• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.6
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• pp.791-797
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• 1999

This study was conducted in order to evaluate nutritive values of yeasts (Kluyveromyces fragilis and Candida utilis) according to growth stages (early log phase, log phase, stationary phase and death phase) and chemical treatment of their cell wall, Proximate, amino acids, fatty acids and nucleotides composition of the yeast samples was determined. Crude protein content was high in K. fragilis ($48\~59\%$) compared to C. utilis ($26\~43\%$). Crude lipid and fiber contents of the yeasts were below than $1.6\%$ and $3.3\%$, respectively. Conposition of aspartic acid, glycine, proline, leucine, Iysine and valine of K. fragilis were higher than those of C. utilis, and glutamic acid and arginine of C. utilis were higher than those of K. fragilis. Proximate and amino acids composition was not siginificantly influenced by growth stage of the yeasts. Major fatty acids of the yeasts in all growth stages were $C_{10-18}$. $C_{16-18}$ contents were relatively high in the early log or log phase and $C_{10-12}$ contents were relatively high in the stationary or death phase. However, n-3 highly unasturated fatty acids (C$\ge$20) in the all growth stages were not observed. This result indicated that these yeast strains could not be adequate as a dietary lipid source for marine fish. Composition of nucleotides and their related compounds (ATP ADP AMP, IMP and inosine) in the early log phase yeasts were lower than those in the log, stationary and death phase yeasts.

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.79-86
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• 2016

BACKGROUND: This study was initiated to quantitatively evaluate the effects of five heavy metals on the growth and P removal efficiencies of Alcaligenes sp., known as the Phosphorus Accumulating Organisms (PAOs). It was cultivated in the batch system with five heavy metals, such as Cd, Cu, Zn, Pb and Ni, added in single and binary mixtures, respectively.METHODS AND RESULTS: IC₅₀ (half of inhibition concentration of bacterial growth) and EC₅₀ (half of effective concentration of phosphorus removal Efficiencies) were used to quantitatively evaluate the effects of heavy metals on the growth and phosphorus removal Efficiencies of Alcaligenes sp. In addition, Additive Index Value (A.I.V.) method was used to evaluate the interactive effects between Alcaligenes sp. and heavy metals. As a result, as the five heavy metals were singly added to Alcaligenes sp., the greatest inhibitory effects on the growth and P removal efficiencies of each bacteria was observed in the cadmium (Cd). In the binary mixture treatments of heavy metals, the treatments of lowest IC₅₀ and EC₅₀ were the Cd + Cu treatment. Based on the IC₅₀ and EC₅₀ of the binary mixtures of heavy metals treatments, most interactive effects between the heavy metals were found to be antagonistic.CONCLUSION: Based on the results obtained from this study, it appears that they could provide the basic information about the toxic effects of the respective treatments of single and binary mixtures of heavy metals on the growth and P removal efficiencies of Alcaligenes sp. through further study about the characterization of functional proteins involved in toxic effects of heavy metals.

• The Korean Journal of Mycology
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• v.20 no.4
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• pp.337-346
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• 1992

Trichoderma spp. are an effective control agent for damping-off or other plant diseases. The interaction between. T. hamatum and Rhizoctonia solani on the rhizosphere or surface soil were examined to assess the possible roles of antibiosis or competition in the mechanisms of biological control agents as a basic research. In a proportional comparison, total bacteria, fungi, actinomycetes and Trichoderma spp were 65%, 8.8%, 25.9% and 0.28% respectively in their distribution in the soil. Among Trichoderma spp isolated, the 5 species of Trichoderma spp were indentified as T. koninggii, T. pseudokoninggii, T. aureoviridi, T. hamatum and T. viride respectively. In a mycoparasitic test, one isolate of T. hamatum strain Tr-5 showed an enzymatic ability to break fungal hyphae into piecies and infected on the R. solani hyphae showing a parasitism. Spore germination of the all isolates of Trichoderma spp showed a 1.7-7.3% of germination in natural soil conditions, but the percentage was high in sterile soil indicating all the natural soil were fungistatic on conidia of Trichoderma spp. In rhizosphere competent assay in pea plant, the antagonistic T. hamatum, T. viride, T. koninggii, T. pseudokoninggii showed a colonizing upper soil depth in rhizosphere around 1-3 cm in root zone, but the colonizing ability was much reduced along the deeper the soil depth. Propagule density was decreased in deeper the soil layer. Disease development rate treated alone with plant pathogens, Fusarium solani, Rhizoctonia solani, Cylindrocarpon destructans increased, but disease incidence rate reduced in treatment with combinations with antagonistic T. hamatum strain Tr-5.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.701-707
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• 2008

