• Journal of Environmental Science International
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• 제7권4호
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• pp.441-450
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• 1998

The purpose of this study is to evaluate and to predict of eutrophication in lakes by using VollenweiderGECD model and total phosphorus concentration and inflow rate which were measurded in 1993-1996. The results of study was as follows. The annual total phosphorus loading from the watershed was calculated to be 181-195tP /yr at lake Soyang, 591-680tP/yr at lake Chungju, 420-466tP/yr at lake Taechong, 229-278tP/yr at lake Andong, 103-106tP/yr at lake Hapchon, 57-59tP/yr at lake Imha, 194-244tP/yr at lake Namgang, 8386tP /yr at lake Chuam, 99-109tP /yr at lake Somjin. These are discharged, for the most parts, from population and ftshfarm facility. TP loading on the surface area at lake Soyang was 3.0lgP/$m^2$/yr, 2.82gP/$m^2$/yr, 2.84gP/$m^2$/yr, 3. 03gP/$m^2$/yr, at lake Chungju 7.91gP/$m^2$/yr, 6.87gP/$m^2$/yr, 7.38gP/$m^2$/yr, 7.l8gP/$m^2$/yr, at lake Taechong 6.7lgP/$m^2$/yr, 7.25gP/$m^2$/yr, 7.24gP/$m^2$/yr, 6.53gP/$m^2$/yr and TP loading on the surface area of Nakdong river basin, that is, lake Andong, Imha, Hapchon and Namgang were 5.39gP/$m^2$/yr, 4.47gP/$m^2$/yr, 4. 56gP/$m^2$/yr, 4.45gP/$m^2$/yr and 2.20gP/$m^2$/yr, 2.23gP/$m^2$/yr, 2.24gP/$m^2$/yr, 2.l7gP/$m^2$/yr and 4.50gP/$m^2$/ yr, 4.50gP/$m^2$/yr, 4.54gP/$m^2$/yr, 4.43gP/$m^2$/yr and 8.25gP/$m^2$/yr, 8.48gP/$m^2$/yr, 8.48gP/$m^2$/yr, 10. 39gP/$m^2$/yr respectively. Also those of lake Chuam was 2.51gP/$m^2$/yr, 2.61gP/$m^2$/yr, 2.52gP/$m^2$/yr, 2. 54gP/$m^2$/yr and TP loading on the surface area at lake Somjin was analysed 4.09gP/$m^2$/yr, 4.l0gP/$m^2$/yr, 3.98gP/$m^2$/yr,3.73gP/$m^2$/yr. The tropic states of nine lakes can be assessed as eutrophy because phosphorus loading exceeds the critical phosphorus loading by Vollenwelder-GECD model.

• Journal of Nutrition and Health
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• 제16권3호
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• pp.200-208
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• 1983

The present studies were designed to compare the effects of both dietary fat levels and P / S ratio on lipid components in plasma and tissues. Changes in plasma HDL-cholesterol, cholesterol and TG, and also in tissue cholesterol and TG were determined in young rats fed diets providing total dietary fat as 10%, 25% or 45% of calories and P / S ratio as 0.2 or 4.0. Plasma cholesterol levels were getting higher as dietary fat levels increased at P / S 0.2. Plasma cholesterol was lower in rats fed dietary fat either 25% or 45 %, each with P / S 4.0. But at 10% no change in plasma cholesterol were observed by P / S 4.0 because of a possible insufficiency of the absolute amount of PUFA. HDL-cholesterol was rather less sensitive to the modification of dietary fat level, but was reduced in rats fed diets of P / S 4.0 at either 25% or 45% fat, even though HDL-cholesterol were increased in the group of 10% with P / S 0.2. Total cholesterol per g- liver were significantly increased as dietary fat levels increased. Liver cholesterol levels were higher in rats fed diets of P / S 4.0 at higher fat levels (25% or 45%) which possibly suggested that a reduction of plasma cholesterol by high PUFA diet was not at least from a decreased synthesis of cholesterol in liver. However, in muscle no significant differences were found by feeding high P / S ratio at each levels of fat. At 10% fat level, compared to 25% or 45%, cholesterol level was lower in g-liver but higher in g- muscle. Plasma TG was decreased as more dietary fat were supplied at P / S ratio, but no consistant response obtained at low P / S ratio. TG per g-liver were reduced by feeding P / S 4.0 diet at 10% or 45% fat level but no differences were found in muscle. P / S 4.0 diet was more efficient in lowering plasma cholesterol TG and HDL-cholesterolt levels only if fat level was more than 25% of the total calories And young rats were more resistant to dietary fat modification.

