• Asia Marketing Journal
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• v.8 no.1
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• pp.1-17
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• 2006

A couple of previous studies have warned against the use of homogeneous choice models in assessing the effect of reference price since unaccounted for response heterogeneity may result in spurious reference price effects(Chang, Siddarth and Weinberg 1999; Bell and Lattin 2000). According to Meyer and Kahn(1991), not accounting for consideration set heterogeneity may also bias the effect parameters in the choice model. Therefore, failure to account for these two sources of bias, in fact, have cast doubt on the empirical support for reference price effects in general. In view of aforementioned potential sources of bias, the author investigates the robustness of loss aversion effect in the reference-dependent model after accounting for heterogeneity in response as well as consideration set. The proposed model defines individual household's consideration set based on the posterior distribution of preference obtained from the Empirical Bayes approach. In addition, the same posterior distribution is used to form household-specific reference prices. Response heterogeneity correction is carried out via the Latent Class approach. The proposed model outperforms the Reference-Dependent model that includes the reference price measure most often employed in the previous studies. This implies that as a way of simplifying decision task, consumers restrict their consideration set to a subset of available brands not only in making a brand choice but also in forming reference prices.

• Journal of Life Science
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• v.10 no.1
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• pp.14-19
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• 2000

Variation at 25 allozyme loci in Korean wateralder (Alnus hirsuta Rupr.) from nine distinct populations was measured to estimate the amount and pattern of genetic diversity and population structure. The mean genetic diversity within population was 0.166. Korean alder populations have slightly high levels of genetic diversity compared to those present in associated temperature-zone species and two Canadian alder species. Among population s genetic differentiation accounted for an significant 9% of the total variation. High gene flow(Nm=2.63) was observed. Analysis of fixation indices, calculated for all polymorphic loci in each population, showed a substantial deficiency of heterozygotes relative to Hardy-Weinberg expectations. The mean GST value A. hirsuta in Korea (GST = 0.087) is similar to those of A. rogosa in Canada (GST = 0.052). These low values of GST in two countries. reflecting little spatial genetic differentiation, may indicate extensive gene flow (via pollen and/or seeds) and/or recent colonization. These factors reduce the effect of geographic isolation of breeding and the chance for genetic divergence. A pattern of increasing is observed with increasing rainfall per year. Regression analysis indicates that 54% (F = 4.67) of the variability observed can be explained by this relationship.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1366-1368
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• 2004

The Mafriwal dairy cattle was developed to meet the demands of the Malaysian dairy Industry. Although there are reports on its production and reproductive performance, there has been no work on its molecular characterization. This study was conducted to characterize the Mafriwal dairy cattle using microsatellite markers. Fifty two microsatellite loci were analysed for forty Mafriwal dairy cows kept at Institut Haiwan Kluang, Malaysia. The study showed two microsatellite loci to be monomorphic. Allele frequencies for the polymorphic loci ranged from 0.01 to 0.31. Genotype frequencies ranged from 0.03 to 0.33. The mean overall heterozygosity was 0.79. All polymorphic microsatellite loci deviated significantly (p<0.01) from Hardy-Weinberg equilibrium. The Mafriwal dairy cattle showed high genetic variability despite being a nucleus herd and artificial insemination being practiced.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.6
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• pp.752-756
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• 2011

Polymorphism of the second exon of the caprine leukocyte antigen-DRB3 gene (CLA-$DRB3^*02$) was investigated in this study. The 285 bp PCR product of 258 individuals from 10 domestic goat breeds in Southwest China was digested with restriction endonucleases PstI and HaeIII and then genotyped. Three alleles and 4 restriction digestion profiles were distinguished by digestion of the PCR fragment by PstI, and 8 alleles and 13 genotypes by HaeIII. For HaeIII restriction enzyme sites, the Chi-square ($X^2$) test showed that all goat breeds in this study did not fit with the Hardy-Weinberg equilibrium (p<0.01 or p<0.05). The highly polymorphic nature of CLA-$DRB3^*02$ was demonstrated and the ranges of gene heterozygosity (He) and polymorphism information content (PIC) were 0.36-0.63 and 0.32-0.55, respectively. Clustering analysis showed that the 10 goat breeds clustered into two groups and Dazu Black goat had a close genetic relationship with Chengdu Grey, Jintang Black and Nanjiang Yellow goats.

• Journal of The Korean Astronomical Society
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• v.35 no.1
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• pp.41-57
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• 2002

We have written a code called QDM_sca, which numerically solves the problem of radiative transfer in an anisotropically scattering, spherical atmosphere. First we formulate the problem as a second order differential equation of a quasi-diffusion type. We then apply a three-point finite differencing to the resulting differential equation and transform it to a tri-diagonal system of simultaneous linear equations. After boundary conditions are implemented in the tri-diagonal system, the QDM_sca radiative code fixes the field of specific intensity at every point in the atmosphere. As an application example, we used the code to calculate the brightness of atmospheric diffuse light(ADL) as a function of zenith distance, which plays a pivotal role in reducing the zodiacal light brightness from night sky observations. On the basis of this ADL calculation, frequent uses of effective extinction optical depth have been fully justified in correcting the atmospheric extinction for such extended sources as zodiacal light, integrated starlight and diffuse galactic light. The code will be available on request.

