• Journal of Construction Engineering and Project Management
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• v.1 no.3
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• pp.28-37
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• 2011

Domestic construction companies are suffering from financing difficulties in the wake of the economic slump in Korea and abroad. During this economic slump, real estate investment trusts (REITs), facilitators for improving financing and stimulating construction businesses, have increasingly expanded since their introduction in 2001. However, in terms of growth speed and marketing size, Korean REITs are falling behind those of other nations. The purpose of this study is to suggest a method for composing a portfolio using the Markowitz portfolio selection model to stimulate REITs. The main contents are as follows. First, a comparative analysis was conducted of increased REIT profit with the application of the Markowitz model and the average REIT profit rate from July 3, 2007, to July 21, 2008, during the investment analysis periods. The results showed that the total profit rate from the Markowitz model was about 10% higher than the average REIT profit rate. Second, the sensitivity was analyzed according to the portfolio's data-gathering and replacement cycle to measure the optimum cycle and yield. The six-mouth profit data collection period showed about 16% higher profits with the Markowitz model than with the REITs. The two-week portfolio change period resulted in about 11% higher profits with the Markowitz model than with the REITs.

• The Korean Journal of Financial Management
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• v.25 no.2
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• pp.165-190
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• 2008

The degree of informational asymmetry relating to the expiration of index derivatives is usually increased as an expiration day of index derivatives approaches. The increase in the degree of informational asymmetry may have some effects on trading behavior of investors. To examine what the effects look like, 'life cycle of index derivatives' in this study is defined as three adjacent periods around expiration day: pre-expiration period(a week before the expiration day), post-expiration period(a week after the expiration day), and remaining period. It is inspected whether stock investor's trading behavior is changed according to the life cycle of KOSPI200 derivatives and what the reason of the changing behavior is. We have four results. First, trading behavior of each investor group is categorized into three patterns: ㄱ-pattern, L-pattern and U-pattern. The level of trading activity is low for pre-expiration period and normal for other periods in the ㄱ-pattern. L-pattern means that the level of trading activity is high for post-expiration period and normal for other periods. In the U-pattern, the trading activity is reduced for remaining period compared to other periods. Second, individual investors have ㄱ-pattern of trading large stocks according to the life cycle of KOSPI200 index futures while they show U-pattern according to the life cycle of KOSPI200 index options. Their trading behavior is consistent with the prediction of Foster and Viswanathan(1990)'s model for strategic liquidity investors. Third, trading pattern of foreign investors in relation to life cycle of index derivatives is partially explained by the model, but trading pattern of institutional investors has nothing to do with the predictions of the model.

• Asia Marketing Journal
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• v.11 no.4
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• pp.21-48
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• 2010

This article analyzes film performances in the Korean movie market utilizing three-stage models that incorporate available information in three different stages of the movie life cycle, i.e., at the time of its release, at the end of the first week, and at the end of its life cycle. Based on the premise that the performance of a movie is affected principally by factors of scale, evaluation, and competition, we attempted to ascertain the effects on these factors on performances, and how they differ in different stages. Also, by analyzing domestic and foreign movies released in Korea separately, we were able to compare the different effects of the three factors on the performances of the two categories of movies. Additionally, our movie performance models incorporated herding behavior among the customers. Our results demonstrate that herding is prominently observed after the first week only for domestic movies. In general, the scale factor has been shown to be most important for movie performances in all stages. For foreign films, it is particularly critical for the first week and total performances. Whereas the evaluation factor influences domestic film performance more strongly at the screen choice stage, it affects the performance of foreign films more strongly in the later stages of the life cycle. As compared to foreign films, domestic film performance appears to be more sensitive to the competition factor. We also discuss the effects of covariates such as genre and symbolicity on movie performance.

• Women's Health Nursing
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• v.22 no.1
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• pp.61-70
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• 2016

Purpose: This study is an explorative survey to examine emotional labor, stress, and premenstrual syndrome among hospital nurses and to examine relationships among them. Methods: Data were collected from 228 nurses working at hospitals using structured questionnaires from September to October, 2014. Data were analyzed using SPSS 21.0 by frequency, descriptive statistics, t-test, one-way ANOVA, and Pearson's correlation coefficient. Results: Score of emotional labor was different by work time per week (F=4.03, p=.019), and menstrual amount (F=5.18, p=.006). Level of stress was different by marital status (t=2.29, p=.023), pattern of work (t=-3.63, p<.001), work time per week (F=3.39, p=.035), regularity of menstrual cycle (t=-4.20, p<.001), and exercise frequency (F=4.28, p=.015). Scores of premenstrual syndrome were different by regularity of menstrual cycle (t=-3.18, p=.002), and menstrual amount (F=5.88, p=.003). Emotional labor was related with perceived stress (r=.40, p<.001) and premenstrual syndrome (r=.23, p<.001). Also, perceived stress was related with premenstrual syndrome (r=.33, p<.001). Conclusion: Nurses' emotional labor, stress, and premenstrual syndrome were higher than the average. Emotional labor was correlated with stress and premenstrual syndrome, premenstrual syndrome with stress. This study shows that it is necessary to understand these relationships and to search for nursing intervention to ease emotional labor, stress, and premenstrual syndrome.

