• Title/Summary/Keyword: Selective Assembly

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Preparation and Pore-Characteristics Control of Nano-Porous Materials using Organometallic Building Blocks

  • Oh, Gyu-Hwan;Park, Chong-Rae
    • Carbon letters
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    • v.4 no.1
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    • pp.1-9
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    • 2003
  • Recently, the control of pore-characteristics of nano-porous materials has been studied extensively because of their unique applications, which includes size-selective separation, gas adsorption/storage, heterogeneous catalysis, etc. The most widely adopted techniques for controlling pore characteristics include the utilization of pillar effect by metal oxide and of templates such as zeolites. More recently, coordination polymers constructed by transition metal ions and bridging organic ligands have afforded new types of nano-porous materials, porous metal-organic framework(porous MOF), with high degree and uniformity of porosity. The pore characteristics of these porous MOFs can be designed by controlling the coordination number and geometry of selected metal, e.g transition metal and rare-earth metal, and the size, rigidity, and coordination site of ligand. The synthesis of porous MOF by the assembly of metal ions with di-, tri-, and poly-topic N-bound organic linkers such as 4,4'-bipyridine(BPY) or multidentate linkers such as carboxylates, which allow for the formation of more rigid frameworks due to their ability to aggregate metal ions into M-O-C cluster, have been reported. Other porous MOF from co-ligand system or the ligand with both C-O and C-N type linkage can afford to control the shape and size of pores. Furthermore, for the rigidity and thermal stability of porous MOF, ring-type ligand such as porphyrin derivatives and ligands with ability of secondary bonding such as hydrogen and ionic bonding have been studied.

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Organic Memory Device Using Self-Assembled Monolayer of Nanoparticles (나노입자 자기조립 단일층을 이용한 유기메모리 소자)

  • Jung, Hunsang;Oh, Sewook;Kim, Yejin;Kim, Minkeun;Lee, Hyun Ho
    • Applied Chemistry for Engineering
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    • v.23 no.6
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    • pp.515-520
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    • 2012
  • In this review, the fabrication of silicon based memory capacitor and organic memory thin film transistors (TFTs) was discussed for their potential identification tag applications and biosensor applications. Metal or non-metal nanoparticles (NPs) could be capped with chemicals or biomolecules such as protein and oligo-DNA, and also be self-assembly monolayered on corresponding target biomolecules conjugated dielectric layers. The monolayered NPs were formed to be charging elements of a nano floating gate layer as forming organic memody deivces. In particular, the strong and selective binding events of the NPs through biomolecular interactions exhibited effective electrostatic phenomena in memory capacitors and TFTs formats. In addition, memory devices fabricated as organic thin film transistors (OTFTs) have been intensively introduced to facilitate organic electronics era on flexible substrates. The memory OTFTs could be applicable eventually to the development of new conceptual devices.

Whole-Genome Resequencing Analysis of Hanwoo and Yanbian Cattle to Identify Genome-Wide SNPs and Signatures of Selection

  • Choi, Jung-Woo;Choi, Bong-Hwan;Lee, Seung-Hwan;Lee, Seung-Soo;Kim, Hyeong-Cheol;Yu, Dayeong;Chung, Won-Hyong;Lee, Kyung-Tai;Chai, Han-Ha;Cho, Yong-Min;Lim, Dajeong
    • Molecules and Cells
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    • v.38 no.5
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    • pp.466-473
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    • 2015
  • Over the last 30 years, Hanwoo has been selectively bred to improve economically important traits. Hanwoo is currently the representative Korean native beef cattle breed, and it is believed that it shared an ancestor with a Chinese breed, Yanbian cattle, until the last century. However, these two breeds have experienced different selection pressures during recent decades. Here, we whole-genome sequenced 10 animals each of Hanwoo and Yanbian cattle (20 total) using the Illumina HiSeq 2000 sequencer. A total of approximately 3.12 and 3.07 billion sequence reads were mapped to the bovine reference sequence assembly (UMD 3.1) at an average of approximately 10.71- and 10.53-fold coverage for Hanwoo and Yanbian cattle, respectively. A total of 17,936,399 single nucleotide polymorphisms (SNPs) were yielded, of which 22.3% were found to be novel. By annotating the SNPs, we further retrieved numerous nonsynonymous SNPs that may be associated with traits of interest in cattle. Furthermore, we performed whole-genome screening to detect signatures of selection throughout the genome. We located several promising selective sweeps that are potentially responsible for economically important traits in cattle; the PPP1R12A gene is an example of a gene that potentially affects intramuscular fat content. These discoveries provide valuable genomic information regarding potential genomic markers that could predict traits of interest for breeding programs of these cattle breeds.

