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Helicobacter Species are Possible Risk Factors of Cholangiocarcinoma

  • Kaewpitoon, Soraya J;Loyd, Ryan A;Rujirakul, Ratana;Panpimanmas, Sukij;Matrakool, Likit;Tongtawee, Taweesak;Kootanavanichpong, Nusorn;Pengsaa, Prasit;Kompor, Ponthip;Chavengkun, Wasugree;Kujapun, Jirawoot;Norkaew, Jun;Ponphimai, Sukanya;Padchasuwan, Natnapa;Polsripradist, Poowadol;Eksanti, Thawatchai;Phatisena, Tanida;Kaewpitoon, Natthawut
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.1
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    • pp.37-44
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    • 2016
  • Several infectious agents are considered to be causes of cancer in human, mainly hepatitis B and C viruses, high-risk human pailloma viruses, Helicobacter pylori, Clonorchis sinensis, and Opisthorchis viverrini. Here we described the evident research and the association between Helicobacter spp. and biliary tract cancer particularly cholangiocarcinoma (CCA). Global epidemiological studies have suggested that Helicobacter spp. are possible risk factors for biliary tract diseases. Molecular studies support a linkage of Helicobacter spp. with CCA development. H. pylori, H. bilis, and H. hepaticus, are found in CCA, but the most common species are H. pylori and H. bilis. The type of CCA are associated with Helicobacter spp. include extrahepatic CCA, and common bile duct cancer. Up to the present, however, the results from different regions, materials and methods, sub-sites of cancer, and controls have not been consistent, thus introducing heterogeneity. Therefore, a comparison between co-Helicobacter spp.-CCA in the countries with low and high incident of CCA is required to settle the question. Furthermore, clarifying variation in the role of Helicobacter species in this CCA, including pathogenesis of CCA through enhanced biliary cell inflammation and proliferation, is necessary.

Gas Separation Study of PEBAX 3533 and PEG Blended Membranes (PEBAX 3533과 PEG의 혼합막에 대한 기체투과 연구)

  • Kim, Kwang Bae;Cho, Eun Hye;Cheong, Seong Ihl;Lee, Hyung Keun;Rhim, Ji Won
    • Membrane Journal
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    • v.23 no.2
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    • pp.144-150
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    • 2013
  • In order to increase the permeabilities of $N_2$, $O_2$, $CH_4$, $CO_2$, $SO_2$, Poly (ether block amides) (PEBAX) 3533 and its blended membranes with Poly (ethylene glycol) (PEG) of molecular weight 400 were prepared. The contents of PEG400 were 20%, 40%, and 50% and this membranes were characterized in terms of permeability for $N_2$, $O_2$, $CH_4$, $CO_2$, $SO_2$ gases and also diffusivity and solubility as well by using the time-lag gas separation apparatus. As expected, the permeabilities incerased as the contents of PEG400 increased. For the ideal selectivity, there is no big difference in values of between PEBAX 3533 and PEBAX/PEG400 membranes. The increase of permeabilities is due to the increases of solubilities of gases in question and this will be explained in more detail.

