• Korean Journal of Environmental Agriculture
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• v.15 no.4
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• pp.406-418
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• 1996

Tomatoes are water logged differently 0, 5, 10 and 15 cm, according to the developing stages such as germination and seedling stage under the condition of greenhouse. Along with this, they are treated according to the time condition such as 6, 12, 24, 48 and 120 hours. The results obtained are summarized as follows. 1. The result at germination stage Remarkable germination failure was observed when tomatoes were water-logged for 25 to 27 hours in the depth of 0 to 5 cm. Plant height recovered within 24 hours regardless of the water-logging depths. In the case of leaves, the recoverable time limit became shorter gradually in accordance with the increase of the water-logging depth. The decrease of the fresh weight showed acute response in the shoot rather than the root. It recovered with the 24 hours of water logging. Significant correlation was observed in all characteristics of plant height, number of leaves, fresh weight and germination rates according to the depth of water-logging. 2. The result at seedling stage Plant height recovered within the 24 hours of water-logging in the depth of 0 cm. On the deeper level, there was significant decrease regardless of time. With regard to the number of leaves, there was recovery up to 120 hours in the depth of 0 cm, up to 24 hours in the depth of 5 cm. There was, however, significant decrease when done for more than 6 hours on the deeper level. Growth of the shoot displayed the same tendency as in plant height and number of leave. The length of the longest root could be maintained by 80% in the water-logging of 0 cm compared with control. However in depth of 5 cm or more, it could not be maintained by the 120 hours water-logging. Root activity became conspicuously diminished with the logging over 0 cm. Respiration showed conspicuous decrease by the depth of 5 cm as a turning point. On the other hand, photosynthesis became decreased linearly by the depth of water-logging. Chlorophyll content displayed gradual decrease up to 48 hours, but conspicuously decreased up to 120 hours according to the varying depth of water-logging. Dieases tended to increase according to the depth and hours of water-logging. Diseases would be prevented by dint of insecticide, but there was no effect of fertilization. Weight and number of fruit per plant displayed gradual decrease as the depth and hours of water-logging became increased. Average weight of a fruit became increased. There was no statisticaly reciprocal effects between the depth and hours of water-logging. There was significant positive correlation among all the investigated characteristics, such as traits of growth and yield.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.440-448
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• 2020

Purpose: Most of the studies in the country on earthquake-induced landslide predict the displacement of the slope. Until now, no studies have been conducted on the occurrence of landslides and damage characteristics by earthquakes. Therefore, this study was conducted to obtain basic data of landslides caused by earthquakes. Method: In order to analyze the characteristics of earthquake-causing landslides, we have collected data reported in the media over the past decade. Landslides in foreign countries were analyzed separately by cause of occurrences such as rainfall and earthquake. Landslides from abroad were analyzed according to the cause of the occurrence, and landslides caused by earthquakes were further analyzed as follows: the magnitude of an earthquake, year of occurrence, number of occurrences by continent, damage status, etc. Result: In the past 10 years, a total of 608 landslides have been reported from overseas, and the cause is the highest with 340 landslides due to rainfall. There were 70 cases of landslides caused by earthquakes, and it was analyzed as the second cause of landslides. The average magnitude for earthquakes that caused landslides was 6.5, and the minimum and maximum magnitude were 4.4 and 8.2 respectively. The earthquake-induced landslides were the most occurrence in 2011yr and 2012yr, and the continent was the most common in Asia. Also, It was analyzed that if an earthquake caused landslides, the number of casualties increased and the size of the damage increased. Conclusion: Currently, earthquakes are steadily increasing in Korea, and the possibility of strong earthquakes is also increasing. Earthquake-induced landslides are beyond human control due to natural disasters but can minimize damage through active prevention and response. It is expected that the results of this study will be used as basic data in establishing measures for earthquake landslides to reduce property and human damage in the future.

• Journal of Animal Science and Technology
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• v.51 no.3
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• pp.207-216
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• 2009

