• Management & Information Systems Review
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• v.3
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• pp.287-316
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• 1999

Cyberspace permits us to more beyond traditional face-to-face, mail and telephone surveys, yet still to examine basic issues regarding the quality of data collection: sampling, questionnaire design, survey distribution, means of response, and database creation. This article address each of these issues by contrasting and comparing traditional survey methods(Paper-and-Pencil) with Internet or Personal Computer networks-mediated (Screen-and-Keyboard) survey methods also introduces researchers to this revolutionary and innovative tool and outlines a variety of practical methods for using the Internet or Personal Computer Networks. The revolution in telecommunications technology has fostered the rapid growth of the Internet all over the world. The Internet is a massive global network and comprising many national and international networks of interconnected computers. The Internet or Personal Computer Networks could be the comprehensive interactive tool that will facilitate the development of the skills. The Internet or Personal Computer Networks provides a virtual frontier to expand our access to information and to increase our knowledge and understanding of public opinion, political behavior, social trends and lifestyles through survey research. Comparable to other technological advancements, the Internet or Personal Computer Networks presents opportunities that will impact significantly on the process and quality of survey research now and in the twenty-first century. There are trade-offs between traditional and the Internet or Personal Computer Networks survey. The Internet or Personal Computer Networks is an important channel for obtaining information for target participants. The cost savings in time, efforts, and material were substantial. The use of the Internet or Personal Computer Networks survey tool will increase the quality of research environment. There are several limitations to the Internet or Personal Computer Network survey approach. It requires the researcher to be familiar with Internet navigation and E-mail, it is essential for this process. The use of Listserv and Newsgroup result in a biased sample of the population of corporate trainers. However, it is this group that participates in technology and is in the fore front of shaping the new organizations of interest, and therefore it consists of appropriate participants. If this survey method becomes popular and is too frequently used, potential respondents may become as annoyed with E-mail as the sometimes are with mail survey and junk mail. Being a member of the Listserv of Newsgroup may moderate that reaction. There is a need to determine efficient, effective ways for the researcher to strip identifiers from E-mail, so that respondents remain anonymous, while simultaneously blocking a respondent from responding to a particular survey instrument more than once. The optimum process would be on that is initiated by the researcher : simple, fast and inexpensive to administer and has credibility with respondents. This would protect the legitimacy of the sample and anonymity. Creating attractive Internet or Personal Computer Networks survey formats that build on the strengths of standardized structures but also capitalize on the dynamic and interactive capability of the medium. Without such innovations in survey design, it is difficult to imagine why potential survey respondents would use their time to answer questions. More must be done to create diverse and exciting ways of building an credibility between respondents and researchers on the Internet or Personal Computer Networks. We believe that the future of much exciting research is based in the Electronic survey research. The ability to communicate across distance, time, and national boundaries offers great possibilities for studying the ways in which technology and technological discourse are shaped. used, and disseminated ; the many recent doctoral dissertations that treat some aspect of electronic survey research testify to the increase focus on the Internet or Personal Computer Networks. Thus, scholars should begin a serious conversation about the methodological issues of conducting research In cyberspace. Of all the disciplines, Internet or Personal Computer Networks, emphasis on the relationship between technology and human communication, should take the lead in considering research in the cyberspace.

• Management & Information Systems Review
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• v.34 no.3
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• pp.17-39
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• 2015

