• Title/Summary/Keyword: diversity methods

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Insights into the genetic diversity of indigenous goats and their conservation priorities

  • Liu, Gang;Zhao, Qianjun;Lu, Jian;Sun, Feizhou;Han, Xu;Zhao, Junjin;Feng, Haiyong;Wang, Kejun;Liu, Chousheng
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.10
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    • pp.1501-1510
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    • 2019
  • Objective: An experiment was conducted to evaluate genetic diversity of 26 Chinese indigenous goats by 30 microsatellite markers, and then to define conservation priorities to set up the protection programs according to the weight given to within- and between-breed genetic diversity. Methods: Twenty-six representative populations of Chinese indigenous goats, 1,351 total, were sampled from different geographic regions of China. Within-breed genetic diversity and marker polymorphism were estimated calculating the mean number of alleles, observed heterozygosities, expected heterozygosities, fixation index, effective number of alleles and allelic richness. Conservation priorities were analyzed by statistical methods. Results: A relatively high level of genetic diversity was found in twenty-four population; the exceptions were in the Daiyun and Fuqing goat populations. Within-breed kinship coefficient matrices identified seven highly inbred breeds which should be of concern. Of these, six breeds receive a negative contribution to heterozygosity when the method was based on proportional contribution to heterozygosity. Based on Weitzman or Piyasatian and Kinghorn methods, the breeds distant from others i.e. Inner Mongolia Cashmere goat, Chengdu Brown goat and Leizhou goat obtain a high ranking. Evidence from Caballero and Toro and Fabuel et al method prioritized Jining Gray goat, Liaoning Cashmere goat, and Inner Mongolia Cashmere goat, which agree with results from Kinship-based methods. Conclusion: Conservation priorities were determined according to multiple methods. Our results suggest Inner Mongolia Cashmere goat (most methods), Jining Gray goat and Liaoning Cashmere goat (high contribution to heterozygosity and total diversity) should be prioritized based on most methods. Furthermore, Daiyun goat and Shannan White goat also should be prioritized based on consideration of effective population size. However, if one breed can continually survive under changing conditions, the straightforward approach would be to increase its utilization and attraction for production via mining breed germplasm characteristics.

Bandwidth-efficient Cooperative Diversity with Rotated Constellations and Its Performance Analysis

  • Lei, Weijia;Xie, Xianzhong;Li, Xiangming
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.4 no.6
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    • pp.989-1005
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    • 2010
  • Cooperative diversity is a technique with which a virtual multiple antenna array is established among the single antenna users of the wireless network to realize space diversity. Signal space diversity (SSD) is a bandwidth-efficient diversity technique, which uses constellation rotation and interleaving techniques to achieve diversity gain. A new cooperative diversity scheme with rotated constellations (RCCD) is proposed in this paper. In this scheme, data are modulated by using a rotated constellation, and the source and the relays transmit different components of the modulated symbols. Since any one of the components contains full information of the symbols, the destination can obtain multiple signals conveying the same information from different users. In this way, space diversity is achieved. The RCCD scheme inherits the advantage of SSD - being bandwidth-efficient but without the delay problem of SSD brought by interleaving. The symbol error rate of the RCCD scheme is analyzed and simulated. The analysis and simulation results show that the RCCD scheme can achieve full diversity order of two when the inter-user channel is good enough, and, with the same bandwidth efficiency, has a better performance than amplify-and-forward and detect-and-forward methods.

Capacity of Multiuser Diversity with Cooperative Relaying in Wireless Networks (협동 릴레이와 다중 사용자 다이버시티를 이용하는 무선 통신 네트워크의 용량 분석)

  • Joung, Hee-Jin;Mun, Cheol;Seo, Jeong-Tae;Yoo, Kang-Hee
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.33 no.6C
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    • pp.423-428
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    • 2008
  • We consider the use of cooperative diversity in a multiuser wireless data network. This paper provides an analysis of the interaction between cooperative diversity and multiuser diversity on downlink channels. By using approximation of the signal-to-noise ratio (SNR) distribution of each cooperative diversity link by Gamma distribution, an analytic expression is derived for the average throughput of a single-cell wireless system with multiple cooperative diversity links combined with a fair-access scheduler. The proposed analytic approach is verified through comparisons with simulated results and shows that cooperative diversity makes the detrimental impacts on multiuser diversity.

