• Reproductive and Developmental Biology
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• v.34 no.3
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• pp.271-274
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• 2010

This study was conducted to investigate the survival rate of frozen-thawed spermatozoa in equine by glycerol concentration and freezing speed Two stallions (1 Thoroughbred-13 year old and 1 Arab-7 year old) bred in Korea Racing authority was examined for 1 times in a couple of weeks. Semen was collected by condom method standing heated mare and were centrifuged 650 g for 15 min. and isolated the seminal plasma. Thick fraction of semen was diluted EDTA-Lactose-egg yolk diluents to 1:1 and contained in 0.5 ml straw as $6{\sim}14{\times}10^7\;cells/ml$. Final concentrations of glycerol were 3, 5 and 7% in cryopreseved diluents and added 4 times for 2 hours equilibration. For the freezing, equilibrated straws were located 3 or 5 em above $LN_2$ gas for 5 or 10 min. Survival rates of pre-frozen sperm were $65.0{\pm}13.2%$, $68.3{\pm}10.4%$, $66.7{\pm}11.5%$ and post-frozen were $53.3{\pm}23.1%$, $45.0{\pm}15.0%$, $50.0{\pm}18.0%$ in 3, 5, 7% glycerol concentration, respectively. There was no difference between glycerol concentrations. Survival rates of frozen-thawed sperm on freezing speed were $36.7{\pm}10.4%$, $40.0{\pm}7.1%$, $30.0{\pm}13.2%$ at 3 cm-5 min and $33.3{\pm}11.5%$, $31.7{\pm}2.9%$, $21.7{\pm}10.4%$ at 3 cm-10 min in 3, 5, 7% glycerol concentration, respectively. Survival rates of frozen-thawed sperm on freezing speed were $43.3{\pm}15.3%$, $32.0{\pm}17.9%$, $22.3{\pm}15.7%$ at 5cm-5 min and were $47.5{\pm}15.0%$, $43.3{\pm}12.6%$, $48.3{\pm}15.3%$ at 5cm-10 min in 3, 5, 7% glycerol concentration, respectively. There were significantly different between groups (p<0.05). These results suggest that glycerol concentration did not affect cryopreservation of stallion semen within 3~7% but freezing speed affects. In our experiment, the best cryopreservation condition was at 5 cm above $LN_2$ gas for 10 min for pre-freezing and 7% of glycerol concentration. These results lead to commercial AI with frozen-thawed stallion semen.

• Journal of Wetlands Research
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• v.14 no.1
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• pp.121-130
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• 2012

This study is to investigate the removal rates of nutrient in water, the biomass of water plants, and the total amounts of T-N and T-P uptakes by water plants to evaluate the ecological characteristics of the constructed wetland for treatment of livestock wastewater in Yangji-ri, Nonsan-si from June through November 2011. During the experimental period, the monthly plant biomass of constructed wetland in July were the highest as 669.4 kg, while the lowest in November as 200.1 kg. The research showed that the average nitrogen and phosphorus contents in aboveground and underground biomass of Phragmites australis were $21.9{\pm}0.6{\sim}32.1{\pm}1.5mg/g$, $15.1{\pm}5.5{\sim}24.9{\pm}5.7mg/g$, $1.5{\pm}0.3{\sim}2.4{\pm}0.2mg/g$ and $1.6{\pm}0.6{\sim}2.5{\pm}0.6mg/g$, respectively. The maximum amount of T-N and T-P uptake by Phragmites australis were 28.0 kg in July and 2.5 kg in June, respectively, while the minimum amount of T-N and T-P uptake by Phragmites australis were 9.7 kg and 0.7 kg in November, respectively. The removal rates of T-N and T-P in constructed wetland for treating livestock wastewater were 23.0 % and 59.1 %, respectively. The results of this study is expected to deduce the circulation of contaminants and nutrient in the wetland afterwards.

