• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.210-216
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• 2007

A study was conducted to find mechanism and spray characteristics of a mini-sprinkler with downward spray to develop a new design type to be able to prevent drop water. The experiments were executed in a plastic greenhouse to minimize the effect of the wind. Data was collected at five different operation pressures and at 4 different raiser heights. Spray characteristics of the sprinkler such as effective radius, effective area, mean application depth, absolute maximum application depth, effective maximum application depth and coefficient of variation were determined. In order to analyze the mechanism and packing supporter of sprinkler, the numerical simulation using ABAQUS was performed. The optimum pressure for preventing drop water was determined.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.218-229
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• 2018

The purpose of this study was to provide basic data on smartphone addiction intervention as well as college adaptation education and policy development by confirming the mediating effect of social support in relation to the effect of smartphone addiction on college life adaptation in nursing college students. The subjects of this study were 173 students who agreed to participate in this study among 4-year nursing college students in D city. The collected data were analyzed by descriptive statistics, One-way ANOVA, Pearson's Correlation, Hierarchical Multiple Regression, and Sobel test using the SPSS 23.0 statistical program. In the results, the number of subjects showing smartphone addiction was 47 in the high risk group, 29 in the potential risk group, and 97 in the general group, and the average level of adaptation to college life in the smartphone addiction group was statistically lower as the level of addiction increased. The average social support level of the smartphone addiction group was not significant. There was a negative correlation between students' adaptation to college life and smartphone addiction (r=-.34, p<.001) and a positive correlation with social support (r=.38, p<.001). Social support showed a significant negative correlation with smartphone addiction (r=-.17, p=.023). Moreover, social support was partially mediated. Based on the results of the study, it was found that social support and related college policies are needed to improve students' adaptation to college life.

• Journal of Nutrition and Health
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• v.20 no.2
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• pp.111-121
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• 1987

Lipie peroxide formation, antiperoxidative s system and body adaptability for handling lipid p peroxide were examined in the first and second g generations of rats fed fish oil. Mackerel oil(MO) was used and four other dietary oils and fat, i.e. soybean oil(SO), perilla oil(PO), rapeseed oil(RO) and beef tallow(BT) were also employed to compare the effect of fish oil. Synthetic diets containing these five dietary fats at the level of 1O%(w/w), were given to the correspond­m ing groups of male and female rats weighing about 70 grams. After 34 days of feeding, male a and female rats were mated and their offsprings were raised throughout suckling (17, 26 days) and weanling (39 days) periods. Liver lipid pero­x xide level was highest in MO group of both first (mother rats after lactation) and second genera­t tions of 17 and 26 days old, but not of 39 days old. During suckling period, liver lipid peroxide level was well matched to total unsaturation of dietary fat. Brain lipid peroxide levels were not different among five groups. Liver $alpha$-tocopherol a and reduced glutathione (GSH) levels were lowest in MO fed first generation. In second generation, $alpha$-tocopherol level was also low in MO group, although the effect was less pronoun­c ced, but GSH level was not different from other groups. Oxidized glutathione (GSSG) level did not consistently vary by change in dietary fat. Glutathione peroxidase activity increased as young rats grew up to 39 days. Superoxide d dismutase activity change was insignificant by a age, but was shown as lowest in MO group. At the age of 26 and 39 days, liver glutatione peroxidase activity was increased as was level of lipid peroxide, suggesting that this is the one of the mechanisms responsible for body adapta­b bility for protection against the accumulation of lipid peroxide.

