• Title/Summary/Keyword: foreign case study

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Counter-Piracy Cooperation to Strengthen New Southern Policy's "Peace": An Analysis of ROK and ASEAN's Counter-Piracy Practices (신남방정책의 "평화"를 강화하기 위한 해적행위 대응 협력: 한국과 아세안의 해적행위 대응 관행 분석)

  • Boo, Yerin;Kim, Sujin;Yeo, Mathew Jie Sheng
    • Maritime Security
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    • v.3 no.1
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    • pp.141-185
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    • 2021
  • The growing U.S.-China rivalry has placed the countries of Southeast Asia in exceedingly precarious positions. The Republic of Korea (ROK) likewise has been tasked with the challenge of "navigating the waters" between deepening geopolitical divides. It is in this context that the "New Southern Policy" (hereafter NSP) has become a key word in Korea's foreign policy circles. Through NSP, ROK aims to diversify its economic and security interests by strengthening ties with its southern partners, focusing on three key areas (termed as the "3 Ps"): People, Prosperity, and Peace. At the same time, the NSP seeks cooperation with other key diplomatic agendas such as the U.S.'s "Free and Open Indo-Pacific," rendering it crucial for the overall stability of the region. Considering such strategic significance, deeper analysis of the policy is more timely than ever. A brief assessment of the policy's outcome so far, however, reveals that relatively, the "Peace" pillar has been insufficient in achieving satisfactory outcomes. Here, this paper asks the question of: 1) How can the "Peace" pillar of South Korea's New Southern Policy be strengthened? Based on an analysis on the causes of the "Peace" pillar's weakness, this paper identifies counter-piracy cooperation as a solution. This paper then proceeds to answer the next question of: 2) How can ROK and ASEAN cooperate on counter-piracy, and how can these efforts be integrated into ROK's NSP? To answer the above question, this paper conducts in-depth case studies on ASEAN's and ROK's approaches to counter-piracy and identifies specific mechanisms of cooperation. In Chapter I, the paper begins with an overview of the NSP's strategic significance and an evaluation of its "Peace" pillar. Chapter II conducts a literature review on the causes of, and prescriptions for, the weakness of the "Peace" pillar. The paper then justifies why counter-piracy may be a solution. Chapter III examines ASEAN's and ROK's approaches to counter-piracy. By analyzing the general framework and each region's cases, the paper displays the strengths and weaknesses of each region's piracy responses. Based on this analysis, Chapter IV suggests ways to incorporate counter-piracy cooperation into the "Peace" pillar of the NSP. This research bears significance in that it identifies a specific area of cooperation (counter-piracy) to strengthen the "Peace" pillar of ROK's NSP. Such identification is based on a comprehensive study into the two parties' past and current experience in counter-piracy, making it contextual in nature. Furthermore, the study suggests practical mechanisms of cooperation, and considers ways of incorporation into the existing framework of NSP. This approach differs from existing literature that failed to generate case-specific, policy-oriented solutions. The COVID-19 pandemic has exacerbated piracy issues and deepened geopolitical divides. Turbulent seas such as these call for careful navigation. When it comes to promoting "peace," the key lies in combating the pirates that sail those very waters.

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The analysis for attributes of OUV of the capital of Shilla Kingdom (세계유산 신라왕경의 탁월한 보편적 가치 속성 분석)