• Journal of Korean Society for Atmospheric Environment
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• v.22 no.5
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• pp.554-563
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• 2006

Numerous epidemiological studies have shown stronger associations between $PM_{2.5}$ and both mortality and morbidity than $PM_{10}$. The association of $PM_{2.5}$ with respiratory mortality was examined in Seoul, during the period of $1996{\sim}2002$. Because $PM_{2.5}$ data were available for only 10% of this time period, a prediction regression model was developed to estimate $PM_{2.5}$ concentration. Death count due to respiratory-related diseases(total respiratory mortality; ICD-10, J00-J98) and death counts(cause-specific mortality) due to pneumonia(ICD-10, J12-J18), COPD(ICD-10, J40-J44) and asthma(ICD-10, J45-J46) were considered in this study. Averaged daily mortality was 5.6 for total respiratory mortality and 1.1 to 1.6 for cause-specific mortality. Generalized additive Poisson models controlling for confounders were used to evaluate the acute effects of particle exposures on total respiratory mortality and cause-specific mortality. An IQR increase in 5-day moving average of $PM_{2.5}(22.6{\mu}g/m^3)$ was associated with an 8.2%(95% CI: 4.5 to 12.1%) increase in total respiratory mortality The association of $PM_{2.5}$ was stronger for the elderly ($\geq$65 years old, 10.1%, 95% CI: 5.8 to 14.5%) and for males(8.9%, 95% CI: 2.1 to 11.3%). A $10{\mu}g/m^3$ increase in 5-day moving average of $PM_{2.5}$ was strongly associated with total respiratory mortality in winter(9.5%, 95% CI: 6.6 to 12.4%), followed by spring(3.1%, 95% CI: -1.2 to 7.5%), which was a different pattern with the finding in North American cities. However, our results are generally consistent with those observed in recent epidemiological studies, and suggest that $PM_{2.5}$ has a stronger effect on respiratory mortality in Seoul.

• The Journal of Korean Society for Radiation Therapy
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• v.19 no.2
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• pp.83-90
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• 2007

Purpose: In this study, it was investigated whether commercially produced beer is able to prevent a lymphocyte from radiation induced apoptosis. Materials and Methods: Whole blood samples were acquired from 5 healthy volunteers (male, 26$\sim$38 years old) and the lymphocyte were isolated by density gradient centrifugation. Radiation induced apoptosis of the lymphocyte were investigated by 0.5 Gy, 1.0 Gy, 2.0 Gy, 3.0 Gy to 5.0 Gy irradiation. In some experiments, the donor drunk beer and then blood samples were collected. In other experiments, melatonin or glycine betain was added to lymphocyte culture medium. Treated or untreated lymphocytes were cultured for 60 hours and radiation induced apoptosis of the lymphocyte was analyzed by annexin-V staining through flow cytometery. Results: Relative radiation induced apoptosis ratio of the untreated lymphocytes is 1.22$\pm$1.1, 1.22$\pm$1.1, 1.38$\pm$1.0, 1.47$\pm$1.1, 1.50$\pm$1.2 by radiation dose of 0.5 Gy, 1.0 Gy, 2.0 Gy, 3.0 Gy and 5.0 Gy respectively. Relative radiation induced apoptosis ratio of lymphocytes is isolated from beer drunken donors is 0.97$\pm$1.0, 0.99$\pm$1.0, 1.11$\pm$0.9, 1.29$\pm$1.1, 1.15$\pm$1.1 by radiation doses respectively which are reduced 21.5% compared with untreated lymphocyte. Relative radiation induced apoptosis ratio of the lymphocytes is isolated from non-alcohol beer drunken donors is 1.22$\pm$1.1, 1.17$\pm$1.1, 1.13$\pm$1.3, 1.38$\pm$1.2, 1.32$\pm$1.1 by radiation dose of 0.5 Gy, 1.0 Gy, 2.0 Gy, 3.0 Gy and 5.0 Gy respectively which are reduced 10.8% compared with the untreated lymphocyte. Conclusion: As a result, it is suggested that beer may protect the lymphocyte from radiation damage and inhibit apoptosis.