Antidiabetic effect of Korean red ginseng (RG) processed by puffing in streptozotocin (STZ)-induced diabetic (DM) rats was investigated. Five week-old SD rats were divided into four groups; normal control (NC) group, DM group, red ginseng (RG) group and puffed red ginseng (PG) group. The RG and PG groups were orally provided with RG or PG dissolved in water (500 mg/kg) respectively for seven weeks after single injection of STZ (50 mg/kg, i.v.) followed by identification of DM. NC group received saline vehicle instead of STZ. At the end of feeding of RG or PG, the changes of fasting blood glucose, serum insulin and amylase level and serum lipid profiles were evaluated. Also, oral glucose tolerance test (OGTT), comet assay and histopathological examination were performed. At 7th week, the fasting blood glucose levels of the RG and PG groups were reduced compared to the DM group by 11.54% and 20.22%, respectively. The result of OGTT did not show significant differences among DM and two red ginseng groups. While serum insulin and TG levels were predominantly improved in PG group (p<0.05), serum amylase level was increased in RG group. Alkaline comet assay for checking the oxidative damage of DNA showed that TL (tail length, ${\mu}m$) and TM (tail moment) in the blood lymphocyte of PG group significantly decreased in contrast with DM group. Histopathological results of pancreas showed that destruction of exocrine as well as endocrine might be cured by the administration of RG and PG. These results suggest that PG could exert more protection against STZ-induced toxicity than RG group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.7
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• pp.868-875
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• 2017

The aim of the present study was to investigate antioxidant nutrient intake and risk of metabolic syndrome based on stress level in rural Korean women. Subject were participants from the Multi-Rural Communities Cohort Study, which was a part of the Korean Genome and Epidemiology Study. According to scores of the Psychosocial Well-Being Index Short-Form, a total of 10,111 subjects were classified into 'low stress group (n=8,015)' from 0 to 26 points and 'high stress group (n=2,096)' above 27 points. Data were collected using self-administered questionnaires, anthropometric measurements, and blood chemical analysis. Dietary nutrient consumption was assessed by a semi-quantitative food frequency questionnaire. High stress group showed lower intake of antioxidant nutrients, such as vitamin A, vitamin C, vitamin E, folate, zinc, and carotene compared to the low stress group. Intake of fruits and vegetable was lower in the high stress group compared to the low stress group. Subjects with high stress showed higher risk of hypertension [odd ratio (OR), 95% confidence interval (CI)=1.226 (1.112~1.351)] and hypertriglyceridemia [OR, 95% CI=1.227 (1.110~1.356)] than subjects with low stress. High stress group had a significantly greater odds ratio for metabolic syndrome compared with the low stress group [OR, 95% CI=1.216 (1.101~1.342]). Thus, the present study suggests that high stress might be associated with low intake of antioxidant nutrients and high risk of metabolic syndrome in rural Korean women.

