• Title/Summary/Keyword: As₂O₃

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Rhizosphere Enhances Removal of Organic Matter and Nitrogen from River Water in Floodplain Filtration (홍수터 여과를 이용한 하천수의 질소와 유기물 제거에 미치는 근권의 효과)

  • Jeong, Byeong-Ryong;Chung, Jong-Bae;Kim, Seung-Hyun;Lee, Young-Deuk;Cho, Hyun-Jong;Baek, Nam-Joo
    • Korean Journal of Soil Science and Fertilizer
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    • v.36 no.1
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    • pp.8-15
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    • 2003
  • If contaminated river water is sprayed over a floodplain, the microbial processes can simultaneously remove organic matter and nitrogen during the infiltration through the sediment profile. The effect of rhizosphere on the removal of organic matter and nitrogen from contaminated river water was investigated using floodplain lysimeters. River water was sprayed at a rate of $68.0L\;m^{-2}\;d^{-1}$ on the top of the lysimeters with or without weed vegetation on the surface, Concentrations of $NO_3$, $NH_4$ and dissolved oxygen (DO), and chemical oxygen demand (COD) and Eh in water were measured as functions of depth for 4 weeks after the system reached a steady state water flow and biological reactions. A significant reductive-condition for denitrification developed in the 30-cm surface profile of lysimeters with weeds. At a depth of 30 cm, COD and $NO_3$-N concentration decreased to 5.2 and $0.9mg\;L^{-1}$ from the respective influent concentrations of 18.2 and $9.8mg\;L^{-1}$. The removal of $NO_3$ in lysimeters with weeds was significantly higher than in those without weeds. Vegetation on the top was assumed to remove $NO_3$ directly by absorption and to create more favorable conditions for denitrification by supply of organic matter and rapid $O_2$ consumption, In the lysimeters without weeds, further removal of $NO_3$ was limited by the lack of an electron donor, i.e. organic matter. These results suggest that the filtration through native floodplains, which include rhizospheres of vegetation on the surface, can be effective for the treatment of contaminated river water.

Vertical Distribution of the Heavy Metal in Paddy Soils of Below Part at Guundong Mine in Milyang, Korea (구운동 폐광산 하류 논토양의 토심별 중금속함량)

  • Yun, Eul-Soo;Park, Sung-Hak;Ko, Jee-Yeon;Jung, Ki-Yeol;Park, Ki-Do;Hwang, Jae-Bok;Park, Chang-Yeong
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.5
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    • pp.590-595
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    • 2010
  • This study was conducted to investigate form of pollution brought by residual of mine tailing in agricultural land, and get basic information need for environment restoration. Guundong mine was completely restored region by implementation the soil pollution prevention plan. The districts is soils in Guundong mine vicinity the Mahul-ri, Muan-myeon, Miryang city, Gyeongsangnam-do. The nature of soil studied is the Shinra series andesite and mineral deposits which contain brimstone and heavy metals such as gold, silver, copper, lead, and zinc. The residual mine tailing and around agricultural land of heavy metals analyzed with 0.1N HCI solubility. The chemical properties of surface soil in upper part around mining area were pH 4.3-4.4, organic matter 19-21 g $kg^{-1}$, available $P_2O_5$ 85 mg $kg^{-1}$, exchangeable Ca 0.21-0.25 $cmol_c\;kg^{-1}$, exchangeable Mg 0.04 $cmol_c\;kg^{-1}$. The pH, exchangeable Ca, and Mg were increased with soil depth. The contents of 0.1N HCl extractable Cu, Cd, Pb, Cr, and Ni in soil (siteI) which influenced by outflow water from mine tailing were 97, 0.6, 197, 0.28 및 0.12 mg $kg^{-1}$, respectively. The vertical distribution of heavy metals in soil varied considerably among the metals kind. In case of siteI, The content of Cu, Pb, and Cr in soil was highest at surface soil. However, the content of Cd, Zn, Ni, and Mn was high at middle part of soil profile.

On-line Image Guided Radiation Therapy using Cone-Beam CT (CBCT) (콘빔CT (CBCT)를 이용한 온라인 영상유도방사선치료 (On-line Image Guided Radiation Therapy))

