• Animal Bioscience
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• 제34권7호
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• pp.1105-1115
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• 2021

Objective: To conserve and utilize the genetic resources of a traditional Chinese indigenous pig breed, Liangshan pig, we assessed the genetic diversity, genetic structure, and genetic distance in this study. Methods: We used 50K single nucleotide polymorphism (SNP) chip for SNP detection of 139 individuals in the Liangshan Pig Conservation Farm. Results: The genetically closed conserved population consisted of five overlapping generations, and the total effective content of the population (Ne) was 15. The whole population was divided into five boar families and one non-boar family. Among them, the effective size of each generation subpopulation continuously decreased. However, the proportion of polymorphic markers (P_N) first decreased and then increased. The average genetic distance of these 139 Liangshan pigs was 0.2823±0.0259, and the average genetic distance of the 14 boars was 0.2723±0.0384. Thus, it can be deduced that the genetic distance changed from generation to generation. In the conserved population, 983 runs of homozygosity (ROH) were detected, and the majority of ROH (80%) were within 100 Mb. The inbreeding coefficient calculated based on ROH showed an average value of 0.026 for the whole population. In addition, the inbreeding coefficient of each generation subpopulation initially increased and then decreased. In the pedigree of the whole conserved population, the error rate of paternal information was more than 11.35% while the maternal information was more than 2.13%. Conclusion: This molecular study of the population genetic structure of Liangshan pig showed loss of genetic diversity during the closed cross-generation reproduction process. It is necessary to improve the mating plan or introduce new outside blood to ensure long-term preservation of Liangshan pig.

• Mycobiology
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• 제46권2호
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• pp.92-100
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• 2018

The filamentous Ascomycota Colletotrichum gloeosporioides sensu lato is a fungus that has been reported worldwide as a causal agent of anthracnose disease in avocado and other crops. In Mexico, this species affects fruits from an early stage of development in the orchard until the post-harvest stage. Although fungicides are continuously applied to control Colletotrichum species, pericarp cankers and soft rot mesocarp in fruits are still frequently observed. Considering the lack of a precise description of the causative agent, the aim of the current study was to determine the pathogens involved in this symptomatology. Twenty-four isolates were consistently obtained from the pericarp of avocado fruits cv. "Hass" collected in the central avocado-producing area of Mexico. Morphological features such as colony growth, conidia size, and mycelial appressorium were assessed. Bayesian multilocus phylogenetic analyses were performed using amplified sequences of the internal transcribed spacer region of the nuclear ribosomal DNA; actin, chitin synthase, glyceraldehyde-3-phosphate dehydrogenase partial genes; and APn2-Mat1-2 intergenic spacer and mating type Mat1-2 partial gene from the nine selected isolates. In addition, fruits were inoculated with a conidial suspension and reproducible symptoms confirmed the presence of Colletotrichum fructicola in this area. This pathogenic species can now be added to those previously reported in the country, such as C. acutatum, C. boninense, C. godetiae, C. gloeosporioides, and C. karstii. Disease management programs to reduce the incidence of anthracnose should include C. fructicola to determine its response to fungicides that are routinely applied, considering that the appearance of new species is affecting the commercial quality of the fruits and shifting the original population structure.

• 한국통신학회논문지
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• 제39A권6호
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• pp.357-364
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• 2014

본 논문은 반사필터를 사용하여 FTTH-PON의 원격제어 시스템을 다루고 있다. 기존의 FTTH-PON방식은 광케이블 고장과 수동분기소자(Splitter)의 품질 저하가 발생하는 것을 실시간 인지 할 수 없다. 본 연구에서는 이를 해결하기 위해서 광섬유 브래그 격자 원리를 이용한 반사필터를 개발하여 간선망과 Splitter를 감시 할 수 있게 하였다. 반사필터는 광케이블 밴딩, 커넥터 상태와 스플리터의 품질이 점진적으로 저하되는 것을 모니터링 하고 광케이블 고장, 수동 광분배기(Splitter) 등의 고장 위치를 확인하여 OLT측에 경보를 보내서 중앙관제에서 감시할 수 있는 시스템이다. 즉, 기존 통신 국사 측 파장분기 결합부(Coupler)를 이용해 1개의 광심선으로 live 파장과 감시용 파장을 2개로 보내어 가입자 측 장치인 모뎀과 집선 스위치에 반사필터를 사용하여 원격으로 광선로를 감시하는 시스템에 관한 연구이다. 이러한 반사필터의 개발로 인해 광선로 평균 고장처리 시간 단축과 효율적 유지보수를 할 수 있을 것으로 기대한다.

