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A study on the adsorption characteristic and safety assessment of railway subsoil material (철도 노반 재료의 중금속 흡착특성과 안전성에 관한 연구)

  • Paek, Seoungbong;Gil, Kyungik
    • Journal of Wetlands Research
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    • v.17 no.2
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    • pp.146-154
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    • 2015
  • Domestic railway industry has grown in numbers, scale of railway ndustrial and operation because was focused on an environmentally sustainable transportation. However, it is not enough to treat and prevent heavy metals which occur as the railway operation increases. The heavy metals occurred when the operating railway and it will be flow into water system with rainfall effluent during rainfall. will flow out along with the rainfall effluent when rainfall comes. In case of a railway bridge, In particular, heavy metals were flow into the water system without any treatment from railway bridges where located nearby rivers and lakes. So, rainfall effluent from railway facilities was occurred pollution of water system. For the prevent of heavy metal runoff during rainfall, the adsorptivity of material in railway roadbed is important.In this study, adsorptivity of gravel which is main gravel and blast-furnace slag were conducted adsorption test and deducted Freundlich's and Langmuir's isothermal adsorption equations. Safety as railway subbase course material was evaluated using modeling. As a result, absorption amount of slag, Cd and Cu, was shown higher than gravel and Pb along with Zn showed higher absorption amount of gravel. However, absorption amount of slag was shown higher than gravel used as railway subbase course material as time passes by. Absorption features had more suitable determination coefficient of heavy metals in warm absorption type such as Langnmuir compared to warm absorption type like Freundlich. To add, they showed less transformation by about 10% compared to gravel in safety evaluation through modeling. This is a railway subbase course material that prevents water outflow of heavy metal thus we can know slag is needed to be used.

Prevalence of Canine Retinal Diseases in Korea: 65 cases (국내 개에서 발생한 망막질환 65례)

  • Jeong, Man-Bok;Park, Shin-Ae;Kim, Won-Tae;Kim, Se-Eun;Che, Je-Min;Yi, Na-Young;Seo, Kang-Moon
    • Journal of Veterinary Clinics
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    • v.24 no.2
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    • pp.154-159
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    • 2007
  • The objective of this retrospective study was to investigate the prevalence of retinal diseases in dogs presented to the Veterinary Medical Teaching Hospital, Seoul National University from April 2004 to December 2005. Sixty-five dogs (120 eyes) with retinal diseases involving blindness were included in this study. Age, breed, and gender data for all breeds were collected from medical records documenting vision loss. Generalized progressive retinal atrophy (gPRA) was the most common manifestation. Other prevalent findings included sudden acquired retinal degeneration (SARD) and retinal detachment (RD). Bilateral gPRA was found in 32 dogs with a female-to-male ratio of 1 : 1. The mean $age{\pm}SD$ of all dogs in this group was $4.66{\pm}2.30$ years with a range of 3 to 12 years. Breeds with highest prevalence of gPRA were Miniature Schnauzer (24/32, $mean{\pm}SD$ age: $3.79{\pm}0.78$ yr) and Poodle (2/32, $6.50{\pm}0.71$ yr). Twelve dogs (24 eyes) were diagnosed with SARD bilateraly, ranging from 3 to 13 years of age ($mean{\pm}SD:\;6.91{\pm}2.61$ yr). There were no abnormalities in fundus of 11 dogs at presentation. Electroretinography (ERG) without anesthesia was performed in 7 dogs, and all response was totally extinguished. Retinal detachment was identified in 21 dogs (32 eyes): 11 bilateral and 10 unilateral (7 right eye, 3 left eye). The most common breed was Shih Tzu (15/21, $mean{\pm}SD$ age: $4.39{\pm}3.24$ yr). Four other breeds comprised the remaining 6 cases (8 eyes). The everall mean age of the group was: $4.18{\pm}2.89$ years (range 0.8 to 14 years) with a female-to-male ratio of 1 : 1.1 (10 females, and 11 males).

