• Atmosphere
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• v.28 no.1
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• pp.53-67
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• 2018

This study examined the lake effect of the Yellow Sea which was induced by the Siberian High pressure system moving over the open waters. The development mechanism of the convective cells over the ocean was studied in detail using the Weather Research and Forecasting model. Numerical experiments consist of the control experiment (CTL) and an experiment changing the yellow sea to dry land (EXP). The CTL simulation result showed distinct high area of relative vorticity, convergence and low-level atmospheric instability than that of the EXP. The result indicates that large surface vorticity and convergence induced vertical motion and low level instability over the ocean when the arctic Siberian air mass moved south over the Yellow Sea. The sensible heat flux at the sea surface gradually decreased while latent heat flux gradually increased. At the beginning stage of air mass modification, sensible heat was the main energy source for convective cell generation. However, in the later stage, latent heat became the main energy source for the development of convective cells. In conclusion, the mechanism of the west coast heavy snowfall caused by modification of the Siberian air mass over the Yellow Sea can be explained by air-sea interaction instability in the following order: (a) cyclonic vorticity caused by diabatic heating induce Ekman pumping and convergence at the surface, (b) sensible heat at the sea surface produce convection, and (c) this leads to latent heat release, and the development of convective cells. The overall process is a manifestation of air-sea interaction and enhancement of convection from positive feedback mechanism.

• Journal of Preventive Medicine and Public Health
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• v.47 no.4
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• pp.236-243
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• 2014

Objectives: Despite the recent emphasis on a patient-centered chronic care model, few studies have investigated its use in older adults in South Korea. We explored how older Korean adults perceive and cope with their chronic illness. Methods: We conducted focus group interviews in Seoul, Korea in January 2010. Focus groups were formed by disease type (hypertension and type 2 diabetes) and gender using purposive sampling. Inclusion criteria were patients aged 60 and over who had been diagnosed with diabetes or hypertension and received care at a community health center for at least six months prior to participation. Interview data were analyzed through descriptive content analysis. Results: Among personal factors, most participants felt overwhelmed when they received their diagnosis. However, with time and control of their acute symptoms using medication, their worry diminished and participants tended to denying being identified as a patient or sick person. Among socio-familial factors, participants reported experiencing stigma with their chronic illness and feeling it was a symbol of weakness. Instead of modifying their lifestyles, which might interfere with their social relationships, they resorted to only following their medicine regime prescribed by their doctor. Participants also reported feeling that their doctor only prescribed medications and acted in an authoritative and threatening manner to induce and reinforce participants' compliance with treatment. Conclusions: For successful patient-centered management of chronic illnesses, supportive environments that include family, friends, and healthcare providers should be established.

• Environmental Analysis Health and Toxicology
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• v.9 no.1_2
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• pp.37-51
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• 1994

To evaluate the genotoxicities of workers exposed to glue and glue cleaning solution, ambient air monitoring of working place, animal study and human monitoring were carried out. By GC-MS analysis, air samples collected from shoesmaking plant were found to be toluene, xylene, cyclohexane, n-hexane, methyl ethyl ketone, trichloroethylene, butylacetate, isopropyl alcohol. Glue and glue cleaning solution from shoesmaking plant were applicated topically to the CD-1 mice. DNA was isolated from skin 24 hr following the application and analysed for DNA-adducts using the nuclease $P_1$version of $^{32}$P-postlabelling assay. RAL (Relative Adduct Labelling, adducts$10^8$ nucleotides) was significantly increased in a dose-dependent manner in the glue cleaning solution treated mice skin. Peripheral blood DNA-adducts of workers exposed to glue and glue cleaning solution were also analysed by the same method, but there were not significant differences in the peripheral blood DNA-adducts level between exposed and control workers. In addition, glue cleaning solution from shoes factory was evaluated for mutagenicity in the Salmonella plate incorporation assay using strains TA 100 and TA 1535 in the presence and absence of Arochlor 1254-induced rat liver S$_{9}$. There was evident mutagenicity for cleaning solution in TA 100 regardless of $S_9$, but TA 1535 showed positive only in the absence of $S_9$when predicted by Stead model of mutagenicity prediction (p=0.0000). The urine concentrates from workers and controls were also assayed for mutagenicity towards strain TA 100 of Salmonella typhimurium in the presence of $S_9$ using Kado's microsuspension assay, but their mutagenic activities were not found to be significant. These data suggest that shoesmaking workers are exposed to genotoxic compounds and need to be monitored by testing the mutagenicity of human urines. However, $^{32}$P-postlabelling application requires further validation for the routine monitoring of human exposure.osure.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.6
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• pp.2721-2728
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• 2012

