• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.769-774
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• 2006

Fractions of herd-year-season, sire by herd interaction, additive genetic and dominance genetic variances were estimated for milk production traits in Holsteins of Japan using Method R. Inbreeding depressions for milk production traits were also estimated. Estimated fractions of herd-year-season variances ranged from 0.056 to 0.074 for yield traits and from 0.033 to 0.035 for content traits. Estimated fractions of additive genetic variances to phenotypic variances (heritabilities across a herd in the narrow sense) were 0.306, 0.287, 0.273, 0.255, 0.723, 0.697 and 0.663 for milk, fat, SNF and protein yields, and fat, SNF and protein contents, respectively. Estimated fractions of dominance genetic variances ranged from 0.019 to 0.022 for yield traits and from 0.014 to 0.018 for content traits. Fractions of variances for sire by herd interaction were estimated to range from 0.020 to 0.025 for yield traits and 0.011 to 0.012 for content traits. Estimates of inbreeding depression for milk, fat, SNF and protein yields were -36.16 kg, -1.42 kg, -3.24 kg and -1.15 kg per 1% inbreeding for milk, fat, SNF and protein yields, respectively. Estimates of depression per 1% inbreeding for content traits were positive at $0.39{\times}10^{-3}%$, $0.31{\times}10^{-3}%$ and $0.82{\times}10^{-3}%$ for fat, SNF and protein contents, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.3
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• pp.309-314
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• 2006

The present investigation was undertaken to study the milkability characteristics of Holstein cows. Out of 6,660 initial records 4,607 records were finally included in the analysis after deleting some records with an abnormal range of values for the traits considered. These 4,607 Holstein cows belonged to a total of 122 herds located in a province in Korea. The 'LactoCorder' instrument was used to electronically record the milkability traits at the milking parlor. A total of 19 traits were studied which were broadly classified into milk yield, milking speed, milking time and the electrical conductivity related traits. The SAS 9.1 statistical software was used to carry out analyses. The average maximum milk flow per minute was 3.21 kg/min, while the average milking speed during the main milking process (DMHG) had a mean value of 2.30 kg/min. The total milk yield was 14.14 kg, 62% of which was milked during the first three minutes of the milking. The average total milking time was 8.23 min. Among the three phases of the main milking process, the time of stable milk flow had the longest time (2.97 min) followed by the time at the decline phase (2.62 min). The average time taken to reach the plateau phase was 1.08 min, which can still be reduced further through improved managemental practices. Among milk yield traits, milk yield during the first two (MG2) and three (MG3) minutes of milking had high positive correlation with milking speed traits and negative correlations with almost all the milking time traits except time of incline in milk flow from 0.5 kg/min till the attainment of the plateau phase (tAN). Milking speed traits had negative correlations with total milking time, time at main milking process, time at plateau and with the time at decline. Since there was medium to high negative correlation between the milking speed and the time at plateau, there is a need for selection of cows which have intermediate milking speed so that it could require less milking time and also the optimum (higher and longer) plateau time. Proper pre-stimulation and avoiding over milking will help in further reducing the milking time and thus will add to the net profit of the farmer.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.10
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• pp.1575-1580
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• 2018

Objective: This study was conducted to estimate the genetic parameters and breeding values of breast meat related traits of Pekin ducks. Selection response was also determined by using ultrasound breast muscle thickness (BMT) measurements in combination with bosom breadth (BB) and keel length (KL) values. Methods: The traits analyzed were breast meat weight (BMW), body weight (BW), breast meat percentage (BMP) and the three parameters of breast meat (BB, KL, and BMT). These measurements were derived from studying 15,781 Pekin ducks selected from 10 generations based on breast meat weight. Genetic parameters and breeding value were estimated for the analysis of the breeding process. Results: Estimated heritability of BMW and BMP were moderate (0.23 and 0.16, respectively), and heritability of BW was high (0.48). Other traits such as BB, KL, and BMT indicated moderate heritability ranging between 0.11 and 0.28. Significant phenotypic correlations of BMW with BW and BMP were discovered (p<0.05), and genetic correlations of BMW with BW and BMP were positive and high (0.83 and 0.66, respectively). It was noted that BMW had positive correlations with all the other traits. Generational average estimated breeding values of all traits increased substantially over the course of selection, which demonstrated that the ducks responded efficiently to increased breast meat yield after 10 generations of breeding. Conclusion: The results indicated that duck BMW had the potential to be increased through genetic selection with positive effects on BW and BMP. The ultrasound BMT, in combination with the measurement of BB and KL, is shown to be essential and effective in the process of high breast meat yield duck breeding.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1080-1084
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• 2002

