• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.534-541
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• 2002

The use of triorganotins as insecticides, bacteriocides, and antifouling agents has increased dramatically over the past 30 years, In this paper, to evaluate the acute and chronic toxicity effects of various triorganotins (TBTO, TBTE, CTPT, TBTCI) on the growth of microalgae, Skeletonema costatum, we carried out the short term and long term experiments, respectively. In the short-term experiments, the growth of S. costatum was inhibited by the various triorganotins in the dose dependent manners, but recovered by the time laps. The growth inhibition of triorganotins were decreased in the groups with higher initial cell density. These data were resulted from the dilution effect and the biodegradation of triorganotins by the microalgae. In the long-term experiments, S. costatum died completely at the 1 $\mu$g/L of TBTP and CTPT, but didn't in short-term experiments. The facts suggest that the toxicity of the chronic exposure of triorganotins should be increased in the natural sea water with low phytoplankton density.

• Culinary science and hospitality research
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• v.5 no.2
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• pp.447-467
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• 1999

Most published work on product quality focuses on manufactured goods. The subject of service quality has received less attention. This distinction is important because some of the quality-improving strategies avaliable to manufacturers may be inappropriate for service firms. Services are performances, not objects. They are often produced in the presence of the customer, as in the cause of hotel restaurant services, quality occurs during service delivery, usually in an interaction between the customer and contact personnel of service firm. for this reason, service quality is highly dependent on the performance of employees, an organizational resource that cannot be controlled to the degree that components of tangible goods can be engineered. The study has begun as a basic study for customer satisfaction-oriented management in understanding the service quality of food & beverage products and through a systematic analysis of it. The major purpose of the study was to examine the relationship of the customer satisfaction and service quality in consideration of reliability, empathy, responsiveness, tangibility and assurance. An empirical research was conducted based on the previous theoretical studies. 286 customer at first class hotels in Seoul were selected as samples of this study. The time period of research was from February through March 1999, and answers were processed by SAS to yield frequency analysis, multivariate statistical analysis and regression analysis. The finding of the statistical treatment are frequencies, factor analysis, multiple regression analysis, path analysis. SERVQUAL method was used the service quality evaluation methods. After factor analysis, it was resulted to 3 factors. those were factor 1(assurance.empathy.responsiveness), factor 2(reliability), factor 3(tangibility). The findings of the statistical treatment are as follows. First, the attribute measurement of performance service quality was affected by customer satisfaction. Second, the attribute measurement of performance service qualify was affected by repurchase intention. Third, The attribute measurement of performance customer satisfaction was affected by repurchase intention. The result of study model was followed, service quality was affected repurchase intention than customer satisfaction. indirected effect through, service duality and customer satisfaction was affected repurchase intention.

• Journal of the Korean Ceramic Society
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• v.46 no.2
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• pp.200-210
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• 2009

It is necessary to minimize the mismatch of sintering shrinkage between dielectric ceramic and Ni inner electrode layers for the purpose of developing the ultra high-capacity multi layered ceramic condenser(MLCC). Thus, low temperature sintering of dielectric $BaTiO_3$ ceramic should be precedently investigated. In this work, the influence of the milling condition on sintering behavior and electrical properties of $BaTiO_3$ ceramics was investigated in the $BaTiO_3$(BT)-Mg-Dy-Mn-Ba system with borosilicate glass as a sintering agent. As milling time increased, specific surface area(SSA) of the powder increased linearly, while both sinterability and dielectric property were found to be drastically decreased with an increasing SSA. It was also revealed that the sinterability of the excessively milled $BaTiO_3$ ceramics could be recovered by increasing Ba content, rather than increasing glass addition. These results suggest that the sintering behavior of $BaTiO_3$ ceramics under the high SSA was more strongly dependent on the transient liquid phase caused by Ba addition, than the liquid phase from additional glass.