Studies on Effect and its Mechanism of Herbicide Mixtures of Cyhalofop-butyl, Bispyribenzoxim and Pyrazosulfuron-ethyl - I. Interaction of Herbicide Mixture (Cyhalofop-butyl, Bispyribenzoxim 및 Pyrazosulfuron-ethyl의 상호작용효과(相互作用效果) 및 상호작용(相互作用) 기작(機作)에 관(關)하여 - 제(第) 1 보(報) 제초제간(除草劑間)의 상호작용효과(相互作用效果))

  • Wu, Ming-Gen;Kim, Kil-Ung;Shin, Dong-Hyun
    • Korean Journal of Weed Science
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    • v.18 no.2
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    • pp.154-160
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    • 1998
  • This study was conducted to develop a foliar applied herbicide mixture covering wide spectrum weeds in dry direct seeded rice. Uniform precision central composite design(UPCCD) was employed to evaluate the effect of herbicide mixture among cyhalofop-butyl(cyhalofop), bispyribenzoxim and pyrazosulfuron-ethyl(pyrazosulfuron) having different weed control spectrum and to determine the best application rates of the three herbicide mixtures. The partial additive effect was observed in the mixture of cyhalofop and bispyribenzoxim with pyrazosulfron against Echinochloa crus-galli Beauv var crus-galli L., attributed to the negative interaction between cyhalofop and bispyribenzoxim system. Additive effect was observed in the mixture of bispyribenzoxim and pyrazosulfuron against Cyperus serotinus R. and Aneilema keisak H. but cyhalofop had no effect on these weeds. The most appropriate rate of the mixture of cyhalofop with bispyribenzoxim and pyrazosulfuron was 100 : 12 : 10g ai/ha exhibiting $ED_{90}$ against three weeds such as E. crus-galli, C. serotinus and A. keisak.

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Purification and Cellular Localization of Extracellular Nuclease of Serratia marcescens Expressed in Escherichia coli (대장균에 발현된 Serratia marcescens의 Nuclease의 정제와 세포내 분포)

  • Kim, Woe-Yeon;Lee, Hoon-Sil;Suh, Sook-Jae;Cho, Moo-Je;Lee, Sang-Yeol;Kim, Jae-Won
    • Korean Journal of Microbiology
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    • v.32 no.2
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    • pp.147-154
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    • 1994
  • Nuclease was secreted to the environmental media from the Escherichia coli JM107 tranformant harboring the extracellular nuclease gene of Serratia marcescens in the plasmid of pNUC4. Under the growth conditions, the amount of secreted enzyme was increased in parallel with bacterial growth conditions, the amount of secreted enzyme was increased in parallel with bacterial growth. The enzyme was purified using chromatofraphic procedures of Matrex green gel and heparin agarose affinity gel, resulted in 50-fold purification with 15% recovery of the enzyme. The apparent molecular weight of the enzyme was estimated to be 29Kda by sodium dodecylsulfate denaturing gel electrophoresis. Using the purified enzyme, polyclonal antibody was obtained from the rabbit. The specificity of the antibody was confirmed by immunoblotting and immunoprecipitaion. For the investigation of cellular distribution of the enzyme, cells were fractionated into three fractions; cytoplasm, periplasm and extracellular fluid. While more than 80% of the enzymatic activity was detected in the extracellular fluid and periplasm, a little was found in the cytoplasm, indicating that the enzyme was likely to be immediately exported to the membrane for excretion after biosynthesis. These results were confirmed again by immunocytochemistry technique using the antibody.

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Genetic polymorphisms of monoamine oxidase(MAO) B and serotonin transporter receptor(5-HTTR) influence variability in neurobehavioral symptoms by n-hexane exposur (n-Hexane 노출에 의한 신경행동학적 증상에 monoamine oxidase(B)와 serotonin transporter receptor 유전자다양성의 영향)