• Journal of Nutrition and Health
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• v.46 no.1
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• pp.5-14
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• 2013

The anti-obesity effects of fermented black bean were tested with mice fed a high fat diet for seven weeks. Body weight gain and feed efficiency ratio (FER) in the high fat diet control (HC) group were markedly higher, compared with those of the normal control (NC) group, but were significantly lower in the 2% black bean powder supplemented high fat diet (BB) group and 2% black bean powder fermented by M. pilosus supplemented high fat diet (BBM) group, compared with those of the HC group. Food intake in the HC and BB groups was significantly lower than that of the NC and BBM groups. Water intake in the HC group was significantly lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. On the other hand, relative liver and kidney weight in the HC group was lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. In addition, whereas epididymal fat weight in the HC group was markedly higher than that of the NC group, it was significantly lower in the BB and BBM groups, compared with that of the HC group. Meanwhile, hepatic GSH in the HC group was significantly lower than that of the NC group, but was slightly higher in the BB and BBM groups, compared with that of the HC group. Although hepatic LPO in the HC group was dramatically higher than that of the NC group, it was significantly lower in the BB and BBM groups, compared with that of the HC group. In addition, serum TG, total cholesterol, and LDL-cholesterol in the HC group was significantly higher than that of the NC group, but was significantly lower in the BB and BBM groups, compared with that of the HC group. On the contrary, HDL-cholesterol in the HC group was significantly lower than that of the NC group, but was higher in the BB and BBM groups, compared with that of the HC group. In addition, activity of XOR D type in the HC group was lower than that of the NC group, but was slightly higher in the BB and BBM groups, compared with that of the NC group. Activities of ROS scavenging enzymes, such as SOD, GPX, and GST in the HC group were significantly lower than those of the NC group, but were significantly higher in the BB and BBM groups, compared with those of the HC group. In addition, serum ALT activity in the HC and BB groups was higher than that of the NC group, but was significantly lower in the BB and BBM groups, compared with that of the HC group. In histopathological findings, hepatic fat accumulation in the HC group was higher than that of the NC group, but was lower in the BBM group, compared with that of the HC and BB groups. In particular, antiobese, hypolipidemic, and antifatty liver effect of black bean powder fermented by M. pilosus was specifically higher than that of non-fermented steamed black bean. In conclusion, the constituents of black bean fermented by Monascus pilosus have been proven to not only inhibit obesity and hyperlipidemia but also decrease hepatic fat accumulation in high fat diet-induced obese mice.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.359-369
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• 2011

Twelve species of food microalgae were investigated to clarify the digestion index of Crassostrea gigas larvae using epifluorescence microscopy to choose an appropriate diet for artificial seed production in hatchery. An experiment was conducted using 1 (D shaped stage), 4 (Early umbo stage), 8 (umbo stage) and 12 (Full grown stage) days old larvae. larvae were stocked in 1 L flasks at 5 individuals/mL and fed $10{\times}10^4$ algal cells/mL of each species individually. Prior to larvae were fed for 3 h and then were observed under the microscope to detect ingestion; larvae were then sieved and replaced in 1 L flasks containing filtered seawater and were observed after 3, 5 and 8 h to analyse the digestion index. Values of digestion indices were specific for each alga. No evidence for the ingestion of Thalassiosira weissflogii was evident at all larval development stages tested. Digestion indices of others microalgae were 0.8-99.7% at 4 stage of larval development stages: Chlorella ellipsoidea (0.8-5.4%), Nannochloris oculata (1.4-5.0%), Isochrysis galbana (99.1-99.5%), Pavlova lutheri (99.1-99.5%), I. aff. galbana (99.4-99.5%), Cheatoceros calcitrans (0.0-99.2%), C. gracilis (0.0-99.7%), C. simplex (0.0-95.9%), Phaeodactylum tricornutum (0.0-99.6%), Tetraselmis tetrathele (0.0-99.7%) and Dunaliella tertiolecta (0.0-99.6%), respectively. Therefore, it is assumed that food microalgae showing the high digestion such as I. galbana should be supplied to the early umbo stage larvae, and then after the umbo larval stage, the mixed microalgae with diatoms and light green algae should be supplied to the full grown stage larvae to increase the digestion of their larvae.

