• Tuberculosis and Respiratory Diseases
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• v.52 no.1
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• pp.5-13
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• 2002

Background: DNA repair plays a crucial role in protecting the genome from cancer-causing agents. Therefore, a reduced DNA repair capacity can increase the susceptibility to cancer. The human OGG1 (hOGG1) gene encodes DNA glycosylase/apurinic lyase and excise 8-hydroxyguanine, one of the major premutagenic DNA lesions, which is produced by oxygen radical forming agents including smoking. Recently several polymorphisms in the hOGG1 gene were identified, and it is possible that these polymorphism') may affect the DNA repair capacity and thus modulate cancer susceptibility. The relationship between the codon 326 polymorphism (Ser to Cys) in the hOGG1 gene and lung cancer risk was investigated. Materials and Method: The Ser326Cys genotypes were determined using PCR-RFLP analysis in 299 primary lung cancer patients and 186 healthy controls who were frequency (case:control=3:2) matched according to age and sex. Result: The frequencies of the Ser326Cys genotypes (Ser/Ser, Ser/Cys and Cys/Cys) among cases (23.4%, 51.8%, and 24.7%, respectively) were not significantly different from those among the controls (22.6%,52.1% and 25.3%, respectively). When the analyses were stratified according to age, sex, smoking status and packyears of smoking, no significant association between this polymorphism and lung cancer risk was found. Moreover, the Ser326Cys genotype showed no apparent relationship with any of the histological types of lung cancer. Conclusion: These result suggest that the hOGG1 Ser326Cys polymorphism is not a major contributor to individual lung cancer susceptibility in Koreans.

• Food Science and Preservation
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• v.20 no.2
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• pp.250-256
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• 2013

To verify the multiplication of microorganisms on the surface of strawberries, the fate of E. coli $DH5{\alpha}::gfp$ at different temperatures, times and strawberry extract concentrations were measured. The population of E. coli $DH5{\alpha}::gfp$ rapidly increased by 7.36~7.78 log CFU/g at $25{\sim}30^{\circ}C$ for 24 hr and slowly increased by 6.49~8.49 log CFU/g at $10{\sim}20^{\circ}C$ for 48 hr. However, E. coli $DH5{\alpha}::gfp$ did not grow at $10{\sim}15^{\circ}C$ on the surface of the strawberries, regardless of the contact times with the bacterial suspension. E. coli $DH5{\alpha}::gfp$ reached 1.52~3.26 log CFU/g at $20^{\circ}C$ as the contact frequency increased from two to six times. The contact frequencies did not significantly differ. In the case of the six-time contact on the surface of the strawberry at 25 and $30^{\circ}C$, the E. coli $DH5{\alpha}::gfp$ increased by 5.17 and 5.01 log CFU/g. The effects of the strawberry extracts on the growth of E. coli $DH5{\alpha}::gfp$ showed that sterilization and non-sterilization do not affect the growth of microorganisms for 96 hr. In the minimal broth, the growth of E. coli $DH5{\alpha}::gfp$ increased by 1 log CFU/g for 96 hr. In less than 50 percent of the strawberry extracts, the growth rate of E. coli $DH5{\alpha}::gfp$ was higher than in the control and increased by 4 and 5 log CFU/g at 50 and 25 percent of strawberry extracts, respectively. Therefore, E. coli $DH5{\alpha}::gfp$ can multiply and survive on the surface of strawberries when it comes into contact with the fruit extract.

• Food Science and Preservation
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• v.24 no.1
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• pp.36-43
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• 2017

