• Animal cells and systems
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• v.8 no.3
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• pp.231-233
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• 2004

Sequences of cytochrome b gene and control region of mitochondrial DNA from Korean common otters (Lutra lutra lutra L.) were examined to provide the genetic information for the conservation of this subspecies. Two haplotypes and one haplotype were revealed in cytochrome b gene and control region, respectively. The available sequences of European common otter (L. l. lutra) from GenBank were compared together with those of Korean common otter in order to determine the degree of sequence variation between them. In cytochrome b gene sequences, two haplotypes from Korea and two haplotypes of Europe showed differences in 12 of 1,045 sites. The Tamura-Nei nucleotide distances between two European haplotypes was 0.10% and those between two Korean haplotypes was also 0.10%, but those between Korean haplotypes and European ones ranged from 0.96% to 1.16%. In the control region, one Korean haplotype and seven European ones showed differences in seven of 300 sites; the Tamura-Nei distances among seven European haplotypes were 0.34% to 1.01%, but those between Korean haplotype and European ones ranged from 1.01% to 1.69%. Although further molecular and morphological studies with specimens from eastern Asia including Amur region and northeast China are needed, it is possible that the Korean common otter might be closer or identical to the far-eastern Asian common otter, L. l. amurensis Dybowski.

• Advances in aircraft and spacecraft science
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• v.4 no.6
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• pp.701-709
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• 2017

One of the components that used in the satellite thermal control subsystem is the Mechanically Pumped Fluid Loop (MPFL) system; this system mostly used in geosynchronous orbit (GEO) satellites, and can transfer heat from a hot point to a cold point using the fluid which circulated in a closed loop. Heat radiates to the deep space at the cold plate to cool down the fluid temperature. In this research, the radiative heatexchanger (RHX) for a MPFL system is optimized. The genetic algorithm has been used for minimizing the total mass and pressure drop by considering a constant transferred heat rate at the heat exchanger. The optimization has been done in two cases. In case I, two parameters are considered as a goal function, so optimization is performed using NSGA-II method. Results of optimization are shown in the pareto diagram. In case II, the diameter of pipe is considered constant, so the optimized value for distances of the parallel pipes is obtained by using the genetic algorithm, in which the system has the least total mass. Results show that in the RHX, by increasing the pipe diameter, pressure drop decreases and total mass increases. Also by considering a constant value for pipe diameter, an optimum distance between pipes and pipe length are obtained in which the system has a minimum mass.

• Development and Reproduction
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• v.12 no.2
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• pp.151-158
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• 2008

The variability within and between Korean pond-smelt (Hypomesus nipponensis; KPS) and Canadian capelin (Mallotus villosus; CCP) were studied in order to clarify the genetic distances and differences. The dendrogram obtained by the seven primers indicates cluster 1 (KOREAN 01$\sim$KOREAN 11) and cluster 2 (CANADIAN 12$\sim$CANADIAN 22). The longest genetic distance displaying significant molecular differences was found to exist between individuals in the two geographic species of Osmeridae, between individuals' no. 10 of Korean and no. 18 of Canadian (0.686). 121 unique shared loci to each species, with an average of 17.3 per primer, were observed in the KPS species, and 264 loci, with an average of 37.7 per primer, were observed in the CCP species. 77 shared loci by the two species, with an average of 11.0 per primer, were observed in the two fish species. RAPD analysis showed that the KPS species was more genetically diverse than the CCP species. KPS species may have high levels of genomic DNA variability owing to the introduction of the wild individuals from the other sites to sampling sites although it may be the geographically diverse distribution of this species. As stated above, the existence of species discrimination and genetic variability between the KPS and the CCP species was identified by RAPD analysis.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.8
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• pp.1047-1052
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• 2004

The genomes of Chinese native chicken populations were screened using microsatellites as molecular markers. A total of, 528 individuals comprisede12 Chinese native chicken populations were typed for 7 microsatellite markers covering 5 linkage groups and genetic variations and genetic distances were also determined. In the 7 microsatellite loci, the number of alleles ranged from 2 to 7 per locus and the mean number of alleles was 4.6 per locus. By using fuzzy cluster, 12 Chinese native chicken populations were divided into three clusters. The first cluster comprised Taihe Silkies, Henan Game Chicken, Langshan Chicken, Dagu Chicken, Xiaoshan Chicken, Beijing Fatty Chicken and Luyuan Chicken. The second cluster included Chahua Chicken, Tibetan Chicken, Xianju Chicken and Baier Chicken. Gushi Chicken formed a separate cluster and demonstrated a long distance when comparing with other chicken populations.

