• Journal of Species Research
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• v.1 no.1
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• pp.100-103
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• 2012

Nutria Myocastor coypus is one of a well known invasive riparian mammal found species around world from North America to Eurasia and Africa. In South Korea, feral nutrias inhabit areas from the Nakdonggang and Namgang (River) to their tributaries and Upo Wetland where they have had devastating effects on environment. Nevertheless, there has been little research about nutrias in Korea. This study is to analyze the genetic structure of the nutria population in the Upo Wetland and identify the origin of the source populations. Twenty individuals from the Upo Wetland were genotyped using 25 microsatellite loci. When compared with another introduced population, that of the Blackwater Nation Wildlife Refuge in U.S., the Upo population contains considerable genetic variations. Tests for Hardy-Weinberg equilibrium and Bayesian clustering analysis suggest the Upo population is genetically structured and has at least two source populations. This preliminary study presents the need for further in-depth studies about this species which should combine genetic and ecological studies.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.2
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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.

• The Journal of the Korea institute of electronic communication sciences
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• v.10 no.6
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• pp.729-736
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• 2015

In this study, It was analyzed to estimate the origin from the collected disposable lighters with the printed company name and telephone number on the surface. Monitoring was done bimonthly from 2 areas of sandbar Coastline of Nakdong River Estuary(Jinu-do, Shinja-do) and 3 areas(Doomo beach, Heungnam beach, Yeocha beach) of Northeastern coast of Geoje-do. As a result of the monitoring, there were 166 lighters collected. Then, the monthly occurrence amount was concentrated in Jun, August. The origin of Disposable lighters that flowed in study area were mostly cause to the Nakdong River basin region and the coastal area where population densities are high.

• Journal of the Korean Home Economics Association
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• v.45 no.5
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• pp.51-61
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• 2007

The purpose of this study to determine the relationship between conflict coping behavior and the health of the family of origin in both male and female subjects currently in the dating population. The subjects consisted of 250 single male and female who had been dating for more than three months. A survey was used to collect the data and results of survey were analyzed by the SPSS PC 12.0 program. The study results are as follows; First, a conflict coping behavior with variable that is related to a socio-demographic was associated with significant differences in the manner of receiving assistance from external resource in terms of gender, education level, religion and age. The rational coping behavior showed significant changes in gender, and shrinking coping behavior was associated with also gender and sibling. Second, rational coping skills and shrinking coping skills, which are date-associated variables in comflict coping behavior, were influencing factors in the individuals' consideration of a future-relationship with their partner. Third, the health of the family of origin was associated with the manner in which the individual acquired external assistance and rational coping behavior.

• Proceedings of the Zoological Society Korea Conference
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• 1996.10a
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• pp.241.1-241
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• 1996

No Abstract, See Full Text

• Journal of Korean Society of Rural Planning
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• v.19 no.4
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• pp.203-212
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• 2013

The aging of farm households has caused serious problems such as productivity slowdown and aggravated income polarization in South Korea. Urban-to-rural migration has been recently suggested as a measure to attenuate the aging of rural population and other related problems. The inflow of migrants for farming can have a substantial effect on agriculture and rural communities while the natural adjustment of rural population caused by birth and death is slow. This paper forecasts population distribution of different provinces using the Origin-Destination (OD) analysis, taking into account both the size and directions of migration. In the analysis, nodes where the migration takes place are divided by the industrial sectors (agriculture and non-agriculture), regions, and ages. The results of a ten-year forecast shows that the aging of total population in most provinces will be intensified, but the portion of people over sixty will decrease in the agricultural sector. This finding implies that migration into rural areas, when occurring by a large extent, can mitigate the aging process and attendant problems.

• The Plant Pathology Journal
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• v.37 no.3
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• pp.280-290
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• 2021

Population genetic studies of Hemileia vastatrix have been conducted in order to describe the evolutionary dynamics of the pathogen and the disease epidemiology as consequence of changes in disease management and host distribution occurred in Peru after the 2013 epidemic. These analyses were performed by sequencing the internal transcribed spacers of the nuclear ribosomal DNA (rDNA-ITS) of H. vastatrix collected from two coffee growing areas in 2014 and 2018. H. vastatrix population showed high haplotype diversity (Hd = 0.9373 ± 0.0115) with a low nucleotide diversity (π = 0.00322 ± 0.00018). Likewise, AMOVA indicated that fungus population has behaved as a large population without structuring by geographical origin and sampling years (F_ST = 0.00180, P = 0.20053 and F_ST = 0.00241, P = 0.19693, respectively). Additionally, the haplotype network based on intraspecific phylogenetic analysis of H. vastatrix using Peruvian and NCBI sequences revealed that Peruvian ancestral haplotypes, which were maintained in time and space, would correspond to the reported sequences of the races II and XXII. This result suggests that no substantial changes have occurred through time in Peruvian Hemileia vastatrix population.

