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Effect of Lipoxygenase on the Oxidation of Rainbow Trout Lipid in Model system (모델시스템에 있어서 무지개 송어 지방질의 산화에 대한 Lipoxygenase의 영향)

  • Kim, Hae-Gyoung;Um, Su-Hyon;Cheigh, Hong-Sik
    • Journal of Life Science
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    • v.5 no.2
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    • pp.14-14
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    • 1995
  • The effect of lipoxygenase (LOX) on the oxidation and co-oxidation of lipid fraction was studied in the model system of rainbow trout. For the reaction in model system 1 g of lipid fraction and 50mL of enzyme extract(LOX, 140 unit in 50mL phosphate buffer solution at pH 7,4)), which were obtained from rainbow trout, were homoginized in the presence of Tween 20 and kept at 23$\circ$C for 3 days. The activity of LOX was decreased to 43% of initial level during the reaction in the model system. The initial composition of rainbow trout lipid was showed to be consisted of trigliceride(TG;82%) and free fatty acid(FFA;0.1%), while this converted to 59% of TG and 20% of FIFA, respectively after reaction in model system. Change of fatty acid composition was also observed and the content of linoleic acid, one of the major fatte acids, was decreased to 13% from 54% in the content of total fatty acids after reaction. The carotenoids in rainbow trout were composed of 0.4% $\alpha$-carotene, 1.6% $\beta$ -carotene, 80% canthaxanthin, 7% lutein and 11% zeaxanthin, thus the canthaxanthin was the major component. This canthaxanthin was the most degraded carotenoid by lipoxygenase catalyzed co-oxidation during the reaction. On the other hand the tocopherol isomers found in the rainbow trout were $\alpha$ and $\beta$ -tocopherol, and $\alpha$-tocopherol had a higher degradation rate by the lipoxygenase catalyzed co-oxidation than of $\beta$-tocopherol in the reaction of model system.

Translating Evidence into Practice in Low Resource Settings: Cervical Cancer Screening Tests are Only Part of the Solution in Rural India

  • Isaac, Rita;Finkel, Madelon;Olver, Ian;Annie, I.K.;Prashanth, H.R.;Subhashini, J.;Viswanathan, P.N.;Trevena, Lyndal J.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.4169-4172
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    • 2012
  • Background: The majority of women in rural India have poor or no access to cervical cancer screening services, although one.quarter of all cervical cancers in the world occur there. Several large trials have proven the efficacy of low-tech cervical cancer screening methods in the Indian context but none have documented the necessary components and processes of implementing this evidence in a low-resource setting. Methods: This paper discusses a feasible model of implementation of cervical cancer screening programme in low-resource settings developed through a pilot research project carried out in rural Tamilnadu, India. The programme used visual inspection of cervix after acetic acid application (VIA) as a screening tool, nurses in the primary care centres as the primary screeners and peer educators within Self-Help Women groups to raise community awareness. Results: The uptake of screening was initially low despite the access to a screening programme. However, the programme witnessed an incremental increase in the number of women accessing screening with increasing community awareness. Conclusions: The investigators recommend 4 key components to programme implementation in low-resource setting: 1) Evidence-based, cost-effective test and treatment available within the reach of the community; 2) Appropriate referral pathways; 3) Skilled health workers and necessary equipment; and 4) Optimisation of health literacy, beliefs, attitudes of the community.

Electrokinetic Property and Flotation Characteristics of Scheelite (灰重石의 水溶液中에 있어서의 界面現象과 浮選特性에 關한 硏究)

  • Hyung Sup Choi;Kook Nam Han
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.17-24
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    • 1963
  • The fundamental investigations of surface properties of scheelite were made by electrophoretic mobility adsorption and contact angle measurements, and results have been correlated with its floatability obtained by Hallimond tube flotation test. The role of the interfacial electrical condition on the adsorption of collectors on mineral surfaces is discussed with the flotation of scheelite. From electrokinetic measurements made on scheelite, $Ca^{++}$ and $WO_4^{--}$ are identified to act as potential-determining ions, thus controlling the surface properties on this mineral. Therefore, at the fixed pH, the scheelite surface become to be less negatively charged with increasing $Ca^{++}$ concentration and more negatively charged with increasing $WO_4^{--}$ concentration in the pulp. Adsorption of collectors then depends strongly on the concentration of $Ca^{++}$ or $WO_4^{--}$ in the solution; anionic collectors are adsorbed on less negatively charged surfaces and cationic collectors on more negatively charged surfaces, which in turn defines the effective flotation range with respective collectors for this mineral.

