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Sample records for htr core design

  1. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Francesco Venneri; Chang-Keun Jo; Jae-Man Noh; Yonghee Kim; Claudio Filippone; Jonghwa Chang; Chris Hamilton; Young-Min Kim; Ji-Su Jun; Moon-Sung Cho; Hong-Sik Lim; MIchael A. Pope; Abderrafi M. Ougouag; Vincent Descotes; Brian Boer

    2010-09-01

    The Deep Burn (DB) Project is a U.S. Department of Energy sponsored feasibility study of Transuranic Management using high burnup fuel in the high temperature helium cooled reactor (HTR). The DB Project consists of seven tasks: project management, core and fuel analysis, spent fuel management, fuel cycle integration, TRU fuel modeling, TRU fuel qualification, and HTR fuel recycle. In the Phase II of the Project, we conducted nuclear analysis of TRU destruction/utilization in the HTR prismatic block design (Task 2.1), deep burn fuel/TRISO microanalysis (Task 2.3), and synergy with fast reactors (Task 4.2). The Task 2.1 covers the core physics design, thermo-hydraulic CFD analysis, and the thermofluid and safety analysis (low pressure conduction cooling, LPCC) of the HTR prismatic block design. The Task 2.3 covers the analysis of the structural behavior of TRISO fuel containing TRU at very high burnup level, i.e. exceeding 50% of FIMA. The Task 4.2 includes the self-cleaning HTR based on recycle of HTR-generated TRU in the same HTR. Chapter IV contains the design and analysis results of the 600MWth DB-HTR core physics with the cycle length, the average discharged burnup, heavy metal and plutonium consumptions, radial and axial power distributions, temperature reactivity coefficients. Also, it contains the analysis results of the 450MWth DB-HTR core physics and the analysis of the decay heat of a TRU loaded DB-HTR core. The evaluation of the hot spot fuel temperature of the fuel block in the DB-HTR (Deep-Burn High Temperature Reactor) core under full operating power conditions are described in Chapter V. The investigated designs are the 600MWth and 460MWth DB-HTRs. In Chapter VI, the thermo-fluid and safety of the 600MWth DB-HTRs has been analyzed to investigate a thermal-fluid design performance at the steady state and a passive safety performance during an LPCC event. Chapter VII describes the analysis results of the TRISO fuel microanalysis of the 600MWth and 450

  2. High Temperature Reactor (HTR) Deep Burn Core and Fuel Analysis: Design Selection for the Prismatic Block Reactor With Results from FY-2011 Activities

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    Michael A. Pope

    2011-10-01

    The Deep Burn (DB) Project is a U.S. Department of Energy sponsored feasibility study of Transuranic Management using high burnup fuel in the high temperature helium cooled reactor (HTR). The DB Project consists of seven tasks: project management, core and fuel analysis, spent fuel management, fuel cycle integration, TRU fuel modeling, TRU fuel qualification, and HTR fuel recycle. In the Phase II of the Project, we conducted nuclear analysis of TRU destruction/utilization in the HTR prismatic block design (Task 2.1), deep burn fuel/TRISO microanalysis (Task 2.3), and synergy with fast reactors (Task 4.2). The Task 2.1 covers the core physics design, thermo-hydraulic CFD analysis, and the thermofluid and safety analysis (low pressure conduction cooling, LPCC) of the HTR prismatic block design. The Task 2.3 covers the analysis of the structural behavior of TRISO fuel containing TRU at very high burnup level, i.e. exceeding 50% of FIMA. The Task 4.2 includes the self-cleaning HTR based on recycle of HTR-generated TRU in the same HTR. Chapter IV contains the design and analysis results of the 600MWth DB-HTR core physics with the cycle length, the average discharged burnup, heavy metal and plutonium consumptions, radial and axial power distributions, temperature reactivity coefficients. Also, it contains the analysis results of the 450MWth DB-HTR core physics and the analysis of the decay heat of a TRU loaded DB-HTR core. The evaluation of the hot spot fuel temperature of the fuel block in the DB-HTR (Deep-Burn High Temperature Reactor) core under full operating power conditions are described in Chapter V. The investigated designs are the 600MWth and 460MWth DB-HTRs. In Chapter VI, the thermo-fluid and safety of the 600MWth DB-HTRs has been analyzed to investigate a thermal-fluid design performance at the steady state and a passive safety performance during an LPCC event. Chapter VII describes the analysis results of the TRISO fuel microanalysis of the 600MWth and 450

  3. Monte Carlo Benchmark Calculations for HTR-10 Initial Core

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    Kim, Hong Chul; Kim, Soon Young; Shin, Chang Ho; Kim, Jong Kyung [Hanyang Univ., Seoul (Korea, Republic of); Noh, Jae Man [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2005-07-01

    These days, pebble-bed and other high-temperature gas-cooled reactor (HTGR) designs are once again in vogue in connection with hydrogen production. In this study, as a part of establishing Monte Carlo computation system for HTGR core analysis, some benchmark calculations for pebble-type HTGR were carried out using MCNP code. As a benchmark model, the initial core of the 10MW High Temperature Gas-cooled Reactor-Test Module (HTR-10) in China was selected. After the detailed MCNP modeling of the whole facility, benchmark calculations were performed. This study deals with the core physics benchmark problems proposed for HTR-10 reactor initial core. Results to benchmark problems have been obtained by MCNP5 Code.

  4. Design aspects of the Chinese modular high-temperature gas-cooled reactor HTR-PM

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    Zhang Zuoyi [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wu Zongxin [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Sun Yuliang [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Li Fu [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China)]. E-mail: lifu@tsinghua.edu.cn

    2006-03-15

    The modular high-temperature gas-cooled reactor (MHTGR) has distinct advantages in terms of inherent safety, economics potential, high efficiency, potential usage for hydrogen production, etc. The Chinese design of the MHTGR, named as high-temperature gas-cooled reactor-pebble bed module (HTR-PM), based on the technology and experience of the HTR-10, is currently in the conceptual phase. The HTR-PM demonstration plant is planned to be finished by 2012. The main philosophy of the HTR-PM project can be pinned down as: (1) safety, (2) standardization, (3) economy, and (4) proven technology. The work in the categories of marketing, organization, project and technology is done in predefined order. The biggest challenge for the HTR-PM is to ensure its economical viability while maintaining its inherent safety. A design of a 450 MWth annular pebble bed core connected with steam turbine is aimed for and presented in this paper.

  5. Monte Carlo criticality calculation for Pebble-type HTR-PROTEUS core

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    Kim, Hong Chul; Shin, Chang Ho; Han, Chi Young; Kim, Jong Kyung; Kim, Soon Young [Hanyang Univ., Seoul (Korea, Republic of); Noh, Jae Man [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    2004-07-01

    These days, pebble-bed and other High-Temperature Gas-cooled Reactor (HTGR) designs are once again in vogue in connection with hydrogen production. In this study, as a part of establishing Monte Carlo computation system for HTGR core analysis, some criticality calculations for pebble-type HTGR were carried out using MCNP code. Firstly, the pebble-bed cores of HTR-PROTEUS critical facility in Swiss were selected for the benchmark model, and, after the detailed MCNP modeling of the whole facility, criticality calculations were performed. It was also investigated the homogenization effect of TRISO fuel on criticality.

  6. Structural design of ceramic internals of HTR-10

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    Zhang Zhensheng E-mail: zhenshng@inet.tsinghua.edu.cn; Liu Junjie; He Shuyan; Zhang Zhengming; Yu Suyuan

    2002-10-01

    This article describes the structural design requirements, structural arrangement and structural features of the ceramic and metallic internals of the 10 MW high-temperature gas-cooled reactor-test module (HTR-10). The graphite properties used in the ceramic internals are provided, along with the results of an operating stress analysis of the graphite components and the metallic components. Satisfactory results were obtained for the machining and installation of the ceramic components and the stress analysis of the graphite and metallic components of HTR-10.

  7. Benchmark Evaluation of the HTR-PROTEUS Absorber Rod Worths (Core 4)

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    John D. Bess; Leland M. Montierth

    2014-06-01

    PROTEUS was a zero-power research reactor at the Paul Scherrer Institute (PSI) in Switzerland. The critical assembly was constructed from a large graphite annulus surrounding a central cylindrical cavity. Various experimental programs were investigated in PROTEUS; during the years 1992 through 1996, it was configured as a pebble-bed reactor and designated HTR-PROTEUS. Various critical configurations were assembled with each accompanied by an assortment of reactor physics experiments including differential and integral absorber rod measurements, kinetics, reaction rate distributions, water ingress effects, and small sample reactivity effects [1]. Four benchmark reports were previously prepared and included in the March 2013 edition of the International Handbook of Evaluated Reactor Physics Benchmark Experiments (IRPhEP Handbook) [2] evaluating eleven critical configurations. A summary of that effort was previously provided [3] and an analysis of absorber rod worth measurements for Cores 9 and 10 have been performed prior to this analysis and included in PROTEUS-GCR-EXP-004 [4]. In the current benchmark effort, absorber rod worths measured for Core Configuration 4, which was the only core with a randomly-packed pebble loading, have been evaluated for inclusion as a revision to the HTR-PROTEUS benchmark report PROTEUS-GCR-EXP-002.

  8. Physical Analysis of the Initial Core and Running-In Phase for Pebble-Bed Reactor HTR-PM

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    Jingyu Zhang

    2017-01-01

    Full Text Available The pebble-bed reactor HTR-PM is being built in China and is planned to be critical in one or two years. At present, one emphasis of engineering design is to determine the fuel management scheme of the initial core and running-in phase. There are many possible schemes, and many factors need to be considered in the process of scheme evaluation and analysis. Based on the experience from the constructed or designed pebble-bed reactors, the fuel enrichment and the ratio of fuel spheres to graphite spheres are important. In this paper, some relevant physical considerations of the initial core and running-in phase of HTR-PM are given. Then a typical scheme of the initial core and running-in phase is proposed and simulated with VSOP code, and some key physical parameters, such as the maximum power per fuel sphere, the maximum fuel temperature, the refueling rate, and the discharge burnup, are calculated. Results of the physical parameters all satisfy the relevant design requirements, which means the proposed scheme is safe and reliable and can provide support for the fuel management of HTR-PM in the future.

  9. Status of the experiment NACOK for investigations on the ingress of air into the core of an HTR-module

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    Schaaf, J.; Froehling, W.; Hohn, H. [Institute for Safety Research and Reactor Technology, Forschungszentrum Juelich, Juelich (Germany)

    1998-09-01

    Experimental investigations on the ingress of air into the core of an HTR can be divided into two categories: generic experiments, e.g. the measurement of material properties for the corrosion of specific graphite types with air to create data for the numerical calculation of air ingress accidents, and design related experiments, with the intention to investigate the course of an air ingress accident for a specific HTR design, under certain assumptions for the initiation of the accident. General safety discussions, but also the demand for catastrophe-free nuclear reactors require, that the computational predictions for the course of heavy accidents must be proven experimentally as realistic as possible, which leads in general to design related experiments. Therefore, the Forschungszentrum Juelich has set up an experimental facility to investigate for an HTR with the Siemens design the course and the local distribution of corrosion damages associated with an air ingress accident. The facility has been termed NACOK, which stands for NAtural COnvection in the core with Korrosion (i.e. the German word for corrosion). 4 refs.

  10. Recent advances on thermohydraulic simulation of HTR-10 nuclear reactor core using realistic CFD approach

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    Silva, Alexandro S., E-mail: alexandrossilva@ifba.edu.br [Instituto Federal de Educacao, Ciencia e Tecnologia da Bahia (IFBA), Vitoria da Conquista, BA (Brazil); Mazaira, Leorlen Y.R., E-mail: leored1984@gmail.com, E-mail: cgh@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas (INSTEC), La Habana (Cuba); Dominguez, Dany S.; Hernandez, Carlos R.G., E-mail: alexandrossilva@gmail.com, E-mail: dsdominguez@gmail.com [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil). Programa de Pos-Graduacao em Modelagem Computacional; Lira, Carlos A.B.O., E-mail: cabol@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2015-07-01

    High-temperature gas-cooled reactors (HTGRs) have the potential to be used as possible energy generation sources in the near future, owing to their inherently safe performance by using a large amount of graphite, low power density design, and high conversion efficiency. However, safety is the most important issue for its commercialization in nuclear energy industry. It is very important for safety design and operation of an HTGR to investigate its thermal-hydraulic characteristics. In this article, it was performed the thermal-hydraulic simulation of compressible flow inside the core of the pebble bed reactor HTR (High Temperature Reactor)-10 using Computational Fluid Dynamics (CFD). The realistic approach was used, where every closely packed pebble is realistically modelled considering a graphite layer and sphere of fuel. Due to the high computational cost is impossible simulate the full core; therefore, the geometry used is a FCC (Face Centered Cubic) cell with the half height of the core, with 21 layers and 95 pebbles. The input data used were taken from the thermal-hydraulic IAEA Bechmark. The results show the profiles of velocity and temperature of the coolant in the core, and the temperature distribution inside the pebbles. The maximum temperatures in the pebbles do not exceed the allowable limit for this type of nuclear fuel. (author)

  11. Thermohydraulic simulation of HTR-10 nuclear reactor core using realistic CFD approach; Simulacao termohidraulica do nucleo do reator nuclear HTR-10 com o uso da abordagem realistica CFD

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alexandro S.; Dominguez, Dany S., E-mail: alexandrossilva@gmail.com, E-mail: dsdominguez@gmail.com [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil); Mazaira, Leorlen Y. Rojas; Hernandez, Carlos R.G., E-mail: leored1984@gmail.com, E-mail: cgh@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas, La Habana (Cuba); Lira, Carlos Alberto Brayner de Oliveira, E-mail: cabol@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil)

    2015-07-01

    High-temperature gas-cooled reactors (HTGRs) have the potential to be used as possible energy generation sources in the near future, owing to their inherently safe performance by using a large amount of graphite, low power density design, and high conversion efficiency. However, safety is the most important issue for its commercialization in nuclear energy industry. It is very important for safety design and operation of an HTGR to investigate its thermal–hydraulic characteristics. In this article, it was performed the thermal–hydraulic simulation of compressible flow inside the core of the pebble bed reactor HTR (High Temperature Reactor)-10 using Computational Fluid Dynamics (CFD). The realistic approach was used, where every closely packed pebble is realistically modelled considering a graphite layer and sphere of fuel. Due to the high computational cost is impossible simulate the full core; therefore, the geometry used is a column of FCC (Face Centered Cubic) cells, with 41 layers and 82 pebbles. The input data used were taken from the thermohydraulic IAEA Benchmark (TECDOC-1694). The results show the profiles of velocity and temperature of the coolant in the core, and the temperature distribution inside the pebbles. The maximum temperatures in the pebbles do not exceed the allowable limit for this type of nuclear fuel. (author)

  12. A SMALL MODULAR REACTOR DESIGN FOR MULTIPLE ENERGY APPLICATIONS: HTR50S

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    X. YAN

    2013-06-01

    Full Text Available HTR50S is a small modular reactor system based on HTGR. It is designed for a triad of applications to be implemented in successive stages. In the first stage, a base plant for heat and power is constructed of the fuel proven in JAEA's 950°C, 30MWt test reactor HTTR and a conventional steam turbine to minimize development risk. While the outlet temperature is lowered to 750°C for the steam turbine, thermal power is raised to 50MWt by enabling 40% greater power density in 20% taller core than the HTTR. However the fuel temperature limit and reactor pressure vessel diameter are kept. In second stage, a new fuel that is currently under development at JAEA will allow the core outlet temperature to be raised to 900°C for the purpose of demonstrating more efficient gas turbine power generation and high temperature heat supply. The third stage adds a demonstration of nuclear-heated hydrogen production by a thermochemical process. A licensing approach to coupling high temperature industrial process to nuclear reactor will be developed. The low initial risk and the high longer-term potential for performance expansion attract development of the HTR50S as a multipurpose industrial or distributed energy source.

  13. The Preliminary GAMMA Code Thermal hydraulic Analysis for the Steady State of HTR-10 Initial Core

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    Jun, Ji Su; Lim, Hong Sik; Lee, Won Jae

    2006-07-15

    This report describes the preliminary thermalhydraulic analysis of HTR-10 steady state full power initial core to provide a benchmark calculation of VHTGR(Very High-Temperature Gas-Cooled Reactors) safety analysis code of GAMMA(GAs Multicomponent Mixture Analysis). The input data of GAMMA code are produced for the models of fluid block, wall block, radiation heat transfer and each component material properties in HTR-10 reactor. The temperature and flow distributions of HTR-10 steady state 10 MW{sub th} full power initial core are calculated by GAMMA code with boundary conditions of total reactor inlet flow rate of 4.32 kg/s, inlet temperature of 250 .deg. C, inlet pressure of 3 MPa, outlet pressure of 2.992 MPa and the fixed temperature at RCCS water cooling tube of 50 .deg C. The calculation results are compared with the measured solid material temperatures at 22 fixed instrumentation positions in HTR-10. The wall temperature distribution in pebble bed core shows that the minimum temperature of 358 .deg. C is located at upper core, a higher temperature zone than 829 .deg. C is located at the inner region of 0.45 m radius at the bottom of core centre, and the maximum wall temperature is 897 .deg. C. The wall temperatures linearly decreases at radially and axially farther side from the bottom of core centre. The maximum temperature of RPV is 230 .deg. C, and the maximum values of fuel average temperature and TRISO centreline temperature are 907 .deg. C and 929 .deg. C, respectively and they are much lower than the fuel temperature limitation of 1230 .deg. C. The comparsion between the GAMMA code predictions and the measured temperature data shows that the calculation results are very close to the measured values in top and side reflector region, but a great difference is appeared in bottom reflector region. Some measured data are abnormally high in bottom reflector region, and so the confirmation of data is necessary in future. Fifteen of twenty two data have a

  14. HTR-PROTEUS pebble bed experimental program cores 9 & 10: columnar hexagonal point-on-point packing with a 1:1 moderator-to-fuel pebble ratio

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    Bess, John D. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-03-01

    PROTEUS is a zero-power research reactor based on a cylindrical graphite annulus with a central cylindrical cavity. The graphite annulus remains basically the same for all experimental programs, but the contents of the central cavity are changed according to the type of reactor being investigated. Through most of its service history, PROTEUS has represented light-water reactors, but from 1992 to 1996 PROTEUS was configured as a pebble-bed reactor (PBR) critical facility and designated as HTR-PROTEUS. The nomenclature was used to indicate that this series consisted of High Temperature Reactor experiments performed in the PROTEUS assembly. During this period, seventeen critical configurations were assembled and various reactor physics experiments were conducted. These experiments included measurements of criticality, differential and integral control rod and safety rod worths, kinetics, reaction rates, water ingress effects, and small sample reactivity effects (Ref. 3). HTR-PROTEUS was constructed, and the experimental program was conducted, for the purpose of providing experimental benchmark data for assessment of reactor physics computer codes. Considerable effort was devoted to benchmark calculations as a part of the HTR-PROTEUS program. References 1 and 2 provide detailed data for use in constructing models for codes to be assessed. Reference 3 is a comprehensive summary of the HTR-PROTEUS experiments and the associated benchmark program. This document draws freely from these references. Only Cores 9 and 10 are evaluated in this benchmark report due to similarities in their construction. The other core configurations of the HTR-PROTEUS program are evaluated in their respective reports as outlined in Section 1.0. Cores 9 and 10 were evaluated and determined to be acceptable benchmark experiments.

  15. HTR-PROTEUS PEBBLE BED EXPERIMENTAL PROGRAM CORES 9 & 10: COLUMNAR HEXAGONAL POINT-ON-POINT PACKING WITH A 1:1 MODERATOR-TO-FUEL PEBBLE RATIO

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess

    2013-03-01

    PROTEUS is a zero-power research reactor based on a cylindrical graphite annulus with a central cylindrical cavity. The graphite annulus remains basically the same for all experimental programs, but the contents of the central cavity are changed according to the type of reactor being investigated. Through most of its service history, PROTEUS has represented light-water reactors, but from 1992 to 1996 PROTEUS was configured as a pebble-bed reactor (PBR) critical facility and designated as HTR-PROTEUS. The nomenclature was used to indicate that this series consisted of High Temperature Reactor experiments performed in the PROTEUS assembly. During this period, seventeen critical configurations were assembled and various reactor physics experiments were conducted. These experiments included measurements of criticality, differential and integral control rod and safety rod worths, kinetics, reaction rates, water ingress effects, and small sample reactivity effects (Ref. 3). HTR-PROTEUS was constructed, and the experimental program was conducted, for the purpose of providing experimental benchmark data for assessment of reactor physics computer codes. Considerable effort was devoted to benchmark calculations as a part of the HTR-PROTEUS program. References 1 and 2 provide detailed data for use in constructing models for codes to be assessed. Reference 3 is a comprehensive summary of the HTR-PROTEUS experiments and the associated benchmark program. This document draws freely from these references. Only Cores 9 and 10 are evaluated in this benchmark report due to similarities in their construction. The other core configurations of the HTR-PROTEUS program are evaluated in their respective reports as outlined in Section 1.0. Cores 9 and 10 were evaluated and determined to be acceptable benchmark experiments.

  16. The effects of applying silicon carbide coating on core reactivity of pebble-bed HTR in water ingress accident

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    Zuhair, S.; Setiadipura, Topan [National Nuclear Energy Agency of Indonesia, Serpong Tagerang Selatan (Indonesia). Center for Nuclear Reactor Technology and Safety; Su' ud, Zaki [Bandung Institute of Technology (Indonesia). Dept. of Physics

    2017-03-15

    Graphite is used as the moderator, fuel barrier material, and core structure in High Temperature Reactors (HTRs). However, despite its good thermal and mechanical properties below the radiation and high temperatures, it cannot avoid corrosion as a consequence of an accident of water/air ingress. Degradation of graphite as a main HTR material and the formation of dangerous CO gas is a serious problem in HTR safety. One of the several steps that can be adopted to avoid or prevent the corrosion of graphite by the water/air ingress is the application of a thin layer of silicon carbide (SiC) on the surface of the fuel element. This study investigates the effect of applying SiC coating on the fuel surfaces of pebble-bed HTR in water ingress accident from the reactivity points of view. A series of reactivity calculations were done with the Monte Carlo transport code MCNPX and continuous energy nuclear data library ENDF/B-VII at temperature of 1200 K. Three options of UO{sub 2}, PuO{sub 2}, and ThO{sub 2}/UO{sub 2} fuel kernel were considered to obtain the inter comparison of the core reactivity of pebble-bed HTR in conditions of water/air ingress accident. The calculation results indicated that the UO{sub 2}-fueled pebble-bed HTR reactivity was slightly reduced and relatively more decreased when the thickness of the SiC coating increased. The reactivity characteristic of ThO{sub 2}/UO{sub 2}-fueled pebble-bed HTR showed a similar trend to that of UO{sub 2}, but did not show reactivity peak caused by water ingress. In contrast with UO{sub 2}- and ThO{sub 2}-fueled pebble-bed HTR, although the reactivity of PuO{sub 2}-fueled pebble-bed HTR was the lowest, its characteristics showed a very high reactivity peak (0.33 Δk/k) and this introduction of positive reactivity is difficult to control. SiC coating on the surface of the plutonium fuel pebble has no significant impact. From the comparison between reactivity characteristics of uranium, thorium and plutonium cores with 0

  17. HTR-PROTEUS Pebble Bed Experimental Program Cores 1, 1A, 2, and 3: Hexagonal Close Packing with a 1:2 Moderator-to-Fuel Pebble Ratio

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    John D. Bess; Barbara H. Dolphin; James W. Sterbentz; Luka Snoj; Igor Lengar; Oliver Köberl

    2012-03-01

    In its deployment as a pebble bed reactor (PBR) critical facility from 1992 to 1996, the PROTEUS facility was designated as HTR-PROTEUS. This experimental program was performed as part of an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on the Validation of Safety Related Physics Calculations for Low Enriched HTGRs. Within this project, critical experiments were conducted for graphite moderated LEU systems to determine core reactivity, flux and power profiles, reaction-rate ratios, the worth of control rods, both in-core and reflector based, the worth of burnable poisons, kinetic parameters, and the effects of moisture ingress on these parameters. Four benchmark experiments were evaluated in this report: Cores 1, 1A, 2, and 3. These core configurations represent the hexagonal close packing (HCP) configurations of the HTR-PROTEUS experiment with a moderator-to-fuel pebble ratio of 1:2. Core 1 represents the only configuration utilizing ZEBRA control rods. Cores 1A, 2, and 3 use withdrawable, hollow, stainless steel control rods. Cores 1 and 1A are similar except for the use of different control rods; Core 1A also has one less layer of pebbles (21 layers instead of 22). Core 2 retains the first 16 layers of pebbles from Cores 1 and 1A and has 16 layers of moderator pebbles stacked above the fueled layers. Core 3 retains the first 17 layers of pebbles but has polyethylene rods inserted between pebbles to simulate water ingress. The additional partial pebble layer (layer 18) for Core 3 was not included as it was used for core operations and not the reported critical configuration. Cores 1, 1A, 2, and 3 were determined to be acceptable benchmark experiments.

  18. HTR-PROTEUS Pebble Bed Experimental Program Cores 1, 1A, 2, and 3: Hexagonal Close Packing with a 1:2 Moderator-to-Fuel Pebble Ratio

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess; Barbara H. Dolphin; James W. Sterbentz; Luka Snoj; Igor Lengar; Oliver Köberl

    2013-03-01

    In its deployment as a pebble bed reactor (PBR) critical facility from 1992 to 1996, the PROTEUS facility was designated as HTR-PROTEUS. This experimental program was performed as part of an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on the Validation of Safety Related Physics Calculations for Low Enriched HTGRs. Within this project, critical experiments were conducted for graphite moderated LEU systems to determine core reactivity, flux and power profiles, reaction-rate ratios, the worth of control rods, both in-core and reflector based, the worth of burnable poisons, kinetic parameters, and the effects of moisture ingress on these parameters. Four benchmark experiments were evaluated in this report: Cores 1, 1A, 2, and 3. These core configurations represent the hexagonal close packing (HCP) configurations of the HTR-PROTEUS experiment with a moderator-to-fuel pebble ratio of 1:2. Core 1 represents the only configuration utilizing ZEBRA control rods. Cores 1A, 2, and 3 use withdrawable, hollow, stainless steel control rods. Cores 1 and 1A are similar except for the use of different control rods; Core 1A also has one less layer of pebbles (21 layers instead of 22). Core 2 retains the first 16 layers of pebbles from Cores 1 and 1A and has 16 layers of moderator pebbles stacked above the fueled layers. Core 3 retains the first 17 layers of pebbles but has polyethylene rods inserted between pebbles to simulate water ingress. The additional partial pebble layer (layer 18) for Core 3 was not included as it was used for core operations and not the reported critical configuration. Cores 1, 1A, 2, and 3 were determined to be acceptable benchmark experiments.

  19. HTR-proteus pebble bed experimental program core 4: random packing with a 1:1 moderator-to-fuel pebble ratio

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    Bess, John D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Montierth, Leland M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sterbentz, James W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Briggs, J. Blair [Idaho National Lab. (INL), Idaho Falls, ID (United States); Gougar, Hans D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Snoj, Luka [Jozef Stefan Inst. (IJS), Ljubljana (Slovenia); Lengar, Igor [Jozef Stefan Inst. (IJS), Ljubljana (Slovenia); Koberl, Oliver [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    2014-03-01

    In its deployment as a pebble bed reactor (PBR) critical facility from 1992 to 1996, the PROTEUS facility was designated as HTR-PROTEUS. This experimental program was performed as part of an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on the Validation of Safety Related Physics Calculations for Low Enriched HTGRs. Within this project, critical experiments were conducted for graphite moderated LEU systems to determine core reactivity, flux and power profiles, reaction-rate ratios, the worth of control rods, both in-core and reflector based, the worth of burnable poisons, kinetic parameters, and the effects of moisture ingress on these parameters. One benchmark experiment was evaluated in this report: Core 4. Core 4 represents the only configuration with random pebble packing in the HTR-PROTEUS series of experiments, and has a moderator-to-fuel pebble ratio of 1:1. Three random configurations were performed. The initial configuration, Core 4.1, was rejected because the method for pebble loading, separate delivery tubes for the moderator and fuel pebbles, may not have been completely random; this core loading was rejected by the experimenters. Cores 4.2 and 4.3 were loaded using a single delivery tube, eliminating the possibility for systematic ordering effects. The second and third cores differed slightly in the quantity of pebbles loaded (40 each of moderator and fuel pebbles), stacked height of the pebbles in the core cavity (0.02 m), withdrawn distance of the stainless steel control rods (20 mm), and withdrawn distance of the autorod (30 mm). The 34 coolant channels in the upper axial reflector and the 33 coolant channels in the lower axial reflector were open. Additionally, the axial graphite fillers used in all other HTR-PROTEUS configurations to create a 12-sided core cavity were not used in the randomly packed cores. Instead, graphite fillers were placed on the cavity floor, creating a funnel-like base, to discourage ordering

  20. HTR-PROTEUS PEBBLE BED EXPERIMENTAL PROGRAM CORE 4: RANDOM PACKING WITH A 1:1 MODERATOR-TO-FUEL PEBBLE RATIO

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess; Leland M. Montierth

    2013-03-01

    In its deployment as a pebble bed reactor (PBR) critical facility from 1992 to 1996, the PROTEUS facility was designated as HTR-PROTEUS. This experimental program was performed as part of an International Atomic Energy Agency (IAEA) Coordinated Research Project (CRP) on the Validation of Safety Related Physics Calculations for Low Enriched HTGRs. Within this project, critical experiments were conducted for graphite moderated LEU systems to determine core reactivity, flux and power profiles, reaction-rate ratios, the worth of control rods, both in-core and reflector based, the worth of burnable poisons, kinetic parameters, and the effects of moisture ingress on these parameters. One benchmark experiment was evaluated in this report: Core 4. Core 4 represents the only configuration with random pebble packing in the HTR-PROTEUS series of experiments, and has a moderator-to-fuel pebble ratio of 1:1. Three random configurations were performed. The initial configuration, Core 4.1, was rejected because the method for pebble loading, separate delivery tubes for the moderator and fuel pebbles, may not have been completely random; this core loading was rejected by the experimenters. Cores 4.2 and 4.3 were loaded using a single delivery tube, eliminating the possibility for systematic ordering effects. The second and third cores differed slightly in the quantity of pebbles loaded (40 each of moderator and fuel pebbles), stacked height of the pebbles in the core cavity (0.02 m), withdrawn distance of the stainless steel control rods (20 mm), and withdrawn distance of the autorod (30 mm). The 34 coolant channels in the upper axial reflector and the 33 coolant channels in the lower axial reflector were open. Additionally, the axial graphite fillers used in all other HTR-PROTEUS configurations to create a 12-sided core cavity were not used in the randomly packed cores. Instead, graphite fillers were placed on the cavity floor, creating a funnel-like base, to discourage ordering

  1. Conceptual design of severe accident free HTR and related test program of HTTR

    Energy Technology Data Exchange (ETDEWEB)

    Kunitomi, Kazuhiko; Tachibana, Yukio; Saikusa, Akio; Sawa, Kazuhiro [Department of HTTR Project, Oarai Research Establishment, Japan Atomic Energy Research Institute JAERI, Ibaraki-ken (Japan)

    1998-09-01

    The SFHTR (Severe Accident Free HTR) is a prototype design for a next generation reactor. It is suitable for widespread deployment by virtue of its inherent safety features and very long refueling interval. Furthermore, its inherent safety features can be demonstrated by full scale tests. Many of these features may be demonstrated in the HTTR (High Temperature Engineering Test Reactor). The SFHTR is designed to have a probability of severe accident at least two orders lower than existing systems. The fuel will not exceed its failure temperature even in the event of complete loss of coolant or complete withdrawal of two control rods. A unique configuration of burnable poisons allows a fuel cycle of 16 years and a burnup exceeding 120 GWd/ton. This feature promises very high availability and good economics. We have designed two SFHTR systems. The larger one, the MSFHTR, has a 450-600 MW thermal capacity, and is intended for the production of hydrogen and electricity. The smaller SSFHTR is intended for remote areas, off the electrical grid, for simultaneous production of electricity and desalinated water. The SSFHTR can produce 23.5 MWe plus 40 ton/hr of water with a net efficiency of 47%. The HTTR is capable of conducting full scale simulation testing of key SFHTR design features, to confirm and extend the designs, and as a first step in convincing the public and the licensing authority of the validity of demonstrable inherent safety. This paper describes design features of a 50 MW SFHTR focusing on the safety concept, safety evaluation, and core design. 18 refs.

  2. HTR-Proteus Pebble Bed Experimental Program Cores 5,6,7,&8: Columnar Hexagonal Point-on-Point Packing with a 1:2 Moderator-to-Fuel Pebble Ratio

    Energy Technology Data Exchange (ETDEWEB)

    Bess, John D. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sterbentz, James W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Snoj, Luka [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lengar, Igor [Idaho National Lab. (INL), Idaho Falls, ID (United States); Koberl, Oliver [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    PROTEUS is a zero-power research reactor based on a cylindrical graphite annulus with a central cylindrical cavity. The graphite annulus remains basically the same for all experimental programs, but the contents of the central cavity are changed according to the type of reactor being investigated. Through most of its service history, PROTEUS has represented light-water reactors, but from 1992 to 1996 PROTEUS was configured as a pebble-bed reactor (PBR) critical facility and designated as HTR-PROTEUS. The nomenclature was used to indicate that this series consisted of High Temperature Reactor experiments performed in the PROTEUS assembly. During this period, seventeen critical configurations were assembled and various reactor physics experiments were conducted. These experiments included measurements of criticality, differential and integral control rod and safety rod worths, kinetics, reaction rates, water ingress effects, and small sample reactivity effects (Ref. 3). HTR-PROTEUS was constructed, and the experimental program was conducted, for the purpose of providing experimental benchmark data for assessment of reactor physics computer codes. Considerable effort was devoted to benchmark calculations as a part of the HTR-PROTEUS program. References 1 and 2 provide detailed data for use in constructing models for codes to be assessed. Reference 3 is a comprehensive summary of the HTR-PROTEUS experiments and the associated benchmark program. This document draws freely from these references. Only Cores 9 and 10 are evaluated in this benchmark report due to similarities in their construction. The other core configurations of the HTR-PROTEUS program are evaluated in their respective reports as outlined in Section 1.0. Cores 9 and 10 were evaluated and determined to be acceptable benchmark experiments.

  3. HTR-PROTEUS PEBBLE BED EXPERIMENTAL PROGRAM CORES 5, 6, 7, & 8: COLUMNAR HEXAGONAL POINT-ON-POINT PACKING WITH A 1:2 MODERATOR-TO-FUEL PEBBLE RATIO

    Energy Technology Data Exchange (ETDEWEB)

    John D. Bess

    2013-03-01

    PROTEUS is a zero-power research reactor based on a cylindrical graphite annulus with a central cylindrical cavity. The graphite annulus remains basically the same for all experimental programs, but the contents of the central cavity are changed according to the type of reactor being investigated. Through most of its service history, PROTEUS has represented light-water reactors, but from 1992 to 1996 PROTEUS was configured as a pebble-bed reactor (PBR) critical facility and designated as HTR-PROTEUS. The nomenclature was used to indicate that this series consisted of High Temperature Reactor experiments performed in the PROTEUS assembly. During this period, seventeen critical configurations were assembled and various reactor physics experiments were conducted. These experiments included measurements of criticality, differential and integral control rod and safety rod worths, kinetics, reaction rates, water ingress effects, and small sample reactivity effects (Ref. 3). HTR-PROTEUS was constructed, and the experimental program was conducted, for the purpose of providing experimental benchmark data for assessment of reactor physics computer codes. Considerable effort was devoted to benchmark calculations as a part of the HTR-PROTEUS program. References 1 and 2 provide detailed data for use in constructing models for codes to be assessed. Reference 3 is a comprehensive summary of the HTR-PROTEUS experiments and the associated benchmark program. This document draws freely from these references. Only Cores 9 and 10 are evaluated in this benchmark report due to similarities in their construction. The other core configurations of the HTR-PROTEUS program are evaluated in their respective reports as outlined in Section 1.0. Cores 9 and 10 were evaluated and determined to be acceptable benchmark experiments.

  4. Results of a Neutronic Simulation of HTR-Proteus Core 4.2 using PEBBED and other INL Reactor Physics Tools: FY-09 Report

    Energy Technology Data Exchange (ETDEWEB)

    Hans D. Gougar

    2009-08-01

    The Idaho National Laboratory’s deterministic neutronics analysis codes and methods were applied to the computation of the core multiplication factor of the HTR-Proteus pebble bed reactor critical facility. A combination of unit cell calculations (COMBINE-PEBDAN), 1-D discrete ordinates transport (SCAMP), and nodal diffusion calculations (PEBBED) were employed to yield keff and flux profiles. Preliminary results indicate that these tools, as currently configured and used, do not yield satisfactory estimates of keff. If control rods are not modeled, these methods can deliver much better agreement with experimental core eigenvalues which suggests that development efforts should focus on modeling control rod and other absorber regions. Under some assumptions and in 1D subcore analyses, diffusion theory agrees well with transport. This suggests that developments in specific areas can produce a viable core simulation approach. Some corrections have been identified and can be further developed, specifically: treatment of the upper void region, treatment of inter-pebble streaming, and explicit (multiscale) transport modeling of TRISO fuel particles as a first step in cross section generation. Until corrections are made that yield better agreement with experiment, conclusions from core design and burnup analyses should be regarded as qualitative and not benchmark quality.

  5. The experimental facility SEAT for investigations on the ingress of water into the core of an HTR-module

    Energy Technology Data Exchange (ETDEWEB)

    Leber, A.; Froehling, W.; Esser, F. [Institut fuer Sicherheitsforschung und Reaktortechnik, Forschungszentrum Juelich, Juelich (Germany)

    1998-09-01

    The ingress of water into the primary circuit of an HTR with steam cycle involves two different types of damage: corrosion and reactivity effects. The corrosion leads to the formation of water gas, which can explode under certain conditions, and the detrimental reactivity effect would be the formation of a positive reactivity coefficient, if a certain concentration of water in the core is exceeded. Both effects are dependent on the amount of water which is present within the graphite core structures, and therefore the water ingress is restricted by the reactor protection system to very low values. For the Siemens HTR-module, a moisture signal of {>=} 800 vpm equivalent to an ingress of 7kg water would lead to control rod insertion, blower shut down, closure of the steam generator valves and fast discharge of the steam generator. A continuation of the water ingress, e.g. through one or more broken steam generator tubes would require the failure of the reactor protection system, plus a continued operation of the feed water pumps. Therefore, accidents with long-lasting water and steam ingress into the primary circuit have to be considered as highly hypothetical. In a deterministic view however, such events can not be excluded, and investigations are necessary to create a solid basis for an assessment of these accidents. A further aim of the investigations is the search for passive acting counter measures to control the water ingress in such a manner, that catastrophic consequences can not occur. SEAT is the German abbreviation for self-acting removal of water droplets. 7 refs.

  6. Results of the Simulation of the HTR-Proteus Core 4.2 Using PEBBED-COMBINE: FY10 Report

    Energy Technology Data Exchange (ETDEWEB)

    Hans Gougar

    2010-07-01

    ABSTRACT The Idaho National Laboratory’s deterministic neutronics analysis codes and methods were applied to the computation of the core multiplication factor of the HTR-Proteus pebble bed reactor critical facility. This report is a follow-on to INL/EXT-09-16620 in which the same calculation was performed but using earlier versions of the codes and less developed methods. In that report, results indicated that the cross sections generated using COMBINE-7.0 did not yield satisfactory estimates of keff. It was concluded in the report that the modeling of control rods was not satisfactory. In the past year, improvements to the homogenization capability in COMBINE have enabled the explicit modeling of TRIS particles, pebbles, and heterogeneous core zones including control rod regions using a new multi-scale version of COMBINE in which the 1-dimensional discrete ordinate transport code ANISN has been integrated. The new COMBINE is shown to yield benchmark quality results for pebble unit cell models, the first step in preparing few-group diffusion parameters for core simulations. In this report, the full critical core is modeled once again but with cross sections generated using the capabilities and physics of the improved COMBINE code. The new PEBBED-COMBINE model enables the exact modeling of the pebbles and control rod region along with better approximation to structures in the reflector. Initial results for the core multiplication factor indicate significant improvement in the INL’s tools for modeling the neutronic properties of a pebble bed reactor. Errors on the order of 1.6-2.5% in keff are obtained; a significant improvement over the 5-6% error observed in the earlier This is acceptable for a code system and model in the early stages of development but still too high for a production code. Analysis of a simpler core model indicates an over-prediction of the flux in the low end of the thermal spectrum. Causes of this discrepancy are under investigation. New

  7. Temperature modeling for analysis and design of the sintering furnance in HTR fuel type of ball

    Energy Technology Data Exchange (ETDEWEB)

    Saragi, Elfrida [Computational Division, Centre for Nuclear Informatic Development, National Nuclear Energy Agency, Serpong 15310 (Indonesia); Setiadji, Moch [PTAPB - National Nuclear Energy Agency, Yogyakarta 1008 (Indonesia)

    2013-09-09

    One of the factors that determine the safety of the operation of the sintering furnace fuel HTR ball is the temperature distribution in the ceramic tube furnace. The temperature distribution must be determined at design stage. The tube has a temperature of 1600 °C at one end and about 40 °C at the other end. The outside of the tube was cooled by air through natural convection. The tube is a furnace ceramic tube which its geometry are 0.08, 0.09 and 0.5 m correspondingly for the inner tube diameter, outer tube diameter and tube length. The temperature distribution of the tube is determined by the natural convection coefficient (NCF), which is difficult to be calculated manually. The determination of NCF includes the Grasshoff, Prandtl, and Nusselt numbers which is a function of the temperature difference between the surrounding air with the ceramic tube. If the temperature vary along the tube, the complexity of the calculations increases. Thus the proposed modeling was performed to determine the temperature distribution along the tube and heat transfer coefficient using a self-developed software which permit the design process easier.

  8. Quantitative analysis of uncertainty from pebble flow in HTR

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Hao, E-mail: haochen.heu@163.com [Fundamental Science on Nuclear Safety and Simulation Technology Laboratory, College of Nuclear Science and Technology, Harbin Engineering University, Harbin (China); Institute of Nuclear and New Energy Technology (INET), Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing (China); Fu, Li; Jiong, Guo; Ximing, Sun; Lidong, Wang [Institute of Nuclear and New Energy Technology (INET), Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Tsinghua University, Beijing (China)

    2015-12-15

    Highlights: • An uncertainty and sensitivity analysis model for pebble flow has been built. • Experiment and random walk theory are used to identify uncertainty of pebble flow. • Effects of pebble flow to the core parameters are identified by sensitivity analysis. • Uncertainty of core parameters due to pebble flow is quantified for the first time. - Abstract: In pebble bed HTR, along the deterministic average flow lines, randomness exists in the flow of pebbles, which is not possible to simulate with the current reactor design codes for HTR, such as VSOP, due to the limitation of current computer capability. In order to study how the randomness of pebble flow will affect the key parameters in HTR, a new pebble flow model was set up, which has been successfully transplanted into the VSOP code. In the new pebble flow model, mixing coefficients were introduced into the fixed flow line to simulate the randomness of pebble flow. Numerical simulation and pebble flow experiments were facilitated to determine the mixing coefficients. Sensitivity analysis was conducted to achieve the conclusion that the key parameters of pebble bed HTR are not sensitive to the randomness in pebble flow. The uncertainty of maximum power density and power distribution caused by the randomness in pebble flow is very small, especially for the “multi-pass” scheme of fuel circulation adopted in the pebble bed HTR.

  9. Graphite Oxidation Simulation in HTR Accident Conditions

    Energy Technology Data Exchange (ETDEWEB)

    El-Genk, Mohamed

    2012-10-19

    Massive air and water ingress, following a pipe break or leak in steam-generator tubes, is a design-basis accident for high-temperature reactors (HTRs). Analysis of these accidents in both prismatic and pebble bed HTRs requires state-of-the-art capability for predictions of: 1) oxidation kinetics, 2) air helium gas mixture stratification and diffusion into the core following the depressurization, 3) transport of multi-species gas mixture, and 4) graphite corrosion. This project will develop a multi-dimensional, comprehensive oxidation kinetics model of graphite in HTRs, with diverse capabilities for handling different flow regimes. The chemical kinetics/multi-species transport model for graphite burning and oxidation will account for temperature-related changes in the properties of graphite, oxidants (O2, H2O, CO), reaction products (CO, CO2, H2, CH4) and other gases in the mixture (He and N2). The model will treat the oxidation and corrosion of graphite in geometries representative of HTR core component at temperatures of 900°C or higher. The developed chemical reaction kinetics model will be user-friendly for coupling to full core analysis codes such as MELCOR and RELAP, as well as computational fluid dynamics (CFD) codes such as CD-adapco. The research team will solve governing equations for the multi-dimensional flow and the chemical reactions and kinetics using Simulink, an extension of the MATLAB solver, and will validate and benchmark the model's predictions using reported experimental data. Researchers will develop an interface to couple the validated model to a commercially available CFD fluid flow and thermal-hydraulic model of the reactor , and will perform a simulation of a pipe break in a prismatic core HTR, with the potential for future application to a pebble-bed type HTR.

  10. NUCLEAR REACTOR CORE DESIGN

    Science.gov (United States)

    Mahlmeister, J.E.; Peck, W.S.; Haberer, W.V.; Williams, A.C.

    1960-03-22

    An improved core design for a sodium-cooled, graphitemoderated nuclear reactor is described. The improved reactor core comprises a number of blocks of moderator material, each block being in the shape of a regular prism. A number of channels, extending the length of each block, are disposed around the periphery. When several blocks are placed in contact to form the reactor core, the channels in adjacent blocks correspond with each other to form closed conduits extending the length of the core. Fuel element clusters are disposed in these closed conduits, and liquid coolant is forced through the annulus between the fuel cluster and the inner surface of the conduit. In a preferred embodiment of the invention, the moderator blocks are in the form of hexagonal prisms with longitudinal channels cut into the corners of the hexagon. The main advantage of an "edge-loaded" moderator block is that fewer thermal neutrons are absorbed by the moderator cladding, as compared with a conventional centrally loaded moderator block.

  11. Unbalance Compensation of a Full Scale Test Rig Designed for HTR-10GT: A Frequency-Domain Approach Based on Iterative Learning Control

    Directory of Open Access Journals (Sweden)

    Ying He

    2017-01-01

    Full Text Available Unbalance vibrations are crucial problems in heavy rotational machinery, especially for the systems with high operation speed, like turbine machinery. For the program of 10 MW High Temperature gas-cooled Reactor with direct Gas-Turbine cycle (HTR-10GT, the rated operation speed of the turbine system is 15000 RPM which is beyond the second bending frequency. In that case, even a small residual mass will lead to large unbalance vibrations. Thus, it is of great significance to study balancing methods for the system. As the turbine rotor is designed to be suspended by active magnetic bearings (AMBs, unbalance compensation could be achieved by adequate control strategies. In the paper, unbalance compensation for the Multi-Input and Multi-Output (MIMO active magnetic bearing (AMB system using frequency-domain iterative learning control (ILC is analyzed. Based on the analysis, an ILC controller for unbalance compensation of the full scale test rig, which is designed for the rotor and AMBs in HTR-10GT, is designed. Simulation results are reported which show the efficiency of the ILC controller for attenuating the unbalance vibration of the full scale test rig. This research can offer valuable design criterion for unbalance compensation of the turbine machinery in HTR-10GT.

  12. How to improve HTR`s appeal

    Energy Technology Data Exchange (ETDEWEB)

    Van Uitert, G.C. [Ministry of Economic Affairs, The Hague (Netherlands)

    1998-09-01

    After some initial success at the end of the sixties and in the seventies the development of the HTR (High-Temperature Reactor) stagnated in the eighties and nineties. The latter did some harm to HTR`s good reputation. As it is a well known strategy to build on success some arguments are in favour to base HTR`s further development on the older designs. This strategy has to some extent been followed in the Netherlands as the development of a small power design was preferred. In addition to a Technology Assessment, a pre-feasibility study was executed. Based on these activities a couple of pitfalls are exposed. The paper gives some guidelines how they might be overcome. With regard to the future attention is paid to which environmental, technical as well as public confidence problems may be faced. Finally, a prospect of HTR`s future role on energy production and especially electricity generation will be presented. 15 p.

  13. Toward full MOX core design

    Energy Technology Data Exchange (ETDEWEB)

    Rouviere, G.; Guillet, J.L. [Cogema BCR/DSDP, 78 - Saint Quentin en Yvelines (France); Bruna, G.B.; Pelet, J. [FRAMATOME, 92 - Paris-La-Defense (France)

    1999-07-01

    This paper presents a selection of the main preliminary results of a study program sponsored by COGEMA and currently carried out by FRAMATOME. The objective of this study is to investigate the feasibility of full MOX core loading in a French 1300 MWe PWR, a recent and widespread standard nuclear power plant. The investigation includes core nuclear design, thermal hydraulic and systems aspects. (authors)

  14. Survey of HTR related research at IRI, Delft, Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Hoogenboom, J.E.; Wallerbos, E.J.M.; Van der Hagen, T.H.J.J.; Van Dam, H. [Interfaculty Reactor Institute IRI, Delft University of Technology, Delft (Netherlands); Tuerkcan, E. [ECN Nuclear Research, Petten (Netherlands)

    1998-09-01

    High temperature helium-cooled reactors have a large potential for inherent safety. Therefore, several projects on HTR research are being carried out or were carried out at the Interfaculty Reactor Institute (IRI) of the Delft University of Technology in Delft, Netherlands. As part of a larger research programme measurements of core reactivity, reactivity worth of safety rods and of small samples being oscillated in the reactor core were carried out at the PROTEUS facility of the Paul Scherrer Institute at Villigen, Switzerland. Together with other partners in the Netherlands a small inherently safe co-generation plant with a pebble-bed HTR core was designed and analysed. It was verified that such a reactor can operate continuously for 10 years by adding continuously fuel pebbles until the maximum available core height is reached. As a new, innovative, inherently safe reactor type the design of a fluidized-bed reactor with coated fuel particles on a helium gas stream is discussed and results are shown for the analysis of inherent criticality safety under varying coolant flow rates. IRI is also taking part in the new IAEA Co-ordinated Research Programme, which involves participation in the start-up experiments of the Japanese HTTR and carrying out calculations for the core physics benchmark test. 11 refs.

  15. Scale analysis of decay heat removal system between HTR-10 and HTR-PM reactors under accidental conditions

    Energy Technology Data Exchange (ETDEWEB)

    Roberto, Thiago D.; Alvim, Antonio C.M. [Coordenacao de Pos-Graduacao e Pesquisa de Engenharia (PEN/COPPE/UFRJ), Rio de Janeiro, RJ (Brazil). Programa de Engenharia Nuclear; Lapa, Celso M.F., E-mail: thiagodbtr@gmail.com, E-mail: lapa@ien.gov.br, E-mail: alvim@nuclear.ufrj.br [Instituto de Engenharia Nuclear (IEN/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The 10 MW high-temperature gas-cooled test module (HTR-10) is a graphite-moderated and helium-cooled pebble bed reactor prototype that was designed to demonstrate the technical and safety feasibility of this type of reactor project under normal and accidental conditions. In addition, one of the systems responsible for ensuring the safe operation of this type of reactor is the passive decay heat removal system (DHRS), which operates using passive heat removal processes. A demonstration of the heat removal capacity of the DHRS under accidental conditions was analyzed based on a benchmark problem for design-based accidents on an HTR-10, i.e., the pressurized loss of forced cooling (PLOFC) described in technical reports produced by the International Atomic Energy Agency. In fact, the HTR-10 is also a proof-of-concept reactor for the high-temperature gas-cooled reactor pebble-bed module (HTR-PM), which generates approximately 25 times more heat than the HTR-10, with a thermal power of 250 MW, thereby requiring a DHRS with a higher system capacity. Thus, because an HTR-10 is a prototype reactor for an HTR-PM, a scaling analysis of the heat transfer process from the reactor to the DHRS was carried out between the HTR-10 and HTR-PM systems to verify the distortions of scale and the differences between the main dimensionless numbers from the two projects. (author)

  16. Requirements for HTR fuel particle design assessment; Specifications pour l'evaluation de la conception des particules combustibles des RHT

    Energy Technology Data Exchange (ETDEWEB)

    Chapelot, Ph.; Languille, A. [CEA Cadarache, 13 - Saint Paul lez Durance (France); Raepsaet, X. [CEA Saclay, 91 - Gif sur Yvette (France); Hittner, D. [FRAMATOME, 92 - Paris La Defence (France)

    2000-07-01

    In the framework of a large Research and Development programme devoted to High Temperature Reactors and set up in the CEA from 2000 on, we will address ourselves to the issue of coated fuel performance and design. Although HTR fuel main features have been established for a long time, we need today to reassess the fuel design to make sure that it meets the requirements linked to the most recent projects of High Temperature Reactors. Thus, in collaboration with Framatome and in connection with the Gas Turbine - Modular Helium Reactor (GT-MHR) international project, we are planning to perform parametric thermal and mechanical studies, regarding different particle design options (kernel diameter, layers composition and thicknesses) and seeking optima concerning particle leak-tightness and fission product retention. But to initiate such studies, we have first of all to define the requirements for HTR fuel, in terms of kernel composition (fissile element, oxide stoichiometry, enrichment), compact geometry (dimensions, particle volume fraction in the graphite matrix), power density, cooling gas temperature and irradiation conditions (burnup, fast fluence). (authors)

  17. Development of Chinese HTR-PM pebble bed equivalent conductivity test facility

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Cheng; Yang, Xingtuan; Jiang, Shengyao [Tsinghua Univ., Beijing (China). Inst. of Nuclear and New Energy Technology

    2016-01-15

    The first two 250-MWt high-temperature reactor pebble bed modules (HTR-PM) have been installing at the Shidaowan plant in Shandong Province, China. The values of the effective thermal conductivity of the pebble bed core are essential parameters for the design. For their determination, Tsinghua University in China has proposed a full-scale heat transfer experiment to conduct comprehensive thermal transfer tests in packed pebble bed and to determine the effective thermal conductivity.

  18. Status of the HTR programme in China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yuanhui H.; Sun, Yuliang [Institute of Nuclear Energy Technology, Tsinghua University, Beijing (China)

    1998-09-01

    The 10 MW High Temperature Gas-cooled Reactor-Test Module (HTR-10) is under construction at the Institute of Nuclear Energy Technology (INET), Beijing, China. The objective of the HTR-10 is to verify and demonstrate the technique and safety features of Modular HTGRs and to establish an experimental base for developing nuclear process heat application and closed gas turbine cycle. The construction of the reactor building has been reached to its top. The installation of primary and auxiliary systems will be started at the beginning of next year. It is expected to be critical in 1999. Some engineering experiments for technical support or verification for the HTR-10 design was and is being carried out, including experiments of the pulse pneumatic fuel handling system, hot gas duct, two phase flaw instability and control rods driving system, etc. Research and development of fuel elements have made great progress and fuel elements production will soon be started. 3 refs.

  19. Full MOX core design for PWR

    Energy Technology Data Exchange (ETDEWEB)

    Komano, Y.; Tochihara, H.; Ishida, M. [Mitsubishi Heavy Industries Ltd., Tokyo (Japan)

    1999-12-01

    Full MOX core design for APWR was analyzed in nuclear design, fuel integrity analysis, thermal hydraulic design and safety analysis et. al. Feasibility of Full MOX core was confirmed from these analyses without any large modifications. Full MOX PWR core has very good characteristics in which single Pu content in an assembly, burnable poison free, higher burnup and longer cycle operation are feasible. (author)

  20. Studi Optimasi Moderasi Neutron Dalam Teras Htr Pebble Bed

    OpenAIRE

    Zuhair, Zuhair; Suwoto, Suwoto; Irianto, Ign. Djoko

    2010-01-01

    STUDY ON OPTIMIZING NEUTRON MODERATION IN HTR PEBBLE-BED CORE. In HTR pebble bed, the neutron moderation is strongly influenced by the ratio of the fuel pebbles (F) and the moderator pebbles (M) contained in the reactor core. Optimum moderation can be achieved by adjusting the ratio F/M, but the combination of the pebble with the ratio of F/M more than 1:1 in pebble bed reactor core raises a problem in the calculation. This paper discusses a method to solve this problem. Optimizing neutron mo...

  1. Conceptual study of advanced PWR core design

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Chang, Moon Hee; Kim, Keung Ku; Joo, Hyung Kuk; Kim, Young Il; Noh, Jae Man; Hwang, Dae Hyun; Kim, Taek Kyum; Yoo, Yon Jong

    1997-09-01

    The purpose of this project is for developing and verifying the core design concepts with enhanced safety and economy, and associated methodologies for core analyses. From the study of the sate-of-art of foreign advanced reactor cores, we developed core concepts such as soluble boron free, high convertible and enhanced safety core loaded semi-tight lattice hexagonal fuel assemblies. To analyze this hexagonal core, we have developed and verified some neutronic and T/H analysis methodologies. HELIOS code was adopted as the assembly code and HEXFEM code was developed for hexagonal core analysis. Based on experimental data in hexagonal lattices and the COBRA-IV-I code, we developed a thermal-hydraulic analysis code for hexagonal lattices. Using the core analysis code systems developed in this project, we designed a 600 MWe core and studied the feasibility of the core concepts. Two additional scopes were performed in this project : study on the operational strategies of soluble boron free core and conceptual design of large scale passive core. By using the axial BP zoning concept and suitable design of control rods, this project showed that it was possible to design a soluble boron free core in 600 MWe PWR. The results of large scale core design showed that passive concepts and daily load follow operation could be practiced. (author). 15 refs., 52 tabs., 101 figs.

  2. Development of core design technology for LMR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Jin; Kim Young In; Kim, Young Il; Kim, Y. G.; Kim, S. J.; Song, H.; Kim, T. K.; Kim, W. S.; Hwang, W.; Lee, B. O.; Park, C. K.; Joo, H. K.; Yoo, J. W.; Kang, H. Y.; Park, W. S

    2000-05-01

    For the development of KALIMER (150 MWe) core conceptual design, design evolution and optimization for improved economics and safety enhancement was performed in the uranium metallic fueled equilibrium core design which uses U-Zr binary fuel not in excess of 20 percent enrichment. Utilizing results of the uranium ,metallic fueled core design, the breeder equilibrium core design with breeding ratio being over 1.1 was developed. In addition, utilizing LMR's excellent neutron economy, various core concepts for minor actinide burnup, inherent safety, economics and non-proliferation were realized and its optimization studies were performed. A code system for the LMR core conceptual design has been established through the implementation of needed functions into the existing codes and development of codes. To improve the accuracy of the core design, a multi-dimensional nodal transport code SOLTRAN, a three-dimensional transient code analysis code STEP, MATRA-LMR and ASSY-P for T/H analysis are under development. Through the automation of design calculations for efficient core design, an input generator and several interface codes have been developed. (author)

  3. How Cultural Knowledge Shapes Core Design Thinking

    DEFF Research Database (Denmark)

    Clemmensen, Torkil; Ranjan, Apara; Bødker, Mads

    2017-01-01

    The growing trend of co-creation and co-design in cross-cultural design teams presents challenges for the design thinking process. We integrate two frameworks, one on reasoning patterns in design thinking, the other on the dynamic constructivist theory of culture, to propose a situation specific ...... core design thinking in specific situations....

  4. Design Principles for Synthesizable Processor Cores

    DEFF Research Database (Denmark)

    Schleuniger, Pascal; McKee, Sally A.; Karlsson, Sven

    2012-01-01

    As FPGAs get more competitive, synthesizable processor cores become an attractive choice for embedded computing. Currently popular commercial processor cores do not fully exploit current FPGA architectures. In this paper, we propose general design principles to increase instruction throughput...... on FPGA-based processor cores: first, superpipelining enables higher-frequency system clocks, and second, predicated instructions circumvent costly pipeline stalls due to branches. To evaluate their effects, we develop Tinuso, a processor architecture optimized for FPGA implementation. We demonstrate...... through the use of micro-benchmarks that our principles guide the design of a processor core that improves performance by an average of 38% over a similar Xilinx MicroBlaze configuration....

  5. An HTR cogeneration system for industrial application

    Energy Technology Data Exchange (ETDEWEB)

    Haverkate, B.R.W.; Van Heek, A.I. [Plant Performance and Technology, Nuclear Research and Consultancy Group NRG, Petten (Netherlands); Kikstra, J.F. [Thermal Power Engineering, Faculty of Mechanical Engineering, Delft University of Technology, Delft (Netherlands)

    1999-01-01

    Because of its favourable characteristics of safety and simplicity the high-temperature reactor (HTR) could become a competitive heat source for a cogeneration unit. The Netherlands is a world leading country in the field of cogeneration. As nuclear energy remains an option for the medium and long term in this country, systems for nuclear cogeneration should be explored and developed. Hence, ECN Nuclear Research is developing a conceptual design of an HTR for Combined generation of Heat and Power (CHP) for the industry in and outside the Netherlands. The design of this small CHP-unit for industrial applications is mainly based on a pre-feasibility study in 1996, performed by a joint working group of five Dutch organisations, in which technical feasibility was shown. The concept that was subject of that study, INCOGEN, used a 40 MW thermal pebble bed HTR and produced a maximum amount of electricity plus low temperature heat. The system has been improved to produce industrial quality heat, and has been renamed ACACIA. The output of this installation is 14 MW electricity and 17 tonnes of steam per hour, with a pressure of 10 bar and a temperature of 220C. The economic characteristics of this installation turned out to be much more favourable using modern cost data. 15 refs.

  6. Core design and fuel management studies

    Energy Technology Data Exchange (ETDEWEB)

    Min, Byung Joo [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of); Chan, P. [Atomic Energy of Canada Ltd., Chalk River, ON (Canada)

    1997-06-01

    The design target for the CANDU 9 requires a 20% increase in electrical power output from an existing 480-channel CANDU core. Assuming a net electrical output of 861 MW(e) for a natural uranium fuelled Bruce-B/Darlington reactor in a warm water site, the net electrical output of the reference CANDU 9 reactor would be 1033 MW(e). This report documents the result of the physics studies for the design of the CANDU 9 480/SEU core. The results of the core design and fuel management studies of the CANDU 9 480/SEU reactor indicated that up to 1033 MW(e) output can be achieved in a 480-channel CANDU core by using SEU core can easily be maintained indefinitely using an automated refuelling program. Fuel performance evaluation based on the data of the 500 FPDs refuelling simulation concluded that SEU fuel failure is not expected. (author). 2 tabs., 38 figs., 5 refs.

  7. Full MOX core design for advanced PWR

    Energy Technology Data Exchange (ETDEWEB)

    Tochihara, H.; Komano, Y.; Ishida, M.; Mukai, H. [Mitsubishi Heavy Industries, Ltd., Yokohama (Japan)

    1995-12-31

    A full MOX core is an attractive option for large consumption of the recycled plutonium from reprocessed LWR fuel. The feasibility is verified of a full MOX core in a PWR with only small hardware modifications. The advanced PWR has been selected for this purpose. The full MOX core is feasible by increasing the number of control rods and adopting the enriched {sup 10}B in the soluble boron of reactor coolant system. The full MOX cores can be designed using one Pu` content per assembly and without any burnable absorbers. (author) 2 refs.

  8. Assessment of the HPLWR thermal core design

    Energy Technology Data Exchange (ETDEWEB)

    Schulenberg, T. [Karlsruhe Inst. of Tech., Karlsruhe (Germany); Maraczy, C. [Hungarian Academy of Sciences KFKI, Budapest (Hungary); Bernnat, W.; Starflinger, J. [Univ. of Stuttgart, IKE (Germany)

    2011-07-01

    The core design concept of the High Performance Light Water Reactor features a thermal neutron spectrum, provided by additional moderator water in water boxes and in gaps between assembly boxes, and a heat-up of the coolant in three steps from 280{sup o}C to 500{sup o}C. Intermediate coolant mixing has been foreseen by mixing chambers underneath and above the core to overcome the hot channel issue of a core design with a large enthalpy rise. The paper summarizes the various analyses performed within the project HPLWR-Phase 2 with respect to this core design and assesses how far the initial design target has been met. (author)

  9. HtrA3 stromal expression is correlated with tumor budding in stage II colorectal cancer.

    Science.gov (United States)

    Forse, Catherine L; Rahimi, Mahdi; Diamandis, Eleftherios P; Assarzadegan, Naziheh; Dawson, Heather; Grin, Andrea; Kennedy, Erin; O'Connor, Brenda; Messenger, David E; Riddell, Robert H; Kirsch, Richard; Karagiannis, George S

    2017-08-01

    Tumor budding is a well-established adverse prognostic factor in colorectal carcinoma (CRC). It may represent a form of epithelial-to-mesenchymal transition (EMT), although the underlying mechanisms remain unclear. High-temperature requirement A3 (HtrA3) is an inhibitor of the bone morphogenetic protein pathway, the suppression of which has been linked to EMT. Since HtrA3 is highly expressed in the desmoplastic stroma at the CRC invasive front, we sought to evaluate the relationship between tumor budding and HtrA3 expression in 172 stage II CRC resection specimens. All tumors were evaluated for tumor budding, with the highest budding slide selected for pan-keratin (CK) and HtrA3 immunohistochemistry. Representative areas of tumor core and invasive front, including budding and non-budding areas, were marked on CK stained slides, and then evaluated on HtrA3 stained slides. HtrA3 expression in tumor cells (tHtrA3) and peritumoral stroma (sHtrA3) was assessed for staining percentage and intensity (the product yielding a final score). Tumors with high-grade tumor budding (HGTB) showed increased expression of sHtrA3 in budding areas compared to non-budding areas at the invasive front (Ptumors compared to minimally budding tumors (Ptumor core (but not invasive front) was significantly associated with decreased 5-year overall survival on univariate analysis (P<0.05), but not multivariate analysis. HtrA3 expression in the peritumoral stroma of patients with stage II CRC is associated with HGTB and may be a novel marker of poor outcome. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Full MOX core design for KNGR

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Y. S.; Kim, Y. H.; Lee, K. H. [KEPRI, Taejon (Korea, Republic of)

    1999-10-01

    Nuclear design of KNGR(Korean Next Generation Reactor) is performed to evaluate the feasibility of full MOX(Mixed Oxide, PuO{sub 2}-UO{sub 2}) fuel loading in KNGR core. The reactor core is designed to produce 3983 MWth fission power, 3-batch, 18-month cycle length and Low Leakage Loading Pattern scheme with minimal change in NSSS designs optimized for UO{sub 2} fuel. A hybrid CEA configuration, 50% enriched boron in chemical shim, 5% enriched UO{sub 2} fuel in burnable poison rod have been adopted to guarantee the required shutdown margin and satisfy MSLB accident requirement.

  11. The family of Deg/HtrA proteases in plants

    Directory of Open Access Journals (Sweden)

    Schuhmann Holger

    2012-04-01

    Full Text Available Abstract Background The Deg/HtrA family of ATP-independent serine endopeptidases is present in nearly all organisms from bacteria to human and vascular plants. In recent years, multiple deg/htrA protease genes were identified in various plant genomes. During genome annotations most proteases were named according to the order of discovery, hence the same names were sometimes given to different types of Deg/HtrA enzymes in different plant species. This can easily lead to false inference of individual protease functions based solely on a shared name. Therefore, the existing names and classification of these proteolytic enzymes does not meet our current needs and a phylogeny-based standardized nomenclature is required. Results Using phylogenetic and domain arrangement analysis, we improved the nomenclature of the Deg/HtrA protease family, standardized protease names based on their well-established nomenclature in Arabidopsis thaliana, and clarified the evolutionary relationship between orthologous enzymes from various photosynthetic organisms across several divergent systematic groups, including dicots, a monocot, a moss and a green alga. Furthermore, we identified a “core set” of eight proteases shared by all organisms examined here that might provide all the proteolytic potential of Deg/HtrA proteases necessary for a hypothetical plant cell. Conclusions In our proposed nomenclature, the evolutionarily closest orthologs have the same protease name, simplifying scientific communication when comparing different plant species and allowing for more reliable inference of protease functions. Further, we proposed that the high number of Deg/HtrA proteases in plants is mainly due to gene duplications unique to the respective organism.

  12. Nuclear cogeneration based on HTR technology

    Energy Technology Data Exchange (ETDEWEB)

    Van Heek, A.I.; Haverkate, B.R.W. [Netherlands Energy Research Foundation ECN, Petten (Netherlands)

    1998-09-01

    Since 1993, activities on the development of high temperature reactors (HTR) are being undertaken in The Netherlands. After a general investigation of the available reactor concepts, and a familiarisation period to gain expertise on the different calculational methods for simulation of this reactor type, five partner companies and institutions focused their efforts on a small heat and power cogeneration system with an HTR as heat source, INCOGEN. At the same time, work on a number of selected HTR topics like waste management and vessel stress assessment has continued. Besides this, we participate in three IAEA Co-ordinated Research Programs. EW and JRC Petten participate in a Concerted Action on HTR technology, supported by the European Union. Finally, two bilateral co-operative activities with Germany and South-Africa complete the list. Based on an estimated market demand a 40 MWth basis configuration for the INCOGEN heat and power cogeneration plant was identified. Of this plant concept many aspects have been researched. Calculational analyses of the pebble fuel and reactor behaviour during normal operation and accident scenarios have been made. Plant lay-out has been worked out in more detail. The energy conversion system with helium turbine has been designed and simulated to assess its thermodynamic performance. Auxiliary systems and inspection and maintenance aspects are studied. Licensing has received a lot of attention: national and foreign licensing experience has been analysed and a listing of IAEA rules to be amended has been produced. Possible markets for the INCOGEN installation are identified and analysed. The economic assessment concluded that energy prices of this basis configuration of INCOGEN would be too high for The Netherlands on this moment, but this may turn out differently for other, more remote parts of the world. The study has been concluded with a number of recommendations for future efforts. Future plans include continuation of the

  13. Conceptual Models Core to Good Design

    CERN Document Server

    Johnson, Jeff

    2011-01-01

    People make use of software applications in their activities, applying them as tools in carrying out tasks. That this use should be good for people--easy, effective, efficient, and enjoyable--is a principal goal of design. In this book, we present the notion of Conceptual Models, and argue that Conceptual Models are core to achieving good design. From years of helping companies create software applications, we have come to believe that building applications without Conceptual Models is just asking for designs that will be confusing and difficult to learn, remember, and use. We show how Concept

  14. The R&D of HTGR high temperature helium sampling loop: From HTR-10 to HTR-PM

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Chao, E-mail: fangchao@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Advanced Nuclear Energy Technology, Tsinghua University, Beijing 100084 (China); The Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); Bao, Xuyin; Yang, Chen; Yang, Yanran; Cao, Jianzhu [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Collaborative Innovation Center of Advanced Nuclear Energy Technology, Tsinghua University, Beijing 100084 (China); The Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China)

    2016-09-15

    A High Temperature Helium Sampling Loop (HTHSL) for studying the transportation (deposition) behavior and total amount of solid fission products in high-temperature helium coming from the steam generator (SG) in the 10 MW High Temperature Gas-cooled Test Reactor (HTR-10) and High Temperature Reactor-Pebble bed Modules (HTR-PM) are researched and designed, respectively. Through the optimal design and simulation based on thermohydraulics analysis, the three-sleeve structure of deposition sampling device (DSD) could realize full-length temperature control evenly so that it could be used to study fission products in the primary circuit of HTR-10. On the other hand, an improved DSD is also designed for HTR-PM based on corresponding simulations, which could be used to sample the important nuclei in the high temperature helium from SG. These schemes offer two different methods to obtain the original source term in the high temperature helium, which will provide deeper understanding for the analysis of source terms of HTGR.

  15. SMART core preliminary nuclear design-II

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jeong Chan; Ji, Seong Kyun; Chang, Moon Hee

    1997-06-01

    Three loading patterns for 330 MWth SMART core are constructed for 25, 33 and 29 CRDMs, and one loading pattern for larger 69-FA core with 45 CRDMs is also constructed for comparison purpose. In this study, the core consists of 57 reduced height Korean Optimized Fuel Assemblies (KOFAs) developed by KAERI. The enrichment of fuel is 4.95 w/o. As a main burnable poison, 35% B-10 enriched B{sub 4}C-Al{sub 2}O{sub 3} shim is used. To control stuck rod worth, some gadolinia bearing fuel rods are used. The U-235 enrichment of the gadolinia bearing fuel rods is 1.8 w/o as used in KOFA. All patterns return cycle length of about 3 years. Three loading patterns except 25-CRDM pattern satisfy cold shutdown condition of keff {<=} 0.99 without soluble boron. These three patterns also satisfy the refueling condition of keff {<=} 0.95. In addition to the construction of loading pattern, an editing module of MASTER PPI files for rod power history generation is developed and rod power histories are generated for 29-CRDM loading pattern. Preliminary Fq design limit is suggested as 3.71 based on KOFA design experience. (author). 9 tabs., 45 figs., 16 refs.

