• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.14 no.2
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• pp.229-237
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• 2003

Objectives：Among the studies related to excessive computer use, the studies for elementary school students are relatively rare. Because children have relatively poor ability to recognize and express themselves, the carers' information is important to assess the children. This study attempted to investigate the relationship between children's computer use and sociopsychiatric characteristics on the basis of carers' reports. Methods：The subjects of this study were 287 5th- and 6th-grade students in the elementary school in Seoul. The student carers were asked to answer the questions for children's computer use, the computer addiction test modified from Young's parent-child internet addiction test, Korean Personality Inventory for Children(K-PIC). SPSS(version 10) was used to analyse the differnece of computer use between genders and the relation of the computer addiction test with K-PIC. Results：1) The score of computer addiction test was significantly higher in male children than in female children and more male children compared to female children were distributed in the excessive user group. 2) The score of computer addiction test correlated with the scores of most clinical scales of K-PIC and the average scores of most clinical scale were significantly higher in the excessive user group than in the general user group. 3) More children with score above 65 in HPR, DLQ, FAM scale were distributed in excessive user group than in general user group. Conclusion：The 5th- and 6th-grade elementary school students with excessive computer use were found to show more sociopsychiatric problems. With these finding we suggest that social and clinical attention to the children who use computer excessively shoud be required.

• Korean Journal of Plant Tissue Culture
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• v.24 no.4
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• pp.239-256
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• 1997

Plants belonging to the category of 2n apomixis or agamospermy form embryos and seeds without the processes of normal meiosis and syngamy. Seeds produced in this way have identical genotype of their maternal parent. Three different types of agamospermy are recognized: diplospory, apospory, and adventitious (adventive) embryony. $F_1$ hybrid cultivars cannot be used as seed sources in the next ($F_2$) generation because this generation would be extremely variable as a result of genetic segregation. Hybrid vigor is also reduced in the $F_2$ generation. Therefore, parental stocks for hybrid seed production need to be maintained and cross must be continuously repeated. Agamospermic 2n apomixis would make it possible to fix the genotype of a superior variety so that clonal seeds faithfully representing that genotype could be continuously and cheaply produced independent of pollination. That is, $F_1$ hybrid seeds could be produced for many generations without loss of vigor or genotype alteration. Production of apomictic $F_1$ hybrid seed would be simplified because line isolation would not be necessary to produce seed or to maintain parental lines, and the use of male-sterile lines could be avoided. Overall, apomixis would enable a significant reduction in hybrid seed production costs. Additionally, the production of clonal seed is not only important for seed propagated crops, but also for the propagation of heterozygous fruit trees and timbers. Clonal seed would help avoid costly and time-consuming vegetative propagating methods that are currently used to ensure the large-scale production of these plants. Apomixis is scattered throughout the plant kingdom, but few important agricultural crops possess this trait Therefore, most research to date has centered on introgressing the trait of apomixis into agricultural crops such as wheat, maize, and some forage grasses from wild distant relatives by traditional cross breeding. The classical breeding approach, however is slow and often impeded by many breeding barriers. These problems could be surmounted by taking mutagenesis or molecular approach. Arabidopsis thaliana is a tiny sexually reproducing plant and is convenient in constructing and screening in molecular researches. Male-sterile mutants of Arabidopsis are particularly suitable genetic background for mutagenesis and screening for apomictic mutants. Molecular approaches towards isolating the genes controlling the apomictic process are feasible. Direct isolation of genes conferring apomixis development would greatly facilitate the transfer of this trait to wide variety of crops. Such studies are now in progress.

