• Journal of Radiation Protection and Research
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• v.38 no.4
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• pp.214-227
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• 2013

Computed tomographic scan as a screening procedures in asymptomatic individuals has seen a steady increase with the introduction of multiple-raw detector CT scanners. This report provides a brief review of the current controversy surrounding CT cancer screening, with a focus on the radiation induced cancer risks and clinical efficacy. 1. A large study of patients at high risk of lung cancer(the National Lung Screening Trial[NLST]) showed that CT screening reduced cancer deaths by 20%(1.33% in those screened compared with 1.67% in those not screened). The rate of positive screening tests was 24.2% and 96.4% of the positive screening results in the low-dose CT group were false-positive. Radiation induced lung cancer risk was estimated the most important in screening population because ERR of radiation induced lung cancer does not show the decrease with increasing age and synergistic connection between smoking and radiation risk. Therefore, the radiation risk may be on the same order of magnitude as the benefit observed in the NLST. Optimal screening strategy remain uncertain, CT lung cancer screening is not yet ready for implementation. 2. Computed tomographic colonography is as good as colonoscopy for detecting colon cancer and is almost as good as colonoscopy for detecting advanced adenomas, but significantly less sensitive and specific for smaller lesions and disadvantageous for subsequent therapeutic optical colonoscopy if polyps are detected. The average effective dose from CT colonography was estimated 8-10 $mS{\nu}$, which could be a significant dose if administered routinely within the population over many years. CT colonography should a) achieve at least 90% sensitivity and specificity in the size category from 6 and 10 mm, b) offer non-cathartic bowl preparation and c) be optimized and standardized CT parameters if it is to be used for mass screening. 3. There is little evidence that demonstrates, for whole-body scanning, the benefit outweighs the detriment. This test found large portion of patient(86~90.8%) had at least one abnormal finding, whereas only 2% were estimated to have clinically significant disease. Annual scans from ages 45 to 75 years would accrue an estimated lifetime cancer mortality risk of 1.9%. There is no group within the medical community that recommends whole-body CT. No good studies indicate the accuracy of screening CT, at this time. The benefit/risk balance for any of the commonly suggested CT screening techniques has yet to be established. These areas need further research. Therefore wild screening should be avoided.

• Sleep Medicine and Psychophysiology
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• v.3 no.1
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• pp.56-67
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• 1996

Objectives : This study was designed to find clinical factors that could be differentiated by the lateralization of lesion and also find clinical factors to predict the lateralization of lesion. Methods : The subjects were 65 cooperative inpatients and outpatients with non-traumatic subcortical cerebrovascular disease without neurologic and psychiatric history from January 1995 to September 1995 ; 48 patients in Kyung Hee University, Oriental Medicine Hospital, 35 patients in Anam Hospital, Korea University were examined as subjects, but authors excluded 20 patients whose data were incomplete or who had uncertain lesions on brain CT or MRI. The 65 patients were divided into three groups-group with left hemispheric lesion, group with right hemispheric lesion, group with both hemispheric lesion-according to the finding of brain imaging study. Their cognitive functions were evaluated by the Benton Neuropsychological Assessment(BNA), their subjective neurobehavioral symptoms by Symptom Check List-90-R(SCL-90-R), their objective neurobehavioral symptoms by Neurobehavioral Rating Scale, and their daily living functions by Geriatric Evaluation by Relative's Rating Instrument(GERRl) and Instrumental Activities of Daily Living Scale(IADLs). Results : The results were as follows : 1) The results of cognitive function test indicated that the group with right hemispheric lesion showed low functions in Tactile Form Perception(left), the group with left hemispheric lesion showed low functions in Finger localization(right), the group with right hemispheric lesion showed low functions in Finger Localization(left). 2) Though, there were little significant differences in subjective neurobehavioral symptoms, the group with right hemispheric lesion showed higher scores in all symptoms except hostility. 3) Though, there were little significant differences in objective neurobehavioral symptoms, the group with both hemispheric lesion showed higher scores in cognition, guilty/disinhibition, the group with left hemispheric lesion showed higher scores in lability of mood, the group with right hemispheric lesion showed highest scores in psychotism, neurotism, agitation-hostility and decreased motivation/emotional withdrawal. 4) There were little significant differences among three groups in Daily Living Functions, but the group with right hemispheric lesion showed the lowest functions in Instrumental Activities of Daily Living. 5) As a result of discriminant analysis on each factor's contribution to the prediction of lesion, Finger Localization(left), Phoneme Discrimination and Tactile Form Perception(right) showed that they had the potentiality to predict lesion. Conclusion : The results suggest that there are little significant differences among the groups of three non-traumatic subcortical cerebrovascular disease in cognitive functions, but the group with right hemispheric lesion showed more serious and various changes in subjective and objective neurobehavioral symptoms, and showed low functions in Instrumental Activities of Daily Living. This results suggest the possibility that the decline of the daily living function in the group with right hemispheric lesion were due to various symptoms, not due to cognitive dysfunction. The confirmation of the possibility should be worked out through the follow-up study of some groups containing cortical lesion. Apart from these findings, Finger Localization, Tactile Form Perception(right) and Phoneme Discrimination suggest that they can be used as clinically valuable cognitive parameters that predict the lateralization of lesion in non-traumatic cerebrovascular disease.

