WorldWideScience

Sample records for high burnup reactivity

  1. Burnup Credit of Erbia Super-High-Burnup Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Sugimura, Naoki; Imamura, Michitaka; Mori, Masaaki [Nuclear Engineering, Ltd., Osaka (Japan); Yamasaki, Masatoshi [Nuclear Fuel Industries, Ltd., Osaka (Japan)

    2008-07-01

    Based on the concept of the Erbia bearing Super High-Burnup (Er-SHB) fuel, the initial erbia contents to guarantee the lower reactivity than that of the conventional 5.0 wt% enriched UO{sub 2} fuels during burnup and cooling are studied. According to the results, the feasibility of the commercial PWR cores using Er-SHB fuels is verified. As the results, it is verified that the long life core operation using Er-SHB fuel are feasible and approximately 20% of feed fuel assemblies can be saved by using Er-SHB fuel. (authors)

  2. Effect of fuel burnup and cross sections on modular HTGR (High-Temperature Gas-cooled Reactor) reactivity coefficients

    Science.gov (United States)

    Lefler, W.; Baxter, A.; Mathews, D.

    1987-12-01

    The temperature dependence of the reactivity coefficient in a prismatic block Modular High-Temperature Gas-Cooled Reactor (MHTGR) design is examined and found to be large and negative. Temperature coefficient results obtained with the ENDF/B-V data library were almost the same as results obtained with the earlier versions of the ENDF/B data library usually used at GA Technologies Inc., in spite of a significant eigenvalue increase with the ENDF/B-V data. The effects of fuel burnup and arbitrarily assumed cross section variations were examined and tabulated.

  3. Reactivity loss validation of high burn-up PWR fuels with pile-oscillation experiments in MINERVE

    Energy Technology Data Exchange (ETDEWEB)

    Leconte, P.; Vaglio-Gaudard, C.; Eschbach, R.; Di-Salvo, J.; Antony, M.; Pepino, A. [CEA, DEN, DER, Cadarache, F-13108 Saint-Paul-Lez-Durance (France)

    2012-07-01

    The ALIX experimental program relies on the experimental validation of the spent fuel inventory, by chemical analysis of samples irradiated in a PWR between 5 and 7 cycles, and also on the experimental validation of the spent fuel reactivity loss with bum-up, obtained by pile-oscillation measurements in the MINERVE reactor. These latter experiments provide an overall validation of both the fuel inventory and of the nuclear data responsible for the reactivity loss. This program offers also unique experimental data for fuels with a burn-up reaching 85 GWd/t, as spent fuels in French PWRs never exceeds 70 GWd/t up to now. The analysis of these experiments is done in two steps with the APOLLO2/SHEM-MOC/CEA2005v4 package. In the first one, the fuel inventory of each sample is obtained by assembly calculations. The calculation route consists in the self-shielding of cross sections on the 281 energy group SHEM mesh, followed by the flux calculation by the Method Of Characteristics in a 2D-exact heterogeneous geometry of the assembly, and finally a depletion calculation by an iterative resolution of the Bateman equations. In the second step, the fuel inventory is used in the analysis of pile-oscillation experiments in which the reactivity of the ALIX spent fuel samples is compared to the reactivity of fresh fuel samples. The comparison between Experiment and Calculation shows satisfactory results with the JEFF3.1.1 library which predicts the reactivity loss within 2% for burn-up of {approx}75 GWd/t and within 4% for burn-up of {approx}85 GWd/t. (authors)

  4. Alloy development for high burnup cladding (PWR)

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, R. [Kraftwerk Union AG, Mulheim (Germany); Jeong, Y.H.; Baek, K.H.; Kim, S.J.; Choi, B.K.; Kim, J.M. [Korea Atomic Energy Research Institute, Taejon (Korea, Republic of)

    1999-04-01

    An overview on current alloy development for high burnup PWR fuel cladding is given. It is mainly based on literature data. First, the reasons for an increase of the current mean discharge burnup from 35 MWd / kg(U) to 70 MWd / kg(U) are outlined. From the material data, it is shown that a batch average burnup of 60-70 MWd / kg(U), as aimed by many fuel vendors, can not be achieved with stand (=ASTM-) Zry-4 cladding tubes without violating accepted design criteria. Specifically criteria which limit maximum oxide scale thickness and maximum hydrogen content, and to a less degree, maximum creep and growth rate, can not be achieved. The development potential of standard Zry-4 is shown. Even when taking advantage of this potential, it is shown that an 'improved' Zry-4 is reaching its limits when it achieves the target burnup. The behavior of some Zr alloys outside the ASTM range is shown, and the advantages and disadvantages of the 3 alloy groups (ZrSn+transition metals, ZrNb, ZrSnNb+transition metals) which are currently considered to have the development potential for high burnup cladding materials are depicted. Finally, conclusions are drawn. (author). 14 refs., 11 tabs., 82 figs.

  5. High Burnup Fuel Performance and Safety Research

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Je Keun; Lee, Chan Bok; Kim, Dae Ho (and others)

    2007-03-15

    The worldwide trend of nuclear fuel development is to develop a high burnup and high performance nuclear fuel with high economies and safety. Because the fuel performance evaluation code, INFRA, has a patent, and the superiority for prediction of fuel performance was proven through the IAEA CRP FUMEX-II program, the INFRA code can be utilized with commercial purpose in the industry. The INFRA code was provided and utilized usefully in the universities and relevant institutes domesticallly and it has been used as a reference code in the industry for the development of the intrinsic fuel rod design code.

  6. Summary of high burnup fuel issues and NRC`s plan of action

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, R.O.

    1997-01-01

    For the past two years the Office of Nuclear Regulatory Research has concentrated mostly on the so-called reactivity-initiated accidents -- the RIAs -- in this session of the Water Reactor Safety Information Meeting, but this year there is a more varied agenda. RIAs are, of course, not the only events of interest for reactor safety that are affected by extended burnup operation. Their has now been enough time to consider a range of technical issues that arise at high burnup, and a list of such issues being addressed in their research program is given here. (1) High burnup capability of the steady-state code (FRAPCON) used for licensing audit calculations. (2) General capability (including high burnup) of the transient code (FRAPTRAN) used for special studies. (3) Adequacy at high burnup of fuel damage criteria used in regulation for reactivity accidents. (4) Adequacy at high burnup of models and fuel related criteria used in regulation for loss-of-coolant accidents (LOCAs). (5) Effect of high burnup on fuel system damage during normal operation, including control rod insertion problems. A distinction is made between technical issues, which may or may not have direct licensing impacts, and licensing issues. The RIAs became a licensing issue when the French test in CABRI showed that cladding failures could occur at fuel enthalpies much lower than a value currently used in licensing. Fuel assembly distortion became a licensing issue when control rod insertion was affected in some operating plants. In this presentation, these technical issues will be described and the NRC`s plan of action to address them will be discussed.

  7. Impact investigation of reactor fuel operating parameters on reactivity for use in burnup credit applications

    Science.gov (United States)

    Sloma, Tanya Noel

    When representing the behavior of commercial spent nuclear fuel (SNF), credit is sought for the reduced reactivity associated with the net depletion of fissile isotopes and the creation of neutron-absorbing isotopes, a process that begins when a commercial nuclear reactor is first operated at power. Burnup credit accounts for the reduced reactivity potential of a fuel assembly and varies with the fuel burnup, cooling time, and the initial enrichment of fissile material in the fuel. With regard to long-term SNF disposal and transportation, tremendous benefits, such as increased capacity, flexibility of design and system operations, and reduced overall costs, provide an incentive to seek burnup credit for criticality safety evaluations. The Nuclear Regulatory Commission issued Interim Staff Guidance 8, Revision 2 in 2002, endorsing burnup credit of actinide composition changes only; credit due to actinides encompasses approximately 30% of exiting pressurized water reactor SNF inventory and could potentially be increased to 90% if fission product credit were accepted. However, one significant issue for utilizing full burnup credit, compensating for actinide and fission product composition changes, is establishing a set of depletion parameters that produce an adequately conservative representation of the fuel's isotopic inventory. Depletion parameters can have a significant effect on the isotopic inventory of the fuel, and thus the residual reactivity. This research seeks to quantify the reactivity impact on a system from dominant depletion parameters (i.e., fuel temperature, moderator density, burnable poison rod, burnable poison rod history, and soluble boron concentration). Bounding depletion parameters were developed by statistical evaluation of a database containing reactor operating histories. The database was generated from summary reports of commercial reactor criticality data. Through depletion calculations, utilizing the SCALE 6 code package, several light

  8. Advances in Metallic Fuels for High Burnup and Actinide Transmutation

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, S. L.; Harp, J. M.; Chichester, H. J. M.; Fielding, R. S.; Mariani, R. D.; Carmack, W. J.

    2016-10-01

    Research and development activities on metallic fuels in the US are focused on their potential use for actinide transmutation in future sodium fast reactors. As part of this application, there is a desire to demonstrate a multifold increase in burnup potential. A number of metallic fuel design innovations are under investigation with a view toward significantly increasing the burnup potential of metallic fuels, since higher discharge burnups equate to lower potential actinide losses during recycle. Promising innovations under investigation include: 1) lowering the fuel smeared density in order to accommodate the additional swelling expected as burnups increase, 2) utilizing an annular fuel geometry for better geometrical stability at low smeared densities, as well as the potential to eliminate the need for a sodium bond, and 3) minor alloy additions to immobilize lanthanide fission products inside the metallic fuel matrix and prevent their transport to the cladding resulting in fuel-cladding chemical interaction. This paper presents results from these efforts to advance metallic fuel technology in support of high burnup and actinide transmutation objectives. Highlights include examples of fabrication of low smeared density annular metallic fuels, experiments to identify alloy additions effective in immobilizing lanthanide fission products, and early postirradiation examinations of annular metallic fuels having low smeared densities and palladium additions for fission product immobilization.

  9. Technical Basis for Peak Reactivity Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, William BJ J [ORNL; Ade, Brian J [ORNL; Bowman, Stephen M [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Mertyurek, Ugur [ORNL; Radulescu, Georgeta [ORNL

    2015-01-01

    Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate application of burnup credit for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase (1) investigates applicability of peak reactivity methods currently used in spent fuel pools (SFPs) to storage and transportation systems and (2) evaluates validation of both reactivity (keff) calculations and burnup credit nuclide concentrations within these methods. The second phase will focus on extending burnup credit beyond peak reactivity. This paper documents the first phase, including an analysis of lattice design parameters and depletion effects, as well as both validation components. Initial efforts related to extended burnup credit are discussed in a companion paper. Peak reactivity analyses have been used in criticality analyses for licensing of BWR fuel in SFPs over the last 20 years. These analyses typically combine credit for the gadolinium burnable absorber present in the fuel with a modest amount of burnup credit. Gadolinium burnable absorbers are used in BWR assemblies to control core reactivity. The burnable absorber significantly reduces assembly reactivity at beginning of life, potentially leading to significant increases in assembly reactivity for burnups less than 15–20 GWd/MTU. The reactivity of each fuel lattice is dependent on gadolinium loading. The number of gadolinium-bearing fuel pins lowers initial lattice reactivity, but it has a small impact on the burnup and reactivity of the peak. The gadolinium concentration in each pin has a small impact on initial lattice reactivity but a significant effect on the reactivity of the peak and the burnup at which the peak occurs. The importance of the lattice parameters and depletion conditions are primarily determined by their impact on the gadolinium depletion. Criticality code validation for BWR burnup

  10. Analysis of high burnup pressurized water reactor fuel using uranium, plutonium, neodymium, and cesium isotope correlations with burnup

    Directory of Open Access Journals (Sweden)

    Jung Suk Kim

    2015-12-01

    Full Text Available The correlation of the isotopic composition of uranium, plutonium, neodymium, and cesium with the burnup for high burnup pressurized water reactor fuels irradiated in nuclear power reactors has been experimentally investigated. The total burnup was determined by Nd-148 and the fractional 235U burnup was determined by U and Pu mass spectrometric methods. The isotopic compositions of U, Pu, Nd, and Cs after their separation from the irradiated fuel samples were measured using thermal ionization mass spectrometry. The contents of these elements in the irradiated fuel were determined through an isotope dilution mass spectrometric method using 233U, 242Pu, 150Nd, and 133Cs as spikes. The activity ratios of Cs isotopes in the fuel samples were determined using gamma-ray spectrometry. The content of each element and its isotopic compositions in the irradiated fuel were expressed by their correlation with the total and fractional burnup, burnup parameters, and the isotopic compositions of different elements. The results obtained from the experimental methods were compared with those calculated using the ORIGEN-S code.

  11. Investigation and basic evaluation for ultra-high burnup fuel cladding material

    Energy Technology Data Exchange (ETDEWEB)

    Ioka, Ikuo; Nagase, Fumihisa; Futakawa, Masatoshi; Kiuchi, Kiyoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Suga, Masataka [Kokan Keisoku Co., Kawasaki, Kanagawa (Japan)

    2001-03-01

    In ultra-high burnup of the power reactor, it is an essential problem to develop the cladding with excellent durability. First, development history and approach of the safety assessment of Zircaloy for the high burnup fuel were summarized in the report. Second, the basic evaluation and investigation were carried out on the material with high practicability in order to select the candidate materials for the ultra-high burnup fuel. In addition, the basic research on modification technology of the cladding surface was carried out from the viewpoint of the addition of safety margin as a cladding. From the development history of the zirconium alloy including the Zircaloy, it is hard to estimate the results of in-pile test from those of the conventional corrosion test (out-pile test). Therefore, the development of the new testing technology that can simulate the actual environment and the elucidation of the corrosion-controlling factor of the cladding are desired. In cases of RIA (Reactivity Initiated Accident) and LOCA (Loss of Coolant Accident), it seems that the loss of ductility in zirconium alloys under heavy irradiation and boiling of high temperature water restricts the extension of fuel burnup. From preliminary evaluation on the high corrosion-resistance materials (austenitic stainless steel, iron or nickel base superalloys, titanium alloy, niobium alloy, vanadium alloy and ferritic stainless steel), stabilized austenitic stainless steels with a capability of future improvement and high-purity niobium alloys with a expectation of the good corrosion resistance were selected as candidate materials of ultra-high burnup cladding. (author)

  12. The Gd-isotopic fuel for high burnup in PWR's

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Marcio Soares; Mattos, João Roberto L. de; Andrade, Edison Pereira de, E-mail: marciod@cdtn.br, E-mail: jrmattos@cdtn.br, E-mail: epa@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2017-07-01

    Today, the discussion about the high burnup fuel is beyond the current fuel enrichment licensing and burnup limits. Licensing issues and material/design developments are again key features in further development of the LWR fuel design. Nevertheless, technological and economical solutions are already available or will be available in a short time. In order to prevent the growth of the technological gap, Brazil's nuclear sector needs to invest in the training of new human resources, in the access to international databases, and in the upgrading existing infrastructure. Experimental database and R&D infrastructure are essential components to support the autonomous development of Brazilian Nuclear Reactors, promoting the development of national technologies. The (U,Gd)O{sub 2} isotopic fuel proposed by the CDTN's staff solve two main issues in the high burnup fuel, which are (1) the peak of reactivity resulting from the Gd-157 fast burnup, and (2) the peak of temperature in the (U,Gd)O{sub 2} nuclear fuel resulting from detrimental effects in the thermal properties for gadolinia additions higher than 2%. A sustainable future can be envisaged for the nuclear energy. (author)

  13. Models for fuel rod behaviour at high burnup

    Energy Technology Data Exchange (ETDEWEB)

    Jernkvist, Lars O.; Massih, Ali R. [Quantum Technologies AB, Uppsala Science Park, Uppsala (Sweden)

    2004-12-01

    This report deals with release of fission product gases and irradiation-induced restructuring in uranium dioxide nuclear fuel. Waterside corrosion of zirconium alloy clad tubes to light water reactor fuel rods is also discussed. Computational models, suitable for implementation in the FRAPCON-3.2 computer code, are proposed for these potentially life-limiting phenomena. Hence, an integrated model for the calculation or thermal fission gas release by intragranular diffusion, gas trapping in grain boundaries, irradiation-induced re-solution, grain boundary saturation, and grain boundary sweeping in UO{sub 2} fuel, under time varying temperature loads, is formulated. After a brief review of the status of thermal fission gas release modelling, we delineate the governing equations for the aforementioned processes. Grain growth kinetic modelling is briefly reviewed and pertinent data on grain growth of high burnup fuel obtained during power ramps in the Third Risoe Fission Gas Release Project are evaluated. Sample computations are performed, which clearly show the connection between fission gas release and gram growth as a function of time at different isotherms. Models are also proposed for the restructuring of uranium dioxide fuel at high burnup, the so-called rim formation, and its effect on fuel porosity build-up, fuel thermal conductivity and fission gas release. These models are assessed by use of recent experimental data from the High Burnup Rim Project, as well as from post irradiation examinations of high-burnup fuel, irradiated in power reactors. Moreover, models for clad oxide growth and hydrogen pickup in PWRs, applicable to Zircaloy-4, ZIRLO or M5 cladding, are formulated, based on recent in-reactor corrosion data for high-burnup fuel rods. Our evaluation of these data indicates that the oxidation rate of ZIRLO-type materials is about 20% lower than for standard Zircaloy-4 cladding under typical PWR conditions. Likewise, the oxidation rate of M5 seems to be

  14. Study on nuclear physics of high burnup full MOX PWR core

    Energy Technology Data Exchange (ETDEWEB)

    Kugo, Teruhiko; Shimada, Syoichiro; Okubo, Tsutomu; Ochiai, Masaaki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-10-01

    As one of options for future light water reactors, we have been studying a new concept of a high burnup full MOX PWR core. We have proposed a core of 600 MWe to ensure discharged burnup of 100 GWd/t by increasing a moderator to fuel volume ratio to 2.6 with enlarged fuel pin pitch of 13.8 mm, and have investigated its feasibility in neutronics. A plutonium fissile content of 12% is needed for this core. A soluble boric acid with B-10 enrichment of 40% is able to control burnup reactivity without increasing a capacity of boron tanks. A control rod cluster with use of natural boron carbide (B{sub 4}C) per three fuel assemblies ensures a shutdown margin of more than 2%dk/kk`. A moderator temperature and void coefficients are negative through an operating cycle. Although the use of burnable poisons like Gd{sub 2}O{sub 3} and Er{sub 2}O{sub 3} is not necessary to reduce an excess reactivity, it can lower a radial power peaking factor by about 0.1. (author)

  15. Modelling of fission gas swelling in the high burnup UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Ho; Lee, Chan Bock; Bang, Je Gun; Jung, Yeon Ho

    1999-06-01

    Discharge burnup of the fuel in LWR has been increased to improve the fuel economy, and currently the high burnup fuel of over 70 MWd/kg U-rod avg. is being developed by the fuel vendors worldwide. At high burnup, thermal / mechanical properties of the fuel is known to change and new phenomenon could arise. This report describes the model development on fission gas swelling in high burnup UO{sub 2} fuel. For the low burnup fuel, swelling only by the solid fission products has been considered in the fuel performance analysis. However, at high burnup fuel, swelling by fission gas bubbles can not be neglected anymore. Therefore, fission gas swelling model which can predictbubble swelling of the high burnup UO{sub 2} fuel during the steady-state and the transient conditions in LWR was developed. Based on the bubble growth model, the empirical fission gas swelling model was developed as function of burnup, time and temperature. The model showed that fuel bubble swelling would be proportional to the burnup by the power of 1.157 and to the time by the power of 0.157. Comparison of the model prediction with the measured fission gas swelling data under the various burnup and temperature conditions showed that the model would predict the measured data reasonably well. (author). 20 refs., 8 tabs., 17 figs.

  16. Impact of Reactor Operating Parameters on Cask Reactivity in BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ilas, Germina [ORNL; Betzler, Benjamin R [ORNL; Ade, Brian J [ORNL

    2017-01-01

    This paper discusses the effect of reactor operating parameters used in fuel depletion calculations on spent fuel cask reactivity, with relevance for boiling-water reactor (BWR) burnup credit (BUC) applications. Assessments that used generic BWR fuel assembly and spent fuel cask configurations are presented. The considered operating parameters, which were independently varied in the depletion simulations for the assembly, included fuel temperature, bypass water density, specific power, and operating history. Different operating history scenarios were considered for the assembly depletion to determine the effect of relative power distribution during the irradiation cycles, as well as the downtime between cycles. Depletion, decay, and criticality simulations were performed using computer codes and associated nuclear data within the SCALE code system. Results quantifying the dependence of cask reactivity on the assembly depletion parameters are presented herein.

