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Removals of 1-Naphthol in Aqueous Solution Using Alginate Gel Beads with Entrapped Birnessites (버네사이트를 고정화한 알긴산 비드(Bir-AB)를 이용한 수용액 중 1-Naphthol의 제거)

  • Eom, Won-Suk;Lee, Doo-Hee;Shin, Hyun-Sang
    • Journal of Korean Society of Environmental Engineers
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    • v.35 no.4
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    • pp.247-256
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    • 2013
  • In this study, alginate beads containing birnessite (Bir-AB), a highly reactive oxidative catalyst for the transformation of phenolic compounds, was prepared and its 1-naphthol (1-NP) removal efficiency was investigated in a batch test. Based on scanning electron microscopy image, it can be inferred that the alginate gel cluster acts as a bridge which bind the birnessite particles together. Kinetic experiment with Bir-AB of different mixing ratios of birnessite to alginate (Bir : AG=0.25 : 1~1 : 1 w/w) indicate that pseudo-first order kinetic constants, $k(hr^{-1})$ for the 1-NP removals increased about 1.5 times when the birnessite mixing ratio was doubled. The removals of 1-NP was found to be dependent on solution pH and the pesudo-first order rate constants were increased from 0.331 $hr^{-1}$ at pH 10 to 0.661 $hr^{-1}$ at pH 4. The analysis of total organic carbon for the reaction solutions showed that a higher removal of dissolved organic carbon was achieved with Bir-AB as compared to birnessite. HPLC chromatographic analysis of the methanol extract after reaction of 1-NP with Bir-AB suggest that the reaction products could be removed through incorporation into the aliginate beads as a bound residue. Mn ions produced from the oxidative transformation of 1-NP by birnessite were also removed by sorption to Bir-AB. The Bir-AB was recovered quantitatively by simple filtration and was reused twice without significant loss of the initial reactivity.

Seasonal Variation of Cr(VI)-contaminated Groundwater Quality and the Potential for Natural Attenuation (6가 크롬 오염 지하수 수질의 계절변화와 자연저감 가능성)

  • Chon, Chul-Min;Ahn, Joo-Sung;Roh, Yul;Rhee, Sung-Keun;Seo, Hyun-Hee;Kim, Gue-Young;Koh, Dong-Chan;Son, Young-Chul;Kim, Ji-Wook
    • Economic and Environmental Geology
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    • v.41 no.6
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    • pp.645-655
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    • 2008
  • The Cr(VI) concentrations at the shallow aquifer well (MPH-0-1) of the Moonpyung groundwater monitoring station were in the range of 0.5 to 3.1 mg/L exceeding 10 to 62 times the guideline for drinking-water quality, indicating continuous contamination. However, Cr was not detected at the deep bedrock well and the other subsidiary monitoring wells except for MPH-1 and 6. Cross-correlation analyses were conducted for rainfall and groundwater level time series, resulting in the mean time of recharge after precipitation events to be 5.6 days. For rainy season, the water level was raised and the Cr(VI) concentration was several times lower than that during dry season at well MPH-0-1 well. Correlation of the Cr(VI) concentration with the groundwater-level showed that the Cr(VI) reduction was closely related with the groundwater-level rise in the well. However, the groundwater level rise during high water season induced the lateral migration of the Cr(VI)-contaminated groundwater at well MPH-4. We enriched and isolated a chromium reducing bacteria, Enterobacter aerogenes, from the Cr(VI)-contaminated groundwater in the wells MPH-0-1 and MPH-1. The bacteria may play an important role for immobilizing Cr(VI) in the Cr(VI)-contaminated groundwater. Therefore, the migration of the contaminant (Cr(VI) must has been restricted because of the natural attenuation by microbial reduction of Cr(VI) in the groundwater. This research suggests that the bioremediation of the Cr(VI)-contaminated groundwater by the indigenous bacteria may be feasible in the Cr(VI) contaminated groundwater.