• Tuberculosis and Respiratory Diseases
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• v.50 no.2
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• pp.196-204
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• 2001

Background : Bronchial asthma is characterized by a reversible airway obstruction, airway hyperresponsiveness, and eosinophilic airway inflammation. The bronchodilator response(BDR) after short acting beta agonist inhalation and PC20 with methacholine inhalation are frequently used for diagnosing bronchial asthma. However, the relationship between the presence of a bronchodilator response and the degree of airway hyperresponsiveness is uncertain. Therefore, the availability of a eosinophil cationic protein (ECP) and a correlation ECP with a bronchodilator response and airway hyperresponsiveness was investigated. Method : A total 71 patients with a moderate to severe degree of bronchial asthma were enrolled and divided into two groups. 31 patients with a positive bronchodilator response and 38 patients with a negative bronchodilator response were evaluated. In both groups, the serum ECP, peripheral blood eosinophil counts, and total IgE level were measured and the methacholine bronchial provocation test was examined. Results : There were no differences observed in age, sex, atopy, and baseline spirometry in both groups. The peripheral eosinophil counts showed no difference in both groups, but the ECP level in group 1 (bronchodilator responder group) was higher than in group 2(non-bronchodilator responder group) ($22.4{\pm}20.7$ vs $14.2{\pm}10.4$, mean$\pm$SD). The PC20 in group 1 was significantly lower than in group 2 ($1.14{\pm}1.68$ vs $66{\pm}2.98$). There was a significant positive correlation between the BDR and ECP, and a negative correlation between the bronchial hyperresponsiveness and ECP. Conclusion : The bronchodilator response significantly correlated with the bronchial hyperresponsiveness and serum ECP in the moderate to severe asthma patients. Hence, the positive bronchodilator response is probably related with active bronchial inflammation and may be used as a valuable index in treatment, course and prognosis of bronchial asthma.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.536-542
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• 2007

Behcet's disease (BD) is a chronic inflammatory disorder, involving several organs. Inflammation in the disease is thought to be mediated by cytokines derived from T-helper type 1 (Th1) lymphocytes. Although the exact pathogenesis for BD is not completely understood, it has been suggested that the disease is triggered in genetically susceptible individuals by environmental factors, such as microbial agents. It is noted that multiple genes, including MHC (major histocompatibility complex) and non-MHC genes, are implicated in the pathogenesis of BD. This study tries to determine whether HLA-B51, IL-18, SLC11A1 and TNF-α polymorphisms are associated with susceptibility to Behcet's disease in Koreans. As a results, HLA-B51 was a genetic factor with the strongest association with BD. But it is still uncertain whether this HLA molecule is directly involved in the pathogenesis of BD. Although the IL-18 gene polymorphisms were not associated with a susceptibility to BD in the Korean population, the patients carrying the GG genotype at position 137 had a higher risk of developing the ocular lesions. This study suggests that the allele 3 and the genotype allele 3 / allele 3 of 5'-promoter (GT)n polymorphism in the SLC11A1 gene may have a protective effect for the development of BD in the Korean population. There were no evidences for genetic association conferred by the TNF-α gene with respect to susceptibility to BD.

