have high genetic diversity. Although genetic differentiation was not detected for the COI gene, strong genetic differentiation of the Cytb gene between Mt. Jeombong and Mt. Jiri populations was observed. Moreover, the results indicated that the gene flow of the maternal lineage may be limited. Conclusions: This study is the first to identify the genetic population structure of M. ikonnikovi. We suggest that conservation of local populations is important for sustaining the genetic diversity of the bat, and comprehensive studies on factors causing habitat fragmentation are required.