  17. Mechanical Fatigue Testing of High Burnup Fuel for Transportation Applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-01

    This report describes testing designed to determine the ability of high burnup (HBU) (>45 GWd/MTU) spent fuel to maintain its integrity under normal conditions of transportation. An innovative system, Cyclic Integrated Reversible-bending Fatigue Tester (CIRFT), has been developed at Oak Ridge National Laboratory (ORNL) to test and evaluate the mechanical behavior of spent nuclear fuel (SNF) under conditions relevant to storage and transportation. The CIRFT system is composed of a U-frame equipped with load cells for imposing the pure bending loads on the SNF rod test specimen and measuring the in-situ curvature of the fuel rod during bending using a set up with three linear variable differential transformers (LVDTs).

  18. Detailed description and user`s manual of high burnup fuel analysis code EXBURN-I

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Saitou, Hiroaki

    1997-11-01

    EXBURN-I has been developed for the analysis of LWR high burnup fuel behavior in normal operation and power transient conditions. In the high burnup region, phenomena occur which are different in quality from those expected for the extension of behaviors in the mid-burnup region. To analyze these phenomena, EXBURN-I has been formed by the incorporation of such new models as pellet thermal conductivity change, burnup-dependent FP gas release rate, and cladding oxide layer growth to the basic structure of low- and mid-burnup fuel analysis code FEMAXI-IV. The present report describes in detail the whole structure of the code, models, and materials properties. Also, it includes a detailed input manual and sample output, etc. (author). 55 refs.

  19. Performance limitations for PWR fuel burnup extensions and high burnup complex loading patterns; Esquemas de recarga de combustible de alto quemado y limitaciones asociadas

    Energy Technology Data Exchange (ETDEWEB)

    Ahnert, C.; Aragones, J. M.; Cabellos, O.; Garcia Herranz, N. [Universidad Politecnica de Madrid (Spain)

    2000-07-01

    The analysis, design and on-line surveillance of pressurized water reactors require extensive and detailed 3D core calculations. The development and the improvement of codes are required due to the increasing heterogeneity in PWR (new type of fuel assemblies, complex loading patterns and safety and reliability requirements of nuclear reactor operation). The SEANAP system has been extensively validated and this system has been used to analyze high burnup fuel specifications and several types of long cycles. Some Programs (with Spanish participation) have been developed to study limitations for fuel burnup extensions: Robust Fuel Program, Segmented Rods Program and gain regulatory acceptance of fuel design and operation to higher burnup levels. (Author)

  20. High Burn-Up Spent Nuclear Fuel Vibration Integrity Study

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Wang, Hong [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jiang, Hao [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Howard, Rob L [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Scaglione, John M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-01-01

    The Oak Ridge National Laboratory (ORNL) has developed the cyclic integrated reversible-bending fatigue tester (CIRFT) approach to successfully demonstrate the controllable fatigue fracture on high burnup (HBU) spent nuclear fuel (SNF) in a normal vibration mode. CIRFT enables examination of the underlying mechanisms of SNF system dynamic performance. Due to the inhomogeneous composite structure of the SNF system, the detailed mechanisms of the pellet-pellet and pellet-clad interactions and the stress concentration effects at the pellet-pellet interface cannot be readily obtained from a CIRFT system measurement. Therefore, finite element analyses (FEAs) are used to translate the global moment-curvature measurement into local stress-strain profiles for further investigation. The major findings of CIRFT on the HBU SNF are as follows: SNF system interface bonding plays an important role in SNF vibration performance. Fuel structure contributes to SNF system stiffness. There are significant variations in stress and curvature of SNF systems during vibration cycles resulting from segment pellets and clad interactions. SNF failure initiates at the pellet-pellet interface region and appears to be spontaneous.

  1. French investigations of high burnup effect on LOCA thermomecanical behavior. Part two. Oxidation and quenching experiments under simulated LOCA conditions with high burnup clad material

    Energy Technology Data Exchange (ETDEWEB)

    GrandJean, C. [IPSN, Cadarache (France); Cauvin, R.; Lebuffe, C. [EDF/SCMI, Chinon (France)] [and others

    1997-01-01

    In the frame of the high burnup fuel studies to support a possible extension of the current discharge burnup limit, experimental programs have been undertaken, jointly by EDF and IPSN in order to study the thermal-shock behavior of high burnup fuel claddings under typical LOCA conditions. The TAGUS program used unirradiated cladding samples, bare or bearing a pre-corrosion state simulating the end-of-life state of high burnup fuel claddings: the TAGCIR program used actually irradiated cladding samples taken from high burnup rods irradiated over 5 cycles in a commercial EDF PWR and having reached a rod burnup close to 60 GWd/tU. The thermal-shock failure tests consisted in oxidizing the cladding samples under steam flow, on both inner and outer faces or on the outer face alone, and subjecting them to a final water quench. The heating was provided by an inductive furnace the power of which being regulated through monitoring of the sample surface temperature with use of a single-wave optical pyrometer. Analysis of the irradiated tests (TAGCIR series) evidenced an increased oxidation rate as compared to similar tests on unirradiated samples. Results of the quenching tests series on unirradiated and irradiated samples are plotted under the usual presentation of failure maps relative to the oxidation parameters ECR (equivalent cladding reacted) or e{sub {beta}} (thickness of the remaining beta phase layer) as a function of the oxidation temperature. Comparison of the failure limits for irradiated specimens to those for unirradiated specimens indicates a lower brittleness under two side oxidation and possibly the opposite under one-side oxidation. The tentative analysis of the oxidation and quenching tests results on irradiated samples reveals the important role played by the hydrogen charged during in-reactor corrosion on the oxidation kinetics and the failure bearing capability of the cladding under LOCA transient conditions.

  2. Analysis of the behavior under irradiation of high burnup nuclear fuels with the computer programs FRAPCON and FRAPTRAN

    Energy Technology Data Exchange (ETDEWEB)

    Reis, Regis; Silva, Antonio Teixeira e, E-mail: teixeira@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2017-11-01

    The objective of this paper is to verify the validity and accuracy of the results provided by computer programs FRAPCON-3.4a and FRAPTRAN-1.4, used in the simulation process of the irradiation behavior of Pressurized Water Reactors (PWR) fuel rods, in steady-state and transient operational conditions at high burnup. To achieve this goal, the results provided by these computer simulations are compared with experimental data available in the database FUMEX III. Through the results, it was found that the computer programs used have a good ability to predict the operational behavior of PWR fuel rods in high burnup steady-state conditions and under the influence of Reactivity Initiated Accident (RIA). (author)

  3. EPRI/DOE High-Burnup Fuel Sister Rod Test Plan Simplification and Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Saltzstein, Sylvia J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorenson, Ken B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hanson, B. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shimskey, R. W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Klymyshyn, N. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Webster, R. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jensen, P. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); MacFarlan, P. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billone, Mike [Argonne National Lab. (ANL), Argonne, IL (United States); Scaglione, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-09-15

    The EPRI/DOE High-Burnup Confirmatory Data Project (herein called the “Demo”) is a multi-year, multi-entity test with the purpose of providing quantitative and qualitative data to show if high-burnup fuel mechanical properties change in dry storage over a ten-year period. The Demo involves obtaining 32 assemblies of high-burnup PWR fuel of common cladding alloys from the North Anna Nuclear Power Plant, loading them in an NRC-licensed TN-32B cask, drying them according to standard plant procedures, and then storing them on the North Anna dry storage pad for ten years. After the ten-year storage time, the cask will be opened and the mechanical properties of the rods will be tested and analyzed.

  4. Progress of the RIA experiments with high burnup fuels and their evaluation in JAERI

    Energy Technology Data Exchange (ETDEWEB)

    Ishijima, Kiyomi; Fuketa, Toyoshi [Japan Atomic Energy Research Institute, Ibaraki-ken (Japan)

    1997-01-01

    Recent results obtained in the NSRR power burst experiments with high burnup PWR fuel rods are described and discussed in this paper. Data concerning test condition, transient records during pulse irradiation and post irradiation examination are described. Another high burnup PWR fuel rod failed in the test HBO-5 at the slightly higher energy deposition than that in the test HBO-1. The failure mechanism of the test HBO-5 is the same as that of the test HBO-1, that is, hydride-assisted PCMI. Some influence of the thermocouples welding on the failure behavior of the HBO-5 rod was observed.

  5. Post Irradiation Examination Plan for High-Burnup Demonstration Project Sister Rods

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, John M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce Balkcom [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-04-01

    This test plan describes the experimental work to be implemented by the U.S. Department of Energy (DOE) Office of Nuclear Energy (NE) to characterize high burnup (HBU) spent nuclear fuel (SNF) in conjunction with the High Burnup Dry Storage Cask Research and Development Project and serves to coordinate and integrate the multi-year experimental program to collect and develop data regarding the continued storage and eventual transport of HBU (i.e., >45 GWd/MTU) SNF. The work scope involves the development, performance, technical integration, and oversight of measurements and collection of relevant data, guided by analyses and demonstration of need.

  6. Study on core physics characteristics of high burn-up full MOX PWR core. 2

    Energy Technology Data Exchange (ETDEWEB)

    Kugo, Teruhiko; Okubo, Tsutomu; Shimada, Syoichiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-09-01

    As one of options for future light water reactors, we have been studying a new concept of a high burn-up full MOX PWR core with a discharge burn-up of 100 GWd/t and a 3-year operation cycle being based on the existing light water reactor technology. We have already confirmed the feasibility of the core, in which a moderator to fuel volume ratio(Vm/Vf) is increased to 2.6 with the same fuel pin diameter of 9.5 mm as in the current PWR but with the enlarged fuel pin pitch of 13.8 mm. In this report, to improve the neutronics and thermal hydraulic performance of the high burn-up core, we subsequently propose a 600 MWe core ensuring discharge burn-up of 100 GWd/t by increasing Vm/Vf to 3.0 with the same fuel pin pitch of 12.6 mm as in the current PWR and the smaller fuel rod diameter of 8.3 mm instead of 9.5 mm. We have investigated its core characteristics in neutronics and confirmed its feasibility. The core neutronics performance is compared between Vm/Vf = 2.6 and 3.0. From the comparison, it is found that the proposed core with Vm/Vf 3.0 has more promising characteristics than with Vm/Vf = 2.6 such as saving of a fissile plutonium content of 0.3wt%, improvement in a departure from nucleate boiling ratio (DNBR) and so on, except for a shortened cycle length by 9%. In addition, we have investigated a low-leakage refueling scheme for both types of high burn-up cores. Without modification to fuel material such as addition of burnable poison and/or transuranium isotopes, it can not be expected to improve the burn-up efficiency by the low-leakage refueling scheme. (author)

  7. Depletion of gadolinium burnable poison in a PWR assembly with high burnup fuel

    Energy Technology Data Exchange (ETDEWEB)

    Refeat, Riham Mahmoud [Nuclear and Radiological Regulatory Authority (NRRA), Cairo (Egypt). Safety Engineering Dept.

    2015-12-15

    A tendency to increase the discharge burnup of nuclear fuel for Advanced Pressurized Water Reactors (PWR) has been a characteristic of its operation for many years. It will be able to burn at very high burnup of about 70 GWd/t with UO{sub 2} fuels. The U-235 enrichment must be higher than 5 %, which leads to the necessity of using an extremely efficient burnable poison like Gadolinium oxide. Using gadolinium isotope is significant due to its particular depletion behavior (''Onion-Skin'' effect). In this paper, the MCNPX2.7 code is used to calculate the important neutronic parameters of the next generation fuels of PWR. K-infinity, local peaking factor and fission rate distributions are calculated for a PWR assembly which burn at very high burnup reaching 70 GWd/t. The calculations are performed using the recently released evaluated Gadolinium cross section data. The results obtained are close to those of a LWR next generation fuel benchmark problem. This demonstrates that the calculation scheme used is able to accurately model a PWR assembly that operates at high burnup values.

  8. High Burnup Dry Storage Cask Research and Development Project, Final Test Plan

    Energy Technology Data Exchange (ETDEWEB)

    None

    2014-02-27

    EPRI is leading a project team to develop and implement the first five years of a Test Plan to collect data from a SNF dry storage system containing high burnup fuel.12 The Test Plan defined in this document outlines the data to be collected, and the storage system design, procedures, and licensing necessary to implement the Test Plan.13 The main goals of the proposed test are to provide confirmatory data14 for models, future SNF dry storage cask design, and to support license renewals and new licenses for ISFSIs. To provide data that is most relevant to high burnup fuel in dry storage, the design of the test storage system must mimic real conditions that high burnup SNF experiences during all stages of dry storage: loading, cask drying, inert gas backfilling, and transfer to the ISFSI for multi-year storage.15 Along with other optional modeling, SETs, and SSTs, the data collected in this Test Plan can be used to evaluate the integrity of dry storage systems and the high burnup fuel contained therein over many decades. It should be noted that the Test Plan described in this document discusses essential activities that go beyond the first five years of Test Plan implementation.16 The first five years of the Test Plan include activities up through loading the cask, initiating the data collection, and beginning the long-term storage period at the ISFSI. The Test Plan encompasses the overall project that includes activities that may not be completed until 15 or more years from now, including continued data collection, shipment of the Research Project Cask to a Fuel Examination Facility, opening the cask at the Fuel Examination Facility, and examining the high burnup fuel after the initial storage period.

  9. A complete NUHOMS {sup registered} solution for storage and transport of high burnup spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Bondre, J. [Transnuclear, Inc. (AREVA Group), Fremont, CA (United States)

    2004-07-01

    The discharge burnups of spent fuel from nuclear power plants keep increasing with plants discharging or planning to discharge fuel with burnups in excess of 60,000 MWD/MTU. Due to limited capacity of spent fuel pools, transfer of older cooler spent fuel from fuel pool to dry storage, and very limited options for transport of spent fuel, there is a critical need for dry storage of high burnup, higher heat load spent fuel so that plants could maintain their full core offload reserve capability. A typical NUHOMS {sup registered} solution for dry spent fuel storage is shown in the Figure 1. Transnuclear, Inc. offers two advanced NUHOMS {sup registered} solutions for the storage and transportation of high burnup fuel. One includes the NUHOMS {sup registered} 24PTH system for plants with 90.7 Metric Ton (MT) crane capacity; the other offers the higher capacity NUHOMS {sup registered} 32PTH system for higher crane capacity. These systems include NUHOMS {sup registered} - 24PTH and -32PTH Transportable Canisters stored in a concrete storage overpack (HSM-H). These canisters are designed to meet all the requirements of both storage and transport regulations. They are designed to be transported off-site either directly from the spent fuel pool or from the storage overpack in a suitable transport cask.

  10. Modeling of Pore Coarsening in the Rim Region of High Burn-up UO2 Fuel

    Directory of Open Access Journals (Sweden)

    Hongxing Xiao

    2016-08-01

    Full Text Available An understanding of the coarsening process of the large fission gas pores in the high burn-up structure (HBS of irradiated UO2 fuel is very necessary for analyzing the safety and reliability of fuel rods in a reactor. A numerical model for the description of pore coarsening in the HBS based on the Ostwald ripening mechanism, which has successfully explained the coarsening process of precipitates in solids is developed. In this model, the fission gas atoms are treated as the special precipitates in the irradiated UO2 fuel matrix. The calculated results indicate that the significant pore coarsening and mean pore density decrease in the HBS occur upon surpassing a local burn-up of 100 GWd/tM. The capability of this model is successfully validated against irradiation experiments of UO2 fuel, in which the average pore radius, pore density, and porosity are directly measured as functions of local burn-up. Comparisons with experimental data show that, when the local burn-up exceeds 100 GWd/tM, the calculated results agree well with the measured data.

  11. Draft evaluation of the frequency for gas sampling for the high burnup confirmatory data project

    Energy Technology Data Exchange (ETDEWEB)

    Stockman, Christine T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alsaed, Halim A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-26

    This report fulfills the M3 milestone M3FT-15SN0802041, “Draft Evaluation of the Frequency for Gas Sampling for the High Burn-up Storage Demonstration Project” under Work Package FT-15SN080204, “ST Field Demonstration Support – SNL”. This report provides a technically based gas sampling frequency strategy for the High Burnup (HBU) Confirmatory Data Project. The evaluation of: 1) the types and magnitudes of gases that could be present in the project cask and, 2) the degradation mechanisms that could change gas compositions culminates in an adaptive gas sampling frequency strategy. This adaptive strategy is compared against the sampling frequency that has been developed based on operational considerations. Gas sampling will provide information on the presence of residual water (and byproducts associated with its reactions and decomposition) and breach of cladding, which could inform the decision of when to open the project cask.

  12. Evaluation of the Frequency for Gas Sampling for the High Burnup Confirmatory Data Project

    Energy Technology Data Exchange (ETDEWEB)

    Stockman, Christine T. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Alsaed, Halim A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Marschman, Steven C. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Scaglione, John M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-05-01

    This report provides a technically based gas sampling frequency strategy for the High Burnup (HBU) Confirmatory Data Project. The evaluation of: 1) the types and magnitudes of gases that could be present in the project cask and, 2) the degradation mechanisms that could change gas compositions culminates in an adaptive gas sampling frequency strategy. This adaptive strategy is compared against the sampling frequency that has been developed based on operational considerations.

  13. Analysis of the effect of UO{sub 2} high burnup microstructure on fission gas release

    Energy Technology Data Exchange (ETDEWEB)

    Jernkvist, Lars Olof; Massih, Ali [Quantum Technologies AB, Uppsala Science Park (Sweden)

    2002-10-01

    This report deals with high-burnup phenomena with relevance to fission gas release from UO{sub 2} nuclear fuel. In particular, we study how the fission gas release is affected by local buildup of fissile plutonium isotopes and fission products at the fuel pellet periphery, with subsequent formation of a characteristic high-burnup rim zone micro-structure. An important aspect of these high-burnup effects is the degradation of fuel thermal conductivity, for which prevalent models are analysed and compared with respect to their theoretical bases and supporting experimental data. Moreover, the Halden IFA-429/519.9 high-burnup experiment is analysed by use of the FRAPCON3 computer code, into which modified and extended models for fission gas release are introduced. These models account for the change in Xe/Kr-ratio of produced and released fission gas with respect to time and space. In addition, several alternative correlations for fuel thermal conductivity are implemented, and their impact on calculated fission gas release is studied. The calculated fission gas release fraction in IFA-429/519.9 strongly depends on what correlation is used for the fuel thermal conductivity, since thermal release dominates over athermal release in this particular experiment. The conducted calculations show that athermal release processes account for less than 10% of the total gas release. However, athermal release from the fuel pellet rim zone is presumably underestimated by our models. This conclusion is corroborated by comparisons between measured and calculated Xe/Kr-ratios of the released fission gas.

  14. Advanced Corrosion-Resistant Zr Alloys for High Burnup and Generation IV Applications

    Energy Technology Data Exchange (ETDEWEB)

    Arthur Motta; Yong Hwan Jeong; R.J. Comstock; G.S. Was; Y.S. Kim

    2006-10-31

    The objective of this collaboration between four institutions in the US and Korea is to demonstrate a technical basis for the improvement of the corrosion resistance of zirconium-based alloys in more extreme operating environments (such as those present in severe fuel duty,cycles (high burnup, boiling, aggressive chemistry) andto investigate the feasibility (from the point of view of corrosion rate) of using advanced zirconium-based alloys in a supercritical water environment.

  15. EPRI/DOE High Burnup Fuel Sister Pin Test Plan Simplification and Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Saltzstein, Sylvia J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sorenson, Ken B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Hanson, Brady [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Billone, Mike [Argonne National Lab. (ANL), Argonne, IL (United States); Scaglione, John [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Rose [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bevard, Bruce [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    The EPRI/DOE High Burnup Confirmatory Data Project (herein called the "Demo") is a multi-year, multi-entity confirmation demonstration test with the purpose of providing quantitative and qualitative data to show how high-burnup fuel ages in dry storage over a ten-year period. The Demo involves obtaining 32 assemblies of high-burnup PWR fuel of four common cladding alloys from the North Anna Nuclear Power Plant, drying them according to standard plant procedures, and then storing them in an NRC-licensed TN-3 2B cask on the North Anna dry storage pad for ten years. After the ten-year storage time, the cask will be opened and the rods will be examined for signs of aging. Twenty-five rods from assemblies of similar claddings, in-reactor placement, and burnup histories (herein called "sister rods") have been shipped from the North Anna Nuclear Power Plant and are currently being nondestructively tested at Oak Ridge National Laboratory. After the non-destructive testing has been completed for each of the twenty-five rods, destructive analysis will be performed at ORNL, PNNL, and ANL to obtain mechanical data. Opinions gathered from the expert interviews, ORNL and PNNL Sister Rod Test Plans, and numerous meetings has resulted in the Simplified Test Plan described in this document. Some of the opinions and discussions leading to the simplified test plan are included here. Detailed descriptions and background are in the ORNL and PNNL plans in the appendices . After the testing described in this simplified test plan h as been completed , the community will review all the collected data and determine if additional testing is needed.

