• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.15 no.1
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• pp.71-81
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• 2005

The purposes of this study was to collect, analyze, and describe the MF exposure levels from subways in Korea and to measure and evaluate the MF levels generated from electric appliances used at general homes. The target subway lines were Seoul Metropolitan Line 1 to Line 8, Bundang Line, Incheon Line, Daegu Line, Gwangju Line, and Busan Line 1 and Line 2. We measured at each station in those subway lines and, all the train types (pantograph-equipped, motor-equipped, and common), and platform types(facing and isolating) were investigated by the distance(80, 200, 400 cm) from the train on 19 targeted subway lines using 3 magnetic field measuring devices (EMDEXII, Enertech Co.) during the survey from January till October, 2004. On the other hand, the levels of the 60Hz magnetic fields generated from 14 items of home electric appliances such as electric blankets, hair dryers, electric razors, etc. were measured at 10 general homes using 5 EMDEXII meters with a sampling interval of 1.5 second by the distance(surface, 30, 50, 100, 300cm ) from the target electric appliances. The survey results in the whole subway lines examined in this study were as follows; Seoul Metropolitan Line 4 using AC(alternating current) power source showed the highest mean value of $2.85{\mu}T$, followed by Seoul Metropolitan Line 1 running between Seoul and Incheon using AC($2.78{\mu}T$), Seoul Metropolitan Line 1 between Seoul and Uijongbu using AC($2.73{\mu}T$), Bundang Line using AC($1.79{\mu}T$), Seoul Metropolitan Line 1 connected from Yongsan using AC($1.67{\mu}T$), Seoul Metropolitan Line 1 between Seoul and Suwon using AC($0.79{\mu}T$), and so on. In general, the intensity of the magnetic field in the subway systems in Korea was significantly higher when using AC($2.14{\pm}0.91{\mu}T$) than when using DC($0.29{\pm}0.44{\mu}T$) power source. Among the home electric appliances examined, microwave ovens showed the highest mean value of $7.69{\mu}T$, followed by hair dryers($6.47{\mu}T$), vacuum cleaners($5.27{\mu}T$), televisions ($2.26{\mu}T$), electric blankets($1.38{\mu}T$), personal computers ($0.81{\mu}T$), and so on. Two items of electric appliances showed the excess value of $0.2{\mu}T$ at the distance of 30cm in the MF exposure level; electric razors $1.58{\pm}2.13{\mu}T$ and vacuum cleaners $0.48{\pm}0.44{\mu}T$. As a whole, this study showed a tendency that the shift of the MF levels according to the increase of distance from the electric appliances was lower than those of the results surveyed in UK and USA. As a result, this study is expected to suggest meaningful data for the future study in exposure assessment of magnetic fields and for the establishment of guidelines for subways and electric appliances in Korea. More detailed and large scaled exposure assessment studies should be performed continuously to get the various and useful information on health risk assessment of MFs in Korea.

• The Journal of Korean Academy of Prosthodontics
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• v.48 no.3
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• pp.209-214
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• 2010

Purpose: The purpose of this study was to investigate whether the re-osseointegration of the implants that had mechanical unscrewing possibly occurred or not. Furthermore, if it happened, the degree of re-osseointegration was evaluated by comparing with previous osseointegration. Materials and methods: The smooth implant (commercial pure titanium 99%) specimens, whose diameter and length was 3.75 mm, 4 mm, respectively were produced. Two implants were inserted into each tibia of 7 New Zealand female white rabbits weighing at least 3.0 kg. The torque removal force for each implant after 6 weeks of implants placement was measured and included in group I. The torque removal forces were assessed after the fixtures were re-screwed to original position and the subjects were allowed to have 4 more weeks for healing and included in group II. One rabbit was sacrificed after first measurement and produced 4 slide specimens in group I, and two rabbits were sacrificed after 2nd measurement, 7 slide specimens, in group II for histomorphologic investigations. All slide specimens were assessed based on the proportion of BIC (bone-implant contact) as well as CBa (Bone area in the cortical passage) value produced by counting the screw threads embedded in the compact bones under the optical microscopic analysis (${\times}20$). Statistical analysis was conducted to evaluate the torque removal force, BIC and CBa between group I and II. Results: As for the torque removal force, the result was $10.8{\pm}3.6$ Ncm for group I and $20.2{\pm}9.7$ Ncm for group II. Furthermore, the torque removal force of group II increased by 98.1% in average compared to group I (P<.05). On the other hand, histomorphologic analysis displayed that there was no statistical significance in BIC and CBa values between group I and the group II (P>.05), and RT/BIC and RT/CBa between group I and group II were statistically significant (P<.05). Conclusion: It is possible to obtain more substantial re-osseointegration within shorter periods than the period needed for the initial osseointegration in case of iatrogenically unscrewed implants.

