• Title/Summary/Keyword: PEC

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Effect of Glycyrrhiza glabra Extracts on Immune Response (감초 추출물이 면역응답에 미치는 영향)

  • Sim, Ho-Ki;Park, Mu-Hee;Choi, Chung;Bae, Man-Jong
    • The Korean Journal of Food And Nutrition
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    • v.10 no.4
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    • pp.533-538
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    • 1997
  • This study was conduced to investigate on immune response of the hot water extract(PHE), 50% methanol extract(PME) and acetone extract(PAE) from Glycyrrhiza glabra. The experiment was carried out by phagocytosis, plaque forming cell(PFC), hemalysin titration(HY) and rosette forming cell(RFC) assay by using BALB/c mice. The results obtained from this study are as follow ; The effects of Glycyrrhiza glabra extracts on phagocytosis was tended to be slight increase in GME and GAE groups compared to the control group, but not significant. In the experiment of PFC and HY, the results of experiment groups which was given each samples were significantly higher than the control group. The result of rosette forming cell in GME and GAE groups were significantly higher than control group.

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The Effect of Thermal Storage/Release and Moisture Transport Properties of Polyethylene Glycol-Treated Acrylic Athletic Socks on the Wear Performance (Polyethylene Glycol 처리한 아크릴 운동용 양말의 축열 . 방열성과 수분전달 특성이 착용 성능에 미치는 영향)

  • 조길수;이은주
    • Journal of the Korean Society of Clothing and Textiles
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    • v.19 no.1
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    • pp.36-50
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    • 1995
  • The purpose of this study was 1) to estimate the improvement of thermal storage/release and moisture transport properties of PEG-treated acrylic athletic socks and suggest the optimum add-on for PEG treatment, 2) to investigate wear performance of untreated cocks and two kinds of socks treated with PEG of minimum and optimum add-on respectively, and 3) to consider the effect of thermal storage/release and moisture transport properties of PEG- treated socks on the wear performance and the subjective comfort zone. Thermal activities of specimens treated by PDC were evaluated on a DSC by measuring the heat of fusion on heating and the heat of crystallization on cooling. Moisture regain, absorption speed, wickability, water retenti on value, and water-vapor permeability were measured. In the wear trials that the subjects performed a subsequent exercise protocol wearing three differently treated socks in a conditioned environment ($14\pm2^{\circ}C$, 65$\pm$2% R.H.), microclimate temperature and humidity, and subjective wear sensations including thermal sensation, wettedness, softness, fit, and overall comfort were obtained. PEC-treated specimens with more than 20% add-on showed thermal storage on heating and thermal release on cooling by a DSC and the heat contents of treated ones were generally proportional to the add-ons. Moisture transport properties were highly improved after PEG treatment and increased rapidly with increasing add-on. The tendencies were, however, relaxed above 50% add-on and the treated knits were much stiffer above that add-on. In the wear trials of untreated, PEG add-on 20%, and 50% acrylic socks, the changes of microclimate temperature of 50% socks were significantly less than that of 20% socks. PEG add-on 50% socks showed significantly less changes of microclimate humidity than other two kinds of socks. Three kinds of socks showed significant differences in overall comfort and add-on 50% socks were accepted more comfortable than other two kinds of socks. Comfort zone of foot was extended after PEG treatment on socks and it implied that the subjects wearing PEG- treated socks felt comfortable in wider ranges of microclimate temperature and humidity.

