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Effects of the Pilose Antler on the Experimental Hepatocarcino- genesis and the Natural Killer Cell Activity in Rats (랫드의 실험적 간암발생과 자연살해세포의 활성에 미치는 녹용의 효과)

  • 정자영;길광섭;이영순
    • Toxicological Research
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    • v.14 no.4
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    • pp.475-481
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    • 1998
  • This study was performed to investigate the modifying effect of the general (GPA) and the fermented pilose antler (FPA) on experimental hepatocarcinogenesis and Natural Killer cell activity in rats. Specific pathogen free, 5-week male Sprague-Dawley rats were divided into four groups. To induce hepatocarcinogenesis, diethylnitrosamine (DEN, 200 mg/kg, i.p.) was used as a tumor initiator and was given in a single dose at experimental onset. All rats were given a partial hepatectomy (PH) at 3 weeks after experimental onset. Sodium phenobarbital (PB, 0.05% in diet), GPA (0.075% in diet) and FPA (0. 075% in diet) were given from 2 to 8 weeks. Group I of the initiation control group was only given DEN. As initiation-promotion group, Group II was given DEN and then PB. Group III and IV were given DEN-PB-GPA and DEN-PB-FPA, respectively. In hematological analysis, as compared with Group I. the number of white blood cells were significantly increased in the GPA (p<0.01) and the FPA treated group (p<0.05), respectively. Natural killer (NK) cell activity by flow cytometer (FCM) analysis was higher in group of treated with the GPA (35%) than that of the FPA (27.5%), but not significant. Result of the immunohistochemical staining of the glutathione S-transferase placental form (GST-p) indicated that the number of and area of the pre-neoplastic lesions was not significantly changed in Group III and IV compared Group II, respectively. In conclusion, the GPA and the FPA treatment significantly increased the number od WBC in peripheral blood, but the enhancing NK activity and the modifying effect on the experimental hepatocarcinogenesis were not observed.

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Research on the Perception of Wedding Planners on Hanbok as a Wedding Ceremony Dress

  • Shin, Kyeong-Seub
    • Journal of Fashion Business
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    • v.14 no.6
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    • pp.84-99
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    • 2010
  • The aim of this study is to understand the wedding planners' general perceptions on Hanbok as a ceremonial dress in wedding ceremonies. Moreover, the study explores the aesthetic understanding of wedding planners on Hanbok which both influences their choice of recommendation and purchasing decisions. In the process of organizing the structure of weddings for clients, planners have naturally acquired the position of being able to influence the sales of the Hanbok industry. Moreover, brides-to-be are heavily dependant on wedding planners in sketching the outlines of their whole wedding. Therefore, in order to analyze the opinions of both subjects, a research survey was launched which involved three hundred participants from two groups: first, wedding planners who were free lancers working in the Chungdam District, and second, wedding planners who were working for wedding consulting firms. The survey method was based on one precedent study, in which a preliminary survey was conducted by interviewing companies in the Hanbok industry and wedding consulting firms, and an additional survey in the form of questionnaires. The STATA 11.0 program was used for analyzing the recruited data for frequency analysis and cross-tabulations analysis on career. The conclusion of this research may be used as substantial preliminary data in prospering the Hanbok industry, enhance and newly shape its marketing strategies and the conclusion is as follows. 1. Wedding planners have a more profound understanding on Hanbok and prioritize the significance of formative constituents in the order of color, material, style, size, and decoration. 2. The prospects of promoting the image of Hanbok through wedding planners is promising. According to surveys, this goes to show that the persuasion of wedding planners have brought a positive effect on choice of Hanbok and as wedding planners become more specialized, their involvement in preparing Hanbok with brides is increasing. 3. Wedding planners believed that the main reasons why future brides do not select Hanbok as a ceremony dress are that the cost is too high relative to practicality and that there are not enough opportunities to wear them.

