• Food Science of Animal Resources
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• v.31 no.4
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• pp.551-556
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• 2011

The objective of this study was to determine the resistance of Cronobacter sakazakii in acidic environments. The D-values of CAFM2 (ATCC 29544), EB 1, EB 5, and EB 41 at pH 2.5 in TSB were significantly (p<0.05) higher when cells were adapted at pH 4.5 in TSB for 5-h then when cells were not adapted at pH 4.5 in TSB. The D-values of CAFM2, EB1, and EB 41 at pH 2.5 in TSB were significantly (p<0.05) higher when cells were adapted at pH 4.5 in TSB for 10-h then when cells were not adapted at pH 4.5 in TSB. The D-values of CAFM2 and EB1 at pH 2.5 in TSB were significantly (p<0.05) higher when cells were adapted at pH 4.5 in TSB for 24-h then when cells were not adapted at pH 4.5 in TSB. The adaptation of C. sakazakii to mild acidic environments may result in increased resistance to severe acidic environments. The D-values of all test strains at pH 2.5 in TSB were significantly (p<0.05) higher when cells were cultured at pH 4.5 then when they were cultured at pH 7.2 in TSB. These data indicate that cells cultured in mildly acidic environments may result in increased resistance to severe acidic environments. The acid adaptation of C. sakazakii showed an increased resistance to acidic environments. The acid adaptation response of C. sakazakii has important implications for food safety, which should be considered when food preservation measures are developed.

• The Korean Journal of Pesticide Science
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• v.15 no.3
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• pp.231-237
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• 2011

Highly bio-active plant essential extracts and oils from pepper, clove bud, rosemary and origanum which are selected to develop environment-friendly insecticides was studied for their acute toxicity. The results of acute oral toxicity using rats showed $LD_{50}$ value of over 2,000 mg/kg bw for pepper, clove bud, rosemary and origanum oils. The calculated acute dermal $LD_{50}$ value of pepper was over 4,000 mg/kg bw and anther testing materials was over 4,000 mg/kg bw. The skin irritation test showed that pepper, clove bud and rosemary oils had no irritation while origanum oil had a moderate irritation. According to the eye irritation test, it showed that there was no irritation for pepper and rosemary oils, while there were irritation for clove bud and origanum oils. Consequently, pepper and rosemary oils were shown to be low in toxicity whereas clove bud oil was indicated to cause a mild eye irritability and origanum oil, causing a moderate skin and eye irritability.

• Journal of Wetlands Research
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• v.16 no.3
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• pp.327-336
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• 2014

Submerged thin walls are extreme case of submerged rectangular blocks, and could be used for many purposes in rivers or coastal zones, e.g. to tsunami. To understand flow characteristics including flow and pressure fields around a specific submerged thin wall a numerical model was applied which includes computation of hydrodynamic pressure on ${\sigma}$-coordinate. ${\sigma}$-coordinate has strong merits for simulation of subcritical flow over mild-sloped beds. On the other hand ${\sigma}$-coordinate is quite poor to treat sharp structures on the bed. There have been a few trials to incorporate dynamic pressure in ${\sigma}$-coordinate by some researchers. One of the previous approaches includes process of sloving the Poisson equation. However, the above method includes many high-order terms, and requires long cpu for simulation. Another method SOLA was developed by Hirt et al. for computation of dynamic pressure, but it was valid for straight grid system only. Previous SOLA was modified for ${\sigma}$-coordinate for the present purpose and was adopted in a model system, CST3D. Computed flow field shows reasonable behaviour including vorticity is much stronger than the upstream and downstream of the structure. The model was verified to laboratory experiments at a 2DV flume. Time-average flow vectors were measured by using one-dimensional electro-magnetic velocimeter. Computed flow field agrees well with the measured flow field within 10 % error from the speed point of view at 5 profiles. It is thought that the modified SOLA scheme is useful for ${\sigma}$-coordinate system.

