• Bulletin of the Korean Chemical Society
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• v.29 no.4
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• pp.790-794
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• 2008

Nucleophilic addition reaction of benzenethiols (PhSH) to 1-(2-nitrovinyl) benzenes ($\beta$ NS) in the presence of triethylamine (TEA) has been studied in acetonitrile at 25 ${^{\circ}C}$. The rate is first order with respect to [PhSH], [TEA] and [$\beta$ NS]. The reaction is found to proceed with the formation of ion-pair between benzenethiol and TEA. A suitable mechanism with the formation of an adduct between ion-pair and substrate in a slow step followed by its rearrangement to 1,2-addition product in a fast step has been proposed and corresponding rate law derived. From the rate law, the rate constants for the interaction between ion-pair and $\beta$NS have been evaluated. Interestingly, in both para-substituted substrates and benzenethiols the rate increases with the electron-withdrawing power of the substituents. The positive sign of $\rho_x$ in benzenethiols has been explained. The magnitude of cross-interaction constant, $\rho_{xy}$ is small (0.08). The magnitude of the Hammett $\rho_x$ values is higher than that of the Bronsted, $\beta_x$ values for benzenethiols. The kinetic isotope effect, $k_H/k_D$, is found to be greater than unity. A suitable transition state with simultaneous formation of $C_\beta$ -H and $B_\alpha$ -S bonds involving the ion-pair and $\beta$NS in a single concerted step has been proposed to account for these observations.

• Journal of Ginseng Research
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• v.34 no.4
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• pp.304-313
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• 2010

This study was undertaken to discover the effects and possible mechanisms of the effect of red ginseng extract (RGE) on spontaneous sleep. The effects of a low dose (10 mg/kg) and a high dose (200 mg/kg) of RGE were compared in rats. After recovery from a surgical operation enabling electroencephalograms recordings, rats were administered RGE orally. RGE was administered orally for 1 day or once per day for 5 days in either 10 or 200 mg/kg doses. Polygraphic signs were recorded for 12 h after oral administration of RGE. Both treatment with a large dose (200 mg/kg) of RGE for one day and treatment with either a large or a small dose for 5 days reduced the number of sleep.wake cycles. Daily treatment with RGE (either 10 or 200 mg/kg) for 5 days augmented NREM and total sleep, but reduced wakefulness. Delta wave activity recorded during non-REM (NREM) sleep and REM sleep was increased after one treatment with RGE (either 10 or 200 mg/kg). Delta wave activity during NREM was enhanced after daily treatment with RGE (either 10 or 200 mg/kg) for 5 days. Both alpha and beta subunits of the $\gamma$-aminobutyric acid $(GABA)_A$ receptor were significantly over-expressed in the hypothalamus of the RGE-treated groups. Moreover, the expression of glutamic acid decarboxylase was also increased in the hypothalamus. These results demonstrate that RGE may regulate spontaneous sleep via $GABA_A$ergic systems.

• Korean Journal of Clinical Pharmacy
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• v.3 no.1
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• pp.79-88
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• 1993

Bioequivalence(BE) test of commercially available sustained release tablets of diltiazem hydrochloride(DTZ) was performed to give some guidelines to BE test in korea in case of which drugs with low oral bioavaiiability(BA) due to substantial first-pass hepatic loss form pharmacologically active metabolites. In such cases, the pharmacologic activity after oral administration is greater than anticipated from BA data, based on chemical assay of drug alone. Therefore, this paper explores the use and meaning of area under the plasma concentration-time(AUC) data of parent and its metabolites to access BA if sustained release tablets. Normal healthy male volunteers(n=14) were randomly divided into 2 groups, and sustained release reference$(Herbesser^{(R)})$ and test$(Herben^{(R)})$ tablets of DTZ-30mg were given orally by balanced two-period cross-over dosing schedule. The plasma concentration of DTZ and and its active metabolite, desacetyldiitiazem(DAD), were determined by high performance liquid chromatography, and, $AUC_{DTZ},\;AUC_{DAD},\;AUC_{DTZ+DAD},\;C_{max}\;and\;T_{max}$ obtained. Analysis of varlance(ANOVA) showed that $AUC_{DTZ}\;and\;C_{max}$ passed the standard $(\alpha=0.05,\;1-\beta\geq0.8,\;\Delta\leq0.2)$ of BE test of korea, but $AUC_{DAD}$ was not satisfied from the standpoint of power. On the other hand, $AUC_{DTZ\midDAD}$ may be more avaliable than $AUC_{DAD}$ from the standpoint of statistics and pharmacologic equivalence.