A Study of Smart Convergence Strategies for Enhancing a Creative Economy: Lessons from Korea (창조경제 활성화를 위한 스마트융합 전략방안)

  • Kim, Yong-Beom;Kwak, Jeongho
    • Journal of Internet Computing and Services
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    • v.15 no.4
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    • pp.67-79
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    • 2014
  • One of the core policies recently implemented by the Korean government is the introduction of a creative economy, a concept that integrates ICT with the existing economic structure in order to create new growth factors and jobs. In June of 2013, the National Assembly passed a bill for the institutional practice of a creative economy. The concept of a creative economy is to integrate industries centered on ICT in order to form a new-concept industry paradigm that creates new values and services that exceed past industrial categories. In other words, smart convergence, which integrates ICT with various industries, is evaluated as a core factor for boosting the creative economy. Thus, based on the definition of 'smart convergence', this study predicted the economic effects and sociocultural changes that will ensue due to the future era of smart convergence. Also, this study proposes policies for enhancing the creative economy in various ways. More specifically, in-depth interviews with convergence industry experts were carried out and quantitative analyses were performed employing a Solow Model. Furthermore, as a means to revitalize the creative economy, this study underscores the significance of the preemptive institutionalization of legislations and suggests several policy proposals regarding smart convergence rooted in market supply and the demand chain, smart convergence through selective focus, and smart work. This study is differentiated from previous studies that have only focused in establishing theories in that it offers quantitative research with a consideration of the feasibility of proposed policies. The leading experience of Korea regarding smart convergence can provide important lessons to other countries that hope to promote a creative economy as a means to create new growth factors and jobs.

Research Trend on Depression of Korean Medical Students Based on Quantitative Studies (의과대학생 우울에 관한 국내 연구동향 : 양적연구를 중심으로)

  • Jeong, Joy;Lee, Soo Jin
    • The Journal of the Korea Contents Association
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    • v.21 no.9
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    • pp.446-457
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    • 2021
  • The aim of this study was to grasp the seriousness of depression problems in medical students by examining the research trends among them and to present desirable direction of the future study. A selective search has been conducted for literature published in Nurimedia (DBPIA), Korean studies Information Service System (KISS), Research Information Sharing Service (RISS), National Assembly Library (NANET) and National Digital Science Library (NDSL) databases. 18 papers have been selected for the final analysis. The results showed that studies on depression problems were published in very small proportion which researchers with diverse majors including psychiatry participated. Second, most of depression assessment tools usually measured depression only while some did various psychological symptoms. Third, independent t test was the most frequent analytic method. Last but not least, there was no research dealing with intervention about depression in medical students. To sum up, though numerous researchers with diverse specialties participated in the depression study and analyzed the data using various analyses and variables, there is a lack of intervention for depression of the medical students. Therefore, it is necessary to emphasize the necessity of practical intervention based on the evidence-based practice.

Executive Dysfunction and It's Relation to K-WAIS Scores in Mild Traumatic Brain Injury Patients with Normal Intelligence Quotient (정상 지능의 경도 외상성 뇌손상 환자에서 실행기능 장애 및 K-WAIS 점수들과의 관련성)

  • Lee, Dae-Bo;Yoon, In-Seon;Kim, Seon-Kyung;Rho, Seung-Ho;Park, Min-Cheol;Lee, Sang-Yeol
    • Korean Journal of Psychosomatic Medicine
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    • v.20 no.1
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    • pp.50-58
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    • 2012
  • Objectives : This study examined the selective deficits of executive function in patients with mild traumatic brain injury that in normal range of general intelligence level and aimed to analysis of the correlation between K-WAIS result and executive function. Methods : 59 subjects were included in this study, who were diagnosed as mild traumatic brain injury(MTBI) and they have visited in neuropsychiatric department of Wonkwang University Hospital during from March, 2005 to September, 2010. For measurement of general intelligence quotient, the Korean-Wechsler Adults Intelligence Scale(K-WAIS) was administered and for measurement of executive intelligence quotient(EIQ), Executive Intelligence Test(EXIT) was administered. Results : Of patients, 50.8% included at abnormal EIQ group. The patients of abnormal EIQ showed poorer full scale IQ(FIQ), performance IQ(PIQ) and in subscale that picture arrangement, digit symbol, digit span, block design, object assembly and comprehension were significantly different. In terms of relationships between K-WAIS and EIQ, FIQ and PIQ have positive correlation with EIQ. And in subscale, picture arrangement, digit symbol, digit span, block design, object assembly and comprehension show positive correlation with EIQ. Conclusion : This study suggest that MTBI patients with have normal range of general intelligence level may have deficit of executive function is common. The decline of FIQ, PIQ and some subscales of K-WAIS may suggest executive dysfunction in MTBI patients.

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