• Title/Summary/Keyword: Review Features

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Functional Enhancers As Master Regulators of Tissue-Specific Gene Regulation and Cancer Development

  • Ko, Je Yeong;Oh, Sumin;Yoo, Kyung Hyun
    • Molecules and Cells
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    • v.40 no.3
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    • pp.169-177
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    • 2017
  • Tissue-specific transcription is critical for normal development, and abnormalities causing undesirable gene expression may lead to diseases such as cancer. Such highly organized transcription is controlled by enhancers with specific DNA sequences recognized by transcription factors. Enhancers are associated with chromatin modifications that are distinct epigenetic features in a tissue-specific manner. Recently, super-enhancers comprising enhancer clusters co-occupied by lineage-specific factors have been identified in diverse cell types such as adipocytes, hair follicle stem cells, and mammary epithelial cells. In addition, noncoding RNAs, named eRNAs, are synthesized at super-enhancer regions before their target genes are transcribed. Many functional studies revealed that super-enhancers and eRNAs are essential for the regulation of tissue-specific gene expression. In this review, we summarize recent findings concerning enhancer function in tissue-specific gene regulation and cancer development.

Carbon Doping of TiO2 for Visible Light Photo Catalysis - A review

  • Palanivelu, K.;Im, Ji-Sun;Lee, Young-Seak
    • Carbon letters
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    • v.8 no.3
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    • pp.214-224
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    • 2007
  • The field of photocatalysis is one of the fastest growing areas both in research and commercial fields. Titanium dioxide is the most investigated semi-conductor material for the photocatalysis applications. Research to achieve $TiO_2$ visible light activation has drawn enormous attentions because of its potential to use solar light. This paper reviews the attempts made to extend its visible photocatalytic activity by carbon doping. Various approaches adopted to incorporate carbon to $TiO_2$ are summarized highlighting the major developments in this active research field. Theoretical features on carbon doping are also presented. Future scenario in the rapidly developing and exciting area is outlined for practical applications with solar light.

An Empirical Study on the Critical Factors for Successful m-Learning Implementation (성공적인 m-Learning 구현을 위한 핵심 요인에 대한 연구)

  • Whang, Jae-Hoon;Kim, Dong-Hyun
    • Journal of Information Technology Applications and Management
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    • v.12 no.3
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    • pp.57-80
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    • 2005
  • This study defined the notion of general idea on m-learning as based upon e-Learning and mobile internet related literature review and identified the m-Learning distinctive features. Also, this study has searched for factors that are expected to influence the use intended for m-Learning from self-regulated learning, which is acknowledged to be a useful method for learning accomplishment in education field, in order to measure the relationship between learners' motivation and use intention. Then it has empirically validated the conceptual model based on Davis' TAM (Technology Acceptance Model) As a result, self-efficacy, self-determination, interest, contents quality, time management, help seeking, and Peer study are factors affecting Perceived usefulness. Also self-efficacy, self-determination, interest, contents qualify, time management, and peer study are factors affecting perceived ease of use. Finally both perceived usefulness and perceived ease of use are significant factors affecting use intention.

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Miniaturization of Polymerase Chain Reaction

  • Lee, Ji-Youn;Kim, Jae-Jeong;Park, Tai-Hyun
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.8 no.4
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    • pp.213-220
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    • 2003
  • Polymerase chain reaction (PCR) is one of the most widely used analytical tool and is an important module that would benefit from being miniaturized and integrated onto diagnostic or analytical chips. There are potentially two different approaches for the miniaturization of the PCR module: chamber-type and flow-type micro-PCR. These miniaturized PCRs have distinct characteristics and advantages. In this article, we review the necessity of micro-PCR, the materials for the chip fabrication, the surface modification, and characteristics of the two types of micro-PCR. The motivation underlying the development of micro-PCR, the advantages and disadvantages of the various materials used in fabrication and the surface modification methods will be discussed. And finally, the precise features of the two different types of micro-PCR will be compared.

Recognition and Treatment of Anxiety in Medically Ill Patients (신체질환에서 나타나는 불안의 평가와 치료)

  • Na, Chul
    • Korean Journal of Psychosomatic Medicine
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    • v.3 no.2
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    • pp.214-221
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    • 1995
  • There appears to be an increased incidence of anxiety symptoms in association with certain medical illness. It is usually assumed that certain medical disorders are directly associated with anxiety symptoms in that the pathophysilolgy of the medical illness somehow causes the anxiety symptoms. However, the pathophysilolgies of many such medical illnesses as well as anxiety are not known and no discrete group of medical illnesses is clearly more likely to produce anxiety symptoms than any other Moreover, anxiety symptoms may be the representation of other psychiatric symptoms, like depression and delirium. Though it is important to differentiate primary and other causes(secondary) of anxiety clinically, the clear differentiation is somewhat arbitrary, as the confusion of mind-body dichotomy. for the purpose of accurate treatment of anxiety symptoms relating medical illness, this review article focuses on those clinical features and mechanisms of anxiety that are potentially useful in differential diagnosis.