  16. Multimedia foundations core concepts for digital design

    CERN Document Server

    Costello, Vic; Youngblood, Susan

    2012-01-01

    Understand the core concepts and skills of multimedia production and digital storytelling using text, graphics, photographs, sound, motion, and video. Then, put it all together using the skills that you have developed for effective project planning, collaboration, visual communication, and graphic design. Presented in full color with hundreds of vibrant illustrations, Multimedia Foundations trains you in the principles and skill sets common to all forms of digital media production, enabling you to create successful, engaging content, no matter what tools you are using. Companion website

  17. Development of core design and analyses technology for integral reactor

    Energy Technology Data Exchange (ETDEWEB)

    Zee, Sung Quun; Lee, C. C.; Song, J. S. and others

    1999-03-01

    Integral reactors are developed for the applications such as sea water desalination, heat energy for various industries, and power sources for large container ships. In order to enhance the inherent and passive safety features, low power density concept is chosen for the integral reactor SMART. Moreover, ultra-longer cycle and boron-free operation concepts are reviewed for better plant economy and simple design of reactor system. Especially, boron-free operation concept brings about large difference in core configurations and reactivity controls from those of the existing large size commercial nuclear power plants and also causes many differences in the safety aspects. The ultimate objectives of this study include detailed core design of a integral reactor, development of the core design system and technology, and finally acquisition of the system design certificate. The goal of the first stage is the conceptual core design, that is, to establish the design bases and requirements suitable for the boron-free concept, to develop a core loading pattern, to analyze the nuclear, thermal and hydraulic characteristics of the core and to perform the core shielding design. Interface data for safety and performance analyses including fuel design data are produced for the relevant design analysis groups. Nuclear, thermal and hydraulic, shielding design and analysis code systems necessary for the core conceptual design are established through modification of the existing design tools and newly developed methodology and code modules. Core safety and performance can be improved by the technology development such as boron-free core optimization, advaned core monitoring and operational aid system. Feasiblity study on the improvement of the core protection and monitoring system will also contribute toward core safety and performance. Both the conceptual core design study and the related technology will provide concrete basis for the next design phase. This study will also

  18. New Designs for NMR Core Scanning

    Science.gov (United States)

    Bluemich, B.; Anferova, S.; Talnishnikh, E.; Arnold, J.; Clauser, C.

    2006-12-01

    Within the last ten years, mobile magnetic resonance has moved from the oil field to many new areas of application. While the focus of mobile NMR in the past was on single-sided or inside-out NMR, the advent of tube-shaped Halbach magnets has introduced the conventional outside-in NMR concept to mobile NMR where the object is inside a magnet. Our Halbach magnet is constructed from small magnet blocks at light weight and low cost with a magnetic field sufficiently homogeneous. To automatize NMR measurements, the Halbach magnet is mounted on a sliding table to scan long core sections without human interaction. In homogeneous magnetic fields, the longitudinal relaxation time T1 and even the transverse relaxation time T2 are proportional to the pore diameters of rocks. Hence, the T1 and T2 signals map the pore-size distribution of the studied rock cores. For fully saturated samples the integral of the distribution curve is proportional to porosity. The porosity values from NMR measurements with the Halbach magnet are used to estimate permability. The Halbach magnet can be used for certain sample geometries in combination with exchangeable radio frequency (rf) coils with different diameters from 24 mm up to 80 mm. To measure standard Ocean Drilling Program (ODP)/Integrated Ocean Drilling Program (IODP) cores, which have a standard diameter of 60 mm and are split lengthwise after recovery, we use a surface figure-8 rf coil with an inner diameter of 60 mm. Besides 1D T2 measurements, we perform relaxation-relaxation correlation experiments, where T1 and T2 are measured in parallel. In this way, the influence of diffusion on the shape of the T2 distribution function is probed. A gradient coil system was designed to perform Pulsed Field Gradients (PFG) experiments. As the gradient coils restrict the axial access to the magnet, only cylindrical core plugs with 20 mm in diameter can be analysed by PFG NMR methods. The homogeneity of the magnetic field in the sensitive volume

  19. Magnetic Properties of Electrical Steel, Power Transformer Core Losses and Core Design Concepts

    OpenAIRE

    Freitag, Christian

    2017-01-01

    The work presented in this PhD-thesis includes the measurement of electrical steel's properties as well as the simulation of power transformer core losses and leads to the investigation of new core design methods.

  20. Learn from the Core--Design from the Core

    Science.gov (United States)

    Ockerse, Thomas

    2012-01-01

    The current objective, object-oriented approach to design is questioned along with design education viewed as a job-oriented endeavor. Instead relational knowledge and experience in a holistic sense, both tacit and explicit, are valued along with an appreciation of the unique character of the student. A new paradigm for design education is…

  1. Turbo decoder core design for system development

    Science.gov (United States)

    Chen, Xiaoyi; Yao, Qingdong; Liu, Peng

    2003-04-01

    use sliding-window version of the turbo decoder to reduce the memory requirements. This is also true in our design. In addition of this, a new method is adopted to expand the sliding window length but without increasing the storing requirement. This method also improves the performance evidently. The technologies adoped in the paper are suited hardware design for wireless application. For example, this decoding core can be embedded into our 32-bit digital signal processor (MD-32) to realize 3G basestation receiver.

  2. Final Report on Utilization of TRU TRISO Fuel as Applied to HTR Systems Part I: Pebble Bed Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Brian Boer; Abderrafi M. Ougouag

    2011-03-01

    significant failure is to be expected for the reference fuel particle during normal operation. It was found, however, that the sensitivity of the coating stress to the CO production in the kernel was large. The CO production is expected to be higher in DB fuel than in UO2 fuel, but its exact level has a high uncertainty. Furthermore, in the fuel performance analysis transient conditions were not yet taken into account. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge burnup level, while retaining its inherent safety characteristics. Using generic pebble bed reactor cores, this task will perform physics calculations to evaluate the capabilities of the pebble bed reactor to perform utilization and destruction of LWR used-fuel transuranics. The task will use established benchmarked models, and will introduce modeling advancements appropriate to the nature of the fuel considered (high transuranic [TRU] content and high burn-up). Accomplishments of this work include: •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Uranium. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Modified Open Cycle Components. •Core analysis of a HTR-MODULE design loaded with Deep-Burn fuel and Americium targets.

  3. Characterization of htrB and msbB mutants of the light organ symbiont Vibrio fischeri.

    Science.gov (United States)

    Adin, Dawn M; Phillips, Nancy J; Gibson, Bradford W; Apicella, Michael A; Ruby, Edward G; McFall-Ngai, Margaret J; Hall, Daniel B; Stabb, Eric V

    2008-02-01

    Bacterial lipid A is an important mediator of bacterium-host interactions, and secondary acylations added by HtrB and MsbB can be critical for colonization and virulence in pathogenic infections. In contrast, Vibrio fischeri lipid A stimulates normal developmental processes in this bacterium's mutualistic host, Euprymna scolopes, although the importance of lipid A structure in this symbiosis is unknown. To further examine V. fischeri lipid A and its symbiotic function, we identified two paralogs of htrB (designated htrB1 and htrB2) and an msbB gene in V. fischeri ES114 and demonstrated that these genes encode lipid A secondary acyltransferases. htrB2 and msbB are found on the Vibrio "housekeeping" chromosome 1 and are conserved in other Vibrio species. Mutations in htrB2 and msbB did not impair symbiotic colonization but resulted in phenotypic alterations in culture, including reduced motility and increased luminescence. These mutations also affected sensitivity to sodium dodecyl sulfate, kanamycin, and polymyxin, consistent with changes in membrane permeability. Conversely, htrB1 is located on the smaller, more variable vibrio chromosome 2, and an htrB1 mutant was wild-type-like in culture but appeared attenuated in initiating the symbiosis and was outcompeted 2.7-fold during colonization when mixed with the parent. These data suggest that htrB2 and msbB play conserved general roles in vibrio biology, whereas htrB1 plays a more symbiosis-specific role in V. fischeri.

  4. DIRSIG 5: core design and implementation

    Science.gov (United States)

    Goodenough, Adam A.; Brown, Scott D.

    2012-06-01

    The Digital Imaging and Remote Sensing Image Generation (DIRSIG) model has been developed at the Rochester Institute of Technology (RIT) for over two decades. The last major update of the model, DIRSIG 4, built on an established, first-principles, multi- and hyper-spectral scene simulation tool. It introduced a modern and flexible software architecture to support new sensor modalities and more complex and dynamic scenes. Since that time, the needs of the user community have grown and diversified in tandem with the computational capabilities of modern hardware. Faced with a desire to model more complex, multi-component systems that are beyond the original intent and capabilities of an aging software design, a new version of DIRSIG, version 5, is being introduced to the community. This paper describes the core of DIRSIG 5 that is responsible for linking the disparate sensor, scene, and environmental models together, spatially, temporally, and parametrically. The spatial relationships are governed by a planet-centric universe model encompassing a whole globe digital elevation and optical property model, the scene model(s), globally varying atmospheric models, and a space model. Temporal relationships are driven by a formal modeling and simulation architecture based on approaches used in engineering and biological sciences to model highly dynamic and interactive systems. Finally, the parametric interfaces are described by a universal data model that facilitates scripting, inter-dependent properties and user interface construction. The design of these components will be presented along with specific module implementation details. These simulation tools will be used to demonstrate some of the new capabilities and applications of DIRSIG 5.

  5. Computer-Aided Test Flow in Core-Based Design

    NARCIS (Netherlands)

    Zivkovic, V.; Tangelder, R.J.W.T.; Kerkhoff, Hans G.

    2000-01-01

    This paper copes with the efficient test-pattern generation in a core-based design. A consistent Computer-Aided Test (CAT) flow is proposed based on the required core-test strategy. It generates a test-pattern set for the embedded cores with high fault coverage and low DfT area overhead. The CAT

  6. Conceptual design of KALIMER uranium metallic fueled core

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young In; Kim, Sang Ji; Kim, Young Gyun; Kim, Young Jin

    1999-03-15

    As a part of the core design development of KALIMER(150 MWe), the KALIMER core design which uses U-Zr binary fuel not in excess of 20% enrichment was performed. Starting from the former uranium metallic fueled core design, a more economic and safer equilibrium core design was first established based on extensive researches for the possible enrichment gains over various design options and in-core fuel management strategies. Further optimization to extend fuel discharge burnup has been achieved by employing strategic loading schemes for initial and transition cycles to reach the equilibrium cycle early. The core performance analysis based on a once-through equilibrium fuel cycle scenario shows that the core has an average breeding ratio of 0.67 and core average discharge burnup of 61.6 MWD/kg. The negative sodium void reactivity over the core shows a beneficial potential to assure inherent safety characteristics. When comparing with conventional plutonium metallic fueled cores of the same power level, the present KALIMER uranium metallic fueled core has an increased physical core size to meet the enrichment restriction, and, as a result, a lower power density to realize the minimum one-year cycle operation. The KALIMER uranium metallic fueled core characterized by its negative sodium void reactivity and low power density can be operated with maximizing its core safety characteristics as a first generation LMR. The present uranium metallic fueled core allows an easy replacement with different fuel compositions by its demands, with the accumulation of operation experience and design data verification. (author). 34 refs., 34 tabs., 12 figs.

  7. First results for fluid dynamics, neutronics and fission product behavior in HTR applying the HTR code package (HCP) prototype

    Energy Technology Data Exchange (ETDEWEB)

    Allelein, H.-J., E-mail: h.j.allelein@fz-juelich.de [Forschungszentrum Jülich, 52425 Jülich (Germany); Institute for Reactor Safety and Reactor Technology, RWTH Aachen University, 52064 Aachen (Germany); Kasselmann, S.; Xhonneux, A.; Tantillo, F.; Trabadela, A.; Lambertz, D. [Forschungszentrum Jülich, 52425 Jülich (Germany)

    2016-09-15

    To simulate the different aspects of High Temperature Reactor (HTR) cores, a variety of specialized computer codes have been developed at Forschungszentrum Jülich (IEK-6) and Aachen University (LRST) in the last decades. In order to preserve knowledge, to overcome present limitations and to make these codes applicable to modern computer clusters, these individual programs are being integrated into a consistent code package. The so-called HTR code package (HCP) couples the related and recently applied physics models in a highly integrated manner and therefore allows to simulate phenomena with higher precision in space and time while at the same time applying state-of-the-art programming techniques and standards. This paper provides an overview of the status of the HCP and reports about first benchmark results for an HCP prototype which couples the fluid dynamics and time dependent neutronics code MGT-3D, the burn up code TNT and the fission product release code STACY. Due to the coupling of MGT-3D and TNT, a first step towards a new reactor operation and accident simulation code was made, where nuclide concentrations calculated by TNT lead to new cross sections, which are fed back into MGT-3D. Selected operation scenarios of the HTR-Module 200 concept plant and the HTTR were chosen to be simulated with the HCP prototype. The fission product release during normal operation conditions will be calculated with STACY based on a core status derived from SERPENT and MGT-3D. Comparisons will be shown against data generated by SERPENT and the legacy codes VSOP99/11, NAKURE and FRESCO-II.

  8. Present status of Indonesia HTR team activities

    Energy Technology Data Exchange (ETDEWEB)

    Lasman, As Natio; Arbie, Bakri [National Atomic Energy Agency BATAN, Jakarta (Indonesia)

    1998-09-01

    The Indonesian HTR Team was established in August 1993 to conduct studies on HTR technology and its application. The team is divided into 2 groups, i.e. reactor technology and safety group, which includes activities in the field of neutronics, thermohydraulics, fuel elements, information and communication, environmental, HTR material, techno-economical aspect, and application group. Especially in the field of application, the study is connected with CO2 conversion from the enriched CO2 of the Natuna gas field by using HTR. This activity is now influenced by another program for the Natuna gas field and the Memberamo river in Irian Jaya. Another activity concerns coal liquefaction because of the relative big abundance of coal resources in Indonesia. Coal are mostly utilized for electric power generation and for cement industries. Regarding the prediction that Indonesia is becoming one of the nett oil importing countries, the coal liquefaction is needed and will be realized if and only if the fluid fuel from coal is competitive. The study activity in desalination is still done by using an HTR or floating nuclear power plant, it is especially addressed for the eastern part of Indonesia. Particle coatings activity is still done in Yogyakarta Nuclear Research Center since 3 years ago, and it will be supported in the near future in the Center for Nuclear Fuel Element at Serpong. 3 refs.

  9. AP1000 core design with 50% MOX loading

    Energy Technology Data Exchange (ETDEWEB)

    Fetterman, Robert J. [Westinghouse Electric Company, LLC, Pittsburgh, PA (United States)], E-mail: fetterrj@westinghouse.com

    2009-04-15

    The European uility requirements (EUR) document states that the next generation European passive plant (EPP) reactor core design shall be optimized for UO{sub 2} fuel assemblies, with provisions made to allow for up to 50% mixed-oxide (MOX) fuel assemblies. The use of MOX in the core design will have significant impacts on key physics parameters and safety analysis assumptions. Furthermore, the MOX fuel rod design must also consider fuel performance criterion important to maintaining the integrity of the fuel rod over its intended lifetime. The purpose of this paper is to demonstrate that the AP1000 is capable of complying with the EUR requirement for MOX utilization without significant changes to the design of the plant. The analyses documented within will compare a 100% UO{sub 2} core design and a mixed MOX/UO{sub 2} core design, discussing relevant results related to reactivity management, power margin and fuel rod performance.

  10. Design, synthesis and applications of core-shell, hollow core, and nanorattle multifunctional nanostructures

    Science.gov (United States)

    El-Toni, Ahmed Mohamed; Habila, Mohamed A.; Labis, Joselito Puzon; Alothman, Zeid A.; Alhoshan, Mansour; Elzatahry, Ahmed A.; Zhang, Fan

    2016-01-01

    With the evolution of nanoscience and nanotechnology, studies have been focused on manipulating nanoparticle properties through the control of their size, composition, and morphology. As nanomaterial research has progressed, the foremost focus has gradually shifted from synthesis, morphology control, and characterization of properties to the investigation of function and the utility of integrating these materials and chemical sciences with the physical, biological, and medical fields, which therefore necessitates the development of novel materials that are capable of performing multiple tasks and functions. The construction of multifunctional nanomaterials that integrate two or more functions into a single geometry has been achieved through the surface-coating technique, which created a new class of substances designated as core-shell nanoparticles. Core-shell materials have growing and expanding applications due to the multifunctionality that is achieved through the formation of multiple shells as well as the manipulation of core/shell materials. Moreover, core removal from core-shell-based structures offers excellent opportunities to construct multifunctional hollow core architectures that possess huge storage capacities, low densities, and tunable optical properties. Furthermore, the fabrication of nanomaterials that have the combined properties of a core-shell structure with that of a hollow one has resulted in the creation of a new and important class of substances, known as the rattle core-shell nanoparticles, or nanorattles. The design strategies of these new multifunctional nanostructures (core-shell, hollow core, and nanorattle) are discussed in the first part of this review. In the second part, different synthesis and fabrication approaches for multifunctional core-shell, hollow core-shell and rattle core-shell architectures are highlighted. Finally, in the last part of the article, the versatile and diverse applications of these nanoarchitectures in

  11. CEA and AREVA HTR fuel particles manufacturing and characterization R and D Program

    Energy Technology Data Exchange (ETDEWEB)

    Charollais, F.; Perez, M.; Fonquernie, S.; Ablitzer, C.; Duhart, A.; Perrais, C.; Dugne, O.; Guillermier, P.; Harbonnier, G

    2004-07-01

    Worldwide, renewal of interest for High Temperature Reactors (HTR) moderated by graphite, using helium gas as coolant is due to the possibility offered by HTR technology to build small competitive modular units (100-300 MWe) and to produce high temperature gas required for hydrogen production or heat production. In this context, Commissariat a l'Energie Atomique (CEA) supported by AREVA, conducts R and D projects on HTR, which one is the mastering of the UO{sub 2} TRISO fuel fabrication technology including innovating prospects. The first step of the work is to recover fabrication know-how and to improve fabrication processes (for preparing the erection of a fuel pilot manufacture line of HTR particles). The second step will be the manufacturing of HTR fuel elements in purpose of irradiation tests. This publication deals with the know-how recovery and improved processes of UO{sub 2} TRISO manufacture, i.e. kernel and coatings manufacturing, the development of innovative characterization methods, a modelling approach of CVD processes and the status of the future laboratory manufacture line. Alternative fuel designs are also investigated, for instance the way of manufacturing UCO and UC{sub x} kernels with higher refractory coating material such as ZrC. (authors)

  12. Abrasion behavior of graphite pebble in lifting pipe of pebble-bed HTR

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Ke; Su, Jiageng [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Zhou, Hongbo [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Chinergy Co., LTD., Beijing 100193 (China); Peng, Wei; Liu, Bing [Institute of Nuclear and New Energy Technology, Advanced Nuclear Energy Technology Cooperation Innovation Center, The Key Laboratory of Advanced Nuclear Engineering and Safety, Ministry of Education, Beijing 10084 (China); Yu, Suyun, E-mail: suyuan@tsinghua.edu.cn [Center for Combustion Energy, The Key Laboratory for Thermal Science and Power Engineering, Ministry of Educations, Tsinghua University, Beijing 10084 (China)

    2015-11-15

    Highlights: • Quantitative determination of abrasion rate of graphite pebbles in different lifting velocities. • Abrasion behavior of graphite pebble in helium, air and nitrogen. • In helium, intensive collisions caused by oscillatory motion result in more graphite dust production. - Abstract: A pebble-bed high-temperature gas-cooled reactor (pebble-bed HTR) uses a helium coolant, graphite core structure, and spherical fuel elements. The pebble-bed design enables on-line refueling, avoiding refueling shutdowns. During circulation process, the pebbles are lifted pneumatically via a stainless steel lifting pipe and reinserted into the reactor. Inevitably, the movement of the fuel elements as they recirculate in the reactor produces graphite dust. Mechanical wear is the primary source of graphite dust production. Specifically, the sources are mechanisms of pebble–pebble contact, pebble–wall (structural graphite) contact, and fuel handling (pebble–metal abrasion). The key contribution to graphite dust production is from the fuel handling system, particularly from the lifting pipe. During pneumatic lift, graphite pebbles undergo multiple collisions with the stainless steel lifting pipe, thereby causing abrasion of the graphite pebbles and producing graphite dust. The present work explored the abrasion behavior of graphite pebble in the lifting pipe by measuring the abrasion rate at different lifting velocities. The abrasion rate of the graphite pebble in helium was found much higher than those in air and nitrogen. This gas environment effect could be explained by either tribology behavior or dynamic behavior. Friction testing excluded the possibility of tribology reason. The dynamic behavior of the graphite pebble was captured by analysis of the audio waveforms during pneumatic lift. The analysis results revealed unique dynamic behavior of the graphite pebble in helium. Oscillation and consequently intensive collisions occur during pneumatic lift, causing

  13. AP1000 core design with 50% MOX loading

    Energy Technology Data Exchange (ETDEWEB)

    Fetterman, Robert J. [Westinghouse Electric Company, LLC, Pittsburgh, PA (United States)

    2008-07-01

    The European Utility Requirements (EUR) document states that the next generation European Passive Plant (EPP) reactor core design shall be optimized for UO{sub 2} fuel assemblies, with provisions made to allow for up to 50% mixed-oxide (MOX) fuel assemblies. The use of MOX in the core design will have significant impacts on key physics parameters and safety analysis assumptions. Furthermore, the MOX fuel rod design must also consider fuel performance criterion important to maintaining the integrity of the fuel rod over its intended lifetime. The purpose of this paper is to demonstrate that the AP1000 is capable of complying with the EUR requirement for MOX utilization without significant changes to the design of the plant. The analyses documented within will compare a 100% UO{sub 2} core and a mixed MOX / UO{sub 2} core design, discussing relevant results related to reactivity management, power margin and fuel rod performance. (authors)

  14. Forming Core Elements for Strategic Design Management

    DEFF Research Database (Denmark)

    Beim, Anne; Vibæk, Kasper Sánchez

    2007-01-01

    . This evolution also leads to a demand for precise definitions of the values and qualities that can be used as managing tools in common building practice and it puts the traditional architectural design process under pressure. This paper outlines an approach to architectural quality as dealt with in the design...... process in an industrialized context. It also presents a way to analyse how and to what degree design processes are formed strategically according to specific architectural intentions (values). Through detailed interviews with professional architects, the way in which they manage the design process......, and to generate a common debate about quality in industrialized architecture. It is hoped that by presenting a way to talk about strategy and architectural value, it will inspire further elaboration of the field of strategic design management....

  15. Scalable Multi-core Architectures Design Methodologies and Tools

    CERN Document Server

    Jantsch, Axel

    2012-01-01

    As Moore’s law continues to unfold, two important trends have recently emerged. First, the growth of chip capacity is translated into a corresponding increase of number of cores. Second, the parallalization of the computation and 3D integration technologies lead to distributed memory architectures. This book provides a current snapshot of industrial and academic research, conducted as part of the European FP7 MOSART project, addressing urgent challenges in many-core architectures and application mapping.  It addresses the architectural design of many core chips, memory and data management, power management, design and programming methodologies. It also describes how new techniques have been applied in various industrial case studies. Describes trends towards distributed memory architectures and distributed power management; Integrates Network on Chip with distributed, shared memory architectures; Demonstrates novel design methodologies and frameworks for multi-core design space exploration; Shows how midll...

  16. Effects of geometry homogenization on the HTR-10 criticality calculations

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Meng-Jen [Center for Energy and Environmental Research, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC (China); Peir, Jinn-Jer, E-mail: jjpir@mx.thu.edu.tw [Nuclear Science and Technology Development Center, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC (China); Sheu, Rong-Jiun; Liang, Jenq-Horng [Institute of Nuclear Engineering and Science, National Tsing Hua University, No. 101, Section 2, Kuang-Fu Road, Hsinchu 30013, Taiwan, ROC (China)

    2014-05-01

    This study performs an investigation of geometry homogenization simulation using MCNP5 v1.51 and SCALE6 on the HTR-10 criticality calculations and focusing on the impact of geometry homogenization on k{sub eff} and neutron spectrum. The data libraries employed in this work are both continuous ENDF/B-VI respectively in MCNP5 and SCALE6. Six models, which are Model 1 – heterogeneous model, Model 2 – TRISO coating and graphite matrix homogenized model, Model 3 – TRISO homogenized model, Model 4 – fuel zone of fuel ball homogenized model, Model 5 – fuel ball homogenized model, and Model 6 – core homogenized model, are performed correspondingly by using MCNP5 and SCALE6 on the homogeneous effect analysis in HTR-10. The results revealed that the differences of k{sub eff} between MCNP5 and SCALE6 are all less than 300 pcm. The small differences of k{sub eff}, neutron spectra, and also the consistent discrepancies of neutron spectra between each homogenized model (Model 2–6) and Model 1 show the good agreement of MCNP5 with SCALE6 in the geometry homogenization.

  17. Research on Core Design for ACME Test Facility

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Fang Fang; Qin, Ben Ke [Tsinghua University, Beijing (China); Chang, Hua Jian; Chen, Lian [State Nuclear Power Technology R and D Center, Beijing (China)

    2011-08-15

    The Advanced Core-Cooling Mechanism Experiment (ACME) is designed and will be built to assess the performance of the passive safety system of CAP1400. In the reactor core of ACME, the electrical heater rods simulating the fuel rods provide the energy that drives the natural circulation in the primary loop, and single phase and two phase natural circulation are the main physical processes transporting core decay heat during small break loss of coolant accident (SBLOCA), which is the key part of the ACME test program. Natural circulation scaling which determines the integral scaling parameters of the test facility was presented in this paper, and the criteria in the core design were also investigated, which leads to a procedure that could be applied to the core design. According to the results from calculation, the maximum heat flux of heater rods, the maximum power for a single rod would increase while the number of rods would decrease with the increasing of pitch to diameter ratio (P/D) and the rod diameter fixed. Therefore a reasonable pitch value can be obtained by considering the maximum heat flux, the maximum single-rod power and other engineering factors. On this basis, the number of rods could be selected according to the similarity principle of flow area. Finally, a reasonable core arrangement could be designed by requiring the core to be symmetrical and approximately circular.

  18. One pass core design of a super fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Qingjie; Oka, Yoshiaki [Cooperative Major in Nuclear Energy, Waseda University, Tokyo 169-8555 (Japan)

    2013-07-01

    One pass core design for Supercritical-pressure light water-cooled fast reactor (Super FR) is proposed. The whole core is cooled with upward flow in one through flow pattern like PWR. Compared with the previous two pass core design; this new flow pattern can significantly simplify the core concept. Upper core structure, coolant flow scheme as well as refueling procedure are as simple as in PWR. In one pass core design, supercritical-pressure water is at approximately 25.0 MPa and enters the core at 280 C. degrees and is heated up in one through flow pattern upwardly to the average outlet temperature of 500 C. degrees. Great density change in vertical direction can cause significant axial power offset during the cycle. Meanwhile, Pu accumulated in the UO{sub 2} fuel blanket assemblies also introduces great power increase during cycle, which requires large amount of flow for heat removal and makes the outlet temperature of blanket low at the beginning of equilibrium cycle (BOEC). To deal with these issues, some MOX fuel is applied in the bottom region of the blanket assembly. This can help to mitigate the power change in blanket due to Pu accumulation and to increase the outlet temperature of the blanket during cycle. Neutron transport and thermohydraulics coupled calculation shows that this design can satisfy the requirement in the Super FR principle for both 500 C. degrees outlet temperature and negative coolant void reactivity. (authors)

  19. Conceptual study of advanced PWR core design. Development of advanced PWR core neutronics analysis system

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hyo; Kim, Seung Cho; Kim, Taek Kyum; Cho, Jin Young; Lee, Hyun Cheol; Lee, Jung Hun; Jung, Gu Young [Seoul National University, Seoul (Korea, Republic of)

    1995-08-01

    The neutronics design system of the advanced PWR consists of (i) hexagonal cell and fuel assembly code for generation of homogenized few-group cross sections and (ii) global core neutronics analysis code for computations of steady-state pin-wise or assembly-wise core power distribution, core reactivity with fuel burnup, control rod worth and reactivity coefficients, transient core power, etc.. The major research target of the first year is to establish the numerical method and solution of multi-group diffusion equations for neutronics code development. Specifically, the following studies are planned; (i) Formulation of various numerical methods such as finite element method(FEM), analytical nodal method(ANM), analytic function expansion nodal(AFEN) method, polynomial expansion nodal(PEN) method that can be applicable for the hexagonal core geometry. (ii) Comparative evaluation of the numerical effectiveness of these methods based on numerical solutions to various hexagonal core neutronics benchmark problems. Results are follows: (i) Formulation of numerical solutions to multi-group diffusion equations based on numerical methods. (ii) Numerical computations by above methods for the hexagonal neutronics benchmark problems such as -VVER-1000 Problem Without Reflector -VVER-440 Problem I With Reflector -Modified IAEA PWR Problem Without Reflector -Modified IAEA PWR Problem With Reflector -ANL Large Heavy Water Reactor Problem -Small HTGR Problem -VVER-440 Problem II With Reactor (iii) Comparative evaluation on the numerical effectiveness of various numerical methods. (iv) Development of HEXFEM code, a multi-dimensional hexagonal core neutronics analysis code based on FEM. In the target year of this research, the spatial neutronics analysis code for hexagonal core geometry(called NEMSNAP-H temporarily) will be completed. Combination of NEMSNAP-H with hexagonal cell and assembly code will then equip us with hexagonal core neutronics design system. (Abstract Truncated)

  20. PRELIMINARY RESULTS OF THE AGC-4 IRRADIATION IN THE ADVANCED TEST REACTOR AND DESIGN OF AGC-5 (HTR16-18469)

    Energy Technology Data Exchange (ETDEWEB)

    Davenport, Michael; Petti, D. A.

    2016-11-01

    The United States Department of Energy’s Advanced Reactor Technologies (ART) Program will irradiate up to six nuclear graphite creep experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The graphite experiments are being irradiated over an approximate eight year period to support development of a graphite irradiation performance data base on the new nuclear grade graphites now available for use in high temperature gas reactors. The goals of the irradiation experiments are to obtain irradiation performance data, including irradiation creep, at different temperatures and loading conditions to support design of the Very High Temperature Gas Reactor (VHTR), as well as other future gas reactors. The experiments each consist of a single capsule that contain six stacks of graphite specimens, with half of the graphite specimens in each stack under a compressive load, while the other half of the specimens are not be subjected to a compressive load during irradiation. The six stacks have differing compressive loads applied to the top half of diametrically opposite pairs of specimen stacks. A seventh specimen stack in the center of the capsule does not have a compressive load. The specimens are being irradiated in an inert sweep gas atmosphere with on-line temperature and compressive load monitoring and control. There are also samples taken of the sweep gas effluent to measure any oxidation or off-gassing of the specimens that may occur during initial start-up of the experiment. The first experiment, AGC-1, started its irradiation in September 2009, and the irradiation was completed in January 2011. The second experiment, AGC-2, started its irradiation in April 2011 and completed its irradiation in May 2012. The third experiment, AGC-3, started its irradiation in late November 2012 and completed in the April of 2014. AGC-4 is currently being irradiated in the ATR. This paper will briefly discuss the preliminary irradiation results

  1. Feasibility Study of Core Design with a Monte Carlo Code for APR1400 Initial core

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jinsun; Chang, Do Ik; Seong, Kibong [KEPCO NF, Daejeon (Korea, Republic of)

    2014-10-15

    The Monte Carlo calculation becomes more popular and useful nowadays due to the rapid progress in computing power and parallel calculation techniques. There have been many attempts to analyze a commercial core by Monte Carlo transport code using the enhanced computer capability, recently. In this paper, Monte Carlo calculation of APR1400 initial core has been performed and the results are compared with the calculation results of conventional deterministic code to find out the feasibility of core design using Monte Carlo code. SERPENT, a 3D continuous-energy Monte Carlo reactor physics burnup calculation code is used for this purpose and the KARMA-ASTRA code system, which is used for a deterministic code of comparison. The preliminary investigation for the feasibility of commercial core design with Monte Carlo code was performed in this study. Simplified core geometry modeling was performed for the reactor core surroundings and reactor coolant model is based on two region model. The reactivity difference at HZP ARO condition between Monte Carlo code and the deterministic code is consistent with each other and the reactivity difference during the depletion could be reduced by adopting the realistic moderator temperature. The reactivity difference calculated at HFP, BOC, ARO equilibrium condition was 180 ±9 pcm, with axial moderator temperature of a deterministic code. The computing time will be a significant burden at this time for the application of Monte Carlo code to the commercial core design even with the application of parallel computing because numerous core simulations are required for actual loading pattern search. One of the remedy will be a combination of Monte Carlo code and the deterministic code to generate the physics data. The comparison of physics parameters with sophisticated moderator temperature modeling and depletion will be performed for a further study.

  2. APR1000 Core Design with 30% MOX Fuel Loading

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hwan Soo; Choi, Yu Sun; Bae, Seong Man; Yoo, Keun Bae [KEPCO Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The Korea Electric Power Corporation (KEPCO) has developed the APR1000 standard design, which uses a two-loop 1000 MWe pressurized water reactor (PWR). The APR1000 incorporates a variety of ADFs(advanced design features) from the based model of the Shin Kori Units 1 and 2(OPR1000). One of ADFs, the 30% core loading of MOX (Mixed Oxide, PuO{sub 2}-UO{sub 2}) fuel, is a major characteristic of APR1000. In this paper, APR1000 core design with 30% MOX fuel loading is performed and safety and key physics parameters are analyzed with those of 100% UO{sub 2} loaded core to verify the feasibility

  3. Design of dual-core optical fibers with NEMS functionality.

    Science.gov (United States)

    Podoliak, Nina; Lian, Zhenggang; Loh, Wei H; Horak, Peter

    2014-01-13

    An optical fiber with nano-electromechanical functionality is presented. The fiber exhibits a suspended dual-core structure that allows for control of the optical properties via nanometer-range mechanical movements. We investigate electrostatic actuation achieved by applying a voltage to specially designed electrodes integrated in the cladding. Numerical and analytical calculations are preformed to optimize the fiber and electrode design. Based on this geometry an all-fiber optical switch is investigated; we find that optical switching of light between the two cores can be achieved in a 10 cm fiber with an operating voltage of 35 V.

  4. Research on the Computed Tomography Pebble Flow Detecting System for HTR-PM

    Directory of Open Access Journals (Sweden)

    Xin Wan

    2017-01-01

    Full Text Available Pebble dynamics is important for the safe operation of pebble-bed high temperature gas-cooled reactors and is a complicated problem of great concern. To investigate it more authentically, a computed tomography pebble flow detecting (CT-PFD system has been constructed, in which a three-dimensional model is simulated according to the ratio of 1 : 5 with the core of HTR-PM. A multislice helical CT is utilized to acquire the reconstructed cross-sectional images of simulated pebbles, among which special tracer pebbles are designed to indicate pebble flow. Tracer pebbles can be recognized from many other background pebbles because of their heavy kernels that can be resolved in CT images. The detecting principle and design parameters of the system were demonstrated by a verification experiment on an existing CT system in this paper. Algorithms to automatically locate the three-dimensional coordinates of tracer pebbles and to rebuild the trajectory of each tracer pebble were presented and verified. The proposed pebble-detecting and tracking technique described in this paper will be implemented in the near future.

  5. Thermal Hydraulic Analysis Using GIS on Application of HTR to Thermal Recovery of Heavy Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Yangping Zhou

    2012-01-01

    Full Text Available At present, large water demand and carbon dioxide (CO2 emissions have emerged as challenges of steam injection for oil thermal recovery. This paper proposed a strategy of superheated steam injection by the high-temperature gas-cooled reactor (HTR for thermal recovery of heavy oil, which has less demand of water and emission of CO2. The paper outlines the problems of conventional steam injection and addresses the advantages of superheated steam injection by HTR from the aspects of technology, economy, and environment. A Geographic Information System (GIS embedded with a thermal hydraulic analysis function is designed and developed to analyze the strategy, which can make the analysis work more practical and credible. Thermal hydraulic analysis using this GIS is carried out by applying this strategy to a reference heavy oil field. Two kinds of injection are considered and compared: wet steam injection by conventional boilers and superheated steam injection by HTR. The heat loss, pressure drop, and possible phase transformation are calculated and analyzed when the steam flows through the pipeline and well tube and is finally injected into the oil reservoir. The result shows that the superheated steam injection from HTR is applicable and promising for thermal recovery of heavy oil reservoirs.

  6. Design of the HPLWR reactor core; Auslegung des HPLWR Reaktorkerns

    Energy Technology Data Exchange (ETDEWEB)

    Schulenberg, T. [Karlsruher Institut fuer Technologie, Karlsruhe (Germany). IKET; Maraczy, C. [KFKI Atomenergia Kutatointezet (AEKI), Budapest (Hungary); Heinecke, J. [AREVA NP GmbH, Erlangen (Germany); Bernnat, W. [Stuttgart Univ. (Germany). IKE

    2010-05-15

    The high performance light water reactor (HPLWR) is a LWR working with supercritical water as coolant medium and moderator. The operational pressure is 25 MPa and the fresh steam temperatures are above 500 C. In order to restrict the peak temperature in the reactor core to less than 630 C (upper limit of the corrosion resistance of stainless steel fuel cans) a three-step heating of the reactor core was proposed. The authors discuss the results of thermal hydraulic and neutronic calculations performed during the last three years. The coolant mixing is the key process of the concept. The design of the fuel and water cans is using double-walled constructions with ceramic insulations to avoid inadmissible heating o the moderator medium. Stress and deformation analysis of the core structures were performed. The calculated results still need experimental validation.

  7. Designing an Institutional Web-based Core Facility Management System

    Science.gov (United States)

    Tabarini, D.; Clisham, S.; John, D.; Hagen, A.

    2011-01-01

    The authors and their four institutions collaborated to (i) identify the key challenges to core facility management; (ii) identify the requirements for an effective core facility management system; (iii) design, test and deploy such a system. Through a series of interviews with all participants in the core work flow (customers, core staff, administrators), the team identified a number of key challenges, including: (i) difficulty for researchers in identifying available services; (ii) inconsistent processes for requesting services; (iii) inadequate controls for approving service requests; (iv) inefficient processes for tracking and communicating about project processes; (v) time-consuming billing practices; (vi) incomplete revenue capture; (vii) manual reporting processes. The team identified the following requirements for a system to address these challenges: (i) ability to support a broad range of core business practices such as complex quote generation and project management; calendaring/equipment reservation management; sample tracking; complex forms; and import of usage data from hardware; (ii) ability to offer services for both internal and external customers, including flexible pricing and off-site access; (iii) ability to interact with institutional financial systems (e.g. SAP, PeopleSoft, Lawson, SunGard Banner) and identify management systems (e.g. Microsoft Active Directory, LDAP, and other SAML 2.0-compliant services). The team developed and deployed this system across the collaborative partners, as well as other major research institutions.

  8. Designing the colorectal cancer core dataset in Iran

    Directory of Open Access Journals (Sweden)

    Sara Dorri

    2017-01-01

    Full Text Available Background: There is no need to explain the importance of collection, recording and analyzing the information of disease in any health organization. In this regard, systematic design of standard data sets can be helpful to record uniform and consistent information. It can create interoperability between health care systems. The main purpose of this study was design the core dataset to record colorectal cancer information in Iran. Methods: For the design of the colorectal cancer core data set, a combination of literature review and expert consensus were used. In the first phase, the draft of the data set was designed based on colorectal cancer literature review and comparative studies. Then, in the second phase, this data set was evaluated by experts from different discipline such as medical informatics, oncology and surgery. Their comments and opinion were taken. In the third phase refined data set, was evaluated again by experts and eventually data set was proposed. Results: In first phase, based on the literature review, a draft set of 85 data elements was designed. In the second phase this data set was evaluated by experts and supplementary information was offered by professionals in subgroups especially in treatment part. In this phase the number of elements totally were arrived to 93 numbers. In the third phase, evaluation was conducted by experts and finally this dataset was designed in five main parts including: demographic information, diagnostic information, treatment information, clinical status assessment information, and clinical trial information. Conclusion: In this study the comprehensive core data set of colorectal cancer was designed. This dataset in the field of collecting colorectal cancer information can be useful through facilitating exchange of health information. Designing such data set for similar disease can help providers to collect standard data from patients and can accelerate retrieval from storage systems.

  9. Pre-service tightness tests of HTR-10 primary loop pressure boundary system

    Energy Technology Data Exchange (ETDEWEB)

    Liu Junjie; He Shuyan; Yu Suyuan. E-mail: suyuan@inet.tsinghua.edu.cn; Zhang Zhengming

    2003-06-01

    The main design and operating parameters for the 10 MW high temperature gas-cooled reactor (HTR-10) primary loop pressure boundary system are introduced in this paper. The component installations and the pneumatic and tightness test are also described, including the objectives and methods. The leakage rate test results are analyzed to show that the results meet the design requirements and have enough safety redundancy.

  10. HPLWR equilibrium core design with the KARATE code system

    Energy Technology Data Exchange (ETDEWEB)

    Maraczy, Cs.; Hegyi, Gy.; Hordosy, G.; Temesvari, E. [KFKI Atomic Energy Research Inst., Hungarian Academy of Sciences, Budapest (Hungary)

    2011-07-01

    The High Performance Light Water Reactor (HPLWR) is the European version of the various supercritical water cooled reactor proposals. The paper presents the activity of KFKI-AEKI in the field of neutronic core design within the framework of the 'HPLWR Phase 2' FP-6 and the Hungarian 'NUKENERG' projects. As the coolant density along the axial direction shows remarkable change, coupled neutronic- thermohydraulic calculations are essential which take into account the heating of moderator in the special water rods of the assemblies. A parametrized diffusion cross section library was prepared for the HPLWR assembly with the MULTICELL neutronic transport code. The parametrized cross sections are used by the KARATE program system, which was verified for supercritical conditions by comparative Monte Carlo calculations. To design the HPLWR equilibrium core preliminary loadings were assessed, which contain insulated assemblies with Gd burnable absorbers. The fuel assemblies have radial and axial enrichment zoning to reduce hot spots. (author)

  11. The HtrA2 Drosophila model of Parkinson's disease is suppressed by the pro-survival Bcl-2 Buffy.

    Science.gov (United States)

    M'Angale, P Githure; Staveley, Brian E

    2017-01-01

    Mutations in High temperature requirement A2 (HtrA2), also designated PARK13, which lead to the loss of its protease activity, have been associated with Parkinson's disease (PD). HtrA2 is a mitochondrial protease that translocates to the cytosol upon the initiation of apoptosis where it participates in the abrogation of inhibitors of apoptosis (IAP) inhibition of caspases. Here, we demonstrate that the loss of the HtrA2 function in the dopaminergic neurons of Drosophila melanogaster results in PD-like phenotypes, and we attempt to restore the age-dependent loss in locomotor ability by co-expressing the sole pro-survival Bcl-2 homologue Buffy. The inhibition of HtrA2 in the dopaminergic neurons of Drosophila resulted in shortened lifespan and impaired climbing ability, and the overexpression of Buffy rescued the reduction in lifespan and the age-dependent loss of locomotor ability. In supportive experiments, the inhibition of HtrA2 in the Drosophila eye results in eye defects, marked by reduction in ommatidia number and increased disruption of the ommatidial array; phenotypes that are suppressed by the overexpression of Buffy.

  12. System design description for GCFR-core flow test loop

    Energy Technology Data Exchange (ETDEWEB)

    Huntley, W.R.; Grindell, A.G.

    1980-12-01

    The Core Flow Test Loop is a high-pressure, high-temperature, out-of-reactor helium circulation system that is being constructed to permit detailed study of the thermomechanical and thermal performance at prototypic steady-state and transient operating conditions of simulated segments of core assemblies for a GCFR Demonstration Plant, as designed by General Atomic Company. It will also permit the expermental verification of predictive analytical models of the GCFR core assemblies needed to reduce operational and safety uncertainties of the GCFR. Full-sized blanket assemblies and segments of fuel rod and control rod fuel assemblies will be simulated with test bundles of electrically powered fuel rod or blanket rod simulators. The loop will provide the steady-state and margin test requirements of bundle power and heat removal, and of helium coolant flow rate, pressure, and temperature for test bundles having up to 91 rods; these requirements set the maximum power, coolant helium flow, and thermal requirements for the loop. However, the size of the test vessel that contains the test bundles will be determined by the bundles that simulate a full-sized GCFR blanket assembly. The loop will also provide for power and coolant transients to simulate transient operation of GCFR core assemblies, including the capability for rapid helium depressurization to simulate the depressurization class of GCFR accidents. In addition, the loop can be used as an out-of-reactor test bed for characterizing in-reactor test bundle configurations.

  13. Nuclear design and analysis report for KALIMER breakeven core conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Ji; Song, Hoon; Lee, Ki Bog; Chang, Jin Wook; Hong, Ser Gi; Kim, Young Gyun; Kim, Yeong Il

    2002-04-15

    During the phase 2 of LMR design technology development project, the breakeven core configuration was developed with the aim of the KALIMER self-sustaining with regard to the fissile material. The excess fissile material production is limited only to the extent of its own requirement for sustaining its planned power operation. The average breeding ratio is estimated to be 1.05 for the equilibrium core and the fissile plutonium gain per cycle is 13.9 kg. The nuclear performance characteristics as well as the reactivity coefficients have been analyzed so that the design evaluation in other activity areas can be made. In order to find out a realistic heavy metal flow evolution and investigate cycle-dependent nuclear performance parameter behaviors, the startup and transition cycle loading strategies are developed, followed by the startup core physics analysis. Driver fuel and blankets are assumed to be shuffled at the time of each reload. The startup core physics analysis has shown that the burnup reactivity swing, effective delayed neutron fraction, conversion ratio and peak linear heat generation rate at the startup core lead to an extreme of bounding physics data for safety analysis. As an outcome of this study, a whole spectrum of reactor life is first analyzed in detail for the KALIMER core. It is experienced that the startup core analysis deserves more attention than the current design practice, before the core configuration is finalized based on the equilibrium cycle analysis alone.

  14. Core design analysis of the supercritical water fast reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mori, M.

    2005-10-01

    Light Water Reactor technology is nowadays the most successful commercial application of fission reactors for the production of electricity. However, in the next years, nuclear industry will have to face new and demanding challenges. The need for sustainable and cheap sources of energy, the need for public acceptance, the need for even higher safety standards, the need to minimize waste production are only a few examples. It is for these very reasons that a few next generation nuclear reactor concepts were selected for extensive research and development. Super critical water cooled reactors are one of them. The use of a supercritical coolant would in fact allow for higher thermal efficiencies and a more compact plant design. As a matter of fact, steam generators, or steam separators and driers would not be needed thus, significantly reducing construction costs. Moreover, because of the high heat capacity of supercritical water, comparatively less coolant would be needed to refrigerate the reactor. Consequently, a water-cooled reactor with a fast neutron spectrum could potentially be designed: the SuperCritical water Fast Reactor. This system presents unique features combining well-known fast and light water reactor characteristics in one design (e.g. the tendency to a positive void reactivity coefficient together with Loss Of Coolant Accidents, as design basis). The core is in fact loaded with highly enriched Mixed Oxide fuel (average plutonium content of {approx}23%), and presents a peculiar and significant geometrical and material heterogeneity (use of radial and axial blankets, solid moderator layers, several enrichment zones). The safety analysis of this very complex core layout, the development of suitable tools of investigation, and the optimization of the void reactivity effect through core design, is the main objective of this work. (orig.)

  15. Modelling of HTR (High Temperature Reactor Pebble-Bed 10 MW to Determine Criticality as A Variations of Enrichment and Radius of the Fuel (Kernel With the Monte Carlo Code MCNP4C

    Directory of Open Access Journals (Sweden)

    Hammam Oktajianto

    2014-12-01

    Full Text Available Gas-cooled nuclear reactor is a Generation IV reactor which has been receiving significant attention due to many desired characteristics such as inherent safety, modularity, relatively low cost, short construction period, and easy financing. High temperature reactor (HTR pebble-bed as one of type of gas-cooled reactor concept is getting attention. In HTR pebble-bed design, radius and enrichment of the fuel kernel are the key parameter that can be chosen freely to determine the desired value of criticality. This paper models HTR pebble-bed 10 MW and determines an effective of enrichment and radius of the fuel (Kernel to get criticality value of reactor. The TRISO particle coated fuel particle which was modelled explicitly and distributed in the fuelled region of the fuel pebbles using a Simple-Cubic (SC lattice. The pebble-bed balls and moderator balls distributed in the core zone using a Body-Centred Cubic lattice with assumption of a fresh fuel by the fuel enrichment was 7-17% at 1% range and the size of the fuel radius was 175-300 µm at 25 µm ranges. The geometrical model of the full reactor is obtained by using lattice and universe facilities provided by MCNP4C. The details of model are discussed with necessary simplifications. Criticality calculations were conducted by Monte Carlo transport code MCNP4C and continuous energy nuclear data library ENDF/B-VI. From calculation results can be concluded that an effective of enrichment and radius of fuel (Kernel to achieve a critical condition was the enrichment of 15-17% at a radius of 200 µm, the enrichment of 13-17% at a radius of 225 µm, the enrichments of 12-15% at radius of 250 µm, the enrichments of 11-14% at a radius of 275 µm and the enrichment of 10-13% at a radius of 300 µm, so that the effective of enrichments and radii of fuel (Kernel can be considered in the HTR 10 MW. Keywords—MCNP4C, HTR, enrichment, radius, criticality 

  16. Analysis of three-phase power transformer laminated magnetic core designs

    Directory of Open Access Journals (Sweden)

    M.I. Levin

    2014-03-01

    Full Text Available Analysis and research into properties and parameters of different-type laminated magnetic cores of three-phase power transformers are conducted. Most of new laminated magnetic core designs are found to have significant shortcomings resulted from design and technological features of their manufacturing. These shortcomings cause increase in ohmic loss in the magnetic core, which eliminates advantages of the new core configurations and makes them uncompetitive as compared with the classical laminated magnetic core design.

  17. Developing engineering design core competences through analysis of industrial products

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp; Lenau, Torben Anker

    2011-01-01

    Most product development work carried out in industrial practice is characterised by being incremental, i.e. the industrial company has had a product in production and on the market for some time, and now time has come to design a new and upgraded variant. This type of redesign project requires...... that the engineering designers have core design competences to carry through an analysis of the existing product encompassing both a user-oriented side and a technical side, as well as to synthesise solution proposals for the new and upgraded product. The authors of this paper see an educational challenge in staging...... a course module, in which students develop knowledge, understanding and skills, which will prepare them for being able to participate in and contribute to redesign projects in industrial practice. In the course module Product Analysis and Redesign that has run for 8 years we have developed and refined...

  18. Space Launch System, Core Stage, Structural Test Design and Implementation

    Science.gov (United States)

    Shaughnessy, Ray

    2017-01-01

    As part of the National Aeronautics and Space Administration's (NASA) Space Launch System (SLS) Program, engineers at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Alabama are working to design, develop and implement the SLS Core Stage structural testing. The SLS will have the capability to return humans to the Moon and beyond and its first launch is scheduled for December of 2017. The SLS Core Stage consist of five major elements; Forward Skirt, Liquid Oxygen (LOX) tank, Intertank (IT), Liquid Hydrogen (LH2) tank and the Engine Section (ES). Structural Test Articles (STA) for each of these elements are being designed and produced by Boeing at Michoud Assembly Facility located in New Orleans, La. The structural test for the Core Stage STAs (LH2, LOX, IT and ES) are to be conducted by the MSFC Test Laboratory. Additionally, the MSFC Test Laboratory manages the Structural Test Equipment (STE) design and development to support the STAs. It was decided early (April 2012) in the project life that the LH2 and LOX tank STAs would require new test stands and the Engine Section and Intertank would be tested in existing facilities. This decision impacted schedules immediately because the new facilities would require Construction of Facilities (C of F) funds that require congressional approval and long lead times. The Engine Section and Intertank structural test are to be conducted in existing facilities which will limit lead times required to support the first launch of SLS. With a SLS launch date of December, 2017 Boeing had a need date for testing to be complete by September of 2017 to support flight certification requirements. The test facilities were required to be ready by October of 2016 to support test article delivery. The race was on to get the stands ready before Test Article delivery and meet the test complete date of September 2017. This paper documents the past and current design and development phases and the supporting processes, tools, and

  19. The Use of Th in HTR: State of the Art and Implementation in Th/Pu Fuel Cycles

    Directory of Open Access Journals (Sweden)

    Guido Mazzini

    2009-01-01

    Full Text Available Nowadays nuclear is the only greenhouse-free source that can appreciably respond to the increasing worldwide energy demand. The use of Thorium in the nuclear energy production may offer some advantages to accomplish this task. Extensive R&D on the thorium fuel cycle has been conducted in many countries around the world. Starting from the current nuclear waste policy, the EU-PUMA project focuses on the potential benefits of using the HTR core as a Pu/MA transmuter. In this paper the following aspects have been analysed: (1 the state-of-the-art of the studies on the use of Th in different reactors, (2 the use of Th in HTRs, with a particular emphasis on Th-Pu fuel cycles, (3 an original assessment of Th-Pu fuel cycles in HTR. Some aspects related to Thorium exploitation were outlined, particularly its suitability for working in pebble-bed HTR in a Th-Pu fuel cycle. The influence of the Th/Pu weight fraction at BOC in a typical HTR pebble was analysed as far as the reactivity trend versus burn-up, the energy produced per Pu mass, and the Pu isotopic composition at EOC are concerned. Although deeper investigations need to be performed in order to draw final conclusions, it is possible to state that some optimized Th percentage in the initial Pu/Th fuel could be suggested on the basis of the aim we are trying to reach.

  20. A 100% MOX core design using a highly moderated concept

    Energy Technology Data Exchange (ETDEWEB)

    Girieud, R.; Guigon, B. [CEA/Cadarache, 13 Saint-Paul-lez-Durance (France); Lenain, R.; Barbet, N.; Royer, E.

    1997-12-31

    In the framework of plutonium utilization in future French nuclear plants, feasibility studies were done on large Pressurized Water Reactor (PWR) cores, with 100% MOX (Mixed OXide) fuel assemblies reloads aiming at a large consumption of plutonium. Increasing the moderation ratio was adopted as an approach to make the reactivity control of 100% MOX realistically achievable. This paper presents the results of core design studies, operating transient analyses, fuel management strategies and isotopic balance studies recently performed at CEA/DRN in the framework of innovative systems. Three strategies of fuel management (at equilibrium) were studied: 4 x 12 months (with low leakage loading pattern), 3 x 18 months (reference) and 2 x 24 months (with and without burnable absorbers in fuel). With a moderation ratio of 4 (19 x 19 square lattice), an initial content of plutonium in fuel from 7.5% to 10.3% is needed. In these conditions, the feasibility of 100% MOX PWR is established in standard operation conditions. The presented design allows the unitary power to be maintained. (author)

  1. Regulatory Audit Activities on Nuclear Design of Reactor Cores

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Chae-Yong; Lee, Gil Soo; Lee, Jaejun; Kim, Gwan-Young; Bae, Moo-Hun [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    Regulatory audit analyses are initiated on the purpose of deep knowledge, solving safety issues, being applied in the review of licensee's results. The current most important safety issue on nuclear design is to verify bias and uncertainty on reactor physics codes to examine the behaviors of high burnup fuel during rod ejection accident (REA) and LOCA, and now regulatory audits are concentrated on solving this issue. KINS develops regulatory audit tools on its own, and accepts ones verified from foreign countries. The independent audit tools are sometimes standardized through participating the international programs. New safety issues on nuclear design, reactor physics tests, advanced reactor core design are steadily raised, which are mainly drawn from the independent examination tools. It is some facing subjects for the regulators to find out the unidentified uncertainties in high burnup fuels and to systematically solve them. The safety margin on nuclear design might be clarified by precisely having independent tools and doing audit calculations by using them. SCALE-PARCS/COREDAX and the coupling with T-H code or fuel performance code would be certainly necessary for achieving these purposes.

  2. Exploring Many-Core Design Templates for FPGAs and ASICs

    Directory of Open Access Journals (Sweden)

    Ilia Lebedev

    2012-01-01

    Full Text Available We present a highly productive approach to hardware design based on a many-core microarchitectural template used to implement compute-bound applications expressed in a high-level data-parallel language such as OpenCL. The template is customized on a per-application basis via a range of high-level parameters such as the interconnect topology or processing element architecture. The key benefits of this approach are that it (i allows programmers to express parallelism through an API defined in a high-level programming language, (ii supports coarse-grained multithreading and fine-grained threading while permitting bit-level resource control, and (iii reduces the effort required to repurpose the system for different algorithms or different applications. We compare template-driven design to both full-custom and programmable approaches by studying implementations of a compute-bound data-parallel Bayesian graph inference algorithm across several candidate platforms. Specifically, we examine a range of template-based implementations on both FPGA and ASIC platforms and compare each against full custom designs. Throughout this study, we use a general-purpose graphics processing unit (GPGPU implementation as a performance and area baseline. We show that our approach, similar in productivity to programmable approaches such as GPGPU applications, yields implementations with performance approaching that of full-custom designs on both FPGA and ASIC platforms.

  3. Ideas to Design an in situ Diamond Drilling Core Splitter within Soft ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... challenges in core splitting are imperfect division, time consuming, labour intensive and dust generation. This paper studied the wireline system of core barrel assembly and the device used in splitting of core (core splitting machine) at the surface, to provide ideas which would help design a mechanism that ...

  4. Effects of lumbar artificial disc design on intervertebral mobility: in vivo comparison between mobile-core and fixed-core.

    Science.gov (United States)

    Delécrin, Joël; Allain, Jérôme; Beaurain, Jacques; Steib, Jean-Paul; Huppert, Jean; Chataigner, Hervé; Ameil, Marc; Aubourg, Lucie; Nguyen, Jean-Michel

    2012-06-01

    Although in theory, the differences in design between fixed-core and mobile-core prostheses should influence motion restoration, in vivo kinematic differences linked with prosthesis design remained unclear. The aim of this study was to investigate the rationale that the mobile-core design seems more likely to restore physiological motion since the translation of the core could help to mimic the kinematic effects of the natural nucleus. In vivo intervertebral motion characteristics of levels implanted with the mobile-core prosthesis were compared with untreated levels of the same population, levels treated by a fixed-core prosthesis, and normal levels (data from literature). Patients had a single-level implantation at L4L5 or L5S1 including 72 levels with a mobile-core prosthesis and 33 levels with a fixed-core prosthesis. Intervertebral mobility characteristics included the range of motion (ROM), the motion distribution between flexion and extension, the prosthesis core translation (CT), and the intervertebral translation (VT). A method adapted to the implanted segments was developed to measure the VT: metal landmarks were used instead of the bony landmarks. The reliability assessment of the VT measurement method showed no difference between three observers (p core prosthesis replicated physiological VT at L4L5 levels but not at L5S1 levels, and that the fixed-core prosthesis did not replicate physiological VT at any level by increasing VT. As the VT decreased when the CT increased (p core mobility minimized the VT. Furthermore, some physiologic mechanical behaviors seemed to be maintained: the VT was higher at implanted the L4L5 level than at the implanted L5S1 level, and the CT appeared lower at the L4L5 level than at the L5S1 level. ROM and motion distribution were not different between the mobile-core prosthesis and the fixed-core prosthesis implanted levels. This study validated in vivo the concept that a mobile-core helps to restore some physiological

  5. Design Core Commonalities: A Study of the College of Design at Iowa State University

    Science.gov (United States)

    Venes, Jane

    2015-01-01

    This comprehensive study asks what a group of rather diverse disciplines have in common. It involves a cross-disciplinary examination of an entire college, the College of Design at Iowa State University. This research was intended to provide a sense of direction in developing and assessing possible core content. The reasoning was that material…

  6. Potential applications of a small HTR-GT

    Energy Technology Data Exchange (ETDEWEB)

    Crommelin, G.A.K. [Romawa, Voorschoten (Netherlands)

    1998-09-01

    In the first half of this year the INCOGEN pre-feasibility study has been finished. In view of the title of this meeting this paper deals with some aspects concerning the non-technical side of this study: the potential applications and the possibilities to open up markets, in other words how to achieve the most promising future for nuclear energy generation for the small power range. To open up any market one must accept that there is a strong relation between the price based upon through life costing and social acceptance, in other words a requirement of safety, good performance, reliability, an easily understandable reactor design, energy conversion unit and controls. The approach to this relationship will be from the potential user`s point of view and will use several well-proven thoughts and tools from the gas turbine and warship design branches. For the HTR-GT to be used in the small power range, competitive costs seems to be the biggest challenge and should get a maximum of attention. 8 refs.

  7. Design and Testing of Sandwich Structures with Different Core Materials

    Directory of Open Access Journals (Sweden)

    Henrik HERRANEN

    2012-03-01

    Full Text Available The purpose of this study was to design a light-weight sandwich panel for trailers. Strength calculations and selection of different materials were carried out in order to find a new solution for this specific application. The sandwich materials were fabricated using vacuum infusion technology. The different types of sandwich composite panels were tested in 4-point bending conditions according to ASTM C393/C393M. Virtual testing was performed by use of ANSYS software to simplify the core material selection process and to design the layers. 2D Finite element analysis (FEA of 4-point bending was made with ANSYS APDL (Classic software. Data for the FEA was obtained from the tensile tests of glass fiber plastic (GFRP laminates. Virtual 2D results were compared with real 4-point bending tests.  3D FEA was applied to virtually test the selected sandwich structure in real working conditions. Based on FEA results the Pareto optimality concept has been applied and optimal solutions determined.DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1340

  8. 5-HTR1A and 5-HTR2A genetic polymorphisms and SSRI antidepressant response in depressive Chinese patients

    Directory of Open Access Journals (Sweden)

    Dong ZQ

    2016-07-01

    Full Text Available Zai-Quan Dong,1,* Xi-Rong Li,2,* Lin He,3,4 Guang He,3,4 Tao Yu,3,4 Xue-Li Sun1 1Psychological Center, West China Hospital, Sichuan University, Chengdu, Sichuan, 2Mental Health Center, First Affiliated Hospital, Chongqing Medical University, Chongqing, 3Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders (Ministry of Education, Shanghai Jiao Tong University, 4Shanghai Key Laboratory of Psychotic Disorders, Shanghai Mental Health Center, Shanghai Jiao Tong University School of Medicine, Shanghai, People’s Republic of China *These authors contributed equally to this work Objective: Genetic variabilities within the serotoninergic system may predict response or remission to antidepressant drugs. Several serotonin receptor (5-HTR gene polymorphisms have been associated with susceptibility to psychiatric diseases. In this study, we analyzed the correlation between 5-HTR1A and 5-HTR2A polymorphisms and response or remission to selective serotonin reuptake inhibitors (SSRIs drugs. Methods: Two hundred and ninety patients who met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for major depressive disorder were involved in this study. SSRIs (fluoxetine, paroxetine, citalopram, or sertraline were selected randomly for treatment. The Hamilton Rating Scale for Depression was used to evaluate the antidepressant effect. To assess 5-HTR gene variabilities, two single-nucleotide polymorphisms in 5-HTR1A (rs1364043 and rs10042486 and three in 5-HTR2A (rs6311, rs6313, and rs17289304 were genotyped by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using the Sequenom MassARRAY Analyzer 4 system. Results: There were 220 responders and 70 nonresponders (120 remissioners and 170 nonremissioners after 6 weeks of treatment. We found no association between any of the five 5-HTR1A and 5-HTR2A gene polymorphisms and antidepressant drug response or remission (P>0

  9. Tokamak Fusion Core Experiment: design studies based on superconducting and hybrid toroidal field coils. Design overview

    Energy Technology Data Exchange (ETDEWEB)

    Flanagan, C.A. (ed.)

    1984-10-01

    This document is a design overview that describes the scoping studies and preconceptual design effort performed in FY 1983 on the Tokamak Fusion Core Experiment (TFCX) class of device. These studies focussed on devices with all-superconducting toroidal field (TF) coils and on devices with superconducting TF coils supplemented with copper TF coil inserts located in the bore of the TF coils in the shield region. Each class of device is designed to satisfy the mission of ignition and long pulse equilibrium burn. Typical design parameters are: major radius = 3.75 m, minor radius = 1.0 m, field on axis = 4.5 T, plasma current = 7.0 MA. These designs relay on lower hybrid (LHRH) current rampup and heating to ignition using ion cyclotron range of frequency (ICRF). A pumped limiter has been assumed for impurity control. The present document is a design overview; a more detailed design description is contained in a companion document.

  10. CEA and AREVA R and D on HTR fuel fabrication and presentation of the CAPRI experimental manufacturing line

    Energy Technology Data Exchange (ETDEWEB)

    Charollais, Francois [CEA Cadarache, DEN/CAD/DEC/SPUA, Bat. 315, BP1, 13108 Saint Paul lez Durance (France)]. E-mail: francois.charollais@cea.fr; Fonquernie, Sophie [CEA Cadarache, DEN/CAD/DEC/SPUA, Bat. 315, BP1, 13108 Saint Paul lez Durance (France); Perrais, Christophe [CEA Cadarache, DEN/CAD/DEC/SPUA, Bat. 315, BP1, 13108 Saint Paul lez Durance (France); Perez, Marc [CEA Grenoble, DRT/GRE/DTEN/S3ME, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Dugne, Olivier [CEA Pierrelatte, DEN/VRH/DTEC/STCF/LMAC, BP 111, 26702 Pierrelatte (France); Cellier, Francois [Framatome ANP , Plants Sector, 10 rue Juliette Recamier, 69456 Lyon Cedex 06 (France); Harbonnier, Gerard [CERCA, BP 1114, 26104 Romans sur Isere Cedex (France); Vitali, Marie-Pierre [CERCA , BP 1114, 26104 Romans sur Isere Cedex (France)

    2006-03-15

    In the framework of the French V/HTR fuel development and qualification program, the Commissariat a l'Energie Atomique (CEA) and AREVA are conducting R and D projects covering the mastering of UO{sub 2} coated particle and fuel compact fabrication technology. To fulfill this task, a review of past knowledge, of existing technologies and a preliminary laboratory-scale work program have been conducted with the aim of retrieving the know-how on HTR coated particle and compact manufacture: - The different stages of UO{sub 2} kernel fabrication GSP process have been reviewed, reproduced and improved. - The experimental conditions for the chemical vapor deposition of coatings have been defined on dummy kernels and development of innovative characterization methods has been carried out.- Former CERCA compacting process has been reviewed and updated. In parallel, an experimental manufacturing line for coated particles, named GAIA, and a compacting line based on former CERCA compacting experience have been designed, constructed and are in operation since early 2005 at CEA Cadarache and CERCA Romans, respectively. These two facilities constitute the CAPRI line (CEA and AREVA PRoduction Integrated line). The major objectives of the CAPRI line are: - to recover and validate past knowledge, - to produce representative HTR TRISO fuel meeting industrial standards, - to permit the optimization of reference fabrication processes for kernels and coatings defined previously at a laboratory-scale and the investigation of alternative and innovative fuel design (UCO kernel, ZrC coating), - to test alternative compact process options and - to fabricate and characterize fuel required for irradiation and qualification purpose. This paper presents the status of progress of R and D conducted on HTR fuel particles and compact manufacture by early 2005 and the potential of the laboratory-scale HTR fuel CAPRI line.

  11. Gas reactor international cooperative program: HTR market assessments

    Energy Technology Data Exchange (ETDEWEB)

    Leeth, G.G.; Berkowitz, B.J.

    1979-09-01

    The HTR Multiplex utilizes the HTR as an energy source to produce multiple forms of energy. The multiplex technolog is applicable to the following markets: dispersed industrial heat; peaking and mid-range electricity; ammonia and methanol production with methane feedstock; and production of gaseous and liquid fuels from coal. It is estimated that the first two markets will comprise from 300 GW(+) to 400 GW(+) in the 2000 to 2020 time period (about 8 quads per year). For the dispersed industrial heat, the HTR multiplex has a heat cost about half that of fluidized bed combustors (FBC) operating at a capacity factor of 0.3 and about equal to that of FBC's operating at a capacity factor of 0.9. For the peaking and mid-range electric market, the HTR multiplex can supply electric energy at costs three-fourths that of FBC's operating at a capacity of 0.1 and equal to that of FBC's operating at a capacity factor of 0.3. For the ammonia and methanol markets, the HTR multiplex costs are about equal to coal and somewhat higher than methane with current fuel prices. Application to coal refining is similar to the ammonia and methanol markets. Current economic analyses show approximate equivalence for coal and nuclear heat.

  12. Improving the calculated core stability by the core nuclear design optimization

    Energy Technology Data Exchange (ETDEWEB)

    Partanen, P. [Teollisuuden Voima Oy, Olkiluoto (Finland)

    1995-12-31

    Three different equilibrium core loadings for TVO II reactor have been generated in order to improve the core stability properties at uprated power level. The reactor thermal power is assumed to be uprated from 2160 MW{sub th} to 2500 MW{sub th}, which moves the operating point after a rapid pump rundown where the core stability has been calculated from 1340 MW{sub th} and 3200 kg/s to 1675 MW{sub th} and 4000 kg/s. The core has been refuelled with ABB Atom Svea-100 -fuel, which has 3,64% w/o U-235 average enrichment in the highly enriched zone. PHOENIX lattice code has been used to provide the homogenized nuclear constants. POLCA4 static core simulator has been used for core loadings and cycle simulations and RAMONA-3B program for simulating the dynamic response to the disturbance for which the stability behaviour has been evaluated. The core decay ratio has been successfully reduced from 0,83 to 0,55 mainly by reducing the power peaking factors. (orig.) (7 figs., 1 tab.).

  13. Variation in the HTR1A and HTR2A genes and social adjustment in depressed patients.

    Science.gov (United States)

    Antypa, Niki; Calati, Raffaella; Souery, Daniel; Pellegrini, Silvia; Sentissi, Othman; Amital, Daniela; Moser, Ulrike; Montgomery, Stuart; Kasper, Siegfried; Zohar, Joseph; De Ronchi, Diana; Mendlewicz, Julien; Serretti, Alessandro

    2013-09-05

    Social adjustment is impaired in depressed patients. The difficulty to adjust to social circumstances has been hypothesized to be one of the causes of depression, as well as a consequence of the disorder. Genetic variation in the serotonin transporter gene has been previously associated with social adjustment levels in patients with mood disorders. We investigated whether variations on the HTR1A (rs6295) and HTR2A (rs7997012) genes were associated with levels of social adjustment using the Social Adjustment Scale in two samples of depressed patients (total n=156). Patients carrying the GG genotype of the HTR2A-rs7997012 showed better social adjustment in areas of work and family unit bonding. These findings did not survive correction for multiple testing and should be interpreted with caution. Our finding is in line with previous observations that have associated the G allele of the HTR2A-rs7997012 with higher rate of antidepressant response. The HTR2A-rs7997012 is worthy of further investigation in studies examining factors that are related to depression course and outcome. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Gas reactor international cooperative program. HTR-synfuel application assessment

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    This study assesses the technical, environmental and economic factors affecting the application of the High Temperature Gas-Cooled Thermal Reactor (HTR) to: synthetic fuel production; and displacement of fossil fuels in other industrial and chemical processes. Synthetic fuel application considered include coal gasification, direct coal liquefaction, oil shale processing, and the upgrading of syncrude to motor fuel. A wide range of other industrial heat applications was also considered, with emphasis on the use of the closed-loop thermochemical energy pipeline to supply heat to dispersed industrial users. In this application syngas (H/sub 2/ +CO/sub 2/) is produced at the central station HTR by steam reforming and the gas is piped to individual methanators where typically 1000/sup 0/F steam is generated at the industrial user sites. The products of methanation (CH/sub 4/ + H/sub 2/O) are piped back to the reformer at the central station HTR.

  15. 76 FR 14825 - Core Principles and Other Requirements for Designated Contact Markets

    Science.gov (United States)

    2011-03-18

    ... COMMISSION 17 CFR Parts 1, 16, and 38 RIN 3038-AD09 Core Principles and Other Requirements for Designated... Commission in the Federal Register release for the notice of proposed rulemaking for ``Core Principles and... comment period for the proposed rulemaking closed on February 22, 2011. \\2\\ See Core Principles and Other...

  16. 78 FR 32988 - Core Principles and Other Requirements for Designated Contract Markets; Correction

    Science.gov (United States)

    2013-06-03

    ... COMMISSION 17 CFR Part 38 RIN 3038-AD09 Core Principles and Other Requirements for Designated Contract...: This document corrects the Federal Register release of the final rule regarding Core Principles and... language for the previously published Federal Register release of the final rule regarding Core Principles...

  17. Design of low-loss and highly birefringent hollow-core photonic crystal fiber

    DEFF Research Database (Denmark)

    Roberts, Peter John; Williams, D.P.; Sabert, H.

    2006-01-01

    A practical hollow-core photonic crystal fiber design suitable for attaining low-loss propagation is analyzed. The geometry involves a number of localized elliptical features positioned on the glass ring that surrounds the air core and separates the core and cladding regions. The size of each fea...

  18. Design of the Face/Core Interface for Improved Fracture Resistance

    DEFF Research Database (Denmark)

    Lundsgaard-Larsen, Christian; Berggreen, Christian; Carlsson, Leif A.

    2008-01-01

    This study investigates the face/core fracture behavior of sandwich specimens with different designs. The traditional interface with a quadraxial mat directly adhered to the foam core is compared to interfaces where an additional mat with randomly oriented fibers is inserted between core and face...

  19. Assignment of the 5HT7 receptor gene (HTR7) to chromosome 10q and exclusion of genetic linkage with Tourette syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Gelernter, J.; Rao, P.A.; Pauls, D.L. [Yale Univ. School of Medicine, West Haven, CT (United States)] [and others

    1995-03-20

    A novel serotonin receptor designated 5HT7 (genetic locus HTR7) was cloned in 1993. This receptor has interesting properties related to ligand affinity and CNS distribution that render HTR7 a very interesting candidate gene for neuropsychiatric disorders. We mapped this gene, first by physical methods and then by genetic linkage. First, we made a tentative assignment to chromosome 10, based on hybridization of an HTR7 probe to a Southern blot of DNA from somatic cell hybrids. We then identified a genetic polymorphism at the HTR7 locus. We identified one extended pedigree where the polymorphism segregated. Using the LEPED computer program for pairwise linkage analysis, we confirmed the assignment of the gene to chromosome 10, specifically 10q21-q24, based on a lod score of 5.37 at 0% recombination between HTR7 and D10S20 (a chromosome 10 reference marker). Finally, we excluded genetic linkage between this locus and Tourette syndrome under a reasonable set of assumptions. 15 refs., 1 fig., 1 tab.