  16. Analysis of simulated high burnup nuclear fuel by laser induced breakdown spectroscopy

    Science.gov (United States)

    Singh, Manjeet; Sarkar, Arnab; Banerjee, Joydipta; Bhagat, R. K.

    2017-06-01

    Advanced Heavy Water Reactor (AHWR) grade (Th-U)O2 fuel sample and Simulated High Burn-Up Nuclear Fuels (SIMFUEL) samples mimicking the 28 and 43 GWd/Te irradiated burn-up fuel were studied using laser-induced breakdown spectroscopy (LIBS) setup in a simulated hot-cell environment from a distance of > 1.5 m. Resolution of 60 emission lines of fission products was identified. Among them only a few emission lines were found to generate calibration curves. The study demonstrates the possibility to investigate impurities at concentrations around hundreds of ppm, rapidly at atmospheric pressure without any sample preparation. The results of Ba and Mo showed the advantage of LIBS analysis over traditional methods involving sample dissolution, which introduces possible elemental loss. Limits of detections (LOD) under Ar atmosphere shows significant improvement, which is shown to be due to the formation of stable plasma.

  17. Study on nuclear physics of high burn-up full MOX-BWR core

    Energy Technology Data Exchange (ETDEWEB)

    Shirakawa, Toshihisa; Okubo, Tsutomu; Ochiai, Masa-aki [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1998-08-01

    In this report, neutronics study of full Mixed-oxide (MOX) high burn-up BWR core is presented. Our design goals are about 3-year cycle length, four-batch refueling scheme and more than 100GWd/t fuel discharge burn-up. Base core configuration is 1,350MWe US version of ABWR with 9 x 9 type fuel assembly. Investigation of the reactor core has been carried out by arranging Gd{sub 2}O{sub 3} contents in fuel rods and changing water to fuel volume ratio (V{sub m}/V{sub f}) through the number of water rods or adjustment of fuel clad diameter. JAERI`s general purpose neutronics code system SRAC95 was used for two dimensional XY fuel assembly cell neutronics calculations. Calculated cases are for a comparatively high moderated fuel assembly with 9 water rods, a fuel assembly without water rods and a comparatively low moderated fuel assembly without water rods and with larger fuel clad diameter. All these 3 cases seem to achieve our design goals mentioned above. For the last case, three dimensional core burn-up calculation was performed by this code system. This case seems to attain a low linear power density and the operation with all control rod out. (author)

  18. High burnup performance of Mg, Mg-Nb and Ti doped UO{sub 2} fuels

    Energy Technology Data Exchange (ETDEWEB)

    Shiratori, Tetsuo; Serizawa, Hiroyuki; Fukuda, Kousaku [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Fujino, Takeo; Sato, Nobuaki; Yamada, Kohta [Institute for Advanced Materials Processing, Tohoku Univ., Sendai, Miyagi (Japan)

    2000-09-01

    In order to control irradiation performance of fuel swelling and FP gas release etc. at high burnups of light water reactor fuels, doped UO{sub 2} pellet fuels were prepared and their irradiation behavior was examined. The UO{sub 2} pellets doped 2.5 to 15mol%Mg, 5mol%Mg - 5mol%Nb, and 3.5mol%Ti and undoped UO{sub 2} pellets as a reference fuel were loaded together in a capsule and irradiated to the maximum burnups of 94GWd/t(U) below temperature of 1000degC in the JRR-3M reactor of JAERI. As results of post-irradiation examinations such as visual inspection, dimensional and density change measurements, thermal diffusivity and ceramography with optical microscope and EPMA, no difference was observed between the doped and the reference UO{sub 2} fuels. And valuable results were obtained on high burnup properties for swelling rates, thermal conductivities, structure changes and so on. (author)

  19. Investigation of very high burnup UO{sub 2} fuels in Light Water Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, Fabiola

    2017-03-27

    Historically, the average discharge burnup of Light Water Reactor (LWR) fuel has increased almost continuously. On one side, increase in the average discharge burnup is attractive because it contributes to decrease part of the fuel cycle costs. On the other side, it raises the practical problem of predicting the performance, longevity and properties of reactor fuel elements upon accumulation of irradiation damage and fission products both during in-reactor operation and after discharge. Performance of the fuel and structural components of the core is one of the critical areas on which the economic viability and public acceptance of nuclear energy production hinges. Along the pellet radius, the fuel matrix is subjected to extremely heterogeneous alteration and damage, as a result of temperature and burnup gradients. In particular, in the peripheral region of LWR UO{sub 2} fuel pellets, when the local burnup exceeds 50-70 GWd/tHM, a microstructural transformation starts to take place, as a consequence of enhanced accumulation of radiation damage, fission products and limited thermal recovery. The newly formed structure is commonly named High Burnup Structure (HBS). The HBS is characterised by three main features: (a) formation of submicrometric grains from the original grains, (b) depletion of fission gas from the fuel matrix, (c) steep increase in the porosity, which retains most of the gas depleted from the fuel matrix. The last two aspects rose significant attention because of the important impact of the fission gas behaviour on integral fuel performance. The porosity increase controls the gas-driven swelling, worsening the cladding loading once the fuel-cladding gap is closed. Another concern is that the large retention of fission gas within the HBS could lead to significant release at high burnups through the degradation of thermal conductivity or contribute to fuel pulverisation during accidental conditions. Need of more experimental investigations about the

  20. Analysis of Experimental Data for High Burnup PWR Spent Fuel Isotopic Validation - Vandellos II Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ilas, Germina [ORNL; Gauld, Ian C [ORNL

    2011-01-01

    This report is one of the several recent NUREG/CR reports documenting benchmark-quality radiochemical assay data and the use of the data to validate computer code predictions of isotopic composition for spent nuclear fuel, to establish the uncertainty and bias associated with code predictions. The experimental data analyzed in the current report were acquired from a high-burnup fuel program coordinated by Spanish organizations. The measurements included extensive actinide and fission product data of importance to spent fuel safety applications, including burnup credit, decay heat, and radiation source terms. Six unique spent fuel samples from three uranium oxide fuel rods were analyzed. The fuel rods had a 4.5 wt % {sup 235}U initial enrichment and were irradiated in the Vandellos II pressurized water reactor operated in Spain. The burnups of the fuel samples range from 42 to 78 GWd/MTU. The measurements were used to validate the two-dimensional depletion sequence TRITON in the SCALE computer code system.

  1. Effects of Lower Drying-Storage Temperature on the Ductility of High-Burnup PWR Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Billone, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Burtseva, T. A. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-08-30

    The purpose of this research effort is to determine the effects of canister and/or cask drying and storage on radial hydride precipitation in, and potential embrittlement of, high-burnup (HBU) pressurized water reactor (PWR) cladding alloys during cooling for a range of peak drying-storage temperatures (PCT) and hoop stresses. Extensive precipitation of radial hydrides could lower the failure hoop stresses and strains, relative to limits established for as-irradiated cladding from discharged fuel rods stored in pools, at temperatures below the ductile-to-brittle transition temperature (DBTT).

  2. Microhardness and Young's modulus of high burn-up UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, F. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Technische Universität München, Faculty of Mechanical Engineering, Department of Nuclear Engineering, D-85748, Garching bei München (Germany); Pizzocri, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Politecnico di Milano, Department of Energy, Nuclear Engineering Division, 20156, Milano (Italy); Marchetti, M. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Université Montpellier 2, Institut d’Electronique du Sud UMR CNRS 5214, 34095, Montpellier (France); Schubert, A.; Van Uffelen, P. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Luzzi, L. [Politecnico di Milano, Department of Energy, Nuclear Engineering Division, 20156, Milano (Italy); Papaioannou, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany); Macián-Juan, R. [Technische Universität München, Faculty of Mechanical Engineering, Department of Nuclear Engineering, D-85748, Garching bei München (Germany); Rondinella, V.V., E-mail: Vincenzo.RONDINELLA@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125, Karlsruhe (Germany)

    2016-10-15

    Vickers microhardness (HV{sub 0.1}) and Young's modulus (E) measurements of LWR UO{sub 2} fuel at burn-up ≥60 GWd/tHM are presented. Their ratio HV{sub 0.1}/E was found constant in the range 60–110 GWd/tHM. From the ratio and the microhardness values vs porosity, the Young's modulus dependence on porosity was derived and extended to the full radial profile, including the high burn-up structure (HBS). The dependence is well represented by a linear correlation. The data were compared to fuel performance codes correlations. A burn-up dependent factor was introduced in the Young's modulus expression. The modifications extend the experimental validation range of the TRANSURANUS correlation from un-irradiated to irradiated UO{sub 2} and up to 20% porosity. First simulations of LWR fuel rod irradiations were performed in order to illustrate the impact on fuel performance. In the specific cases selected, the simulations suggest a limited effect of the Young's modulus decrease due to burn-up on integral fuel performance. - Highlights: • Vickers microhardness and Young's modulus data of high burnup fuels are presented. • The data are compared to fuel performance codes' correlations. • A burn-up dependent factor is introduced for the Young's modulus of irradiated fuel. • The modification extends ranges of experimental validation of the code correlation. • The new burn-up dependent factor has limited effect on integral fuel performance.

  3. Used Fuel Disposition Campaign - Baseline Studies for Ring Compression Testing of High-Burnup Fuel Cladding

    Energy Technology Data Exchange (ETDEWEB)

    Billone, M. C. [Argonne National Lab. (ANL), Argonne, IL (United States); Burtseva, T. A. [Argonne National Lab. (ANL), Argonne, IL (United States); Liu, Y. Y. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-11-23

    Structural analyses of high-burnup fuel require cladding mechanical properties and failure limits to assess fuel behavior during long-term dry cask storage and transportation. Pre-storage drying-transfer operations and early stage storage subject cladding to higher temperatures and much higher pressure-induced tensile hoop stresses relative to in-reactor operation and pool storage. Under these conditions, radial hydrides may precipitate during slow cooling and provide an additional embrittlement mechanism as the cladding temperature decreases below the ductile-to-brittle transition temperature (DBTT). On the basis of previous test results, susceptibility to radial-hydride precipitation depends on cladding material, microstructure, and pre-drying distribution of hydrides across the cladding wall, as well as peak hoop stresses and temperatures during drying operations and storage. Susceptibility to embrittlement depends on the extent of radial-hydride precipitation and the thickness of the outer-surface hydride rim. These results highlight the importance of determining the DBTT for high-burnup cladding as a function of peak drying-storage temperatures and stresses and including the relevant mechanical properties in cask structural analyses. Additional testing is needed at lower (and perhaps more realistic) peak drying-storage temperatures and stresses, for which the DBTT is expected to decrease.

  4. Designing Critical Experiments in Support of Full Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Roberts, Jeremy A [ORNL

    2008-01-01

    Burnup credit is the process of accounting for the negative reactivity due to fuel burnup and generation of parasitic absorbers over fuel assembly lifetime. For years, the fresh fuel assumption was used as a simple bound in criticality work for used fuel storage and transportation. More recently, major actinides have been included [1]. However, even this yields a highly conservative estimate in criticality calculations. Because of the numerous economical benefits including all available negative reactivity (i.e., full burnup credit) could provide [2], it is advantageous to work toward full burnup credit. Unfortunately, comparatively little work has been done to include non-major actinides and other fission products (FP) in burnup credit analyses due in part to insufficient experimental data for validation of codes and nuclear data. The Burnup Credit Criticality Experiment (BUCCX) at Sandia National Laboratory was a set of experiments with {sup 103}Rh that have relevance for burnup credit [3]. This work uses TSUNAMI-3D to investigate and adjust a BUCCX model to match isotope-specific, energy-dependent k{sub eff} sensitivity profiles to those of a representative high-capacity cask model (GBC-32) [4] for each FP of interest. The isotopes considered are {sup 149}Sm, {sup 143}Nd, {sup 103}Rh, {sup 133}Cs, {sup 155}Gd, {sup 152}Sm, {sup 99}Tc, {sup 145}Nd, {sup 153}Eu, {sup 147}Sm, {sup 109}Ag, {sup 95}Mo, {sup 150}Sm, {sup 101}Ru, and {sup 151}Eu. The goal is to understand the biases and bias uncertainties inherent in nuclear data, and ultimately, to apply these in support of full burnup credit.

  5. Fuel modeling at high burn-up: recent development of the GERMINAL code

    Science.gov (United States)

    Melis, J.-C.; Piron, J.-P.; Roche, L.

    1993-09-01

    In the frame of research and development on fast breeder reactors fuels, CEA/DEC is developing the computer code GERMINAL to study fuel pin thermal and mechanical behaviour during steady-state and accidental conditions. The development of the GERMINAL 1 code is foreseen in two steps: (1) The GERMINAL 1-1 version which is presently delivered fully documented with a physical qualification guaranteed up to 8 at%. (2) The GERMINAL 1-2 version which, in addition to what is presently treated in GERMINAL 1-1, includes the treatment of high burn-up effects on the the fission gas release and the fuel-clad interface (called JOG). The validation of GERMINAL 1-2 is presently in progress and will include specific experiments (JOG tests) performed in the CABRI reactor.

  6. Accident source terms for boiling water reactors with high burnup cores.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Leonard, Mark Thomas

    2007-11-01

    The primary objective of this report is to provide the technical basis for development of recommendations for updates to the NUREG-1465 Source Term for BWRs that will extend its applicability to accidents involving high burnup (HBU) cores. However, a secondary objective is to re-examine the fundamental characteristics of the prescription for fission product release to containment described by NUREG-1465. This secondary objective is motivated by an interest to understand the extent to which research into the release and behaviors of radionuclides under accident conditions has altered best-estimate calculations of the integral response of BWRs to severe core damage sequences and the resulting radiological source terms to containment. This report, therefore, documents specific results of fission product source term analyses that will form the basis for the HBU supplement to NUREG-1465. However, commentary is also provided on observed differences between the composite results of the source term calculations performed here and those reflected NUREG-1465 itself.

  7. Mechanical Fatigue Testing of High-Burnup Fuel for Transportation Applications

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Wang, Hong [ORNL

    2015-05-01

    This report describes testing designed to determine the ability of high burnup (HBU) (>45 GWd/MTU) spent fuel to maintain its integrity under normal conditions of transportation. An innovative system, Cyclic Integrated Reversible-bending Fatigue Tester (CIRFT), has been developed at Oak Ridge National Laboratory (ORNL) to test and evaluate the mechanical behavior of spent nuclear fuel (SNF) under conditions relevant to storage and transportation. The CIRFT system is composed of a U-frame equipped with load cells for imposing the pure bending loads on the SNF rod test specimen and measuring the in-situ curvature of the fuel rod during bending using a set up with three linear variable differential transformers (LVDTs).

  8. Advanced Corrosion-Resistant Zr Alloys for High Burnup and Generation IV Application

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Y. H.; Park, S. Y.; Lee, M. H.; Choi, B. K.; Baek, J. H.; Park, J. Y.; Kim, J. H.; Kim, H. G.; Jung, Y. H.; Bang, B. G

    2006-08-15

    The systematic study was performed to develop the advanced corrosion-resistant Zr alloys for high burnup and Gen IV application. The corrosion behavior was significantly changed with the alloy composition and the corrosion environment. In general, the model alloys with a higher alloying elements showed a higher corrosion resistance. Among the model alloys tested in this study, Zr-10Cr-0.2Fe showed the best corrosion resistance regardless of the corrosion condition. The oxide on the higher corrosion-resistant alloy such as Zr-1.0Cr-0.2Fe consisted of mainly columnar grains, and it have a higher tetragonal phase stability. In comparison with other alloys being considered for the SCWR, the Zr alloys showed a lower corrosion rate than ferritic-martensitic steels. The results of this study imply that, at least from a corrosion standpoint, Zr alloys deserve consideration as potential cladding or structural materials in supercritical water cooled reactors.

  9. The impact of interface bonding efficiency on high-burnup spent nuclear fuel dynamic performance

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Hao, E-mail: jiangh@ornl.gov; Wang, Jy-An John; Wang, Hong

    2016-12-01

    Highlights: • To investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on its dynamic performance. • Flexural rigidity, EI = M/κ, estimated from FEA results were benchmarked with SNF dynamic experimental results, and used to evaluate interface bonding efficiency. • Interface bonding efficiency can significantly dictate the SNF system rigidity and the associated dynamic performance. • With consideration of interface bonding efficiency and fuel cracking, HBU SNF fuel property was estimated with SNF static and dynamic experimental data. - Abstract: Finite element analysis (FEA) was used to investigate the impact of interfacial bonding efficiency at pellet-pellet and pellet-clad interfaces of high-burnup (HBU) spent nuclear fuel (SNF) on system dynamic performance. Bending moments M were applied to FEA model to evaluate the system responses. From bending curvature, κ, flexural rigidity EI can be estimated as EI = M/κ. The FEA simulation results were benchmarked with experimental results from cyclic integrated reversal bending fatigue test (CIRFT) of HBR fuel rods. The consequence of interface debonding between fuel pellets and cladding is a redistribution of the loads carried by the fuel pellets to the clad, which results in a reduction in composite rod system flexural rigidity. Therefore, the interface bonding efficiency at the pellet-pellet and pellet-clad interfaces can significantly dictate the SNF system dynamic performance. With the consideration of interface bonding efficiency, the HBU SNF fuel property was estimated with CIRFT test data.

  10. 78 FR 67348 - Invitation for Public Comment on Draft Test Plan for the High Burnup Dry Storage Cask Research...

    Science.gov (United States)

    2013-11-12

    ... Invitation for Public Comment on Draft Test Plan for the High Burnup Dry Storage Cask Research and Development Project (CDP) AGENCY: Fuel Cycle Technologies, Office of Nuclear Energy, Department of Energy... multiple entities while comments are resolved. Dated: November 5, 2013. Jay Jones, Office of Fuel Cycle...

  11. Applicability of the MCNP-ACAB system to inventory prediction in high-burnup fuels: sensitivity/uncertainty estimates

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Herranz, N.; Cabellos, O. [Madrid Polytechnic Univ., Dept. of Nuclear Engineering (Spain); Cabellos, O.; Sanz, J. [Madrid Polytechnic Univ., 2 Instituto de Fusion Nuclear (Spain); Sanz, J. [Univ. Nacional Educacion a Distancia, Dept. of Power Engineering, Madrid (Spain)

    2005-07-01

    We present a new code system which combines the Monte Carlo neutron transport code MCNP-4C and the inventory code ACAB as a suitable tool for high burnup calculations. Our main goal is to show that the system, by means of ACAB capabilities, enables us to assess the impact of neutron cross section uncertainties on the inventory and other inventory-related responses in high burnup applications. The potential impact of nuclear data uncertainties on some response parameters may be large, but only very few codes exist which can treat this effect. In fact, some of the most reported effective code systems in dealing with high burnup problems, such as CASMO-4, MCODE and MONTEBURNS, lack this capability. As first step, the potential of our system, ruling out the uncertainty capability, has been compared with that of those code systems, using a well referenced high burnup pin-cell benchmark exercise. It is proved that the inclusion of ACAB in the system allows to obtain results at least as reliable as those obtained using other inventory codes, such as ORIGEN2. Later on, the uncertainty analysis methodology implemented in ACAB, including both the sensitivity-uncertainty method and the uncertainty analysis by the Monte Carlo technique, is applied to this benchmark problem. We estimate the errors due to activation cross section uncertainties in the prediction of the isotopic content up to the high-burnup spent fuel regime. The most relevant uncertainties are remarked, and some of the most contributing cross sections to those uncertainties are identified. For instance, the most critical reaction for Am{sup 242m} is Am{sup 241}(n,{gamma}-m). At 100 MWd/kg, the cross-section uncertainty of this reaction induces an error of 6.63% on the Am{sup 242m} concentration.The uncertainties in the inventory of fission products reach up to 30%.

