• Investigative Magnetic Resonance Imaging
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• v.4 no.1
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• pp.27-33
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• 2000

Purpose: To determine the electronic spin relaxation times, $T_{le}$, of three commercially available Gd-chelated MR contrast agents, Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA, using Electron Paramagnetic Resonance(EPR) technique. Material and Methods: The paramagnetic MR contrast agents, Gd-DTFA(Magnevist) , Gd-DTFA-BMA(OMNISCAN) and Gd-DOTA(Dotarem), were used for this study, The EPR spectra of these contrast agents, which were prepared 2:1 methanol/water solution, were obtained at low temperatures, from $-160^{\circ}C~20^{\circ}C$. The glassy-state EPR spectra for these contrast agents were then fitted by the simulation spectra generated with different zero-field splitting (ZFS) parameters by a computer simulation program 'GEN', which generates the EPR powder spectrum using a given ZFS in $3{\times}3$ tensor. Finally, the spin relaxation times of the contrast agents were then determined from the $T_{2e}$, D, and E values of the best simulation spectra using the McLachlan's theory of average relaxation rate. Results: The electronic transverse spin relaxation times, $T_{2e}'s$, of Gd-DTPA, Gd-DTPA-BMA and Gd-DOTA were 0.113ns, 0.147ns and 1.81ns respectively. The g-values were 1.9737, 1.9735 and 1.9830 and the electronic spin relaxation times, $T_{1e}'s$, were 18.70ns, 33.40ns and $1.66{\mu}s$, respectively. Conclusion: The results of these studies reconfirm that the paramagnetic MR contrast agents with larger ZFS parameters should have shorter $T_{1e}'s$. Among three contrast agents used for this study, Gd-DOTA chelated with cyclic ligand structure shows better electronic property then the others with linear structure. Thus, it is concluded that the exact determination of ZFS parameters is the important factor in evaluating relaxation enhancement effect of the agents and in developing new contrast agents.

• The Korean Journal of Malacology
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• v.24 no.2
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• pp.121-130
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• 2008

In other aquaculture species, large improvements in growth have been achieved through selective breeding. Ezo abalone(Haliotis discus hannai) and disk abalone(H. discus discus) are major aquatic animals cultured in Asia, but selective breeding for the promotion of growth with these abalones has not been actively pursued. Recently significant efforts are being made to promote production of these species through selective breeding in Korea. The aims of this work were to estimate the general genetic parameters, heritabilities, and genetic and phenotypic correlations on growth-related traits at 1-year old in two Korean abalone subspecies, H. discus hannai and H. discus discus, by using multiple trait animal model. The data were collected from the records of 1,504 individuals produced from 22 sires and 26 dams in H. discus hannai and 297 individuals produced from 5 sires and 6 dams in H. discus discus, which evaluated by the Genetics and Breeding Research Center, National Fisheries Research & Development Institute(NFRDI). Genetic parameters were estimated for these abalone subspecies raised in Bukjeju branch, NFRDI, from May 20, 2004 to May 16, 2005, respectively. The heritability estimates obtained from restricted maximum likelihood(REML) were higher than expected, ranging from 0.40 to 0.43 for growth traits shell length, shell width and body weight in H. discus hannai and from 0.26 to 0.51 in H. discus discus, respectively. The heritabilities for shell shape and condition factor were lower than others of growth traits such as ranging from 0.09 to 0.19 in H. discus hannai and from 0.10 to 0.23 in H. discus discus, respectively. Genetic and phenotypic were > 0.93 between shell parameters and weight in two abalone species, respectively, indicating that breeding for weight gains could be successfully achieved by selecting for shell length.

• Science of Emotion and Sensibility
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• v.16 no.1
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• pp.29-42
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• 2013

In this paper, we analyze the effect of the depth perception, volume perception and visual discomfort according to the change of the quality of the depth image and the depth of the major object. For the analysis, a 2D image was converted to eighteen 3D images using depth images generated based on the different depth position of a major object and background, which were represented in three detail levels. The subjective test was carried out using eighteen 3D images so that the degrees of the depth perception, volume perception and visual discomfort recognized by the subjects were investigated according to the change in the depth position of the major object and the quality of depth map. The absolute depth position of a major object and the relative depth difference between background and the major object were adjusted in three levels, respectively. The details of the depth map was also represented in three levels. Experimental results showed that the quality of the depth image differently affected the depth perception, volume perception and visual discomfort according to the absolute and relative depth position of the major object. In the case of the cardboard depth image, it severely damaged the volume perception regardless of the depth position of the major object. Especially, the depth perception was also more severely deteriorated by the cardboard depth image as the major object was located inside the screen than outside the screen. Furthermore, the subjects did not felt the difference of the depth perception, volume perception and visual comport from the 3D images generated by the detail depth map and by the rough depth map. As a result, it was analyzed that the excessively detail depth map was not necessary for enhancement of the stereoscopic perception in the 2D-to-3D conversion.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.2
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• pp.29-48
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• 2000