• Journal of Veterinary Clinics
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• v.33 no.6
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• pp.395-399
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• 2016

In the present case, the effect and toxicity of carboplatin and cyclophosphamide chemotherapy combined with surgery of mammary tumors in a dog were examined. An 8-year old spayed female Beagle presented with a mammary tumor. Physical examination, radiography, ultrasonography, computed tomography (CT), and laboratory examination were performed. Metastasis of the mammary tumor was confirmed by CT scan. Chemotherapy using a combination of carboplatin and cyclophosphamide was initiated following surgery. The first cycle of chemotherapy was planned to last for 6 weeks; it was planned that carboplatin would be intravenously administered for the first week (1 day) and cyclophosphamide would be intravenously administered for the next 3 weeks (22 days). Between the end of cycle 1 and the beginning of cycle 2, based on CT, it was confirmed that the number and size of tumors were unchanged and the tumors had not spread to other organs. However, at the end of cycle 2 and the beginning of cycle 3, CT revealed an increase in the number and size of mass in the lung. Chemotherapy was associated with adverse effects such as lethargy, anorexia, leukopenia, and hair loss. In conclusion, this case showed that a combination of carboplatin and cyclophosphamide suppressed the development of new neoplasms as well as metastasis for a certain period of time but did not improve the survival time. Although more cases are required, this chemotherapeutic procedure remains challenging.

• Journal of International Academy of Physical Therapy Research
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• v.5 no.2
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• pp.708-713
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• 2014

The aim of this research was to investigate how the effects of body supported treadmill training with visual feedback affect the gait factors of stroke patients. Thirty subjects (21 male, 9 female) with a diagnosis of stroke were taken to the hospital to participate in this study. The subjects received body supported treadmill training with visual feedback. The training was executed for 6 minutes, 3 times a day per week for 19 weeks after general exercise. The effects of the visual feedback in the body supported treadmill training were evaluated by measuring the average gait cycle and the average step length of the affected and unaffected. The collected data were statistically analyzed by using a paired t-test. The results of this study were a significant improvement of the average gait cycle and no statistically significant difference of the average step length. The gait cycle average had a statistically significant difference in gender, age, etiology, paretic side, and step length average. There was no statistically significant difference in infarction within etiology. Therefore, it was necessary to apply the easy and simple with the treadmill training in the rehabilitation of the stroke patients. This study will require a variety of outcome measures related to the effects of treadmill training with gait factors.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.2.1-2.15
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• 2023

Background: Phthalates are endocrine disrupting chemicals that are widely used in the production of items of daily life such as in polyvinylchloride plastics, insecticides, and medical devices. This study aimed to determine the association between phthalate exposure and shellfish consumption using data from the Korean National Environmental Health Survey (KoNEHS) cycle 3 (2015-2017), which is a nationally representative survey. Methods: In this study, we analyzed the KoNEHS cycle 3 data of 3,333 (1,526 men and 1,807 women) adults aged more than 19 years. Data related to the variables of sociodemographic factors, health-related behaviors, dietary factors, seafood consumption frequency, and urinary phthalate metabolites concentrations were collected. The concentrations of urinary phthalate metabolites of all the participants were divided into quartiles to define high and low concentration groups based on the 75th percentile concentration. A χ² test was conducted to analyze the distribution of independent variables. To analyze the relationship between shellfish consumption and phthalate exposure, the odds ratios (ORs) were calculated using logistic regression analysis. Results: Total adults with shellfish consumption frequency of over once a week showed the following adjusted ORs for high concentrations of the following metabolites compared with the group that consumed shellfish once a week or less: 1.43 (95% confidence interval [CI]: 1.01-2.06) for mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP), 1.43 (95% CI: 1.01-2.03) for mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), 1.57 (95% CI: 1.10-2.24) for ∑di-2-ethylhexyl phthalate (∑DEHP), 2.01 (95% CI: 1.46-2.77) for mono-carboxyoctyl phthalate (MCOP), 1.56 (95% CI: 1.11-2.18) for mono-carboxy-isononly phthalate (MCNP), and 2.57 (95% CI: 1.85-3.56) for mono (3-carboxypropyl) phthalate (MCPP). Conclusions: The concentrations of urinary phthalate metabolites (MEOHP, MECPP, ∑DEHP, MCOP, MCNP, and MCPP) were higher in adults with a higher frequency of shellfish consumption.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.3
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• pp.483-490
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• 1999

