• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1129-1134
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• 2007

In the previous our study, a cDNA that encodes protein disulfide isomerase from Bombyx mori (bPDI)was isolated and characterized. bPDI has an open reading frame of 494 amino acids contained two PDI-typical thioredoxin active site of WCGHCK and ER (endoplasmic reticulum) retention signal of the KDEL motif at its C-terminal. Recent studies have demonstrated that misfolded proteins are accumulated in many diseases including Alzheimer’s, goiter, emphysema, and prion infections. bPDI was over-expressed or knock-downed in Sf9 cells to study the relationship between bPDI expression and protections against protein misfolding. bPDI gene was cloned in insect expression vector pIZT/V5-His for over-expression and bPDI double-stranded RNA (dsRNA) was generated for knock-down. Over-expression of bPDI significantly improved survival rate, but bPDI dsRNA transfection significantly reduced survival rate after 48 hours exposure. In mock-transfected or wild-type cells had no significant effect. The results support the view that bPDI is one of the important intracellular components for cell protect mechanism, especially, against ER stress such as protein misfolding.

• Journal of Life Science
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• v.21 no.8
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• pp.1190-1198
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• 2011

Extraction methods of medicinal plants were evaluated for growth enhancing effects of human neuroblastoma SK-N-SH cells. Hot-water extraction (reflux for 5 hr), hot-water extraction post treatment (100$^{\circ}C$ or 120$^{\circ}C$, 90 min) and ethanol extraction (reflux for 5 hr) methods were applied to Angelica gigas, Rhemania glutinosa, Paeonia lactiflora and Cnidium officinale samples to extract their constituents. Cells were treated for 2 hr with various concentrations of extracts (0, 0.5, 1, 2, 4 ${\mu}g/{\mu}l}$ media) prior to $H_2O_2$ (250 ${\mu}M$) treatment for 2 hr to provide oxidative stress. Cell viability, caspase-3 expression and apoptosis were measured for cells treated with sample extracts. Hot-water extract exhibited a stronger growth enhancing and apoptosis protecting ability than other extracts. These activities were shown at less than 1 ${\mu}g/{\mu}l}$ concentration, and not greater than 2 ${\mu}g/{\mu}l}$ concentration. Hot-water extract contained more polyphenolic compounds than other extracts coming along with stronger antioxidant activity. The efficacy of antioxidant activity was stronger in the hot-water extract of Angelica gigas than other hot-water extracts of medicinal plants. These results suggest that hot-water extraction is an appropriate method to extract materials for growth enhancing and apoptosis protection of SK-N-SH cells, and hot-water extracts of Angelica gigas might be useful materials for protection from aging brain cells.

• Journal of fish pathology
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• v.27 no.1
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• pp.57-65
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• 2014

Copper ($CuSO_4$) has been widely used to control algae and pathogens in fish culture ponds. However, its toxic effects on fish depend not only on its concentration in water but also on water quality. The susceptibility of the rockfish, Sebastes schlegeli to copper was evaluated at three water-temperatures (WT; 18, 23 and $28^{\circ}C$) for 4 days. After the exposure of two copper concentrations (100 and $200{\mu}g/L$), a hematological effect was exerted on rockfish, by causing changes in red blood cell count and hematocrit value at $28^{\circ}C$. Total protein levels of the fish showed a tendency of co-increase with glucose depend on the WT, after copper exposure. However, the plasma calcium and magnesium levels were significantly increased at $200{\mu}g/L$ copper, regardless of the WT. Enzymes activities including ALT and LDH in serum were also significantly increased depend upon the copper treatment only. This indicates that inorganic components and enzymes activities were sensitive indexes to stress by toxicant such as copper. The cortisol levels were significantly elevated by both WT rising and copper treatment in serum of rock fish. In conclusion, these changes can be seen as an initial response to temperature stress and as a sustaining response to copper exposure. The present findings suggest that a simultaneous stress by temperature change and copper exposure could accelerate an alteration of hematological and plasma biological parameters in the rockfish.

