• The Korean Journal of Financial Management
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• v.23 no.1
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• pp.243-266
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• 2006

This paper tests cross hedging performance of the KOSPI 200 stock index futures to hedge the downside risk of the KOSPI, KOSPI 200 and KOSDAQ50 spot market. For this purpose we introduce the minimum variance hedge model, bivariate GARCH(1,1) and EGARCH(1,1) model as hedge models. The main results are as follows; First, we find that the direct hedge performance of KOSPI 200 index futures is better than those of indirect hedge performance. second, in case or cross hedge performance the hedge effect of KOSPI 200 stock index futures market against KOSPI 200 stock index spot market is relatively better than those of KOSPI 200 index futures against KOSPI and KOSDAQ spot position. Third, for the out-sample, hedging effectiveness of the risk-minimization with constant hedge ratios is higher than those of the time varying bivariate GARCH(1,1) and EGARCH(1,1) model. In conclusion, investors are encouraged to use simple risk-minimization model rather than the time varying hedge models like GARCH and EGARCH model to hedge the position of the Korean stock index cash markets.

• Tuberculosis and Respiratory Diseases
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• v.53 no.4
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• pp.389-400
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• 2002

Background : The rapid diagnostic tests for tuberculosis are needed to facilitate early treatment of tuberculosis and prevention of Mycobacterium tuberculosis transmission. The Xeniss Rapid TB kit is a rapid, card-based immunochromatographic test for the detection of antibodies directed against M. tuberculosis antigens including antigen 5(38-kDa antigen). The objective of this study was to evaluate the performance of the Xeniss Rapid TB kit for the diagnosis of active tuberculosis with serums from patients, asymptomatic healthy and close contact controls. Methods : 188 patients with active tuberculosis were tested; 177 with pulmonary tuberculosis(18 with combined pleurisy), and 11 with extrapulmonary tuberculosis. The control groups were composed of 82 close contacts and 57 healthy adults. Study subject were drawn from one national tuberculosis hospital for patients and close contacts, and another private hospital for healthy adults in Masan city, Korea. The Xeniss Rapid TB kit(Xeniss Life Science Co., Ltd., Seoul, Korea) was evaluated by using serum samples according to the instructions of the manufacturer by an investigator masked to the clinical and microbiological status of the study subjects. Results : The diagnostic sensitivity of the Xeniss Rapid TB kit was 73.9% in patients and specificities were 73.2% and 93.0% in close contact and healthy adults respectively. The positive predictive value in patients was 84.2% and the negative predictive value in controls was 85.8%. Conclusion : This study shows that the Xeniss Rapid TB test is a simple and fast method to diagnose active TB. The results of the sensitivity and specificites suggest that serodiagnosis using this point of care testing(POCT) device would be valuable and advantageous for screening tuberculosis in the clinical field.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.1
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• pp.48-52
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• 2013

Purpose: Bed, living a long time is required in adult patients with brain lesions such as stroke, traumatic brain injury, and Parkinson's disease, causing pneumonia and respiratory diseases may be due to aspiration of food or saliva. In patients with recurrent pneumonia or pulmonary symptoms, there is a need to determine the possibility of pulmonary aspiration due to aspiration of saliva. Materials and Methods: Saliva due to aspiration pneumonia diagnosis in patients with brain lesions request for inspection to the Department of Nuclear Medicine, 10 patients (male 6, female 4) were included in this study. Patients were fasted before the test, $^{99m}Tc_{O4}$ 185 MBq (5 mCi) of less than 1 mL of solution was administered in the oral cavity. Administration and 20 minutes of dynamic imaging acquisition, and immediately after that the static images were acquired. Delayed scan after 2-4 hours if necessary. Results: Positivity rate of all 10 patients was 60%. In 4 patients showed positive reactions after the administration of oral cavity in a 20-minute dynamic imaging were able to confirm whether the aspiration. In the remaining 2 patients, four hours of additional delay tests were able to confirm whether the aspiration. Conclusion: Does not require changes in patient posture compared to the other checks that can be diagnosed with aspiration pneumonia. A simple test and takes less time. Therefore be useful in providing information for the diagnosis and treatment modality.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.3 no.1
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• pp.68-74
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• 2000