Objectives: Polycystic ovary syndrome (PCOS) has the feature of excessive LH, hyperandrogenism and disturbance of folliculogenesis. Also, insulin, IGF-I and IGFBP-l are involved in the pathogenesis of PCOS. Various surgical and medical therapies have been used and the action mechanisms are related to the endocrine effect. Laparoscopic ovarian electrocautery or laser vaporization is effective in the restoration of ovulation and normal menstrual cycle with minimal invasive procedure especially in the patients resistant to medical therapy. Clomiphen citrate (CC) is used for the ovulation induction in pcas and the resistance is known to be related to insulin, IGF-I, IGFBP-l levels. This study was performed to evaluate the effect of the laparoscopic laser vaporization on the levels of LH, FSH, testosterone, IGF-I and IGFBP-l and on the ovarian response to clomiphen citrate in patients with CC-resistant PCOS. Materials and Methods: The fasting basal serum LH, FSH, testosterone, IGF-I and IGFBP-l level were measured in 10 PCOS patients with CC-resistance and 7 normal controls with regular menstrual cycle. In PCOS, after laparoscopic $CO_2$ laser vaporization, endocrine levels were measured in 1 week interval for 4 weeks and then compared with preoperative levels. Results: In PCOS group, mean serum LH/FSH ratio, testosterone, IGF-I levels were higher and IGFBP-l level was lower than control. LH/FSH ratio decreased from $2.51{\pm}0.67$ to $1.7{\pm}0.6$ (p<0.05) in 2 weeks, to $0.56{\pm}0.2$ (p<0.01) in 3 weeks and to $1.41{\pm}0.3$ (p<0.01) in 4 weeks after operation. Testosterone level decreased from $1.51{\pm}0.82ng/ml$ to $0.65{\pm}0.34ng/ml$ (p<0.05) in 2 weeks, to $0.56{\pm}0.67ng/ml $(p<0.01) in 3 weeks after operation. IGF-I level also decreased from $436{\pm}47.5{\mu}g/l$ to $187{\pm}38{\mu}g/l$ (p<0.0l) in 1 week, to $167{\pm}42{\mu}g/l$ (p<0.01) in 2 weeks, $179{\pm}55{\mu}g/l$ (p<0.01) in 3 weeks and to $120{\pm}43{\mu}g/l$ (p<0.01) in 4 weeks after operation. IGFBP-l level showed no significant change. In 8 of 10 PCOS patients, ovulation was induced with low dose clomiphen citrate. Conclusion: Laparoscopic $CO_2$ laser vaporization restores normal menstrual cycle and ovulation through endocrine effect of decreasing LH/FSH ratio, testosterone and IGF-I level and increases the response to CC. Therefore it is useful for restoration of normal menstruation and induction of ovulation in CC resistant PCOS patients.

• Journal of Embryo Transfer
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• v.32 no.3
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• pp.177-182
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• 2017

This study was conducted to investigate the ovarian cycle changes of the mare according to the season. Twenty four Jeju crossbred horses(Thoroughbred ${\times}$ Jeju horse) raised in Subtropical Livestock Research Institute, National Institute of Animal Science, RDA were used to identify follicles and corpus luteum with ultrasonography once a week(May 2016~June 2017). Blood samples of experimental horses were collected twice a week for analysis of P4 hormone levels. The mares were considered to have resumed ovarian cyclicity on the day of ovulation if they followed by regular ovarian cycles. Only 13 cases(61.9%) of the total 21cases showed normal ovarian cycle, and 8 cases (38.1%) showed delayed ovarian cycle. Three cases(16.7%) in October, 5 cases(27.8%) in November and 5 cases(27.8%) in December(27.8%) ceased the heat and the remaining 5 cases(27.8%) showed that the estrus was maintained in winter. Horses that stopped estrus ceased the heat until March of next year, and 27.8% were continued the heat during non-breeding season. Eleven cases(61.1%) of 18 cases in April and 2 cases(11.1%) of 18 cases in May returned the estrus.

• Radiation Oncology Journal
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• v.19 no.2
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• pp.146-152
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• 2001

Purpose : To investigate the regulation of apoptosis and cell cycle in mouse brain irradiation. Materials and Methods : 8-week old male mice, C57B1/6J were given whole body $\gamma-radiation$ with a single dose of 25 Gy using Cobalt 60 irradiator. At different times 1, 2, 4, 8 and 24hr after irradiation, mice were killed and brain tissues were collected. Apoptotic cells were scored by TUNEL assay. Expression of p53, Bcl-2, and Bax and cell cycle regulating molecules; cyclins Bl, Dl, E and cdk2, cdk4, $p34^{cdc2}$ were analysed by Western blotting. Cell cycle was analysed by Flow cytometry. Results : The peak of radiation induced apoptosis is shown at 8 hour after radiation. With a single 25 Gy irradiation, the peak of apoptotic index in C57B1/6J is $24.0{\pm}0.25$ (p<0.05) at 8 hour after radiation. Radiation upregulated the expression of p53/tubulin, Bax/tubulin, and Bcl-2/tubulin with 1.3, 1.1 and 1.45 fold increase, respectively were shown at the peak level at 8 hour after radiation. The levels of cell cycle regulating molecules after radiation are not changed significantly except cyclin D1 with 1.3 fold increase. Fractions of Go-Gl, G2-M and S phase in the cell cycle does not specific changes by time. Conclusion : In mouse brain tissue, radiation induced apoptosis is particularly shown in a specific area, subependyma. These results and lack of radiation induced changes in cell cycle ofter better understanding of radiation response of noraml brain tissue.