This study examined the structural changes and volatility in the global stock markets using a Markov Regime Switching ARCH model developed by the Hamilton and Susmel (1994). Firstly, the US, Italy and Ireland showed that variance in the high volatility regime was more than five times that in the low volatility, while Korea, Russia, India, and Greece exhibited that variance in the high volatility regime was increased more than eight times that in the low. On average, a jump from regime 1 to regime 2 implied roughly three times increased in risk, while the risk during regime 3 was up to almost thirteen times than during regime 1 over the study period. And Korea, the US, India, Italy showed ARCH(1) and ARCH(2) effects, leverage and asymmetric effects. Secondly, 278 days were estimated in the persistence of low volatility regime, indicating that the mean transition probability between volatilities exhibited the highest long-term persistence in Korea. Thirdly, the coefficients appeared to be unstable structural changes and volatility for the stock markets in Chow tests during the Asian, Global and European financial crisis. In addition, 1-Step prediction error tests showed that stock markets were unstable during the Asian crisis of 1997-1998 except for Russia, and the Global crisis of 2007-2008 except for Korea and the European crisis of 2010-2011 except for Korea, the US, Russia and India. N-Step tests exhibited that most of stock markets were unstable during the Asian and Global crisis. There was little change in the Asian crisis in CUSUM tests, while stock markets were stable until the late 2000s except for some countries. Also there were stable and unstable stock markets mixed across countries in CUSUMSQ test during the crises. Fourthly, I confirmed a close relevance of the volatility between Korea and other countries in the stock markets through the likelihood ratio tests. Accordingly, I have identified the episode or events that generated the high volatility in the stock markets for the financial crisis, and for all seven stock markets the significant switch between the volatility regimes implied a considerable change in the market risk. It appeared that the high stock market volatility was related with business recession at the beginning in 1990s. By closely examining the history of political and economical events in the global countries, I found that the results of Lamoureux and Lastrapes (1990) were consistent with those of this paper, indicating there were the structural changes and volatility during the crises and specificly every high volatility regime in SWARCH-L(3,2) student t-model was accompanied by some important policy changes or financial crises in countries or other critical events in the international economy. The sophisticated nonlinear models are needed to further analysis.

• Radiation Oncology Journal
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• v.28 no.4
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• pp.238-248
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• 2010

Purpose: To compare the dose distributions between three-dimensional (3D) and four-dimensional (4D) radiation treatment plans calculated by Ray-tracing or the Monte Carlo algorithm, and to highlight the difference of dose calculation between two algorithms for lung heterogeneity correction in lung cancers. Materials and Methods: Prospectively gated 4D CTs in seven patients were obtained with a Brilliance CT64-Channel scanner along with a respiratory bellows gating device. After 4D treatment planning with the Ray Tracing algorithm in Multiplan 3.5.1, a CyberKnife stereotactic radiotherapy planning system, 3D Ray Tracing, 3D and 4D Monte Carlo dose calculations were performed under the same beam conditions (same number, directions, monitor units of beams). The 3D plan was performed in a primary CT image setting corresponding to middle phase expiration (50%). Relative dose coverage, D95 of gross tumor volume and planning target volume, maximum doses of tumor, and the spinal cord were compared for each plan, taking into consideration the tumor location. Results: According to the Monte Carlo calculations, mean tumor volume coverage of the 4D plans was 4.4% higher than the 3D plans when tumors were located in the lower lobes of the lung, but were 4.6% lower when tumors were located in the upper lobes of the lung. Similarly, the D95 of 4D plans was 4.8% higher than 3D plans when tumors were located in the lower lobes of lung, but was 1.7% lower when tumors were located in the upper lobes of lung. This tendency was also observed at the maximum dose of the spinal cord. Lastly, a 30% reduction in the PTV volume coverage was observed for the Monte Carlo calculation compared with the Ray-tracing calculation. Conclusion: 3D and 4D robotic radiotherapy treatment plans for lung cancers were compared according to a dosimetric viewpoint for a tumor and the spinal cord. The difference of tumor dose distributions between 3D and 4D treatment plans was only significant when large tumor movement and deformation was suspected. Therefore, 4D treatment planning is only necessary for large tumor motion and deformation. However, a Monte Carlo calculation is always necessary, independent of tumor motion in the lung.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.1-6
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• 2003