Purpose: This study was to investigate the clinical manifestations of FTT in children. Methods: From March 1997 to July 1999, clinical observations were made on patients with FTT who had visited to Samsung Medical Center. Detailed histories and through physical examinations were taken, and when suspected organic FTT, basic laboratory studies were done. Results: Upon the review of medical records, we investigated the clinical manifestations of 74 children, aged 1 month and 13 year 1 month. The causes of FTT were composed of either physiologic (47.8%) or pathologic (52.2%) ones. Among the physiologic FTT, were there familial short stature (FSS, 14.5%), intrauterine growth retardation (IUGR, 14.5%), constitutional growth delay (CGD, 11.6%), idiosyncrasy and prematurity. Among pathologic causes, neurologic disorders (20%) are the most common causes of FTT, and then follow by GI (13.4%), allergic and infectious disorders in decreasing order. The data showed that average caloric intake in patients with FTT was 76,2% of recommended amount. FTT patients with CGD, IUGR, and idiosyncrasy had tendency to take small foods. The FTT children with prematurity, IUGR and pathologic FTT, were short and thin for their ages. However FTT children with CGD and FSS had tendency to be thin with relatively normal heights for their ages, in comparison with those of the children with prematurity, IUGR and pathologic FTT. Conclusion: The diagnosis of FTT was easily obtained with simple and through medical history, physical examination, and minimal laboratory tests. In this study, organic FTT was more prevalent than physiologic one. This results indicate that early intervention is mandatory, because children may develop significant long-term sequelae from nutritional deficiency.

• Korean Journal of Ecology and Environment
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• v.44 no.1
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• pp.31-41
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• 2011

To optimize the natural chemical agents against nuisance phytoplankton, we examined algal removal activity (ABA) of Plant-Mineral Composite (PMC), which already developed by our teams (Kim et al., 2010), on various conditions. The PMC are consisted of extracted-mixtures with indigenous plants (Camellia sinensis, Quercusacutissima and Castanea crenata) and minerals (Loess, Quartz porphyry, and natural zeolite), and characterized by coagulation and floating of low-density suspended solids. A simple extraction process was adopted, such as drying and grinding of raw material, water-extraction by high temperature-sonication and filtering. All tests were performed in 3 L plastic chambers varying conditions; six different concentrations ($0{\sim}1.0\;mL\;L^{-1}$), six light intensities ($8{\sim}1,400\;{\mu}mol\;m^{-2}s^{-1}$), three temperatures ($10{\sim}30^{\circ}C$), four pHs (7~10), five water depths (10~50 cm), and three different waters dominated by cyanobacteria, diatom, and green algae, respectively. Results indicate that the highest ABA of PMC was seen at $0.05\;mL\;L^{-1}$ in treatment concentrations, where showed a reduction of more than 80% of control phytoplankton biomass, while $1,400\;{\mu}mol\;m^{-2}s^{-1}$ in light intensity (>90%), $20{\sim}30^{\circ}C$ temperature (>60%), 7~9 in pH (>90%), below 50 cm in water depth (>90%), and cyanobacterial dominating waters (>80%), respectively. Over the test, ABA of PMC were more obvious on the algal biomass (chlorophyll-${\alpha}$) than suspended solids, suggesting a selectivity of PMC to particle size or natures. These results suggest that PMC agents can play an important role as natural agents to remove the nuisant algal aggregates or seston of eutrophic lake, where occur cyanobacterial bloom in a shallow shore of lake during warm season.

• Journal of Radiation Protection and Research
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• v.39 no.4
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• pp.199-205
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• 2014