• Journal of Korean Academy of Nursing
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• v.11 no.1
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• pp.45-63
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• 1981

This study was done to determine the relationship between the anxiety levels of hospitalized psychiatric patients and various influencing variables. The purpose of this study was to determine factors that may help hospitalized psychiatric patients to experience lower levels of anxiety in relation to changing situations and provide the basic data for a dynamic approach which is important in the field of modern psychiatric nursing that understands and analyses the meaning of patients behavior. The anxiety may produce stress, which is a common experience among all human beings. Patients may merely feel uncomfortable in the state of mild anxiety, however, the severe state could be an obstacle to treatment and recovery from disease. The anxiety of the psychiatric patient is a factor which greatly influencing the patient's behavior, so his disorderd behavior is an expression of defence or pathologically fixed behavior. According the psychiatric patient's anxiety at the time of admission is the concern of the health team. The nurse's special concern has to do with understanding and supporting the patient and meeting his individual needs by frequent close contact during the entire hospitalization period, compared to other teamembers the nurse's responsibility in this regard is greated. So this study emphasizes the necessity of creating conditions these, but above all the psychiatric nurse should create a therapeutic environment by not only regarding the patient's behavior or symptoms but understanding the meaning of them. The subjects of this study were 57 psychiatric patients selected from the K neuropsychiatric hospital located in Kunsan city. Data were collected twice from the same patients within a 24 hour period after admission and 10 days after admission. (September 18th to November 8th, 1980). The data collected method was through direct interview, and the interview time was 20 minutes for each patient. Data analysis included Item Analysis & Internal Consistency Reliability Tests, Percentages, t-test, analysis of variance and stepwise multiple regression analysis. The findings of this study were as follows. A. Test of Hypothesis a. Hypothesis 1 :“The anxiety level of psychiatric patients within 24 hours after admission will be higher than those of the same patients 10 days after admission,”was accepted. (t = 3. 15 ; p < 0.005) b. Hypothesi 2:“The more the number of admissions the higher the level of anxiety related to two categories”, was accepted. (affective anxiety: F = 5.50, p < 0.005, Somatic anxiety: F = 9.12, p <.

• Journal of Periodontal and Implant Science
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• v.32 no.1
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• pp.129-142
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• 2002

Epithelial-mesenchymal interaction plays a important role in cell growth and differentiation. This interaction is already well known to have an importance during the organ development as well as cell growth and differentiation. However, in vitro experimental model is not well developed to reproduce in vivo cellular microenvironment which provide a epithelial-mesenchymal interaction. Because conventional monolayer culture lacks epithelial-mensenchymal interaction, cultivated cells have an morphologic, biochemical, and functional characteristics differ from in vivo tissue. Moreover, it's condition is not able to induce cellular differention due to submerged culture condition. Therefore, the aims of this study were to develop and evaualte the in vitro experimental model that maintains epithelial-mesenchymal interaction by organotypic raft culture, and to characterize biologic properties of three-dimensionally reconstituted oral keratinocytes by histological and immunohistochemical analysis. The results were as follow; 1. Gingival keratinocytes reconstituted by three-dimensional organotypic culture revealed similar morphologic characteristics to biopsied patient specimen showing stratification, hyperkeratinosis, matutation of epithelial architecture. 2. Connective tissue structure was matured, and there is no difference during stratification period of epithelial 3-dimensional culture. 3. The longer of air-exposure culture on three-dimensionally reconstituted cells, the more epithelial maturation, increased epithelial thickness and surface keratinization 4. In reconstitued mucosa, the whole epidermis was positively stained by anti-involucrin antibody, and there is no difference according to air-exposured culture period. 5. The Hsp was expressed in the epithelial layer of three-dimensionally cultured cells, especially basal layer of epidermis. The change of Hsp expression was not significant by culture stratification. 6. Connexin 43, marker of cell-cell communication was revealed mild immunodeposition in reconstitued epithelium, and there is no significant expression change during stratification. These results suggest that three-dimensional oragnotypic co-culture of normal gingival keratinocytes with dermal equivalent consisting type I collagen and gingival fibroblasts results in similar morphologic and immunohistochemical characteristics to in vivo patient specimens. And this culture system seems to provide adequate micro-environment for in vitro tissue reconstitution. Therefore, further study will be focused to study of in vitro gingivitis model, development of novel perioodntal disease therapeutics and epithelial-mensenchymal interaction.