Comparative analysis of two methods of laser induced boron isotopes separation

  • K.A., Lyakhov;Lee, H.J.
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.407-408
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    • 2011
  • Natural boron consists of two stable isotopes 10B and 11B with natural abundance of 18.8 atom percent of 10B and 81.2 atom percent of 11B. The thermal neutron absorption cross-section for 10B and 11B are 3837 barn and 0.005 barn respectively. 10B enriched specific compounds are used for control rods and as a reactor coolant additives. In this work 2 methods for boron enrichment were analysed: 1) Gas irradiation in static conditions. Dissociation occurs due to multiphoton absorption by specific isotopes in appropriately tuned laser field. IR shifted laser pulses are usually used in combination with increasing the laser intensity also improves selectivity up to some degree. In order to prevent recombination of dissociated molecules BCl3 is mixed with H2S 2) SILARC method. Advantages of this method: a) Gas cooling is helpful to split and shrink boron isotopes absorption bands. In order to achieve better selectivity BCl3 gas has to be substantially rarefied (~0.01%-5%) in mixture with carrier gas. b) Laser intensity is lower than in the first method. Some preliminary calculations of dissociation and recombination with carrier gas molecules energetics for both methods will be demonstrated Boron separation in SILARC method can be represented as multistage process: 1) Mixture of BCl3 with carrier gas is putted in reservoir 2) Gas overcooling due to expansion through Laval nozzle 3) IR multiphoton absorption by gas irradiated by specifically tuned laser field with subsequent gradual gas condensation in outlet chamber It is planned to develop software which includes these stages. This software will rely on the following available software based on quantum molecular dynamics in external quantized field: 1) WavePacket: Each particle is treated semiclassicaly based on Wigner transform method 2) Turbomole: It is based on local density methods like density of functional methods (DFT) and its improvement- coupled clusters approach (CC) to take into account quantum correlation. These models will be used to extract information concerning kinetic coefficients, and their dependence on applied external field. Information on radiative corrections to equation of state induced by laser field which take into account possible phase transition (or crossover?) can be also revealed. This mixed phase equation of state with quantum corrections will be further used in hydrodynamical simulations. Moreover results of these hydrodynamical simulations can be compared with results of CFD calculations. The first reasonable question to ask before starting the CFD simulations is whether turbulent effects are significant or not, and how to model turbulence? The questions of laser beam parameters and outlet chamber geometry which are most optimal to make all gas volume irradiated is also discussed. Relationship between enrichment factor and stagnation pressure and temperature based on experimental data is also reported.

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Development of Practical Problem Based Teaching-Learning Plans and Evaluation of Its Effectiveness on Middle School Students' Self Efficacy, Ego Resilience and Happiness: Focused on the Unit 'Youth's self Management' in Middle School Technology.Home Economics (기술.가정 교과의 중학교 1학년 '청소년의 자기관리' 단원의 실천적 문제중심 가정과 교수-학습 과정안 개발 및 효과검증: 중학생의 자아효능감, 자아탄력성, 행복감 향상에 미치는 효과를 중심으로)

  • Yu, Ji Hye;Lee, Yon Suk
    • Journal of Korean Home Economics Education Association
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    • v.25 no.4
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    • pp.79-98
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    • 2013
  • The purpose of this study was to develop practical problem based teaching-learning plans and to verify its effect on middle school students' self efficacy, ego resilience, and happiness by focusing on the unit of 'Youth's Self Management' in Technology Home Economics. For this study, the contents of twelve different Technology Home Economics middle school textbooks currently in use and a 2007 curriculum guide were analyzed. Based on the problem based question "What do I need to do to control myself better, be mentally healthier, and live a more independent lifestyle?", seven practical problem based teaching-learning plans on 'Youth's Self Management' unit were developed. 7th grade students of "K" middle school living in Gyeonggi province participated in this study. Three control groups were taught through the traditional lecture-based teaching-learning plans while four experimental groups were taught through the practical problem based teaching-learning lesson plans. The effects of lessons on self efficacy, ego resilience and happiness were analyzed using Analysis of Covariance. Significant positive effects on self efficacy, ego resilience and happiness were found in the experimental group of students.

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A Study of Cooperation between Local Libraries and Local Organizations: Focusing on Multicultural Services (공공도서관과 지역사회기관의 협력에 관한 연구 - 다문화 서비스를 중심으로 -)