  • Bak, Jin-O;Jeong, Kyoung-Keun;Keum, Ki-Chang;Park, Suk-Won
    • Radiation Oncology Journal
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    • v.24 no.4
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    • pp.294-299
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    • 2006
  • $\underline{Purpose}$: Using cone beam CT, we can compare the position of the patients at the simulation and the treatment. In on-line image guided radiation therapy, one can utilize this compared data and correct the patient position before treatments. Using cone beam CT, we investigated the errors induced by setting up the patients when use only the markings on the patients' skin. $\underline{Materials\;and\;Methods}$: We obtained the data of three patients that received radiation therapy at the Department of Radiation Oncology in Chung-Ang University during August 2006 and October 2006. Just as normal radiation therapy, patients were aligned on the treatment couch after the simulation and treatment planning. Patients were aligned with lasers according to the marking on the skin that were marked at the simulation time and then cone beam CTs were obtained. Cone beam CTs were fused and compared with simulation CTs and the displacement vectors were calculated. Treatment couches were adjusted according to the displacement vector before treatments. After the treatment, positions were verified with kV X-ray (OBI system). $\underline{Results}$: In the case of head and neck patients, the average sizes of the setup error vectors, given by the cone beam CT, were 0.19 cm for the patient A and 0.18 cm for the patient B. The standard deviations were 0.15 cm and 0.21 cm, each. On the other hand, in the case of the pelvis patient, the average and the standard deviation were 0.37 cm and 0.1 cm. $\underline{Conclusion}$: Through the on-line IGRT using cone beam CT, we could correct the setup errors that could occur in the conventional radiotherapy. The importance of the on-line IGRT should be emphasized in the case of 3D conformal therapy and intensity-modulated radiotherapy, which have complex target shapes and steep dose gradients.

Transarterial embolization of renal artery in dogs with experimental hydronephrosis (개의 실험적 수신증에 실시한 신동맥 색전술)

  • Chang, Dongwoo
    • Korean Journal of Veterinary Research
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    • v.41 no.3
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    • pp.437-445
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    • 2001
  • This study was performed to validate the procedure of transarterial embolization of the renal artery (TAE-RA) using iohexol-ethanol solution in dogs with unilateral experimental hydronephrosis and to evaluate the embolized kidney using B-mode ultrasonography and selective angiography. Experimental hydronephrosis was induced by ligation of unilateral ureter in 12 dogs. Ultrasonographic findings revealed that size of the kidney was significantly increased at 9 days and 17 days and the length of renal cortex was significantly decreased at 17 days after ligation of the unilateral ureter and it was in accordance with dilation of ipsilateral renal pelvis. No significant change of BUN, creatinine, ALT, calcium, and phosphorus was found immediately after unilateral experimental hydronephrosis. Therefore, it was concluded that unilateral hydronephrosis was established in 12 dogs at 17 days after ligation of ureter. Renal artery embolization was performed using selective catheterization in the hydronephrotic kidney of seven dogs and EKG, $SpO_2$, body temperature, pulse, and respiratory rate were within normal ranges during procedures. Iohexol-ethanol solution was used as embolic material. Average ethanol dose for renal artery embolization was $1.94{\pm}1.24ml/kg$. There were no dogs expired after TAE-RA and no side effects associated with regurgitation of iohexol-ethanol solution. Revascularization of renal artery was not found in angiography in dogs treated by TAE-RA at immediately after TAE-RA and 14 days after TAE-RA. Ultrasonographically, the mean longitudinal length of the embolized kidney decreased significantly at 2 and 3 months after TAE-RA compared to that of contralateral normal kidney. In summary, marked shrinkage of the embolized kidney was observed in dogs with unilateral experimental hydronephrosis treated by TAE-RA with iohexol-ethanol and no adverse effects were observed throughout the observation period. It is concluded that TAE-RA with iohexol-ethanol solution is a viable alternative to nephrectomy in dogs with unilateral hydronephrosis.

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Interspecific Competition of Paddy Rice Isogenic Lines in Plant Type with Some Perennial Weeds (수도초형(水稻草型)의 Isogenic Line과 다년생(多年生) 잡초(雜草)의 경합특성(競合特性) 연구(硏究))

  • Kim, I.K.;Guh, J.O.;Kwon, S.L.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.39-49
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    • 1983
  • By use of three paddy rice lines as the near-isogenic in plant type (Broom, Open, and Spread type in tillering angle), the interspecific competition patterns of rice plants with three important weed species (Cyperus serotinus, Eleocharis kuroguwai, and Potamogeton distinctus) under the three densities of weed standing (0.25 and 50 percent of the rice plants), were observed. Under the experimented conditions, paddy yields were varied more significantly with weed competition descriptions than with plant types of paddy rice. And spread typed rice was more competitive to the detected weed species, however, the broom and spread typed rice were to Potamogeton SP, among others. The result of the clustering analysis of crop-weed competition patterns, estimated by 1-Q mode correlation coefficients, indicated that the first-order component affecting the competition patterns of crop-weed was rather the plant types of rice than either weed species or weed standing densities.