  • KIM, Euiyeon
    • Korean Journal of Heritage: History & Science
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    • v.55 no.1
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    • pp.151-174
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    • 2022
  • According to the "Special Act on the Restoration and Maintenance of the Core Relics of the Shilla Kingdom" enacted in 2019, the Shilla Kingdom refers to the capital of Shilla and Unified Shilla period, and refers to Gyeongju, where the king lived, and the nearby area. Shilla Wanggyeong is a heritage registered on the UNESCO World Heritage List in 2000 under the name of Gyeongju Historic Site and belongs to Wolseong District, Hwangnyongsa District, and Daeneungwon District among the five districts registered as Gyeongju Historic Site. Unlike the Namsan and Sanseong districts, the Shilla Kingdom is a heritage consisting mostly of archaeological sites without physical substance. Gyeongju City sought to promote local tourism while providing more direct experiences to visitors by restoring the heritage that constitutes the Shilla Kingdom. Starting with the restoration of Woljeonggyo Bridge in 2005, the Shilla Wanggyeong restoration project began in earnest. Gyeongju City tried to restore the building site on the west side of Donggung Palace and Wolji after Woljeonggyo Bridge, but it was canceled due to opposition from the UNESCO World Heritage Committee. The World Heritage Committee opposed the restoration and recommended a heritage impact assessment for similar projects in the future. During the miscarriage impact assessment procedure, there is an OUV attribute analysis process of the heritage to be evaluated. This study intends to preemptively derive OUV attributes for the Silla Kingdom through literature and overseas case analysis. In the case of literature research, domestic and foreign research data related to the UNESCO World Heritage Convention and World Heritage Management were examined, and in overseas cases, the architectural works of Krakow Historical District, Stonehenge and Abbury Geoseok Ruins in England, and Le Corbusier were analyzed. Through this, the outstanding universal value attributes of the Silla Kingdom were derived. This study is expected to be used as a reference in the process of restoration projects of other heritage constituting the Shilla Kingdom or construction plans in nearby areas in the future and serve as an indicator to improve the management system of the Shilla Kingdom more efficiently from the perspective of world heritage.

An Exploratory Study on the Project Performance by PMO Capability (PMO 역량에 따른 프로젝트 성과에 관한 연구)

  • Bae, Jae-Kwon;Kim, Jin-Hwa;Kim, Sang-Yeoul
    • Asia pacific journal of information systems
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    • v.18 no.1
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    • pp.53-77
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    • 2008
  • In recent years, although numbers of corporations are bringing in PMO, they seem to be indifferent to PMO performance measurement. This demonstrates that there are also other reasons beside performance measurement of information systems (IS) project being ambiguous by introducing PMO; the lack of acknowledging the concrete function of PMO, and the scarcity of empirical study about the effect of PMO on the project members and project performance. In this sense, this study is aimed at proposing a new research model in which project success factors (i.e., standardization, management advocacy, and staff expertise) affect PMO capability (i.e., knowledge management, resources management, and problem solving competency) positively, leading to project performance (i.e., task outcomes, psychological outcomes, and organizational outcomes) eventually. To empirically test the research model, data are surveyed from PMO department and IS department. To prove the validity of the proposed research model, PLS analysis is applied with valid 132 questionnaires. By employing PLS technique, the measurement reliability and validity of research variables are tested and the path analysis is conducted to do the hypothesis testing. The path analysis results can be organized into 7 ways in large scale. First, standardization of project success factors has a positive association with knowledge management, resources management, and problem solving competency of PMO capabilities. The findings