• The Korean Journal of Food And Nutrition
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• v.20 no.4
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• pp.476-486
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• 2007

This study was performed to investigate the dietary behaviors, perceived stress, and health-related factors along with their correlations in University students. The number of subjects was 150(64 males and 86 females), and the results of the study were as follows: Stress was felt by over 80% of the male and female students. The male students were more stressed than the females for economic value, gender difference, professor and drinking-related stress factors, and there was a significant difference between the genders. The female students had more clinical symptoms from stress than the male students in terms of dizziness, indigestion and constipation(p<0.01, p<0.001). The amount of food intake under stress was significantly different by gender. The female students preferred sweet tasting items, whereas the male students preferred hot tasting item when under stress. Also the intake of candy and chocolate when under stress in the male and female students was $2.00{\pm}0.74$ and $2.41{\pm}0.75$, respectively. The female students consumed candy and chocolate more than the male(p<0.01). Furthermore, 62.5% of the male students and 30.2% of the female students exercised to get rid of stress: the use of ball games as exercise in male and female students was $1.59{\pm}0.83$, $1.01{\pm}0.11$, respectively. Many students drank alcohol and smoked while under stress. In particular, the male students smoked more than normal as compared to the females, and there was a significant gender difference(p<0.001). The clinical symptoms positively correlated with the life stress level were degree of nervousness, sweaty, achy neck and shoulders, sore back, dizziness, eye fatigue, headache and indigestion. The amount of food intake under stress was positively correlated to the clinical symptom of headache. These results indicate the effects of life stress on dietary behaviors, food choice, and health status. Stress not only changed dietary behaviors, but was also related to health status. Therefore, education with regard to nutrition is necessary if college students are to practice food eating habits to correctly manage life stresses.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.163-176
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• 2009

Investigating endophyte distribution, naturally occurring in native grasses, is important for understanding endophyte-grass associations and using the beneficial effects of endophytes in cultivated plants. The goal of this study was to investigate endophytes from natural Festuca spp. in Yunnan, Guizhou, and Sichuan Provinces of China, and to study the compatibility between the endophytes and turf type tall fescue (Festuca arundinacea) which is widely used for lawn and athletic fields in that region. Of 628 accessions in F. ovina, 421 had endophytes identified in leaf sheath from on-site microscopic examination. From Festuca spp, three isolates were obtained from the seeds and ninety isolates were obtained from seedlings established from the collected seeds. The isolates from F. ovina and F. stapfii were tentatively identified as Neotyphodium typhinum and Neotyphodiumstarii, respectively. We tested compatibility of the two fungal species with seven tall fescue cultivars, Little Hero, Sub Boy, Eldorado, Arid III, Millennium, Crossfire, and Fawn. N. typhinum or N. starii did not infect 'Fawn' with either seed injection or seed soaking method. The highest infection rate byboth N. typhinum and N. starii was in 'Sun Boy' and 'Eldorado'. There were significant interaction effects between tall fescue cultivar and type of endophyte on infection.

• Journal of the Microelectronics and Packaging Society
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• v.25 no.3
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• pp.61-66
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• 2018

This research scrutinizes the self-annealing characteristics of copper used to metal interconnection for application of DRAM fabrication process. As the time goes after the copper deposited, the grain of copper is growing. It is called self-annealing. We use the electroplating method for copper deposition and estimate two kinds of electroplating chemicals having different organic additives. As the time of self-annealing is elapsed, sheet resistance decreases with logarithmic dependence of time and is finally saturated. The improvement of sheet resistance is approximately 20%. The saturation time of experimental sample is shorter than that of reference sample. We can find that self-annealing is highly efficient in grain growth of copper through the measurement of TEM analysis. The structure of copper grain is similar to the bamboo type useful for current flow. The results of thermal excursion characteristics show that the reliability of self-annealed sample is better than that of sample annealed at higher temperature. The self-annealed sample is not contained in hillock. The self-annealed samples grow until $2{\mu}m$ and develop in [100] direction more favorable for reliability.

• Korean Journal of Ichthyology
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• v.18 no.2
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• pp.65-77
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• 2006

Gene transcripts potentially responsive to the heat stress were surveyed by cDNA microarray analysis in mud loach (Misgurnus mizolepis). Transcriptional profiles of hepatic tissue in the fish exposed to either $23^{\circ}C$ or $32^{\circ}C$ for 4 weeks were compared each other by 3 replicated hybridization assays using 1,124 unigene clones selected from mud loach liver expressed sequence tags (ESTs). A total of 93 clones showed the substantially increased mRNA levels (>2-fold) in $32^{\circ}C$-exposed group when compared in $23^{\circ}C$control group. It includes various enzymes and proteins involved in energy pathway, protease/protein metabolisms, immune/antioxidant functions, cytoskeleton/cell structure, transport and/or signal transduction. Maximum level of increase was up to 15-fold relative to $23^{\circ}C$ treatment. Heat exposure also resulted in the significant decrease (less than 50% relative to $23^{\circ}C$-exposed fish) of the transcriptional activities in 85 genes. Besides the above categories, yolk protein (vitellogenin) and ribosomal proteins were notably down regulated in the fish exposed to heat stress. A number of novel gene transcripts were also detected in both up-regulated and down-regulated groups.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.7
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• pp.8-16
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• 2010