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.4
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• pp.357-364
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• 1995

A biochemical genetic study on blood enzyme/protein systems in some breeds/crosses of sheep in Malaysia was carried out using horizontal starch gel electrophoresis. Blood samples were collected from 435 sheep, representing 8 breeds/crosses. These included 5 wool sheep breeds (Thai Longtail, wiltshire, Suffolk, Dorsimal and cMBLx), 1 hair sheep breed (Barbados Blackbelly) and 2 hybrids between wool sheep and hair sheep (Cameroon ${\times}$ Thai Longtail and Bali Bali ${\times}$ Malin). Twenty loci systems were examined. Of these, ten ($HB{\beta}$, ALB, TF, XP, CAT, DIA1, EsA, GPI, ME and NP) exhibited genetic variation whereas the other ten (AAT, CA, DIA2, ${\alpha}GLO$, ${\alpha}GLU$, LDH, MDH, PEP[leu-gly-gly], 6PGD and SOD) were monomorphic. The allelic frequencies which were obtained in 10 polymorphic markers are assessed and compared with the results obtained by previous workers. The estimations of inbreeding coefficient, intrabreed variation and breed relationships have been critically discussed and are used to reveal some important recommendations.

• Korean Journal of Agricultural Science
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• v.23 no.1
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• pp.99-107
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• 1996

Eighteen nuclear probes were used to examine RFLP(restriction fragment length polymorphism) between six species of Artemisia spp. of Korea. Total DNA from six different species of Artemisia was separately cut with three restrict enzymes. The PstI enzyme was showed to reduce the variation of polymorphisms than the other two enzymes(EcoRl and BamHI). The genetic variation of polymorphism was similar between the Dhewegiki-ssug and Cham-ssug. RAPD analysis was applied to the same six species of Artemisia spp. in order to assess the degree of DNA polymorphism within the Artemisia genus. Six species of Artemisia were evaluated for variation using a set of 11 random 10-mer primers. Nine out of the eleven primers revealed scorable polymorphisms between six species of Artemisia spp. Genetic distances between each of the species were calculated and cluster analysis was used to generate a dendrogram showing phylogenetic relationships between them This result indicates that molecular markers will be more usable in intraspecific study of Artemisia spp. than isoenzyme markers.

• Journal of the Semiconductor & Display Technology
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• v.20 no.4
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• pp.16-22
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• 2021

We search for an appropriate initial adsorption coordination of precursor on surface by using genetic algorithm (GA) and density functional theory. SiH₄ and Al(CH₃)₃ as precursor, and OH-terminated Si (001) as surface are used for this study. Selection, crossover, and mutation as hyperparameters of GA are applied to search for the adsorption coordination of the precursors on the surface as a function of generation. Bond distances between precursors and the surface are used to explain the adsorption behavior of the precursors.

• Journal of Life Science
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• v.18 no.10
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• pp.1325-1330
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• 2008

Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

• Journal of Life Science
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• v.18 no.11
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• pp.1465-1470
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• 2008

Salix koriyanagi is a deciduous shrub and native to Korea. The spatial distribution of multilocus allelic frequencies and geographical distances of the natural population in upper swampy area at the Namgang River in Korea were studied. The species showed a significant positive and negative spatial autocorrelation according to geographical distances as measured by Moran's I. Genetic similarity of individuals was found among subpopulations at up to a scale of a 12 m distance, and this was partly due to a combination of allelic frequencies, and therefore, a significant spatial autocorrelation was composed of a scale of 12 m intervals. Within S. koriyanagi in swampy area at the Namgang River, a strong spatial structure was observed for allozyme markers, indicating a migration within subpopulations.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.11
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• pp.1520-1522
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• 2001

Relationship among Tibetan cashmere goats, Inner Mongolia cashmere goats and Liaoning cashmere goats was studied using the technique of random amplified polymorphic DNA (RAPD). One primer and four primer combinations were screened. With the five primers and primer combinations, DNA fragments were amplified from the three breeds. Each breed has 28 samples. According to their RAPD fingerprint maps, the Nei's (1972) standard genetic distance was: 0.0876 between Tibetan cashmere goats and Inner Mongolia cashmere goats, 0.1601 between Tibetan cashmere goats and Liaoning cashmere goats, 0.0803 between the Inner Mongolia cashmere goats and Liaoning cashmere goats. It coincides with their geographic location. The genetic heterogeneity of Tibetan cashmere goats, Inner Mongolia cashmere goats and Liaoning cashmere goats is 0.3266, 0.2622 and 0.2475 respectively. It is also consistent with their development history.