• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.304-311
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• 2010

Korea National Forest Inventory System has been adopting different cluster plot design and new equations to estimate growing stock volumes since 2006. These changes have resulted in volume estimations which show some difference from previous ones. This study is to find out the source of such difference. For this, relevant data was collected from 80 plots of 20 cluster samples according to the cluster plot design applied to 4th and 5th National Forest Inventory. Then growing stock volumes were estimated by using current and previous individual tree volume equations respectively. An investigation was made to detect whether such difference in volume estimates was originated from the changes in cluster plot design or from using different volume equations. T-test results showed that the difference from changes in cluster plot design was negligible. Instead, changes in volume equations had statistically significant effects in volume estimation. Since the volume estimation by the 5th National Forest Inventory would bring overestimation by applying different volume equations, all the volume estimations made prior to 2006 would require necessary modifications for international reporting.

• Journal of agricultural medicine and community health
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• v.36 no.1
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• pp.25-35
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• 2011

Objectives: This study aimed to compare depression and social support according to general characteristics and to investigate the influence of social support on depression. Methods: This study analyzed raw data from a project funded by Jeju Province. Data were collected through home visit interview with 750 households selected by using a randomized cluster sampling method. CES-D was used to measure depression, and the Medical Outcomes Study Social Support Survey was used to measure social support. The data of 1,155 subjects were analyzed using t-test, ANOVA, and regression. Results: The mean was 11.35 for depression and 75.53 for social support. Women showed a higher depression score and a lower social support score than men did. Older people; the divorced or the bereaved; and those in groups comprising people with lower education, lower social class, poor health, or high stress presented higher depression and lower social support. The result of stepwise regression showed that social support was one of the predictive variables of depression, and 22% of variance was explained by social support in this study. Conclusions: Social support was a powerful predictive variable of depression, and it was suggested that to prevent and manage depression, strategies that enhance social support should be developed and evaluated.

• Journal of Digital Convergence
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• v.16 no.10
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• pp.537-544
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• 2018

The purpose of this study is to identify the impact of well-being-oriented activities of university students in liberal arts and physical education classes on happiness. First, among well-being-oriented activities, females are more likely to have eco-friendly behavior, well-being-oriented, hobby-orientation and exercise orientation, and males are more likely to be better at purchasing well-being products and mental health. Happiness was found to be higher in boys than in outer happiness, self-controlled happiness, and inner happiness. By grade, there was no difference between men and women in well-being activities, and the happiness showed that the second and third grades were higher than the first grade, while the second and third grade were higher in inner happiness. The happiness level showed that the number of students who attended three sessions showed higher level of happiness. Second, among the well-being activities of students in liberal physical education classes, external happiness shows in hobby-orientation, mental health and exercise orientation. Self-regulating shows in well-being meal, hobby orientation, mental health. Inner happiness shows in well-being meal, hobby orientation, mental orientation and exercise orientation.

• Journal of Digital Convergence
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• v.18 no.9
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• pp.277-283
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• 2020

The purpose of this study was to identify the risk factors influencing stroke. The research method was used two-stage stratified cluster sampling using data from the National Health and Nutrition Survey (2016-2018). This study subjects performed a complex sample logistic regression analysis on adults aged 19 or older. Risk factors affecting stroke were shown as follows: in age groups, odds ratio were conformed when people are in their 70s, the rate is 8.861 times higher; when they are in their subjective health conditions, the odds ratio are 4.501 times higher in the bad groups; odds ratio was 3.158 times higher in the group diagnosed with hypertension and 1.598 times higher in the group diagnosed with diabetes. The result of this study found that chronic diseases such as high blood pressure and diabetes and the management of senior citizens are important because stroke is dangerous and can be managed through prevention.

• Journal of the Korean Data and Information Science Society
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• v.24 no.4
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• pp.815-824
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• 2013

Traditional Pearson chi-squared test is not appropriate for the data collected by the complex sample design. When one uses the traditional Pearson chi-squared test to the complex sample categorical data, it may give wrong test results, and the error may occur not only due to the biased variance estimators but also due to the biased point estimators of cell proportions. In this study, the design based consistent Wald test statistics was derived for k-population homogeneity test, and the traditional Pearson chi-squared test statistics was partitioned into three parts according to the causes of error; the error due to the bias of variance estimator, the error due to the bias of cell proportion estimator, and the unseparated error due to the both bias of variance estimator and bias of cell proportion estimator. An analysis was conducted for empirical results of the relative size of each error component to the Pearson chi-squared test statistics. The second year data from the fourth Korean national health and nutrition examination survey (KNHANES, IV-2) was used for the analysis. The empirical results show that the relative size of error from the bias of variance estimator was relatively larger than the size of error from the bias of cell proportion estimator, but its degrees were different variable by variable.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.501-507
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• 2020

The purpose of this study is to identify the personal characteristics of college students participating in leisure activities and the impact of their leisure experience on job-seeking Stress, To achieve this purpose, subjects of this study were sampled 264 university students participant using purposeful sampling method for 2 months from september to october of 2019. Using questionnaires stratified cluster random sampling in university students in C city. Studies have shown that first, looking at gender, women receive more academic stress than men. Second, looking at the results of the school year, the first and fourth graders received more personality stress than the second and third graders. Third, if you look at the results of the major category, it turns out that students in the natural major receive more personality stress than in the social major category. In addition, students in the humanities major are more stressed out about the Family environment stress than in the natural major. Fourth, if you look at the results of the allowance, students who receive 400,000 won to 500,000 won and those who receive 100,000 won to 200,000 won or less are under stress from the family environment stress than those who receive 500,000 won or more. Fifth, if you look at the results of your experience in leisure activities, the more experience you have in leisure Therefore, college students will have to lay the groundwork for self-control through various leisure activities for job stress. activities, the lower your job-seeking Stress.