of this result indicate that the multiple or single project management should satisfy standardization in order to operate an effective PMO. Second, management advocacy of project success factors has a positive association with knowledge management, resources management, and problem solving competency. Management advocacy refers to the willingness of management to provide the required resources and authority for project success. There is agreement among researchers regarding the importance of management advocacy for favorable PMO capability. Third, staff expertise of project success factors has a positive association with knowledge management, resources management, and problem solving competency. The findings of this result indicate that the formation of an exceptional consultant or members with a proficient knowledge for staff expertise of project member is the key factor to elevate the PMO capability. Past research suggests that experience and knowledge and the resultant familiarity with the problem faced can be an important determinant of PMO capability. A capable project with appropriate staff expertise means that it enjoys a diversity of abilities and experiences. Fourth, knowledge management competency of PMO capabilities has a positive impact on psychological outcomes but has no direct effect on task outcomes and organizational outcomes. In domestic case of S. Korea, PMO was finally introduced to many other corporations in 2005 though it started bringing in 2000. Therefore, it had neither a significant impact on the task outcomes nor organizational outcomes by lacking the contents and the infrastructure of the knowledge management because the knowledge consolidation and management period of PMO is comparatively shorter by terms than other foreign nations. Fifth, resources management competency of PMO capabilities has a positive association with task outcomes, psychological outcomes, and organizational outcomes. In addition, problem solving competency of PMO capabilities has a positive association with task outcomes, psychological outcomes, and organizational outcomes. Therefore, the findings of this results stress that PMO capabilities has a positive impact on project performance. Sixth, according to the path analysis of the hypothesis, which suggested in this research, problem solving competency is the PMO capability which is the key success factor for task, psychological, and organizational outcomes as an integrated performance model. Further, the analysis reveals that problem solving competency is an important factor for integrated performance model. The finding is in line with past IS research, which affirms that the work of IS projects is essentially a problem solving endeavor. Seventh, in the path analysis of the hypothesis in this research, the path of the management advocacy $\rightarrow$ problem solving competency $\rightarrow$ organizational outcomes appears to be the most important and strongest path. In brief, the finding of this study suggests that project success factors influence PMO capability positively, and project performance as well. From the results, it can be concluded that PMO helped great improve the project success rate and project performance. This study advances research on PMO capability in three important aspects. First, the findings of our study have implications for IS theory and future research. Our study contributes to IS theory by synthesizing concepts from PMO research and project management research with those in IS research. We proposed and tested PMO capability of IS projects and the findings of our investigation provided some preliminary answers to some of the questions raised. Secondly, this thesis does not only help depicting the concept of IT governance but also approaches empirically. It makes a gradual approach to the main content, step by step, in contrary of simple standard, scholastic way of thinking. Finally, we argued that this task-oriented(technical) view is not sufficient to adequately conceptualize IS project performance. Hence, we applied that the research on organization teams, which provides a flip viewpoint to that of project management research in that it gives more weight for psychological outcomes of organizational work groups, can be very helpful in reconceptualizing the IS project performance construct. The limitations of this study are also discussed to provide research directions for future research.