  12. Modeling of pore coarsening in the rim region of high burn-up UO{sub 2} fuel

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Hongxing; Long, Chong Sheng [Science and Technology on Reactor Fuel and Materials Laboratory, Nuclear Power Institute of China, Chengdu (China)

    2016-08-15

    An understanding of the coarsening process of the large fission gas pores in the high burn-up structure (HBS) of irradiated UO{sub 2} fuel is very necessary for analyzing the safety and reliability of fuel rods in a reactor. A numerical model for the description of pore coarsening in the HBS based on the Ostwald ripening mechanism, which has successfully explained the coarsening process of precipitates in solids is developed. In this model, the fission gas atoms are treated as the special precipitates in the irradiated UO{sub 2} fuel matrix. The calculated results indicate that the significant pore coarsening and mean pore density decrease in the HBS occur upon surpassing a local burn-up of 100 GWd/tM. The capability of this model is successfully validated against irradiation experiments of UO{sub 2} fuel, in which the average pore radius, pore density, and porosity are directly measured as functions of local burn-up. Comparisons with experimental data show that, when the local burn-up exceeds 100 GWd/tM, the calculated results agree well with the measured data.

  13. Critical assessment of the pore size distribution in the rim region of high burnup UO{sub 2} fuels

    Energy Technology Data Exchange (ETDEWEB)

    Cappia, F. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Department of Nuclear Engineering, Faculty of Mechanical Engineering, Technische Universität München, D-85748 Garching bei München (Germany); Pizzocri, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Nuclear Engineering Division, Energy Department, Politecnico di Milano, 20156 Milano (Italy); Schubert, A.; Van Uffelen, P.; Paperini, G.; Pellottiero, D. [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany); Macián-Juan, R. [Department of Nuclear Engineering, Faculty of Mechanical Engineering, Technische Universität München, D-85748 Garching bei München (Germany); Rondinella, V.V., E-mail: Vincenzo.RONDINELLA@ec.europa.eu [European Commission, Joint Research Centre, Institute for Transuranium Elements, P.O. Box 2340, 76125 Karlsruhe (Germany)

    2016-11-15

    A new methodology is introduced to analyse porosity data in the high burnup structure. Image analysis is coupled with the adaptive kernel density estimator to obtain a detailed characterisation of the pore size distribution, without a-priori assumption on the functional form of the distribution. Subsequently, stereological analysis is carried out. The method shows advantages compared to the classical approach based on the histogram in terms of detail in the description and accuracy within the experimental limits. Results are compared to the approximation of a log-normal distribution. In the investigated local burnup range (80–200 GWd/tHM), the agreement of the two approaches is satisfactory. From the obtained total pore density and mean pore diameter as a function of local burnup, pore coarsening is observed starting from ≈100 GWd/tHM, in agreement with a previous investigation. - Highlights: • A new methodology to analyse porosity is introduced. • The method shows advantages compared to the histogram. • Pore density and mean diameter data vs. burnup are presented. • Pore coarsening is observed starting from ≈100 GWd/tHM.

  14. TEM Characterization of High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Jian Gan; Brandon Miller; Dennis Keiser; Adam Robinson; James Madden; Pavel Medvedev; Daniel Wachs

    2014-04-01

    As an essential part of global nuclear non-proliferation effort, the RERTR program is developing low enriched U-Mo fuels (< 20% U-235) for use in research and test reactors that currently employ highly enriched uranium fuels. One type of fuel being developed is a dispersion fuel plate comprised of U-7Mo particles dispersed in Al alloy matrix. Recent TEM characterizations of the ATR irradiated U-7Mo dispersion fuel plates include the samples with a local fission densities of 4.5, 5.2, 5.6 and 6.3 E+21 fissions/cm3 and irradiation temperatures of 101-136?C. The development of the irradiated microstructure of the U-7Mo fuel particles consists of fission gas bubble superlattice, large gas bubbles, solid fission product precipitates and their association to the large gas bubbles, grain subdivision to tens or hundreds of nanometer size, collapse of bubble superlattice, and amorphisation. This presentation will describe the observed microstructures specifically focusing on the U-7Mo fuel particles. The impact of the observed microstructure on the fuel performance and the comparison of the relevant features with that of the high burn-up UO2 fuels will be discussed.

  15. SEM Characterization of the High Burn-up Microstructure of U-7Mo Alloy

    Energy Technology Data Exchange (ETDEWEB)

    Dennis D. Keiser, Jr.; Jan-Fong Jue; Jian Gan; Brandon Miller; Adam Robinson; Pavel Medvedev; James Madden; Dan Wachs; M. Teague

    2014-04-01

    During irradiation, the microstructure of U-7Mo evolves until at a fission density near 5x1021 f/cm3 a high-burnup microstructure exists that is very different than what was observed at lower fission densities. This microstructure is dominated by randomly distributed, relatively large, homogeneous fission gas bubbles. The bubble superlattice has collapsed in many microstructural regions, and the fuel grain sizes, in many areas, become sub-micron in diameter with both amorphous fuel and crystalline fuel present. Solid fission product precipitates can be found inside the fission gas bubbles. To generate more information about the characteristics of the high-fission density microstructure, three samples irradiated in the RERTR-7 experiment have been characterized using a scanning electron microscope equipped with a focused ion beam. The FIB was used to generate samples for SEM imaging and to perform 3D reconstruction of the microstructure, which can be used to look for evidence of possible fission gas bubble interlinkage.

  16. High-Burnup-Structure (HBS): Model Development in MARMOT for HBS Formation and Stability Under Radiation and High Temperature

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bai, X. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Zhang, Y. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Biner, B. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    A detailed phase field model for the formation of High Burnup Structure (HBS) was developed and implemented in MARMOT. The model treats the HBS formation as an irradiation-induced recrystallization. The model takes into consideration the stored energy associated with dislocations formed under irradiation. The accumulation of radiation damage, hence, increases the system free energy and triggers recrystallization. The increase in the free energy due to the formation of new grain boundaries is offset by the reduction in the free energy by creating dislocation-free grains at the expense of the deformed grains. The model was first used to study the growth of recrystallized flat and circular grains. The model reults were shown to agree well with theorrtical predictions. The case of HBS formation in UO2 was then investigated. It was found that a threshold dislocation density of (or equivalently a threshold burn-up of 33-40 GWd/t) is required for HBS formation at 1200K, which is in good agrrement with theory and experiments. In future studies, the presence of gas bubbles and their effect on the formation and evolution of HBS will be considered.

  17. Thermal property change of MOX and UO{sub 2} irradiated up to high burnup of 74 GWd/t

    Energy Technology Data Exchange (ETDEWEB)

    Nakae, Nobuo, E-mail: nakae-nobuo@jnes.go.jp [Japan Nuclear Energy Safety Organization (JNES), Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Akiyama, Hidetoshi; Miura, Hiromichi; Baba, Toshikazu; Kamimura, Katsuichiro [Japan Nuclear Energy Safety Organization (JNES), Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Kurematsu, Shigeru; Kosaka, Yuji [Nuclear Development Corporation (NDC), 622-12, Funaishikawa, Tokai-mura, Ibaraki 319-1111 (Japan); Yoshino, Aya; Kitagawa, Takaaki [Mitsubishi Nuclear Fuel Co., LTD. (MNF), 12-1, Yurakucho 1-Chome, Chiyoda-ku, Tokyo 100-0006 (Japan)

    2013-09-15

    Thermal property is important because it controls fuel behavior under irradiation. The thermal property change at high burnup of more than 70 GWd/t is examined. Two kinds of MOX fuel rods, which were fabricated by MIMAS and SBR methods, and one referenced UO{sub 2} fuel rod were used in the experiment. These rods were taken from the pre-irradiated rods (IFA 609/626, of which irradiation test were carried out by Japanese PWR group) and re-fabricated and re-irradiated in HBWR as IFA 702 by JNES. The specification of fuel corresponds to that of 17 × 17 PWR type fuel and the axially averaged linear heat rates (LHR) of MOX rods are 25 kW/m (BOL of IFA 702) and 20 kW/m (EOL of IFA 702). The axial peak burnups achieved are about 74 GWd/t for both of MOX and UO{sub 2}. Centerline temperature and plenum gas pressure were measured in situ during irradiation. The measured centerline temperature is plotted against LHR at the position where thermocouples are fixed. The slopes of MOX are corresponded to each other, but that of UO{sub 2} is higher than those of MOX. This implies that the thermal conductivity of MOX is higher than that of UO{sub 2} at high burnup under the condition that the pellet–cladding gap is closed during irradiation. Gap closure is confirmed by the metallography of the postirradiation examinations. It is understood that thermal conductivity of MOX is lower than that of UO{sub 2} before irradiation since phonon scattering with plutonium in MOX becomes remarkable. A phonon scattering with plutonium decreases in MOX when burnup proceeds. Thus, thermal conductivity of MOX becomes close to that of UO{sub 2}. A reverse phenomenon is observed at high burnup region. The phonon scattering with fission products such as Nd and Zr causes a degradation of thermal conductivity of burnt fuel. It might be speculated that this scattering effect causes the phenomenon and the mechanism is discussed here.

  18. FY14 Status Report: CIRFT Testing Results on High Burnup UNF

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jy-An John [ORNL; Wang, Hong [ORNL; Jiang, Hao [ORNL

    2014-09-01

    The objective of this project is to perform a systematic study of SNF/UNF (spent nuclear fuel/or used nuclear fuel) integrity under simulated transportation environments by using hot cell testing technology developed recently at Oak Ridge National Laboratory (ORNL), CIRFT (Cyclic Integrated Reversible-Bending Fatigue Tester). Under Nuclear Regulatory Commission (NRC) sponsorship, ORNL completed four benchmarking tests, four static tests, and twelve dynamic or cycle tests on H. B. Robinson (HBR) high burn-up (HBU) fuel. With support from the US Department of Energy and the NRC, CIRFT testing has been continued. The CIRFT testing was conducted on three HBR rods (R3, R4, and R5), with two specimens failed and one specimen un-failed. The total number of cycles in the test of un-failed specimens went over 2.23 107; the test was stopped as because the specimen did not show any sign of failure. The data analysis on all the HBR SNF rods demonstrated that it is necessary to characterize the fatigue life of used fuel rods in terms of both the curvature amplitude and the maximum of absolute of curvature extremes. The latter is significant because the maxima of extremes signify the maximum of tensile stress of the outer fiber of the bending rod. So far, a large variety of hydrogen contents has been covered in the CIRFT testing on HBR rods. It has been shown that the load amplitude is the dominant factor that controls the lifetime of bending rods, but the hydrogen content also has an important effect on the lifetime attained, according to the load range tested.

  19. High burnup fuel onset conditions in dry storage. Prediction of EOL rod internal pressure

    Energy Technology Data Exchange (ETDEWEB)

    Feria, F.; Herranz, L.E.

    2015-07-01

    During dry storage, cladding resistance to failure can be affected by several degrading mechanisms like creep or hydrides radial reorientation. The driving force of these effects is the stress at which the cladding is submitted. The maximum stress in the cladding is determined by the end-of-reactor-life (EOL) rod internal pressure, PEOL, at the maximum temperature attained during dry storage. Thus, PEOL sets the initial conditions of storage for potential time-dependent changes in the cladding. Based on FRAPCON-3.5 calculations, the aim of this work is to analyse the PEOL of a PWR fuel rod irradiated to burnups greater than 60 GWd/tU, where limited information is available. In order to be conservative, demanding irradiation histories have been used with a peak linear power of 44 kW/m. FRAPCON-3.5 results show an increasing exponential trend of PEOL with burnup, from which a simple correlation has been derived. The comparison with experimental data found in the literature confirms the enveloping nature of the predicted curve. Based on that, a conservative prediction of cladding stress in dry storage has been obtained. The comparison with a critical stress threshold related to hydrides embrittlement seems to point out that this issue should not be a concern at burnups below 65 GWd/tU. (Author)

  20. Accident source terms for pressurized water reactors with high-burnup cores calculated using MELCOR 1.8.5.

    Energy Technology Data Exchange (ETDEWEB)

    Gauntt, Randall O.; Powers, Dana Auburn; Ashbaugh, Scott G.; Leonard, Mark Thomas; Longmire, Pamela

    2010-04-01

    In this study, risk-significant pressurized-water reactor severe accident sequences are examined using MELCOR 1.8.5 to explore the range of fission product releases to the reactor containment building. Advances in the understanding of fission product release and transport behavior and severe accident progression are used to render best estimate analyses of selected accident sequences. Particular emphasis is placed on estimating the effects of high fuel burnup in contrast with low burnup on fission product releases to the containment. Supporting this emphasis, recent data available on fission product release from high-burnup (HBU) fuel from the French VERCOR project are used in this study. The results of these analyses are treated as samples from a population of accident sequences in order to employ approximate order statistics characterization of the results. These trends and tendencies are then compared to the NUREG-1465 alternative source term prescription used today for regulatory applications. In general, greater differences are observed between the state-of-the-art calculations for either HBU or low-burnup (LBU) fuel and the NUREG-1465 containment release fractions than exist between HBU and LBU release fractions. Current analyses suggest that retention of fission products within the vessel and the reactor coolant system (RCS) are greater than contemplated in the NUREG-1465 prescription, and that, overall, release fractions to the containment are therefore lower across the board in the present analyses than suggested in NUREG-1465. The decreased volatility of Cs2MoO4 compared to CsI or CsOH increases the predicted RCS retention of cesium, and as a result, cesium and iodine do not follow identical behaviors with respect to distribution among vessel, RCS, and containment. With respect to the regulatory alternative source term, greater differences are observed between the NUREG-1465 prescription and both HBU and LBU predictions than exist between HBU and LBU

  1. Accident source terms for light-water nuclear power plants using high-burnup or MOX fuel.

    Energy Technology Data Exchange (ETDEWEB)

    Salay, Michael (U.S. Nuclear Regulatory Commission, Washington, D.C.); Gauntt, Randall O.; Lee, Richard Y. (U.S. Nuclear Regulatory Commission, Washington, D.C.); Powers, Dana Auburn; Leonard, Mark Thomas

    2011-01-01

    Representative accident source terms patterned after the NUREG-1465 Source Term have been developed for high burnup fuel in BWRs and PWRs and for MOX fuel in a PWR with an ice-condenser containment. These source terms have been derived using nonparametric order statistics to develop distributions for the timing of radionuclide release during four accident phases and for release fractions of nine chemical classes of radionuclides as calculated with the MELCOR 1.8.5 accident analysis computer code. The accident phases are those defined in the NUREG-1465 Source Term - gap release, in-vessel release, ex-vessel release, and late in-vessel release. Important differences among the accident source terms derived here and the NUREG-1465 Source Term are not attributable to either fuel burnup or use of MOX fuel. Rather, differences among the source terms are due predominantly to improved understanding of the physics of core meltdown accidents. Heat losses from the degrading reactor core prolong the process of in-vessel release of radionuclides. Improved understanding of the chemistries of tellurium and cesium under reactor accidents changes the predicted behavior characteristics of these radioactive elements relative to what was assumed in the derivation of the NUREG-1465 Source Term. An additional radionuclide chemical class has been defined to account for release of cesium as cesium molybdate which enhances molybdenum release relative to other metallic fission products.

  2. Instant release of fission products in leaching experiments with high burn-up nuclear fuels in the framework of the Euratom project FIRST- Nuclides

    Science.gov (United States)

    Lemmens, K.; González-Robles, E.; Kienzler, B.; Curti, E.; Serrano-Purroy, D.; Sureda, R.; Martínez-Torrents, A.; Roth, O.; Slonszki, E.; Mennecart, T.; Günther-Leopold, I.; Hózer, Z.

    2017-02-01

    The instant release of fission products from high burn-up UO2 fuels and one MOX fuel was investigated by means of leach tests. The samples covered PWR and BWR fuels at average rod burn-up in the range of 45-63 GWd/tHM and included clad fuel segments, fuel segments with opened cladding, fuel fragments and fuel powder. The tests were performed with sodium chloride - bicarbonate solutions under oxidizing conditions and, for one test, in reducing Ar/H2 atmosphere. The iodine and cesium release could be partially explained by the differences in sample preparation, leading to different sizes and properties of the exposed surface areas. Iodine and cesium releases tend to correlate with FGR and linear power rating, but the scatter of the data is significant. Although the gap between the fuel and the cladding was closed in some high burn-up samples, fissures still provide possible preferential transport pathways.

  3. Hydrides reorientation investigation of high burn-up PWR fuel cladding

    Science.gov (United States)

    Valance, Stéphane; Bertsch, Johannes

    2015-09-01

    The direction of formation of hydride in fuel cladding tube is a major issue for the assessment of the cladding remaining ductility after service. This behavior is quite well known for fresh material, but few results exist for irradiated material. The reorientation behavior of a Zircaloy-4 fuel cladding (AREVA duplex DX-D4) at a burn-up of around 72 GWd t-1 is investigated here. The increase of the fraction of reoriented hydrides through repeated thermo-mechanical loading is inspected; as well, the possibility to recover a state with a minimized quantity of reoriented hydrides is tested using pure thermal loading cycles. The study is completed by a qualitative assessment of the hydrogen density in the duplex layer, where a dependence of the hydrides density on the hoop stress state is observed.

  4. Development of a method for xenon determination in the microstructure of high burn-up nuclear fuel[Dissertation 17527

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, M. I

    2008-07-01

    In nuclear fuel, in approximately one quarter of the fissions, one of the two formed fission products is gaseous. These are mainly the noble gases xenon and krypton with isotopes of xenon contributing up to 90% of the product gases. These noble fission gases do not combine with other species, and have a low solubility in the normally used uranium oxide matrix. They can be dissolved in the fuel matrix or precipitate in nanometer-sized bubbles within the fuel grain, in micrometer-sized bubbles at the grain boundaries, and a fraction also precipitates in fuel pores, coming from fuel fabrication. A fraction of the gas can also be released into the plenum of the fuel rod. With increasing fission, and therefore burn-up, the ceramic fuel material experiences a transformation of its structure in the 'cooler' rim region of the fuel. A subdivision occurs of the original fuel grains of few microns size into thousands of small grains of sub-micron sizes. Additionally, larger pores are formed, which also leads into an increasing porosity in the fuel rim, called high burn-up structure. In this structure, only a small fraction of the fission gas remains in the matrix, the major quantity is said to accumulate in these pores. Because of this accumulation, the knowledge of the quantities of gas within these pores is of major interest in consideration to burn-up, fuel performance and especially for safety issues. In case of design based accidents, i.e. rapidly increasing temperature transients, the behavior of the fuel has to be estimated. Various analytical techniques have been used to determine the Xe concentration in nuclear fuel samples. The capabilities of EPMA (Electron Probe Micro-Analyser) and SIMS (Secondary Ion Mass Spectrometry) have been studied and provided some qualitative information, which has been used for determining Xe-matrix concentrations. First approaches combining these two techniques to estimate pore pressures have been recently reported. However

  5. Analysis of Corrosion Residues Collected from the Aluminum Basket Rails of the High-Burnup Demonstration Cask.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-03-01

    On September, 2015, an inspection was performed on the TN-32B cask that will be used for the high-burnup demonstration project. During the survey, wooden cribbing that had been placed within the cask eleven years earlier to prevent shifting of the basket during transport was removed, revealing two areas of residue on the aluminum basket rails, where they had contacted the cribbing. The residue appeared to be a corrosion product, and concerns were raised that similar attack could exist at more difficult-to-inspect locations in the canister. Accordingly, when the canister was reopened, samples of the residue were collected for analysis. This report presents the results of that assessment, which determined that the corrosion was due to the presence of the cribbing. The corrosion was associated with fungal material, and fungal activity likely contributed to an aggressive chemical environment. Once the cask has been cleaned, there will be no risk of further corrosion.

  6. French investigations of high burnup effect on LOCA thermomechanical behavior: Part 1. Experimental programmes in support of LOCA design methodologies

    Energy Technology Data Exchange (ETDEWEB)

    Waeckel, N. [EDF/SEPTEN Villeurbanne (France); GrandJean, C. [IPSN, Cadarache (France); Cauvin, R.; Lebuffe, C. [EDF/SCMI, Chinon (France)

    1997-01-01

    Within the framework of Burn-Up extension request, EDF, FRAMATOME, CEA and IPSN have carried out experimental programmes in order to provide the design of fuel rods under LOCA conditions with relevant data. The design methods used in France for LOCA are based on standard Appendix K methodology updated to take into account some penalties related to the actual conditions of the Nuclear Power Plant. Best-Estimate assessments are used as well. Experimental programmes concern plastic deformation and burst behavior of advanced claddings (EDGAR) and thermal shock quenching behavior of highly irradiated claddings (TAGCIR). The former reveals the important role played by the {alpha}/{beta} transformation kinetics related to advanced alloys (Niobium alloys) and the latter the significative impact of hydrogen charged during in-reactor corrosion on oxidation kinetics and failure behavior in terms of cooling rates.

