• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.5
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• pp.657-663
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• 2015

Ionizing radiation induces cell damage through formation of reactive oxygen species. The present study was designed to evaluate the protective effects of post-treatment with hesperetin against ${\gamma}$-irradiation-induced cellular damage and oxidative stress in BALB/c mice. Healthy female BALB/c mice were exposed to ${\gamma}$-irradiation and administered hesperetin (25 mg/kg and 50 mg/kg, b.w., orally) for 7 days after 6 Gy of ${\gamma}$-irradiation. Exposure to ${\gamma}$-irradiation resulted in hematopoietic system damage manifested as decreases in spleen indexes and WBC count. In addition, hepatocellular damage characterized by increased levels of aspartate aminoransferase (AST) and alanine aminotransferase (ALT) in plasma. However, post-irradiation treatment with hesperetin provided significant protection against hematopoietic system damage and decreased AST and ALT levels in plasma. The results indicate that ${\gamma}$-irradiation induced increases in lipid peroxidation and xanthine oxidase (XO) as well as decreases in antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase) and glutathione (GSH) in the liver. These effects were also attenuated by post-treatment with hesperetin, which decreased lipid peroxidation and XO as well as increased antioxidant enzymes and GSH. These results show that post-treatment with hesperetin offers protection against ${\gamma}$-irradiation-induced tissue damage and oxidative stress and can be developed as an effective radioprotector during radiotherapy.

• Korea journal of population studies
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• v.28 no.2
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• pp.97-129
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• 2005

Korean society recently witnesses a rapid lllcrease of suicide across all ages. In particular, suicide in old ages jumps up ill a very unexpected way. Furthermore, the order of suicide in the cause of death across all ages is becoming higher and higher in Korea. This study provides details of suicide that occurs in Korean society with the comparison to that of Japan at the descriptive level. It is not well known why suicide in Korean surges recently. Several previous research show the possibility that surging suicide is closely related to the worsened economic conditions especially since the economic crisis in 1997. They adopt economic growth, unemployment rate, income distribution, household finance index as economic indicators in their research. This study also adopts those indicators and conducts a correlation analysis in two periods, 1990-1997 and 1998-2004. It is found that there is no correlation between economic indicators and suicide in the period of 1990-1997. On the other hand, there is a very strong correlation between income distribution and suicide in the period of 1998-2004. Other economic indicators except income distribution does not have any significant correlation with suicide. This finding suggests that currently increasing suicide in Korea may be a result of economic polarization, which has been worsened since the economic crisis in 1997.

• Journal of Naturopathy
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• v.11 no.1
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• pp.18-30
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• 2022

Background: It was to develop an air purification system (APS) using an underground air purification layer to verify the effect of basalt forest's underground air (sumgol) on a volcanic Jeju. Finally, it is necessary to analyze these purified air components and their usefulness to the human body in an air experience center. Purpose: It was to collect basalt forest air, analyze its composition, and explore its effect on the human body. Methods: We APS devices installed at four points in the Papaville area of Jeju. The air discharged from the APS was collected and analyzed the recycling components. An installed experience room filled with negative ions is about 5,000 ions/m³. After allowing the participants to stay for 60 to 120 minutes, we investigated the state of blood vessels. Results: In the analysis of the underground air, the O₂ concentration was 21.18%, which was higher than the average oxygen concentration of 20.94% in the atmosphere. However, Formaldehyde was not detected, and the CO₂ was 419 ppm, which was lower than that of indoor air. The PM2.5 concentration was less than 24 ㎍/m³ and detected anions over 5.000 /m³. The experiencer's vascular states improved, and the increase in pulse rate and stress relief were high. Conclusions: The valuable ingredients identified by analyzing the air were precious for natural healing. The experience results showed that it effectively improved the pulse rate, blood vessels, and stress. These conditions may be highly beneficial as a new area for expanding the basalt lava forest in the Jeju area into the natural healing and wellness industry.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.891-908
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• 2009

