• Title/Summary/Keyword: Human Model

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Regulatory Mechanism of Radiation-induced Cancer Cell Death by the Change of Cell Cycle (세포주기 변화에 타른 방사선 유도 암세포 사망의 조절기전)

  • Jeong Soo-Jin;Jeong Min-Ho;Jang Ji-Yeon;Jo Wol-Soon;Nam Byung-Hyouk;Jeong Min-Za;Lim Young-Jin;Jang Byung Gon;Youn Seon-Min;Lee Hyung Sik;Hur Won Joo;Yang Kwang Mo
    • Radiation Oncology Journal
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    • v.21 no.4
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    • pp.306-314
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    • 2003
  • Purpose : In our Previous study, we have shown the main cel1 death pattern Induced by irradiation or protein tyrosine kinase (PTK) inhibitors in K562 human myeiogenous leukemic cell line. Death of the cells treated with irradiation alone was characterized by mitotic catastrophe and typical radiation-induced apoptosis was accelerated by herblmycin A (HMA). Both types of cell death were inhibited by genistein. In this study, we investigated the effects of HMA and genistein on cell cycle regulation and its correlation with the alterations of radiation-induced cell death. Materials and Methods: K562 cells In exponential growth phase were used for this study. The cells were Irradiated with 10 Gy using 6 MeV Linac (200-300 cGy/min). Immediately after irradiation, cells were treated with 250 nM of HMA or 25 $\mu$N of genistein. The distributions of cell cycle, the expressions of cell cycle-related protein, the activities of cyclin-dependent kinase, and the yield of senescence and differentiation were analyzed. Results: X-irradiated cells were arrested In the G2 phase of the cell cycle but unlike the p53-positive cells, they were not able to sustain the cell cycle arrest. An accumulation of cells in G2 phase of first ceil-cycle post-treatment and an increase of cyclin Bl were correlated with spontaneous, premature, chromosome condensation and mitotic catastrophe. HMA induced rapid G2 checkpoint abrogation and concomitant p53-independent Gl accumulation. HMA-induced cell cycle modifications correlated with the increase of CDK2 kinase activity, the decrease of the expressions of cyclins I and A and of CDK2 kinase activity, and the enhancement of radiation-induced apoptosis. Genistein maintained cells that were arrested in the G2-phase, decreased the expressions of cyclin Bl and cdc25c and cdc25C kinase activity, increased the expression of pl6, and sustained senescence and megakaryocytic differentiation. Conclusion: The effects of HMA and genistein on the radiation-induced cell death of KS62 cells were closely related to the cell cycle regulatory activities. In this study, we present a unique and reproducible model in which for investigating the mechanisms of various, radiation-induced, cancer cell death patterns. Further evaluation by using this model will provide a potent target for a new strategy of radiotherapy.

Organizational Factors Facilitating the Internationalization of Korean Franchising Companies (해외진출 국내 프랜차이즈기업의 조직특성)