• Animal Systematics, Evolution and Diversity
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• v.39 no.4
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• pp.264-271
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• 2023

The edible jellyfish Rhopilema esculentum occurs in waters throughout northeastern Asia, including in Korea, China, and Japan. In Korean waters, R. esculentum has appeared in two regions (Gangwha and Muan). Based on the appearance of young medusae and coastal distribution records, these two regions may be key R. esculentum breeding sites. In the present study, we investigate and compare the genetic structure of R. esculentum in the two regions using mitochondrial sequences (16S ribosomal RNA and cytochrome c oxidase subunit I). The genetic diversity of the R. esculentum population at Ganghwa exceeded that of the population at Muan. Despite considerable geographic separation (400 km) between the two regions(Gangwha and Muan), our haplotype network suggests that the Gangwha and Muan populations of R. esculentum are related. The simple and monotonous genetic structure of the Muan population shows that R. esculentum emergence is relatively recent. In contrast, the Gangwha population shows evolution. Moreover, jellyfish of the Gangwha population are genetically diverse and remain constant despite environmental fluctuations in the Han River. The Gangwha area is considered to be the old origin of R. esculentum in Korea.

• Anatomy and Cell Biology
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• v.51 no.4
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• pp.243-250
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• 2018

Because of its embryonic origin, the thyroid gland is predisposed to multiple anatomical variations and developmental anomalies. These include the pyramidal lobe, the origin of levator glandular thyroidae, the absence of the isthmus, ectopic thyroid, accessory thyroid tissues, etc. These anatomical variations are clinically significant to surgeons, anatomists, and researchers. The present study was designed to report anatomical variations and developmental anomalies of the thyroid gland in Ethiopian population. The study was conducted on 40 cadavers used for routine dissection classes. The thyroid gland was exposed and observed for any variations and developmental anomalies. The length, width, and thickness of the lobes were measured using a vernier caliper. Differences in the incidence of pyramidal lobe and absence of the isthmus between sexes were tested using a Pearson chi-square test. The mean length, width, and thickness of the right lobe were 4.24 cm, 1.8 cm, and 1.6 cm, respectively, whereas it was 4.08 cm, 1.8 cm, and 1.6 cm, respectively for that of the left lobe. The pyramidal lobe was noted in 52.5% of the cadavers. The levator glandulae thyroidae were prevalent in 40% of the cadavers. The isthmus mainly overlies the 2nd to 4th tracheal rings and was absent in 7.5% of the cadavers. Accessory thyroid tissue and double pyramidal lobes were noted in 2.5% of the cadavers. Most of the variations of the thyroid gland were seen frequently in female but it was not statically significant. Different clinically important and rare variations of the thyroid gland were found.

• Journal of Animal Reproduction and Biotechnology
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• v.35 no.2
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• pp.198-206
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• 2020

Food and agricultural production sector, especially livestock production is vital for Mongolia's economic and social development. Domestic sheep play key roles for Mongolians, providing food (meat, milk) and raw materials (wool, sheepskin), but genetic diversity, origin of sheep populations in Mongolia have not been well studied. Studies of population genetic diversity is important research field in conservation and restoration of animal breeds and genetic resources. Therefore, this study aimed to investigate genetic characteristics and estimate origin through the analysis of mitochondrial DNA control region D-loop and Cytochrome b of Mongolian indigenous sheep (Mongolian native, Orkhon and Altanbulag) and one Europe sheep (Suffolk). As a result of there were found, 220 SNPs (Single nucleotide polymorphism) in the D-loop region, 28 SNPs in the Cytochrome B region, furthermore, 77 Haplotypes. The nucleotide diversity was only found in D-loop region (n = 0.0184). Phylogenetic analysis showed that 3 (A, B, and C) of 5 haplogroups of sheep have been identified in our research. Haplogroup C was only found in Mongolian indigenous sheep. Haplogroup D and E were not observed. As a result of haplogroups, haplogroup A was dominant (n = 46 of 94 sheeps), followed by haplogroup B (n = 36) and haplogroup C (n = 12). Sequence analysis showed that T deletion, insertion and heteroplasmy in D-loop region occurred at a high rate in Mongolian indigenous sheep population (T insertion = 47, T deletion = 83). The heteroplasmy, which has never been found in Mongolian sheep, has been newly discovered in this study. As a result, the Mongolian sheep varieties, which mainly derived from Asia, were in hybridization with European sheep varieties.