• The Journal of Advanced Prosthodontics
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• v.8 no.2
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• pp.94-100
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• 2016

PURPOSE. To evaluate the effects of hydrogen peroxide pretreatment and heat activation of silane on the shear bond strength of fiber-reinforced composite posts to resin cement. MATERIALS AND METHODS. The specimens were prepared to evaluate the bond strength of epoxy resin-based fiber posts (D.T. Light-Post) to dual-curing resin cement (RelyX U200). The specimens were divided into four groups (n=18) according to different surface treatments: group 1, no treatment; group 2, silanization; group 3, silanization after hydrogen peroxide etching; group 4, silanization with warm drying at $80^{\circ}C$ after hydrogen peroxide etching. After storage of the specimens in distilled water at $37^{\circ}C$ for 24 hours, the shear bond strength (in MPa) between the fiber post and resin cement was measured using a universal testing machine. The fractured surface of the fiber post was examined using scanning electron microscopy. Data were analyzed using one-way ANOVA and post-hoc analysis with Tukey's HSD test (${\alpha}=0.05$). RESULTS. Silanization of the fiber post (Group 2) significantly increased the bond strength in comparison with the non treated control (Group 1) (P<.05). Heat drying after silanization also significantly increased the bond strength (Group 3 and 4) (P<.05). However, no effect was determined for hydrogen peroxide etching before applying silane agent (Group 2 and 3) (P>.05). CONCLUSION. Fiber post silanization and subsequent heat treatment ($80^{\circ}C$) with warm air blower can be beneficial in clinical post cementation. However, hydrogen peroxide etching prior to silanization was not effective in this study.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.5
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• pp.37-48
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• 2015

Soil nutrient management is important to maintain the constant productivity of seedling production in the nursery for successful forest restoration. This study investigated the effects of organic manure and chemical fertilizer application levels on the growth, soil properties, and nutrient concentrations of yellow poplar seedlings. One-year-old yellow poplar seedlings were treated with the combination of 3 level organic manures(0, 5 Mg/ha, 10 Mg/ha; mixture of poultry manure, cattle manure, swine manure, and sawdust) and 3 level nitrogen-phosphorus-potassium(NPK) chemical fertilizers(0, 1x(urea, $30g/m^2$; fused superphosphate, $70g/m^2$; potassium chloride, $15g/m^2$), 2x). Organic manure significantly increased the soil pH and the concentrations of nitrogen, available phosphorous, exchangeable potassium, calcium, and magnesium. In contrast, the NPK chemical fertilizer decreased the soil pH and exchangeable calcium concentration, did not affect the soil concentrations of nitrogen and magnesium, and increased the concentrations of available phosphorous and exchangeable potassium. Both organic manure and NPK chemical fertilizer treatments increased the seedling height, root collar diameter, and dry weight by 39% and 25%, respectively. The treatment with manure 5 Mg/ha and NPK 2x chemical fertilizer mostly increased seedling dry weight by 2.6 times more than that of the control. Compared to the effects of the fertilization treatments on the soil properties, the effects on nutrient concentrations in the leaves were relatively small. These findings indicate that organic manure that was derived from livestock byproducts and sawdust can be utilized with chemical fertilizer to improve seedling production as well as conserving soil quality.

• Toxicological Research
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• v.32 no.2
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• pp.159-173
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• 2016

Crickets have been attracting considerable interest in the field of nutrition and toxicology due to the global exhaustion of food resulting from a growing population. The cricket is normally eaten in several countries after roasting, similar to the grasshopper; however, safety evaluation data on cricket powder is limited. Here, we performed general toxicity studies of cricket powder including a single, 2-week repeated dose range evaluation test, a 13-week repeated oral dose toxicity test in Sprague-Dawley rats, a single oral dose toxicity test in Beagle dogs, and a skin sensitization test in guinea pigs following the Organization for Economic Cooperation and Development test guidelines 406 and 408 in addition to Good Laboratory Practice. To investigate the NOAEL and target organs of cricket powder, Sprague-Dawley rats were allocated to 4 groups: vehicle control, 1,250 mg/kg, 2,500 mg/kg, 5,000 mg/kg dose test groups and cricket powder was administered over 13 weeks after single dose and dose range finding studies in rats based on the results of the single oral administration toxicity study in rats and Beagle dogs. The results of the study showed that the NOAEL of cricket powder was over 5,000 mg/kg for both sexes of rats without adverse effects in a 13-week repeated oral toxicity study and there was no skin hypersensitivity reaction. Therefore, our results reveal that crickets can be widely used as a new substitute food or nutrient resource.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.1
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• pp.30-35
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• 2016

