• Environmental and Resource Economics Review
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• v.13 no.1
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• pp.49-82
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• 2004

The study aimed to evaluate cancer damage cost due to risk from benzene inhalation. We performed health risk assessment based on US EPA guideline to estimate annual population risk in Ulsan metropolitan city. Also, we estimated a willingness-to-pay amount for reducing a cancer mortality rate to evaluate a value of statistical life. We combined the annual population risk and the value of statistical life to calculate the cancer damage cost. In the health risk assessment, we applied the benzene unit risk ($2.2{\times}10^{-6}{\sim}7.8{\times}10^{-6}$) in the US EPA'S Integrated Risk Information System to assess the annual population risk. Average concentration of benzene in ambient air is $7.88{\mu}g/m^3$(min: 1.16~max: $23.32{\mu}g/m^3$). We targeted an exposure population of 516,641 persons who aged over 30 years old. Using a Monte-Carlo simulation for uncertainty analysis, we evaluated that the population risk of benzene during ten years in Ulsan city is 2.90 persons (5 percentile: 0.32~95 percentile: 9.11persons). And the monthly average WTP for 5/1,000 cancer mortality reduction during ten years is 14,852 Won(95% C.I: 13,135~16,794 Won) and the implied VSL is 36 million Won(95% C.I: 30~40 million Won). Cancer damage cost due to risk from benzene inhalation during 10 years in Ulsan city is about 104 million Won(5 percentile: 13~95 percentile: 328 million Won). Health benefit cost to reduce a cancer mortality risk of benzene is about 50 million Won is Ulsan metropolitann city. But, it is very important that this cost is not for all health damage cost of cancer mortality in some area. We just recommended a model for evaluating a cancer risk reduction, so we must re-evaluate an integrated application of total VOCs damage cost including benzene.

• The Journal of Korean Society for Radiation Therapy
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• v.25 no.1
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• pp.57-67
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• 2013

Purpose: Replacing the film which used to be used for checking the set-up of the patient and dosimetry during radiation therapy, more and more EPID equipped devices are in use at present. Accordingly, this article tried to evaluated the accuracy of the position check-up and the usefulness of dosimetry during the use of an electronic portal imaging device. Materials and Methods: On 50 materials acquired with the search of Korea Society Radiotherapeutic Technology, The Korean Society for Radiation Oncology, and Pubmed using "EPID", "Portal dosimetry", "Portal image", "Dose verification", "Quality control", "Cine mode", "Quality - assurance", and "In vivo dosimetry" as indexes, the usefulness of EPID was analyzed by classifying them as history of EPID and dosimetry, set-up verification and characteristics of EPID. Results: EPID is developed from the first generation of Liquid-filled ionization chamber, through the second generation of Camera-based fluoroscopy, and to the third generation of Amorphous-silicon EPID imaging modes can be divided into EPID mode, Cine mode and Integrated mode. When evaluating absolute dose accuracy of films and EPID, it was found that EPID showed within 1% and EDR2 film showed within 3% errors. It was confirmed that EPID is better in error measurement accuracy than film. When gamma analyzing the dose distribution of the base exposure plane which was calculated from therapy planning system, and planes calculated by EDR2 film and EPID, both film and EPID showed less than 2% of pixels which exceeded 1 at gamma values (r%>1) with in the thresholds such as 3%/3 mm and 2%/2 mm respectively. For the time needed for full course QA in IMRT to compare loads, EDR2 film recorded approximately 110 minutes, and EPID recorded approximately 55 minutes. Conclusion: EPID could easily replace conventional complicated and troublesome film and ionization chamber which used to be used for dosimetry and set-up verification, and it was proved to be very efficient and accurate dosimetry device in quality assurance of IMRT (intensity modulated radiation therapy). As cine mode imaging using EPID allows locating tumors in real-time without additional dose in lung and liver which are mobile according to movements of diaphragm and in rectal cancer patients who have unstable position, it may help to implement the most optimal radiotherapy for patients.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.5
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• pp.488-496
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• 2017

