• 제목/요약/키워드: Chain Structure

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Relationship between Chemical Structure and Antimicrobial Activities of Isothiocyanates from Cruciferous Vegetables against Oral Pathogens

  • Ko, Mi-Ok;Kim, Mi-Bo;Lim, Sang-Bin
    • Journal of Microbiology and Biotechnology
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    • 제26권12호
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    • pp.2036-2042
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    • 2016
  • We evaluated the potentials of 10 isothiocyanates (ITCs) from cruciferous vegetables and radish root hydrolysate for inhibiting the growth of oral pathogens, with an emphasis on assessing any structure-function relationship. Structural differences in ITCs impacted their antimicrobial activities against oral pathogens differently. The indolyl ITC (indol-3-carbinol) was the most potent inhibitor of the growth of oral pathogens, followed by aromatic ITCs (benzyl ITC (BITC) and phenylethyl ITC (PEITC)) and aliphatic ITCs (erucin, iberin, and sulforaphene). Sulforaphene, which is similar in structure, but has one double bond, showed higher antimicrobial activity than sulforaphane. Erucin, which has a thiol group, showed higher antimicrobial activity than sulforaphane, which has a sulfinyl group. BITC and iberin with a short chain exhibited higher antimicrobial potential than PEITC and sulforaphane with a longer chain, respectively. ITCs have strong antimicrobial activities and may be useful in the prevention and management of dental caries.

Structural Studies of Respirasome by Cryo-Electron Microscopy

  • Jeon, Tae Jin;Kim, Ho Min;Ryu, Seong Eon
    • Applied Microscopy
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    • 제48권4호
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    • pp.81-86
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    • 2018
  • The respiratory chain complex forms a supercomplex (SC) in the inner mitochondrial membrane. This complex facilitates the process of electron transfer to produce the proton gradient used to synthesize ATP. Understanding the precise structure of the SC is considered an important challenge. However, it has not yet been reported. The development of a Cryo-electron microscopy (EM) technique provides an effective way to obtain high-resolution micrographs to determine the high-resolution three-dimensional structure of biomolecules. In this brief review, the currently reported Cryo-EM structures of the mammalian respirasome have been described in order to establish a direction for further research in the respiratory system.

Digital Immigrants' Goal Structures in Online Learning

  • Lee, Jung Hoon;Nam, Jin Young;Jung, Yoon Hyuk
    • 한국정보시스템학회지:정보시스템연구
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    • 제30권2호
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    • pp.127-146
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    • 2021
  • Research Purpose Advances in digital technology have facilitated the widespread adoption of online learning, which has become a substantial way of learning. Although digital immigrants have become a main group of users of learning online, there is a lack of understanding of their online learning. This study aims to explore digital immigrants' adoption of online learning from the goal-pursuit perspective to gain insight into how they use online learning. Research Method A laddering interview was conducted with 22 Korean adults to elicit their goals in online learning. Then, a means-end chain analysis was used to derive their hierarchical goal structure. Findings The results reveal digital immigrants' goal structure of online learning, consisting of four attributes of online learning (e.g., accessibility, diversity, up-to-dateness, and repeatability) and six goals (e.g., self-esteem, enjoyment, recognition, productivity, gaining insights, and positive relations). This study contributes to the literature by providing a rich picture of their use of online learning.

가치사슬 활동이 종합병원 경영성과에 미치는 영향 분석 (The Effects of Value Chain Activity on General Hospital Management Performance)

  • 백승준;김영훈;김한성;최영진;한휘종;윤병준;우정식;김효정
    • 한국병원경영학회지
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    • 제19권3호
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    • pp.11-28
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    • 2014
  • This study, targeting Korean tertiary hospitals and general hospitals, aims to analyze how value chain model in health and medical institution suggested by Duncan and else influences on hospital management. A survey was conducted to verify the actual proof analysis of this study model. 880 questionnaires were distributed to entire 88 hospitals and 739 copies were returned from 76 hospitals. This study mainly consists of three steps to analyze the effect value chain activity has on management performance of general hospitals. For the first step, we analyzed the effects service delivery activity has on management performance. For the second step, we analyzed the effects service support activity has on management performance and for the third, we analyzed the effects interaction between service delivery activity and service support activity has on management performance. The main results of this study are as follows. First, in terms of the management performance of scale, the factors which influenced on daily charge of outpatient were service activity before treatment, at the moment of treatment and value chain activity, while more important factors in daily charge of inpatient were organizational culture, organizational structure and value chain activity. In terms of management performance of quality, the factors which influenced on the first medical examination rate of outpatient were service activity before, at the moment of and after treatment, while activity at the moment of treatment, organizational structure, and value chain activity which is interaction were more important factors in average length of stay. In terms of non-financial performance, the management performance factors which influenced on job satisfaction were service activity at the moment of, after the treatment and value chain activity, while organizational culture, strategy resources and value chain activity which is interaction were more important factors in job commitment. Secondly, all the service support activity, service delivery activity and value chain activity had statistically significant effect on management performance. Among the three factors, service support activity had relatively high effect than others.