This experiment was conducted to investigate the effects of dietary supplementation of organic acid mixture on growth performance, cecal microflora, blood characteristics and immune response in broiler chicks and to prove the possibility of organic acid mixture as an alternative to antibiotics growth promotor. A total of four hundred eighty, 1-day-old male broiler chicks (Ross$\times$Ross 308) were randomly divided into 4 groups with 4 replicates of 30 birds each. The treatments were NC (free antibiotics), PC (basal diet with virginiamycin 10 ppm and salinomycin 60 ppm), 0.3% organic acid, and 0.5% organic acid. The final body weight and body weight gain were significantly higher in organic acid 0.5% than NC (P<0.05). The feed conversion ratio in all treated groups were significantly improved as compared to that of NC (P<0.05). The carcass rate and relative organs weight were not significantly difference among the groups. The relative weight and length of small intestine in PC were significantly decreased than the other groups. The numbers of cecal coliform bacteria and Salmonella in all treated groups were significantly lower than NC (P<0.05). The number of cecal lactic acid bacteria was not different among the groups. No significant differences among the groups were observed in the contents of total cholesterol, triglyceride, blood urea nitrogen (BUN), albumin, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) in blood serum. The contents of total protein and globulin in blood serum of PC and organic acid treated groups were significantly increased as compared to those of NC (P<0.05). Therefore, albumin:globulin ratio of PC and organic acid treated groups was significantly lower than NC (P<0.05). The total white blood cell (WBC), heterophil, lymphocyte, and stress indicator (heterophil:lymphocyte ratio) were not significantly different among the groups. No significant difference was observed on the expression rate of splenic cytokines mRNA in organic acid treated groups compared to the control. Consequently, supplemental organic acid mixture improved the growth performance, and influenced positive effects on the intestinal microflora by inhibiting the growth of harmful bacteria without any adverse effects on relative weights of organs and blood biochemical parameters in broiler chicks.

• Korean Journal of Clinical Laboratory Science
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• v.48 no.3
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• pp.169-175
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• 2016

Saccharin (o-benzoic sulfimide) is the first artificial and non-caloric sweetener that was first synthesized in 1879. In this study, we examined the biological activity of saccharin against various human cancer cell lines and human bone marrow-derived mesenchymal stem cells. A viability assay based on the conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) was performed to test for the cytotoxicity of saccharin about the four human cancer cell lines (H460, H157, A549 and SKOV3), one murine cancer cellline (Raw264.7), and MSCs. In order to find the differentially expressed gene in saccharin-treated MSCs against untreated MSCs, we performed annealing control primer (ACP)-based differential display reverse transcriptionp-olymerase chain reaction (DDRT-PCR). All tested cells were treated with saccharin at various concentrations (0.0, 4.8, 7.2, 9.6, 12.0, 14.4 mg/mL) for 48 hr. The number of metabolically active cancer cells decreased when treated with the saccharin at various concentrations for 48 hr as compared with the untreated cells. The decrease in cell survival was more evident with increasing concentrations of saccharin. Moreover, novel candidate genes, which were differentially expressed in MSCs in response to saccharin, were identified in 16 bands on 2% agarose gel. This revealed 16-7 up-regulated and 9 down-regulated-differentially expressed genes indicated by arrows. One of these candidate genes was a FK506-binding protein gene. The functional roles of FK506 binding proteins, with respect to the activities of stem cell proliferation, were not characterized. Further studies are required to get a better understanding of FK506-binding proteins in its roles in increasing stem cell proliferative activities from using saccharin.

• Biomedical Science Letters
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• v.4 no.1
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• pp.11-25
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• 1998

The HLA genes located in the short arm of chromosome 6 specify heterodimeric glycoproteins involved in the regulation of the immune response. Recently, in the elucidation of HLA polymorphism, serological and cellular typing methods have been replaced by DNA typing using polymerase chain reaction (PCR). The purpose of this study was to establish the HLA DNA typing methods and determine gene frequencies of HLA molecules in Koreans. PCR-SSP (sequence specific primers) and PCR-RFLP (restriction fragment length polymorphism) techniques were used for the analysis of HLA-A, -B, -C, DRBl genes and HLA-DQAl, DQBl, DPBl genes, respectively. The results of B-lymphoblastoid cells used for control experiment were consistent with the previous data identified in the 11th International Histocompatibility Workshop. Seventeen, 23, 16, 8, 16, 13 and 37 types of HLA-A, B, C, DQAl, DQBl, DPBl and DRBl alleles were found, respectively, in a total of unrelated 120 Korean individuals. The most frequent HLA alleles were $A^*$02 (27.0%), B$^*$40 (17.6%), Cw$^*$01 (19.2%), DQAl$^*$0301 (32.1%), DQBl$^*$0303 (12.9%), DPBl$^*$0501 (31.3%) and DRBl$^*$1501 (9.2%) among Koreans. This study shows that DNA typing method using PCR technique is a relatively simple, fast and practical tool for the determination of the HLA-class I and II genes. Moreover, the data of HLA gene frequencies could be useful for the Korean database before clinical applications, including organ and unrelated bone marrow transplantation, anthropological study, disease association and individual identification.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.124-125
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• 2002

