• Journal of Ecology and Environment
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• v.40 no.1
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• pp.5-11
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• 2016

Background: As the decomposition of lignocellulosic compounds is a rate-limiting stage in the nutrient mineralization from organic matters, elucidation of the changes in soil enzyme activity can provide insight into the nutrient dynamics and ecosystem functioning. The current study aimed to assess the effect of thinning intensities on soil conditions. Un-thinned control, 20 % thinning, and 30 % thinning treatments were applied to a Larix kaempferi forest, and total carbon and nitrogen, total carbon to total nitrogen ratio, extractable nutrients (inorganic nitrogen, phosphorus, calcium, magnesium, potassium), and enzyme activities (acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, ${\beta}$-glucosaminidase) were investigated. Results: Total carbon and nitrogen concentrations were significantly increased in the 30 % thinning treatment, whereas both the 20 and 30 % thinning treatments did not change total carbon to total nitrogen ratio. Inorganic nitrogen and extractable calcium and magnesium concentrations were significantly increased in the 20 % thinning treatment; however, no significant changes were found for extractable phosphorus and potassium concentrations either in the 20 or the 30 % thinning treatment. However, the applied thinning intensities had no significant influences on acid phosphatase, ${\beta}$-glucosidase, ${\beta}$-xylosidase, and ${\beta}$-glucosaminidase activities. Conclusions: These results indicated that thinning can elevate soil organic matter quantity and nutrient availability, and different thinning intensities may affect extractable soil nutrients inconsistently. The results also demonstrated that such inconsistent patterns in extractable nutrient concentrations after thinning might not be fully explained by the shifts in the enzyme-mediated nutrient mineralization.

• Herbal Formula Science
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• v.10 no.1
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• pp.73-80
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• 2002

We have examined the purgative effect of three Jechun-jun formulas in sprague dawley(SD) rat. Three jechun-jun formulas were Jechun-jun(Sample I ) and augmented Jechun-jun(Sample II) and augmented Jechun-jun add rhubarb(sample III ). We examined the amount and the humidity of feces in rat. The experimental animals were devided into four groups. as control group and three Jechun-jun (sample I, II, III). We administerd the water extract of sample I, II, III to rat per oral for 8days long. After every 24hours measured the amount of wet feces from rats in metabolic cage. Humidity rate of feces from rat was at first measure wet feces for 24hours (W) and measure dried feces (W1) and then we consider W-W1 as humidity. High humidity rate means constipation changes into moistening stool. The amount of wet feces and humidity rate of feces in rats were increased in sample I, II, III. Sample I has highest humidity rate of feces. so showed strong moistening effect. Sample II has mild effect in treating constipation. sample III has most amount of wet feces. in conclusion Jechun-jun has an effect of moistening stool. and augmented Jechun-jun add rhubarb has strong purgative effect.

• Biomolecules & Therapeutics
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• v.15 no.2
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• pp.95-101
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• 2007

Resveratrol (3,5,4’-trihydroxy-trans-stilbene), a naturally occurring phytoallexin abundant in grapes and several plants, has been shown to be active in inhibiting proliferation and inducing apoptosis in several human cancer cell lines. On the line of the biological activity of resveratrol, a variety of resveratrol analogs were synthesized and evaluated for their growth inhibitory effects against several human cancer cell lines. In the present study, we found that one of the resveratrol analogs, 3,4,5-trimethoxy-4’-bromo-cis-stilbene, markedly suppressed human colon cancer cell proliferation (EC$_{50}$ = 0.01 ${\mu}$g/ml), and the inhibitory activity was superior to its corresponding trans-isomer (EC$_{50}$ = 1.6 ${\mu}$g/ml) and resveratrol (EC$_{50}$ = 18.7 ${\mu}$g/ml). Prompted by the strong growth inhibitory activity in cultured human colon cancer cells (Col2), we investigated its mechanism of action. 3,4,5-Trimethoxy-4’-bromo-cis-stilbene induced arrest of cell cycle progression at G2/M phase and increased at sub-G1 phase DNA contents of the cell cycle in a time- and dose-dependent manner. Colony formation was also inhibited in a dose-dependent manner, indicating the inhibitory activity of the compound on cell proliferation. Moreover, the morphological changes and condensation of the cellular DNA by the treatment of the compound were well correlated with the induction of apoptosis. These data suggest the potential of 3,4,5-trimethoxy-4’-bromo-cis-stilbene might serve as a cancer chemotherapeutic or chemopreventive agent by virtue of arresting the cell cycle and inducing apoptosis for the human colon cancer cells.