  20. Feasibility study on nuclear core design for soluble boron free small modular reactor

    Energy Technology Data Exchange (ETDEWEB)

    Rabir, Mohamad Hairie, E-mail: m-hairie@nuclearmalaysia.gov.my; Hah, Chang Joo; Ju, Cho Sung [Department of NPP Engineering, KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-04-29

    A feasibility study on nuclear core design of soluble boron free (SBF) core for small size (150MWth) small modular reactor (SMR) was investigated. The purpose of this study was to design a once through cycle SMR core, where it can be used to supply electricity to a remote isolated area. PWR fuel assembly design with 17×17 arrangement, with 264 fuel rods per assembly was adopted as the basis design. The computer code CASMO-3/MASTER was used for the search of SBF core and fuel assembly analysis for SMR design. A low critical boron concentration (CBC) below 200 ppm core with 4.7 years once through cycle length was achieved using 57 fuel assemblies having 170 cm of active height. Core reactivity controlled using mainly 512 number of 4 wt% and 960 12 wt% Gd rods.

  1. Feasibility study on nuclear core design for soluble boron free small modular reactor

    Science.gov (United States)

    Rabir, Mohamad Hairie; Hah, Chang Joo; Ju, Cho Sung

    2015-04-01

    A feasibility study on nuclear core design of soluble boron free (SBF) core for small size (150MWth) small modular reactor (SMR) was investigated. The purpose of this study was to design a once through cycle SMR core, where it can be used to supply electricity to a remote isolated area. PWR fuel assembly design with 17×17 arrangement, with 264 fuel rods per assembly was adopted as the basis design. The computer code CASMO-3/MASTER was used for the search of SBF core and fuel assembly analysis for SMR design. A low critical boron concentration (CBC) below 200 ppm core with 4.7 years once through cycle length was achieved using 57 fuel assemblies having 170 cm of active height. Core reactivity controlled using mainly 512 number of 4 wt% and 960 12 wt% Gd rods.

  2. CORE

    DEFF Research Database (Denmark)

    Krigslund, Jeppe; Hansen, Jonas; Hundebøll, Martin

    2013-01-01

    different flows. Instead of maintaining these approaches separate, we propose a protocol (CORE) that brings together these coding mechanisms. Our protocol uses random linear network coding (RLNC) for intra- session coding but allows nodes in the network to setup inter- session coding regions where flows...... intersect. Routes for unicast sessions are agnostic to other sessions and setup beforehand, CORE will then discover and exploit intersecting routes. Our approach allows the inter-session regions to leverage RLNC to compensate for losses or failures in the overhearing or transmitting process. Thus, we...... increase the benefits of XORing by exploiting the underlying RLNC structure of individual flows. This goes beyond providing additional reliability to each individual session and beyond exploiting coding opportunistically. Our numerical results show that CORE outperforms both forwarding and COPE...

  3. Transient performance and design aspects of low boron PWR cores with increased utilization of burnable absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Papukchiev, Angel [GRS mbH Forschungsinstitute, Garching (Germany); Schaefer, Anselm [ISaR GmbH, Garching (Germany)

    2008-07-01

    In conventional pressurized water reactor (PWR) designs, soluble boron is used for reactivity control over core fuel cycle. As high boron concentrations have significant impact on reactivity feedback properties and core transient behaviour, design changes to reduce boron concentration in the reactor coolant are of general interest in view of improving PWR inherent safety. In order to assess the potential advantages of such strategies in current PWRs, two low boron core configurations based on fuel with increased utilization of gadolinium and erbium burnable absorbers have been developed. The new PWR designs permit to reduce the natural boron concentration in reactor coolant at begin of cycle to 518 (Gd) and 805 (Er) ppm. An innovative low boron core design methodology was implemented combining a simplified reactivity balance search procedure with a core design approach based on detailed 3D diffusion calculations. Fuel cross sections needed for nuclear libraries were generated using the 2D lattice code HELIOS [2] and full core configurations were modelled with the 3D diffusion code QUABOX/CUBBOX [3]. For dynamic 3D calculations, the coupled code system ATHLET - QUABOX/CUBBOX was used [4]. The new cores meet German acceptance criteria regarding stuck rod, departure from nucleate boiling ratio (DNBR), shutdown margin, and maximal linear power. For the assessment of potential safety advantages of the new cores, comparative analyses were performed for three PWR core designs: the already mentioned two low boron designs and a standard design. The improved safety performance of the low boron cores in anticipated transients without scram (ATWS), boron dilution scenarios and beyond design basis accidents (BDBA) has already been reported in [1, 2 and 3]. This paper gives a short reminder on the results obtained. Moreover, it deals not only with the potential advantages, but also addresses the drawbacks of the new PWR configurations - complex core design, increased power

  4. Polymer Design and Processing for Liquid-Core waveguides

    DEFF Research Database (Denmark)

    Sagar, Kaushal Shashikant

    precursor material. Upon attaining thermodynamically stable gyroid phase segregation, nanoporosity is induced by chemically removing PDMS, the so-called sacrificial block. The isotropic nanoporosity in the polymer is utilized in fabricating a novel type of waveguides for opto-fluidic applications, which we...... call solid-liquid core waveguides, shortly SLCW. The high refractive index core of a SLCW consists of nanoporous polymer (solid) rendered hydrophilic and filled with water (liquid), while the low refractive index cladding consists of air-filled hydrophobic nanoporous polymer. Under conditions of total...... internal reflection, light is confined within the solid-liquid core. Controlled regions of the originally hydrophobic nanoporous 1,2-PB are rendered hydrophilic by photochemical modification of the polymer in the presence of photolithographic masks. In contact with water the hydrophilic regions...

  5. Current directions in core-shell nanoparticle design

    Science.gov (United States)

    Schärtl, Wolfgang

    2010-06-01

    Ten years ago I wrote a review about the important field of core-shell nanoparticles, focussing mainly on our own work about tracer systems, and briefly addressing polymer-coated nanoparticles as fillers for homogeneous polymer-colloid composites. Since then, the potential use of core-shell nanoparticles as multifunctional sensors or potential smart drug-delivery vehicles in biology and medicine has gained more and more importance, affording special types of multi-functionalized and bio-compatible nanoparticles. In this new review article, I try to address the most important developments during the last ten years. This overview is mainly based on frequently cited and more specialized recent review articles from leaders in their respective field. We will consider a variety of nanoscopic core-shell architectures from highly fluorescent nanoparticles (NPs), protected magnetic NPs, multifunctional NPs, thermoresponsive NPs and biocompatible systems to, finally, smart drug-delivery systems.Ten years ago I wrote a review about the important field of core-shell nanoparticles, focussing mainly on our own work about tracer systems, and briefly addressing polymer-coated nanoparticles as fillers for homogeneous polymer-colloid composites. Since then, the potential use of core-shell nanoparticles as multifunctional sensors or potential smart drug-delivery vehicles in biology and medicine has gained more and more importance, affording special types of multi-functionalized and bio-compatible nanoparticles. In this new review article, I try to address the most important developments during the last ten years. This overview is mainly based on frequently cited and more specialized recent review articles from leaders in their respective field. We will consider a variety of nanoscopic core-shell architectures from highly fluorescent nanoparticles (NPs), protected magnetic NPs, multifunctional NPs, thermoresponsive NPs and biocompatible systems to, finally, smart drug-delivery systems

  6. Genetic and bibliographic information: HTR2B [GenLibi

    Lifescience Database Archive (English)

    Full Text Available HTR2B 5-hydroxytryptamine (serotonin) receptor 2B human alcoholism (MeSH) Disorders... of Environmental Origin (C21) > Substance-Related Disorders (C21.739) > Alcohol-Related Disorders (C21.739.100) > Alcoholism (C21.739.100.250) 01A0634580 ...

  7. Assessment of LWR-HTR-GCFR Integrated Cycle

    Directory of Open Access Journals (Sweden)

    Eleonora Bomboni

    2009-01-01

    Full Text Available Preliminary analyses already performed showed that innovative GCRs, both thermal and fast, are very promising candidate to reach the Gen-IV sustainability goal. The integrated LWR-HTR-GCFR basically aims at closing the current nuclear fuel cycle: in principle, thanks to the unique characteristics of Helium coolant reactors, LWR SNF along with DU become valuable material to produce energy. Additionally, burning HMs of LWR SNF means not only a drastic reduction in the Unat demand but also a remarkable decrease in the long-term radiotoxic component of nuclear waste to be geologically stored. This paper focuses on the analyses of the LWR-HTR-GCFR cycle performed by the University of Pisa in the frame of the EU PUMA project (6th FP. Starting from a brief outline of the main characteristics of HTR and GCFR concepts and of the advantages of linking LWR, HTR and GCFR in a symbiotic way, this paper shows the integrated cycle involving a typical LWR (1000 MWe, a PBMR (400 MWth and a GCFR-“E” (2400 MWth. Additionally, a brief overview of the main technological constraints concerning (Pu+MA-based advanced fuels is given, in order to explain and justify the choices made in the framework of the considered cycle. Thereafter, calculations performed and results obtained are described.

  8. Design of an Air-Core HTS quadruple triplet for a heavy ion accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhan; Wei, Shaoqing; Lee, Sang Jin [Uiduk University, Gyeongju (Korea, Republic of)

    2016-12-15

    In recent years, high-temperature superconductor (HTS) Quadruple Triplets are being developed for heavy ion accelerators, because the HTS magnets are suitable to withstand radiation and high heat loads in the hot cell of accelerators. Generally, an iron yoke, which costs a mass of material, was employed to enhance the magnetic field when a quadrupole magnet was designed. The type of the magnet is called iron-dominated magnet, because the total magnetic field was mainly induced by the iron. However, in the HTS superconductor iron-dominated magnets, the coil-induced field also can have a certain proportion. Therefore, the air-core HTS quadrupole magnets can be considered instead of the iron-core HTS quadrupole magnet to be employed to save the iron material. This study presents the design of an air-core HTS quadruple triplet which consists three by air-core HTS quadruple magnet and compare the design result with that of an iron-core HTS quadruple triplet. First, the characteristics of an air-core HTS quadrupole magnet were analyzed to select the magnet system for the magnetic field uniformity impairment. Then, the field uniformity was improved(< 0.1%) exactly using evolution strategy (ES) method for each iron-core HTS quadrupole magnet and the air-core HTS quadruple triplet was established. Finally, the designed air-core triplet was compared with the iron-core HTS quadruple triplet, and the results of beam trajectories were presented with both the HTS quadruple triplet systems to show that the air-core triplet can be employed instead of the iron-core HTS triplet. The design of the air-core quadruple triplet was suggested for a heavy ion accelerator.

  9. Modified Anchor Shaped Post Core Design for Primary Anterior Teeth

    Directory of Open Access Journals (Sweden)

    R. Rajesh

    2014-01-01

    Full Text Available Restoring severely damaged primary anterior teeth is challenging to pedodontist. Many materials are tried as a post core but each one of them has its own drawbacks. This a case report describing a technique to restore severely damaged primary anterior teeth with a modified anchor shaped post. This technique is not only simple and inexpensive but also produces better retention.

  10. Teaching to the Common Core by Design, Not Accident

    Science.gov (United States)

    Phillips, Vicki; Wong, Carina

    2012-01-01

    The Bill & Melinda Gates Foundation has created tools and supports intended to help teachers adapt to the Common Core State Standards in English language arts and mathematics. The tools seek to find the right balance between encouraging teachers' creativity and giving them enough guidance to ensure quality. They are the product of two years of…

  11. Design of core--shell-type nanoparticles carrying stable radicals in the core.

    Science.gov (United States)

    Yoshitomi, Toru; Miyamoto, Daisuke; Nagasaki, Yukio

    2009-03-09

    Utilizing the self-assembled core-shell-type polymeric micelle technique, high-performance nanoparticles possessing stable radicals in the core and reactive groups on the periphery were prepared. The anionic ring-opening polymerization of ethylene oxide (EO) was carried out using potassium 3,3-diethoxypropanolate as an initiator, followed by mesylation with methanesulfonyl chloride to obtain acetal-poly(ethylene glycol)-methanesulfonate (acetal-PEG-Ms; 1). Compound 1 was reacted with potassium O-ethyldithiocarbonate, followed by treatment with n-propylamine to obtain heterobifunctional PEG derivatives containing both sulfanyl and acetal terminal groups (acetal-PEG-SH) (2) in a highly selective and quantitative manner. Poly(ethylene glycol)-block-poly(chloromethylstyrene) (acetal-PEG-b-PCMS) (3) was synthesized by the free-radical telomerization of chloromethylstyrene (CMS) using 2 as a telogen. The chloromethyl groups in the PCMS segment of the block copolymer (3) were quantitatively converted to 2,2,6,6-tetramethylpiperidinyloxys (TEMPOs) via the amination of 3 with 4-amino-TEMPO to obtain acetal-PEG-b-PCMS containing TEMPO moieties (4). The obtained 4 formed core-shell-type nanoparticles in aqueous media when subjected to the dialysis method: the cumulant average diameter of the nanoparticles was about 40 nm, and the nanoparticles emitted intense electron paramagnetic resonance (EPR) signals. The TEMPO radicals in the core of the nanoparticles showed reduction resistance even in the presence of 3.5 mM ascorbic acid. This means that these nanoparticles are anticipated as high-performance bionanoparticles that can be used in vivo.

  12. The primary loop confinement and pressure boundary system of the HTR-10

    Energy Technology Data Exchange (ETDEWEB)

    He Shuyan; Zhang Zhengming E-mail: zhengmin@inet.tsinghua.edu.cn; Qin Zhenya

    2002-10-01

    The design philosophy and requirements of the HTR-10 reactor building and the primary loop confinement are introduced in this paper. Also introduced are the design, fabrication and the installation of the HTR-10 primary loop pressure boundary system. The primary loop confinement comprises the sealed cavities of the reinforced concrete structure. The main components and the connected gas systems of the primary loop pressure boundary system are contained in the confinement. Under normal operating condition, the inside pressure of the confinement is kept at negative pressure to ensure the sealing function of the confinement. There is a rupture disk of overpressure protection in the confinement wall. After a depressurization accident the pressure of the confinement increases and the rupture disk will break. The air of the confinement is discharged directly to the atmosphere through the accident discharge chimney which is connected to the rupture disk without filter. The main components of the primary loop pressure boundary system consist of the reactor pressure vessel, the steam generator pressure vessel and the hot gas duct vessel. All the above main components are installed in the reactor cavity and the steam generator cavity. They are all nuclear safety class 1 components, whose materials production, design, fabrication, and tests are carried out according to ASME Section III and relevant Chinese nuclear codes.

  13. Development of core design/analyses technology for integral reactor - Monte Carlo code development for nuclear core analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chang Hyo; Jang, Chang Sun; Hong, In Seob; Jeong, Jong Seong [Seoul National University, Seoul (Korea)

    2000-03-01

    The objective of this project is to develope Monte Carlo code (named MCNAP) designed exclusively for neutronics analysis. The Monte Carlo method serves an effective numerical experiments for a new type of fuel pins, assemblies, reactor cores, etc. that lack experiments for a new type of fuel pins, assemblies, reactor cores, etc. that lack experimental measurements on their performance characteristics. The major research contents of this projects are to analyze a state-of-art analysis of Monte Carlo method, to draw up the specifications of the Monte Carlo code in terms of computational modules, and to develop Monte Carlo computational modules for predictions of major neutronics characteristics. The qualification of the MCNAP is examined though verification computations against fast and thermal integral experiments, k-effective and pin power distribution measurements of uranium and plutonium bearing VENUS cores, the design analysis of fuel assemblies and the core of Yonggwang unit 3 PWR. The numerical results of these verification calculations are presented in the main text. For the prospective user of the MCNAP, the user manual of the MCNAP is included in the main text of this report. 35 refs., 60 figs., 40 tabs. (Author)

  14. Design, Manufacture, and Operation of a Core Barrel for the Iceland Deep Drilling Project (IDDP

    Directory of Open Access Journals (Sweden)

    Guðmundur Ómar Friðleifsson

    2010-10-01

    Full Text Available The science program of the Iceland Deep Drilling Project (IDDP requires as much core as possible in the transition zone to supercritical and inside the supercritical zone (>374°C, in the depth interval 2400–4500 m. The spot coring system selected has a 7 ¼" (184.15 mm OD at 10 m length and collects a 4" (101.6 mm diameter core using an 8 ½" (215.9 mm OD core bit. It incorporates design characteristics, materials, clearances and bearings compatible with operation of the core barrel at temperatures as high as 600°C. Special attention was given to the volume of flushing which could be applied to the core barrel and through the bit while running in and out of the borehole and while coring. In November 2008 a successful spot coring test using the new core barrel was performed at 2800 m depth in the production well RN-17 B at Reykjanes, Iceland, where the formation temperature is 322°C. A 9.3-m hydrothermally altered hyaloclastite breccia was cored with 100% core recovery, in spite of it being highly fractured. A core tube data logger was also designed and placed inside the inner barrel to monitor the effectiveness of cooling. The temperature could be maintained at 100°C while coring, but it reached 170°C for a very short period while tripping in. The effective cooling is attributed to the high flush design and a top drive being employed, which allows circulation while tripping in or out, except for the very short time when a new drill pipe connectionis being made.

  15. CEA and AREVA R and D on V/HTR fuel fabrication with the CAPRI experimental manufacturing line

    Energy Technology Data Exchange (ETDEWEB)

    Charollais, Francois; Fonquernie, Sophie; Perrais, Christophe [DEN/CAD/DEC/SPUA, CEA, Centre de Cadarache, F-13108 Saint Paul lez Durance (France); Perez, Marc [DRT/GRE/DTEN/S3ME, CEA Grenoble, 17 rue des Martyrs, 38054 Grenoble cedex 9 (France); Cellier, Francois [FRAMATOME ANP, 10, rue Juliette Recamier, F-69456 Lyon cedex (France); Vitali, Marie-Pierre [CERCA Romans, FRAMATOME ANP, 10, rue Juliette Recamier, F-69456 Lyon cedex (France)

    2006-07-01

    In the framework of the French V/HTR fuel development and qualification program, the Commissariat a l'Energie Atomique (CEA) and AREVA through its program called ANTARES (Areva New Technology for Advanced Reactor Energy Supply) conduct R and D projects covering the mastering of UO{sub 2} coated particle and fuel compact fabrication technology. To fulfill this task, a review of past knowledge, of existing technologies and a preliminary laboratory scale work program have been conducted with the aim of retrieving the know-how on HTR coated particle and compact manufacture: - The different stages of UO{sub 2} kernel fabrication GSP Sol-Gel process have been reviewed, reproduced and improved; - The experimental conditions for the chemical vapour deposition (CVD) of coatings have been defined on dummy kernels and development of innovative characterization methods has been carried out; - Former CERCA compacting process has been reviewed and updated. In parallel, an experimental manufacturing line for coated particles, named GAIA, and a compacting line based on former CERCA compacting experience have been designed, constructed and are in operation since early 2005 at CEA Cadarache and CERCA Romans, respectively. These two facilities constitute the CAPRI line (CEA and AREVA PRoduction Integrated line). The major objectives of the CAPRI line are: - to recover and validate past knowledge; - to permit the optimisation of reference fabrication processes for kernels and coatings and the investigation of alternative and innovative fuel design (UCO kernel, ZrC coating); - to test alternative compact process options; - to fabricate and characterize fuel required for irradiation and qualification purpose; - to specify needs for the fabrication of representative V/HTR TRISO fuel meeting industrial standards. This paper presents the progress status of the R and D conducted on V/HTR fuel particle and compact manufacture by mid 2005. (authors)

  16. Design of full MOX core in ABWR; ABWR ni okeru furu MOX roshin no sekkei

    Energy Technology Data Exchange (ETDEWEB)

    Hirose, Tsutomu; Sasagawa, Masaru; Sakuma, Takanori [Hitavhi Ltd., Tokyo (Japan); Kinoshita, Yutaka

    1999-02-15

    A full MOX-ABWR, loaded with mixed-oxide (MOX) fuels of up to 100% of the core, is planned. Increased MOX fuel utilization will result in greater savings of uranium. Studies on the fuel rod thermal-mechanical design, the core design and the safety evaluation have been made, and the results are summarized in this paper. To sum it all up, the safety of the Full MOX-ABWR has been confirmed through design evaluations adequately considering the MOX fuel and core characteristics. (author)

  17. Designing Class Activities to Meet Specific Core Training Competencies: A Developmental Approach

    Science.gov (United States)

    Guth, Lorraine J.; McDonnell, Kelly A.

    2004-01-01

    This article presents a developmental model for designing and utilizing class activities to meet specific Association for Specialists in Group Work (ASGW) core training competencies for group workers. A review of the relevant literature about teaching group work and meeting core training standards is provided. The authors suggest a process by…

  18. Flexblue® core design: optimisation of fuel poisoning for a soluble boron free core with full or half core refuelling

    OpenAIRE

    Ingremeau Jean-Jacques; Cordiez Maxence

    2015-01-01

    Flexblue® is a 160 MWe, transportable and subsea-based nuclear power unit, operating up to 100 m depth, several kilometers away from the shore. If being underwater has significant safety advantages, especially using passive safety systems, it leads to two main challenges for core design. The first one is to control reactivity in operation without soluble boron because of its prohibitive drawbacks for a submerged reactor (system size, maintenance, effluents, and safety considerations). The sec...

  19. Preliminary Assessment of Two Alternative Core Design Concepts for the Special Purpose Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sterbentz, James W. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Werner, James E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hummel, Andrew J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kennedy, John C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); O' Brien, Robert C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Dion, Axel M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Richard N. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ananth, Krishnan P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-11-01

    The Special Purpose Reactor (SPR) is a small 5 MWt, heat pipe-cooled, fast reactor based on the Los Alamos National Laboratory (LANL) Mega-Power concept. The LANL concept features a stainless steel monolithic core structure with drilled channels for UO2 pellet stacks and evaporator sections of the heat pipes. Two alternative active core designs are presented here that replace the monolithic core structure with simpler and easier to manufacture fuel elements. The two new core designs are simply referred to as Design A and Design B. In addition to ease of manufacturability, the fuel elements for both Design A and Design B can be individually fabricated, assembled, inspected, tested, and qualified prior to their installation into the reactor core leading to greater reactor system reliability and safety. Design A fuel elements will require the development of a new hexagonally-shaped UO2 fuel pellet. The Design A configuration will consist of an array of hexagonally-shaped fuel elements with each fuel element having a central heat pipe. This hexagonal fuel element configuration results in four radial gaps or thermal resistances per element. Neither the fuel element development, nor the radial gap issue are deemed to be serious and should not impact an aggressive reactor deployment schedule. Design B uses embedded arrays of heat pipes and fuel pins in a double-wall tank filled with liquid metal sodium. Sodium is used to thermally bond the heat pipes to the fuel pins, but its usage may create reactor transportation and regulatory challenges. An independent panel of U.S. manufacturing experts has preliminarily assessed the three SPR core designs and views Design A as simplest to manufacture. Herein are the results of a preliminary neutronic, thermal, mechanical, material, and manufacturing assessment of both Design A and Design B along with comparisons to the LANL concept (monolithic core structure). Despite the active core differences, all three reactor concepts behave

  20. Flexblue® core design: optimisation of fuel poisoning for a soluble boron free core with full or half core refuelling

    Directory of Open Access Journals (Sweden)

    Ingremeau Jean-Jacques

    2015-01-01

    Full Text Available Flexblue® is a 160 MWe, transportable and subsea-based nuclear power unit, operating up to 100 m depth, several kilometers away from the shore. If being underwater has significant safety advantages, especially using passive safety systems, it leads to two main challenges for core design. The first one is to control reactivity in operation without soluble boron because of its prohibitive drawbacks for a submerged reactor (system size, maintenance, effluents, and safety considerations. The second one is to achieve a long cycle in order to maximise the availability of the reactor, because Flexblue® refuelling and maintenance will be performed in a shared support facility away from the production site. In this paper, these two topics are dealt with, from a neutronic point of view. Firstly, an overview of the main challenges of operating without soluble boron is proposed (cold shutdown, reactivity swing during cycle, load following, xenon stability. Secondly, an economic optimisation of the Flexblue® core size and cycle length is performed, using the QUABOX/CUBBOX code. Thirdly, the fuel enrichment and poisoning using gadolinium oxide are optimized for full core or half core refuelling, with the DRAGON code. For the specific case of the full core refuelling, an innovative heterogeneous configuration of gadolinium is used. This specific configuration is computed using a properly adapted state-of-the-art calculation scheme within the above-mentioned lattice code. The results in this specific configuration allow a reactivity curve very close to the core leakage one during the whole cycle.

  1. Computational fluid dynamic model for thermohydraulic calculation for the steady-state of the real scale HTR-1

    Energy Technology Data Exchange (ETDEWEB)

    Gamez, Abel; Rojas, Leorlen; Rosales, Jesus; Castro, Landy Y.; Gonzalez, Daniel; Garcia, Carlos, E-mail: agamezgmf@gmail.com, E-mail: leored1984@gmail.com, E-mail: jrosales@instec.cu, E-mail: lcastro@instec.cu, E-mail: danielgonro@gmail.com, E-mail: cgr@instec.cu [Instituto Superior de Tecnologias y Ciencias Aplicadas (InSTEC), La Habana (Cuba); Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Oliveira, Carlos B. de, E-mail: cabol@ufpe.br [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil); Dominguez, Dany S., E-mail: dsdominguez@gmail.com [Universidade Estadual de Santa Cruz (UESC), Ilheus, BA (Brazil)

    2015-07-01

    The high temperature gas cooled reactor (HTGR) is one of candidates of next generation of nuclear reactor according to IAEA report 2013. Evaluation of thermohydraulic performance and an experimental comparison results were proposed to the international research community. In this article, the tree dimensional CFD thermohydraulic modelation of steady state of HTR-10 modular reactor, using ANSYS CFX v14.0, has been done. Code-to-code and Code-to-experiment benchmark analyses, related to the testing program of the HTR-10 plant including steady state temperature distribution with the reactor at full power, were developed. The 3D real scale representation of reflector zone and fluid path flow inner and outer reflector blocks and cold helium cavity were carried out. The porous medium model was used to simulate the core zone in the reactor. The power distribution of the initial core published by IAEA-TECDOC-1694 obtained by Chief Scientific Investigators (CSIs) from China was used as heat sources in the core zone. (author)

  2. FFTF reload core nuclear design for increased experimental capability

    Energy Technology Data Exchange (ETDEWEB)

    Rothrock, R.B.; Nelson, J.V.; Dobbin, K.D.; Bennett, R.A.

    1976-01-01

    In anticipation of continued growth in the FTR experimental irradiations program, the enrichments for the next batches of reload driver fuel to be manufactured have been increased to provide a substantially enlarged experimental reactivity allowance. The enrichments for these fuel assemblies, termed ''Cores 3 and 4,'' were selected to meet the following objectives and constraints: (1) maintain a reactor power capability of 400 MW (based on an evaluation of driver fuel centerline melting probability at 15 percent overpower); (2) provide a peak neutron flux of nominally 7 x 10/sup 15/ n/cm/sup 2/-sec, with a minimum acceptable value of 95 percent of this (i.e., 6.65 x 10/sup 15/ n/cm/sup 2/-sec); and (3) provide the maximum experimental reactivity allowance that is consistent with the above constraints.

  3. Optimal design of plates with cell type hollow core

    Science.gov (United States)

    Frolovs, G.; Rocens, K.; Sliseris, J.

    2017-10-01

    This research relates to the composite sandwich plywood plates with skin layers of birch plywood and a core of straight and waved plywood cell-type ribs. This specific form of ribs allows to simplify manufacturing processes, to increase the glued area and the ways of load transferring paths and to tailor the stiffness in both (longitudinal and transversal) directions providing increased specific stiffness, strength or load bearing capacity (stiffness, strength or load bearing capacity to mass ratio). The various results depending on chosen variables (according to strength-stiffness criteria) were obtained for one span plate in bending. A various thicknesses of plywood sheets are taken for skins and straight rib parts while for waved part of ribs the 3 layer plywood was taken.

  4. Physics design of initial and approach to equilibrium cores of a reactor concept for thorium utilization

    Energy Technology Data Exchange (ETDEWEB)

    Pal, Usha [Light Water Reactor Physics Section, Reactor Physics Design Division, Bhabha Atomic Research Centre, A-5-15, Central Complex, Mumbai, Maharashtra (India)], E-mail: ushapal@barc.gov.in; Jagannathan, V. [Light Water Reactor Physics Section, Reactor Physics Design Division, Bhabha Atomic Research Centre, A-5-15, Central Complex, Mumbai, Maharashtra (India)], E-mail: vjagan@barc.gov.in

    2008-07-15

    A thermal reactor concept 'a thorium breeder reactor' (ATBR) was conceived and reported by the authors during 1998. The distinctive physical characteristics of ATBR core with different types of seed fuels have been discussed in subsequent publications. The equilibrium core of ATBR with Pu seed was shown to exhibit a flat and low excess reactivity for a fuel cycle duration of two years. Notably this is achieved by no conventional burnable poison but by intrinsic balancing of reactivity between fissile and fertile zones. In this paper we present the design of the initial core and the refueling strategy for subsequent fuel cycles to enable a smooth transition to the equilibrium core. Three fuel types with characteristics similar to the three batch fuels of equilibrium core were designed for the initial core. Fuel requirement for the initial core is 4673 kg of reactor grade (RG) Pu for a cycle length of two years at 1875 MWt as against the 2200 kg needed for each fuel cycle of equilibrium core for same quantum of energy. The core reactivity variation during the first fuel cycle is monotonic fall and is relatively high ({approx}40 mk) but gradually diminishes to {+-}5 mk for fuel cycles 5-8.

  5. Design of a reactor core in the Oma Full MOX-ABWR

    Energy Technology Data Exchange (ETDEWEB)

    Hama, Teruo [Electric Power Development Co. Ltd., Tokyo (Japan)

    1999-09-01

    The Electric Power Development Co., Ltd. has progressed a construction plan on an improved boiling-water reactor aiming at loading of MOX fuel in all reactor cores (full MOX-ABWR) at Oma-cho, Aomori prefecture, which is a last stage on application of approval on establishment at present. Here were described on outlines of reactor core in the full MOX-ABWR and its safety evaluation. For the full MOX-ABWR loading MOX fuel assembly into all reactor core, thermal and mechanical design analysis of fuel bars and core design analysis were conducted. As a result, it was confirmed that judgement standards in mixed core of MOX fuel and uranium fuel were also applicable as well as that in uranium fuel. (G.K.)

  6. Reactor core and plant design concepts of the Canadian supercritical water-cooled reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yetisir, M.; Gaudet, M.; Bailey, J.; Rhodes, D.; Guzonas, D.; Hamilton, H.; Haque, Z.; Pencer, J.; Sartipi, A. [Atomic Energy of Canada Limited, Chalk River, ON (Canada)

    2014-07-01

    Canada is developing a 1200 MWe supercritical water-cooled reactor (SCWR), which has evolved from the well-established pressure-tube type CANDU{sup 1} reactor. This SCWR reactor concept, which is often referred to as the Canadian SCWR, uses supercritical water as a coolant, has a low-pressure heavy water moderator and a direct cycle for power production. The reactor concept incorporates advanced safety features, such as passive emergency core cooling, long-term decay heat rejection to the environment and fuel melt prevention via passive moderator cooling. These features significantly reduce the core damage frequency beyond existing nuclear reactors. This paper presents a description of the Canadian SCWR core design concept, the integration of in-core and out-of-core components and the mechanical plant design concept. Supporting systems for reactor safety, reactor control and moderator cooling are also described. (author)

  7. Designing, Leading and Managing the Transition to the Common Core: A Strategy Guidebook for Leaders

    Science.gov (United States)

    Brown, Brentt; Vargo, Merrill

    2014-01-01

    The Common Core provides districts an opportunity to renew their focus on teaching and learning. But it also poses a number of design and implementation challenges for school districts. The "Leadership and Design Cycles" described in this guidebook offers an evidenced-based and structured process for leaders to design and implement…

  8. Introduction to Open Core Protocol Fastpath to System-on-Chip Design

    CERN Document Server

    Schwaderer, W David

    2012-01-01

    This book introduces Open Core Protocol (OCP), not as a conventional hardware communications protocol but as a meta-protocol: a means for describing and capturing the communications requirements of an IP core, and mapping them to a specific set of signals with known semantics.  Readers will learn the capabilities of OCP as a semiconductor hardware interface specification that allows different System-On-Chip (SoC) cores to communicate.  The OCP methodology presented enables intellectual property designers to design core interfaces in standard ways. This facilitates reusing OCP-compliant cores across multiple SoC designs which, in turn, drastically reduces design times, support costs, and overall cost for electronics/SoCs. Provides a comprehensive introduction to Open Core Protocol, which is more accessible than the full specification; Designed as a hands-on, how-to guide to semiconductor design; Includes numerous, real “usage examples” which are not available in the full specification; Integrates coverag...

  9. Gas core reactor power plants designed for low proliferation potential

    Energy Technology Data Exchange (ETDEWEB)

    Lowry, L.L. (comp.)

    1977-09-01

    The feasibility of gas core nuclear power plants to provide adequate power while maintaining a low inventory and low divertability of fissile material is studied. Four concepts were examined. Two used a mixture of UF/sub 6/ and helium in the reactor cavities, and two used a uranium-argon plasma, held away from the walls by vortex buffer confinement. Power levels varied from 200 to 2500 MWth. Power plant subsystems were sized to determine their fissile material inventories. All reactors ran, with a breeding ratio of unity, on /sup 233/U born from thorium. Fission product removal was continuous. Newly born /sup 233/U was removed continuously from the breeding blanket and returned to the reactor cavities. The 2500-MWth power plant contained a total of 191 kg of /sup 233/U. Less than 4 kg could be diverted before the reactor shut down. The plasma reactor power plants had smaller inventories. In general, inventories were about a factor of 10 less than those in current U.S. power reactors.

  10. Core and Refueling Design Studies for the Advanced High Temperature Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Holcomb, David Eugene [ORNL; Ilas, Dan [ORNL; Varma, Venugopal Koikal [ORNL; Cisneros, Anselmo T [ORNL; Kelly, Ryan P [ORNL; Gehin, Jess C [ORNL

    2011-09-01

    The Advanced High Temperature Reactor (AHTR) is a design concept for a central generating station type [3400 MW(t)] fluoride-salt-cooled high-temperature reactor (FHR). The overall goal of the AHTR development program is to demonstrate the technical feasibility of FHRs as low-cost, large-size power producers while maintaining full passive safety. This report presents the current status of ongoing design studies of the core, in-vessel structures, and refueling options for the AHTR. The AHTR design remains at the notional level of maturity as important material, structural, neutronic, and hydraulic issues remain to be addressed. The present design space exploration, however, indicates that reasonable options exist for the AHTR core, primary heat transport path, and fuel cycle provided that materials and systems technologies develop as anticipated. An illustration of the current AHTR core, reactor vessel, and nearby structures is shown in Fig. ES1. The AHTR core design concept is based upon 252 hexagonal, plate fuel assemblies configured to form a roughly cylindrical core. The core has a fueled height of 5.5 m with 25 cm of reflector above and below the core. The fuel assembly hexagons are {approx}45 cm across the flats. Each fuel assembly contains 18 plates that are 23.9 cm wide and 2.55 cm thick. The reactor vessel has an exterior diameter of 10.48 m and a height of 17.7 m. A row of replaceable graphite reflector prismatic blocks surrounds the core radially. A more complete reactor configuration description is provided in Section 2 of this report. The AHTR core design space exploration was performed under a set of constraints. Only low enrichment (<20%) uranium fuel was considered. The coated particle fuel and matrix materials were derived from those being developed and demonstrated under the Department of Energy Office of Nuclear Energy (DOE-NE) advanced gas reactor program. The coated particle volumetric packing fraction was restricted to at most 40%. The pressure

  11. Advanced PWR Core Design with Siemens High-Plutonium-Content MOX Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Dieter Porsch; Gerhard Schlosser; Hans-Dieter Berger

    2000-06-04

    The Siemens experience with plutonium recycling dates back to the late 1960s. Over the years, extensive research and development programs were performed for the qualification of mixed-oxide (MOX) technology and design methods. Today's typical reload enrichments for uranium and MOX fuel assemblies and modern core designs have become more demanding with respect to accuracy and reliability of design codes. This paper presents the status of plutonium recycling in operating high-burnup pressurized water reactor (PWR) cores. Based on actual examples, it describes the validation status of the design methods and stresses current and future needs for fuel assembly and core design including those related to the disposition of weapons-grade plutonium.

  12. Bioclimatic design as the core of environment programmes

    Energy Technology Data Exchange (ETDEWEB)

    Radovic, D. [University of Melbourne (Australia). Faculty of Architecture, Building and Planning

    1996-03-01

    There is recognised need for an integrated approach to new professional challenges of sustainability, and for coordination of all environment-related subjects within the curriculum of The University of Melbourne, Faculty of Architecture and Planning. The new Environment Programmes developed during 1993 and started in 1994 will offer courses on the theory and practice of sustainable urban and architectural design, with an emphasis on bioclimatic urban and architectural design. In addition, the Programme will engage in research on the development of environment-responsive, regional approaches to urbanism and architecture in different parts of Australia, the Pacific region and throughout the world, implementing research results with practical design work. This paper presents: (i) the curriculum itself; (ii) the basic organisational and educational principles and ideas behind the course; (iii) its parallel programmes based on interdisciplinary and international collaboration, and (iv) describes an attitude to educate architects capable to contribute to the generation of a specific, environmentally generated regionalism in future Australian architectrue. The Energy and Environmental Programme`s curriculum was fully defined in December 1993, and gradually introduced during 1994. The first full undergraduate cycle started in 1995. (orig.)

  13. Simulation of the Long period Core Design for WH type of KHNP

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ji-Eun; Moon, Sang-Rae [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2016-10-15

    The current core design of the reactor and the new design of long period based on ANC code are compared here targeting the unit of WH type(Westinghouse nuclear steam supply system) operated by KHNP. The reactor core is composed of 157 fuel assemblies, consisting of a 17×17 array with 264 fuel rods, 24 guide thimbles. To investigate susceptibility of CIPS(crud-induced power shift) for long period core design, the boron mass is also calculated here. The long period core design for WH type of KHNP is simulated and evaluated the risk assessment for the result. 89 feed assemblies and 4.95w/o uranium enrichment (3.2w/o for Axial-blanket) are used for fresh fuel rods. The cycle length of long period design is increased by 6 month than the average of operated cycles satisfying the criteria of risk assessment for the core design; maximum F△h and maximum pin burnup and so on, except burndown curve.

  14. Management of Grossly Decayed Mandibular Molar with Different Designs of Split Cast Post and Core

    Directory of Open Access Journals (Sweden)

    Rashmi Bansal

    2016-01-01

    Full Text Available Mandibular molar with extensive loss of tooth structure, especially where no cavity wall is remaining, and insertion of posts in both the roots appear necessary so as to achieve proper retention for the core material. A single unit metal casting with two posts, one in the mesial root and the other in the distal divergent root, is difficult to fabricate due to difference in the path of insertion of the two posts. Multisection post and core or single cast post and core with auxiliary post can be an effective design to manage grossly decayed mandibular molars.

  15. Fuel management and core design code systems for pressurized water reactor neutronic calculations

    Energy Technology Data Exchange (ETDEWEB)

    Ahnert, C.; Arayones, J.M.

    1985-06-01

    A package of connected code systems for the neutronic calculations relevant in fuel management and core design has been developed and applied for validation to the startup tests and first operating cycle of a 900MW (electric) PWR. The package includes the MARIA code system for the modeling of the different types of PWR fuel assemblies, the CARMEN code system for detailed few group diffusion calculations for PWR cores at operating and burnup conditions, and the LOLA code system for core simulation using onegroup nodal theory parameters explicitly calculated from the detailed solutions.

  16. A Comparative Physics Study on Low Boron Concentration Small PWR Core Designs using Different Reflectors

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Ho Seong; Hong, Ser Gi [Kyung Hee University, Yongin (Korea, Republic of)

    2015-10-15

    In this work, we considered not only water reflector but also several different solid reflectors for this purpose. In this work, we performed the comparative physics study on the long cycle small PWR core with the several different reflector assemblies. A reference core having water reflector was designed to have low boron concentration by using new FCM burnable poison rods with B4C kernel BISO particles. Then, the comparative study was performed by replacing the water reflector with the candidate reflector compositions in the reference core. The SMRs have been designed to simplify the system components so as to improve passive safety by integrating the main system components into reactor vessel with the removal of valves and pipes. Korea also has supported a project for designing the light water cooled SMR which can be operated without soluble boron or low boron concentration. As a part of this project, we have designed an advanced light water cooled SMR core with new Fully Ceramic Micro-encapsulated(FCM) burnable poison rods (BPR) which can be operated over 4 EFPYs with low boron concentration (<350 ppm). The objective of this work is to analyze the effects of different radial reflector materials on the performances of our SMR core having FCM BPRs because it is considered interesting to know how long we can extend the cycle length of the SMR core by optimizing the reflector design. Also, to improve the accuracy of the reflector homogenized two-group cross sections, we performed two-dimensional whole core transport calculations with DeCART2D to obtain the detailed spectrum of the reflector and used it in producing the reflector homogenized two-group cross sections. The study showed that the reference water reflected core has the shortest cycle length of 3.5 EFPYs and the lowest boron concentration of 221ppm while the other solid reflected cores have significantly longer cycle lengths but higher boron concentrations. Of the cores, the graphite reflected core has

  17. Validation results for AREVA NP's next generation core design system ARCADIA {sup registered}

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Bettina [AREVA NP, Erlangen (Germany); Lonchampt, Jeremy [AREVA NP, Lyon (France); Plancher, Johann [AREVA NP, Paris (France); Segard, Kevin [AREVA NP, Lynchburg, VA (United States)

    2010-05-15

    With ARCADIA {sup registered}, AREVA NP is currently developing a next generation core design system to meet customer's current expectations and anticipate future demands. ARCADIA {sup registered} 's computational core are the spectral code APOLLO2-A (based on APOLLO-2 from the Commissariat a l'Energie Atomique (CEA), France and adapted by AREVA NP for industrial applications) and the core simulator ARTEMIS. These codes are imbedded inside a shell of Integration and Business Services named LADON, acting as the ultimate working environment for the end-user and featuring a modern look-and-feel graphical user interface. The spectral code APOLLO2-A is used for neutronic fuel assembly design and for the generation of cross sections libraries used in ARTEMIS. Its main characteristics are a 281-group energy mesh, the use of the state-of-the-art Method of Characteristics (MOC) and the availability of more than 300 nuclides for explicit representation. It is also capable of calculating colorsets. The core simulator ARTEMIS represents AREVA NP's future 3D coupled neutronics/thermal-hydraulics/thermal-mechanics code system for steady-state and transient core design, with COBRA-FLX used as thermal-hydraulic module and a thermal-mechanics model consistent to COPERNIC. ARTEMIS will allow for both standard diffusion as well as advanced pin-by-pin transport calculations. Programmed using a UML (Unified Modeling Language) driven approach, ARTEMIS provides advanced numeric algorithms as well as improved flux solver performance and robustness. Although ARTEMIS was developed originally for PWR applications, the code is designed to be extended to support future BWR applications as well, e.g. with respect to control rod modeling and enhanced thermal-hydraulics core description. The complete core design system has been validated for a large number of cycle calculations of several German and foreign reactors. Some highlights of these calculations validation will be

  18. Studi Fleksibilitas dan Posibilitas Daur Bahan Bakar Reaktor Temperatur Tinggi (HTR

    Directory of Open Access Journals (Sweden)

    Hery Adrial

    2017-03-01

    Full Text Available Dewasa ini sejumlah institusi riset di dunia sedang mengembangkan teknologi reaktor temperatur tinggi (HTR melalui berbagai program seperti PUMA, RAPHAEL, ANTARES, dll. Tujuan dari program ini adalah untuk mengembangkan HTR versi demontrasi dan komersial. HTR merupakan reaktor berpendingin gas temperatur tinggi, bermoderator grafit dengan spektrum neutron termal dan temperatur outlet teras hingga 1.000oC. Fasilitas energi ini dapat mencapai efisiensi termodinamika yang cukup tinggi (~80% dengan kapabilitas generasi listrik dan produksi hidrogen. Makalah ini membahas fleksibilitas dan posibilitas daur bahan bakar HTR yang meliputi serangkaian daur bahan bakar komprehensif. Dikategorikan ke dalam 4 kelompok, yaitu daur bahan bakar uranium pengkayaan rendah (LEU, daur bahan bakar MOX, daur bahan bakar hanya plutonium dan daur bahan bakar berbasis thorium, daur bahan bakar HTR dievaluasi secara sistematis. Makalah ini juga mendiskusikan pertimbangan pemilihan daur bahan bakar untuk sejumlah HTR yang telah dioperasikan seperti AVR dan THTR Jerman, Peach Bottom dan Fort Saint Vrain USA, DRAGON Inggris, dll., dan yang sedang dalam proses desain seperti HTR AREVA Perancis, PBMR Afrika Selatan, dll. Hasil diskusi menyimpulkan bahwa daur LEU layak dipilih sebagai daur referensi untuk proyek HTR masa kini dan masa yang akan datang.

  19. Design and realization of the IP control core in field controllers for LAMOST spectroscopes

    Science.gov (United States)

    Wang, Jianing; Han, Zhongyi; Zeng, Yizhong; Dai, Songxin; Hu, Zhongwen; Zhu, Yongtian; Wang, Lei; Hou, Yonghui

    2010-07-01

    The China-made telescope, LAMOST, consists of 16 spectroscopes to detect stellar spectra via 4000 optical fibers. In each spectroscope, many movable parts work in phase. Those parts are real-time controlled and managed by field controllers based on FPGA. This paper mainly introduces how to use DSP Builder module library in MATLAB / Simulink to construct the IP control core on FPGA chip. This method can also be used to design the control core of PID arithmetic, to carry out arithmetic simulation and generate VHDL language file, as well as to integrate it into SOPC developing environment so as to repeatedly use. In this way, the design period of the control system may be shortened and design process simplified. Finally due to the reversibility and programmability of the IP control core ,a system on a chip for field controllers of spectroscope is realized, which meets astronomical control requirements, providing an effective scheme for embedded system in astronomical instrument applications.

  20. Nuclear cogeneration based on HTR technology

    Energy Technology Data Exchange (ETDEWEB)

    Haverkate, B.R.W.; Van Heek, A.I.; Jehee, J.N.T

    1998-03-01

    The Dutch market for combined generation of heat and power identifies a unit size of 40 MW thermal for the conceptual design of an Inherently safe Nuclear COGENeration plant (INCOGEN). Technical, economical and licensing issues have been investigated of the INCOGEN design which comprises pebble fuel cooled by helium, and directly coupled with a helium compressor and turbine. Thermohydraulic and reactor physics analyses show favourable control characteristics during normal operation and a benign response to loss of helium coolant and loss of flow conditions. Throughout the response on these highly infrequent conditions, ample margin exists between the highest fuel temperatures and the temperature above which fuel degradation will occur. 7 refs.

  1. Transformer design principles with applications to core-form power transformers

    CERN Document Server

    Del Vecchio, Robert M

    2010-01-01

    Updating and reorganizing the valuable information in the first edition to enhance logical development, Transformer Design Principles: With Applications to Core-Form Power Transformers, Second Edition remains focused on the basic physical concepts behind transformer design and operation. Starting with first principles, this book develops the reader's understanding of the rationale behind design practices by illustrating how basic formulae and modeling procedures are derived and used. Simplifies presentation and emphasizes fundamentals, making it easy to apply presented results to your own desi

  2. Latest achievements of CEA and AREVA NP on HTR fuel fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Charollais, Francois [CEA Cadarache, DEN/CAD/DEC/SPUA, Bat. 315, BP1, 13108 Saint Paul lez Durance (France)], E-mail: francois.charollais@cea.fr; Perrais, Christophe; Moulinier, Dominique [CEA Cadarache, DEN/CAD/DEC/SPUA, Bat. 315, BP1, 13108 Saint Paul lez Durance (France); Perez, Marc [CEA Grenoble, DRT/GRE/DTEN/S3ME, 17 rue des Martyrs, 38054 Grenoble Cedex 9 (France); Vitali, Marie-Pierre [CERCA, BP 1114, 26104 Romans sur Isere Cedex (France)

    2008-11-15

    Extensive research and development programs on the (Very) High Temperature gas cooled Reactor (V/HTR) are being conducted by many countries mainly promoted by the attractiveness of this concept and its capability for other applications than electricity production, such as high temperature process heat and cogeneration. In this international context, the Commissariat a l'Energie Atomique (CEA) and AREVA NP through its project called ANTARES (Areva New Technology for Advanced Reactor Energy Supply) conduct a V/HTR fuel development and qualification program, among which one major activity is dedicated to the mastering of the nuclear fuel fabrication technology. The fuel concept selected for this project is the compact design based on UO{sub 2} kernels and SiC coating. First laboratory-scale experiments were performed to recover the know-how of HTR-coated particles and fuel element manufacturing. The different stages of UO{sub 2} kernel fabrication by the Gel Supported Precipitation (GSP) process were reviewed and improved. Experimental conditions for the Chemical Vapour Deposition (CVD) of coatings have been defined on dummy kernels supported by a modelling approach of the CVD process. The compacting processes formerly used at CERCA were reviewed and updated. In order to support a future industrial manufacturing factory and to meet the next short-term challenge, which is the fabrication of coated particle batches that will be compacted for the first irradiation test scheduled in OSIRIS, a lab-scale experimental manufacturing facility, named CAPRI (CEA and AREVA PRoduction Integrated) line has been set up and is in operation since early 2005. The CAPRI line is composed of a manufacturing line for TRISO particles, named GAIA, located at CEA Cadarache, and a compacting line for fuel elements based at CERCA, AREVA NP Subsidiary, Romans. Since early 2005, many tests have been performed leading to a better understanding and optimization of coating particle and compact

  3. The Design and Performance of IceCube DeepCore

    Science.gov (United States)

    Stamatikos, M.

    2012-01-01

    The IceCube neutrino observatory in operation at the South Pole, Antarctica, comprises three distinct components: a large buried array for ultrahigh energy neutrino detection, a surface air shower array, and a new buried component called DeepCore. DeepCore was designed to lower the IceCube neutrino energy threshold by over an order of magnitude, to energies as low as about 10 GeV. DeepCore is situated primarily 2100 m below the surface of the icecap at the South Pole, at the bottom center of the existing IceCube array, and began taking pbysics data in May 2010. Its location takes advantage of the exceptionally clear ice at those depths and allows it to use the surrounding IceCube detector as a highly efficient active veto against the principal background of downward-going muons produced in cosmic-ray air showers. DeepCore has a module density roughly five times higher than that of the standard IceCube array, and uses photomultiplier tubes with a new photocathode featuring a quantum efficiency about 35% higher than standard IceCube PMTs. Taken together, these features of DeepCore will increase IceCube's sensitivity to neutrinos from WIMP dark matter annihilations, atmospheric neutrino oscillations, galactic supernova neutrinos, and point sources of neutrinos in the northern and southern skies. In this paper we describe the design and initial performance of DeepCore.

  4. Computational Design of Core/Shell Nanoparticles for Oxygen Reduction Reactions.

    Science.gov (United States)

    Zhang, Xu; Lu, Gang

    2014-01-16

    A computational strategy to design core/shell nanoparticle catalysts for oxygen reduction reactions (ORRs) is proposed based on multiscale modeling. Using a quantum mechanics/molecular mechanics (QM/MM) coupling method, we have studied the ORR on Pt-Cu core/shell nanoparticles with the size ranging from 3 to 8 nm. We have calculated the oxygen adsorption energy on the nanoparticle surface (a descriptor for ORR activity) as a function of the nanoparticle size and thickness of the Pt shell. We find that the Pt-Cu core/shell nanoparticles exhibit higher ORR activities than flat Pt(111) surfaces, consistent with experimental observations. We predict that the diameter of the core/shell nanoparticles should be larger than 7 nm to reach the peak of ORR activities. By examining the effects of ligand, quantum confinement, and surface strain, we confirm that the strain plays the dominant role on ORR activities for the core/shell nanoparticles. A universal relation between the surface strain and the oxygen adsorption energy is established based on which one can computationally screen and design core/shell nanoparticle catalysts for superior ORR activities.

  5. Design and analysis of large-core single-mode windmill single crystal sapphire optical fiber

    Science.gov (United States)

    Cheng, Yujie; Hill, Cary; Liu, Bo; Yu, Zhihao; Xuan, Haifeng; Homa, Daniel; Wang, Anbo; Pickrell, Gary

    2016-06-01

    We present a large-core single-mode "windmill" single crystal sapphire optical fiber (SCSF) design, which exhibits single-mode operation by stripping off the higher-order modes (HOMs) while maintaining the fundamental mode. The "windmill" SCSF design was analyzed using the finite element analysis method, in which all the HOMs are leaky. The numerical simulation results show single-mode operation in the spectral range from 0.4 to 2 μm in the windmill SCSF, with an effective core diameter as large as 14 μm. Such fiber is expected to improve the performance of many of the current sapphire fiber optic sensor structures.

  6. Research advances in polymer emulsion based on "core-shell" structure particle design.

    Science.gov (United States)

    Ma, Jian-zhong; Liu, Yi-hong; Bao, Yan; Liu, Jun-li; Zhang, Jing

    2013-09-01

    In recent years, quite many studies on polymer emulsions with unique core-shell structure have emerged at the frontier between material chemistry and many other fields because of their singular morphology, properties and wide range of potential applications. Organic substance as a coating material onto either inorganic or organic internal core materials promises an unparalleled opportunity for enhancement of final functions through rational designs. This contribution provides a brief overview of recent progress in the synthesis, characterization, and applications of both inorganic-organic and organic-organic polymer emulsions with core-shell structure. In addition, future research trends in polymer composites with core-shell structure are also discussed in this review. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Alternative system design concepts for the ITER core CXRS upper port plug front end

    Energy Technology Data Exchange (ETDEWEB)

    Krimmer, A., E-mail: A.Krimmer@fz-juelich.de [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Klinkhamer, F. [TNO Science and Industry, partner in ITER-NL, P.O. Box 155, 2600 AD Delft (Netherlands); Biel, W. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Hawkes, N. [Association EURATOM/CCFE, OX14 3DB, Abingdon (United Kingdom); Kiss, G. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Koning, J.F. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster and ITER-NL, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Krasikov, Yu.; Neubauer, O. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany)

    2011-10-15

    Highlights: > System design for the core CXRS diagnostic port plug for ITER is investigated. > Dependencies of the sub-systems are given. > Overall system lifetime and recent mechanical changes are taken into account. > System configurations are derived for the current ITER design. - Abstract: The upper port no. 3 in ITER will be used by the core Charge Exchange Recombination Spectroscopy (core CXRS) to channel out light from the inside of the vacuum vessel. Recent research about the lifetime of the first two mirrors and changes in the upper port plug geometry initiated further investigations into possible alternative system design concepts. Two new variants of the optical system were chosen for further investigation. The different sub-systems of core CXRS such as optical system, retractable tube and shutter are introduced together with their impact on the system design and their interactions. Space constraints originating from the envelope of the UPP and requirements emerging from the ITER environment such as remote handling and other maintenance considerations are also included in the investigation. Alternative system concepts taking the constraints into account are presented and discussed. Implications for further design work on the subsystems are derived from the results.

  8. Proteomics Core

    Data.gov (United States)

    Federal Laboratory Consortium — Proteomics Core is the central resource for mass spectrometry based proteomics within the NHLBI. The Core staff help collaborators design proteomics experiments in a...

  9. Quantitative Homogeneity and In-Contact Particles of High Temperature Reactors (htr) Compacts Determination via X-Ray Tomography

    Science.gov (United States)

    Lecomte, G.; Tisseur, D.; Létang, J. M.; Banchet, J.; Vitali, M. P.

    2008-02-01

    In AREVA Nuclear Power's High Temperature Reactor (HTR) design called ANTARES, fuel consists of compacts composed of few thousands millimetric quasi-spherical particles dispersed in a graphite matrix. Compact homogeneity, defined as the homogeneous particles spatial distribution in the matrix, as well as the possibility of obtaining particles in contact, need to be assessed since they condition the thermo-mechanical behavior of the nuclear fuel under irradiation. In this paper, image and data processing algorithms are developed to do so, based on X-Ray tomographic images.

  10. CopperCore: a service based approach towards implementing the IMS Learning Design specification.

    NARCIS (Netherlands)

    Vogten, Hubert

    2006-01-01

    This paper presents a service developed by the Open University of the Netherlands, called CopperCore which implements an IMS Learning Design engine as service. The overall architecture is described including a detailed description of the web service application programming interfaces.

  11. LAVENDER: A steady-state core analysis code for design studies of accelerator driven subcritical reactors

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Shengcheng; Wu, Hongchun; Cao, Liangzhi; Zheng, Youqi, E-mail: yqzheng@mail.xjtu.edu.cn; Huang, Kai; He, Mingtao; Li, Xunzhao

    2014-10-15

    Highlights: • A new code system for design studies of accelerator driven subcritical reactors (ADSRs) is developed. • S{sub N} transport solver in triangular-z meshes, fine deletion analysis and multi-channel thermal-hydraulics analysis are coupled in the code. • Numerical results indicate that the code is reliable and efficient for design studies of ADSRs. - Abstract: Accelerator driven subcritical reactors (ADSRs) have been proposed and widely investigated for the transmutation of transuranics (TRUs). ADSRs have several special characteristics, such as the subcritical core driven by spallation neutrons, anisotropic neutron flux distribution and complex geometry etc. These bring up requirements for development or extension of analysis codes to perform design studies. A code system named LAVENDER has been developed in this paper. It couples the modules for spallation target simulation and subcritical core analysis. The neutron transport-depletion calculation scheme is used based on the homogenized cross section from assembly calculations. A three-dimensional S{sub N} nodal transport code based on triangular-z meshes is employed and a multi-channel thermal-hydraulics analysis model is integrated. In the depletion calculation, the evolution of isotopic composition in the core is evaluated using the transmutation trajectory analysis algorithm (TTA) and fine depletion chains. The new code is verified by several benchmarks and code-to-code comparisons. Numerical results indicate that LAVENDER is reliable and efficient to be applied for the steady-state analysis and reactor core design of ADSRs.

  12. Design of homogeneous trench-assisted multi-core fibers based on analytical model

    DEFF Research Database (Denmark)

    Ye, Feihong; Tu, Jiajing; Saitoh, Kunimasa

    2016-01-01

    We present a design method of homogeneous trench-assisted multicore fibers (TA-MCFs) based on an analytical model utilizing an analytical expression for the mode coupling coefficient between two adjacent cores. The analytical model can also be used for crosstalk (XT) properties analysis, such as ...

  13. Optimized core design and fuel management of a pebble-bed type nuclear reactor

    NARCIS (Netherlands)

    Boer, B.

    2009-01-01

    The core design of a pebble-bed type Very High Temperature Reactor (VHTR) is optimized, aiming for an increase of the coolant outlet temperature to 1000 C, while retaining its inherent safety features. The VHTR has been selected by the international Generation IV research initiative as one of the

  14. Different contributions of HtrA protease and chaperone activities to Campylobacter jejuni stress tolerance and physiology

    DEFF Research Database (Denmark)

    Bæk, Kristoffer Torbjørn; Vegge, Christina Skovgaard; Skórko-Glonek, Joanna

    2011-01-01

    activity is sufficient for growth at high temperature or oxidative stress, whereas the HtrA protease activity is only essential at conditions close to the growth limit for C. jejuni. However, the protease activity was required to prevent induction of the cytoplasmic heat-shock response even at optimal......, but little is known about how each of these activities contributes to stress tolerance in bacteria. In vitro experiments showed temperature dependent protease and chaperone activities of C. jejuni HtrA. A C. jejuni mutant lacking only the protease activity of HtrA was used to show that the HtrA chaperone...... growth conditions. Interestingly, the requirement of HtrA at high temperatures was found to depend on the oxygen level and our data suggest that HtrA may protect oxidatively damaged proteins. Finally, protease activity stimulates HtrA production and oligomer formation, suggesting that a regulatory role...

  15. Design of a family of ring-core fibers for OAM transmission studies.

    Science.gov (United States)

    Brunet, Charles; Ung, Bora; Wang, Lixian; Messaddeq, Younès; LaRochelle, Sophie; Rusch, Leslie A

    2015-04-20

    We propose a family of ring-core fibers, designed for the transmission of OAM modes, that can be fabricated by drawing five different fibers from a single preform. This novel technique allows us to experimentally sweep design parameters and speed up the fiber design optimization process. Such a family of fibers could be used to examine system performance, but also facilitate understanding of parameter impact in the transition from design to fabrication. We present design parameters characterizing our fiber, and enumerate criteria to be satisfied. We determine targeted fiber dimensions and explain our strategy for examining a design family rather than a single fiber design. We simulate modal properties of the designed fibers, and compare the results with measurements performed on fabricated fibers.

  16. Overview on R&D and design activities for the ITER core charge exchange spectroscopy diagnostic system

    NARCIS (Netherlands)

    Biel, W.; Baross, T.; Bourauel, P.; Dunai, D.; Durkut, M.; Erdei, G.; Hawkes, N.; Hellermann, M. von; Hogenbirk, A.; Jaspers, R.; Kiss, G.; Klinkhamer, J.F.F.; Koning, J.F.; Kotov, V.; Krasikov, Y.; Krimmer, A.; Lischtschenko, O.; Litnovsky, A.; Marchuk, O.; Neubauer, O.; Offermanns, G.; Panin, A.; Patel, K.; Pokol, G.; Schrader, M.; Snijders, B.; Szabo, V.; Valk, N.J.C. van der; Voinchet, R.; Wolters, J.; Zoletnik, S.

    2011-01-01

    The ITER core charge exchange recombination spectroscopy (core CXRS) diagnostic system is designed to provide experimental access to various measurement quantities in the ITER core plasma such as ion densities, temperatures and velocities. The implementation of the approved CXRS diagnostic principle

  17. Design of a supercritical water-cooled reactor with a three-pass core arrangement

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K. [EnBW Kernkraft GmbH, Kernkraftwerk Philippsburg, D-76661 Philippsburg (Germany)], E-mail: kai-fischer@gmx.de; Schulenberg, T. [Forschungszentrum Karlsruhe GmbH, Institute for Nuclear and Energy Technologies, P.O. Box 3640, D-76021 Karlsruhe (Germany); Laurien, E. [University of Stuttgart, Institute for Nuclear and Energy Systems (IKE), Pfaffenwaldring 31, D-70569 Stuttgart (Germany)

    2009-04-15

    The Supercritical Water-cooled Reactor (SCWR) is one of the six concepts of the Generation IV International Forum. In Europe, investigations have been integrated into a joint research project, called High Performance Light Water Reactor (HPLWR). Due to the higher heat up within the core and a higher outlet temperature, a significant increase in turbine power and thermal efficiency of the plant can be expected. Besides the higher pressure and higher steam temperature, the design concept of this type of reactor differs significantly from a conventional LWR by a different core concept. In order to achieve the high outlet temperature of over 500 deg. C, a core with a three-step heat up and intermediate mixing is proposed to keep local cladding temperatures within today's material limits. A design for the reactor pressure vessel (RPV) and the internals has been worked out to incorporate a core arrangement with three passes. All components have been dimensioned following the safety standards of the nuclear safety standards commission in Germany. Additionally, a fuel assembly cluster with head and foot piece has been developed to facilitate the complex flow path for the multi-pass concept. The design of the internals and of the RPV is verified using mechanical or, in the case of large thermal deformations, combined mechanical and thermal stress analyses. Furthermore, the reactor design ensures that the total coolant flow path remains closed against leakage of colder moderator water even in case of large thermal expansions of the components. The design of the RPV and internals is now available for detailed analyses of the core and the reactor.

  18. New Small LWR Core Designs using Particle Burnable Poisons for Low Boron Concentration

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Ho Seong; Hwang, Dae Hee; Hong, Ser Gi [Kyung Hee University, Yongin (Korea, Republic of)

    2015-05-15

    The soluble boron has two major important roles in commercial PWR operations : 1) the control of the long-term reactivity to maintain criticality under normal operation, and 2) the shutdown of the reactor under accidents. However, the removal of the soluble boron gives several advantages in SMRs (Small Modular Reactor). These advantages resulted from the elimination of soluble boron include the significant simplification of nuclear power plant through the removal of pipes, pumps, and purification systems. Also, the use of soluble boron mitigates corrosion problems on the primary coolant loop. Furthermore, the soluble boron-free operation can remove an inadvertent boron dilution accident (BDA) which can lead to a significant insertion of positive reactivity. From the viewpoint of core physics, the removal of soluble boron or reduction of soluble boron concentration makes the moderator temperature coefficient (MTC) more negative. From the core design studies using new fuel assemblies, it is shown that the cores have very low critical soluble boron concentrations less than 500ppm, low peaking factors within the design targets, strong negative MTCs over cycles, and large enough shutdown margins both at BOC and EOC. However, the present cores have relatively low average discharge burnups of ∼ 30MWD/kg leading to low fuel economy because the cores use lots of non-fuel burnable poison rods to achieve very low critical boron concentrations. So, in the future, we will perform the trade-off study between the fuel discharge burnup and the boron concentrations by changing fuel assembly design and the core loading pattern.

  19. Comparison of Calculated value by the Core Design ASTRA Code with Measured Data

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Ji Eun; Yang, Sung Tae [Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

    2012-05-15

    ASTRA is a unique proprietary core design code being developed by KEPCO NF. This code is still under development, but it can nonetheless be analyzed and given feedback by a utility. This study will be used to develop a risk assessment procedure based on the ASTRA code. The calculated values of the ASTRA code and the measurement values are compared here using the data for Cycle 12 of Younggwang Nuclear Unit 3. The reactor core is composed of 177 fuel assemblies, consisting of a 16x16 array with 236 fuel rods and 5 guide tubes

  20. High-Order Homogenization Method in Diffusion Theory for Reactor Core Simulation and Design Calculation

    Energy Technology Data Exchange (ETDEWEB)

    Farzad Rahnema

    2003-09-30

    Most modern nodal methods in use by the reactor vendors and utilities are based on the generalized equivalence theory (GET) that uses homogenized cross sections and flux discontinuity factors. These homogenized parameters, referred to as infinite medium parameters, are precomputed by performing single bundle fine-mesh calculations with zero current boundary conditions. It is known that for configurations in which the node-to-node leakage (e.g., surface current-to-flux ratio) is large the use of the infinite medium parameters could lead to large errors in the nodal solution. This would be the case for highly heterogeneous core configurations, typical of modern reactor core designs.

  1. The nucleus accumbens 5-HTR4-CART pathway ties anorexia to hyperactivity

    Science.gov (United States)

    Jean, A; Laurent, L; Bockaert, J; Charnay, Y; Dusticier, N; Nieoullon, A; Barrot, M; Neve, R; Compan, V

    2012-01-01

    In mental diseases, the brain does not systematically adjust motor activity to feeding. Probably, the most outlined example is the association between hyperactivity and anorexia in Anorexia nervosa. The neural underpinnings of this ‘paradox', however, are poorly elucidated. Although anorexia and hyperactivity prevail over self-preservation, both symptoms rarely exist independently, suggesting commonalities in neural pathways, most likely in the reward system. We previously discovered an addictive molecular facet of anorexia, involving production, in the nucleus accumbens (NAc), of the same transcripts stimulated in response to cocaine and amphetamine (CART) upon stimulation of the 5-HT4 receptors (5-HTR4) or MDMA (ecstasy). Here, we tested whether this pathway predisposes not only to anorexia but also to hyperactivity. Following food restriction, mice are expected to overeat. However, selecting hyperactive and addiction-related animal models, we observed that mice lacking 5-HTR1B self-imposed food restriction after deprivation and still displayed anorexia and hyperactivity after ecstasy. Decryption of the mechanisms showed a gain-of-function of 5-HTR4 in the absence of 5-HTR1B, associated with CART surplus in the NAc and not in other brain areas. NAc-5-HTR4 overexpression upregulated NAc-CART, provoked anorexia and hyperactivity. NAc-5-HTR4 knockdown or blockade reduced ecstasy-induced hyperactivity. Finally, NAc-CART knockdown suppressed hyperactivity upon stimulation of the NAc-5-HTR4. Additionally, inactivating NAc-5-HTR4 suppressed ecstasy's preference, strengthening the rewarding facet of anorexia. In conclusion, the NAc-5-HTR4/CART pathway establishes a ‘tight-junction' between anorexia and hyperactivity, suggesting the existence of a primary functional unit susceptible to limit overeating associated with resting following homeostasis rules. PMID:23233022

  2. Embedded memory design for multi-core and systems on chip

    CERN Document Server

    Mohammad, Baker

    2014-01-01

    This book describes the various tradeoffs systems designers face when designing embedded memory.  Readers designing multi-core systems and systems on chip will benefit from the discussion of different topics from memory architecture, array organization, circuit design techniques and design for test.  The presentation enables a multi-disciplinary approach to chip design, which bridges the gap between the architecture level and circuit level, in order to address yield, reliability and power-related issues for embedded memory.  ·         Provides a comprehensive overview of embedded memory design and associated challenges and choices; ·         Explains tradeoffs and dependencies across different disciplines involved with multi-core and system on chip memory design; ·         Includes detailed discussion of memory hierarchy and its impact on energy and performance; ·         Uses real product examples to demonstrate embedded memory design flow from architecture, to circuit ...

  3. A validation report for the KALIMER core design computing system by the Monte Carlo transport theory code

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ki Bog; Kim, Yeong Il; Kim, Kang Seok; Kim, Sang Ji; Kim, Young Gyun; Song, Hoon; Lee, Dong Uk; Lee, Byoung Oon; Jang, Jin Wook; Lim, Hyun Jin; Kim, Hak Sung

    2004-05-01

    In this report, the results of KALIMER (Korea Advanced LIquid MEtal Reactor) core design calculated by the K-CORE computing system are compared and analyzed with those of MCDEP calculation. The effective multiplication factor, flux distribution, fission power distribution and the number densities of the important nuclides effected from the depletion calculation for the R-Z model and Hex-Z model of KALIMER core are compared. It is confirmed that the results of K-CORE system compared with those of MCDEP based on the Monte Carlo transport theory method agree well within 700 pcm for the effective multiplication factor estimation and also within 2% in the driver fuel region, within 10% in the radial blanket region for the reaction rate and the fission power density. Thus, the K-CORE system for the core design of KALIMER by treating the lumped fission product and mainly important nuclides can be used as a core design tool keeping the necessary accuracy.

  4. A Small Modular Reactor Core Design using FCM Fuel and BISO BP particles

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae Yeon; Hwang, Dae Hee; Yoo, Ho Seong; Hong, Ser Gi [Kyung Hee University, Yongin (Korea, Republic of)

    2016-10-15

    The objective of this work is to design a PWR small modular reactor which employs the advanced fuel technology of FCM particle fuels including BISO burnable poisons and advanced cladding of SiC in order to improve the fuel economy and safety by increasing fuel burnup and temperature, and by reducing hydrogen generation under accidents. Recently, many countries including USA have launched projects to develop the accident tolerant fuels (ATF) which can cope with the accidents such as LOCA (Loss of Coolant Accident). In general, the ATF fuels are required to meet the PWR operational, safety, and fuel cycle constraints which include enhanced burnup, lower or no generation of hydrogen, lower operating temperatures, and enhanced retention of fission products. Another stream of research and development in nuclear society is to develop advanced small modular reactors in order to improve inherent passive safety and to reduce the risk of large capital investment. In this work, a small PWR modular reactor core was neutronically designed and analyzed. The SMR core employs new 13x13 fuel assemblies which are loaded with thick FCM fuel rods in which TRISO fuel particles AO and also the first cycle has the AOs which are within the typical design limit. Also, this figure shows that the evolutions of AO for the cycles 6 and 7 are nearly the same. we considered the SiC cladding for reduction of hydrogen generation under accidents. From the results of core design and analysis, it is shown that the core has long cycle length of 732 -1191 EFPDs, high discharge burnup of 101-105 MWD/kg, low power peaking factors, low axial offsets, negative MTCs, and large shutdown margins except for BOC of the first cycle. So, it can be concluded that the new SMR core is neutronically feasible.

  5. Experimental and numerical investigation of the flow measurement method utilized in the steam generator of HTR-PM

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Shiming; Ren, Cheng; Sun, Yangfei [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); Tu, Jiyuan [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China); School of Aerospace, Mechanical & Manufacturing Engineering, RMIT University, Melbourne, VIC 3083 (Australia); Yang, Xingtuan, E-mail: yangxt107@sina.com [Institute of Nuclear and New Energy Technology of Tsinghua University, Collaborative Innovation Center of Advanced Nuclear Energy Technology, Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of Education, Beijing 100084 (China)

    2016-08-15

    Highlights: • The flow confluence process in the steam generator is very important for HTR-PM. • The complicated flow in the unique pipeline configuration is studied by both of experimental and numerical method. • The pressure uniformity at the bottom of the model was tested to evaluate the accuracy of the experimental results. • Flow separation and the secondary flow is described for explaining the nonuniformity of the flow distribution. - Abstract: The helium flow measurement method is very important for the design of HTR-PM. Water experiments and numerical simulation with a 1/5 scaled model are conducted to investigate the flow measurement method utilized in the steam generator of HTR-PM. Pressure information at specific location of the 90° elbows with the diameter of 46.75 mm and radius ratio of 1.5 is measured to evaluate the flow rate in the riser-pipes. Pressure uniformity at the bottom of the experimental apparatus is tested to evaluate the influence of the equipment error on the final experimental results. Numerical results obtained by using the realizable k–ε model are compared with the experimental data. The results reveal that flow oscillation does not occur in the confluence system. For every single riser-pipe, the flow is stable despite the nonuniformity of the flow distribution. The average flow rates of the two pipe series show good repeatability regardless of the increases and decreases of the average velocity. In the header box, the flows out of the riser-pipes encounter with each other and finally distort the pressure distribution and the nonuniformity of the flow distribution becomes more significant along with the increasing Reynolds number.

