• Development and Reproduction
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• v.10 no.3
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• pp.197-202
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• 2006

Sex steroids are generally considered as natural sex inducers in fish, and aromatase (cytochrome P450 aromatase) that catalyzes androgens into estrogens in the steroidogenic pathway is also known to be involved in sex differentiation. The timing of aromatase action is, thus, of central importance in the study of fish sex differentiation. We treated sexually undifferentiated tilapia (Oreochromis niloticus) larvae with $Fadrozole^{TM}$, a non-steroidal aromatase inhibitor (AI), by immersing the fish in a solution containing AI during the sex differentiation period to narrow down the critical period of aromatase action. Fish were treated once at 11 or 13 days post fertilization (dpf), or twice at 11 and 13 dpf. The concentrations of AI at each time of the treatment were 0 mg/L (control), 50 mg/L or 100 mg/L. Survival rate was not statistically associated with AI immersion treatment (p>0.25). However, sex ratio was significantly altered by the treatment, with higher concentration and double immersion being more effective in masculinizing genetic females (p<0.05). These results suggest that aromatase action for sex differentiation in this fish species would begin at least from 11 dpf which is much earlier than previously expected, and that only 3 hours of brief immersion in AI solution is powerful enough to alter genetically programed sex.

• Journal of Microbiology and Biotechnology
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• v.22 no.12
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• pp.1659-1664
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• 2012

TSAHC [4'-(p-toluenesulfonylamido)-4-hydroxychalcone] is a promising antitumorigenic chalcone compound, especially against TM4SF5 (four-transmembrane L6 family member 5)-mediated hepatocarcinoma. We evaluated the potential of TSAHC to inhibit the catalytic activities of nine cytochrome P450 isoforms and of P-glycoprotein (P-gp). The abilities of TSAHC to inhibit phenacetin O-deethylation (CYP1A2), coumarin 6-hydroxylation (CYP2A6), bupropion hydroxylation (CYP2B6), amodiaquine N-deethylation (CYP2C8), diclofenac 4-hydroxylation (CYP2C9), omeprazole 5-hydroxylation (CYP2C19), dextromethorphan O-demethylation (CYP2D6), chlorzoxazone 6-hydroxylation (CYP2E1), and midazolam 1'-hydroxylation (CYP3A) were tested using human liver microsomes. The P-gp inhibitory effect of TSAHC was assessed by [$^3H$]digoxin accumulation in the LLCPK1-MDR1 cell system. TSAHC strongly inhibited CYP2C8, CYP2C9, and CYP2C19 isoform activities with $K_i$ values of 0.81, 0.076, and $3.45{\mu}M$, respectively. It also enhanced digoxin accumulation in a dose-dependent manner in the LLCPK1-MDR1 cells. These findings indicate that TSAHC has the potential to inhibit CYP2C isoforms and P-gp activities in vitro. TSAHC might be used as a nonspecific inhibitor of CYP2C isoforms based on its negligible inhibitory effect on other P450 isoforms such as CYP1A2, CYP2A6, CYP2B6, CYP2D6, CYP2E1, and CYP3A.

• Restorative Dentistry and Endodontics
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• v.24 no.2
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• pp.381-391
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• 1999

