• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.99-106
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• 1998

Background: Bronchial asthma is a complex disease, which is characterized by spontaneous exacerbations of airway obstruction and persistent bronchial hyperresponsiveness. Animal models have fallen short of reproducing the human disease, particularly in mimicking the spontaneous and persistent airflow obstruction that characterized in asthma. In animals, airflow obstruction is usually assessed by measuring airflow resistance during tidal breathing under such invasive technique as tracheostomy and anesthesia. A noninvasive technique for measuring pulmonary function in small animals is needed to evaluate long-term changes in lung function during the course of experimentally produced disease without sacrificing the animal. Purpose: The purpose of this study was to evaluate early bronchoconstrcition after allergen challenge and airway responsiveness (AR) to inhaled methacholine in nonanethetized, unrestrained guinea pigs. Method: Guinea pig model of asthma was sensitized by subcutaneous injection with ovalbumin and challenged by inhalation of aerosolized ovalbumin(1% wt/vol ovlabumin). Airflow obstruction of conscious guinea pig was measured as specific airway resistance (airway resistance $\times$ thoracic gas volume). Airway resistance and thoracic gas volume of conscious guinea pig were assessed by body plethysmography before challenge and at regular intervals for as long as 30 minutes after challenge. AR to aerosolized methacholine of asthma group was compared with that of control group in body plethysmography. Result: Asthma model<> developed in 13 (65%) among 20 guinea pigs, in which early responses occurred in the airways after the exposure to inhalation with ovalbumin. Airway challenge with ovalbumin caused increase in specific airway resistance, which peaked at 6 minutes and amounted to a $231.5{\pm}30.4%$ increase from baseline. AR to aerosolized methacholine of asthma model increased significantly compared with control group. Conclusion: These results have showed a useful animal model to evaluate early bronchoconstrcition after allergen challenge and airway responsiveness in nonanethetized, unrestrained guinea pigs.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.6
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• pp.1137.2-1245
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• 2001

The ${\gamma}$-irradiated medicinal herbs were examined the genotoxicological safety to consider the possibility of application of the irradiation technology for hygienic purpose. The three medicinal herbs -Glycyrrhigae Radix, Aurantii nobilis Pericarpium and Bupleuri Radix- were irradiated with ${\gamma}$ -rays at the practical dosage of 10 kGy. The hot water extracts of the irradiated herbs were examined in two short-term in vitro tests: (1) Ames test in Salmonella typhimurium TA98 and TA100, (2) Micronucleus test in cultured Chinese hamster ovary(CHO) cells. In the Salmonella reversion assays both with and without metabolic activation, the number of revertant colonies was not increased with each extract from the irradiated herbs, compared with negative controls. No significant difference in formation of the colonies was observed between non-irradiated and 10 kGy-irradiated herbs. These results indicated that no mutagenicity of the irradiated herbs was detected. In the micronucleus tests in cultured CHO cells, the incidences of micronucleus were not increased with irradiated herbs, and no significant difference in the incidences was observed between non-irradiated and irradiated herbs. These results indicated that no cytogenetic toxicity of the irradiated herbs was detected. The results of the two in vitro tests suggest that the irradiated herbs do not show mutagenic effects and cytogenetic toxicity. Further tests of in vivo genotoxicity and chronic toxicity are needed to determine the safety of the herbs irradiated with ${\gamma}$ -rays at practical doses.

• Journal of Korean Society of Forest Science
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• v.95 no.6
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• pp.680-689
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• 2006

Introduction of the Special Account for Balanced National Development (SABND) which was represented top-down in 2005 have previous national budget distribution system between central and local government change. A local autonomous entities can choose freely the favorite programs within the total programs in SABND so they can use limited budget efficiently, After induction of this system, budget of the Forest Programs in SABND in 2006 compare to last year has increased by 24.5 percent. That is three times higher than the average rate of total SABND budget, 8.1 percent. This study surveyed propriety of the Forest Programs and hereafter their budget prospect with local government officials in forest sector, 68.7 percent of the respondents recognized that the inclusion of the Forest Programs in SABND is proper. The most preferred Forest Programs are making Urban Forests and their Management and making Facilities for Forest Recreation. And the most non-preferred Forest Programs are complementing the Lumberyard Facility of the Forestry Association, making the Exhibition of Wood Products and making the Base for the Seedling Production. When Forest Programs are adjusted in the future, these programs above mentioned should be exempted from the SABND. because the non-preferred programs as well as the small budget programs On the prospect of the future budget, 81.1 percent of the local government officials in forest sector answered that it will be the same with the current or increasing, In the short term, the budget of the Forest Program in SABND is expected to increase.