• The Journal of the Korea Contents Association
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• v.18 no.6
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• pp.467-480
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• 2018

The purpose of this study was to investigate gender difference of community-residing elderly's life satisfaction and influential factors. Data were collected from 461 elders aged 60+ with the cooperation of several social service center for the aged, senior centers, and senior citizen associations in Daejeon Metropolitan City and Chungcheongnam-do(Cheonan-si and Okcheon-gun). SPSS 22.0 software was used for t-test and cross tabulation analysis, correlation analysis, and hierarchical regression analysis. The results showed there was statistically significant difference of elderly's life satisfaction by gender in multivariate analysis including sociodemographic factors, social network and relationship with children variables, but no difference in bivariate analysis. There was also significant difference in the factors affecting community-residing elderly's life satisfaction by gender. A few factors like friend support, number of regular social gatherings, and subjective health status were statistically significant in predicting male elderly's life satisfaction. Predictors of female elderly's life satisfaction which were perceived elderly parent-children conflict, friend support, monthly income, subjective health status, support to children, support from children were more diverse, compared to the predictors for male elderly's life satisfaction. Based on the findings, suggestions for social welfare policy and practice to improve community-residing elderly's life satisfaction considering the gender difference were discussed.

• Journal of Elementary Mathematics Education in Korea
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• v.10 no.1
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• pp.89-106
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• 2006

The purposes of this study are to find out differences of the causes of mathematics anxiety in elementary school students according to the Grades and sex, and to find out which causes have more influence on achievement of mathematics and how much it is. For this purposes, the problems of this study are defined as follows: First, are there any differences in the influences of each super-causes and sub-causes of mathematics anxiety according to the Grades? Second, are there any differences in the influences of each super-causes and sub-causes of mathematics anxiety according to the sex? Third, what relation do the super-causes of mathematics anxiety have to the achievement of mathematics? The conclusions of this study are as follows: First, mathematics anxiety is much more affected by the internal cause like the cause of student attitude than the external cause like the causes of circumstance and the cause of teacher. Second. mathematics anxiety is much more affected by a direct experience like the causes of a shortage of time and the causes of student interest than indirect experience like the causes of teacher's authority and the causes of the application of daily life. Third, the causes of circumstance and parent's attitude. its sub-cause, have greater influence on the female group than on the male group. Fourth, in the middle Gradess, the female group is more affected by the cause of student attitude and the cause of circumstance than the male group, but in the higher Grades. the differences disappear and those two become common causes of anxiety. Fifth, As the students go up to the next Grades in school, the cause of teacher, the characteristic of the curriculum and the cause of prejudice have more influence on the mathematics anxiety. Sixth, the causes of teacher, the causes of mathematical curriculum and the causes of student attitude among super-causes of mathematics anxiety have a negative effect on the achievement of mathematics. But the causes of circumstance have a positive effect on it. And also, the causes of mathematical curriculum among super-causes is much related to the causes of teacher and the causes of circumstance.

• Phonetics and Speech Sciences
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• v.13 no.4
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• pp.75-87
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• 2021

The purpose of this study was to investigate, longitudinally, interruption behavior which children who do stutter (CWS), children who do not stutter (CWNS) and their mothers and relationship with disfluency of children showed during interactions with their mothers. Subjects for this study consisted of 2-5 year old CWS (male 2 and female 4), an age-matched group of CWNS (male 3 and female 3), and their mothers. Frequencies of normal disfluency (ND) and abnormal disfluency (AD) in children group and frequency of interruption and simultalk duration in children and mothers group were measured two times (initial visit and 12 months later) over the course of one year. As a result, no significant difference was observed in frequency of interruption and simultalk duration both between two mother groups and between two child groups at initial visit and 12 months later. However, frequency of interruption increased significantly over the course of one year in CWS group. A significant group difference was found in frequency of interruption of mothers but, no significant difference was observed in simultalk duration of mothers at initial visit. In the CWS·mothers group, no factors were related with disfluency of children at initial visit and 12 months later. These findings suggest that interruption is not just negative behavior, and that reducing interruption should be considered in child·parent interaction therapy for CWS.