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Risk Assessment of Soil through Earthworm Toxicity Test of Nonylphenol and Bisphenol A (Nonylphenol과 Bisphenol A의 지렁이 독성시험 및 토양 중 생태 위해성평가)

  • Lee Chul Woo;Park Soo Young;Yun Jun Heon;Choi Kyung Hee;Chung Young Hee;Kim Hyun Mi
    • Environmental Analysis Health and Toxicology
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    • v.20 no.4 s.51
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    • pp.279-286
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    • 2005
  • Earthworm (Eisenia fetida) acute toxicity test was carried out and ecological risk assessment in soil was performed with national monitoring data. 14 day - $LC_{50}$ of nonylphenol and bisphenol A were 288.1 mg/kg and 90.1 mg/kg, respectively. And NOECs of nonylphenol and bisphenol A were 250 mg/kg and 50 mg/kg, respectively. Significant weight decrement was appeared at 70 mg/kg of bisphenol A, however, nonylphenol at concentrations tested did not severe adverse effect on the weight decrement. The environmental monitoring has been carrying out by NIER since 1999. Exposure levels of nonylphenol in soil were ND$\sim$10.55 $\mu$g/kg and those of bisphenol A were ND$\sim$15.50$\mu$g/kg in National Monitoring data which had been performed from 2000 to 2004. The measured soil exposure level was applied to evaluate the environmental risk assessment. The values of PNEC for bisphenol A and nonylphenol were determined as 0.5 mg/kg and 2.5 mg/kg, respectively using the safety factors which were suggested in EU and OECD. The values of HQ (PEC/PNEC) were determined to be below I for bisphenol A and nonylphenol when the maximum exposure levels for bispheol A (15.50$\mu$g/kg) and nonylphenol (10.55$\mu$g/kg) were applied. Conclusively, the environmental risk assessment of bisphenol A and nonylphenol was not critical in soil.

Modeling the Fate of Priority Pharmaceuticals in Korea in a Conventional Sewage Treatment Plant

  • Kim, Hyo-Jung;Lee, Hyun-Jeoung;Lee, Dong-Soo;Kwon, Jung-Hwan
    • Environmental Engineering Research
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    • v.14 no.3
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    • pp.186-194
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    • 2009
  • Understanding the environmental fate of human and animal pharmaceuticals and their risk assessment are of great importance due to their growing environmental concerns. Although there are many potential pathways for them to reach the environment, effluents from sewage treatment plants (STPs) are recognized as major point sources. In this study, the removal efficiencies of the 43 selected priority pharmaceuticals in a conventional STP were evaluated using two simple models: an equilibrium partitioning model (EPM) and STPWIN$^{TM}$ program developed by US EPA. It was expected that many pharmaceuticals are not likely to be removed by conventional activated sludge processes because of their relatively low sorption potential to suspended sludge and low biodegradability. Only a few pharmaceuticals were predicted to be easily removed by sorption or biodegradation, and hence a conventional STP may not protect the environment from the release of unwanted pharmaceuticals. However, the prediction made in this study strongly relies on sorption coefficient to suspended sludge and biodegradation half-lives, which may vary significantly depending on models. Removal efficiencies predicted using the EPM were typically higher than those predicted by STPWIN for many hydrophilic pharmaceuticals due to the difference in prediction method for sorption coefficients. Comparison with experimental organic carbon-water partition coefficients ($K_{ocs}) revealed that log KOW-based estimation used in STPWIN is likely to underestimate sorption coefficients, thus resulting low removal efficiency by sorption. Predicted values by the EPM were consistent with limited experimental data although this model does not include biodegradation processes, implying that this simple model can be very useful with reliable Koc values. Because there are not many experimental data available for priority pharmaceuticals to evaluate the model performance, it should be important to obtain reliable experimental data including sorption coefficients and biodegradation rate constants for the prediction of the fate of the selected pharmaceuticals.

Effects of cultural conditions on growth of Micrococcus sp. and casein hydrolysis : (II) -Studies on patterns of casein hydrolysis with time during culture- (Micrococcus sp.의 생육 및 casein 분해에 미치는 배양조건의 영향 : (II) -배양시간에 따른 casein 분해 형태에 관한 연구-)