This study was designed to diagnose the correlations between health promotion behavior and primary school students' demographic characteristics and their self-concept, and also this study was aimed at representing the basic data of proper instruction method and school health program with the respective to primary school students' health promotion behavior through the above things. For this, author selected as 5th, 6th graders, 400 persons at 5 elementary schools located on Kyonggi province. This data utilized ANOVA, multiple regression analysis and correlation analysis by SPSS program. The findings of this study were as follows; First, there showed meaningful differences concerning their health promotion behavior according to students' demographic traits. There were a birth date, living standard, domestic environments etc. as a factors which influenced on their health promotion behavior. With this, from ex-past-facto verification for these variable factors, as their birth date was faster, living standard was higher, domestic environments was better, as their health promotion behavior was more promotive. Second, students' health promotion behavior marked 3.61 among total 5 paint with the respective to its fulfillment degree, their self-concept marked 3.45 among total 5 paint. Their mental health promotion behavior marked 3.71 with the respective to inferior category of health promotion behavior, which was the highest score. In the other hands, their physical health promotion behavior marked 3.71, social health promotion behavior marked 3.45. contrary the disease prevention, first-aid & safety, oral health, health & nutrition(P>.05). Third, there show meaningful difference, in the level of p-value <.001 with the respective to the correlations between primary school students' health promotion behavior and their self-concept, more their self-concept was positive, more their more their whole health promotion behavior(r=.479), the fulfillment degree of physical health promotion behavior(r=.384), mental health promotion behavior(r=.543), social health promotion behavior(r=.372) were high. Fourth, with the respective to the results of difference verification concerning their fulfillment degree of health promotion behavior according to the upper, middle, inferior group of self-concept, there showed statistically meaningful difference, in the level of p-value<.001. In the long run, more their self-concept was positive, more their whole health promotion behavior was high. With this, from the results of $Scheff\acute{e}$ verification, there showed meaning differences among the upper and middle group, upper and inferior group, middle and inferior group. Fifth, self-concept played the role as the most important prognostic factor with the respective to primary school students' health promotion behavior(23.0%), in the other hands, there showed positive weight of 24.0% concerning the fulfillment of whole health promotion behavior by domestic environments(1.0%). From the above results, primary school students' the fulfillment degree of health promotion behavior didn't reach to middle or inferior level. In the other hands, there showed positive effects in the correlations between self-concept and the fulfillment degree of health promotion behavior, and also high self-concept group was much positive considering inferior group in the fulfillment degree of health promotion behavior. Accordingly, more their self-concept was positive, more their fulfillment degree of health promotion behavior was effective. Eventually, in the future, there have to make an efforts to develope positive, substantial programs through their self-concept enhancement etc. in the adequate planning or operation for primary school students' health education and school health program.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.814-821
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• 2014

As a natural plant ingredients, glasswort (Salicornia herbacea L.) contains various physiological activities, mainly anti-oxidative and anti-diabetic activities. However, only a few studies have been carried out on its anti-adipogenic effect. This study investigated the anti-obesity effects of Salicornia herbacea L. on 3T3-L1 adipocytes. As adipogenesis of preadipocytes to adipocytes involves proliferation and differentiation of cells, we treated three concentrations (125, 250, and $500{\mu}g/mL$) of Salicornia herbacea L. water extracts (SLW) in both pre-processing and post-processing stages. When 3T3-L1 adipocytes were differentiated and dyed with Oil Red O, adipocytes size and the value of relative Oil Red O staining were reduced by all concentrations of SLW in post-processing stage. Following adipogenic differentiation, the concentration of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) in the cell supernatant significantly increased upon treatment with $125{\mu}g/mL$ of SLW and further rose at concentrations of 250 and $500{\mu}g/mL$ during post-processing stage. There was no significant difference in glycerol production upon SLW treatment. Leptin production significantly decreased at all SLW concentrations during post-processing stage, whereas peroxisome proliferator activated receptor-${\gamma}$ (PPAR-${\gamma}$) and adiponectin secretions were significantly enhanced. Overall results showed that SLW might have an anti-adipogenic effect via enhancement of TNF-${\alpha}$ production, which causes dedifferentiation and inhibits lipid accumulations in adipocyte. Furthermore, SLW might prevent diabetes and cardiovascular disease, as it reduces leptin secretion and enhances production of both PPAR-${\gamma}$ and adiponectin. However, further research is needed to elucidate the exact mechanism and bioactive compounds of glasswort.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.195-221
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• 2009

