• Title/Summary/Keyword: Transport Mechanism

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Analysis of AM and AEM Oxides Behavior in a SF Electrolytic Reduction Process (사용후핵연료 전기환원 공정에서의 알카리, 알카리토 금속 산화물들의 거동 분석)

  • 박병흥;강대승;서중석;박성원
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2004.06a
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    • pp.268-277
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    • 2004
  • process (ACP), electrochemical properties of high heat-generating alkali and alkali earth oxides in molten salt were measured and the behavior of those elements were analyzed. The reduction potentials of Cs, Sr, and Ba in a molten LiCl-$Li_2O$ system were more cathodic than that of Li and closely located one another. Thus, it is expected that the alkali and alkali earth would not hinder the reaction mechanism which is via lithium reduction. Alkali and alkali earth metals are likely to recycle into molten salt when the process is operated beyond metal reduction potentials and the effect of electric current on the mass transport is also determined by measuring the metal concentrations in the molten salt phase at different current conditions.

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The Pharmacology of Botulinum Toxin (보툴리눔 독소의 약리)

  • Lee, Sang Hyuk;Lee, Hyun Sub;Jin, Sung Min
    • Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
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    • v.23 no.2
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    • pp.93-98
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    • 2012
  • Botulinum toxins are the most potent toxins known to mankind. Botulinum toxin acts by blocking the cholinergic neuromuscular or the cholinergic autonomic innervation of exocrine glands and smooth muscles. Seven distinct antigenic botulinum toxins (A, B, C, D, E, F and G) produced by different strains of Clostridium botulinum have been described and only A and B type of botulinum toxins were clinically used. Toxins were consisted of a heavy chain with a molecular weight of 100 kD and a light chain with a molecular weight of 50 kD. Toxins are bound with an astounding selectivity to glycoprotein structures located on the cholinergic nerve terminal. Subsequently light chain of toxin is internalized and cleaves different proteins of the acetylcholine transport protein cascade transporting the acetylcholine vesicle from the intracellular space into the synaptic cleft. After a decade of therapeutic application of the toxin, no anaphylaxis or deaths have been reported and systemic adverse effects have not been reported so far. However the toxin's immunologic properties can lead to the stimulation of antibody production, potentially rendering further treatments ineffective. Botulinum toxin is a safe and effective treatment. Use of botulinum toxin in clinical medicine has grown exponentially in recent years, and many parts of the human body are now being targeted for therapeutic purposes.

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Transcriptomic Features of Echinococcus granulosus Protoscolex during the Encystation Process

  • Fan, Junjie;Wu, Hongye;Li, Kai;Liu, Xunuo;Tan, Qingqing;Cao, Wenqiao;Liang, Bo;Ye, Bin
    • Parasites, Hosts and Diseases
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    • v.58 no.3
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    • pp.287-299
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    • 2020
  • Cystic echinococcosis (CE) is a zoonotic infection caused by Echinococcus granulosus larvae. It seriously affects the development of animal husbandry and endangers human health. Due to a poor understanding of the cystic fluid formation pathway, there is currently a lack of innovative methods for the prevention and treatment of CE. In this study, the protoscoleces (PSCs) in the encystation process were analyzed by high-throughput RNA sequencing. A total of 32,401 transcripts and 14,903 cDNAs revealed numbers of new genes and transcripts, stage-specific genes, and differently expressed genes. Genes encoding proteins involved in signaling pathways, such as putative G-protein coupled receptor, tyrosine kinases, and serine/threonine protein kinase, were predominantly up-regulated during the encystation process. Antioxidant enzymes included cytochrome c oxidase, thioredoxin glutathione, and glutathione peroxidase were a high expression level. Intriguingly, KEGG enrichment suggested that differentially up-regulated genes involved in the vasopressin-regulated water reabsorption metabolic pathway may play important roles in the transport of proteins, carbohydrates, and other substances. These results provide valuable information on the mechanism of cystic fluid production during the encystation process, and provide a basis for further studies on the molecular mechanisms of growth and development of PSCs.