• Safety and Health at Work
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• v.2 no.1
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• pp.70-82
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• 2011

Objectives: Ischemic heart disease (IHD) is a major cause of death in Korea and known to result from several occupational factors. This study attempted to estimate the current magnitude of IHD mortality due to occupational factors in Korea. Methods: After selecting occupational risk factors by literature investigation, we calculated attributable fractions (AFs) from relative risks and exposure data for each factor. Relative risks were estimated using meta-analysis based on published research. Exposure data were collected from the 2006 Survey of Korean Working Conditions. Finally, we estimated 2006 occupation-related IHD mortality. Results: For the factors considered, we estimated the following relative risks: noise 1.06, environmental tobacco smoke 1.19 (men) and 1.22 (women), shift work 1.12, and low job control 1.15 (men) and 1.08 (women). Combined AFs of those factors in the IHD were estimated at 9.29% (0.3-18.51%) in men and 5.78% (-7.05-19.15%) in women. Based on these fractions, Korea's 2006 death toll from occupational IHD between the age of 15 and 69 was calculated at 353 in men (total 3,804) and 72 in women (total 1,246). Conclusion: We estimated occupational IHD mortality of Korea with updated data and more relevant evidence. Despite the efforts to obtain reliable estimates, there were many assumptions and limitations that must be overcome. Future research based on more precise design and reliable evidence is required for more accurate estimates.

• Journal of Periodontal and Implant Science
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• v.42 no.4
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• pp.136-143
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• 2012

Purpose: The osseointegration around titanium mini-implants installed in macroporous biphasic calcium phosphate (MBCP) blocks was evaluated after incubation with recombinant human bone morphogenetic protein-2 (rhBMP-2) in an ectopic subcutaneous rat model. Methods: Mini-implants (${\varphi}1.8{\times}12$ mm) were installed in MBCP blocks (bMBCPs, $4{\times}5{\times}15$ mm) loaded with rhBMP-2 at 0.1 mg/mL, and then implanted for 8 weeks into subcutaneous pockets of male Sprague-Dawley rats (n=10). A histomorphometric analysis was performed, and the bone-to-implant contact (BIC) and bone density were evaluated. Results: Significant osteoinductive activity was induced in the rhBMP-2/bMBCP group. The percentage of BIC was $41.23{\pm}4.13%$ (mean${\pm}$standard deviation), while bone density was $33.47{\pm}5.73%$. In contrast, no bone formation was observed in the bMBCP only group. Conclusions: This model represents a more standardized tool for analyzing osseointegration and bone healing along the implant surface and in bMBCPs that excludes various healing factors derived from selected animals and defect models.

• Research in Community and Public Health Nursing
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• v.16 no.2
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• pp.115-126
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• 2005

Purpose: The aims of this study were to describe general characteristics and needs of home health care, and to find the differences between home health care needers and non-needers. Method: In this study, 642 subjects participated who lived in Muan, Jollanam-do. Data were collected in August 2001 using a self-reported questionnaire. The questionnaire was a revised and simplified form of the Organization of Community Health System Program at the Seoul National University. Collected data were analyzed through Kruskal-Wallis test. t-test. and Chi-squire for cross-sectional analysis. Result: The average age of the subjects was 52.6 years and 33.3% of them aged over 65 years. Twenty six percent of them had chronic degenerative diseases. The percentages of hypertension patients and D.M. patients were 6.4% and 2.5%, respectively. The number of family members was 2.95 on the average, 2.19 in cases of families with the elderly and 3.33 in cases of families without the elderly. The rate of disability of the elderly was 10.5%. Marital status (p=.000), the number of family members (p=.000), education (p=.000), job (p=.000) and health insurance (p=.027) were significantly different between home care needers and non-needers. Home care needers had less living expenses (p=.001), more frequent hospital admissions (p=.004), higher chronic disease rate (p=.000) and more frequent visits to public health center (p=.027) than non-needers. Home care needers who wanted free service were twice as many as non-needers. Conclusion: Home care need was very high in rural areas and the needers had worse characteristics (low educational level. low income, no job and no family). Therefore, it is necessary to develop cheaper and more accessible services for home care needers in rural areas.