  • Lim, Young-Kun;Lee, Dong-Whuy;Kim, Hee-Jung
    • Journal of Global Scholars of Marketing Science
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    • v.19 no.2
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    • pp.40-52
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    • 2009
  • Franchising is one of the fastest growing types of business. It is already popular and well-known in the U.S., and has been growing in many other countries including Korea. Furthermore, many Korean franchising companies have expanded their business overseas actively. According to the data by the Ministry of Industry and Resource, 82 companies out of a sample of 500 franchising companies are already operating in many foreign countries and 48% of them have started their foreign business since 2006. This clearly indicates the fast growing current trend of foreign operation by Korean franchising companies. In spite of the fast growing trend of foreign expansion in the industry, academic research on internationalization of franchising companies is extremely difficult to find. Accordingly, academic research on the issue is necessary and urgent in Korea. Among the various research questions on internationalization of franchising business, this study intends to investigate the difference in organizational factors between the franchising companies doing foreign operation and those doing business only domestically. More specifically, this research has the following purposes. First, considering the lack of theoretical basis of previous studies, resource-based theory and agency theory are employed as the theoretical bases. Second, this study explains the difference in internationalization based on organizational factors such as company size, history and growth rate. Third, the five hypotheses regarding the difference in organizational factors are presented and tested empirically, which is the first attempt in the area of this topic. Finally, the study attempts to clarify the conflicting implications among theories regarding some organizational factos such as growth rate. As the theoretical background, resource-based theory and agency theory are discussed. According to resource-based theory, a firm can grow continuously when it has competence and resource, and also the ability to develop them. The competence and resource can include capital, human resource, management skill, market information, ability to manage risk, etc. Meanwhile, agency theory views the relationship between franchisor and franchisee as an agency relationship. In agency theory, bonding capability and monitoring capability are the two key factors which promote internationalization of franchising companies. Based on the two theories, a conceptual model is designed. The model consists of two groups of variables. One is organizational factors including size, history, growth rate, price bonding and geographic dispersion. The other is whether a franchising company is operating overseas or not. We developed the following five research hypotheses basically describing the relationship between organizational factors and internationalization of franchising companies. H1: The size of franchising companies operating overseas is larger than that of franchising companies operating domestically. H2: The history of franchising companies operating overseas is longer than that of franchising companies operating domestically. H3: The growth rate of franchising companies operating overseas is higher than that of franchising companies operating domestically. H4: The price bonding of franchising companies operating overseas is higher than that of franchising companies operating domestically. H5: The geographic dispersion of franchising companies operating overseas is wider than that of franchising companies operating domestically. Data for the analyses are obtained from 2005 Korea Franchise Survey data co-generated by Ministry of Industry and Resource, GS1 Korea, and Korea Franchise Association. Out of 2,804 population companies, 2,489 companies are excluded for various reasons and 315 companies are selected as the final sample. Prior to hypotheses tests, validity and reliability of the measures of size, history, growth rate and price bonding are examined for further analyses. Geographic dispersion is not validated since it is measured using nominal data. A series of independent sample T-tests is used to find out whether there exists any significant difference between the companies internationalized and those operating only domestically for each organizational factor. Among the five factors, size and geographic dispersion show significant difference, growth rate and price bonding do not reveal any difference and, finally, history factor shows conflicting results in the difference depending on how to measure it.

    shows the summary statistics for hypotheses testing. In conclusion, the results show that the size and history, which are the key variables in resource-based theory, have a significant relationship with internationalization and that geographic area, which belongs to agency theory, also has a strong relationship with internationalization. The results support the findings of extant research and, therefore, prove the usefulness of resource-based theory and agency theory in explaining internationalization of franchising companies. However, growth rate and price-bonding do not show a clear difference between the two types of companies. Accordingly, these two factors need further attention in the future research. Although this study shows meaningful findings theoretically and practically, it has several limitations. First, only organizational factors are considered even if there are various environmental factors influencing franchising firm's internationalization. Second, only being internationalized or not is considered. That is, modes of entry and the size of foreign operations are not included in the study. Third, internationalization strategy is often determined based on the desire for business expansion and higher profitability and egoistical reasons of the CEOs. However, this type of factors belonging to behavioral science is not discussed in the study. Finally, organizational ecology perspective is usefully applicable in explaining the survival and performance of internationally operating companies. Accordingly, research propositions based on this perspective need to be developed and tested.

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  • The Strategy for the Environmental Education through the Practical Arts(TechnologyㆍHome economics) Subject in a viewpoint of the Clothing & Textiles resources (의생활자원 관점에서의 실과(기술ㆍ가정) 환경교육방안에 관한 연구)

    • Chung Mee-Kyung
      • Journal of Korean Home Economics Education Association
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      • v.16 no.3
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      • pp.131-146
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      • 2004
    • The Purpose of this study is to suggest strategies for environmental education through the Practical Arts(TechnologyㆍHome economics) Subject in a viewpoint of the clothing & textiles resources to resolve problems in the clothing life area. For this, this study was carried out through review of literature which is related with the consumption, the environmental problems, the environmental policies, and regulations of the government and new environmental technologies, of clothing & textiles industries and environmental education. The major findings of the study were as follows; 1) The environmental education system model in a viewpoint of the Clothing & Textiles resources was developed. This model system is consisted with interactions on school, government, industry, home and non-government organizations. Thus, the fact that Practical Arts(TechnologyㆍHome economics) Subject were the most effective subject to teaching the environmental education viewpoint of the Clothing & Textiles resources was confirmed. 2) The standards were analysed out to analyse the contents in the clothing area of the Practical Arts(TechnologyㆍHome economics) Subject. It were consist of 4 factors and 12 elements under the factors: Awareness of clothing & textile resources(clothing consumption, production of clothing & textile and environmental problems). Planning and buying of clothing(planning, buying), Management of clothing(understand of textile. human body & environment, laundering and Environmental pollution, arrangement & conservation) Recycling & exhaust of clothing(contribution, redesign, recycling, exhaust) 3) Analysing the current Practical Arts (TechnologyㆍHome economics) subject from the Environmental education in the clothing section, the environmental education related with clothing were taught the most in the middle school course, and environmental contents were concentrated in the recycling factors. but not so much on other factors. 4) After analysing the Practical Arts (TechnologyㆍHome economics) subject, the strategies were suggested for reinforcing the environmental education in the clothing of the Practical Arts(TechnologyㆍHome economics) subject.

