• Journal of Korean Society of Forest Science
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• v.96 no.2
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• pp.138-144
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• 2007

This study was undertaken to compare the biomass of Abies koreana growing at two sites. A $10{\times}10m$ plot was established in each site of a natural stand in Mt. Jiri and a plantation in Gyeongsan nursery. Five trees of A. koreana were randomly selected in each site. The following traits were investigated from each tree : height, basal diameter, age, weight of stem, branches, and needles as above-ground traits and weight of total roots, horizontal roots, and vertical roots as below-ground traits. In Gyeongsan nursery, age of sample trees was negatively correlated with both height and weight of total stem, while height was highly correlated with weight of horizontal roots. There was high correlation between the basal diameter and weight of total stem, and between the basal diameter and weight of roots. In Mt. Jiri stand, most of the above-ground traits except age were significantly correlated with the below-ground traits. The linear regression equation between the cross section area of base (X) and the weight of total stem (Y) in Gyeongsan nursery was Y=12.66X-12.92, and correlation was significant ($R^2=0.89$). The linear regression equation between the cross section area of base(X) and the weight of total branches (Y) in Mt. Jiri stand was Y=25.51X+6.00, and correlation was highly significant ($R^2=1.0$).

• The Journal of Information Systems
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• v.30 no.3
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• pp.113-135
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• 2021

Purpose This study aims to measure the effects of media literacy education through the social science method and find out the impact of media literacy education on digital citizenship in Korea and its implications for the development of democracy. Design/methodology/approach This study used an independent t-test to analyze relativeness between media literacy education and media literacy factors. We also adopted an independent t-test to investigate media literacy influence on digital citizenship. Furthermore, we found out age differences using 'the one-way analysis of variance (the one-way ANOVA)'. Findings We have found four media literacy factors, MC, CT, C&P, R&R, have been significantly affected by media literacy education. We have also pulled out three digital citizenship factors, IPA, TS, and CP, involved in media literacy education. Moreover, we have analyzed our survey by different age groups. The lower the age, the higher the TS. CP was highest among those from 30 to 59, followed by those under the 30s.

• Archives of Craniofacial Surgery
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• v.20 no.3
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• pp.158-163
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• 2019

Background: Age-related changes in facial skin is a major concern in women. This study aimed to objectively evaluate normal skin elasticity and age-related differences in the faces of East Asian women. There are no standard values for data related to normal skin on East Asian women. Methods: We studied 129 healthy East Asian women without a history of cosmetic procedures or surgeries. Skin elasticity was assessed at the cheek and lower eyelid points, which were assessed on both the right and left sides of the face. Results: The age of the subjects showed significant negative correlations with the R2 and R7 parameters, which represent skin elasticity after deformation. Conclusion: We therefore concluded that the primary decrease in skin elasticity in East Asian women occurs in the midface region.

• Tuberculosis and Respiratory Diseases
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• v.51 no.3
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• pp.248-259
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• 2001

Background : In diagnosis or monitor of the airway obstruction in bronchial asthma, the measurement of $FEV_1$ in the standard method because of its reproducibility and accuracy. But the measurement of peak expiratory flow(PEF) by peak flow meter is much simpler and easier than that of $FEV_1$ especially in children. Yet there have been still no data of the predicted normal values of PEF measured by peak flow meter in Korean children. This study was conducted to provide equations to predict the normal value of PEF and correlation between PEF and $FEV_1$ in healthy children. Method : PEF was measured by MiniWright peak flow meter, and the forced expiratory volume and the maximum expiratory flow volume curves were measured by Microspiro HI 501(Chest Co.) in 346 healthy children(age:5-16 years, 194 boys and 152 girls) without any respiratory symptoms during 2 weeks before the study. The regression equations for various ventilatory parameters according to age and/or height, and the regression equations of $FEV_1$ by PEF were derived. Results : 1. The regression equation for PEF(L/min) was: $12.6{\times}$age(year)+$3.4{\times}$height(cm)-263($R^2=0.85$) in boys, and $6{\times}$age(year)+$3.9{\times}$height(cm)-293($R^2=0.82$) in girls. 2. The value of FEFmax(L/sec) derived from the maximum expiratory flow volume curves was multiplied by 60 to compare with PEF(L/min), and PEF was faster by 125 L/min in boys and 118 L/min in girls, respectively. 3. The regression equation for $FEV_1$(ml) by PEF(L/min) was:$7{\times}$PEF-550($R^2=0.82$) in boys, and $5.8{\times}$PEF-146 ($R^2=0.81$) in girls, respectively. Conclusion : This study provides regression equations predicting the normal values of PEF by age and/or height in children. And the equations for $FEV_1$, a gold standard of ventilatory function, was predicted by PEF. So, in taking care of children with airway obstruction, PEF measured by the peak flow meter can provide useful information.