• Journal of the Korean Geosynthetics Society
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• v.15 no.1
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• pp.1-10
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• 2016

Recently, offshore wind farms are increasingly expected, because there are huge resource and large site in offshore. Jeju island has optimum condition for constructing a wind energy farm. Unlike the mainland, Jeju island has stratified structure distribution between rock layers sediments due to volcanic activation. In these case, it can be occur engineering problems in whole structures as well as the safety of foundation as the thickness and distribution of sediment under top rock layer can not support sufficiently the structure. In this study, field lateral load test of the pile for analyzing lateral behavior of the offshore wind turbine which is embedded in basalt. After calculating the subgrade resistance and the horizontal deflection from the measured strain to derive p-y curve from the lateral load test results, the subgrade resistance amplifies the error in the process of differentiation and the error of piecewise polynomial curve fitting is the smallest. In order to calculate the horizontal deflection from the measured strain, the six-order polynomial was used.

• Journal of Agricultural Extension & Community Development
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• v.8 no.1
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• pp.15-23
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• 2001

As Internet and World Wide Web become more popular in our society, the interests in effective application to the field of rural development and agricultural extension service are increasing. The potential in Web-based agricultural extension service is expressed in many areas, such as agriculture information, Web-based training and education, and virtual rural community for rural development and agricultural extension service. The research on the Web and its related issues has been conducted in many ways, but the interests in the competencies and skills of staff who are in charge of Web developing and managing have not been exposed yet. The purpose of this study was to investigate the important competencies and skills for Web developing and managing for enhancing the effectiveness of rural development and agricultural extension service. Twelve extension service staff and on staff in the extension service support center were interviewed. The results of study showed that there were eight essential competencies; competencies to understand rural community and agricultural extension service, to understand the farmers as Web users, to design and develop effective Web sites, to understand the nature of hypertext, to utilize instruction theories, to absorb new technology, to manage projects, and to utilize external sources. The results of study also showed that there was lack of support systems for Web development and information. Overall, the findings of this study suggest that establishing long-term education and training system for technology, electronic performance support systems, and cooperation with universities and colleges for technology are of particular importance for promoting Web-based extension services.

• Health Policy and Management
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• v.18 no.4
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• pp.125-147
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• 2008

The purpose of this study is to propose the factors affecting collaboration between community nurses and social workers in Korea. Data that is used in this study, were collected from 295 provider respondents by questionnaire, additionally from telephone survey and secondary data review. This study focuses on the working relationship between professionals in the field of health and social care. Based on the literature review, this study proposes a conceptual framework for collaboration between nurses and social workers in community health and social care. The dependent variable in this study is collaboration. It reveals whether or not the inter-professional works and shows the level of collaboration. The independent variables are categorized in: the client characteristics (frailty of client, client-provider relationship); the provider characteristics (specialization, perception of interdependence, perception of the other professional); the organization characteristics (closeness of the other professional, autonomy, on-the-job training, evaluation-reward); and the community characteristics (urbanization, capacity of resources). Major findings are as follows: First, the factors that appear to have the strongest impact on whether or not inter-professional working of respondent sampled are: the perception of other professional; the perception of interdependence; closeness of, the, other professional; and the frailty of client. Secondly, the factors that found to have the most significant effect on level of cooperation are: the perception of, the other professional; on-the-job training; evaluation-reward; and the closeness of the other professional.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.1
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• pp.39-45
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• 1999

Refining in papermaking plays an important role in changing fiber properties as well as paper properties. The major effects of refining on pulp fibers are internal and external fibrillation, fiber shortening, and fines formation. Many workers showed that internal fibrillation of the primary refining effects was most influential in improving paper properties. In particular, refining produces separation of fiber walls into several lamellae, thus causing fiber wall swelling with water penetration. This leads to the increase of fiber flexibility and of fiber-to-fiber contact during drying. If the fibers are very flexible, they will be drawn into close contact with each other by the force of surface tension as the water is removed during the drainage process and drying stages. In order to study the effect of fiber wall delamination on paper properties, cross-sectional image of fibers in a natural condition had to be generated without distortion. Finally, it was well recognized that confocal laser scanning microscope (CLSM) could be one of the most efficient tool for creating and quantifying fiber wall delamination in combination with image analysis technique. In this study, the CLSM could be used not only to observe morphological features of transverse views of swollen fibers refined under low and high intensity, but also to investigate the sequence of fiber wall delamination and fiber wall breakage. From the CLSM images, increasing the specific energy or refining decreased the degree of fiber collapse, fiber cross-sectional area, fiber wall thickness and lumen area. High intensity refining produced more external fibrillation.