• Journal of The Korean Society of Grassland and Forage Science
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• v.25 no.3
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• pp.177-184
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• 2005

This study was conducted to study the effect of fiber sources on ruminal pH and buffering capacity and whole digestive tract digestibility with five ruminally fistulated sheep. Evaluated fiber sources were alfalfa hay cube (AHC), corn cob (CC), com silage (CS), cotton seed hull (CSH), peanut hull (PHL), rice straw (RS), and sugarcane bagasse (SCB). Sheep were fed consecutively a diet containing each tested fiber source $(45\%)$ with a corn-based concentrate diets $(55\%)$ during each experimental period. Ruminal pH showed no difference among fiber sources except the significantly lower pH at 8h (p<0.05) with RS (pH; 5.78) than those in other sources. Buffering capacity showed significant differences at 0h (p<0.05) and 2h (p<0.05) after feeding in CS compared to those from SCB and CC, while there was higher in PHL (p<0.01) at 12h post feeding except AHC than CC, CS, SCB, and RS. Dry matter digestibility was significantly higher in CS (p<0.001) than in other sources. Neutral detergent fiber digestibility was higher in CC, CS, CSH, and RS than other fiber sources (p<0.001). These results suggest that ruminal pH and buffering capacity and whole digestive track digestibility were significantly affected by fiber sources in ruminant diet, and, therefore, should be took those effects into account for TMR formulation.

• The Journal of the Korea Contents Association
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• v.14 no.3
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• pp.241-249
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• 2014

The aim of this paper is to examine the buffering effect of family cohesion in the relationship between depression and suicidal risk among adolescents, adults, and the elderly. To achieve the research aim, surveys were conducted in 10 cities across the country for 399 adolescents, 473 adults, and 370 elderly from May to August 2010. Major findings of the data analysis are as follows. First, while, in the relationship between depression and suicidal risk, the elderly were the highest, followed by adolescents and adults in descending order, in family cohesion, adults were the highest, followed by the elderly and adolescents. Second, the analysis of the buffering effect of family cohesion in the relationship between depression and suicidal risk showed that it was significant only for adolescents and adults, which means that for those two groups family cohesion alleviates the effects of depression on suicidal risk, demonstrating the necessity of strengthening family cohesion to reduce suicides among the two groups of people. But, for the elderly for whom family relationship is more important than any other age group, the buffering effect of family cohesion in the relationship between depression and suicidal risk was not proved. The interpretation of this phenomenon is given in the part of the paper where the characteristics of the suicide of the old age group is discussed.

• Journal of Korean Society of Water and Wastewater
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• v.22 no.5
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• pp.581-587
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• 2008

In this study, we investigated the buffering effect with different COD, $NH_4{^+}-N$ and TP shock loads on the performance of lab-scale Sequencing Batch Reactor(SBR) using synthetic wastewater. This study was operated under the following conditions : HRT, 12 hrs : MLSS, 2,000 mg/L : F/M ratio, $0.2kgCOD/kgMLSS{\cdot}d$ : SRT, 20days, and was increased by a factor, COD : ranging from 200-2000 mg/L, $NH_4{^+}-N$ : ranging from 30-300 mg/L, T-P : ranging from 5-50 mg/L in the reactor. As results, COD removal rate at different shock loads was decreased until 42.1%(stable state : 95%) and concentration with effluent was higher than 695 mg/L(at Run 6). In case of $NH_4{^+}-N$ removal rate was decreased until 35.8% from 97.0% and also T-P removal rate was decreased until 5.0%. Effluent concentrations of COD, $NH_4{^+}-N$ and T-P were rapidly increased according to shock loads and needed 3, 4 and 6 additional cycle times for recovering the stable condition.

• Journal of Families and Better Life
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• v.25 no.5
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• pp.107-126
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• 2007

This study explored the buffering effect of family resilience between family stress and adjustment of single parent family based on family resilience approach. Results of the study were as followed: First, single parents who had a lower level of family stress and a higher lever of family resilience reported a higher level of family adjustment. Second, family stress especially economic stress and relational stress influenced negatively on adjustment of single parent family. Family belief system, organizational pattern and communication processes of the three sub-factors of family resilience influenced positively on family adjustment. However the sub-factors of family resilience had more powerful effects than family stress. Third, family belief system, organizational pattern and communication processes of the three sub-factors of family resilience had a moderating effect between family adjustment and psychological stress and between family adjustment and relational stress. Especially the three sub-factors of family resilience had a buffering effect between family adjustment and relational stress. The results of this study had important implication for theory, research, and practice. The study showed that adjustment of single parent family could be significantly explained by family resilience rather than family stress. Accordingly strength perspective-based intervention focused on family resilience would be more effective than deficit perspective-based intervention based on family stress.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.5
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• pp.1-12
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• 2015