• Journal of Korea Water Resources Association
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• v.53 no.6
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• pp.427-436
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• 2020

It is uncertain how global climate change will influence future drought characteristics over the Korean peninsula. This study aims to project the future droughts using climate change and land use change scenarios over the Korean peninsula with the land surface modeling system, i.e., Weather Research and Forecasting Model Hydrological modeling system (WRF-Hydro). The Representative Concentration Pathways (RCPs) 2.6 and 8.5 are used as future climate scenarios and the Shared Socio-economic Pathways (SSPs), specifically SSP2, is adopted for the land use scenario. The using Threshold Level Method (TLM), we identify future hydrological and ecological drought events with runoff and Net Primary Productivity (NPP), respectively, and assess drought characteristics of durations and intensities in different scenarios. Results show that the duration of drought is longer over RCP2.6-SSP2 for near future (2031-2050) and RCP8.5-SSP2 (2080-2099) for the far future for hydrological drought. On the other hand, RCP2.6-SSP2 for the far future and RCP8.5-SSP2 for the near future show longer duration for ecological drought. In addition, the drought intensities in both hydrological and ecological drought show different characteristics with the drought duration. The intensity of the hydrological droughts was greatly affected by threshold level methods and RCP2.6-SSP2 for far future shows the severest intensity. However, for ecological drought, the difference of the intensity among the threshold level is not significant and RCP2.6-SSP2 for near future and RCP2.6-SSP2 for near future show the severest intensity. This study suggests a possible future drought characteristics is in the Korea peninsula using combined climate and land use changes, which will help the community to understand and manage the future drought risks.

• Tuberculosis and Respiratory Diseases
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• v.40 no.4
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• pp.367-377
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• 1993

Background: The benefits of combination chemotherapy in unresectable non-small cell lung cancer remain uncertain. But, according to the recent reports, the response rates of cisplatin-based polychemotherapy regimens are higher than those of single agent. Also, the response rates of high-dose cisplatin group are higher than those of low-dose cisplatin group. In attemp to answer the question whether treatments, combination chemotherapy (high VPP) and combination chemotherapy with radiation therapy, improve survival in advanced non-small cell lung cancer, we begin to study. Method: Thirty-five patients above stage III, diagnosed histologically as non-small cell lung cancer, were enrolled. Among them, nineteen received a combination chemotherapy consisting of VP-16 & high-dose cisplatin (100 $mg/m^2$) and/or radiation therapy. The other group (16 subjects) received no therapy. To investigate the differences of survival and response rates between two groups and the side effects related to therapy, we reviewed patients' records. Results: 1) The overall objective response rate was 47%(9/19) with one complete remission. 2) In patients who received polychemotherapy and radiation therapy, the response rate was 60%(6/10) with one complete remission and survival rates of 3 months, 6 months and 12 months were 100%, 70% and 40%. 3) In patients who received polychemotherapy, the response rate was 33% (3/9) with no complete remission and survival rates of 3 months, 6 months and 12 months were 78%, 67% and 33%. 4) Overall, treated patients survived significantly longer (p<0.05) than non-treated patients (median survival 307 days versus 95 days). 5) Analysis of the various prognostic factors disclosed that good performance status, stage III and squamous cell type showed the good response rates. 6) The toxicities were nausea and/or vomiting (100%), alopecia (90%), anemia (79%), leukopenia (69%), thrombocytopenia (2%), increased creatinine (16%) and neurotoxicity (5%). Conclusion: According to above results, there are relatively good results that high VPP combination chemotherapy in advanced non-small cell lung cancer improves survival in the treated group than in the non-treated group. Thus, it is considerd that we select the patients with proper indications and treat them with effective chemotherpy and radiation therapy. But, because improvement related to high VPP ploychemotherapy is not marked in this study, it is necessary that we should investigate follow-up studies in many cases.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.607-614
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• 2001