Effects of Dietary Prosomillet on cholesterol and Fatty Acid Metabolism in Rats Fed High Cholesterol Diets

  • Cho, Sung-Hee;Jung, Seung-Eun;Lee, Hye-Kyung;Ha, Tae-Youl
    • Nutritional Sciences
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    • v.3 no.1
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    • pp.25-30
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    • 2000
  • To study the effect of prosomillet (Panicum milaceum) on lipid metabolism, male Sprague-Dawley rats weighing 190$\pm$8g were fed six experimental diets for four weeks. The six diets based on AIN-76 composition consisted of one cholesterol-free(normal) and five 1%(w/w) cholesterol diets, i.e. control, two diets containing additional 0.3 and 0.6%(w/w) methanol extracts of prosomillet and another two diets containing 15 and 30% (w/w) prosomillet powder. There was no difference in weight gains between the groups but relative liver weights increased under the cholestrol diets. Plasma levels of total cholesterol and triglyceride(TG) decreased by 23-27% and by 37-52%, respectively, in the four prosomillet diet groups compared to those of the normal and control groups. Whereas in the liver, only TG levels decreased in the prosomillet diet groups. Fecal excretions of bile acid and cholesterol significantly with methanol extracts of prosomillet. There was a significant increase in the activity of hepatic microsomal cholesterol 7$\alpha$-hydroxylase when feeding 1% cholesterol but prosomillet in the diet, either as in the form of powder or methanol extract, appeared to have only slight additional effects, namely increases in enzyme activity. The activity of liver cytosolic glucose-6-phophate dehydrogenase (G6PDH) tended to be reduced with high cholesterol diets and dropped markedly by 15% using additional prosomillet powder. Those of the liver cytoxolic malic enzyme had a similar tendency to those of G6PDH. The results indicate that certain active components in prosmillet other than fiber have the potential to exert hypolipidemic effects via regulating cholesterol excretions and lipogenesis.

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Studies on the Synthesis and Surface Active Properties of N-carboxybetaine Derivatives Containing Amide Bond (Amide 결합(結合)을 가진 N-carboxybetaine류(類)의 합성(合成)과 그 계면활성(界面活性))

  • Lee, Dong-Woo;Lee, Hi-Jong;Kim, Yong-In
    • Journal of the Korean Applied Science and Technology
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    • v.8 no.2
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    • pp.115-122
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    • 1991
  • Four novel amphoteric surfactants of N-(2-alkylamidoethyl)-N, N-dimethyl ammonioacetates were synthesized. The each reaction between four saturated fatty acids containing 10, 12, 14 and 16 carbon atoms and N, N-dimethylethylene diamine permitted to give the intermediate products, N-(2-alkylamidoethyl)-N, N-dimethylamines. Quaterinzation of these intermediates was permitted to form N-(2-alkylamidoethyl)-N, N-dimethyl, ammonioacetates, whose sturctures were identified by CC, TLC, elemental analysis, IR pectrophotometry and $^1$HNMR spectrometry. The products yielded from 48% to 58%. The isoelectric points were shown in the range of $4.30{\sim}6.64$. It showed a tendency to learn to the acidic site and its range was broadened as increase of the hydrophobic group length. Surface tensions of the aqueous solution in the $10^{-6}{\sim}10^{-1}$mol/l of amidobetaines were measured. and the critical micell concentration(cmc) were shown in the range of $8.37{\times}10^{-6}{\sim}8.96{\times}10^{-2}$mol/l, and ${\Gamma}_{cmc}$ were reduced to 32.3~38.2 dyne/cm. A linear relationship between log cmc and the number of carbon in the hydrophobic alkyl chain was presented by the formula of log cmc=2.38-0.5n, and the contribution-rate of n on the standard free energy change in micellization ${\partial}({\Delta}G^0$$_m)/{\partial}n$, was calulated as -0.5RT.

Diabetic Atherosclerosis and Glycation of LDL(Low Density Lipoprotein)

  • Park, Young-June;Kim, Tae-Woong
    • Preventive Nutrition and Food Science
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    • v.1 no.1
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    • pp.134-142
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    • 1996
  • Diabetes carries an increased risk of atherosclerotic disease that is not fully explained by known car-diovascular risk factors. There is accumulating evidence that advanced glycation of structural proteins, and oxidation and glycation of circulating lipoproteins, are implicated in the pathogenesis of diabetic ather-osclerosis. Reactions involving glycation and oxidation of proteins and lipids are believed to contribute to atherogenesis. Glycation, the nonenzymatic binding of glucose to protein molecules, can increase the ather-ogenic potential of certain plasma constituents, including low density lipoptotein(LDL). Glycation of LDL is significant increased in diabetic patients compared with normal subjects, even in the presence of good glycemic control. Metabolic abnormalities associated with glycation of LDL include diminished recognition of LDL by the classic LDL receptor; increased covalent binding of LDL in vessel walls ; enhanced uptake of LDL by the macrophages, thus stimulating foam cell formation ; increased platelet aggregation; formation of LDL-immune complexes ; and generation of oxygen free radicals, resulting on oxidative damage to both the lipid and protein components of LDL and to any nearby macromolecules. Oxidized lipoproteins are characterzied by cytotoxicity, potent stimulation of foam cell formation by macrophages, and procoagulant effects. Combined glycation and oxidation, "glycoxidation" occurs when oxidative reactions affect the initial products of glycation, and results in irreversible structural alterations of proteins. Glycoxidation is of greatest significance in long lived proteins such as collagen. In these proteins, glycoxidation products, believed to be atherogenic, accumulate with advancing age : in diabetes, their rate of accumulate is accelerated. Inhibition of glycation, oxidation and glycoxidation may form the basis of future antiaterogenic strategies in both diabetic and nondiabetic individuals.dividuals.