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Hydrothermal Synthesis, Crystal Structure of Four Novel Complexes Based on Thiabendazole Ligand

  • Wei, Shui-Qiang;Lin, Cui-Wu;Yin, Xian-Hong;Huang, Yue-Jiao;Luo, Pei-Qi
    • Bulletin of the Korean Chemical Society
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    • 제33권9호
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    • pp.2917-2924
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    • 2012
  • Four novel metal-organic complexes $[Cd_2(IP)_2(TBZ)_2(H_2O)_2]{\cdot}(H_2O)$ (1), $[Zn_4(IP)_4(TBZ)_4]{\cdot}2(H_2O)$ (2), $[Zn_2(BTC)(TBZ)_2(CO_2H)]$ (3), [Co(PDC)(TBZ)] (4) (where IP = isophthalate; TBZ = thiabendazole; BTC = 1,3,5-benzenetricarboxylate; PDC = pyridine-3,4-dicarboxylate) have been prepared and characterized by IR spectrum, elemental analysis, thermogravimetric analysis, and single-crystal X-ray diffraction. X-ray structure analysis reveals that 1, 2, and 3 are one-dimensional chain polymers, while 4 is a two-dimensional network polymer. The TBZ acts as a typical chelating ligand coordinated to the metal center in all complexes. The 1D chain architecture of 1 is constructed from isophthalates and cadmium atoms. A simultaneous presence of chelating, monodentate and bidentate coordination modes of IP ligands is observed in complex 2. In complex 3, the 16-membered rings are alternately arranged forming an infinite 1D double-chain structure. The 2D skeleton of 4 is formed by cobalt ions as nodes and PDC dianions as spacers, through coordination bonds. The hydrogen bonds and ${\pi}-{\pi}$ stacking play important roles in affecting the final structure where complexes 1 and 3 have 2D supramolecular networks, while complexes 2 and 4 have 3D supramolecular architectures.

개도국 농업발전을 위한 농산물 가치사슬 개선 전략: 캄보디아 사례를 중심으로 (Improvement Strategies of Agro-Value Chain for Agricultural Development in Developing Countries: The Case of Cambodia)

  • 김동환
    • 유통과학연구
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    • 제14권4호
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    • pp.127-134
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    • 2016
  • Purpose - Value chain in agriculture refers to direct and indirect activities related to value-added process from raw materials to final products in agricultural industries. In recent years, value chain analysis has become more important in the area of agricultural development. This article reviews the concept and importance of value chain analysis in the context of agricultural development and attempts to suggest improvement strategies. Research design, data, methodology - A literature survey was conducted for value chain analysis for agricultural development. The case of agro-value chain in Cambodia was deeply analyzed based upon interviews with government officers and related experts. Results - It seems that agro-value chain in developing countries are not well developed and does not carry out appropriate functions, compared to developed countries. Because value adding facilities, such as storage, processing and packing plants, milling plants, and etc. are not sufficiently constructed, the quality of agricultural products is low. Especially developing countries may loose opportunities to increase value of their product by exporting their agricultural products as raw materials to neighboring countries. Value adding process is also mainly controlled by traders in local markets or wholesale markets in urban areas. Farmers therefore can get lower share of final value of agricultural products compared to the shares paid to traders. Lastly it is argued that governments of developing countries do not play an active role in developing value chains and do not carry out coordinating functions in an effective and efficient manner. Conclusions - The first step to improve agro-value chain in developing countries is to identify and analyze value chain structure of agricultural products and to make development strategies and implementation programs. For improving value chain of agricultural products in developing countries, it is required to provide not only plans for constructing hardwares, such as wholesale markets, storage facilities, processing and packing plants, and etc., but also plans for improving softwares, such as measures for improving product quality and safety, setting up grade and standard, providing market information, and nurturing producer cooperatives.

The analysis of value chains for the chestnut industry in Chungcheongnam-do

  • Lee, Bo-Hwi;Ji, Dong-Hyun;Kang, Kil-Nam;Kim, Se-Bin
    • 농업과학연구
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    • 제45권2호
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    • pp.298-307
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    • 2018
  • The aim of this study was to enhance the value of the chestnut industry by analyzing the value chain structure. Based on the value chain theory, it is divided into primary activities and support activities. Thus, in total, 27 subjects from Gongju, Buyeo, and Cheongyang were interviewed and self-administered questionnaire. Regarding the value chain structure of the chestnut industry, the primary activities consisted of production followed by cultivation and storing, sorting and packaging, transportation and marketing sales. The support activities were divided into production infrastructure, policy, R&D, and systematization. The primary activities are able to maximize profits through cost reductions. The production was divided into general and environmentally friendly cultivation. Depending on the labor force, it is family-centered labor. However, the installation of harvest nets depends on a hired labor force (40 - 60%) such that it would be necessary to have a mechanized harvest to replace the manpower for the cost reduction. Transportation, marketing sales, and backdoor selling (38.1%) were higher than the existing channels (31.0%) using the National Agricultural Cooperative Federation. The enhancement of value could be created by maximizing profits through the reinforcement of the links between each subject. The production showed strong connections with cultivation/storing, sorting/packing, and backdoor selling and the National Forestry Cooperative Federation. The processing stage is a very simple structure, it would be necessary to have R&D and to support promotions, infrastructure, machines, and sales increases, which should be expanded by connections with other industries like the food industry.