• Korean journal of applied entomology
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• v.58 no.4
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• pp.321-327
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• 2019

When Aphidius colemani mummies were stored at four different temperatures (6, 8, 10 and 12 ± 1℃), they could be stored at 8℃ for 10 days with over 50% adult emergence. A number of mummies of Rhopalosiphum padi parasitized by A. colemani adults emerged from mummies after 8℃ storage clearly reduced with increasing duration of storage and especially declined with storage longer than 13 days showing < 20% parasitism. However, there were no differences in aphid parasitisms by A. colemani on 3 to 10 days after storage. Over 3 day storage at 8℃ was adversely affected on survival of A. colemani adults. Therefore, cold storage of A. colemani adults is considered as an unsuitable method for mass production of biological control agent. When 2-day-old Meteorus pulchricornis cocoons were stored at 6, 8 and 10 ± 1℃, it was possible to be stored up to 63 days at 8℃, showing the highest emergence. With increasing of cold storage duration at 8℃, parasitism on 2^nd and 3^rd larval instar of Spodoptera litura by stored M. pulchricornis significantly reduced. However, parasitic rate by M. pulchricornis stored for 2 weeks was similar to that by 1 week stored ones. Therefore, M. pulchricornis cocoons could be stored up to 2 weeks at 8℃ for stockpiling before release.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.1
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• pp.183-192
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• 2001

The purpose of this study is to verify the relation between vegetarian diet and the risk factors of cardiovascular disease. To do the present study the vegetarians were selected; 127 Buddhist nuns (age : 23 ~ 79 yrs) from Oonmoon Temple in Choungdo District, Gyeongsang Book-do. For control subjects, 235 healthy female adults (age : 23~79yrs) were selected. They were the teachers, the nurses of the hospital of Gyeongsang National University and the housekeepers living in Chinju Gyeongsang Nam-do. This study was conducted from October 1996 to February 1997. The contents are consisted of anthropometric measurement, questionnaries about eating behavior and intake frequency of food group and clinical examination. The results were summarized as follows. The average ages of vegetarians and non-vegetarians were 44.2 yrs and 40.5 yrs respectively. Average body mass index (BMI) of vegetarians and non-vegetarians were 22.4 and 21.0, WHR were 0.8 and 0.8, percentage of body fat were 28.7 and 26.5 and the average duration of vegetarian diet of the vegetarians was 13.1 years. Eating behavior score of vegetarian was significantly higher than those of non-vegetarians. Eating behavior score was negatively of correlated with levels of serum total-cholesterol, LDL-cholesterol and atherogenic index (AI). In intake frequency of green vegetable, lemon-yellow vegetable, bumb and seaweeds of the vegetarians more than those of non-vegetarians. Levels of total cholesterol, LDL-cholesterol, AI, diastolic blood pressure, blood sugar and HDL cholesterol of non-vegetarians were significantly higher (p<0.01) than those of vegetarians, but ratio of HDL cholesterol/total-cholesterol was lower in non-vegetarians. Consequently, vegetable diet can be considerably diet help to decrease the risk of cardiovascular disease.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.147-155
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• 1987

In order to examine the effect of dietary fish oil on lipid peroxide formation and antiperoxidative efficiency in liver and brain, a group of male and female rats weighing about 70 grams were fed for three months, diet containing mackerel oil(MO) at the level of 10% (w/w). Results were compared, according to sex and source of dietary fat, i.e., in addition to MO, perilla oil(PO), soybean oil(SO), rapeseed oil(RO) or beef tallow(BT). Liver lipid peroxide level was significantly higher and levels of ${\alpha}-tocopherol$ and reduced glutathione(GSH) were lower in MO group than in other groups. This phenomenon was less clear in male than in female. Liver GSH level was lower in male, compared to female, but oxidized glutathione (GSSG) level did not vary, depending on either sex or dietary fat source. Brain lipid peroxide and ${\alpha}-tocopherol$ levels were not different among five experimental groups. Activities of liver and brain glutathione peroxidase and superoxide dismutase were not changed by dietary fat source, but glutathione peroxidase activity was higher in female than in male. The present study shows (a) that there is sex-related difference in antiperoxidatiye activity and (b) that fish oil containing $C_{20-22}({\omega}3)$ fatty acids, increases body lipid peroxide level and consumes more of cellular antioxidant, although it has lower total PUFA content than perilla or soybean oils.