Study on Hindered Diffusion of Single Polyelectrolyte Chain in Micro-Pores by Employing Brownian Dynamics Simulations (브라운 동력학 시뮬레이션에 의한 미세기공에서 단일한 다가전해질 사슬의 제한확산 연구)

  • 전명석;곽현욱
    • Membrane Journal
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    • v.12 no.4
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    • pp.207-215
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    • 2002
  • The hindered diffusion in confined spaces is an important phenomenon to understand in a micro-scale the filtration mechanism determined by the particle motion in membrane pores. Compared to the case of spherical colloids, both the theoretical investigations and the experiments on the hindered diffusion of polyelectrolytes is actually more difficult, due to lots of relevant parameters resulting from the complicated conformational properties of the polyelectrolyte chain. We have successfully performed the Brownian dynamics simulations upon a single polyeiectrolyte confined in a slit-like pore, where a coarse-grained bead-spring model incorporated with Debye-Huckel interaction is properly adopted. For the given sizes of both the polyelectrolyte and the pore width, the hindered diffusion coefficient decreases as the solution ionic concentration decreases. It is evident that a charge effect of the pore wall enhances the hindered diffusion of polyelectrolyte. Simulation results allow us to make sense of the diffusive transport through the micro-pore, which is restricted by the influences of the steric hindrance of polyelectrolytes as well as the electrostatic repulsion between the polyelectrolytes and pore wall.

Research on the Influence of Transformational Leadership on the Employee's Job Satisfaction and Job Performance (변혁적 리더십과 직원들의 직무만족도 및 직무성과와의 관계에 관한 연구)

  • Li, Nan;Chung, Gi-Young;Kim, Hyung-Ho
    • Journal of the Korea Convergence Society
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    • v.11 no.6
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    • pp.269-279
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    • 2020
  • The leader has an indispensable role in the enterprise. This article takes transformational leadership as the research object and introduces job satisfaction and job performance as variables. It is aimed to explore the impact of various dimensions of transformational leadership on employee performance and satisfaction, and to try to find the acting mechanism of the effect of transformational leadership on employee performance. The study used a questionnaire survey method and SPSS23.0 for statistical analysis. Through the analysis of 378 questionnaire surveys, it was found that the four constituent variables of transformational leadership would have different degrees of influence on job performance and satisfaction. Enterprise leaders should put emphasis on the choice of leadership style and pay special attention to the work attitude of employees. This study provides useful enlightenment for companies to carry out human resource management work. However, this study did not verify whether job satisfaction has an intermediary role in between transformational leadership and job performance, which is also an area that needs to be further studied in the future.

Analysis on Changes in Strength, Chloride Diffusion, and Passed Charges in Normal Concrete Considering Ages and Mix Proportions (재령 및 배합특성을 고려한 보통 콘크리트의 강도, 염화물 확산계수, 통과전하량 변화 분석)

  • Lee, Hack-Soo;Kwon, Seung-Jun
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.5 no.1
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    • pp.1-7
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    • 2017
  • Concrete behavior in early-age is changing due to hydration reaction with time, and a resistance to chloride attack and strength development are different characterized. In the present work, changing strength and resistance to chloride attack are evaluated with ages from 28 days to 6 months. For the purpose, strength, diffusion coefficient, and passed charge are evaluated for normal concrete with 3 different mix proportions considering 28-day and 6-month curing conditions. With increasing concrete age, the changing ratio of strength falls on the level of 135.3~138.3%, while diffusion coefficient and passed charge shows 41.8%~51.1% and 53.6%~70.0%, respectively. The results of chloride diffusion coefficient and passed charge show relatively similar changing ratios since they are much dependent on the chloride migration velocity in electrical field. The changing ratios in chloride behaviors are evaluated to be much larger than those in compressive strength since the ion transport mechanism is proportional to not porosity but square of porosity.