The aim of this study was to provide the quality index of salted Korean cabbage in a short-term distribution system. Salted Korean cabbages were packaged with or without 2% salt water, and then distributed in a conventional system (CVS) and a cold-chain system (CCS) for 6 h. The material temperature of samples with and without salt water gradually increased to $19.57^{\circ}C$ and $19.43^{\circ}C$ in a CVS, respectively and to $10.73^{\circ}C$ and $12.90^{\circ}C$ in a CCS, respectively. Salinity of the materials in a CCS did not change, whereas salinities of the materials in a CVS were 1.2 and 1.7 fold higher, respectively. Also, a slight increase in acidity was observed in both packaging materials in a CCS. In the case of a CVS, total aerobic bacteria and lactic acid bacteria increased to 7.62 log CFU/g and 6.77 log CFU/g in the materials with salt water, respectively, whereas the number of total aerobic bacteria and lactic acid bacteria ranged between 5.62-5.85 log CFU/g and 4.33-4.83 log CFU/g in the materials without salt water, respectively. However, significant microbial changes were not observed in a CCS as distribution time increased. CCS with salt water packaging was effective in achieving microbial control and maintaining physicochemical quality. Salinity, aerobic bacteria, and lactic acid bacteria can be useful as quality indices for a CVS, and acidity can be useful as quality index for a CCS.

• Korean Journal of Food Science and Technology
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• v.11 no.1
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• pp.1-7
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• 1979

This experiment was carried out to investigate the nutritive value of brewery's activated sludge on the performance and nutrients utilization of egg type chicken of babcock fed the different levels of sludge. The chemical composition, content of amino acids and mineral in brewery's activated sludge were also analyzed. 3,6,9 and 12% of brewery's activated sludge were supplemented with basal ration as a substituted ingredient to soybean oil meal in experimental ration. The results obtained were as follow: 1. Chemical composition analysis 1) Brewery's activated sludge had 42.50% of crude protein on the air dried basis, and had 15,69% of crude ash, and had 2,060 kcal of metabolizable energy per kg of sludge. 2) Total amino acid content of brewery's activated sludge was 42.50% and 99% crude protein of brewery's activated sludge was a true amino acid, and brewery's activated sludge contained especially more methionine and threonine that those of soybean oil meal. 3) In case of mineral content of brewery's activated sludge, phosphorus, magnesium, copper and iron were plentifully included. However, calcium content in brewery's activated sludge was very low. 2. Feeding trial 1) Body gain of chicken fed the different levels of sludge was decreased in proportion to increasing level of sludge was decreased in proportion to increasing level of sludge. However, no statistical differences were found out between treatments. 2) Diet intake of chicken fed the different levels of sludge was significantly (p<0.05) increased as the supplementation level of sludge in ration increased. 3) Feed conversion of chicken fed the different levels of sludge was high in proportion to increasing level of sludge in ration. However, there were no significant differences between treatments. 3. Digestion trial 1) Utilization of dry matter of chicken fed the different levels of sludge was decreased as the level of sludge in ration increased. However, no statistical differences were found out between treatments. 2) Utilization of crude protein of chicken fed the different levels of sludge was significantly (p<0.01) increased as the level of sludge was higher. Utilization of crude protein of control treatment and of sludge 3% treatment was higher than that of other treatments. 3) Utilization of crude ash of chicken fed the different levels of sludge was significantly (p<0.05) decreased in proportion to increasing level of sludge in ration. 4) Utilization of NFE of chicken fed the different levels of sludge was slightly decreased in proportion to increasing level of sludge in ration. However, no statistical differences were found out between treatments. Therefore according to this experiment, it may be concluded that brewery's activated sludge can be supplemented with chicken ration by $6{\sim}9%$.

• Korean Journal of Health Education and Promotion
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• v.18 no.1
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• pp.109-125
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• 2001