Effects of Full-Fat Soybeans and Linseed as Dietary Fat Sources on In Vitro Ruminal Disappearances of Dry Matter and C18-Unsaturated Fatty Acids and Fatty Acids Profile (지방원으로 전지대두와 아마종실의 첨가가 반추위내 건물과 C18계-불포화지방산의 조성과 소실율에 미치는 영향)

  • Lee, S.H.;Choi, N.J.;Maeng, W.J.
    • Journal of Animal Science and Technology
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    • v.45 no.3
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    • pp.443-454
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    • 2003
  • This study was conducted to investigate the effects of dietary full-fat soybeans and linseed as fat sources on in vitro ruminal disappearances of dry matter and unsaturated fatty acids and fatty acids profile. The full-fat soybeans and linseed were high in linoleic acid (C18:2n-6) and $\alpha$-linolenic acid (C18:3n-3), respectively. The incubation times were 0, 3, 6, 12, 24, 48 and 72 h. After each time of incubation, medium digesta was lyophilized for analyzing its DM and fatty acids contents. DM disappearance was significantly higher in linseed treatment compared to full-fat soybeans treatment on 6 h (p<0.01), 12 h (p<0.05) and 24 h (p<0.01), but cumulative gas production was not significantly different between both treatments. Stearic acid (C18:0) content in medium digesta was increased in both soybeans and linseed as a result of complete biohydrogenation with increased incubation time and C18:0 and C18:1 contents of full-fat soybeans were significantly higher than those of linseed (p<0.05). The content of C18:2 and C18:3 in digesta of each treatment were decreased by biohydrogenation as incubation time was increased. The content of C18:2 in full-fat soybeans was significantly higher than that of linseed (p<0.05) while the content of C18:3 in linseed was significantly higher than that of full-fat soybeans (p<0.001). Net C18:0 production was significantly higher in full-fat soybeans (332.24%) than linseed (133.16%) on 72 h. Disappearance of C18:1 was significantly lower in full-fat soybeans than linseed (p<0.05), especially full-fat soybeans showed negative (-) values on 3, 6, 12 and 24 h. The disappearance of C18:3 was significantly higher in linseed than full-fat soybeans (p<0.05). The disappearance of C18-unsaturated fatty acid was significantly higher in linseed than full-fat soybeans. In conclusion, polyunsaturated fatty acid (PUFA) in both full-fat soybeans and linseed were extensively biohydrogenated. In addition, biohydrogenation of PUFA was more completed to C18:0 in full-fat soybeans than linseed, reflecting dietary PUFA composition.

The Residue Property of Fungicide Dimethomorph and Pyraclostrobin in Green Onion under Greenhouse Condition (시설재배 쪽파에서 살균제 Dimethomorph와 Pyraclostrobin의 잔류특성)

  • Park, Jong-Woo;Kim, Tae-Hwa;Chae, Seok;Sim, Jae-Ryoung;Bae, Byung-Jin;Lee, Hae-Kuen;Son, Kyeong-Ae;Im, Geon-Jae;Kim, Jin-Bae;Kim, Jang-Eok
    • The Korean Journal of Pesticide Science
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    • v.16 no.4
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    • pp.328-335
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    • 2012
  • In order to use in the classification of minor crop for the mutual application of safe use guideline, it was investigated the residue property of fungicide dimethomorph and pyraclostrobin in green onion, a stem-crop. After pesticides were applied 2 times with 1 week interval in that day of harvest, 3 days, 7 days, 10 days and 14 days before harvest, a green onion was harvested. The residue of dimethomorph in a green onion was 26.31 and 39.08 mg/kg in that day of harvest, however, in according to elapse time, it was reduced to 6.86 and 9.34 mg/kg in 14 days before harvest. In case of pyraclostrobin, it was also reduced from 13.46 and 39.08 mg/kg to 3.57 and 5.21 mg/kg. Based on the residue in that day of harvest, the deposit of spray solution in a green onion was calculated. The deposit of spray solution of dimethomorph was 274.35~345.84 mL/kg, in case of pyraclostrobin, it was calculated 213.65~343.33 mL/kg. When the amount of the deposit of both pesticides was compared in a green onion, it was so similar. On the other hand, it was estimated the predicted dissipation curve of pesticides in the green onion during cultivation. The half-life of dimethomorph was 6.95~7.45 days, in case of pyraclostrobin, 7.15~7.45 days. When both pesticides were compared with the residue property, the deposit of spray solution and half-life of dissipation were so similar.