Immunoenhancing effects of conjugated linoleic acid (CLA) isomers (l0t-l2c CLA, 9c-11t CLA, CLA mixture, 9c-11c CLA and 9t-11t CLA) on chemotactic activity of porcine peripheral blood polymorphonuclear cells (PMN) were examined. The chemotactic activity of PMN was evaluated by a modified Boyden chamber assay. CLA isomers at higher concentration of 50 to 200$\mu$M exhibited a low viability of cells by trypan blue exclusion. CLA isomers were used at concentration of 20uM showing no cytotoxic effect and high cell viability. CLA isomers themselves were not active or slight chemotactic for PMN. But culture supernatant from mononuclear cells (MNC) treated with 10t-12c CLA, 9c-11t CLA and CLA mixture except for 9c-11c. CLA and 9t-11t CLA enhanced remarkably chemotactic activity or porcine PMN PMN migration by culture supernatant from MNC treated with CLA mixture was found to be true chemotaxis by checkboard assay. This migration was also induced by porcine recombinant interleukin (rIL)-8. PMN chemotaxis caused both culture supernatant from MNC treated with CLA mixture and porcine rIL-8 was inhibited in a dose-dependent manner by addition of anti-porcine IL-8 polyclonal antibody. Therefore, these results strongly suggested that CLA (10t-12c CLA, 9c-11t CLA and CLA mixture) could stimulate porcine MNC to release and IL-8 like chemotactic activity.

• Journal of Life Science
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• v.25 no.7
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• pp.826-832
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• 2015

This study describes the effects of activated charcoal on the removal of salts, detergents, and pigments from protein extracts of ginseng leaves and roots. Incubation of protein extracts with 5% (w/v) activated charcoal (100-400 mesh) for 30 min at 4℃ almost removed the salts and detergents including NP-40 as can be observed on SDS-PAGE. In addition, analysis of chlorophyll content showed significant depletion of chlorophyll (~33%) after activated charcoal treatment, suggesting potential effect of activated charcoal on removal of pigments too along with the salts and detergents. 2-DE analysis of activated charcoal treated protein samples showed better resolution of proteins, further indicating the efficacy of activated charcoal in clearing of protein samples. In case of root proteins, although not major differences were observed on SDS-PAGE, 2-DE gels showed better resolution of spots after charcoal treatment. In addition, both Hierarchical clustering (HCL) and Principle component analysis (PCA) clearly separated acetone sample from rest of the samples. Phenol and AC-phenol samples almost overlapped each other suggesting no major differences between these samples. Overall, these results showed that activated charcoal can be used in a simple manner to remove the salts, detergents and pigments from the protein extracts of various plant tissues.

• Journal of Life Science
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• v.20 no.3
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• pp.396-402
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• 2010

This study was designed to investigate the effects of 4 kinds of plant water extract mixture and garlic extract (PMC) administration on serum lipid metabolism in hypercholestrolemic rats. The normal group was administered a cholesterol free diet, the control group a 1% cholesterol diet, and each experimental group was given a diet of 1% cholesterol, 1% plant mixture and 0.3, 0.5, 0.7% garlic extract (PMC-I, PMC-II, PMC-III), respectively. Each diet was administered orally to SD-male rats for 4 weeks. Total cholesterol content decreased by about 20% with administration of PMC. Triglyceride content also decreased from 9.3 to 15.0% compared to the control group, and phospholipid was similar to triglyceride. There was no significant difference in HDL-cholesterol content between the control and experimental groups. LDL-cholesterol content of the normal group was 9.4 times lower than the control group and its content was significantly lower in the PMC-II ($68.45{\pm}12.83\;mg/dl$) and PMC-III ($66.35{\pm}5.18\;mg/dl$) groups than the PMC-I group. VLDL-cholesterol content of the PMC-II and III groups were similar to the normal group. Atherogenic index (AI) and cardiac risk factor (CRF) were significantly lower in the PMC group. Blood glucose content was the lowest in the PMC-II ($189.37{\pm}12.02\;mg/dl$) group among all groups tested. Total protein content was $9.56{\pm}0.87{\sim}10.05{\pm}2.69\;mg/dl$ in the PMC-I~III groups and was significantly higher than the normal group. CPT activity did not show a significant difference among the experimental groups, while COT activity was effective only in the PMC-I group. Serum TBARS content in the PMC-III group was lower than in the normal group. Serum antioxidant activity by DPPH radical scavenging was $83.75{\pm}2.32%$ in the PMC-III group, which was significantly higher than the control group.