• Fisheries and Aquatic Sciences
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• 제1권1호
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• pp.35-41
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• 1998

The inhibitory effect of Lactobacillus plantarum (Lb. plantarum) which is bacteriocin­producing strain against the growth of Listeria monocytogenes (L. monocytogenes) was examined in trypticase soy broth (TSB). TSB was inoculated with 104 cells/me L. monocytogenes and then with different numbers $(10^6\;10^4\;and\;10^2\;cells/ml)$ of Lb. plantarum. The mixed cultures were incubated at 37, 25 and $4^{\circ}C$. The most effective inhibition of was found at $37^{\circ}C$ and a less inhibition at $25^{\circ}C$. However, there was no significant change in the cell numbers of both L. monocytogenes and Lb. plantarum at $4^{\circ}C$. At same incubation temperature, the higher initial inoculum level of Lb. plantarum, the better inhibitory effect against L. monocytogenes. In addition, TSB was inoculated with L. monocytogenes at different initial inoculum levels of $10^6,\;10^4$ and $10^2$ cells/me and then supplemented with 0, 30, 60 and 100 AU/ml of bacteriocin produced by Lb. plantarum. The mixed cultures were incubated at 37, 25 and $4^{\circ}C$. L. monocytogenes of three different initial inoculum levels began to be inhibited in the presence of more than 60 AU/ml of bacteriocin at $37^{\circ}C$. In TSB containing more than 60 AU/me of bacteriocin and incubated at $25^{\circ}C$, L. monocytogenes decreased by 2 log-units during the period of 12 hrs incubation and thereafter remained steady. At $4^{\circ}C$, L. monocytogenes decreased by 1.5 log-units in the presence of 60 AU/ml bacteriocin during the period of 4 days incubation and dropped to the non-detectable level in TSB with 100 AU/ml bacteriocin.

• Journal of Embryo Transfer
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• 제27권1호
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• pp.51-55
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• 2012

The objective of this study was to investigate the motility and kinematics of boar sperm that while stored at 4C. The samples of fresh boar semen were place into an extender, Androhep, and stored at $4^{\circ}C$. In three of these samples, cryoprotectants were added. The sperm's motilities and kinematics were evaluated by using microscope (${\times}400$) and the viability status was evaluated by using with eosin staining method. The 5 sample groups are; Goup A:Androhep (extender), stored at $17^{\circ}C$. Group B:Androhep (extender), stored at $4^{\circ}C$. Group C:Androhep (extender), + 3% glycerol (cryoprotectant), stored at $4^{\circ}C$. Group D:Androhep (extender), + 3% DMSO (cryoprotectant), stored at $4^{\circ}C$. Group E:Androhep (extender), + 3% ethylene glycol (cryoprotectant), stored at $4^{\circ}C$. In group A, the sperm's motility was reduced. On day one the sperm's motility was ($85.7{\pm}2.3$) and day 5 the motility was ($43.9{\pm}3.3$). In group B, C and D the sperm's motility were reduced to 0 on day 5. In group E the sperm's percentage of motility decreased. On day one the sperm's motility was ($42.0{\pm}0.5$) and day 5 the motility was ($2.3{\pm}0.3$). When comparing cryoprotectant in samples of boar sperm there is a slight improvement in the results when the use of Androhep Lite (extender), + 3% ethylene glycol (cryoprotectant), stored at $4^{\circ}C$ are used. Based on these results, ethylene glycol can protect sperm from heat shock at $4^{\circ}C$, but not satisfactory level. However, it showed the possibilities of liquid semen preservation at $4^{\circ}C$ by using cryoprotectant.

• Journal of Environmental Health Sciences
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• 제33권2호
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• pp.83-91
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• 2007

This study investigated the health effects of offensive odor in residents living near the petrochemical industry complex area(PICA) and the thermoelectric power plant(TPP) by using questionnaire. Residents who felt the offensive odor were 58.3% at PICA, 50.9% at TPP and 24.4% at classical fishing and agrarian villages (CFAV)(p=0.000). People who answered that the offensive odor was sever at CFAV were 95.2% only on summer, but at PICA and TPP, were 44.1% and 57.3% on Spring, 62.4% and 68.8% on Summer, 22.0% and 31.7% on Autumn, and 21.7% and 25.7% on Winter, respectively. Average days that the odor occurred were 4.4 days/month at CFAV, but 12.0 and 9.5 days/month at PICA and TPP, respectively. People who experienced the sleep disturbance were 28.0% and 27.1% at PICA and TPP, respectively. The most frequently subjective symptoms were headache(0.953), frequently sneezing(0.825), itchy eyes(0.766), and stimulating eyes(0.709) at PICA, and headache(1.082), itchy eyes(0.931), itchy skin(0.826), and frequent sneezing(0.674) at TPP, respectively. At PICA and TPP, the occurrence rates of diseases in respondents' families were 15.4% and 15.6% for asthma, 12.4% and 9.2% for respiratory diseases, 27.8% and 31.2% for skin diseases, and 9.1% and 6.9% for nervous diseases, respectively. In conclusion, many residents who living near the PICA and TPP experienced the offensive odor during four seasons, especially high on summer, the most frequently subjective symptoms such as headache, itchy and stimulating eyes, frequently sneezing, and some diseases among their families such as asthma, respiratory diseases, skin diseases, and nervous diseases.