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Fine Needle Aspiration Cytologic Findings of Pulmonary Neuroendocrine Tumors (폐의 신경내분비 종양의 세침흡인 세포검사 소견)

  • Koh, Jae-Soo
    • The Korean Journal of Cytopathology
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    • v.19 no.1
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    • pp.9-15
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    • 2008
  • The major categories of neuroendocrine tumors of lung are typical carcinoid, atypical carcinoid, large cell neuroendocrine carcinoma, and small cell carcinoma. The histologic classification criteria of neuroendocrine tumors are well documented in the "WHO Classification of Tumors" based on mitotic figures and necrosis. Cytologic characteristics of neuroendocrine tumors are trabecular, acinar, and solid arrangement of tumor cells and occasional rosette formation. Nuclear chromatin patterns are characteristically described as "salt and pepper chromatin pattern". Many of cytologic classifications documented in the literature are before the "WHO Classification". In this review, the cytologic features of pulmonary neuroendocrine tumors are documented according to the WHO classification, and recent concepts of neuroendocrine tumors of lung are discussed.

The Design, Construction and Flight of Human Powered Aircraft Sky Runner (인력비행기 스카이 러너 설계.제작.비행)

  • Lee, Ki-Young;Choy, Seoung-Ok;Oh, Jang-Geun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.4
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    • pp.534-541
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    • 2010
  • With the financial sponsorship of FKI and six other companies, the design and construction of the human powered aircraft Sky Runner has been begun to design in December of 2008. And it flew in late December of 2009. The original design configuration was continuously modified in response to test results as a 30.36m span, $35.25m^2$ wing area, 26.0 aspect ratio and 39.8kg of empty weight. Although, we have made only 150m flight flying a few seconds so far however, it will contribute to the research of ultra-light and long duration flying planes. A brief review of some design features, wing layout, prop design, fabrication and flight test results are presented.

Firm Heterogeneity and Location Choice: The Case of South Korean Manufacturing Multinationals

  • Han, Jae-Joon;Lee, Hongshik;Lee, Insu
    • East Asian Economic Review
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    • v.16 no.4
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    • pp.315-331
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    • 2012
  • Previous studies of location choice have focused on country-level data more than firm-level data and been more concerned with host countries' distinctive features than with firm heterogeneity. Therefore, they do not answer the question of who will go where in terms of location choice. To analyze the role of firm heterogeneity in determining location choice, we develop a theoretical model and analyze data on 3,644 Korean manufacturing multinationals operating in 87 countries between 1982 and 2006. The results of our conditional logit analysis indicate that not only host country characteristics but also firm heterogeneous factors such as productivity, labor intensity, and size have considerable influence on the decision of where to locate FDI.

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Fractal Structure of the Stock Markets of Leading Asian Countries

  • Gunay, Samet
    • East Asian Economic Review
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    • v.18 no.4
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    • pp.367-394
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    • 2014
  • In this study, we examined the fractal structure of the Nikkei225, HangSeng, Shanghai Stock Exchange and Straits Times Index of Singapore. Empirical analysis was performed via non-parametric, semi-parametric long memory tests and also fractal dimension calculations. In order to avoid spurious long memory features, besides the Detrended Fluctuations Analysis (DFA), we also used Smith's (2005) modified GPH method. As for fractal dimension calculations, they were conducted via Box-Counting and Variation (p=1) tests. According to the results, while there is no long memory property in log returns of any index, we found evidence for long memory properties in the volatility of the HangSeng, the Shanghai Stock Exchange and the Straits Times Index. However, we could not find any sign of long memory in the volatility of Nikkei225 index using either the DFA or modified GPH test. Fractal dimension analysis also demonstrated that all raw index prices have fractal structure properties except for the Nikkei225 index. These findings showed that the Nikkei225 index has the most efficient market properties among these markets.

A Comparison Study of the Test for Right Censored and Grouped Data

  • Park, Hyo-Il
    • Communications for Statistical Applications and Methods
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    • v.22 no.4
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    • pp.313-320
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    • 2015
  • In this research, we compare the efficiency of two test procedures proposed by Prentice and Gloeckler (1978) and Park and Hong (2009) for grouped data with possible right censored observations. Both test statistics were derived using the likelihood ratio principle, but under different semi-parametric models. We review the two statistics with asymptotic normality and consider obtaining empirical powers through a simulation study. The simulation study considers two types of models the location translation model and the scale model. We discuss some interesting features related to the grouped data and obtain null distribution functions with a re-sampling method. Finally we indicate topics for future research.