Mobile-DTV 응용을 위한 광대역 DCO 설계 (Design of a Wide Tuning Range DCO for Mobile-DTV Applications)

  • 송성근;박성모
    • 한국멀티미디어학회논문지
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    • 제14권5호
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    • pp.614-621
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    • 2011
  • 본 논문은 Mobile-DTV 응용을 위한 광대역 DCO(Digitally Controlled Oscillator)의 설계에 대해 다룬다. DCO는 발전 주파수를 생성하는 회로로 ADPLL(All-digital Phase-locked Loop)의 핵심 블록이다. 본 논문에서는 광대역 DCO 설계를 위해 기존의 Fixed delay chain을 변형한 binary delay chain(BDC) 구조를 제안하였다. 제안된 구조는 $2^i$ 형태로 $0{\leq}i{\leq}n-1$ 범위의 서로 다른 지연시간을 갖는 여러개의 지연셀의 조합을 통해 발진 주파수를 생성한다. BDC 형태는 응용에 맞는 지연셀의 조합과 해상도를 선택할 수 있기 때문에 지연셀의 최적화가 가능하다. 제안된 DCO는 1.8V chartered $0.18{\mu}m$ CMOS 공정을 이용하여 Cadence사의 Spectre RF 툴에서 검증되었다. 실험결과 77MHz~2.07GHz의 주파수 대역파 3ps의 해상도를 나타내었다. 위상잡음은 Mobile-DTV 표준의 최대 주파수인 1675MHz에서 -101dBc/Hz@1MHz를 나타내었고 전력소모는 5.87mW를 나타내었다. 이는 ATSC-M/H, DVB-H, ISDB-T, T-DMB 등 Mobile-DTV의 표준을 만족한다.

Force-field가 고분자 분리막의 기체 투과거동에 미치는 영향 (Effect of Types of Force-fields on Gas Transport Thorough Polymer Membrane)

  • 이지수;박치훈
    • 멤브레인
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    • 제29권1호
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    • pp.37-43
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    • 2019
  • 본 연구에서는 분자동역학에서 원자의 움직임을 정의하는 가장 중요한 요소인 force-field가 실제 고분자 및 기체 분자의 움직임에 어떠한 영향을 주는지 알아보고자 하였다. Repeat unit과 고분자 구조는 본 연구에서 사용된 5종의 force-field 에서 모두 정상적으로 작용을 하였고, 최종 고분자 3D 모델에서 고분자 linear chain의 분포에서도 큰 차이를 보이지 않았다. 그러나 실제 기체 분자의 움직임은 매우 다른 경향을 나타내었으며, 이는 같은 functional form을 사용하는 COMPASS와 pcff 에서도 관찰되었다. 따라서 동일한 구조라고 하더라도 기체 분자의 운동은 시간에 따라 지속적으로 force-field의 영향 하에서 움직이기 때문에, 고분자 linear chain과 같은 거대 분자에 비하여 그 영향을 훨씬 크게 받는다는 것을 알 수 있으며, 결론적으로 서로 다른 force-field의 사용 시에는 결과 비교에 있어서도 매우 신중을 기해야 할 것이다.

병원 선택 속성간의 계층적 구조 분석 (An Hierarchical Structure Analysis of Hospital Selection Attributes)

  • 차재빈;이훈영
    • 보건행정학회지
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    • 제21권2호
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    • pp.263-278
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    • 2011
  • As the competition among hospitals become intensified, hospital management is required to carry out more effective marketing and positioning of the hospital. Successful positioning of a hospital requires the knowledge about how the concrete attributes inherent in the medical service associated with the customer values that customers seek eventually in the medical service. Thus, it is required for hospital management to understand which hospital attributes should be emphasized in order to improve the customer values. The hierarchical structure of service attributes can provide valuable information about effective positioning and advertising. To obtain such knowledge, we employed the order analysis technique as an objective means-end chain method. Order analysis is useful for identifying the causal structure among attributes. Thus, we can examine the underlying causal relationship and eventually the vertical structure of hospital selection attributes. For this study, we conducted a survey to obtain 370 responses for the analysis. The result suggests that hospital management had better increase the scale of hospital, improve the services of health care providers, and modernize the hospital facilities and equipments so as to enhance customer values and eventually to lead them to recommend the hospital to others. Our findings would provide the valuable information for hospital management to develop the more effective hospital positioning and marketing strategies.