This study analyzes the physiological healing effects on users according to forest types. Forest types are classified into Chamaecyparis obtusa, Quercus serrata and Pinus densiflora and the subjects of this study, 64 hypertensives, 59 diabetics and 59 ordinary people, were tested to observe their physiological effects. The index of physiological reaction comprises electroencephalogram(EEG), heart rate variability(HRV), blood pressure and cortisol level. An analysis of the stress-buffering effect from the physiological reactions of the overall subjects indicates that Quercus serrata forests have a higher stress-buffering effect than others in terms of central nervous, endocrine and autonomic nervous systems. Chamaecyparis obtusa forests are contributory to soothing stress in the central nervous and endocrine systems. Pinus densiflora forests contribute in some indexes of the endocrine and autonomic nervous systems. In contrast, Pinus densiflora forests are less influential on a stress-buffering effect than the other two. In the level of the effect for lowering blood pressure, Chamaecyparis obtusa and Quercus serrata forests are more effective than Pinus densiflora forests. Therefore, staying in the first two forests can heighten the healing effect of the lowering of blood pressure for hypertensive patients. Every forest is efficacious to lowering diabetic blood glucose levels. Spending time in Quercus serrata forests is more effective for hypoglycemic.

• Perspectives in Nursing Science
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• v.13 no.2
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• pp.70-80
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• 2016

Purpose: This study examined the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea, focusing on the buffering effects of social support. Methods: We included 132 completed questionnaires in the analysis. The buffering effect was examined using a hierarchical regression analysis by adding interaction terms. Results: Health promotion scores were significantly higher in the group with a higher education level, lower depressive symptom scores, and higher levels of social support. However, no statistically significant differences were found in the health promotion behaviors by gender, age, spouse, job, financial stability, subjective health status, chronic disease, regular health checkups, or acculturation stress. The hierarchical regression analysis demonstrated that social support had a buffering effect on the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants. Specifically, the relationship between the acculturation stress stemming from the difficulties in the workplace and health promotion behaviors was attenuated by social support. Conclusion: These findings indicate that social support significantly moderates the relationship between acculturation stress and health promotion behaviors in the Korean Chinese elderly immigrants living in Korea. A variety of strategies to enhance social support should be incorporated in the health promotion programs to decrease the negative effects of acculturation stress in the Korean Chinese elderly living in Korea.

• Journal of Preventive Medicine and Public Health
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• v.29 no.2 s.53
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• pp.295-309
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• 1996

The purpose of this study is to investigate the effect of job stress and social support on the organizational effectiveness of hospital employees and to examine the role of social support in the experience of job stress among the employees. Previous studies have yielded mixed results regarding the role of social support. Some studies provide supporting evidence for the buffering effect of social support, while others do not. Still others report findings about reverse buffering effects. These inconsistent findings are, in part, accounted for by methodological problems such as poor measurement, small sample size, and the existence of high multicollinearity. To examine more rigorously the role of social support in relation to the negative effects of job stress, this study was carefully designed to overcome methodolgical shortcomings found in the past research. In addition, unlike the previous studies, which were concerned mostly with health-related variables as consequences of job stress, in this study, three work-related variables (job satisfaction, organizational commitment, and intent to stay) which had close relationships with organizational effectiveness were examined as output variables. The sample used in this study consisted of 353 employees from a university hospital in the surburbs of Seoul. Data were collected with self-administered questionnaires and analyzed using canonical analysis and hierarchical regression analysis. The results of this study indicate that; (1) job stress has negative main effects on job satisfaction, organizational commitment, and intent to stay; (2) social support has positive main effects on the same three output variables, (3) social support does not moderate the harmful effects of job stress on the three outcome variables, and (4) the three-way interaction effects of (social support * job stress * gender) and of (social support * job stress * education) are not supported. The implications of these findings for the management of human resources are discussed.