Two experiments were conducted to investigate the response of chitosan supplementation in diet on the major economic traits of broiler in two different breeds. In the both experiments, the Arbor Acres and Ross breeds were used as experimental stocks and two groups were assigned in each breed. The control group birds(CON) were fed with basal diet only and the experimental group birds(EXP) were fed with basal diet added with 10.5mg chitosan/bird/day. The chitosan was supplied to birds from day-old in experiment 1 and from 15-day-old in experiment 2. In experiment 1, the mean body weight at 35-day-old were significantly(P〈0.05) heavier by 121.2 g and 243.7 g in the EXP groups than in the CON groups of Arbor Acres and Ross, respectively. Whereas, the mean body weights at 35-day-old in experiment 2 were lighter by 91.7 g and 70.2 g in the EXP groups than in the CON groups of Arbor Acres and Ross, respectively : however, the comparisons between breeds in the mean body weight at 35-day-old did not show significant difference in each other in both breeds. In the mean feed conversion ratio of Arbor Acres from 14 to 35-day old in experiment 1, it did not show significant difference between EXP and CON groups although the feed conversion ratio of the EXP group of Ross was significantly higher(P〈0.05) than the CON group. In experiment 2, the feed conversion ratios from 14 to 35-day-old did not show significant differences between the two breeds. The percentage of mean abdominal fat depositions of EXP groups in both breeds In experiment 1 were significantly(P〈0.05) higher than those of CON groups. And the percentage of mean abdominal fat deposition of Ross was significantly(P〈0.05) lower than that of Arbor Acres. In experiment 2, the percentage of mean abdominal fat depositions did not show significant difference between EXP and CON groups in both breeds. Whereas, the interaction effects between breed and experimental groups on the above economic traits did not show significant in both experiments.

• Korean Journal of Poultry Science
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• v.43 no.1
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• pp.47-54
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• 2016

The aim of this study was to investigate the expression patterns of key genes involved in lipid metabolism in response to dietary Coenzyme Q10 (CoQ10) in hens. A total of 36 forty week-old Lohmann Brown were randomly allocated into 3 groups consisting of 4 replicates of 3 birds. Laying hens were subjected to one of following treatments: Control (BD, basal diet), T1 (BD+ CoQ10 100 mg/kg diet) and T2 (BD+ micellar of CoQ10 100 mg/kg diet). Birds were fed ad libitum a basal diet or the basal diet supplemented with CoQ10 for 5 weeks. Total RNA was extracted from the liver for quantitative RT-PCR. The mRNA levels of HMG-CoA reductase(HMGCR) and sterol regulatory element-binding proteins(SREBP)2 were decreased more than 30~50% in the liver of birds fed a basal diet supplemented with CoQ10 (p<0.05). These findings suggest that dietary CoQ10 can reduce cholesterol levels by the suppression of the hepatic HMGCR and SREBP2 genes. The gene expressions of liver X receptor (LXR) and SREBP1 were down regulated due to the addition of CoQ10 to the feed (p<0.05). The homeostasis of cholesterol can be regulated by LXR and SREBP1 in cholesterol-low-conditions. The supplement of CoQ10 caused a decreased expression of lipid metabolism-related genes including $PPAR{\gamma}$, XBP1, FASN, and GLUTs in the liver of birds (p<0.05). These data suggest that CoQ10 might be used as a dietary supplement to reduce cholesterol levels and to regulate lipid homeostasis in laying hens.

• Journal of Preventive Medicine and Public Health
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• v.21 no.1 s.23
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• pp.183-194
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• 1988

This study was carried out to investigate for resistance of V. parahaemolyticus that isolated from patients of food poisoning and fish and shellfish, captured in east coast of Kyungpook province of Korea from 1985 to 1986. VP ATCC 17802 and NAG V. ATCC 6538 were used as control. In fish, shellfish and seaweed, the more temperature increased, the shorter survival time was. In case of sea-water, the more temperature rose up, the longer survival time was, particularly in $37^{\circ}C$ and $25^{\circ}C$, the strains had survived after 6 months. And in tapwater, it was sterilized in 150 mins. and survived for 11.5 days on maximum in ground water. In kimchi, at room temperature, germicidal time was shorter more than 6 times compared with that which had been kept in refrigerator. It survived for 57.1 days in milk, 49.2 mins. in yougurt. Strains had been surviving in frozen condition at $-70^{\circ}C$ even after 6 months, present study time. In resistance test in water bath at several degrees of temperature, all the strains were sterilized in 20 mins. with $60^{\circ}C$. In resistance test to driness, number of surviving strains dropped rapidly in 10-11%) water contents. In UV $2538{\AA}$, strains were sterilized in 20 mins. In resistance test to alcohol, strains had survived for 0.1-4 mins. in fermentative wine of below than 25% and distilled wine of over than 25% in alcohol concentration. The bactericidal concentration of disinfectant was 1% in phenol and 3% in cresol. In 0.1M acetic acid and 0.1M lactic acid, number of surviving colonies decreased rapidly but not in citric acid. The more NaCl concentration rose up, the lower decreasing rate of number of surviving colonies was. The strains had showed sensitive response to vancomycin, chloramphenicol, gentamicin, and resisted to carbenicillin, ampicillin and kanamycin. When one day culture strain was cultured till 25th day, resistant strains to tetracycline and cephalothin were changed to sensitive.