  6. In-situ hybridization based quantification of hTR: a possible biomarker in malignant melanoma

    DEFF Research Database (Denmark)

    Vagner, Josephine; Steiniche, Torben; Stougaard, Magnus

    2015-01-01

    Aims Telomerase is reactivated in most cancers and there is accumulating evidence for it being a driver event in malignant melanoma (MM). Thus, our aim was to evaluate if in situ hybridisation (ISH)-based quantification of the telomerase RNA (hTR) could be used to distinguish MM from nevi...... thickness suggesting that hTR might be a valuable biomarker in MM. Furthermore, as ISH-based detection requires presence of both hTR and the reverse transcriptase (hTERT) it might be an indicator of active telomerase and thus have future relevance as a predictive biomarker for anti-telomerase treatment....

  7. Design and numerical analysis of microstructured-core octagonal photonic crystal fiber for sensing applications

    Directory of Open Access Journals (Sweden)

    Kawsar Ahmed

    2016-03-01

    Full Text Available This paper presents an octagonal photonic crystal fiber (O-PCF for liquid sensing, in which both core and cladding are microstructured. Some propagation characteristics of proposed structure have been investigated by using the full vectorial finite element method (FEM. Confinement loss and sensitivity are examined and compared with varying number of rings, core diameter, diameter of air holes in cladding ring and pitch. It is found that sensitivity is increased for the increment pitch value, air filling ratio, core diameter, inner ring diameter as well as number of rings. At the same time confinement loss is significantly decreased. It is also found that the increment of pitch by keeping the same air filling ratio increases the sensitivity and loss. Investigating the effects of different parameters, an O-PCF structure is designed which has a significantly higher relative sensitivity and lower confinement loss.

  8. Design and intestinal mucus penetration mechanism of core-shell nanocomplex.

    Science.gov (United States)

    Zhang, Xin; Cheng, Hongbo; Dong, Wei; Zhang, Meixia; Liu, Qiaoyu; Wang, Xiuhua; Guan, Jian; Wu, Haiyang; Mao, Shirui

    2018-02-28

    The objective of this study was to design intestinal mucus-penetrating core-shell nanocomplex by functionally mimicking the surface of virus, which can be used as the carrier for peroral delivery of macromolecules, and further understand the influence of nanocomplex surface properties on the mucosal permeation capacity. Taking insulin as a model drug, the core was formed by the self-assembly among positively charged chitosan, insulin and negatively charged sodium tripolyphosphate, different types of alginates were used as the shell forming material. The nanocomplex was characterized by dynamic light scattering (DLS), atomic force microscopy (AFM) and FTIR. Nanocomplex movement in mucus was recorded using multiple particle tracking (MPT) method. Permeation and uptake of different nanocomplex were studied in rat intestine. It was demonstrated that alginate coating layer was successfully formed on the core and the core-shell nanocomplex showed a good physical stability and improved enzymatic degradation protection. The mucus penetration and MPT study showed that the mucus penetration capacity of the nanocomplex was surface charge and coating polymer structure dependent, nanocomplex with negative alginate coating had 1.6-2.5 times higher mucus penetration ability than that of positively charged chitosan-insulin nanocomplex. Moreover, the mucus penetration ability of the core-shell nanocomplex was alginate structure dependent, whereas alginate with lower G content and lower molecular weight showed the best permeation enhancing ability. The improvement of intestine permeation and intestinal villi uptake of the core-shell nanocomplex were further confirmed in rat intestine and multiple uptake mechanisms were involved in the transport process. In conclusion, core-shell nanocomplex composed of oppositely charged materials could provide a strategy to overcome the mucus barrier and enhance the mucosal permeability. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. First principles design of a core bioenergetic transmembrane electron transfer protein

    Science.gov (United States)

    Goparaju, Geetha; Fry, Bryan A.; Chobot, Sarah E.; Wiedman, Gregory; Moser, Christopher C.; Dutton, P. Leslie; Discher, Bohdana M.

    2016-01-01

    Here we describe the design, E. coli expression and characterization of a simplified, adaptable and functionally transparent single chain 4-α-helix transmembrane protein frame that binds multiple heme and light activatable porphyrins. Such man-made cofactor-binding oxidoreductases, designed from first principles with minimal reference to natural protein sequences, are known as maquettes. This design is an adaptable frame aiming to uncover core engineering principles governing bioenergetic transmembrane electron-transfer function and recapitulate protein archetypes proposed to represent the origins of photosynthesis. PMID:26672896

  10. A comparison of designer activity using core design situations in the laboratory and practice

    DEFF Research Database (Denmark)

    Cash, Philip; Hicks, Ben J.; Culley, Steve J.

    2013-01-01

    In 2011 one quarter of all articles published in Design Studies and the Journal of Engineering Design used experimental studies. However, there is little work exploring the relationship between laboratory and practice. This paper addresses this by detailing an analysis of designer activity in three...

  11. Advanced Core Design And Fuel Management For Pebble-Bed Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Hans D. Gougar; Abderrafi M. Ougouag; William K. Terry

    2004-10-01

    A method for designing and optimizing recirculating pebble-bed reactor cores is presented. At the heart of the method is a new reactor physics computer code, PEBBED, which accurately and efficiently computes the neutronic and material properties of the asymptotic (equilibrium) fuel cycle. This core state is shown to be unique for a given core geometry, power level, discharge burnup, and fuel circulation policy. Fuel circulation in the pebble-bed can be described in terms of a few well?defined parameters and expressed as a recirculation matrix. The implementation of a few heat?transfer relations suitable for high-temperature gas-cooled reactors allows for the rapid estimation of thermal properties critical for safe operation. Thus, modeling and design optimization of a given pebble-bed core can be performed quickly and efficiently via the manipulation of a limited number key parameters. Automation of the optimization process is achieved by manipulation of these parameters using a genetic algorithm. The end result is an economical, passively safe, proliferation-resistant nuclear power plant.

  12. Insert Design and Manufacturing for Foam-Core Composite Sandwich Structures

    Science.gov (United States)

    Lares, Alan

    Sandwich structures have been used in the aerospace industry for many years. The high strength to weight ratios that are possible with sandwich constructions makes them desirable for airframe applications. While sandwich structures are effective at handling distributed loads such as aerodynamic forces, they are prone to damage from concentrated loads at joints or due to impact. This is due to the relatively thin face-sheets and soft core materials typically found in sandwich structures. Carleton University's Uninhabited Aerial Vehicle (UAV) Project Team has designed and manufactured a UAV (GeoSury II Prototype) which features an all composite sandwich structure fuselage structure. The purpose of the aircraft is to conduct geomagnetic surveys. The GeoSury II Prototype serves as the test bed for many areas of research in advancing UAV technologies. Those areas of research include: low cost composite materials manufacturing, geomagnetic data acquisition, obstacle detection, autonomous operations and magnetic signature control. In this thesis work a methodology for designing and manufacturing inserts for foam-core sandwich structures was developed. The results of this research work enables a designer wishing to design a foam-core sandwich airframe structure, a means of quickly manufacturing optimized inserts for the safe introduction of discrete loads into the airframe. The previous GeoSury II Prototype insert designs (v.1 & v.2) were performance tested to establish a benchmark with which to compare future insert designs. Several designs and materials were considered for the new v.3 inserts. A plug and sleeve design was selected, due to its ability to effectively transfer the required loads to the sandwich structure. The insert material was chosen to be epoxy, reinforced with chopped carbon fibre. This material was chosen for its combination of strength, low mass and also compatibility with the face-sheet material. The v.3 insert assembly is 60% lighter than the

  13. Evaluation of Borrelia burgdorferi BbHtrA Protease as a Vaccine Candidate for Lyme Borreliosis in Mice.

    Directory of Open Access Journals (Sweden)

    Amy J Ullmann

    Full Text Available Borrelia burgdorferi synthesizes an HtrA protease (BbHtrA which is a surface-exposed, conserved protein within Lyme disease spirochetes with activity toward CheX and BmpD of Borrelia spp, as well as aggrecan, fibronectin and proteoglycans found in skin, joints and neural tissues of vertebrates. An antibody response against BbHtrA is observed in Lyme disease patients and in experimentally infected laboratory mice and rabbits. Given the surface location of BbHtrA on B. burgdorferi and its ability to elicit an antibody response in infected hosts, we explored recombinant BbHtrA as a potential vaccine candidate in a mouse model of tick-transmitted Lyme disease. We immunized mice with two forms of BbHtrA: the proteolytically active native form and BbHtrA ablated of activity by a serine to alanine mutation at amino acid 226 (BbHtrA(S226A. Although inoculation with either BbHtrA or BbHtrA(S226A produced high-titer antibody responses in C3H/HeJ mice, neither antigen was successful in protecting mice from B. burgdorferi challenge. These results indicate that the search for novel vaccine candidates against Lyme borreliosis remains a challenge.

  14. RELAP5 model for advanced neutron source reactor thermal-hydraulic transients, three-element-core design

    Energy Technology Data Exchange (ETDEWEB)

    Chen, N.C.J.; Wendel, M.W.; Yoder, G.L.

    1996-02-01

    In order to utilize reduced enrichment fuel, the three-element-core design has been proposed. The proposed core configuration consists of inner, middle, and outer elements, with the middle element offset axially beneath the inner and outer elements, which are axially aligned. The three-element-core RELAP5 model assumes that the reactor hardware is changed only within the core region, so that the loop piping, heat exchangers, and pumps remain as assumed for the two-element-core configuration. However, the total flow rate through the core is greater and the pressure drop across the core is less so that the primary coolant pumps and heat exchangers are operating at a different point in their performance curves. This report describes the new RELAP5 input for the core components.

  15. Hardware-Software Co-design of QRD-RLS Algorithm with Microblaze Soft Core Processor

    Science.gov (United States)

    Lodha, Nupur; Rai, Nivesh; Dubey, Rahul; Venkataraman, Hrishikesh

    This paper presents the implementation of QR Decomposition based Recursive Least Square (QRD-RLS) algorithm on Field Programmable Gate Arrays (FPGA). The design is based on hardware-software co-design. The hardware part consists of a custom peripheral that solves the part of the algorithm with higher computational costs and the software part consists of an embedded soft core processor that manages the control functions and rest of the algorithm. The use of Givens Rotation and Systolic Arrays make this architecture suitable for FPGA implementation. Moreover, the speed and flexibility of FPGAs render them viable for such computationally intensive application. The system has been implemented on Xilinx Spartan 3E FPGA with Microblaze soft core processor using Embedded Development Kit (EDK). The paper also presents the implementation results and their analysis.

  16. Optimum design of imploded core plasma for effective fast ignition at GXII

    Directory of Open Access Journals (Sweden)

    Nagatomo H.

    2013-11-01

    Full Text Available In the implosion phase of the fast ignition scheme, most critical issues are breakup of the cone tip and the formation of high ρ-R core plasma to improve its heating efficiency. For the integrated fast ignition experiment at ILE Osaka University, robust and reliable implosion must be redesign. In this paper, feasible target design under the constraint condition of existing GXII and LFEX facilities is studied using two-dimensional radiation hydrodynamic simulations, and an optimum target design based on low velocity implosion is proposed. The advantages of low velocity implosion are low adiabat, robust against Rayleigh-Taylor instability, which are verified. Also longer life time of compressed core plasma which is preferable for fast ignition is confirmed in this study.

  17. FEM 2D and 3D design of transformer for core losses computation

    OpenAIRE

    Sarac, Vasilija

    2017-01-01

    Accurate simulation and prediction of losses in power transformer is important during transformer lifetime but also during the design stage. Paper presents the simulation model of transformer based of Finite Element Method that allows calculation of core losses and magnetic flux density in transformer cross-section. Two different models are constructed for 2D and 3D simulation. Obtained results are compared with experiments. Finally, flux density in both models is calculated and obtained r...

  18. Design, synthesis and photochemical properties of the first examples of iminosugar clusters based on fluorescent cores

    Directory of Open Access Journals (Sweden)

    Mathieu L. Lepage

    2015-05-01

    Full Text Available The synthesis and photophysical properties of the first examples of iminosugar clusters based on a BODIPY or a pyrene core are reported. The tri- and tetravalent systems designed as molecular probes and synthesized by way of Cu(I-catalysed azide–alkyne cycloadditions are fluorescent analogues of potent pharmacological chaperones/correctors recently reported in the field of Gaucher disease and cystic fibrosis, two rare genetic diseases caused by protein misfolding.

  19. Comparative analysis of preliminary design core of TRIGA Bandung using fuel element plate MTR in Indonesia

    Science.gov (United States)

    Ramadhan, Anwar Ilmar; Umar, Efrizon; Tandian, Nathanael Panagung; Suwono, Aryadi

    2017-01-01

    TRIGA Bandung is a research nuclear reactor owned by Indonesia, located in Bandung with a power of 2 MWth. Nuclear research reactor TRIGA Bandung is used as a center for applied research and development in the field of application of the nuclear technologies. TRIGA Bandung is currently still using a cylindrical fuel element, this raises a new problem - the limited number of existing fuel element. The purpose of this research is the development of the preliminary core design of a nuclear research reactor TRIGA Bandung using fuel element plate MTR. The research method is modeling and simulation the preliminary design core of nuclear research reactor TRIGA Bandung using comparative method of porous media and non-porous media with CFD code. This research shows the velocity flow and temperature distribution and the influence of pressure from the comparison method of k-ɛ standard model and porous media model at the preliminary design in the core area of TRIGA Bandung research reactor with fuel element plate MTR.

  20. The novel role of HtrA1 in gingivitis, chronic and aggressive periodontitis.

    Science.gov (United States)

    Lorenzi, Teresa; Niţulescu, Elena Annabel; Zizzi, Antonio; Lorenzi, Maria; Paolinelli, Francesca; Aspriello, Simone Domenico; Baniţă, Monica; Crăiţoiu, Stefania; Goteri, Gaia; Barbatelli, Giorgio; Lombardi, Tommaso; Di Felice, Roberto; Marzioni, Daniela; Rubini, Corrado; Castellucci, Mario

    2014-01-01

    Proteolytic tissue degradation is a typical phenomenon in inflammatory periodontal diseases. HtrA1 (High temperature requirement A 1) has a serine protease activity and is able to degrade fibronectin whose fragments induce the expression and secretion of several matrix metalloproteinases (MMPs). The aim of this study was to investigate for the first time if HtrA1 has a role in gingivitis and in generalized forms of chronic and aggressive periodontitis. Expression of HtrA1 was investigated in 16 clinically healthy gingiva, 16 gingivitis, 14 generalized chronic periodontitis and 10 generalized aggressive periodontitis by immunohistochemistry and real-time PCR. Statistical comparisons were performed by the Kruskall-Wallis test. Significantly higher levels of HtrA1 mRNA and protein expression were observed in pathological respect to healthy tissues. In particular, we detected an increase of plasma cell HtrA1 immunostaining from gingivitis to chronic and aggressive periodontitis, with the higher intensity in aggressive disease. In addition, we observed the presence of HtrA1 in normal and pathological epithelium, with an increased expression, particularly in its superficial layer, associated with increasingly severe forms of periodontal disease. We can affirm that HtrA1 expression in plasma cells could be correlated with the destruction of pathological periodontal tissue, probably due to its ability to trigger the overproduction of MMPs and to increase the inflammatory mediators TNF-α and IL-1β by inhibition of TGF-β. Moreover, epithelial HtrA1 immunostaining suggests a participation of the molecule in the host inflammatory immune responses necessary for the control of periodontal infection.

  1. The novel role of HtrA1 in gingivitis, chronic and aggressive periodontitis.

    Directory of Open Access Journals (Sweden)

    Teresa Lorenzi

    Full Text Available Proteolytic tissue degradation is a typical phenomenon in inflammatory periodontal diseases. HtrA1 (High temperature requirement A 1 has a serine protease activity and is able to degrade fibronectin whose fragments induce the expression and secretion of several matrix metalloproteinases (MMPs. The aim of this study was to investigate for the first time if HtrA1 has a role in gingivitis and in generalized forms of chronic and aggressive periodontitis. Expression of HtrA1 was investigated in 16 clinically healthy gingiva, 16 gingivitis, 14 generalized chronic periodontitis and 10 generalized aggressive periodontitis by immunohistochemistry and real-time PCR. Statistical comparisons were performed by the Kruskall-Wallis test. Significantly higher levels of HtrA1 mRNA and protein expression were observed in pathological respect to healthy tissues. In particular, we detected an increase of plasma cell HtrA1 immunostaining from gingivitis to chronic and aggressive periodontitis, with the higher intensity in aggressive disease. In addition, we observed the presence of HtrA1 in normal and pathological epithelium, with an increased expression, particularly in its superficial layer, associated with increasingly severe forms of periodontal disease. We can affirm that HtrA1 expression in plasma cells could be correlated with the destruction of pathological periodontal tissue, probably due to its ability to trigger the overproduction of MMPs and to increase the inflammatory mediators TNF-α and IL-1β by inhibition of TGF-β. Moreover, epithelial HtrA1 immunostaining suggests a participation of the molecule in the host inflammatory immune responses necessary for the control of periodontal infection.

  2. The Novel Role of HtrA1 in Gingivitis, Chronic and Aggressive Periodontitis

    Science.gov (United States)

    Zizzi, Antonio; Lorenzi, Maria; Paolinelli, Francesca; Aspriello, Simone Domenico; Baniţă, Monica; Crăiţoiu, Ştefania; Goteri, Gaia; Barbatelli, Giorgio; Lombardi, Tommaso; Di Felice, Roberto; Marzioni, Daniela; Rubini, Corrado; Castellucci, Mario

    2014-01-01

    Proteolytic tissue degradation is a typical phenomenon in inflammatory periodontal diseases. HtrA1 (High temperature requirement A 1) has a serine protease activity and is able to degrade fibronectin whose fragments induce the expression and secretion of several matrix metalloproteinases (MMPs). The aim of this study was to investigate for the first time if HtrA1 has a role in gingivitis and in generalized forms of chronic and aggressive periodontitis. Expression of HtrA1 was investigated in 16 clinically healthy gingiva, 16 gingivitis, 14 generalized chronic periodontitis and 10 generalized aggressive periodontitis by immunohistochemistry and real-time PCR. Statistical comparisons were performed by the Kruskall-Wallis test. Significantly higher levels of HtrA1 mRNA and protein expression were observed in pathological respect to healthy tissues. In particular, we detected an increase of plasma cell HtrA1 immunostaining from gingivitis to chronic and aggressive periodontitis, with the higher intensity in aggressive disease. In addition, we observed the presence of HtrA1 in normal and pathological epithelium, with an increased expression, particularly in its superficial layer, associated with increasingly severe forms of periodontal disease. We can affirm that HtrA1 expression in plasma cells could be correlated with the destruction of pathological periodontal tissue, probably due to its ability to trigger the overproduction of MMPs and to increase the inflammatory mediators TNF-α and IL-1β by inhibition of TGF-β. Moreover, epithelial HtrA1 immunostaining suggests a participation of the molecule in the host inflammatory immune responses necessary for the control of periodontal infection. PMID:24979214

  3. Computational Model for the Neutronic Simulation of Pebble Bed Reactor’s Core Using MCNPX

    Directory of Open Access Journals (Sweden)

    J. Rosales

    2014-01-01

    Full Text Available Very high temperature reactor (VHTR designs offer promising performance characteristics; they can provide sustainable energy, improved proliferation resistance, inherent safety, and high temperature heat supply. These designs also promise operation to high burnup and large margins to fuel failure with excellent fission product retention via the TRISO fuel design. The pebble bed reactor (PBR is a design of gas cooled high temperature reactor, candidate for Generation IV of Nuclear Energy Systems. This paper describes the features of a detailed geometric computational model for PBR whole core analysis using the MCNPX code. The validation of the model was carried out using the HTR-10 benchmark. Results were compared with experimental data and calculations of other authors. In addition, sensitivity analysis of several parameters that could have influenced the results and the accuracy of model was made.

  4. Lunar in-core thermionic nuclear reactor power system conceptual design

    Science.gov (United States)

    Mason, Lee S.; Schmitz, Paul C.; Gallup, Donald R.

    1991-01-01

    This paper presents a conceptual design of a lunar in-core thermionic reactor power system. The concept consists of a thermionic reactor located in a lunar excavation with surface mounted waste heat radiators. The system was integrated with a proposed lunar base concept representative of recent NASA Space Exploration Initiative studies. The reference mission is a permanently-inhabited lunar base requiring a 550 kWe, 7 year life central power station. Performance parameters and assumptions were based on the Thermionic Fuel Element (TFE) Verification Program. Five design cases were analyzed ranging from conservative to advanced. The cases were selected to provide sensitivity effects on the achievement of TFE program goals.

  5. Core design study on rock-like oxide fuel light water reactor and improvements of core characteristics

    Science.gov (United States)

    Akie, H.; Takano, H.; Anoda, Y.

    1999-08-01

    A rock-like oxide (ROX) fuel - LWR burning system has been studied for efficient plutonium transmutation. A zirconia based ROX (Zr-ROX) core has problems such as a small negative Doppler coefficient and a large power peaking factor, which causes severe transients in accidents and high fuel temperature even under nominal condition. For the improvement of these characteristics, two approaches were considered: the additives UO 2, ThO 2 and Er 2O 3, or a heterogeneous core with Zr-ROX and UO 2 assemblies. As a result, the combination of the additives UO 2 and Er 2O 3 is found to sufficiently improve the accident behavior, while a further power peaking reduction may be necessary for the Zr-ROX + UO 2 heterogeneous core. The plutonium transmutation rate is extremely high in Zr-ROX assemblies in the heterogeneous core, to be more than 85% and 70%, respectively for weapons- and reactor-grade plutonium. The plutonium transmutation rate becomes smaller in the full-ROX core with the UO 2 or ThO 2 additive, but the annual transmutation amount of plutonium is large, in comparison with the full-MOX fuel core.

  6. Design and performance of a pulse transformer based on Fe-based nanocrystalline core.

    Science.gov (United States)

    Yi, Liu; Xibo, Feng; Lin, Fuchang

    2011-08-01

    A dry-type pulse transformer based on Fe-based nanocrystalline core with a load of 0.88 nF, output voltage of more than 65 kV, and winding ratio of 46 is designed and constructed. The dynamic characteristics of Fe-based nanocrystalline core under the impulse with the pulse width of several microseconds were studied. The pulse width and incremental flux density have an important effect on the pulse permeability, so the pulse permeability is measured under a certain pulse width and incremental flux density. The minimal volume of the toroidal pulse transformer core is determined by the coupling coefficient, the capacitors of the resonant charging circuit, incremental flux density, and pulse permeability. The factors of the charging time, ratio, and energy transmission efficiency in the resonant charging circuit based on magnetic core-type pulse transformer are analyzed. Experimental results of the pulse transformer are in good agreement with the theoretical calculation. When the primary capacitor is 3.17 μF and charge voltage is 1.8 kV, a voltage across the secondary capacitor of 0.88 nF with peak value of 68.5 kV, rise time (10%-90%) of 1.80 μs is obtained.

  7. KüFA safety testing of HTR fuel pebbles irradiated in the High Flux Reactor in Petten

    Energy Technology Data Exchange (ETDEWEB)

    Seeger, O., E-mail: oliver.seeger@rwth-aachen.de [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Safety of Irradiated Nuclear Materials Unit, Postfach 2340, 76125 Karlsruhe (Germany); Laurie, M., E-mail: mathias.laurie@ec.europa.eu [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Safety of Irradiated Nuclear Materials Unit, Postfach 2340, 76125 Karlsruhe (Germany); Abjani, A. El; Ejton, J.; Boudaud, D.; Freis, D.; Carbol, P.; Rondinella, V.V. [European Commission, Joint Research Centre (JRC), Institute for Transuranium Elements (ITU), Safety of Irradiated Nuclear Materials Unit, Postfach 2340, 76125 Karlsruhe (Germany); Fütterer, M. [European Commission, Joint Research Centre (JRC), Institute for Energy and Transport (IET), Nuclear Reactor Integrity Assessment and Knowledge Management Unit, PO Box 2, 1755 ZG Petten (Netherlands); Allelein, H.-J. [Lehrstuhl für Reaktorsicherheit und -technik an der RWTH Aachen, Kackertstraße 9, 52072 Aachen (Germany)

    2016-09-15

    The Cold Finger Apparatus (KühlFinger-Apparatur—KüFA) in operation at JRC-ITU is designed to experimentally scrutinize the effects of Depressurization LOss of Forced Circulation (D-LOFC) accident scenarios on irradiated High Temperature Reactor (HTR) fuel pebbles. Up to 1600 °C, the reference maximum temperature for these accidents, high-quality German HTR fuel pebbles have already demonstrated a small fission product release. This paper discusses and compares the releases obtained from KüFA-testing the pebbles HFR-K5/3 and HFR-EU1/3, which were both irradiated in the High Flux Reactor (HFR) in Petten. We present the time-dependent fractional release of the volatile fission product {sup 137}Cs as well as the fission gas {sup 85}Kr for both pebbles. For HFR-EU1/3 the isotopes {sup 134}Cs and {sup 154}Eu as well as the shorter-lived {sup 110m}Ag have also been measured. A detailed description of the experimental setup and its accuracy is given. The data for the recently tested pebbles is discussed in the context of previous results.

  8. First principles design of a core bioenergetic transmembrane electron-transfer protein.

    Science.gov (United States)

    Goparaju, Geetha; Fry, Bryan A; Chobot, Sarah E; Wiedman, Gregory; Moser, Christopher C; Leslie Dutton, P; Discher, Bohdana M

    2016-05-01

    Here we describe the design, Escherichia coli expression and characterization of a simplified, adaptable and functionally transparent single chain 4-α-helix transmembrane protein frame that binds multiple heme and light activatable porphyrins. Such man-made cofactor-binding oxidoreductases, designed from first principles with minimal reference to natural protein sequences, are known as maquettes. This design is an adaptable frame aiming to uncover core engineering principles governing bioenergetic transmembrane electron-transfer function and recapitulate protein archetypes proposed to represent the origins of photosynthesis. This article is part of a Special Issue entitled Biodesign for Bioenergetics--the design and engineering of electronic transfer cofactors, proteins and protein networks, edited by Ronald L. Koder and J.L. Ross Anderson. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. The design of an asynchronous Tiny RISC TM/TR4101 microprocessor core

    DEFF Research Database (Denmark)

    Christensen, Kåre Tais; Jensen, P.; Korger, P.

    1998-01-01

    This paper presents the design of an asynchronous version of the TR4101 embedded microprocessor core developed by LSI Logic Inc. The asynchronous processor, called ARISC, was designed using the same CAD tools and the same standard cell library that was used to implement the TR4101. The paper...... reports on the design methodology, the architecture, the implementation, and the performance of the ARISC. This includes a comparison with the TR4101, and a detailed breakdown of the power consumption in the ARISC. ARISC is our first attempt at an asynchronous implementation and a number of simplifying...... decisions were made up front. Throughout the entire design we use four-phase handshaking in combination with a normally opaque latch controller. All logic is implemented using static logic standard cells. Despite this the ARISC performs surprisingly well: In 0.35 μm CMOS performance is 74-123 MIPS depending...

  10. Variation Aware Energy-Efficient Methodologies for Homogeneous Many-Core Designs

    Science.gov (United States)

    Srivastav, Meeta

    Earlier designs were driven by the goal of achieving higher performance, but lately, energy efficiency has emerged as an even more important design principle. Strong demand from the consumer electronics drives research in the low power and energy-efficient methodologies. Moreover, with exponential increase in the number of transistors on a chip and with further technology scaling, variability in the design is now of greater concern. Variations can make the design unreliable or the design may suffer from sub-optimal performance. Through the work in this thesis, we present a multi-dimensional investigation into the design of variation aware energy-efficient systems. Our overarching methodology is to use system-level decisions to mitigate undesired effects originating from device-level and circuit-level issues. We first look into the impact of process variation (PV) on energy efficient, scalable through- put many-core DSP systems. In our proposed methodology, we leverage the benefits of aggressive voltage scaling (VS) for obtaining energy efficiency while compensating for the loss in performance by exploiting parallelism present in various DSP designs. We demonstrate this proposed methodology consumes 8% - 77% less power as compared to simple dynamic VS over different workload environments. Later, we show judicious system-level decisions, namely, number of cores, and their operating voltage can greatly mitigate the effects of PV and consequently, improve the energy efficiency of the design. We also present our analysis discussing the impact of aging on the proposed methodology. To validate our proposed system-level approach, design details of a prototype chip fabricated in the 90nm technology node and its findings are also presented. The chip consists of 8 homogeneous FIR cores, which are capable of running from near-threshold to nominal voltages. In the 20-chip population, we observe 7% variation in the speed at nominal voltage (0.9V) and 26% at near threshold

  11. Design of bus-on-chip core for micro-satellite avionics

    Science.gov (United States)

    Liu, Youjun; You, Zheng; Li, Bin; Zhang, Xiangqi; Meng, Ziyang

    2007-11-01

    This paper discusses a layout of bus-on-chip core referring to SoC thinking which is composed of six sections based on a physical chip of FPGA: multi-Processor cache coherence unit, external bus control module, TT&C module, Ethernet Mac interface, EDAC/DMA module, and AMBA bridges. Multi-processor cache coherence unit, as a key part of the bus core, is used to serve the rapid parallel computing by means of the breakthrough of write/read speed of EMS memory and enhances the reliability of OBC with the service of supporting the hot standby of redundancy and the reconfiguration of fault-tolerance. External bus control module is made to support the PnP of external components applying varieties of buses, which is designed by means of soft-core in order to adapt the variation of macro-design and improve the flexibility of external application. TT&C module is the interface of subsystems of telemetry, telecommand and communication, which involves the protocols of HDLC. Ethernet Mac interface based on TCP/IP acts as the access of ISL for formation flying, constellation, etc. EDAC/DMA module mainly manages the data exchange between AMBA bus and RAM, and assigns DMA for the payloads.

  12. Advanced PWR in-core fuel management with optimized gadolinia fuel designs

    Energy Technology Data Exchange (ETDEWEB)

    Berger, H.D.; Neufert, A. [Siemens AG / Power Generation KWU, Nuclear Fuel Cycle, Erlangen (Germany)

    1999-07-01

    Utilities operating LWRs require fuel assemblies and in-core fuel management service, which ensure safe, flexible and cost-effective production of electricity. With the reliability of the fuel having been always the most important requirement, advanced measures to minimize fuel cycle costs are receiving increasing attention in the light of the pressure on costs within the de-regulated power generation markets. The role of in-core fuel management in supporting the goal to minimize fuel cycle costs consists in the development of more demanding core loading strategies, i.e. in the first place more advanced low leakage loading patterns. A prerequisite for this type of loading pattern is the use of an optimized burnable absorber design. Gadolinia as integrated burnable absorber is a very effective means for limiting the critical boron concentration and power peaking factors. Siemens has accumulated extensive experience with Gd-fuel for almost 20 years with e.g. more than 5500 Gd-FA's delivered for PWRs and irradiated up to 65 MWd/kg{sub HM}. Current development efforts for optimizing Gd-fuel are focused on the reduction of the inherent penalties of today's Gd-Fa designs, i.e. reduced average FA enrichment and heavy metal content as well as residual reactivity binding. The most effective way to overcome these drawbacks is the reduction of the Gd{sub 2}O{sub 3} concentration to values of approximately 2 w/o, for which according to recent measurements of the heat conductivity of modern Gd-fuels the reduction of the fissile content in the Gd-rods is no longer necessary. Various feasibility studies have been performed to evaluate the consequences of low-Gd designs for both Siemens PWRs and Non-Siemens PWRs, for which more restrictive boundary conditions with respect to critical boron concentration and peaking factors have to be fulfilled. These studies as well as the first realization of an extended reactor cycle using a low Gd-Fa reload design confirm that the in-core

  13. Comparison of Chamfer and Deep Chamfer Preparation Designs on the Fracture Resistance of Zirconia Core Restorations

    Directory of Open Access Journals (Sweden)

    Ezatollah Jalalian

    2011-06-01

    Full Text Available Background and aims. One of the major problems of all-ceramic restorations is their probable fracture under occlusal force. The aim of the present in vitro study was to compare the effect of two marginal designs (chamfer and deep chamfer on the fracture resistance of all-ceramic restorations, CERCON. Materials and methods. This in vitro study was carried out with single-blind experimental technique. One stainless steel die with 50’ chamfer finish line design (0.8 mm deep was prepared using a milling machine. Ten epoxy resin dies were prepared. The same die was retrieved and 50' chamfer was converted into a deep chamfer design (1 mm. Again ten epoxy resin dies were prepared from the deep chamfer die. Zirconia cores with 0.4 mm thickness and 35 µm cement space were fabricated on the epoxy resin dies (10 chamfer and 10 deep chamfer samples. The zirconia cores were cemented on the epoxy resin dies and underwent a fracture test with a universal testing machine and the samples were investigated from the point of view of the origin of the failure. Results. The mean values of fracture resistance for deep chamfer and chamfer samples were 1426.10±182.60 and 991.75±112.00 N, respectively. Student’s t-test revealed statistically significant differences between the groups. Conclusion. The results indicated a relationship between the marginal design of zirconia cores and their fracture resistance. A deep chamfer margin improved the biomechanical performance of posterior single zirconia crown restorations, which might be attributed to greater thickness and rounded internal angles in deep chamfer margins.

  14. The ARIES-RS power core -- Recent development in Li/V designs

    Energy Technology Data Exchange (ETDEWEB)

    Sze, D.K.; Billone, M.C.; Hua, T.Q. [and others

    1997-04-01

    The ARIES-RS fusion power plant design study is based on reversed-shear (RS) physics with a Li/V (lithium breeder and vanadium structure) blanket. The reversed-shear discharge has been documented in many large tokamak experiments. The plasma in the RS mode has a high beta, low current, and low current drive requirements. Therefore, it is an attractive physics regime for a fusion power plant. The blanket system based on a Li/V has high temperature operating capability, good tritium breeding, excellent high heat flux removal capability, long structural life time, low activation, low after heat and good safety characteristics. For these reasons, the ARIES-RS reactor study selected Li/V as the reference blanket. The combination of attractive physics and attractive blanket engineering is expected to result in a superior power plant design. This paper summarizes the power core design of the ARIES-RS power plant study.

  15. Programming models for many-core architectures: a co-design approach

    NARCIS (Netherlands)

    Rutgers, J.H.

    2014-01-01

    Common many-core processors contain tens of cores and distributed memory. Compared to a multicore system, which only has a few tightly coupled cores sharing a single bus and memory, several complex problems arise. Notably, many cores require many parallel tasks to fully utilize the cores, and

  16. ACT-CCREC Core Research Program: Study Questions and Design. ACT Working Paper Series. WP-2015-01

    Science.gov (United States)

    Cruce, Ty M.

    2015-01-01

    This report provides a non-technical overview of the guiding research questions and research design for the ACT-led core research program conducted on behalf of the GEAR UP College and Career Readiness Evaluation Consortium (CCREC). The core research program is a longitudinal study of the effectiveness of 14 GEAR UP state grants on the academic…

  17. Analysis of Advanced Fuel Assemblies and Core Designs for the Current and Next Generations of LWRs

    Energy Technology Data Exchange (ETDEWEB)

    Ragusa, Jean; Vierow, Karen

    2011-09-01

    The objective of the project is to design and analyze advanced fuel assemblies for use in current and future light water reactors and to assess their ability to reduce the inventory of transuranic elements, while preserving operational safety. The reprocessing of spent nuclear fuel can delay or avoid the need for a second geological repository in the US. Current light water reactor fuel assembly designs under investigation could reduce the plutonium inventory of reprocessed fuel. Nevertheless, these designs are not effective in stabilizing or reducing the inventory of minor actinides. In the course of this project, we developed and analyzed advanced fuel assembly designs with improved thermal transmutation capability regarding transuranic elements and especially minor actinides. These designs will be intended for use in thermal spectrum (e.g., current and future fleet of light water reactors in the US). We investigated various fuel types, namely high burn-up advanced mixed oxides and inert matrix fuels, in various geometrical designs that are compliant with the core internals of current and future light water reactors. Neutronic/thermal hydraulic effects were included. Transmutation efficiency and safety parameters were used to rank and down-select the various designs.

  18. Design of a Resistively Heated Thermal Hydraulic Simulator for Nuclear Rocket Reactor Cores

    Science.gov (United States)

    Litchford, Ron J.; Foote, John P.; Ramachandran, Narayanan; Wang, Ten-See; Anghaie, Samim

    2007-01-01

    A preliminary design study is presented for a non-nuclear test facility which uses ohmic heating to replicate the thermal hydraulic characteristics of solid core nuclear reactor fuel element passages. The basis for this testing capability is a recently commissioned nuclear thermal rocket environments simulator, which uses a high-power, multi-gas, wall-stabilized constricted arc-heater to produce high-temperature pressurized hydrogen flows representative of reactor core environments, excepting radiation effects. Initially, the baseline test fixture for this non-nuclear environments simulator was configured for long duration hot hydrogen exposure of small cylindrical material specimens as a low cost means of evaluating material compatibility. It became evident, however, that additional functionality enhancements were needed to permit a critical examination of thermal hydraulic effects in fuel element passages. Thus, a design configuration was conceived whereby a short tubular material specimen, representing a fuel element passage segment, is surrounded by a backside resistive tungsten heater element and mounted within a self-contained module that inserts directly into the baseline test fixture assembly. With this configuration, it becomes possible to create an inward directed radial thermal gradient within the tubular material specimen such that the wall-to-gas heat flux characteristics of a typical fuel element passage are effectively simulated. The results of a preliminary engineering study for this innovative concept are fully summarized, including high-fidelity multi-physics thermal hydraulic simulations and detailed design features.

  19. IP cores design from specifications to production modeling, verification, optimization, and protection

    CERN Document Server

    Mohamed, Khaled Salah

    2016-01-01

    This book describes the life cycle process of IP cores, from specification to production, including IP modeling, verification, optimization, and protection. Various trade-offs in the design process are discussed, including  those associated with many of the most common memory cores, controller IPs  and system-on-chip (SoC) buses. Readers will also benefit from the author’s practical coverage of new verification methodologies. such as bug localization, UVM, and scan-chain.  A SoC case study is presented to compare traditional verification with the new verification methodologies. ·         Discusses the entire life cycle process of IP cores, from specification to production, including IP modeling, verification, optimization, and protection; ·         Introduce a deep introduction for Verilog for both implementation and verification point of view.  ·         Demonstrates how to use IP in applications such as memory controllers and SoC buses. ·         Describes a new ver...

  20. A Metropolis algorithm combined with Nelder-Mead Simplex applied to nuclear reactor core design

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner F. [Depto. de Modelagem Computacional, Instituto Politecnico, Universidade do Estado do Rio de Janeiro, R. Alberto Rangel, s/n, P.O. Box 972285, Nova Friburgo, RJ 28601-970 (Brazil)], E-mail: wfsacco@iprj.uerj.br; Filho, Hermes Alves; Henderson, Nelio [Depto. de Modelagem Computacional, Instituto Politecnico, Universidade do Estado do Rio de Janeiro, R. Alberto Rangel, s/n, P.O. Box 972285, Nova Friburgo, RJ 28601-970 (Brazil); Oliveira, Cassiano R.E. de [Nuclear and Radiological Engineering Program, George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0405 (United States)

    2008-05-15

    A hybridization of the recently introduced Particle Collision Algorithm (PCA) and the Nelder-Mead Simplex algorithm is introduced and applied to a core design optimization problem which was previously attacked by other metaheuristics. The optimization problem consists in adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the average peak-factor in a three-enrichment-zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. The new metaheuristic performs better than the genetic algorithm, particle swarm optimization, and the Metropolis algorithms PCA and the Great Deluge Algorithm, thus demonstrating its potential for other applications.

  1. Comparative sodium void effects for different advanced liquid metal reactor fuel and core designs

    Energy Technology Data Exchange (ETDEWEB)

    Dobbin, K.D.; Kessler, S.F.; Nelson, J.V.; Gedeon, S.R.; Omberg, R.P.

    1991-07-01

    An analysis of metal-, oxide, and nitride-fueled advanced liquid metal reactor cores was performed to investigate the calculated differences in sodium void reactivity, and to determine the relationship between sodium void reactivity and burnup reactivity swing using the three fuel types. The results of this analysis indicate that nitride fuel has the least positive sodium void reactivity for any given burnup reactivity swing. Thus, it appears that a good design compromise between transient overpower and loss of flow response is obtained using nitride fuel. Additional studies were made to understand these and other nitride advantages. 8 refs., 5 figs., 3 tabs.

  2. Analysis and Design of Double-sided Air core Linear Servo Motor with Trapezoidal Permanent Magnets

    DEFF Research Database (Denmark)

    Zhang, Yuqiu; Yang, Zilong; Yu, Minghu

    2011-01-01

    In order to reduce the thrust ripple of linear servo system, a double-sided air core permanent magnet linear servo motor with trapezoidal shape permanent magnets (TDAPMLSM) is proposed in this paper. An analytical model of the motor for predicting the magnetic field in the air-gap at no......-load is introduced. This model is derived based on the equivalent magnetization intensity method, and its accuracy is validated by using the results obtained from the finite-element method. The key dimensions that affect the air-gap magnetic field are analyzed based on the analytical model, and the design...

  3. Optimal design for crosstalk analysis in 12-core 5-LP mode homogeneous multicore fiber for different lattice structure

    Science.gov (United States)

    Kumar, Dablu; Ranjan, Rakesh

    2018-03-01

    12-Core 5-LP mode homogeneous multicore fibers have been proposed for analysis of inter-core crosstalk and dispersion, with four different lattice structures (circular, 2-ring, square lattice, and triangular lattice) having cladding diameter of 200 μm and a fixed cladding thickness of 35 μm. The core-to-core crosstalk impact has been studied numerically with respect to bending radius, core pitch, transmission distance, wavelength, and core diameter for all 5-LP modes. In anticipation of further reduction in crosstalk levels, the trench-assisted cores have been incorporated for all respective designs. Ultra-low crosstalk (-138 dB/100 km) has been achieved through the triangular lattice arrangement, with trench depth Δ2 = -1.40% for fundamental (LP01) mode. It has been noted that the impact of mode polarization on crosstalk behavior is minor, with difference in crosstalk levels between two polarized spatial modes as ≤0.2 dB. Moreover, the optimized cladding diameter has been obtained for all 5-LP modes for a target value of crosstalk of -50 dB/100 km, with all the core arrangements. The dispersion characteristic has also been analyzed with respect to wavelength, which is nearly 2.5 ps/nm km at operating wavelength 1550 nm. The relative core multiplicity factor (RCMF) for the proposed design is obtained as 64.

  4. GenHtr: a tool for comparative assessment of genetic heterogeneity in microbial genomes generated by massive short-read sequencing

    Directory of Open Access Journals (Sweden)

    Yu GongXin

    2010-10-01

    -consuming when compared to Maq, a popular tool for SNP analysis, GenHtr is able to predict potential multiple variants that pre-exist in the bacterial population as well as SNPs that occur in the highly duplicated gene families. It is expected that, with the proper experimental design, this analysis can improve our understanding of the molecular mechanism underlying the dynamics and the evolution of drug-resistant bacterial pathogens.

  5. Dynamic Modeling and Control Characteristics of the Two-Modular HTR-PM Nuclear Plant

    Directory of Open Access Journals (Sweden)

    Zhe Dong

    2017-01-01

    Full Text Available The modular high temperature gas-cooled reactor (MHTGR is a typical small modular reactor (SMR with inherent safety feature. Due to its high reactor outlet coolant temperature, the MHTGR can be applied not only for electricity production but also as a heat source for industrial complexes. Through multimodular scheme, that is, the superheated steam flows produced by multiple MHTGR-based nuclear supplying system (NSSS modules combined together to drive a common thermal load, the inherent safety feature of MHTGR is applicable to large-scale nuclear plants at any desired power ratings. Since the plant power control technique of traditional single-modular nuclear plants cannot be directly applied to the multimodular plants, it is necessary to develop the power control method of multimodular plants, where dynamical modeling, control design, and performance verification are three main aspects of developing plant control method. In this paper, the study in the power control for two-modular HTR-PM plant is summarized, and the verification results based on numerical simulation are given. The simulation results in the cases of plant power step and ramp show that the plant control characteristics are satisfactory.

  6. Examination and improvement of the SHEM energy group structure for HTR and deep burn HTR design and analysis

    Science.gov (United States)

    Ngeleka, Tholakele Prisca

    The purpose of this study was to study and improve the SHEM energy group structures (281 and 361) and General Atomics-193 energy group structure utilizing the more systematic, consistent, and sophisticated energy group selection method referred to as contribution and point-wise cross-section driven (CPXSD) method. The SHEM-281 and -361 energy group structures were developed for LWR and General Atomics energy group structure was developed for the fast reactors. Pebble bed and Prismatic hexagonal block type fuel are used for cell analysis. DRAGON transport code was used for this task taking advantage of its capability to compute adjoint fluxes for reactor analysis. MCNP5 was used for generation of the reference solution selected due to its accuracy of neutron transport calculations. Comparisons with DRAGON calculations are presented. Pebble fuel element and Prismatic hexagonal block models were created for both codes. In the DRAGON code, analysis are conducted for the starting energy group structure by computing both forward and adjoint fluxes as well as the reaction rates and k-effective. Then forward and adjoint fluxes were used in computing the importance function of the groups, and the groups with high importance function are subdivided accordingly. The whole energy group interval of interest was divided into fast, epithermal and thermal regions. Firstly, the improvement was done for fast region and a new library was created and applied in the fuel cell analysis until the selected target criteria’s were met (10 pcm relative deviation of Δk/k and 1 percent deviation of reaction rate of interest). Then similar procedure was repeated for epithermal and thermal regions. The dominant parameters for each energy region were considered as required such as the fission cross section for fast region, absorption and scattering cross sections for epithermal region and absorption cross section for thermal region and k-effective applied for all energy regions. Pebble fuel element and the Prismatic hexagonal block were analyzed for depletion based on the improved energy group structure SHEM_TPN-531.

  7. Molecular motion regulates the activity of the Mitochondrial Serine Protease HtrA2.

    Science.gov (United States)

    Merski, Matthew; Moreira, Cátia; Abreu, Rui Mv; Ramos, Maria João; Fernandes, Pedro A; Martins, L Miguel; Pereira, Pedro José Barbosa; Macedo-Ribeiro, Sandra

    2017-10-12

    HtrA2 (high-temperature requirement 2) is a human mitochondrial protease that has a role in apoptosis and Parkinson's disease. The structure of HtrA2 with an intact catalytic triad was determined, revealing a conformational change in the active site loops, involving mainly the regulatory LD loop, which resulted in burial of the catalytic serine relative to the previously reported structure of the proteolytically inactive mutant. Mutations in the loops surrounding the active site that significantly restricted their mobility, reduced proteolytic activity both in vitro and in cells, suggesting that regulation of HtrA2 activity cannot be explained by a simple transition to an activated conformational state with enhanced active site accessibility. Manipulation of solvent viscosity highlighted an unusual bi-phasic behavior of the enzymatic activity, which together with MD calculations supports the importance of motion in the regulation of the activity of HtrA2. HtrA2 is an unusually thermostable enzyme (TM=97.3 °C), a trait often associated with structural rigidity, not dynamic motion. We suggest that this thermostability functions to provide a stable scaffold for the observed loop motions, allowing them a relatively free conformational search within a rather restricted volume.

  8. Small Launch Vehicle Design Approaches: Clustered Cores Compared with Multi-Stage Inline Concepts

    Science.gov (United States)

    Waters, Eric D.; Beers, Benjamin; Esther, Elizabeth; Philips, Alan; Threet, Grady E., Jr.

    2013-01-01

    In an effort to better define small launch vehicle design options two approaches were investigated from the small launch vehicle trade space. The primary focus was to evaluate a clustered common core design against a purpose built inline vehicle. Both designs focused on liquid oxygen (LOX) and rocket propellant grade kerosene (RP-1) stages with the terminal stage later evaluated as a LOX/methane (CH4) stage. A series of performance optimization runs were done in order to minimize gross liftoff weight (GLOW) including alternative thrust levels, delivery altitude for payload, vehicle length to diameter ratio, alternative engine feed systems, re-evaluation of mass growth allowances, passive versus active guidance systems, and rail and tower launch methods. Additionally manufacturability, cost, and operations also play a large role in the benefits and detriments for each design. Presented here is the Advanced Concepts Office's Earth to Orbit Launch Team methodology and high level discussion of the performance trades and trends of both small launch vehicle solutions along with design philosophies that shaped both concepts. Without putting forth a decree stating one approach is better than the other; this discussion is meant to educate the community at large and let the reader determine which architecture is truly the most economical; since each path has such a unique set of limitations and potential payoffs.

  9. Development of a standard data base for FBR core nuclear design. 10. Reevaluation of atomic number density of JOYO Mk-II core

    Energy Technology Data Exchange (ETDEWEB)

    Numata, Kazuyuki; Sato, Wakaei [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center; Ishikawa, Makoto; Arii, Yoshio [Nuclear Energy System Incorporation, Tokyo (Japan)

    1999-07-01

    The material composition of JOYO Mk-II core components in its initial core was reevaluated as a part of the effort for developing a standard data base for FBR core nuclear design. The special feature of the reevaluation is to treat the decay of Pu-241 isotope, so that the atomic number densities of Pu-241 and Am-241 in fuel assemblies can be exactly evaluated on the initial critical date, Nov. 22nd, 1982. Further, the atomic number densities of other core components were also evaluated to improve the analytical accuracy. Those include the control rods which were not so strictly evaluated in the past, and the dummy fuels and the neutron sources which were not treated in the analytical model so far. The results of the present reevaluation were as follows: (1) The changes of atomic number densities of the major nuclides such as Pu-239, U-235 and U-238 were about {+-}0.2 to 0.3%. On the other hand, the number density of Pu-241, which was the motivation of the present work, was reduced by 12%. From the fact, the number densities in the past analysis might be based on the isotope measurement of the manufacturing point of time without considering the decay of Pu-241. (2) As the other core components, the number densities of control rods and outer reflector-type A were largely improved. (author)

  10. CORE DESIGNS OF ABWR FOR PROPOSED OF THE FIRST NUCLEAR POWER PLANT IN INDONESIA

    Directory of Open Access Journals (Sweden)

    Yohannes Sardjono

    2015-04-01

    Full Text Available Indonesia as an archipelago has been experiencing high growth industry and energy demand due to high population growth, dynamic economic activities. The total population is around 230 million people and 75 % to the total population is living in Java. The introduction of Nuclear Power Plant on Java Bali electricity grid will be possible in 2022 for 2 GWe, using proven technology reactor like ABWR or others light water reactor with nominal power 1000 MWe. In this case, the rated thermal power for the equilibrium cycles is 3926 MWt, the cycle length is 18 month and overall capacity factor is 87 %. The designs were performed for an 872-fuel bundles ABWR core using GE-11 fuel type in an 9×9 fuel rod arrays with 2 Large Central Water Rods (LCWR. The calculations were divided into two steps; the first is to generate bundle library and the other is to make the thermal and reactivity limits satisfied for the core designs. Toshiba General Electric Bundle lattice Analysis (TGBLA and PANACEA computer codes were used as designs tools. TGBLA is a General Electric proprietary computer code which is used to generate bundle lattice library for fuel designs. PANACEA is General Electric proprietary computer code which is used as thermal hydraulic and neutronic coupled BWR core simulator. This result of core designs describes reactivity and thermal margins i.e.; Maximum Linear Heat Generation rate (MLHGR is lower than 14.4 kW/ft, Minimum Critical Power Ratio (MCPR is upper than 1.25, Hot Excess Reactivity (HOTXS is upper than 1 %Dk at BOC and 0.8 %Dk at 200 MWD/ST and Cold Shutdown Margin Reactivity (CSDM is upper than 1 %Dk. It is concluded that the equilibrium core design using GE-11 fuel bundle type satisfies the core design objectives for the proposed of the firs Indonesia ABWR Nuclear Power Plant. Keywords: The first NPP in Indonesia, ABWR-1000 MWe, and core designs.   Indonesia adalah sebagai negara kepulauan yang laju pertumbuhan industri, energi, penduduk

  11. Optimal design at inner core of the shaped pyramidal truss structure

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Sung-Uk; Yang, Dong-Yol [Department of Mechanical Engineering, KAIST 291 Daehak-ro (373-1 Guseong-dong), Yuseong-gu, Dae-jeon, 305-701 (Korea, Republic of)

    2013-12-16

    Sandwich material is a type of composite material with lightweight, high strength, good dynamic properties and high bending stiffness-to-weight ratio. This can be found well such structures in the nature (for example, internal structure of bones, plants, etc.). New trend which prefers eco-friendly products and energy efficiency is emerging in industries recently. Demand for materials with high strength and light weight is also increasing. In line with these trends, researches about manufacturing methods of sandwich material have been actively conducted. In this study, a sandwich structure named as “Shaped Pyramidal Truss Structure” is proposed to improve mechanical strength and to apply a manufacturing process suitable for massive production. The new sandwich structure was designed to enhance compressive strength by changing the cross-sectional shape at the central portion of the core. As the next step, optimization of the shape was required. Optimization technique used here was the SZGA(Successive Zooming Genetic Algorithm), which is one of GA(Genetic Algorithm) methods gradually reducing the area of design variable. The objective function was defined as moment of inertia of the cross-sectional shape of the strut. The control points of cubic Bezier curve, which was assumed to be the shape of the cross section, were used as design variables. By using FEM simulation, it was found that the structure exhibited superior mechanical properties compared to the simple design of the prior art.

  12. America's Next Great Ship: Space Launch System Core Stage Transitioning from Design to Manufacturing

    Science.gov (United States)

    Birkenstock, Benjamin; Kauer, Roy

    2014-01-01

    The Space Launch System (SLS) Program is essential to achieving the Nation's and NASA's goal of human exploration and scientific investigation of the solar system. As a multi-element program with emphasis on safety, affordability, and sustainability, SLS is becoming America's next great ship of exploration. The SLS Core Stage includes avionics, main propulsion system, pressure vessels, thrust vector control, and structures. Boeing manufactures and assembles the SLS core stage at the Michoud Assembly Facility (MAF) in New Orleans, LA, a historical production center for Saturn V and Space Shuttle programs. As the transition from design to manufacturing progresses, the importance of a well-executed manufacturing, assembly, and operation (MA&O) plan is crucial to meeting performance objectives. Boeing employs classic techniques such as critical path analysis and facility requirements definition as well as innovative approaches such as Constraint Based Scheduling (CBS) and Cirtical Chain Project Management (CCPM) theory to provide a comprehensive suite of project management tools to manage the health of the baseline plan on both a macro (overall project) and micro level (factory areas). These tools coordinate data from multiple business systems and provide a robust network to support Material & Capacity Requirements Planning (MRP/CRP) and priorities. Coupled with these tools and a highly skilled workforce, Boeing is orchestrating the parallel buildup of five major sub assemblies throughout the factory. Boeing and NASA are transforming MAF to host state of the art processes, equipment and tooling, the most prominent of which is the Vertical Assembly Center (VAC), the largest weld tool in the world. In concert, a global supply chain is delivering a range of structural elements and component parts necessary to enable an on-time delivery of the integrated Core Stage. SLS is on plan to launch humanity into the next phase of space exploration.

  13. Influence of power level and fuel type on safety and economy of the simplified pebble bed HTR concept

    Energy Technology Data Exchange (ETDEWEB)

    Van Heek, A.I.; Kuijper, J.C.; De Haas, J.B.M. [Netheerlands Energy Research Foundation ECN, Petten (Netherlands)

    1998-09-01

    For three different power levels, 20, 40 and 150 MWth, the PAP-HTR has been studied. This is an HTR Module concept that has been simplified in such a way that the continuously defuelling system has been eliminated and no defuelling takes place during a period of several years. Two core heatup scenarios have been simulated. It has been shown that in all cases the maximum fuel pebble temperature remains below 1600C, the temperature above which fuel degradation would start to occur, also after the reactor has gone critical again and the power level has been stabilized by itself. Fuel and gas temperature distributions are compared as well. The maximum pebble temperature before recriticality is higher for the loss of coolant (LOCA) scenario than for the loss of flow (LOFA) case, but the equilibrium maximum temperature after recriticality turns out to be higher for the pressurized case, because of the higher equilibrium power level. The equilibrium power level is a much smaller fraction of the nominal power level for the large 150 MWth system than for the smaller systems, due to the lower rate of cooling down of the large system after initiation of the accident. Therefore the equilibrium maximum temperature stays within acceptable limits for the large system too. The effects of the use of thorium fuel on the core height and waste radiotoxicity have been compared with the case of uranium fuel. Although it is widely believed that burnt thorium fuel would be cleaner than spent uranium fuel in terms of radiotoxicity, this did not appear to be more pronounced for this reactor concept than for e.g. PWRs. The relationship of power level and energy price is obvious for this power range. The use of thorium with highly enriched uranium could bring an additional economical advantage because of the lower core height needed for the same power level as the uranium case. With thorium a higher burnup can be attained, through which fuel pebbles can be added at a slower rate. The size of

  14. Influence of Polymorphisms in the HTR3A and HTR3B Genes on Experimental Pain and the Effect of the 5-HT3 Antagonist Granisetron.

    Directory of Open Access Journals (Sweden)

    Sofia Louca Jounger

    Full Text Available The aim of this study was to investigate experimentally if 5-HT3 single nucleotide polymorphisms (SNP contribute to pain perception and efficacy of the 5-HT3-antagonist granisetron and sex differences. Sixty healthy participants were genotyped regarding HTR3A (rs1062613 and HTR3B (rs1176744. First, pain was induced by bilateral hypertonic saline injections (HS, 5.5%, 0.2 mL into the masseter muscles. Thirty min later the masseter muscle on one side was pretreated with 0.5 mL granisetron (1 mg/mL and on the other side with 0.5 mL placebo (isotonic saline followed by another HS injection (0.2 mL. Pain intensity, pain duration, pain area and pressure pain thresholds (PPTs were assessed after each injection. HS evoked moderate pain, with higher intensity in the women (P = 0.023, but had no effect on PPTs. None of the SNPs influenced any pain variable in general, but compared to men, the pain area was larger in women carrying the C/C (HTR3A (P = 0.015 and pain intensity higher in women with the A/C alleles (HTR3B (P = 0.019. Pre-treatment with granisetron reduced pain intensity, duration and area to a lesser degree in women (P < 0.05, but the SNPs did not in general influence the efficacy of granisetron. Women carrying the C/T & T/T (HTR3A genotype had less reduction of pain intensity (P = 0.041 and area (P = 0.005, and women with the C/C genotype (HTR3B had less reduction of pain intensity (P = 0.030, duration (P = 0.030 and area compared to men (P = 0.017. In conclusion, SNPs did not influence experimental muscle pain or the effect of granisetron on pain variables in general, but there were some sex differences in pain variables that seem to be influenced by genotypes. However, due to the small sample size further research is needed before any firm conclusions can be drawn.

  15. Chemical and Colloidal Stability of Carboxylated Core-Shell Magnetite Nanoparticles Designed for Biomedical Applications

    Directory of Open Access Journals (Sweden)

    László Tiszlavicz

    2013-07-01

    Full Text Available Despite the large efforts to prepare super paramagnetic iron oxide nanoparticles (MNPs for biomedical applications, the number of FDA or EMA approved formulations is few. It is not known commonly that the approved formulations in many instances have already been withdrawn or discontinued by the producers; at present, hardly any approved formulations are produced and marketed. Literature survey reveals that there is a lack for a commonly accepted physicochemical practice in designing and qualifying formulations before they enter in vitro and in vivo biological testing. Such a standard procedure would exclude inadequate formulations from clinical trials thus improving their outcome. Here we present a straightforward route to assess eligibility of carboxylated MNPs for biomedical tests applied for a series of our core-shell products, i.e., citric acid, gallic acid, poly(acrylic acid and poly(acrylic acid-co-maleic acid coated MNPs. The discussion is based on physicochemical studies (carboxylate adsorption/desorption, FTIR-ATR, iron dissolution, zeta potential, particle size, coagulation kinetics and magnetization measurements and involves in vitro and in vivo tests. Our procedure can serve as an example to construct adequate physico-chemical selection strategies for preparation of other types of core-shell nanoparticles as well.

  16. The association between HTR2C gene polymorphisms and the metabolic syndrome in patients with schizophrenia.

    Science.gov (United States)

    Mulder, Hans; Franke, Barbara; van der-Beek van der, Annemarie Aart; Arends, Johan; Wilmink, Frederik W; Scheffer, Hans; Egberts, Antoine C G

    2007-08-01

    The use of antipsychotics is associated with metabolic side effects, which put patients with schizophrenia or related disorders at risk for cardiovascular morbidity. The high interindividual variability in antipsychotic-induced metabolic abnormalities suggests that genetic makeup is a possible determinant. In this cross-sectional study, we investigated whether genotypes of the HTR2C receptor are associated with the metabolic syndrome in patients using antipsychotics. Patients were identified from a schizophrenia disease management program. In this program, patients' blood pressure, triglycerides, high-density lipoprotein-cholesterol, and waist circumference are measured regularly during follow-up. The primary end point of our study was the prevalence of the metabolic syndrome as classified by a modified version of the National Cholesterol Education Program's Adult Treatment Panel III. Primary determinants were polymorphisms in the HTR2C receptor gene (HTR2C:c.1-142948[GT]n, rs3813928 [-997 G/A], rs3813929 [-759 C/T], rs518147 [-697 G/C], and rs1414334 [C > G]). The included patients (n = 112) mainly (>80%) used atypical antipsychotics (clozapine, olanzapine, and risperidone). Carriership of the variant alleles of the HTR2C polymorphisms rs518147, rs1414334, and HTR2C:c.1-142948(GT)n was associated with an increased risk of the metabolic syndrome (adjusted odds ratio [OR], 2.62 [95% confidence interval {CI}, 1.00-6.85]; OR, 4.09 [95% CI, 1.41-11.89]; and OR, 3.12 [95% CI, 1.13-8.16]), respectively. Our findings suggest that HTR2C genotypes are associated with antincreased risk of metabolic syndrome in patients taking antipsychotics.

  17. Recombinant outer membrane vesicles carrying Chlamydia muridarum HtrA induce antibodies that neutralize chlamydial infection in vitro

    Science.gov (United States)

    Bartolini, Erika; Ianni, Elvira; Frigimelica, Elisabetta; Petracca, Roberto; Galli, Giuliano; Berlanda Scorza, Francesco; Norais, Nathalie; Laera, Donatello; Giusti, Fabiola; Pierleoni, Andrea; Donati, Manuela; Cevenini, Roberto; Finco, Oretta; Grandi, Guido; Grifantini, Renata

    2013-01-01

    Background Outer membrane vesicles (OMVs) are spheroid particles released by all Gram-negative bacteria as a result of the budding out of the outer membrane. Since they carry many of the bacterial surface-associated proteins and feature a potent built-in adjuvanticity, OMVs are being utilized as vaccines, some of which commercially available. Recently, methods for manipulating the protein content of OMVs have been proposed, thus making OMVs a promising platform for recombinant, multivalent vaccines development. Methods Chlamydia muridarum DO serine protease HtrA, an antigen which stimulates strong humoral and cellular responses in mice and humans, was expressed in Escherichia coli fused to the OmpA leader sequence to deliver it to the OMV compartment. Purified OMVs carrying HtrA (CM rHtrA-OMV) were analyzed for their capacity to induce antibodies capable of neutralizing Chlamydia infection of LLC-MK2 cells in vitro. Results CM rHtrA-OMV immunization in mice induced antibodies that neutralize Chlamydial invasion as judged by an in vitro infectivity assay. This was remarkably different from what observed with an enzymatically functional recombinant HtrA expressed in, and purified from the E. coli cytoplasm (CM rHtrA). The difference in functionality between anti-CM rHtrA and anti-CM rHtrA-OMV antibodies was associated to a different pattern of protein epitopes recognition. The epitope recognition profile of anti-CM HtrA-OMV antibodies was similar to that induced in mice during Chlamydial infection. Conclusions When expressed in OMVs HtrA appears to assume a conformation similar to the native one and this results in the elicitation of functional immune responses. These data further support the potentiality of OMVs as vaccine platform. PMID:24009891

  18. HtrA1 in human urothelial bladder cancer: a secreted protein and a potential novel biomarker.

    Science.gov (United States)

    Lorenzi, Teresa; Lorenzi, Maria; Altobelli, Emma; Marzioni, Daniela; Mensà, Emanuela; Quaranta, Alexia; Paolinelli, Francesca; Morroni, Manrico; Mazzucchelli, Roberta; De Luca, Antonio; Procopio, Antonio Domenico; Baldi, Alfonso; Muzzonigro, Giovanni; Montironi, Rodolfo; Castellucci, Mario

    2013-12-01

    Our aim was to analyze the expression of the serine protease HtrA1 in human bladder tissue and urine in order to point out its possible association with the presence of urothelial bladder cancer. Bladder tissue and urine specimens from cancer patients with different tumor grades and stages (n = 68) and from individuals with cystitis (n = 16) were collected along with biopsy specimens and urine from healthy individuals (n = 68). For the first time, we demonstrated by immunohistochemistry that HtrA1 protein is produced by bladder urothelium in both physiological and inflammatory conditions, whereas it is not detectable in urothelial cancer cells regardless of tumor grade and stage. A different HtrA1 expression between normal-looking and neoplastic bladder tissue, despite similar HtrA1 mRNA levels, was also found by western blotting, which disclosed the presence of two forms of HtrA1, a native form of ∼50 kDa and an autocatalytic form of ∼38 kDa. Our investigations documented the presence of the two forms of HtrA1 also in urine. The ∼38 kDa form was significantly down-regulated in neoplastic tissue, whereas significantly higher amounts of both HtrA1 forms were found in urine from cancer patients compared with both healthy subjects and patients with cystitis. Our findings suggest that HtrA1 is a downexpressed molecule since an early stage of bladder urothelial carcinoma development and that urinary HtrA1 protein may be considered, if successfully validated, as an early and highly sensitive and specific biomarker for this neoplasia (the sensitivity and specificity of HtrA1 are 92.65% and 95.59%, respectively). Copyright © 2013 UICC.

  19. Low HtrA1 expression in patients with long‑standing ulcerative colitis and colorectal cancer.

    Science.gov (United States)

    Altobelli, Emma; Latella, Giovanni; Morroni, Manrico; Licini, Caterina; Tossetta, Giovanni; Mazzucchelli, Roberta; Profeta, Valerio F; Coletti, Gino; Leocata, Pietro; Castellucci, Mario; Guerrieri, Mario; Petrocelli, Reimondo; De Berardis, Berardo; De Padova, Marina; Di Leonardo, Gabriella; Paladini, Antonella; Mignosi, Filippo; Quaglione, Gina; Fagnano, Roberto; Marzioni, Daniela

    2017-07-01

    The association between inflammatory bowel disease (IBD) and colorectal cancer (CRC) is being increasingly investigated. HtrA1 overexpression inhibits cell growth and proliferation by influencing apoptosis, invasiveness and migration of tumour cells. In the present study, HtrA1 expression was analysed in 228 colon tissue samples from patients with CRC, adenoma with high-grade dysplasia (AHD), adenoma with low-grade dysplasia (ALD), ulcerative colitis of >10 year duration (UCL), ulcerative colitis of <5 year duration (UCS) and colonic diverticulitis (D), and was compared with its expression in normal colon tissues (NCTs) collected 5 cm from the CRC lesion and in healthy colon mucosa (HC), to establish whether HtrA1 can serve as a biomarker for these conditions. All tissue specimens came from Italian Caucasian subjects. The main finding of the present study was that HtrA1 expression was significantly reduced in CRC and UCL tissues compared with that observed in both NCT and HC samples and with tissues from the other patients. In particular, a similar HtrA1 expression was detected in the stromal compartment of UCL and CRC samples. In contrast, the HtrA1 level was significantly lower (p=0.0008) in UCL compared with UCS tissues, suggesting an inverse relationship between HtrA1 expression and ulcerative colitis duration. HtrA1 immunostaining in the stromal compartment of AHD and ALD tissues showed no differences compared with the HC tissues. No data are available on the immunohistochemical localization of HtrA1 in CRC or IBD. The present findings suggest that HtrA1 could serve as a marker to identify UCL patients at high risk of developing CRC.

  20. Design of an overmoderated fuel and a full MOX core for plutonium consumption in boiling water reactors

    Energy Technology Data Exchange (ETDEWEB)

    Francois, J.L. E-mail: franmar@prodigy.net.mx; Campo, C.M. del; Hernandez, J

    2002-11-01

    The use of uranium-plutonium mixed oxide fuel (MOX) in light water reactors (LWR) is nowadays a current practice in several countries. Generally 1/3 of the reactor core is loaded with MOX fuel assemblies and the other 2/3 with uranium assemblies. Nevertheless the plutonium utilization could be more effective if the full core could be loaded with MOX fuel. In this paper the design of a boiling water reactor (BWR) core fully loaded with an overmoderated MOX fuel design is investigated. The design of overmoderated BWR MOX fuel assemblies based on a 10x10 lattice are developed, these designs improve the neutron spectrum and the plutonium consumption rate, compared with standard MOX assemblies. In order to increase the moderator to fuel ratio two approaches are followed: in the first approach, 8 or 12 fuel rods are replaced by water rods in the 10x10 lattice; in the second approach, an 11x11 lattice with 24 water rods is designed with an active fuel length very close to the standard MOX assembly. The results of the depletion behavior and the main steady state core parameters are presented. The feasibility of a full core loaded with the 11x11 overmoderated MOX fuel assembly is verified. This design take advantage of the softer spectrum comparable to the 10x10 lattice with 12 water rods but with thermal limits comparable to the standard MOX fuel assembly.

  1. Cost-based optimization of a nuclear reactor core design: a preliminary model

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner F.; Alves Filho, Hermes [Universidade do Estado do Rio de Janeiro (UERJ), Nova Friburgo, RJ (Brazil). Inst. Politecnico. Dept. de Modelagem Computacional]. E-mails: wfsacco@iprj.uerj.br; halves@iprj.uerj.br; Pereira, Claudio M.N.A. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil). Div. de Reatores]. E-mail: cmnap@ien.gov.br

    2007-07-01

    A new formulation of a nuclear core design optimization problem is introduced in this article. Originally, the optimization problem consisted in adjusting several reactor cell parameters, such as dimensions, enrichment and materials, in order to minimize the radial power peaking factor in a three-enrichment zone reactor, considering restrictions on the average thermal flux, criticality and sub-moderation. Here, we address the same problem using the minimization of the fuel and cladding materials costs as the objective function, and the radial power peaking factor as an operational constraint. This cost-based optimization problem is attacked by two metaheuristics, the standard genetic algorithm (SGA), and a recently introduced Metropolis algorithm called the Particle Collision Algorithm (PCA). The two algorithms are submitted to the same computational effort and their results are compared. As the formulation presented is preliminary, more elaborate models are also discussed (author)

  2. PVDF core-free actuator for Braille displays: design, fabrication process, and testing

    Science.gov (United States)

    Levard, Thomas; Diglio, Paul J.; Lu, Sheng-Guo; Gorny, Lee J.; Rahn, Christopher D.; Zhang, Q. M.

    2011-04-01

    Refreshable Braille displays require many, small diameter actuators to move the pins. The electrostrictive P(VDF-TrFECFE) terpolymer can provide the high strain and actuation force under modest electric fields that are required of this application. In this paper, we develop core-free tubular actuators and integrate them into a 3 × 2 Braille cell. The films are solution cast, stretched to 6 μm thick, electroded, laminated into a bilayer, rolled into a 2 mm diameter tube, bonded, and provided with top and bottom contacts. Experimental testing of 17 actuators demonstrates significant strains (up to 4%). A novel Braille cell is designed and fabricated using six of these actuators.

  3. Shielding and activation calculations around the reactor core for the MYRRHA ADS design

    Directory of Open Access Journals (Sweden)

    Ferrari Anna

    2017-01-01

    Full Text Available In the frame of the FP7 European project MAXSIMA, an extensive simulation study has been done to assess the main shielding problems in view of the construction of the MYRRHA accelerator-driven system at SCK·CEN in Mol (Belgium. An innovative method based on the combined use of the two state-of-the-art Monte Carlo codes MCNPX and FLUKA has been used, with the goal to characterize complex, realistic neutron fields around the core barrel, to be used as source terms in detailed analyses of the radiation fields due to the system in operation, and of the coupled residual radiation. The main results of the shielding analysis are presented, as well as the construction of an activation database of all the key structural materials. The results evidenced a powerful way to analyse the shielding and activation problems, with direct and clear implications on the design solutions.

  4. Shielding and activation calculations around the reactor core for the MYRRHA ADS design

    Science.gov (United States)

    Ferrari, Anna; Mueller, Stefan; Konheiser, J.; Castelliti, D.; Sarotto, M.; Stankovskiy, A.

    2017-09-01

    In the frame of the FP7 European project MAXSIMA, an extensive simulation study has been done to assess the main shielding problems in view of the construction of the MYRRHA accelerator-driven system at SCK·CEN in Mol (Belgium). An innovative method based on the combined use of the two state-of-the-art Monte Carlo codes MCNPX and FLUKA has been used, with the goal to characterize complex, realistic neutron fields around the core barrel, to be used as source terms in detailed analyses of the radiation fields due to the system in operation, and of the coupled residual radiation. The main results of the shielding analysis are presented, as well as the construction of an activation database of all the key structural materials. The results evidenced a powerful way to analyse the shielding and activation problems, with direct and clear implications on the design solutions.