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    The Effects of Psychological Contract Violation on OS User's Betrayal Behaviors: Window XP Technical Support Ending Case (심리적 계약 위반이 OS이용자의 배신 행동에 미치는 영향: 윈도우 XP 기술적 지원서비스 중단 사례)

    • Lee, Un-Kon
      • Asia pacific journal of information systems
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      • v.24 no.3
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      • pp.325-344
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      • 2014
    • Technical support of Window XP ended in March, 8, 2014, and it makes OS(Operating System) users fall in a state of confusion. Sudden decision making of OS upgrade and replacement is not a simple problem. Firms need to change the long term capacity plan in enterprise IS management, but they are pressed for time and cost to complete it. Individuals can not help selecting the second best plan, because the following OSs of Window XP are below expectations in performances, new PC sales as the opportunities of OS upgrade decrease, and the potential risk of OS technical support ending had not announced to OS users at the point of purchase. Microsoft as the OS vendors had not presented precaution or remedy for this confusion. Rather, Microsoft announced that the technical support of the other following OSs of Wndow XP such as Window 7 would ended in two years. This conflict between OS vendor and OS users could not happen in one time, but could recur in recent future. Although studies on the ways of OS user protection policy would be needed to escape from this conflict, few prior studies had conducted this issue. This study had challenge to cautiously investigate in such OS user's reactions as the confirmation with OS user's expectation in the point of purchase, three types of justice perception on the treatment of OS vendor, psychological contract violation, satisfaction and the other betrayal behavioral intention in the case of Window XP technical support ending. By adopting the justice perception on this research, and by empirically validating the impact on OS user's reactions, I could suggest the direction of establishing OS user protection policy of OS vendor. Based on the expectation-confirmation theory, the theory of justice, literatures about psychological contract violation, and studies about consumer betrayal behaviors in the perspective of Herzberg(1968)'s dual factor theory, I developed the research model and hypothesis. Expectation-confirmation theory explain that consumers had expectation on the performance of product in the point of sale, and they could satisfied with their purchase behaviors, when the expectation could have confirmed in the point of consumption. The theory of justice in social exchange argues that treatee could be willing to accept the treatment by treater when the three types of justice as distributive, procedural, and interactional justice could be established in treatment. Literatures about psychological contract violation in human behaviors explains that contracter in a side could have the implied contract (also called 'psychological contract') which the contracter in the other side would sincerely execute the contract, and that they are willing to do vengeance behaviors when their contract had unfairly been broken. When the psychological contract of consumers had been broken, consumers feel distrust with the vendors and are willing to decrease such beneficial attitude and behavior as satisfaction, loyalty and repurchase intention. At the same time, consumers feel betrayal and are willing to increase such retributive attitude and behavior as negative word-of-mouth, complain to the vendors, complain to the third parties for consumer protection. We conducted a scenario survey in order to validate our research model at March, 2013, when is the point of news released firstly and when is the point of one year before the acture Window XP technical support ending. We collected the valid data from 238 voluntary participants who are the OS users but had not yet exposed the news of Window OSs technical support ending schedule. The subject had been allocated into two groups and one of two groups had been exposed this news. The data had been analyzed by the MANOVA and PLS. MANOVA results indicate that the OSs technical support ending could significantly decrease all three types of justice perception. PLS results indicated that it could significantly increase psychological contract violation and that this increased psychological contract violation could significantly reduce the trust and increase the perceived betrayal. Then, it could significantly reduce satisfaction, loyalty, and repurchase intention, and it also could significantly increase negative word-of-month intention, complain to the vendor intention, and complain to the third party intention. All hypothesis had been significantly approved. Consequently, OS users feel that the OSs technical support ending is not natural value added service ending, but the violation of the core OS purchase contract, that it could be the posteriori prohibition of OS user's OS usage right, and that it could induce the psychological contract violation of OS users. This study would contributions to introduce the psychological contract violation of the OS users from the OSs technical support ending in IS field, to introduce three types of justice as the antecedents of psychological contract violation, and to empirically validate the impact of psychological contract violation both on the beneficial and retributive behavioral intentions of OS users. For practice, the results of this study could contribute to make more comprehensive OS user protection policy and consumer relationship management practices of OS vendor.