• Journal of the Korean earth science society
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• v.26 no.6
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• pp.573-583
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• 2005

[ $PM_{10}\;and\;PM_{2.5}$ ] aerosols were collected at Busan from March, 2004 to December, 2004, and the concentrations of some metal elements were chemically analyzed to study their characteristics. The mean concentration of $PM_{10}$ was $58.2{\mu}g/m^3$ with a range of 8.3 to $161.1{\mu}g/m^3$. The mean concentration of $PM_{2.5}$ was $29.3{\mu}g/m^3$ with a range of 2.8 to $65.3\mu}g/m^3$. The mean mass concentrations of Asian dust and non Asian dust in $PM_{10}$ were $121.5\mu}g/m^3$ and $56.0{\mu}g/,^3$ respectively. The mean values of crustal enrichment factors for six elements (Cd, Cr, Cu, Ni, Pb and Zn) were all higher than 10, possibly suggesting the influence of anthropogenic sources. The crustal enrichment factors of some heavy metal elements in non-Asian dust (NAD) were higher than those in Asian dust (AD), possibly due to anthropogenic emissions transported from industries around this area by westerly wind. The soil contribution ratios for $PM_{10}$ and $PM_{2.5}$ were $15.2\%$ and $17.5\%$ on the whole. and those of AD/NAD for $PM_{10}$ and $PM_{2.5}$ were 1.9 and 2.1, respectively.

• Korean journal of applied entomology
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• v.19 no.2 s.43
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• pp.85-89
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• 1980

This experiment was carried out to investigate the life history of the Three spotted plusia (Chrysodeixis agnata Staudinger) in the laboratory in 1976. (1) Female deposited $1202{\pm}150.6$ eggs during the oviposition period which was $13.3{\pm}1.2$ days. (2) Especially, larvae were distinguished with 5-instar type and 6-instar type. The egg period was 2 days and adult longevity was $21.29{\pm}3.15$ days for female and $19.14{\pm}2.47$ days for male. Larval period and pupal period were $15.36{\pm}1.59,\;7.82{\pm}1.01$ days for the 5-instar type and $16.92{\pm}1.08,\;8.23{\pm}1.09$ days for the 6-instar type. (3) Width of head capsule of the 5-instar type was $2.77\~2189mm$ and this of the 6-instar type was $2.78\~22.38mm$. (4) A highly significant correlation was recognized between the log-width of head capsule and the number of instar.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.6
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• pp.716-723
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• 1993

This study was carried out to estimate intake level of Pb, Fe, Cu in rural area of Korea(12 males and 18 females). Analyses for the nutritional status of the record, duplicated diet collections, 24-hour urine collections, and venous blood sampling before measuring of blood pressure. The mean age and blood pressure of the subjects were 45.8$\pm$11.1years and 117.5$\pm$22.2/80.8$\pm$15.6mmHe in males, and 41.9$\pm$11.0years, 110.0$\pm$ 11.9/73.9$\pm$8.5mmHg in females, respectively. In respect to both males and females, mean BMI were 22.0$\pm$2.3, 23.1$\pm$3.0, mean Rohrer index were 131.8$\pm$14.8, 142.4$\pm$20.2 and mean skinfold thickness were 12.4$\pm$5.9mm, 25.3$\pm$7.4mm, respectively. The daily mean intakes of Pb, Fe, and Cu estimated for 3 days were 277.2$\pm$111.2$\mu\textrm{g}$/day, 12.7$\mu\textrm{g}$ 7.6mg/day, and 3.0$\pm$1.4mg/day in males and 192.0$\pm$72.4$\mu\textrm{g}$/day, 13.3$\pm$5.8mg/day, and 3.7 $\pm$1.7mg/day in females, respectively. The mean concentrations of serum Pb, Fe, Cu were 11.0$\pm$2.0$\mu\textrm{g}$/dl, 131.1$\pm$42.6$\mu\textrm{g}$/dl, 120.3$\pm$25.7$\mu\textrm{g}$/dl in males and 9.0$\pm$1.2$\mu\textrm{g}$/dl, 112.2$\pm$ 35.9$\mu\textrm{g}$/dl, 117.3$\pm$17.9$\mu\textrm{g}$/dl in females, respectively. The mean levels of Hb and Hct were 15.1$\pm$1.1g/dl, 45.2$\pm$3.3% in males and 13.1$\pm$0.8g/dl, 39.8$\pm$2.6% in females, respectively. The 24-hour urinary excretions of Pb, Fe, Cu were 35.5$\pm$10.0$\mu\textrm{g}$/day, 0.16$\pm$0.12mg/day, 60.12$\pm$0.02$\mu\textrm{g}$/day in males, and 25.3$\pm$11.0$\mu\textrm{g}$/day, 0.24$\pm$0.20mg/day, 70.07$\pm$0.03$\mu\textrm{g}$/day in females, respectively. In conclusion, the Pb intake in self selected diet of this subjects was not in the level that antagonized to Fe and Cu metabolism seriously.