  • Kim, Ki-Woong
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.21 no.2
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    • pp.116-122
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    • 2011
  • Human occupational exposure to n-hexane has been associated with neurobehavioral symptoms such as depression, irritablity, acute irritation symptom, concentration disturbance and fatigue. Effects of monoamine oxidase (MAO) B and serotonin transporter receptor (5-HTTR) polymorphisms on the neurobehavioral symptoms were investigated in 70 male workers from TV and computer monitor manufacturing plants exposed to n-hexane. Neurobehavioral symptoms were assessed through a self-reported questionnaire and ambient level of n-hexane was measured by NIOSH method. Blood and urine were collected from each workers to determine the MAO(B), 5-HTTR and urinary 2,5-hexanedione(2,5-HD). The mean concentration of volatile n-hexane was $18.8{\pm}28.8ppm$ and that of urinary 2,5-HD was $1.07{\pm}1.47mg/g$ creatinine. Statistically significant associations with sexual disturbance were age and smoking. The frequencies of MAO(B) AA, AG and GG were 18.6%, 45.7% and 35.7%, respectively, and the frequencies of 5-HTTR ll, ls and ss genotype were 82.9%, 15.7% and 1.4%, respectively. MAO (B) gene polymorphisms had susceptibility to the neurobehavioral symptoms such as fatigue, concentration disturbance, irritability and acute irritation symptom and 5-HTTR gene polymorphism had susceptibility to the sleep disturbance and acute irritation symptom. On multiple logistic regression analysis for the neurobehavioral symptoms, memory disturbance was significantly associated with smoking(OR=6.752, 95% CI=37.46) and drinking(OR=4.033, 95% CI=1.252-12.98), emotional lability was MAO(B) genotype(OR=0.412, 95% CI=0.170-0.996), fatigue (OR=1.011, 95% CI=1.000-1.021) and acute irritation(OR=0.990, 95% CI=0.981-1.000) were working duration and sexual disturbance were significantly associated with age(OR=1.208, 95% CI=1.042-1.399), ambient n-hexane(OR=1.077, 95% CI=1.005-1.154) and 2,5-HD(OR=0.186, 95% CI=0.041-0.841). This finding implies that the MAO (B) and 5-HTTR polymorphisms may affect susceptibility for specific neurobehavioral symptoms associated with n-hexane exposure in workers.

The Determinants of Purchasing Private Health Insurance in Korean Cancer Patients (암 환자의 민간의료보험 가입 실태와 관련 요인)

  • Lim, Jin-Hwa;Kim, Sung-Gyeong;Lee, Eun-Mi;Bae, Sin-Young;Park, Jae-Hyun;Choi, Kui-Son;Hahm, Myung-Il;Park, Eun-Cheol
    • Journal of Preventive Medicine and Public Health
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    • v.40 no.2
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    • pp.150-154
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    • 2007
  • Objectives : The aim of this study is to identify factors determining the purchase of private health insurance under the mandatory National Health Insurance(NHI) system in Korea. Methods : The data were collected by the National Cancer Center in Korea. It includes cancer patients who were newly diagnosed with stomach (ICD code, C16), lung(C33-C34), liver (C22), colorectal cancer(C18-C20) or breast(C50) cancer. Data were gathered from the hospital Order Communication System (OCS), medical records, and face-to-face interviews, using a structured questionnaire. Clinical, socio-demographic and private health insurance related factors were also gathered. Results : Overall, 43.9% of patients had purchased one or more private health insurance schemes related to cancer, with an average monthly premium of \65,311 and an average benefit amount of \19million. Females, younger aged, high income earners, national health insurers and metropolitan citizens were more likely to purchase private health insurance than their counterparts. Conclusions : About half of Korean people have supple-mentary private health insurance and their benefits are sufficient to cover the out-of-pocket fees required for cancer treatment, but inequality remains in the purchase of private health insurance. Further studies are needed to investigate the impacts of private health insurance on NHI, and the relationship between cancer patients' burden and benefits.

Photoelastic Stress Analysis for a Rhombus Plate under Compressive Load Using Image Processing Technique (압축하중을 받는 마름모 판에 대한 영상처리기법을 이용한 광탄성 응력 해석)

  • Liu, Guan Yong;Kim, Myung Soo;Baek, Tae Hyun
    • Journal of the Korean Society for Nondestructive Testing
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    • v.34 no.2
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    • pp.148-154
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    • 2014
  • Photoelasticity is a useful technique for obtaining the differences and directions of principal stresses in a model. In conventional photoelasticity, the photoelastic parameters are measured manually point by point. Identifying and measuring photoelastic data is time-consuming and requires skill. The fringe phase shifting method was recently developed and has been found to be convenient for measuring and analyzing fringe data in photo-mechanics. This paper presents an experimental study on the stress distribution along a horizontal line that passes the central point of a rhombus plate made of Photoflex (i.e., type of urethane rubber). The isoclinic fringe and/or principal stress direction is constant on this horizontal line, so a four-bucket phase shifting method can be applied. The method requires four photoelastic fringes that are obtained from a circular polariscope by rotating the analyzer at $0^{\circ}C$, $45^{\circ}C$, $90^{\circ}C$ and $135^{\circ}C$. Experimental measurements using the method were quantitatively compared with the results from FEM analysis; the results from the two methods showed comparable agreement.