Rice cultivation in paddy field affects the global balance of methane ($CH_4$) as a key greenhouse gas. To evaluate a potential use of by-product gypsum fertilizer (BGF) in reducing $CH_4$ emission from paddy soil, $CH_4$ fluxes from a paddy soil applied with BGF different levels (0, 2, 4 and $8Mg\;ha^{-1}$) were investigated by closed-chamber method during rice cultivation period. $CH_4$ flux significantly decreased (p<0.05) with increasing level of BGF application. $8Mg\;ha^{-1}$ of BGF addition in soil reduced $CH_4$ flux by 60.6% compared to control. Decreased soil redox potential (Eh) resulted in increasing $CH_4$ emission through a $CO_2$ reduction reaction. The concentrations of dissolved calcium (Ca) and sulfate ion (${SO_4}^{2-}$) in soil pore water were significantly increased as the application rate of BGF increased and showed negatively correlations with $CH_4$ flux. Decreased $CH_4$ flux with BGF application implied that ${SO_4}^{2-}$ ion led to decreases in electron availability for methanogen and precipitation reaction of Ca ion with inorganic carbon including carbonate and bicarbonate as a source of $CH_4$ formation under anoxic condition. BGF application also increased rice grain yield by 16% at $8Mg\;ha^{-1}$ of BGF addition. Therefore, our results suggest that BGF application can be a good soil management practice to reduce $CH_4$ emission from paddy soil and to increase rice yield.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.540-545
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• 2010

This study was conducted to investigate effects of irrigation points on cucumber growth and water saving under greenhouse. Automatic irrigation system and tensiometers were installed at four plots to measure soil water tension and properties of irrigated water. Each plot was irrigated at different irrigation points; soil water tension of 15, 20, 30, and 40 kPa, respectively. Conventional irrigation plot without tensiometer was also investigated. The total yield and sugar contents of cucumber had no significant differences between plots. However, irrigated water volumes were saved most when irrigation points were 30, and 40 kPa. The two plots of 30, and 40 kPa treatments used about 60% less of irrigated water than the plot of conventional practice did. In conclusion, this research suggested that the optimum irrigation point for cucumber cultivation in greenhouse can be soil water tension of 30 kPa based on the results of overall cucumber quality, and Greenhouse water usage.

• The Korean Journal of Community Living Science
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• v.18 no.1
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• pp.161-175
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• 2007

It is important for young adults to establish good dietary behavior for healthy life. The prevalence of obesity in college students has increased gradually. The obesity is one of the most prevalent health problems in S. Korea. Moreover, obesity is closely related with the disease such as cardiovascular disease, diabetes mellitus. The purpose of this study was to evaluate health practice, serum components and nutrient intake of the college students according to Body Mass Index (BMI) level. 400 male and female freshmen students in 4 year university located near to Seoul metropolitan area were surveyed respectively through the health check-up procedure for college entrance in February. Survey was carried out for them by questionnaires, including a 24-hour dietary recall and anthropometric measurements. Blood samples were obtained while fasting. Nutrient intake was expressed by DDS(Dietary Diversity Score by 5 food groups) and DVS(Dietary Variety Score). Nutrition level was analyzed by Can-Pro (Korea Nutrition Association). And for the quantity intake, percentage ratio against daily requirement(by KDRIs) and MAR(Mean Adequacy Ratio) were calculated. Underweight group($BMI<18.5kg/m^2$), normal weight group($18.5) and overweight group($BMI<23.0 kg/m^2$) were 18.5%, 61.2% and 19.3% respectively. Nutrient intake levels and food intake status were not significantly different among three groups. The mean nutrient adequacy ratio (MAR) was not significantly different by BMI status. Nutrient intakes of calcium, iron, and riboflavin were especially low for all the students. Overweight group showed high blood pressure(120.9/79.3 mmHg) compared with the underweight group (116.4/ 75.8mmHg) but the difference was not significant. The serum triglyceride level in overweight group (94,0mg%) was higher than that in normal (70.9mg%) or underweight group(70.8mg%)(p<0.05). HDL-cholesterol level in overweight (43.8 mg%) group was not significantly different from that in underweight group (45.9mg%). BMI was positively correlated with blood pressure, hemoglobin, and the intake of total fat and cholesterol. But it was negatively correlated with HDL-cholesterol level. With these results overweight group is closely related with the cardiovascular disease risks, such as high blood pressure and high triglycerides and cholesterol. Thus, a health intervention program including weight control is required for young adults.

