• 대한수의학회지
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• 제51권2호
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• pp.107-115
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• 2011

Theileria (T.) buffeli (formerly T. sergenti/T. orientalis) is the major hemo-protozoan distributed in the Far East Asian countries such as Korea, China and Japan. It is responsible for the clinical symptoms of anorexia, ateliosis, anemia, fever and icterus. It also causes abortion and sudden death under severe cases, resulting in economic losses for many livestock farms. The objective of this study was to analyze the genetic diversity of the major surface protein (Msp) gene in T. buffeli in Holstein in Korea, and we characterized the association of the diversification of the Msp gene and its relationship with the pathogenicity of Theileria. For this, complete blood counts and Theileria PCR sequence analysis were performed from 57 Holstein in Jeju Island. A total of 26 PCR positive Holstein (16 anemic and 10 non-anemic) were then randomly selected based on 18s rRNA sequence typing of the Theileria Msp gene. The DNA sequence of the T. buffeli Msp gene in Holstein showed 99.0%, 99.2%, 99.9%, 99.5%, 98.7%, 98.4% and 98.4% homology with T. sergenti, Theileria spp., T. sergenti, Theileria spp., Theileria spp., Theileria spp. and Theileria spp., respectively. The result showed a genetic variation of 57.7% (type I), 3.8% (type II), 15.4% (type III), 7.7% (type IV), 13.5% (type V) and 1.9% (type VI). Type I is the most frequent type in both anemic and non-anemic Holstein while type II was found in only non-anemic Holstein. This results of our study help confirm the diversity of Msp gene types and demonstrate that the gene type distribution of Msp genes varies among Theileria-infected Holstein in Jeju Island.

• 전자공학회논문지A
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• 제31A권2호
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• pp.1-8
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• 1994

In this paper, a model of trellis-coded M-ary PSK (TCM/M-PSK) for digital land mobile communication is realized. Bit error rate(BER) of TCM/M-PSK is calculated theoretically in time selective fading environment due to Doppler spread in the presence of AWGN. cochannel interference. These analyses are employed the receiver with post detection diversity and the direct sequence to improve the BER performance of TCM-MPSK system. It is shown that the CNR required by the diversity reception and the direct sequece(process gain=20dB) TCM-4PSK system is reduced to about 25 dB.

• Parasites, Hosts and Diseases
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• 제55권4호
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• pp.367-374
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• 2017

Despite the broad distribution of leishmaniasis among Iranians and animals across the country, little is known about the genetic characteristics of the causative agents. Applying both HSP70 PCR-RFLP and sequence analyses, this study aimed to evaluate the genetic diversity and phylogenetic relationships among Leishmania spp. isolated from Iranian endemic foci and available reference strains. A total of 36 Leishmania isolates from almost all districts across the country were genetically analyzed for the HSP70 gene using both PCR-RFLP and sequence analysis. The original HSP70 gene sequences were aligned along with homologous Leishmania sequences retrieved from NCBI, and subjected to the phylogenetic analysis. Basic parameters of genetic diversity were also estimated. The HSP70 PCR-RFLP presented 3 different electrophoretic patterns, with no further intraspecific variation, corresponding to 3 Leishmania species available in the country, L. tropica, L. major, and L. infantum. Phylogenetic analyses presented 5 major clades, corresponding to 5 species complexes. Iranian lineages, including L. major, L. tropica, and L. infantum, were distributed among 3 complexes L. major, L. tropica, and L. donovani. However, within the L. major and L. donovani species complexes, the HSP70 phylogeny was not able to distinguish clearly between the L. major and L. turanica isolates, and between the L. infantum, L. donovani, and L. chagasi isolates, respectively. Our results indicated that both HSP70 PCR-RFLP and sequence analyses are medically applicable tools for identification of Leishmania species in Iranian patients. However, the reduced genetic diversity of the target gene makes it inevitable that its phylogeny only resolves the major groups, namely, the species complexes.