  • Lee, Si-Kyung;Pec, Un-Hua;Joo, Hyun-Kyu
    • Applied Biological Chemistry
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    • v.35 no.6
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    • pp.479-484
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    • 1992
  • This study was undertaken to determine the effects of cultural conditions on cell growth and casein hydrolysis for cell production in order to add Micrococcus sp. LL3 as a potential agent for industrial application with aim of shortening ripening period and improving flavor. Optimum temperature for cell growth and caseinolysis was $30^{\circ}C$ and $37{\circ}C$, respectively, and optimum pH was 7.0. The enzyme remained stable up to $50^{\circ}C$. Hydrolysis patterns of casein were also observed on SDS-PAGE. Both ${\alpha}-casein$ and ${\beta}-casein$ were totally hydrolysed by enzymes from Micrococcus sp. LL3 during culture. A preferential attack on ${\beta}-casein$ was observed. Production of aminopeptidase which cleaved polypeptides was the highest in early stationary phase during cell growth.

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Novel Polyurethane Binder for Propellant based on Hydroxyl-terminated Copolyether (폴리에테르 공중합체 디올(HTPE)을 사용한 새로운 추진제용 폴리우레탄 바인더)

  • Song Jong-Kwon;Pan Xiao;Lee Bum-Jae;Jeon Jun-Pyo;Hwang Gab-Sung
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2005.11a
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    • pp.417-421
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    • 2005
  • Novel two synthetic technics using cationic ring-opening copolymerization of tetrahydrofuran (THF) and ethylene oxide (EO), or just polymerized EO on Poly-THF, could lead to random hydroxyl-terminated poly(EO-ran-THF) or tri-block PEG-PTHF-PEC, respectively. These reactions were carried out using $BF_3O(C_2H_5)_2$ as catalyst, 1,4-butanediol or PTHF as diol initiator. Copolymer structures were controlled by monomer feed ratio, or initial PTHF and EO monomer added amount. The molecular weight of polymer was merely dependant on the ratio of [monomer]/[diol], but not on catalyst. Well-defined random and block hydroxyl-terminated copolyether was found to be as the prepolymer for the propellant binder from the experiment to polyurethane with them.

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Poly(Ethylene Glycol)-branched Polyethylenimine-poly(L-phenylalanine) Block Copolymer Synthesized by Multi-initiation Method for Formation of More Stable Polyelectrolyte Complex with Biotherapeutic Drugs

  • Park, Woo-Ram;Na, Kun
    • Journal of Pharmaceutical Investigation
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    • v.41 no.2
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    • pp.95-102
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    • 2011
  • An amphiphilic cationic branched methoxy poly (ethylene glycol)-branched polyethylenimine - poly(L-phenylalanine) (mPEG-bPEI-pPhe) block copolymer was successfully synthesized by ring-opening polymerization (ROP) of N-carboxyanhydride of L-phenylalanine (Phe-NCA) with mPEG-bPEI for the preparation of more stable polyelectrolyte complex (PEC) included a hydrophobic interaction. mPEG-bPEI was firstly prepared by the coupling of mPEG and bPEI using hexamethylene diisocyanate (HMDI). The structural properties of mPEG-bPEI-pPhe copolymers were confirmed by $^1H$ NMR. The copolymers exhibited a self-assemble behavior in water above critical aggregate concentration (CAC) in the range of 0.01-0.14 g/L. The CAC of copolymers obviously depended on the hydrophobic block content in the copolymers (the value decreased with the increase of the pPhe block content). The cationic copolymers have the ability to form multi-interaction complex (MIC) with bovine serum albumin (BSA) and plasmid DNA through multi-interaction (electrostatic and hydrophobic interaction). The physicochemical characterization of the complex was carried out by the measurement of zeta potential and particle size. Their zeta-potentials were positive (approximately +10 mV) and their sizes decreased with increasing pPhe contents in the copolymers (PPF/BSA wt% ratio = 2). The complex showed good stability at high ionic strength. Therefore, mPEG-bPEI-pPhe block copolymer was considered as a potential material to enhance the stability of complex including biotherapuetic drugs.