• Journal of Korean Academy of Nursing Administration
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• v.19 no.4
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• pp.513-524
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• 2013

Purpose: This study was conducted to identify ethical climate factors in hospitals and analyze their influence on job satisfaction and organizational commitment. Methods: A convenience sample of 196 nurses from one national university hospital in J city participated in this descriptive study survey. Instruments included the Ethical Climate Questionnaire, Job Satisfaction Scale, and Organizational Commitment Scale. Cronbach's ${\alpha}$ and factor analysis were done to test reliability and construct validity of the scales. Data were collected from March 15 to March 25, 2013 and analyzed using descriptive statistics, one-way ANOVA, t-test, Pearson correlation, and multiple regression with SPSS/WIN 18.0. Results: Seven ethical climate factors were identified; laws and professional codes, social responsibility, company rules and procedures, self-interest, personal morality, efficiency, and friendship. Factors influencing job satisfaction were friendship (${\beta}$=.25), social responsibility (${\beta}$=.20), laws and professional codes (${\beta}$=.20), and educational level (${\beta}$=.27), explaining 37.6% of variance in job satisfaction. Factors influencing organizational commitment included social responsibility (${\beta}$=.29), friendship (${\beta}$=.27), laws and professional codes (${\beta}$=.23), and age (${\beta}$=.19), with explanatory power of 44.6%. Conclusion: Results can be used as preliminary data for developing new strategies to establish positive ethical climates in hospital environments and thus enhance nurses' job satisfaction and organizational commitment.

• Journal of The Korean Association For Science Education
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• v.31 no.6
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• pp.920-930
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• 2011

This research was executed in order to analyze the factors and strengths of learning difficulties that science-gifted high-school students experienced in Korea Science Academy. The subjects are 284 gifted high-school students from Korea Science Academy who responded to a paper-and-pencil questionnaire survey. The questionnaire used in this research was developed by focusing on the difficulties in the learning situations of science-gifted highschool students based on Rhodes' 4P theory of creative achievement. The data was analyzed using cross-tabulation analysis, frequency analysis, MANOVA by the SPSS 12.0 program. The analysis of the questionnaire survey on the learning difficulties showed (i) a grade difference in interpersonal relationship and (ii) gender differences in learning ability and learning strategies. Also, it was observed that the students tried to solve their learning difficulties most frequently by meeting their school peers except for methods of 'the others' such as relying on religious power.

• PNF and Movement
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• v.17 no.3
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• pp.441-450
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• 2019

Purpose: This study identified the co-activation of quadriceps and hamstring muscles during hamstring strengthening exercises in healthy adults. Methods: Twenty-one participants were required for the present study design to achieve 80% power, 0.8 effect size (η2), and an alpha level of 0.05. Thus, this study recruited 21 healthy adults. All participants performed Nordic exercises, bridge exercises, and one-leg deadlifts randomly. The activity of the rectus femoris, vastus medialis (VM), vastus lateralis (VL), biceps femoris (BF), and semitendinosus (SM) were measured. In addition, the ratios of VM/VL and hamstring/quadriceps (HQ) were measured during the three hamstring strengthening exercises using electromyography. One-way ANOVA was used to compare the co-activation of quadriceps and hamstring muscles in the three exercises. Results: The activity of VM and VL during the performance of one-leg deadlifts was significantly higher than the other two exercises. The BF had significantly higher activity during the Nordic exercises compared to the other two exercises. In addition, the SM activation was significantly greater during Nordic exercises than one-leg deadlifts. Additionally, there was significant difference in HQ ratio among hamstring strengthening exercises. In specific, the one-leg deadlifts yielded a significantly lower HQ ratio. Conclusion: This study revealed that one-leg deadlifts are effective in rehabilitation for anterior cruciate ligament injury. In addition, Nordic exercises can be recommended to facilitate hamstring muscle activation.

• Journal of Environmental Health Sciences
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• v.23 no.4
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• pp.115-120
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• 1997

The purpose of thesis was to investigate the removal efficiency of surfactants and commercial detergents by Oenanthe javanica that is one of aquatic plants in Korea. The experiment is concerned with measuring the concentrations of surfactants and commercial detergents in different media: 1) in pure water, 2) in water containing Oenanthe javanica, 3) in water containing Oenanthe javanica and commercial nutrients. The surfactants used in this research include linear alkylbenzene sulfonates (LAS), $\alpha$-sulfo fatty acid methyl esters(MES), and alkylbenzene sulfonates(ABS). Two commercial detergents designated as A and B were in the forms of power and liquid. The results showed that LAS and MES were more effectively removed by Oenanthe javanica probably because these have a chain of linear carbon than on ABS with a branched carbon structure. In the case of commercial detergents, when the except was performed on the basis of surfactants proportion, the removal trends were similar to LAS and MES. The 5-day cultivating test with initial concentration of 0.5-1.0 ppm surfactants showed that less than 10% was removed if no nutrients an Oenanthe javanica were added. When Oenanthe javanica was added into the sample solution containing surfactants, the removal efficiency was increased 100% for the solution containing 0.5-1.0 ppm 60-70% for 5-10 ppm. In addition, chlorisis on Oenanthe javanica was observed due to surfactants and commercial detergents for all three cases. To test the dependence of population density on nutrients, the initial population density was made 300 g/0.4 m$^2$. Throughout the 5-day experiment, the on Oenanthe javanica grew 20-25% with 0.5-1.0 ppm without the synthetic nutrients but by 5% with a high concentrations of 5-10 ppm. The population density was appeared to be independent of synthetic nutrients. The leaves were to be grown with synthetic nutrients, while roots were grown without synthetic nutrients. Based on this research, the fundamental data concerning cultivation and an adequate adjustment of the water condition can provide for the utilization of Oenanthe javanica in real water treatment system.

