• Restorative Dentistry and Endodontics
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• v.30 no.6
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• pp.493-504
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• 2005

This study was performed to investigate the compatibility between 4 dentin adhesives and 4 resin luting cements. Dentin adhesives used in this study were All-Bond 2 (Bisco Inc., Schaumbrug, IL, USA), Clearfil SE-Bond (Kuraray Medical Inc, Osaka, Japan), Prompt L-Pop (3M Dental Products, St. Paul, MN, USA), One-Up Bond F (Tokuyama corp., Tokyo, Japan) Resin luting cements used in this study were Choice (Bisco Inc., Schaumbrug, IL, USA), Panavia F (Kuraray Medical Inc, Osaka, Japan), RelyX ARC (3M Dental Products, St. Paul, MN, USA) Bistite II DC (Tokuyama corp., Tokyo, Japan). Combination of each dentin adhesive and corresponding resin cement was made to 16 experimental groups. Flat dentin surfaces was created on mid-coronal dentin of extracted mandibular third molars, then dentin surface was polished with 320-grit silicon carbide abrasive papers. Indirect resin composite block (Tescera, Bisco) was fabricated. Its surface for bonding to tooth was polished with silicon carbide abrasive papers Each dentin adhesive was treated on tooth surface and resin composite overlay were luted with each resin cement. Each bonded specimen was poured in epoxy resin and sectioned occluso-gingivally into 1.0mm thick slab, then further sectioned into $1.0{\times}1.0mm^2$ composite-dentin beams. Microtensile bond strength was tested at a crosshead speed of 1.0mm/min. The data were analysed by one-way ANOVA and Duncan's multiple comparison tests The results of this study were as follows, 2-step self-etching dentin adhesive which has additional bonding resin is more comparison than tests. self-etching dentin adhesive.

• Journal of The Korean Association For Science Education
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• v.42 no.1
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• pp.111-125
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• 2022

This study aims to investigate the effects of the ENACT project on promoting pre-service science teachers (PSTs)' views on the social responsibility of scientists and engineers. The ENACT project was designed to cultivate the social responsibility by integrating the theoretical framework of socioscientific issues (SSIs) education with problem-based inquiry approaches for the resolution of the issues. Thirty-two PSTs voluntarily participated in the project and completed the five stages over three months. Data was collected through a questionnaire to measure PSTs' view of the social responsibility of scientists and engineers (VSRoSE) and focus-group interviews. Results indicate that the PSTs presented statistically significant changes in their views of the social responsibility after the ENACT project. The mean scores of the five sub-dimensions of VSRoSE significantly increased. The interviews also supported that the PSTs had opportunities to seriously consider the social responsibility of scientists and engineers through epistemological exploration of science and technology (Cycle I), and problem-solving and action-taking (Cycle II). In particular, they agreed more on such responsibilities as consideration of societal needs and demands, pursuit of the common good, civic engagement and services using their expertise, communications with the public regarding potential risks, and participation in policy decision-making related to science and technology advances. Educational implications for SSI education and teacher education were suggested.

• Tuberculosis and Respiratory Diseases
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• v.82 no.2
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• pp.133-142
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• 2019

Background: Idiopathic pulmonary fibrosis involves irreversible alveolar destruction. Although alveolar epithelial type II cells are key functional participants within the lung parenchyma, how epithelial cells are affected upon bleomycin (BLM) exposure remains unknown. In this study, we determined whether BLM could induce cell cycle arrest via regulation of Schlafen (SLFN) family genes, a group of cell cycle regulators known to mediate growth-inhibitory responses and apoptosis in alveolar epithelial type II cells. Methods: Mouse AE II cell line MLE-12 were exposed to $1-10{\mu}g/mL$ BLM and $0.01-100{\mu}M$ baicalein (Bai), a G1/G2 cell cycle inhibitor, for 24 hours. Cell viability and levels of pro-inflammatory cytokines were analyzed by MTT and enzyme-linked immunosorbent assay, respectively. Apoptosis-related gene expression was evaluated by quantitative real-time reverse transcription-polymerase chain reaction (qRT-PCR). Cellular morphology was determined after DAPI and Hoechst 33258 staining. To verify cell cycle arrest, propidium iodide (PI) staining was performed for MLE-12 after exposure to BLM. Results: BLM decreased the proliferation of MLE-12 cells. However, it significantly increased expression levels of interleukin 6, tumor necrosis factor ${\alpha}$, and transforming growth factor ${\beta}1$. Based on Hoechst 33258 staining, BLM induced condensation of nuclear and fragmentation. Based on DAPI and PI staining, BLM significantly increased the size of nuclei and induced G2/M phase cell cycle arrest. Results of qRT-PCR analysis revealed that BLM increased mRNA levels of BAX but decreased those of Bcl2. In addition, BLM/Bai increased mRNA levels of p53, p21, SLFN1, 2, 4 of Schlafen family. Conclusion: BLM exposure affects pulmonary epithelial type II cells, resulting in decreased proliferation possibly through apoptotic and cell cycle arrest associated signaling.