• Asian-Australasian Journal of Animal Sciences
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• 제14권6호
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• pp.880-884
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• 2001

Rumen microbiology research has undergone several evolutionary steps: the isolation and nutritional characterization of readily cultivated microbes; followed by the cloning and sequence analysis of individual genes relevant to key digestive processes; through to the use of small subunit ribosomal RNA (SSU rRNA) sequences for a cultivation-independent examination of microbial diversity. Our knowledge of rumen microbiology has expanded as a result, but the translation of this information into productive alterations of ruminal function has been rather limited. For instance, the cloning and characterization of cellulase genes in Escherichia coli has yielded some valuable information about this complex enzyme system in ruminal bacteria. SSU rRNA analyses have also confirmed that a considerable amount of the microbial diversity in the rumen is not represented in existing culture collections. However, we still have little idea of whether the key, and potentially rate-limiting, gene products and (or) microbial interactions have been identified. Technologies allowing high throughput nucleotide and protein sequence analysis have led to the emergence of two new fields of investigation, genomics and proteomics. Both disciplines can be further subdivided into functional and comparative lines of investigation. The massive accumulation of microbial DNA and protein sequence data, including complete genome sequences, is revolutionizing the way we examine microbial physiology and diversity. We describe here some examples of our use of genomics- and proteomics-based methods, to analyze the cellulase system of Ruminococcus flavefaciens FD-1 and explore the genome of Ruminococcus albus 8. At Illinois, we are using bacterial artificial chromosome (BAC) vectors to create libraries containing large (>75 kbases), contiguous segments of DNA from R. flavefaciens FD-1. Considering that every bacterium is not a candidate for whole genome sequencing, BAC libraries offer an attractive, alternative method to perform physical and functional analyses of a bacterium's genome. Our first plan is to use these BAC clones to determine whether or not cellulases and accessory genes in R. flavefaciens exist in clusters of orthologous genes (COGs). Proteomics is also being used to complement the BAC library/DNA sequencing approach. Proteins differentially expressed in response to carbon source are being identified by 2-D SDS-PAGE, followed by in-gel-digests and peptide mass mapping by MALDI-TOF Mass Spectrometry, as well as peptide sequencing by Edman degradation. At Ohio State, we have used a combination of functional proteomics, mutational analysis and differential display RT-PCR to obtain evidence suggesting that in addition to a cellulosome-like mechanism, R. albus 8 possesses other mechanisms for adhesion to plant surfaces. Genome walking on either side of these differentially expressed transcripts has also resulted in two interesting observations: i) a relatively large number of genes with no matches in the current databases and; ii) the identification of genes with a high level of sequence identity to those identified, until now, in the archaebacteria. Genomics and proteomics will also accelerate our understanding of microbial interactions, and allow a greater degree of in situ analyses in the future. The challenge is to utilize genomics and proteomics to improve our fundamental understanding of microbial physiology, diversity and ecology, and overcome constraints to ruminal function.

• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.178-183
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• 2007

China has numerous native domestic goat breeds, but so far there has been no extensive study on genetic diversity, population demographic history, and origin of Chinese goats. To determine the origin and genetic diversity of Chinese goats, we analyzed the complete mtDNA D-loop sequences of 183 goats from 13 breeds. The haplotype diversity value found in each breed ranged from 0.9333 to 1.0000. The nucleotide diversity value ranged from 0.006337 to 0.025194. Our results showed that there were four mtDNA lineages (A, B, C and D), in which lineage A was predominant, lineage B was moderate, and lineages C and D were at low frequencies. Lineages C and D were observed only in the Tibetan breed. The results revealed multiple maternal origins of Chinese domestic goats. There was weaker geographical structuring in the 13 Chinese goat populations, which suggested that there existed high gene flow among goat populations caused by the extensive transportation of goats in the course of history.