  7. Corrosion studies with high burnup light water reactor fuel. Release of nuclides into simulated groundwater during accumulated contact time of up to two years

    Energy Technology Data Exchange (ETDEWEB)

    Zwicky, Hans-Urs (Zwicky Consulting GmbH, Remigen (Switzerland)); Low, Jeanett; Ekeroth, Ella (Studsvik Nuclear AB, Nykoeping (Sweden))

    2011-03-15

    In the framework of comprehensive research work supporting the development of a Swedish concept for the disposal of highly radioactive waste and spent fuel, Studsvik has performed a significant number of spent fuel corrosion studies under a variety of different conditions. These experiments, performed between 1990 and 2002, covered a burnup range from 27 to 49 MWd/kgU, which was typical for fuel to be disposed at that time. As part of this work, the so called Series 11 tests were performed under oxidising conditions in synthetic groundwater with fuel samples from a rod irradiated in the Ringhals 1 Boiling Water Reactor (BWR). In the meantime, Swedish utilities tend to increase the discharge burnup of fuel operated in their reactors. This means that knowledge of spent fuel corrosion performance has to be extended to higher burnup as well. Therefore, a series of experiments has been started at Studsvik, aiming at extending the data base acquired in the Series 11 corrosion tests to higher burnup fuel. Fuel burnup leads to complex and significant changes in the composition and properties of the fuel. The transformed microstructure, which is referred to as the high burnup structure or rim structure in the outer region of the fuel, consists of small grains of submicron size and a high concentration of pores of typical diameter 1 to 2 mum. This structure forms in UO{sub 2} fuel at a local burnup above 50 MWd/kgU, as long as the temperature is below 1,000-1,100 deg C. The high burnup at the pellet periphery is the consequence of plutonium build-up by neutron capture in 238U followed by fission of the formed plutonium. The amount of fission products in the fuel increases more or less linearly with burnup, in contrast to alpha emitting actinides that increase above average. As burnup across a spent fuel pellet is not uniform, but increases towards the periphery, the radiation field is also larger at the pellet surface. At the same time, it is easier for water to access the

  8. Relationship between changes in the crystal lattice strain and thermal conductivity of high burnup UO{sub 2} pellets

    Energy Technology Data Exchange (ETDEWEB)

    Amaya, Masaki, E-mail: amaya.masaki@jaea.go.j [Fuel Safety Research Group, Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Nakamura, Jinichi; Fuketa, Toyoshi [Fuel Safety Research Group, Nuclear Safety Research Center, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki 319-1195 (Japan); Kosaka, Yuji [Nuclear Development Corporation, 622-12, Funaishikawa, Tokai-mura, Naka-gun, Ibaraki 319-1111 (Japan)

    2010-01-01

    Two kinds of disk-shaped UO{sub 2} samples (4 mm in diameter and 1 mm in thickness) were irradiated in a test reactor up to about 60 and 130 GWd/t, respectively. The microstructures of the samples were investigated by means of optical microscopy, scanning electron microscopy/ electron probe micro-analysis (SEM/EPMA) and micro-X-ray diffractometry. The measured lattice parameters tended to be considerably smaller than the reported values, and the typical cauliflower structure which is often observed in high burnup fuel pellet is hardly seen in these samples. Thermal diffusivities of the samples were also measured by using a laser flash method, and their thermal conductivities were evaluated by multiplying the heat capacity of unirradiated UO{sub 2} and sample densities. While the thermal conductivities of sample 2 showed recovery after being annealed at 1500 K, those of sample 4 were not clearly observed even after being annealed at 1500 K. These trends suggest that the amount of accumulated irradiation-induced defects depends on the irradiation condition of each sample. From the comparison of the changes in the lattice parameter and strain energy density before and after the thermal diffusivity measurements, it is likely that the thermal conductivity recovery in the temperature region from 1200 to 1500 K is related to the migration of dislocation.

  9. Rapid aqueous release of fission products from high burn-up LWR fuel: Experimental results and correlations with fission gas release

    Science.gov (United States)

    Johnson, L.; Günther-Leopold, I.; Kobler Waldis, J.; Linder, H. P.; Low, J.; Cui, D.; Ekeroth, E.; Spahiu, K.; Evins, L. Z.

    2012-01-01

    Studies of the rapid aqueous release of fission products from UO 2 and MOX fuel are of interest for the assessment of the safety of geological disposal of spent fuel, because of the associated potential contribution to dose in radiological safety assessment. Studies have shown that correlations between fission gas release (FGR) and the fraction rapidly leached of various long-lived fission products can provide a useful method to obtain some of this information. Previously, these studies have been limited largely to fuel with burn-up values below 50 MWd/kg U. Collaborative studies involving SKB, Studsvik, Nagra and PSI have provided new data on short-term release of 137Cs and 129I for a number of fuels irradiated to burn-ups of 50-75 MWd/kgU. In addition a method for analysis of leaching solutions for 79Se was developed. The results of the studies show that the fractional release of 137Cs is usually much lower than the FGR covering the entire range of burn-ups studied. Fractional 129I releases are somewhat larger, but only in cases in which the fuel was forcibly extracted from the cladding. Despite the expected high degree of segregation of fission gas (and by association 137Cs and 129I) in the high burn-up rim, no evidence was found for a significant contribution to release from the rim region. The method for 79Se analysis developed did not permit its detection. Nonetheless, based on the detection limit, the results suggest that 79Se is not preferentially leached from spent fuel.

  10. Isotopic analyses and calculation by use of JENDL-3.2 for high burn-up UO{sub 2} and MOX spent fuels

    Energy Technology Data Exchange (ETDEWEB)

    Sasahara, Akihiro; Matsumura, Tetsuo [Central Research Inst. of Electric Power Industry, Komae, Tokyo (Japan). Komae Research Lab.; Nicolaou, G.; Betti, M.; Walker, C.T.

    1997-03-01

    The post irradiation examinations (PIE) were carried out for high burn-up UO{sub 2} spent fuel (3.8%U235, average burn-up:60GWd/t) and mixed oxide (MOX) spent fuel (5.07%Pu, average burn-up:45GWd/t). The PIE includes, (a) isotopic analysis, (b) electron probe microanalysis (EPMA) in pellet cross section and so on. The results of isotopic analyses and EPMA were compared with ORIGEN2/82 and VIM-BURN calculation results. In VIM-BURN calculation, the nuclear data of actinides were proceeded from new data file, JENDL-3.2. The sensitivities of power history and moderator density to nuclides composition were investigated by VIM-BURN calculation and consequently power history mainly effected on Am241 and Am242m and moderator density effected on fissile nuclides. From EPMA results of U and Pu distribution in pellet, VIM-BURN calculation showed reasonable distribution in pellet cross section. (author)

  11. Evaluation of the elastic constants of the high burnup nuclear fuel (U{sub 1-y},Gd{sub y})O{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Luciana T.; Dias, Marcio S., E-mail: ltl@cdtn.b, E-mail: marciod@cdtn.b [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2011-07-01

    Nuclear fuels with burnable poisons are applications in the scope of the nuclear energy for electricity generation. The discharge burnups of this type of fuel are higher than the discharge burnups of pure UO{sub 2} fuels with same enrichment of the fissile element. In conditions of high burnups and moderate transients, the fuel rods can be subject to the pellet/cladding mechanical interactions (PCMI). Elastic constants of the fuel and cladding are used in the thermo-mechanical evaluation of the PCMI. The fuel elastic constants are usually expressed as a function of temperature, composition and porosity. Data survey and modeling of elastic constants for the (U{sub 1-y},Gd{sub y})O{sub 2} fuel are developed in this paper. Due to small amount of the available measurements for the (U{sub 1-y},Gd{sub y})O{sub 2}, the modeling taken into account the data from UO{sub 2} and Gd{sub 2}O{sub 3} measurements. Available measurements of the Al{sub 2}O{sub 3} were also used in the model validation. The elastic constants of these materials have been fitted by an analytic equation, which depicts the whole range the dependences. (author)

  12. Separation of metallic residues from the dissolution of a high-burnup BWR fuel using nitrogen trifluoride

    Energy Technology Data Exchange (ETDEWEB)

    McNamara, Bruce K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buck, Edgar C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Soderquist, Chuck Z. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Smith, Frances N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mausolf, Edward J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Scheele, Randall D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-03-23

    Nitrogen trifluoride (NF3) was used to fluorinate the metallic residue from the dissolution of a high burnup, boiling water reactor fuel (~70 MWd/kgU). The metallic residue included the noble metal phase (containing ruthenium, rhodium, palladium, technetium, and molybdenum), and smaller amounts of zirconium, selenium, tellurium, and silver. Exposing the noble metal phase to 10% NF3 in argon between 400 and 550°C, removed molybdenum and technetium near 400°C as their volatile fluorides, and ruthenium near 500C as its volatile fluoride. The events were thermally and temporally distinct and the conditions specified are a recipe to separate these transition metals from each other and from the noble metal phase nonvolatile residue. Depletion of the volatile fluorides resulted in substantial exothermicity. Thermal excursion behavior was recorded under non-adiabatic, isothermal conditions that typically minimize heat release. Physical characterization of the metallic noble phase and its thermal behavior are consistent with high kinetic velocity reactions encouraged by the nanoparticulate phase or perhaps catalytic influences of the mixed platinum metals with nearly pure phase structure. Post-fluorination, only two phases were present in the residual nonvolatile fraction. These were identified as a nano-crystalline, metallic palladium cubic phase and a hexagonal rhodium trifluoride (RhF3) phase. The two phases were distinct as the sub-µm crystallites of metallic palladium were in contrast to the RhF3 phase, which grew from the parent nano-crystalline noble-metal phase during fluorination, to acicular crystals exceeding 20-µm in length.

  13. Technical Data to Justify Full Burnup Credit in Criticality Safety Licensing Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Enercon Services, Inc.

    2011-03-14

    ENERCON's understanding of the difficult issues related to obtaining and analyzing additional cross section test data to support Full Burnup Credit. A PIRT (Phenomena Identification and Ranking Table) analysis was performed by ENERCON to evaluate the costs and benefits of acquiring different types of nuclear data in support of Full Burnup Credit. A PIRT exercise is a formal expert elicitation process with the final output being the ranking tables. The PIRT analysis (Table 7-4: Results of PIRT Evaluation) showed that the acquisition of additional Actinide-Only experimental data, although beneficial, was associated with high cost and is not necessarily needed. The conclusion was that the existing Radiochemical Assay (RCA) data plus the French Haut Taux de Combustion (HTC)2 and handbook Laboratory Critical Experiment (LCE) data provide adequate benchmark validation for Actinide-Only Burnup Credit. The PIRT analysis indicated that the costs and schedule to obtain sufficient additional experimental data to support the addition of 16 fission products to Actinide-Only Burnup Credit to produce Full Burnup Credit are quite substantial. ENERCON estimates the cost to be $50M to $100M with a schedule of five or more years. The PIRT analysis highlights another option for fission product burnup credit, which is the application of computer-based uncertainty analyses (S/U - Sensitivity/Uncertainty methodologies), confirmed by the limited experimental data that is already available. S/U analyses essentially transform cross section uncertainty information contained in the cross section libraries into a reactivity bias and uncertainty. Recent work by ORNL and EPRI has shown that a methodology to support Full Burnup Credit is possible using a combination of traditional RCA and LCE validation plus S/U validation for fission product isotopics and cross sections. Further, the most recent cross section data (ENDF/B-VII) can be incorporated into the burnup credit codes at a reasonable cost

  14. Determination of Fission Gas Inclusion Pressures in High Burnup Nuclear Fuel using Laser Ablation ICP-MS combined with SEM/EPMA and Optical Microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Horvath, Matthias I.; Guenther-Leopold, Ines; Kivel, Niko; Restani, Renato [Laboratory for Materials Behavior, Nuclear Energy and Safety, Paul Scherrer Institut, Villigen, CH-5232 (Switzerland); Guillong, Marcel [Institute for Isotope Geology/Mineralogic Elements, ETH Zuerich, CH-8092 (Switzerland); Izmer, Andrei [Environmental and Resource Studies, Trent University, Peterborough, K9J 7B8 (Canada); Hellwig, Christian [Nuclear Technology Department, Nordostschweizerische Kraftwerke AG (NOK), Baden, CH-5401 (Switzerland); Guenther, Detlef [Laboratory for Inorganic Chemistry, Trace Elements and Microanalysis Group, ETH Zuerich, CH-8093 (Switzerland)

    2008-07-01

    In approximately 20% of all fissions at least one of the fission products is gaseous. These are mainly xenon and krypton isotopes contributing up to 90% by the xenon isotopes. Upon reaching a burn-up of 60 - 75 GWd/tHM a so called High Burnup Structure (HBS) is formed in the cooler rim of the fuel. In this region a depletion of the noble fission gases (FG) in the matrix and an enrichment of FG in {mu}m-sized pores can be observed. Recent calculations show that in these pores the pressure at room temperature can be as large as 30 MPa. The knowledge of the FG pressure in pores is important to understand the high burn-up fuel behavior under accident conditions (i.e. RIA or LOCA). With analytical methods routinely used for the characterization of solid samples, i.e. Electron Probe Micro Analysis (EPMA), Secondary Ion Mass Spectrometry (SIMS), the quantification of gaseous inclusions is very difficult to almost impossible. The combination of a laser ablation system (LA) with an inductively coupled plasma mass spectrometer (ICP-MS) offers a powerful tool for quantification of the gaseous pore inventory. This method offers the advantages of high spatial resolution with laser spot sizes down to 10 {mu}m and low detection limits. By coupling with scanning electron microscopy (SEM) for the pore size distribution, EPMA for the FG inventory in the fuel matrix and optical microscopy for the LA-crater sizes, the pressures in the pores and porosity was calculated. As a first application of this calibration technique for gases, measurements were performed on pressurized water reactor (PWR) fuel with a rod average of 105 GWd/tHM to determine the local FG pressure distribution. (authors)

  15. Conservative approach for PWR MOX Burnup Credit implementation

    Energy Technology Data Exchange (ETDEWEB)

    Jutier, Ludyvine; Checiak, Benoit; Raby, Jerome; Aguiar, Luis; Le Bars, Igor [IRSN, Fontenay-aux-Roses (France)

    2008-07-01

    Burnup Credit allows considering the reactivity decrease due to fuel irradiation in criticality studies for the nuclear fuel cycle. Its implementation requires to carefully analyze the validity of the assumption made to: define the axial profile of the burnup, determine the composition of the irradiated fuel and compute the criticality simulation. In the framework of Burnup Credit implementation for PWR mixed oxide fuels (MOX), this paper focus on the determination of a conservative inventory of the irradiated fuel. The studies presented in this paper concern: the influence of irradiation conditions and of the MOX fuel initial composition on the irradiated MOX fuel reactivity. Criticality calculations are also performed for PWR MOX fuel industrial applications in order to get Burnup Credit gain estimations. (authors)

  16. Effect of Control Blade History, and Axial Coolant Density and Burnup Profiles on BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, William BJ J [ORNL

    2016-01-01

    A technical basis for peak reactivity boiling water reactor (BWR) burnup credit (BUC) methods was recently generated, and the technical basis for extended BWR BUC is now being developed. In this paper, a number of effects related to extended BWR BUC are analyzed, including three major operational effects in BWRs: the coolant density axial distribution, the use of control blades during operation, and the axial burnup profile. Specifically, uniform axial moderator density profiles are analyzed and compared to previous results and an additional temporal fidelity study combing moderator density profiles for three different fuel assemblies is presented. Realistic control blade histories and cask criticality results are compared to previously generated constructed control blade histories. Finally, a preliminary study of the axial burnup profile is provided.

  17. Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

    Science.gov (United States)

    Ternovykh, Mikhail; Tikhomirov, Georgy; Saldikov, Ivan; Gerasimov, Alexander

    2017-09-01

    Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

  18. Decay heat power of spent nuclear fuel of power reactors with high burnup at long-term storage

    Directory of Open Access Journals (Sweden)

    Ternovykh Mikhail

    2017-01-01

    Full Text Available Decay heat power of actinides and fission products from spent nuclear fuel of power VVER-1000 type reactors at long-term storage is calculated. Two modes of storage are considered: mode in which single portion of actinides or fission products is loaded in storage facility, and mode in which actinides or fission products from spent fuel of one VVER reactor are added every year in storage facility during 30 years and then accumulated nuclides are stored without addition new nuclides. Two values of fuel burnup 40 and 70 MW·d/kg are considered for the mode of storage of single fuel unloading. For the mode of accumulation of spent fuel with subsequent storage, one value of burnup of 70 MW·d/kg is considered. Very long time of storage 105 years accepted in calculations allows to simulate final geological disposal of radioactive wastes. Heat power of fission products decreases quickly after 50-100 years of storage. The power of actinides decreases very slow. In passing from 40 to 70 MW·d/kg, power of actinides increases due to accumulation of higher fraction of 244Cm. These data are important in the back end of fuel cycle when improved cooling system of the storage facility will be required along with stronger radiation protection during storage, transportation and processing.

  19. Shutdown-induced tensile stress in monolithic miniplates as a possible cause of plate pillowing at very high burnup

    Energy Technology Data Exchange (ETDEWEB)

    Medvedev, Pavel G [Idaho National Laboratory; Ozaltun, Hakan [Idaho National Laboratory; Robinson, Adam Brady [Idaho National Laboratory; Rabin, Barry H [Idaho National Laboratory

    2014-04-01

    Post-irradiation examination of Reduced Enrichment for Research and Test Reactors (RERTR)-12 miniplates showed that in-reactor pillowing occurred in at least 4 plates, rendering performance of these plates unacceptable. To address in-reactor failures, efforts are underway to define the mechanisms responsible for in-reactor pillowing, and to suggest improvements to the fuel plate design and operational conditions. To achieve these objectives, the mechanical response of monolithic fuel to fission and thermally-induced stresses was modeled using a commercial finite element analysis code. Calculations of stresses and deformations in monolithic miniplates during irradiation and after the shutdown revealed that the tensile stress generated in the fuel increased from 2 MPa to 100 MPa at shutdown. The increase in tensile stress at shutdown possibly explains in-reactor pillowing of several RERTR-12 miniplates irradiated to the peak local burnup of up to 1.11x1022 fissions/cm3 . This paper presents the modeling approach and calculation results, and compares results with post-irradiation examinations and mechanical testing of irradiated fuel. The implications for the safe use of the monolithic fuel in research reactors are discussed, including the influence of fuel burnup and power on the magnitude of the shutdown-induced tensile stress.

  20. Effect of Control Blade History, and Axial Coolant Density and Burnup Profiles on BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [ORNL; Marshall, William BJ J [ORNL; Martinez-Gonzalez, Jesus S [ORNL

    2015-05-01

    Oak Ridge National Laboratory (ORNL) and the US Nuclear Regulatory Commission (NRC) have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling water reactor (BWR) fuel in storage and transportation systems (often referred to as casks) and spent fuel pools (SFPs). This work is divided into two main phases. The first phase investigated the applicability of peak reactivity methods currently used in SFPs to transportation and storage casks and the validation of reactivity calculations and spent fuel compositions within these methods. The second phase focuses on extending BUC beyond peak reactivity. This paper documents the analysis of the effects of control blade insertion history, and moderator density and burnup axial profiles for extended BWR BUC.

  1. SOURCE OF BURNUP VALUES FOR COMMERCIAL SPENT NUCLEAR FUEL ASSEMBLIES

    Energy Technology Data Exchange (ETDEWEB)

    BSC

    2004-12-01

    , initial {sup 235}U enrichment, and time of discharge from the reactor as well as the assigned burnup, but the distribution. of burnup axially along the assembly length is not provided. The axial burnup profile is maintained within acceptable bounds by the operating conditions of the nuclear reactor and is calculated during preparations to reload a reactor, but the actual burnup profile is not measured. The axial burnup profile is important to the determination of the reactivity of a waste package, so a conservative evaluation of the calculated axial profiles for a large database of SNF has been performed. The product of the axial profile evaluation is a profile that is conservative. Thus, there is no need for physical measurement of the axial profile. The assembly identifier is legible on each SNF assembly and the utility records provide the associated characteristics of the assembly. The conservative methodologies used to determine the criticality loading curve for a waste package provide sufficient margin so that criticality safety is assured for preclosure operations even in the event of a misload. Consideration of misload effects for postclosure time periods is provided by the criticality Features, Events, and Processes (FEPs) analysis. The conservative approaches used to develop and apply the criticality loading curve are thus sufficiently robust that the utility assigned burnup is an adequate source of burnup values, and additional means of verification of assigned burnup through physical measurements are not needed.