According to an industry report, a large number of organizations have invested in Organizational Information System(OIS) in the past few years. Several research results indicate that successful investments in OIS lead to productivity enhancement, while failed ones result in undesirable consequences such as financial losses and dissatisfaction among employees. In spite of huge investments, however, many organizations have failed in achieving the hoped-for returns from OIS. Thus, understanding user acceptance, adoption, and usage of new IS(Information Systems) is an important issue for IS practitioners. Indeed, study of the user acceptance of new information system has been one of the most important research topics in the contemporary IS literature. Several theoretical models are tested to examine 'user acceptance' and 'usage behavior' in IS context. While many research models incorporate 'ease of use' or 'usefulness' as important factors in explaining user acceptance, Technology Acceptance Model(TAM) has been one of the most widely applied models in user acceptance and usage behavior. Even in recent IS studies that employ theories of innovation diffusion in the area of IS implementation, a major focus has been on the user's perception of information technologies. In this research, we study 'voluntariness' as an important factor in IS acceptance by users. Voluntariness is defined as "the degree to which the use of the innovation is perceived as being voluntary, or of free will" When examining the diffusion of accepting OIS, a thoughtful consideration should be given to 'perceived voluntariness.' Current article has following research questions: 1) What models are appropriate to explain the success of OIS? and 2) How does the 'voluntariness' affect the success of OIS? In order to answer these questions, a research model is proposed to describe the detailed nature of association among three independent variables (IT usage level, task interdependency, and organizational support), a mediating variable (IS usage), a dependent variable (perceived performance), and a moderating variable(perceived voluntariness). The central claim of this article is that organizations hardly realize expected returns from OIS investments unless perceived voluntariness is effectively managed after operating OIS. As an example of OIS in this study we have selected the Intranet of Republic of Korea Air Force (ROKAF). ROKAF has implemented the Intranet in an attempt to improve communication and coordination within the organization. To test our research model and hypotheses, survey questionnaires were first sent out to 400 Intranet users. With the assistance of ROKAF, Intranet users were initially identified among its members, and subjects were randomly drawn from the pool. 377 survey responses were finally returned. The unit of measurement and analysis in this research is a personal level. Path analysis based on structural equation modeling was used to test research hypotheses. Construct validity represents accordance between the theoretical base concept of constructs and its measurement items. Tests for the reliability and discriminant validity are accepted, thus verifying our survey instrument. In this research, we have proposed a conceptual framework to highlight the importance of perceived voluntariness after organization deploys OIS. The results of our analysis present several key finding. First, all three independent variables (IT usage level, task interdependency, and organizational support) have significant effects on IS usage, which will eventually improve performance. Thus, IS usage plays a mediating role between antecedent variables (IT usage level. task interdependency, and organizational support) and performance improvement. Second, the effect of the task dependency was the highest for IS usage among the three antecedent variables. This is highly plausible since one of the Intranet's major capabilities is to facilitate communication among members within an organization. Accordingly, we conclude that the higher the task dependency, the higher Intranet usage. The effect of user's IT usage level was the second, while the effect of the organizational support was the third. Finally, the perceived voluntariness plays a pivotal role in enhancing perceived performance in personal level after launching the Intranet. Relationships among investigated variables were significantly different between groups with a high level and a low level of voluntariness. The impact of the Intranet usage on the performance was greater in the higher level voluntariness group than in the lower one. For the lower level voluntariness group, the user's IT usage had the highest effect on the Intranet usage among the three antecedent variables. In short, our study suggests that the higher the perceived voluntariness is the more IS usage will be. Perceived voluntariness was found to have a moderating effect on the relationships among user IT usage level, task interdependency, IS usage, and perceived performance, supporting all the hypotheses on the moderating effect. Most of all, user IT usage level has the strongest influence on IS usage, indicating that users with superior IT usage are more likely to enjoy a high level of perceived performance.

• Korean Journal of Environmental Agriculture
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• v.22 no.2
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• pp.100-110
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• 2003

This study was conducted to evaluate influence of chemical properties in the riparian on the species diversity and to get plant information for enhancement of natural purification in Mankyeong River. The concentration of total nitrogen was high in Jeonju and Sam stream, while that of total nitrogen showed the highest peak in Winter. Concentrations of $NH_4-N$ was $0.01{\sim}0.06\;mg/L$ in Gosan and Soyang stream. The water quality of upstream along with Mankyeong River was suitable for the irrigation source. The riparian vegetation was investigated by Zurich-Montpellier school's method from June, 2001 to September, 2002. The number of riparian plants were 59 families, 129 genera, 165 species, 20 varieties in Gosancheon, on the while 53 families, 111 genera, 141 species, 19 varieties in Soyangcheon. The number of riparian plants in Bari basin was higher than that of other sites namely, 73 families, 134 genera, 218 species, 33 varieties. Riparian vegetation was consisted of 12 plant communities. The contents of organic matter, total nitrogen and electrical conductivity had negative relationship with species diversity (Species richness index, Heterogeneity index, Species evenness index Species number). On the while, species diversity had positive relationship with soil pH. Species diversify of the plant communities were affected by topography and disturbance.