  5. Optimal Design of Multistage Two-Dimensional Cellular-Cored Sandwich Panel Heat Exchanger

    Directory of Open Access Journals (Sweden)

    Yongcun Zhang

    2014-08-01

    Full Text Available For a two-dimensional (2D cellular-cored sandwich panel heat exchanger, there exists an optimum cell size to achieve the maximum heat transfer with the prescribed pressure drop when the length is fixed and the two plates are isothermal. However, in engineering design, it is difficult to find 2D cellular materials with the ideal cell size because the cell size selected must be from those commercially available, which are discrete, not continuous. In order to obtain the maximum heat dissipation, an innovative design scheme is proposed for the sandwich panel heat exchanger which is divided into multiple stages in the direction of fluid flow where the 2D cellular material in each stage has a specific cell size. An analytical model is presented to evaluate the thermal performance of the multistage sandwich panel heat exchanger when all 2D cellular materials have the same porosity. Also, a new parameter named equivalent cell size (ECS is defined, which is dependent on the cell size and length of cellular material in all stages. Results show that the maximum heat dissipation design of the multistage sandwich panel heat exchanger can be converted to make the ECS equal to the optimal cell size of the single-stage exchanger.

  6. Design Review Report for formal review of safety class features of exhauster system for rotary mode core sampling

    Energy Technology Data Exchange (ETDEWEB)

    JANICEK, G.P.

    2000-06-08

    Report documenting Formal Design Review conducted on portable exhausters used to support rotary mode core sampling of Hanford underground radioactive waste tanks with focus on Safety Class design features and control requirements for flammable gas environment operation and air discharge permitting compliance.

  7. Evaluation of core modeling effect on transients for multi-flow zone design of SFR

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Andong; Choi, Yong Won [Korea Institute of Nuclear Safety, Daejeon (Korea, Republic of)

    2016-10-15

    SFR core is composed of different types of assemblies including fuel driver, reflector, blanket, control, safety drivers and other drivers. Modeling of different types of assemblies is inevitable in general. But modeling of core flow zones of with different channels needs a lot of effort and could be a challenge for system code modeling due to its limitation on the number of modeling components. In this study, core modeling effect on SFR transient was investigated with flow-zone model and averaged inner core channel model to improve modeling efficiency and validation of simplified core model for EBR-II loss of flow transient case with the modified TRACE code for SFRs. Core modeling effect on the loss flow transient was analyzed with flow-zoned channel model, single averaged inner core model and highest flow channel with averaged inner core channel model for EBR-II SHRT-17 test core. Case study showed that estimations of transient pump and channel flow as well as channel outlet temperatures were similar for all cases macroscopically. Comparing the result of the base case (flow-zone channel inner core model) and the case 2 (highest flow channel considered averaged inner core channel model), flow and channel outlet temperature response were closer than the case1 (single averaged inner core model)

  8. Chlamydia trachomatis responds to heat shock, penicillin induced persistence, and IFN-gamma persistence by altering levels of the extracytoplasmic stress response protease HtrA

    Directory of Open Access Journals (Sweden)

    Mathews Sarah A

    2008-11-01

    Full Text Available Abstract Background Chlamydia trachomatis, an obligate intracellular human pathogen, is the most prevalent bacterial sexually transmitted infection worldwide and a leading cause of preventable blindness. HtrA is a virulence and stress response periplasmic serine protease and molecular chaperone found in many bacteria. Recombinant purified C. trachomatis HtrA has been previously shown to have both activities. This investigation examined the physiological role of Chlamydia trachomatis HtrA. Results The Chlamydia trachomatis htrA gene complemented the lethal high temperature phenotype of Escherichia coli htrA- (>42°C. HtrA levels were detected to increase by western blot and immunofluorescence during Chlamydia heat shock experiments. Confocal laser scanning microscopy revealed a likely periplasmic localisation of HtrA. During penicillin induced persistence of Chlamydia trachomatis, HtrA levels (as a ratio of LPS were initially less than control acute cultures (20 h post infection but increased to more than acute cultures at 44 h post infection. This was unlike IFN-γ persistence where lower levels of HtrA were observed, suggesting Chlamydia trachomatis IFN-γ persistence does not involve a broad stress response. Conclusion The heterologous heat shock protection for Escherichia coli, and increased HtrA during cell wall disruption via penicillin and heat shock, indicates an important role for HtrA during high protein stress conditions for Chlamydia trachomatis.

  9. The Effect of Core and Veneering Design on the Optical Properties of Polyether Ether Ketone.

    Science.gov (United States)

    Zeighami, S; Mirmohammadrezaei, S; Safi, M; Falahchai, S M

    2017-12-01

    This study aimed to evaluate the effect of core shade and core and veneering thickness on color parameters and translucency of polyether ether ketone (PEEK). Sixty PEEK discs (0.5 and 1 mm in thickness) with white and dentine shades were veneered with A2 shade indirect composite resin with 0.5, 1 and 1.5 mm thickness (n=5). Cores without the veneering material served as controls for translucency evaluation. Color parameters were measured by a spectroradiometer. Color difference (ΔE₀₀) and translucency parameters (TP) were computed. Data were analyzed using one-way ANOVA and Tukey's test (for veneering thickness) and independent t-test (for core shade and thickness) via SPSS 20.0 (p⟨0.05). Regarding the veneering thickness, white cores of 0.5 mm thickness showed significant differences in all color parameters. In white cores of 1 mm thickness and dentine cores of 0.5 and 1 mm thickness, there were statistically significant differences only in L∗, a∗ and h∗. The mean TP was significantly higher in all white cores of 1 mm thickness than dentine cores of 1 mm. Considering ΔE₀₀=3.7 as clinically unacceptable, only three groups had higher mean ΔE₀₀ values. Core shade, core thickness, and the veneering thickness affected the color and translucency of PEEK restorations. Copyright© 2017 Dennis Barber Ltd.

  10. The gravitational attraction algorithm: a new metaheuristic applied to a nuclear reactor core design optimization problem

    Energy Technology Data Exchange (ETDEWEB)

    Sacco, Wagner F.; Oliveira, Cassiano R.E. de [Georgia Institute of Technology, Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering. Nuclear and Radiological Engineering Program]. E-mail: wagner.sacco@me.gatech.edu; cassiano.oliveira@nre.gatech.edu; Pereira, Claudio M.N.A. [Instituto de Engenharia Nuclear (IEN), Rio de Janeiro, RJ (Brazil)]. E-mail: cmnap@ien.gov.br

    2005-07-01

    A new metaheuristic called 'Gravitational Attraction Algorithm' (GAA) is introduced in this article. It is an analogy with the gravitational force field, where a body attracts another proportionally to both masses and inversely to their distances. The GAA is a populational algorithm where, first of all, the solutions are clustered using the Fuzzy Clustering Means (FCM) algorithm. Following that, the gravitational forces of the individuals in relation to each cluster are evaluated and this individual or solution is displaced to the cluster with the greatest attractive force. Once it is inside this cluster, the solution receives small stochastic variations, performing a local exploration. Then the solutions are crossed over and the process starts all over again. The parameters required by the GAA are the 'diversity factor', which is used to create a random diversity in a fashion similar to genetic algorithm's mutation, and the number of clusters for the FCM. GAA is applied to the reactor core design optimization problem which consists in adjusting several reactor cell parameters in order to minimize the average peak-factor in a 3-enrichment-zone reactor, considering operational restrictions. This problem was previously attacked using the canonical genetic algorithm (GA) and a Niching Genetic Algorithm (NGA). The new metaheuristic is then compared to those two algorithms. The three algorithms are submitted to the same computational effort and GAA reaches the best results, showing its potential for other applications in the nuclear engineering field as, for instance, the nuclear core reload optimization problem. (author)

  11. Design and synthesis of hyperstructured molecules based on cyclophosphazene core for multiphoton absorption

    Energy Technology Data Exchange (ETDEWEB)

    Naik, K. Praveen Kumar [School of Chemistry, University of Hyderabad, Hyderabad 500046 India (India); Sreeramulu, V. [School of Physics, University of Hyderabad, Hyderabad 500046 India (India); CNR-IFN CSMFO Laboratory, Via alla Cascata, 56/C Povo, Trento (Italy); Ramya, E. [School of Physics, University of Hyderabad, Hyderabad 500046 India (India); Muralidharan, K., E-mail: murali@uohyd.ac.in [School of Chemistry, University of Hyderabad, Hyderabad 500046 India (India); Rao, D. Narayana [School of Physics, University of Hyderabad, Hyderabad 500046 India (India)

    2016-09-01

    Cyclophosphazene based hyperstructured molecules were synthesized through simple nucleophilic substitution reactions. All these molecules were characterized by multinuclear NMR, MALDI and HRMS spectral data. Third order nonlinear optical properties of the hyperstructured molecules were measured using Z-scan technique with 532 nm, picosecond (ps) laser and 800 nm, femtosecond (fs) laser pulses. The molecules showed reverse saturable absorption on excitation at both 532 nm and 800 nm, which could be attributed to the two-photon absorption (2 PA) and three-photon absorption (3 PA), respectively. The 2 PA and 3 PA cross section values exhibited by the molecules based on cyclophosphazene are as high as 527 GM and 1.86 × 10{sup −76} cm{sup −6} s{sup 2} photon{sup −1}, respectively. The 2PA, 3PA coefficients and optical limiting properties make them suitable candidates for nonlinear optical devices in the visible and near IR range. - Graphical abstract: The hyperstructured molecules based on cyclophosphazene core were synthesized and used for multiphoton absorption. Open aperture Z-scan curves of hyper structured molecules at the excitation of (a) picosecond laser and (b) femtosecond laser representing multiphoton absorption properties are reported. - Highlights: • Two hyperstructured molecules based on cyclophosphazene core are designed for multiphoton absorption. • NLO properties are measured using Z-scan technique at 532 nm and 800 nm wavelengths. • The molecules were tested for the optical limiting applications at 532 nm and 800 nm laser pulses.

  12. Identification of E-cadherin signature motifs functioning as cleavage sites for Helicobacter pylori HtrA

    Science.gov (United States)

    Schmidt, Thomas P.; Perna, Anna M.; Fugmann, Tim; Böhm, Manja; Jan Hiss; Haller, Sarah; Götz, Camilla; Tegtmeyer, Nicole; Hoy, Benjamin; Rau, Tilman T.; Neri, Dario; Backert, Steffen; Schneider, Gisbert; Wessler, Silja

    2016-03-01

    The cell adhesion protein and tumour suppressor E-cadherin exhibits important functions in the prevention of gastric cancer. As a class-I carcinogen, Helicobacter pylori (H. pylori) has developed a unique strategy to interfere with E-cadherin functions. In previous studies, we have demonstrated that H. pylori secretes the protease high temperature requirement A (HtrA) which cleaves off the E-cadherin ectodomain (NTF) on epithelial cells. This opens cell-to-cell junctions, allowing bacterial transmigration across the polarised epithelium. Here, we investigated the molecular mechanism of the HtrA-E-cadherin interaction and identified E-cadherin cleavage sites for HtrA. Mass-spectrometry-based proteomics and Edman degradation revealed three signature motifs containing the [VITA]-[VITA]-x-x-D-[DN] sequence pattern, which were preferentially cleaved by HtrA. Based on these sites, we developed a substrate-derived peptide inhibitor that selectively bound and inhibited HtrA, thereby blocking transmigration of H. pylori. The discovery of HtrA-targeted signature sites might further explain why we detected a stable 90 kDa NTF fragment during H. pylori infection, but also additional E-cadherin fragments ranging from 105 kDa to 48 kDa in in vitro cleavage experiments. In conclusion, HtrA targets E-cadherin signature sites that are accessible in in vitro reactions, but might be partially masked on epithelial cells through functional homophilic E-cadherin interactions.

  13. Common variants in the gene for the serotonin receptor 6 (HTR6) do ...

    Indian Academy of Sciences (India)

    We selected HTR6 (serotonin receptor 6) as a candidate gene to test for associations with obesity since earlier studies have shown that mice with a disrupted serotonin receptor are less prone to become obese on a high-fat diet. We genotyped three tagSNPs (rs6658108, rs6699866 and rs9659997) and included one ...

  14. HTR2C Gene Polymorphisms and the Metabolic Syndrome in Patients With Schizophrenia A Replication Study

    NARCIS (Netherlands)

    Mulder, Hans; Cohen, Dan; Scheffer, Hans; Gispen-de Wied, Christine; Arends, Johan; Wilmink, Frederik W.; Franke, Barbara; Egberts, Antoine C. G.

    In a previous study, we found an association between 5-hydroxytryptamine (serotonin) receptor 2C (HTR2C) polymorphisms and the occurrence of the metabolic syndrome in patients using antipsychotics. In the current study, we set out to replicate our findings in another sample of patients and to

  15. Common variants in the gene for the serotonin receptor 6 (HTR6) do ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 89; Issue 4. Common variants in the gene for the serotonin receptor 6 (HTR6) do not contribute to obesity. Armand V. Peeters Sigri Beckers An Verrijken Peter Roevens Pieter J. Peeters Luc F. Van Gaal Wim Van Hul. Research Note Volume 89 Issue 4 December 2010 pp 469- ...

  16. Design and analysis of a toroidal tester for the measurement of core losses under axial compressive stress

    Science.gov (United States)

    Alatawneh, Natheer; Rahman, Tanvir; Lowther, David A.; Chromik, Richard

    2017-06-01

    Electric machine cores are subjected to mechanical stresses due to manufacturing processes. These stresses include radial, circumferential and axial components that may have significant influences on the magnetic properties of the electrical steel and hence, on the output and efficiencies of electrical machines. Previously, most studies of iron losses due to mechanical stress have considered only radial and circumferential components. In this work, an improved toroidal tester has been designed and developed to measure the core losses and the magnetic properties of electrical steel under a compressive axial stress. The shape of the toroidal ring has been verified using 3D stress analysis. Also, 3D electromagnetic simulations show a uniform flux density distribution in the specimen with a variation of 0.03 T and a maximum average induction level of 1.5 T. The developed design has been prototyped, and measurements were carried out using a steel sample of grade 35WW300. Measurements show that applying small mechanical stresses normal to the sample thickness rises the delivered core losses, then the losses decrease continuously as the stress increases. However, the drop in core losses at high stresses does not go lower than the free-stress condition. Physical explanations for the observed trend of core losses as a function of stress are provided based on core loss separation to the hysteresis and eddy current loss components. The experimental results show that the effect of axial compressive stress on magnetic properties of electrical steel at high level of inductions becomes less pronounced.

  17. Design of a Polymer-Based Hollow-Core Bandgap Fiber for Low-Loss Terahertz Transmission

    DEFF Research Database (Denmark)

    Barh, Ajanta; Varshney, Ravi K.; Pal, Bishnu P.

    2016-01-01

    We use numerical simulations to design a hollow-core microstructured polymer optical fiber (HC-mPOF) suitable for broadband, terahertz (THz) pulse transmission with relatively low losses and small dispersion. The HC-mPOF consists of a central large air-core surrounded by periodically arranged wav...... of non-zero values of the longitudinal wavevector. We have achieved PBG over a broad spectral range (bandwidth similar to 400 GHz) ranging from 1.65 to 2.05 THz in the proposed HC-mPOF. The achievable loss coefficient in our designed HC-mPOF is...

  18. Core Thermal-Hydraulic Design of a Sodium Cooled Fast Reactor for the U/TRU Fuel Modification

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Sun Rock; Cho, Chung Ho; Kim, Young Gyun; Song, Hoon; Park, Won Seok; Kim, Sang Ji [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2011-05-15

    The Korea Atomic energy Research Institute (KAERI) has been developing an advanced SFR design technology with the final goal of constructing a demonstration plant by 2028. The main objective of the SFR demonstration plant is to verify TRU metal fuel performance, large-scale reactor operation, and transmutation ability of high-level wastes. However, in the early stage, the SFR will run on low enriched uranium fuel due to a lack of TRU fuel qualification. After sequential evaluations of the fuel performance, the fissile fuel material will transform from uranium to LTRU (LWR-TRU), and then finally to MTRU (Mixed TRU of LTRU and recycled TRU). At the same time, the core configurations will be modified to meet the nuclear design requirements. Therefore, there is also a strong need to ensure a proper cooling capability during modifications of the entire core. In this work, the core thermal-hydraulic design for U/TRU fuel modification is performed using the SLTHEN (Steady-State LMR Thermal-Hydraulic Analysis Code Based on ENERGY Model) code. As the power distribution in a reactor core is not uniform, it requires a suitable flow allocation to each assembly. There are two ways of allocating the flow rates depending on the orifice positions. The inner officering scheme locates orifice plates in the lower part of the fuel assembly. Therefore, it is possible that the flow distribution is redesigned according to the core configurations. On the other hand, the outer officering scheme fixes orifice plates within the receptacle body throughout the entire plant lifetime. This has the advantage lower of fabrication costs and operating errors but included insufficient design flexibility. This paper provides comparative studies of orifice position for the core thermal-hydraulic design

  19. SHAPE analysis of the htrA RNA thermometer from Salmonella enterica.

    Science.gov (United States)

    Choi, Edric K; Ulanowicz, Kelsey A; Nguyen, Yen Anh H; Frandsen, Jane K; Mitton-Fry, Rachel M

    2017-10-01

    RNA thermometers regulate expression of some genes involved in virulence of pathogenic bacteria such as Yersinia, Neisseria, and Salmonella They often function through temperature-dependent conformational changes that alter accessibility of the ribosome-binding site. The 5'-untranslated region (UTR) of the htrA mRNA from Salmonella enterica contains a very short RNA thermometer. We have systematically characterized the structure and dynamics of this thermometer at single-nucleotide resolution using SHAPE (selective 2'-hydroxyl acylation analyzed by primer extension) assays. Our results confirm that the htrA thermometer adopts the predicted hairpin conformation at low temperatures, with conformational change occurring over a physiological temperature regime. Detailed SHAPE melting curves for individual nucleotides suggest that the thermometer unfolds in a cooperative fashion, with nucleotides from both upper and lower portions of the stem gaining flexibility at a common transition temperature. Intriguingly, analysis of an extended htrA 5' UTR sequence revealed not only the presence of the RNA thermometer, but also an additional, stable upstream structure. We generated and analyzed point mutants of the htrA thermometer, revealing elements that modulate its stability, allowing the hairpin to melt under the slightly elevated temperatures experienced during the infection of a warm-blooded host. This work sheds light on structure-function relationships in htrA and related thermometers, and it also illustrates the utility of SHAPE assays for detailed study of RNA thermometer systems. © 2017 Choi et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

  20. Modular Approach to Launch Vehicle Design Based on a Common Core Element

    Science.gov (United States)

    Creech, Dennis M.; Threet, Grady E., Jr.; Philips, Alan D.; Waters, Eric D.; Baysinger, Mike

    2010-01-01

    With a heavy lift launch vehicle as the centerpiece of our nation's next exploration architecture's infrastructure, the Advanced Concepts Office at NASA's Marshall Space Flight Center initiated a study to examine the utilization of elements derived from a heavy lift launch vehicle for other potential launch vehicle applications. The premise of this study is to take a vehicle concept, which has been optimized for Lunar Exploration, and utilize the core stage with other existing or near existing stages and boosters to determine lift capabilities for alternative missions. This approach not only yields a vehicle matrix with a wide array of capabilities, but also produces an evolutionary pathway to a vehicle family based on a minimum development and production cost approach to a launch vehicle system architecture, instead of a purely performance driven approach. The upper stages and solid rocket booster selected for this study were chosen to reflect a cross-section of: modified existing assets in the form of a modified Delta IV upper stage and Castor-type boosters; potential near term launch vehicle component designs including an Ares I upper stage and 5-segment boosters; and longer lead vehicle components such as a Shuttle External Tank diameter upper stage. The results of this approach to a modular launch system are given in this paper.

  1. Preliminary scoping safety analyses of the limiting design basis protected accidents for the Fast Flux Test Facility tritium production core

    Energy Technology Data Exchange (ETDEWEB)

    Heard, F.J.

    1997-11-19

    The SAS4A/SASSYS-l computer code is used to perform a series of analyses for the limiting protected design basis transient events given a representative tritium and medical isotope production core design proposed for the Fast Flux Test Facility. The FFTF tritium and isotope production mission will require a different core loading which features higher enrichment fuel, tritium targets, and medical isotope production assemblies. Changes in several key core parameters, such as the Doppler coefficient and delayed neutron fraction will affect the transient response of the reactor. Both reactivity insertion and reduction of heat removal events were analyzed. The analysis methods and modeling assumptions are described. Results of the analyses and comparison against fuel pin performance criteria are presented to provide quantification that the plant protection system is adequate to maintain the necessary safety margins and assure cladding integrity.

  2. DYNAMICO-1.0, an icosahedral hydrostatic dynamical core designed for consistency and versatility

    Science.gov (United States)

    Dubos, T.; Dubey, S.; Tort, M.; Mittal, R.; Meurdesoif, Y.; Hourdin, F.

    2015-10-01

    The design of the icosahedral dynamical core DYNAMICO is presented. DYNAMICO solves the multi-layer rotating shallow-water equations, a compressible variant of the same equivalent to a discretization of the hydrostatic primitive equations in a Lagrangian vertical coordinate, and the primitive equations in a hybrid mass-based vertical coordinate. The common Hamiltonian structure of these sets of equations is exploited to formulate energy-conserving spatial discretizations in a unified way. The horizontal mesh is a quasi-uniform icosahedral C-grid obtained by subdivision of a regular icosahedron. Control volumes for mass, tracers and entropy/potential temperature are the hexagonal cells of the Voronoi mesh to avoid the fast numerical modes of the triangular C-grid. The horizontal discretization is that of Ringler et al. (2010), whose discrete quasi-Hamiltonian structure is identified. The prognostic variables are arranged vertically on a Lorenz grid with all thermodynamical variables collocated with mass. The vertical discretization is obtained from the three-dimensional Hamiltonian formulation. Tracers are transported using a second-order finite-volume scheme with slope limiting for positivity. Explicit Runge-Kutta time integration is used for dynamics, and forward-in-time integration with horizontal/vertical splitting is used for tracers. Most of the model code is common to the three sets of equations solved, making it easier to develop and validate each piece of the model separately. Representative three-dimensional test cases are run and analyzed, showing correctness of the model. The design permits to consider several extensions in the near future, from higher-order transport to more general dynamics, especially deep-atmosphere and non-hydrostatic equations.

  3. Efficient optimization of hollow-core photonic crystal fiber design using the finite-element method

    DEFF Research Database (Denmark)

    Holzlöhner, Ronald; Burger, Sven; Roberts, John

    2006-01-01

    We employ a finite-element (FE) solver with adaptive grid refinement to model hollow-core photonic crystal fibers (HC-PCFs) whose core is formed from 19 omitted cladding unit cells. We optimize the complete fiber geometry for minimal field intensity at material/air interfaces, which indicates low...

  4. DCMIP2016: a review of non-hydrostatic dynamical core design and intercomparison of participating models

    Directory of Open Access Journals (Sweden)

    P. A. Ullrich

    2017-12-01

    Full Text Available Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier–Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and their individual successes suggest that no perfect model exists. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 non-hydrostatic dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP workshop and summer school. This review includes a choice of model grid, variable placement, vertical coordinate, prognostic equations, temporal discretization, and the diffusion, stabilization, filters, and fixers employed by each system.

  5. DCMIP2016: a review of non-hydrostatic dynamical core design and intercomparison of participating models

    Science.gov (United States)

    Ullrich, Paul A.; Jablonowski, Christiane; Kent, James; Lauritzen, Peter H.; Nair, Ramachandran; Reed, Kevin A.; Zarzycki, Colin M.; Hall, David M.; Dazlich, Don; Heikes, Ross; Konor, Celal; Randall, David; Dubos, Thomas; Meurdesoif, Yann; Chen, Xi; Harris, Lucas; Kühnlein, Christian; Lee, Vivian; Qaddouri, Abdessamad; Girard, Claude; Giorgetta, Marco; Reinert, Daniel; Klemp, Joseph; Park, Sang-Hun; Skamarock, William; Miura, Hiroaki; Ohno, Tomoki; Yoshida, Ryuji; Walko, Robert; Reinecke, Alex; Viner, Kevin

    2017-12-01

    Atmospheric dynamical cores are a fundamental component of global atmospheric modeling systems and are responsible for capturing the dynamical behavior of the Earth's atmosphere via numerical integration of the Navier-Stokes equations. These systems have existed in one form or another for over half of a century, with the earliest discretizations having now evolved into a complex ecosystem of algorithms and computational strategies. In essence, no two dynamical cores are alike, and their individual successes suggest that no perfect model exists. To better understand modern dynamical cores, this paper aims to provide a comprehensive review of 11 non-hydrostatic dynamical cores, drawn from modeling centers and groups that participated in the 2016 Dynamical Core Model Intercomparison Project (DCMIP) workshop and summer school. This review includes a choice of model grid, variable placement, vertical coordinate, prognostic equations, temporal discretization, and the diffusion, stabilization, filters, and fixers employed by each system.

  6. Design and analysis of high-power segmented-core trench-assisted Yb-free erbium doped fiber amplifier

    Science.gov (United States)

    Gaur, Ankita; Rastogi, Vipul

    2017-10-01

    Limited power handling capacity of single mode fiber compels to design effective-single mode large-core fiber for high power amplifiers. This article proposes a 0.15 NA, large-mode-area, bend-insensitive, Yb-free EDFA for the selective amplification of fundamental mode. The fiber uses a leaky design to ensure fundamental-mode amplification by higher-order mode discrimination. The segmented-core design in the fiber helps in achieving large-mode-area. The annular segments and low index trench in the fiber control the leakage losses and gains of the modes. We show an EDFA design with 811 μm2 mode-area, 0.014 dB bending loss for 10 mm diameter loop at 1530 nm wavelength and highly selective single-mode output. Our calculations also show a linear increase in the output signal power with pump power with a slope efficiency of 52.8%.

  7. Design and Performance Improvements of the Prototype Open Core Flywheel Energy Storage System

    Science.gov (United States)

    Pang, D.; Anand, D. K. (Editor); Kirk, J. A. (Editor)

    1996-01-01

    A prototype magnetically suspended composite flywheel energy storage (FES) system is operating at the University of Maryland. This system, designed for spacecraft applications, incorporates recent advances in the technologies of composite materials, magnetic suspension, and permanent magnet brushless motor/generator. The current system is referred to as an Open Core Composite Flywheel (OCCF) energy storage system. This paper will present design improvements for enhanced and robust performance. Initially, when the OCCF prototype was spun above its first critical frequency of 4,500 RPM, the rotor movement would exceed the space available in the magnetic suspension gap and touchdown on the backup mechanical bearings would occur. On some occasions it was observed that, after touchdown, the rotor was unable to re-suspend as the speed decreased. Additionally, it was observed that the rotor would exhibit unstable oscillations when the control system was initially turned on. Our analysis suggested that the following problems existed: (1) The linear operating range of the magnetic bearings was limited due to electrical and magnetic saturation; (2) The inductance of the magnetic bearings was affecting the transient response of the system; (3) The flywheel was confined to a small movement because mechanical components could not be held to a tight tolerance; and (4) The location of the touchdown bearing magnifies the motion at the pole faces of the magnetic bearings when the linear range is crucial. In order to correct these problems an improved design of the flywheel energy storage system was undertaken. The magnetic bearings were re-designed to achieve a large linear operating range and to withstand load disturbances of at least 1 g. The external position transducers were replaced by a unique design which were resistant to magnetic field noise and allowed cancellation of the radial growth of the flywheel at high speeds. A central rod was utilized to ensure the concentricity

  8. Overview on R and D and design activities for the ITER core charge exchange spectroscopy diagnostic system

    Energy Technology Data Exchange (ETDEWEB)

    Biel, W., E-mail: w.biel@fz-juelich.de [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Baross, T. [KFKI RMKI, EURATOM Association, PO Box 49, H-1521 Budapest (Hungary); Bourauel, P. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Dunai, D. [KFKI RMKI, EURATOM Association, PO Box 49, H-1521 Budapest (Hungary); Durkut, M. [TNO Science and Industry, Partner in ITER-NL, P.O. Box 155, 2600 AD Delft (Netherlands); Erdei, G. [BME, EURATOM Association, PO Box 91, H-1521 Budapest (Hungary); Hawkes, N. [Association EURATOM/CCFE, OX14 3DB Abingdon (United Kingdom); Hellermann, M. von [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster and ITER-NL, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Hogenbirk, A. [Nuclear Research and Consultancy Group V.o.F., Petten (Netherlands); Jaspers, R. [Department of Applied Physics, Eindhoven University of Technology (Netherlands); Kiss, G. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany); Klinkhamer, F. [TNO Science and Industry, Partner in ITER-NL, P.O. Box 155, 2600 AD Delft (Netherlands); Koning, J.F. [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, partner in the Trilateral Euregio Cluster and ITER-NL, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Kotov, V.; Krasikov, Y.; Krimmer, A. [Institut fuer Energieforschung - Plasmaphysik, Forschungszentrum Juelich Gmbh, Association EURATOM-FZJ, member of Trilateral Euregio Cluster, 52425 Juelich (Germany)

    2011-10-15

    The ITER core charge exchange recombination spectroscopy (core CXRS) diagnostic system is designed to provide experimental access to various measurement quantities in the ITER core plasma such as ion densities, temperatures and velocities. The implementation of the approved CXRS diagnostic principle on ITER faces significant challenges: First, a comparatively low CXRS signal intensity is expected, together with a high noise level due to bremsstrahlung, while the requested measurement accuracy and stability for the core CXRS system go far beyond the level commonly achieved in present-day fusion experiments. Second, the lifetime of the first mirror surface is limited due to either erosion by fast particle bombardment or deposition of impurities. Finally, the hostile technical environment on ITER imposes challenging boundary conditions for the diagnostic integration and operation, including high neutron loads, electro-magnetic loads, seismic events and a limited access for maintenance. A brief overview on the R and D and design activities for the core CXRS system is presented here, while the details are described in parallel papers.

  9. Distinct 3D Architecture and Dynamics of the Human HtrA2(Omi Protease and Its Mutated Variants.

    Directory of Open Access Journals (Sweden)

    Artur Gieldon

    Full Text Available HtrA2(Omi protease controls protein quality in mitochondria and plays a major role in apoptosis. Its HtrA2S306A mutant (with the catalytic serine routinely disabled for an X-ray study to avoid self-degradation is a homotrimer whose subunits contain the serine protease domain (PD and the regulatory PDZ domain. In the inactive state, a tight interdomain interface limits penetration of both PDZ-activating ligands and PD substrates into their respective target sites. We successfully crystalized HtrA2V226K/S306A, whose active counterpart HtrA2V226K has had higher proteolytic activity, suggesting higher propensity to opening the PD-PDZ interface than that of the wild type HtrA2. Yet, the crystal structure revealed the HtrA2V226K/S306A architecture typical of the inactive protein. To get a consistent interpretation of crystallographic data in the light of kinetic results, we employed molecular dynamics (MD. V325D inactivating mutant was used as a reference. Our simulations demonstrated that upon binding of a specific peptide ligand NH2-GWTMFWV-COOH, the PDZ domains open more dynamically in the wild type protease compared to the V226K mutant, whereas the movement is not observed in the V325D mutant. The movement relies on a PDZ vs. PD rotation which opens the PD-PDZ interface in a lid-like (budding flower-like in trimer fashion. The noncovalent hinges A and B are provided by two clusters of interfacing residues, harboring V325D and V226K in the C- and N-terminal PD barrels, respectively. The opening of the subunit interfaces progresses in a sequential manner during the 50 ns MD simulation. In the systems without the ligand only minor PDZ shifts relative to PD are observed, but the interface does not open. Further activation-associated events, e.g. PDZ-L3 positional swap seen in any active HtrA protein (vs. HtrA2, were not observed. In summary, this study provides hints on the mechanism of activation of wtHtrA2, the dynamics of the inactive HtrA2V325D

  10. Designing core-shell 3D photonic crystal lattices for negative refraction

    Science.gov (United States)

    Chernow, Victoria F.; Ng, Ryan C.; Greer, Julia R.

    2017-02-01

    We use a plane wave expansion method to define parameters for the fabrication of 3-dimensional (3D) core-shell photonic crystals (PhCs) with lattice geometries that are capable of all-angle negative refraction (AANR) in the midinfrared centered around 8.0 μm. We discuss the dependence of the AANR frequency range on the volume fraction of solid within the lattice and on the ratio of the low index core material to the high index shell material. Following the constraints set by simulations, we fabricate two types of nanolattice PhCs: (1) polymer core-germanium shell and (2) amorphous carbon core-germanium shell to enable experimental observation of 3D negative refraction and related dispersion phenomena at infrared and eventually optical frequencies.

  11. Study on Reduced-Moderation Water Reactor (RMWR) core design. Joint research report (FY1998-1999)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-09-01

    The Reduce-Moderation Water Reactor (RMWR) is a next generation water-cooled reactor aiming at effective utilization of uranium resource, high burn-up and long operation cycle, and plutonium multi-recycle. Japan Atomic Energy Research Institute (JAERI) started a joint research program for conceptual design of RMWR core in collaboration with the Japan Atomic Power Company (JAPC) since 1998. The research area includes the RMWR core conceptual designs, development of analysis methods for rector physics and thermal-hydraulics to design the RMWR cores with higher accuracy and preparation of MOX critical experiment to confirm the feasibility from the reactor physics point of view. The present report describes the results of joint research program 'RMWR core design Phase 1' performed by JAERI and JAPC in FY 1998 and 1999. The results obtained from the joint research program are as follows: Conceptual design study on the RMWR core has been performed. A core concept with a conversion ratio more than about 1 is basically feasible to multiple recycling of plutonium. Investigating core characteristics at the equilibrium, some promising core concepts to satisfy above aims have been established. As for BWR-type concepts with negative void reactivity coefficients, three types of design have been obtained as follows; (1) one feasible to attain high conversion ratio about 1.1, (2) one feasible to attain operation cycle of about 2 years and burn-up of about 60 GWd/t with conversion ratio more than 1 or (3) one in simple design based on the ABWR assembly and without blanket attaining conversion ratio more than 1. And as for PWR-type concepts with negative void reactivity coefficients, two types of design have been obtained as follows; (1) one feasible to attain high conversion ratio about 1.05 by using heavy water as a coolant and (2) one feasible to attain conversion ratio about l by using light water. In the study of nuclear calculation method, a reactor analysis code

  12. System design specification for rotary mode core sample trucks No. 2, 3, and 4 programmable logic controller

    Energy Technology Data Exchange (ETDEWEB)

    Dowell, J.L.; Akers, J.C.

    1995-12-31

    The system this document describes controls several functions of the Core Sample Truck(s) used to obtain nuclear waste samples from various underground storage tanks at Hanford. The system will monitor the sampling process and provide alarms and other feedback to insure the sampling process is performed within the prescribed operating envelope. The intended audience for this document is anyone associated with rotary or push mode core sampling. This document describes the Alarm and Control logic installed on Rotary Mode Core Sample Trucks (RMCST) {number_sign}2, 3, and 4. It is intended to define the particular requirements of the RMCST alarm and control operation (not defined elsewhere) sufficiently for detailed design to implement on a Programmable Logic Controller (PLC).

  13. Biomechanical evaluation of bending strength of spinal pedicle screws, including cylindrical, conical, dual core and double dual core designs using numerical simulations and mechanical tests.

    Science.gov (United States)

    Amaritsakul, Yongyut; Chao, Ching-Kong; Lin, Jinn

    2014-09-01

    Pedicle screws are used for treating several types of spinal injuries. Although several commercial versions are presently available, they are mostly either fully cylindrical or fully conical. In this study, the bending strengths of seven types of commercial pedicle screws and a newly designed double dual core screw were evaluated by finite element analyses and biomechanical tests. All the screws had an outer diameter of 7 mm, and the biomechanical test consisted of a cantilever bending test in which a vertical point load was applied using a level arm of 45 mm. The boundary and loading conditions of the biomechanical tests were applied to the model used for the finite element analyses. The results showed that only the conical screws with fixed outer diameter and the new double dual core screw could withstand 1,000,000 cycles of a 50-500 N cyclic load. The new screw, however, exhibited lower stiffness than the conical screw, indicating that it could afford patients more flexible movements. Moreover, the new screw produced a level of stability comparable to that of the conical screw, and it was also significantly stronger than the other screws. The finite element analysis further revealed that the point of maximum tensile stress in the screw model was comparable to the point at which fracture occurred during the fatigue test. Copyright © 2014 IPEM. Published by Elsevier Ltd. All rights reserved.

  14. Modeling of the Reactor Core Isolation Cooling Response to Beyond Design Basis Operations - Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Cardoni, Jeffrey N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Wilson, Chisom Shawn [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Morrow, Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Osborn, Douglas [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gauntt, Randall O. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-12-01

    Efforts are being pursued to develop and qualify a system-level model of a reactor core isolation (RCIC) steam-turbine-driven pump. The model is being developed with the intent of employing it to inform the design of experimental configurations for full-scale RCIC testing. The model is expected to be especially valuable in sizing equipment needed in the testing. An additional intent is to use the model in understanding more fully how RCIC apparently managed to operate far removed from its design envelope in the Fukushima Daiichi Unit 2 accident. RCIC modeling is proceeding along two avenues that are expected to complement each other well. The first avenue is the continued development of the system-level RCIC model that will serve in simulating a full reactor system or full experimental configuration of which a RCIC system is part. The model reasonably represents a RCIC system today, especially given design operating conditions, but lacks specifics that are likely important in representing the off-design conditions a RCIC system might experience in an emergency situation such as a loss of all electrical power. A known specific lacking in the system model, for example, is the efficiency at which a flashing slug of water (as opposed to a concentrated jet of steam) could propel the rotating drive wheel of a RCIC turbine. To address this specific, the second avenue is being pursued wherein computational fluid dynamics (CFD) analyses of such a jet are being carried out. The results of the CFD analyses will thus complement and inform the system modeling. The system modeling will, in turn, complement the CFD analysis by providing the system information needed to impose appropriate boundary conditions on the CFD simulations. The system model will be used to inform the selection of configurations and equipment best suitable of supporting planned RCIC experimental testing. Preliminary investigations with the RCIC model indicate that liquid water ingestion by the turbine

  15. Universal Design for Learning: speech-language pathologists and their teams making the common core curriculum accessible.

    Science.gov (United States)

    Staskowski, Maureen; Hardin, Susan; Klein, Mike; Wozniak, Carrie

    2012-05-01

    The Universal Design for Learning (UDL) framework was named in the supporting documents for the Common Core State Standards (CCSS) as a means of helping all students, especially those with disabilities, to meet and exceed the rigorous expectations. This article will describe the principles of UDL, show how educational teams use the framework to design instruction to teach the CCSS with examples from science and English language arts, and finally explore how the implementation of UDL provides an opportunity for speech-language pathologists to play a critical role in school improvement and instructional design and support. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  16. Steroid hormones modulate galectin-1 in the trophoblast HTR-8/SVneocell line

    Directory of Open Access Journals (Sweden)

    Bojić-Trbojević Žanka

    2008-01-01

    Full Text Available The effects of steroids on galectin-1 (gal-1 were studied in HTR-8/SVneo cells by immunocytochemistry, cell-based ELISA, the MTT proliferation test and the Matrigel TM invasion test. Dexamethasone (DEX, progesterone (PRG, and mifepristone (RU486 were used. Gal-1 was modulated in a steroid- and dose-dependent manner by DEX, which mildly but significantly stimulated production at low concentrations (0.1-10 nM, and inhibited it at 100 nM, while the effects of PRG and RU486 were opposite. HTR-8/SVneo cell invasion of Matrigel was significantly decreased in the presence of DEX and lactose. The obtained data support the proposed regulatory role of steroids in trophoblast gal-1 production.

  17. Long-term stability and corrosion of high temperature alloys in HTR test helium

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, J.P.; Glaze, F.J.; Ali-Khan, I.

    1977-02-15

    Since the first test station was started up, about 60 long-time experiments have been completed within 2 years. Their running times lay between 100 and 9,000 hours. With these relatively short experimental times, the effect of strongly contaminated helium (simulation of the start-up phase of an HTR) on the long-time strength of the test materials could not be ascertained. Several results are graphically plotted. The micrographs below show several results from metallographic studies on long-time specimens in lengthwise section. The type and depth of corrosion attack by the HTR helium atmosphere varies considerably with the materials being studied. Specimens which were exposed to various helium contaminations in long-time test stations were subjected to metallographic study (KFA Juelich--CIIR Oslo). These studies showed that the corrosion behavior of the materials is more strongly influenced by the composition of the alloy than by the concentration of the helium contaminants.

  18. Verification of the CENTRM Module for Adaptation of the SCALE Code to NGNP Prismatic and PBR Core Designs

    Energy Technology Data Exchange (ETDEWEB)

    Ganapol, Barry; Maldonado, Ivan

    2014-01-23

    The generation of multigroup cross sections lies at the heart of the very high temperature reactor (VHTR) core design, whether the prismatic (block) or pebble-bed type. The design process, generally performed in three steps, is quite involved and its execution is crucial to proper reactor physics analyses. The primary purpose of this project is to develop the CENTRM cross-section processing module of the SCALE code package for application to prismatic or pebble-bed core designs. The team will include a detailed outline of the entire processing procedure for application of CENTRM in a final report complete with demonstration. In addition, they will conduct a thorough verification of the CENTRM code, which has yet to be performed. The tasks for this project are to: Thoroughly test the panel algorithm for neutron slowing down; Develop the panel algorithm for multi-materials; Establish a multigroup convergence 1D transport acceleration algorithm in the panel formalism; Verify CENTRM in 1D plane geometry; Create and test the corresponding transport/panel algorithm in spherical and cylindrical geometries; and, Apply the verified CENTRM code to current VHTR core design configurations for an infinite lattice, including assessing effectiveness of Dancoff corrections to simulate TRISO particle heterogeneity.

  19. Thermal Hydraulics Design and Analysis Methodology for a Solid-Core Nuclear Thermal Rocket Engine Thrust Chamber

    Science.gov (United States)

    Wang, Ten-See; Canabal, Francisco; Chen, Yen-Sen; Cheng, Gary; Ito, Yasushi

    2013-01-01

    Nuclear thermal propulsion is a leading candidate for in-space propulsion for human Mars missions. This chapter describes a thermal hydraulics design and analysis methodology developed at the NASA Marshall Space Flight Center, in support of the nuclear thermal propulsion development effort. The objective of this campaign is to bridge the design methods in the Rover/NERVA era, with a modern computational fluid dynamics and heat transfer methodology, to predict thermal, fluid, and hydrogen environments of a hypothetical solid-core, nuclear thermal engine the Small Engine, designed in the 1960s. The computational methodology is based on an unstructured-grid, pressure-based, all speeds, chemically reacting, computational fluid dynamics and heat transfer platform, while formulations of flow and heat transfer through porous and solid media were implemented to describe those of hydrogen flow channels inside the solid24 core. Design analyses of a single flow element and the entire solid-core thrust chamber of the Small Engine were performed and the results are presented herein

  20. Design of a Modular E-Core Flux Concentrating Axial Flux Machine: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Husain, Tausif; Sozer, Yilmaz; Husain, Iqbal; Muljadi, Eduard

    2015-08-24

    In this paper a novel E-Core axial flux machine is proposed. The machine has a double-stator, single-rotor configuration with flux-concentrating ferrite magnets and pole windings across each leg of an E-Core stator. E-Core stators with the proposed flux-concentrating rotor arrangement result in better magnet utilization and higher torque density. The machine also has a modular structure facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis. facilitating simpler construction. This paper presents a single-phase and a three-phase version of the E-Core machine. Case studies for a 1.1-kW, 400-rpm machine for both the single-phase and three-phase axial flux machines are presented. The results are verified through 3D finite element analysis.

  1. STUDI PEMODELAN DAN PERHITUNGAN TRANSPORT MONTE CARLO DALAM TERAS HTR PEBBLE BED

    Directory of Open Access Journals (Sweden)

    Zuhair .

    2013-01-01

    Full Text Available Konsep sistem energi VHTR baik yang berbahan bakar pebble (VHTR pebble bed maupun blok prismatik (VHTR prismatik menarik perhatian fisikawan reaktor nuklir. Salah satu kelebihan teknologi bahan bakar bola adalah menawarkan terobosan teknologi pengisian bahan bakar tanpa harus menghentikan produksi listrik. Selain itu, partikel bahan bakar pebble dengan kernel uranium oksida (UO2 atau uranium oksikarbida (UCO yang dibalut TRISO dan pelapisan silikon karbida (SiC dianggap sebagai opsi utama dengan pertimbangan performa tinggi pada burn-up bahan bakar dan temperatur tinggi. Makalah ini mendiskusikan pemodelan dan perhitungan transport Monte Carlo dalam teras HTR pebble bed. HTR pebble bed adalah reaktor berpendingin gas temperatur tinggi dan bermoderator grafit dengan kemampuan kogenerasi. Perhitungan dikerjakan dengan program MCNP5 pada temperatur 1200 K. Pustaka data nuklir energi kontinu ENDF/B-V dan ENDF/B-VI dimanfaatkan untuk melengkapi analisis. Hasil perhitungan secara keseluruhan menunjukkan konsistensi dengan nilai keff yang hampir sama untuk pustaka data nuklir yang digunakan. Pustaka ENDF/B-VI (66c selalu memproduksi keff lebih besar dibandingkan ENDF/B-V (50c maupun ENDF/B-VI (60c dengan bias kurang dari 0,25%. Kisi BCC memprediksi keff hampir selalu lebih kecil daripada kisi lainnya, khususnya FCC. Nilai keff kisi BCC lebih dekat dengan kisi FCC dengan bias kurang dari 0,19% sedangkan dengan kisi SH bias perhitungannya kurang dari 0,22%. Fraksi packing yang sedikit berbeda (BCC= 61%, SH= 60,459% tidak membuat bias perhitungan menjadi berbeda jauh. Estimasi keff ketiga model kisi menyimpulkan bahwa model BCC lebih bisa diadopsi dalam perhitungan HTR pebble bed dibandingkan model FCC dan SH. Verifikasi hasil estimasi ini perlu dilakukan dengan simulasi Monte Carlo atau bahkan program deterministik lainnya guna optimisasi perhitungan teras reaktor temperatur tinggi.   Kata-kunci: kernel, TRISO, bahan bakar pebble, HTR pebble bed

  2. Idebenone and resveratrol extend lifespan and improve motor function of HtrA2 knockout mice.

    Directory of Open Access Journals (Sweden)

    Ellen Gerhardt

    Full Text Available Heterozygous loss-of-function mutation of the human gene for the mitochondrial protease HtrA2 has been associated with increased risk to develop mitochondrial dysfunction, a process known to contribute to neurodegenerative disorders such as Huntington's disease (HD and Parkinson's disease (PD. Knockout of HtrA2 in mice also leads to mitochondrial dysfunction and to phenotypes that resemble those found in neurodegenerative disorders and, ultimately, lead to death of animals around postnatal day 30. Here, we show that Idebenone, a synthetic antioxidant of the coenzyme Q family, and Resveratrol, a bioactive compound extracted from grapes, are both able to ameliorate this phenotype. Feeding HtrA2 knockout mice with either compound extends lifespan and delays worsening of the motor phenotype. Experiments conducted in cell culture and on brain tissue of mice revealed that each compound has a different mechanism of action. While Idebenone acts by downregulating the integrated stress response, Resveratrol acts by attenuating apoptosis at the level of Bax. These activities can account for the delay in neuronal degeneration in the striata of these mice and illustrate the potential of these compounds as effective therapeutic approaches against neurodegenerative disorders such as HD or PD.

  3. Different Roles of COMT and HTR2A Genotypes in Working Memory Subprocesses.

    Directory of Open Access Journals (Sweden)

    Hirohito M Kondo

    Full Text Available Working memory is linked to the functions of the frontal areas, in which neural activity is mediated by dopaminergic and serotonergic tones. However, there is no consensus regarding how the dopaminergic and serotonergic systems influence working memory subprocesses. The present study used an imaging genetics approach to examine the interaction between neurochemical functions and working memory performance. We focused on functional polymorphisms of the catechol-O-methyltransferase (COMT Val(158Met and serotonin 2A receptor (HTR2A -1438G/A genes, and devised a delayed recognition task to isolate the encoding, retention, and retrieval processes for visual information. The COMT genotypes affected recognition accuracy, whereas the HTR2A genotypes were associated with recognition response times. Activations specifically related to working memory were found in the right frontal and parietal areas, such as the middle frontal gyrus (MFG, inferior frontal gyrus (IFG, anterior cingulate cortex (ACC, and inferior parietal lobule (IPL. MFG and ACC/IPL activations were sensitive to differences between the COMT genotypes and between the HTR2A genotypes, respectively. Structural equation modeling demonstrated that stronger connectivity in the ACC-MFG and ACC-IFG networks is related to better task performance. The behavioral and fMRI results suggest that the dopaminergic and serotonergic systems play different roles in the working memory subprocesses and modulate closer cooperation between lateral and medial frontal activations.

  4. Effect of core design and veneering technique on damage and reliability of Y-TZP-supported crowns.

    Science.gov (United States)

    Guess, Petra C; Bonfante, Estevam A; Silva, Nelson R F A; Coelho, Paulo G; Thompson, Van P

    2013-03-01

    To evaluate the effect of framework design modification and veneering techniques in fatigue reliability and failure modes of veneered Yttria-Stabilized Tetragonal Zirconia Polycrystals (Y-TZP) crowns. A CAD-based mandibular molar crown preparation served as a master die. Y-TZP crown cores (VITA-In-Ceram-YZ, Vita-Zahnfabrik, Bad Säckingen, Germany) in conventional (0.5mm uniform thickness) or anatomically designed fashion (cusp support) were porcelain veneered with either hand-layer (VM9) or pressed (PM9) techniques. Crowns (n=84) were cemented on 30 days aged dentin-like composite dies with resin cement. Crowns were subjected to single load to fracture (n=3 each group) and mouth-motion step-stress fatigue (n=18) by sliding a WC indenter (r=3.18 mm) 0.7 mm buccally on the inner incline surface of the mesio-lingual cusp. Stress-level curves (use level probability lognormal) and reliability (with 2-sided 90% confidence bounds, CB) for completion of a mission of 50.000 cycles at 200 N load were calculated. Fractographic analyses were performed under light-polarized and scanning electron microscopes. Higher reliability for hand-layer veneered conventional core (0.99, CB 0.98-1) was found compared to its counterpart press-veneered (0.50 CB 0.33-65). Framework design modification significantly increased reliability for both veneering techniques (PM9 [0.98 CB 0.87-0.99], VM9 [1.00 CB 0.99-1]) and resulted in reduced veneer porcelain fracture sizes. Main fracture mode observed was veneer porcelain chipping, regardless of framework design and veneering technique. Hand-layer porcelain veneered on conventional core designs presented higher reliability than press-veneered with similar core designs. Anatomic core design modification significantly increased the reliability and resulted in reduced chip size of either veneering techniques. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  5. The mechanical behavior and reliability prediction of the HTR graphite component at various temperature and neutron dose ranges

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Xiang; Yu, Suyuan [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Wang, Haitao, E-mail: wanght@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Li, Chenfeng [Civil and Computational Engineering Centre, College of Engineering, Swansea University, Swansea SA2 8PP (United Kingdom)

    2014-09-15

    Highlights: • The mechanical behavior of graphite component in HTRs under high temperature and neutron irradiation conditions is simulated. • The computational process of mechanical analysis is introduced. • Deformation, stresses and failure probability of the graphite component are obtained and discussed. • Various temperature and neutron dose ranges are selected in order to investigate the effect of in-core conditions on the results. - Abstract: In a pebble-bed high temperature gas-cooled reactor (HTR), nuclear graphite serves as the main structural material of the side reflectors. The reactor core is made up of a large number of graphite bricks. In the normal operation case of the reactor, the maximum temperature of the helium coolant commonly reaches about 750 °C. After around 30 years’ full power operation, the peak value of in-core fast neutron cumulative dose reaches to 1 × 10{sup 22}n cm{sup −2} (EDN). Such high temperature and neutron irradiation strongly impact the behavior of graphite component, causing obvious deformation. The temperature and neutron dose are unevenly distributed inside a graphite brick, resulting in stress concentrations. The deformation and stress concentration can both greatly affect safety and reliability of the graphite component. In addition, most of the graphite properties (such as Young's modulus and coefficient of thermal expansion) change remarkably under high temperature and neutron irradiations. The irradiation-induced creep also plays a very important role during the whole process, and provides a significant impact on the stress accumulation. In order to simulate the behavior of graphite component under various in-core conditions, all of the above factors must be considered carefully. In this paper, the deformation, stress distribution and failure probability of a side graphite component are studied at various temperature points and neutron dose levels. 400 °C, 500 °C, 600 °C and 750 °C are selected

  6. Expression pattern alterations of the serine protease HtrA1 in normal human placental tissues and in gestational trophoblastic diseases.

    Science.gov (United States)

    Marzioni, Daniela; Quaranta, Alexia; Lorenzi, Teresa; Morroni, Manrico; Crescimanno, Caterina; De Nictolis, Michele; Toti, Paolo; Muzzonigro, Giovanni; Baldi, Alfonso; De Luca, Antonio; Castellucci, Mario

    2009-10-01

    HtrA1 is a secreted protein which behaves as a molecular chaperone at low temperatures and as a serine protease at high temperatures. When the placenta escapes the normal growth control mechanisms, which are present during normal pregnancy, it may develop trophoblastic diseases, such as hydatidiform mole and choriocarcinoma. The aim of the study is to investigate the expression of HtrA1 in these gestational trophoblastic diseases and evaluate whether different HtrA1 expression might be associated with increasingly severe forms of disease. We used immunohistochemistry to assess the expression of HtrA1 in normal human placenta, hydatidiform mole (partial and complete) and choriocarcinoma. In addition to that we used the western blotting technique to quantify HtrA1 immunoreaction in normal human placentas. The most striking finding of our investigation is the decrease in immunostaining of this protease with increasing severity of gestational trophoblastic disease. For instance, in partial and complete moles HtrA1 is weakly expressed in the trophoblast. Moreover, absence of immunoreaction for HtrA1 is observable in the choriocarcinoma cells. In conclusion, we suggest that HtrA1 may play an important role in the pathogenesis and progression of hydatidiform moles and choriocarcinomas, and that HtrA1 may play an important role during the normal development of the placenta, as well as in trophoblastic diseases.

  7. Optimized design method for trench-assisted grade-index ring-core fiber with low DMD and large Aeff

    Science.gov (United States)

    Qiao, Xihui; Tu, Jiajing; Long, Keping

    2017-02-01

    We propose a kind of trench-assisted graded-index ring-core fiber (TA-GI-RCF) with a low refractive index rod deployed in the center of the core, which supports three LP modes (LP01, LP11 and LP21) transmission. There are two difficulties about designing TA-GI-RCF, one is to depart LP21 mode from LP02 mode because their effective indices are too close which makes it difficult to realize only three LP modes transmission; the other one is how to make sure these three LP modes reach the receiver end with low differential mode delay (DMD), so that the computation complexity of multi-input multi-output (MIMO) digital signal process (DSP) can be reduced. At first, we realize the separation of LP21 mode and LP02 mode in TA-GI-RCF by enlarging the size of low refractive index rod. We next investigate the influence of the TA-GI-RCF structural parameters on DMD and DMD slope, and find that a graded-index core and a low refractive index rod can flexibly tune the DMD, and a trench can flexibly control the DMD slope. Through optimizing the core parameters, we find that the design region of α is 1.01 2.23 and that of Δ1 is 0.28% 0.46% at r1=30 μm, where α is the profile exponent and Δ1 is the relative refractive index difference between core and cladding. Simulation results show that TA-GI-RCF can achieve the effective area (Aeff) of LP01 mode over 2000 μm2 and the |DMD| between LP01 mode and LP11 mode is DMD over whole C+L band and large Aeff.

  8. Multi-Core Programming Design Patterns: Stream Processing Algorithms for Dynamic Scene Perceptions

    Science.gov (United States)

    2014-05-01

    Tsukuba, Japan ], 142–151, IEEE (2008). [17] Agullo, E., Demmel, J., Dongarra, J., Hadri, B., Kurzak, J., Langou, J., Ltaief, H., Luszczek, P., and Tomov ...Release; Distribution Unlimited. [20] Song, F., Tomov , S., and Dongarra, J., “Enabling and scaling matrix computations on heterogeneous multi- core and

  9. Design of a Brassica rapa core collection for association mapping studies

    NARCIS (Netherlands)

    Jianjun Zhao, Jianjun; Artemyeva, A.; Pino del Carpio, D.; Basnet, R.K.; Zhang, N.; Gao, Jie; Bucher, J.; Wang, Xiaowu; Visser, R.G.F.; Bonnema, A.B.

    2010-01-01

    A Brassica rapa collection of 239 accessions, based on two core collections representing different morphotypes from different geographical origins, is presented and its use for association mapping is illustrated for flowering time. We analyzed phenotypic variation of leaf and seed pod traits, plant

  10. Can Cognitive Writing Models Inform the Design of the Common Core State Standards?

    Science.gov (United States)

    Hayes, John R.; Olinghouse, Natalie G.

    2015-01-01

    In this article, we compare the Common Core State Standards in Writing to the Hayes cognitive model of writing, adapted to describe the performance of young and developing writers. Based on the comparison, we propose the inclusion of standards for motivation, goal setting, writing strategies, and attention by writers to the text they have just…

  11. A model for the design and programming of multi-cores

    NARCIS (Netherlands)

    Jesshope, C.; Grandinetti, L.

    2008-01-01

    This paper describes a machine/programming model for the era of multi-core chips. It is derived from the sequential model but replaces sequential composition with concurrent composition at all levels in the program except at the level where the compiler is able to make deterministic decisions on

  12. Design and optimization of Ag-dielectric core-shell nanostructures for silicon solar cells

    Directory of Open Access Journals (Sweden)

    Feng-Xiang Chen

    2015-09-01

    Full Text Available Metal-dielectric core-shell nanostructures have been proposed as a light trapping scheme for enhancing the optical absorption of silicon solar cells. As a potential application of such enhanced effects, the scattering efficiencies of three core-shell structures (Ag@SiO2, Ag@TiO2, and Ag@ZrO2 are discussed using the Mie Scattering theory. For compatibility with experiment results, the core diameter and shell thickness are limited to 100 and 30 nm, respectively, and a weighted scattering efficiency is introduced to evaluate the scattering abilities of different nanoparticles under the solar spectrum AM 1.5. The simulated results indicate that the shell material and thickness are two key parameters affecting the weighted scattering efficiency. The SiO2 is found to be an unsuitable shell medium because of its low refractive index. However, using the high refractive index mediumTiO2 in Ag@TiO2 nanoparticles, only the thicker shell (30 nm is more beneficial for light scattering. The ZrO2 is an intermediate refractive index material, so Ag@ZrO2 nanoparticles are the most effective core-shell nanostructures in these silicon solar cells applications.

  13. Transformer design principles with applications to core-form power transformers

    CERN Document Server

    Del Vecchio, Robert M; Feeney, Mary-Ellen F

    2001-01-01

    Transformer Design Principles presents the theory of transformer operation and the methods and techniques of designing them. It emphasizes the physical principles and mathematical tools for simulating transformer behavior, including modern computer techniques. The scope of the book includes types of construction, circuit analysis, mechanical aspects of design, high voltage insulation requirements, and cooling design. The authors also address test procedures and reliability methods to assure successful design and discuss the economic analysis of designs. Summarizing material currently scattered

  14. Effective Web Design and Core Communication Issues: The Missing Components in Web-Based Distance Education.

    Science.gov (United States)

    Burch, Randall O.

    2001-01-01

    Discussion of Web-based distance education focuses on communication issues. Highlights include Internet communications; components of a Web site, including site architecture, user interface, information delivery method, and mode of feedback; elements of Web design, including conceptual design, sensory design, and reactive design; and a Web…

  15. A design study of reactor core optimization for direct nuclear heat-to-electricity conversion in a space power reactor

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Hidekazu; Takahashi, Makoto; Shimoda, Hiroshi; Takeoka, Satoshi [Kyoto Univ. (Japan); Nakagawa, Masayuki; Kugo, Teruhiko

    1998-01-01

    To propose a new design concept of a nuclear reactor used in the space, research has been conducted on the conceptual design of a new nuclear reactor on the basis of the following three main concepts: (1) Thermionic generation by thermionic fuel elements (TFE), (2) reactivity control by rotary reflector, and (3) reactor cooling by liquid metal. The outcomes of the research are: (1) A calculation algorithm was derived for obtaining convergent conditions by repeating nuclear characteristic calculation and thermal flow characteristic calculation for the space nuclear reactor. (2) Use of this algorithm and the parametric study established that a space nuclear reactor using 97% enriched uranium nitride as the fuel and lithium as the coolant and having a core with a radius of about 25 cm, a height of about 50 cm and a generation efficiency of about 7% can probably be operated continuously for at least more than ten years at 100 kW only by reactivity control by rotary reflector. (3) A new CAD/CAE system was developed to assist design work to optimize the core characteristics of the space nuclear reactor comprehensively. It is composed of the integrated design support system VINDS using virtual reality and the distributed system WINDS to collaboratively support design work using Internet. (N.H.)

  16. Design of a boiling water reactor core based on an integrated blanket-seed thorium-uranium concept

    Energy Technology Data Exchange (ETDEWEB)

    Nunez-Carrera, Alejandro [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Mor. (Mexico); Comision Nacional de Seguridad Nuclear y Salvaguardias, Dr. Barragan 779, Col. Narvarte, 03020 Mexico, D.F. (Mexico); Francois, Juan Luis [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Mor. (Mexico)]. E-mail: jlfl@fi-b.unam.mx; Martin-del-Campo, Cecilia [Facultad de Ingenieria, Universidad Nacional Autonoma de Mexico, Laboratorio de Analisis en Ingenieria de Reactores Nucleares, Paseo Cuauhnahuac 8532, 62550 Jiutepec, Mor. (Mexico); Espinosa-Paredes, Gilberto [Area de Ingenieria en Recursos Energeticos, Universidad Autonoma Metropolitana, Avenida San Rafael Atlixco 186, Col. Vicentina, 09340 Mexico, D.F. (Mexico)

    2005-04-15

    This paper is concerned with the design of a boiling water reactor (BWR) equilibrium core using thorium as a nuclear material in an integrated blanket-seed (BS) assembly. The integrated BS concept comes from the fact that the blanket and the seed rods are located in the same assembly, and are burned out in a once-through cycle. The idea behind the lattice design is to use the thorium conversion capability in a BWR spectrum, taking advantage of the {sup 233}U build-up. A core design was developed to achieve an equilibrium cycle of 365 effective full power days in a standard BWR with a reload of 104 fuel assemblies designed with an average {sup 235}U enrichment of 7.5 w/o in the seed sub-lattice. The main operating parameters, like power, linear heat generation rate and void distributions were obtained as well as the shutdown margin. It was observed that the analyzed parameters behave like those obtained in a standard BWR. The shutdown margin design criterion was fulfilled by addition of a burnable poison region in the fuel assembly.

  17. Design and analysis of photonic quasi-crystal hollow core fibers

    Science.gov (United States)

    Bahrampour, Abolfazl; Iadicicco, Agostino; Bahrampour, Ali Reza; Campopiano, Stefania; Cutolo, Antonello; Cusano, Andrea

    2013-05-01

    We present a new class of hollow core photonic crystal fibers taking the advantages of quasi-crystals structures. We analyze two structures based on modified 8-fold and 12-fold symmetries and we presente the ability of air guiding propagation having two photonic bandgap in the λ/Λ<1 In this paper bandgap of both structures as well as the behavior of the guided modes via finite element method are investigated.

  18. Design and fuel management of PWR cores to optimize the once-through fuel cycle

    Energy Technology Data Exchange (ETDEWEB)

    Fujita, E.K.; Driscoll, M.J.; Lanning, D.D.

    1978-08-01

    The once-through fuel cycle has been analyzed to see if there are substantial prospects for improved uranium ore utilization in current light water reactors, with a specific focus on pressurized water reactors. The types of changes which have been examined are: (1) re-optimization of fuel pin diameter and lattice pitch, (2) axial power shaping by enrichment gradation in fresh fuel, (3) use of 6-batch cores with semi-annual refueling, (4) use of 6-batch cores with annual refueling, hence greater extended (approximately doubled) burnup, (5) use of radial reflector assemblies, (6) use of internally heterogeneous cores (simple seed/blanket configurations), (7) use of power/temperature coastdown at the end of life to extend burnup, (8) use of metal or diluted oxide fuel, (9) use of thorium, and (10) use of isotopically separated low sigma/sub a/ cladding material. State-of-the-art LWR computational methods, LEOPARD/PDQ-7/FLARE-G, were used to investigate these modifications.

  19. Evaluation of the Effect of Different Ferrule Designs on Fracture Resistance of Maxillary Incisors Restored with Bonded Posts and Cores

    Directory of Open Access Journals (Sweden)

    E. Jalalian

    2010-09-01

    Full Text Available Introduction: In cases of severe hard tissue loss, 2 mm circumferential ferrule is difficult to achieve. So in these cases we should use different ferrule designs.This in vitro study investigated the effect of different ferrule designs on the fractureresistance of teeth restored with bonded post and cores.Materials and Methods: Forty freshly-extracted central incisors were endodontically treated. The teeth were randomly divided into four groups; group 1 were teeth with 2 mm circumferential ferrule above the CEJ, group 2 were teeth with 2 mm ferrule only on the palatal side of the teeth, group 3 consisted of teeth with 2 mm ferrule only on the facial side and group 4 were teeth with 2 mm ferrule on the palatal and facial side of teeth with interproximal concavities.All teeth were restored with fiber posts and composite cores. The specimen was mounted on a universal testing machine and compressive load was applied to the long axis of the specimen until failure occurred.Results: The fracture resistance was 533.79 ± 232.28 in group 1, 634.75± 133.35 in group 2, 828.90 ±118.27 in group 3 and 678.78± 160.20 in group 4. The post hoc analysis showed statistically significant difference between groups 1 and 3 .Conclusions: The results of this in vitro study showed that facial ferrule increases the fracture resistance of endodontically treated teeth restored with bonded post and cores.

  20. SCC500: next-generation infrared imaging camera core products with highly flexible architecture for unique camera designs

    Science.gov (United States)

    Rumbaugh, Roy N.; Grealish, Kevin; Kacir, Tom; Arsenault, Barry; Murphy, Robert H.; Miller, Scott

    2003-09-01

    A new 4th generation MicroIR architecture is introduced as the latest in the highly successful Standard Camera Core (SCC) series by BAE SYSTEMS to offer an infrared imaging engine with greatly reduced size, weight, power, and cost. The advanced SCC500 architecture provides great flexibility in configuration to include multiple resolutions, an industry standard Real Time Operating System (RTOS) for customer specific software application plug-ins, and a highly modular construction for unique physical and interface options. These microbolometer based camera cores offer outstanding and reliable performance over an extended operating temperature range to meet the demanding requirements of real-world environments. A highly integrated lens and shutter is included in the new SCC500 product enabling easy, drop-in camera designs for quick time-to-market product introductions.

  1. Gene structure and expression of serotonin receptor HTR2C in hypothalamic samples from infanticidal and control sows

    Directory of Open Access Journals (Sweden)

    Quilter Claire R

    2012-04-01

    Full Text Available Abstract Background The serotonin pathways have been implicated in behavioural phenotypes in a number of species, including human, rat, mouse, dog and chicken. Components of the pathways, including the receptors, are major targets for drugs used to treat a variety of physiological and psychiatric conditions in humans. In our previous studies we have identified genetic loci potentially contributing to maternal infanticide in pigs, which includes a locus on the porcine X chromosome long arm. The serotonin receptor HTR2C maps to this region, and is therefore an attractive candidate for further study based on its function and its position in the genome. Results In this paper we describe the structure of the major transcripts produced from the porcine HTR2C locus using cDNA prepared from porcine hypothalamic and pooled total brain samples. We have confirmed conservation of sites altered by RNA editing in other mammalian species, and identified polymorphisms in the gene sequence. Finally, we have analysed expression and editing of HTR2C in hypothalamus samples from infanticidal and control animals. Conclusions The results confirm that although the expression of the long transcriptional variant of HTR2C is raised in infanticidal animals, the overall patterns of editing in the hypothalamus are similar between the two states. Sequences associated with the cDNA and genomic structures of HTR2C reported in this paper are deposited in GenBank under accession numbers FR720593, FR720594 and FR744452.

  2. Vibration Characteristics Determined for Stainless Steel Sandwich Panels With a Metal Foam Core for Lightweight Fan Blade Design

    Science.gov (United States)

    Ghosn, Louis J.; Min, James B.; Raj, Sai V.; Lerch, Bradley A.; Holland, Frederic A., Jr.

    2004-01-01

    The goal of this project at the NASA Glenn Research Center is to provide fan materials that are safer, weigh less, and cost less than the currently used titanium alloy or polymer matrix composite fans. The proposed material system is a sandwich fan construction made up of thin solid face sheets and a lightweight metal foam core. The stiffness of the sandwich structure is increased by separating the two face sheets by the foam layer. The resulting structure has a high stiffness and lighter weight in comparison to the solid facesheet material alone. The face sheets carry the applied in-plane and bending loads (ref. 1). The metal foam core must resist the transverse shear and transverse normal loads, as well as keep the facings supported and working as a single unit. Metal foams have ranges of mechanical properties, such as light weight, impact resistance, and vibration suppression (ref. 2), which makes them more suitable for use in lightweight fan structures. Metal foams have been available for decades (refs. 3 and 4), but the difficulties in the original processes and high costs have prevented their widespread use. However, advances in production techniques and cost reduction have created a new interest in this class of materials (ref. 5). The material chosen for the face sheet and the metal foam for this study was the aerospace-grade stainless steel 17-4PH. This steel was chosen because of its attractive mechanical properties and the ease with which it can be made through the powder metallurgy process (ref. 6). The advantages of a metal foam core, in comparison to a typical honeycomb core, are material isotropy and the ease of forming complex geometries, such as fan blades. A section of a 17-4PH sandwich structure is shown in the following photograph. Part of process of designing any blade is to determine the natural frequencies of the particular blade shape. A designer needs to predict the resonance frequencies of a new blade design to properly identify a useful

  3. SISGR - Design and Characterization of Novel Photocatalysts With Core-Shell Nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Zaera, Francisco [Univ. of California, Riverside, CA (United States). Dept. of Chemistry; Bardeen, Christopher J. [Univ. of California, Riverside, CA (United States). Dept. of Chemistry; Yin, Yadong [Univ. of California, Riverside, CA (United States). Dept. of Chemistry

    2017-03-15

    The overall goal of this project has been to develop new a new and novel class of well-characterized nanostructured Metal@TiO2 core-shell and yolk-shell photocatalysts to address two fundamental issues presently limiting this field: (1) the fast recombination of electron-hole pairs once generated by light absorption, and (2) the recombination of H2 and O2 on the metal surface once produced. These model samples are also used to study the fundamentals of the photocatalytic processes.

  4. Evaluation of improved light water reactor core designs. Final progress report, September 1979. LWRCD-20

    Energy Technology Data Exchange (ETDEWEB)

    1979-10-31

    The work conducted under this research project has developed information which supports in all respects the U.S. position evolved under the NASAP/INFCE programs with respect to the near and intermediate term potential for ore conservation in LWRs on the once-through fuel cycle. Moreover, in the even longer term, it has been confirmed that contention by Edlund and others that tight-pitch Pu/UO/sub 2/ PWR cores can achieve conversion ratios which may allow these reactors to provide a competitive energy source far into the ore-scarce post-2000 era.

  5. Helicobacter pylori HtrA: una proteasa universalmente expresada en cepas aisladas alrededor del mundo con potencial terapéutico

    Directory of Open Access Journals (Sweden)

    Francisco Rivas-Traverso

    2017-03-01

    Full Text Available Las proteasas y chaperonas HtrA exhiben un papel importante en las respuestas de control de calidad de las proteínas periplásmicas y de estrés. La inactivación genética de htrA se ha descrito para muchos patógenos bacterianos, sin embargo, en algunos casos, tales como el patógeno gástrico Helicobacter pylori, HtrA escinde el supresor tumor de tipo E-cadherina interfeririendo con el desarrollo de enfermedad gástrica. Aquí, mostramos que el locus del gen htrA está altamente conservada en las cepas en todo el mundo. La presencia de HtrA se confirmó en 992 aislamientos de H. pylori en biopsias gástricas de pacientes infectados. Se demuestra que H. pylori htrA es un gen esencial bifuncional con funciones cruciales intracelulares y extracelulares. Por lo tanto, como se describe aquí el primer patógeno en el que un gen htrA es indispensable, una situación única en el reino bacteriano. Por lo tanto, HtrA se puede considerar un nuevo objetivo prometedor para la terapia anti-bacteriana.

  6. Whole genome sequencing of a dizygotic twin suggests a role for the serotonin receptor HTR7 in autism spectrum disorder.