• Korean Journal of Psychosomatic Medicine
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• v.25 no.2
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• pp.153-165
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• 2017

Objectives : Recent neuroimaging studies focus on dysfunctions in connectivity between cognitive circuits and emotional circuits: anterior cingulate cortex that connects dorsolateral orbitofrontal cortex and prefrontal cortex to limbic system. Previous studies on pediatric depression using DTI have reported decreased neural connectivity in several brain regions, including the amygdala, anterior cingulate cortex, superior longitudinal fasciculus. We compared the neural connectivity of psychotropic drug naïve adolescent patients with a first onset of major depressive episode with healthy controls using DTI. Methods : Adolescent psychotropic drug naïve patients(n=26, 10 men, 16 women; age range, 13-18 years) who visited the Korea University Guro Hospital and were diagnosed with first onset major depressive disorder were registered. Healthy controls(n=27, 5 males, 22 females; age range, 12-17 years) were recruited. Psychiatric interviews, complete psychometrics including IQ and HAM-D, MRI including diffusion weighted image acquisition were conducted prior to antidepressant administration to the patients. Fractional anisotropy(FA), radial, mean, and axial diffusivity were estimated using DTI. FMRIB Software Library-Tract Based Spatial Statistics was used for statistical analysis. Results : We did not observe any significant difference in whole brain analysis. However, ROI analysis on right superior longitudinal fasciculus resulted in 3 clusters with significant decrease of FA in patients group. Conclusions : The patients with adolescent major depressive disorder showed statistically significant FA decrease in the DTI-based structure compared with healthy control. Therefore we suppose DTI can be used as a bio-marker in psychotropic drug-naïve adolescent patients with first onset major depressive disorder.

• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.3
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• pp.3-12
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• 2000

The field surveys and the measurements of seawater temperatures were conducted every month from 1997 to 1999, and the distributions of seawater temperature were simulated and reproduced by a three dimensional hydrodynamic numerical model over the southern waters of Cheju island. In order to estimate the marine environmental capacity for the reception of the heat loads of cooling water discharged from Hwasoon Thermal Power Plant(HTPP) in the study area, the simulations for predicting the situation of unfavorable environment in which marine organisms might not be satisfied with change in seawater temperature were peformed using a three dimensional hydrodynamic numerical model by controlling quantitatively the heat loads of cooling water from HTPP Currently, HTPP discharges cooling water of 35.9℃ into the sea as much as 112,800m³/day in summer. As the results of simulations, the more the heat loads from the power plant increase, the more increase the seawater temperatures around the water areas adjacent to the power plant. In case the heat loads of cooling water from HTPP become about 5 times as high as the present loads, seawater temperatures at near-shore waters adjacent to HTPP appear to be increased to the extent of 0.5℃ above the existing seawater temperature in summer. The marine environmental capacity for the reception of thermal discharge from HTPP is estimated to be about 530×10/sup 6/kcal/day which is equivalent to the increase of a factor of 2 in the temperature of cooling water without any change in the discharge rate of cooling water or which is equivalent to the increase of a factor of 4.6 in the discharge rate of cooling water without any change in the temperature of cooling water. Comparing the case of the increase in the discharge rate of cooling water with the case of the increase in the temperature of cooling water on the basis of the same heat loads of 530×10/sup 6/kal/day, the former case is expected to increase seawater temperature a little higher and to extend the area affected by heat loads a little broader.

• The Korean Journal of Pesticide Science
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• v.17 no.2
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• pp.126-132
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• 2013

The objectives of this study were to provide the basic data of the residue of deltamethrin in the stream water. Deltamethrin was treated on side of Ban-Suk stream and Juk-Dong ditch for hygienic purpose by air spray. The drift concentration of deltamethrin was investigated with different wind speed condition on Ban-Suk stream (A), and the change of residue with time course on Juck-dong ford (B). Also we found the residual change of deltamethrin until 48 hour in Yu-Seong stream confluence (C) where two streams join. Maximum residues of A were $0.17{\mu}g/L$ (5 min, 200 m) at strong wind speed and $4.42{\mu}g/L$ (0 min, 25 m) at moderate wind speed according to different wind velocity. Residues of B were $0.15{\sim}0.26{\mu}g/L$ (0~480 min) after spraying, and decreased to a non-detected level after 720 min. Residues of C were $0.15{\mu}g/L$ (0 min), $0.11{\mu}g/L$ (1 min) and $0.10{\mu}g/L$ (12 hr) after spraying, and no residues were detected in any other samples. From these results, it is concluded that deltamethrin residues in water should be rapidly diluted into stream water and affected negligible toxic effect to stream ecosystem.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.14 no.3
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• pp.179-188
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• 1981