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Differential Weed Competition of Two Rice Cultivars under Various Cropping Patterns (수도(水稻) 이품종(異品種)의 재배양식(栽培樣式)에 따른 잡초(雜草) 경합구조(競合構造) 해석(解析))

  • Guh, J.O.;Kwon, S.L.;Heu, S.M.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.57-68
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    • 1983
  • To estimate the possible amount of weed-crop competitions under the various cropping patterns of two rice cultivars of different type, comparisons between weedy check and weed-free plots in plant height, tillering number, and plant weight were investigated. Fluctuations in Importance Value, competition value, and net productivities were used to discuss the crop-weed competition, respectively. As a result, differences in dominant weed species, competitive crop variety, most effective cropping pattern, and crop yielding characteristics under the different weed competitions were investigated, respectively.

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Re-Cloning by Somatic Cell Nuclear Transfer from a Cloned Korean Native Goat (복제 산양(진순이)의 체세포 핵이식에 의한 Re-Cloning에 관한 연구)

  • Jung, S.Y.;Park, H.S.
    • Journal of Embryo Transfer
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    • v.22 no.2
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    • pp.89-95
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    • 2007
  • The present study was conducted to examine some factors affecting in vitro development and fecundity of embryos recloned with somatic cell nuclear transfer (SCNT). Fibroblast cells retrieved from the ear of a 3-week-old, cloned Korean goat (Jinsoonny) were used as karyoplast donors and serum-starvation was conducted in tissue culture medium (TCM)-199 supplemented with 0.5% FBS. Recipient oocytes were surgically collected by flushing the oviducts 35 h after hCG injection following FSH priming. The zonae pellucidae of the oocytes were partially perforated with a laser drill and a donor cell was transferred into an enucleated oocyte. The couplets were electrically fused and activated by ionomycin (5 min) and 6-DMAP (4 h). The reconstructed embryos were cultured in mSOF medium containing 0.8% BSA at $39^{\circ}C$ in an atmosphere of 5% $CO_2$, 5% $%O_2$, 90% $N_2$ for 12 to 15 h. Re-cloned embryos (2- to 4-cell stages) were surgically transferred into the oviducts of the recipients and pregnancy was subsequently diagnosed by progesterone assay and ultrasound on Days 21 and 63 of pregnancy. The fusion rate following 1st fusion pulse was higher (p<0.05) in 2nd cloning (65.9%) compared to 1st cloning (51.0%), but it was not different in the other groups. The rate of cleavage after fusion was significantly higher (p<0.05) in 1st (77.7%) than in 2nd cloning (56.0%). A total of 175 re-cloned embryos were transferred into 28 recipients. On day 21 and 60 after transfer, 11 (39.3%) and 4 recipients (17.4%) were pregnancy, respectively. In comparison of pregnancy rate by estrous synchronization, a total of 66 and 109 re-cloned embryos were transferred into 11 recipients in natural estrus and 17 recipients in induced estrus, respectively. Five (45.4%) and 2 recipients (18.2%) in natural estrus were pregnant on days 21 and 63 while 6 (35.3%) and 2 (11.8%) recipients in induced estrus were pregnant, respectively. These results show that recloning of goat can be achieved by SCNT and estrous synchronization between donor and recipient animals may be one of the major factors affecting success rate.

Chemical Composition of Perilla frutescens Britton var. Crispa Decaisne Cultivated in Different Areas of Korea -Part 1. Characteristics of Lipid and Fatty Acid Composition- (자소(紫蘇)의 산지별(産地別) 화학조성(化學組成) -제일보(弟一報) 지질(脂質)의 특성(特性) 및 지방산조성(脂肪酸組成)-)

  • Park, H.S.;Kim, J.G.;Cho, M.J.
    • Applied Biological Chemistry
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    • v.24 no.4
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    • pp.224-229
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    • 1981
  • Perilla (Perilla frutescens Britton var. Crispa Decasne) cultivated in three geographical areas of Korea, Gwangju, Taegu and Jeju, was analyzed for carbohydrate, lipid, protein, inorganic components and fatty acid composition. Carbohydrate, lipid and protein content of perilla seed ranged from 40 (Taegu) to 44% (Jelu), from 28 (Jeju) to 34% (Taegu) and from 15 (Gwangju) to 16% (Jeju), respectively. The overage contents of potassium, silicate, calcium, phosphate, iron, zinc, magnesium and mangane in the perilla seed varied between $426{\sim}446$, $197{\sim}229$. $124{\sim}136$, $46{\sim}56$, $30{\sim}49$, $42{\sim}45$, $40{\sim}45$, and $30{\sim}36mg%$, respectively and those variations different cultivation areas were not significant except iron. Saponification number, iodine value and acid value of the perilla oil were between $194{\sim}198$, $196{\sim}200$ and $4{\sim}5$, respectively. Those variations among the cultivation areas were not significant. The composition of the perilla oil was observed to be composed of $92{\sim}95%$ of triglyceride, $1.2{\sim}1.3%$ of phospholipid, $1.7{\sim}1.9%$ of unsaponifiables, $0.7{\sim}0.9%$ of free fatty acid, and $1.1{\sim}1.4$ linolenic, linoleic and oleic acid as $55{\sim}56$, $16{\sim}18$ and $16{\sim}20%$ of total fatty acids, but in phospholipid, the content of saturated fatty acids, $12{\sim}24$ of total fatty acid, was higher than that in triglyceride, $8{\sim}19%$ of total fatty acids. The content of saturated fatty acids in sterylester $(14{\sim}19%)$ was higher than that in sterylglycoside ($6{\sim}7%$ of total fatty acids). The variation in fatty acid composition was not significant in the composition of total fatty acid but a significant difference was observed in the composition of phospholipid, in which the content of palmitate ranged from 11.8%(Taegu) to 24%(Gwangju) of total fatty acids. No significant variation was found in the fatty acid composition among the cultivation areas, while a significant difference was observed in phospholipid.