Carcass characteristics of 241 crossbred pigs (Korean wild boars ${\times}$ Landrace sows) were analyzed to examine variations in fasted body weight (FASTWT), carcass weight (CARCWT), dressing percentage (DP), back fat thickness (BFT) and longissimus muscle weight (LMW), and to estimate genetic and phenotypic parameters using three different slaughter-end points. Covariates in the least squares full sib model were slaughter age, fasted body weight and back fat thickness of the carcass. Coefficient of variation was highest for BFT followed by LMW, CARCWT, FASTWT and DP in magnitude. Regressions of three covariates on traits were all linear. However, slaughter age was not significant as a linear covariate for five traits while FASTWT was significant for CARCWT and LMW and BFT was significant for all remaining traits. Genetic and phenotypic variation was considerably reduced by regressing FASTWT or BFT in the model. Heritability estimates of FASTWT, CARCWT, DP and BFT were 0.68, 0.61, 0.11 and 0.49, respectively, using slaughter age as covariate (model 1). Those of CARCWT, DP, BFT and LMW were 0.15, 0.15, 0.30 and 0.11, respectively, using FASTWT as covariate (model 2). Heritability estimates of the traits using LMW as covariate (model 3) were similar to the estimates from Model 1 except that the estimate of CARCWT was reduced to 0.39. Genetic or phenotypic correlations among FASTWT, CARCWT and BFT were all positive and moderate to high. Those between BFT and LMW were also positive and low to moderate. However, genetic and phenotypic correlations between DP and CARCWT were positive while those between DP and FASTWT were negative. It was suggested from this study that differences in carcass yield traits be determined using slaughter age or back fat thickness as slaughter-end point and carcass quality traits using fasted body weight as slaughter-end point.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.1 s.149
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• pp.146-156
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• 2006

The purpose of this study is to investigate the factors that influence consumers' adoption of performance infants' wear made of functional textiles. Based on Innovation Diffusion Model, product attributes, consumer traits, and communication characteristics were considered. A survey was carried out with a convenience sample of 241 housewives who have infants under 4 year-old, living in the Seoul metropolitan area. To analyze the data, SPSS 10.0 was used employing ANOVA, Duncan's post-hoc comparison, $X^2$, and f-test. The participants were classified into 4 groups based on their levels of adoption of performance infants' wear: No-Cognition, Negative Attitude, Positive Attitude, and Purchasing groups. There were significant differences among the four groups in terms of their perception of product attributes, communication characteristics, and personal traits. In terms of product attributes, the Positive Attitude group and Purchasing group showed higher perception of relative advantage, compatibility, trialability and observability than other groups. These groups were also high in terms of their tendency of actively seeking for additional product information, and particularly relied on the information from experts on TV or the Internet, personal experience posted on the Internet, or their own experience. Those who were in professional, well-educated and high income brackets were more likely to be Purchasing group than Positive Attitude group, which means once the positive attitude was formed they are likely to purchase the product.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.29 no.3
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• pp.144-148
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• 2018

Objectives: Previous studies have reported that internet addiction (IA) is associated with attention-deficit/hyperactivity disorder (ADHD) consistently. However, in terms of gender, there are controversial findings. We aimed to investigate the relation between IA and self-acknowledged ADHD traits among female college students in Japan. Methods: The study questionnaire consisted of questions about demographics, Adult ADHD Self-Report Scale-V1.1 Part A (ADHD screener) and Young's Internet Addiction Test (IAT). When four or more items are more frequent than the cut-off on ADHD screener, the subject was categorized into students with a positive ADHD screen. We defined students with total IAT score of 70 and higher as IA. Results: A total number of respondents was 369 (mean age: $19.0{\pm}0.7years$). Seventy-seven subjects were screened positive on ADHD screener (20.9%). Students with a positive ADHD screen scored significantly higher on the IAT ($54.2{\pm}14.2$ vs. $42.5{\pm}11.3$). The rates of IA in students with and without a positive ADHD screen were 18.2% and 1.0%, respectively. Conclusion: Results of this study demonstrated the relation between IA and self-evaluated ADHD traits among female college students in Japan. Appropriate education for students on how to use the internet properly will be necessary to prevent IA.

• Korean Journal of Cognitive Science
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• v.28 no.3
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• pp.173-191
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• 2017

The theories of cultural evolution hold subtly or clearly different stances about definition of culture, pattern of cultural evolution, biases that affect cultural evolution, and relationship between culture and organism. However, the cultural evolution theories have a common problem to solve: As the evolutionary theory of life tries to explain the early steps and the origin of life, the cultural evolution theories also must explain the early steps of the cultural evolution and the role of the human capability that makes cultural evolution possible. Therefore, explanations of the human's unique traits including the cultural ability are related to determine which one is the most plausible among many cultural evolution theories. Theories that tried to explain human uniqueness commonly depict the coevolution of gene (organism) and culture. We will explicitly call the niche construction theory and the dual inheritance theory the 'gene-culture co-evolutionary theory'. In these theories, the most important concept is the 'concept of positive feedback'. In this paper, we distinguish between core positive feedback and marginal positive feedback, according to whether the trait that the concept of positive feedback explains is the trait of human uniqueness. Both types of positive feedback effectively explain the generality of human uniqueness and the diversity of human traits driven by cultural groups. However, this positive feedback requires an end, in contrast to negative feedback which can be continued in order to maintain homeostasis. We argue that the co-evolutionary process in the gene-culture co-evolutionary theories include only the positive feedback, not covering the cultural evolution after the positive feedback. This thesis strives to define the coevolution concept more comprehensively by suggesting the potential relationships between gene and culture after the positive feedback.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1222-1228
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• 2016