The authors made an investigation concerning the geographical distribution and some major differentiations in morphological characteristics associated with the each habitat, of the pond smelt, Hypomesus olidus, which was introduced into Korea more than 50 years ago. Major characteristics utilized for the comparison study were upper jaw (maxillary), number of fin rays, scale structure, vertebral count, number of pyloric caeca, number of gill rakers, and the relative measurements of these and other internal characters. 1. The main areas of natural distribution are Paro Lake, Soyang Lake, Han River, Euirim Lake, and Ogjeong Lake (or Unam Lake) and the tributaries of these waters. 2. Morphological variations varied when the mean values of measurements from each area were compared with the standard measurement value by mosaic comparison, and in some instances a significant variation was found. 3. The most significant variations were found in the number of fin rays of pectoral and anal fins; the lengths from the tip of snout to the origin of pectoral fin, from snout to ventral fin, and from snout to anal fin, relative to standard body length; eye depth relative to head length; upper jaw: the number of pyloric caeca and the scale structure. Variations, on the other hand, by each habitat were not clear in the numbers of ventral and dorsal fin rays, gill rakers, vertebrae and lateral line scale : and the depth of caudal peduncle and distance from the tip of snout to the origin of dorsal fin relative to standard body length. 4. The scales of pond smelt showed some differences in the shape of scales, the shape and position of the focus and the number of ridges according to the scale positions on the body. No radii were present. The relations between longitudinal and transverse diameters of the scale suggest that the pond smelts of Soyang Lake and Un-am Lake are closely related, and those of Han River and Euirim Lake are also closely related. 5. The geographical variations in morphology of the pond smelt seem to have resulted from the variations in turbidity, water temperature, salinity (rather conductivity) and currents. 6. From the results obtained, it may be concluded that such factors as supramaxillary, relation between scale length and its breadth, number of caudal vertebrae and eye depth relative to head length may be used as the key characters for the classification of geographical varieties of Pond smelt.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.140-148
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• 2015

Purpose: The purpose of this study was to evaluate the role of coffee in diabetic rats in order to prevent hyperglycemia and hyperlipidemia, and to improve antioxidant enzyme activity in streptozotocin induced diabetic rats. Methods: Thirty two male Sprague-Dawley rats (body weight $200{\pm}5g$) were divided into two groups; diabetic and nondiabetic groups. The groups were each randomly divided into two subgroups; fed control and coffee (5 g coffee powder/kg diet) diets. Diabetes was induced by intramuscular injection of 50 mg streptozotocin/kg body weight. Rats with blood glucose concentrations ${\geq}300mg/dL$ were considered diabetic for these experiments. All rats were fed an experimental diet and deionized water ad libitum for 4 weeks. Results: The results of this study indicate that body weight gain was significantly lower in diabetic groups than in nondiabetic groups regardless of diet. Mean food intake was significantly higher in diabetic groups than in nondiabetic groups, and significantly higher in the coffee group than in the control group in diabetic rats. Food efficiency ratio (FER) was significantly lower in diabetic groups than in nondiabetic groups regardless of diet. The fasting blood glucose of coffee supplemented groups was significantly lower compared with the control group in diabetic and nondiabetic rats. The levels of serum LDL-cholesterol and atherogenic index were significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats, and serum HDL-cholesterol was significantly higher in the coffee group than in control groups. The contents of hepatic triglyceride were significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats. The lipid peroxidation of malondialdehyde (MDA) contents was significantly lower in the coffee group than in the control group in diabetic and nondiabetic rats. Activity of superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase in liver was not significantly different by experimental diets among all groups. Conclusion: In conclusion, effects of 0.5% coffee powder supplemented diet were beneficial on blood glucose and lipids in diabetic rats.