Background : Residual pleural thickening is frequently seen following treatment for tuberculous pleurisy, and pleural decortication is performed occasionally in patients with severe residual pleural thickening. However, predictive factors for the development of residual pleural thickening are uncertain at the initial diagnosis of the tuberculous pleurisy. Therefore, the purpose of this study was to identify the associated factors for residual pleural thickening at initial diagnosis. Methods : We separated 63 patients diagnosed as tuberculous pleurisy into two groups; group 1 consisted of patients without residual pleural thickening and group 2 comprised patients with residual pleural thickening at the end of tuberculous pleurisy treatment. We analyzed the clinical characteristics, radiological findings, pleural biopsy and characteristics of pleural fluid between group 1 and group 2. Results : The study population and clinical symptoms of the two groups were not significantly different and the duration of symptoms before treatment and the peripheral WBC were similar between the two groups. The presence of pulmonary tuberculosis, pleural fluid loculation or the amount of pleural effusion sid not differ significantly between the two groups. The incidence of positive AFB staining(group 1 : 8%, group 2 : 38%) and granuloma(group 1 : 30%, group 2: 62%)on pleural biopsy specimens was significantly higher in group 2 than in group 1. Pleural fluid WBC and differential count, adenosine deaminase level, pH, protein level or glucose level did not differ between the two groups. However, group 2 had higher LDH levels ($1370{\pm}208mg/dL$) than group 1 ($860{\pm}71mg/dL$, p<0.05). Conclusion : In tuberculous pleurisy, patients with residual pleural thickening following treatment demonstrated a higher incidence of positive AFB staining and granuloma on the pleural biopsy specimens or higher LDH level in the pleural fluid than patients without residual pleural thickening From these results, we speculate that the amount of tuberculous bacilli and granuloma are probably correlated with residual pleural thickening in the tuberculous pleurisy.

• Management & Information Systems Review
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• v.36 no.3
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• pp.219-237
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• 2017

Looking into the top-five innovative sectors in Korea's manufacturing and service industries, this study empirically analyzes the effect of innovation performance on R&D investment, which is one of the most important strategic decisions for corporate management. In the midst of an uncertain business environment, R&D investment has been regarded as the most important strategic decision making in corporate management related to innovation. Corporate management, however, tend to be reluctant to make sufficient R&D investment due to the risk of an investment failure. Therefore, having R&D investment by offsetting this risk has been deemed as a key task for corporate management. However, prior studies have failed to identify which factors affect companies' strategic decision making on R&D investment. This study is to remedy this weakness of prior study. Relying on path dependency theory at organization-level and dominant logic at individual-level, this study empirically examines the multiple regression model, which sees entrepreneurial orientation as a positive mediator between innovation performance and R&D investment. The results found in the analysis of 242 local companies in the manufacturing and service sectors represent that innovation performance has a direct and positive effect on R&D investment, while it indirectly affects R&D investment through the mediating roles of entrepreneurial orientation. They also revealed that innovation performance had a meaningful impact on entrepreneurial orientation, which is an inclination to seek innovation, led to R&D investment. The founding of this study imply that innovation performance in the past affects innovation strategies in the future, and such a relationship could be strengthened by entrepreneurial orientation as the dominant logic of corporate management.

• Journal of the Korean Society of Costume
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• v.5
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• pp.41-63
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• 1981