Background: There are limited data evaluating the cost-effectiveness of gastric cancer screening using endoscopy or upper gastrointestinal x-ray in the general population. Objective: To evaluate the cost-effectiveness of population-based screening for gastric cancer in South Korea by decision analysis. Methods: A time-dependent Markov model for gastric cancer was constructed for healthy adults 30 years of age and older, and a deterministic sensitivity analysis was performed. Cost-utility analysis with multiple strategies was conducted to compare the costs and effects of 13 different screening alternatives with respect to the following eligibility criteria: age at the beginning of screening, screening interval, and screening method. The main outcome measurement was the incremental cost-effectiveness ratio. Results: The results revealed that annual endoscopic screening from ages 50-80 was the most cost-effective for the male population. In the females, biennial endoscopy screening from ages 50-80 was calculated as the most cost-effective strategy among the 12 screening alternatives. The most cost-effective screening strategy may be adjustable according to the screening costs and the distribution of cancer stage at screening. The limitation was that effectiveness data were obtained from published sources. Conclusions: Using the threshold of $19,162 per quality-adjusted life year on the basis of the Korean gross domestic product (2008), as suggested by the World Health Organization, endoscopic gastric cancer screening starting at the age of 50 years was highly cost-effective in the Korean population. The national recommendation for gastric cancer screening should consider the starting age of screening, the screening interval, and the screening modality.

• Journal of Korean Academy of Oral and Maxillofacial Radiology
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• v.27 no.1
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• pp.141-165
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• 1997

Radiation-impaired wound healing in animal experiments was believed to be an another logical experimental model to understand the wound healing mechanism in patients. The purpose of this study was to reveal the block point which would result in impaired healing. Twenty four rats(Sprague-Dawley strains) were divided into two groups according to the time interval between irradiation and wounding. Group I, observing the healing effect on the 1st day and Group II are the healing effects on the 7th days after irradiation to the wound of the rat tongue. Experimental animals were sacrificed 3, 6, 12, and 24 hours after wounding. The specimens were examined by the light microscope and transmission electron microscope. The following results were obtained 1. Fibroblasts in both groups showed degenerative changes which were dilated mitochondria and rER, reduced microorganelle, vacuoles and little cytoplasmic process. 2. Average length between bands and Quantity of the newly produced collagen fibers around fibroblasts remained unchanged against control group. 3. The severity of degenerative change of the fibroblast and impairment of wound healing including shortening of the thickness of collagen fibers were more severe in the group II than in the group I.

• Information Systems Review
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• v.9 no.3
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• pp.157-181
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• 2007

Main concerns of IT project managements are concentrated on the output control and process management. IT project, however, is difficult to measure the quality of achievement, because it produces invisible and intangible outputs. Many studies have been carried on to quantify the intangible aspects of process management. However, most of them have been focused on the technological aspects. This study measures the priority of factors to manage IT project by applying the IT-BSC and PMBOK method. Established indexes include the factors of managerial, social and future-oriented perspectives to check the different aspects of project management over the technical factors. This study uses AHP method for quantitative measurement. This study can be meaningful because of following reasons. First, this study re-arranges IT project management evaluation indexes by balanced scorecard. Second, this model includes human factors of developers and users who are directly related to the project development and operation. Third, important items of each stakeholder have been separated, and the weights of each item have been quantified to have fixed values.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.152-160
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• 2004

Radioiodide uptake in thyroid follicular epithelial cells, mediated by a plasma membrane transporter, sodium iodide symporter (NIS), provides a first step mechanism for thyroid cancer detection by radioiodide injection and effective radioiodide treatment for patients with invasive, recurrent, and/or metastatic thyroid cancers after total thyroidectomy. NIS gene transfer to tumor cells may significantly and specifically enhance internal radioactive accumulation of tumors following radioiodide administration, and result in better tumor control. NIS gene transfers have been successfully performed in a variety of tumor animal models by either plasmid-mediated transfection or virus (adenovirus or retrovirus)-mediated gene delivery. These animal models include nude mice xenografted with human melanoma, glioma, breast cancer or prostate cancer, rats with subcutaneous thyroid tumor implantation, as well as the rat intracranial glioma model. In these animal models, non-invasive imaging of in vivo tumors by gamma camera scintigraphy after radioiodide or technetium injection has been performed successfully, suggesting that the NIS can serve as an imaging reporter gene for gene therapy trials. In addition, the tumor killing effects of I-131, ReO4-188 and At-211 after NIS gene transfer have been demonstrated in in vitro clonogenic assays and in vivo radioiodide therapy studies, suggesting that NIS gene can also serve as a therapeutic agent when combined with radioiodide injection. Better NIS-mediated imaging and tumor treatment by radioiodide requires a more efficient and specific system of gene delivery with better retention of radioiodide in tumor. Results thus far are, however, promising, and suggest that NIS gene transfer followed by radioiodide treatment will allow non-invasive in vivo imaging to assess the outcome of gene therapy and provide a therapeutic strategy for a variety of human diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.18
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• pp.7617-7623
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• 2014