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A Simple $H\ddot{u}ckel$ Approach to Intramolecular Photocyclization Reaction of N-(2-Chlorobenzyl)-Pyridinium, N-(Benzyl)-2-Chloropyridinium, and N-(2-Chlorobenzyl)-2-Chloropyridinium Salts

  • Lee, Gang-Ho;Park, Yong-Tae
    • Bulletin of the Korean Chemical Society
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    • v.15 no.10
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    • pp.857-860
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    • 1994
  • We have calculated the ${\pi}$-electron density, atom self-polarizability, and free valence on each atom of N-(2-chlorobenzyl)-pyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-2-chloropyridinium salts using a simple Huckel method in order to discuss their intramolecular photocyclization reaction in a qualitative method. Our calculation qualitatively predicts that photocyclization occurs through forming radicals as a reaction intermediate by breaking a C-Cl bond after photoexcitation into a triplet state via intersystem crossing from an initially excited singlet state. We noticed that this C-Cl bond breaking is aided by ${\pi}$-complex formation between a chlorine atom and the ${\pi}$ -electrons of the neighboring ring in the triplet state and a stronger ${\pi}$-complex bond makes C-Cl bond breaking, i.e., radical formation, much easier. A chlorine atom will form a stronger ${\pi}$ -complex bond to a benzyl ring of N-(benzyl)-2-chloropyridinium than a pyridinium ring of N-(2-chlorobenzyl)-pyridinium because the former can donate its ${\pi}$-electron more easily than the latter. The chlorine at position 15 of N-(2-chlorobenzyl)-2-chloropyridinium salt in the excited state also provides its ${\pi}$-electron to the benzyl ring. So this ${\pi}$-electron can increase the bond strength of the $\pi-complex.$ Therefore, the strength of ${\pi}$-complex follows the order of N-(2-chlorobenzyl)-2-chloropyridinium, N-(benzyl)-2-chloropyridinium, and N-(2-chlorobenzyl)-pyridinium salts and thus the radical formation rate. This provides us with an intramolecular photocyclization reaction rate of the same order as given above.

Changes in Phosphorus and Sediment Oxygen Demand in Coastal Sediments Promoted by Functionalized Oyster Shell Powder as an Oxygen Release Compound

  • Kim, Beom-geun;Khirul, Md Akhte;Cho, Dae-chul;Kwon, Sung-Hyun
    • Journal of Environmental Science International
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    • v.28 no.10
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    • pp.851-861
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    • 2019
  • In this study, we performed a sediment elution experiment to evaluate water quality in terms of phosphorus, as influenced by the dissolved oxygen consumed by sediments. Three separate model column treatments, namely, raw, calcined, and sonicated oyster shell powders, were used in this experiment. Essential phosphorus fractions were examined to verify their roles in nutrient release from sediment based on correlation analyses. When treated with calcined or sonicated oyster shell powder, the sediment-water interface became "less anaerobic," thereby producing conditions conducive to partial oxidation and activities of aerobic bacteria. Sediment Oxygen Demand (SOD) was found to be closely correlated with the growth of algae, which confirmed an intermittent input of organic biomass at the sediment surface. SOD was positively correlated with exchangeable and loosely adsorbed phosphorus and organic phosphorus, owing to the accumulation of unbound algal biomass-derived phosphates in sediment, whereas it was negatively correlated with ferric iron-bound phosphorus or calcium fluorapatite-bound phosphorus, which were present in the form of "insoluble" complexes, thereby facilitating the free migration of sulfate-reducing bacteria or limiting the release from complexes, depending on applied local conditions. PCR-denaturing gradient gel electrophoresis revealed that iron-reducing bacteria were the dominant species in control and non-calcined oyster shell columns, whereas certain sulfur-oxidizing bacteria were identified in the column treated with calcined oyster powder.