The objective of this research was to estimate genetic parameters and trends for length of productive life (LPL), lifetime number of piglets born alive (LBA), lifetime number of piglets weaned (LPW), lifetime litter birth weight (LBW), and lifetime litter weaning weight (LWW) in a commercial swine farm in Northern Thailand. Data were gathered during a 24-year period from July 1989 to August 2013. A total of 3,109 phenotypic records from 2,271 Landrace (L) and 838 Yorkshire sows (Y) were analyzed. Variance and covariance components, heritabilities and correlations were estimated using an Average Information Restricted Maximum Likelihood (AIREML) procedure. The 5-trait animal model contained the fixed effects of first farrowing year-season, breed group, and age at first farrowing. Random effects were sow and residual. Estimates of heritabilities were medium for all five traits ($0.17{\pm}0.04$ for LPL and LBA to $0.20{\pm}0.04$ for LPW). Genetic correlations among these traits were high, positive, and favorable (p<0.05), ranging from $0.93{\pm}0.02$ (LPL-LWW) to $0.99{\pm}0.02$ (LPL-LPW). Sow genetic trends were non-significant for LPL and all lifetime production traits. Sire genetic trends were negative and significant for LPL ($-2.54{\pm}0.65d/yr$; p = 0.0007), LBA ($-0.12{\pm}0.04piglets/yr$; p = 0.0073), LPW ($-0.14{\pm}0.04piglets/yr$; p = 0.0037), LBW ($-0.13{\pm}0.06kg/yr$; p = 0.0487), and LWW ($-0.69{\pm}0.31kg/yr$; p = 0.0365). Dam genetic trends were positive, small and significant for all traits ($1.04{\pm}0.42d/yr$ for LPL, p = 0.0217; $0.16{\pm}0.03piglets/yr$ for LBA, p<0.0001; $0.12{\pm}0.03piglets/yr$ for LPW, p = 0.0002; $0.29{\pm}0.04kg/yr$ for LBW, p<0.0001 and $1.23{\pm}0.19kg/yr$ for LWW, p<0.0001). Thus, the selection program in this commercial herd managed to improve both LPL and lifetime productive traits in sires and dams. It was ineffective to improve LPL and lifetime productive traits in sows.

• International Journal of Industrial Entomology and Biomaterials
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• v.10 no.1
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• pp.61-64
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• 2005

General and specific combining ability effects of six bivoltine breeds of silkworm (Bombyx mori L.) were evaluated for six quantitative characters through diallel method wherein parents, $F_{1}s$ and reciprocals are involved. The breeds $APS_{11}\;and\;APS_{2}$ were found to be the best general combiners for most of the traits studied. The high estimates of specific combining ability (sca) variance (${\sigma}^{2}s$) compared to general combining ability (gca) variance (${\sigma}^{2}g$) indicated the predominant role of non-additive gene action in the control of all the characters. Positive sca effects for majority of the traits were expressed by the combinations $APS_{13}{\times}APS_6,\;APS_{13}{\times}APS_2,\;APS_{11}{\times}APS_6\;and\;APS_5{\times}APS_2$ out of 15 crosses. Among the 15 reciprocal crosses studied, the combination $APS_8{\times}APS_{13}$ showed positive reciprocal effects for all the six traits. With both the parents $APS_5\;and\;APS_2$ being good general combiners the hybrid $APS_5{\times}APS_2$ showing high sca effects is recommended for commercial use.

• Korean Journal of Child Studies
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• v.8 no.1
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• pp.49-64
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• 1987

The purpose of this study was to investigate the effect of information of appearance, peer preference, and personality traits on children's attraction to unacquainted same sex peers, and to determine the relative importance of the three types of information for the selection of a friend. The subjects of this study were 160 (80 boys and 80 girls) second grade children in Seoul. A Preference Questionnaire was administered in Session I to determine the likes of each subjects. The modified Preference Questionnaire (Reaves, 1981) was used. The subjects were then randomly assigned to one of eight experimental conditions. In Session II, subjects were shown pictures of attractive and unacttractive children, described as having a positive or negative character, with preference similar Of dissimilar to their own. Then they were administered the Interpersonal Attraction Scale (Reaves, 1981). The data were analyzed by three-way ANOVA, $Scheff\acute{e}$ test, and $X^2$. The results of this study were as a follows: The physically attractive stimulus child was preferred to the physically unattractive stimulus child. The stimulus child with preferences similar to the subjects' was preferred to the stimulus with dissimilar preferences. The stimulus with positive personality traits was preferred to the stimulus ehild with a negative personality. A difference in order of importance among the variables with regard to their influence on attraction ratings was found. Personality had stronger influence on attraction ratings than appearance or preference.