Objective: The mechanism of action of fatty acid synthase (FASN) in drug tolerance of breast cancer cells with epithelial-mesenchymal transition (EMT) features was investigated. Methods: The breast cancer cell line MCF-7-MEK5 with stably occurring EMT and tumour necrosis factor-${\alpha}$ (TNF-${\alpha}$) tolerance was used as the experimental model, whereas MCF-7 acted as the control. Tumour cells were implanted into nude mice for in vivo analysis, and cerulenin was used as a FASN inhibitor. RT-PCR, real-time quantitative PCR and Western blot were employed to detect the expression of FASN, TNFR-1, TNFR-2, Wnt-1, ${\beta}$-catenin and cytC at the RNA and protein levels. Results: Compared with MCF-7, TNFR-1 expression in MCF-7-MEK5 was slightly changed, TNFR-2 was decreased, and FASN, Wnt-1, ${\beta}$-catenin and cytC were increased. The expression of Wnt-1 and ${\beta}$-catenin in MCF-7-MEK5 decreased after cerulenin treatment, whereas cytC expression increased. Conclusions: The important function of FASN in the drug tolerance of breast cancer may be due to the following mechanisms: FASN downregulated TNFR-2 expression through lipid rafts to make the cells less sensitive to TNF-${\alpha}$, and simultaneously activated the Wnt-$1/{\beta}$-catenin signalling pathway. Thus, cytC expression increased, which provided cells with anti-apoptotic capacity and induced drug tolerance.

• Economic and Environmental Geology
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• v.39 no.4 s.179
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• pp.451-471
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• 2006

Major projects and research topics in the field of rock mechanics are analyzed to obtain the following results: $\cdot$ Rock mechanics deals with the behavior of deformation, failure and displacement of the rock and rock mass on the basis of geological basics. Discontinuities in the rock mass are the most important parameters to control the behavior of rock mass around underground openings. $\cdot$ The objective of site investigation and testing is to determine the strength properties of the rock mass and the in situ stress regime. Specimens for laboratory and in situ tests are to be selected in order that the results of the tests give the representative properties oi the rock mass of the site in question. $\cdot$ The result of a numerical model would be better evaluated not quantitatively but qualitatively. The displacement behavior of the rock mass has to be monitored properly for the NATM (New Austrian Tunneling Method) principles. $\cdot$ The stability of rock slope is to be evaluated preferably by back analysis with strength parameters, such as cohesion and friction angle.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.121-126
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• 2008

Purpose: Poly-N-acetyl glucosamine(PGlcNAc) nanofiber-based materials, produced by a marine microalga, have been characterized as effective hemostatic and angiogenic agents. The similarity between PGlcNAc patch and the natural extracellular matrix allows it to support new healthy tissue growth in an injured area and to encourage fluid absorption. In this study, we hypothesized that a poly-N-acetyl glucosamine fiber patch(PGlcNAc patch) may enhance wound healing in the db/db mouse. Methods: PGlcNAc patches were applied on one square centimeter, full-thickness, skin wounds in the db/db mouse model. Wounds(n=15 per group) were dressed with a PGlcNAc nanofiber patch for 1 hour(1 h), 24 hours(24 h) or left untreated(NT). After the application time, patches were removed and wounds were allowed to heal spontaneously. The rate of wound closure was evaluated by digital analysis of unclosed wound area in course of time. At day 10, wounds(n=7 per group) were harvested and quantified with immunohistochemical markers of proliferation(Ki-67) and vascularization (platelet endothelial cell adhesion molecule, PECAM-1). Results: Wounds dressed with PGlcNAc patches for 1 hour closed faster than control wounds, reaching 90% closure in 16.6 days, nine days faster than untreated wounds. Granulation tissue showed higher levels of proliferation and vascularization following 1 h treatment than the 24 h and NT groups. In addition to its hemostatic properties, the PGlcNAc material also appears to accelerate wound closure in healing-impaired genetically diabetic mice. Conclusion: This material, with its combination of hemostatic and wound healing properties, has the potential to be effective agent for the treatment of complicated wounds.