Definition of Network Resource and Network Service Interface for Grid Network Resource Manager (그리드 네트워크 자원 관리기를 위한 네트워크 자원과 네트워크 서비스 인터페이스의 정의)

  • Kim, Hae-Hyun;Cha, Young-Wook;Han, Jang-Soo;Kim, Choon-Hee;Kong, Jong-Uk;Seok, Woo-Jin
    • The KIPS Transactions:PartC
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    • v.16C no.4
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    • pp.511-520
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    • 2009
  • Grid technology enables high performance computation and mass data processing by connecting geographically distributed computing resources to high-speed network. To carry on grid tasks requiring guaranteed quality of service, we need to build converged infrastructure which controls and manages network resources as well as computing resources. In this paper, we defined grid network service interface and information model to support grid network path, resource creation and reservation. In addition to resource creation and reservation messages of the existing GLIF, grid network path and notification messages were defined in the grid network service interface. We also defined related statuses and messages for two-phase resource reservation mechanism. We designed and implemented network resource management system based on the grid network information model and service interface. We experimented in resource reservation, allocation and release of network resources in grid environment with GMPLS control and transport network.

Beach Deformation Mechanisms in Haeundae Beach (해운대(海雲臺) 해수욕장(海水浴場)의 해빈변형기구(海濱變形機構))

  • Lee, Jong Sup;Park, II Heum;Kim, Cha Kyum
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.3
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    • pp.595-605
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    • 1994
  • The field observations. data analyses and numerical experiments are performed to investigate the short and long term beach deformation mechanisms in Haeundae beach. The schematic diagrams of deposition and erosion mechanism due to the attack of typhoons are described from the analysis on the beach widths and profiles. The short term beach deformation depends strongly on the characteristics of incident waves and wave-induced currents. The main incident wave and the calibration parameters of the shoreline change model are determined using the beach width data. Beacause the main incident wave approaches obliquly from the SE direction, the net westward longshore sediment transport occurs. Therefore the unbalance of longshore sediment budget in the east of the beach where the sediment source dose not exist causes a beach erosion. On the other hand, the deposited sand in the west is lost offshore by the storm wave action.

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Development of the Manual Opening and Closing Algorithm for Vertical Rope Type Platform Safe Door and Its Evaluation (상하개폐형 RPSD의 수동개폐 알고리즘 개발 및 평가)

  • Choi, Gapyeol;Kim, Hyun
    • Journal of Korean Society of Transportation
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    • v.32 no.3
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    • pp.248-255
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    • 2014
  • Though the Platform Screen Door System (PSD) has received a positive evaluation and is installed in all the Urban Railroad platforms, PSD is not installed in the Intercity Railroad platforms. The limitation of PSD in the Intercity Railroad platforms is due to the fact that first, various types of trains such as KTX, Saemaeul, Mugunghwa, and Nuriro stop at the platforms and their locations of the doors are different and secondly, they are not operated under ATO (automatic train operation). RPSD system currently under research and development, on the other hand, is based on the improved door that slides up and down and can be installed in any Intercity Railroad platform regardless of the length of the train, the location of doors, and the number of doors. This study considers the mechanism of RPSD, develops a manual open/close algorithm, and evaluates the function of RPSD. The results show that the manual open/close algorithm achieves a significant improvement in efficiency when provided with power supply.

Influence of Charge Transport of Pt-CdSe-Pt Nanodumbbells and Pt Nanoparticles/GaN on Catalytic Activity of CO Oxidation

  • Kim, Sun Mi;Lee, Seon Joo;Kim, Seunghyun;Kwon, Sangku;Yee, Kiju;Song, Hyunjoon;Somorjai, Gabor A.;Park, Jeong Young
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.164-164
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    • 2013
  • Among multicomponent nanostructures, hybrid nanocatalysts consisting of metal nanoparticle-semiconductor junctions offer an interesting platform to study the role of metal-oxide interfaces and hot electron flows in heterogeneous catalysis. In this study, we report that hot carriers generated upon photon absorption significantly impact the catalytic activity of CO oxidation. We found that Pt-CdSe-Pt nanodumbbells exhibited a higher turnover frequency by a factor of two during irradiation by light with energy higher than the bandgap of CdSe, while the turnover rate on bare Pt nanoparticles didn't depend on light irradiation. We also found that Pt nanoparticles deposited on a GaN substrate under light irradiation exhibit changes in catalytic activity of CO oxidation that depends on the type of doping of the GaN. We suppose that hot electrons are generated upon the absorption of photons by the semiconducting nanorods or substrates, whereafter the hot electrons are injected into the Pt nanoparticles, resulting in the change in catalytic activity. We discuss the possible mechanism for how hot carrier flows generated during light irradiation affect the catalytic activity of CO oxidation.

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