The Impact of Conflict and Influence Strategies Between Local Korean-Products-Selling Retailers and Wholesalers on Performance in Chinese Electronics Distribution Channels: On Moderating Effects of Relational Quality (중국 가전유통경로에서 한국제품 현지 판매업체와 도매업체간 갈등 및 영향전략이 성과에 미치는 영향: 관계 질의 조절효과)

  • Chun, Dal-Young;Kwon, Joo-Hyung;Lee, Guo-Ming
    • Journal of Distribution Research
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    • v.16 no.3
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    • pp.1-32
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    • 2011
  • I. Introduction: In Chinese electronics industry, the local wholesalers are still dominant but power is rapidly swifting from wholesalers to retailers because in recent foreign big retailers and local mass merchandisers are growing fast. During such transient period, conflicts among channel members emerge important issues. For example, when wholesalers who have more power exercise influence strategies to maintain status, conflicts among manufacturer, wholesaler, and retailer will be intensified. Korean electronics companies in China need differentiated channel strategies by dealing with wholesalers and retailers simultaneously to sell more Korean products in competition with foreign firms. For example, Korean electronics firms should utilize 'guanxi' or relational quality to form long-term relationships with whloesalers instead of power and conflict issues. The major purpose of this study is to investigate the impact of conflict, dependency, and influence strategies between local Korean-products-selling retailers and wholesalers on performance in Chinese electronics distribution channels. In particular, this paper proposes effective distribution strategies for Korean electronics companies in China by analyzing moderating effects of 'Guanxi'. II. Literature Review and Hypotheses: The specific purposes of this study are as follows. First, causes of conflicts between local Korean-products-selling retailers and wholesalers are examined from the perspectives of goal incongruence and role ambiguity and then effects of these causes are found out on perceived conflicts of local retailers. Second, the effects of dependency of local retailers upon wholesalers are investigated on local retailers' perceived conflicts. Third, the effects of non-coercive influence strategies such as information exchange and recommendation and coercive strategies such as threats and legalistic pleas exercised by wholesalers are explored on perceived conflicts by local retailers. Fourth, the effects of level of conflicts perceived by local retailers are verified on local retailers' financial performance and satisfaction. Fifth, moderating effects of relational qualities, say, 'quanxi' between wholesalers and retailers are analyzed on the impact of wholesalers' influence strategies on retailers' performances. Finally, moderating effects of relational qualities are examined on the relationship between conflicts and performance. To accomplish above-mentioned research objectives, Figure 1 and the following research hypotheses are proposed and verified. III. Measurement and Data Analysis: To verify the proposed research model and hypotheses, data were collected from 97 retailers who are selling Korean electronic products located around Central and Southern regions in China. Covariance analysis and moderated regression analysis were employed to validate hypotheses. IV. Conclusion: The following results were drawn using structural equation modeling and hierarchical moderated regression. First, goal incongruence perceived by local retailers significantly affected conflict but role ambiguity did not. Second, consistent with conflict spiral theory, the level of conflict decreased when retailers' dependency increased toward wholesalers. Third, noncoercive influence strategies such as information exchange and recommendation implemented by wholesalers had significant effects on retailers' performance such as sales and satisfaction without conflict. On the other hand, coercive influence strategies such as threat and legalistic plea had insignificant effects on performance in spite of increasing the level of conflict. Fourth, 'guanxi', namely, relational quality between local retailers and wholesalers showed unique effects on performance. In case of noncoercive influence strategies, 'guanxi' did not play a role of moderator. Rather, relational quality and noncoercive influence strategies can serve as independent variables to enhance performance. On the other hand, when 'guanxi' was well built due to mutual trust and commitment, relational quality as a moderator can positively function to improve performance even though hostile, coercive influence strategies were implemented. Fifth, 'guanxi' significantly moderated the effects of conflict on performance. Even if conflict arises, local retailers who form solid relational quality can increase performance by dealing with dysfunctional conflict synergistically compared with low 'quanxi' retailers. In conclusion, this study verified the importance of relational quality via 'quanxi' between local retailers and wholesalers in Chinese electronic industry because relational quality could cross out the adverse effects of coercive influence strategies and conflict on performance.

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A Study on Changes in Habitat Enviroment of Wild Birds in Urban Rivers according to Climate Change - A Case Study of Tancheon Ecological and Landscape Conservation Area - (기후변화에 따른 도시하천의 야생조류 서식환경 변화 연구 - 탄천 생태·경관보전지역를 사례로 -)

  • Han, Jeong-Hyeon;Han, Bong-Ho;Kwak, Jeong-In
    • Journal of the Korean Institute of Landscape Architecture
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    • v.52 no.2
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    • pp.79-95
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    • 2024
  • The purpose of this study was to find the changes in the habitat of wild birds caused by climate change in urban rivers and protected areas that greatly require ecological functions. In the future, this study can be used as a management index to protect the urban river ecosystem and maintain the health of sustainable urban rivers, thereby ensuring biodiversity. The Tancheon Ecological and Landscape Conservation Area, selected as a target site, has been affected by climate change. The four seasons of Korea have a distinct temperate climate, but the average annual temperature in Seoul has risen by 2.4-2.8℃ over the last 40 years. Winter temperatures tended to gradually increase. Precipitation, which was concentrated from June to August, is now changing into localized torrential rain and a uniform precipitation pattern of several months. Climate change causes irregular and unforeseen features. Climate change has been shown to have various effects on urban river ecosystems. The decrease in the area of water surface and sedimentary land impacted river shape change and has led to large-scale terrestrialization. Plants showed disturbance, and the vegetation was simplified. The emergence of national climate change indicator species, the development of foreign herbaceous plants, the change of dry land native herbaceous species, and wet intelligence vegetation were developed. Wild birds appeared in the territory of winter-summer migratory. In addition, species change and the populations of migratory birds also occurred. It was judged that fluctuations in temperature and precipitation and non-predictive characteristics affect the hydrological environment, plant ecology, and wild birds connecting with the river ecosystem. The results of this study were to analyze how climate change affects the habitat of wild birds and to develop a management index for river ecological and landscape conservation areas where environmental and ecological functions in cities operate. This study can serve as a basic study at the level of ecosystem services to improve the health of urban rivers and create a foundation for biodiversity.