• The Journal of Internal Korean Medicine
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• v.41 no.3
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• pp.434-446
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• 2020

Objectives: The cardio-ankle vascular index (CAVI) and ankle-brachial index (ABI) are non-invasive methods to evaluate cardiovascular disease and arteriosclerosis. This study investigated the relationship between CAVI, ABI, and factors related to arteriosclerosis. Methods: This study included 535 healthy adults who underwent health examinations in 2019. We analyzed the correlation between CAVI, ABI and clinical variables. Multiple regression analysis was performed on the independent clinical variables associated with CAVI and ABI. Results: The correlation analysis of CAVI showed that body mass index (BMI) and HDL-cholesterol (HDL-C) had a negative correlation, and the other variables had a significant positive correlation. The correlation analysis with ABI on the right side showed that age, diastolic blood pressure (DBP), gender, and LDL-cholesterol (LDL-C) had a significant positive correlation, while HDL-C had a significant negative correlation. There was no statistical significance on the left. In the multiple regression analysis, DBP, age, BMI, gender, and HDL-C were proved to be independent factors in CAVI (right) (R²=0.365); DBP, age, gender, BMI, fasting blood sugar, and total cholesterol in CAVI (left) (R²=0.357); and age, gender, DBP, and systolic blood pressure in ABI (right) (R²=0.133). There were no statistically significant factors in ABI (left). It could be inferred that smoking and drinking are determinants that play an important role in CAVI. Conclusion: CAVI showed a high correlation with gender, age, and blood pressure. A significant correlation between CAVI and serum lipid values could be observed, but this showed a low correlation coefficient. ABI showed a high correlation with age and DBP. These results support the use of CAVI and ABI as primary diagnostic devices in medical treatment.

• Journal of the korean academy of Pediatric Dentistry
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• v.24 no.3
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• pp.610-627
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• 1997

The purpose of this study was to compare the caries activity and cariogenic factors in children in different residence areas. The subjects of the study were 268 kindergarten children who were selected from the downtown area(D), apartment area(A), suburban area(S), and rural area(R) in and around the city of Iksan, Korea. Caries activity was measured as past caries experience (dft index and dfs index) and salivary reductase activity (Resazurin Disc Test scores). Cariogenic factors were investigated by a questionnaire. The results were as follows: Reductase activity S > R > D > A dt index R, S > D, A ft index D - the highest dft index A - the lowest ds index R - the highest fs index D - the highest Toothbrushing frequency A - the highest, R - the lowest Toothbrushing before bed D, A > S, R Toothbrushing by parents S, R > A, D Sweets intake freqeuncy A - the highest, S - the lowest Distance to dental office D < A < S < R Dental treatment experience D - the highest, A - the lowest Flouride application rate D > S > R > A Sealant application rate D > A, S > R Birth order A, S > R, D Age D > S > R, A

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.12
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• pp.1757-1762
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• 2011

Aflatoxins are natural contaminants of poultry feeds and feed ingredients and cause liver damage, immunosuppression, reduction in performance and mortality in broilers. A number of studies have been carried out to study the effects of aflatoxin on feed conversion ratio in broilers. The results on feed conversion ratio of 10 research articles in broilers fed with aflatoxin from first day of age to six weeks of age were compiled and were subjected to meta-analysis. Chi-square test and $Tau^2$ (heterogeneity co-efficient) were applied to test for significance of heterogeneity of studies. To integrate results, fixed effect model by Inverse Variance method (IV method) was used when heterogeneity was insignificant and otherwise random effect model by DerSimonian and Laird Method (DL method) was used. The results of meta-analysis showed that the adverse effect of aflatoxin on feed conversion ratio at the end of first week was negligible, second week was medium and third to six weeks was very large.