• Analytical Science and Technology
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• v.9 no.3
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• pp.253-261
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• 1996

Analytical method for the determination of trace germanium in inorganic matrices by differential pulse polarography(DPP) was studied. The reduction peak of germanium(IV) in perchloric acid solution containing 1, 2, 3-trihydroxy benzene appeared at -0.45V(vs. Ag/AgCl) and the peak current for germanium complex varied linearly with concentration variation. Factors affecting sensitivity and precision for germanium quantification were studied and detection limit under the investigated parameters was 1ng/ml. Inorganic samples were decomposed by fusion with potassium pyrosulfate. Serious interferences of Se(IV), Pb(II), As(III) for the determination of germanium were discussed. Interferences of these elements could be avoided by extraction of germanium from decomposed matrices by $CCl_4$ in 10M HCl solution. The germanium contents of inorganic samples(Pb bf. dust, Cu bf. dust, gneiss, Cu anode slime) were determined by the above method.

• Journal of Korean Medicine for Obesity Research
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• v.4 no.1
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• pp.67-80
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• 2004

Objectives: Obesity is a growing epidemic with subsequent health consequences leading not only to reduced quality of life but also to increased medical costs. Recently nutritional balances are emphasized in the field of obesity, and especially maintaining proper equilibriums of minerals. The correlation of minerals obtained from the method of HTMA(Hair Tissue Mineral Analysis) with obese degree has not been studied in Korea yet. We studied any significant difference of mineral concentrations and components according to the obese degree. Methods: 78 subjects were analyzed who visited Garosero clinic of oriental medicine to lose their weight from June to November 2004. We used BMI(Body Mass Index), PBF(Percent Body Fat), WHR(Waist-Hip Ratio) and abdominal circumference obtained by bio-electrical impedance analysis as an obese degree. And we analyzed correlation with mineral concentrations and ratios obtained from HTMA. Results & Conclusion: 1. Na, K, Zn, Se had significant correlation with obese degree in case of nutritional minerals from HTMA. Especially, K had high significance. 2. Toxic minerals from HTMA had no significance with obese degree. 3. Rb had significant correlation with obese degree in case of additional minerals from HTMA. 4. Among important ratios from HTMA, Na/K had significant correlation with obese degree, but Ca/K had correlation except PBF, and Na/Mg had correlation except WHR. 5. Among toxic ratios from HTMA, Se/Hg had significant correlation with obese degree, but S/Hg had correlation except BMI. 6. Na, K, Zn, Rb, Na/K, Ca/K had significant differences between obesity groups classfied by BMI. Ob II group had sinificant difference from NW group in cases of K, Zn, Rb, Na/K, and Ob II group had sinificant difference from OW group in case of Ca/K.

• Journal of the Korean earth science society
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• v.33 no.6
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• pp.534-543
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• 2012

The relationship between tectonic uplift and geophysical analysis of gravity anomalies and the in-situ stress fields in the Otway Ranges, SE Australia is addressed in this study to understand the nature and possible mechanism for the neotectonic movements. The uplift axis of the ranges is coincident with the regional Bouguer gravity highs whereas thick Tertiary sedimentary successions are highly correlated with the gravity lows along the basin rift geometry. This result suggests that the gravity highs are separated by the thick Tertiary sedimentary successions. Regional structural trends associated with faults and foldings of the deformed surfaces are consistent with the prevailing NW-SE $S_{Hmax}$ trend in this part of the continent. The anomalously positive correlation between topography and Bouguer gravity fields suggests possibly a lithospheric flexural deformation mode at a long wavelength (order of $10^2$ kms) in the region. It also suggests that the reactivation of pre-existing lithospheric structures driven by plate boundary forces plays a key role in this mode.

• Journal of the Korean Chemical Society
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• v.31 no.3
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• pp.236-243
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• 1987

The optimum resolution condition of 11 organophosphorus pesticides by gas-liquid chromatography was studied using a capillary column. The injection modes and types of vaporization tubes were evaluated in relation to pesticide analysis. The best reproducibility of peak heights of pesticides was obtained by the split mode with the vaporization tube packed with quartz wool. A 25m SE-30 capillary column provided better resolution than SE-54 column for their optimum resolution. The column at $200^{\circ}C$ initially was heated by $5^{\circ}C/min\;to\;230^{\circ}C$ followed by $10^{\circ}C/min\;to\;270^{\circ}C$ and the temperatures were held constant for 5 minutes at $230^{\circ}C\;and\;270^{\circ}C$, respectively. The relative standard deviations of their retention times were less than 0.19%.