• Journal of Food Hygiene and Safety
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• 제3권1호
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• pp.19-26
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• 1988

Most of meat spoilage bacteria area Gram negative, which are very sensitive to freezing ; for instance , 90% of E. coli cells are killed or sub-lethally injured by freezing at -3$0^{\circ}C$, and the freeze-injury rate is dependent upon freezing rate. Since the injured bacterial cells are sensitive to selective agents, they fail to multiply in selective media. Injured bacterial cells are, however, capable of spontaneous repair at appropriate environmental and nutritional conditions . Enumeration of injured bacterial cells involves artificial induction of repair at these conditions. Cubic beef samples(3$\times$3$\times$3cm) were frozen at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$. The samples frozen at each temperature were thawed at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave . After these respective freezing an thawing treatments, the percentage of sub-lethally injured total coliforms out of total surviving ones was measured and compared. The results were as follows: 1. The interaction between freezing and thawing on injury rate was not significant. 2. The injury rates(as means of all three thawing treatments post-freezing) by freezing at -6$0^{\circ}C$, -4$0^{\circ}C$, or -18$^{\circ}C$ were 32.2$^{\circ}C$ and 19.2$^{\circ}C$ respectively . 3. The injury rates(as means of all three freezing treatments)by thawing at 4$^{\circ}C$, 2$0^{\circ}C$, or by microwave were 49.3%, 11.7% and 21.0% respectively. The highest injury rate was caused by freezing at -6$0^{\circ}C$ and subsequent thawing at 4$^{\circ}C$. However since the injury rates by freezing treatment were not significantly different, freezing at -18$^{\circ}C$ and subsequent thawing at 4$^{\circ}C$ can also be recommended , from an economic perspective.

• Food Science of Animal Resources
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• 제18권2호
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• pp.107-114
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• 1998

This study aimed for the examination of quality characteristics and safety of potassium sorbate-free meat products. Therefore, experiments were carried out on the frankfurter sausage and pressed ham, which were stored at 4 and 30$^{\circ}C$ for up to 40 days. The potassium sorbate concentrations of the frankfurter sausage and pressed ham obtained from local market ranged from 1.087 to 1.449g / kg, which were below the permitted value as prescribed in the Korean Hygienic Regulation. At the 0 day the total aerobic bacterial counts of frankfurter sausage and pressed ham were in the level of around 103.0 and 103.4 CFU / g, respectively. However, they were prominently increased after 20 days at 4$^{\circ}C$ and 10 days at 30$^{\circ}C$ to higher than 105 CFU / g. After 30 days the counts were increased to 106.5 and 107.2 CFU / g, respectively. The growth curve of lactic acid bacteria was shown to be similar with that of total bacteria. the counts of lactic acid bacteria of the products stored at 4$^{\circ}C$ were 101∼102 CFU / g lower than those stored at 30$^{\circ}C$. Coliform bacteria was not detected in both of the products stored at 4$^{\circ}C$ even after 40 days storage, but after 10 days at the 30$^{\circ}C$. No significant differences in the microbial counts examined in this study were observed between frankfurter sausage and pressed ham. The biochemical tests on the isolated colonies from Clostridein agar showed no presence of Clostridium botulinum and Clostridium perfringens in the meat products examined. The pH of frankfurter sausage and pressed ham at the beginning was about 6.6, which level was maintained relatively constant during the storage at 4$^{\circ}C$, but it was increased after decrease to about 5.5 during the storage at 30$^{\circ}C$. TBA value was increased slightly till 30 days, but after that time increased sharply. VBN value was increased slowly during the whole storage, but it was more than 30 mg% for the samples stored at 30$^{\circ}C$.