A Study on the Correlation between Marine Industry Cluster and Port Regeneration - Focused on the Busan North Port - (해양산업 클러스터와 항만도시재생의 상관성에 관한 연구 - 부산 북항을 중심으로 -)

  • Li, Yun-Zhang;Yang, Ming-Yin;Tian, Xue-Qin;Yu, Yong-Hao;Choi, Tae-Yeong
    • Journal of Korea Port Economic Association
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    • v.38 no.1
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    • pp.101-111
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    • 2022
  • As Asia's leading advanced country, Korea has an absolute advantage over foreign trade routes and maritime economies over inland countries. Following the change in social background, the original port area is for various reasons, and some ills are gradually revealing people's private interests. Due to this, it is the economic interest and future development space of the marine industry cluster in the port area that are directly affected and damaged. This study studied the relationship between marine industry clusters and port urban regeneration. It is intended to present the necessity and importance of activating the marine industry cluster through port urban regeneration while analyzing the regenerative design from the quantitative analysis angle. Therefore, first of all, the theoretical backgrounds were considered, and the cases of port cities that did well worldwide were analyzed according to the current status of the northern port of Busan, the research target site, through analysis. In addition, in order to increase the reliability of this study, the data of marine industry clusters and port city regeneration were reviewed using empirical analysis. Looking at the results of this study's case study and empirical analysis, it is a relationship that actually improved and interacted between the marine industry cluster and the port city regeneration. Through the study, it is expected that the Busan North Port Redevelopment Project will be promoted at the design, environmental, and economic level, and at the same time, it will be able to enhance its status as a marine city in Busan. The results show that, no matter which country or port city, the development of economy, society, culture and will inevitably promote the vigorous development of the marine industrial cluster, also, the port area development to a certain degree. will naturally the physical conditions of regional development obstacle through the port city of regeneration. This promotion will overcome.

Domestic and International Experts' Perception of Policy and Direction on STEAM Education (융합인재교육(STEAM)의 정책과 실행 방향에 대한 국내외 전문가들의 인식)

  • Jung, Jaehwa;Jeon, Jaedon;Lee, Hyonyong
    • Journal of Science Education
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    • v.39 no.3
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    • pp.358-375
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    • 2015
  • The purposes of this study were to investigate the value, necessity and legitimacy of STEAM Education and to propose practical approaching methods for STEAM Education to be applicable in Korea through a variety of literature review, case studies and collecting suggestions from domestic and international educational experts. The research questions are as follows: (1) To investigate the perception, understanding and recognitions of domestic and foreign professionals in STEAM education. (2) To analyze policy implications for an improvement in STEAM. The following aspects of STEAM were found to be challenges in our current STEAM policy after analyzing multiple questionnaires with the professionals and case studies including their experiences, understanding, supports and directions of the policy from the governments. The results indicate that (1) there was a lack of precise and conceptual understanding of STEAM in respect to experience. Training sessions for teachers in this field to help transform their perception is necessary. Development of practical programs with an easy access is also required. It is important to get the aims of related educational activities recognized by the professionals and established standards for an evaluation. The experts perceived that a theme-based learning is the most preferred and effective approaching method and the programs that develop creative thinking and learning applicable to practice are required to promote. (2) The results indicate that there was a lack of programs and inducements for supporting outstanding STEAM educators. It is shown that making an appropriate environment for STEAM education takes the first priority before training numbers of teachers unilaterally, thus securing enough budget seems critical. The professionals also emphasize on developing specialized teaching materials that include diverse inter-related subjects such as science technology, engineering, arts and humanities and social science with diverse viewpoints and advanced technology. This work requires a STEAM network for teachers to link up and share their materials, documents and experiences. It is necessary to get corporations, universities, and research centers participated in the network. (3) With respect to direction, it is necessary to propose policy that makes STEAM education ordinary and more practical in the present education system. The professionals have recommended training sessions that help develop creative thinking and amalgamative problem-solving techniques. They require reducing the workload of teachers and changing teachers' perspectives towards STEAM. They further urge a tight cooperation between departments of the government related with STEAM.