• Korean Journal of Poultry Science
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• v.12 no.2
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• pp.89-95
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• 1985

Two experiments were undertaken to study the growth promoting effect of Spiramycin and Virginiamycin at the level of 5ppm each. In the first experiment, 180 day - old male broiler chickens (Maniker parent stock) were divided into 18 groups of 10 birds each. Six groups were placed on one of the three experimental diets (Nonmedicated control, Spiramycin supplemented diet and Virginiamycin supplemented diet). Basal diet of Experiment 1 contained 21.9% crude protein and 3159kcal /kg diet. Second experiment employed same treatments as were used in the Experiment 1. Ninety male and 90 female day-old broiler chickens(Maniker commercial) were grouped by 10 birds of sane sex in each and assigned to 3${\times}$2 factorial design. Basal diet of Experiment 2 contained 19.95% crude protein and 2931kcal/kg diet. Chicks were fed for six weeks in battery with raised floor and kept further for metabolic trials. The results of feeding trials showed that there were no statistically significant differences between treatments in weight gain, feed intake, feed efficiency and mortality. However, birds fed Antibiotic B supplemented diet grew approximately 3% more than the control in Experiment 1 and than those fed Antibiotic A supplemented diet in Experiment 2. Feed efficiency was also improved by supplementing Antibiotic B in both experiments. There were significant(P〈0.01) differences between sexes in growth rate, feed intake and feed efficiency. Birds fed Antibiotic B supplemented diet of Experiment 1 showed significantly (P〈0.01) greater availability for crude fat than those fed other diets. Birds fed Antiobiotic A supplemented diet in Experiment 1 showed significantly (P〈0.05) lower availability of crude fiber than those of other treatments. Weight of small intestine of birds fed Antibiotic B tended to be heavier than those fed other diets.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.7 no.1
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• pp.92-109
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• 1996

The objectives of the present study were to provide comprehensive assessment of the impact of epilepsy on the psychological well-being of children with epilepsy and to identify the neurological factors associated with the psychopathology. The participant patients were recruited from the population of children and adolescent aged 7 to 16 attending the OPD of department of pediatric neurology in Seoul National University Hospital in Korea. We exclude mental retardation, pervasive developmental disorder and brain organic pathology. As control group, formal students were chosen and their sex, age, achievement, socioeconomic status were matched to patients. The first author interviewed the children and their family members and obtained the developmental history and family information. We used the following 10 scales for assessing psychological and behavioral problems in patients and their family member. The scales were standardized and their validity and reliability were confirmed before. Parent rating scales : Yale children's inventory, Disruptive behavior disorder scale, Parent's attitude to epilepsy questionnaire, Family environment scale, Symptom check-list-90 revision, Children behavior check-list. Children's self rating scales : Children's depression inventory, Spielberger's state-trait anxiety anxiety, Piers-Harris self-concept inventory and Self-administered Dependency questionnaire for Mother. The result showed the risk factors associated depression were early onset, complex partial seizure, lateralized temporal focal abnormality on EEG, Drug polypharmacy, high seizure frequency and sick factors associated anxiety were old age of patient, lateralized temporal focal abnormality EEG, Drug polypharmacy, high seizure frequency. Also the result of this present study indicated that risk factors associated oppositional defiant disorder, conduct disorder and attention deficit hyperactivity disorder were young age, male, early onset, lateral temporal EEG abnormality and high seizure frequency. According to these results, common risk factors associated psychological and behavioral problems were lateralized EEG temporal abnormality, high seizure frequency in neurological factors.