• Women's Health Nursing
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• v.2 no.1
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• pp.138-157
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• 1996

Recently, there has been increase perception of health promotion with development of the economic state and science. Individual's responsibility and psychosocial factors have impacted on the individual's lifestyle. Health promotion can be maintained or improved through changes of lifestyle of individuals. Also, there has been supported results of health behavior health has been focused on menopausal symptom and reproductive organ. Until recently, little research has been available on the health or health care of midlife women. The purpose of this study was to explain relationship between health promoting lifestyle and hardiness, gender role characteristics. A total of 254 items of data were obtained from randomly selected subjects. The data collected from the interviews were analyzed using SPSS, yielding frequency, mean. t-test, ANOVA, Pearson Correlation, Stepwise multiple regression. The result of this study are as follows : 1) For the health promoting lifestyle, the mean score was 116.3, the highest score was nutrition(3.30) and interpersonal support(2.86), the lowest score was exercise(1.68). The highest subscale for the hardiness was committment(2.44). Also for the gender role characteristics was higher than median score(37.8). 2) There was a statistically difference the demographic variables. A total health promotion lifestyle was predicted by income and marriage satisfaction, hardiness was predicted by education, income, marriage satisfaction, support person and gender role characteristics was predicted by education. 3) With regard to the relationship among health promoting lifestyle, hardiness, gender role characteristics, the correlation coefficient between health promoting lifestyle and hardiness was r=-.48, p<.001. Also there were significant correlation between health promoting lifestyle and gender role characteristics(r=.22, p<.01), hardiness and gender role characteristics(r=-.39, p<.001). 4) A stepwise multiple regression analysis was done on the total health promoting lifestyle score using the demographic variables, hardiness subscale and gender role characteristics for independent variables. A total of 25% of the variance was explained inthe total health promoting lifestyle by the control, challenge and marriage satisfaction. In conclusion, hardiness and gender role characteristics were engaged in health promoting activity in midlife women. This study also provides new information about the health practices that midlife women report they practice. Therefore, nursing intervention to increase women's health have to be planed program that consider on the basis the results of this study.

• 한국HCI학회:학술대회논문집
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• 2009.02a
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• pp.961-970
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• 2009

Over the last decade, interactive devices such as mobile phones have become complicated drastically mainly because of feature creep, the tendency for the number of features in a product to rise with each release of the product. One of the ways to reduce the complexity of a multi-functional device is to design it consistently. Although the definition of consistency is elusive and it is sometimes beneficial to be inconsistent, in general, consistently designed systems are easier to learn, easier to remember, and causing less errors. In practice, however, it is often not easy to design the user interaction or interface of a multi-functional device consistently. Since the interaction design of a multi-functional device should deal with a large number of design variables and relations among them, solving this problem might be very time-consuming and error-prone. Therefore, there is a strong need for a well-developed methodology that supports the complex design process. This study has developed an effective and efficient methodology, called CUID (Consistent Design of User Interaction), which focuses on logical consistency rather than physical or visual consistency. CUID deals with three main problems in interaction design: procedure design for each task, decisions of available operations(or functions) for each system state, and the mapping of available operations(functions) and interface controls. It includes a process for interaction design and a software tool for supporting the process. This paper also demonstrates how CUID supports the consistent design of user interaction by presenting a case study. It shows that the logical inconsistencies of a multi-functional device can be resolved by using the CUID methodology.