  2. PLUTON: Three-group neutronic code for burnup analysis of isotope generation and depletion in highly irradiated LWR fuel rods

    Energy Technology Data Exchange (ETDEWEB)

    Lemehov, Sergei E; Suzuki, Motoe [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2001-08-01

    PLUTON is a three-group neutronic code analyzing, as functions of time and burnup, the change of radial profiles, together with average values, of power density, burnup, concentration of trans-uranium elements, plutonium buildup, depletion of fissile elements, and fission product generation in water reactor fuel rod with standard UO{sub 2}, UO{sub 2}-Gd{sub 2}O{sub 3}, inhomogeneous MOX, and UO{sub 2}-ThO{sub 2}. The PLUTON code, which has been designed to be run on Windows PC, has adopted a theoretical shape function of neutron attenuation in pellet, which enables users to perform a very fast and accurate calculation easily. The present code includes the irradiation conditions of the Halden Reactor which gives verification data for the code. The total list of trans-uranium elements included in the calculations consists of {sub 92}U{sup 233-239}, {sub 93}Np{sup 237-239}, {sub 94}Pu{sup 238-243}, {sub 95}Am{sup 241-244} (including isomers), and {sub 96}Cm{sup 242-245}. Poisoning fission products are represented by {sub 54}Xe{sup 131,133,135}, {sub 48}Cd{sup 113}, {sub 62}Sm{sup 149,151,152}, {sub 64}Gd{sup 154-160}, {sub 63}Eu{sup 153,155}, {sub 36}Kr{sup 83,85}, {sub 42}Mo{sup 95}, {sub 43}Tc{sup 99}, {sub 45}Rh{sup 103}, {sub 47}Ag{sup 109}, {sub 53}I{sup 127,129,131}, {sub 55}Cs{sup 133}, {sub 57}La{sup 139}, {sub 59}Pr{sup 141}, {sub 60}Nd{sup 143-150}, {sub 61}Pm{sup 147}. Fission gases and volatiles included in the code are {sub 36}Kr{sup 83-86}, {sub 54}Xe{sup 129-136}, {sub 52}Te{sup 125-130}, {sub 53}I{sup 127-131}, {sub 55}Cs{sup 133-137}, and {sub 56}Ba{sup 135-140}. Verification has been performed up to 83 GWd/tU, and a satisfactory agreement has been obtained. (author)

  3. Preliminary Content Evaluation of the North Anna High Burn-Up Sister Fuel Rod Segments for Transportation in the 10-160B and NAC-LWT

    Energy Technology Data Exchange (ETDEWEB)

    Ketusky, E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2016-08-09

    The U.S. Department of Energy’s (DOE’s) Used Fuel Disposition Campaign (UFDC) Program has transported high-burnup nuclear sister fuel rods from a commercial nuclear power plant for purposes of evaluation and testing. The evaluation and testing of high-burnup used nuclear fuel is integral to DOE initiatives to collect information useful in determining the integrity of fuel cladding for future safe transportation of the fuel, and for determining the effects of aging, on the integrity of UNF subjected to extended storage and subsequent transportation. The UFDC Program, in collaboration with the U.S. Nuclear Regulatory Commission and the commercial nuclear industry, has obtained individual used nuclear fuel rods for testing. The rods have been received at Oak Ridge National Laboratory (ORNL) for both separate effects testing (SET) and small-scale testing (SST). To meet the research objectives, testing on multiple 6 inch fuel rod pins cut from the rods at ORNL will be performed at Pacific Northwest National Laboratory (PNNL). Up to 10 rod equivalents will be shipped. Options were evaluated for multiple shipments using the 10-160B (based on 4.5 rod equivalents) and a single shipment using the NAC-LWT. Based on the original INL/Virginia Power transfer agreement, the rods are assumed to 152 inches in length with a 0.374-inch diameter. This report provides a preliminary content evaluation for use of the 10-160B and NAC-LWT for transporting those fuel rod pins from ORNL to PNNL. This report documents the acceptability of using these packagings to transport the fuel segments from ORNL to PNNL based on the following evaluations: enrichment, A2 evaluation, Pu-239 FGE evaluation, heat load, shielding (both gamma and neutron), and content weight/structural evaluation.

  4. Simulations of highly reactive fluids

    Energy Technology Data Exchange (ETDEWEB)

    Fried, L E; Manaa, M R; Reed, E J

    2005-07-21

    We report density functional molecular dynamics simulations to determine the early chemical events of hot (T = 3000 K) and dense (1.97 g/cm{sup 3}, V/V{sub 0} = 0.68) nitromethane (CH{sub 3}NO{sub 2}). The first step in the decomposition process is an intermolecular proton abstraction mechanism that leads to the formation of CH{sub 3}NO{sub 2}H and the aci ion H{sub 2}CNO{sub 2}{sup -}, in support of evidence from static high-pressure and shock experiments. An intramolecular hydrogen transfer that transforms nitromethane into the aci acid form, CH{sub 2}NO{sub 2}H, accompanies this event. This is the first confirmation of chemical reactivity with bond selectivity for an energetic material near the condition of fully reacted specimen. We also report the decomposition mechanism followed up to the formation of H{sub 2}O as the first stable product.

  5. Fuel burnup measurements in FFTF

    Energy Technology Data Exchange (ETDEWEB)

    Rawlins, J.A.; Wootan, D.W.; Dobbin, K.D.

    1984-08-01

    Fuel burnup and isotopic fission rates were measured in FFTF during acceptance testing in an 8.6 day full power irradiation. Results were compared with three-dimensional diffusion theory calculations based on ENDF/B-V cross sections. A bias of about 3% exists between burnup and fission rate data, although measured axial and radial profiles are in good agreement. The calculated and measured radial power distributions are in disagreement by 6 to 10% from core center to the outer row of fuel. At core center, calculation/experiment (C/E) for isotopic fission rates is generally 1.01 while C/E for burnup is 1.04. Overall measurement uncertainties are 3% and 2% for fission rate and burnup experiments, respectively. Application of the results to a long-range goal of calculating burnup to 1% accuracy is discussed.

  6. OECD/NEA burnup credit calculational criticality benchmark Phase I-B results

    Energy Technology Data Exchange (ETDEWEB)

    DeHart, M.D.; Parks, C.V. [Oak Ridge National Lab., TN (United States); Brady, M.C. [Sandia National Labs., Las Vegas, NV (United States)

    1996-06-01

    In most countries, criticality analysis of LWR fuel stored in racks and casks has assumed that the fuel is fresh with the maximum allowable initial enrichment. This assumption has led to the design of widely spaced and/or highly poisoned storage and transport arrays. If credit is assumed for fuel burnup, initial enrichment limitations can be raised in existing systems, and more compact and economical arrays can be designed. Such reliance on the reduced reactivity of spent fuel for criticality control is referred to as burnup credit. The Burnup Credit Working Group, formed under the auspices of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development, has established a set of well-defined calculational benchmarks designed to study significant aspects of burnup credit computational methods. These benchmarks are intended to provide a means for the intercomparison of computer codes, methods, and data applied in spent fuel analysis. The benchmarks have been divided into multiple phases, each phase focusing on a particular feature of burnup credit analysis. This report summarizes the results and findings of the Phase I-B benchmark, which was proposed to provide a comparison of the ability of different code systems and data libraries to perform depletion analysis for the prediction of spent fuel isotopic concentrations. Results included here represent 21 different sets of calculations submitted by 16 different organizations worldwide and are based on a limited set of nuclides determined to have the most important effect on the neutron multiplication factor of light-water-reactor spent fuel. A comparison of all sets of results demonstrates that most methods agree to within 10% in the ability to estimate the spent fuel concentrations of most actinides. All methods agree within 11% about the average for all fission products studied. Most deviations are less than 10%, and many are less than 5%. The exceptions are Sm 149, Sm 151, and Gd 155.

  7. The effect of dissolved hydrogen on the dissolution of {sup 233}U doped UO{sub 2}(s) high burn-up spent fuel and MOX fuel

    Energy Technology Data Exchange (ETDEWEB)

    Carbol, P. [Inst. for Transuranium Elements, Karlsruhe (Germany); Spahiu, K. (ed.) [and others

    2005-03-01

    In this report the results of the experimental work carried out in a large EU-research project (SFS, 2001-2004) on spent fuel stability in the presence of various amounts of near field hydrogen are presented. Studies of the dissolution of {sup 233}U doped UO{sub 2}(s) simulating 'old' spent fuel were carried out as static leaching tests, autoclave tests with various hydrogen concentrations and electrochemical tests. The results of the leaching behaviour of a high burn-up spent fuel pellet in 5 M NaCl solutions in the presence of 3.2 bar H{sub 2} pressure and of MOX fuel in dilute synthetic groundwater under 53 bar H{sub 2} pressure are also presented. In all the experimental studies carried out in this project, a considerable effect of hydrogen in the dissolution rates of radioactive materials was observed. The experimental results obtained in this project with a-doped UO{sub 2}, high burn-up spent fuel and MOX fuel together with literature data give a reliable background to use fractional alteration/dissolution rates for spent fuel of the order of 10{sup -6}/yr - 10{sup -8}/yr with a recommended value of 4x10{sup -7}/yr for dissolved hydrogen concentrations above 10{sup -3} M and Fe(II) concentrations typical for European repository concepts. Finally, based on a review of the experimental data and available literature data, potential mechanisms of the hydrogen effect are also discussed. The work reported in this document was performed as part of the Project SFS of the European Commission 5th Framework Programme under contract no FIKW-CT-2001-20192 SFS. It represents the deliverable D10 of the experimental work package 'Key experiments using a-doped UO{sub 2} and real spent fuel', coordinated by SKB with the participation of ITU, FZK-INE, ENRESA, CIEMAT, ARMINES-SUBATECH and SKB.

  8. Heterogeneous UO{sub 2} fuel irradiated up to a high burn-up: Investigation of the HBS and of fission product releases

    Energy Technology Data Exchange (ETDEWEB)

    Noirot, J., E-mail: jean.noirot@cea.fr [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Lamontagne, J. [CEA, DEN, DEC, Cadarache, F-13108 St. Paul Lez Durance (France); Nakae, N. [JNES, Toranomon Towers Office, 4-1-28, Toranomon, Minato-ku, Tokyo 105-0001 (Japan); Kitagawa, T. [MNF, 622-1 Funaishikawa, Tokai-mura, Naka-gun, Ibaraki 319-1197 (Japan); Kosaka, Y. [NDC, 622-12 Funaishikawa, Tokai-mura, Ibaraki 319-1111 (Japan); Tverberg, T. [IFE, P.O. Box 173, NO-1751 Halden (Norway)

    2013-11-15

    A UO{sub 2} fuel with a heterogeneous distribution of {sup 235}U was irradiated up to a high burn-up in the Halden Boiling Water Reactor (HBWR). The last 100 days of irradiation were performed with an increased level of linear power. The effect of the heterogeneous fissile isotope distribution on the formation of the HBS was studied free of the possible influence of Pu which exists in heterogeneous MOX fuels. The HBS formed in {sup 235}U-rich agglomerates and its main characteristics were very similar to those of the HBS formed in Pu-rich agglomerates of heterogeneous MOX fuels. The maximum local contents of Nd and Xe before HBS formation were studied in this fuel. In addition to a Pu effect that promotes the HBS phenomenon, comparison with previous results for heterogeneous MOX fuels showed that the local fission product concentration was not the only parameter that has to be taken into consideration. It appears that the local actinide depletion by fission and/or the energy locally deposited through electronic interactions in the fission fragment recoils also have an effect on the HBS formation threshold. Moreover, a major release of fission gases from the peripheral {sup 235}U-rich agglomerates of HBS bubbles and a Cs radial movement are also evidenced in this heterogeneous UO{sub 2}. Cs deposits on the peripheral grain boundaries, including the HBS grain boundaries, are considered to reveal the release paths.

  9. Review of Technical Studies in the United States in Support of Burnup Credit Regulatory Guidance

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, John C [ORNL; Parks, Cecil V [ORNL; Mueller, Don [ORNL; Gauld, Ian C [ORNL

    2010-01-01

    Taking credit for the reduction in reactivity associated with fuel depletion can enable more cost-effective, higher-density storage, transport, disposal, and reprocessing of spent nuclear fuel (SNF) while maintaining sufficient subcritical margin to establish an adequate safety basis. Consequently, there continues to be considerable interest in the United States (U.S.), as well as internationally, in the increased use of burnup credit in SNF operations, particularly related to storage, transport, and disposal of commercial SNF. This interest has motivated numerous technical studies related to the application of burnup credit, both domestically and internationally, as well as the design of SNF storage, transport and disposal systems that rely on burnup credit for maintaining subcriticality. Responding to industry requests and needs, the U.S. Nuclear Regulatory Commission (NRC) initiated a burnup credit research program in 1999, with support from the Oak Ridge National Laboratory (ORNL), to develop regulatory guidance and the supporting technical bases for allowing and expanding the use of burnup credit in pressurized-water reactor SNF storage and transport applications. Although this NRC research program has not been continuous since its inception, considerable progress has been achieved in many key areas in terms of increased understanding of relevant phenomena and issues, availability of relevant information and data, and subsequently updated regulatory guidance for expanded use of burnup credit. This paper reviews technical studies performed by ORNL for the U.S. NRC burnup credit research program. Examples of topics include reactivity effects associated with reactor operating characteristics, fuel assembly characteristics, burnable absorbers, control rods, spatial burnup distributions, cooling time, and assembly misloading; methods and data for validation of isotopic composition predictions; methods and data for validation of criticality calculations; and

  10. Evaluation of Fission Product Critical Experiments and Associated Biases for Burnup Credit Validation

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Rearden, Bradley T [ORNL; Reed, Davis Allan [ORNL

    2010-01-01

    One of the challenges associated with implementation of burnup credit is the validation of criticality calculations used in the safety evaluation; in particular the availability and use of applicable critical experiment data. The purpose of the validation is to quantify the relationship between reality and calculated results. Validation and determination of bias and bias uncertainty require the identification of sets of critical experiments that are similar to the criticality safety models. A principal challenge for crediting fission products (FP) in a burnup credit safety evaluation is the limited availability of relevant FP critical experiments for bias and bias uncertainty determination. This paper provides an evaluation of the available critical experiments that include FPs, along with bounding, burnup-dependent estimates of FP biases generated by combining energy dependent sensitivity data for a typical burnup credit application with the nuclear data uncertainty information distributed with SCALE 6. A method for determining separate bias and bias uncertainty values for individual FPs and illustrative results is presented. Finally, a FP bias calculation method based on data adjustment techniques and reactivity sensitivity coefficients calculated with the SCALE sensitivity/uncertainty tools and some typical results is presented. Using the methods described in this paper, the cross-section bias for a representative high-capacity spent fuel cask associated with the ENDF/B-VII nuclear data for 16 most important stable or near stable FPs is predicted to be no greater than 2% of the total worth of the 16 FPs, or less than 0.13 % k/k.

  11. RELATION BETWEEN PORE MODEL AND CENTER-LINE TEMPERATURE IN HIGH BURN-UP UO2 PELLET

    Directory of Open Access Journals (Sweden)

    Suwardi Suwardi

    2010-06-01

    Full Text Available Relation between pore model and center-line temperature of high burn up UO2 Pellet. Temperature distribution has been evaluated by using different model of pore distribution. Typical data of power distribution and coolant data have been chosen in this study. Different core model and core distribution model have been studied for related temperature, in correlation with high burn up thermal properties. Finite element combined finite different adapted from Saturn-1 has been used for calculating the temperature distribution. The center-line temperature for different pore model and related discussion is presented.   Keywords: pore model, high burn up, UO2 pellet, centerline temperature.

  12. The interest of burnup increase in a context of recycling

    Energy Technology Data Exchange (ETDEWEB)

    Druenne, Hubert [GDF SUEZ-TRACTEBEL, Avenue Ariane 7 - B-1200 Brussels (Belgium)

    2009-06-15

    The current trend is to increase the fuel discharge burnup. In the framework of a recycling policy (closed cycle) higher burnup also affects the quality of the fissile material coming back from the reprocessing. It has the following consequences: - the lower quality of the reprocessed material requires either higher ERU enrichment and/or higher plutonium content in MOX fuel; - should some limits be reached (manufacture limits, maximum {sup 235}U enrichment or Pu content), the energy equivalence could no longer be maintained between recycled fuel assemblies (ERU or MOX) and ENU ones; - in turn, the loss of energy equivalence would request larger feed size, and hence would limit the burnup increase. Consequently, the question is whether an increase in burnup could hamper a recycling policy. In a closed cycle, and considering only the 2. or 3. generation PWR, does the increase in burnup still make it possible to reduce the need for fissile material? Is there an economic optimum? This paper attempts to answer these questions. In conclusions: A. Reprocessing and recycling processes: The present industrial processes technical limits do not hinder reprocessing and recycling of highly burned assemblies (at least in the assumed limit of roughly 65 GWd/t - assembly average). But taking into account the present limitations in terms of initial enrichment, enrichment technology, fuel fabrication and fresh fuel transportation, the additional costs may limit or even over-compensate the benefits resulting from higher discharge burnups. These costs must be known to conclude on the economy of high burnup in a closed cycle policy. B. In-core fuel management: In 18-month cycle, the present 5% enrichment limit is a strong constraint for 'auto-recycling': even with the shortest reprocessing delays as possible, it restricts the achievable batch average discharge burnup to about 56 GWd/t. The economy of high burnup should be analysed in a multi nuclear unit fuel management, with

  13. High-Pressure Liquid Chromatography of Irradiated Nuclear Fue - Separation of Neodymium for Burn-up Determination

    DEFF Research Database (Denmark)

    Larsen, N. R.

    1979-01-01

    Neodymium is separated from solutions of spent nuclear fuel by high-pressure liquid chromatography in methanol-nitric acid-water media using an anion-exchange column. Chromatograms obtained by monitoring at 280 nm, illustrate the difficulties especially with the fission product ruthenium in nuclear...... chemistry. Preseparation of the rare earths and trivalent actinides using a di(2-ethylhexyl)phosphoric acid/kieselguhr column is described....

  14. Dependence of control rod worth on fuel burnup

    Energy Technology Data Exchange (ETDEWEB)

    Savva, P., E-mail: savvapan@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Varvayanni, M., E-mail: melina@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece); Catsaros, N., E-mail: nicos@ipta.demokritos.g [NCSR ' DEMOKRITOS' , PoB 60228, 15310 Aghia Paraskevi (Greece)

    2011-02-15

    Research highlights: Diffusion and MC calculations for rod worth dependence on burnup and Xe in reactors. One-step rod withdrawal/insertion are used for rod worth estimation. The study showed that when Xe is present the rods worth is significantly reduced. Rod worth variation with burnup depends on rod position in core. Rod worth obtained with MC code is higher than that obtained from deterministic. - Abstract: One important parameter in the design and the analysis of a nuclear reactor core is the reactivity worth of the control rods, i.e. their efficiency to absorb excess reactivity. The control rod worth is affected by parameters such as the fuel burnup in the rod vicinity, the Xe concentration in the core, the operational time of the rod and its position in the core. In the present work, two different computational approaches, a deterministic and a stochastic one, were used for the determination of the rods worth dependence on the fuel burnup level and the Xe concentration level in a conceptual, symmetric reactor core, based on the MTR fuel assemblies used in the Greek Research Reactor (GRR-1). For the deterministic approach the neutronics code system composed by the SCALE modules NITAWL and XSDRN and the diffusion code CITATION was used, while for the stochastic one the Monte Carlo code TRIPOLI was applied. The study showed that when Xe is present in the core, the rods worth is significantly reduced, while the rod worth variation with increasing burnup depends on the rods position in the core grid. The rod worth obtained with the use of the Monte Carlo code is higher than the one obtained from the deterministic code.