• Clinical and Experimental Reproductive Medicine
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• v.40 no.2
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• pp.67-75
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• 2013

Objective: To investigate the effect of peroxisome proliferator activated receptor ${\gamma}$(PPAR${\gamma}$) agonist on the cell proliferation properties and expression of human telomerase reverse transcriptase (hTERT) and aromatase in cultured endometrial stromal cell (ESC) from patients with endometriosis. Methods: Human endometrial tissues were obtained from women with endometriosis and healthy women (controls) using endometrial biopsy. Isolated ESCs were cultured and the cell proliferation was measured by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and expression of hTERT, aromatase, and cyclooxygenase (COX)-2 by western blotting according to the addition of rosiglitazone (PPAR${\gamma}$ agonist). Results: We demonstrate that the cultured ESCs of endometriosis showed hTERT protein overexpression and increased cellular proliferation, which was inhibited by rosiglitazone, in a dose-dependent manner. At the same time, PPAR${\gamma}$ agonist also inhibited aromatase and COX-2 expression, resulting in decreased prostaglandin $E_2$ production in the ESCs of endometriosis. Conclusion: This study suggests that PPAR${\gamma}$ agonist plays an inhibitory role in the proliferative properties of eutopic endometrium with endometriosis by down-regulation of hTERT and COX-2 expression; this could be a new treatment target for endometriosis.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.36 no.3
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• pp.221-226
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• 2010

A rare isoflavone, 7, 8, 4'-trihydroxyisoflavone, was isolated from a 10-year-old fermented soybean food. 7, 8, 4'-trihydroxyisoflavone was isolated for the first time from a Korean fermented soybean food. Evaluation tests of biological activity showed significantly inhibition activity for free radical scavenging on both non-enzymatic (DPPH system) and enzymatic method (xanthine oxidase system). DPPH radical scavenging effect of 7, 8, 4'-trihydroxyisoflavone was similar with vitamin C in a dose-dependent manner. In xanthine oxidase (XO) system 7, 8, 4'-trihydroxyisoflavone showed superoxide radical inhibition activity of 50 % at a concentration of $6.6{\pm}0.4\;{\mu}M$. Also, the compound significantly suppressed cellular MMP-1 formation. These results suggest that 7, 8, 4'-trihydroxyisoflavone could be developed as a potential preventive or therapeutic agent against skin aging.

• Journal of Ginseng Research
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• v.38 no.4
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• pp.233-238
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• 2014

Background: The actin cytoskeleton in podocytes is essential for the maintenance of its normal structure and function. Its disruption is a feature of podocyte foot-process effacement and is associated with proteinuria. ${\alpha}$-Actinin-4 in podocytes serves as a linker protein binding the actin filaments of the cytoskeleton. Methods: To investigate the effect of ginseng total saponin (GTS) on the pathological changes of podocyte ${\alpha}$-actinin-4 induced by diabetic conditions, we cultured mouse podocytes under normal glucose (5mM) or high glucose (HG, 30mM) conditions, with or without the addition of advanced glycosylation end products (AGE), and treated with GTS. Results: In confocal imaging, ${\alpha}$-actinin-4 colocalized with the ends of F-actin fibers in cytoplasm, but diabetic conditions disrupted F-actin fibers and concentrated ${\alpha}$-actinin-4 molecules at the peripheral cytoplasm. GTS upregulated ${\alpha}$-actinin protein in a time- and dose-dependent manner, and suppressed the receptor for AGE levels in western blotting. Diabetic conditions, including HG, AGE, and both together, decreased cellular ${\alpha}$-actinin-4 protein levels at 24 h and 48 h. Such quantitative and qualitative changes of ${\alpha}$-actinin-4 protein induced by diabetic conditions were mitigated by GTS. Conclusion: These findings imply that both HG and AGE have an influence on the distribution and amount of ${\alpha}$-actinin-4 in podocytes that can be recovered by GTS.

• Food Science and Preservation
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• v.9 no.2
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• pp.253-259
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• 2002

The antioxidative and free radical scavenging activity of water extracts of dandelion were investigated. Antioxidative and radical scavenging activity were assessed by means of different tests; inhibition of peroxidation on linoleic acid model system, scavenging DPPH radical, scavenging of hydroxyl radical by chemiluminescence assay, scavenging of superoxide anion radical by EPR spectroscopy and scavenging of hydrogen peroxide. The leaf extract showed strong antioxidant activity in linoleic acid system. The antioxidant activity of water extracts of dandelion increased with increasing concentrations of extracts. The scavenging activity of the dandelion extracts, on inhibition of the DPPH radical, was related to the reaction time. Hydroxyl radical were generated by lenten reaction and dandelion extract was found to scavenge OH˙in a concentration-dependent manner. The water extract of leaf had effective scavenging activities on hydrogen peroxide and superoxide anion radical. From the these data, it is evident that water extract of dandelion leaf is an effective scavenger for OH˙, O$_2$¨, DPPH˙, hydrogen peroxide. And, the antioxidative effect observed is believed to be partly due to this radical scavenger activity.