• Journal of Korean Society of Forest Science
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• v.45 no.1
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• pp.1-10
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• 1979

This study was conducted to widen the range of characteristics of the hybrids, P.alba ${\times}$ P.glandulosa, i.e. aiming for gene population expansion P.glandulosa seemed to have the similar characteristics as the one segregated from the natural hybrids between P.alba and P.davidiana. Thus the main objectives of this study were to make many crosses among poplars and then to identify leaf characteristics of the crosses similar to P.glandulosa, the results obtained can be summerized as follows; 1. Leaf characteristics such as leaf margin, presence of glands at leaf base and pubescence density, of crosses made from P.alba.davidiana ${\times}$ P.datidiana, and P.davidiana.alba ${\times}$ P.davidina showed 44% and 90%, respectively, of similarity to P.glandulosa. 2. The ratio of leaf size, including leaf length, leaf width, length from leaf base to width line, and petiole length, of the above crosses was similar to P.glandulosa. 3. Pubescence density of the dorsal leaf surface in hybrids between P.alba and P.davidiana showed generally intermediate of the parental appearance. Frequency of pubescence appearance differed from depending upon the use of P.alba, either as a female or a male parent. The use of P.alba as a male parent increased frequency of Pubescence appearance. 4. The presence of glands at the leaf base in P.glandulosa may be inherited from P.davidiana which possesses gland although gland is not present in all P.davidiana rather from P.alba which has no gland.

• Horticultural Science & Technology
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• v.31 no.4
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• pp.473-482
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• 2013

Molecular markers, as an efficient selection tool, have been and is being used for practical breeding program in chili pepper (Capsicum annuum L.). Recently, a lot of researches on inheritance and genetic analysis for quantitative traits including capsaicinoids, carotenoids, and sugar content in pepper are being performed worldwide. It has been also reported that QTL mapping is a necessary tool to develop molecular markers associated with the quantitative traits. In this study, we suggested a new method to construct a pepper genetic map using SNP (HRM) markers generated from NGS resequencing of female and male parents. Plant materials were C. annuum 'NB1' (female parent), C. chinense 'Jolokia' (male parent), and their $F_2$ population consisting of 94 progenies. Sequences of 4.6 Gbp and 6.2 Gbp were obtained from NGS resequencing of 'NB1' and 'Jolokia', respectively. Totally, 4.29 million SNPs between 'NB1' and 'Jolokia' were detected and the 1.76 million SNPs were clearly identified. Among them, total 145 SNP (HRM) primer pairs covering pepper genetic map were selected, and the 116 SNP (HRM) markers of them were located on this map. Total distance of the map, which consisted of 12 linkage groups and matched with basic chromosome numbers of pepper, was 1,167.9 cM. According to the mapping result, we concluded that our mapping method was suitable to construct a pepper genetic map fast and accurately. In addition, the genetic map could be directly used for QTL analysis of traits different between both parents.

• Journal of Yeungnam Medical Science
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• v.12 no.1
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• pp.56-74
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• 1995

The authors applied ADDES-HV parent evaluation scale for the purpose of screening test to 538 2nd grade elementary school students from March 1994 to May. The results were as follows: There was no differences in scores of ADHD between schools. In comparing the male and female between three school students, male students showed signifieant high scores (p<0.05) than female students in the score of ADDES-HV subscale and total. There was no significant differences in ADDES-HV scale between male students and female students in both ADHD patients and normal controls. In reliability test for test and retest, the reliability coefficient was higher satisfatorily and that of inattention was 0.80, inpulsivity was 0.69, hyperactivity was 0.63 and the total score was 0.82. In reliability test by internal consistancy, the Cronbach ${\alpha}$ coefficient of patient group was 0.85(p<0.05) and that of normal control was 0.84(p<0.05). The Concurrent validity between ADDES-HV scale and DSM-III-R scale was 0.57(p<0.05) in ADHD patient group and 0.84(p<0.05) in normal control group. In discriminant validity test between ADHD patient group and normal control, the ADHD patient group showed higher score(p<0.05). The total disciminant capacity of the patient group in ADDES-HV scale was 94.44%. When we regard the cut off point as standard deviation 1.5, the male student was 80 score and the female student was 69 score. In this point of view, ADDES-HV scale was proved to be the useful screening test tool for ADHD research and showed higher reliability and validity in applying to Korean subjects.