    Science.gov (United States)

    Helsmoortel, Céline; Swagemakers, Sigrid M A; Vandeweyer, Geert; Stubbs, Andrew P; Palli, Ivo; Mortier, Geert; Kooy, R Frank; van der Spek, Peter J

    2016-12-01

    Whole genome sequencing of a severely affected dizygotic twin with an autism spectrum disorder and intellectual disability revealed a compound heterozygous mutation in the HTR7 gene as the only variation not detected in control databases. Each parent carries one allele of the mutation, which is not present in an unaffected stepsister. The HTR7 gene encodes the 5-HT7 serotonin receptor that is involved in brain development, synaptic transmission, and plasticity. The paternally inherited p.W60C variant is situated at an evolutionary conserved nucleotide and predicted damaging by Polyphen2. A mutation akin to the maternally inherited pV286I mutation has been reported to significantly affect the binding characteristics of the receptor. Therefore, the observed sequence alterations provide a first suggestive link between a genetic abnormality in the HTR7 gene and a neurodevelopmental disorder. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Costs of head-end incineration with respect to Kr separation in the reprocessing of HTR fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Barnert-Wiemer, H.; Boehnert, R.

    1976-07-15

    The C-incinerations and the Kr-separations during head-end incineration in the reprocessing of HTR fuel elements are described. The costs for constructing an operating a head-end incineration of reprocessing capacities with 5,000 to 50,000 MW(e)-HTR power have been determined. The cost estimates are divided into investment and operating costs, further after the fraction of the N/sub 2/-content in the incineration exhaust gas, which strongly affects costs. It appears that, in the case of Kr-separation from the incineration exhaust gas, the investment costs as well as the operating costs of the head-end for N/sub 2/-containing exhaust gas are considerably greater than those for gas without N/sub 2/. The C-incineration of the graphite of the HTR fuel elements should therefore only be performed with influx gas that is free of N/sub 2/.

  8. Staying True to the Core: Designing the Future Academic Library Experience

    Science.gov (United States)

    Bell, Steven J.

    2014-01-01

    In 2014, the practice of user experience design in academic libraries continues to evolve. It is typically applied in the context of interactions with digital interfaces. Some academic librarians are applying user experience approaches more broadly to design both environments and services with human-centered strategies. As the competition for the…

  9. Very High Temperature Reactor (VHTR) Deep Burn Core and Fuel Analysis -- Complete Design Selection for the Pebble Bed Reactor

    Energy Technology Data Exchange (ETDEWEB)

    B. Boer; A. M. Ougouag

    2010-09-01

    The Deep-Burn (DB) concept focuses on the destruction of transuranic nuclides from used light water reactor fuel. These transuranic nuclides are incorporated into TRISO coated fuel particles and used in gas-cooled reactors with the aim of a fractional fuel burnup of 60 to 70% in fissions per initial metal atom (FIMA). This high performance is expected through the use of multiple recirculation passes of the fuel in pebble form without any physical or chemical changes between passes. In particular, the concept does not call for reprocessing of the fuel between passes. In principle, the DB pebble bed concept employs the same reactor designs as the presently envisioned low-enriched uranium core designs, such as the 400 MWth Pebble Bed Modular Reactor (PBMR-400). Although it has been shown in the previous Fiscal Year (2009) that a PuO2 fueled pebble bed reactor concept is viable, achieving a high fuel burnup, while remaining within safety-imposed prescribed operational limits for fuel temperature, power peaking and temperature reactivity feedback coefficients for the entire temperature range, is challenging. The presence of the isotopes 239-Pu, 240-Pu and 241-Pu that have resonances in the thermal energy range significantly modifies the neutron thermal energy spectrum as compared to a ”standard,” UO2-fueled core. Therefore, the DB pebble bed core exhibits a relatively hard neutron energy spectrum. However, regions within the pebble bed that are near the graphite reflectors experience a locally softer spectrum. This can lead to power and temperature peaking in these regions. Furthermore, a shift of the thermal energy spectrum with increasing temperature can lead to increased absorption in the resonances of the fissile Pu isotopes. This can lead to a positive temperature reactivity coefficient for the graphite moderator under certain operating conditions. The effort of this task in FY 2010 has focused on the optimization of the core to maximize the pebble discharge

  10. Design novel dual agonists for treating type-2 diabetes by targeting peroxisome proliferator-activated receptors with core hopping approach.

    Directory of Open Access Journals (Sweden)

    Ying Ma

    Full Text Available Owing to their unique functions in regulating glucose, lipid and cholesterol metabolism, PPARs (peroxisome proliferator-activated receptors have drawn special attention for developing drugs to treat type-2 diabetes. By combining the lipid benefit of PPAR-alpha agonists (such as fibrates with the glycemic advantages of the PPAR-gamma agonists (such as thiazolidinediones, the dual PPAR agonists approach can both improve the metabolic effects and minimize the side effects caused by either agent alone, and hence has become a promising strategy for designing effective drugs against type-2 diabetes. In this study, by means of the powerful "core hopping" and "glide docking" techniques, a novel class of PPAR dual agonists was discovered based on the compound GW409544, a well-known dual agonist for both PPAR-alpha and PPAR-gamma modified from the farglitazar structure. It was observed by molecular dynamics simulations that these novel agonists not only possessed the same function as GW409544 did in activating PPAR-alpha and PPAR-gamma, but also had more favorable conformation for binding to the two receptors. It was further validated by the outcomes of their ADME (absorption, distribution, metabolism, and excretion predictions that the new agonists hold high potential to become drug candidates. Or at the very least, the findings reported here may stimulate new strategy or provide useful insights for discovering more effective dual agonists for treating type-2 diabetes. Since the "core hopping" technique allows for rapidly screening novel cores to help overcome unwanted properties by generating new lead compounds with improved core properties, it has not escaped our notice that the current strategy along with the corresponding computational procedures can also be utilized to find novel and more effective drugs for treating other illnesses.

  11. Effect of two connector designs on the fracture resistance of all-ceramic core materials for fixed dental prostheses.

    Science.gov (United States)

    Plengsombut, Kwansiri; Brewer, Jane D; Monaco, Edward A; Davis, Elaine L

    2009-03-01

    Most all-ceramic fixed dental prostheses (FDPs) fail at the connectors. The purpose of this study was to determine the effect of 2 connector designs on the fracture resistance of core materials used for all-ceramic FDPs. Three materials were tested: (1) heat-pressed lithium disilicate glass ceramic (IPS e.max Press (Press)), (2) milled lithium disilicate glass ceramic (IPS e.max CAD (CAD)), and (3) milled yttrium-stabilized tetragonal zirconia polycrystals (Y-TZP) (IPS e.max ZirCAD (ZirCAD)). Specimens were made into 30 x 4 x 4-mm bars to represent 3-unit FDPs. Two connector designs, round (0.60 +/-0.01-mm radius of curvature) and sharp (0.06 +/-0.001-mm radius of curvature), with a 3.00 +/-0.05-mm cross-section for each connector, were studied (n=5). Each specimen was loaded to fracture in a universal testing machine with a crosshead speed of 0.1 mm/min. Data were analyzed with a 2-way univariate ANOVA and Tukey HSD test (alpha=.05). Mean (SD) failure loads for round connector designs were 684.2 (70.1) N for ZirCAD, 260 (7.8) N for CAD, and 172.9 (35.5) N for Press. Mean (SD) failure loads for sharp connector designs were 386.3 (51.5) N for ZirCAD, 87.9 (7.0) N for CAD, and 125.1 (15.1) N for Press. The 2-way univariate ANOVA indicated statistically significant differences (Pmaterial and connector design, and, also, a significant interaction between material and connector design. Higher maximum failure loads were found for the round connector design when compared to the sharp connector design, for ZirCAD and CAD. However, this difference was not statistically significant for the Press groups. SEM subjective assessment of the fractured specimens revealed that the fracture initiated from the gingival surface (tensile) of the connector toward the pontic (central loading point). Fracture resistance of ceramic core materials is affected by fabrication technique and connector design. Connector design affected fracture resistance of the milled ceramic, but not the

  12. Design tunable materials: Ferroelectric-antiferroelectric composite with core-shell structure

    Science.gov (United States)

    Curecheriu, Lavinia-Petronela; Buscaglia, Maria Teresa; Maglia, Filippo; Anselmi-Tamburini, Umberto; Buscaglia, Vincenzo; Mitoseriu, Liliana

    2014-12-01

    Permittivity, tunability, and ferroelectric properties can be tailored to meet specific requirements for applications by combining ferroelectric (BaTiO3-BT) and antiferroelectric (La0.04Pb0.96Ti0.1Zr0.9O3-PLZT) and by exploiting interdiffusion and grain size effects at nanoscale. The dielectric properties, dc-tunability, and P(E) loops of ferroelectric-antiferroelectric nanostructured composites produced from mechanically mixed powders (PLZT-BT) and from core-shell particles (PLZT@BT) were comparatively analyzed. Interdiffusion accompanied by local composition gradients occurred during sintering of PLZT@BT composites and caused a thermally stable permittivity. Permittivity was reduced below 1000 in both cases (900 for PLZT-BT and 290 for PLZT@BT), while preserving tunability to 1.2-1.4 (E = 40 kV/cm), with a linear field dependence.

  13. Design and Fabrication of Air-core Inductors for Power Conversion

    DEFF Research Database (Denmark)

    Lê Thanh, Hoà; Mizushima, Io; Tang, Peter Torben

    Microelectromechanical systems (MEMS) inductors are used for e.g. RF MEMS and microelectronics. A new application is for power electronics in switched mode power supplies (SMPS). High-performance power inductors, which can be combined with integrated circuits (IC), are required for future power...... supply on chip (PwrSoC) [1]. Examples of PwrSoC applications are power adaptors for LED illumination and the “Internet of Things”. We report an air-core MEMS inductor. Our process is scalable and universal for making inductors with versatile geometries e.g. spiral, solenoid, toroid, and advanced...... inductors that are impossible to make by wire-winding technology. As all process temperatures are kept below 200 ºC, the inductors can be integrated into CMOS wafers by MEMS post processing....

  14. Modulation of mitochondrial function and morphology by interaction of Omi/HtrA2 with the mitochondrial fusion factor OPA1

    Energy Technology Data Exchange (ETDEWEB)

    Kieper, Nicole; Holmstroem, Kira M.; Ciceri, Dalila; Fiesel, Fabienne C. [Center of Neurology and Hertie Institute for Clinical Brain Research, 72076 Tuebingen (Germany); Wolburg, Hartwig [Institute of Pathology, University of Tuebingen, 72076 Tuebingen (Germany); Ziviani, Elena; Whitworth, Alexander J. [Medical Research Council Centre for Developmental and Biomedical Genetics, University of Sheffield, Sheffield S10 2TN (United Kingdom); Martins, L. Miguel [Cell Death Regulation Laboratory, MRC Toxicology Unit, Leicester LE1 9HN (United Kingdom); Kahle, Philipp J., E-mail: philipp.kahle@uni-tuebingen.de [Center of Neurology and Hertie Institute for Clinical Brain Research, 72076 Tuebingen (Germany); Krueger, Rejko, E-mail: rejko.krueger@uni-tuebingen.de [Center of Neurology and Hertie Institute for Clinical Brain Research, 72076 Tuebingen (Germany)

    2010-04-15

    Loss of Omi/HtrA2 function leads to nerve cell loss in mouse models and has been linked to neurodegeneration in Parkinson's and Huntington's disease. Omi/HtrA2 is a serine protease released as a pro-apoptotic factor from the mitochondrial intermembrane space into the cytosol. Under physiological conditions, Omi/HtrA2 is thought to be involved in protection against cellular stress, but the cytological and molecular mechanisms are not clear. Omi/HtrA2 deficiency caused an accumulation of reactive oxygen species and reduced mitochondrial membrane potential. In Omi/HtrA2 knockout mouse embryonic fibroblasts, as well as in Omi/HtrA2 silenced human HeLa cells and Drosophila S2R+ cells, we found elongated mitochondria by live cell imaging. Electron microscopy confirmed the mitochondrial morphology alterations and showed abnormal cristae structure. Examining the levels of proteins involved in mitochondrial fusion, we found a selective up-regulation of more soluble OPA1 protein. Complementation of knockout cells with wild-type Omi/HtrA2 but not with the protease mutant [S306A]Omi/HtrA2 reversed the mitochondrial elongation phenotype and OPA1 alterations. Finally, co-immunoprecipitation showed direct interaction of Omi/HtrA2 with endogenous OPA1. Thus, we show for the first time a direct effect of loss of Omi/HtrA2 on mitochondrial morphology and demonstrate a novel role of this mitochondrial serine protease in the modulation of OPA1. Our results underscore a critical role of impaired mitochondrial dynamics in neurodegenerative disorders.

  15. Comparison of computational performance of GA and PSO optimization techniques when designing similar systems - Typical PWR core case

    Energy Technology Data Exchange (ETDEWEB)

    Souza Lima, Carlos A. [Instituto de Engenharia Nuclear - Divisao de Reatores/PPGIEN, Rua Helio de Almeida 75, Cidade Universitaria - Ilha do Fundao, P.O. Box: 68550 - Zip Code: 21941-972, Rio de Janeiro (Brazil); Instituto Politecnico, Universidade do Estado do Rio de Janeiro, Pos-Graduacao em Modelagem Computacional, Rua Alberto Rangel - s/n, Vila Nova, Nova Friburgo, Zip Code: 28630-050, Nova Friburgo (Brazil); Lapa, Celso Marcelo F.; Pereira, Claudio Marcio do N.A. [Instituto de Engenharia Nuclear - Divisao de Reatores/PPGIEN, Rua Helio de Almeida 75, Cidade Universitaria - Ilha do Fundao, P.O. Box: 68550 - Zip Code: 21941-972, Rio de Janeiro (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores (INCT) (Brazil); Cunha, Joao J. da [Eletronuclear Eletrobras Termonuclear - Gerencia de Analise de Seguranca Nuclear, Rua da Candelaria, 65, 7 andar. Centro, Zip Code: 20091-906, Rio de Janeiro (Brazil); Alvim, Antonio Carlos M. [Universidade Federal do Rio de Janeiro, COPPE/Nuclear, Cidade Universitaria - Ilha do Fundao s/n, P.O.Box 68509 - Zip Code: 21945-970, Rio de Janeiro (Brazil); Instituto Nacional de Ciencia e Tecnologia de Reatores Nucleares Inovadores (INCT) (Brazil)

    2011-06-15

    Research highlights: > Performance of PSO and GA techniques applied to similar system design. > This work uses ANGRA1 (two loop PWR) core as a prototype. > Results indicate that PSO technique is more adequate than GA to solve this kind of problem. - Abstract: This paper compares the performance of two optimization techniques, particle swarm optimization (PSO) and genetic algorithm (GA) applied to the design a typical reduced scale two loop Pressurized Water Reactor (PWR) core, at full power in single phase forced circulation flow. This comparison aims at analyzing the performance in reaching the global optimum, considering that both heuristics are based on population search methods, that is, methods whose population (candidate solution set) evolve from one generation to the next using a combination of deterministic and probabilistic rules. The simulated PWR, similar to ANGRA 1 power plant, was used as a case example to compare the performance of PSO and GA. Results from simulations indicated that PSO is more adequate to solve this kind of problem.

  16. C.N. Cofrentes power up-rate up to 110 %. A challenge for cycle 14 core design

    Energy Technology Data Exchange (ETDEWEB)

    Gomez Bernal, M.I.; Lopez Carbonell, M.T.; Garcia Delgado, L. [Iberdrola, Nuclear Fuel Dept., Madrid (Spain)

    2001-07-01

    C.N.Cofrentes is a GE design BWR reactor with 624 bundles in the core, a rated power of 2894 MWt and it is currently operating Cycle 13 at 104.2 % power. Commercial operation started in 1984 with 12-month cycles at rated power. Both cycle length and thermal power have been increased since then. Power has been up-rated in two steps, first at 102 % in Cycle 4 and later in Cycle 11 at 104.2%. Cycle length has been extended from the original 12-month to the currently 18-month cycles. Next cycle, Cycle 14, will be an 18-month cycle operating at 110 % power. This goal is a challenge for the in-house nuclear design team. Start up for Cycle 14 is planned for the first quarter of 2002. (author)

  17. Design of the Core Stage Inter-Tank Umbilical {CSITU) Compliance Mechanism

    Science.gov (United States)

    Smith, Kurt R.

    2013-01-01

    Project Goals: a) Design the compliance mechanism for the CSITU system to a 30% level -3D models completed in Pro/Engineer -Relevant design analysis b) Must meet all system requirements and establish basis for proceeding with detailed design. Tasks to be completed: A design that meets requirements for the 30% design review, 01/16/2013. Umbilical arms provide commodities to the launch vehicle prior to T-0. Commodities can range anywhere from hydraulics, pneumatics, cryogenic, electrical, ECS, etc ... Umbilicals commonly employ truss structures to deliver commodities to vehicle. Common configurations include: -Tilt-up -Swing Arm -Hose Drape -Drop Arm Umbilical arms will be mounted to Mobile Launch Platform. SLS currently has 9 T-0 umbilical arms. The compliance refers to the ability of the umbilical to adjust to minor changes in vehicle location. The compliance mechanism refers to the mechanism on the ground support equipment {GSE) that compensates for these changes. For the CSITU, these minor changes, or vehicle excursions, can be up to +4 in. Excursions refer to movements of the vehicle caused by wind loads and thermal expansion. It is ideal to have significant vertical compliance so a passive secondary release mechanism may be implemented.

  18. Design and characterization of antimicrobial usnic acid loaded-core/shell magnetic nanoparticles.

    Science.gov (United States)

    Taresco, Vincenzo; Francolini, Iolanda; Padella, Franco; Bellusci, Mariangela; Boni, Adriano; Innocenti, Claudia; Martinelli, Andrea; D'Ilario, Lucio; Piozzi, Antonella

    2015-01-01

    The application of magnetic nanoparticles (MNPs) in medicine is considered much promising especially because they can be handled and directed to specific body sites by external magnetic fields. MNPs have been investigated in magnetic resonance imaging, hyperthermia and drug targeting. In this study, properly functionalized core/shell MNPs with antimicrobial properties were developed to be used for the prevention and treatment of medical device-related infections. Particularly, surface-engineered manganese iron oxide MNPs, produced by a micro-emulsion method, were coated with two different polymers and loaded with usnic acid (UA), a dibenzofuran natural extract possessing antimicrobial activity. Between the two polymer coatings, the one based on an intrinsically antimicrobial cationic polyacrylamide (pAcDED) resulted to be able to provide MNPs with proper magnetic properties and basic groups for UA loading. Thanks to the establishment of acid-base interactions, pAcDED-coated MNPs were able to load and release significant drug amounts resulting in good antimicrobial properties versus Staphylococcus epidermidis (MIC = 0.1 mg/mL). The use of pAcDED having intrinsic antimicrobial activity as MNP coating in combination with UA likely contributed to obtain an enhanced antimicrobial effect. The developed drug-loaded MNPs could be injected in the patient soon after device implantation to prevent biofilm formation, or, later, in presence of signs of infection to treat the biofilm grown on the device surfaces. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. The passive system for reflooding of the VVER reactor core from the second-stage hydro-accumulators: design and basic design solutions

    Energy Technology Data Exchange (ETDEWEB)

    Alexandr D Efanov; Sergey G Kalyakin; Andrey V Morozov; Oleg V Remizov [State Scientific Center of Russian Federation - Institute for Physics and Power Engineering by A.I. Leypunsky, IPPE, 1, Bondarenko sq., Obninsk, 249030 (Russian Federation); Vladimir M Berkovich; Victor N Krushelnitskiy; Vladimir G Peresadko [FSUE Atomenergoproekt, B-5, 1 bldg.7, Bakuninskaya, 107005, Moscow (Russian Federation); Yuri G Dragunov; Alexey K Podshibyakin; Sergey I Zaitcev [FSUE OKB Gidropress, 21, Ordzhonikidze street, 142103 Podolsk (Russian Federation)

    2005-07-01

    Full text of publication follows: The fundamental difference in the safety assurance of the operating NPPs and those under design implies that the safety in the existing NPPs is achieved by energy-dependent (active) systems and depends on the proficiency of attending personnel. To provide safety, the new NPP designs use the physical processes proceeding in the facility without power supply; and they are unaffected by human errors. As to the safety level, the design of the new generation nuclear power plant NPP-92 relates to the class of the improved NPPs; and it applies a principle of diversity in the structure of systems responsible for critical safety functions. In accordance with the above-mentioned safety concept, the design development required a complex of experimental investigations and numerical modeling to be conducted. Among the passive safety systems of the NPP with RP-392 is the system of the second stage hydro-accumulators (GE-2). The system of the second-stage hydro-accumulators consists of four groups of hydro-accumulating tanks with a total coolant volume of 960 m{sup 3}. The system is intended for the core flooding with coolant during 24 hours. In each group of the hydro-accumulators, the graded coolant flowrate is provided, which depends on residual heat in the reactor. The special check valves are tuned to open at the pressure drop in the circuit below 1.5 MPa. The paper presents the thermalhydraulic substantiation of the serviceability of the second-stage hydro-accumulators system for passive heat removal from the VVER reactor core and the basic design solutions on the GE-2 system. (authors)

  20. Designing and managing your research project: core skills for social and health research

    National Research Council Canada - National Science Library

    Thomas, David R; Hodges, Ian

    2010-01-01

    ... for Social and Health Research David R. Thomas and Ian D. Hodges© David R. Thomas and Ian D. Hodges 2010 First published 2010 Apart from any fair dealing for the purposes of research or private study, or criticism or review, as permitted under the Copyright, Designs and Patents Act, 1988, this publication may be reproduced, stored or transmitted in any ...

  1. GABA A receptor π subunit promotes apoptosis of HTR-8/SVneo trophoblastic cells: Implications in preeclampsia.

    Science.gov (United States)

    Lu, Junjie; Zhang, Qian; Tan, Dongmei; Luo, Wenping; Zhao, Hai; Ma, Jing; Liang, Hao; Tan, Yi

    2016-07-01

    Gamma-aminobutyric acid (GABA) functions primarily as an inhibitory neurotransmitter through its receptors in the mature central nervous system. The GABA type A receptor π subunit (GABRP) has been identified in the tissues of the reproductive system, particularly in the uterus. In addition, we have previously detected GABRP expression in both human and mouse placentas. To examine the role of GABRP in trophoblastic cell invasion, we constructed a pIRES2-GABRP-EGFP plasmid which was used for the transfection of a human placental cell line derived from first trimester extravillous trophoblasts (HTR-8/SVneo). The number of invaded cells was decreased by GABRP overexpression. Notably, the decrease in the invasive cell number may be due to the increased apoptosis of the HTR-8/SVneo cells following GABRP transfection, which was further confirmed by flow cytometry, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. Based on the increased apoptosis of trophoblastic cells in pregnancies complicated by preeclampsia (PE) and the fact that GABRP promotes the apoptosis of trophoblastic cells, we hypothesized that GABRP expression is increased in the placental tissues from patients with PE compared with that in the normal groups and this hypothesis was confirmed by RT-qPCR and immunohistochemical analysis. Taken together, these findings imply that GABRP plays an important role in placentation and this pathway may be a promising molecular target for the development of novel therapeutic strategies for PE.

  2. Chlamydia Serine Protease Inhibitor, targeting HtrA, as a New Treatment for Koala Chlamydia infection

    Science.gov (United States)

    Lawrence, Amba; Fraser, Tamieka; Gillett, Amber; Tyndall, Joel D. A.; Timms, Peter; Polkinghorne, Adam; Huston, Wilhelmina M.

    2016-01-01

    The koala, an iconic marsupial native to Australia, is a threatened species in many parts of the country. One major factor in the decline is disease caused by infection with Chlamydia. Current therapeutic strategies to treat chlamydiosis in the koala are limited. This study examines the effectiveness of an inhibitor, JO146, which targets the HtrA serine protease for treatment of C. pecorum and C. pneumoniae in vitro and ex vivo with the aim of developing a novel therapeutic for koala Chlamydia infections. Clinical isolates from koalas were examined for their susceptibility to JO146. In vitro studies demonstrated that treatment with JO146 during the mid-replicative phase of C. pecorum or C. pneumoniae infections resulted in a significant loss of infectious progeny. Ex vivo primary koala tissue cultures were used to demonstrate the efficacy of JO146 and the non-toxic nature of this compound on peripheral blood mononuclear cells and primary cell lines established from koala tissues collected at necropsy. Our results suggest that inhibition of the serine protease HtrA could be a novel treatment strategy for chlamydiosis in koalas. PMID:27530689

  3. Analysis of Seismic Soil-Structure Interaction for a Nuclear Power Plant (HTR-10

    Directory of Open Access Journals (Sweden)

    Xiaoxin Wang

    2017-01-01

    Full Text Available The response of nuclear power plants (NPPs to seismic events is affected by soil-structure interactions (SSI. In the present paper, a finite element (FE model with transmitting boundaries is used to analyse the SSI effect on the response of NPP buildings subjected to vertically incident seismic excitation. Analysis parameters that affect the accuracy of the calculations, including the dimension of the domain and artificial boundary types, are investigated through a set of models. A numerical SSI analysis for the 10 MW High Temperature Gas Cooled Test Reactor (HTR-10 under seismic excitation was carried out using the developed model. The floor response spectra (FRS produced by the SSI analysis are compared with a fixed-base model to investigate the SSI effect on the dynamic response of the reactor building. The results show that the FRS at foundation level are reduced and those at higher floor levels are altered significantly when taking SSI into account. The peak frequencies of the FRS are reduced due to the SSI, whereas the acceleration at high floor levels is increased at a certain frequency range. The seismic response of the primary system components, however, is reduced by the analysed SSI for the HTR-10 on the current soil site.

  4. Formal and Informal Methods for Multi-Core Design Space Exploration

    Directory of Open Access Journals (Sweden)

    Jean-Francois Kempf

    2014-06-01

    Full Text Available We propose a tool-supported methodology for design-space exploration for embedded systems. It provides means to define high-level models of applications and multi-processor architectures and evaluate the performance of different deployment (mapping, scheduling strategies while taking uncertainty into account. We argue that this extension of the scope of formal verification is important for the viability of the domain.

  5. The performance of 3500 MWth homogeneous and heterogeneous metal fueled core designs

    Energy Technology Data Exchange (ETDEWEB)

    Turski, R.; Yang, Shi-tien

    1987-11-01

    Performance parameters are calculated for a representative 3500 MWth homogeneous and a heterogeneous metal fueled reactor design. The equilibrium cycle neutronic characteristics, safety coefficients, control system requirements, and control rod worths are evaluated. The thermal-hydraulic characteristics for both configurations are also compared. The heavy metal fuel loading requirements and neutronic performance characteristics are also evaluated for the uranium startup option. 14 refs., 14 figs., 20 tabs.

  6. The NG2 Proteoglycan Protects Oligodendrocyte Precursor Cells against Oxidative Stress via Interaction with OMI/HtrA2.

    Science.gov (United States)

    Maus, Frank; Sakry, Dominik; Binamé, Fabien; Karram, Khalad; Rajalingam, Krishnaraj; Watts, Colin; Heywood, Richard; Krüger, Rejko; Stegmüller, Judith; Werner, Hauke B; Nave, Klaus-Armin; Krämer-Albers, Eva-Maria; Trotter, Jacqueline

    2015-01-01

    The NG2 proteoglycan is characteristically expressed by oligodendrocyte progenitor cells (OPC) and also by aggressive brain tumours highly resistant to chemo- and radiation therapy. Oligodendrocyte-lineage cells are particularly sensitive to stress resulting in cell death in white matter after hypoxic or ischemic insults of premature infants and destruction of OPC in some types of Multiple Sclerosis lesions. Here we show that the NG2 proteoglycan binds OMI/HtrA2, a mitochondrial serine protease which is released from damaged mitochondria into the cytosol in response to stress. In the cytosol, OMI/HtrA2 initiates apoptosis by proteolytic degradation of anti-apoptotic factors. OPC in which NG2 has been downregulated by siRNA, or OPC from the NG2-knockout mouse show an increased sensitivity to oxidative stress evidenced by increased cell death. The proapoptotic protease activity of OMI/HtrA2 in the cytosol can be reduced by the interaction with NG2. Human glioma expressing high levels of NG2 are less sensitive to oxidative stress than those with lower NG2 expression and reducing NG2 expression by siRNA increases cell death in response to oxidative stress. Binding of NG2 to OMI/HtrA2 may thus help protect cells against oxidative stress-induced cell death. This interaction is likely to contribute to the high chemo- and radioresistance of glioma.

  7. Serotonin receptor gene (HTR2A) T102C polymorphism modulates individuals' perspective taking ability and autistic-like traits.

    Science.gov (United States)

    Gong, Pingyuan; Liu, Jinting; Blue, Philip R; Li, She; Zhou, Xiaolin

    2015-01-01

    Previous studies have indicated that empathic traits, such as perspective taking, are associated with the levels of serotonin in the brain and with autism spectrum conditions. Inspired by the finding that the serotonin receptor 2A gene (HTR2A) modulates the availability of serotonin, this study investigated to what extent HTR2A modulates individuals' perspective taking ability and autistic-like traits. To examine the associations of the functional HTR2A polymorphism T102C (rs6313) with individuals' perspective taking abilities and autistic-like traits, we differentiated individuals according to this polymorphism and measured empathic and autistic-like traits with Interpersonal Reactivity Index (IRI) and Autism-Spectrum Quotient (AQ) scale in 523 Chinese people. The results indicated that this polymorphism was significantly associated with the scores on Perspective Taking and Personal Distress subscales of IRI, and Communication subscale of AQ. Individuals with a greater number of the C alleles were less likely to spontaneously adopt the point of view of others, more likely to be anxious when observing the pain endured by others, and more likely to have communication problems. Moreover, the genotype effect on communication problems was mediated by individuals' perspective taking ability. These findings provide evidence that the HTR2A T102C polymorphism is a predictor of individual differences in empathic and autistic-like traits and highlight the role of the gene in the connection between perspective taking and autistic-like traits.

  8. Serotonin receptor gene (HTR2A) T102C polymorphism modulates individuals’ perspective taking ability and autistic-like traits

    Science.gov (United States)

    Gong, Pingyuan; Liu, Jinting; Blue, Philip R.; Li, She; Zhou, Xiaolin

    2015-01-01

    Previous studies have indicated that empathic traits, such as perspective taking, are associated with the levels of serotonin in the brain and with autism spectrum conditions. Inspired by the finding that the serotonin receptor 2A gene (HTR2A) modulates the availability of serotonin, this study investigated to what extent HTR2A modulates individuals’ perspective taking ability and autistic-like traits. To examine the associations of the functional HTR2A polymorphism T102C (rs6313) with individuals’ perspective taking abilities and autistic-like traits, we differentiated individuals according to this polymorphism and measured empathic and autistic-like traits with Interpersonal Reactivity Index (IRI) and Autism-Spectrum Quotient (AQ) scale in 523 Chinese people. The results indicated that this polymorphism was significantly associated with the scores on Perspective Taking and Personal Distress subscales of IRI, and Communication subscale of AQ. Individuals with a greater number of the C alleles were less likely to spontaneously adopt the point of view of others, more likely to be anxious when observing the pain endured by others, and more likely to have communication problems. Moreover, the genotype effect on communication problems was mediated by individuals’ perspective taking ability. These findings provide evidence that the HTR2A T102C polymorphism is a predictor of individual differences in empathic and autistic-like traits and highlight the role of the gene in the connection between perspective taking and autistic-like traits. PMID:26557070

  9. Serotonin receptor gene (HTR2A T102C polymorphism modulates individuals’ perspective taking ability and autistic-like traits

    Directory of Open Access Journals (Sweden)

    Pingyuan eGong

    2015-10-01

    Full Text Available Previous studies have indicated that empathic traits, such as perspective taking, are associated with the levels of serotonin in the brain and with autism spectrum conditions. Inspired by the finding that the serotonin receptor 2A gene (HTR2A modulates the availability of serotonin, this study investigated to what extent HTR2A modulates individuals’ perspective taking ability and autistic-like traits. To examine the associations of the functional HTR2A polymorphism T102C (rs6313 with individuals’ perspective taking ability and autistic-like traits, we differentiated individuals according to this polymorphism and measured empathic and autistic-like traits with Interpersonal Reactivity Index (IRI and Autism-Spectrum Quotient (AQ scale in 523 Chinese people. The results indicated that this polymorphism was significantly associated with the scores on Perspective Taking and Personal Distress subscales of IRI, and Communication subscale of AQ. Individuals with a greater number of the C alleles were less likely to spontaneously adopt the point of view of others, more likely to be anxious when observing the pain endured by others, and more likely to have communication problems. Moreover, the genotype effect on communication problems was mediated by individuals’ perspective taking ability. These findings provide evidence that the HTR2A T102C polymorphism is a predictor of individual differences in empathic and autistic-like traits and highlight the role of the gene in the connection between perspective taking and autistic-like traits.

  10. PWR core design with Metal Matrix Micro-encapsulated (M3) fuel

    OpenAIRE

    Fratoni, M; Terrani, KA

    2017-01-01

    © 2017 Elsevier Ltd Metal Matrix Micro-encapsulated (M3) fuel consists of TRISO coated fuel particles directly dispersed in a matrix of zirconium metal to form a solid rod. In this integral fuel concept the cladding tube and the failure mechanisms associated with it have been eliminated; therefore, M3 fuel, compared to existing fuel designs, is expected to provide greatly improved operational performance. The main challenge to the deployment of M3 fuels is the low heavy metal load. This needs...

  11. Experiences on fuel and core design in Cofrentes nuclear power plants; Experiencias de diseno de combustible y de nucleo en CN Cofrentes

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, L.; Lopez, M. T.

    2001-07-01

    The electricity market deregulation in Spain is increasing the need for innovations and cost reductions in nuclear power production. In the fuel area this can be achieved by improving fuel and core designs and by introducing vendors competition. IBERDROLA has made significant efforts towards the introduction of mixed cores with fuel from different vendors at Cofrentes Nuclear Power Plant using the in-house nuclear design methodology (GIRALDA methodology) for design and licensing. The codes used in this methodology are independent from fuel vendors codes, thus permitting independent comparison of different types of fuel bundles. Commercial operation started in C. N. Cofrentes in 1984 with 12-month cycles at rated power. Both cycle length and thermal power have been increased, an the plant is currently operating cycle 13 at 104.2% power. There are plants to further update to 110% in cycle 14. The evolution in bundle geometrical design together with the vendors diversification program has resulted in mixed cores with bundles from the same supplier up to cycle 11, and from different suppliers thereafter. The experience acquired in nuclear design is reviewed in this paper. In particular, the following items are addressed, the following items are addressed: better core understanding, cooperation with fuel vendors; update of code versions; design margins; response to a fuel failure in cycle 12; comparison of core follow and design, auxiliary tools based on the design codes. The application of the GIRALDA methodology to the design and licensing of Cofrentes fuel loadings is giving satisfactory results. On the one hand, this methodology is showing its capability to adequately reproduce the core performance in cycles 12 and 13. On the other hand, the competition between fuel suppliers has led to fuel deregulated market. GIRALDA represents a continuous challenge for IBERDROLA and the main axis of its nuclear fuel management. (Author)

  12. Design and synthesis of novel ROR inverse agonists with a dibenzosilole scaffold as a hydrophobic core structure.

    Science.gov (United States)

    Toyama, Hirozumi; Nakamura, Masaharu; Hashimoto, Yuichi; Fujii, Shinya

    2015-07-01

    Molecular structure calculations indicated that the dibenzosilole skeleton could be well superposed on phenanthridinone, which is a structural component of ligands of retinoic acid receptor-related orphan receptors (RORs). Therefore, we designed, synthesized and biologically evaluated a series of novel ROR ligands based on the dibenzosilole scaffold as a hydrophobic core structure. Dibenzosilole derivatives bearing a hexafluoro-2-hydroxypropyl group on the benzene ring exhibited significant ROR-inhibitory activity, comparable to that of the lead phenanthridinone derivative 5. Our results indicate that the dibenzosilole skeleton would be a useful scaffold for developing novel biologically active compounds, and that cis-amide structure can be replaced by an alkylsilyl functionality. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Near-zero dispersion flattened, low-loss porous-core waveguide design for terahertz signal transmission

    Science.gov (United States)

    Sultana, Jakeya; Islam, Md. Saiful; Atai, Javid; Islam, Muhammad Rakibul; Abbott, Derek

    2017-07-01

    We demonstrate a photonic crystal fiber with near-zero flattened dispersion, ultralower effective material loss (EML), and negligible confinement loss for a broad spectrum range. The use of cyclic olefin copolymer Topas with improved core confinement significantly reduces the loss characteristics and the use of higher air filling fraction results in flat dispersion characteristics. The properties such as dispersion, EML, confinement loss, modal effective area, and single-mode operation of the fiber have been investigated using the full-vector finite element method with the perfectly matched layer absorbing boundary conditions. The practical implementation of the proposed fiber is achievable with existing fabrication techniques as only circular-shaped air holes have been used to design the waveguide. Thus, it is expected that the proposed terahertz waveguide can potentially be used for flexible and efficient transmission of terahertz waves.

  14. Towards spatial isolation design in a multi-core real-time kernel targeting safety-critical applications

    DEFF Research Database (Denmark)

    Li, Gang; Top, Søren

    2013-01-01

    In mixed-criticality systems, applications naturally have different safety criticality levels. Partitioning technology is usually used to enable the integration of such mixed criticality applications upon one platform, aiming at reducing hardware, power consumption and especially certification co...... and software can easily achieve this isolation. At last, the spatial isolation is evaluated using a statistical sampling method and its performance is tested in terms of task switch, system call and footprint........ According to formulated isolation requirements, a simple partitioning multi-core hardware architecture is proposed using SoC and memory protection units, and the kernel is extended to support spatial isolation between the kernel and applications as well as between applications. Combined design of hardware...

  15. ITER Core Imaging X-Ray Spectrometer Conceptual Design and Performance Assessment - Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Beiersdorfer, P; Wen, J; Dunn, J; Morris, K

    2011-01-02

    During Phase 2 of our study of the CIXS conceptual design we have tackled additional important issues that are unique to the ITER environment. These include the thermal control of the crystal and detector enclosures located in an environment with a 100-250 C ambient temperature, tritium containment, and the range of crystal and detector movement based on the need for spectral adjustments and the desire to make measurements of colder plasmas. In addressing these issues we have selected a ''Dewar''-type enclosure for the crystals and detectors. Applying realistic view factors for radiant heat and making allowance for conduction we have made engineering studies of this enclosure and showed that the cooling requirements can be solved and the temperature can be kept sufficiently constant without compromising the specification parameters of the CIXS. We have chosen a minimum 3 mm combined thickness of the six beryllium windows needed in a Dewar-type enclosure and showed that a single window of 0.5 mm thickness satisfies tritium containment requirements. For measuring the temperature in cooler ITER plasmas, we have chosen to use the K-shell lines of Fe24+. Iron is the preferred choice because its radiation can be analyzed with the identical CIXS settings used for analyzing the tungsten radiation, i.e., essentially no adjustments besides a simple crystal rotation need to be made. We have, however, included an xy{theta}-drive motor arrangement in our design for fine adjustments and full rotation of the crystal mounts.

  16. Design and in-core fuel management of reload fuel elements for reactors made by other manufacturers. Auslegung und Einsatzplanung von Nachlade-Brennelementen fuer Reaktoren anderer Hersteller

    Energy Technology Data Exchange (ETDEWEB)

    Neufert, A.; Urban, P.

    1990-12-01

    By the end of 1990 Siemens had performed fuel element designs and in-core fuel management for 94 operating cycles in 27 pressurized and boiling water reactors of other manufacturers. Together with the client different fuel element designs are developed and proof is furnished of the reactor physics compatibility of different fuel elements from various producers, and of plant safety. (DG).

  17. Design of inhibitors of the HIV-1 integrase core domain using virtual screening.

    Science.gov (United States)

    Regon, Preetom; Gogoi, Dhrubajyoti; Rai, Ashok Kumar; Bordoloi, Manabjyoti; Bezbaruah, Rajib Lochan

    2014-01-01

    Acquired immunodeficiency syndrome (AIDS) is a disease of the human immune system caused by the human immunodeficiency virus (HIV). The integrase (IN) enzyme of HIV interacts with several cellular and viral proteins during the integration process. Thus, it represents an appropriate target for antiretroviral drugs (ARVs). We performed virtual screening of database compounds and designed analogues using Elvitegravir (EVG) as a standard compound. The 378 screened compounds were retrieved from ZINC, ChemSpider, PubChem, and ChemBank Chemical Databases based on chemical similarity and literature searches related to the structure of EVG. The Physiochemical properties, Bioactivity, Toxicity and Absorption, Distribution, Metabolism and Excretion of Molecules (ADME) of these compounds were predicted and docking Experiments were conducted using Molegro Virtual Docker software. The docking and ADME suggested very significant results in regard to EVG. The MolDock and Rerank scores were used to analyze the results. The compounds ZINC26507991 (-84.22), Analogue 9 (-68.49), ZINC20731658 (-66.79), ZINC00210363 (-43.44) showed better binding orientation with IN receptor model with respect to EVG (182.52). The ZINC26507991 has showed significant ADME result.

  18. Design And Implementation of Low Area/Power Elliptic Curve Digital Signature Hardware Core

    Directory of Open Access Journals (Sweden)

    Anissa Sghaier

    2017-06-01

    Full Text Available The Elliptic Curve Digital Signature Algorithm(ECDSA is the analog to the Digital Signature Algorithm(DSA. Based on the elliptic curve, which uses a small key compared to the others public-key algorithms, ECDSA is the most suitable scheme for environments where processor power and storage are limited. This paper focuses on the hardware implementation of the ECDSA over elliptic curveswith the 163-bit key length recommended by the NIST (National Institute of Standards and Technology. It offers two services: signature generation and signature verification. The proposed processor integrates an ECC IP, a Secure Hash Standard 2 IP (SHA-2 Ip and Random Number Generator IP (RNG IP. Thus, all IPs will be optimized, and different types of RNG will be implemented in order to choose the most appropriate one. A co-simulation was done to verify the ECDSA processor using MATLAB Software. All modules were implemented on a Xilinx Virtex 5 ML 50 FPGA platform; they require respectively 9670 slices, 2530 slices and 18,504 slices. FPGA implementations represent generally the first step for obtaining faster ASIC implementations. Further, the proposed design was also implemented on an ASIC CMOS 45-nm technology; it requires a 0.257 mm2 area cell achieving a maximum frequency of 532 MHz and consumes 63.444 (mW. Furthermore, in this paper, we analyze the security of our proposed ECDSA processor against the no correctness check for input points and restart attacks.

  19. On-site methanol production plant from natural gas with modular HTR

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Eiji; Ohashi, Kazutaka; Hayakawa, Hitoshi [Fuji Electric Co. Ltd., Kawasaki, Kanagawa (Japan)

    1997-11-01

    The consumption of natural gas has been increasing year by year due to its relatively low level of CO{sub 2} emissions and low cost. All of the natural gas consumed in Japan is imported from foreign countries in the form of liquid natural gas (LNG). Therefore, liquefaction, transportation and storage equipment costs are large. On the other hand, handling methanol is as easy as handling oil. If a plant for producing methanol from natural gas is sited near a natural gas field, transportation and storage costs are expected to be significantly lower than such costs for LNG production. From the above viewpoint, the concept of an on-site methanol production plant with a modular HTR (High Temperature Reactor) was studied. (author)

  20. Preliminary Thermo-hydraulic Core Design Analysis of Korea Advanced Nuclear Thermal Engine Rocket for Space Application

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Seung Hyun; Lee, Jeong Ik; Chang, Soon Heung [Korea Advanced Institute of Science and Technology, Daejeon (Korea, Republic of)

    2014-05-15

    {sub th} power and electricity generation with 100 kW{sub th} idle power. Consequently, KANUTER has the characteristics of a compact and lightweight system, excellent propellant efficiency, bimodal capability, and mission versatility as indicated in the reference design parameters. This thermo-hydraulic design analysis was carried out to estimate the optimum FWT of the unique SLHC fuel design in the core and thereby the maximum rocket performance. The FWT affects the mechanical strength of the SLHC fuel assembly as well as the thermo-hydraulic capability mainly depending on the heat transfer area of fuel. The thicker fuel wafer is mechanically strong with low pressure drop, while the thinner fuel wafer is thermally robust with less mechanical strength and higher shear stress in the core.

  1. Optical designs of reflection and refraction collection optics for a JT-60SA core Thomson scattering system

    Science.gov (United States)

    Tojo, H.; Hatae, T.; Hamano, T.; Sakuma, T.; Itami, K.

    2013-09-01

    Collection optics for core measurements in a JT-60SA Thomson scattering system were designed. The collection optics will be installed in a limited space and have a wide field of view and wide wavelength range. Two types of the optics are therefore suggested: refraction and reflection types. The reflection system, with a large primary mirror, avoids large chromatic aberrations. Because the size limit of the primary mirror and vignetting due to the secondary mirror affect the total collection throughput, conditions that provide the high throughput are found through an optimization. A refraction system with four lenses forming an Ernostar system is also employed. The use of high-refractive-index glass materials enhances the freedom of the lens curvatures, resulting in suppression of the spherical and coma aberration. Moreover, sufficient throughput can be achieved, even with smaller lenses than that of a previous design given in [H. Tojo, T. Hatae, T. Sakuma, T. Hamano, K. Itami, Y. Aida, S. Suitoh, and D. Fujie, Rev. Sci. Instrum. 81, 10D539 (2010)]. The optical resolutions of the reflection and refraction systems are both sufficient for understanding the spatial structures in plasma. In particular, the spot sizes at the image of the optics are evaluated as {˜}0.3 mm and {˜}0.4 mm, respectively. The throughput for the two systems, including the pupil size and transmissivity, are also compared. The results show that good measurement accuracy (temperatures ({refraction system.

  2. Helicobacter pylori HtrA: una proteasa universalmente expresada en cepas aisladas alrededor del mundo con potencial terapéutico

    OpenAIRE

    Francisco Rivas-Traverso

    2017-01-01

    Las proteasas y chaperonas HtrA exhiben un papel importante en las respuestas de control de calidad de las proteínas periplásmicas y de estrés. La inactivación genética de htrA se ha descrito para muchos patógenos bacterianos, sin embargo, en algunos casos, tales como el patógeno gástrico Helicobacter pylori, HtrA escinde el supresor tumor de tipo E-cadherina interfeririendo con el desarrollo de enfermedad gástrica. Aquí, mostramos que el locus del gen htrA está altamente conservada en las ce...

  3. Regulation of HtrA2 on WT1 gene expression under imatinib stimulation and its effects on the cell biology of K562 cells.

    Science.gov (United States)

    Zhang, Lixia; Li, Yan; Li, Xiaoyan; Zhang, Qing; Qiu, Shaowei; Zhang, Qi; Wang, Min; Xing, Haiyan; Rao, Qing; Tian, Zheng; Tang, Kejing; Wang, Jianxiang; Mi, Yingchang

    2017-09-01

    The aim of the present study was to investigate the regulation of Wilms Tumor 1 (WT1) by serine protease high-temperature requirement protein A2 (HtrA2), a member of the Htr family, in K562 cells. In addition, the study aimed to observe the effect of this regulation on cell biological functions and its associated mechanisms. Expression of WT1 and HtrA2 mRNA, and proteins following imatinib and the HtrA2 inhibitor 5-[5-(2-nitrophenyl) furfuryl iodine]-1, 3-diphenyl-2-thiobarbituric acid (UCF-101) treatment was detected with reverse transcription-quantitative polymerase chain reaction and western blot analysis. Subsequent to treatment with drugs and UCF-101, the proliferative function of K562 cells was detected using MTT assays, and the rate of apoptosis was detected using Annexin V with propidium iodide flow cytometry in K562 cells. The protein levels in the signaling pathway were analyzed using western blotting following treatment with imatinib and UCF-101. In K562 cells, imatinib treatment activated HtrA2 gene at a transcription level, while the WT1 gene was simultaneously downregulated. Following HtrA2 inhibitor (UCF-101) treatment, the downregulation of WT1 increased gradually. At the protein level, imatinib induced the increase in HtrA2 protein level and concomitantly downregulated WT1 protein level. Subsequent to HtrA2 inhibition by UCF-101, the WT1 protein level decreased temporarily, but eventually increased. Imatinib induced apoptosis in K562 cells, but this effect was attenuated by the HtrA2 inhibitor UCF-101, resulting in the upregulation of the WT1 protein level. However; UCF-101 did not markedly change the proliferation inhibition caused by imatinib. Imatinib activated the p38 mitogen activated protein kinase (p38 MAPK) signaling pathway in K562 cells, and UCF-101 affected the activation of imatinib in the p38 MAPK signaling pathway. Imatinib inhibited the extracellular signal-related kinase (ERK1/2) pathway markedly and persistently, but UCF-101

  4. A INFLUÊNCIA DAS CORES NA USABILIDADE DE INTERFACES ATRAVÉS DO DESIGN CENTRADO NO COMPORTAMENTO CULTURAL DO USUÁRIO

    OpenAIRE

    Kulpa, Cínthia Costa; Pinheiro, Eluza Toledo; Silva, Régio Pierre da

    2011-01-01

    Este artigo busca uma relação entre a influência das cores na usabilidade de interfaces através do design centrado no comportamento cultural do usuário. Para isto, se fez referência na bibliografia de design centrado no usuário, suas relações com as interfaces, interação humano-computador, definições de usabilidade e principalmente definições e características das cores. Foi necessário pesquisar informações sobre o comportamento cultural do usuário e como se relacionam estes aspectos culturai...

  5. Assignment of a human homolog of the mouse Htr3 receptor gene to chromosome 11q23.1-q23.2

    Energy Technology Data Exchange (ETDEWEB)

    Weiss, B.; Mertz, A.; Rappold, G. [Univ. of Heidelberg (Germany)] [and others

    1995-09-01

    Serotonin or 5-hydroxytryptamine (5-HT) represents a family of neurotransmitters acting through the 5-HT neuroreceptors. One of these receptors, HTR3, belongs to the family of ligand gated ion channels. Activation of the HTR3 receptor mediates a variety of physiological effects in central and peripheral neurons such as cytotoxic drug-evoked emesis and nociception and is believed to influence behavior relevant to anxiety and cognitive disorders. 16 refs., 1 fig.

  6. Differential A-to-I RNA editing of the serotonin-2C receptor G-protein-coupled, HTR2C, in porcine brain tissues.

    Science.gov (United States)

    Larsen, Knud; Momeni, Jamal; Farajzadeh, Leila; Bendixen, Christian

    2016-02-01

    The HTR2C gene encodes the 5-Hydroxytryptamine (serotonin) receptor 2C, G-protein-coupled protein which functions as a serotonin receptor. The HTR2C mRNA is subject to A-to-I RNA editing mediated by adenosine deaminases acting on RNA 1 and 2 (ADAR1 and ADAR2). In the current study we examined the molecular characteristics of the porcine HTR2C gene and determined the mRNA editing of the HTR2C transcript in different tissues. The A-to-I RNA editing of HTR2C was shown to be conserved in the porcine homologue with five nucleotides edited in exon 5. A differential editing was demonstrated with a high editing frequency in the frontal cortex, parietal cortex, occipital cortex, hypothalamus, brain stem and spinal cord and significantly lower in the cerebellum. No editing was seen in the liver and kidney. The porcine HTR2C gene was found to be exclusively expressed in brain tissues. The HTR2C gene was mapped to pig chromosome X. The methylation status of the HTR2C gene was examined in brain and liver by bisulfate sequencing and a high degree of methylation was found in the two tissues, at 89 and 72%, respectively. Our data describe differences in RNA editing in various regions of the porcine brain. The differences might reflect functional differences. Similarities between pigs and humans in differential RNA editing support the use of the pig as a model organism for the study of neurological diseases. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  7. Prediction of extracellular proteases of the human pathogen Helicobacter pylori reveals proteolytic activity of the Hp1018/19 protein HtrA.

    Directory of Open Access Journals (Sweden)

    Martin Löwer

    Full Text Available Exported proteases of Helicobacter pylori (H. pylori are potentially involved in pathogen-associated disorders leading to gastric inflammation and neoplasia. By comprehensive sequence screening of the H. pylori proteome for predicted secreted proteases, we retrieved several candidate genes. We detected caseinolytic activities of several such proteases, which are released independently from the H. pylori type IV secretion system encoded by the cag pathogenicity island (cagPAI. Among these, we found the predicted serine protease HtrA (Hp1019, which was previously identified in the bacterial secretome of H. pylori. Importantly, we further found that the H. pylori genes hp1018 and hp1019 represent a single gene likely coding for an exported protein. Here, we directly verified proteolytic activity of HtrA in vitro and identified the HtrA protease in zymograms by mass spectrometry. Overexpressed and purified HtrA exhibited pronounced proteolytic activity, which is inactivated after mutation of Ser205 to alanine in the predicted active center of HtrA. These data demonstrate that H. pylori secretes HtrA as an active protease, which might represent a novel candidate target for therapeutic intervention strategies.

  8. Association of serotonin transporter (SLC6A4) and receptor (5HTR1A, 5HTR2A) polymorphisms with response to treatment with escitalopram in patients with major depressive disorder: A preliminary study.

    Science.gov (United States)

    Basu, Aniruddha; Chadda, R K; Sood, Mamta; Kaur, Harpreet; Kukreti, Ritushree

    2015-07-01

    Genetic factors have potential of predicting response to antidepressants in patients with major depressive disorder (MDD). In this study, an attempt was made to find an association between response to escitalopram in patients with MDD, and serotonin transporter (SLC6A4) and receptor (5HTR1A, 5HTR2A) polymorphisms. Fifty five patients diagnosed as suffering from MDD, were selected for the study. The patients were treated with escitalopram over a period of 6-8 wk. Severity of depression, response to treatment and side effects were assessed using standardised instruments. Genetic variations from HTR1A (rs6295), HTR2A (rs6311 and rs6313) and SLC6A4 (44 base-pair insertion/deletion at 5-HTTLPR) were genotyped. The genetic data of the responders and non-responders were compared to assess the role of genetic variants in therapeutic outcome. Thirty six (65.5%) patients responded to treatment, and 19 (34.5%) had complete remission. No association was observed for genotype and allelic frequencies of single nucleotide polymorphisms (SNPs) among remitter/non-remitter and responder/non-responder groups, and six most common side-effects, except memory loss which was significantly associated with rs6311 ( p0 =0.03). No significant association was found between the SNPs analysed and response to escitalopram in patients with MDD though a significant association was seen between the side effect of memory loss and rs6311. Studies with larger sample are required to find out genetic basis of antidepressant response in Indian patients.

  9. Association of serotonin transporter (SLC6A4 & receptor (5HTR1A, 5HTR2A polymorphisms with response to treatment with escitalopram in patients with major depressive disorder : A preliminary study

    Directory of Open Access Journals (Sweden)

    Aniruddha Basu

    2015-01-01

    Full Text Available Background & objectives: Genetic factors have potential of predicting response to antidepressants in patients with major depressive disorder (MDD. In this study, an attempt was made to find an association between response to escitalopram in patients with MDD, and serotonin transporter (SLC6A4 and receptor (5HTR1A, 5HTR2A polymorphisms. Methods: Fifty five patients diagnosed as suffering from MDD, were selected for the study. The patients were treated with escitalopram over a period of 6-8 wk. Severity of depression, response to treatment and side effects were assessed using standardised instruments. Genetic variations from HTR1A (rs6295, HTR2A (rs6311 and rs6313 and SLC6A4 (44 base-pair insertion/deletion at 5-HTTLPR were genotyped. The genetic data of the responders and non-responders were compared to assess the role of genetic variants in therapeutic outcome. Results: Thirty six (65.5% patients responded to treatment, and 19 (34.5% had complete remission. No association was observed for genotype and allelic frequencies of single nucleotide polymorphisms (SNPs among remitter/non-remitter and responder/non-responder groups, and six most common side-effects, except memory loss which was significantly associated with rs6311 ( p0 =0.03. Interpretation & conclusions: No significant association was found between the SNPs analysed and response to escitalopram in patients with MDD though a significant association was seen between the side effect of memory loss and rs6311. Studies with larger sample are required to find out genetic basis of antidepressant response in Indian patients.

  10. Design and development of a run-time monitor for multi-core architectures in cloud computing.

    Science.gov (United States)

    Kang, Mikyung; Kang, Dong-In; Crago, Stephen P; Park, Gyung-Leen; Lee, Junghoon

    2011-01-01

    Cloud computing is a new information technology trend that moves computing and data away from desktops and portable PCs into large data centers. The basic principle of cloud computing is to deliver applications as services over the Internet as well as infrastructure. A cloud is a type of parallel and distributed system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources. The large-scale distributed applications on a cloud require adaptive service-based software, which has the capability of monitoring system status changes, analyzing the monitored information, and adapting its service configuration while considering tradeoffs among multiple QoS features simultaneously. In this paper, we design and develop a Run-Time Monitor (RTM) which is a system software to monitor the application behavior at run-time, analyze the collected information, and optimize cloud computing resources for multi-core architectures. RTM monitors application software through library instrumentation as well as underlying hardware through a performance counter optimizing its computing configuration based on the analyzed data.

  11. Some uncertainty results obtained by the statistical version of the KARATE code system related to core design and safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Panka, Istvan; Hegyi, Gyoergy; Maraczy, Csaba; Temesvari, Emese [Hungarian Academy of Sciences, Budapest (Hungary). Reactor Analysis Dept.

    2017-11-15

    The best-estimate KARATE code system has been widely used for core design calculations and simulations of slow transients of VVER reactors. Recently there has been an increasing need for assessing the uncertainties of such calculations by propagating the basic input uncertainties of the models through the full calculation chain. In order to determine the uncertainties of quantities of interest during the burnup, the statistical version of the KARATE code system has been elaborated. In the first part of the paper, the main features of the new code system are discussed. The applied statistical method is based on Monte-Carlo sampling of the considered input data taking into account mainly the covariance matrices of the cross sections and/or the technological uncertainties. In the second part of the paper, only the uncertainties of cross sections are considered and an equilibrium cycle related to a VVER-440 type reactor is investigated. The burnup dependence of the uncertainties of some safety related parameters (e.g. critical boron concentration, rod worth, feedback coefficients, assembly-wise radial power and burnup distribution) are discussed and compared to the recently used limits.

  12. Design and Development of a Run-Time Monitor for Multi-Core Architectures in Cloud Computing

    Directory of Open Access Journals (Sweden)

    Junghoon Lee

    2011-03-01

    Full Text Available Cloud computing is a new information technology trend that moves computing and data away from desktops and portable PCs into large data centers. The basic principle of cloud computing is to deliver applications as services over the Internet as well as infrastructure. A cloud is a type of parallel and distributed system consisting of a collection of inter-connected and virtualized computers that are dynamically provisioned and presented as one or more unified computing resources. The large-scale distributed applications on a cloud require adaptive service-based software, which has the capability of monitoring system status changes, analyzing the monitored information, and adapting its service configuration while considering tradeoffs among multiple QoS features simultaneously. In this paper, we design and develop a Run-Time Monitor (RTM which is a system software to monitor the application behavior at run-time, analyze the collected information, and optimize cloud computing resources for multi-core architectures. RTM monitors application software through library instrumentation as well as underlying hardware through a performance counter optimizing its computing configuration based on the analyzed data.

  13. Optical designs of reflection and refraction collection optics for a JT-60SA core Thomson scattering system

    Energy Technology Data Exchange (ETDEWEB)

    Tojo, H.; Hatae, T.; Hamano, T.; Sakuma, T.; Itami, K. [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka 311-0193 (Japan)

    2013-09-15

    Collection optics for core measurements in a JT-60SA Thomson scattering system were designed. The collection optics will be installed in a limited space and have a wide field of view and wide wavelength range. Two types of the optics are therefore suggested: refraction and reflection types. The reflection system, with a large primary mirror, avoids large chromatic aberrations. Because the size limit of the primary mirror and vignetting due to the secondary mirror affect the total collection throughput, conditions that provide the high throughput are found through an optimization. A refraction system with four lenses forming an Ernostar system is also employed. The use of high-refractive-index glass materials enhances the freedom of the lens curvatures, resulting in suppression of the spherical and coma aberration. Moreover, sufficient throughput can be achieved, even with smaller lenses than that of a previous design given in [H. Tojo, T. Hatae, T. Sakuma, T. Hamano, K. Itami, Y. Aida, S. Suitoh, and D. Fujie, Rev. Sci. Instrum. 81, 10D539 (2010)]. The optical resolutions of the reflection and refraction systems are both sufficient for understanding the spatial structures in plasma. In particular, the spot sizes at the image of the optics are evaluated as ∼0.3 mm and ∼0.4 mm, respectively. The throughput for the two systems, including the pupil size and transmissivity, are also compared. The results show that good measurement accuracy (<10%) even at high electron temperatures (<30 keV) can be expected in the refraction system.

  14. [Association between dopamine (DRD2) and serotonin (5HTR2A) gene polymorphisms with the indicators of adolescent behavior adaptiveness].

    Science.gov (United States)

    Barskiĭ, V I; Aksenova, M G; Kozlova, O B; Kirillov, A V; Demin, A A; Il'inykh, L M

    2010-01-01

    The paper gives the results of a study of the impact of dopamine (DRD2) and serotonin (5HTR2A) genes on the development of personality characteristics in adolescents, by applying the Cattell (16PF) questionnaire. The study was performed in a group of 360 Moscow teenagers (185 girls and 175 boys) aged 14-17 years. The boys carrying the A1 allelle of the DRD2 gene were found to have a lower self-control, indiscipline, and impulsiveness. An association between the indicators of unconscientiousness, social introversion, and group independence was established in the girls with the G/G genotype of the 5HTR2A gene. Thus, gender differences have been revealed from the impact of dopamine and serotonin gene polymorphisms on the teenagers' personality characteristics that characterize the forms of disadaptive behavior, such as unconscientiousness, indiscipline, low self-control, and impulsiveness.

  15. Epigenetic and genetic variants in the HTR1B gene and clinical improvement in children and adolescents treated with fluoxetine.

    Science.gov (United States)

    Gassó, Patricia; Rodríguez, Natalia; Blázquez, Ana; Monteagudo, Ana; Boloc, Daniel; Plana, Maria Teresa; Lafuente, Amalia; Lázaro, Luisa; Arnaiz, Joan Albert; Mas, Sergi

    2017-04-03

    The serotonin 1B receptor (5-HT1B) is important to both the pathogenesis of major depressive disorder and the antidepressant effects of selective serotonin reuptake inhibitors. Although fluoxetine has been shown to be effective and safe in children and adolescents, not all patients experience a proper clinical response, which has led to further study into the main factors involved in this inter-individual variability. Our aim was to study the effect of epigenetic and genetic factors that could affect 5-hydroxytryptamine receptor 1B (HTR1B) gene expression, and thereby response to fluoxetine. A total of 83 children and adolescents were clinically assessed 12weeks after of initiating an antidepressant treatment with fluoxetine for the first time. We evaluated the influence of single nucleotide polymorphisms (SNPs) specifically located in transcription factor binding sites (TFBSs) on their clinical improvement. A combined genetic analysis considering the significant SNPs together with the functional variant rs130058 previously associated in our population was also performed. Moreover, we assessed, for the first time in the literature, whether methylation levels of the HTR1B promoter region could be associated with the pharmacological response. Two, rs9361233 and rs9361235, were significantly associated with clinical improvement after treatment with fluoxetine. The heterozygous genotype combination analysis showed a negative correlation with clinical improvement. The lowest improvement was experienced by patients who were heterozygous for all three SNPs. Moreover, a negative correlation was found between clinical improvement and the average methylation level of the HTR1B promoter. These results give new evidence for the role of epigenetic and genetic factors which could modulate HTR1B expression in the pharmacological response to antidepressants. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. The Autolysis of Human HtrA1 Is Governed by the Redox State of Its N-Terminal Domain

    OpenAIRE

    Ris?r, Michael W.; Poulsen, Ebbe Toftgaard; Thomsen, Line R.; Dyrlund, Thomas F.; Nielsen, Tania A.; Nielsen, Niels Chr.; Sanggaard, Kristian W.; Enghild, Jan J.

    2014-01-01

    Human HtrA1 (high-temperature requirement protein A1) belongs to a conserved family of serine proteases involved in protein quality control and cell fate. The homotrimeric ubiquitously expressed protease has chymotrypsin-like specificity and primarily targets hydrophobic stretches in selected or misfolded substrate proteins. In addition, the enzyme is capable of exerting autolytic activity by removing the N-terminal insulin-like growth factor binding protein (IGFBP)/Kazal-like tandem motif wi...

  17. Quiet Clean Short-haul Experimental Engine (QCSEE) Under-The-Wing (UTW) boiler plate nacelle and core exhaust nozzle design report

    Science.gov (United States)

    1976-01-01

    The mechanical design of the boiler plate nacelle and core exhaust nozzle for the QCSEE under the wing engine is presented. The nacelle, which features interchangeable hard-wall and acoustic panels, is to be utilized in the initial engine testing to establish acoustic requirements for the subsequent composite nacelle as well as in the QCSEE over the wing engine configuration.

  18. Genetic variant of HTR2A associates with risk of impulse control and repetitive behaviors in Parkinson's disease.

    Science.gov (United States)

    Lee, Jee-Young; Jeon, Beom S; Kim, Han-Joon; Park, Sung-Sup

    2012-01-01

    To determine the role of a serotonin 2A receptor gene (=HTR2A) variant in the development of impulse control and repetitive behaviors in Parkinson's disease. We performed a genetic association analysis to a cohort of 404 Korean patients with Parkinson's disease who had been enrolled in a previous study. Presence of impulse control and repetitive behaviors was screened using modified version of Minnesota Impulsive Disorders Interview and genotyping for HTR2A c.102T > C was performed using the TaqMan assay. The T allele, which is presumably linked to higher receptor expression, was marginally associated with impulse control and repetitive behaviors in Parkinson's disease; the genetic influence was significantly enhanced in the lower levodopa-equivalent-dose group, increasing the risk by 2.8 and 6.9 times in CT and TT carriers, respectively (p-trend = 0.011). There was no significant interaction between the c.102T > C variant and clinical risk variables such as sex, age at onset, total daily levodopa-equivalent-dose, use of dopamine agonist and daily dose of dopamine agonist. Our data support a possible contribution of genetic variation in the HTR2A to the susceptibility to impulse control and repetitive behaviors in Parkinson's disease. Copyright © 2011 Elsevier Ltd. All rights reserved.

  19. Management of grossly destroyed endodontically treated teeth with lock and key custom modified cast post and core design: A case series

    Directory of Open Access Journals (Sweden)

    E Deenadayalan

    2015-01-01

    Full Text Available The purpose of this paper is to demonstrate a more retentive custom modified lock and key design of metal cast post and core for the restoration of grossly destroyed endodontically treated molar tooth. The lock and key metal cast post consists of two parts, one in the distal canal (primary post and the other one in mesio-lingual canal (secondary post. The primary post has a lock design, while the secondary post contains the key design, both of which interlock together. Lock and key cast post, mentioned in this report can be an effective design for the management of grossly destroyed molar teeth.

  20. Management of grossly destroyed endodontically treated teeth with lock and key custom modified cast post and core design: A case series.

    Science.gov (United States)

    Deenadayalan, E; Kumar, Ashok; Tewari, Rajendra Kumar; Mishra, Surendra Kumar; Alam, Sharique

    2015-01-01

    The purpose of this paper is to demonstrate a more retentive custom modified lock and key design of metal cast post and core for the restoration of grossly destroyed endodontically treated molar tooth. The lock and key metal cast post consists of two parts, one in the distal canal (primary post) and the other one in mesio-lingual canal (secondary post). The primary post has a lock design, while the secondary post contains the key design, both of which interlock together. Lock and key cast post, mentioned in this report can be an effective design for the management of grossly destroyed molar teeth.

  1. Investigations of space-dependent safety-related parameters of a PBMR-like HTR in transient operating conditions applying a multi-group diffusion code

    Energy Technology Data Exchange (ETDEWEB)

    Druska, C. [Institute for Energy Research, Safety Research and Reactor Technology (IEF-6), Forschungszentrum Juelich (Germany); Kasselmann, St. [Institute for Energy Research, Safety Research and Reactor Technology (IEF-6), Forschungszentrum Juelich (Germany)], E-mail: s.kasselmann@fz-juelich.de; Lauer, A. [Institute for Energy Research, Safety Research and Reactor Technology (IEF-6), Forschungszentrum Juelich (Germany)

    2009-03-15

    So far, the two-dimensional reactor dynamics code TINTE (time-dependent nucleonics and temperatures) was applied for simulations of high-temperature gas cooled reactors. One limitation of TINTE is that the neutron energy spectrum is modeled by only two energy groups, namely a thermal and a fast group. Present demands for increased numerical accuracy leads to the question of how precise the two-group approximation is compared to a multi-group approach. The recently developed multi-group derivative of TINTE called MGT (multi-group TINTE) is able to handle up to 43 neutron energy groups. In this study, different scenarios (normal operation and design-basis accidents) have been simulated for a PBMR-like HTR reactor design with MGT. The effect of an increasing number of energy groups on time- and space-dependent safety-related parameters like the fuel and coolant temperature, the nuclear heat source or the xenon concentration is studied. Different ways of calculating the material cross-sections are compared as well.

  2. The effects of a HTR2B stop codon and testosterone on energy metabolism and beta cell function among antisocial Finnish males.

    Science.gov (United States)

    Tikkanen, Roope; Saukkonen, Tero; Fex, Malin; Bennet, Hedvig; Rautiainen, Marja-Riitta; Paunio, Tiina; Koskinen, Mika; Panarsky, Rony; Bevilacqua, Laura; Sjöberg, Rickard L; Tiihonen, Jari; Virkkunen, Matti

    2016-10-01

    Herein, we examined insulin resistance (IR), insulin sensitivity (IS), beta cell activity, and glucose metabolism in subjects with antisocial personality disorder (ASPD), and whether the serotonin 2B (5-HT2B) receptor and testosterone have a role in energy metabolism. A cohort of subjects belonging to a founder population that included 98 ASPD males, aged 25-30, was divided into groups based on the presence of a heterozygous 5-HT2B receptor loss-of-function gene mutation (HTR2B Q20*; n = 9) or not (n = 89). Serum glucose and insulin levels were measured in a 5 h oral glucose tolerance test (75 g) and indices describing IR, IS, and beta cell activity were calculated. Body mass index (BMI) was also determined. Concentrations of the serotonin metabolite 5-hydroxyindoleacetic acid were measured in cerebrospinal fluid, and testosterone levels from serum. An IR-like state comprising high IR, low IS, and high beta cell activity indices was observed among ASPD subjects without the HTR2B Q20* allele. By contrast, being an ASPD HTR2B Q20* carrier appeared to be preventive of these pathophysiologies. The HTR2B Q20* allele and testosterone predicted lower BMI independently, but an interaction between HTR2B Q20* and testosterone lead to increased insulin sensitivity among HTR2B Q20* carriers with low testosterone levels. The HTR2B Q20* allele also predicted reduced beta cell activity and enhanced glucose metabolism. Reduced 5-HT2B receptor function at low or normal testosterone levels may be protective of obesity. Results were observed among Finnish males having an antisocial personality disorder, which limits the generality. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Correlation Between Expression of High Temperature Requirement Serine Protease A1 (HtrA1) in Nucleus Pulposus and T2 Value of Magnetic Resonance Imaging.

    Science.gov (United States)

    Li, Dapeng; Yue, Jiawei; Jiang, Lu; Huang, Yonghui; Sun, Jifu; Wu, Yan

    2017-04-22

    BACKGROUND Degrading enzymes play an important role in the process of disc degeneration. The objective of this study was to investigate the correlation between the expression of high temperature requirement serine protease A1 (HtrA1) in the nucleus pulposus and the T2 value of the nucleus pulposus region in magnetic resonance imaging (MRI). MATERIAL AND METHODS Thirty-six patients who had undergone surgical excision of the nucleus pulposus were examined by MRI before surgery. Pfirrmann grading of the target intervertebral disc was performed according to the sagittal T2-weighted imaging, and the T2 value of the target nucleus pulposus was measured according to the median sagittal T2 mapping. The correlation between the Pfirrmann grade and the T2 value was analyzed. The expression of HtrA1 in the nucleus pulposus was analyzed by RT-PCR and Western blot. The correlation between the expression of HtrA1 and the T2 value was analyzed. RESULTS The T2 value of the nucleus pulposus region was 33.11-167.91 ms, with an average of 86.64±38.73 ms. According to Spearman correlation analysis, there was a rank correlation between T2 value and Pfirrmann grade (Pcorrelation coefficient (rs)=-0.93617. There was a linear correlation between the mRNA level of HtrA1 and T2 value in nucleus pulposus tissues (a=3.88, b=-0.019, F=112.63, Pcorrelation between the expression level of HtrA1 protein and the T2 value in the nucleus pulposus tissues (a=3.30, b=-0.016, F=93.15, P<0.0001) and normalized regression coefficient=-0.86. CONCLUSIONS The expression of HtrA1 was strongly related to the T2 value, suggesting that HtrA1 plays an important role in the pathological process of intervertebral disc degeneration.

  4. The role of serine protease HtrA in acute ulcerative enterocolitis and extra-intestinal immune responses during Campylobacter jejuni infection of gnotobiotic IL-10 deficient mice

    Directory of Open Access Journals (Sweden)

    Markus M. Heimesaat

    2014-06-01

    Full Text Available Campylobacter jejuni infections have a high prevalence worldwide and represent a significant socioeconomic burden. C. jejuni can cross the intestinal epithelial barrier as visualised in biopsies derived from human patients and animal models, however, the underlying molecular mechanisms and associated immunopathology are still not well understood. We have recently shown that the secreted serine protease HtrA plays a key role in C. jejuni cellular invasion and transmigration across polarised epithelial cells in vitro. In the present in vivo study we investigated the role of HtrA during C. jejuni infection of mice. We used the gnotobiotic IL-10-/- mouse model to study campylobacteriosis following peroral infection with the C. jejuni wild-type strain NCTC11168 and the isogenic, non-polar NCTC11168ΔhtrA deletion mutant. Six days post infection (p.i. with either strain mice harboured comparable intestinal C. jejuni loads, whereas ulcerative enterocolitis was less pronounced in mice infected with the ΔhtrA mutant strain. Moreover, ΔhtrA mutant infected mice displayed lower apoptotic cell numbers in the large intestinal mucosa, less colonic accumulation of neutrophils, macrophages and monocytes, lower large intestinal nitric oxide, IFN-γ and IL-6 as well as lower TNF-α and IL-6 serum concentrations as compared to wild-type strain infected mice at day 6 p.i. Notably, immunopathological responses were not restricted to the intestinal tract given that liver and kidneys exhibited mild histopathological changes six days p.i. with either C. jejuni strain. We also found that hepatic and renal nitric oxide levels or renal TNF-α concentrations were lower in the ΔhtrA mutant as compared to wild-type strain infected mice. In conclusion, we show here that the C. jejuni HtrA protein plays a pivotal role in inducing host cell apoptosis and immunopathology during murine campylobacteriosis in the gut in vivo.