• Journal of Life Science
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• v.24 no.8
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• pp.827-836
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• 2014

There is a rising trend in obesity due to various factors, including changes in eating habits, lack of exercise, and genetic and psychological factors. Citrus peel has been reported to prevent obesity via antioxidative, antihypertensive, and LDL cholesterol-lowering effects. This study investigated the effects of citrus peel extract fermented with or without Aspergillus oryzae in a mouse model of diet-induced obesity. The animals were divided into four groups: a high-fat diet group (HFD), a normal fat diet (NFD) group, a citrus peel extract (CP) group, and a citrus peel extract fermented with A. oryzae (CPA) group. The citrus peel extract improved lipid metabolism and weight loss in the high-fat diet-induced obese mouse model. As expected, the body weight was higher in the HFD group compared with the NFD, CP, and CPA groups. However, the concentrations of total cholesterol (TG) and triglyceride (TC) in the serum and liver of the CP and CPA groups were lower than in the HFD group. There were no significant differences in the HDL cholesterol concentration among the groups. Taken together, our results suggest that extract of citrus peel biotransformed with A. oryzae had more antiobesity activity than citrus peel not transformed by A. oryzae through the fermentation of metabolites.

• Hwankyungkyoyuk
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• v.6 no.1
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• pp.63-99
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• 1994

The international environmental activities and environmental education began in 1970's. Environmental education in Korea was emphasized since the Forth National Curriculum. 'The Environmental Education Curriculum' will be separated as one of the most important parts in the Sixth National Education Curriculum in Korea. The purpose of this study was development. of 'Environmental Science' of high school appropriate to Sixth National Education Curriculum. First step was to state goals of environmental education in detail based on analysis of goals about environmental education in our country and other countries. Second was to analyse seven environments-related texts of Korea, America and England. Third, to measure how much environmental education has achieved in Fifth National Curriculum of Korea. Fourth, to develop a new environmental text of high school level. Fifth, to verify the effect of developed environmental text. The environmental part of 'Science I'(unit V. Life and Environments) and high school environments-related reference text(Survival and Environments) in Korea, American knowledges. American 'Environments' was stressed in many skills but they didn't include various teaching strategies. On the other hand, American 'Science-Technology-Society(S-T-S)' and British 'Science and Technology in Society(SATIS)' were stressed in knowledges and skills, and they included many teaching strategies and student actions. American 'S-T-S' was the only one stressed in values and attitudes. And all seven texts were not interested in behaviors and participations. To measure the achievement of environmental education by questionnaire, 497 high school students in total were selected from five different schools. Actually, most students had a positive thinkings and attitudes in their hearts about environmental problems, about environmental problems, but many of them did not take actions to solve environmental problems and to protect environments. The higher the score students got in 'knowledges and informations', the higher the score in 'skill'. It implies that learning of skills is based on learning of knowledges and informations about environments. On the other hand, much knowledges and information about environments has not always ensured positive thinkings and attitudes or active behaviors and participations to solve environmental problem. In view that ultimate aim of environmental education is forming responsible environmental behaviors and the goals of values and behaviors are as important as knowledges and skills. A new environmental text of high school level was developed and it was based on analysis of seven texts and environmental education in Fifth Korean Curriculum. This text have seven units, 1. Habitates : What're the meanings?, 2. Nuclear Energy : Can't be Avoid?, 3. Acid Rain : What're the Messages?, 4. Ethanol : Is this Future Fuel?, 5. Wastes : A New War!, 6. What're the National and Gloval Environmental education and avoided from the array of knowledges. Therefore included various teaching strategies and independent actions of students. 'Open-ended value learning' and 'free behavior learning' in text were special learning parts for aquisition of values and formation of behaviors. To verify the effects. of new developed environmental text, the direct learning was carried out by 286 students in total. Post test scores of experimental groups per each units were significantly higher than those of control groups from five different schools were as follows. For validity of selecting contents for units, 74% of respondent replied positively. For classification and presentation of four goal-groups, 90% replied positively in validity and 82%, in utility. For validity of various teaching strategies, 88% and for the degree of including student-centered independent actions, 86% replied positively, For importances and expected effects of 'open=ended value learning' and 'free behavior learning', showed positive responses respectively, 88%, 92% Therefore this text is effective to achieve four goals of environmental education equally.