The purpose of this study was to provide the basic data for establishing school education environment protection measures, on the basis of comparing and analyzing the realities and students' recognition degree of the environment and hygiene around the middle and high schools located in the rural areas. These study data were investigated by the self-administered questionnaires, taking as subject the 805 students in the middle and high schools located rural areas. And the results were as follows: First, as the result of having investigated the distribution degree of harmful environment within the purification zone around schools, it was found out that students responded: within the purification zone around the middle school, there were cartoon rooms (46.2％), electronic game rooms (45.9％), and singing rooms (45.0％). within the purification zone around the high school, there were electronic game rooms (46.3％), singing rooms (42.3％), billiard halls (41.4％), PC rooms (40.1 ％), and Soju-room (35.2％). Secondly, as having analyzed student's recognition degree of the harmful environment around the school, it was found out that middle school students responded that sexual utensils-treating shops (3.74 points) were most harmful, and next corrupted bathhouses (3.52 points), and Soju-room (3.47 points), and high school students also responded relating to harmfulness in a similar sequence. Thirdly, in case of students' recognition degree of the harmful environment around the school according to general characteristics, 1) girl students had a higher ratio of recognition that the environment around the school was harmful than boy students (p〈0.001). 2) groups of students whose living standard was high had a higher ratio of recognition that the environment around the school was harmful than groups of students whose living standard was low (p〈0.05). 3) groups of students whose school was located near the park or the residential street had a higher degree of recognition that the environment around the school was harmful than groups of students whose school was located near the factory or the shopping area (p〈0.01). 4) groups of students whose school was located near the park or the residential street had a higher degree of recognition that the environment around the school was harmful than groups of students whose school was located near the amusement area or the shopping area (p〈0.05). Fourthly, 1) relating to the harmful shops where they experienced most highly the behavior of drinking and smoking, middle school students responded that they did so in the electronic game room (22.5％) and high school students did so in the singing room (31.4％), and high school students had a very high experience ratio of drinking and smoking, compared with middle school students (p〈0.001). 2) relating to the harmful shops where they could get in contact with lewd articles, both of middle school students (5.3％) and high school students (8.3％) responded that they could do so in the video room. 3) relating to the harmful shops where they experienced unsound opposite sex acquaintance, both of middle school students (5.8％) and high school students (16.6％) responded that they did so most highly in hotels, and high school students had a remarkably high experience ratio of unsound opposite sex acquaintance, compared with middle school students (p〈0.05). 4) relating to the harmful shops where they experienced violence, middle school students responded that they did so in the electronic game room (14.0％) and then in the singing room (3.7％), and high school students responded that they did so in the electronic game room (9.3％), the nightclub (4.6％), Soju-room (4.1 ％), and high school students had a remarkably high experience ratio of violence, compared with middle school students (p〈0.05). 5) relating to the harmful places where they experienced drugs both of middle school students (0.8％) and high school students (2.4％) responded that they did so in the hotels. Fifthly, when going to the harmful shops, students had the experience of being guided and regulated roughly 1 time - 2 times, and middle school students (16.4％) and high school students (16.7％) had almost similar experience ratios of being guided and regulated. Conclusively, there was a limit in controlling the environment and purification zone only by legal regulations and institutional controls, the self-control purification effort for the school and the surrounding environment was required greatly, in order to protect students from harmful environment. In addition, the constant study to establish the educational environment purification measures must be carried out.

• Korean Chemical Engineering Research
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• v.44 no.6
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• pp.588-596
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• 2006

The surface of polystyrene membrane treated by Ar, $O_2$ plasma, and the effects were observed before and after the treatment and permeability of $CO_2$, $N_2$ and selectivity of $CO_2$ relative to $N_2$ was measured using continuous flow gas permeation analyzer (GPA). The mole ratio of O over C in the surface was increased from 0 to 0.179 with Ar plasma treatment and route mean square of surface was increased from $15.86{\AA}$ to $71.64{\AA}$. Therefore the contact angle was decreased from $89.16^{\circ}$ to $18.1^{\circ}$. Thus Plasma treatments made surface of membrane tend to be highly hydrophilic. The optimum condition for the $CO_2$ permeability and ideal selectivity of the plasma treated membrane was as follows: the measurement of Ar (60 W, 2 min, $70^{\circ}C$) plasma treatment was $1.14{\times}10^{-12}[m^3(STP){\cdot}m/m^2{\cdot}sec{\cdot}atm]$ and 4.22. In the case of $O_2$ plasma treatment, the contact angle was decreased at $13.56^{\circ}$ with increase of O/C ratio ($0.189{\AA}$) and route mean square of surface ($57.10{\AA}$). The optimum condition for the $CO_2$ permeability and ideal selectivity of the plasma treated membrane was as follows: the measurement of $O_2$ (90 W, 2 min, $70^{\circ}C$) plasma treatment was $7.1{\times}10^{-12}[m^3(STP){\cdot}m/m^2{\cdot}sec{\cdot}atm]$ and 11.5. After plasma treatment, the changes of membrane surface were all subtly linked with both cross-linking and etching effects. Finally, it was confirmed that the gas permeation capacity and selectivity of the modified membrane with plasma could be improved by an appropriate control of the plasma conditions such as treatment time, the power input and sort of plasma gas.