• 한국정보통신학회논문지
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• 제8권2호
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• pp.281-288
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• 2004

본 논문에서는 저속 페이딩 환경 하에서 다중 심볼 차동 복조기의 다이버시티 수신 방법에 대하여 연구한다. MSDD(Multiple Symbol Differential Detection)를 이용하여 다이버시티 수신을 할 경우 복조 블럭의 길이를 크게 할수록 차동 부호화된 MPSK의 Maxim -Ratio-Combining(MRC) 다이버시티 수신기 성능에 수렴하지만 복잡도가 지수적으로 증가하여 현실적으로 구현이 불가능하다. 본 논문에서는 MSDD 수신기에 입력하기 전에 수신 신호들을 정렬 시켜서 결합하는 pre-combining 방식을 제안하였다. 여기서 제안된 pre-combined MSDD 다이버시티 수신기는 준최적 수신기로서 수신기의 복잡도가 복조 블록의 길이에 선형적으로 증가하는 효율적인 MSDD 복조를 가능케 한다. 따라서 고속의 버스트 모뎀과 같이 동기 복조의 어려움이 있을 경우, 채널에 대한 정보에 의존치 않고도 다이버시티 수신을 할 수 있으며 기존의 차동 복조 방식에 비하여 큰 성능 향상을 보여준다.

• Animal Systematics, Evolution and Diversity
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• 제31권2호
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• pp.135-138
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• 2015

An asteroid specimen was collected in adjacent water of Gisamun, Gangwon-do in the East Sea, Korea at a depth of 170 m by fishing net at May 2013. It was identified as Nearchaster (Nearchaster) pedicellaris (Fisher, 1910) belonging to family Benthopectinidae of order Notomyotida, which was new to the Korean fauna. The genus, family, and order of this species were also new to Korean waters. The partial sequence of mitochodrial cytochrome c oxidase subunit 1 (CO1) was determined for the first time and registered at GenBank.

• International Journal of Industrial Entomology and Biomaterials
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• 제15권1호
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• pp.47-58
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• 2007

The tiny dragonfly, Nannophya pygmaea(Odonata: Libellulidae) is one the smallest dragonflies in the world and listed as a second-degree endangered wild animal and plant in Korea. For the long-term conservation of such endangered species, an investigation on nation-wide genetic magnitude and nature of genetic diversity is required as a part of conservation strategy. We, thus, sequenced a portion of mitochondrial COI gene, corresponding to "DNA Barcode" region(658 bp) from 68 N. pygmaea individuals collected over six habitats in Korea. The sequence data were used to investigate genetic diversity within populations and species, geographic variation within species, phylogeographic relationship among populations, and phylogenetic relationship among haplotypes. Phylogenetic analysis and uncorrected pairwise distance estimate showed overall low genetic diversity within species. Regionally, populations in southern localities such as Gangjin and Gokseong in Jeollanamdo Province showed somewhat higher genetic diversity estimates than those of remaining regions in Korean peninsula. Although geographic populations of N. pygmaea were subdivided into two groups, distance- or region-based geographic partition was not observed.

• Parasites, Hosts and Diseases
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• 제52권2호
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• pp.205-209
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• 2014

Echinococcus granulosus is the causative agent of cystic echinococcosis with medical and veterinary importance in China. Our main objective was to discuss the genotypes and genetic diversity of E. granulosus present in domestic animals and humans in western China. A total of 45 hydatid cyst samples were collected from sheep, humans, and a yak and subjected to an analysis of the sequences of mitochondrial cytochrome b (cytb) gene. The amplified PCR product for all samples was a 1,068 bp band. The phylogenetic analysis showed that all 45 samples were identified as E. granulosus (genotype G1). Ten haplotypes were detected among the samples, with the main haplotype being H1. The haplotype diversity was 0.626, while the nucleotide diversity was 0.001. These results suggested that genetic diversity was low among our samples collected from the west of China based on cytb gene analysis. These findings may provide more information on molecular characteristics of E. granulosus from this Chinese region.

• Journal of Microbiology and Biotechnology
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• 제19권9호
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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.