    Accessibility Analysis in Mapping Cultural Ecosystem Service of Namyangju-si (접근성 개념을 적용한 문화서비스 평가 -남양주시를 대상으로-)

    • Jun, Baysok;Kang, Wanmo;Lee, Jaehyuck;Kim, Sunghoon;Kim, Byeori;Kim, Ilkwon;Lee, Jooeun;Kwon, Hyuksoo
      • Journal of Environmental Impact Assessment
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      • v.27 no.4
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      • pp.367-377
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      • 2018
    • A cultural ecosystem service(CES), which is non-material benefit that human gains from ecosystem, has been recently further recognized as gross national income increases. Previous researches proposed to quantify the value of CES, which still remains as a challenging issue today due to its social and cultural subjectivity. This study proposes new way of assessing CES which is called Cultural Service Opportunity Spectrum(CSOS). CSOS is accessibility based CES assessment methodology for regional scale and it is designed to be applicable for any regions in Korea for supporting decision making process. CSOS employed public spatial data which are road network and population density map. In addition, the results of 'Rapid Assessment of Natural Assets' implemented by National Institute of Ecology, Korea were used as a complementary data. CSOS was applied to Namyangju-si and the methodology resulted in revealing specific areas with great accessibility to 'Natural Assets' in the region. Based on the results, the advantages and limitations of the methodology were discussed with regard to weighting three main factors and in contrast to Scenic Quality model and Recreation model of InVEST which have been commonly used for assessing CES today due to its convenience today.

    Effects of Whey Protein Hydrolysates on Lipid Profiles and Appetite-Related Hormones in Rats Fed High Fat Diet (고지방식이를 섭취한 흰쥐에서 유청단백질 가수분해물의 섭취가 지질 농도 및 식욕 관련 호르몬에 미치는 영향)

    • Park, Jung-Yoon;Park, Mi-Na;Choi, You-Young;Yun, Sung-Seob;Chun, Ho-Nam;Lee, Yeon-Sook
      • Journal of the Korean Society of Food Science and Nutrition
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      • v.37 no.4
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      • pp.428-436
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      • 2008
    • This study was carried out to compare the effects of whey protein concentrate, its hydrolysates and macropeptide fractions obtained from papain treatment of whey protein on lipid levels and appetite-related hormones in obesity model rats induced by high fat diet. Four week-old male Sprague-Dawley rats were fed high fat (18% w/w) and low protein (10% w/w) diet for 4 weeks and then divided into four groups (n=8/group). Rats were fed high fat diets containing various nitrogen sources; 10% whey protein concentrate (10WPC), 25% whey protein concentrate (25WPC), 25% whey protein hydrolysates (25WH), and 25% whey macropeptide fractions (25WP, MW$\geq$10,000), respectively for 6 weeks. There were no significant differences in body weight gain and food intake among groups. A significant decrease of total lipid, triglyceride in serum was observed in 25WH and 25WP groups. Total lipid and triglyceride contents of the liver were significantly decreased in 25WPC, 25WH and 25WP groups compared with 10WPC group. However, in the liver, there were no differences in the contents of total lipid and triglyceride among 25WPC, 25WH and 25WP groups. The daily amounts of feces were significantly increased in 25WH and 25WP groups and the excretion of total lipid and triglyceride were significantly increased in 25WH group. Serum glucose and insulin concentration were significantly decreased in 25WH group. The concentration of serum ghrelin was significantly decreased in the 25WPC, 25WH and 25WP groups compared with 10WPC group. However, there was no significant difference in the concentration of serum leptin among groups. These results suggest that whey protein hydrolysates and macropeptide fractions may show beneficial effects on the lipid profile in serum and liver, appetite regulation and insulin resistance in obesity model rats induced by high fat diet.