• Korean Journal of Social Welfare
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• v.58 no.3
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• pp.313-340
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• 2006

The purpose of this study was to examine predictors of move intention to silver town in Jeju Island. Participants were 449 middle age and elderly who live in Seoul, Gyungido, Inchun Metropolitan and Jeju island. Participants were completed a questionnaire and/or structured interview that included measures of socioeconomic variables, motivation to move, determinants of move selection, conditions of location, and preparation for old age. Results of descriptive analysis revealed that cognition level of sliver industry and silver town was relatively high and medical service was the best necessary field, followed by field of leisure activity, house, life and finance. Logistic regression analyses on the effects of socioeconomic variables on move intention indicated that region, occupation and house ownership had significant effects on move intention to silver town. Result of motivational effect on move intention revealed that solution of offspring's burden was the most important factor, followed by convenient life of the aged, enjoyment of freedom for the elderly life. Result on the influence of determinants of move selection indicated that medical service facilities, resort facilities and leisure, cultural service facilities had significant effect on move intention. Among conditions of location for Jeju island, mild climate, comfort environment and low-price were significant predictors on move intention. Overall, result on relative influence of individual factors indicated that low price factor was the most important predictor, followed by resort facilities, cognition on necessity of silver town, enjoyment of freedom for the elderly life, leisure cultural service facilities, and medical service facilities.

• Journal of Environmental Science International
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• v.12 no.11
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• pp.1181-1187
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• 2003

Hibiscus hamabo, called "Hwang-geun", growing about 3m in height is a deciduous shrub or subtree of Malvaceae. Because the number of these species is very limited in the world, the Ministry of Environment has designated H. hamabo as a preserved plant. The Korea Forest Service also protects it strictly by law since H. hamabo is an out-of-the-way plant and possibly may be exterminated soon in Korea. Investigation for distribution and ecological characteristics of the habitat for H. hamabo was carried out on Soan Island. Two wild H. hamabo were found at the forest edge (equation omitted) along the sea coast located in the southern part of Soan Island and this was the first report in the Korean academic world. These two wild H. hamabos were growing in a naturally inhibited area. The diameters at the base were 12cm and 15cm. The Tree heights were 150cm and 210cm and the number of branches of each wild H. hamabo was 4 and 7. However, the present condition of these plants was not good. Environmental conditions of the naturally inhibited area of H. hamabo were very mild because it is located at the edge of the forest and is always sunny during the daytime since the slope of the inhibited area is facing South. The ground drained very well since the soil was made of gravels and sand. Because the percent of vegetation of the subtree layer where H. hamabo was growing was 40%, the cover degree and sociability of flex crenata trees and Eurya japonica were found to be high. In the naturally inhibited area of H. hamabo, a dominant value of Rubus parvifolius in the lower part of the herb layer was very high and many plants in Compositae, such as Artemisia princeps var. orientalis and Erigeron annuus, were also present. A dominant value of liana, such as Vitis thunbergii var. sinuata, Rosa multiflora, Clematis terniflora and Hedera rhombea, and Gramineae plants that rhizomes were well developed and aggressively propagated, such as Miscanthus sinensis var. purpurascens, Phragmites communis, Spodiopogon cotulifer and Oplismenus undulatifolius which were surveyed as high, too. These results imply that H. hamabo might be exterminated soon through a natural selection if the proper management of the naturally inhibited area of H. hamabo is not conducted continually.