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Renal Anomalies in Children with Turner Syndrome (Turner 증후군 환자에서 신기형에 관한 연구)

  • Kim, Ji Young;Hong, Sun Young;Park, Young Mi;Park, Yong Hoon;Chung, Woo Yeong
    • Clinical and Experimental Pediatrics
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    • v.45 no.7
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    • pp.891-895
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    • 2002
  • Purpose : The prevalence of renal anomalies in Turner syndrome(TS) has been reported to vary from 33% to 60%. The purpose of this study was to clarify the true incidence of renal malformations in Korean TS. Methods : We evaluated 33 patients with Turner syndrome diagnosed by karyotype in Inje University Busan Paik hospital and Youngnam University from January 1995. Intravenous pyelography(IVP) was performed on all patients; abdominal ultrasonography and 99mTc-DMSA renal scan were performed on some. Cytogenetic analysis was performed on all patients with peripheral blood lymphocytes. Results : Of the total 33 patients, the karyotype showed 45, X in 18(54.5%) patients, mosaicism in 11(33.3%) patients and structural aberration in 4(12.2%) patients. The overall incidence of renal anomalies was 36.4%. The renal anomalies included four cases of horeshoe kidney, six cases of abnormal renal collecting system one case of single kidney and one case of malrotation. The incidence of renal anomalies in 45, X karotype(44.4%) showed a higher rate than that of mosaicism and structural aberration(26.7%), but there is no statistical significance. Conclusion : The incidence of renal anomalies in Korean TS reveals 36.4%. This rate is similar to other foreign TS studies. We recommend that renal ultrasonography or IVP for investigation of renal anomalies should be done as a screening procedure for the better quality of life in patients with TS.

Controversial issues in the legal restriction for prenatal genetic testing in Korea (산전검사 대상 질환에 대한 법적 규제의 문제점에 대한 고찰)

  • Choi, Ji-Young;Jeong, Seon-Yong;Kim, Hyon-J.
    • Journal of Genetic Medicine
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    • v.4 no.2
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    • pp.186-189
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    • 2007
  • More than 6,000 rare disorders including genetic diseases have been reported. Of them, 1,500 diseases (1,211 for clinical diagnosis and 289 for research only) are technically possible for genetic testing. In Korea, since 2005, only 63 genetic diseases is permitted for prenatal genetic testing by the "Bioethics and Biosafety Law". The article 25 in the law prescribes 63 genetic diseases without clear indication for its selection and inclusion criteria. In EU, USA, and other foreign countries, however, there is no provision in the statute on prenatal genetic testing; it is not restricted by a law. Recently, a woman (Mrs. L, 38y) who is a carrier for Menkes disease made an appeal to a government for an amendment of the "Bioethics and Biosafety Law" prohibiting the prenatal diagnosis of her pregnancy at risk for Menkes disease. Menkes disease (MNK) is an X-linked recessive disorder characterized by neurodegeneration, connective tissue defects and hair abnormalities, and no effective treatment is available yet. The prevalence rate of MNK is one in about 250,000 live births. Menkes syndrome patients fail to absorb copper from the gastrointestinal tract in quantities adequate for meeting nutritional needs. These needs seem particularly acute during the initial 12 month of life, when the velocity of brain growth and motor neurodevelopment. Most of pts. die around 3yrs. of age. Mrs. L had a boy with Menkes disease who died at 2y.o. in 2001. Subsequent pregnancy in 2003, she was able to have prenatal genetic testing for mutation of the Menkes (ATP7A) gene and delivered a healthy baby boy. Now, She is pregnant again and wants to have prenatal diagnosis. however, this time, she was not allowed to have any more because Menkes disease is not included in 63 genetic diseases permitted by the law for prenatal genetic testing, in spite of the fact that she is a Menkes disease carrier and her pregnancy is at risk to have an affected baby. This case shows the practical problem of the legal restriction for prenatal genetic testing in Korea. In this study, we report a arguable case and discuss the controversial issues in the legal restriction for prenatal genetic testing in Korea.