Emissions of pollutants from ship-based sources are controlled by the International Maritime Organization (IMO). Since pollutants emitted from ship may be dispersed to the land, controlling emissions from ships is necessary for efficient air quality management in Incheon, where exposure to ship-based pollution is frequent. It has been noted that the ratios of air pollutant emissions from coastal areas to inland areas are about 14% for NOx and 10% for SOx. The air quality of coastal urban areas is influenced by the number of ships present and the dispersion pattern of the pollutants released depending on the local circulation system. In this study, the dispersion of pollutants from ship-based sources was analyzed using the numerical California Puff Model (CALPUFF) based on a meteorological field established using the Weather Research and Forecasting Model (WRF). Air pollutant dispersion modeling around coastal urban regions such as Incheon should consider point and line sources emitted from both anchored and running ships, respectively. The total average NOx emissions from 82-84 ships were 6.2 g/s and 6.8 g/s, entering and leaving, respectively. The total average SOx emissions from 82-84 ships, entering and leaving, were 3.6 g/s and 5.1 g/s, respectively. The total average emissions for NOx and SOx from anchored ships were 0.77 g/s and 1.93 g/s, respectively. Due to the influence of breezes from over land, the transport of pollutants from Incheon Port to inland areas was suppressed, and the concentration of NOx and SOx inland were temporarily reduced. NOx and SOx were diffused inland by the sea breeze, and the concentration of NOx and SOx gradually increased inland. The concentration of pollutants in the area adjacent to Incheon Port was more influenced by anchored ship in the port than sea breezes. We expect this study to be useful for setting emission standards and devising air quality policies in coastal urban regions.

• Clinical and Experimental Pediatrics
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• v.49 no.4
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• pp.410-416
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• 2006

Purpose : Ciliary abnormalities of the respiratory system usually accompany recurrent or persistent respiratory diseases such as paranasal sinusitis, bronchiectasis, rhinitis, and/or otitis media, since they cause certain derangements in ciliary cleaning activities. This disease is usually inherited by autosomal recessive trait, but may also be found to be acquired or transient in rare cases after heavy exposure to pollutants, cigarette smoking or severe infection. We performed this study in children with frequently recurrent or persistent respiratory diseases to clarify if the ciliary abnormalities are preceding factors. Methods : We enrolled 17 children with suspected respiratory ciliary abnormalities. The indications for evaluation of ciliary ultrastructure were recurrent or persistent respiratory infections. Children with immunologic abnormalities were excluded. From August 2000 to July 2003, we performed a biopsy on nasal mucosa and examined the structure of ciliary status by using an electron microscope. Results : Of the subjects, there were seven males and 10 females, aged 2 to 10 years. Out of the 17 subjects, 12 cases of chronic paranasal sinusitis, nine chronic coughs, nine frequent upper respiratory infections, seven cases of recurrent otitis media, four cases of recurrent pneumonia, and four cases of bronchial asthma were found. Out of the 17 cases on which histologic examinations were conducted, four cases showed pathologic findings, including one case of inner dynein arm defect, one of microtubular transposition, one of supernumerous tubules, and one singlet, respectively. Conclusion : It is essential for differential diagnosis and effective treatment to identify the abnormalities of ultrastructure of nasal cilia in children with symptoms of frequently recurrent or persistent respiratory diseases, if immunodeficiency or respiratory allergy could be excluded.

• Tuberculosis and Respiratory Diseases
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• v.52 no.3
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• pp.241-250
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• 2002