A new 5th generation adhesive system(ONE-STEP) has been supplied which operators can apply to conditioned tooth surfaces by one simplified step. The purpose of this study was to determine whether different methods of adhesive application and various air drying duration after applying adhesive affect the shear bond strength of composite resin to dentin, and to evaluate the adhesive pattern of composite resin and dentin under SEM. Seventy-seven extracted human molar teeth were cleaned and mounted in palstic test tubes. The occlusal dentin surfaces were exposed with Diamond Wheel Saw and smoothed with Lapping and Polishing Machine (South Bay Technology Co., U.S.A.). Teeth were randomly divided into 7 groups (n=11), In experimental A group, adhesive was applied to dentin with agitation for 20 sec. In experimental N-A group, adhesive were continuously applied to dentin for 20 sec. Also control and experimental 1, 2, 3, 4 groups were dried for 10, 0, 5, 20, 30 seconds after applying adhesive, respectively, Adhesives were light cured for 10 sec. A gelatin capsule 5mm in diameter was filled with Aelitefil$^{TM}$ composite resin, placed on the treated dentin surface and light cured for 40 see, from three sides, All specimens were stored in distilled water at room temperature for 24 hours. The shear bond strengths were measured using a universal testing machine(AGS-1000 4D, Japan) at a crosshead speed of 5mm/min. An one-way ANOVA and LSD test were used for statistical analysis of the data. For SEM evaluation, seven specimens were made and sectioned. Representive postfracture and seven specimens were mounted on brass stubs, sputter-coated with gold and observed under SEM. The results were as follows : 1. The shear bond strength of experimental A group which adhesive were applied to dentin with agitation was higher than that of experimental N-A group (continuous application), and there was significant difference between two groups (p<0.01). 2. The interface between composite and dentin according to different application methods showed close adaptation in experimental A group and showed tinny gap in experimental N-A group. 3. The shear bond strength accoding to various air drying duration was the lowest value(7.57${\pm}$2.60 MPa) in experimental 1 group, so there was significant difference between experimental 1 group and other four groups (p<0.05). But there was no significant difference of shear bond strength between four groups (p>0.05). 4. The interface between composite and dentin according to various air drying duration showed close adaptation in control group and tinny gap in experimental 3 and 4 groups. But experimental 1 and 2 groups showed $30{\mu}$ and 6 - $10{\mu}m$ thick gaps, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.40 no.2
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• pp.145-150
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• 2007

This study was conducted to evaluate the application effects of phospho-gypsum fertilizer (PGF) as reclamation material in the newly reclaimed paddy fields located in Goheung and Youngam, Jeonnam province in Korea. The PGF used in this experiment was produced by Namhae Chemical Co. as the name of Soil-Saver$^{TM}$. Prior to rice transplanting, the PGF was applied as soil amendment as the amount of $3,000kg\;ha^{-1}$. The PGF increases rice plant height and number of tiller at the heading stage by 119.9 cm and 9.1, respectively, in Youngam area. The harvest index of brown rice increased up to 5 and 13% more in the PGF applied paddy field from both sites than in the non-application of PGF at paddy field before rice transplanting, and the ripening ratio in increased in both sites to 81 and 90%. Protein content of brown rice was also greater than in the non-application of PGF at the both sites. For the effects of the reclamation by PGF in the paddy field soils, we found that PGF reduced exchangeable Na to 18 and 28% for both sites, respectively, and increased exchangeable Ca and $SO_4$. And we found relatively higher amounts of $K_2O$, CaO and MgO in the rice plants from both sites applied with PGF.

• Journal of Life Science
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• v.28 no.12
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• pp.1424-1431
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• 2018

We prepared flocculated detritus-like organic marine snow originating from various organisms by fermentation using microorganisms; this fermented organic material was fed to the leptocephali of the eel (Anguilla japonica) to investigate whether or not such organic matter was an appropriate food source for the larvae. A strain was isolated from a biofloc technology system used to culture fish, and seven types of organic material from hen's egg, eel muscle, tuna muscle, lugworm, shrimp, manila clam, mussel, and sea squirt were fermented using isolated bacteria (Bacillus sp.). The fermented matter did not show any specific form and was larger than $10-20{\mu}m$ but no more than $100{\mu}m$ in size. Four diets (A-D) were prepared using the various fermented products, and the larvae were fed the prepared food from 20 days after hatching. The leptocephali fed the A, B, and C diets survived until 37, 39, and 37 days after hatching, respectively. However, the leptocephali fed the D diet survived for 60 days after hatching. The protein content of each diet was very similar, but the n-3 HUFA concentration in the D diet was approximately twice as high as that of the others.