Comparision of the Residue Property of Insecticide Bifenthrin and Chlorfenapyr in Green Onion and Scallion under Greenhouse Condition (시설재배 쪽파와 부추에서 살충제 Bifenthrin과 Chlorfenapyr의 잔류특성 비교)

  • Park, Jong-Woo;Son, Kyeong-Ae;Kim, Tae-Hwa;Chae, Seok;Sim, Jae-Ryoung;Bae, Byung-Jin;Lee, Hae-Kuen;Im, Geon-Jae;Kim, Jin-Bae;Kim, Jang-Eok
    • The Korean Journal of Pesticide Science
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    • v.16 no.4
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    • pp.294-301
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    • 2012
  • In order to use in the classification of minor crop for the mutual application of safe use guideline, it was compared a green onion with a scallion on the residue property of insecticide bifenthrin and chlorfenapyr. After pesticides were applied 2 times with 1 week interval in that day of harvest, 3 days, 7 days, 10 days and 14 days before harvest, vegetables were harvested, and the residue of pesticides was investigated. Base on the residue in that day of harvest, the deposit of spray solution in vegetables was calculated. The deposit of spray solution of bifenthrin was 123.0 mL/kg in a green onion, and 74 mL/kg in a scallion. In case of chlorfenapyr, it was calculated 126.5 mL/kg in a green onion, and 70.0 mL/kg in a scallion. When the amount of the deposit of both pesticides was compared a green onion with a scallion, it was higher in a green onion. On the other hand, it was estimated the predicted dissipation curve of pesticides in a green onion and a scallion during cultivation. The dissipation curve of bifenthrin was y = 1.0334 $e^{-0.0602x}$ ($R^2$= 0.8606) in a green onion, and y = 0.7693 $e^{-0.1823x}$ ($R^2$= 0.9756) in a scallion. In case of chlorfenapyr, it was y = 2.2603 $e^{-0.0519x}$ ($R^2$= 0.9043) in a green onion, and y = 1.2940 $e^{-0.1051x}$ ($R^2$ = 0.9782) in a scallion. The half-life of bifenthrin was 11.51 days in a green onion, and 3.80 days in a scallion, respectively. Also, it was estimated half-life in chlorfenapyr, it was 13.35 days in a green onion, and 6.59 days in a scallion, respectively. The half-life of both pesticides in a green onion was longer than in a scallion. When both vegetables were compared with the residue property, the deposit of spray solution and half-life of dissipation in a green onion were more than those in a scallion.

Survey of the Routes and Incidence of Viral Infection of Tomato and Paprika Growing in Greenhouses in Cherwon Province, Korea During 2015-2017 (2015-2017 철원군 시설재배 과채류(토마토와 파프리카)의 바이러스병 발생 현황 및 감염경로 조사)

  • Kil, HyungBae;Kang, Minji;Choi, Won-Seok;Kim, Joong-Il;Phan, Mi Sa Vo;Im, JiHui;Kim, MeeKyoung;Park, Mi-Ri
    • Research in Plant Disease
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    • v.24 no.2
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    • pp.145-152
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    • 2018
  • During 2015-2017, we surveyed the incidence of viral infections of tomato and paprika growing in greenhouses in Cherwon province, Korea. In 2015 and 2016, we collected leaves and fruits from tomato and paprika plants growing in greenhouses. We detected viruses in the samples collected using specific primer sets for Broad bean wilt virus 2 (BBWV2), Cucumber mosaic virus (CMV), Pepper mild mottle virus (PMMoV), Pepper mottle mosaic virus (PepMoV), and Tomato spotted wilt virus (TSWV). We detected PMMoV, CMV, and TSWV in the samples, and CMV and TSWV were the most prevalent. For the prevention of future viral diseases, we then surveyed the routes of infection by these viruses in tomato and paprika plants growing in greenhouses in Cherwon province in 2017. Leaf and fruit samples were collected from seedlings and crops two and four months after transplanting into greenhouses. As a result, we found that TSWV was transferred from seedlings to plants, and outbreaks of the virus occurred at the early stage of cultivation. On the other hand, we found that CMV was a virus indigenous to the soil of some towns in Cherwon province, and thus outbreaks of this virus occurred at the middle stage of cultivation.

The Relationship of the Expressions of Stress-related Markers and Their Production Performances in Korean Domestic Chicken Breed (닭의 스트레스 연관 표지인자들의 발현도와 생산능력 간의 상관 분석)

