• Korean Journal of School Psychology
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• v.18 no.3
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• pp.291-316
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• 2021

This study was conducted to identify how special education teachers perceive their school's organizational climate through latent profile analysis performed using Mplus, and determine whether there was a difference in the average teacher burnout rate between perception groups using three-step approaches. The participants were 312 special education teachers. The perception groups were identified as 'closed', 'laissez-faire', 'average', 'controlled', and 'autonomous.' The groups had different teacher burnout rates. The closed group had the highest rate, while the autonomous group had the lowest. This paper discusses the implications of these results for special education teacher burnout and school organizational climate, and suggests ideas for future studies.

• Journal of Chest Surgery
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• v.21 no.5
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• pp.828-841
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• 1988

To predict the postoperative hemodynamic status of right ventricle preoperatively, a retrospective analysis was undertaken to determine the influence of pulmonary artery size on postoperative right ventricular pressure in 32 consecutive patients with tetralogy of Fallot who underwent total correction between July, 1987 to June, 1988 at the Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital. We have related the ratio of the postrepair peak systolic pressure in the right ventricle and the systemic systolic arterial pressure[PRV/Ao] to the preoperative cineangiographic measurement of pulmonary arterial tree, expressed as pulmonary artery index[PAI], the ratio of diameter of the right pulmonary artery to diameter of ascending aorta[r.PA/A.Ao], the ratio of right and left pulmonary artery to diameter of descending aorta[r.I.PA/D.Ao] There was tendency that the postrepair PRV/Ao seems to be related to the preoperative diameter of right and left pulmonary artery, but there were no statistically significant correlation with PAI, r.PA/A.Ao, r.l.PA/D. Ao to the ratio of the postoperative peak systolic right ventricular pressure and systemic systolic arterial pressure[PRV/Ao]. There was tendency to decrease the postoperative right ventricular pressure[PRV/Ao] about 11.2%[P < 0.025] within several hours than immediately after repair, but after then, there was no change of right ventricular pressure[PRV/Ao] significantly. There was good correlation of pressure change between the immediate and late postrepair right ventricular pressure[48 hour], and the derived linear regression line was; y=0.68534 0.1994[r=0.57294, P < 0.001]. There was no operative death due to residual high right ventricular pressure[PRV/Ao >0.75] related to hypoplastic pulmonary arterial development, thus we expect, for symptomatic patients even infants, that complete repair can be attempted when the pulmonary artery index[PAI] is over 108mm2/BSA, RPA/AAo is over 0.35, RPA LPA/D. Ao is over 1.36.

• Membrane Journal
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• v.11 no.3
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• pp.124-132
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• 2001

Silica membranes were prepared on a porous ${\alpha}$-alumina tube with pore size of 150nm by sol-gel and chemical vapor deposition(CVD) method for hydrogen separation at high temperatures. Silica and ${\gamma}$-lumina membranes formed by the sol-gel method possessed a large amount of mesopores of a Knudsen diffusion regime. In order to improve the $H_2$ selectivity, silica was deposited in the sol-gel derived silica/${\gamma}$-alumina layer by thermal decomposition of tetraethyl orthosilicate(TEOS) at $600^{\circ}C$. The CVD with forced cross flow through the porous wall of the support was very effective in plugging mesopores that were left unplugged in the membranes. The CVD modified silica/alumina composite membrane completely rejected nitrogen permeation and thus showed a high $H_2$ selectivity by molecular sieve effect. the permeation of hydrogen was explained by activated diffusion and the activation energy was 9.52kJ/mol.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.237-254
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• 2021

Objectives: This study aims to classify the latent profiles in the exposure to hazard factors of salaried employees and test the determinants. Methods: Latent profile analysis(LPA) was conducted using data from the fifth Korean Working Conditions Survey(KWCS). 30,050 of salaried employees were the subjects of this study. After classifying the employees, multinomial logistic regression was used to test the determinants. Results: Salaried employees were classified with three latent profiles based on the exposure to the hazard factors. Employees included in class 1(32.8%) tend to experience low level of physical hazard factors, moderate level of psychological hazard factors, and high level of office work hazard factors. Employees included in class 2(61.8%) tend to be exposed to the moderate to high level of physical hazard factors, moderate to low level of psychological hazard factors, and low level of office work hazard factors. Employees included in class 3(5.4%) tend to experience high level of psychological and physical hazard factors, and moderate level of office work hazard factors. After classification, the demographic, health-, and employment-related variables were tested. Conclusions: This study clarified the features of each class, and proved that employees in class 3 are quite hazardous in that they are exposed to physical and psychological hazard factors much more frequently than other employees. Thus, this study can be used in predicting the high-risk employees and taking preemptive measures for preventing industrial accidents.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.16 no.1
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• pp.37-53
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• 2021