• Journal of The Korean Association of Information Education
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• v.22 no.6
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• pp.613-628
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• 2018

The purpose of this study is to analyze the teaching and learning process of physical computing using coding block for elementary gifted students in science. In order to obtain implications for teaching physical computing, we set the learning objectives from the Computer and Information Literacy Evaluation Standards developed by the International Association for the Evaluation of Educational Achievement(IEA) and developed a teaching and learning program for physical computing through collaboration between science education and computer education experts according to learning objectives. The developed program was related to the use of the coding block MODI(TM) and 32 classes of physical computing instruction were conducted for 15 students of the 4th to 6th grade who belong to an education institute for the gifted in science affiliated to the University. In the physical computing class, the teaching and learning process was analyzed by collecting data such as classroom videos, class observation logs, teacher and student questionnaires, and interviews. Based on the results of the study, the implications of the teaching and learning process of physical computing using the coded blocks in the school education field were suggested. And we also explored the strategy of expanding the computational thinking through the activities of coding instruction to realize creative ideas.

• Korean Journal of Health Psychology
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• v.16 no.3
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• pp.537-555
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• 2011

The purpose of this study was two-fold. First, comparisons on the psychological and physical attributes of normal weight, overweight, and obese children were conducted. Second, the influence of BMI and physical fitness interaction on psychological adaptation in children with obesity was explored. Participants were 245 children between the ages of 9 and 13 years (64.5% males). Data on children considered overweight (n = 45) or obese (n = 78) were gathered from the Korean Obese Children's Physical Activity (KOCPA) projects. Normal weight children (n = 122) were recruited from two Seoul elementary schools. Psychological measurements included Weight Efficacy Life-style Questionnaire (WEL), Physical Self-efficacy Scale (PSES), Child Dietary Self-efficacy Scale (CDSS), Self-concept Inventory (SCI), and the Korean version of the Pediatric Quality of Life Intervention TM Version 4.0 Generic Core Scales (PedsQLTM4.0). BMI (kg/m2) and physical fitness (e.g., aerobic endurance, flexibility) were recorded by experts in exercise physiology. Results showed that children in the high BMI group reported poorer psychological adaption and demonstrated lower physical fitness when compared to the remaining groups. Compared to normal weight children, children considered overweight and obese were found to have lower physical self-efficacy, more negative self-concept, and poorer quality of life. Further, these children also had significantly lower physical fitness levels than their normal weight counterparts. Physical fitness was found to have a significant main effect on weight efficacy (WEL), physical self-efficacy (PSES), and quality of life (PedsQL) in children considered overweight or obese. A significant BMI-physical fitness interaction effect was found for self-concept (SCI) only. Children with higher BMI reported poorer self-concept regardless of fitness level whereas children with lower BMI and higher fitness reported more positive self-concept. Implications and limitations are discussed.

• Asia Marketing Journal
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• v.10 no.2
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• pp.31-69
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• 2008

The purpose of this study is to identify the organizational characteristics that enhance CRM performances of a company. Based on a review of diverse definitions of CRM performance, this study examines the relationships among CRM performance measures and organizational characteristics. A questionnaire survey of 123 CRM managers of Korean companies was conducted to test the proposed research model, and a series of structural equation modeling identified the strong effects of organizational characteristics on CRM performance. It was found that top management commitment to CRM and a firm's strategic readiness lead to high levels of CRM investment, which, in turn, enhance directly task-related performance and indirectly customer-related performance. This study also confirmed that customer orientation is significantly related to task-related CRM performance and that the variables of CRM commitment and organizational culture may enhance customerrelated performance indirectly through their effects on the task-related performance. However, organizational members' resistance to change was found to have no effects on CRM performance. Overall our research broadly supports the role of organizational characteristics revealed in the CRM literature.