• Journal of Preventive Medicine and Public Health
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• v.30 no.1 s.56
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• pp.77-101
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• 1997

In September 1994, residents of Gozan-dong, Incheon City, made a petition to the government about their health problems which might be caused by previous glass fibre landfill nearby 'H' company. In february 1995, at regular academic meeting of occupational and environmental medicine, a research team of 'D' University presented that they had found glass fibres in groundwater of the area through their survey. They were suspicious of probable association between ingestion of groundwater contaminated with glass fibres and skin tumors among residents. A joint research team was formed and carried out the survey of environment concerning groundwater and its glass fibre existence, and health assessment of residents in the area and industrial workers of 'H' company during May to November, 1995. Analysis of groundwater flow system indicates that the flow lines from the glass fibre landfill pass through or terminate at the 6 houses around the landfill. This means that the groundwater of the 6 houses around the glass fibre landfill could be affected by some possible contaminants from the landfill, but the groundwater quality of the other houses was irrelevant to the landfill. The qualitative and qualitative analyses for glass fibres in 54 groundwater samples including those from the nearby 6 houses, were carried out using SEM equipped with EDS, resulting in no evidence for the presence of glass fibres in the waters. Major precipitates, formed in waters while boiling, were identified as calcium carbonates, in particulary, aragonites in needle form. The results of health assessments of 889 residents in Gozan-dong, participated in this study, showed statistically significant differences in past medical histories of skin tumor and respiratory disease between the exposed group (31 persons who inhabited in 6 houses around the landfill) and the control group, but no significant differences in past medical histories of other diseases, such as cancer mortality, current gastroscopic findings, current skin diseases and respiratory diseases, etc. Also, we could not prove any glass fibres in excised specimens of 9 skin tumors in both groups and there were no health problems possibly associated with glass fibres in employees of the 'H' company. After all, we could not authenticate the association, raised by prior investigators, between groundwater streams, assumedly contaminated with glass fibres or not, and specific disease morbidities or common disease/symptom prevalences. That is, we could not find any glass fibres in groundwater as the only exposure factor of this study hypothesis, and there were not enough certain evidences such as increasing disease prevalences, for examples, skin, respiratory and gastrointestinal diseases etc, possibly related to glass fibre exposure, in exposed group. As a matter of course, the conditions for confirming causal association, for example, strength of the association, consistency of the association, specificity of the association, temporality of the association and dose-response relationship etc, have not been satisfied. In conclusion, we were not able to certify the hypothesis that contamination of groundwater with glass fibres might cause any hazardous health effects in residents who used it for drinking.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.314-324
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• 1997

This study was conducted to investigate whether 1) photosynthetic pigments(chlorophylls and carotenoids) are formed in dodder plant(Cuscuta australis), 2) there are any characteristics in the pigment biosynthesis, compared to that of other normal plants, and 3) dodder responds to some herbicides having target site on chloroplast. 1. Chlorophyll content of dodder tendrill grown under a natural daylight was 9 times and 50 times lower than that of field bindweed stem and leaf, respectively. 2. The photosynthetic pigment contents varied in different tissues, being higher in a apical region than in a lower region of seedling or tendrill. Chlorophyll wasn't almost observed below the 4th internode from the upper. 3. Pigment contents were greatly dependent on light intensity so that there were 4 to 6 times difference among light conditions. When the shoot containning low pigment contents under natural light, was incubated in growth chamber with various light intensities, the pigment contents were increased by 3 times of initial contents at about 97${\mu}E$ $m^{-2}s^{-1}$PAR. While the change in pigment contents was not observed at above 450${\mu}E$ $m^{-2}s^{-1}$PAR 4. Exogenous supply of 5mM 5-aminolevulinic acid increased protochlorophyllide by 7 times and 1.4 times in the etiolated shoot from field bindweed rhizome and in dodder stem, respectively, showing that dodder relatively has a low response to 5-aminolevulinic acid. 5. Pigment loss was observed in the treatment of paraquat, norflurazon, oxyfluorfen and diuron, and protoporphyrin IX was accumulated by oxyfluorfen as in normal plants Based on above results, several chracteristics of pigment biosynthesis in dodder seem to be summerized as follows. Photosynthetic pigment biosynthesis in Cuscuta australis runs even in low level. The pigment contents is differentially distributed in different regions and their contents seem significantly to be controlled by light intensities. Especially, chloroplast rapidly tends to degenerate with the development of tissue. Some herbicides having target site on chloroplast induce damage to dodder stem but are unlikely to control it well in field, except paraquat, due to low chloroplast activity and parasitic mode of nutrition.