• Nutrition Research and Practice
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• v.9 no.1
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• pp.22-29
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• 2015

BACKGROUND/OBJECTIVES: Recently, anthocyanins have been reported to have various biological activities. Furthermore, anthocyanin-rich purple corn extract (PCE) ameliorated insulin resistance and reduced diabetes-associated mesanginal fibrosis and inflammation, suggesting that it may have benefits for the prevention of diabetes and diabetes complications. In this study, we determined the anthocyanins and non-anthocyanin component of PCE by HPLC-ESI-MS and investigated its anti-diabetic activity and mechanisms using C57BL/KsJ db/db mice. MATERIALS/METHODS: The db/db mice were divided into four groups: diabetic control group (DC), 10 or 50 mg/kg PCE (PCE 10 or PCE 50), or 10 mg/kg pinitol (pinitol 10) and treated with drugs once per day for 8 weeks. During the experiment, body weight and blood glucose levels were measured every week. At the end of treatment, we measured several diabetic parameters. RESULTS: Compared to the DC group, Fasting blood glucose levels were 68% lower in PCE 50 group and 51% lower in the pinitol 10 group. Furthermore, the PCE 50 group showed 2-fold increased C-peptide and adiponectin levels and 20% decreased HbA1c levels, than in the DC group. In pancreatic islets morphology, the PCE- or pinitol-treated mice showed significant prevention of pancreatic ${\beta}$-cell damage and higher insulin content. Microarray analyses results indicating that gene and protein expressions associated with glycolysis and fatty acid metabolism in liver and fat tissues. In addition, purple corn extract increased the phosphorylation of AMP-activated protein kinase (AMPK) and decreased phosphoenolpyruvate carboxykinase (PEPCK), glucose 6-phosphatase (G6pase) genes in liver, and also increased glucose transporter 4 (GLUT4) expressions in skeletal muscle. CONCLUSIONS: Our results suggested that PCE exerted anti-diabetic effects through protection of pancreatic ${\beta}$-cells, increase of insulin secretion and AMPK activation in the liver of C57BL/KsJ db/db mice.

• Nutrition Research and Practice
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• v.9 no.1
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• pp.79-86
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• 2015

BACKGROUND/OBJECTIVES: It is well-known that alcohol consumption is associated with stroke risk as well as with aldehyde dehydrogenase 2 gene (ALDH2) polymorphisms. However, it is unclear whether ALDH2 polymorphisms are associated with stroke risk independent of alcohol consumption and whether such association is modified by sex. We evaluated sex-specific associations of a common ALDH2 polymorphism and alcohol consumption with stroke risk in a Korean population. SUBJECTS/METHODS: We conducted a prospective cohort study involving 8,465 men and women, aged 40-69 years and free of stroke between June, 2001 and January, 2003, and followed for the development of stroke. We identified new cases of stroke, which were self-reported or ascertained from vital registration data. Based on genome-wide association data, we selected a single-nucleotide polymorphism (rs2074356), which shows high linkage disequilibrium with the functional polymorphism of ALDH2. We conducted Cox proportional hazards regression analysis considering potential risk factors collected from a baseline questionnaire. RESULTS: Over the median follow-up of 8 years, 121 cases of stroke were identified. Carrying the wild-type allele of the ALDH2 polymorphism increased stroke risk among men. The multivariate hazard ratio [95% confidence interval] of stroke was 2.02 [1.03-3.99] for the wild-type allele compared with the mutant alleles, but the association was attenuated after controlling for alcohol consumption. Combinations of the wild-type allele and other risk factors of stroke, such as old age, diabetes mellitus, and habitual snoring, synergistically increased the risk among men. Among women, however, the ALDH2 polymorphism was not associated with stroke risk. CONCLUSIONS: The prospective cohort study showed a significant association between a common ALDH2 polymorphism and stroke risk in Korean men, but not in Korean women, and also demonstrated that men with genetic disadvantages gain more risk when having risk factors of stroke. Thus, these men may need to make more concerted efforts to control modifiable risk factors of stroke.