Design of Invisible Watermarking for Biometric Image of Electronic ID Card (전자신분증용 바이오 영상을 위한 비인지 워터마킹 설계)

  • Shin, Yong-Nyuo;Lee, Yong-Jun;Kim, Won-Gyum
    • Journal of Korea Multimedia Society
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    • v.11 no.11
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    • pp.1555-1565
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    • 2008
  • Biometric information such as face and fingerprint information is highlighted in many security areas, including authentication, due to its uniqueness and convenience factors. However, if exploited maliciously, it can cause more serious damage than traditional security measures, like passwords. This paper reviews the watermarking method that is able to verify the integrity of this biometric information. The watermark to be inserted is the date of the biometric information acquisition. It is combined with 16-bit Cyclic Redundancy Checks prior to insertion. In particular, face and fingerprint images are saved in a specific compressed format. The proposed watermarking algorithm will be designed in such a way as to remain resilient against compression. The watermark inserted at the acquisition stage will be extracted at each storage and deployment stage, so that the integrity of the biometric information can be verified.

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Vertical Distribution of Persistent Heavy metals in Core Sediments from Upo Wetland (자연습지 우포늪 퇴적물의 연도별 잔류성 중금속 축적도)

  • Lee, Chan Won;Boo, Min Ho;Jeon, Hong Pyo;Lim, Kyung Won;Kim, Ki Ho
    • Journal of Wetlands Research
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    • v.10 no.3
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    • pp.27-35
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    • 2008
  • Sediment cores were obtained from Upo and Mokpo in Upo Wetland and core samples were divided by depth into 20 ~ 21 subsamples. The heavy metal concentrations of Fe, Mn, Zn, AS, Cu, Cd, Ni, Pb, and Cr in the sediments of each depth were determined by ICP-MS. The texture of sediemnts from Upo Wetland appeared to be clayey silt with average grain size of $7.52{\sim}11.15{\mu}m$ for physical properties. It was found to have a clear tendency of depth profile with respect to TOC and ignition loss. Organics were stabilized in the range of 0.5 ~ 0.7 % TOC and 8 ~ 9 % ignition loss in 30 years, whereas, the surficial sediments have the highest concentrations of about 3.0 % of TOC and 13 ~ 15 % ignition loss. Those are much higher than the values of the main stream, the Nakdong River, which reflects the deposit of biodegradable organics from plants and other lifes. The vertical distribution of heavy metals in two sediment cores was investigated to elucidate historical trends of heavy metals deposited into Upo wetland. The depth profile concentrations of each heavy metal were compared and discussed with the Concensus-Based Sediment Quality Guidelines for freshwater ecosystems. All the Cd data for the vertical distribution in the sediments were detected above PEC value for Cd, which predict harmful effects on sediment-dwelling organisms expected to occur frequently. The concentrations of Zn, Cu, and Cr in all sediment samples for depth profile were detected below the TEC values, which provided a basis predicting the absence of toxicity by Zn, Cu, and Cr.

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A Study on the Organic/inorganic Composite Electrolyte Membranes for Dye Sensitized Solar Cell (염료감응형 태양전지를 위한 유기/무기 복합 전해질막에 대한 연구)

  • Koo, Ja-Kyung;Choi, Mi-Jung;Shin, Chun-Hwa;Kang, Tae-Un;Cho, Nam-Jun
    • Membrane Journal
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    • v.18 no.4
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    • pp.345-353
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    • 2008
  • Organic/inorganic composite electrolyte membranes were prepared for dye sensitized solar cell (DSSC). Polyethylene Glycol (PEG)s with various molecular weight (400, 600, 1,500 and 3,400) was ethoxysilated to fabricate organic/inorganic composite materials through sol-gel processes. The electrolyte membranes were produced by doping the composite materials with NaI and $I_2$, and their ionic conducting behavior was investigated. The ionic conductivity of the composite electrolyte was highly affected by the PEG molecular weight, and the highest conductivity was shown by the composite membrane prepared with PEG with the molecular weight of 1,500. The composite electrolyte membranes showed considerable improvement of ionic conductivity. Compared to PEO electrolyte membranes, the composite electrolyte membrane prepared by PEG, MW 1,500, showed much higher ionic conductivity.