  15. Experimental results and analysis of core physics experiments, FUBILA, for high burn-up BWR full MOX cores

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, T.; Kikuchi, S.; Kawashima, K.; Kamimura, K. [Japan Nuclear Energy Safety Organization, 3-17-1, Toranomon, Minato-ku, Tokyo 105-0001 (Japan)

    2006-07-01

    JNES has been performing MOX core physics experiments, FUBILA, in the EOLE critical facility of the CEA Cadarache center with collaboration of a French Consortium (CEA and COGEMA). The experiments have been designed to obtain the core physics data of operating conditions of full MOX BWR cores consisting of high burn up BWR MOX assemblies. The experiments consisting of seven different core configurations started from January 2005 and will be completed by August 2006. Theoretical analysis of the experimental data has been also carried out using a deterministic code, SRAC, and a continuous energy Monte Carlo calculation code, MVP, with major nuclear data libraries, JENDL-3.3, 3.2, ENDF/B-VI and JEFF-3.1 for the first critical core. (authors)

  16. Thermal behavior analysis of PWR fuel during RIA at various fuel burnups using modified theatre code

    Directory of Open Access Journals (Sweden)

    Nawaz Amjad

    2016-01-01

    Full Text Available The fuel irradiation and burnup causes geometrical and dimensional changes in the fuel rod which affects its thermal resistance and ultimately affects the fuel rod behavior during steady-state and transient conditions. The consistent analysis of fuel rod thermal performance is essential for precise evaluation of reactor safety in operational transients and accidents. In this work, analysis of PWR fuel rod thermal performance is carried out under steady-state and transient conditions at different fuel burnups. The analysis is performed by using thermal hydraulic code, THEATRe. The code is modified by adding burnup dependent fuel rod behavior models. The original code uses as-fabricated fuel rod dimensions during steady-state and transient conditions which can be modified to perform more consistent reactor safety analysis. AP1000 reactor is considered as a reference reactor for this analysis. The effect of burnup on steady-state fuel rod parameters has been investigated. For transient analysis, hypothetical reactivity initiated accident was simulated by considering a triangular power pulse of variable pulse height (relative to the full power reactor operating conditions and pulse width at different fuel burnups which corresponds to fresh fuel, low and medium burnup fuels. The effect of power pulse height, pulse width and fuel burnup on fuel rod temperatures has been investigated. The results of reactivity initiated accident analysis show that the fuel failure mechanisms are different for fresh fuel and fuel at different burnup levels. The fuel failure in fresh fuel is expected due to fuel melting as fuel temperature increases with increase in pulse energy (pulse height. However, at relatively higher burnups, the fuel failure is expected due to cladding failure caused by strong pellet clad mechanical interaction, where, the contact pressure increases beyond the cladding yield strength.

  17. Preliminary 3D burn-up analysis of the HPLWR core

    Energy Technology Data Exchange (ETDEWEB)

    Monti, Lanfranco; Gabrielli, Fabrizio; Schulenberg, Thomas [Forschungszentrum Karlsruhe (Germany). Inst. for Nuclear and Energy Technologies

    2009-07-01

    The High Performance Light Water Reactor (HPLWR) is an innovative reactor concept cooled and moderated with water at supercritical pressure (25 MPa) whose feasibility is analyzed within a European framework [1]. The pronounced variation in water density, which takes place inside the core, is due to the coolant heat up from 550 K to 800 K and is supposed to generate pronounced 3D effects during reactor operation because the different core regions have different flux amplitude and neutron spectrum. Open questions are how k{sub eff} and the power-map will change during the burn-up and require a 3D multi-zone burn-up analysis of the core. This goal is achieved using the ERANOS system [2, 3], which is a deterministic tool for neutronic core analyses. The starting condition is taken from a neutronic/thermal-hydraulic coupled solution of the whole core [4], which does not yet include any fuel enrichment optimization nor reactivity control systems, i.e. control rods or burnable poisons. Uranium dioxide enriched to 5wt% in {sup 235}U is used as starting fuel while typical LWRs evolution chains for actinides and fission products have been selected. The core nodalization used in the coupled system is also adopted for multi-zone burn-up analysis: there are 462 zones with different material composition, 21 in axial direction and 22 in the horizontal plane. A burn-up period of 200 days ({approx_equal}6400 MWd/tHM) is considered here and has been divided into two different smaller time steps: 1) an inner time step at which macroscopic cross-sections (XSs) and the flux normalization are calculated according to the change in fuel isotopic composition; 2) an outer time step at which whole core flux calculations are performed to evaluate the region-wise neutron flux distribution. The length of the flux calculation time step has to be short enough to avoid unphysical power-shape oscillations, as underlined by Reiss et al. [5] with a different computational approach. The 40 groups

  18. Burn-up calculation of different thorium-based fuel matrixes in a thermal research reactor using MCNPX 2.6 code

    Directory of Open Access Journals (Sweden)

    Gholamzadeh Zohreh

    2014-12-01

    Full Text Available Decrease of the economically accessible uranium resources and the inherent proliferation resistance of thorium fuel motivate its application in nuclear power systems. Estimation of the nuclear reactor’s neutronic parameters during different operational situations is of key importance for the safe operation of nuclear reactors. In the present research, thorium oxide fuel burn-up calculations for a demonstrative model of a heavy water- -cooled reactor have been performed using MCNPX 2.6 code. Neutronic parameters for three different thorium fuel matrices loaded separately in the modelled thermal core have been investigated. 233U, 235U and 239Pu isotopes have been used as fissile element in the thorium oxide fuel, separately. Burn-up of three different fuels has been calculated at 1 MW constant power. 135X and 149Sm concentration variations have been studied in the modelled core during 165 days burn-up. Burn-up of thorium oxide enriched with 233U resulted in the least 149Sm and 135Xe productions and net fissile production of 233U after 165 days. The negative fuel, coolant and void reactivity of the used fuel assures safe operation of the modelled thermal core containing (233U-Th O2 matrix. Furthermore, utilisation of thorium breeder fuel demonstrates several advantages, such as good neutronic economy, 233U production and less production of long-lived α emitter high radiotoxic wastes in biological internal exposure point of view

  19. A Criticality Evaluation of the GBC-32 Dry Storage Cask in PWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Hyoungju; Park, Kwangheon; Hong, Ser Gi [Kyung Hee Univ., Yongin (Korea, Republic of)

    2015-05-15

    The current criticality safety evaluation assumes the only unirradiated fresh fuels with the maximum enrichment in a dry storage cask (DSC) for conservatism without consideration of the depletion of fissile nuclides and the generation of neutron-absorbing fission products. However, the large conservatism leads to the significant increase of the storage casks required. Thus, the application of burnup credit which takes credit for the reduction of reactivity resulted from fuel depletion can increase the capacity in storage casks. On the other hand, the burnup credit application introduces lots of complexity into a criticality safety analysis such as the accurate estimation of the isotopic inventories and the burnup of UNFs and the validation of the criticality calculation. The criticality evaluation with an effect of burnup credit was performed for the DSC of GBC-32 by using SCALE 6.1/STARBUCS. keff values were calculated as a function of burnup and cooling time for four initial enrichments of 2, 3, 4, and 5 wt. % 235U. The values were calculated for the burnup range of 0 to 60,000 MWD/MTU, in increments of 10,000 MWD/MTU, and for five cooling times of 0, 5, 10, 20, and 40 years.

  20. On the Inclusion of Inorganic Chemical Reactivity in High School Chemistry: The Reactivity Network.

    Science.gov (United States)

    Mellon, E. K.

    1989-01-01

    Reports the function of the Reactivity Network which is to translate reactivity data from the primary literature into some 30 reviews for high school teachers and curriculum developers and to disseminate that information nationwide. Discusses a needs assessment done for the project. (MVL)

  1. A criticality analysis of the GBC-32 dry storage cask with Hanbit nuclear power plant unit 3 fuel assemblies from the viewpoint of burnup credit

    Energy Technology Data Exchange (ETDEWEB)

    Yun, Hyung Ju; Kim, Do Yeon; Park, Kwang Heon; Hong, Ser Gi [Dept. of Nuclear Engineering, Kyung Hee University, Seoul (Korea, Republic of)

    2016-06-15

    Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that keff values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

  2. Benefits of the delta K of depletion benchmarks for burnup credit validation

    Energy Technology Data Exchange (ETDEWEB)

    Lancaster, D. [NuclearConsultants.com, 187 Faith Circle, Boalsburg, PA 16827 (United States); Machiels, A. [Electric Power Research Inst., Inc., 3420 Hillview Avenue, Palo Alto, CA 94304 (United States)

    2012-07-01

    Pressurized Water Reactor (PWR) burnup credit validation is demonstrated using the benchmarks for quantifying fuel reactivity decrements, published as 'Benchmarks for Quantifying Fuel Reactivity Depletion Uncertainty,' EPRI Report 1022909 (August 2011). This demonstration uses the depletion module TRITON available in the SCALE 6.1 code system followed by criticality calculations using KENO-Va. The difference between the predicted depletion reactivity and the benchmark's depletion reactivity is a bias for the criticality calculations. The uncertainty in the benchmarks is the depletion reactivity uncertainty. This depletion bias and uncertainty is used with the bias and uncertainty from fresh UO{sub 2} critical experiments to determine the criticality safety limits on the neutron multiplication factor, k{sub eff}. The analysis shows that SCALE 6.1 with the ENDF/B-VII 238-group cross section library supports the use of a depletion bias of only 0.0015 in delta k if cooling is ignored and 0.0025 if cooling is credited. The uncertainty in the depletion bias is 0.0064. Reliance on the ENDF/B V cross section library produces much larger disagreement with the benchmarks. The analysis covers numerous combinations of depletion and criticality options. In all cases, the historical uncertainty of 5% of the delta k of depletion ('Kopp memo') was shown to be conservative for fuel with more than 30 GWD/MTU burnup. Since this historically assumed burnup uncertainty is not a function of burnup, the Kopp memo's recommended bias and uncertainty may be exceeded at low burnups, but its absolute magnitude is small. (authors)

  3. Manufacturing Data Uncertainties Propagation Method in Burn-Up Problems

    Directory of Open Access Journals (Sweden)

    Thomas Frosio

    2017-01-01

    Full Text Available A nuclear data-based uncertainty propagation methodology is extended to enable propagation of manufacturing/technological data (TD uncertainties in a burn-up calculation problem, taking into account correlation terms between Boltzmann and Bateman terms. The methodology is applied to reactivity and power distributions in a Material Testing Reactor benchmark. Due to the inherent statistical behavior of manufacturing tolerances, Monte Carlo sampling method is used for determining output perturbations on integral quantities. A global sensitivity analysis (GSA is performed for each manufacturing parameter and allows identifying and ranking the influential parameters whose tolerances need to be better controlled. We show that the overall impact of some TD uncertainties, such as uranium enrichment, or fuel plate thickness, on the reactivity is negligible because the different core areas induce compensating effects on the global quantity. However, local quantities, such as power distributions, are strongly impacted by TD uncertainty propagations. For isotopic concentrations, no clear trends appear on the results.

  4. A simple gamma spectrometry method for evaluating the burnup of MTR-type HEU fuel elements

    Energy Technology Data Exchange (ETDEWEB)

    Makmal, T. [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel); Nuclear Physics and Engineering Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Aviv, O. [Radiation Safety Division, Soreq Nuclear Research Center, Yavne 81800 (Israel); Gilad, E., E-mail: gilade@bgu.ac.il [The Unit of Nuclear Engineering, Ben-Gurion University of The Negev, Beer-Sheva 84105 (Israel)

    2016-10-21

    A simple method for the evaluation of the burnup of a materials testing reactor (MTR) fuel element by gamma spectrometry is presented. The method was applied to a highly enriched uranium MTR nuclear fuel element that was irradiated in a 5 MW pool-type research reactor for a total period of 34 years. The experimental approach is based on in-situ measurements of the MTR fuel element in the reactor pool by a portable high-purity germanium detector located in a gamma cell. To corroborate the method, analytical calculations (based on the irradiation history of the fuel element) and computer simulations using a dedicated fuel cycle burnup code ORIGEN2 were performed. The burnup of the MTR fuel element was found to be 52.4±8.8%, which is in good agreement with the analytical calculations and the computer simulations. The method presented here is suitable for research reactors with either a regular or an irregular irradiation regime and for reactors with limited infrastructure and/or resources. In addition, its simplicity and the enhanced safety it confers may render this method suitable for IAEA inspectors in fuel element burnup assessments during on-site inspections. - Highlights: • Simple, inexpensive, safe and flexible experimental setup that can be quickly deployed. • Experimental results are thoroughly corroborated against ORIGEN2 burnup code. • Experimental uncertainty of 9% and 5% deviation between measurements and simulations. • Very high burnup MTR fuel element is examined, with 60% depletion of {sup 235}U. • Impact of highly irregular irradiation regime on burnup evaluation is studied.

  5. Tritium release from EXOTIC-7 orthosilicate pebbles. Effect of burnup and contact with beryllium during irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Scaffidi-Argentina, F.; Werle, H. [Forschungszentrum Karlsruhe GmbH Technik und Umwelt (Germany). Inst. fuer Neutronenphysik und Reaktortechnik

    1998-03-01

    EXOTIC-7 was the first in-pile test with {sup 6}Li-enriched (50%) lithium orthosilicate (Li{sub 4}SiO{sub 4}) pebbles and with DEMO representative Li-burnup. Post irradiation examinations of the Li{sub 4}SiO{sub 4} have been performed at the Forschungszentrum Karlsruhe (FZK), mainly to investigate the tritium release kinetics as well as the effect of Li-burnup and/or contact with beryllium during irradiation. The release rate of Li{sub 4}SiO{sub 4} from pure Li{sub 4}SiO{sub 4} bed of capsule 28.1-1 is characterized by a broad main peak at about 400degC and by a smaller peak at about 800degC, and that from the mixed beds of capsule 28.2 and 26.2-1 shows again these two peaks, but most of the tritium is now released from the 800degC peak. This shift of release from low to high temperature may be due to the higher Li-burnup and/or due to contact with Be during irradiation. Due to the very difficult interpretation of the in-situ tritium release data, residence times have been estimated on the basis of the out-of-pile tests. The residence time for Li{sub 4}SiO{sub 4} from caps. 28.1-1 irradiated at 10% Li-burnup agrees quite well with that of the same material irradiated at Li-burnup lower than 3% in the EXOTIC-6 experiment. In spite of the observed shift in the release peaks from low to high temperature, also the residence time for Li{sub 4}SiO{sub 4} from caps. 26.2-1 irradiated at 13% Li-burnup agrees quite well with the data from EXOTIC-6 experiment. On the other hand, the residence time for Li{sub 4}SiO{sub 4} from caps. 28.2 (Li-burnup 18%) is about a factor 1.7-3.8 higher than that for caps. 26.2-1. Based on these data on can conclude that up to 13% Li-burnup neither the contact with beryllium nor the Li-burnup have a detrimental effect on the tritium release of Li{sub 4}SiO{sub 4} pebbles, but at 18% Li-burnup the residence time is increased by about a factor three. (J.P.N.)

  6. Development of burnup dependent fuel rod model in COBRA-TF

    Science.gov (United States)

    Yilmaz, Mine Ozdemir

    The purpose of this research was to develop a burnup dependent fuel thermal conductivity model within Pennsylvania State University, Reactor Dynamics and Fuel Management Group (RDFMG) version of the subchannel thermal-hydraulics code COBRA-TF (CTF). The model takes into account first, the degradation of fuel thermal conductivity with high burnup; and second, the fuel thermal conductivity dependence on the Gadolinium content for both UO2 and MOX fuel rods. The modified Nuclear Fuel Industries (NFI) model for UO2 fuel rods and Duriez/Modified NFI Model for MOX fuel rods were incorporated into CTF and fuel centerline predictions were compared against Halden experimental test data and FRAPCON-3.4 predictions to validate the burnup dependent fuel thermal conductivity model in CTF. Experimental test cases from Halden reactor fuel rods for UO2 fuel rods at Beginning of Life (BOL), through lifetime without Gd2O3 and through lifetime with Gd 2O3 and a MOX fuel rod were simulated with CTF. Since test fuel rod and FRAPCON-3.4 results were based on single rod measurements, CTF was run for a single fuel rod surrounded with a single channel configuration. Input decks for CTF were developed for one fuel rod located at the center of a subchannel (rod-centered subchannel approach). Fuel centerline temperatures predicted by CTF were compared against the measurements from Halden experimental test data and the predictions from FRAPCON-3.4. After implementing the new fuel thermal conductivity model in CTF and validating the model with experimental data, CTF model was applied to steady state and transient calculations. 4x4 PWR fuel bundle configuration from Purdue MOX benchmark was used to apply the new model for steady state and transient calculations. First, one of each high burnup UO2 and MOX fuel rods from 4x4 matrix were selected to carry out single fuel rod calculations and fuel centerline temperatures predicted by CTF/TORT-TD were compared against CTF /TORT-TD /FRAPTRAN

  7. Some fundamental aspects of highly reactive iron coke production

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, S.; Terashima, H.; Sato, E.; Naito, M. [Nippon Steel Corp. Ltd., Chiba (Japan)

    2007-07-01

    It is important to develop the production and utilization technology of highly reactive coke in order to improve the efficiency of blast furnace reactions. In this study, some fundamental aspects of highly reactive iron coke produced in a coke oven chamber were investigated. First, the effects of catalytic Fe powder addition to coal before carbonization on coke strength were investigated. The addition of Fe powder decreased the coal caking property and hence the resultant coke drum index. On the other hand it increased coke reactivity (JIS coke reactivity index and CRI) to a great extent. This means that the caking property of blended coals needs to be adjusted higher to produce iron coke with required strength and high reactivity. Secondly, it was shown that the iron ore reacts with silica brick at 1200{sup o}C in a condition similar to that in a coke oven chamber. The iron ore and silica reacted to produce fayalite and the brick was damaged. On the other hand, it was proven that the iron ore does not react with silica brick at 1100{sup o}C in the above condition. Based on this fundamental study, iron coke with proper strength and high reactivity was successfully produced in a coke oven chamber on a commercial scale by adjusting the coal blend composition and the coke oven temperature. Furthermore it was revealed that about 70 % of iron in iron ore powder added to coal was reduced to metallic iron during carbonization.

  8. The Impact of Operating Parameters and Correlated Parameters for Extended BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Marshall, William B. J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ilas, Germina [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Betzler, Benjamin R. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-06-01

    Applicants for certificates of compliance for spent nuclear fuel (SNF) transportation and dry storage systems perform analyses to demonstrate that these systems are adequately subcritical per the requirements of Title 10 of the Code of Federal Regulations (10 CFR) Parts 71 and 72. For pressurized water reactor (PWR) SNF, these analyses may credit the reduction in assembly reactivity caused by depletion of fissile nuclides and buildup of neutron-absorbing nuclides during power operation. This credit for reactivity reduction during depletion is commonly referred to as burnup credit (BUC). US Nuclear Regulatory Commission (NRC) staff review BUC analyses according to the guidance in the Division of Spent Fuel Storage and Transportation Interim Staff Guidance (ISG) 8, Revision 3, Burnup Credit in the Criticality Safety Analyses of PWR Spent Fuel in Transportation and Storage Casks.

  9. Investigation of burnup credit allowance in the criticality safety evaluation of spent fuel casks

    Energy Technology Data Exchange (ETDEWEB)

    Lake, W.H. (USDOE, Washington, DC (USA)); Sanders, T.L. (Sandia National Labs., Albuquerque, NM (USA)); Parks, C.V. (Oak Ridge National Lab., TN (USA))

    1990-01-01

    This presentation discusses work in progress on criticality analysis verification for designs which take account of the burnup and age of transported fuel. The work includes verification of cross section data, correlation with experiments, proper extension of the methods into regimes not covered by experiments, establishing adequate reactivity margins, and complete documentation of the project. Recommendations for safe operational procedures are included, as well as a discussion of the economic and safety benefits of such designs.

  10. A Simple Formula for Local Burnup and Isotope Distributions Based on Approximately Constant Relative Reaction Rate

    Directory of Open Access Journals (Sweden)

    Cenxi Yuan

    2016-01-01

    Full Text Available A simple and analytical formula is suggested to solve the problems of the local burnup and the isotope distributions. The present method considers two extreme conditions of neutrons penetrating the fuel rod. Based on these considerations, the formula is obtained to calculate the reaction rates of 235U, 238U, and 239Pu and straightforward the local burnup and the isotope distributions. Starting from an initial burnup level, the parameters of the formula are fitted to the reaction rates given by a Monte Carlo (MC calculation. Then the present formula independently gives very similar results to the MC calculation from the starting to high burnup level but takes just a few minutes. The relative reaction rates are found to be almost independent of the radius (except (n,γ of  238U and the burnup, providing a solid background for the present formula. A more realistic examination is also performed when the fuel rods locate in an assembly. A combination of the present formula and the MC calculation is expected to have a nice balance between the numerical accuracy and time consumption.