    Effect of n-3 Fatty Acid Deficiency on Fatty Acid Composition in Brain, Retina and Liver Using a Novel Artificial Rearing System (인공 사육 동물 모델 시스템을 이용한 n-3 지방산 결핍이 쥐의 뇌, 망막, 간의 지방산 조성에 미치는 영향)

    • Lim, Sun-Young
      • Journal of the Korean Society of Food Science and Nutrition
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      • v.34 no.4
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      • pp.466-475
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      • 2005
    • Docosahexaenoic acid (22:6n-3, DHA) is highly enriched in membrane of brain and retina, and plays an important role in maintaining an optimal function of the central nervous system. We investigated the effect of n-3 fatty acid deficiency on rat brain, retina and liver fatty acyl composition at two different ages (3 wks and 15 wks) under DHA deficient condition. Rat pups born to dams fed a diet with $3.1\%$ of total fatty acids as $\alpha-linolenic$ acid (LNA) were fed using an artificial rearing system either an n-3 deficient (n-3 Def) or n-3 adequate (n-3 Adq) diet. Both diets contained $17.1\%$ linoleic acid (LA) but the n-3 Adq diet also contained $3.1\%$ LNA. Rats consuming the n-3 Def diet showed a lower brain $(50\%\;in\;13\;wks\;and\;70\%\;in\;15\;wks,\;p<0.05)$ and retinal $(50\%\;in\;13\;wks\;and\;63\%\;in\;15\;wks,\;p<0.05)$ DHA than those on the n-3 Adq diet, which was largely compensated for by an increase in docosapentaenoic acid (22:5n-6, DPAn-6). In the liver of the n-3 Def group, the percentage of DHA decreased by $97\%$ at 3 wks of age with an apparent increase in DPAn-6 relative to the n-3 Adq group (p<0.05), while there was a $65\%$ lower liver DHA in n-3 Def group at 15 wks of age than the n-3 Adq group (p<0.05). Liver arachidonic acid (20:4n-6, AA) was increased at 3 wks of age but decreased at 15 wks of age in the n-3 Def group compared with n-3 Adq group (p<0.05). In conclusion, the replacement of DHA by DPAn-6 in brain and retina fatty acid composition may be related to the suboptimal function in spatial learning, memory and visual acuity. This artificial rearing method presents a first generation model for n-3 deficiency that is similar to the case of human nutrition that commonly employed two generation model.

    Characterization of a Mucolipidosis Type II Mouse Model and Therapeutic Implication of Lysosomal Enzyme Enriched Fraction Derived from Placenta (뮤코지방증 2형 마우스 모델의 특징과 태반에서 추출한 리소좀 효소 투여의 결과)

    • Cho, Sung Yoon;Kim, Ki-Yong;Kim, Su Jin;Sohn, Young Bae;Maeng, Se Hyun;Kim, Chi Hwa;Ko, Ah-Ra;Song, Junghan;Yeau, Sung-Hee;Kim, Kyung-Hyo;Jin, Dong-Kyu
      • Journal of The Korean Society of Inherited Metabolic disease
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      • v.12 no.1
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      • pp.5-13
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      • 2012
    • I-cell disease (mucolipidosis type II; MIM 252500) and pseudo-Hurler polydystrophy (mucolipidosis type III; MIM 252600) are disorders caused by abnormal lysosomal transport in cells. The presence of numerous inclusion bodies in the cytoplasm of fibroblasts, a lack of mucopolysacchariduria, increased lysosomal enzyme activity in serum, and decreased GlcNAc-phosphotransferase activity are hallmark. Here, we attempted to investigate phenotypical and biochemical characteristics of the knockoutmouse of GlcNAc-phosphotransferase ${\alpha}/{\beta}$ subunits; in addition, we also attempted to determine whether the lysosome enriched fraction derived from placenta can be beneficial to phenotype and biochemistry of the knockout mouse.We found that the knockout mouse failed to thrive and had low bone density, as is the case in human. In addition, skin fibroblasts from the animal had the same biochemical characteristics, including increased lysosomal enzyme activity in the culture media, in contrast to the relatively low enzyme activity within the cells. Intravenous injection of the lysosome rich fraction derived from placenta into the tail vein of the animal resulted in a gain of weight, while saline injected animals didn't.In conclusion, our study demonstrated the phenotypical and biochemical similarities of the knockout mouse to a mucolipidosis type II patient and showed the therapeutic potential of the lysosome enriched fraction. We admit that a larger scale animal study will be needed; however, the disease model and the therapeutic potential of the lysosome enriched fraction will highlight the hope for a novel treatment approach to mucopolipidosis type II, for which no therapeutic modality is available.