Background : Coal-worker's pneumoconiosis(CWP) is characterized by a chronic inflammatory lung reaction associated with macrophage accumulation in the alveolar spaces. CWP is usually divided into two stage : simple pneumoconiosis(SP) where there are a limited number of fibrotic lesions remain limited, with radiological opacities smaller than 1cm and progressive massive fibrosis(PMF), which is characterized by the development of a perifocal extensive fibrotic response of the lung and severe alterations in pulmonary function. In this study, the lymphocyte compartment and cytokine were evaluated by measuring the serum levels in the control, SP and PMF groups. Materials and Methods : The coal workers selected for this study were employees(patients?) of the Tae-Baek and Dong-Hae hospital. All were men, 45-76 years old and the mean duration of their exposure to coal dust was 23.2 years in the lymphocyte compartment and 24.3 years in the cytokine checked group. According to X-ray examination results, the patients were classified into either one of the SP, PMF categories. The normal controls examined were 26-70 years old men. The serum cytokine levels were estimated by using an end point enzyme immunoassay technique. Results : T lymphocyte, helper and suppressor T cells were highly related to pneumoconiosis in this study. A statistically significant decrease in the number of suppressor T lymphocytes was observed in the simple pneumoconiosis patients and at the same time, there was an increase in the lymphocyte index. Howevere, there was no statistically difference in the serum cytokines levels among the SP, PMF and control groups. Conclusion : T lymphocyte, helper T, and suppressor T cells may be highly related to the development of CWP compared to the control group particularly in the early stage of pneumoconiosis. The changes observed in the immunological system in patients with pneumoconiosis may lie at the bottom of the pathogenesis of fibrosis. Further study is needed to evaluate the lymphocyte compartment as a marker for pneumoconiosis development in the early stage.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1238-1243
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• 2008

The root of Adenophora triphylla is widely used as traditional herbal medicine in Korea. We studied its effects on sodium nitroprusside (SNP) cytotoxicity and antioxidant genes expression in HepG2 cells. To study whether Adenophora triphylla ethylacetate extract (ATea) inhibited NO-induced cell death, HepG2 cells were preincubated for 24 hr with 50 and 100 $\mu$g/mL ATea followed by 24-hr exposure to 0.5 mM SNP (exogenous NO donor). No-induced cytotoxicity was inhibited by pretreatment of ATea, as assessed by mitochondrial dehydrogenase activity (MTT assay). We further investigated the effects of ATea on mRNA levels of various enzymes of the antioxidant system such as Cu, Zn superoxide dismutase (SOD 1), Mn SOD (SOD 2), glutathione peroxidase (GPx), catalase and several enzymes of the glutathione metabolism [glutathione reductase (GR), $\gamma$-glutamyl-cystein synthetase (GCS), glutathione-S-transferase (GST), $\gamma$-glutamyltranspeptidase ($\gamma$-GT), glucose-6-phosphate dehydrogenase (G6PD)] by RT-PCR. CAT, GCS, GR and G6PD mRNA levels were increased after treatment with ATea. The SOD 1, SOD 2, GPx, GST and $\gamma$-GT mRNA levels were not affected in ATea-treated HepG2 cells. We concluded that ATea have an indirect antioxidant effects, perhaps via induction of CAT, GCS, GR and G6PD.

• Journal of Intelligence and Information Systems
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• v.24 no.2
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• pp.37-57
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• 2018