Synthetic approach to the generation of antibody diversity

  • Shim, Hyunbo
    • BMB Reports
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    • v.48 no.9
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    • pp.489-494
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    • 2015
  • The in vitro antibody discovery technologies revolutionized the generation of target-specific antibodies that traditionally relied on the humoral response of immunized animals. An antibody library, a large collection of diverse, pre-constructed antibodies, can be rapidly screened using in vitro display technologies such as phage display. One of the keys to successful in vitro antibody discovery is the quality of the library diversity. Antibody diversity can be obtained either from natural B-cell sources or by the synthetic methods that combinatorially generate random nucleotide sequences. While the functionality of a natural antibody library depends largely upon the library size, various other factors can affect the quality of a synthetic antibody library, making the design and construction of synthetic antibody libraries complicated and challenging. In this review, we present various library designs and diversification methods for synthetic antibody library. From simple degenerate oligonucleotide synthesis to trinucleotide synthesis to physicochemically optimized library design, the synthetic approach is evolving beyond the simple emulation of natural antibodies, into a highly sophisticated method that is capable of producing high quality antibodies suitable for therapeutic, diagnostic, and other demanding applications. [BMB Reports 2015; 48(9): 489-494]

Comparison of sampling methods in biodiversity analysis of plant communities living in a riparian park area of Nakdong river (낙동강 수변공원에 서식하는 식물 군집의 종 다양성 분석 : 조사 방법에 따른 차이 비교)

  • Nam, Ki-jung;Kim, Min-jung
    • Journal of Wetlands Research
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    • v.24 no.4
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    • pp.312-319
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    • 2022
  • The species diversity of plant communities is quantitatively measured, and can be affected by plant monitoring methods. This study experimentally compared the structure and diversity of plant communities living in five waterfront park areas in Nak-dong River using three plant survey methods (modified Whittaker, modified Daubenmire, and modified point-line intercept method). According to the diversity profile, the modified Whittaker method produced the highest species richness regardless of the location, but which method makes the highest diversity of dominant species varies depending on the location. The Beta diversity of the communites calculated from the modified Whittaker and the modified Daubenmire suggested that structures of plant communities in five locations were similar, while the Point-line interception method suggested that a small number of dominant species were shared between communities.

Broadcast Packet Data Transmission for OFDM-based Mobile Cellular Networks (OFDM 기반 이동 셀룰러 망에서의 브로드캐스트 패킷 데이터 전송)

  • Kang Sung-Kyo;Kim Yun-Hee;Kwon Jae-Kyun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6A
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    • pp.556-562
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    • 2006
  • In this paper, macro diversity coding methods are proposed to efficiently transmit broadcast packet data over mobile cellular networks based on OFDM. In the method, cells are divided into multiple cell groups which transmit one of two orthogonal branches in a transmit diversity code. Furthermore, a coded packet is partitioned into the subblocks for which different cell group combinations are assigned to transmit two different branches. The methods extend the cell coverage at the same transmit power due to the transmit diversity of each symbol and coding diversity obtained through different fading statistics over the subblocks.

Penicillium Diversity from Intertidal Zone in Korea

  • Park, Myung Soo;Lee, Seobihn;Oh, Seung-Yoon;Lim, Young Woon
    • 한국균학회소식:학술대회논문집
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    • 2016.05a
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    • pp.11-11
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    • 2016
  • Penicillium species are commonly isolated from various outdoor and indoor environments, including marine environments such as sponges, algae and sand. Penicillium is especially important because numerous bioactive compounds have been isolated. Penicillium was the most common species in intertidal zone in Korea, however the diversity and ecological roles of Penicillium in intertidal zone are not clarified. We explored diversity and ecological roles of marine-derived Penicillium from tidal flat and sea sand in Korea. The diversity of marine-derived Penicillium from Korea was investigated using both culture-dependent and culture-independent approach by ${\beta}$-tubulin sequence. In addition, we evaluated optimal temperature, halo-tolerance, and enzyme activity of Penicillium strains, such as extracellular alginase, endoglucanase, ${\beta}$-glucosidase, and protease. For culture-dependent approach, a total of 182 strains of 62 Penicillium species were isolated, with 53 species being identified. The most common species was Penicillium oxalicum, followed by P. crustosum, P. brasilianum, P. koreense, and P. griseofulvum. Species richness and composition were not significantly different by season, substrates, and seaside. For culture-independent approach using Illumina sequencing, 73 OTUSs were detected. The most frequently observed species was P. antarcticum, followed by P. koreense, P. crustosum, and P. brevicompactum. Diversity of Penicillium was higher during winter season than during summer season and in western sea than in southern sea, respectively. Community structure was significantly different by season and sea side. 52 species were detected by both methods. Unique species were isolated from each of methods - 10 from culture methods and 21 from Illumina sequencing. Furthermore, salinity adaption of the Penicillium varied depending on species. Many Penicillium species showed endoglucanase, ${\beta}$-glucosidase, and protease activity. Some species including P. paneum and P. javanicum degraded the polycyclic aromatic hydrocarbons. Thus, our results demonstrate that intertidal zone in Korea harbors diverse Penicillium community and marine-derived Penicillium play important ecological roles as decomposers of organic material in marine environments.