• Nutrition Research and Practice
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• v.18 no.1
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• pp.19-32
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• 2024

BACKGROUND/OBJECTIVES: Atherosclerosis is associated with increased inflammation in the visceral adipose tissue (VAT). Vitamin D has been reported to modulate the inflammatory responses of stromal vascular cells (SVCs) and adipocytes in adipose tissue, but the role of vitamin D in atherosclerosis biology is unclear. This study examined the effects of in vitro 1,25-dihydroxyvitamin D₃ (1,25[OH]₂D₃) treatment on the inflammatory responses of SVCs and adipocytes from atherosclerotic mice. MATERIALS/METHODS: C57BL/6J (B6) mice were divided randomly into 2 groups and fed a 10% kcal fat control diet (control group, CON) or 41% kcal fat, 0.21% cholesterol (high fat + cholesterol, HFC) diet (obese group, OB), and B6.129S7-Ldlr^tm1Her/J (Ldlr^-/-) mice were fed a HFC diet (obese with atherosclerosis group, OBA) for 16 weeks. SVCs and adipocytes isolated from VAT were pre-incubated with 1,25(OH)₂D₃ for 24 h and stimulated with lipopolysaccarides for the next 24 h. Proinflammatory cytokine production by adipocytes and SVCs, the immune cell population in SVCs, and the expression of the genes involved in the inflammatory signaling pathway in SVCs were determined. RESULTS: The numbers of total macrophages and SVCs per mouse were higher in OB and OBA groups than the CON group. The in vitro 1,25(OH)₂D₃ treatment significantly reduced macrophages/SVCs (%) in the OBA group. Consistent with this change, the production of interleukin-6 and monocyte chemoattractant protein 1 (MCP-1) by SVCs from the OBA group was decreased by 1,25(OH)₂D₃ treatment. The 1,25(OH)₂D₃ treatment significantly reduced the toll-like receptor 4 and dual-specificity protein phosphatase 1 (also known as mitogen-activated protein kinase phosphatase 1) mRNA levels in SVCs and MCP-1 production by adipocytes from all 3 groups. CONCLUSIONS: These findings suggest that vitamin D can attribute to the inhibition of the inflammatory response in VAT from atherosclerotic mice by reducing proinflammatory cytokine production.

• Parasites, Hosts and Diseases
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• v.34 no.1
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• pp.59-68
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• 1996

This study investigated the enzyme histochemical localization and characteristics of lactate (LDH) and malate dehydrogenase (MDH) related with the oxidation-reduction metabolism in the sparganum and adult of 5. erinacei. By enzyme histochemical assay, activity of LDH was strong in the tegument and subtegumental muscle layers of the adult and sparganum. Activity of MDH was strong in the tegument of the sparganum and subtegumental muscle layers of the adult. However it was weak in the tegument of the adult. By electrophoresis, 45 kDa band was major and common in LDH of adults and spargana. The 150 kDa molecule was the major and common band in MDH of adults and r -spargana (from experimentally infected rats) . By isoelectrofocusing, isoelectric points (Pl) or 4 MDH isogyme from adult worm were 6.0.6.5, 6.7 and 7.1, respectively. Pl 6.0 was the major band. The active range of pH for MDH was about pH 6-8 and the optimum pH was pH 7 The effective temperature on the MDH was about $30^{\circ}C$∼$50^{\circ}C$ and the optimum temperature was about 40℃ in spargana md adult worm. In the stability against heat, when MDH was heated at 85℃ for 10 seconds, the activity was denatured perfectly. Maximum activity or MDH was 19.4 unit in the s-sparganum (from snakes), 24.5 unit in the r-sparganum (from rats) and 108.0 unit in the adult worm. The maximum activity was higher in adults than in spargana. The present result showed us that the nutrients absorbed through the tegument were transferred into inner tissues and were utilized as the source of metabolism. According to the habitat of the parasite, the isozymes of LDH and MDH are activated differently, and by this different activation the sparganum and adult can adapt themselves to parasitic circumstances.