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Effects Of Cultured Bone Cell On The Regeneration Of Alveolar Bone (배양골세포 이식이 치조골재생에 미치는 영향)

  • Jeong, Soon-Joon;Herr, Yeek;Park, Joon-Bong;Lee, Man-Sup;Kwon, Young-Hyuk
    • Journal of Periodontal and Implant Science
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    • v.26 no.1
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    • pp.1-26
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    • 1996
  • This study was performed to estimate the effects of cultured bone cell inoculated on porous type hydroxyaptite for the regeneration of the artificial alveolar bone defect. In this experiment 3 beagle dogs were used, and each of them were divided into right and left mandible. Every surgical intervention were performed under the general anesthesia by using with intravenous injection of Pentobarbital sodium(30mg/Kg). To reduce the gingival bleeding during surgery, operative site was injected with Lidocaine hydrochloride(l:80,000 Epinephrine) as local anesthesia. After surgery experimental animal were feeded with soft dietl Mighty dog, Frisies Co., U.S.A.) for 1 weeks to avoid irritaion to soft tissue by food. 2 months before surgery both side of mandibular 1st premolar were extracted and bone chips from mandibular body were obtained from all animals. Bone cells were cultured from bone chips obtained from mandible with Dulbecco's Modified Essential Medium contained with 10% Fetal Bovine Serum under the conventional conditions. Porous type hydroxyapatite were immerse into the high concentrated cell suspension solution, and put 4 hours for attachin the cells on the surface of hydroxyapatite. Graft material were inserted on the artificial bone defect after 3 days of culture. Before insertion of cellinoculated graft material, scanning electronic microscopic observation were performed to confirm the attachment and spreading of cell on the hydroxyapatite surface. 3 artificial bone defects were made with bone trephine drill on the both side of mandible of the experimental animal. First defect was designed without insertion of graft material as negative control, second was filled with porous replamineform hydroxyapatite inoculated with cultured bone marrow cells as expermiental site, and third was filled with graft materials only as positive control. The size of every artificial bone defect was 3mm in diameter and 3mm in depth. After the every surgical intervention of animals, oral hygiene program were performed with 1.0% chlorhexidine digluconate. All of the animals were sacrificed at 2, 4, 6 weeks after surgery. For obtaining histological section, tissus were fixed in 10% Buffered formalin and decalcified with Planko - Rycho Solution for 72hr. Tissue embeding was performed in paraffin and cut parallel to the surface of mandibular body. Section in 8um thickness of tissue was done and stained with Hematoxylin - Eosin. All the specimens were observed under the light microscopy. The following results were obtained : 1. In the case of control site which has no graft material, less inflammatory cell infiltration and rapid new bone forming tendency were revealed compared with experimental groups. But bone surface were observed depression pattern on defect area because of soft tissue invasion into the artificial bone defect during the experimental period. 2. In the porous hydroxyapatite only group, inflammatory cell infiltration was prominet and dense connective tissue were encapsulated around grafted materials. osteoblastic activity in the early stage after surgery was low to compared with grafted with bone cells. 3. In the case of porous hydroxyapatite inoculated with bone cell, less inflammatory cell infiltration and rapid new bone formation activity was revealed than hydroxyapatite only group. Active new bone formation were observed in the early stage of control group. 4. The origin of new bone forming was revealed not from the center of defected area but from the surface of preexisting bony wall on every specimen. 5. In this experiment, osteoclastic cell was not found around grafted materials, and fibrovascular invasion into regions with no noticeable foreign body reaction. Conclusively, the cultured bone cell inoculated onto the porous hydroxyapatite may have an important role of regeneration of artificial bone defects of alveolar bone.

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