  • Park, Ji Ae;Cho, Eun Jung;Choi, Eun Sik;Hong, Yeong Ho;Choi, Yeon Ho;Sohn, Sea Hwan
    • Korean Journal of Poultry Science
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    • v.43 no.3
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    • pp.177-189
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    • 2016
  • This study was conducted to verify the relationships between the expression values of stress-related markers and their production performances in 25 strains of Korean domestic chicken breeds. For stress response markers, the amount of telomeric DNA; expression levels of heat shock protein (HSP)-70, $HSP-90{\alpha}$, and $HSP-90{\beta}$; and comet scores were analyzed. Production performances were measured by the survival rate, body weights, days at first egg laying, egg weight and hen housed egg production. The results showed that the production traits and values of stress-related markers showed significant differences between strains. In general, the stress response of pure bred chickens with heavy weights was relatively high, while that of hybrid chickens with light weights was relatively low. The correlation coefficients between telomere contents and body weights showed that there were weak negative relationships. However, the correlations of telomere content with the survival rate and egg production were weakly positive after 20 weeks old. The expression levels of HSP genes and DNA damage rate (comet scores) were positively correlated to body weight, but were negatively correlated to the survival rate and egg production. The results implied that increasing body weight was associated with increasing HSPs expression and the DNA damage rate was associated with decreasing telomere content. In addition, increasing HSPs expression and the DNA damage rate decreased the survival rate and egg production, but the relationships with the telomere content was the reverse. Correlations among the stress-related markers showed that there were significant correlation coefficients between all of the marker values. HSPs expression was negatively correlated to the telomere content, while it was positively correlated to the DNA damage rate. There was a highly negative correlation between the telomere content and DNA damage rate. In conclusion, increasing the HSP values and DNA damage rate can promote telomere reduction, which led to a decrease in disease resistance and robustness of the chicken. Thus, increasing the stress response was verified to adversely affect the laying performance and viability of chickens.

Field Tests for Assessing the Bioremediation Feasibility of a Trichloroethylene-Contaminated Aquifer (관측정 자연표류 실험을 통한 트리클로로에틸렌(Trichloroethylene) 오염 지하수의 생물학적 복원 타당성 연구)

  • Kim Young;Kim Jin-Wook;Ha Chul-Yoon;Kim Nam-Hee;Hong Kwang-Pyo;Kwon Soo-Yul;Ahn Young-Ho;Ha Joon-Su;Park Hoo-Won
    • Journal of Soil and Groundwater Environment
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    • v.10 no.3
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    • pp.38-45
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    • 2005
  • The feasibility of stimulating in situ aerobic cometabolic activity of indigenous microorganisms was investigated in a trichloroethylene (TCE)-contaminated aquifer. A series of single-well natural drift tests (SWNDTs) was conducted by injecting site groundwater amended with a bromide tracer and combinations of toluene, oxygen, nitrate, ethylene and TCE into an existing monitoring well and by sampling the same well over time. Three field tests, Push-pull Transport Test, Drift Biostimulation Test, and Drift Surrogate Activity Test, were performed in sequence. Initial rate of toluene degradation was much faster than the rate of bromide dilution resulting from natural groundwater drift, indicating stimulation of indigenous toluene-oxidizing microorganisms. Transformation of ethylene, a surrogate probing overall activity of TCE transformation, was also observed, and its transformation results in the production of ethylene oxide, suggesting that some tolueneoxidizing microorganisms stimulated may express a orthomonooxygenase enzyme. Also in situ transformation of TCE was confirmed by greater retardation of TCE than bromide after the stimulation of toluene-oxidizing microorganisms. These results indicate that, in this environment, toluene and oxygen additions stimulated the growth and aerobic cometabolic activity of indigenous microorganisms expressing orthomonooxygenase enzymes. The simple, low-cost field test method presented in this study provides an effective method for conducting rapid field assessments and pilot testing of aerobic cometabolism, which has previously hindered application of this technology to groundwater remediation.

A Study on The Effect of The Tobacco Price Raise on The Smoking Rate and Smoking Attributable Death (담배 가격인상이 흡연률과 흡연귀속사망에 미칠 영향에 대한 연구 -대도시 일부 사무직 근로자를 대상으로-)