• Clean Technology
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• v.17 no.4
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• pp.306-313
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• 2011

Flux or solder is used in soldering process for manufacturing electronic parts such as printed circuit boards (PCB). After soldering process, residual flux and solder paste on the parts should be removed since their residuals could cause performance degradation or failure of parts due to their corrosion and electric leakage. Ozone depletion substances such as 1,1,1- trichloroethane (TCE) and HCFC-141b have widely been using for removal of residual flux and solder paste after soldering process In manufacturing of electronic parts until now. In this study, non-aqueous cleaning agents without flash point were developed and applied to industrial field for replacement of cleaning agents with ozone depletion. In order to develop non-aqueous cleaning agents without ethers, esters, fluoride- type solvents. And their physical properties and cleaning abilities were evaluated, and they were applied to industrial fields for cleaning of flux and solder on the PCB. And vacuum distillation apparatus were operated to determine their operating conditions and recycling yields for recycling of used cleaning agents formulated in this study. As a result of physical properties measurement of our formulated cleaning agents, they were expected to have good wetting and penetrating power since their surface tensions were relatively low as 18.0~20.4 dyne/$cm^2$ and their wetting indices are relatively large. And some cleaning agents holding fluoride-type solvents as their components did not have any flash point and they seemed to be safe in their handling and storage. The cleaning experimental results showed that some cleaning agents were better in their cleaning of flux and solder paste than 1,1,1-TCE and HCFC-141b. And industrial application results of the formulated cleaning agents for cleaning PCB indicated that they can be applicable to industry due to their good cleaning capability in comparison with HCFC-141b. The recycling experiments of the used formulated cleaning agents through a vacuum distillation apparatus also showed that their 91.9~97.5% could be recycled with its proper operating conditions.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.5
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• pp.501-508
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• 1994

This study was undertaken to get basic data for the cold-waterless transportation of live fish. The optimal cold temperature of plaice, Paralichthy olivaceus was determined by checking the changes of dissolved oxygen and ammonia in the sea water and the survival times during storage at various temperatures. After determination of optimal temperature for transportation, the changes of serum components and muscle components of live plaice were also carried out during storage at cold($5^{\circ}C$)-waterless conditions and the recovery conditions($10\%$ density at $15^{\circ}C$). At higher storage temperature, decreases in dissolved oxygen and the increases in ammonia in seawater were observed. In addition, the survival time was short at low temperature($0^{\circ}C\;and\;3^{\circ}C$). Almost all of the serum components(hemoglobin, glucose, LDH, GOT and GPT) of live plaice gradually increased during storage in cold-waterless conditions, and then those values decreased to the initial levels after $3{\sim}10hrs$ storage in conditions of recovery. The concentration of ATP in the muscle steadily decreased during storage in cold-waterless conditions. The contents of ADP and IMP seemed to be directly related to the extent of ATP breakdown. ADP and IMP thus showed a gradual increase during storage. The level of lactate in the muscles gradually increased during these storage times, also. On the other hand, the levels of those components in the muscle entirely recovered to their original levels within $3{\sim}6hrs$ storage after they were returned to conditions of recovery. The ratio of ATP to the ATP and its related compounds${ATP/(ATP+ADP+AMP+IMP){\times}100}$ in the muscle showed $45\%$ after 18hrs storage in cold-waterless conditions. Otherwise, ratios returned to their original levels within $3{\sim}6hrs$ of storage in recovery conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.619-624
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• 2011