• Journal of the Korean Institute of Gas
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• v.24 no.2
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• pp.1-8
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• 2020

Centrifugal pump is a facility that transfers energy to fluid through centrifugal force, which is usually generated by rotating the impeller at high speed, and is a major process facility used in many LNG production bases such as vaporization seawater pump, industrial water and fire extinguishing pump using seawater. to be. Currently, pumps in LNG plant sites are subject to operating conditions that vary depending on the amount of supply desired by the customer for a long period of time. Pumps in particular occupy a large part of the consumption strategy at the plant site, and if the optimum operation condition is not available, it can incur enormous energy loss in long term plant operation. In order to solve this problem, it is necessary to identify the performance deterioration factor through the flow analysis and the result analysis according to the fluctuations of the pump's operating conditions and to determine the optimal operation efficiency. In order to evaluate operation efficiency through experimental techniques, considerable time and cost are incurred, such as on-site operating conditions and manufacturing of experimental equipment. If the performance of the pump is not suitable for the site, and the performance of the pump needs to be reduced, a method of changing the rotation speed or using a special liquid containing high viscosity or solids is used. Especially, in order to prevent disruptions in the operation of LNG production bases, a technology is required to satisfy the required performance conditions by processing the existing impeller of the pump within a short time. Therefore, in this study, the rotation difference of the pump was applied to the ANSYS CFX program by applying the modified 3D modeling shape. In addition, the results obtained from the flow analysis and the curve fitting toolbox of the MATLAB program were analyzed numerically to verify the outer diameter correction theory.

• KDI Journal of Economic Policy
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• v.30 no.2
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• pp.157-183
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• 2008

'New Universities for Regional Innovation(NURI)' is a financial aid program designed to promote the development of universities as a major component of Regional Innovation System (RIS). In particular, this program emphasizes the role of regional universities to provide the qualified graduates for the regional economy. This paper is to evaluate the effect of NURI, focusing on the change of graduates' employment. The effect of the program can be evaluated by the quality of graduates' accumulated human capital, and graduates' employment performance represents the graduates' quality evaluated in the labor market. This is also believed to be a good performance indicator of the NURI program. We utilize the graduate employment survey of Korean Educational Development Institute (KEDI), and calculate the graduates' employment rates of the departments that received the financial support of NURI (treatment group). We also calculate the graduates' employment rates of the departments that applied for the support of the NURI program but were not selected (comparison group). By using difference-in-differences method, we compare the change of graduates' employment rates in treatment and comparison groups before and after the program came in effect. Compared with the employment rates in 2004 before the NURI program started, the graduates employment rates improved in both groups in 2005 and 2006. The improvement of the employment rates in the treatment group is larger than that in the comparison group. Moreover, the difference of improvement gets larger in the year 2006 than in 2005, which means those students who were affected more years by the NURI program are more likely to be employed. However, the difference is not statistically significant, and we cannot definetely conclude that NURI showed the desired effect on the quality of the college graduates. We calculate employment rates in two ways; whether to treat going on to graduate education as an employment or not. The result was qualitatively the same in both cases. We also tracked quality of employment by investigating the firm size where the graduates of the treatment group were employed. By utilizing data from the Employment Insurance Fund, we measure the firm size by the number of employees. We did not find any deterioration of employment quality between 2005 and 2006, though it deteriorates in 2007. Therefore, the improvement of employment rates until 2006, though not statistically significant, does not seem to come at the cost of employment quality. The interpretation of this result cannot help being very limited. First, this evaluation covers such a short time period. It only covers two years after the program started, 2005 and 2006. Second, the extent of the improvement in employment rates is not satisfactory considering the amount of financial support, even though it can be argued that the employment has improved since the inception of the program. Subsequent evaluation of the program is required to certify the NURI programs' longer term effectiveness.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.326-332
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• 2011