• Journal of the Korean Home Economics Association
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• v.31 no.1
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• pp.181-192
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• 1993

This study was undertaken to investigate the factorial structure of clothing purchase motives, and to examine the relationship between clothing purchase motives, self-concept, and post-purchase clothing satisfaction of males. Questionnaire was comprised of three sections: 25 Likert type statements of clothing purchase motive measure; post-purchase clothing satisfaction measure; and three self-concepts measure(physical, personal, and social self-concept). For the measurement of self-concepts, a portion of‘Self-Concept Scale’by Wonshik Chung was used. Samples were 312 male white collar workers in Seoul, whose age were ranged from 20 to 39. the data were analyzed using factor analysis, Cronbach's alpha reliability coefficient, Pearson's correlation coefficient, and multiple regression analysis. The results of the study were the followings: 1. Six factors of clothing purchase motives derived by factor analysis. 21 items having a factor loading of ± .40 or higher were given consideration in the interpretation of each factor: F.1‘clothing dsign’; F.2‘fashion and impulsive buying’, F.3‘clothing utility’; F.4‘others influence’: F.5‘financial margin’; F.6‘clothing’2. Male consumers perceived the purchase motive of‘clothing design’to be the most important,‘clothing deficiency’the second important, and‘others influence’the least important. 3. Physical, personal, and social self-concept had positive relations to the purchase motive of‘clothing design’and negative relations to the‘clothing deficiency’. Physical self-concept had negative relation to the motive of‘others influence’. 4. Male consumers high in physical, personal, and social self-concept had more positive attitude in the evaluation of post-purchase clothing satisfaction. 5. Post-purchase clothing satisfaction was influenced most by the purchase motive of‘clothing design’, and next by physical self-concept, and age. Age of subjects had negative relation to post-purchase clothing satisfaction. The explanatory power of the 3 variables was 19.9%.

• Journal of Korean society of Dental Hygiene
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• v.18 no.2
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• pp.227-237
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• 2018

Objectives: This study aims to recognize the importance of dental hygiene process diagnosis of dental hygiene process which can comprehensively grasp the patient's problem and to use it as a basis for establishing the patient's preventive treatment plan. Methods: This study did survey to 443 patients who received treatment based on the oral health care program from a dental clinic in Busan from January 2015 to January 2017. Data analysis was performed using IBM SPSS Statistics (Version 21.0), and statistical significance level was set at ${\alpha}=0.05$. Binary logistic regression analysis was performed to the dental hygiene problems affecting the dental hygiene plan. Results: There were significant differences in dental hygiene problems between male and female respondents on various dental problems such as dental plaque deposition, attrition, stain, dental fear, possibility of jaw joint disorder, food pressing, possibility of malocclusion. There were also significant differences in dental hygiene plans between male and female respondents in air-Jet, non-smoking education, and sealant. The most common dental hygiene plan was scaling, The problem of stain showed that the scaling plan was 0.20 times less. The explanatory power of the model was 43.5%, and the Hosmer and Lemeshow tests were 0.345. Conclusions: Therefore, if we continue to study the factors affecting the dental hygiene problems and the plan, we can reduce the burden of the dental hygienists applying the dental hygiene process in the dental clinic. And, it is expected that the oral health care program using the dental hygiene process will spread to the dental clinic as an excellent oral preventive program.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.1
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• pp.76-85
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• 2010

In general, anesthetic depth is evaluated by experience of anesthesiologist based on the changes of blood pressure and pulse rate. So it is difficult to guarantee the accuracy in evaluation of anesthetic depth. The efforts to develop the objective index for evaluation of anesthetic depth were continued but there was few progression in this area. Heart rate variability provides much information of autonomic activity of cardiovascular system and almost all anesthetics depress the autonomic activity. Novel monitoring system which can simply and exactly analyze the autonomic activity of cardiovascular system will provide important information for evaluation of anesthetic depth. We investigated the anesthetic depth as following 7 stages. These are pre-anesthesia, induction, skin incision, before extubation, after extubation, Post-anesthesia. In this study, temporal, frequency and chaos analysis method were used to analyze the HRV time series from electrocardiogram signal. There were NN10-NN50, mean, SDNN and RMS parameter in the temporal method. In the frequency method, there are LF and HF and LF/HF ratio, 1/f noise, alphal and alpha2 of DFA analysis parameter. In the chaos analysis, there are CD, entropy and LPE. Chaos analysis method was valuable to estimate the anesthetic depth compared with temporal and frequency method. Because human body was involved the choastic character.