• Journal of Life Science
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• v.19 no.8
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• pp.1073-1080
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• 2009

A number of studies have demonstrated that the regular use of nonsteroidal anti-inflammatory drugs (NSAIDs) can reduce the risks of colorectal, oesophageal and lung cancers. NSAIDs have been shown to exert their anti-cancer effects through inducing apoptosis in cancer cells. The susceptibility of tumor cells to anti-tumor drug-induced apoptosis appears to depend on the balance between pro-apoptotic and anti-apoptotic programs such as nuclear factor kB (NF-kB), phosphatidylinositol 3-kinase (PI3K)-Akt/protein kinase B (PKB) and MEK1/2-ERK1/2 pathways. We examined the effects of pro-survival PI3K and ERK1/2 signal pathways on cell cycle arrest and apoptosis in response to NSAIDs including sulindac sulfide and NS398. We show that simultaneous inhibition of the Akt/PKB and ERK1/2 signal cascades could synergistically enhance the potential pro-apoptotic activities of sulindac sulfide and NS398. Similar enhancement was observed in cells treated with sulindac sulfide or NS398 and 100 ${\mu}$M genistein, an inhibitor of receptor tyrosine kinases (RTKs) that are upstream of PI3K and MEK1/2 signaling. We further demonstrate that NAG-1 is induced and plays a critical role(s) in apoptosis by NSAIDs-based combined treatment. In sum, our results show that combinatorialtreatment of sulindac sulfide or NS398 and genistein results in a highlysynergistic induction of apoptotic cell death to increase the chemopreventive effects of the NSAIDs, sulindac sulfide and NS398.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.169-175
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• 1998

Background: Heliox is known to decrease $PaCO_2$ in patients with increased airway resistance by increasing minute ventilation and reducing work of breathing(WOB). Besides these effect, heliox is expected to decrease functional anatomic dead space owing to improvement of peak expiratory flow rate(PEFR) and enhancement of gas distribution. We investigated whether heliox can decrease $PaCO_2$ even at the same minute ventilation (VE) and WOB with $N_2-O_2$ to speculate the effect of the heliox on the anatomic dead space. Material and Method: The subjects were 8 mechanically ventilated patients with asthma or upper airway obstruction(M : F=5 : 3, $68{\pm}10$years) who were under neuromuscular paralysis. The study was consisted of three 15-minutes phases: basal $N_2-O_2$ heliox and washout Heliox was administered via the low pressure inlet of servo 900C, and respiratory parameters were measured by pulmonary monitor(CP-100 pulmonary monitor, Bicore, Irvine, CA, USA). To obtain the same tidal volume(Vt) in heliox phase, the Vt on monitor was adjusted by the factor of relative flow rate of heliox to $N_2-O_2$. Dead space was calculated by Bohr equation. Results: 1) Vt, VE, peak inspiratory pressure(PIP) and peak inspiratory flow rate(PIFR) were not different between $N_2-O_2$ and heliox. 2) PEFR was higher on heliox($0.52{\pm}0.19$L/sec) than $N_2-O_2$($0.44{\pm}0.13$L/sec)(p=0.024). 3) $PaCO_2$(mmHg) were decreased with heliox($56.1{\pm}14.1$) compared to $N_2-O_2$($60.5{\pm}15.9$)(p=0.027). 4) Dead space ventilation(%) were decreased with heliox($73{\pm}9$ with $N_2-O_2$ and $71{\pm}10$ with heliox)(p=0.026). Conclusion: Heliox decreased $PaCO_2$ even at the same VE and WOB with $N_2-O_2$, and the effect was considered to be related with the reduction of anatomic dead space.

• Journal of The Korean Association For Science Education
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• v.37 no.4
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• pp.763-773
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• 2017

The purpose of this study is to investigate the impact of Argument-Based Inquiry (ABI) strategy on student's character competency. For this study, 51 grade 11 students (two classes) were selected to the role assignment (ABI-R group) and 46 students (two classes) were assigned to the non-role assignment group (ABI group). In the result, the role assignment group (ABI-R group) showed a statistically higher change in character competency than the group without role assignment (ABI group). Particularly, the ABI-R group has significantly higher grade than ABI group in empathy, responsibility, and respect among the sub-factors of character competency. However, in the case of the cooperation factor of character competency, the ABI group showed statistically significant higher grade than ABI-R group. The results of this study showed that Argument-Based Inquiry (ABI) as teaching and learning strategies in science can contribute to the enhancement of human character competency. In addition, we suggest that students should be actively involved in the class through role assignment, but it is necessary to present the class situation so that they can be actively engaged according to the problem situation rather than being fixed in a given role.