  5. The role of serine protease HtrA in acute ulcerative enterocolitis and extra-intestinal immune responses during Campylobacter jejuni infection of gnotobiotic IL-10 deficient mice.

    Science.gov (United States)

    Heimesaat, Markus M; Alutis, Marie; Grundmann, Ursula; Fischer, André; Tegtmeyer, Nicole; Böhm, Manja; Kühl, Anja A; Göbel, Ulf B; Backert, Steffen; Bereswill, Stefan

    2014-01-01

    Campylobacter jejuni infections have a high prevalence worldwide and represent a significant socioeconomic burden. C. jejuni can cross the intestinal epithelial barrier as visualized in biopsies derived from human patients and animal models, however, the underlying molecular mechanisms and associated immunopathology are still not well understood. We have recently shown that the secreted serine protease HtrA (high temperature requirement A) plays a key role in C. jejuni cellular invasion and transmigration across polarized epithelial cells in vitro. In the present in vivo study we investigated the role of HtrA during C. jejuni infection of mice. We used the gnotobiotic IL-10(-/-) mouse model to study campylobacteriosis following peroral infection with the C. jejuni wild-type (WT) strain NCTC11168 and the isogenic, non-polar NCTC11168ΔhtrA deletion mutant. Six days post infection (p.i.) with either strain mice harbored comparable intestinal C. jejuni loads, whereas ulcerative enterocolitis was less pronounced in mice infected with the ΔhtrA mutant strain. Moreover, ΔhtrA mutant infected mice displayed lower apoptotic cell numbers in the large intestinal mucosa, less colonic accumulation of neutrophils, macrophages and monocytes, lower large intestinal nitric oxide, IFN-γ, and IL-6 as well as lower TNF-α and IL-6 serum concentrations as compared to WT strain infected mice at day 6 p.i. Notably, immunopathological responses were not restricted to the intestinal tract given that liver and kidneys exhibited mild histopathological changes 6 days p.i. with either C. jejuni strain. We also found that hepatic and renal nitric oxide levels or renal TNF-α concentrations were lower in the ΔhtrA mutant as compared to WT strain infected mice. In conclusion, we show here that the C. jejuni HtrA protein plays a pivotal role in inducing host cell apoptosis and immunopathology during murine campylobacteriosis in the gut in vivo.

  6. Up-regulation of lymphocyte antigen 6 complex expression in side-population cells derived from a human trophoblast cell line HTR-8/SVneo.

    Science.gov (United States)

    Inagaki, Tetsunori; Kusunoki, Soshi; Tabu, Kouichi; Okabe, Hitomi; Yamada, Izumi; Taga, Tetsuya; Matsumoto, Akemi; Makino, Shintaro; Takeda, Satoru; Kato, Kiyoko

    2016-01-01

    The continual proliferation and differentiation of trophoblasts are critical for the maintenance of pregnancy. It is well known that the tissue stem cells are associated with the development of tissues and pathologies. It has been demonstrated that side-population (SP) cells identified by fluorescence-activated cell sorting (FACS) are enriched with stem cells. The SP cells in HTR-8/SVneo cells derived from human primary trophoblast cells were isolated by FACS. HTR-8/SVneo-SP cell cultures generated both SP and non-SP (NSP) subpopulations. In contrast, NSP cell cultures produced NSP cells and failed to produce SP cells. These SP cells showed self-renewal capability by serial colony-forming assay. Microarray expression analysis using a set of HTR-8/SVneo-SP and -NSP cells revealed that SP cells overexpressed several stemness genes including caudal type homeobox2 (CDX2) and bone morphogenic proteins (BMPs), and lymphocyte antigen 6 complex locus D (LY6D) gene was the most highly up-regulated in HTR-8/SVneo-SP cells. LY6D gene reduced its expression in the course of a 7-day cultivation in differentiation medium. SP cells tended to reduce its fraction by treatment of LY6D siRNA indicating that LY6D had potential to maintain cell proliferation of HTR-8/SVneo-SP cells. On ontology analysis, epithelial-mesenchymal transition (EMT) pathway was involved in the up-regulated genes on microarray analysis. HTR-SVneo-SP cells showed enhanced migration. This is the first report that LY6D was important for the maintenance of HTR-8/SVneo-SP cells. EMT was associated with the phenotype of these SP cells.

  7. A finite element study of teeth restored with post and core: Effect of design, material, and ferrule

    Directory of Open Access Journals (Sweden)

    Viram Upadhyaya

    2016-01-01

    Conclusion: A rigid material with high modulus of elasticity for post and core system creates most uniform stress distribution pattern. Ferrule provides uniform distribution of stresses and decreases the cervical stresses.

  8. Building core capacities at the designated points of entry according to the International Health Regulations 2005: a review of the progress and prospects in Taiwan

    Directory of Open Access Journals (Sweden)

    Hsiao-Hsuan Chiu

    2014-07-01

    Full Text Available Background: As designated points of entry (PoEs play a critical role in preventing the transmission of international public health risks, huge efforts have been invested in Taiwan to improve the core capacities specified in the International Health Regulations 2005 (IHR 2005. This article reviews how Taiwan strengthened the core capacities at the Taoyuan International Airport (TIA and the Port of Kaohsiung (PoK by applying a new, practicable model. Design: An IHR PoE program was initiated for implementing the IHR core capacities at designated PoEs. The main methods of this program were 1 identifying the designated PoEs according to the pre-determined criteria, 2 identifying the competent authority for each health measure, 3 building a close collaborative relationship between stakeholders from the central and PoE level, 4 designing three stages of systematic assessment using the assessment tool published by the World Health Organization (WHO, and 5 undertaking action plans targeting the gaps identified by the assessments. Results: Results of the self-assessment, preliminary external assessment, and follow-up external assessment revealed a continuous progressive trend at the TIA (86, 91, and 100%, respectively, and at the PoK (77, 97, and 99.9%, respectively. The results of the follow-up external assessment indicated that both these designated PoEs already conformed to the IHR requirements. These achievements were highly associated with strong collaboration, continuous empowerment, efficient resource integration, and sustained commitments. Conclusions: Considering that many countries had requested for an extension on the deadline to fulfill the IHR 2005 core capacity requirements, Taiwan's experiences can be a source of learning for countries striving to fully implement these requirements. Further, in order to broaden the scope of public health protection into promoting global security, Taiwan will keep its commitments on multisectoral cooperation

  9. Study of the PWR REA pulse width for realistic UO2 and MOX core designs using 3D kinetics methods

    Energy Technology Data Exchange (ETDEWEB)

    Ferroukhi, Hakim [Laboratory for Reactor Physics and Systems Behaviour, Paul Scherrer Institut, CH 5232 Villigen PSI (Switzerland)], E-mail: Hakim.Ferroukhi@psi.ch; Zimmermann, Martin A. [Laboratory for Reactor Physics and Systems Behaviour, Paul Scherrer Institut, CH 5232 Villigen PSI (Switzerland)

    2009-08-15

    For the development of new acceptance criteria for the analysis of Rod-Ejection-Accidents (REA) in Pressurized Water Reactor UO2 cores, full-width-at-half-maximum power pulse widths in the range 25-40 ms were employed in the analytical transient fuel behaviour studies. Due to the operation of MOX cores in Switzerland, a study using the CORETRAN 3D kinetics code was carried out at PSI to investigate and compare on the basis of real operated cycles MOX and UO2 cores, the pulse width magnitude as function of rod reactivity for postulated super-prompt critical REAs. This study is presented in a first part of this paper. Thereafter, to quantify the variation in pulse width when applying a different 3D kinetic solver, a benchmarking with the SIMULATE-3K code is carried out. This code-to-code comparison aims also to serve as an assessment of SIMULATE-3K for REA analyses of the Swiss cores since only CORETRAN had so far been benchmarked at PSI for this type of applications. Finally, to provide confidence in the results, particularly for pulse widths below 25 ms, sensitivity studies are performed to assess the effects of specific modelling options and assumptions applied in the REA 3D kinetic analysis and to compare the sensitivities between UO2 and MOX cores. On the basis of all these studies, it is found that the MOX core pulse width is usually around 5 to 10 ms lower than for UO2 cores. For rod worths close to 2.0$, corresponding to around 500 pcm above prompt criticality and which was obtained for many of the investigated MOX cycles particularly at end-of-cycle conditions, a representative MOX pulse width magnitude is found to be around 15 ms. To shortly address the applicability of these results, i.e. obtained for very specific MOX cores, additional calculations were performed for hypothetical cases with increased MOX core fractions and with higher MOX assembly Pu enrichments. And it was found that even for these types of cores, the pulse width would, although being

  10. Modelling of HTR Confinement Behaviour during Accidents Involving Breach of the Helium Pressure Boundary

    Directory of Open Access Journals (Sweden)

    Joan Fontanet

    2009-01-01

    Full Text Available Development of HTRs requires the performance of a thorough safety study, which includes accident analyses. Confinement building performance is a key element of the system since the behaviour of aerosol and attached fission products within the building is of an utmost relevance in terms of the potential source term to the environment. This paper explores the available simulation capabilities (ASTEC and CONTAIN codes and illustrates the performance of a postulated HTR vented confinement under prototypical accident conditions by a scoping study based on two accident sequences characterized by Helium Pressure Boundary breaches, a small and a large break. The results obtained indicate that both codes predict very similar thermal-hydraulic responses of the confinement both in magnitude and timing. As for the aerosol behaviour, both codes predict that most of the inventory coming into the confinement is eventually depleted on the walls and only about 1% of the aerosol dust is released to the environment. The crosscomparison of codes states that largest differences are in the intercompartmental flows and the in-compartment gas composition.

  11. Nuclear graphite wear properties and estimation of graphite dust production in HTR-10

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Xiaowei, E-mail: xwluo@tsinghua.edu.cn; Wang, Xiaoxin; Shi, Li; Yu, Xiaoyu; Yu, Suyuan

    2017-04-15

    Highlights: • Graphite dust. • The wear properties of graphite. • Pebble bed. • High Temperature Gas-cooled Reactor. • Fuel element. - Abstract: The issue of the graphite dust has been a research focus for the safety of High Temperature Gas-cooled Reactors (HTGRs), especially for the pebble bed reactors. Most of the graphite dust is produced from the wear of fuel elements during cycling of fuel elements. However, due to the complexity of the motion of the fuel elements in the pebble bed, there is no systematic method developed to predict the amount the graphite dust in a pebble bed reactor. In this paper, the study of the flow of the fuel elements in the pebble bed was carried out. Both theoretical calculation and numerical analysis by Discrete Element Method (DEM) software PFC3D were conducted to obtain the normal forces and sliding distances of the fuel elements in pebble bed. The wearing theory was then integrated with PFC3D to estimate the amount of the graphite dust in a pebble bed reactor, 10 MW High Temperature gas-cooled test Reactor (HTR-10).

  12. The impact of serine protease HtrA in apoptosis, intestinal immune responses and extra-intestinal histopathology during Campylobacter jejuni infection of infant mice.

    Science.gov (United States)

    Heimesaat, Markus M; Fischer, André; Alutis, Marie; Grundmann, Ursula; Boehm, Manja; Tegtmeyer, Nicole; Göbel, Ulf B; Kühl, Anja A; Bereswill, Stefan; Backert, Steffen

    2014-01-01

    Campylobacter jejuni has emerged as a leading cause of bacterial enterocolitis. The serine protease HtrA has been shown to be a pivotal, novel C. jejuni virulence factor involved in cell invasion and transmigration across polarised epithelial cells in vitro. However, the functional relevance of the htrA gene for the interaction of C. jejuni with the host immune system in the infant mouse infection model has not been investigated so far. Here we studied the role of C. jejuni htrA during infection of 3-weeks-old infant mice. Immediately after weaning, conventional wild-type mice were perorally infected with the NCTC11168∆htrA mutant (∆htrA) or the parental wild-type strain. Approximately one third of infected infant mice suffered from bloody diarrhea until day 7 post infection (p.i.), whereas colonic histopathological changes were rather moderate but comparable between the two strains. Interestingly, parental, but not ∆htrA mutant infected mice, displayed a multifold increase of apoptotic cells in the colonic mucosa at day 7 p.i., which was paralleled by higher colonic levels of pro-inflammatory cytokines such as TNF-α and IFN-γ and the matrix-degrading enzyme matrixmetalloproteinase-2 (MMP-2). Furthermore, higher numbers of proliferating cells could be observed in the colon of ∆htrA infected mice as compared to the parental wild-type strain. Remarkably, as early as 7 days p.i. infant mice also exhibited inflammatory changes in extra-intestinal compartments such as liver, kidneys and lungs, which were less distinct in kidneys and lungs following ∆htrA versus parental strain infection. However, live C. jejuni bacteria could not be found in these organs, suggesting the induction of systemic effects during intestinal infection. Upon C. jejuni ∆htrA strain infection of infant mice, intestinal and extra-intestinal pro-inflammatory immune responses were ameliorated in the infant mouse model system. Future studies will shed further light onto the molecular

  13. Building core capacities at the designated points of entry according to the International Health Regulations 2005: a review of the progress and prospects in Taiwan.

    Science.gov (United States)

    Chiu, Hsiao-Hsuan; Hsieh, Jui-Wei; Wu, Yi-Chun; Chou, Jih-Haw; Chang, Feng-Yee

    2014-01-01

    As designated points of entry (PoEs) play a critical role in preventing the transmission of international public health risks, huge efforts have been invested in Taiwan to improve the core capacities specified in the International Health Regulations 2005 (IHR 2005). This article reviews how Taiwan strengthened the core capacities at the Taoyuan International Airport (TIA) and the Port of Kaohsiung (PoK) by applying a new, practicable model. An IHR PoE program was initiated for implementing the IHR core capacities at designated PoEs. The main methods of this program were 1) identifying the designated PoEs according to the pre-determined criteria, 2) identifying the competent authority for each health measure, 3) building a close collaborative relationship between stakeholders from the central and PoE level, 4) designing three stages of systematic assessment using the assessment tool published by the World Health Organization (WHO), and 5) undertaking action plans targeting the gaps identified by the assessments. Results of the self-assessment, preliminary external assessment, and follow-up external assessment revealed a continuous progressive trend at the TIA (86, 91, and 100%, respectively), and at the PoK (77, 97, and 99.9%, respectively). The results of the follow-up external assessment indicated that both these designated PoEs already conformed to the IHR requirements. These achievements were highly associated with strong collaboration, continuous empowerment, efficient resource integration, and sustained commitments. Considering that many countries had requested for an extension on the deadline to fulfill the IHR 2005 core capacity requirements, Taiwan's experiences can be a source of learning for countries striving to fully implement these requirements. Further, in order to broaden the scope of public health protection into promoting global security, Taiwan will keep its commitments on multisectoral cooperation, human resource capacity building, and

  14. Rational design of high-surface-area carbon nanotube/microporous carbon core-shell nanocomposites for supercapacitor electrodes.

    Science.gov (United States)

    Yao, Yuanyuan; Ma, Cheng; Wang, Jitong; Qiao, Wenming; Ling, Licheng; Long, Donghui

    2015-03-04

    All-carbon-based carbon nanotube (CNT)/microporous carbon core-shell nanocomposites, in which a CNT as the core and high-surface-area microporous carbon as the shell, have been prepared by in situ resorcinol-formaldehyde resin coating of CNTs, followed by carbonization and controlled KOH activation. The obtained nanocomposites have very high Brunauer-Emmett-Teller surface areas (up to 1700 m(2)/g), narrow pore size distribution (microporous carbon shell can be easily tuned from 20 to 215 nm by changing the carbon precursor/CNT mass ratio. In such a unique core-shell structure, the CNT core could mitigate the key issue related to the low electronic conductivity of microporous carbons. On the other hand, the 1D tubular structure with a short pore-pathway micropore as well as a 3D entangled network could increase the utilization degree of the overall porosity and improve the electrode kinetics. Thus, these CNT/microporous carbon core-shell nanocomposites exhibit a great potential as an electrode material for supercapacitors, which could deliver high specific capacitance of 237 F/g, excellent rate performance with 75% maintenance from 0.1 to 50 A/g, and high cyclability in H2SO4 electrolyte. Moreover, the precisely controlled microporous carbon shells may allow them to serve as excellent model systems for microporous carbons, in general, to illustrate the role of the pore length on the diffusion and kinetics inside the micropores.

  15. HTR8/SVneo Cells Display Trophoblast Progenitor Cell-Like Characteristics Indicative of Self-Renewal, Repopulation Activity, and Expression of “Stemness-” Associated Transcription Factors

    Directory of Open Access Journals (Sweden)

    Maja Weber

    2013-01-01

    Full Text Available Introduction. JEG3 is a choriocarcinoma—and HTR8/SVneo a transformed extravillous trophoblast—cell line often used to model the physiologically invasive extravillous trophoblast. Past studies suggest that these cell lines possess some stem or progenitor cell characteristics. Aim was to study whether these cells fulfill minimum criteria used to identify stem-like (progenitor cells. In summary, we found that the expression profile of HTR8/SVneo (CDX2+, NOTCH1+, SOX2+, NANOG+, and OCT- is distinct from JEG3 (CDX2+ and NOTCH1+ as seen only in human-serum blocked immunocytochemistry. This correlates with HTR8/SVneo’s self-renewal capacities, as made visible via spheroid formation and multi-passagability in hanging drops protocols paralleling those used to maintain embryoid bodies. JEG3 displayed only low propensity to form and reform spheroids. HTR8/SVneo spheroids migrated to cover and seemingly repopulate human chorionic villi during confrontation cultures with placental explants in hanging drops. We conclude that HTR8/SVneo spheroid cells possess progenitor cell traits that are probably attained through corruption of “stemness-” associated transcription factor networks. Furthermore, trophoblastic cells are highly prone to unspecific binding, which is resistant to conventional blocking methods, but which can be alleviated through blockage with human serum.

  16. Design and Synthesis of Core-Shell-Shell Upconversion Nanoparticles for NIR-Induced Drug Release, Photodynamic Therapy, and Cell Imaging.

    Science.gov (United States)

    Wang, Hao; Han, Ren-lu; Yang, Li-ming; Shi, Jun-hui; Liu, Zong-jun; Hu, Yu; Wang, You; Liu, Shu-juan; Gan, Yang

    2016-02-01

    Novel core-shell-shell structured nanoparticles 75 nm in diameter with all-in-one "smart" functional capabilities for simultaneous photoresponsive drug release, photodynamic therapy, and cell imaging are designed and prepared. These nanoparticles consist of an upconversion (UC) emission core, a photosensitizer-embodied silica sandwich shell, and a β-cyclodextrin (β-CD) gated mesoporous silica outmost shell with drugs (Rhodamine B as a model) loaded inside. We show in this proof-of-concept demonstration that, under 980 nm near-infrared irradiation, UC 540 nm green light emissions were emitted for cell imaging, and 660 nm red light emissions were excited for activating photosensitizers to generate singlet oxygen, which could be exploited directly to kill cancer cells and simultaneously dissociate β-CD gatekeeper to release drugs. The preliminary results reported here will shed new light on the future design and applications of multifunctional platforms for cancer therapy and diagnostic.

  17. Sequentially releasing dual-drug-loaded PLGA-casein core/shell nanomedicine: design, synthesis, biocompatibility and pharmacokinetics.

    Science.gov (United States)

    Narayanan, Sreeja; Pavithran, Maya; Viswanath, Aiswarya; Narayanan, Dhanya; Mohan, Chandini C; Manzoor, K; Menon, Deepthy

    2014-05-01

    The present study reports an engineered poly-l-lactide-co-glycolic acid (PLGA)-casein polymer-protein hybrid nanocarrier 190±12nm in size entrapping a combination of chemically distinct (hydrophobic/hydrophilic) model drugs. A simple emulsion-precipitation route was adopted to prepare nearly monodispersed nanoparticles with distinct core/shell morphology entrapping paclitaxel (Ptx) in the core and epigallocatechin gallate (EGCG) in the shell, with the intention of providing a sequential and sustained release of these drugs. The idea was that an early release of EGCG would substantially increase the sensitivity of Ptx to cancer, thereby providing improved therapeutics at lower concentrations, with less toxicity. The hemo- and immunocompatibility of the core/shell nanomedicine was established in this study. The core/shell nanoparticles injected via the tail vein in Sprague-Dawley rats did not reveal any organ toxicity as was evident from histopathological evaluations of the major organs. In vivo pharmacokinetic studies in rats by high-performance liquid chromatography confirmed a sustained and sequential release of both the drugs in plasma, indicating prolonged circulation of the nanomedicine and enhanced availability of the drugs when compared to the bare drugs. Overall, the polymer-protein multilayered nanoparticles proved to be a promising platform for nanopolypharmaceutics. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  18. On the Design of Energy Efficient Optical Networks with Software Defined Networking Control Across Core and Access Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Yan, Ying; Dittmann, Lars

    2013-01-01

    This paper presents a Software Defined Networking (SDN) control plane based on an overlay GMPLS control model. The SDN control platform manages optical core networks (WDM/DWDM networks) and the associated access networks (GPON networks), which makes it possible to gather global information...

  19. HardwareSoftware Co-design for Heterogeneous Multi-core Platforms The hArtes Toolchain

    CERN Document Server

    2012-01-01

    This book describes the results and outcome of the FP6 project, known as hArtes, which focuses on the development of an integrated tool chain targeting a heterogeneous multi core platform comprising of a general purpose processor (ARM or powerPC), a DSP (the diopsis) and an FPGA. The tool chain takes existing source code and proposes transformations and mappings such that legacy code can easily be ported to a modern, multi-core platform. Benefits of the hArtes approach, described in this book, include: Uses a familiar programming paradigm: hArtes proposes a familiar programming paradigm which is compatible with the widely used programming practice, irrespective of the target platform. Enables users to view multiple cores as a single processor: the hArtes approach abstracts away the heterogeneity as well as the multi-core aspect of the underlying hardware so the developer can view the platform as consisting of a single, general purpose processor. Facilitates easy porting of existing applications: hArtes provid...

  20. Technology Assessment HTR. Part 7. Social support for the introduction of the High Temperature Reactor; Technology assessment HTR. Deel 7. Maatschappelijk draagvlak voor de introductie van de Hoge Temperatuur Reactor

    Energy Technology Data Exchange (ETDEWEB)

    De Ruiter, W. [Vakgroep Natuurwetenschap en Samenleving NWS, Rijksuniversiteit Utrecht, Utrecht (Netherlands)

    1996-06-01

    The safety of nuclear power plants is the main subject in risk analysis and risk perception of nuclear energy. The question is if a substantial increase in safety according to the classic risk analysis will lead to a decrease in the percepted risks of nuclear energy. In this report the uncertainties in existing risk analysis are dealt with. The results of public risk perception studies of nuclear power are then analysed and possible changes in the public risk perception in the case of the introduction of the HTR is dealt with. Results and conclusions are presented. 4 tabs., 71 refs.

  1. Nuclear safety analyses and core design calculations to convert the Texas A & M University Nuclear Science Center reactor to low enrichment uranium fuel. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Parish, T.A.

    1995-03-02

    This project involved performing the nuclear design and safety analyses needed to modify the license issued by the Nuclear Regulatory Commission to allow operation of the Texas A& M University Nuclear Science Center Reactor (NSCR) with a core containing low enrichment uranium (LEU) fuel. The specific type of LEU fuel to be considered was the TRIGA 20-20 fuel produced by General Atomic. Computer codes for the neutronic analyses were provided by Argonne National Laboratory (ANL) and the assistance of William Woodruff of ANL in helping the NSCR staff to learn the proper use of the codes is gratefully acknowledged. The codes applied in the LEU analyses were WIMSd4/m, DIF3D, NCTRIGA and PARET. These codes allowed full three dimensional, temperature and burnup dependent calculations modelling the NSCR core to be performed for the first time. In addition, temperature coefficients of reactivity and pulsing calculations were carried out in-house, whereas in the past this modelling had been performed at General Atomic. In order to benchmark the newly acquired codes, modelling of the current NSCR core with highly enriched uranium fuel was also carried out. Calculated results were compared to both earlier licensing calculations and experimental data and the new methods were found to achieve excellent agreement with both. Therefore, even if an LEU core is never loaded at the NSCR, this project has resulted in a significant improvement in the nuclear safety analysis capabilities established and maintained at the NSCR.

  2. Rapid paracellular transmigration of Campylobacter jejuni across polarized epithelial cells without affecting TER: role of proteolytic-active HtrA cleaving E-cadherin but not fibronectin

    LENUS (Irish Health Repository)

    Boehm, Manja

    2012-04-25

    AbstractBackgroundCampylobacter jejuni is one of the most important bacterial pathogens causing food-borne illness worldwide. Crossing the intestinal epithelial barrier and host cell entry by C. jejuni is considered the primary reason of damage to the intestinal tissue, but the molecular mechanisms as well as major bacterial and host cell factors involved in this process are still widely unclear.ResultsIn the present study, we characterized the serine protease HtrA (high-temperature requirement A) of C. jejuni as a secreted virulence factor with important proteolytic functions. Infection studies and in vitro cleavage assays showed that C. jejuni’s HtrA triggers shedding of the extracellular E-cadherin NTF domain (90 kDa) of non-polarised INT-407 and polarized MKN-28 epithelial cells, but fibronectin was not cleaved as seen for H. pylori’s HtrA. Deletion of the htrA gene in C. jejuni or expression of a protease-deficient S197A point mutant did not lead to loss of flagella or reduced bacterial motility, but led to severe defects in E-cadherin cleavage and transmigration of the bacteria across polarized MKN-28 cell layers. Unlike other highly invasive pathogens, transmigration across polarized cells by wild-type C. jejuni is highly efficient and is achieved within a few minutes of infection. Interestingly, E-cadherin cleavage by C. jejuni occurs in a limited fashion and transmigration required the intact flagella as well as HtrA protease activity, but does not reduce transepithelial electrical resistance (TER) as seen with Salmonella, Shigella, Listeria or Neisseria.ConclusionThese results suggest that HtrA-mediated E-cadherin cleavage is involved in rapid crossing of the epithelial barrier by C. jejuni via a very specific mechanism using the paracellular route to reach basolateral surfaces, but does not cleave the fibronectin receptor which is necessary for cell entry.

  3. HTR3B is associated with alcoholism with antisocial behavior and alpha EEG power—an intermediate phenotype for alcoholism and co-morbid behaviors

    Science.gov (United States)

    Ducci, Francesca; Enoch, Mary-Anne; Yuan, Qiaoping; Shen, Pei-Hong; White, Kenneth V.; Hodgkinson, Colin; Albaugh, Bernard; Virkkunen, Matti; Goldman, David

    2009-01-01

    Alcohol use disorders (AUD) with co-morbid antisocial personality disorder (ASPD) have been associated with serotonin (5-HT) dysfunction. 5-HT3 receptors are potentiated by ethanol and appear to modulate reward. 5-HT3 receptor antagonists may be useful in the treatment of early-onset alcoholics with co-morbid ASPD. Low-voltage alpha electroencephalogram (EEG) power, a highly heritable trait, has been associated with both AUD and ASPD. A recent whole genome linkage scan in one of our samples, Plains American Indians (PI), has shown a suggestive linkage peak for alpha power at the 5-HT3R locus. We tested whether genetic variation within the HTR3A and HTR3B genes influences vulnerability to AUD with comorbid ASPD (AUD + ASPD) and moderates alpha power. Our study included three samples: 284 criminal alcoholic Finnish Caucasians and 234 controls; two independent community-ascertained samples with resting EEG recordings: a predominantly Caucasian sample of 191 individuals (Bethesda) and 306 PI. In the Finns, an intronic HTR3B SNP rs3782025 was associated with AUD + ASPD (P = .004). In the Bethesda sample, the same allele predicted lower alpha power (P = 7.37e-5). Associations between alpha power and two other HTR3B SNPs were also observed among PI (P = .03). One haplotype in the haplotype block at the 3′ region of the gene that included rs3782025 was associated with AUD + ASPD in the Finns (P = .02) and with reduced alpha power in the Bethesda population (P = .00009). Another haplotype in this block was associated with alpha power among PI (P = .03). No associations were found for HTR3A. Genetic variation within HTR3B may influence vulnerability to develop AUD with comorbid ASPD. 5-HT3R might contribute to the imbalance between excitation and inhibition that characterize the brain of alcoholics. PMID:19185213

  4. HTR3B is associated with alcoholism with antisocial behavior and alpha EEG power--an intermediate phenotype for alcoholism and co-morbid behaviors.

    Science.gov (United States)

    Ducci, Francesca; Enoch, Mary-Anne; Yuan, Qiaoping; Shen, Pei-Hong; White, Kenneth V; Hodgkinson, Colin; Albaugh, Bernard; Virkkunen, Matti; Goldman, David

    2009-02-01

    Alcohol use disorders (AUD) with co-morbid antisocial personality disorder (ASPD) have been associated with serotonin (5-HT) dysfunction. 5-HT3 receptors are potentiated by ethanol and appear to modulate reward. 5-HT3 receptor antagonists may be useful in the treatment of early-onset alcoholics with co-morbid ASPD. Low-voltage alpha electroencephalogram (EEG) power, a highly heritable trait, has been associated with both AUD and ASPD. A recent whole genome linkage scan in one of our samples, Plains American Indians (PI), has shown a suggestive linkage peak for alpha power at the 5-HT3R locus. We tested whether genetic variation within the HTR3A and HTR3B genes influences vulnerability to AUD with comorbid ASPD (AUD+ASPD) and moderates alpha power. Our study included three samples: 284 criminal alcoholic Finnish Caucasians and 234 controls; two independent community-ascertained samples with resting EEG recordings: a predominantly Caucasian sample of 191 individuals (Bethesda) and 306 PI. In the Finns, an intronic HTR3B SNP rs3782025 was associated with AUD+ASPD (P=.004). In the Bethesda sample, the same allele predicted lower alpha power (P=7.37e(-5)). Associations between alpha power and two other HTR3B SNPs were also observed among PI (P=.03). One haplotype in the haplotype block at the 3' region of the gene that included rs3782025 was associated with AUD+ASPD in the Finns (P=.02) and with reduced alpha power in the Bethesda population (P=.00009). Another haplotype in this block was associated with alpha power among PI (P=.03). No associations were found for HTR3A. Genetic variation within HTR3B may influence vulnerability to develop AUD with comorbid ASPD. 5-HT3R might contribute to the imbalance between excitation and inhibition that characterize the brain of alcoholics.

  5. Design and numerical analysis of a THz square porous-core photonic crystal fiber for low flattened dispersion, ultrahigh birefringence.

    Science.gov (United States)

    Luo, Jianfeng; Tian, Fengjun; Qu, Hongkun; Li, Li; Zhang, Jianzhong; Yang, Xinhua; Yuan, Libo

    2017-08-20

    We propose a kind of square porous-core photonic crystal fiber (PCF) for polarization-maintaining terahertz (THz) wave guidance. An asymmetry is introduced by implementing rectangular array air holes in the porous core of the PCF, and ultrahigh birefringence and low effective material loss (EML) can be achieved simultaneously. The properties of THz wave propagation are analyzed numerically in detail. The numerical results indicate that the proposed fiber offers a high birefringence of 0.063 and a low EML of 0.081  cm(-1) at 1 THz. Moreover, a very low flattened dispersion profile is observed over a wide frequency domain of 0.85-1.9 THz. The zero flattened dispersion can be controlled. It is predicted that this PCF would be used potentially in polarization maintaining and dispersion management of THz waves.

  6. Expression and biological-clinical significance of hTR, hTERT and CKS2 in washing fluids of patients with bladder cancer

    Directory of Open Access Journals (Sweden)

    Talesa Vincenzo N

    2010-10-01

    Full Text Available Abstract Background at present, pathogenesis of bladder cancer (BC has not been fully elucidated. Aim of this study is to investigate the role of human telomerase RNA (hTR, human telomerase reverse transcriptase (hTERT and CDC28 protein kinase regulatory subunit 2 (CKS2 in bladder carcinogenesis and their possible clinical significance; Methods the transcript levels of hTR, hTERT and CKS2 were quantified by Real time reverse transcriptase chain reaction in exfoliated cells from bladder washings of 36 patients with BC and 58 controls. The statistical significance of differences between BC bearing patients and control groups, in the general as well as in the stratified analysis (superficial or invasive BC, was assessed by Student's t test. Non parametric Receiver Operating Characteristics analysis (ROC was performed to ascertain the accuracy of study variables to discriminate between BC and controls. The clinical value of concomitant examination of hTR, hTERT and CKS2 was evaluated by logistic regression analysis; Results a significant decrease in hTR and a significant increase in hTERT or CKS2 gene expression were found between BC bearing patients and controls, as well as in the subgroups analysis. The area under the curve (AUC indicated an average discrimination power for the three genes, both in the general and subgroups analysis, when singularly considered. The ability to significantly discriminate between superficial and invasive BC was observed only for hTR transcript levels. A combined model including hTR and CKS2 was the best one in BC diagnosis; Conclusions our results, obtained from a sample set particularly rich of exfoliated cells, provide further molecular evidence on the involvement of hTR, hTERT and CKS2 gene expression in BC carcinogenesis. In particular, while hTERT and CKS2 gene expression seems to have a major involvement in the early stages of the disease, hTR gene expression, seems to be more involved in progression. In

  7. Functionalized porous silica&maghemite core-shell nanoparticles for applications in medicine: design, synthesis and immunotoxicity

    Czech Academy of Sciences Publication Activity Database

    Zasońska, Beata Anna; Líšková, A.; Kuricová, M.; Tulinská, J.; Pop-Georgievski, Ognen; Čiampor, F.; Vávra, I.; Dušinská, M.; Ilavská, S.; Horváthová, M.; Horák, Daniel

    2016-01-01

    Roč. 57, č. 2 (2016), s. 165-178 ISSN 0353-9504 R&D Projects: GA ČR(CZ) GC16-01128J Institutional support: RVO:61389013 Keywords : core-shell maghemite nanoparticles * proliferative activity of lymphocytes * phagocytic activity Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.619, year: 2016 http://www.cmj.hr/2016/57/2/27106358.htm

  8. HYDRATE CORE DRILLING TESTS

    Energy Technology Data Exchange (ETDEWEB)

    John H. Cohen; Thomas E. Williams; Ali G. Kadaster; Bill V. Liddell

    2002-11-01

    The ''Methane Hydrate Production from Alaskan Permafrost'' project is a three-year endeavor being conducted by Maurer Technology Inc. (MTI), Noble, and Anadarko Petroleum, in partnership with the U.S. DOE National Energy Technology Laboratory (NETL). The project's goal is to build on previous and ongoing R&D in the area of onshore hydrate deposition. The project team plans to design and implement a program to safely and economically drill, core and produce gas from arctic hydrates. The current work scope includes drilling and coring one well on Anadarko leases in FY 2003 during the winter drilling season. A specially built on-site core analysis laboratory will be used to determine some of the physical characteristics of the hydrates and surrounding rock. Prior to going to the field, the project team designed and conducted a controlled series of coring tests for simulating coring of hydrate formations. A variety of equipment and procedures were tested and modified to develop a practical solution for this special application. This Topical Report summarizes these coring tests. A special facility was designed and installed at MTI's Drilling Research Center (DRC) in Houston and used to conduct coring tests. Equipment and procedures were tested by cutting cores from frozen mixtures of sand and water supported by casing and designed to simulate hydrate formations. Tests were conducted with chilled drilling fluids. Tests showed that frozen core can be washed out and reduced in size by the action of the drilling fluid. Washing of the core by the drilling fluid caused a reduction in core diameter, making core recovery very difficult (if not impossible). One successful solution was to drill the last 6 inches of core dry (without fluid circulation). These tests demonstrated that it will be difficult to capture core when drilling in permafrost or hydrates without implementing certain safeguards. Among the coring tests was a simulated hydrate

  9. Core-shell nanoparticles optical sensors - Rational design of zinc ions fluorescent nanoprobes of improved analytical performance

    Science.gov (United States)

    Woźnica, Emilia; Gasik, Joanna; Kłucińska, Katarzyna; Kisiel, Anna; Maksymiuk, Krzysztof; Michalska, Agata

    2017-10-01

    In this work the effect of affinity of an analyte to a receptor on the response of nanostructural fluorimetric probes is discussed. Core-shell nanoparticles sensors are prepared that benefit from the properties of the phases involved leading to improved analytical performance. The optical transduction system chosen is independent of pH, thus the change of sample pH can be used to control the analyte - receptor affinity through the "conditional" binding constant prevailing within the lipophilic phase. It is shown that by affecting the "conditional" binding constant the performance of the sensor can be fine-tuned. As expected, increase in "conditional" affinity of the ligand embedded in the lipophilic phase to the analyte results in higher sensitivity over narrow concentration range - bulk reaction and sigmoidal shape response of emission intensity vs. logarithm of concentration changes. To induce a linear dependence of emission intensity vs. logarithm of analyte concentration covering a broad concentration range, a spatial confinement of the reaction zone is proposed, and application of core-shell nanostructures. The core material, polypyrrole nanospheres, is effectively not permeable for the analyte - ligand complex, thus the reaction is limited to the outer shell layer of the polymer prepared from poly(maleic anhydride-alt-1-octadecene). For herein introduced system a linear dependence of emission intensity vs. logarithm of Zn2+ concentration was obtained within the range from 10-7 to 10-1 M.

  10. NSGA-II Algorithm with a Local Search Strategy for Multiobjective Optimal Design of Dry-Type Air-Core Reactor

    Directory of Open Access Journals (Sweden)

    Chengfen Zhang

    2015-01-01

    Full Text Available Dry-type air-core reactor is now widely applied in electrical power distribution systems, for which the optimization design is a crucial issue. In the optimization design problem of dry-type air-core reactor, the objectives of minimizing the production cost and minimizing the operation cost are both important. In this paper, a multiobjective optimal model is established considering simultaneously the two objectives of minimizing the production cost and minimizing the operation cost. To solve the multi-objective optimization problem, a memetic evolutionary algorithm is proposed, which combines elitist nondominated sorting genetic algorithm version II (NSGA-II with a local search strategy based on the covariance matrix adaptation evolution strategy (CMA-ES. NSGA-II can provide decision maker with flexible choices among the different trade-off solutions, while the local-search strategy, which is applied to nondominated individuals randomly selected from the current population in a given generation and quantity, can accelerate the convergence speed. Furthermore, another modification is that an external archive is set in the proposed algorithm for increasing the evolutionary efficiency. The proposed algorithm is tested on a dry-type air-core reactor made of rectangular cross-section litz-wire. Simulation results show that the proposed algorithm has high efficiency and it converges to a better Pareto front.

  11. Lead users' ideas on core features to support physical activity in rheumatoid arthritis: a first step in the development of an internet service using participatory design.

    Science.gov (United States)

    Revenäs, Åsa; Opava, Christina H; Åsenlöf, Pernilla

    2014-03-22

    Despite the growing evidence of the benefits of physical activity (PA) in individuals with rheumatoid arthritis (RA), the majority is not physically active enough. An innovative strategy is to engage lead users in the development of PA interventions provided over the internet. The aim was to explore lead users' ideas and prioritization of core features in a future internet service targeting adoption and maintenance of healthy PA in people with RA. Six focus group interviews were performed with a purposively selected sample of 26 individuals with RA. Data were analyzed with qualitative content analysis and quantification of participants' prioritization of most important content. Six categories were identified as core features for a future internet service: up-to-date and evidence-based information and instructions, self-regulation tools, social interaction, personalized set-up, attractive design and content, and access to the internet service. The categories represented four themes, or core aspects, important to consider in the design of the future service: (1) content, (2) customized options, (3) user interface and (4) access and implementation. This is, to the best of our knowledge, the first study involving people with RA in the development of an internet service to support the adoption and maintenance of PA.Participants helped identifying core features and aspects important to consider and further explore during the next phase of development. We hypothesize that involvement of lead users will make transfer from theory to service more adequate and user-friendly and therefore will be an effective mean to facilitate PA behavior change.

  12. Failure Predictions for Graphite Reflector Bricks in the Very High Temperature Reactor with the Prismatic Core Design

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Gyanender, E-mail: sing0550@umn.edu [Department of Mechanical Engineering, University of Minnesota, 111, Church St. SE, Minneapolis, MN 55455 (United States); Fok, Alex [Minnesota Dental Research in Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, 515, Delaware St. SE, Minneapolis, MN 55455 (United States); Department of Mechanical Engineering, University of Minnesota, 111, Church St. SE, Minneapolis, MN 55455 (United States); Mantell, Susan [Department of Mechanical Engineering, University of Minnesota, 111, Church St. SE, Minneapolis, MN 55455 (United States)

    2017-06-15

    Highlights: • Failure probability of VHTR reflector bricks predicted though crack modeling. • Criterion chosen for defining failure strongly affects the predictions. • Breaching of the CRC could be significantly delayed through crack arrest. • Capability to predict crack initiation and propagation demonstrated. - Abstract: Graphite is used in nuclear reactor cores as a neutron moderator, reflector and structural material. The dimensions and physical properties of graphite change when it is exposed to neutron irradiation. The non-uniform changes in the dimensions and physical properties lead to the build-up of stresses over the course of time in the core components. When the stresses reach the critical limit, i.e. the strength of the material, cracking occurs and ultimately the components fail. In this paper, an explicit crack modeling approach to predict the probability of failure of a VHTR prismatic reactor core reflector brick is presented. Firstly, a constitutive model for graphite is constructed and used to predict the stress distribution in the reflector brick under in-reactor conditions of high temperature and irradiation. Fracture simulations are performed as part of a Monte Carlo analysis to predict the probability of failure. Failure probability is determined based on two different criteria for defining failure time: A) crack initiation and B) crack extension to near control rod channel. A significant difference is found between the failure probabilities based on the two criteria. It is predicted that the reflector bricks will start cracking during the time range of 5–9 years, while breaching of the control rod channels will occur during the period of 11–16 years. The results show that, due to crack arrest, there is a significantly delay between crack initiation and breaching of the control rod channel.

  13. Transitions, Risks, and Actions in Coronary Events--Center for Outcomes Research and Education (TRACE-CORE): design and rationale.

    Science.gov (United States)

    Waring, Molly E; McManus, Richard H; Saczynski, Jane S; Anatchkova, Milena D; McManus, David D; Devereaux, Randolph S; Goldberg, Robert J; Allison, Jeroan J; Kiefe, Catarina I

    2012-09-01

    Cardiovascular disease continues to cause significant morbidity, mortality, and impaired quality of life, with unrealized health gains from the underuse of available evidence. The Transitions, Risks, and Actions in Coronary Events Center for Outcomes Research and Education (TRACE-CORE) aims to advance the science of acute coronary syndromes by examining the determinants and outcomes of the quality of transition from hospital to community and by quantifying the impact of potentially modifiable characteristics associated with decreased quality of life, rehospitalization, and mortality. TRACE-CORE comprises a longitudinal multiracial cohort of patients hospitalized with acute coronary syndromes, 2 research projects, and development of a nucleus of early stage investigators. We are currently enrolling 2500 adults hospitalized for acute coronary syndromes at 6 hospitals in the northeastern and southeastern United States. We will follow these patients for 24 months after hospitalization through medical record abstraction and 5 patient interviews focusing on quality of life, cardiac events, rehospitalizations, mortality, and medical, behavioral, and psychosocial characteristics. The Transitions Project studies determinants of and disparities in outcomes of the quality of patients' transition from hospital to community. Focusing on potentially modifiable factors, the Action Scores Project will develop and validate action scores to predict recurrent cardiac events, death, and quality of life, describe longitudinal variation in these scores, and develop a dashboard for patient and provider action on the basis of these scores. In TRACE-CORE, sound methodologic principles of observational studies converge with outcomes and effectiveness research approaches. We expect that our data, research infrastructure, and research projects will inform the development of novel secondary prevention approaches and underpin the careers of cardiovascular outcomes researchers.

  14. Differential effect of DDT, DDE, and DDD on COX-2 expression in the human trophoblast derived HTR-8/SVneo cells.

    Science.gov (United States)

    Dominguez-Lopez, Pablo; Diaz-Cueto, Laura; Olivares, Aleida; Ulloa-Aguirre, Alfredo; Arechavaleta-Velasco, Fabian

    2012-11-01

    The purpose of this study was to investigate the effect of 1,1,1-trichloro-2,2-bis-(chlorophenyl)ethane (DDT), 1,1-bis-(chlorophenyl)-2,2-dichloroethene (DDE), and 1,1-dichloro-2,2-bis(chlorophenyl)ethane (DDD) isomers on COX-2 expression in a human trophoblast-derived cell line. Cultured HTR-8/SVneo trophoblast cells were exposed to DDT isomers and its metabolites for 24 h, and COX-2 mRNA and protein expression were assessed by RT-PCR, Western blotting, and ELISA. Prostaglandin E₂ production was also measured by ELISA. Both COX-2 mRNA and protein were detected under control (unexposed) conditions in the HTR-8/SVneo cell line. COX-2 protein expression and prostaglandin E₂ production but not COX-2 mRNA levels increased only after DDE and DDD isomers exposure. It is concluded that DDE and DDD exposure induce the expression of COX-2 protein, leading to increased prostaglandin E2 production. Interestingly, the regulation of COX-2 by these organochlorines pesticides appears to be at the translational level. © 2012 Wiley Periodicals, Inc.

  15. Inhibitors of Helicobacter pylori protease HtrA found by 'virtual ligand' screening combat bacterial invasion of epithelia.

    Directory of Open Access Journals (Sweden)

    Martin Löwer

    Full Text Available BACKGROUND: The human pathogen Helicobacter pylori (H. pylori is a main cause for gastric inflammation and cancer. Increasing bacterial resistance against antibiotics demands for innovative strategies for therapeutic intervention. METHODOLOGY/PRINCIPAL FINDINGS: We present a method for structure-based virtual screening that is based on the comprehensive prediction of ligand binding sites on a protein model and automated construction of a ligand-receptor interaction map. Pharmacophoric features of the map are clustered and transformed in a correlation vector ('virtual ligand' for rapid virtual screening of compound databases. This computer-based technique was validated for 18 different targets of pharmaceutical interest in a retrospective screening experiment. Prospective screening for inhibitory agents was performed for the protease HtrA from the human pathogen H. pylori using a homology model of the target protein. Among 22 tested compounds six block E-cadherin cleavage by HtrA in vitro and result in reduced scattering and wound healing of gastric epithelial cells, thereby preventing bacterial infiltration of the epithelium. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that receptor-based virtual screening with a permissive ('fuzzy' pharmacophore model can help identify small bioactive agents for combating bacterial infection.

  16. Core-shell designs of photoluminescent nanodiamonds with porous silica coatings for bioimaging and drug delivery II: application.

    Science.gov (United States)

    Prabhakar, Neeraj; Näreoja, Tuomas; von Haartman, Eva; Karaman, Didem Şen; Jiang, Hua; Koho, Sami; Dolenko, Tatiana A; Hänninen, Pekka E; Vlasov, Denis I; Ralchenko, Victor G; Hosomi, Satoru; Vlasov, Igor I; Sahlgren, Cecilia; Rosenholm, Jessica M

    2013-05-07

    Recent advances within materials science and its interdisciplinary applications in biomedicine have emphasized the potential of using a single multifunctional composite material for concurrent drug delivery and biomedical imaging. Here we present a novel composite material consisting of a photoluminescent nanodiamond (ND) core with a porous silica (SiO2) shell. This novel multifunctional probe serves as an alternative nanomaterial to address the existing problems with delivery and subsequent tracing of the particles. Whereas the unique optical properties of ND allows for long-term live cell imaging and tracking of cellular processes, mesoporous silica nanoparticles (MSNs) have proven to be efficient drug carriers. The advantages of both ND and MSNs were hereby integrated in the new composite material, ND@MSN. The optical properties provided by the ND core rendered the nanocomposite suitable for microscopy imaging in fluorescence and reflectance mode, as well as super-resolution microscopy as a STED label; whereas the porous silica coating provided efficient intracellular delivery capacity, especially in surface-functionalized form. This study serves as a demonstration how this novel nanomaterial can be exploited for both bioimaging and drug delivery for future theranostic applications.

  17. Fuel and Core Design Options to Overcome the Heavy Metal Loading Limit and Improve Performance and Safety of Liquid Salt Cooled Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, Bojan [Georgia Inst. of Technology, Atlanta, GA (United States); Maldonado, Ivan [Univ. of Tennessee, Knoxville, TN (United States)

    2016-04-14

    The research performed in this project addressed the issue of low heavy metal loading and the resulting reduced cycle length with increased refueling frequency, inherent to all FHR designs with solid, non-movable fuel based on TRISO particles. Studies performed here focused on AHTR type of reactor design with plate (“plank”) fuel. Proposal to FY12 NEUP entitled “Fuel and Core Design Options to Overcome the Heavy Metal Loading Limit and Improve Performance and Safety of Liquid Salt Cooled Reactors” was selected for award, and the 3-year project started in August 2012. A 4-month NCE was granted and the project completed on December 31, 2015. The project was performed by Georgia Tech (Prof. Bojan Petrovic, PI) and University of Tennessee (Prof. Ivan Maldonado, Co-PI), with a total funding of $758,000 over 3 years. In addition to two Co-PIs, the project directly engaged 6 graduate students (at doctoral or MS level) and 2 postdoctoral researchers. Additionally, through senior design projects and graduate advanced design projects, another 23 undergraduate and 12 graduate students were exposed to and trained in the salt reactor technology. We see this as one of the important indicators of the project’s success and effectiveness. In the process, 1 journal article was published (with 3 journal articles in preparation), together with 8 peer-reviewed full conference papers, 8 peer-reviewed extended abstracts, as well as 1 doctoral dissertation and 2 master theses. The work included both development of models and methodologies needed to adequately analyze this type of reactor, fuel, and its fuel cycle, as well as extensive analyses and optimization of the fuel and core design.

  18. Design of elliptical-core mode-selective photonic lanterns with six modes for MIMO-free mode division multiplexing systems.

    Science.gov (United States)

    Sai, Xiaowei; Li, Yan; Yang, Chen; Li, Wei; Qiu, Jifang; Hong, Xiaobin; Zuo, Yong; Guo, Hongxiang; Tong, Weijun; Wu, Jian

    2017-11-01

    Elliptical-core few mode fiber (EC-FMF) is used in a mode division multiplexing (MDM) transmission system to release multiple-input-multiple-output (MIMO) digital-signal-processing, which reduces the cost and the complexity of the receiver. However, EC-FMF does not match with conventional multiplexers/de-multiplexers (MUXs/DeMUXs) such as a photonic lantern, leading to extra mode coupling loss and crosstalk. We design elliptical-core mode-selective photonic lanterns (EC-MSPLs) with six modes, which can match well with EC-FMF in MIMO-free MDM systems. Simulation of the EC-MSPL using the beam propagation method was demonstrated employing a combination of either step-index or graded-index fibers with six different sizes of cores, and the taper transition length of 8 cm or 4 cm. Through numerical simulations and optimizations, both types of photonic lanterns can realize low loss transmission and low crosstalk of below -20.0  dB for all modes.

  19. Applying Topological and Economical Principles in Catalyst Design: New Alumina-​Cobalt Core-​Shell Catalysts

    NARCIS (Netherlands)

    Calderone, V.R.; Shiju, N.R.; Curulla Ferré, D.; Rose, A.; Thiessen, J.; Jess, A.; van der Roest, E.; Wiewel, B.V.; Rothenberg, G.

    2014-01-01

    Designing new and effective catalysts may be an art, but its consequences are very real and pragmatic. That said, chemists often build designs on ideal systems, whereas the manufg. of chems. requires catalysts that withstand varied feeds, harsh conditions and long exposure times. Moreover,

  20. Investigating Implemented Process Design: A Case Study on the Impact of Process-aware Information Systems on Core Job Dimensions

    NARCIS (Netherlands)

    Mutschler, B.B.; Rijpkema, M.; Reichert, M.U.

    Adequate process design particularly means that a process fulfills its stakeholders’ expectations. However, when designing process-aware information systems (PAIS), one stakeholder and his expectations are often neglected: the end user. Frequently, this results in end user fears, which, in turn,

  1. Ice cores

    DEFF Research Database (Denmark)

    Svensson, Anders

    2014-01-01

    Ice cores from Antarctica, from Greenland, and from a number of smaller glaciers around the world yield a wealth of information on past climates and environments. Ice cores offer unique records on past temperatures, atmospheric composition (including greenhouse gases), volcanism, solar activity......, dustiness, and biomass burning, among others. In Antarctica, ice cores extend back more than 800,000 years before present (Jouzel et al. 2007), whereas. Greenland ice cores cover the last 130,000 years...

  2. VENUS: cold prototype installation of the head-end of the reprocessing of HTR fuel elements. Activity report, 1 July 1976--31 December 1976

    Energy Technology Data Exchange (ETDEWEB)

    Boehnert, R.; Walter, C.

    1977-02-15

    The purpose of the VENUS Project is advance planning for the construction of a cold prototype system to incinerate HTR fuel element graphite. The Venus Project is organized into four phases between advance planning and experimental operation, corresponding to the maturity of the work. It is in the advance planning phase. Status of individual studies is given. (LK)

  3. Streptococcus pneumoniae serine protease HtrA, but not SFP or PrtA, is a major virulence factor in pneumonia

    NARCIS (Netherlands)

    de Stoppelaar, Sacha F.; Bootsma, Hester J.; Zomer, Aldert; Roelofs, Joris J. T. H.; Hermans, Peter W. M.; van 't Veer, Cornelis; van der Poll, Tom

    2013-01-01

    Streptococcus (S.) pneumoniae is a common causative pathogen in pneumonia. Serine protease orthologs expressed by a variety of bacteria have been found of importance for virulence. Previous studies have identified two serine proteases in S. pneumoniae, HtrA (high-temperature requirement A) and PrtA

  4. Design Study for a Low-Enriched Uranium Core for the High Flux Isotope Reactor, Annual report for FY 2009

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, David [ORNL; Freels, James D [ORNL; Ilas, Germina [ORNL; Miller, James Henry [ORNL; Primm, Trent [ORNL; Sease, John D [ORNL; Guida, Tracey [University of Pittsburgh; Jolly, Brian C [ORNL

    2010-02-01

    This report documents progress made during FY 2009 in studies of converting the High Flux Isotope Reactor (HFIR) from high enriched uranium (HEU) fuel to low enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum alloy. With axial and radial grading of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in reactor performance from the current level. Results of selected benchmark studies imply that calculations of LEU performance are accurate. Studies are reported of the application of a silicon coating to surrogates for spheres of uranium-molybdenum alloy. A discussion of difficulties with preparing a fuel specification for the uranium-molybdenum alloy is provided. A description of the progress in developing a finite element thermal hydraulics model of the LEU core is provided.

  5. Design and characterization of core-shell mPEG-PLGA composite microparticles for development of cell-scaffold constructs

    DEFF Research Database (Denmark)

    Wen, Yanhong; Gallego, Monica Ramos; Nielsen, Lene Feldskov

    2013-01-01

    Appropriate scaffolds capable of providing suitable biological and structural guidance are of great importance to generate cell-scaffold constructs for cell-based tissue engineering. The aim of the present study was to develop composite microparticles with a structure to provide functionality...... as a combined drug delivery/scaffold system. Composite microparticles were produced by incorporating either alginate/dermatan sulfate (Alg/DS) or alginate/chitosan/dermatan sulfate (Alg/CS/DS) particles in mPEG-PLGA microparticles using coaxial ultrasonic atomization. The encapsulation and distribution of Alg....../DS or Alg/CS/DS particles in the mPEG-PLGA microparticles were significantly dependent on the operating conditions, including the flow rate ratio (Qout/Qin) and the viscosity of the polymer solutions (Vout, Vin) between the outer and the inner feeding channels. The core-shell composite microparticles...

  6. The Role of 5-HTR6 in Mossy Fiber Sprouting: Activating Fyn and p-ERK1/2 in Pilocarpine-Induced Chronic Epileptic Rats

    Directory of Open Access Journals (Sweden)

    Wanhui Lin

    2017-05-01

    Full Text Available Objective: Our primary objective is to verify whether 5-HTR6 is involved in the development of mossy fiber sprouting (MFS, and to determine how the progression of MFS is affected by 5-HTR6. Methods: A total of 90 male adult Sprague-Dawley rats were allocated into either the control group (n=36 or the epileptic group (n=54. Status epilepticus (SE of rats was induced by the intraperitoneal (i.p. injection of LiCl-pilocarpine. We conducted our experiments in two stages. The first stage involves equally dividing 36 epileptic rats into three groups with treatments of none, 5-HTR6 antagonist SB-27104 (SB and vehicle DMSO. Then behavior and electroencephalogram (EEG of rats were monitored by video-EEG. The second stage involves dividing 126 epileptic rats into seven groups with treatments of none, 10% DMSO, SB (100 µg/kg, Fyn antagonist PP2 (50 µg/kg, p-ERK1/2 antagonist PD-98059 (30 µg/kg, SB (100 µg/ kg + PP2 (50 µg/kg; SB (100 µg/kg + PD-98059 (30 µg/kg. We also treated 18 rats in the control group of the first stage with 100 µg/kg 5-HTR6 agonist WAY-181187 (WAY. MFS of rats was detected through the approach of Timm’s staining. Finally, expressions of 5-HTR6, Fyn, p-ERK1/2 and GAP-3 were qualified and semi-quantified via western blotting or RT-PCR. Results: Induction of SE could stimulate formation of MFS and increased GAP-43 expressions. Expressions of 5-HTR6, Fyn and p-ERK1/2 were also up-regulated with increasing time after establishment of SE models. The development of MFS was remarkably inhibited by SB, PP2 and PD. Compared to the single antagonist, such an inhibitory effect was enhanced by SB+PD or SB+PP. Moreover, treatment of healthy rats with WAY would contribute to up-regulated Fyn and p-ERK1/2 expressions, as well as development of MFS (P < 0.05. Suppression of Fyn triggered a down-regulating trend of p-ERK1/2 (P < 0.05, however, suppressed p-ERK1/2 did not have such a significant effect on Fyn expression. Conclusion: HTR6 may

  7. Prolonged Activation of the Htr2b Serotonin Receptor Impairs Glucose Stimulated Insulin Secretion and Mitochondrial Function in MIN6 Cells.

    Science.gov (United States)

    Cataldo, Luis Rodrigo; Mizgier, María L; Bravo Sagua, Roberto; Jaña, Fabián; Cárdenas, César; Llanos, Paola; Busso, Dolores; Olmos, Pablo; Galgani, José E; Santos, José L; Cortés, Víctor A

    2017-01-01

    Pancreatic β-cells synthesize and release serotonin (5 hydroxytryptamine, 5HT); however, the role of 5HT receptors on glucose stimulated insulin secretion (GSIS) and the mechanisms mediating this function is not fully understood. The aims of this study were to determine the expression profile of 5HT receptors in murine MIN6 β-cells and to examine the effects of pharmacological activation of 5HT receptor Htr2b on GSIS and mitochondrial function. mRNA levels of 5HT receptors in MIN6 cells were quantified by RT qPCR. GSIS was assessed in MIN6 cells in response to global serotonergic activation with 5HT and pharmacological Htr2b activation or inhibition with BW723C86 or SB204741, respectively. In response to Htr2b activation also was evaluated the mRNA and protein levels of PGC1α and PPARy by RT-qPCR and western blotting and mitochondrial function by oxygen consumption rate (OCR) and ATP cellular content. We found that mRNA levels of most 5HT receptors were either very low or undetectable in MIN6 cells. By contrast, Htr2b mRNA was present at moderate levels in these cells. Preincubation (6 h) of MIN6 cells with 5HT or BW723C86 reduced GSIS and the effect of 5HT was prevented by SB204741. Preincubation with BW723C86 increased PGC1α and PPARy mRNA and protein levels and decreased mitochondrial respiration and ATP content in MIN6 cells. Our results indicate that prolonged Htr2b activation in murine β-cells decreases glucose-stimulated insulin secretion and mitochondrial activity by mechanisms likely dependent on enhanced PGC1α/PPARy expression.

  8. Influence of remaining coronal structure and of the marginal design on the fracture strength of roots restored with cast post and core.

    Science.gov (United States)

    Carlini-Júnior, Bruno; Cecchin, Doglas; Farina, Ana P; Pereira, Gisele D S; Prieto, Lúcia T; Paulillo, Luis A M S

    2013-01-01

    The purpose of this study was to evaluate the fracture strength of roots that were prosthetically restored with cast post and core with or without any remaining coronal structure and with different finish lines. Sixty bovine incisors were sectioned below the cementoenamel junction, endodontically treated and randomly divided into six experimental groups (n = 10) containing teeth with or without any remaining coronal structure and with a beveled shoulder, a chanfered or a shoulder finish line design. The cast post and core were luted with dual-cured resin cement. The metal crowns were cemented with zinc phosphate cement. The specimens were subjected to a tangential compressive load (135° angle) at a crosshead speed of 0.5 mm/min until failure, using a universal testing machine. The fracture strength data were analyzed using the ANOVA and LSMeans (least square means) tests (α = 0.05). The data indicated that the teeth with 2 mm of remaining coronal structure showed the highest fracture strength values when compared with the teeth without any remaining structure (p strength values were obtained for the beveled shoulder, followed by the chanfered and then by the shoulder designs (p strength, a beveled shoulder and 2 mm of remaining coronal structure are the ideal conditions.

  9. Rational design of core-shell molecularly imprinted polymer based on computational simulation and Doehlert experimental optimization: application to the separation of tanshinone IIA from Salvia miltiorrhiza Bunge.

    Science.gov (United States)

    Jia, Xianjun; Li, Hong; Luo, Jing; Lu, Qing; Peng, Yan; Shi, Liying; Liu, Liping; Du, Shuhu; Zhang, Guijun; Chen, Lina

    2012-07-01

    Computational simulation and Doehlert experimental optimization were done for the rational design of a core-shell molecularly imprinted polymer (CS-MIP) for use in the highly selective separation of Tanshinone IIA (TSIIA) from the crude extracts of Salvia miltiorrhiza Bunge (SMB). The functional monomer layer of the polymer shells directed the selective occurrence of imprinting polymerization at the surface of silica through the copolymerization of vinyl end groups with functional monomers and also drove TSIIA templates into the formed polymer shells through the charge-transfer complex interactions between TSIIA and the functional monomer layer. As a result, the maximum rebinding capacity was achieved with the use of optimal grafting ratio by the Doehlert design. The CS-MIP exhibited high recognition selectivity and binding affinity to TSIIA. When the imprinted particles were used as dispersive solid phase extraction sorbents, the recovery yield of TSIIA reached 93% by a one-step extraction from the crude extracts of SMB, and the purity of TSIIA was larger than 98% by HPLC analysis. These results show the possibility of a highly selective separation and enrichment of TSIIA from the SMB using the TSIIA-imprinted core-shell molecularly imprinted polymers.

  10. The fast-spectrum transmutation experimental facility FASTEF: Main design achievements (Part 1: Core and primary system) within the FP7-CDT collaborative project of the European Commission

    Energy Technology Data Exchange (ETDEWEB)

    De Bruyn, D.; Fernandez, R. [Belgian Nuclear Research Centre (SCK CEN), Boeretang 200, 2400 Mol (Belgium); Mansani, L. [ANSALDO, Corso Perrone 25, 16152 Genova (Italy); Woaye-Hune, A. [AREVA-NP, rue Juliette Recamier 10, 69456 Lyon Cedex 06 (France); Sarotto, M. [ENEA, Via Martiri di Monte Sole 4, 40129 Bologna (Italy); Bubelis, E. [KIT, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2012-07-01

    MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is the flexible experimental accelerator-driven system (ADS) in development at SCK CEN in replacement of its material testing reactor BR2. SCK CEN in association with 17 European partners from industry, research centres and academia, responded to the FP7 (Seventh Framework Programme) call from the European Commission to establish a Central Design Team (CDT) for the design of a Fast Spectrum Transmutation Experimental Facility (FASTEF) able to demonstrate efficient transmutation and associated technology through a system working in subcritical and/or critical mode. The project has started on April 01, 2009 for a period of three years. In this paper, we present the latest configuration of the reactor core and primary system. The FASTEF facility has evolved quite a lot since the intermediate reporting done at the ICAPP'10 and ICAPP'11 conferences 1 2. If it remains a small-scale facility, the core power amounts now up to 100 MWth in critical mode. In a companion paper 3, we present the concept of the reactor building and the plant layout. (authors)

  11. Preparation, Characterization, and Optimization of Folic Acid-Chitosan-Methotrexate Core-Shell Nanoparticles by Box-Behnken Design for Tumor-Targeted Drug Delivery.

    Science.gov (United States)

    Naghibi Beidokhti, Hamid Reza; Ghaffarzadegan, Reza; Mirzakhanlouei, Sasan; Ghazizadeh, Leila; Dorkoosh, Farid Abedin

    2017-01-01

    The objective of this study was to investigate the combined influence of independent variables in the preparation of folic acid-chitosan-methotrexate nanoparticles (FA-Chi-MTX NPs). These NPs were designed and prepared for targeted drug delivery in tumor. The NPs of each batch were prepared by coaxial electrospray atomization method and evaluated for particle size (PS) and particle size distribution (PSD). The independent variables were selected to be concentration of FA-chitosan, ratio of shell solution flow rate to core solution flow rate, and applied voltage. The process design of experiments (DOE) was obtained with three factors in three levels by Design expert software. Box-Behnken design was used to select 15 batches of experiments randomly. The chemical structure of FA-chitosan was examined by FTIR. The NPs of each batch were collected separately, and morphologies of NPs were investigated by field emission scanning electron microscope (FE-SEM). The captured pictures of all batches were analyzed by ImageJ software. Mean PS and PSD were calculated for each batch. Polynomial equation was produced for each response. The FE-SEM results showed the mean diameter of the core-shell NPs was around 304 nm, and nearly 30% of the produced NPs are in the desirable range. Optimum formulations were selected. The validation of DOE optimization results showed errors around 2.5 and 2.3% for PS and PSD, respectively. Moreover, the feasibility of using prepared NPs to target tumor extracellular pH was shown, as drug release was greater in the pH of endosome (acidic medium). Finally, our results proved that FA-Chi-MTX NPs were active against the human epithelial cervical cancer (HeLa) cells.

  12. Multifunctional superparamagnetic fe3O4@SiO2 core/shell nanoparticles: design and application for cell imaging.

    Science.gov (United States)

    Zhao, Xueling; Zhao, Hongli; Yuan, Huihui; Lan, Minbo

    2014-02-01

    Highly biocompatible sub-50-nm monodisperse superparamagnetic Fe3O4@SiO2 core/shell nanoparticles with luminescent silica shells were synthesized by a w/o-microemulsion technique. And then these nanoparticles were coated with the covalently bonded biocompatible polymer poly(ethylene glycol) (PEG) and modified with the biological cancer targeting ligand folic acid (FA). After characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier transformed infrared spectroscopy (FT-IR), Thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), UV-vis, fluorescence spectroscopy and confocal laser scanning microscopy (CLSM), we confirmed that Fe3O4@SiO2 (FITC)-PEG-FA nanocomposites (SMNPs-FA) could be efficiently taken up by HeLa cancer cells and KB cells which are of over-expression of folate receptors. The multifunctional nanomaterials exhibited superparamagnetic, monodisperse, highly biocompatible, intensively fluorescent and capable of recognizing and binding cells that overexpress folate receptors, which would be useful for targeting cell imaging and provide an excellent platform for further development of an efficient cancer therapy.

  13. Preliminary Conceptual Design and Development of Core Technology of Very High Temperature Gas-Cooled Reactor Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Jong Hwa; Kang, H. S.; Gil, C. S. and others

    2006-05-15

    For the nuclear hydrogen production system, the VHTR technology and the IS cycle technology are being developed. A comparative evaluation on the block type reactor and the pebble type reactor is performed to decide a proper nuclear hydrogen production reactor. 100MWt prismatic type reactor is tentatively decided and its safety characteristics are roughly investigated. Computation codes of nuclear design, thermo-fluid design, safety-performance analysis are developed and verified. Also, the development of a risk informed design technology is started. Experiments for metallic materials and graphites are carried out for the selection of materials of VHTR components. Diverse materials for process heat exchanger are studied in various corrosive environments. Pyrolytic carbon and SiC coating technology is developed and fuel manufacturing technology is basically established. Computer program is developed to evaluate the performance of coated particle fuels.

  14. An Overview of Demise Calculations, Conceptual Design Studies, and Hydrazine Compatibility Testing for the GPM Core Spacecraft Propellant Tank

    Science.gov (United States)

    Estes, Robert H.; Moore, N. R.

    2007-01-01

    NASA's Global Precipitation Measurement (GPM) mission is an ongoing Goddard Space Flight Center (GSFC) project whose basic objective is to improve global precipitation measurements. It has been decided that the GPM spacecraft is to be a "design for demise" spacecraft. This requirement resulted in the need for a propellant tank that would also demise or ablate to an appropriate degree upon re-entry. This paper will describe GSFC-performed spacecraft and tankage demise analyses, vendor conceptual design studies, and vendor performed hydrazine compatibility and wettability tests performed on 6061 and 2219 aluminum alloys.

  15. Reactor Physics Methods and Preconceptual Core Design Analyses for Conversion of the Advanced Test Reactor to Low-Enriched Uranium Fuel Annual Report for Fiscal Year 2012

    Energy Technology Data Exchange (ETDEWEB)

    David W. Nigg; Sean R. Morrell

    2012-09-01

    Under the current long-term DOE policy and planning scenario, both the ATR and the ATRC will be reconfigured at an appropriate time within the next several years to operate with low-enriched uranium (LEU) fuel. This will be accomplished under the auspices of the Reduced Enrichment Research and Test Reactor (RERTR) Program, administered by the DOE National Nuclear Security Administration (NNSA). At a minimum, the internal design and composition of the fuel element plates and support structure will change, to accommodate the need for low enrichment in a manner that maintains total core excess reactivity at a suitable level for anticipated operational needs throughout each cycle while respecting all control and shutdown margin requirements and power distribution limits. The complete engineering design and optimization of LEU cores for the ATR and the ATRC will require significant multi-year efforts in the areas of fuel design, development and testing, as well as a complete re-analysis of the relevant reactor physics parameters for a core composed of LEU fuel, with possible control system modifications. Ultimately, revalidation of the computational physics parameters per applicable national and international standards against data from experimental measurements for prototypes of the new ATR and ATRC core designs will also be required for Safety Analysis Report (SAR) changes to support routine operations with LEU. This report is focused on reactor physics analyses conducted during Fiscal Year (FY) 2012 to support the initial development of several potential preconceptual fuel element designs that are suitable candidates for further study and refinement during FY-2013 and beyond. In a separate, but related, effort in the general area of computational support for ATR operations, the Idaho National Laboratory (INL) is conducting a focused multiyear effort to introduce modern high-fidelity computational reactor physics software and associated validation protocols to replace

  16. Collaboration by Design: Integrating Core Pedagogical Content and Special Education Methods Courses in a Preservice Secondary Education Program

    Science.gov (United States)

    Frey, Timothy J.; Andres, Debra K.; McKeeman, Leah A.; Lane, Jessica J.

    2011-01-01

    In this article the authors describe a collaboratively designed secondary teacher education program focused on the preparation of preservice general education teachers to work effectively with children who have diverse learning needs in inclusive classrooms. The focus of the article is on the collaborative development and initial evaluation of the…

  17. Case Studies of Leading Edge Small Urban High Schools. Core Academic Strategic Designs: 1. Academy of the Pacific Rim

    Science.gov (United States)

    Shields, Regis Anne; Ireland, Nicole; City, Elizabeth; Derderian, Julie; Miles, Karen Hawley

    2008-01-01

    This report is one of nine detailed case studies of small urban high schools that served as the foundation for the Education Resource Strategies (ERS) report "Strategic Designs: Lessons from Leading Edge Small Urban High Schools." These nine schools were dubbed "Leading Edge Schools" because they stand apart from other high…

  18. Comparison of Homogeneous and Heterogeneous CFD Fuel Models for Phase I of the IAEA CRP on HTR Uncertainties Benchmark

    Energy Technology Data Exchange (ETDEWEB)

    Gerhard Strydom; Su-Jong Yoon

    2014-04-01

    Computational Fluid Dynamics (CFD) evaluation of homogeneous and heterogeneous fuel models was performed as part of the Phase I calculations of the International Atomic Energy Agency (IAEA) Coordinate Research Program (CRP) on High Temperature Reactor (HTR) Uncertainties in Modeling (UAM). This study was focused on the nominal localized stand-alone fuel thermal response, as defined in Ex. I-3 and I-4 of the HTR UAM. The aim of the stand-alone thermal unit-cell simulation is to isolate the effect of material and boundary input uncertainties on a very simplified problem, before propagation of these uncertainties are performed in subsequent coupled neutronics/thermal fluids phases on the benchmark. In many of the previous studies for high temperature gas cooled reactors, the volume-averaged homogeneous mixture model of a single fuel compact has been applied. In the homogeneous model, the Tristructural Isotropic (TRISO) fuel particles in the fuel compact were not modeled directly and an effective thermal conductivity was employed for the thermo-physical properties of the fuel compact. On the contrary, in the heterogeneous model, the uranium carbide (UCO), inner and outer pyrolytic carbon (IPyC/OPyC) and silicon carbide (SiC) layers of the TRISO fuel particles are explicitly modeled. The fuel compact is modeled as a heterogeneous mixture of TRISO fuel kernels embedded in H-451 matrix graphite. In this study, a steady-state and transient CFD simulations were performed with both homogeneous and heterogeneous models to compare the thermal characteristics. The nominal values of the input parameters are used for this CFD analysis. In a future study, the effects of input uncertainties in the material properties and boundary parameters will be investigated and reported.