• Journal of Veterinary Clinics
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• 제17권2호
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• pp.334-339
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• 2000

The considerable researches have been done on the change,1 associated with age in the blood picture of domestic animals, but a survey has not been of the blood picture in Thoroughbred fears in Korea. Therefore, the purpose of this study is to outline the range of values in clinically not\\\\`- mal Thoroughbred foals. Some blood chemical parameters from 3 days to 8 weeks of age were exam-ined to obtain normal values in Thoroughbred foal7. Blood samples were obtained from the jugular vein in 11 Thoroughbred foals and collected at 3 days, and at 1,2,4 and 8 weeks of age, respectively. The results obtained ill this study were summarized as follows: The packed cell volume (PCV) at 4 weeks of age was significantly lower than that at 3 days of age (P<0.01) and that al 2 and 8 weeks of age were straightly lower than that at 3 days of age (P<0.05). The total protein (TP) at 8 weeks of age was higher than that at 3 days, 1 and 2 weeks of age (P<0.05). The activity of aspartate ami-notransferase (AST) at 2,4 and 8 weeks of age were significantly higher than that at 3 days of age (P<0.01). The total bilirnbin showed a tendency to decrease gradually according to the weeks and that at 2,4 and 8 weeks of age were significantly lower than that at 3 days of age (P<0.01). The BUN at 1 and 8 weeks of ago were lower than that at 3 days of age (P<0.05). The concentration of Ca at 1 week of alee was higher than that at 3 days of age (P<0.05). The vitamin A and vitamin E showed a tendency to decrease gradually from 3 days to 4 weeks of age and increased slightly at 8 weeks of age.

• Korean Journal of Materials Research
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• 제34권4호
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• pp.185-193
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• 2024

In this study, NASICON-type Li_1+XGa_XTi_2-X(PO₄)₃ (x = 0.1, 0.3 and 0.4) solid-state electrolytes for all-solid-state batteries were synthesized through the sol-gel method. In addition, the influence on the ion conductivity of solid-state electrolytes when partially substituted for Ti⁴⁺ (0.61Å) site to Ga³⁺ (0.62Å) of trivalent cations was investigated. The obtained precursor was heat treated at 450 ℃, and a single crystalline phase of Li_1+XGa_XTi_2-X(PO₄)₃ systems was obtained at a calcination temperature above 650 ℃. Additionally, the calcinated powders were pelletized and sintered at temperatures from 800 ℃ to 1,000 ℃ at 100 ℃ intervals. The synthesized powder and sintered bodies of Li_1+XGa_XTi_2-X(PO₄)₃ were characterized using TG-DTA, XRD, XPS and FE-SEM. The ionic conduction properties as solid-state electrolytes were investigated by AC impedance. As a result, Li_1+XGa_XTi_2-X(PO₄)₃ was successfully produced in all cases. However, a GaPO₄ impurity was formed due to the high sintering temperatures and high Ga content. The crystallinity of Li_1+XGa_XTi_2-X(PO₄)₃ increased with the sintering temperature as evidenced by FE-SEM observations, which demonstrated that the edges of the larger cube-shaped grains become sharper with increases in the sintering temperature. In samples with high sintering temperatures at 1,000 ℃ and high Ga content above 0.3, coarsening of grains occurred. This resulted in the formation of many grain boundaries, leading to low sinterability. These two factors, the impurity and grain boundary, have an enormous impact on the properties of Li_1+XGa_XTi_2-X(PO₄)₃. The Li_1.3Ga_0.3Ti_1.7(PO₄)₃ pellet sintered at 900 ℃ was denser than those sintered at other conditions, showing the highest total ion conductivity of 7.66 × 10^-5 S/cm at room temperature. The total activation energy of Li-ion transport for the Li_1.3Ga_0.3Ti_1.7(PO₄)₃ solid-state electrolyte was estimated to be as low as 0.36 eV. Although the Li_1+XGa_XTi_2-X(PO₄)₃ sintered at 1,000 ℃ had a relatively high apparent density, it had less total ionic conductivity due to an increase in the grain-boundary resistance with coarse grains.

• Korean Journal of Acupuncture
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• 제24권1호
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• pp.95-111
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• 2007

Objectives : This research ws performed to investigate the effect of manual acupuncture at TE4, SP3 and TE4+SP3 on body weight, blood glucose, BUN, creatinine, lipid metabolism, liver function and morphological change of hepatic tissue in hyperglycemia rats. Methods : Experimenal groups were divided into hyperglycemia group(Control group), hyperglycemia and acupuncture therapy group at SP3, hyperglycemia and acupuncture therapy group at TE4, hyperglycemia and acupuncture therapy group at TE4+SP3 , once per 2 days during 5 weeks. Results : Body weight was decreased significantly in TE4 group of fifth week compared with Control group. Blood glucose was decreased significantly in SP3 group compared with control group. Creatinine was decreased significantly in TE4 and TE4+SP3 group compared with control group. Total cholesterol was decreased significantly in TE4+SP3 group compared with control group. Triglyceride was decreased significantly in TE4 gorup compared with control group. In the morphological change of hepatic cell, TE4 and SP3 group were showed he rough endoplasmic reticulum forms aggregates of parallel, flattened cisternae scattered randomly throughout the cytoplasm compared with control gruop. Conclusions : Acupuncture at TE4 can manage hyperglycemia by controlling body weight, and lipid metabolism in hyperglycemia rats induced by streptozotocin.