  • Kang, Jonw-Won;Kim, Joung-Soon
    • Journal of Preventive Medicine and Public Health
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    • v.30 no.4 s.59
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    • pp.697-707
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    • 1997
  • This study was performed to estimate the quantity of the effects of tobacco price raise on the smoking rate, and the smoking attributable deaths in Korea. The data were collected by questionnaire survey from 538 male of male workers. The questionnaire contained items on age, sex, living place, status of education, smoking history, the intention to quit smoking when the tobacco price be raised. The questionnaire, were distributed to the offices of enterprises, hospitals, research centers, and public agencies and then collected. Data were analyzed by using the age specific smoking rate, relative risks of eight major smoking related diseases, vital statistics, and the population attributable risk of deaths of smoking males. On the other hand, the impact of the tobacco price raise on the population attributable risk of death due to smoking in Korea was estimated by applying the presumed smoking rate after the price raise. The results obtained were as follows: 1. The smoking rate of male white color workers in large cities was 59.5%. 2. The proportion of male smokers who has the intention to quit smoking when the tobacco price be raised was 61.5%. 3. The proportion of male smokers who has the intention to quit smoking if the price of tobacco be raised was proportional to the degree of increasing tobacco price. It is estimated that if the tobacco price were raised more than four times as now, the presumed smoking rate goes down as low as 26.7%. If the tobacco price be raised 20% each year, presumed smoking rate is 46.2%. 4. The number of attributable male death of smoking estimated by using 8 major smoking related diseases(lung cancer, laryngeal cancer, esophageal cancer, stomach cancer, pancreatic cancer, cerebrovascular disease, ischemic heart disease, chronic obstructive pulmonary disease) was 25,863 death each year. That is 20.1% of total age over 20 male deaths. 5. f the tobacco price were raised more than four times as now and all smokers who has intention to quit smoking quits smoking, 12,336 lives, or 47.7% of smoking related deaths could be saved. 6. IF the actual practice rate of quitting smoking among male smokers with intention to stop smoking when the price of tobacco be raised is 10%, 25%, or 50%, then the expected decrease of death numbers when the tobacco price were raised more than four times as now can be 1,112, 3,483, 5,796 respectively.

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Analysis of $^{99m}Tc-ECD$ Brain SPECT images in Boys and Girls ADHD using Statistical Parametric Mapping(SPM) (통계적 파라미터지도 작성법(SPM)을 이용한 남여별 ADHD환자의 뇌 SPECT 영상비교분석)

  • Park, Soung-Ock;Kwon, Soo-Il
    • Journal of radiological science and technology
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    • v.27 no.3
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    • pp.31-41
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    • 2004
  • Attention deficit hyperactivity disorder(ADHD)is one of the most common psychiatric disorders in childhood, especially school age children and persisting into adult. ADHD is affected 7.6% in our children, Korea. and persisting into $15{\sim}20%$ in adult. And it is characterized by hyperactivity, inattention and impulsivity. Brain imaging is one of way to diagnosis for ADHD. Brain imaging studies may be provide information two types - structural and functional imaging. Structural and functional images of the brain play an important role in management of neurologic and psyciatric disorders. Brain SPECT, with perfusion imaging radiopharmaceuticals is one of the appropriate test to diagnosis of neurologic and psychiatric diseases. Ther are a few studies about separated analysis between boys and girls ADHD SPECT brain images. Selection of Probability level(P-value) is very important to determind the abnormalities when analysis a data by SPM. SPM is a statistical method used for image analysis and determine statistical different between two groups-normal and ADHD. Commonly used P-value is P<0.05 in statistical analysis. The purpose of this study is to evaluation of blood flow clusters distribution, between boys and girls ADHD. The number of normal boys are 8(6-7y, average : $9.6{\pm}3.9y$) and 51(4-11y, average : $9.0{\pm}2.4$) ADHD patients, and normal girls are 4(6-12y, average : $9{\pm}2.4y$) and 13(2-13y, average $10{\pm}3.5y$) ADHD patiens. Blood flow tracer $^{99m}Tc-ethylcysteinate$ dimer(ECD) injected as rCBF agent and take blood flow images after 30 min. during sleeping by SPECT camera. The anatomical region of hyperperfusion of rCBF in boys ADHD group is posterior cingulate gyrus and hyperperfusion rate is 15.39-15.77% according to p-value. And girls ADHD group appears at posterior cerebellum, Lt. cerbral limbic lobe and Lt. Rt. cerebral temporal lobe. These areas hyperperfusion rate are 24.68-31.25%. Hypoperfusion areas in boys ADHD,s brain are Lt. cerebral insular gyrus, Lt. Rt. frontal lobe and mid-prefrontal lobe, these areas decresed blood flow as 15.21-15.64%. Girls ADHD decreased blood flow regions are Lt. cerebral insular gyrus, Lt. cerebral frontal and temporal lobe, Lt. Rt. lentiform nucleus and Lt. parietal lobe. And hypoperfusion rate is 30.57-30.85% in girls ADHD. The girls ADHD group's perfusion rate is more variable than boys. The studies about rCBF in ADHD, should be separate with boys and girls.

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