  • Lim, Yeojoo
    • Journal of the Korean BIBLIA Society for library and Information Science
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    • v.29 no.1
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    • pp.299-324
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    • 2018
  • This study analyzes the processes and the needs of public library services for multicultural populations based on cooperation between public libraries and local organizations. In-depth interviews with public librarians and officers of local organizations were conducted for this case study. Result shows that cooperation was inevitable because there was not enough library personnel compared to the amount of services they have to provide, and the librarians did not have proper skills to serve the diverse populations. Public libraries were cooperating with many local organizations including the Multicultural Family Support Center. Gatekeepers of ethnic communities were playing important roles in promoting and inviting participants for library programs. Many children and young adults with immigration background gained positive views on reading and libraries after participating library programs based on cooperation between public libraries and local organizations, which was recognized as the best achievement of cooperation by many interviewees. Despite many good results of cooperation, how to get to the majority of diverse populations who are not library users yet is still a question mark. Interviewees for this study all agreed that current library service has limitations and insisted a whole new method to invite immigrants and their families to public libraries should be created.

The Analysis on Location and Service Factors Affecting the Management and Use of Judo Gym (유도체육관 운영 및 이용에 영향을 미치는 입지와 서비스 요인 분석)

  • Lee, Do-Heui;Oh, Kyung-Ah
    • Journal of the Korean Applied Science and Technology
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    • v.36 no.2
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    • pp.507-523
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    • 2019
  • This purpose of study was to Analysis on Location and Service Factors Affecting the Management and Use of Judo Gym. This study aims at providing fundamental data and information on Judo coach by studying what effects of location and use factor on trainee satisfaction. The survey was done through 350 copies and excluding 11 copies ran an analysis on the remaining 339(96.8%) copies. After question investigating the data which is collected used IBM SPSS statistics 21 program, frequency analysis, Exploratory factor analysis, Cronbach's ${\alpha}$, correlation analysis, multiple regression. The result of this study were as follows. First, management, location, coach, trainee value, facility, communication in Judo gym location and use factors showed (+) effects on trainee satisfaction. Second, Program operation, Gym quit use, Whether or not to insure in management factor showed (+) effects on trainee satisfaction. Third, Coach credibility in coach factor showed (+) effects on trainee satisfaction. Forth, Member communication in communication factor showed (+) effects on trainee satisfaction. Fifth, Wholesome leisure, Athletic ability improving in trainee value factor showed (+) effects on trainee satisfaction. Sixth, main facility level, additional facility level in facility factor showed (+) effects on trainee satisfaction. Seventh, Visibility in location factor showed (+) effects on trainee satisfaction. And location type(station area, residential district, commercial area) of Judo gym showed (+) effect on management, trainee value, location, communication, facility.

Causal inference from nonrandomized data: key concepts and recent trends (비실험 자료로부터의 인과 추론: 핵심 개념과 최근 동향)

  • Choi, Young-Geun;Yu, Donghyeon
    • The Korean Journal of Applied Statistics
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    • v.32 no.2
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    • pp.173-185
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    • 2019
  • Causal questions are prevalent in scientific research, for example, how effective a treatment was for preventing an infectious disease, how much a policy increased utility, or which advertisement would give the highest click rate for a given customer. Causal inference theory in statistics interprets those questions as inferring the effect of a given intervention (treatment or policy) in the data generating process. Causal inference has been used in medicine, public health, and economics; in addition, it has received recent attention as a tool for data-driven decision making processes. Many recent datasets are observational, rather than experimental, which makes the causal inference theory more complex. This review introduces key concepts and recent trends of statistical causal inference in observational studies. We first introduce the Neyman-Rubin's potential outcome framework to formularize from causal questions to average treatment effects as well as discuss popular methods to estimate treatment effects such as propensity score approaches and regression approaches. For recent trends, we briefly discuss (1) conditional (heterogeneous) treatment effects and machine learning-based approaches, (2) curse of dimensionality on the estimation of treatment effect and its remedies, and (3) Pearl's structural causal model to deal with more complex causal relationships and its connection to the Neyman-Rubin's potential outcome model.