• Journal of the Korean Society of Physical Medicine
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• v.3 no.3
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• pp.193-202
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• 2008

Purpose : This study was performed for effects of intervention of mat & ball exercise, sling exercise, and general intervention. The purpose of this study was to know influenced on the change of Oswestry back pain disability index (OBPDI) with chronic low back pain(CLBP) patients. Methods : Three groups of CLBP patients(n=53) were allocated randomly in this study experimental group I (mat & ball exercise group MBE, n=18), experimental group II(sling exercise group SE, n=18) and control group(general intervention, n=17). Intervention was provided 6 weeks(S days a week). Experimental group was provided 3 set a day(10 time/ 1 set, 10sec holding and 10sec resting/ 1 time). The following was the result of the data analysis about OBPDI experiment that had been carried on a week, 2 weeks, 3 weeks, 4 weeks, S weeks, 6 weeks after, and even comparing with pre-experimental state. Results : The results were as follows. OBPDI about intervention period had decrease in the MBE and the SE groups. but there was no difference in the control group. Among three groups, The MBE and the SE groups had difference compare with control group. This shows that the MBE and the SE groups had effective decrease pain and disability. Conclusion : Therefore, this study shows that trunk stabilization exercise program influenced on the change of OBPDI with CLBP patients.

• Animal Bioscience
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• v.35 no.4
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• pp.567-576
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• 2022

Objective: An experiment was conducted to determine the effect of algae-based antioxidant containing Se yeast (EconomasE^®) on the growth performance, visceral organ weight, meat quality, and oxidative stability of broiler chickens. Methods: Nine hundred sixty, day-old male broiler chickens (Cobb, 43.97±0.55 g) were divided into three dietary treatments and allocated into 12 deep litter pens in a completely randomized design giving 4 replicate cages for each treatment. Three dietary treatments were: i) control (CON, basal diet with sufficient nutrient), ii) vitamin E (VitE, basal diet supplemented with 100 IU VitE), and iii) Algae-based antioxidant containing Se yeast (EcoE, basal diet supplemented with 0.2% algae-based antioxidant containing Se yeast: EconomasE^®). Maize soybean meal based basal diets were formulated to meet or exceed the nutrition requirement for broiler chickens. Chickens were fed ad-libitum experimental diets during the 42 days experiment period. On days 21 and 42, body weight and feed intake were measured to calculate the feed conversion ratio of the chickens. Intestine and visceral organs were measured together with meat quality and oxidative stability on days 14 and 42. Results: Chickens fed with EcoE showed improved (p<0.05) growth performance, meat quality, and higher (p<0.05) oxidative stability compared to the chicken fed on CON. Moreover, broiler chickens fed with EcoE showed similar (p<0.05) growth performance with better (p<0.05) meat quality and higher oxidative stability compared to the broiler chickens fed VitE (p<0.05). Conclusion: The algae-based antioxidant containing Se yeast can be supplemented into commercial broiler diets as a substitution of VitE while maintaining growth performance with enhancing meat quality and oxidative stability of the broiler chickens.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.8
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• pp.930-937
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• 2007

Korean pine(Pinus densiflora) bark was evaluated for its adsorption capacity of Cu(II) ions from aqueous solution by running a series of batch experiments. Prior to the tests, the milled barks were treated with 1 N NaOH or 1 N HCl to examine the effect of surface modification. For comparison, untreated bark was tested under same condition. Within the tested pH range between 3 and 6, NaOH treatment increased Cu(II) adsorption capacity by $139\sim184%$, while HCl treatment decreased it by $37\sim42%$. Maximum copper ion uptake by bark was observed at pH $5\sim6$, but pH of solution was not a potent influence. A pseudo second-order kinetic model fitted well for the sorption of copper ion onto bark. For NaOH-treated bark, the calculated sorption capacity$(q_e)$ increased from 6.58 to 12.77 mg/g, while the equilibrium rate constant$(k_2)$ decreased from 0.284 to 0.014 g/mg/min as initial Cu(II) concentration doubled from 100 mg/L. A batch isotherm test using NaOH-treated bark showed that equilibrium sorption data were represented by both the Langmuir model and the Freundlich model. It was confirmed that carboxylic acid of bark was involved in the Cu(II) adsorption. For NaOH-treated bark, in particular, carboxylate ion produced by hydrolysis or saponification appeared to be a major functional roup responsible for the enhanced Cu(II) sorption.