• 대한기계학회논문집A
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• 제34권7호
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• pp.805-811
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• 2010

체결류는 일반 제품을 설계할 때 널리 사용되며, 일반 부품에 비하여 표준화가 잘 되어 규격화 되어있다는 특징이 있다. 그래서 체결류를 설계할 때에는 먼저 수식을 사용하여 원하는 기능을 가진 체결류를 계산하고, 최종 사양은 규격에서 계산된 용량을 만족하는 것을 선택한다. 이 연구에서는 이러한 체결류 설계의 특징을 살리며 삼차원 CAD 시스템에서 편리하게 체결류 설계를 할 수 있는 시스템에 대한 연구를 수행하였다. 이 시스템에서 자동으로 설계하기에 적합한 체결류 형상을 정의하였으며, 체결류 설계에 필요한 설계 인자와 형상 치수를 규격에서 추출하여 데이터베이스를 구축하였다. 또한 체결류를 설계할 때 사용하는 설계식을 구현하여 설계식의 입력 인자와 출력 인자를 규격으로부터 추출한 데이터베이스 및 형상 치수와 연결시켰다.

• The Korean Journal of Ecology
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• 제23권1호
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• pp.17-23
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• 2000

소나무(Pinus densiflora), 쥐똥나무(Ligustrum obtusifolium), 그리고 오리나무(Alnus japonica)의 공간적 상관관계를 생태적, 유전적 분석을 통해 살펴보았다. 이 가운데, 소나무와 쥐똥나무의 생태적 공간관계는 양의 상관관계를 나타낸 반면, 쥐똥나무와 오리나무는 음의 상관관계를 나타내었다. Moran의 I값과 표준편차(SND: standard normal deviate)값에 의하면 소나무는 18 m에서 집단구조를 형성 한 반면, 쥐똥나무는 12.5 m간격으로 집단구조가 형성되어 있었다. 오리나무는 명확한 집단구조가 결여되어 있었다. 소나무와 쥐똥나무의 두 종간의 공간구조에 있어, 유전적으로 유의한 상관관계가 형성 된 것은 소나무의 수관이 비교적 좁고, 적절한 피음효과를 제공함으로써, 쥐똥나무의 생육에 기여하였기 때문으로 생각된다. 오리나무와 쥐똥나무의 경우, 광합성과 관련한 수광경쟁에서 비교적 넓은 오리나무의 수관 때문에,두 종간의 동소적 관계가 방해되는 것으로 추정된다.

• Genomics & Informatics
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• 제4권4호
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• pp.147-160
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• 2006

GATA transcription factors are widespread eukaryotic regulators whose DNA-binding domain is a class IV zinc finger motif in the form $CX_{2}CX_{17-20}CX_{2}C$followed by a basic region. In fungi, they act as transcriptional activators or repressors in several different processes, ranging from nitrogen source utilization to mating-type switching. Using an in-house bioinformatics portal system, we surveyed 50 fungal and 9 out-group genomes and identified 396 putative fungal GATA transcription factors. The proportion of GATA transcription factors within a genome varied among taxonomic lineages. Subsequent analyses of phylogenetic relationships among the fungal GATA transcription factors, as well as a study of their domain architecture and gene structure, demonstrated high degrees of conservation in type IVa and type IVb zinc finger motifs and the existence of distinctive clusters at least at the level of subphylum. The SFH1 subgroup with a 20-residue loop was newly identified, in addition to six well-defined subgroups in the subphylum Pezizomycotina. Furthermore, a novel GATA motif with a 2f-residue loop ($CX_{2}CX_{21}CX_{2}C$, designated 'zinc finger type IVc') was discovered within the phylum Basidiomycota. Our results suggest that fungal GATA factors might have undergone multiple distinct modes of evolution resulting in diversified cellular modulation in fungi.

• BMB Reports
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• 제41권9호
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• pp.651-656
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• 2008

A mouse with cataract, Kec, was generated from N-ethyl-N-nitrosourea (ENU) mutagenesis. Cataract in the Kec mouse was observable at about 5 weeks after birth and this gradually progressed to become completely opaque by 12 weeks. Dissection microscopy revealed that vacuoles with a radial or irregular shape were located primarily in the cortex of the posterior and equatorial regions of the lens. At the late stage, the lens structure was distorted, but not ruptured. This cataract phenotype was inherited in an autosomal recessive manner. We performed a genetic linkage analysis using 133 mutant and 67 normal mice produced by mating Kec mutant (BALB/c) and F1 (C57BL/6 $\times$ Kec) mice. The Kec locus was mapped to the 3 cM region encompassed by D14Mit34 and D14Mit69. In addition we excluded coding sequences of 9 genes including Rcbtb2, P2ry5, Itm2b, Med4, Nudt15, Esd, Lcp1, Slc25a30, and 2810032E02Rik as the candidate gene that causes cataract in the Kec mouse.