In the field of neutron detections, $^3He$ gas, the so-called "the gold standard," is the most widely used material for neutron detections because of its high efficiency in neutron capturing. However, from variable causes since early 2009, $^3He$ is being depleted, which has maintained an upward pressure on its cost. For this reason, the demands for $^3He$ replacements are rising sharply. Research into neutron converting materials, which has not been used well due to a neutron detection efficiency lower than the efficiency of $^3He$, although it can be chosen for use in a neutron detector, has been highlighted again. $^{10}B$, which is one of the $^3He$ replacements, such as $BF_3$, $^6Li$, $^{10}B$, $Gd_2O_2S$, is being researched by various detector development groups owing to a number of advantages such as easy gamma-ray discrimination, non-toxicity, low cost, etc. One of the possible techniques for the detection is an indirect neutron detection method measuring secondary radiation generated by interactions between neutrons and $^{10}B$. Because of the mean free path of alpha particle from interactions that are very short in a solid material, the thickness of $^{10}B$ should be thin. Therefore, to increase the neutron detection efficiency, it is important to make a $^{10}B$ thin film. In this study, we fabricated a $^{10}B$ thin film that is about 60 um in thickness for neutron detection using well-known technology for the manufacturing of a thin electrode for use in lithium ion batteries. In addition, by performing simple physical tests on the conductivity, dispersion, adhesion, and flexibility, we confirmed that the physical characteristics of the fabricated $^{10}B$ thin film are good. Using the fabricated $^{10}B$ thin film, we made a proportional counter for neutron monitoring and measured the neutron pulse height spectrum at a neutron facility at KAERI. Furthermore, we calculated using the Monte Carlo simulation the change of neutron detection efficiency according to the number of thin film layers. In conclusion, we suggest a fabrication method of a $^{10}B$ thin film using the technology used in making a thin electrode of lithium ion batteries and made the $^{10}B$ thin film for neutron detection using suggested method.

• Tuberculosis and Respiratory Diseases
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• v.46 no.4
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• pp.473-480
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• 1999

Background: Early diagnosis of tuberculosis is critical, especially in Korea, an area where tuberculosis is endemic. Because antibody responses to some membrane proteins of Mycobacterium tuberculosis are not comparable, and the policy of BCG vaccination and the prevalence of tuberculosis are different from country to country, the usefulness of the serological diagnostic tests is questionable in Korea, even though they have been confirmed to be useful in other countries. In the specific context of Korea, we tried to evaluate the validity of the ICT Tuberculosis Test (ICT), a membrane-based antibody kit that purports to detect the 5 M. tuberculosis complex-specific antigens including 38-kDa protein. Method: 68 patients with tuberculosis were tested : 37 had no history of previous tuberculosis, and 31 were reactivated cases. The control group comprised 77 subjects : 25 healthy adults, 35 hospital workers with frequent contact with tuberculosis patients, and 17 in-patients with non-tuberculous respiratory diseases. Results: The diagnostic sensitivities of the ICT were 87% and 73% in patients with versus without previous history of tuberculosis, respectively. The sensitivities of smear-positive and smear-negative patient groups were 81% and 73%, respectively. Both of the two patients with extrapulmonary tuberculosis tested positive through the ICT. The specificities of the ICT were 88%, 94%, and 94% in healthy adults, hospital workers, and non-tuberculous patients, respectively, with an overall specificity of 92%. Conclusion: It is suggested that when combined with traditional techniques, the ICT is an useful tool for the diagnosis of pulmonary tuberculosis. The procedure is simple, easy to perform, rapid, and needs no equipment. It shows 73% sensitivity and 92% specificity for the diagnosis of tuberculosis.

• Tuberculosis and Respiratory Diseases
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• v.48 no.4
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• pp.438-447
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• 2000

Background : Transbronchial lung biopsy (TBLB) is a relatively simple and convenient procedure to obtain lung tissue from a patient with diffuse or localized lesion on chest radiographs, whose disease cannot be diagnosed through routine tests. The authors tried to evaluate the diagnostic value of TBLB, especially, the concordance between CT scan and TBLB with respect to the location of the lesion and diagnostic yield according to tumor-bronchus relationship. Method : We reviewed the medical records, plain chest films, and chest CT scans of 278 patients who underwent TBLB at Kyungpook National University Hospital between January 1996 and June 1998. Results : One hundred and sixteen (41.7 %) patients were diagnosed by TBLB. Diagnostic yield of TBLB of malignant tumors tended to be higher than that of benign diseases (64.7% versus 53.9%, p=0.09). Of primary lung cancers, TBLB was more diagnostic in adenocarcinoma and small-cell carcinoma than other cell types (p<0.01) and, of benign diseases, more diagnostic in tuberculosis than in non-tuberculous diseases (p<0.05). There was no significant difference in the diagnostic rate according to the location of the tumor. The diagnostic rate tended to increase with the size of tumor (p=0.06). The diagnootic rate of TBLB did not differ according to the pattern of lesion in benign diseases. However, in malignant diseases TBLB was more diagnostic in diffuse/multiple nodular lesions than in localized lesions(p<0.05). According to the tumor-bronchus relationship, TBLB was more diagnootic in type I/II groups than in other types. CT scan and TBLB showed a strong correlation with respect to the localization of the lesion (r=0.994, p<0.01). Conclusion : The above results show that TBLB is useful in the diagnosis of lung disease. CT scan and TBLB showed a strong correlation in determining the location of the lesion. Diagnostic yield of TBLB is higher in lesions with 'bronchus sign' (type I and II). TBLB and other diagnootic methods such as transthoracic needle aspiration are expected to complement one another in the diagnosis of lung diseases.