In-situ Self-calibration of Non-metric Camera and Digital Stereo Plotting for Public Survey (공공측량 적용을 위한 비측정용 카메라의 현장자체검정 및 수치 입체 도화)

  • Seo, Sang-Il;Lee, Byoungkil
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.35 no.3
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    • pp.145-154
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    • 2017
  • In recent years, demand for 1 / 1,000 digital map production has increased in various fields such as construction and urban planning. As a result, the use of low-cost non-metric cameras that replace expensive aerial photogrammetry equipment is required. In Korea, researches are being continuously carried out to produce a large scale digital map by photographing a small target area with a non-metric camera. However, due to the limitation of the accuracy of the non-metric camera, it is difficult to do digital mapping with stereoscopic photographs. In this study, we tried to verify the possibility of large-scale digital mapping to utilize non-metric camera for public survey. For this purpose, the accuracy of the digital mapping results of the non-metric camera and the results of the DMC camera were compared and analyzed. After performing in-situ self-calibration including 8 standard additional parameters, we plotted to a scale of 1/1,000 and confirmed that the RMSE is suitable for public survey accuracy of ${\pm}0.145m$ in horizontal and ${\pm}0.153$ m in vertical.

Sleep-Inductive Effect of GABA on the Fermentation of Mono Sodium Glutamate (MSG) (Mono sodium glutamate (MSG) 발효 GABA의 수면유도 효과)

  • Kim, Seung-Seop;Oh, Sung-Ho;Jeong, Myoung-Hoon;Cho, Seok-Cheol;Kook, Moo-Chang;Lee, Seok-Ho;Pyun, Yu-Ryang;Lee, Hyeon-Yong
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.142-146
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    • 2010
  • Relatively large amounts of GABA can be produced by the fermentation of rice bran. Therefore, this study was conducted to investigate the effects of GABA on the secretion of melatonin and serotonin for the development of a sleep inductive compound. The secretion levels of melatonin and serotonin from mice were found to be $3.425{\pm}0.182\;pg/mL$ and $5.37{\pm}0.963\;ng/mL$, respectively, in response to feeding 120 mg/mL of GABA while they were $2.607{\pm}0.41\;pg/mL$ in the control. The secretion of both melatonin and serotonin was increased up to the 13.51% and 34.99%, respectively, when compared to the negative control. However, the feeding of milk alone did not have a great effect on the melatonin and serotonin secretions. Conversely, feeding of milk with GABA enhanced the secretion of serotonin. The amounts of both melatonin and serotonin secreted increased with respect to the increase in GABA concentrations during feeding. Interestingly, the induction level of melatonin was relatively higher than that of serotonin in response to feeding 120 mg/mL of GABA. This is the first study to report that GABA has an ability to induce sleep related hormones in mice; therefore, it has the potential for use as a natural sleep aid.

Chemical Changes of Low Salt Gulbi (salted and dried yellow corvenia) during Hot-air Drying with Different Temperatures (저염 굴비 제조 시 열풍건조 온도에 따른 화학적 특성 변화)

  • Gwak, Hyun-Jung;Eun, Jong-Bang
    • Korean Journal of Food Science and Technology
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    • v.42 no.2
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    • pp.147-154
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    • 2010
  • Gulbi, made of fresh yellow corvenia (Psendosciaena manchurica) that has been salted and dried, is one of the most popular traditional marine foods in Korea. The objective of this study was to develop a method to safely manufacture Gulbi with low levels of oxidation and contamination, by a hot air drying method. Changes in total acidity, pH, salt concentration, thiobarbituric acid-reactive substance (TBARS) and volatile basic nitrogen (VBN) were measured during drying at 30, 35 and $40^{\circ}C$ for 15 days in a hot air-dryer using a semi-dried method. Acidity increased with increasing drying time at all drying temperatures. The pH decreased gradually with increasing drying time. Salt concentration was increased as drying time increased at all drying temperatures due to moisture loss. The VBN increased as drying time increased for all drying temperatures. Data indicate that the drying at $35^{\circ}C$ appears to have a significant sensory and physicochemical advantage in Gulbi products.