• Journal of agricultural medicine and community health
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• v.38 no.1
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• pp.25-38
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• 2013

Objectives: The aim of this study is to analyze the utilization behaviour and influencing factors of complementary and alternative medicine (CAM) therapies among elderly people with chronic diseases. Methods: The study population was selected among 9 welfare facilities for the aged in 2 cities among Daegu Metropolitan City & Gyeongsangnam Province by two-stage cluster sampling. 250 senior citizens participated in a face-to-face interview using a structured questionnaire. Logistic regression analysis was performed to examine the association between the utilization of CAM therapies and various characteristics of the elderly. All statistics were analyzed using the PASW (ver 18.0). Results: Among 233 elderly peoples, 70.4% (164 persons) had used various kinds of CAM therapies (including nutritional methods, pharmacologic and biologic treatments, etc.) more than once during the last year. 48.8% (64 persons) ~ 60.7% (88 persons) of the elderly used CAM therapies without health and medical experts' counsel. The elderly with perceptions of CAM therapy used it 2 times more than those without knowledge of CAM therapies. The number of chronic diseases was more likely to increase the usage of nutritional methods (OR=2.92, 95% CI: 1.07-7.97), manipulative and body-based practices (OR=5.85, 95% CI: 1.97-17.34), pharmacologic and biologic treatments (OR=2.92, 95% CI: 1.49-8.17). Elderly with diabetes used nutritional methods 3.76 (95% CI: 1.49-9.47) more than elderly without diabetes. Conclusions: CAM therapies use in the aged with chronic diseases appears common. The findings suggest that the clinical efficacy and safety of CAM therapies on medical management of chronic disease may be investigated and that patient-physician communication need to be strengthened.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.690-695
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• 2003

Physiological activities of 40% ethanol extracts of Phellinus ribis were studied by employing several biological and biochemical assays. The extracts of Phellinus ribis displayed nitrate-scavenging activities (NSA) at pH 1.2 as with 64% NSA with 1.0 mg/mL of the extracts. They also had 91% 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activities at the concentration of 1.0 mg/mL. Antioxidant activities of the extracts (at 0.5 mg/mL) on the autoxidation of linoleic acid (p<0.001) were also observed.. The inhibitory effect of the extracts on angiotensin converting enzyme was 11%. Cytotoxic effects of Phellinus ribis extracts against human cancer cell tines were also examined using MTT assay. The extracts (at 50 mg/mL) had severe growth inhibitory effects on A549, Hela, AGS, and SK-Hep-1, which were 8, 44, 76 and 42%, respectively. Ames test indicated that the extracts had no mutating effects on Salmonella typhimurium TA98 and TA100.

• Journal of Life Science
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• v.16 no.7 s.80
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• pp.1112-1118
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• 2006

Bordetella bronchiseptica, the agent of swine atrophic rhinitis and kennel cough in dogs, is a mucosal pathogen and produces the hydroxamate type alcaligin siderophore under iron-limited conditions. Genes involved in alcaligin siderophore biosynthesis are contained in an alcABCDE operon. In order to provide direct evidence for the role of AlcA in alcaligin biosynthesis, we needed a B. bronchiseptica mutant carrying alcA gene deletion. A 0.6 kb alcA 5'-flanking and 0.7kb 3'-flanking DNA fragments were PCR amplified with the use of pCP1.11 as a template DNA. The 5'-and 3'-flanking DNA fragments were joined in a suicide plasmid, resulting in a recombinant suicide plasmid pDM1. After introduction of pDM1 into B. bronchiseptica by conjugation, the allelic exchange technique was performed and a B. bronchiseptica alcA deletion mutant, named B. bronchiseptica H1, was obtained. The mutant strain produced reduced amount of siderophore as expected. When a plasmid containing complete alcA gene was transformed back into the mutant, the complemented mutant recovered ability of siderophore production. These results indicated that AlcA is one of essential components for the alcaligin siderophore biosynthesis. The mutant strains obtained in this study will be used in the further studies for the biochemical function of AlcA.

• Korean Journal of Microbiology
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• v.44 no.4
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• pp.352-357
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• 2008

We evaluated cultivation methods to obtain pure cultures of previously uncultivated bacteria from soil. Soil bacteria (suspensions) were inoculated onto various oligotrophic media with one of the following additives: 1) soil extract; 2) anthraquinone disulfonate (humic acid analogue); 3) acyl homoserine lactones (quorum-signaling compounds); 4) catalase (for the protection of bacteria from exogenous peroxides). After the relatively long period (60 days) of incubation with elevated concentrations of $CO_2$ (5%, v/v), the media containing catalase showed the highest colony count. We purified 147 randomly selected colonies from the media and the isolates were subjected to the phylogenetic analyses of their 16S rRNA gene sequences. Phylogenetic analysis revealed that approximately 30% of the isolates might belong to novel species or novel family, suggesting that the media and incubation conditions used could be useful for the cultivation of as-yet-uncultured bacteria. Especially, bacteria belonging to the phylum Acidobacteria, ubiquitous bacterial taxon known as an uncultured bacterial group (at least difficult to culture from environmental samples), were successfully cultured in this study.