The growth and bolting characteristics of spring Chinese cabbage cultivars at two night-time temperature treatments such as $5^{\circ}C$ and $10^{\circ}C$ during seedling stage were investigated to establish a safe environmental management strategy for raising seedlings. The low night-time temperature treatments were applied at 5, 10, and 15 days after sawing and the treatment durations were 5, 10, and 15 days in each of treatment beginning. The growth of seedlings in all the tested cultivars were linearly reduced as the treatment duration was extended and no symptoms of bolting were found. The reduction rate in seedling growth of 'Chunkwang' reached to 59.3% at most by 15 days of $5^{\circ}C$ treatment when it be compared to that of control. However, no symptoms of bolting were shown in the treatments of two night-time temperatures until the harvest at 90 days after sawing, indicating that the vernalization effect by low night-time temperature could be mitigated by subsequent day-time optimal temperature management. This study showed that the major spring Chinese cabbage cultivars require more ultimate level of low night-time temperature treatment for the vernalization than this study. It is also supposed that the optimal day-time temperature management can reduce or delay the rate of bolting, even if the seedlings were exposed to short-term low temperature below $5^{\circ}C$ during night-time.

• Journal of Ginseng Research
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• v.33 no.2
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• pp.115-126
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• 2009

To evaluate the efficacy and safety of red ginseng on women's health-related quality of life (QOL) and sexual function. A randomized, double-blind, placebo-controlled, crossover clinical study was performed. The main efficacy was measured using the Female Sexual Function Index (FSFl) and the 36-Item Short-Form Health Survey (SF-36). Twenty-four healthy, married women aged 30-45 years with FSFl scores below 25 were randomly divided into two groups: the red-ginseng group (N=12) and the placebo group (N=12). During the first six-week period (Study 1), each group was given red ginseng or placebo twice a day. Before the start of the second six-week period (Study 2), a crossover design was chosen with a two-week break (washout period). Interchanging the two groups after the washout period, red ginseng and placebo were given to each group. The outcomes were measured before and after each six-week period. Overall, 23 participants completed the study. In Study 1, the changes relative to the baseline in the FSFl total score were 22.50% and 22.99% for red ginseng and placebo, respectively. In Study 2, the relative changes were 8.14% for red ginseng and 6.29% for placebo. The results showed a greater improving trend in Study 1 with respect to all of the participants' sexual functions, but no significant difference was found between the groups (P=0.9567). After taking red ginseng, all the participants exhibited an improving trend in the desire domain of FSFl, but no significant difference was shown. In the measurement of SF-36, no significant difference was likewise shown. After taking red ginseng, though, all the participants exhibited an improving trend in the physical functioning (PF) domain of SF-36, with no significant difference. Moreover, there was no significant adverse event related to red ginseng. The QOL and sexual function of the study participants in the red-ginseng group were mostly improved, but no statistically significant effect of red ginseng was shown. It is supposed that this result was partly due to the affirmative impression of red ginseng in Korea. Thus, it is anticipated that a long-term clinical trial will show a significant effect of red ginseng on the QOL and sexual function.

• Clinical and Experimental Reproductive Medicine
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• v.37 no.1
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• pp.13-23
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• 2010