The purpose of this study is to analyze the types of latent profiles depending on the job satisfaction of youth entrepreneurs in South Korea and examine the influence of related variables. Latent profile analysis (LPA) was conducted using data from the 12th year of the Youth Panel Study. Results of the study revealed that there were five latent profiles based on job satisfaction among young entrepreneurs: lowest job satisfaction, mid-low job satisfaction, middle job satisfaction, mid-high job satisfaction, and highest job satisfaction. By applying multinomial logistic analysis, the influencing factors for each latent profiles have been derived. Gender, marital status, subjective health, self-esteem, entrepreneurial motivation, difficulty in start-up, person-job fit, intrinsic or extrinsic job values, business scale, income, work hour, education or training, and labor insurance were significant predictors of youth entrepreneurs' job satisfaction. Based on these results, the article discusses practical implications that can enhance the job satisfaction of young entrepreneurs.

• Journal of fish pathology
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• v.20 no.2
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• pp.119-127
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• 2007

Phosphoinositide-specific phospholipase Cδ (PLCδ) plays an important role in many cellular responses and is involved in the production of second messenger. The present study was conducted to characterize the catalytic and regulatory properties of the PLCδ of Misgurnus mizolepis (ML-PLCδ). The ML-PLCδ gene was cloned and expressed under according to the method of the previous report (Kim et al., 2004), and its recombinant protein was purified by successive chromatography using Ni2+-NTA affinity column. The recombinant ML-PLCδ showed a concentration-dependent PLC activity to phosphatidylinositol 4,5-bisphosphate (PIP2) or phosphatidylinositol (PI). Its activity was absolutely Ca2+-dependence, which was similar to mammalian PLCδ isozymes. The Ca2+ concentration yielding maximal activation of ML-PLCδ was 100 μM. However, the activity was decreased interestingly by a polyamine, such as spermine and spermidine. In vitro assay using cholate-micelle cell, ML-PLCδ activity was inhibited in dose-dependent manner by sphinogosine but increased by phosphocholine . In the lipid-binding assay, ML-PLCδ was strongly bound to LPA, PI(3)P, PI(4)P, PI(5)P, PI(3,5)P2, PI(4,5)P2, PI(3,4,5)P3 and PA, but it showed the low affinity to S1P, PI(3,4)P2 and PS. Taken together our results, it is suggested that the general catalytic and regulatory properties of ML-PLCδ are similar with those of mammalian PLCδ1 isozymes, but the N-terminal extended piscine phospholipase Cδ1 (ML-PLCδ) might reflect some distinctions in regulatory properties and inositol-lipid binding specificity between piscine ML-PLCδ and mammalian PLCδ isozymes.

• Tuberculosis and Respiratory Diseases
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• v.48 no.3
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• pp.347-356
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• 2000