• The Journal of Internal Korean Medicine
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• v.30 no.1
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• pp.153-172
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• 2009

Background : The safety of Korean herbal Medicine (KHM: prescribed herbal medicine by doctors of traditional Korean medicine) is an important issue in Korea. Although both fields. western medicine and traditional Korean medicine. have been studied on the safety of herbs and KHM, their results were not concordance with each other. Objectives : This study aims to review the influence of KHM on liver function in Korean literature systematically. Additionally, we tried to estimate the change of data of liver function test (LFT) and the incidence of liver injury (LI) after the use of KHM. Methods : Systematic literature searches were performed on 4 major databases of Korea from their inception to May 2008. Screening and selection of the studies and the extraction of data were performed independently by two authors. There were no restrictions on the types of publication including grey literatures. Results : Forty studies were included. Only sixteen studies were performed prospectively and fifteen studies collected data from outpatients. Only 8 studies reported the occurrence of LI after the use of KHM. Nineteen cases of LI showed no or mild symptoms and the elevation of LFT was not high. All of LI patients used conventional western drug and KHM concomitantly. and causality of LI was not assessed properly. The incidence of LI related to the use of KHM was estimated as 0.59%-0.76% from all data of these studies. The conflicting results were shown on the change of alanine aminotransferase (ALT) and total bilirubin (TB) after the use of KHM. Conclusions : KHM might be a minor cause of LI in Korea. However the results are not strongly supported as enough to make the safety issue clear because of the limitations of original studies. More rigorous studies are required for answering the safety issue of KHM with the cooperative investigation of both fields of Korean traditional medicine and western medicine.

• Korean Journal of Environmental Agriculture
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• v.40 no.4
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• pp.260-269
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• 2021

BACKGROUND: Diquat dibromide is a fast-acting nonselective herbicide and plant growth regulator. In this study, in order to understand the possibility of unintentional pesticide contamination in the following crops, the phytotoxicity and transition of diquat dibromide residue in soil into the following crops such as pepper, radish, lettuce and corn have been assessed through phytotoxicity trial and residual evaluation in the unintentional contamination of the higher residual diquat dibromide. METHODS AND RESULTS: The pepper, radish, lettuce and corn were cultivated in the sandy soil and loam soil where the 35 mg/kg and 90 mg/kg diquat dibromide were applied, respectively. Mild growth inhibition symptoms were observed in radish, lettuce and corn crops at the 90 mg/kg- diquat dibromide treatment on the 30 day of cultivation. Diquat dibromide was analyzed using liquid chromatography QTRAP (LC-MS/MS). The recovery rates of diquat dibromide from soil and crop were determined within range from 89.1 to 116.4% with relative standard deviation less than 14.7%. Diquat dibromide residues in soil were found to be 23.90-30.22 and 69.59-82.57 mg/kg from the 35 mg/kg and 90 mg/kg of diquat dibromide-treated soil, respectively after 30 days of crop cultivation. This result implicates that diquat dibromide did not convert to metabolites and remained mostly in the soil, even though it was partially decomposed during crop cultivation. In addition, the diquat dibromide in pepper and radish that were grown for 47 days, and lettuce and corn that were cultivated for 30 days were detected to be 0.01 mg/kg or less in the sandy loam and loam soil where the 90 mg/kg diquat dibromide was applied. CONCLUSION(S): Diquat dibromide did not cause severe phytotoxicity in the following crops as well as it did not uptake and distribute to the following crops, even though it was considered to be residual in the soil.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.609-627
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• 2019

The purpose of this study was to explore service satisfaction of the elderly using dementia day care center and the meaning of day care experience. The subjects for this methodological triangulation study were 67 dementia elderly for 1:1 interview and 15 dementia elderly for focus group interview. All subjects were using dementia day care center. The mean age was $79.95{\pm}5.90$ for quantitative study and $80.07{\pm}5.78$ for qualitative study subjects. The mean scores of service satisfaction were ranged from $2.86{\pm}0.41$ to $2.96{\pm}0.30$. The lowest score domain was 'help and assistance', and the highest score domain was 'food and environment'. In 14 questions, satisfaction score was 3 point. According to content analysis, the experiences of dementia day care center were described with 20 themes such as 'mutual respect and understanding', 'pleasure and upset feelings about participation', etc. and 35 sub-themes. The overall satisfaction scores were high and in most cases the positive experiences with dementia day care service were described. Therefore it is recommended for mild dementia elderly to use dementia day care service and to be expanded.