• 한국발생생물학회지:발생과생식
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• 제18권1호
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• pp.25-31
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• 2014

This study was investigated spawning behavior, structure of egg masses and egg development in Aplysia kurodai inhabiting the coastal waters of Jeju Island, Korea. The mating and courtship behavior of A. kurodai occurred in the form of unilateral copulating with chain formation. In chain copulation, only the first animal acted as a female; the second and succeeding animals acted as males (sperm donors) to the animals in front and as females to the animals behind. The fertilized eggs were packaged in capsules that are embedded in jelly to form a cylindrical string called an egg masses. The number of capsule per cm of the egg masses was 55 to 60 capsules and each capsule within the egg masses held 15 to 25 eggs. After spawning, the egg masses were bright yellow or orange in color. This egg masses color not changed until embryos developed into trochophore stage. Thereafter, as embryo developed from trochophore stage to veliger stage the egg masses color became brownish. The fertilized eggs were spherical, with a diameter of approximately $80{\pm}1{\mu}m$ at spawning. At 5 to 6 days after spawning, the embryo developed into trochophore stage and began to rotate within the egg capsule. In the trochophore stage, the precursor of the velum, called the prototroch or prevelum, developed. At 10 days after spawning, the prevelum is transformed into the velum, and the trochophore developed into veliger stage. Between 10 to 15 days after spawning, the veligers broke out of the egg capsule, and hatched as free-swimming larvae.

• Applied Microscopy
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• 제22권2호
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• pp.97-117
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• 1992

In order to study process of spermiogenesis of the Korean greater horseshoe bat, Rhinolophus ferrumequinum korai, the cycle of seminiferous epithelium was examined by the light and electron microscope and the following results were obtained based on the epithelial cell differentiation. 1. Spermiogenesis occurred from early July to mid-Octber, and spermatogenic activity was vigorous from mid-August to late September. Spermatocytes including spermatogonia were found to be degenerated in only July. It is deduced that the degeneration serves as the mechanism to regulate effective use of energy to prepare for mating and hibernating periods, and regulation of breeding cycle. 2. Spermiogenesis of the Korean greater horseshoe bat was divided according to differentiation of the cell structure, into Golgi, cap, acrosome, maturation and spermiation phases; Golgi, cap and spermiation phases were further divided into two steps of early and late phase respectively, and acrosome phase into three steps of early, mid and late phases, and maturation phase has only one step. Hence, the spermiogenesis consists of ten phases. The first research was done in this article on the changes of chromatin with nucleus, the time of appearance and disappearance of chromatin granules, in case of Korean greater horseshoe bat (Rhinolophus ferrumequinum korai). Chromatin granule began to be condensed in late Golgi and the condensation proceeded to form an irregular mass of a electron-dense chromatin in a form of circular cylinder in the center of nucleus at the phase of maturation. Finally, the chromatin condensation proceeded and perfect nucleus of sperm with homogeneous density was formed when the sperm was separated from Sertoli cell. Therefore, appearance and disappearance of chromatin granules occurred in the period of time between late Golgi and maturation phase, The tail of sperm began to develop in early cap phase, Numerous lipid droplets were obseved in the cytoplasm of spermatids during the maturation phase, which seemed to be used as energy source necessary to make mature sperm during spermiogenesis.

• 한국수산과학회지
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• 제44권6호
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• pp.701-708
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• 2011

The aim of the present study was to analyze the reductive cycle of the red marbled rockfish Sebastiscus tertius. The analysis was based on annual changes in the gonadosomatic index (GSI), the hepatosomatic index (HSI), histology of the gonadal structure, and plasma sex steroid hormone levels of adult fish from April 1997 to April 1998. GSI of females began to increase in February and peaked ($10.8{\pm}2.72$) in May. HIS levels ($3.41{\pm}0.49$) peaked in February and elevated plasma steroid hormones ($1.47{\pm}0.75$ ng/mL for estradiol-$17{\beta}$ ($E_2$) and $230.7{\pm}27.6$ pg/mL for testosterone (T)) were observed in April. However, in male fish, GSI levels started to increase in August and remained high until November ($0.21{\pm}0.05$). T levels were was also elevated in August and peaked in October ($188.1{\pm}43.5$ pg/mL) and November ($186.8{\pm}28.0$ pg/mL), but started to decline 1 month than the GSI. These results suggest that female ovoviviparious periods span from April to June and amle mating periods occur from November to February.