• Journal of Plant Biology
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• v.37 no.2
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• pp.141-149
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• 1994

Levels of genetic diversity, population genetic structure, and gene flow in Hosta yingeri, a herbaceous perennial endemic to Taehuksan, Sohuksan, and Hong Islands, were investigated. Starch gel electrophoresis was conducted on leaves for 101 plants collected from three populations. Although the distribution of thespecies is restricted in the islands, it maintains high levels of genetic variatin; 64% of polymorphic loci in at least one population (Ps), the mean number of alleles per locus (Ap) of 1.92, and the mean effective number of alleles per locus (Aep) of 1.52. Overall, mean genetic diversity (Hep=0.250) was substantially higher than mean estimate for species with very similarlife history traits (0.102). Large populaton size, the persistence of multiple generations within populations, high fecundity, predominantly outcrossing breeding system, large size of pollinator visitation areas may be explanatory factors contributing the higher level of genetic diversity maintained within populations. Analysis of fixation indices showed an overall slight excess of heterozygotes (mean FIS=-0.066) relative to Hardy-Weinberg expectations, which may in part be due to the near self-incompatible breeding system in the species. Significant differences in allele frequencies among populaitns were found for 14 out of 16 polymorphic loci (P<0.05). Slightly more than 80% of the total variation in the species was common to all populations (GST=0.198). As expected, indirect estimate of the number of migrants per generation (Nm=0.45, calculated from mean GST) and nine private alleles found in the three populations indicate that gene movement among three isolated island populations was low.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.5
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• pp.633-637
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• 2007

Genetic variation in Nilagiri sheep, the only apparel wool breed in South India was studied using 25 FAO recommended ovine-specific microsatellite markers. The number of observed alleles ranged from 3 to 8 with a mean of 5 across all loci. The size of alleles ranged from 72 to 228 bp. The frequency of alleles ranged from 0.0104 to 0.5781. In total, 125 alleles were observed at the 25 loci studied. The effective number of alleles ranged from 2.18 to 6.49. The mean number of effective alleles was 3.84 across all loci. All the 25 loci were found to be highly polymorphic. The PIC values ranged from 0.4587 to 0.8277 with a mean of 0.6485. Of 25 microsatellites studied, 17 were in Hardy-Weinberg Equilibrium proportions. The observed heterozygosity ranged from 0.4222 to 1.000 with a mean value of 0.7610 whereas the expected heterozygosity ranged from 0.5415 to 0.8459 with a mean value of 0.7213. Except six loci, the other loci revealed negative within-population inbreeding estimates (FIS) indicating excess of heterozygotes in the population of Nilagiri sheep.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.466-470
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• 2008

Microsatellite DNA markers were used to investigate the genetic diversity and population structure of Pacific abalone Haliotis discus hannai collected from six locations (Uljin, Ulsan, Daechon, Taean, Wando, and Yosu) where hatchery-produced abalone have been released intensively. There was no distinguishable difference in the observed and expected heterozygosities between the six populations and a cultured population. However, there was a difference in the number of alleles per locus: 12.8 for the cultured population and 13.8 to 15.8 for the six populations. The proportion of stocked abalone ranged from 41.1 to 92.7% for wild-caught populations with a decreasing tendency of alleles per locus for an increasing proportion of stocked abalone. A departure from Hardy-Weinberg equilibrium (HWE) assessed using the Markov chain procedure (P<0.05) was observed in the six populations and cultured population at loci Hdh145 and Hdh5l2. The pairwise Fst test (P<0.05) showed a significant difference between the Uljin and Ulsan populations and four remaining populations (Wando, Daechon, Yosu, and the cultured population), among which the Wando population differed less than the other three populations (Daechon, Yosu, and the cultured population).

• Animal cells and systems
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• v.9 no.2
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• pp.95-100
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• 2005

Essential hypertension results from the complex interaction between genetic and environmental factors. A C825T polymorphism of the gene encoding G-protein ${\beta}3$ subunit (GNB3), associated with enhanced G-protein coupled signaling and increased $Na^+-H^+$ exchanger, has been implicated in the development of essential hypertension in several human populations, especially in Caucasian population. We examined the disease relevance of this candidate gene by performing an association study in a study group of Korean heritage. Participants comprised 109 essential hypertensives and 109 normotensives, respectively. Genotyping was performed with PCR-BsaJI restriction digestion method. Observed genotype frequencies were in Hardy-Weinberg equilibrium in all groups. Genotype and allele frequencies did not differ significantly between normotensives and essential hypertensives (P>0.05). However, the serum total cholesterol (TC) and LDL-cholesterol levels were significantly higher in subjects with the TT genotype compared to those with the CC or CT genotypes in normotensives of our study subjects (P<0.05). Thus, these results suggest that GNB3/C825T polymorphism might be significantly associated with abnormality in serum lipid metabolism.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.1
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• pp.30-38
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• 2017

The red-spotted apollo butterfly, Parnassius bremeri Bremer, 1864 (Lepidoptera: Papilionidae), is an endangered species in South Korea. Development and application of molecular markers to assess population genetics perspectives can be used as a basis to establish effective conservation strategies. In this study, we developed 12 microsatellite markers specific to P. bremeri using Illumina paired-end sequencing and applied the markers to South Korean populations to understand population characteristics. Genotyping of 40 P. bremeri individuals from three localities showed that at each locus, the observed number of alleles ranged from 6 to 22 and the observed and expected heterozygosities were 0.500-1.00 and 0.465 to 0.851, respectively. Significant deviation from the Hardy-Weinberg equilibrium was not observed in all loci studied. The population based $F_{ST}$ and $R_{ST}$ collectively suggest that at least the Samcheok population in northernmost Gangwon Province has a significant divergence from the remaining two populations (P < 0.01), and this result is also reflected in the forewing length. Further studies with an increased sample size will be necessary to draw robust conclusions and devise conservation strategies.