  19. Extensive linkage disequilibrium mapping at HTR2A and DRD3 for schizophrenia susceptibility genes in the Galician population.

    Science.gov (United States)

    Domínguez, Eduardo; Loza, María Isabel; Padín, Fernando; Gesteira, Alejandro; Paz, Eduardo; Páramo, Mario; Brenlla, Julio; Pumar, Estefanía; Iglesias, Fernanda; Cibeira, Alcira; Castro, Marián; Caruncho, Héctor; Carracedo, Angel; Costas, Javier

    2007-02-01

    The serotonin and dopamine neurotransmitter systems are candidate pathways in the development of schizophrenia because of the assumed causal relationship with the observed symptoms as well as effective targeting of the corresponding receptors by antipsychotic drugs. However, genetic association studies have systematically focused on a limited set of genes and single nucleotide polymorphisms (SNPs), including T102C at HTR2A and Ser9Gly at DRD3. Meta-analyses of the associations between these two markers and schizophrenia revealed a true increase in risk, the magnitude of the effect being very low. In the present study we analyzed 260 schizophrenic patients and 354 control subjects from a homogeneous population, the Galician population, using an extensive linkage disequilibrium (LD) mapping approach, genotyping a total of 47 SNPs to test for the existence of additional variants that confer higher risk. We detected nominal significant association with schizophrenia for several haplotype tag SNPs (htSNPs) at HTR2A, although the significance was lost after multiple test corrections. In addition, haplotype analyses involving a sliding window approach, with window size 2 to 4 SNPs, revealed significant differences in frequencies of the DRD3 haplotypes at the 3' half of the gene region. This difference, which remains clearly significant after multiple test corrections (p=0.002, 0.0001, and 0.0025, for window sizes 2, 3, and 4, respectively), was mainly due to over-representation of several rare haplotypes in patients, at the expense of a single common haplotype; this represents interesting evidence of rare haplotypes for susceptibility detected using common htSNPs due to their strong effect.

  20. Functionalized porous silica&maghemite core-shell nanoparticles for applications in medicine: design, synthesis, and immunotoxicity

    Science.gov (United States)

    Zasońska, Beata A.; Líšková, Aurélia; Kuricová, Miroslava; Tulinská, Jana; Pop-Georgievski, Ognen; Čiampor, Fedor; Vávra, Ivo; Dušinská, Mária; Ilavská, Silvia; Horváthová, Mira; Horák, Daniel

    2016-01-01

    Aim To determine cytotoxicity and effect of silica-coated magnetic nanoparticles (MNPs) on immune response, in particular lymphocyte proliferative activity, phagocytic activity, and leukocyte respiratory burst and in vitro production of interleukin-6 (IL-6) and 8 (IL-8), interferon-gamma (IFN-γ), tumor necrosis factor-alpha (TNF-α), and granulocyte macrophage colony stimulating factor (GM-CSF). Methods Maghemite was prepared by coprecipitation of iron salts with ammonia, oxidation with NaOCl and modified by tetramethyl orthosilicate and aminosilanes. Particles were characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier-transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS). Cytotoxicity and lymphocyte proliferative activity were assessed using [3H]-thymidine incorporation into DNA of proliferating human peripheral blood cells. Phagocytic activity and leukocyte respiratory burst were measured by flow cytometry; cytokine levels in cell supernatants were determined by ELISA. Results γ-Fe2O3&SiO2-NH2 MNPs were 13 nm in size. According to TEM, they were localized in the cell cytoplasm and extracellular space. Neither cytotoxic effect nor significant differences in T-lymphocyte and T-dependent B-cell proliferative response were found at particle concentrations 0.12-75 μg/cm2 after 24, 48, and 72 h incubation. Significantly increased production of IL-6 and 8, and GM-CSF cytokines was observed in the cells treated with 3, 15, and 75 µg of particles/cm2 for 48 h and stimulated with pokeweed mitogen (PHA). No significant changes in TNF-α and IFN-γ production were observed. MNPs did not affect phagocytic activity of monocytes and granulocytes when added to cells for 24 and 48 h. Phagocytic respiratory burst was significantly enhanced in the cultures exposed to 75 µg MNPs/cm2 for 48 h. Conclusions The cytotoxicity and in vitro immunotoxicity were found to be minimal in the newly developed porous core-shell γ-Fe2

  1. Full MOX core in BWR

    Energy Technology Data Exchange (ETDEWEB)

    Aoyama, Motoo [Power and Industrial Systems R and D Laboratory, Hitachi Ltd., Hitachi, Ibaraki (Japan)

    1999-12-01

    Studies on the core design, the fuel rod thermal-mechanical design and the safety evaluation have been summarized for the Full MOX-ABWR, loaded with MOX fuels up to 100% of the core. Fuel bundle configuration for MOX fuels is identical to the STEP II fuel design and the discharge burnup is about 33 GWd/t. Core performance evaluations and fuel rod thermal-mechanical design analyses have been performed, and it has been confirmed that the design criteria are satisfied with enough margin like the UO{sub 2} fuel loaded core. Safety analyses on transients and accidents have also been performed by considering the MOX fuel and core characteristics adequately through selecting appropriate input data for each safety analysis. All safety criteria are satisfied like the UO{sub 2} core. (author)

  2. Applying core principles to the design and evaluation of the 'Take Charge. Take the Test' campaign: what worked and lessons learned.

    Science.gov (United States)

    Fraze, J L; Uhrig, J D; Davis, K C; Taylor, M K; Lee, N R; Spoeth, S; Robinson, A; Smith, K; Johnston, J; McElroy, L

    2009-09-01

    To describe the application of seven core principles to the design and evaluation of a human immunodeficiency virus (HIV) testing social marketing campaign as a case study example. The Centers for Disease Control and Prevention (CDC) used a structured social marketing approach, informed by the Ecological Model, the Theory of Planned Behaviour and the Health Belief Model, to develop and evaluate a two-city campaign with print, radio and outdoor advertising; HIV telephone hotlines; an HIV website; community partnerships; and events to promote information seeking and HIV testing. The CDC applied seven core principles to design and evaluate the campaign, including formative research, the use of behavioural theories, audience segmentation, message design and pretesting, channel selection, process evaluation and outcome evaluation. Over 200 partners in both cities contributed significantly to campaign efforts. Key informant interviews indicated that, due to increased coordination, city infrastructures for HIV testing improved. More than 9600 individuals attended campaign events in both cities, with 1492 rapid HIV tests administered and 14 newly-identified HIV individuals. Overall, event attendees responded positively to campaign materials and events, and free HIV testing opportunities. The campaign significantly increased information-seeking behaviours in the form of hotline calls and web searches. Audience reaction and receptivity to the final campaign materials was very high. Exposure to campaign messages was associated with increases in key knowledge items, intentions to get tested, and peer-to-peer communication. The seven core principles, including formative research, behavioural theories and extensive partnerships, acted synergistically to help a campaign reach its target audience with compelling, relevant messages and motivate them to seek information and get an HIV test. Rapid testing removes many barriers by providing a testing process that can be accessed and

  3. Full MOX core for ABWR

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Yuki; Yoshioka, Ritsuo; Nagano, Mamoru [Toshiba Corp., Kawasaki, Kanagawa (Japan)

    1996-08-01

    The Japan Atomic Energy Commission has announced the construction plan for an advanced boiling-water reactor (ABWR) with a full MOX (mixed oxide) core instead of ATR. Increased MOX fuel utilization will result in greater savings of uranium ore. A full MOX core for a power plant requires flexibility in MOX fuel utilization, steadiness, and economical operation. We have proposed the optimum full MOX core design for an ABWR based on the MOX fuel and core technologies that we have developed over a period of many years, as well as our considerable experience in uranium fuel and cores. Our full MOX core design for an ABWR has good core characteristics and safety performance with no change in the basic design specifications of the current ABWR. (author)

  4. The Role of 5-HTR6 in Mossy Fiber Sprouting: Activating Fyn and p-ERK1/2 in Pilocarpine-Induced Chronic Epileptic Rats.

    Science.gov (United States)

    Lin, Wanhui; Huang, Wenli; Chen, Shenggen; Lin, Mingxing; Huang, Qingyu; Huang, Huapin

    2017-01-01

    Our primary objective is to verify whether 5-HTR6 is involved in the development of mossy fiber sprouting (MFS), and to determine how the progression of MFS is affected by 5-HTR6. A total of 90 male adult Sprague-Dawley rats were allocated into either the control group (n=36) or the epileptic group (n=54). Status epilepticus (SE) of rats was induced by the intraperitoneal (i.p.) injection of LiCl-pilocarpine. We conducted our experiments in two stages. The first stage involves equally dividing 36 epileptic rats into three groups with treatments of none, 5-HTR6 antagonist SB-27104 (SB) and vehicle DMSO. Then behavior and electroencephalogram (EEG) of rats were monitored by video-EEG. The second stage involves dividing 126 epileptic rats into seven groups with treatments of none, 10% DMSO, SB (100 µg/kg), Fyn antagonist PP2 (50 µg/kg), p-ERK1/2 antagonist PD-98059 (30 µg/kg), SB (100 µg/ kg) + PP2 (50 µg/kg); SB (100 µg/kg) + PD-98059 (30 µg/kg). We also treated 18 rats in the control group of the first stage with 100 µg/kg 5-HTR6 agonist WAY-181187 (WAY). MFS of rats was detected through the approach of Timm's staining. Finally, expressions of 5-HTR6, Fyn, p-ERK1/2 and GAP-3 were qualified and semi-quantified via western blotting or RT-PCR. Induction of SE could stimulate formation of MFS and increased GAP-43 expressions. Expressions of 5-HTR6, Fyn and p-ERK1/2 were also up-regulated with increasing time after establishment of SE models. The development of MFS was remarkably inhibited by SB, PP2 and PD. Compared to the single antagonist, such an inhibitory effect was enhanced by SB+PD or SB+PP. Moreover, treatment of healthy rats with WAY would contribute to up-regulated Fyn and p-ERK1/2 expressions, as well as development of MFS (P MFS by activating both p-ERK1/2 and Fyn, which further modulate the expression of GAP-43. © 2017 The Author(s). Published by S. Karger AG, Basel.

  5. Development of core design and analysis technology for integral reactor; development of coolant activity and dose evaluation program

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Chang Sun; Kim, Byeong Soo; Go, Hyun Seok; Lee, Young Wook; Jang, Mee [Seoul National University, Seoul (Korea)

    2002-03-01

    SMART, small- medium-sized integral reactor, is different from the customary electricity-generation PWR in design concepts and structures. The conventional coolant activity evaluation codes used in customary PWRs cannot be applied to SMART. In this study, SAEP(Specific Activity Evaluation Program) is developed that can be applied to both customary PWR and advanced reactor such as SMART. SAEP uses three methods(SAEP Ver.02, Ver.05, Ver.06) to evaluate coolant activity. They solve inhomogeneous linearly-coupled differential equations generated by considering nuclear system as N sub-components. Coolant activities of customary PWR are evaluated by use of SAEP. The results show good agreement with FSAR data. SAEP is used to evaluate coolant activities for SMART and the results are proposed in this study. These results show that SAEP is able to perform coolant activity evaluation for both customary PWR and advanced reactor such as SMART. In addition, with respect to radiation shielding optimization, conventional optimization methods and their characteristics related to radiation shielding are reviewed and analyzed. Strategies for proper usage of conventional methods are proposed to agree with the shielding design cases. 30 refs., 25 figs., 6 tabs. (Author)

  6. Transformer core

    NARCIS (Netherlands)

    Mehendale, A.; Hagedoorn, Wouter; Lötters, Joost Conrad

    2008-01-01

    A transformer core includes a stack of a plurality of planar core plates of a magnetically permeable material, which plates each consist of a first and a second sub-part that together enclose at least one opening. The sub-parts can be fitted together via contact faces that are located on either side

  7. Transformer core

    NARCIS (Netherlands)

    Mehendale, A.; Hagedoorn, Wouter; Lötters, Joost Conrad

    2010-01-01

    A transformer core includes a stack of a plurality of planar core plates of a magnetically permeable material, which plates each consist of a first and a second sub-part that together enclose at least one opening. The sub-parts can be fitted together via contact faces that are located on either side

  8. Design, synthesis and evaluation of novel triazole core based P-glycoprotein-mediated multidrug resistance reversal agents.

    Science.gov (United States)

    Jiao, Lei; Qiu, Qianqian; Liu, Baomin; Zhao, Tianxiao; Huang, Wenlong; Qian, Hai

    2014-12-15

    A novel series of triazol-N-ethyl-tetrahydroisoquinoline based compounds were designed and synthesized via click chemistry. Most of the synthesized compounds showed P-glycoprotein (P-gp)-mediated multidrug resistance (MDR) reversal activities. Among them, compound 7 with little cytotoxicity towards GES-1 cells (IC50 >80μM) and K562/A02 cells (IC50 >80μM) exhibited more potency than verapamil (VRP) on increasing anticancer drug accumulation in K562/A02 cells. Moreover, compound 7 could significantly reverse MDR in a dose-dependent manner and also persist longer chemo-sensitizing effect than VRP with reversibility. Further mechanism studies revealed that compound 7 in reversing MDR revealed that it could remarkably increase the intracellular accumulation of both rhodamine-123 (Rh123) and adriamycin (ADM) in K562/A02 cells as well as inhibit their efflux from the cells. These results suggested that compound 7 showed more potency than the classical P-gp inhibitor VRP under the same conditions, which may be a promising P-gp-mediated MDR modulator for further development. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Development of core technology for KNGR system design; development of methodology to determine hydrogen ignitor position in KNGR

    Energy Technology Data Exchange (ETDEWEB)

    Park, Goon Chul; Choi, Hee Dong; Whang, Yong Seok; Lee, Un Jang; Lee, Jung Jae; Kim, Do Yeun [Seoul National University, Seoul (Korea)

    2002-04-01

    The scope of this project is to generate fundamental engineering data of hydrogen behavior required in establishing the design guidance and regulation requirement with respect to hydrogen control and severe accident management. This is ultimately to arrange engineering hydrogen control scheme to clear factors threatening integrity of the containment building by hazard of explosion due to burning of hydrogen generated during the severe accident in APR 1400. On the basis of this study, to ensure the safety of nuclear power plant against the severe accident by serving efficient methodology for the positioning of hydrogen igniter is the aim of the project. The project proceeded in 6 phases. Details are followings;1. Capability examination of hydrogen controller. 2. Three dimensional hydrogen mixing experiments and development of He detector. 3. Verification on the three dimensional hydrogen analysis model of the GOTHIC code 4. Development of three dimensional hydrogen mixing code HYCA3D 5. Examination of PAR models 6. Development of methodology to determine hydrogen igniter position. 29 refs., 76 figs., 10 tabs. (Author)

  10. The role of the Cys23Ser (rs6318) polymorphism of the HTR2C gene in suicidal behavior: systematic review and meta-analysis.

    Science.gov (United States)

    González-Castro, Thelma B; Hernandez-Diaz, Yazmín; Juárez-Rojop, Isela E; López-Narváez, Lilia; Tovilla-Zárate, Carlos A; Rodriguez-Perez, José M; Sánchez-de la Cruz, Juan P

    2017-12-01

    The polymorphisms of the serotonin receptor 2C (HTR2C) gene have been proposed to influence suicidal behavior. The aim of our study was to explore the role of the HTR2C gene variant Cys23Ser (rs6318) in the pathogenesis of suicidal behavior through a systematic review and meta-analysis. The search was performed using EBSCO and PubMed databases. To be included in the analysis, the studies had to evaluate suicidal behavior (attempted, ideation, or completed suicide). The results of the meta-analysis were expressed as odds ratios (ORs). Because HTR2C lies on chromosome X, pooled ORs were calculated, respectively, for each of the models used, namely: allelic, homozygous, dominant, and recessive for the female group and allelic for the male group. The meta-analysis comprised 3867 individuals, including 1668 cases and 2199 controls. The HTR2C Cys23Ser (rs6318) polymorphism did not show a significant association with suicidal behavior either in women (OR: 0.75; 95% confidence interval: 0.55-1.00) or in men (OR: 0.89; 95% confidence interval: 0.64-1.23). Similarly, nonsignificant associations were observed for all of the genetic models used in any of the populations/subgroups studied. Our findings suggest that the rs6318 (Cys23Ser) polymorphism is not associated with suicidal behavior. However, because of the study limitations, we suggest more researches should be performed, increasing the sample sizes and statistical power, to determine the association between the rs6318 variant and suicidal behavior.

  11. Rhomboid-7 and HtrA2/Omi act in a common pathway with the Parkinson’s disease factors Pink1 and Parkin

    OpenAIRE

    Whitworth, Alexander J.; Lee, Jeffrey R; Ho, Venus M.-W.; Flick, Robert; Chowdhury, Ruhena; McQuibban, G. Angus

    2008-01-01

    Parkinson’s disease (PD) is a common neurodegenerative disorder caused by loss of midbrain dopaminergic neurons, the pathogenetic mechanisms of which remain unclear. Mitochondrial dysfunction, which has long been implicated in sporadic PD, has recently been highlighted as a key pathological cause, particularly with the identification of mutations in the PTEN-induced putative kinase (pink1), parkin and htrA2 (also known as omi) genes that are linked to PD. Studies in Drosophila melanogaster ha...

  12. Core BPEL

    DEFF Research Database (Denmark)

    Hallwyl, Tim; Højsgaard, Espen

    extensions. Combined with the fact that the language definition does not provide a formal semantics, it is an arduous task to work formally with the language (e.g. to give an implementation). In this paper we identify a core subset of the language, called Core BPEL, which has fewer and simpler constructs......, does not allow omissions, and does not contain ignorable elements. We do so by identifying syntactic sugar, including default values, and ignorable elements in WS-BPEL. The analysis results in a translation from the full language to the core subset. Thus, we reduce the effort needed for working...... formally with WS-BPEL, as one, without loss of generality, need only consider the much simpler Core BPEL. This report may also be viewed as an addendum to the WS-BPEL standard specification, which clarifies the WS-BPEL syntax and presents the essential elements of the language in a more concise way...

  13. Ice Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Records of past temperature, precipitation, atmospheric trace gases, and other aspects of climate and environment derived from ice cores drilled on glaciers and ice...

  14. Core benefits

    National Research Council Canada - National Science Library

    Keith, Brian W

    2010-01-01

    This SPEC Kit explores the core employment benefits of retirement, and life, health, and other insurance -benefits that are typically decided by the parent institution and often have significant governmental regulation...

  15. Hollow Core?

    Science.gov (United States)

    Qiao, G. J.; Liu, J. F.; Wang, Yang; Wu, X. J.; Han, J. L.

    We carried out the Gaussian fitting to the profile of PSR B1237+25 and found that six components rather than five are necessary to make a good fit. In the central part, we found that the core emission is not filled pencil beam but is a small hollow cone. This implies that the impact angle could be $\\beta<0.5^\\circ$. The ``hollow core'' is in agreement with Inverse Compton Scattering model of radio pulsars.

  16. Design of single-winding energy-storage reactors for dc-to-dc converters using air-gapped magnetic-core structures

    Science.gov (United States)

    Ohri, A. K.; Wilson, T. G.; Owen, H. A., Jr.

    1977-01-01

    A procedure is presented for designing air-gapped energy-storage reactors for nine different dc-to-dc converters resulting from combinations of three single-winding power stages for voltage stepup, current stepup and voltage stepup/current stepup and three controllers with control laws that impose constant-frequency, constant transistor on-time and constant transistor off-time operation. The analysis, based on the energy-transfer requirement of the reactor, leads to a simple relationship for the required minimum volume of the air gap. Determination of this minimum air gap volume then permits the selection of either an air gap or a cross-sectional core area. Having picked one parameter, the minimum value of the other immediately leads to selection of the physical magnetic structure. Other analytically derived equations are used to obtain values for the required turns, the inductance, and the maximum rms winding current. The design procedure is applicable to a wide range of magnetic material characteristics and physical configurations for the air-gapped magnetic structure.

  17. MiR-101 regulates apoptosis of trophoblast HTR-8/SVneo cells by targeting endoplasmic reticulum (ER) protein 44 during preeclampsia.

    Science.gov (United States)

    Zou, Y; Jiang, Z; Yu, X; Zhang, Y; Sun, M; Wang, W; Ge, Z; De, W; Sun, L

    2014-10-01

    To investigate a possible association between miR-101 and apoptosis of human trophoblast cells mediated by endoplasmic reticulum protein 44 (ERp44) in preeclampsia (PE), we explored the expression of miR-101 in PE placentas (n=30) compared with normotensive pregnant placentas (n=30) and the correlation between miR-101 and ERp44 was also analyzed. Furthermore, both the apoptotic rate of trophoblast cells and the ER stress-induced apoptotic proteins were assayed when the HTR-8/SVneo cells were treated with miR-101 mimics or inhibitors in vitro. We found a lower expression of miR-101 and an inverse correlation between miR-101 and ERp44 protein in PE placentas. Upregulation of miR-101 expression could inhibit trophoblast HTR-8/SVneo cell apoptosis and repress ER stress-induced apoptotic proteins by targeting ERp44 in vitro, whereas inhibition of miR-101 could induce HTR-8/SVneo cell apoptosis. Our findings indicated that overexpression of miR-101 could downregulate ERp44 and suppress apoptosis in trophoblast cells during PE. Therefore, loss of miR-101 expression could contribute to ER stress-induced trophoblast cell apoptosis by targeting ERp44.

  18. Relationship between the rs1414334 C/G polymorphism in the HTR2C gene and smoking in patients treated with atypical antipsychotics.

    Science.gov (United States)

    Rico-Gomis, José María; Palazón-Bru, Antonio; Triano-García, Irene; Mahecha-García, Luis Fabián; García-Monsalve, Ana; Navarro-Ruiz, Andrés; Villagordo-Peñalver, Berta; Martínez-Hortelano, Alicia; Gil-Guillén, Vicente Francisco

    2017-07-14

    An association has been found between the C allele of the rs1414334 polymorphism in the HTR2C gene and the metabolic syndrome in psychiatric patients. However, no study has yet evaluated whether this allele is associated with smoking. To assess this issue, therefore, we performed a cross-sectional study with a sample of 166 adult patients treated with atypical antipsychotics in 2012-2013 in a region of Spain. The primary variable was the presence of the C allele of the rs1414334 polymorphism in the HTR2C gene. Secondary variables were the number of pack-years (number of cigarettes per day x number of smoking years ÷ 20), age, gender, schizophrenia, years since diagnosis, metabolic syndrome criteria and SCORE. A stepwise binary logistic regression model was constructed to determine associations between primary and secondary variables and their area under the ROC curve (AUC) was calculated. Of the total sample, 33 patients (19.9%) had the C allele of the polymorphism analyzed. Mean cigarette consumption was 11.6 pack-years. The multivariate analysis showed the following factors as associated with the polymorphism: higher cigarette consumption, being a woman, and not having abdominal obesity. The AUC was 0.706. An association was found between increased cigarette consumption over the years and the presence of the C allele of the rs1414334 polymorphism in the HTR2C gene.

  19. Influence of core design, production technique, and material selection on fracture behavior of yttria-stabilized tetragonal zirconia polycrystal fixed dental prostheses produced using different multilayer techniques: split-file, over-pressing, and manually built-up veneers.

    Science.gov (United States)

    Mahmood, Deyar Jallal Hadi; Linderoth, Ewa H; Wennerberg, Ann; Vult Von Steyern, Per

    2016-01-01

    To investigate and compare the fracture strength and fracture mode in eleven groups of currently, the most commonly used multilayer three-unit all-ceramic yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) fixed dental prostheses (FDPs) with respect to the choice of core material, veneering material area, manufacturing technique, design of connectors, and radii of curvature of FDP cores. A total of 110 three-unit Y-TZP FDP cores with one intermediate pontic were made. The FDP cores in groups 1-7 were made with a split-file design, veneered with manually built-up porcelain, computer-aided design-on veneers, and over-pressed veneers. Groups 8-11 consisted of FDPs with a state-of-the-art design, veneered with manually built-up porcelain. All the FDP cores were subjected to simulated aging and finally loaded to fracture. There was a significant difference (Pveneering materials and techniques tested in the study, split-file, over-press, built-up porcelains, and glass-ceramics are, with a great safety margin, sufficient for clinical use both anteriorly and posteriorly. Analysis of the fracture pattern shows differences between the milled veneers and over-pressed or built-up veneers, where the milled ones show numerically more veneer cracks and the other groups only show complete connector fractures.

  20. Influence of core design, production technique, and material selection on fracture behavior of yttria-stabilized tetragonal zirconia polycrystal fixed dental prostheses produced using different multilayer techniques: split-file, over-pressing, and manually built-up veneers

    Science.gov (United States)

    Mahmood, Deyar Jallal Hadi; Linderoth, Ewa H; Wennerberg, Ann; Vult Von Steyern, Per

    2016-01-01

    Aim To investigate and compare the fracture strength and fracture mode in eleven groups of currently, the most commonly used multilayer three-unit all-ceramic yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) fixed dental prostheses (FDPs) with respect to the choice of core material, veneering material area, manufacturing technique, design of connectors, and radii of curvature of FDP cores. Materials and methods A total of 110 three-unit Y-TZP FDP cores with one intermediate pontic were made. The FDP cores in groups 1–7 were made with a split-file design, veneered with manually built-up porcelain, computer-aided design-on veneers, and over-pressed veneers. Groups 8–11 consisted of FDPs with a state-of-the-art design, veneered with manually built-up porcelain. All the FDP cores were subjected to simulated aging and finally loaded to fracture. Results There was a significant difference (Pveneering materials and techniques tested in the study, split-file, over-press, built-up porcelains, and glass–ceramics are, with a great safety margin, sufficient for clinical use both anteriorly and posteriorly. Analysis of the fracture pattern shows differences between the milled veneers and over-pressed or built-up veneers, where the milled ones show numerically more veneer cracks and the other groups only show complete connector fractures. PMID:26929667

  1. Birefringent hollow core fibers

    DEFF Research Database (Denmark)

    Roberts, John

    2007-01-01

    Hollow core photonic crystal fiber (HC-PCF), fabricated according to a nominally non-birefringent design, shows a degree of un-controlled birefringence or polarization mode dispersion far in excess of conventional non polarization maintaining fibers. This can degrade the output pulse in many...... and an increased overlap between the polarization modes at the glass interfaces. The interplay between these effects leads to a wavelength for optimum polarization maintenance, lambda(PM), which is detuned from the wavelength of highest birefringence. By a suitable fiber design involving antiresonance of the core...

  2. Validation of a Computational Model for the SLS Core Stage Oxygen Tank Diffuser Concept and the Low Profile Diffuser - An Advanced Development Design for the SLS

    Science.gov (United States)

    Brodnick, Jacob; Richardson, Brian; Ramachandran, Narayanan

    2015-01-01

    The Low Profile Diffuser (LPD) project originated as an award from the Marshall Space Flight Center (MSFC) Advanced Development (ADO) office to the Main Propulsion Systems Branch (ER22). The task was created to develop and test an LPD concept that could produce comparable performance to a larger, traditionally designed, ullage gas diffuser while occupying a smaller volume envelope. Historically, ullage gas diffusers have been large, bulky devices that occupy a significant portion of the propellant tank, decreasing the tank volume available for propellant. Ullage pressurization of spacecraft propellant tanks is required to prevent boil-off of cryogenic propellants and to provide a positive pressure for propellant extraction. To achieve this, ullage gas diffusers must slow hot, high-pressure gas entering a propellant tank from supersonic speeds to only a few meters per second. Decreasing the incoming gas velocity is typically accomplished through expansion to larger areas within the diffuser which has traditionally led to large diffuser lengths. The Fluid Dynamics Branch (ER42) developed and applied advanced Computational Fluid Dynamics (CFD) analysis methods in order to mature the LPD design from and initial concept to an optimized test prototype and to provide extremely accurate pre-test predictions of diffuser performance. Additionally, the diffuser concept for the Core Stage of the Space Launch System (SLS) was analyzed in a short amount of time to guide test data collection efforts of the qualification of the device. CFD analysis of the SLS diffuser design provided new insights into the functioning of the device and was qualitatively validated against hot wire anemometry of the exterior flow field. Rigorous data analysis of the measurements was performed on static and dynamic pressure data, data from two microphones, accelerometers and hot wire anemometry with automated traverse. Feasibility of the LPD concept and validation of the computational model were

  3. Wire core reactor for NTP

    Science.gov (United States)

    Harty, R. B.

    1991-01-01

    The development of the wire core system for Nuclear Thermal Propulsion (NTP) that took place from 1963 to 1965 is discussed. A wire core consists of a fuel wire with spacer wires. It's an annular flow core having a central control rod. There are actually four of these, with beryllium solid reflectors on both ends and all the way around. Much of the information on the concept is given in viewgraph form. Viewgraphs are presented on design details of the wire core, the engine design, engine weight vs. thrust, a technique used to fabricate the wire fuel element, and axial temperature distribution.

  4. Design of low DMD few-mode optical fibers with extremely enlarged core diameter providing nonlinearity suppression for operating over "C"-band central region

    Science.gov (United States)

    Andreev, Vladimir A.; Bourdine, Anton V.; Burdin, Vladimir A.; Evtushenko, Alexander S.; Halikov, Rashid H.

    2017-04-01

    We present method for design of refractive index profile for silica GeO2-doped graded-index few-mode optical fibers with reduced differential mode delay and suppressed mode nonlinearity due to extremely enlarged core diameter up to 42 μm. Proposed solution is based on earlier on developed modified Gaussian approximation generalized for analysis of silica weakly guiding optical fibers with single outer cladding and arbitrary axially-symmetric refractive index profile, that provides ability to derive analytical expressions for guided mode delays. Therefore the objective function is represented as a sum of squares of deviations between mode staff delays and reference value corresponding to refractive index profile of current iteration. Based on developed method we performed computation for various combination of the reference mode delay and first iteration profile parameter. Some results of desired graded-index profile for a few-mode optical fibers 42/125 providing differential mode delay minimization over central region of "C"-band are represented.

  5. Core Obstetrics and Gynaecology*

    African Journals Online (AJOL)

    Core Obstetrics and Gynaecology*. By J. T. Nel. Pp xvii + 992. Illustrated. Durban: Butterworths. 1995. ISBN 0-409-10134-6. For some years now, I have lamented the absence of a good, home-grown, comprehensive, student-centred textbook of obstetrics and gynaecology designed specifically for South African needs.

  6. STUDI DESAIN DOWN SCALE TERAS REAKTOR DAN BAHAN BAKAR PLTN JENIS PEBBLE BED MODULAR REACTOR – HTR 100 MWe

    Directory of Open Access Journals (Sweden)

    Slamet Parmanto

    2015-04-01

    Full Text Available Telah dilakukan penelitian terhadap teras reaktor Pebble Bed Modular Reactor (PBMR dengan daya 100 Mwe berbahan bakar UO2. Reaktor ini menggunakan moderator grafit dan helium sebagai pendingin. Studi down scale dilakukan tanpa mengubah geometri teras maupun geometri bahan bakar. Parameter yang dianalisis adalah kritikalitas teras, reaktivitas lebih, koefisien reaktivitas temperatur bahan bakar, moderator dan pendingin serta nilai ekonomis bahan bakar. Dari penelitian ini diharapkan diperoleh desain bahan bakar yang bernilai ekonomis dan memiliki fitur keselamatan melekat. Penelitian dilakukan dengan menggunakan program SRAC 2003. Hasil yang diperoleh adalah desain bahan bakar UO2 berbentuk pebble dengan pengkayaan 10% U235 dan 90 ppm racun dapat bakar Gd2O3. Nilai faktor multipilkasi effektif keff pada beginning of life (BOL adalah 1,01115 dan menjadi 1,00588 setelah 2658 hari operasi reaktor (EOL. Koefisien reaktivitas temperatur total diperoleh sebesar - 3,25900E-05 ∆k/k/K saat BOL dan -1,10615E-04 ∆k/k/K saat end of life (EOL. Reaktor ini memenuhi karakteristik keselamatan melekat ditandai dengan nilai koefisien reaktivitas temperatur yang negatif. Kata kunci: PBMR, desain bahan bakar, faktor multipilkasi effektif, reaktivitas lebih, koefisien reaktivitas temperatur.   Research of Pebble Bed Modular Reactor (PBMR 100 MWe which used UO2 fuel has been done. This reactor uses graphite as moderator and helium as coolant. Down scale studies performed without changing the core and fuel geometry. The parameter being analyzed were core criticality, excess reactivity, fuel, moderator, coolant temperature reactivity coefficient, and fuel economy. This research is expected to obtain the design that has fuel economy and inherent safety features. In this research, we have employed SRAC 2003 code. The calculation show that the UO2 pebble fuel design with 10% enrichment of U235 and 90 ppm burnable poison of Gd2O3 results in the effective multiplication

  7. MCNP LWR Core Generator

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Noah A. [Los Alamos National Laboratory

    2012-08-14

    The reactor core input generator allows for MCNP input files to be tailored to design specifications and generated in seconds. Full reactor models can now easily be created by specifying a small set of parameters and generating an MCNP input for a full reactor core. Axial zoning of the core will allow for density variation in the fuel and moderator, with pin-by-pin fidelity, so that BWR cores can more accurately be modeled. LWR core work in progress: (1) Reflectivity option for specifying 1/4, 1/2, or full core simulation; (2) Axial zoning for moderator densities that vary with height; (3) Generating multiple types of assemblies for different fuel enrichments; and (4) Parameters for specifying BWR box walls. Fuel pin work in progress: (1) Radial and azimuthal zoning for generating further unique materials in fuel rods; (2) Options for specifying different types of fuel for MOX or multiple burn assemblies; (3) Additional options for replacing fuel rods with burnable poison rods; and (4) Control rod/blade modeling.

  8. Influence of core design, production technique, and material selection on fracture behavior of yttria-stabilized tetragonal zirconia polycrystal fixed dental prostheses produced using different multilayer techniques: split-file, over-pressing, and manually built-up veneers

    Directory of Open Access Journals (Sweden)

    Mahmood DJH

    2016-02-01

    Full Text Available Deyar Jallal Hadi Mahmood, Ewa H Linderoth, Ann Wennerberg, Per Vult Von Steyern Department of Prosthetic Dentistry, Faculty of Odontology, Malmö University, Malmö, Sweden Aim: To investigate and compare the fracture strength and fracture mode in eleven groups of currently, the most commonly used multilayer three-unit all-ceramic yttria-stabilized tetragonal zirconia polycrystal (Y-TZP fixed dental prostheses (FDPs with respect to the choice of core material, veneering material area, manufacturing technique, design of connectors, and radii of curvature of FDP cores. Materials and methods: A total of 110 three-unit Y-TZP FDP cores with one intermediate pontic were made. The FDP cores in groups 1–7 were made with a split-file design, veneered with manually built-up porcelain, computer-aided design-on veneers, and over-pressed veneers. Groups 8–11 consisted of FDPs with a state-of-the-art design, veneered with manually built-up porcelain. All the FDP cores were subjected to simulated aging and finally loaded to fracture. Results: There was a significant difference (P<0.05 between the core designs, but not between the different types of Y-TZP materials. The split-file designs with VITABLOCS® (1,806±165 N and e.max® ZirPress (1,854±115 N and the state-of-the-art design with VITA VM® 9 (1,849±150 N demonstrated the highest mean fracture values. Conclusion: The shape of a split-file designed all-ceramic reconstruction calls for a different dimension protocol, compared to traditionally shaped ones, as the split-file design leads to sharp approximal indentations acting as fractural impressions, thus decreasing the overall strength. The design of a framework is a crucial factor for the load bearing capacity of an all-ceramic FDP. The state-of-the-art design is preferable since the split-file designed cores call for a cross-sectional connector area at least 42% larger, to have the same load bearing capacity as the state-of-the-art designed

  9. Place-based research project design for 10-week REU and two-week "mini-REU" internships using lake sediment cores

    Science.gov (United States)

    Myrbo, A.; Howes, T.; Thompson, R.; Drake, C.; Woods, P.; Schuldt, N.; Borkholder, B.; Marty, J.; Lafrancois, T.; Pellerin, H.

    2012-12-01

    Lake sediment cores provide scalable, interdisciplinary research projects that are well suited for summer internships such as the NSF-REU (Research Experience for Undergraduates). Short paleorecords (100-500 years or about a meter of core) are easy to collect and are tractable in terms of sample numbers (Myrbo et al. 2011). Many students find it compelling to reconstruct the recent past; choosing sites with cultural or historical significance is another way to make research seem more relevant. We present the results and experiences of designing two- and ten-week individual, group, and team research projects. Each of these projects contributes to the findings of a collaborative inquiry by the Fond du Lac Band of Lake Superior Chippewa (FDL) and the University of Minnesota (UMN). Research questions are determined and framed by FDL Resource Management, and student projects are supported and advised by both FDL and UMN scientists. The research is focused on the past environmental conditions of on- and off-Reservation wild rice lakes and the surrounding landscapes and people, and includes the study of biological and chemical proxies as well as historical records. Over the past three years, this approach has enabled diverse groups of students to conduct authentic and original basic research that also has applications to management and planning issues for Tribal resource managers, and to develop skills that are portable to other management and academic settings. These compelling "short" time scale projects can serve as a gateway for students to further pursue science including longer term paleorecords, climate change research, other disciplines in ecology, water resources, geography, archeology, and geology, as well as humanities research areas such as history and landscape architecture. An overarching goal is to help students understand current environmental change in the context of long-term changes, pre-industrial human land use, and accelerated Anthropocene impacts

  10. Dynamic behavior of the HTR-10 reactor: Dual temperature feedback model

    Directory of Open Access Journals (Sweden)

    Hosseini Seyed Ali

    2015-01-01

    Full Text Available The current work aims at presenting a simple model for PBM-type reactors' dynamic behavior analysis. The proposed model is based on point kinetics equations coupled with feedbacks from fuel and moderator temperatures. The temperature reactivity coefficients were obtained through MCNP code and via available experimental data. Parameters such as heat capacity and heat conductivity were carefully analyzed and the final system of equations was numerically solved. The obtained results, while in partial agreement with previously proposed models, suggest lower sensitivity to step reactivity insertion as compared to other reactor designs and inherent safety of the design.

  11. Hydrocarbon Degradation in Caspian Sea Sediment Cores Subjected to Simulated Petroleum Seepage in a Newly Designed Sediment-Oil-Flow-Through System

    Directory of Open Access Journals (Sweden)

    Tina Treude

    2017-04-01

    Full Text Available The microbial community response to petroleum seepage was investigated in a whole round sediment core (16 cm length collected nearby natural hydrocarbon seepage structures in the Caspian Sea, using a newly developed Sediment-Oil-Flow-Through (SOFT system. Distinct redox zones established and migrated vertically in the core during the 190 days-long simulated petroleum seepage. Methanogenic petroleum degradation was indicated by an increase in methane concentration from 8 μM in an untreated core compared to 2300 μM in the lower sulfate-free zone of the SOFT core at the end of the experiment, accompanied by a respective decrease in the δ13C signal of methane from -33.7 to -49.5‰. The involvement of methanogens in petroleum degradation was further confirmed by methane production in enrichment cultures from SOFT sediment after the addition of hexadecane, methylnapthalene, toluene, and ethylbenzene. Petroleum degradation coupled to sulfate reduction was indicated by the increase of integrated sulfate reduction rates from 2.8 SO42-m-2 day-1 in untreated cores to 5.7 mmol SO42-m-2 day-1 in the SOFT core at the end of the experiment, accompanied by a respective accumulation of sulfide from 30 to 447 μM. Volatile hydrocarbons (C2–C6 n-alkanes passed through the methanogenic zone mostly unchanged and were depleted within the sulfate-reducing zone. The amount of heavier n-alkanes (C10–C38 decreased step-wise toward the top of the sediment core and a preferential degradation of shorter (C30 was seen during the seepage. This study illustrates, to the best of our knowledge, for the first time the development of methanogenic petroleum degradation and the succession of benthic microbial processes during petroleum passage in a whole round sediment core.

  12. Upregulation of long noncoding RNA SPRY4-IT1 modulates proliferation, migration, apoptosis, and network formation in trophoblast cells HTR-8SV/neo.

    Directory of Open Access Journals (Sweden)

    Yanfen Zou

    Full Text Available SPRY4-IT1 has been reported to have extremely high expression in normal placenta tissues. It is a Long noncoding RNA (lncRNA, which is associated with cell growth, migration, invasion, and apoptosis in melanoma. A 2.8-fold increase of SPRY4-IT1 expression was validated by Real-time reverse transcription-polymerase chain reaction (qRT-PCR in severe preeclamptic placenta as compared with that of the normal ones (n=25 in this study. Furthermore, the role of SPRY4-IT1 in proliferation, migration, apoptosis, and network formation ability of trophoblast cells HTR-8/SVneo was assessed. Suppression of SPRY4-IT1 using siRNA treatment and its overexpression using plasmid targeting SPRY4-IT1 were performed in order to explore the biological function of SPRY4-IT1 in the development and progression of trophoblast cells HTR-8/SVneo, in vitro. The results showed that SPRY4-IT1 knockdown enhanced the cell migration and proliferation, and reduced the response of cells to apoptosis. However, exogenous SPRY4-IT1 overexpression significantly decreased the cell migration and proliferation, while increased cell apoptosis. Our study showed for the first time that aberrant expression of lncRNA SPRY4-IT1 might contribute to the abnormal condition of trophoblast cells HTR-8/SVneo. Therefore, we proposed SPRY4-IT1 as a novel lncRNA molecule, which might be associated with the pathogenesis of preeclampsia and might provide a new target for its early diagnosis and treatment.

  13. Serotonin 2A receptor gene (HTR2A) regulatory variants: possible association with severity of depression symptoms in children with autism spectrum disorder.

    Science.gov (United States)

    Gadow, Kenneth D; Smith, Ryan M; Pinsonneault, Julia K

    2014-06-01

    Our aim was to characterize the association of 2 functional single nucleotide polymorphisms (rs6311 and rs6314) in the serotonin 2A receptor gene (HTR2A) with severity of depression symptoms in children with autism spectrum disorder. These polymorphisms have been shown to be associated with depression symptom severity and response to selective serotonin reuptake inhibitor drugs in adults with diagnosed depressive disorder. Parents of 104 children with autism spectrum disorder rated their children's depressive symptoms using a validated scale based on criteria from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. We compared severity of depression symptoms across the rs6311 and rs6314 genotypes, measured from the children's genomic DNA. Children homozygous for the G allele of rs6311 had significantly more severe depression symptoms than those with G/A or A/A genotypes (P=0.025). The effect size (partial eta-squared) was small (ηp=0.047) but was somewhat larger when we controlled for severity of generalized anxiety disorder symptoms (P=0.006, ηp=0.072). When we restricted our analyses to white participants, our results were essentially the same as for the entire sample (P=0.004, ηp=0.086). There was no significant association between rs6314 (C/C versus T carriers) and severity of depression. Our findings suggest that the HTR2A functional rs6311 polymorphism, which other studies have associated with differential HTR2A mRNA expression, may modulate the severity of depression symptoms in children with autism spectrum disorder. These tentative, hypothesis-generating findings need replication with larger, independent samples.

  14. Moderate mammalian target of rapamycin inhibition induces autophagy in HTR8/SVneo cells via O-linked β-N-acetylglucosamine signaling.

    Science.gov (United States)

    Zhang, Qiuxia; Na, Quan; Song, Weiwei

    2017-10-01

    Autophagy, a highly regulated process with a dual role (pro-survival or pro-death), has been implicated in adverse pregnancy outcomes. The aim of this study was to explore the mechanism whereby mammalian target of rapamycin (mTOR) signaling regulates autophagy by modulating protein O-GlcNAcylation in human trophoblasts. HTR8/SVneo cells were incubated in serum-free medium for different time intervals or treated with varying doses of Torin1. Protein expression and cell apoptosis were detected by immunoblotting and flow cytometry, respectively. Short-term serum starvation or slight suppression of mTOR signaling promoted autophagy and decreased apoptosis in HTR8/SVneo cells. Conversely, prolonged serum starvation or excessive inhibition of mTOR reduced autophagy and enhanced cell apoptosis. Both serum starvation and mTOR signaling suppression reduced protein O-GlcNAcylation. Upregulation and downregulation of O-linked β-N-acetylglucosamine (O-GlcNAc) levels attenuated and augmented autophagy, respectively. Moderate mTOR inhibition-induced autophagy was blocked by upregulation of protein O-GlcNAcylation. Furthermore, immunoprecipitation studies revealed that Beclin1 and synaptosome associated protein 29 (SNAP29) could be O-GlcNAcylated, and that slight mTOR inhibition resulted in decreased O-GlcNAc modification of Beclin1 and SNAP29. Notably, we observed an inverse correlation between phosphorylation (Ser15) and O-GlcNAcylation of Beclin1. mTOR signaling inhibition played dual roles in regulating autophagy and apoptosis in HTR8/SVneo cells. Moderate mTOR suppression might induce autophagy via modulating O-GlcNAcylation of Beclin1 and SNAP29. Moreover, the negative interplay between Beclin1 O-GlcNAcylation and phosphorylation (Ser15) may be involved in autophagy regulation by mTOR signaling. © 2017 Japan Society of Obstetrics and Gynecology.

  15. Packing in protein cores

    Science.gov (United States)

    Gaines, J. C.; Clark, A. H.; Regan, L.; O'Hern, C. S.

    2017-07-01

    Proteins are biological polymers that underlie all cellular functions. The first high-resolution protein structures were determined by x-ray crystallography in the 1960s. Since then, there has been continued interest in understanding and predicting protein structure and stability. It is well-established that a large contribution to protein stability originates from the sequestration from solvent of hydrophobic residues in the protein core. How are such hydrophobic residues arranged in the core; how can one best model the packing of these residues, and are residues loosely packed with multiple allowed side chain conformations or densely packed with a single allowed side chain conformation? Here we show that to properly model the packing of residues in protein cores it is essential that amino acids are represented by appropriately calibrated atom sizes, and that hydrogen atoms are explicitly included. We show that protein cores possess a packing fraction of φ ≈ 0.56 , which is significantly less than the typically quoted value of 0.74 obtained using the extended atom representation. We also compare the results for the packing of amino acids in protein cores to results obtained for jammed packings from discrete element simulations of spheres, elongated particles, and composite particles with bumpy surfaces. We show that amino acids in protein cores pack as densely as disordered jammed packings of particles with similar values for the aspect ratio and bumpiness as found for amino acids. Knowing the structural properties of protein cores is of both fundamental and practical importance. Practically, it enables the assessment of changes in the structure and stability of proteins arising from amino acid mutations (such as those identified as a result of the massive human genome sequencing efforts) and the design of new folded, stable proteins and protein-protein interactions with tunable specificity and affinity.

  16. Polymorphism in the serotonin receptor 2a (HTR2A) gene as possible predisposal factor for aggressive traits.

    Science.gov (United States)

    Banlaki, Zsofia; Elek, Zsuzsanna; Nanasi, Tibor; Szekely, Anna; Nemoda, Zsofia; Sasvari-Szekely, Maria; Ronai, Zsolt

    2015-01-01

    Aggressive manifestations and their consequences are a major issue of mankind, highlighting the need for understanding the contributory factors. Still, aggression-related genetic analyses have so far mainly been conducted on small population subsets such as individuals suffering from a certain psychiatric disorder or a narrow-range age cohort, but no data on the general population is yet available. In the present study, our aim was to identify polymorphisms in genes affecting neurobiological processes that might explain some of the inter-individual variation between aggression levels in the non-clinical Caucasian adult population. 55 single nucleotide polymorphisms (SNP) were simultaneously determined in 887 subjects who also filled out the self-report Buss-Perry Aggression Questionnaire (BPAQ). Single marker association analyses between genotypes and aggression scores indicated a significant role of rs7322347 located in the HTR2A gene encoding serotonin receptor 2a following Bonferroni correction for multiple testing (p = 0.0007) both for males and females. Taking the four BPAQ subscales individually, scores for Hostility, Anger and Physical Aggression showed significant association with rs7322347 T allele in themselves, while no association was found with Verbal Aggression. Of the subscales, relationship with rs7322347 was strongest in the case of Hostility, where statistical significance virtually equaled that observed with the whole BPAQ. In conclusion, this is the first study to our knowledge analyzing SNPs in a wide variety of genes in terms of aggression in a large sample-size non-clinical adult population, also describing a novel candidate polymorphism as predisposal to aggressive traits.

  17. Polymorphism in the serotonin receptor 2a (HTR2A gene as possible predisposal factor for aggressive traits.

    Directory of Open Access Journals (Sweden)

    Zsofia Banlaki

    Full Text Available Aggressive manifestations and their consequences are a major issue of mankind, highlighting the need for understanding the contributory factors. Still, aggression-related genetic analyses have so far mainly been conducted on small population subsets such as individuals suffering from a certain psychiatric disorder or a narrow-range age cohort, but no data on the general population is yet available. In the present study, our aim was to identify polymorphisms in genes affecting neurobiological processes that might explain some of the inter-individual variation between aggression levels in the non-clinical Caucasian adult population. 55 single nucleotide polymorphisms (SNP were simultaneously determined in 887 subjects who also filled out the self-report Buss-Perry Aggression Questionnaire (BPAQ. Single marker association analyses between genotypes and aggression scores indicated a significant role of rs7322347 located in the HTR2A gene encoding serotonin receptor 2a following Bonferroni correction for multiple testing (p = 0.0007 both for males and females. Taking the four BPAQ subscales individually, scores for Hostility, Anger and Physical Aggression showed significant association with rs7322347 T allele in themselves, while no association was found with Verbal Aggression. Of the subscales, relationship with rs7322347 was strongest in the case of Hostility, where statistical significance virtually equaled that observed with the whole BPAQ. In conclusion, this is the first study to our knowledge analyzing SNPs in a wide variety of genes in terms of aggression in a large sample-size non-clinical adult population, also describing a novel candidate polymorphism as predisposal to aggressive traits.

  18. HTR-Based Power Plants’ Performance Analysis Applied on Conventional Combined Cycles

    OpenAIRE

    José Carbia Carril; Álvaro Baaliña Insua; Javier Romero Gómez; Manuel Romero Gómez

    2015-01-01

    In high temperature reactors including gas cooled fast reactors and gas turbine modular helium reactors (GT-MHR) specifically designed to operate as power plant heat sources, efficiency enhancement at effective cost under safe conditions can be achieved. Mentioned improvements concern the implementation of two cycle structures: (a), a stand alone Brayton operating with helium and a stand alone Rankine cycle (RC) with regeneration, operating with carbon dioxide at ultrasupercritical pressure a...

  19. Development of an integrated fission product release and transport code for spatially resolved full-core calculations of V/HTRs

    Energy Technology Data Exchange (ETDEWEB)

    Xhonneux, Andre, E-mail: a.xhonneux@fz-juelich.de [Forschungszentrum Jülich, 52425 Jülich (Germany); Institute for Reactor Safety and Reactor Technology RWTH-Aachen, 52064 Aachen (Germany); Allelein, Hans-Josef [Forschungszentrum Jülich, 52425 Jülich (Germany); Institute for Reactor Safety and Reactor Technology RWTH-Aachen, 52064 Aachen (Germany)

    2014-05-01

    The computer codes FRESCO-I, FRESCO-II, PANAMA and SPATRA developed at Forschungszentrum Jülich in Germany in the early 1980s are essential tools to predict the fission product release from spherical fuel elements and the TRISO fuel performance, respectively, under given normal or accidental conditions. These codes are able to calculate a conservative estimation of the source term, i.e. quantity and duration of radionuclide release. Recently, these codes have been reversed engineered, modernized (FORTRAN 95/2003) and combined to form a consistent code named STACY (Source Term Analysis Code System). STACY will later become a module of the V/HTR Code Package (HCP). In addition, further improvements have been implemented to enable more detailed calculations. For example the distinct temperature profile along the pebble radius is now taken into account and coated particle failure rates can be calculated under normal operating conditions. In addition, the absolute fission product release of an V/HTR pebble bed core can be calculated by using the newly developed burnup code Topological Nuclide Transformation (TNT) replacing the former rudimentary approach. As a new functionality, spatially resolved fission product release calculations for normal operating conditions as well as accident conditions can be performed. In case of a full-core calculation, a large number of individual pebbles which follow a random path through the reactor core can be simulated. The history of the individual pebble is recorded, too. Main input data such as spatially resolved neutron fluxes and fluid dynamics data are provided by the VSOP code. Capabilities of the FRESCO-I and SPATRA code which allow for the simulation of the redistribution of fission products within the primary circuit and the deposition of fission products on graphitic and metallic surfaces are also available in STACY. In this paper, details of the STACY model and first results for its application to the 200 MW(th) HTR

  20. Saturation current spikes eliminated in saturable core transformers

    Science.gov (United States)

    Schwarz, F. C.

    1971-01-01

    Unsaturating composite magnetic core transformer, consisting of two separate parallel cores designed so impending core saturation causes signal generation, terminates high current spike in converter primary circuit. Simplified waveform, demonstrates transformer effectiveness in eliminating current spikes.

  1. Designing of luminescent GdPO4:Eu@LaPO4@SiO2 core/shell nanorods: Synthesis, structural and luminescence properties

    Science.gov (United States)

    Ansari, Anees A.; Labis, Joselito P.; Aslam Manthrammel, M.

    2017-09-01

    GdPO4:Eu3+ (core) and GdPO4:Eu@LaPO4 (core/shell) nanorods (NRs) were successfully prepared by urea based co-precipitation process at ambient conditions which was followed by coating with amorphous silica shell via the sol-gel chemical route. The role of surface coating on the crystal structure, crystallinity, morphology, solubility, surface chemistry and luminescence properties were well investigated by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive X-ray (EDX) analysis, Fourier Transform Infrared (FTIR), UV-Vis, and photoluminescence spectroscopy. XRD pattern revealed highly purified, well-crystalline, single phase-hexagonal-rhabdophane structure of GdPO4 crystal. The TEM micrographs exhibited highly crystalline and narrow size distributed rod-shaped GdPO4:Eu3+ nanostructures with average width 14-16 nm and typical length 190-220 nm. FTIR spectra revealed characteristic infrared absorption bands of amorphous silica. High absorbance in a visible region of silica modified core/shell/Si NRs in aqueous environment suggests the high solubility along with colloidal stability. The photoluminescence properties were remarkably enhanced after growth of undoped LaPO4 layers due to the reduction of nonradiative transition rate. The advantages of presented high emission intensity and high solubility of core/shell and core/shell/Si NRs indicated the potential applications in monitoring biological events.

  2. Blocking Epidermal Growth Factor Receptor Signaling in HTR-8/SVneo First Trimester Trophoblast Cells Results in Dephosphorylation of PKBα/AKT and Induces Apoptosis

    Directory of Open Access Journals (Sweden)

    J. Bolnick

    2011-01-01

    Full Text Available We identified a major peptide signaling target of EGF/EGFR pathway and explored the consequences of blocking or activating this pathway in the first trimester extravillous trophoblast cells, HTR-8/SVneo. A global analysis of protein phosphorylation was undertaken using novel technology (Kinexus Kinetworks that utilizes SDS-polyacrylamide minigel electrophoresis and multi-lane immunoblotting to permit specific and semiquantitative detection of multiple phosphoproteins. Forty-seven protein phosphorylation sites were queried, and the results reported based on relative phosphorylation at each site. EGF- and Iressa-(gefitinib, ZD1839, an inhibitor of EGFR treated HTR-8/SVneo cells were subjected to immunoblotting and flow cytometry to confirm the phosphoprotein screen and to assess the effects of EGF versus Iressa on cell cycle and apoptosis. EGFR mediates the phosphorylation of important signaling proteins, including PKBα/AKT. This pathway is likely to be central to EGFR-mediated trophoblast survival. Furthermore, EGF treatment induces proliferation and inhibits apoptosis, while Iressa induces apoptosis.

  3. Association between HTR2C gene variants and suicidal behaviour: a protocol for the systematic review and meta-analysis of genetic studies.

    Science.gov (United States)

    Thelma Beatriz, González-Castro; Isela, Juárez-Rojop; Alma, Genis; María Lilia, López-Narváez; Carlos Alfonso, Tovilla-Zárate

    2014-09-04

    Suicide is an important public health problem and one of the most common causes of death throughout the world. Suicidal behaviour is complex, and its causes are multifactorial. Case-control studies have reported an association between an alteration of the serotonin system and suicidal behaviour. Recently, it has been suggested that the 5-HTRC2 serotonin receptor gene is involved in the pathogenesis of suicidal behaviour. To evaluate the role of the 5-HTR2C gene in suicidal behaviour, we will perform a systematic review and a meta-analysis of worldwide reports that have investigated the association between the serotonin system and suicidal behaviour. This analysis will be reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Studies deemed fit for inclusion in the systematic review will be scored for methodological quality using the Newcastle-Ottawa Assessment Scale (NOS). The inclusion criteria will be to present independent data, to be case-control studies and to be published in journal peer reviews. To generate more accurate analyses, we will grade the reports using the GRADES scale procedures. This study will describe the association between the HTR2C gene and suicidal behaviour. The results will be reported in a peer-reviewed publication and in scientific presentations in Mexico and throughout the world. PROSPERO CRD42014009213. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  4. Role of GAD2 and HTR1B genes in early-onset obsessive-compulsive disorder: results from transmission disequilibrium study.

    Science.gov (United States)

    Mas, S; Pagerols, M; Gassó, P; Ortiz, A; Rodriguez, N; Morer, A; Plana, M T; Lafuente, A; Lazaro, L

    2014-04-01

    One of the leading biological models of obsessive-compulsive disorder (OCD) is the frontal-striatal-thalamic model. This study undertakes an extensive exploration of the variability in genes related to the regulation of the frontal-striatal-thalamic system in a sample of early-onset OCD trios. To this end, we genotyped 266 single nucleotide polymorphisms (SNPs) in 35 genes in 84 OCD probands and their parents. Finally, 75 complete trios were included in the analysis. Twenty SNPs were overtransmitted from parents to early-onset OCD probands and presented nominal pointwise P gender, different trends were observed between males and females. In males, SNP rs2000292 (HTR1B) showed the lowest P-value (P = 0.0006), whereas the SNPs in GAD2 were only marginally significant (P = 0.01). In contrast, in females HTR1B polymorphisms were not significant, whereas rs8190748 (GAD2) showed the lowest P-value (P = 0.0006). These results are in agreement with several lines of evidence that indicate a role for the serotonin and γ-Aminobutyric acid (GABA) pathways in the risk of early-onset OCD and with the gender differences in OCD pathophysiology reported elsewhere. However, our results need to be replicated in studies with larger cohorts in order to confirm these associations. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  5. HTR-Based Power Plants’ Performance Analysis Applied on Conventional Combined Cycles

    Directory of Open Access Journals (Sweden)

    José Carbia Carril

    2015-01-01

    Full Text Available In high temperature reactors including gas cooled fast reactors and gas turbine modular helium reactors (GT-MHR specifically designed to operate as power plant heat sources, efficiency enhancement at effective cost under safe conditions can be achieved. Mentioned improvements concern the implementation of two cycle structures: (a, a stand alone Brayton operating with helium and a stand alone Rankine cycle (RC with regeneration, operating with carbon dioxide at ultrasupercritical pressure as working fluid (WF, where condensation is carried out at quasicritical conditions, and (b, a combined cycle (CC, in which the topping closed Brayton cycle (CBC operates with helium as WF, while the bottoming RC is operated with one of the following WFs: carbon dioxide, xenon, ethane, ammonia, or water. In both cases, an intermediate heat exchanger (IHE is proposed to provide thermal energy to the closed Brayton or to the Rankine cycles. The results of the case study show that the thermal efficiency, through the use of a CC, is slightly improved (from 45.79% for BC and from 50.17% for RC to 53.63 for the proposed CC with He-H2O operating under safety standards.

  6. AKUT-II: an experimental plant for purifying the HTR loop of combustion waste gas

    Energy Technology Data Exchange (ETDEWEB)

    Beaujean, H.; Vygen, H.

    1976-02-15

    A plant for the separation of aerosols, krypton and tritium (AKUT) used for purifying the head end of the reprocessing of thorium-containing fuel elements from combustion waste gases is described. Data are to be collected to enable a process engineer to plan and construct a large-scale plant, and the correctness and practicability of the concept adopted is to be proved in conjunction with the JUPITER plant. It is true that the tests on the AKUT I plant confirmed that the flow scheme was basically correct, but the actual experimental operation was considerably limited by a fixed and rigid coupling to the combustion furnace. Some operational conditions were encountered which did not meet the design values. Part of the plant (krypton separation) is being tested in the USA. The German concept was taken over in the early stages of tests and adapted to existing apparatuses, the result inevitably being different experimental conditions. The AKUT II plant can now be used for consideration of the economic and safety conditions, and comparisons can be made.

  7. A Small-Sized HTGR System Design for Multiple Heat Applications for Developing Countries

    Directory of Open Access Journals (Sweden)

    Hirofumi Ohashi

    2013-01-01

    Full Text Available Japan Atomic Energy Agency has conducted a conceptual design of a 50 MWt small-sized high temperature gas cooled reactor (HTGR for multiple heat applications, named HTR50S, with the reactor outlet coolant temperature of 750°C and 900°C. It is first-of-a-kind of the commercial plant or a demonstration plant of a small-sized HTGR system to be deployed in developing countries in the 2020s. The design concept of HTR50S is to satisfy the user requirements for multipurpose heat applications such as the district heating and process heat supply based on the steam turbine system and the demonstration of the power generation by helium gas turbine and the hydrogen production using the water splitting iodine-sulfur process, to upgrade its performance compared to that of HTTR without significant R&D utilizing the knowledge obtained by the HTTR design and operation, and to fulfill the high level of safety by utilizing the inherent features of HTGR and a passive decay heat removal system. The evaluation of technical feasibility shows that all design targets were satisfied by the design of each system and the preliminary safety analysis. This paper describes the conceptual design and the preliminary safety analysis of HTR50S.

  8. Core physics analysis of 100% MOX Core in IRIS

    Energy Technology Data Exchange (ETDEWEB)

    Franceschini, F.; Petrovic, B. [Westinghouse Electric Company LLC, Science and Technology Dept., 1344 Beulah Road, Pittsburgh, PA 15235 (United States)

    2006-07-01

    International Reactor Innovative and Secure (IRIS) is an advanced small-to-medium-size (1000 MWt) Pressurized Water Reactor (PWR), targeting deployment around 2015. Its reference core design is based on the current Westinghouse UO{sub 2} fuel with less than 5% {sup 235}U, and the analysis has been previously completed confirming good performance. The full MOX fuel core is currently under evaluation as one of the alternatives for the second wave of IRIS reactors. A full 3-D neutronic analysis has been performed to examine main core performance parameters, such as critical boron concentration, peaking factors, discharge burnup, etc. The enhanced moderation of the IRIS fuel lattice facilitates MOX core design, and all the obtained results are within the requirements, confirming viability of this option from the reactor physics standpoint. (authors)

  9. A candidate gene study of serotonergic pathway genes and pain relief during treatment with escitalopram in patients with neuropathic pain shows significant association to serotonin receptor2C (HTR2C)

    DEFF Research Database (Denmark)

    Brasch-Andersen, Charlotte; Møller, Malik U; Christiansen, Lene

    2011-01-01

    PURPOSE: Previous studies have shown that a small fraction of patients with peripheral neuropathic pain experiences >50% pain relief during treatment with selective serotonin reuptake inhibitors (SSRIs), whereas most patients have no or only slight relief. The aim of this study was to investigate...... receptor 2A (HTR2A) gene, the serotonin receptor 2C (HTR2C) gene, the ABCB1 gene encoding for the P-glycoprotein, the CYP2C19 gene, and the serotonin transporter gene (SLC6A4). RESULTS: The SNP rs6318 (Cys23Ser) in the HTR2C gene showed significant association with treatment response in men (p = 0...... with increasing number of short alleles for the 5-HTTLPR polymorphism of the serotonin transporter (OR 5.7, p = 0.057). None of the other polymorphisms showed a significant association with treatment response to escitalopram. CONCLUSION: This study indicates that variation in the HTR2C gene is associated...

  10. A putatively functional polymorphism in the HTR2C gene is associated with depressive symptoms in white females reporting significant life stress.

    Directory of Open Access Journals (Sweden)

    Beverly H Brummett

    Full Text Available Psychosocial stress is well known to be positively associated with subsequent depressive symptoms. Cortisol response to stress may be one of a number of biological mechanisms that links psychological stress to depressive symptoms, although the precise causal pathway remains unclear. Activity of the x-linked serotonin 5-HTR2C receptor has also been shown to be associated with depression and with clinical response to antidepressant medications. We recently demonstrated that variation in a single nucleotide polymorphism on the HTR2C gene, rs6318 (Ser23Cys, is associated with different cortisol release and short-term changes in affect in response to a series of stress tasks in the laboratory. Based on this observation, we decided to examine whether rs6318 might moderate the association between psychosocial stress and subsequent depressive symptoms. In the present study we use cross-sectional data from a large population-based sample of young adult White men (N = 2,366 and White women (N = 2,712 in the United States to test this moderation hypothesis. Specifically, we hypothesized that the association between self-reported stressful life events and depressive symptoms would be stronger among homozygous Ser23 C females and hemizygous Ser23 C males than among Cys23 G carriers. In separate within-sex analyses a genotype-by-life stress interaction was observed for women (p = .022 but not for men (p = .471. Homozygous Ser23 C women who reported high levels of life stress had depressive symptom scores that were about 0.3 standard deviations higher than female Cys23 G carriers with similarly high stress levels. In contrast, no appreciable difference in depressive symptoms was observed between genotypes at lower levels of stress. Our findings support prior work that suggests a functional SNP on the HTR2C gene may confer an increased risk for depressive symptoms in White women with a history of significant life stress.

  11. Recruitment by the Repressor Freud-1 of Histone Deacetylase-Brg1 Chromatin Remodeling Complexes to Strengthen HTR1A Gene Repression

    Science.gov (United States)

    Souslova, Tatiana; Mirédin, Kim; Millar, Anne M.

    2017-01-01

    Five-prime repressor element under dual repression binding protein-1 (Freud-1)/CC2D1A is genetically linked to intellectual disability and implicated in neuronal development. Freud-1 represses the serotonin-1A (5-HT1A) receptor gene HTR1A by histone deacetylase (HDAC)-dependent or HDAC-independent mechanisms in 5-HT1A-negative (e.g., HEK-293) or 5-HT1A-expressing cells (SK-N-SH), respectively. To identify the underlying mechanisms, Freud-1-associated proteins were affinity-purified from HEK-293 nuclear extracts and members of the Brg1/SMARCCA chromatin remodeling and Sin3A-HDAC corepressor complexes were identified. Pull-down assays using recombinant proteins showed that Freud-1 interacts directly with the Brg1 carboxyl-terminal domain; interaction with Brg1 required the carboxyl-terminal of Freud-1. Freud-1 complexes in HEK-293 and SK-N-SH cells differed, with low levels of BAF170/SMARCC2 and BAF57/SMARCE1 in HEK-293 cells and low-undetectable BAF155/SMARCC1, Sin3A, and HDAC1/2 in SK-N-SH cells. Similarly, by quantitative chromatin immuno-precipitation, Brg1-BAF170/57 and Sin3A-HDAC complexes were observed at the HTR1A promoter in HEK-293 cells, whereas in SK-N-SH cells, Sin3A-HDAC proteins were not detected. Quantifying 5-HT1A receptor mRNA levels in cells treated with siRNA to Freud-1, Brg1, or both RNAs addressed the functional role of the Freud-1-Brg1 complex. In HEK-293 cells, 5-HT1A receptor mRNA levels were increased only when both Freud-1 and Brg1 were depleted, but in SK-N-SH cells, depletion of either protein upregulated 5-HT1A receptor RNA. Thus, recruitment by Freud-1 of Brg1, BAF155, and Sin3A-HDAC complexes appears to strengthen repression of the HTR1A gene to prevent its expression inappropriate cell types, while recruitment of the Brg1-BAF170/57 complex is permissive to 5-HT1A receptor expression. Alterations in Freud-1-Brg1 interactions in mutants associated with intellectual disability could impair gene repression leading to altered neuronal

  12. Recruitment by the Repressor Freud-1 of Histone Deacetylase-Brg1 Chromatin Remodeling Complexes to Strengthen HTR1A Gene Repression.

    Science.gov (United States)

    Souslova, Tatiana; Mirédin, Kim; Millar, Anne M; Albert, Paul R

    2017-12-01

    Five-prime repressor element under dual repression binding protein-1 (Freud-1)/CC2D1A is genetically linked to intellectual disability and implicated in neuronal development. Freud-1 represses the serotonin-1A (5-HT1A) receptor gene HTR1A by histone deacetylase (HDAC)-dependent or HDAC-independent mechanisms in 5-HT1A-negative (e.g., HEK-293) or 5-HT1A-expressing cells (SK-N-SH), respectively. To identify the underlying mechanisms, Freud-1-associated proteins were affinity-purified from HEK-293 nuclear extracts and members of the Brg1/SMARCCA chromatin remodeling and Sin3A-HDAC corepressor complexes were identified. Pull-down assays using recombinant proteins showed that Freud-1 interacts directly with the Brg1 carboxyl-terminal domain; interaction with Brg1 required the carboxyl-terminal of Freud-1. Freud-1 complexes in HEK-293 and SK-N-SH cells differed, with low levels of BAF170/SMARCC2 and BAF57/SMARCE1 in HEK-293 cells and low-undetectable BAF155/SMARCC1, Sin3A, and HDAC1/2 in SK-N-SH cells. Similarly, by quantitative chromatin immunoprecipitation, Brg1-BAF170/57 and Sin3A-HDAC complexes were observed at the HTR1A promoter in HEK-293 cells, whereas in SK-N-SH cells, Sin3A-HDAC proteins were not detected. Quantifying 5-HT1A receptor mRNA levels in cells treated with siRNA to Freud-1, Brg1, or both RNAs addressed the functional role of the Freud-1-Brg1 complex. In HEK-293 cells, 5-HT1A receptor mRNA levels were increased only when both Freud-1 and Brg1 were depleted, but in SK-N-SH cells, depletion of either protein upregulated 5-HT1A receptor RNA. Thus, recruitment by Freud-1 of Brg1, BAF155, and Sin3A-HDAC complexes appears to strengthen repression of the HTR1A gene to prevent its expression inappropriate cell types, while recruitment of the Brg1-BAF170/57 complex is permissive to 5-HT1A receptor expression. Alterations in Freud-1-Brg1 interactions in mutants associated with intellectual disability could impair gene repression leading to altered neuronal

  13. An Innovative Three-Dimensional Heterogeneous Coarse-Mesh Transport Method for Advanced and Generation IV Reactor Core Analysis and Design

    Energy Technology Data Exchange (ETDEWEB)

    Farzad Rahnema

    2009-11-12

    This project has resulted in a highly efficient method that has been shown to provide accurate solutions to a variety of 2D and 3D reactor problems. The goal of this project was to develop (1) an accurate and efficient three-dimensional whole-core neutronics method with the following features: based sollely on transport theory, does not require the use of cross-section homogenization, contains a highly accurate and self-consistent global flux reconstruction procedure, and is applicable to large, heterogeneous reactor models, and to (2) create new numerical benchmark problems for code cross-comparison.

  14. Design

    DEFF Research Database (Denmark)

    Volf, Mette

    This publication is unique in its demystification and operationalization of the complex and elusive nature of the design process. The publication portrays the designer’s daily work and the creative process, which the designer is a part of. Apart from displaying the designer’s work methods...... and design parameters, the publication shows examples from renowned Danish design firms. Through these examples the reader gets an insight into the designer’s reality....

  15. Association between the HTR2C rs1414334 C/G gene polymorphism and the development of the metabolic syndrome in patients treated with atypical antipsychotics

    Directory of Open Access Journals (Sweden)

    José María Rico-Gomis

    2016-07-01

    Full Text Available Few studies have assessed the association between the rs1414334 C/G polymorphism in the HTR2C gene and the development of the metabolic syndrome in patients treated with atypical antipsychotics. To provide further evidence, a cross-sectional study was conducted in Spain between 2012 and 2013 in 166 patients with these characteristics. In these patients, the association between the polymorphism and the presence of the metabolic syndrome was determined by implementing binary logistic regression models adjusted for variables associated with the metabolic syndrome. We did not confirm previous claims that the C allele of the polymorphism was linked to the metabolic syndrome: the association was in the opposite direction and non-significant. This conclusion held after taking gender and lifestyle variables into account.

  16. Risk and protective genetic variants in suicidal behaviour: association with SLC1A2, SLC1A3, 5-HTR1B &NTRK2 polymorphisms

    Directory of Open Access Journals (Sweden)

    Buckley Avril

    2011-06-01

    Full Text Available Abstract Background Suicidal behaviour is known to aggregate in families. Patients with psychiatric disorders are at higher risk for suicide attempts (SA, however protective and risk genetic variants for suicide appear to be independent of underlying psychiatric disorders. Here we