With the spread of smart phones, interest in mobile media is on the increase as useful media recently. Mobile media is assessed as having differentiated advantages from existing media in that not only can they provide consumers with desired information anytime and anywhere but also real-time interaction is possible in them. So far, studies on mobile advertising were mostly researches analyzing satisfaction with, and acceptance of, mobile advertising based on survey, researches focusing on the factors affecting acceptance of mobile advertising messages and researches verifying the effect of mobile advertising on brand recall, advertising attitude and brand attitude through experiments. Most of the domestic mobile advertising studies related to advertisement effect and advertisement attitude have been conducted through experiments and surveys. The advertising effectiveness measure of the mobile ad used the attitude of the advertisement, purchase intention, etc. To date, there have been few studies on the effects of mobile advertising on actual advertising data to prove the characteristics of the advertising platform and to prove the relationship between the factors influencing the advertising effect and the factors. In order to explore advertising effect of mobile advertising platform currently commercialized, this study defined advertising characteristics and media characteristics from the perspective of advertiser, advertising platform and publisher and analyzed the influence of each characteristic on advertising effect. As the advertisement characteristics, we classified advertisement format classified by bar type and floating type, and advertisement material classified by image and text. We defined advertisement characteristics of advertisement platform as Hedonic and Utilitarian media characteristics. As a dependent variable, we use CTR, which is the ratio of response (click) to ad exposure. The theoretical background and the analysis of the mobile advertising business, the hypothesis that the advertisement effect is different according to the advertisement specification, the advertisement material, In the ad standard, bar ads are classified as static framing, Floating ads can be categorized as dynamic framing, and the hypothetical definition of floating advertisements, which are high-profile dynamic framing ads, is highly responsive. In advertising, images with high salience are defined to have higher ad response than text. In the media characteristics classified as practical / hedonic type, it is defined that the hedonic type media has a more relaxed tendency than the practical media, and there is a high possibility of receiving various information because there is no clear target. In addition, image material and hedonic media are defined to be highly effective in the interaction between advertisement specification and advertisement material, advertisement specifications and media characteristics, and advertisement material and media characteristics. As the result of regression analysis on each characteristic, material standard, which is a characteristic of mobile advertisement, and media characteristics separated into 'Hedonic' and 'Utilitarian' had significant influence on advertisement effect and mutual interaction effect was also confirmed. In the mobile advertising standard, the advertising effect of the floating advertisement is higher than that of the bar advertisement, Floating ads were more effective than text ads for image ads. In addition, it was confirmed that the advertising effect is higher in the practical media than the hedonic media. The research was carried out with the big data collected from the mobile advertising platform, and it was possible to grasp the advertising effect of the measure index standard which is used in the practical work which could not be grasped in the previous research. In other words, the study was conducted using the CTR, which is a measure of the effectiveness of the advertisement used in the online advertisement and the mobile advertisement, which are not dependent on the attitude of the ad, the attitude of the brand, and the purchase intention. This study suggests that CTR is used as a dependent variable of advertising effect based on actual data of mobile ad platform accumulated over a long period of time. The results of this study is expected to contribute to establishment of optimum advertisement strategy such as creation of advertising materials and planning of media which suit advertised products at the time of mobile advertisement.

• Progress in Medical Physics
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• v.24 no.2
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• pp.119-126
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• 2013

Due to the introduction of CR and DR, it has been neglected the use of the X-ray beam collimator and field size. This study examines nationwide survey of the proper use of collimator and field size by area in a specific field of plain radiography and the current status. Authors emphasized the need for the field size criteria, and propose a standard reference field size in each specific radiologic examination. Total 333 medical institutions (included in Seoul, Gyeonggi-do, Jeolla, Chungcheong, Gangwon-do, Busan area), were investigated in relation to the status of the X-ray beam collimation field size, type specific inspection areas, medical facilities, and image analyses by type to figure out whether they use the adjustment of image field to the specific examination. To assess the awareness and the impact of radiation exposure to the collimation adjustable, 168 radiographers who was working in 10 general hospitals, 10 hospitals, and 10 clinics, were surveyed how they haver adjusted the actual field size. We examine that 61.3% of medical institutions used the "Proper collimation" and only 49.9% of them employed proper one in lumbar spine densely crowded by major organs. 69% among general hospitals, and 65% among hospitals using DR system were using proper collimation. Radiographers recognized that proper adjustment of collimation could reduce the harmful radiation dose on patients. In the survey, 97.6% of respondents were aware of this fact, but only 83.3% of respondents did the adjustment of the size of the collimation field. The using of proper collimation field was low in the nationwide survey, so the effort to reduce the radiation dose on the patients is urgently needed. A unified standard for the field accompanied by thorough education should be needed.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.35 no.4
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• pp.287-292
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• 2009

Human skin is constantly exposed to environmental irritants such as smoke, chemicals and ultraviolet (UV). Free radicals and reactive oxygen species (ROS) caused by these environmental irritants play critical roles in cellular damage. In this study, to investigate the skin cell protective effect of Ophioglossum vulgatum extract, we investigated its effects on intercellular antioxidative activity and UVA-induced MMP expression in human dermal fibroblasts (HDFs). The dried O. vulgatum was extracted in a mixture of ethanol and water (1 : 1) for 24 h at room temperature. The extract was filtered and concentrated in vacuo and lyophilized. For testing intracellular ROS scavenging activity the cultured HDFs were analyzed by increase in DCF fluorescence upon exposure to UVB $20\;mJ/cm^2$. After treatment of O. vulgatum extracts, intracellular ROS levels were measured by luminescence spectrophotometer. Enzyme linked immuno sorbent assay (ELISA), and RT-PCR techniques were used for evaluating the effects of O. vulgatumon on MMP protein and mRNA expression in UVA irradiated HDFs. O. vulgatum extract was found to have ROS scavenging activity with the $IC_{50}$ values of $18.2\;{\mu}g/mL$ against superoxide radicals in the xanthine/xanthine oxidase system. After treatment of O. vulgatum extracts, the oxidation of CM-DCFDA was inhibited effectively and O. vulgatum extracts showed a potent free radical scavenging activity by 30.4 % at $100\;{\mu}g/mL$ in UVB-irradiated HDFs. UVA induced MMP protein expression was reduced 37.7 % by treatment with O. vulgatum extract, and MMP-1 mRNA expression was reduced in a dose-dependent manner. Taken together, these results suggest that O. vulgatum extract prevents the skin cell damage induced by UV irradiation, and implies that O. vulgatum extract may be useful as a new ingredient for anti-aging cosmetics.