Background : Patients with obstructive sleep apnea syndrome are known to have high long-term mortality compared to healthy subjects because of their cardiovascular dysfunction. The observation of hemodynamic changes by obstructive apneas is helpful when attempting to understand the pathophysiological mechanism of the development of cardiovascular dysfunction in those patients. Therefore, we studied the changes in cardiovascular function with an animal model and tried to obtain the basic data for an ideal experimental model (this phrase is unclear), a requirement for a more advanced study. Methods : Sixteen anesthetized dogs with ${\alpha}$-chloralose delete were divided into two groups : 8 dogs of room air breathing group and 8 dogs of oxygen breathing group. We measured $PaO_2$, $PaCO_2$, heart rate, cardiac output, mean femoral artery pressure, and mean pulmonary artery pressure at specified times during the apnea-breathing cycle before endotracheal tube occlusion (baseline), 25 seconds after endotracheal tube occlusion (apneic period), 10 seconds (early phase of postapneic period, EPA) and 25 seconds (late phase of postapneic period, LPA) after spontaneous breathing. Results : In room air breathing group, the heart rate significantly decreased during the apneic period compared to that at baseline (P<0.01) and increased at EPA and LPA compared to that during the apneic period (P<0.01). But, the heart rate showed no significant changes during apneic and postapneic periods in the oxygen breathing group. Cardiac output tended to decrease during apneic period compared to that at baseline, but was statistically significant. Cardiac output significantly decreased at LP A compared to at baseline (P<0.01). Mean femoral artery pressure was significantly decreased at during apneic period compared to that at baseline (P<0.05). Conclusion : Through this experiment, we were partially able to understand the changes of cardiovascular function indirectly, but delete new experimental animal model displaying physiological mechanism close to natural sleep should be established, and the advanced study in the changes of cardiovascular function and their causes should be continued.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.1
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• pp.24-36
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• 2003

The digital mobile communication will be developed till getting multimedia service in anyone, any where, any time. Theses requiring items are going to be come true via IMT-2000 system. Transmitting signal bandwidth of IMT-2000 system is 3 times as large as IS-95 system. That is mean peak to average of signal is higher than IS-95A system. So we have to design it carefully not to effect in adjacent channel. HPA(High Power Amplifier) located in the end point of system is operated in 1-㏈ compression point(Pl㏈), then it generates 3rd and 5th inter modulation signals. Theses signals affect at adjacent channel and RF signal is distorted by compressed signal which is operated near by Pl㏈ point. Then the most important design factor is how we make HPA having high linearity. Feedback, Pre-distorter and Feed-forward methods are presented to solve theses problems. Feed-forward of these methods is having excellent improving capacity, but composed with complex structure. Generally, Linearity and Efficiency in power amplifier operate in the contrary, then it is difficult for us to find optimal operating point. In this paper we applied algorithm which searches optimal point of linear characteristics, which is key in Power Amplifier, using minimum current point of error amplifier in 1st loop. And we made 2nd loop compose with new structure. We confirmed fabricated LPA is operated by having high linearity and minimum current condition with ACPR of -26 ㏈m max. @ 30㎑ BW in 3.515㎒ and ACLR of 48 ㏈c max@${\pm}$㎒ from 1W to 40W.

• Korean Journal of Culture and Social Issue
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• v.25 no.4
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• pp.325-351
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• 2019

The present study examined patterns of co-occurrence between DSM-5 posttraumatic stress disorder(PTSD) symptoms and posttraumatic growth(PTG) among Korean populations(n= 860). Latent profile analysis was used to identify subclasses and suggested that the 3-class model fit best: (1) Low PTSD/Mild PTG group (2) Low PTSD/High PTG group; (3) High PTSD/High PTG group. Class membership was predicted by demographic variables, social isolation, and frequency of traumatic experiences. Classes also differed with respect to self-destructive behaviors(binge eating, non-suicidal self-injury, and problem drinking). These findings contribute to future research about the coexisting patterns of PTSD and PTG, and to identify high-risk individuals who suffer from trauma-related problems in clinical practice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1308-1315
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• 2017

This study was conducted to develop Momordica charantia L. juice fermented by four Lactobacillus species such as Lactobacillus paracasei (LPA), Lactobacillus plantarum (LPL), Lactobacillus rhamnosus (LRH), and Lactobacillus reuteri (LRE) as well as to investigate their inhibitory effects against digestive enzymes and antioxidant activities. Fermentation was performed at $37^{\circ}C$ without nutrient supplementation for 72 h. The pH and total lactic acid contents were within the ranges of 3.75~3.96 and 5.21~10.04% in fermented juices, respectively. The type of starter culture and fermentation time induced changes in flavonoid contents more than total phenolic contents. All juices fermented for 48 h strongly inhibited ${\alpha}$-glucosidase activity with the percentage of inhibition ranging of 91.24~95.05%. Antioxidant activities of all juices mostly increased after 48 h of fermentation. Our results suggest that fermented juice possesses inhibitory activity against digestive enzymes and antioxidant activity, and they can be used as health functional beverages.