• Polymer(Korea)
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• v.32 no.1
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• pp.1-6
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• 2008

The adhesion behaviors and processability of NBR as a sealing material were investigated. In order to find the optimum formulation, the adhesive properties and processability were observed as the change of the contents of acrylonitrile (ACN) in NBR. Effects of Mooney viscosity, filler, plasticizer and crosslinking agent on the adhesion behaviors were also studied. The contents of ACN in NBR have great effects on adhesion behaviors and processability in NBR sealing. To know the optimum condition of roll mixing, degree of dispersion was investigated. It was confirmed that degree of dispersion was influenced by various factors such as mixing order, time, and temperature. The crosslinking system was studied as the observation of sulfur system, peroxide system, crosslinking density, and structure. From the variation of the dry condition and hexamine contents, the relation between adhesive and NBR was studied. These results show the adhesion properties and processability are dependent on the contents of ACN and crosslinking system.

• Korean Journal of Veterinary Research
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• v.45 no.2
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• pp.287-296
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• 2005

This experiments was designed to observe the effect of period and dose of ingestion of grapes on renal failure in dog. After the dogs had been mixed of general feed, raisins from U.S.A and fresh grapes from Chile selling in Korea. We observed the clinical sign, and analyzed the blood and urine using by biochemical test. The experiment was executed by the two following groups. The experiment group 1. derived renal failure by supplying the mixed general feed with fresh grapes and dry grapes 15 g per weight kg, 2 times a day (AM 09, PM 21), the experiment group 2. executed to derive renal failure by supplying the mixed general feed with fresh grapes and dry grapes 40 g per weight kg, 2 times a day. Extraction of blood for analysis was conducted one time a day and clinical test for renal failure was executed by means of a blood analysis, biochemical analysis, urine analysis, excretory urography (E.U) and E.R.D-$screen^{TM}$ urine test (Heska, USA). The results of group 1 were normal ranges (BUN 9.0~22.6 mg/dl, creatinine 0.8~1.2 mg/dl, Ca 9.7~12.3 mg/dl, Pi 2.9~4.6 mg/dl), renal failure was not observed. On the 3rd day in group 2, azotemia was arisen from the increasing BUN 83 mg/dl (7~25 mg/dl), creatinine 2.3 mg/dl (0.5~1.4 mg/dl), when executed urine was tested by E.R.D-$screen^{TM}$ test using in the early kidney disease diagnosis, microalbumine state was high positive, and it showed stale delay by using excretory urography (EU). This study demonstrated that acute renal failure by grapes and raisins dependent on food dose, and specific characters of individual.

• Journal of Korean Physical Therapy Science
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• v.11 no.3
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• pp.28-37
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• 2004

Background: Lumbar joint dysfunction is reported to be the main cause of lower back pain (LBP). The purpose of this study was to evaluate the effect of joint dysfunction on the postural balance of the lower hack and pelvis in different normal activities such as walking or stair management. Also it was studied whether the status of LBP (intensity and duration of LBP, length of treatment) contributes to die pelvic height difference (PHD) in various postures. Subjects: 28 patients with LBP and 32 normal adult volunteers, 60 years of age or younger, who came to the Community Health Center and orthopedic clinics in Incheon, South Korea. Methods: In order to determine the accuracy of the manual angulometer method in measuring the PHD, it was compared to the pelvic x-ray method in selected subjects. In the manual angulometer method, the arm of the angulometer was placed on the top of both iliac crests. The PHD was measured in static upright stance, then one-legged stance, on the affected leg or unaffected leg each time. Information regarding the disease status was obtained through interviews. Visual assessment scale was used to grade the intensity of LBP. Data analysis was performed using SPSS 10.0/PC program. Homogeneity between the two groups was tested by 2-test and t-test. To compare the PHD of the subgroups, we used t-test, F-test and two-way ANOVA. Relationships among dependent variables were analyzed by Pearson correlation analysis. Conclusion: In patients with LBP, lumbar joint dysfunction causes lumbar and pelvic postural asymmetry during normal activities.