• Journal of Korean Society of Forest Science
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• v.70 no.1
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• pp.91-102
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• 1985

Growth and biomass production of natural stands of Quercus variabilis in relation to tree density were studied to obtain basic guide lines for future tending operation. Two natural stands of Quercus variabilis located at 900m (A stand: 6,600trees/ha, $15.84m^2/ha$, $\frac{19}{17-20}$) and 800m (B stand: 4,300trees/ha, $16.65m^2/ha$, $\frac{20}{17-21}$) elevation in Sancheong, Kyongnam Province were selected for the comparative study and following results were obtained through a sample plot method. After diameter of individual trees in the sample plots was measured, twelve average trees from each diameter class were cut felled to measure dry weight of $W_S$, $W_B$, $W_L$, $W_{Ba}$, and standing biomass and biomass production rates by a allometrior regressions related to $D^2H$. Vertical distribution of leaves along the stems indicated that photosynthesis was carried out 2.2m above the ground in Stand A and 1.2m in Stand B. Maximum photosynthesis was located 4.2m and 6.2m above the ground in Stand A and B, respectively. Leaf area index was 4.25ha/ha for Stand A, and 3.89ha/ha for Stand B. Above-ground standing biomass was 49.51 ton/ha for Stand A and 59.20 ton/ha and net annual production was 6.75 ton/ha/yr. for Stand A and 8.99 ton/ha/yr. for Stand B. The ratio of net annual production to standing biomass was 17.5% for Stand A and 16.7% for Stand B. Net assimilation rate was 2.75kg/kg/yr. for Stand A and 3.58kg/kg/yr. for Stand B. Stem wood production rate was 1.46kg/kg/yr. for Stand A and 2.09kg/kg/yr. for Stand B. Bark production rate was 0.60 kg/kg/yr. for Stand A and 0.34kg/kg/yr. for Stand B. Above data indicated that Stand B utilized growing spaces and sites more efficiently than Stand A. It is concluded chat productivity of natural stands of Quercus variabilis can be enhanced through optimization of basal areas and number of tree per hectare and that sound management of natural oak stands should be based on systematic sampling of the area for periodic productivity estimation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.4
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• pp.439-446
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• 2007

This study was performed to investigate the effect of long-term administration of Saengshik on growth parameters of growing rats. Male Sprague-Dawley rats were fed on AIN-93G basal diets for 12 weeks and assigned to the following groups: rats administrated orally with Saengshik at the dose of 1g/kg/day (1xJS ), 2g/kg/day (2xJS), 4g/kg/day (4xJS) and distilled water (Control). Rats were sacrificed at 4, 8, 12 weeks after oral administration. Bone mineral density (BMD) and bone mineral contents (BMC) were measured by PIXImus densitometry and serum insulin-like growth factor-1 (IGF-1) concentration were determined by using EIA method. Body weight and food intake did not show significant changes within groups for 12 weeks. Physical longitudinal growth indexes, body length and femur length were significantly increased in Saengshik-administered groups at 12 weeks, in which BMD and BMC also significantly increased. Also, in blood IGF-1 level, Saengshik-administered groups were remarkedly higher than control group at 4 week (p<0.001), in which significantly higher at 8 week and 12 week. These results suggest a close relation between administration of Saengshik and increment of longitudingal bone growth. Therefore, as the result of this study, it could be expected that the administration of Saengshik for 12 weeks is helpful to the increase of longitudinal growth and growth factors in rats. Furthermore, we propose that the consumption of Saengshik as dietary supplementation may promote to increase in longitudinal bone growth in growing children.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.311-317
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• 2007