This study was performed to investigate the dietary habits, body weight satisfaction and eating disorder tendencies of female university students in Kyungnam province. Anthropometric measurements, dietary habits, body weight satisfaction, food preferences, disordered eating, and nutrient intakes were assessed in 132 female students at Kaya University. The results were analyzed with $x^2$- and ANOVA tests using the SPSS package program. The average age of the subjects was 20.1 years and average body mass index (BMI) were $21.1\;kg/m^2$. According to BMI, the percentages of students who were underweight, normal weight and overweight by BMI were 21.2, 55.3, and 23.5, respectively. Duration of exercise was significantly different by BMI. Index scores for a mini dietary assessment were significantly higher in the normal and overweight groups than in the underweight group. Scores for sweet, salty, and meat preferences were highest and scores for bean and vegetable preferences were lowest, in the underweight group. Satisfaction for present body weight was lowest, and self-perception of body image and weight control experiences were highest in the overweight group. All subjects in the overweight group wanted to be slim, and those in the normal and underweight groups, preferred to be more slim despite their current body weight being in the normal or below normal range. The percentage of the subjects who were at risk for eating disorders (based on scores from the Eating Attitude Test-26, EAT-$26{\geqq}20$) was 11.3%. Scores for EAT-26 were higher in the overweight group than in the underweight and normal weight groups. Nutrient intakes were not different among the groups. Therefore, dietary habits, taste and food preferences, satisfaction for present body weight, and disordered eating were significantly different according to BMI. These results suggest that overweight female university students need help correcting disordered eating, and nutrition counseling should be established to aid desirable weight control methods. Those who are underweight and normal weight need help establishing proper perceptions of their normal body weight and body image as well as nutrition counseling for health.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.329-339
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• 2021

Soybeans (Glycine max), one of major upland crops, require precise management of environmental conditions, such as temperature, water, and soil, during cultivation since they are sensitive to environmental changes. Application of spectral technologies that measure the physiological state of crops remotely has great potential for improving quality and productivity of the soybean by estimating yields, physiological stresses, and diseases. In this study, we developed and validated a soybean growth prediction model using multispectral imagery. We conducted a linear regression analysis between vegetation indices and soybean growth data (fresh weight and LAI) obtained at Miryang fields. The linear regression model was validated at Goesan fields. It was found that the model based on green ratio vegetation index (GRVI) had the greatest performance in prediction of fresh weight at the calibration stage (R²=0.74, RMSE=246 g/m², RE=34.2%). In the validation stage, RMSE and RE of the model were 392 g/m² and 32%, respectively. The errors of the model differed by cropping system, For example, RMSE and RE of model in single crop fields were 315 g/m² and 26%, respectively. On the other hand, the model had greater values of RMSE (381 g/m²) and RE (31%) in double crop fields. As a result of developing models for predicting a fresh weight into two years (2018+2020) with similar accumulated temperature (AT) in three years and a single year (2019) that was different from that AT, the prediction performance of a single year model was better than a two years model. Consequently, compared with those models divided by AT and a three years model, RMSE of a single crop fields were improved by about 29.1%. However, those of double crop fields decreased by about 19.6%. When environmental factors are used along with, spectral data, the reliability of soybean growth prediction can be achieved various environmental conditions.

• Journal of Bio-Environment Control
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• v.31 no.3
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• pp.194-203
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• 2022

Cultivation of tomatoes in Korea grown in soil covers 89% of the total area for tomato cultivation. Tomatoes grown in soil often encounter various environment stresses including not only salt stress and soil-borne diseases but also cold stress in the winter season. This study was conducted to comparatively analyze the performance of rootstocks with cold stress by measuring the growth, yield, and photosynthetic efficiency in tomatoes grown in soil. The rootstocks were used 'Powerguard', 'IT173773', and '20LM' for the domestic rootstock cultivars and 'B-blocking' for a control cultivar. The tomato cultivar 'Red250' was used as the scion and the non-grafted tomatoes. Stem diameter, flowering position, leaf length, and leaf width were investigated for the growth parameters. The stem diameter of the non-grafted tomatoes decreased by 15% compared to the grafted tomatoes at 80 days after transplanting when exposed to low temperatures of 9-14℃ for 14 days. The leaf length and width of the non-grafted tomatoes were the lowest with 42.4 cm and 41.8 cm at 80 days after transplanting. The total yield per plant was the highest in tomato plants grafted on 'Powerguard' with 1,615 g and lowest in non-grafted tomatoes with 1,299 g. As the result of measuring the chlorophyll fluorescence parameters, PI_ABS and DI₀/RC, which mean the performance index and dissipated energy flux, 'Powerguard' was the highest with 3.73 in PI_ABS and the lowest with 0.34 in DI₀/RC, whereas non-grafted tomatoes was the lowest with 2.62 in PI_ABS and the highest with 0.41 in DI₀/RC at 80 days after transplanting. The stem diameter has positive correlation with PI_ABS, while it has negative correlation with DI₀/RC. The results indicate that can be analyzed by chlorophyll fluorescence parameters can be used for analyzing the differences in the growth of tomato plants grafted on different rootstocks when exposed to cold stress.