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Novel Solid Phase Extraction Procedure for Some Trace Elements in Various Samples Prior to Their Determinations by FAAS

  • Sacmaci, Srife;Kartal, Senol;Sacmaci, Mustafa;Soykan, Cengiz
    • Bulletin of the Korean Chemical Society
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    • v.32 no.2
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    • pp.444-450
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    • 2011
  • A novel method that utilizes poly(5-methyl-2-thiozyl methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinylbenzene) [MTMAAm/AMPS/DVB] as a solid-phase extractant was developed for simultaneous preconcentration of trace Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), and Zn(II) prior to the measurement by flame atomic absorpiton spectrometry (FAAS). Experimental conditions for effective adsorption of the metal ions were optimized using column procedures. The optimum pH value for the simultaneously separation of the metal ions on the new adsorbent was 2.5. Effects of concentration and volume of elution solution, sample flow rate, sample volume and interfering ions on the recovery of the analytes were investigated. A high preconcentration factor, 100, and low relative standard deviation values, $\leq$1.5% (n = 10), were obtained. The detection limits (${\mu}gL^{-1}$) based on the 3s criterion were 0.18 for Cd(II), 0.11 for Co(II), 0.07 for Cr(III), 0.12 for Cu(II), 0.18 for Fe(III), 0.67 for Mn(II), 0.13 for Ni(II), 0.06 for Pb(II), and 0.09 for Zn(II). The validation of the procedure was performed by the analysis of two certified reference materials. The presented method was applied to the determination of the analytes in various environmental samples with satisfactory results.

Antioxidant Activity of Saururus chinensis Pretreated by Mechanochemical Technology - Nitrite Scavenging and Electron Donating Ability -

  • Song, Won-Seob;Park, Keum-Joo;Choung, Eui-Su
    • Korean Journal of Plant Resources
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    • v.24 no.3
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    • pp.314-318
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    • 2011
  • Saururus chinensis is used as a raw material of an anti-rheumatic, poultice, sedative and stomachic. The tea of dried Saururus chinensis leaves has a function of relaxing pains in back and breast and of treating stomach ailments. The plant has the functions of anti-inflammatory, depurative, diuretic, febrifuge and refrigerant. The extraction of functional material is carried out by methanol and ethanol solvents. Mechanochemical grinding is applied as a pretreatment process before extraction to enhance the extraction efficiency by increasing the surface area of the materials while changing the chemical properties of the materials. Extraction of functional materials from the Saururus chinensis after grinding as a pretreatment using the mechanochemical technology was accomplished in this study to investigate the effect of grinding on the antioxidant activities of the extract. Saururus chinensis was ground by the planetary ball mill and the morphology was analyzed by SEM. Mechanochemical pretreatment increased the yields of functional materials from 5.9 g to 6.4, 7.0, and 8.1 g after grinding of 30 minutes, 1 hour and 2 hours, respectively. Nitrite scavenging ability increased from 53.0-71.0% to 61.0-79.0% for the methanol extraction in the solution of pH 1.2. Also, Electron donating abilities were increased from 7.90-33.51% to 11.97-38.51% for the methanol extraction. The extract concentration for the half inhibition of DPPH radicals was reduced from $278{\mu}g/mL$ in the original sample to $263{\mu}g/mL$ in the sample after grinding for the methanol extraction.