Tea extract (TE) has been shown to have anti-tumor properties in a wide variety of experimental systems. We evaluated green tea extract (GTE) as a biochemical modulator for the antitumor activity of cisplatin and doxorubicin in the treatment of human lung cancer A549 cells. Cells were grown in RPMI-1640 medium supplemented with 10% (v/v) heat-inactivated fetal bovine serum and two antibiotics (100 units/mL penicillin and $100\;{\mu}g$/mL streptomycin). Two types of TE, epigallocatechin galate (EGCG) and GTE, were used in this experiment. The cells were seeded at $1{\times}10^4$ cells/well in the RPMI-1640 media with or without TE ($100\;{\mu}g$/mL) and then treated with different concentrations of doxorubicin ($0{\sim}14\;{\mu}g$/mL) or cisplatin ($0{\sim}35\;{\mu}g$/mL). After incubation in 5% $CO_2$ at $37^{\circ}C$ for 24 hr, cell viability was determined with a MTT assay. We used a Western blot to detect the influence of EGCG and GTE on the expression of p53 and caspase-3 genes in the A549 cells. A549 cell viability decreased to 15% with a $10\;{\mu}g$/mL concentration of cisplatin, and to 21% with a $8\;{\mu}g$/mL concentration of doxorubicin, as measured with the MTT assay. However, pre-treatment of the cells with EGCG ($100\;{\mu}g$/mL) or GTE ($100\;{\mu}g$/mL) resulted in decreased cell viability with $6\;{\mu}g$/mL of cisplatin and $4\;{\mu}g$/mL of doxorubicin. There was no apparent change in cell viability between EGCG or GTE administration in cisplatin- or doxorubicin-induced cytotoxicity in A549 cells. The levels of p53 and caspase-3 in the A549 cells increased with both EGCG and GTE treatment. We found that GTE could potentially affect cisplatin- or doxorubicin-induced cytotoxicity of A549 cells, which may be useful in the chemotreatment of cancer.

• Journal of the Korean Association of Geographic Information Studies
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• v.20 no.4
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• pp.89-101
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• 2017

Crime occurs differently based on not only place locations and building uses but also the characteristics of the people who use the place and the spatial structures of the buildings and locations. Therefore, if spatial big data, which contain spatial and regional properties, can be utilized, proper crime prevention measures can be enacted. Recently, with the advent of big data and the revolutionary intelligent information era, predictive policing has emerged as a new paradigm for police activities. Based on 7420 actual crime incidents occurring over three years in a typical provincial city, "J city," this study identified the areas in which crimes occurred and predicted risky areas. Spatial regression analysis was performed using spatial big data about only physical and environmental variables. Based on the results, using the street width, average number of building floors, building coverage ratio, the type of use of the first floor (Type II neighborhood living facility, commercial facility, pleasure use, or residential use), this study established a Crime Incident Prediction Model (CIPM) based on Bayesian probability theory. As a result, it was found that the model was suitable for crime prediction because the overlap analysis with the actual crime areas and the receiver operating characteristic curve (Roc curve), which evaluated the accuracy of the model, showed an area under the curve (AUC) value of 0.8. It was also found that a block where the commercial and entertainment facilities were concentrated, a block where the number of building floors is high, and a block where the commercial, entertainment, residential facilities are mixed are high-risk areas. This study provides a meaningful step forward to the development of a crime prediction model, unlike previous studies that explored the spatial distribution of crime and the factors influencing crime occurrence.

• Journal of the Korea Concrete Institute
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• v.23 no.6
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• pp.711-722
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• 2011

Beam-column gravity or Intermediate Moment frames subjected to unexpected large displacements are vulnerable when no seismic details are provided, which is typical. Conversely, economic efficiency of those frames is decreased if unnecessary special detailing is applied as the beam and column size becomes quite large and steel congestion is caused by joint transverse reinforcement in beam-column connections. Moderate seismic design is used in Korea for beam-column connections of buildings with structural walls, which are to be destroyed when the unexpected large earthquake occurs. Nonetheless, performance of such beamcolumn connections may be substantially improved by the addition of steel fibers. This study was conducted to investigate the effect of steel fibers in reinforced concrete exterior beam-column connections and possibility for the replacement of some joint transverse reinforcement. Ten half-scale beam-column connections with non-seismic details were tested under cyclic loads with two cycles at each drift up to 19 cycles. Main test parameters used were the volume ratio of steel fibers (0%, 1%, 1.5%) and joint transverse reinforcement amount. The test results show that maximum capacity, energy dissipation capacity, shear strength and bond condition are improved with the application of steel fibers to substitute transverse reinforcement of beam-column connections. Furthermore, several shear strength equations for exterior connections were examined, including the proposed equation for steel fiber-reinforced concrete exterior connections with non-seismic details.