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Fungal Load of Groundwater Systems in Geographically Segregated Islands: A Step Forward in Fungal Control

  • Joong Hee Cho;Nam Soo Jun;Jong Myong Park;Ki In Bang;Ji Won Hong
    • Mycobiology
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    • v.50 no.5
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    • pp.345-356
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    • 2022
  • The fungal distribution, diversity, and load were analyzed in the geographically segregated island groundwater systems in Korea. A total of 79 fungal isolates were secured from seven islands and identified based on the internal transcribed spacer (ITS) sequences. They belonged to three phyla (Ascomycota, Basidiomycota, and Chlorophyta), five classes, sixteen orders, twenty-two families, and thirty-one genera. The dominant phylum was Ascomycota (91.1%), with most fungi belonging to the Cladosporium (21.5%), Aspergillus (15.2%), and Stachybotrys (8.9%) genera. Cladosporium showed higher dominance and diversity, being widely distributed throughout the geographically segregated groundwater systems. Based on the diversity indices, the genera richness (4.821) and diversity (2.550) were the highest in the groundwater system of the largest scale. As turbidity (0.064-0.462) increased, the overall fungal count increased and the residual chlorine (0.089-0.308) had low relevance compared with the total count and fungal diversity. Cladosporium showed normal mycelial growth in de-chlorinated sterilized samples. Overall, if turbidity increases under higher fungal diversity, bio-deterioration in groundwater-supplying facilities and public health problems could be intensified, regardless of chlorine treatment. In addition to fungal indicators and analyzing methods, physical hydrostatic treatment is necessary for monitoring and controlling fungal contamination.

Deciphering Diversity Indices for a Better Understanding of Microbial Communities

  • Kim, Bo-Ra;Shin, Jiwon;Guevarra, Robin B.;Lee, Jun Hyung;Kim, Doo Wan;Seol, Kuk-Hwan;Lee, Ju-Hoon;Kim, Hyeun Bum;Isaacson, Richard E.
    • Journal of Microbiology and Biotechnology
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    • v.27 no.12
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    • pp.2089-2093
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    • 2017
  • The past decades have been a golden era during which great tasks were accomplished in the field of microbiology, including food microbiology. In the past, culture-dependent methods have been the primary choice to investigate bacterial diversity. However, using culturein-dependent high-throughput sequencing of 16S rRNA genes has greatly facilitated studies exploring the microbial compositions and dynamics associated with health and diseases. These culture-independent DNA-based studies generate large-scale data sets that describe the microbial composition of a certain niche. Consequently, understanding microbial diversity becomes of greater importance when investigating the composition, function, and dynamics of the microbiota associated with health and diseases. Even though there is no general agreement on which diversity index is the best to use, diversity indices have been used to compare the diversity among samples and between treatments with controls. Tools such as the Shannon-Weaver index and Simpson index can be used to describe population diversity in samples. The purpose of this review is to explain the principles of diversity indices, such as Shannon-Weaver and Simpson, to aid general microbiologists in better understanding bacterial communities. In this review, important questions concerning microbial diversity are addressed. Information from this review should facilitate evidence-based strategies to explore microbial communities.

Integrated Education for Sustainable Character, Human Rights, Cultural Diversity Based on Family Life Education: Focusing on University Students (가정생활교육에 기반한 지속가능한 인성, 인권, 문화다양성 통합교육: 대학생을 중심으로)

  • Kim, WooJoung;Ju, YoungAe
    • Human Ecology Research
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    • v.58 no.1
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    • pp.31-41
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    • 2020
  • This study examined human rights perception, cultural diversity perception, level of character perception, and influencing factors for university students in order to prepare basic data on integrated education methods of character, human rights and cultural diversity and education program models. The research questions are as follows. 1. What are university students' perceptions of character, cultural diversity and human rights? 2. What is the status of the experience of family life education on character, cultural diversity, and human rights, and is it related to the level of perception? 3. What variables affect character perception, cultural diversity perception, and human rights perception? The survey targeted 407 students at two universities in Seoul and used IBM PASW Statistics as a tool to analyze data. The study results are as follows. First, university students' character, cultural diversity and human rights perception were above average; however, empirical education is still required because they had low scores in the area of action. Second, male university students have less experience in family life education on character, cultural diversity and human rights compared to female university students. Third, it is necessary to integrate education for character, cultural diversity and human rights because the most influential factors in character perception, cultural diversity perception and human rights perception were character education. The role of family life education should be considered important because personality education in the home showed a relatively high correlation.