Objective: The present study was carried out to induce differentiation of human embryonic stem cells (hESCs) into germ cells and to establish a culture condition for single hESCs dissociated by enzyme. Methods: Embryonic body (EB) was formed by hanging drop culture for 3 days from hESCs colony. The EBs were cultured in the medium supplemented with retionic acid (RA) or/and bone morphogenetic protein-4 (BMP4) for 14 days to differentiate into germ cells. Germ cell specific markers, c-kit and VASA were used for immunohistochemistry of EB. Human ESCs colonies were dissociated into single cells by Collagenase, Tryple and Accutase, and then colony formation rate of the single cells was examined. Rho-associated kinase inhibitor (ROCK inhibitor, Y27632) was added into the culture medium of single cells to reduce the apoptotic damage during the dissociation. Results: Single cells dissociated with Tryple or Accutase showed higher colony formation rates compared to the cells dissociated with Collagenase. Seeding of $5{\times}10^3$ cells/well (4 well dish) was efficient to obtain high colony formation rate compared to other concentrations of seeding cell. Addition of Y27632 significantly increased the colony formation rate of the single cells dissociated by Tryple. Immunohistochemistry of EB with c-kit and VASA markers showed a weak fluorescence signals compared to the signals from the testicular tissue. Conclusion: Dissociation with Tryple was useful to obtain healthy single cells and addition of Y27632 was beneficial for survival and colony formation of the single cells. Unlike other studies, we just observed a dim fluorescence staining of the germ cell markers, probably caused by the short-term culture for the differentiation of EB compared to other studies.

• Journal of agricultural medicine and community health
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• v.29 no.2
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• pp.303-314
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• 2004

Objectives: This study was carried out to assess exposure levels of organic dusts and ammonia in poultry farms in Korea. Methods: A total of six poultry farms were investigated. The farms were located in Namwon, Chonlabuk-do and in Kae-San, Chungchongbuk-do. This study consisted of a questionnaire and measuring organic dusts and ammonia. The questionnaire included the characteristics of the farms, work patterns and the tasks of the poultry farms. Results and Conclusions: The farmers raised the chickens 45 times a year and the average number of years in the poultry farm were eight years ranging from 2 to 12 years. They worked for seven days per week and the average hours spent caring the chickens are 6.3 hours per day. The duration of staying in the confinement buildings was 3.3 hours per day. The work time in summer was longest. The feed and the water supply systems were automatic and the control of ventilation windows used "winch curtain" was semiautomatic. They used mechanical ventilation system in winter and used dilution ventilation system in the other seasons. The geometric mean concentration of total and respirable dust sampled in the poultry confinement buildings was 4.0 mg/$m^3$and 0.9 mg/$m^3$ respectively. The ratio of respirable to total dusts range from 9 to 49 percent. There was no sample exceeding the criteria 10 mg/$m^3$ for total dust and 3 mg/$m^3$ for respirable dust in farms. The criteria have been recommended by Korean Ministry of Labor and American Conference of Governmental Industrial Hygienist. The personal respirable dusts measured during a circle work averaged geometric mean concentration 1.4 mg/$m^3$ Two personal samples were exceeded the threshold 3 mg/$m^3$. There was a positive relation between an index and the personal samples of respirable dusts($R^2$=0.98). The index is calculated by multipling the total number of chickens in the farm by the age of the chickens and then dividing by the volume of the confinement building. The geometric mean concentration of area and personal ammonia samples was 23.3 ppm and 22.2 ppm, respectively. Some of the ammonia samples, both area and personal samples, exceeded the short term exposure limit value 35 ppm.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.3 no.1
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• pp.26-45
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• 1992

This study presents the behavioral and cognitive changes by administration of methylphenidate(MPH) and imipramine(IMI) for the treatment of attention-deficit hyperactivity disorder(ADHD) in $5_{1/2}{\sim}12$ years old children referred to child psychiatric clinics. Behavioral changes are assessed with parent's and teacher's ratings. Drug effects on attention. short-term memory, and impulsivity are evaluated with psychological tests in laboratory. The changes were assessed twice in a 8-week periods. The data were analyzed seperately for 15 subjects each drug using repeated measured analysis of variance(ANOVA). The findings indicates that behavioral and cognitive impairments are improved by both drugs, but impulsivity is not. And MPH is superior to IMI on the improvement of attentional problem ; especially the findings indicates important differences between simple task and complex. perceptual-search task. These data confirm the effectiveness of MPH for treatment of ADHD, also raise questions regarding assessment method of attention and impulsivity as fell as importance of impulsivity in ADHD.