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    Technical Efficiency of Medical Resource Supply and Demand (의료자원 공급, 수요의 성과 효율성에 대한 실증분석)

    • Chang, Insu;Ahn, Hyeong Seok;Kim, Brian H.S.
      • Journal of the Korean Regional Science Association
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      • v.34 no.2
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      • pp.3-19
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      • 2018
    • The objective of this study is to observe the efficiency of clinical performance on the supply and demand of medical resources in Korea. For the empirical analysis, we constructed the dataset on age standardized mortality rate, the number of physician, specialist, surgery, medical institution, ratio of general hospitals of 16 provinces in Korea from 2006 to 2013. The panel probability frontier model is employed as an analysis method and considered heteroscedasticity and autocorrelation of the error in panel data. In addition, the demographic and socioeconomic characteristics of the 16 provinces, unemployment rate, elderly population ratio, GRDP per capita, and ratio of hospitals in comparison to the general hospitals are used to find the effect on the technical efficiency of clinical performance on supply and demand of medical resources. The results are as follows. First, for the clinical performance, the supply side of human resources such as doctors and specialists and the demand side factors such as chronic illness clinic per unit population have a significant influence, respectively. Second, the technical efficiency of clinical performance on the supply and demand of medical resources of each input component was 59-70% in terms of clinical efficiency in each region. Third. estimates of technical efficiency of inputs that affect clinical performance showed a slight increase in all regions during the analysis period, but the increase trend decreased slightly. Fourth, the ratio of the elderly population and GRDP per capita have a positive influence on the technical efficiency of clinical performance on the supply and demand of medical resources. The difference of each efficiency by region is due to the regional differences of the input medical resources and the combination of them and the demographic and socioeconomic characteristics of the region. It is understood that the differences in technological efficiency due to the complexity of supply and demand of medical resources, demographic structure and economic difference affecting clinical performance by region are different.

    Computer Aided Diagnosis System for Evaluation of Mechanical Artificial Valve (기계식 인공판막 상태 평가를 위한 컴퓨터 보조진단 시스템)

    • 이혁수
      • Journal of Biomedical Engineering Research
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      • v.25 no.5
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      • pp.421-430
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      • 2004
    • Clinically, it is almost impossible for a physician to distinguish subtle changes of frequency spectrum by using a stethoscope alone especially in the early stage of thrombus formation. Considering that reliability of mechanical valve is paramount because the failure might end up with patient death, early detection of valve thrombus using noninvasive technique is important. Thus the study was designed to provide a tool for early noninvasive detection of valve thrombus by observing shift of frequency spectrum of acoustic signals with computer aid diagnosis system. A thrombus model was constructed on commercialized mechanical valves using polyurethane or silicon. Polyurethane coating was made on the valve surface, and silicon coating on the sewing ring of the valve. To simulate pannus formation, which is fibrous tissue overgrowth obstructing the valve orifice, the degree of silicone coating on the sewing ring varied from 20%, 40%, 60% of orifice obstruction. In experiment system, acoustic signals from the valve were measured using microphone and amplifier. The microphone was attached to a coupler to remove environmental noise. Acoustic signals were sampled by an AID converter, frequency spectrum was obtained by the algorithm of spectral analysis. To quantitatively distinguish the frequency peak of the normal valve from that of the thrombosed valves, analysis using a neural network was employed. A return map was applied to evaluate continuous monitoring of valve motion cycle. The in-vivo data also obtained from animals with mechanical valves in circulatory devices as well as patients with mechanical valve replacement for 1 year or longer before. Each spectrum wave showed a primary and secondary peak. The secondary peak showed changes according to the thrombus model. In the mock as well as the animal study, both spectral analysis and 3-layer neural network could differentiate the normal valves from thrombosed valves. In the human study, one of 10 patients showed shift of frequency spectrum, however the presence of valve thrombus was yet to be determined. Conclusively, acoustic signal measurement can be of suggestive as a noninvasive diagnostic tool in early detection of mechanical valve thrombosis.


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