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Long Term Results of Valve Replacement with the St. Jude Medical Heart Valves: Thirteen Year Experience (St. Jude 기계판막을 이용한 판막 치환술의 장기 성적)

  • Kim, Chang-Gon;Gu, Ja-Hong;Jo, Jung-Gu;Kim, Gong-Su
    • Journal of Chest Surgery
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    • v.30 no.9
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    • pp.891-898
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    • 1997
  • Between May 1984 and January 1996, 130 patients were replaced cardiac valve using 150 St. Jude Medical prosthetic valves(42 aortic, 68 mitral, 20 aortic and mitral valve replycements). Follow-up was 97.6% complete. The early mortality rate was 5.4%, and late mortality rate was 4.9%. The valve-related late mortality rate was 3.3%. Of late complications, there were 6 anticoagulant related hemorrhages, 4 thromboembolisms and 1 paravalvular leakage. Linearized rates of late complication and valve-related late mortality were as follows: total late complications, .1.68o per patient-year: anticoagulant related hemorrhages, 0.92% per patient-year: thromboembolism, 0.61% per patient-year: paravalvular leakage, 0.15% per patient-year: reoperation, 0.15% per patient-year: and valve-related late mortalities, 0.61% per patient-year. Actuar al event free rate at 10 years was 87.4 $\pm$ 3.2%. The overall actuarial survival rate was 90.4$\pm$2.7% at 5 years, 87.5$\pm$3.3% at 10 years. Ninety eight percent of the survivors were in the New York Heart Association functional class I or II at the end of follow-up. There was significant improvement of cardiothoracic ratio. In conclusion, this study suggests the excellent durability of the St. Jude Medical Heart valve and remarkable functional benefit for the majority of the patients. However, prosthesisrelated complications are still common. Outcome is strongly related to the patient's preoperative cardiac condition and to the adequacy of anticoagulation control.

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Effects of Egg Storage, Storage Temperature, and Insemination of Hens on Egg Quality (계란의 저장기간, 저장온도 및 암닭의 수정이 계란의 품질에 미치는 영향)

  • Suk Y. O.;Kwon J. T.
    • Korean Journal of Poultry Science
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    • v.31 no.4
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    • pp.203-212
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    • 2004
  • A total of 1,200 eggs obtained from 312-day-old Hy-line Brown laying breeder hens and 319-day-old Hy-line Brown commercial laying hens (600 eggs obtained from each one) at same day were used to investigate the effects of egg storage, storage temperature, and insemination of hens on the change of albumen height, Haugh unit(HU), albumen pH, shell strength, and yolk color. Eggs were stored up to 14 days after lay at $3^{\circ}C$ or $10^{\circ}C$ and sampled one day after stored and then 24 hours interval. Longer periods of storage resulted in lower albumen height and HU at both storage temperatures, but in higher albumen pH. The eggs stored at $3^{\circ}C$ were significantly (P<0.05) higher in HU and lower in albumen pH than the ones stored at $10^{\circ}C$. The eggs obtained from the non-inseminated-hens were significantly (P<0.05) higher in albumen height, HU, and albumen pH than the eggs obtained from the inseminated-hens. Whereas, the eggs obtained from the non-inseminated-hens in the mean albumen pH of eggs stored at $3^{\circ}C$ were significantly (P<0.05) higher than the ones obtained from the inseminated-hens, but the mean albumen pH of eggs stored at 10^{\circ}C did not differ each other. The mean shell strength of the eggs obtained from the inseminated-hens was significantly (P<0.05) stronger than that of the eggs obtained from the non-inseminated-hens at both storage temperatures. Albumen height and albumen pH were negatively correlated $(P<0.01\~0.001)$ in both inseminated and non-inseminated-hen's egg groups. The degree of yolk colors was not significantly changed overall of the experimental periods in both storage temperatures. The study suggests that the change of egg freshness such as albumen height and HU is relatively more associated with storage period and storage temperature than insemination or non-insemination of hens.