Management Strategies for Heavy Metals to Secure the Crop Safety in Korea

  • Yang, J.E.;Kim, W.I.;Ok, Y.S.;Lee, J.S.
    • 한국환경농학회:학술대회논문집
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    • 2009.07a
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    • pp.93-115
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    • 2009
  • There are growing public concerns over crop and food safeties due to the elevated levels of heavy metals grown in contaminated soil. Heavy metals are classified as the chemical harmful risks for crop and food safety. With implementation of GAP, crop safety is controlled by many regulatory options for soil, irrigation water and fertilizers. Any attempt to retard the metal uptake by crops may be the best protocol to secure crop and food safety. This article reviews the management strategies for heavy metals in view of crop safety in Korea and demonstrates results from the field experiments to retard metal translocation from soil to crops by using chemical amendments and soil layer management methods. Major source of soil pollution by heavy metals has been related with mining activities. Risk assessment revealed that rice consumption and groundwater ingestion in the abandoned mining areas were the major exposure pathways for metals to human and the heavy metal showed the toxic effects on human health. Chemical amendments such as lime and slag retarded Cd uptake by rice (Oryza sativa L.) by increasing soil pH, lowering the phytoavailable Cd concentration in soil solution, immobilizing Cd in soil and converting the available Cd fractions into non-available fractions. The soil layer management methods decreased the Cd uptake by 76% and Pb by 60%. Either reversing the surface layer with subsurface layer or immobilization of metals with layer mixing with lime was considered to be the practical option for the in-situ remediation of the contaminated paddy soils. Combination of chemical soil amendments and layer management methods was efficient to retard the metal bioavailability and thus to secure crop safety for heavy metals. This protocol seems to be cheap, relatively easy to practice and practical in the agricultural fields. However, a long term monitoring work should be followed to verify the efficiency of this protocol.

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Methodology of Chromosome Preparation and Banding Analysis in Gallus domesticus (닭 염색체의 분리 분석 방법에 관한 연구)

  • 손시환;오봉국
    • Korean Journal of Poultry Science
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    • v.14 no.2
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    • pp.89-96
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    • 1987
  • The purpose of this paper to present morphological normal chick chromosomes and develope avian cytogenetic techniques including chromosome preparation and banding technique. The early chick embryos provide a consistent source of material with hish mitotic cells. Although chick embryo tissue gives excellent preparations, the 4-5 days embryo is somewhat incovenient materials, Most imp of ant for avian Chromosome analysis are the technical protocols to achieve adequate preservation, spreading, and staining of the full chromosome complement. To precise chromosome analysis, pro-metaphase states are required. Best results of banding will be obtained from air dried slides prepared from early chick embryos that have been aged at least 1 week. Good G-banding differentiation is achieved by adequate trypsin digestion fellowed by staining in Goe,sa dye. The results of C-banding is influenced by many factors including the conditions of Ba(OH)$_2$, HCl treatment, and state of rinsing. In addition to precisely interprets banding patterns, the densitometric analysis is recommended.

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TiO2 Reuse and Recovery from the Photocatalytic Oxidation of Cu(II)-EDTA using TiO2/UV-A System (TiO2/UV-A 시스템을 이용한 Cu(II)-EDTA의 광촉매 산화반응에서 TiO2 재사용 및 회수)

  • Lee, Seung-Mok
    • Journal of Korean Society on Water Environment
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    • v.21 no.1
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    • pp.84-91
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    • 2005
  • $TiO_2-catalyst$ suspensions work efficiently in Photocatalytic oxidation (PCO) for wastewater treatment. Nevertheless, once photocatalysis is completed, separation of the catalyst from solution becomes the main problem. The PCO of Cu(II)-EDTA was studied to determine the reusability of the titanium dioxide catalyst. Aqueous solutions of $10^{-4}M$ Cu(II)-EDTA were treated using illuminated $TiO_2$ particles at pH 6 in a circulating reactor. $TiO_2$ was reused in PCO system for treatment of Cu(II)-EDTA comparing two procedures: reuse of water and $TiO_2$ and reuse of the entire suspension after PCO of Cu(II)-EDTA. The results are as follows; (i) Photocatalytic efficiency worsens with successive runs when catalyst and water are reused without separation and filtration, whereas, when $TiO_2$ is separated from water, the reused $TiO_2$ is not deactivated. (ii) The $TiO_2$ mean recovery (%) with reused $TiO_2$ was 86.4%(1.73g/L). Although the mean initial degradation rate of Cu(II)-EDTA and Cu(II) was lower than that using fresh $TiO_2$, there was no significant change in the rate during the course of the three-trial experiment. It is suggested that Cu(II)-EDTA could be effectively treated using an recycling procedure of PCO and catalyst recovery. (iii) However, without $TiO_2$ separation, the loss of efficiency of the PCO in the use of water and $TiO_2$ due to Cu(II), DOC remained from previous degradation and Cu(II)-EDTA added to the same suspension was observed after 2 trials, and resulted in the inhibition of the Cu(II)-EDTA, Cu(II) and DOC destruction.