• 한국사회복지학회:학술대회논문집
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• 2003.10a
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• pp.185-216
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• 2003

This study was aimed at investigating important factors influencing career success among regular workers. The current researcher scrutinized the degree to which variables and factors affect the career success and occupational turnover rates of the research participants. At the same tune, two hypothetical path models established by the researcher were examined using linear multiple regression methods and the LISREL. After examining the differences among the factors of career success, a comparison was made between the disabled worker group and the non-disabled worker group. A questionnaire using the 5-point Likert scale was distributed to a group of 374 workers with disabilities and 463 workers without disabilities. For the data analysis purpose, the structural equation model, factor analysis, correlation analysis, and multiple regression analysis were carried out. The results of this study ran be summarized as follows. First, the results of factor analysis showed important categories of conceptual themes of career success. The initial conceptual factor model did not accord with the empirical one. A three-factorial model revealed categories of personal, family, and organizational factor respectively. The personal factor was composed of the self-esteem and self-efficiency. The family factor was consisted of the multi-roles stress and the number of children. Finally, the organizational factor was composed of the capacity for utilizing resources, networking, and the frequency of mentoring. In addition, the total 10 sub areas of career success were divided by two important aspects; the subjective career success and the objective career success. Second, both research participant groups seemed to be influenced by their occupational types. However, all predictive variables excluding the wage rate and the average length of work years had significant impact on job success for the disabled work group, while all the variables excluding the frequency of advice and length of working years had significant impact on job success for the non-disabled worker group. Third, the turnover rate was significantly influenced by the age and the experience of turnover of the research participants. However, the number of co-workers was the strongest predictive variable for the worker group with disabilities, but the occupation choice variable for the worker group without disabilities. For the disabled worker group, the turnover rate was differently influenced by the type of occupation, the length of working years, while multi-role stress and the average working years at the time of turnover for the worker group without disabilities. Fifth, as a result of verifying the hypothetical path model, it showed that the first model was somewhat proper and could predict the career success on both research participant groups. In the second model, the Chi-square, the degree of freedom (($x^2=64.950$, df=61, P=0.341), and the adjusted Goodness of Fit Index (AGFI) were .964, and the Comparative Fit Index (CFI) were .997, and the Root Mean Squared Residual (RMR) was respectively. .038. The model was best fitted and could predict the career success more highly because the goodness of fit index in the whole models was within the allowed range. In conclusion, the following research implications can be suggested. First, the occupational type of research participants was one of the most important variables to predict the career success for both research participant groups. It means that people with disabilities require human development services including education. They need to improve themselves in this knowledge-based society. Furthermore, for maintaining the career success, people with disabilities should be approached by considering the subjective career success aspects including wages and the promotion opportunities than the objective career success aspects.

• Sleep Medicine and Psychophysiology
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• v.20 no.1
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• pp.22-30
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• 2013