• 보존과학연구
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• s.31
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• pp.173-202
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• 2010

Within the framework of the Mongolian-Korean Joint Project for "Research and Preservation of Cultural Heritage", I enrolled in 3 months training course from February to May 2010 at the Metal laboratory of Conservation Science Division in National Research Institute of Cultural Heritage, Korea. Some metal artifacts, which are preserved in Institute of Archaeology, Mongolian Academy of Sciences, were brought and restored there. These chosen findings were found at Gobi and mountainous region of Mongolia, preserved under the different circumstances and dated back to Middle Age from Bronze Age. At the Metal laboratory of the NRICH, the conservation work was carried out for three months on 15 metal objects, including arrowhead, stirrup, caltrop, axe, knife, ring and so on, which were found at Khugshin Teel's ruin of Khairkhandulaan soum of Uvurkhangai province, Ungut of Altanbulag soum of Tuv province, Baruun Naran and Ukhaa khudag of Khankhongor and Tsogttsetsii soums of Umnugobi province. The report of the result of this conservation work is available here.

• Journal of Preventive Medicine and Public Health
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• v.12 no.1
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• pp.79-87
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• 1979

Analyses for 6 metals (Cd, Zn, Cu, Ni, Pb, Mn) by Atomic absorption spectrophotometer were made on hair samples of healthy 135 in urban area and 130 in rural area who have not dealt with the above metals in their daily working life. Marksd variations were found. Samples of urban area contained more cadmium, copper, lead and manganese than those of rural area. No sexual difference in mean value could be observed and the amount of metals in hair did not increase with age. And no age dependency was found. There was a statistically significant correlation between the concentrations of cadmium and lead in both urban and rural people; Pb = 1.50 Cd + 6.69 (r = 0.213, p<0.05) in urban area Pb = 1.44 Cd + 3.67 (r = 0.327, p<0.001) in rural area

• Clinical and Experimental Pediatrics
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• v.50 no.11
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• pp.1091-1096
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• 2007

Purpose : The of common carotid artery intima media thickness (IMT) is an acknowledged noninvasive marker for early atherosclerotic changes. We investigate whether common carotid IMT is different between obese and normal-weight children and also evaluate the relationships IMT with cardiovascular risk factors. Methods : We collected the clinical data (age, sex, pubertal stage, body mass index) and measured blood pressure, glucose, insulin, lipid profiles and adiponectin in 49 obese children (mean age, 12 years) and 24 nonobese children as controls. The control group was composed of 24 nonobese children of the same age, sex and pubertal stage. We measured the carotid IMT of all subjects by B-mode ultrasound with a 7.5-MHz linear transducer and analyzed. Results : Obese children demonstrated a significantly thicker intima media (mean, 0.34 mm, peak, 0.42 mm) compared to the control group (mean, 0.31 mm, peak, 0.38 mm, P<0.01). IMT was significantly correlated to the BMI (r=0.431, P<0.01), age (r=0.317, P<0.01), total cholesterol (r=0.377, P< 0.01), triglyceride (r=0.253, P<0.05) and low-density lipoprotein cholesterol (r=0.289, P<0.05). Serum adiponectin was significantly lower in obese children than in controls (11.2 ng/mL vs. 14.7 ng/mL, P<0.05) and negatively related with IMT (r=-0.267, P<0.05). Conclusion : Obesity is associated with increased carotid artery IMT in children. Our results suggest vascular changes in obesity seem to occur already in childhood and vascular ultrasonography may helpful for screening cardiovascular complications in obese children.