Removal Characteristics of Phosphorus at Synthetic Variation of Zirconium Mesoporous Structure (지르코늄 메조기공 구조체의 합성조건 변화에 따른 인 제거 특성)

  • Lee, Sang-hyup;Lee, Byoung-cheun;Lee, Kwan-yong;Choi, Yong-su;Park, Ki-young
    • Journal of Korean Society on Water Environment
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    • v.21 no.6
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    • pp.637-642
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    • 2005
  • The focus of this study was to examine the phosphorus removal characteristic by zirconium mesoporous structured material synthesized on various conditions. The zirconium sulfate-surfactant mesoporous structured material(ZS) was synthesized by hydro-thermal synthesis. The material has regular hexagonal array of surfactant micelles and sulfate ion ($HSO_4{^-}$). We confirmed that sulfate ion in zirconium mesoporous structured material can be ion-exchanged with phosphate ion ($H_2PO_4{^-}$) in phosphoric acid solution. On the X-ray diffraction (XRD) pattern of ZS, three peaks which shows the important characteristics of hexagonal crystal lattice were observed at (100), (110) and (200). The transmission electron micrograph (TEM) show high crystallization with pore size about $47{\AA}$. The maximum adsorption capacity of ZS was as great as 3.2 mmol-P/g-ZS. From the adsorption isotherm, correlation coefficients were higher for the Langmuir isotherm than the Freundlich isotherm. With the respect of chain length of surfactant, the adsorption capacity for phosphate synthesized with C12 was higher than C16 and C18. The highest amount of adsorbed phosphate on ZS was observed at the surfactant-to-zirconium molar ratio of 0.5 to 1.

A Study on the Dyeing of CDP(cation dyeable polyester)/Silk Knitted Fabrics With Disperse Type Cation Dyes/Acid Dyes (분산형캐티온염료/산성염료에 의한 CDP(cation dyeable polyester)/견 교편물의 염색에 관한 연구)

  • Sung, Woo-Kyung
    • Fashion & Textile Research Journal
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    • v.13 no.5
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    • pp.797-805
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    • 2011
  • This study was carried out to investigate dyeing characteristics of CDP(cation dyeable polyester)/silk knitted fabrics with disperse type cation dyes/acid dyes by one bath dyeing method in comparison with two bath dyeing method in the interests for rationalization of the dyeing process. The apparent color depth(K/S) of the disperse type cation dyes with CDP and that of acid dyes with silk decreased slowly with increasing pH values of dyebath with the exception of sharp decrease at alkali region for CDP. The contamination behavior of CDP by the acid dyes and that of silk by the disperse type cation dyes decreased with progressing of dyeing. The migration ratio(%) of the disperse type cation dyes with CDP is low compared with that of acid dyes with silk. The sediment in mixed dying solution of disperse type cation dyes and acid dyes remarkably less compared with that of regular type cation dyes and acid dyes at $100^{\circ}C$ regardless applying of preventer agent of precipitation. When CDP/silk knitted fabrics was dyed with by with mixtures of disperse type cation dyes/acid dyes one bath or two bath dyeing method, the characteristic of reflectance spectra of CDP components were greatly influenced by disperse type cation dyes and that of silk components by acid dyes. It was confirmed that K/S values of each components of CDP/silk knitted fabrics dyed by one bath dyeing method decreased slightly compared with two bath dyeing method.