• Journal of Genetic Medicine
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• v.8 no.2
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• pp.113-118
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• 2011

Purpose: Placental corticotropin-releasing hormone receptor type 1 (CRHR1) expression is reduced in pregnancies with abnormal placental function such as preeclampsia (PE), and the levels and/or function of CRHR1 are genetically influenced. The aim of this study was to investigate the association between the c.33+8199C>T polymorphism in the CRHR1 gene and PE in a Korean population. Materials and Methods: Using a case-control design, the association between the CRHR1 polymorphism and the risk of PE was investigated in 203 individuals with PE and 211 normotensive controls. Genotypes were determined using a SNapShot kit and an ABI Prism 3100 Genetic analyzer. Results: Genotypes and allele frequencies for the CRHR1 polymorphism did not differ between PE and normotensive pregnancies. The variant T allele was more frequent than the ancestral C allele in both of the groups and was more frequent in the controls than in the cases. In risk analysis for PE, there was not an increased risk of preeclampsia in subjects who were concomitant homozygous rare allele genotypes (CC) (OR, 0.3; P=0.15) or heterozygous rare allele genotypes (TC) (OR, 0.8; P=0.29). There were no differences in the complications of PE such as severity or preterm delivery in patients with the CRHR1 polymorphism. Conclusion: Our findings indicate that the CRHR1 polymorphism was not associated with PE in the present Korean study group.

• Korean Journal of Environmental Biology
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• v.31 no.4
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• pp.429-439
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• 2013

This study was conducted to identify the relationship between environmental factors and algal bloom, and provide information for efficient management based on the results of monitoring the environmental parameters and algal diversity in the Jundai reservoir from March 2011 to October 2013. Little change in the weather conditions was observed during the study period except for a slight decrease in rainfall. Concentration of TN and TP in the reservoir exceeded water quality standards for agriculture and significant correlation between algal growth and environmental factors was observed. Phytoplankton in Jundai reservoir included 6 classes, 40 genus, 62 species, and the phytoplankton abundance was in the range of $1.3{\times}10^4{\sim}2.8{\times}10^6$ cells $mL^{-1}$. The annual average of phytoplankton abundance and Chl-a gradually decreased as TN and TP concentrations decreased. Overall Anabaena sp., Oscillatoria sp., and Microcystis sp. were the dominant species in Jundai reservoir. As the water temperature increased, the dominant species were Anabaena sp., Microcystis sp. and Oscillatoria sp., in that order. Anabaena sp. was dominant from spring to early summer with increase in water temperature and pollutant concentrations, and high correlation with environmental factors was observed. Microcystis sp. was dominant depending on changes in the nutrient levels. In the case of Oscillatoria sp., there was no significant correlation between phytoplankton biomess and Chl-a. However, efficient management of water environment and practical control of algal bloom in small scale reservoir polluted by livestock and farm irrigation should be achieved by identification of the relationship between algal growth and environmental factors.

• Magazine of the Korean Society of Agricultural Engineers
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• v.15 no.4
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• pp.3170-3180
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• 1973