Objectives: Sleep problems has been consistently reported as a suicidal risk factor in adults and, recently, also in adolescents. In this study, dividing study subjects by the previous suicidal behaviors (suicidal vs non-suicidal), we compared the group differences of suicidal risk factors, and examined the possibility of sleep as a suicidal risk factor. Methods: Study subjects were 561 (271 boys and 290 girls) from a community sample of high school students. Suicidal Risk Behavior Checklist, Center for Epidemiological Study-Depression (CES-D), Symptom Checklist-90-Revision (SCL-90-R) Anxiety and Aggression subscale, Pittsburg Sleep Quality Index (PSQI) were done. Results: Forty six students (8.1%) reported previous actual self-harm behavior as a suicidal attempt, 181 students (32.4%) reported having suicidal thought only. Three hundred thirty four students (59.5%) reported no previous suicidal behavior (thought and attempt, both). Suicidal behavior group showed higher score on risk behaviors such as school violence, substance use and internet addiction. CES-D, SCL-90-R, PSQI showed significant group difference. Logistic regression analysis showed suicidal risk were significantly associated with depression, stress in suicidal risk factors and sleep latency, daytime dysfunction in PSQI. Analysis of variance (ANOVA) shows the most prolonged sleep latency and increased index of all PSQI components except sleep efficiency in suicidal attempt group. Conclusions: Sleep Problems had a strong association with the suicidal risk behavior in adolescents. Sleep problems, especially, prolonged sleep latency, daytime dysfunction might be important markers for suicidal behavior. Screening for sleep problems in adolescents are encouraged for the parents, school teachers, and related medical physicians.

• Korean Journal of Environment and Ecology
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• v.19 no.3
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• pp.287-298
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• 2005

This study was carried out to offer the raw data on conservation of land and natural environment by constructing groups of indicators to objectively and rationally assess the sustainable natural ecosystem and present the direction for establishing and planning the environmental policy. There were selected that four assessment items were biotic, abiotic, qualitative, and functional factor. And there were extracted fifty-six indicators including density, total nitrogen, hemeroby degree, and goods production. As assessment items and indicators were over 0.6, the design of questionnaire showed no great problem. In the results of correlation analysis of assessment indicators, sociality and dominance was highly correlative in biotic factor, soil property and aspect in abiotic factor, naturalized and urbanized index in qualitative factor, and protection of landslide and soil erosion were too correlative. In the results of deciding the dimension by multidimensional scaling, as stress values were from 0.042 to 0.133, index of fit over 0.9, there no statistical problems. In case of X axis, biotic factor was structure, viewpoint in abiotic factor, composition in qualitative factor, and object in functional factor, and Y axis was shaped Into form, range, structure, and activity.

• Korean Journal of Ecology and Environment
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• v.45 no.3
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• pp.314-321
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• 2012

To quantitatively assess the effects of turbidity on egg development and larval fish survival, a laboratory fish rearing experiment was applied to different life stages (newly hatched larval stage, juvenile stage and pre-adult stage) of the Zacco platypus, one of the most universal and tolerant species in Korea. According to the stress index of turbidity in water with exposure time, three different treatments, including a reference condition (1~7 NTU) as well as intermediate (20~150 NTU) and high turbidity conditions (400~1,000 NTU) were applied, and egg hatching and larval fish mortality rates were observed. The mortality rates of newly hatched larval fish were significantly different among treatments (ANOVA, $F_{2,3}$=17.79, p<0.05). Average rates of survival to hatching were 20.9% (${\pm}0.1%$) for reference condition, 11% (${\pm}6.9%$) for intermediate level and 3.2% (${\pm}3.7%$) for high level conditions, respectively. A sudden change of mortality at the high level was observed within 5 days of the experiment. About 84% of juvenile fish survived until 20 experimental periods under conditions of reference turbidity, while survival under conditions of intermediate turbidity was over 80% of larval fish until day 13 of the experiment, but dropped to less than 10% after day 14 and 15 of two experiments. Fish mortality appeared from day 6 of the high turbidity experiment, and 50% mortality was achieved at day 9 to 10 of experiment. Full mortality occurred at day 14 of the experiment (RM-ANOVA, $F_{2,38}$, p<0.005). In the pre-adult stage experiment, no mortality was observed during the experiment at reference level treatment (20 days), while only slight mortality rates were observed for both intermediate and high levels until day 5 of the experiment, however, no further fish died in either experiment. It was significantly different compared to reference condition (RM-ANOVA, $F_{2,20}$=8.28, p<0.01), but no difference was observed between intermediate and high level conditions. Consequently, this tolerant species has been determined to be well adapted to high levels of turbidity in its adult stage, but more vulnerable throughout earlier life stages.