• Journal of Environmental Impact Assessment
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• v.27 no.5
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• pp.431-446
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• 2018

In this study, chemical characteristics of $PM_{2.5}$ samples collected in an agricultural area in Nonsan of Korea were investigated focusing on of black carbon, 3 inorganic ions and 22 trace elements. It was found that the relative error and relative standard deviation of many trace elements fell below 10%, which indicates good analytical accuracy and precision. The mean values of $PM_{2.5}$ in an agricultural area were exceeded by new Korean air quality standard of March 2018. The concentration of $PM_{2.5}$ was well correlated with those of black carbon and ions. The concentrations of trace elements were in a wide range of seven orders of a magnitude. Based on these $PM_{2.5}$ data sets, a total of 6 sources were identified using PMF (Positive Matrix Factorization; secondary aerosol (34.4%), soil/road dust (20.1%), biomass burning (16.9%), incineration/fuel combustion (13.2%), vehicle exhaust(12.2%), sea-salt (3.17%). Results of our study indicate that it is very important to control illegal burning activities in agricultural area.

• Journal of Korean Society for Atmospheric Environment
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• v.33 no.5
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• pp.515-520
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• 2017

$PM_{2.5}$ concentrations were measured using a cyclone, impactor (the U.S. Environmental Protection Agency well impactor ninety-six, WINS) and optical particle counter (OPC) at a campus site located in Yongin for the period August 2014 through March 2017. The concentrations from cyclone (Y) were generally higher than those from impactor(X); the best-fit line was Y=1.22X+5.64. The ratios of $PM_{2.5}/PM_{10}$ ranged from 0.61 to 0.66 when $PM_{2.5}$ concentrations from cyclones in selected studies were converted into those from impactors using a regression equation in this study. The slope of the best-fit line between OPC and impactor was close to 1 at 0.95, while that between OPC and cyclone was 0.72. After sampling, the flow rate in the low-volume air sampler with cyclone decreased by 3% on average, which did not have a significant effect on measured concentrations.

• Journal of Environmental Science International
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• v.31 no.7
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• pp.637-652
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• 2022

In this study, the contributions of emissions (foreign and domestic) and atmospheric physical and chemical processes to PM_2.5 concentrations were evaluated during a high PM_2.5 episode (March 24-26, 2018) observed on the Jeju Island in the spring of 2018. These analyses were performed using the community multi-scale air quality (CMAQ) modeling system using the brute-force method and integrated process rate (IPR) analysis, respectively. The contributions of domestic emissions from South Korea (41-45%) to PM_2.5 on the Jeju Island were lower than those (81-89%) of long-range transport (LRT) from China. The substantial contribution of LRT was also confirmed in conjunction with the air mass trajectory analysis, indicating that the frequency of airflow from China (58-62% of all trajectories) was higher than from other regions (28-32%) (e.g., South Korea). These results imply that compared to domestic emissions, emissions from China have a stronger impact than domestic emissions on the high PM_2.5 concentrations in the study area. From the IPR analysis, horizontal transport contributed substantially to PM_2.5 concentrations were dominant in most of the areas of the Jeju Island during the high PM_2.5 episode, while the aerosol process and vertical transport in the southern areas largely contributed to higher PM_2.5 concentrations.