• Korean Journal of Plant Resources
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• v.27 no.4
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• pp.380-391
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• 2014

Plants as well as crops are damaged by a combination of the hot and dry winds that has been a major factor in the reduction of crop production. A means to protect them from damaging conditions is to consider a coating material. In this study, we established laboratory screening methods to find a coating material to protect a crop from rapid transpiration caused by various factors. In a test measuring the weight loss of kidney bean seedlings for 6 days, Avion treatments decreased its weight loss (P=0.05). Owing to long-time spend in completing this assay, we performed a more simple method using a cobalt chloride paper strip, which changes from blue to red colors under water condition. Beewax, guagum, paraffin liquid, soybean oil, and PE-635 gave a waterproofing effect above 37 and 43% at 0.5 and 1 h after treatment, respectively. However, these tested materials did not show significant waterproofing results at 2 h. Although the methods produced reasonable results, a screening method to obtain more objective data is needed. An alternative is to use an instrument that can detect the transpiration of crop leaves. In a preliminary test using barley leaves, a portable photosynthesis system showed transpiration inhibition of 2% soybean oil and 10 times-diluted Avion under field conditions. In another test using the leaves of maize seedlings and apricot tree, 2% liquid paraffin and plant oils such as apricot oil, linseed oil, olive oil, and soybean oil showed significant transpiration inhibition (P=0.05). Especially, paraffin liquid and soybean oil selected from above tests gave good transpiration inhibitory effects against rice at 2%. In addition, the mixture of 2% soybean oil and a spreader showed more elevated inhibition results comparing with soybean oil or the spreader alone indicating that the spreader may be attributed to more uniform diffusion of the hydrophobic material onto the leaf surface of maize seedlings. The hydrophobic material coated physically the stomata and cuticle layers on leaf surfaces of rice. These hydrophobic materials screened in this study are expected to be used as plant coating materials.

• The Journal of Korean Academy of Sensory Integration
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• v.15 no.2
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• pp.46-65
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• 2017

Objective : The purpose of this research is to find clinical effects of application of weighted vest during task-oriented training focused on gross motor performance and balance abilities of children with spastic diplegia. Methods : 34 subjects were divided by simple random sampling into two groups; experimental group (male : 9, female : 8, average age : 8.12) and placebo group (male : 9, female : 9, average age : 7.53). Both two groups underwent to 40 minute intervention, twice a week for 12 weeks. The intervention was task-oriented training focused on facilitating closed kinematic chain and multi-joint functional movement pattern. During the training, the experimental group received loaded-resistance weighted vest and placebo group also received weighted vest but without loaded-resistance. Participants in both groups underwent 8 to 10 reps of the task-oriented training and there were 3 minutes break time between tasks. There were pre-test of gross motor performance and balance abilities, and two times of post-tests were performed upon 6 weeks and 12 weeks after the intervention completed. And in final, an additional follow-up test was performed 12 weeks after the evaluation was finished in order to find any difference between the two groups over time. Results : There was significant difference in Gross Motor Performance Measure (GMPM) between two groups. It is found that average score of the experimental group increased more than the placebo group after 6 weeks and 12 weeks intervention (p<.05). There was significant difference in Pediatric Berg's Balance Scale (PBS) between two groups. It is found that average score of the experimental group increased more than the placebo group after 6 weeks and 12 weeks intervention (p<.05). Conclusion : Based on the results in this study, it is proposed that application of weighted vest into task-oriented training to facilitating closed kinematic chain and multi-joint movement can improve gross motor performance and balance abilities of children with cerebral palsy.