• The Korean Journal of Food And Nutrition
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• v.29 no.3
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• pp.382-391
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• 2016

The purpose of this experiment was designed to investigate the effects of medicinal herbs (MH) extracts on dementia induced by trimethyltin chloride (TMT) in rats. Six-week-old male Sprague-Dawley rats were randomly divided into five groups; normal group (group 1), control group (group 2), MH extracts group (250, 500 mg/kg) (group 3, group 4) and positive control group (tacrine group, group 5). In the control group to induce dementia, a 2.5 mg/kg of TMT intraperitoneal injection was used for 14 days (1 per day) in the rats. In the MH extracts group 250 mg/kg and 500 mg/kg of MH extracts were medicated in an oral inoculation for 20 days (1 per day). After 30 minutes, a 2.5 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). In the positive control group (Tacrine group) 10 mg/kg of Tacrine, the dementia treatment, was medicated in an oral inoculation. After 30 mintues, 1 mg/kg of TMT intraperitoneal injection, which causes dementia, was used for 14 days (1 per day). The present author observed the passive avoidance performance test, and memory ability test (Y maze test), the values of MDA, acetlycholinesterase (AchE) activity in the brain and antioxidant enzyme in serum. MH extracts significantly improved memory of AD model rats in the Y-maze test, and also significantly improved memory of AD model rats in the passive avoidance test. MH extracts significantly reduced AChE activity, and significantly increased the SOD level, but not catalase and MDA. From the results above, MH extracts is thought to be effective in the improvement of antioxidant enzymes and memory ability.

• Korean Journal of Food Science and Technology
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• v.28 no.6
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• pp.1104-1110
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• 1996

To lessen the initial level of microorganism in kimchi, the preparation method of seasoning mixture was modified and electrolyzed acid-water was substitute for washing water and brine water. Changes in the microbial counts of the red pepper powder-garlic mixture prepared with red pepper powder, garlic and 4.8% (w/w) water (tap water and electrolyzed acid-water) of manufactured kimchi showed that coliform count and E. coli count were reduced to 93% and 98%, of the initial level in the tap water added red pepper powder-garlic mixture and 97% and 99% in the electrolzed acid-water added mixture after 6 hours of mix. After 24 hours of mix, no E. coli was recovered in borth mixtures. Microbial levels were revealed as $2.4{\times}10^5\;CFU/g$ for total count, $2.3{\times}10^5\;CFU/g$ for Lactobacillus count. $1.0{\times}10^2{\;}CFU/g$ of coliform count and $10^1\;CFU/g$ of E. coli count in the seasoning mixture prepared by the general method, and $4.2{\times}10^5\;CFU/g$ of total count, $4.0{\times}10^5CFU/g$ of Lactobacillus count, $1.0{\times}10^3\;CFU/g$ of coliorm count and $4.0{\times}10^2\;CFU/g$ of E. coli count in the mixture propared by the modified method. During fermentation at $10^{\circ}C$, the levels of total and Lactobacillus counts in kimchi prepared by the modified method were significantly lower than those of kimchi were recovered in kimchi prepared by the modified method, whereas there were at the level of $10^1\;CFU/g$ in kimchi prepared by the general method. The pH and acidity of kimchi prepared by the modified method were 4.66 and 0.54%, respectively, whereas those in kimchi prepared b the general method were 4.51 and 0.70%, respectively. But after 14 days of fermentation significant differences were not observed in the changes of microbial, pH and acidity for both kimchi.