• Economic and Environmental Geology
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• v.32 no.1
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• pp.53-62
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• 1999

The possibility of heavy metal pollution by contaminated roadside soils was studied under controlled conditions. The soil samples from roadside and those from a retention pond consisting of settling particles were characterized by the XRD analyses and the sequential extraction experiments. Characterization by sequential extraction, for roadside soil indicates elevate total concentrations of heavy metals. The leaching behavior of the samples under different pH and time conditions were also studied. Differences between both types of samples result mainly from the buffering effect of carbonates, present in roadside soils and lacking from settling particles. Acid leaching of the settling particles is equivalent to the sum of FI+FII+FIII, while the amounts leached from roadside soil are lower probably from kinetic reasons. The buffering effects of carbonates were found to greatly delay the onset of the leaching reactions and the extent of dissolution in most metals except for Ca and Mn. The study of leaching kinetics at pH of 6.5 and 5 showed that Cd and Zn reached the maximum possible concentration within 3 days, while Pb did not show any sign of dissolution at both ph values. The absolute amounts of dissolved Cd and Zn increased by 7 to 9 times by decreasing the pH from 6.5 to 5, indicating slightly acidified rain may result in significant metal dissolution. As deduced from both sequential extraction and leaching experiments, the relative mobility of heavy metals is found to be : Mn=Cd>Zn>>Pb>Fe, in spite of large differences in heavy metal contents and localizations.

• Journal of Korean society of Dental Hygiene
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• v.20 no.3
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• pp.387-397
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• 2020

Objectives: This study aimed to evaluate the inhibitory effects of probiotics containing Lactobacillus reuteri on Streptococcus mutans and Aggregatibacter actinomycetemcomitans. In addition, the degree of biofilm formation, initial acidity, buffering ability, and acid production performance were measured to confirm the dental caries-inducing ability. Methods: S. mutans (KCTC3065) and A. actinomycetemcomitans (KCTC2581) were used as experimental strains. The number of viable cells, degree of biofilm formation, initial pH, buffering capacity, and production performance were measured for comparing L. reuteri-containing probiotics and Bulgaris. Results: The viability of S. mutans in the groups was reduced in the following order: Bulgaris, probiotics, control. The degree of biofilm formation was significantly higher at 0% and gradually reduced at different concentrations (p<0.01). At 2.5%, the absorbance of the probiotics and Bulgaris groups differed significantly (p<0.01). The acid formation ability differed significantly based on the performance of S. mutans in each product (p<0.05). The absorbance of the probiotics group was significantly lower than that of the Bulgaris group (p<0.01). Conclusions: This study suggests that the use of L. reuteri-containing probiotics as an adjuvant for the prevention and decreasing of oral diseases may reduce their incidence, which can be considered one of the benefits of using probiotics.

• Journal of dental hygiene science
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• v.24 no.1
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• pp.54-61
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• 2024

Background: The Korean name for Angelica gigas Nakai (AGN) is Cham-dang-gui, which grows naturally or is cultivated, and its dried roots are used in traditional herbal medicines. The AGN root exert various pharmacological effects. Despite the various pharmacological effects of the AGN root, there are no reports on its anti-oral microbial effects. The purpose of this study was to reveal the anti-oral microbial effect and the microbial and biochemical changes in oral microorganisms according to the concentration of the ethanol extract of AGN (EAGN) root, and to confirm the possibility of using EAGN as a plant-derived functional substance for controlling oral infectious microorganisms. Methods: Disk diffusion test, growth measurement, biofilm formation assay, and measurements of acid production and buffering capacity were performed to confirm the antibacterial effect of EAGN. Results: EAGN showed anti-oral bacterial effects against Streptococcus mutans and Aggregatibacter actinomycetemcomitans at all concentrations, with S. mutans showing a more susceptible effect at concentrations above 5.0 mg/ml and A. actinomycetemcomitans at 3.75 mg/ml. EAGN treatment significantly reduced A. actinomycetemcomitans growth at all concentrations tested. Biofilm formation was significantly reduced at concentrations above 3.75 mg/ml for S. mutans and 2.5 mg/ml for A. actinomycetemcomitans. Acid production in S. mutans and A. actinomycetemcomitans was significantly increased by treatment with EAGN, and the buffering capacities of S. mutans and A. actinomycetemcomitans increased from an EAGN concentration of 3.75 mg/ml and above. Conclusion: EAGN showed anti-oral bacterial effects against both S. mutans and A. actinomycetemcomitans at concentrations above 3.75 mg/ml, which were thought to be related to the inhibition of their growth and biofilm formation. Therefore, EAGN can be used as a safe functional substance derived from medicinal plants owing to its antibacterial effects against S. mutans and A. actinomycetemcomitans.