This study of the subject will review past and present irrigation development in Korea. Particular attention will be given to water pricing structure and a case study on the purpose of rational operation and management of irrigation water and organizations, and the optimum irrigation water and organizations, and the optimum irrigation water fee inorder to reduce farmers burden and to rationalize the farmland associations management so as to achieve development of the rural environment. In 1971, the reservoir of the Farmland Improvement A sociation (FIA) produced only 775 millison $m^3$ of irrigation water or 77% of planned capacity of 1,015 million $m^3$. It was caused by inefficient maintenance of irrigation facilities; for instance, about 21% of reservoirs, pumping stations and weirs in Korea have been silted by soil erosion which hinder to water production according to an ADC survey. The first Irritation Association was established in 1906, whcih was renamed the Farmland Assoeiation by the Rural Development Enouragement Law in 1970. By the end of 1971, 411,000 ha of rice paddies were under the control of 267 associations nationwide. The average water price assessed by Associations nationwide rose from 790 won per 0.1 ha. in 1966 to 1,886 won in 1971. The annual growth rate was 20%. The highest water price in 1971 was 4,773 won her 0.1 ha. and the lowest was 437 won. This range was caused by differences in debt burden, geographic conditions and management efficiency among the Associations. In 1971, the number of Associations which exceeded the average water price of 1,886 won per 0.1 ha. was 144, or 55.1% of all Association. In determination of water price, there are two principles; one is determined by production cost such as installation cost of irrigation facilities, maintenance cost, management cost and depreciation ect. For instance, the Yong San River Development project was required 33.7 billion won for total construction and maintenance cost is 3.1 billion won for repayment, maintenance and management cost per year. The project produces 590 million $m^3$ of irrigation water annually. Accordingly, the water price per $m^3$ is 5.25 won. The other principle is determined by water value in the crop products and in compared with production of irrigated paddy and non-irrigated paddy. By using this method, water value in compared with paddy rice vs. upland rice(Average of 1967-1971) was 14.15 won per $m^3$ and irrigated paddy vs. non-irrigated paddy was 2.98 won per $m^3$. In contrast the irrigation fee in average association of 1967-1971 was 1.54 won per $m^3$. Accordingly, the current national average irrigation fee(water price) is resonable compared with its water value. In this study, it is found that the ceiling of water price in terms of water value is 2.98 won per $m^3$ or 2,530 won per 0.1 ha. However, in 1971 55% of the associations were above the average of nationwide irrigation fees. which shows the need for rationalization of the Association's management. In connection with rationalization of the Association's management, this study recommends the following matters. (1) Irrigation fee must be assessed according to the amount of water consumption taking intoaccount the farmer's ability. (2) Irrigation fee should be graded according to behefits and crop patterns. (3) Training personnel in the operation and procedures of water management to save O&M costs. (4) Insolvent farmland association should be integrated into larger, sound associations in the same GUN in order to reduce farmers' water cost. (5) The maintenance and repair of existing irrigation facilities is as important as expansion of facilities. (6) Establishment of a new Union of Farmland Association is required to promoted proper maintenance and to protect the huge investment in irrigation facilities by means of technical supervision and guidance.

• Korean Journal of Agricultural and Forest Meteorology
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• v.11 no.4
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• pp.192-205
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• 2009

The unexpected wind over the Mt. Hwawang on 9 February 2009 was deadly when many spectators were watching a traditional event to burn dried grasses and the fire went out of control due to the wind. We analyzed the fatal wind based on wind flow simulations over a digitized complex terrain of the mountain with a localized heating area using a three dimensional computational fluid dynamics model, CFD_NIMR_SNU (Computational Fluid Dynamics_National Institute of Meteorological Research_Seoul National University). Three levels of fire intensity were simulated: no fire, $300^{\circ}C$ and $600^{\circ}C$ of surface temperature at the site on fire. The surface heat accelerated vertical wind speed by as much as $0.7\;m\;s^{-1}$ (for $300^{\circ}C$) and $1.1\;m\;s^{-1}$ (for $600^{\circ}C$) at the center of the fire. Turbulent kinetic energy was increased by the heat itself and by the increased mechanical force, which in turn was generated by the thermal convection. The heating together with the complex terrain and strong boundary wind induced the unexpected high wind conditions with turbulence at the mountain. The CFD_NIMR_SNU model provided valuable analysis data to understand the consequences of the fatal mountain fire. It is suggested that the place of fire was calm at the time of the fire setting due to the elevated terrain of the windward side. The suppression of wind was easily reversed when there was fire, which caused updraft of hot air by the fire and the strong boundary wind. The strong boundary wind in conjunction with the fire event caused the strong turbulence, resulting in many fire casualties. The model can be utilized in turbulence forecasting over a small area due to surface fire in conjunction with a mesoscale weather model to help fire prevention at the field.