The purpose of this study is to evaluate the nutrient intake and selected blood parameters of adults with metabolic syndrome (MS) and to provide data in forming a dietary guideline for the prevention of chronic diseases. Subjects were recruited and divided into two groups according to the NCEP-ATP III criteria and WHO Asia-Pacific Area criteria for obesity. MS group was defined as subjects who have three or more risk factors and control group was defined as those with two or less of the risk factors. The average age, height, weight, body mass index (BMI) were 58.8 years, 158.0 cm, 66.3 kg, $26.5\;kg/m^{2}$, respectively, in the MS group; and 58.4 years, 158.9 cm, 59.6 kg, $23.5\;kg/m^{2}$, respectively, in the control group. The weight and BMI in the MS group were significantly higher than those in the control (p<0.001). There was no significant difference in the food and nutrient intake between the MS and control group. Male subjects in the MS group showed significantly higher intake of mushrooms than those in the control (p<0.05). Egg consumption in the MS group was significantly lower than those in the control (p<0.01). Consumption of vegetables and fiber was significantly lower for female subjects in the MS group than those in the control (p<0.05). Serum GPT, AI and WBC count in the MS group (27.8 IU/L, 3.7, $5964.2\;{\mu}/L$) were significantly higher than those in the control (22.6 IU/L, 3.2, $5250.0\;{\mu}/L$; p<0.01, p<0.001, p<0.01). In conclusion, consuming fiber and vegetables may prevent and reduce metabolic syndrome in adult men and women, and this study demonstrates the need for proper dietary management for them.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.318-326
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• 2007

The purpose for this study was to investigate the health status according to the age and BMI by interviewing male workers in their twenties and thirties in the Daegu Gyeongbuk region. The body measurement was assessed by height, weight, BMI, body circumference (waist, hip), waist-hip ratio and body fat mass. The health status has been analyzed and assessed as normal group, health concerned group and health suspected groups. Weight, percent ideal body weight (PIBW), BMI and body circumference (waist, hip) and waist-hip ratio was proven higher according to the order of obese group, overweight group and normal group. Waist-hip ratio was proved to be higher in the thirties group than the twenties. Body fat mass was higher in the obese, overweight and normal groups. In the concerns of health status, the ratio of health concerned group and health suspected group increased according to the increase of BMI. Blood pressure (SBP, DBP) was higher in the obese group than in the normal group and overweight groups, and blood glucose was higher in the thirties than in the twenties. SGOT, SGPT, ${\gamma}-GTP$ has been proven higher in the obese group than in the normal group and overweight group, ${\gamma}-GTP$ was higher in the thirties than in the twenties. Investigating the correlation of the anthropometric characteristics and biochemical characteristics, the heavy weight resulted in heavier BMI, PIBW, body circumference (waist, hip), waist-hip ratio and higher body fat mass. Blood pressure (SBP, DBP), total cholesterol, blood glucose, SGOT, SGPT and ${\gamma}-GTP$ all became higher according to these influences. In conclusion, male workers have to recognize that health status becomes worse and possibilities of chronic disease prevalence rate increases according to aging and the increase of BMI. Accordingly, it is necessary to make an effort to prevent chronic diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.276-283
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• 2007

This study was carried out to investigate the effect of isoflavone on the atherogenic effect in C57BL/6 mice. C57BL/6 female mice, 5 weeks of age, were fed on chow diets for 2 weeks during adjustment period. Mice weighing approximately $17.9{\pm}0.9\;g$ were divided into 4 groups and were fed on the experimental diets containing isoflavone for 8 weeks. Experimental groups were control (atherogenic diet), IF-10 (atherogenic diet with isoflavone 10 mg/100 g diet), IF-40 (atherogenic diet with isoflavone 40 mg/100 g diet) and IF-100 (atherogenic diet with isoflavone 100 mg/100 g diet). Food efficiency ratio was not different among the experimental groups. Plasma triglyceride (TG) concentrations were lower after 4 weeks in isoflavone supplementation groups than in control group, whereas monocyte chemoattractant protein-1 and thiobarbituric acid reactive substances (TBARS) levels of plasma were significantly (p<0.05) decreased in the isoflavone supplementation groups in a dose dependent manner. Both hepatic TG and cholesterol levels were significantly lowered in IF-100 than control. Hepatic glutathione concentrations were higher in the IF-100 group than in the other groups. Hepatic antioxidant enzyme activities including glutathione-reductase, glutathione-peroxidase, catalase, and Mn-superoxide dismutase were significantly higher in the isoflavone supplemen-tation groups in a dose dependent manner. From the above results, it is concluded that isoflavone may reduce the risk of atherosclerosis via hypolipidemic, anti-oxidative and anti-inflammatory effects.