The mural portraits of the ancient Dukheungri tombs are very important for the study of our traditional costume because the tomb contains a stone. with the in-scription of the date of its erection, 408 A.D. and the name, and official status of the buried. The costumes shown in the mural paintings will be the basis on which historical research can be made concerning costumes before and after 400 A. D. The costume in the mural paintings is classified into five different categories; You (jacket), Po (overcoat), Go (trousers), Sang (skirt), and Gwan (hat). Comparing these categories with those of other mural paintings lead us to the following conclusions. 1. The length of the You (jacket) reaches below the buttocks and the sleeves are narrow. The edges of the sleeves are decorated with stripes. The You (jacket) over-laps on the right, center, and left sides, and there are many Jikryong (V-collar) and Danryong (rounded collar) styles, but it has a similar tendency to others of the Pyongyang area which exhibit many foreign influences. In a departure from tradition. the belts on the men's You (jackets) have only 3 knots in the front, with the back having more knots than the front. The belts of the women's You (jacket) seem to have had a band or button for fastening. We must re-evaluate the assumption that the You (jacket) and Go (trousers) of the northern peoples had the common characters of a belted You (jacket) and Po (over-coat) and that the Gorum originated from the Goryo or Unified Silla dynasty. The outside of the sleeves are longer and more to the side than the inner garment (underwear) so that the sleeves of the inner garment frequently overlapped the outer dress. The above mentioned facts have lead to the discovery of the "Hansam," "Tosi" and "Geodoolgi." 2. The Po (overcoat) was used only by the upperclasses and differs from those found in other mural tombs. The Po (overcoat) of the noble on the tomb mural is centered with an overlapping Jikryong (V-collar) while the other Po (overcoats) of the upperclasses are characterized by an overlap on the left, a Danryong (rounded collar) with two types of sleeves (wide and narrow). Foreign influences and traditional influences coexist in Po (overcoat). Belts have frontal knots without exceptions. The facts that the belts on the You (jackets) are on the front and the belts on the Po (overcoats) are on the back must be reexamined. 3. Go (trousers) is usually narrow, being wider in the rear and narrower below the knees. They were used by hunters on the back of horses with similar Go (trousers) from the Noinwoowha tombs being typical of the northern peoples. 4. Sang (skirts) are pleated as commonly seen in the Goguryo murals. The size of the pleat is varied, each pleat being characteristically wider and having different colors. Same types of pleat are discovered in Central Asia and China. It is uncertain whether the pleat of Goguryo was originated in Central Asia and China or only interrelated with those of the areas. 5. There are three kinds of Gwan (hats); Nagwan, Chuck, and Heukgun. Nag-wan was worn by the dead lords and their close relations. Chuck has three cone shaped horns. Heukgun was worn by military bandmen and horsemen. There are two kinds of hair styles. The up-style was used by the upperclass people closely related to lords, and other people used the Pungimoung hair style. The hair styles of the men and women are characterized by the Pungimoung style. which is a Chinese influence, but still retain their originality. The costume has a similar tendency from those from Yaksuri mural tombs, Anak No. 2 and Anak No. 3. We need to reexamine the costumes from $4{\sim}5$ century murals according to the Dukheungri murals. The costumes of Goguryo share many common factors with those of Western Asia, Central Asia and Ancient China (Han). It seems due to the cultural exchanges among the Northern peoples, the Western and Central Asians, and the Ancient Chinese. It may have resulted from the structural identity or morphological identity of the peoples, or their common social and natural environments and life styles. It will be very valuable to study the costumes of Japan, China, and Korea to find out the common factors. It is only regretful that the study is not based on direct observations but reported information made by 77 persons, because Dukheungri is an off-limits area to us.

• Korean Journal of Environment and Ecology
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• v.25 no.4
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• pp.601-613
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• 2011

The purpose of this study is to provide an protected wildlife species and potential habitats in Seoul through the overall present status of the species which live in Seoul. This study was performed in Seoul, the entire area of which is 605.52 $km^2$. We analyzed a total of 57 studies, including academic papers and research reports, for the natural ecology in Seoul. As for the results from the study, it was found that a total 1,907 species from 5 taxa were inhabiting and growing within the area. Among the total, plants of 1,656 species accounted for 86.7%, 197 species of wild birds made up 10.3%, 29 species of amphibians and reptiles consisted of 1.5%, and 27 species of mammalia totaled 1.4%. A total of 440 species except foreign species and species legally preserved by the Ministry of Environment, common species and uncertain species were selected as primary candidates. By taxon, it shows 212 species of plants, 180 species of wild birds, 24 species of mammalia, and 24 species of amphibians and reptiles. For extensive research subjects and research data limited in certain insect family, analysis by literature for discovered insects was excluded. The selection criteria for the second candidate species was based on extinction crisis, rarity, historicity and locality, academic value, habitat specificity, etc. The second candidate species from the primary species were selected through taxon experts' evaluations. As for the results of the selection of the second candidates, a total 77 species were selected through the experts' evaluations. Each species by taxon was 25 species for plants, 21 species for wild birds, 5 for mammalia, 10 for amphibians and reptiles and 16 species for insects. A site investigation for the second candidates was conducted to select the final candidate species. For the target areas, the habitats of the second candidates given by the literature and 46 potential areas in Seoul, which show good natural resistance, were finally selected. From the result of the site investigation, it was found that 14 species of plants, 19 species of wild birds, 2 species of mammalia, 4 species of amphibians and reptiles, and 16 species of insects were actually inhabiting Seoul; thus, the final 55 protected species were selected.