Composite PEO-Coatings as Defence Against Corrosion and Wear: A Review

  • Gnedenkov, S.V.;Sinebryukhov, S.L.;Sergienko, V.I.;Gnedenkov, A.S.
    • Corrosion Science and Technology
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    • v.18 no.5
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    • pp.212-219
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    • 2019
  • This paper reviews recent approaches to develop composite polymer-containing coatings by plasma electrolytic oxidation (PEO) using various low-molecular fractions of superdispersed polytetrafluoroethylene (SPTFE). The features of the unique approaches to form the composite polymer-containing coating on the surface of MA8 magnesium alloy were summarized. Improvement in the corrosion and tribological behavior of the polymer-containing coating can be attributed to the morphology and insulating properties of the surface layers and solid lubrication effect of the SPTFE particles. Such multifunctional coatings have high corrosion resistance ($R_p=3.0{\times}10^7{\Omega}cm^2$) and low friction coefficient (0.13) under dry wear conditions. The effect of dispersity and ${\xi}$-potential of the nanoscale materials ($ZrO_2$ and $SiO_2$) used as electrolyte components for the plasma electrolytic oxidation on the composition and properties of the coatings was investigated. Improvement in the protective properties of the coatings with the incorporated nanoparticles was explained by the greater thickness of the protective layer, relatively low porosity, and the presence of narrow non-through pores. The impedance modulus measured at low frequency for the zirconia-containing layer (${\mid}Z{\mid}_{f=0.01Hz}=1.8{\times}10^6{\Omega}{\cdot}cm^2$) was more than one order of magnitude higher than that of the PEO-coating formed in the nanoparticles-free electrolyte (${\mid}Z{\mid}_{f=0.01Hz}=5.4{\times}10^4{\Omega}{\cdot}cm^2$).

Conceptual Design of Small WIG Craft (소형 위그선 개념 설계)

  • Shin, Myung-Soo;Kim, Yoon-Sik;Lee, Gyeong-Joong;Kang, Kuk-Jin;Park, Young-Ha;Lee, Young-yeon
    • Journal of the Society of Naval Architects of Korea
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    • v.43 no.1 s.145
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    • pp.134-146
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    • 2006
  • This paper presents the primary conceptual design results of twenty-passenger class Wing-In-Ground(WIG) effect craft. As a first step, top level requirements were proposed and principal dimensions were determined. Maximum speed in ground effect condition is 150 km/h with two tons payload including passengers. Total weight is estimated as 8.5 tons with 2 tons of thrust. Hull and airfoil sections were designed and self propulsion tests were performed by radio controlled model. Two planing hull forms with the transom stern were proposed and towing tests were performed. The resistance and running attitude were measured and the feasibility is checked for the prototype hull form of the twenty-passenger class WIG craft. The free running tests show the stable smooth running attitude at designed speed. Also this radio controlled model can take off around 0.15 meter wave height. It can be said that the top level requirement for the twenty passenger class WIG ship is satisfied successfully. The design optimization to increase the transport efficiency and safety will be performed in the near future.

Hybrid RANS and Potential Based Numerical Simulation for Self-Propulsion Performances of the Practical Container Ship

  • Kim, Jin;Kim, Kwang-Soo;Kim, Gun-Do;Park, Il-Ryong;Van, Suak-Ho
    • Journal of Ship and Ocean Technology
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    • v.10 no.4
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    • pp.1-11
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    • 2006
  • The finite volume based multi-block RANS code, WAVIS developed at MOERI is applied to the numerical self-propulsion test. WAVIS uses the cell-centered finite volume method for discretization of the governing equations. The realizable $k-{\epsilon}$ turbulence model with a wall function is employed for the turbulence closure. The free surface is captured with the two-phase level set method and body forces are used to model the effects of a propeller without resolving the detail blade flow. The propeller forces are obtained using an unsteady lifting surface method based on potential flow theory. The numerical procedure followed the self-propulsion model experiment based on the 1978 ITTC performance prediction method. The self-propulsion point is obtained iteratively through balancing the propeller thrust, the ship hull resistance and towing force that is correction for Reynolds number difference between the model and full scale. The unsteady lifting surface code is also iterated until the propeller induced velocity is converged in order to obtain the propeller force. The self-propulsion characteristics such as thrust deduction, wake fraction, propeller efficiency, and hull efficiency are compared with the experimental data of the practical container ship. The present paper shows that hybrid RANS and potential flow based numerical method is promising to predict the self-propulsion parameters of practical ships as a useful tool for the hull form and propeller design.