A study on ways of improving of children's self-awareness and self-management competency - focused on values in Confucianism (초등학생들의 자기인식 및 자기관리 능력 함양 방안 연구 - 유학의 가치·덕목을 중심으로 -)

  • Chi, Chun-Ho
    • The Journal of Korean Philosophical History
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    • no.25
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    • pp.41-70
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    • 2009
  • 'Self-awareness' has its core on exactly understanding of your own desire, emotion, value, etc. and then keeping your sense of confidence etc. 'Self-management' has its core on controlling your emotion to overcome stress; suppressing your urge; setting your personal or academic goals and then managing your effort for such goals. This study is to answer the question, "How can we efficiently improve our righteous and good character in the elementary school students?", which is one of the core goals of elementary education. Considering the cultural base of Korea that has the tradition of Confucianism based moral education, Confucian idea that has been verified and accumulated for a long time also shows clearly its own useful value in contemporary moral education. The effort to reorganize such Confucian idea into a character education program and reflect it positively in education, therefore, will be meaningful. Wigijihak (爲己之學: study for yourself) that goes for completeness of moral self, Jungyongjido (中庸之道: positioned in a good balance) that goes for an even life without 'too much and too little' and Hoyeonjigi (浩然之氣: big heart) that encourages moral activeness will contribute largely to realization of 'education for whole person'.

Open Innovation in Car-Sharing Industry: Focusing on the Cooperation Case between Gongcar and Rental Car Company (카셰어링 산업의 개방형 혁신: (주)공카와 렌터카 업체간 개방형 혁신 사례를 중심으로)

  • Kiyeon Hwang;Jaehong Park;Youngwoo Sohn;Woosung Nam;Yeonhwa Cho
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.19 no.1
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    • pp.93-105
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    • 2024
  • Car-sharing is a representative model of the sharing economy, and it is a service that rents or uses a car for the necessary time without owning a car. This industry is growing due to various factors such as technological advances, increasing awareness of environmental protection, and increasing demand for solving traffic congestion problems in cities. Accordingly, there is a need for a strategic approach for companies providing car-sharing services to respond quickly to market changes in order to expand market share and differentiate services. Accordingly, this study conducted a case study on open innovation activities between Gongcar and existing rental car companies, focusing on the research question "What effects do open innovation activities between car-sharing companies and existing rental car companies cause?" As a result of the study, it was confirmed that Gongcar have (1) the ability to actively respond to market fluctuations by establishing a flexible vehicle supply chain based on demand, (2) have significantly reduced growth capital expenditure (Growth Capex), and both cafe and rental car companies have (3) performed successful open innovation by improving key KPI indicators and recording financial performance. This study reveals how open innovation acts as a key business growth engine in the car-sharing industry, and its significance is found in that it empirically confirmed the successful implementation conditions of open innovation based on resource dependence theory.

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Politics through Academic Career or Academic Career for Politics Focused on the current status and conditions of Media scholars' political participation (지식을 통한 정치 혹은 정치를 위한 지식 언론학자의 정치 참여 현황과 특징 연구)

  • Kim, Sung Hae;Seo, Bo Yun;Jin, Min Jung;Kang, Kuk Jin
    • Korean journal of communication and information
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    • v.79
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    • pp.7-39
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    • 2016
  • Journalism and Mass Communication as an academic field is believed more politicized one than pure literature and natural science. With the growth of the media, there follows additional opportunities for media scholars to take a part in politics as well. Few attention was given to understand the status and mechanism of political intervention either as advisers or decision makers though. This study attempts thus to fill this vacuum. For this, first of all, it examines a various types of laws related to media politics. Total number of 164 scholars who participated in 12 councils and commissions were analyzed on the following step. Research shows that there are patterns which favor Seoul National University, U.S. trained Ph. D and geographic preference to the capital. Neither academic excellence nor commitment to public interest appear to have impact on taking those positions. Taking into account media's expansion into politics, it is inevitable for media scholars to take responsibility not only in policy making but in taking leadership. Accordingly, the question of necessity is not who but how as much as manner. The authors hope this study will be a valuable opportunity to establish a kind of ethical standards in media politics.

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