• 한국환경농학회:학술대회논문집
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• 2009.07a
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• pp.273-282
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• 2009

The transmissible spongiform encephalopathies (TSEs) disease group are fatal neurodegenerative disorders affecting a wide range of hosts. The group includes kuru and Creutzfeldt-Jakob disease (CJD) in humans, scrapie in sheep and goats and Bovine spongiform encephalopathy (BSE) in cattle. The exact nature of the infectious agent involved in the transmission of these diseases remains controversial. However, a central event in their pathogenesis is the accumulation in infected tissues of an abnormal form of a host-encoded protein, the prion protein (PrP). Whereas the normal cellular protein is fully sensitive to protease ($PrP^{sen}$), the disease-associated prion protein ($PrP^d$) is only partly degraded ($PrP^{res}$), its amino-terminal end being removed. BSE was first reported in the mid-80s in the UK. Ten years later, a new form of human prion disease, variant CJD (vCJD) developed in the wake of the BSE epidemic, and there is now strong scientific evidence that vCJD was initiated by the exposure of humans to BSE-infected tissues, thus indicating a zoonotic disease. However, the ban on the feeding of animal-derived proteins to ruminants, and the apparent lack of vertical transmission of BSE, have led to a decline in the incidence of the disease within cattle herd and therefore, an assumed decreased risk for human contacting vCJD. The origin of the original case(s) of BSE still remains an enigma even though three hypotheses have been raised. Hypotheses are i) sheep- or goat-derived scrapie-infected tissues included in meat and bone meal fed to cattle, ii) a previously undetected sporadic or genetic bovine TSE contaminating cattle feed or iii) originating from a human TSE through animal feed contaminated with human remains. A host cellular membrane protein ($PrP^C$), which is abundant in central nervous system tissue, appear to be conformationally altered in the diseased host into a prion protein ($PrP^{Sc}$). This $PrP^{Sc}$ is detergent insoluble and partially protease-resistant ($PrP^{res}$). The term $PrP^{res}$ is normally used to describe the protein detected after protease treatment, in techniques such as Western immunoblotting, and enzyme-linked immunosorbant assay using fresh/frozen tissue. Immunohistochemistry may performed with formalin-fixed tissues. Also, clinical signs of the BSE are one of the major diagnostic indicators. Recently, atypical forms (known as H- and L-type) of BSE have appeared in several European countries, Japan, Canada and the United States. An unusual case was also reported in a miniature zebu. The atypical BSE fall into two groups based on the relative molecular mass (Mm) of the unglycosylated $PrP^{res}$ band relative to that of classical BSE, one of the higher Mm (H-type) and the other lower (L-type). Both types have been detected worldwide as rare cases in older animals, at a low prevalence consistent with the possibility of sporadic forms of prion diseases in cattle. This raises the unwelcome possibility that vCJD could increase in the human population. Now, active surveillance program against BSE is going on in Korea. In regional veterinary service lab, ELISA is applied to screen the BSE in slaughter and confirmatory tests by Western immunoblotting and immunohistochemisty are carried out if there are positive or suspect in the screening test. Also, the ruminant feed ban is rigorously enforced. Removal of specified risk materials such as brain and spinal cord from cattle is mandatory process at slaughter to prevent the infected material from entering the human food chain.