In this paper, we investigated the effects of $O_2$ fraction on the properties of Al-doped ZnO (AZO) thin films prepared by radio frequency (RF) magnetron sputtering. Hall, photoluminescence (PL), and X-ray photoelectron spectroscopy (XPS) measurements revealed that the p-type conductivity was exhibited for AZO films with an $O_2$ fraction of 0.9 while the n-type conductivity was observed for films with $O_2$ fractions in range of 0 - 0.6. PL and XPS also showed that the acceptor-like defects, such as zinc vacancies and oxygen interstitials, increased in films prepared by an $O_2$ fraction of 0.9, resulting in the p-type conductivity in the films. Hall results indicated that AZO films prepared by $O_2$ fractions in range of 0 - 0.6 can be used for electrode layers in the applications of transparent thin film transistor. We concluded from the X-ray diffraction analysis that worse crystallinity with a smaller grain size as well as higher tensile stress was observed in the films prepared by a higher $O_2$ fraction, which is related to incorporation of more oxygen atoms into the films during deposition. The study of atomic force microscope suggested that the smoother surface morphology was observed in films prepared by using $O_2$ fraction, which causes the higher resistivity in those films, as evidenced by Hall measurements.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.1
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• pp.95-104
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• 2002

A methods to calculate non-linear moment-curvature relations of high-strength PSC flexural members for numerical analysis has been proposed. The moment-curvature relations were calculated with assumptions of design codes and by the layer method. The results of the proposed procedures for moment-curvature relations and numerical analysis were compared with those of pre-existing tests. The absorption energy rate of the design codes was about 30% larger than that of the layer method. The ultimate load and the external work of the layer method were 90% and 85% of those of tests, respectively The ultimate load of the strength design method was 97% of that of tests, but the external work was over-estimated with 122%. The ultimate load and external work by the proposed equation of the CEB-FIP Model Code were 113% and 173% of those of tests, respectively. It show that the use of ultimate strain of 0.0035 should be over-estimated for high-strength concrete. The procedure of non-linear numerical analysis of this research could be stably simulated the behavior of concrete flexural members until the ultimate state, and calculate results of the load-deflection relation and cracking pattern were very similar with those of tests.

• Journal of dental hygiene science
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• v.7 no.2
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• pp.89-96
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• 2007

The purpose of this study was to examine the relationship between the self-expression level of dental hygiene students related to communicative competence and their stress during clinical practice and what affected their stress. The subjects in this study were 125 dental hygiene students in W college, on whom a survey was conducted from September 18 through 30, 2006. After the collected data were analyzed with SPSS WIN 10.0 program, the following findings were acquired: 1. When a factor analysis was made to evaluate the self-expression of the students, there appeared three different categories of self-expression: voice/content, facial expression/attitude and sentiment. The three made a 58.1% prediction of their self-expression. As for overall reliability, they turned out highly reliable(Cronbach'a = .881). 2. The dental hygiene students got a mean of 3.58 out of possible five points in self-expression, which indicated that they expressed themselves relatively well. Concerning connections between their general characteristics and self-expression level, those who were inactive during clinical practice got a mean of 3.28, whereas the others who were active got a mean of 3.85. It implied that those who took a more active attitude to clinical practice expressed themselves better(p < .01). The person with whom they found it hard to get along made a statistically significant difference to their self-expression(p < .05). The students who didn't fare well with dental hygienists got the best score(3.70). The second best group(3.53) didn't get along with dentists, followed by assistant nurses(3.46) and patients/caregivers(3.31). As for the impact of the field of dream job, the students who hoped to work or study overseas(4.21) excelled in self-expression those who wanted to be hired in a general hospital, to go onto a school of higher grade and to work in a public dental clinic(p < .05). Among the general characteristics, satisfaction level with major, health status and motivation of choosing dental hygiene made no statistically significant differences to their self-expression. 3. Regarding relations between self-expression level and stress about clinical practice, those who didn't express themselves properly in terms of sentiment scored higher in stress level(3.65). Their stress was statistically significantly different according to self-expression level (p < .05). 4. As for the influence of self-expression and general characteristics on stress with clinical practice, sentiment was selected from among the self-expression categories as a decisive factor to affect stress. Their stress varied statistically significantly with that(p < .05). In contrast, their demographic variables made no statistically significant difference to that, which made a 79.2% prediction of it.