  11. AREVA NP burnup credit investigation on irradiated MOX fuel within the REBUS BWR programme

    Energy Technology Data Exchange (ETDEWEB)

    Alander, Alexandra; Misu, Stefan; Timm, Wolf [AREVA, AREVA NP, Erlangen (Germany); Thareau, Sebastien [AREVA, AREVA NP, Paris (France)

    2008-07-01

    The present paper summarizes a criticality and burnup credit investigation carried out using the 2D spectral codes CASMO-4 and APOLLO2-A. Fission rate distributions and multiplication factors, for UOX and MOX configurations, are calculated as well as the reactivity effect caused by burnup on a selection of irradiated MOX fuel assemblies. 3D core criticality calculations were carried out with the Monte Carlo transport code MOCA and the deterministic transport code VARIANT (a nodal code developed by ANL) using CASMO-4 generated cross section libraries. Calculations were compared to experimental data from the critical facility VENUS in the context of the REBUS BWR Programme. The results confirm that the spectral codes CASMO-4 and APOLLO2-A are well suited to calculate fission rates, multiplication factors and reactivity effects. It is also found that the calculated burnup reactivity effect, using CASMO-4 generated cross sections and the best 3D method (MOCA), is underestimated by merely 7% compared to the experimental value, which can mainly be attributed to the simplifications done in order to model the critical configurations with reasonable efforts. (authors)

  12. Some fundamental aspects of highly reactive iron coke production

    Energy Technology Data Exchange (ETDEWEB)

    Seiji Nomura; Hidetoshi Terashima; Eiji Sato; Masaaki Naito [Nippon Steel Corporation, Chiba (Japan). Environment and Process Technology Center

    2007-07-01

    It is important to develop the production and utilization technology of highly reactive coke in order to improve the efficiency of blast furnace reactions. In this study, some fundamental aspects of highly reactive iron coke produced in a coke oven chamber were investigated. First, the effects of catalytic Fe powder addition to coal before carbonization on coke strength were investigated. The addition of Fe powder decreased the coal caking property and hence the resultant coke drum index (DI150 15). On the other hand it increased coke reactivity (JIS coke reactivity index and CRI) to a great extent. This means that the caking property of blended coals needs to be adjusted higher to produce iron coke with proper strength and high reactivity. Secondly, it was shown that the iron ore reacts with silica brick at 1200{sup o}C in a condition similar to that in a coke oven chamber. The iron ore and silica reacted to produce fayalite (2FeO{center_dot}SiO{sub 2}) and the brick was damaged. On the other hand, it was proven that the iron ore does not react with silica brick at 1100{sup o}C in the above condition. Based on this fundamental study, iron coke with proper strength and high reactivity was successfully produced in a coke oven chamber on a commercial scale by adjusting the coal blend composition and the coke oven temperature. Furthermore it was revealed that about 70% of iron in iron ore powder added to coal was reduced to metallic iron during carbonization in coke ovens.

  13. Some fundamental aspects of highly reactive iron coke production

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, S.; Terashima, H.; Sato, E.; Naito, M. [Nippon Steel Corp. Ltd., Futtsu (Japan)

    2006-12-15

    The development of production and utilization technology of highly reactive coke is significant in order to improve blast furnace reaction efficiency. In this report, some fundamental aspects of highly reactive iron coke produced in a coke oven chamber were investigated. First, the effects of catalytic Fe powder addition to coal before carbonization on coke strength were investigated. The addition of Fe powder decreased coal caking property and hence resultant coke drum index (DI{sup 150}{sub 15}). On the other hand it increased coke reactivity (JIS coke reactivity index and CRI) to a great extent. This means that caking property of blended coals needs to be adjusted higher to produce the iron coke with proper strength and high reactivity. Secondly, it was shown that the iron ore reacts with silica brick at 1200{sup o}C in a condition similar to that in a coke oven chamber. The iron ore and silica reacted to produce fayalite (2FeO {center_dot}SiO{sub 2}) and the brick was damaged. On the other hand, it was proved that the iron ore does not react with silica brick at 1100{sup o}C in the above condition. Based on this fundamental study, the iron coke with proper strength and high reactivity was successfully produced in coke ovens on a commercial scale by adjusting the coal blend composition and the coke oven temperature. Furthermore it was revealed that about 70% of iron in iron ore powder added to coal was reduced to metallic iron during carbonization in coke ovens.

  14. Nuclear Energy Research Initiative. Development of a Stabilized Light Water Reactor Fuel Matrix for Extended Burnup

    Energy Technology Data Exchange (ETDEWEB)

    BD Hanson; J Abrefah; SC Marschman; SG Prussin

    2000-09-08

    The main objective of this project is to develop an advanced fuel matrix capable of achieving extended burnup while improving safety margins and reliability for present operations. In the course of this project, the authors improve understanding of the mechanism for high burnup structure (HBS) formation and attempt to design a fuel to minimize its formation. The use of soluble dopants in the UO{sub 2} matrix to stabilize the matrix and minimize fuel-side corrosion of the cladding is the main focus.

  15. High-sensitivity C-reactive protein, lipid profile, malondialdehyde ...

    African Journals Online (AJOL)

    High-sensitivity C-reactive protein, lipid profile, malondialdehyde and total antioxidant capacity in psoriasis. ... Abstract. Psoriasis is a chronic inflammatory skin disease characterized by epidermal hyperproliferation and lymphocytic infiltration. The ongoing inflammatory process in psoriasis affects the arterial wall promoting ...

  16. Compound effects of operating parameters on burnup credit criticality analysis in boiling water reactor spent fuel assemblies

    Directory of Open Access Journals (Sweden)

    Shang-Chien Wu

    2018-02-01

    Full Text Available This study proposes a new method of analyzing the burnup credit in boiling water reactor spent fuel assemblies against various operating parameters. The operating parameters under investigation include fuel temperature, axial burnup profile, axial moderator density profile, and control blade usage. In particular, the effects of variations in one and two operating parameters on the curve of effective multiplication factor (keff versus burnup (B are, respectively, the so-called single and compound effects. All the calculations were performed using SCALE 6.1 together with the Evaluated Nuclear Data Files, part B (ENDF/B-VII238-neutron energy group data library. Furthermore, two geometrical models were established based on the General Electric (GE14 10 × 10 boiling water reactor fuel assembly and the Generic Burnup-Credit (GBC-68 storage cask. The results revealed that the curves of keff versus B, due to single and compound effects, can be approximated using a first degree polynomial of B. However, the reactivity deviation (or changes of keff,Δk in some compound effects was not a summation of the all Δk resulting from the two associated single effects. This phenomenon is undesirable because it may to some extent affect the precise assessment of burnup credit. In this study, a general formula was thus proposed to express the curves of keff versus B for both single and compound effects.

  17. Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity

    Science.gov (United States)

    Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

    2002-01-01

    A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

  18. Hydride reorientation and its impact on ambient temperature mechanical properties of high burn-up irradiated and unirradiated recrystallized Zircaloy-2 nuclear fuel cladding with an inner liner

    Science.gov (United States)

    Auzoux, Q.; Bouffioux, P.; Machiels, A.; Yagnik, S.; Bourdiliau, B.; Mallet, C.; Mozzani, N.; Colas, K.

    2017-10-01

    Precipitation of radial hydrides in zirconium-based alloy cladding concomitant with the cooling of spent nuclear fuel during dry storage can potentially compromise cladding integrity during its subsequent handling and transportation. This paper investigates hydride reorientation and its impact on ductility in unirradiated and irradiated recrystallized Zircaloy-2 cladding with an inner liner (cladding for boiling water reactors) subjected to hydride reorientation treatments. Cooling from 400 °C, hydride reorientation occurs in recrystallized Zircaloy-2 with liner at a lower effective stress in irradiated samples (below 40 MPa) than in unirradiated specimens (between 40 and 80 MPa). Despite significant hydride reorientation, unirradiated recrystallized Zircaloy-2 with liner cladding containing ∼200 wppm hydrogen shows a high diametral strain at fracture (>15%) during burst tests at ambient temperature. This ductile behavior is due to (1) the lower yield stress of the recrystallized cladding materials in comparison to hydride fracture strength (corrected by the compression stress arising from the precipitation) and (2) the hydride or hydrogen-depleted zone as a result of segregation of hydrogen into the liner layer. In irradiated Zircaloy-2 with liner cladding containing ∼340 wppm hydrogen, the conservation of some ductility during ring tensile tests at ambient temperature after reorientation treatment at 400 °C with cooling rates of ∼60 °C/h is also attributed to the existence of a hydride-depleted zone. Treatments at lower cooling rates (∼6 °C/h and 0.6 °C/h) promote greater levels of hydrogen segregation into the liner and allow for increased irradiation defect annealing, both of which result in a significant increase in ductility. Based on this investigation, given the very low cooling rates typical of dry storage systems, it can be concluded that the thermal transients associated with dry storage should not degrade, and more likely should actually

  19. Estimation of the Fuel Depletion Code Bias and Uncertainty in Burnup-Credit Criticality Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Woon; Cho, Nam Zin [Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of); Lee, Sang Jin; Bae, Chang Yeal [Nuclear Environment Technology Institute, Taejon (Korea, Republic of)

    2006-07-01

    In the past, criticality safety analyses for commercial light-water-reactor (LWR) spent nuclear fuel (SNF) storage and transportation canisters assumed the spent fuel to be fresh (unirradiated) fuel with uniform isotopic compositions. This fresh-fuel assumption provides a well-defined, bounding approach to the criticality safety analysis that eliminates concerns related to the fuel operating history, and thus considerably simplifies the safety analysis. However, because this assumption ignores the inherent decrease in reactivity as a result of irradiation, it is very conservative. The concept of taking credit for the reduction in reactivity due to fuel burnup is commonly referred to as burnup credit. Implementation of burnup credit requires the computational prediction of the nuclide inventories (compositions) for the dominant fissile and absorbing nuclide species in spent fuel. In addition to that, the bias and uncertainty in the predicted concentration of all nuclides used in the analysis be established by comparisons of calculated and measured radiochemical assay data. In this paper, three methods for considering the bias and uncertainty will be reviewed. The estimated bias and uncertainty that the results of 3rd method are presented.

  20. Needs of reliable nuclear data and covariance matrices for Burnup Credit in JEFF-3 library

    Directory of Open Access Journals (Sweden)

    Lecarpentier D.

    2013-03-01

    Full Text Available Burnup Credit (BUC is the concept which consists in taking into account credit for the reduction of nuclear spent fuel reactivity due to its burnup. In the case of PWR-MOx spent fuel, studies pointed out that the contribution of the 15 most absorbing, stable and non-volatile fission products selected to the credit is as important as the one of the actinides. In order to get a “best estimate” value of the keff, biases of their inventory calculation and individual reactivity worth should be considered in criticality safety studies. This paper enhances the most penalizing bias towards criticality and highlights possible improvements of nuclear data for the 15 FPs of PWRMOx BUC. Concerning the fuel inventory, trends in function of the burnup can be derived from experimental validation of the DARWIN-2.3 package (using the JEFF-3.1.1/SHEM library. Thanks to the BUC oscillation programme of separated FPs in the MINERVE reactor and fully validated scheme PIMS, calculation over experiment ratios can be accurately transposed to tendencies on the FPs integral cross sections.

  1. Deep Reactive Ion Etching for High Aspect Ratio Microelectromechanical Components

    DEFF Research Database (Denmark)

    Jensen, Søren; Yalcinkaya, Arda Deniz; Jacobsen, S.

    2004-01-01

    A deep reactive ion etch (DRIE) process for fabrication of high aspect ratio trenches has been developed. Trenches with aspect ratios exceeding 20 and vertical sidewalls with low roughness have been demonstrated. The process has successfully been used in the fabrication of silicon-on-insulator (SOI......) released comb drive based resonators and tunable capacitors for MEMS applications. Brief characterizations of the devices are presented....

  2. [Physical state of adolescents with the high stress reactivity].

    Science.gov (United States)

    Krivolapchuk, I A

    2012-01-01

    Research objective was studying of features of a physical state (PS) adolescents of 13-14 years with high (n = 97) and low (n = 85) level of stress reactivity. The obtained data testify that in puberty formation of mechanisms of energy supply for muscle activity at adolescents with various level of stress reactivity occurs heterochronic and nonlinearly. Thus hyperreactivity boys of 13-14 years are characterised concerning high anaerobic alactic and the low aerobic productivity of the organism raised by physiological working costs and slowed down restoration after loadings of the big and submaximum capacity. Specificity of physical readiness of hyperreactivity teenagers consists that at them the high level of development of speed and force is combined with rather low level of development of the general endurance. Intergroup distinctions concerning muscular working capacity and the impellent readiness, caused by stress reactivity, are shown at adolescents of 13-14 years at different stages of puberty (SP). Thus and hyper--and hyporeactivity boys with II and III SP, are characterised in comparison with children with IV SP higher indicators of aerobic productivity of an organism, against rather small anaerobic possibilities. Results of research give the basis to believe, that at hyporeactivity adolescents efficiency of functioning of mechanisms of antihypoxic protection is lowered.

  3. Propagation of statistical and nuclear data uncertainties in Monte Carlo burn-up calculations

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Herranz, Nuria [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid, UPM (Spain)], E-mail: nuria@din.upm.es; Cabellos, Oscar [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid, UPM (Spain); Sanz, Javier [Departamento de Ingenieria Energetica, Universidad Nacional de Educacion a Distancia, UNED (Spain); Juan, Jesus [Laboratorio de Estadistica, Universidad Politecnica de Madrid, UPM (Spain); Kuijper, Jim C. [NRG - Fuels, Actinides and Isotopes Group, Petten (Netherlands)

    2008-04-15

    Two methodologies to propagate the uncertainties on the nuclide inventory in combined Monte Carlo-spectrum and burn-up calculations are presented, based on sensitivity/uncertainty and random sampling techniques (uncertainty Monte Carlo method). Both enable the assessment of the impact of uncertainties in the nuclear data as well as uncertainties due to the statistical nature of the Monte Carlo neutron transport calculation. The methodologies are implemented in our MCNP-ACAB system, which combines the neutron transport code MCNP-4C and the inventory code ACAB. A high burn-up benchmark problem is used to test the MCNP-ACAB performance in inventory predictions, with no uncertainties. A good agreement is found with the results of other participants. This benchmark problem is also used to assess the impact of nuclear data uncertainties and statistical flux errors in high burn-up applications. A detailed calculation is performed to evaluate the effect of cross-section uncertainties in the inventory prediction, taking into account the temporal evolution of the neutron flux level and spectrum. Very large uncertainties are found at the unusually high burn-up of this exercise (800 MWd/kgHM). To compare the impact of the statistical errors in the calculated flux with respect to the cross uncertainties, a simplified problem is considered, taking a constant neutron flux level and spectrum. It is shown that, provided that the flux statistical deviations in the Monte Carlo transport calculation do not exceed a given value, the effect of the flux errors in the calculated isotopic inventory are negligible (even at very high burn-up) compared to the effect of the large cross-section uncertainties available at present in the data files.

  4. Dependence of heavy metal burnup on nuclear data libraries for fast reactors

    CERN Document Server

    Ohki, S

    2003-01-01

    Japan Nuclear Cycle Development Institute (JNC) is considering the highly burnt fuel as well as the recycling of minor actinide (MA) in the development of commercialized fast reactor cycle systems. Higher accuracy in burnup calculation is going to be required for higher mass plutonium isotopes ( sup 2 sup 4 sup 0 Pu, etc.) and MA nuclides. In the framework of research and development aiming at the validation and necessary improvements of fast reactor burnup calculation, we investigated the differences among the burnup calculation results with the major nuclear data libraries: JEF-2.2, ENDF/B-VI Release 5, JENDL-3.2, and JENDL-3.3. We focused on the heavy metal nuclides such as plutonium and MA in the central core region of a conventional sodium-cooled fast reactor. For main heavy metal nuclides ( sup 2 sup 3 sup 5 U, sup 2 sup 3 sup 8 U, sup 2 sup 3 sup 9 Pu, sup 2 sup 4 sup 0 Pu, and sup 2 sup 4 sup 1 Pu), number densities after 1-cycle burnup did not change over one or two percent. Library dependence was re...

  5. Quantification of the computational accuracy of code systems on the burn-up credit using experimental re-calculations; Quantifizierung der Rechengenauigkeit von Codesystemen zum Abbrandkredit durch Experimentnachrechnungen

    Energy Technology Data Exchange (ETDEWEB)

    Behler, Matthias; Hannstein, Volker; Kilger, Robert; Moser, Franz-Eberhard; Pfeiffer, Arndt; Stuke, Maik

    2014-06-15

    In order to account for the reactivity-reducing effect of burn-up in the criticality safety analysis for systems with irradiated nuclear fuel (''burnup credit''), numerical methods to determine the enrichment and burnup dependent nuclide inventory (''burnup code'') and its resulting multiplication factor k{sub eff} (''criticality code'') are applied. To allow for reliable conclusions, for both calculation systems the systematic deviations of the calculation results from the respective true values, the bias and its uncertainty, are being quantified by calculation and analysis of a sufficient number of suitable experiments. This quantification is specific for the application case under scope and is also called validation. GRS has developed a methodology to validate a calculation system for the application of burnup credit in the criticality safety analysis for irradiated fuel assemblies from pressurized water reactors. This methodology was demonstrated by applying the GRS home-built KENOREST burnup code and the criticality calculation sequence CSAS5 from SCALE code package. It comprises a bounding approach and alternatively a stochastic, which both have been exemplarily demonstrated by use of a generic spent fuel pool rack and a generic dry storage cask, respectively. Based on publicly available post irradiation examination and criticality experiments, currently the isotopes of uranium and plutonium elements can be regarded for.

  6. Burn-up credit in criticality safety of PWR spent fuel

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoud, Rowayda F., E-mail: Rowayda_mahmoud@yahoo.com [Metallurgy Department, Nuclear Research Center, Atomic Energy Authority (Egypt); Shaat, Mohamed K. [Nuclear Engineering, Reactors Department, Nuclear Research Center, Atomic Energy Authority (Egypt); Nagy, M.E.; Agamy, S.A. [Professor of Nuclear Engineering, Nuclear and Radiation Department, Alexandria University (Egypt); Abdelrahman, Adel A. [Metallurgy Department, Nuclear Research Center, Atomic Energy Authority (Egypt)

    2014-12-15

    Highlights: • Designing spent fuel wet storage using WIMS-5D and MCNP-5 code. • Studying fresh and burned fuel with/out absorber like “B{sub 4}C and Ag–In–Cd” in racks. • Sub-criticality was confirmed for fresh and burned fuel under specific cases. • Studies for BU credit recommend increasing fuel burn-up to 60.0 GWD/MTU. • Those studies require new core structure materials, fuel composition and cladding. - Abstract: The criticality safety calculations were performed for a proposed design of a wet spent fuel storage pool. This pool will be used for the storage of spent fuel discharged from a typical pressurized water reactor (PWR). The mathematical model based on the international validated codes, WIMS-5 and MCNP-5 were used for calculating the effective multiplication factor, k{sub eff}, for the spent fuel stored in the pool. The data library for the multi-group neutron microscopic cross-sections was used for the cell calculations. The k{sub eff} was calculated for several changes in water density, water level, assembly pitch and burn-up with different initial fuel enrichment and new types and amounts of fixed absorbers. Also, k{sub eff} was calculated for the conservative fresh fuel case. The results of the calculations confirmed that the effective multiplication factor for the spent fuel storage is sub-critical for all normal and abnormal states. The future strategy for the burn-up credit recommends increasing the fuel burn-up to a value >60.0 GWD/MTU, which requires new fuel composition and new fuel cladding material with the assessment of the effects of negative reactivity build up.

  7. Influence of FIMA burnup on actinides concentrations in PWR reactors

    Directory of Open Access Journals (Sweden)

    Oettingen Mikołaj

    2016-01-01

    Full Text Available In the paper we present the study on the dependence of actinides concentrations in the spent nuclear fuel on FIMA burnup. The concentrations of uranium, plutonium, americium and curium isotopes obtained in numerical simulation are compared with the result of the post irradiation assay of two spent fuel samples. The samples were cut from the fuel rod irradiated during two reactor cycles in the Japanese Ohi-2 Pressurized Water Reactor. The performed comparative analysis assesses the reliability of the developed numerical set-up, especially in terms of the system normalization to the measured FIMA burnup. The numerical simulations were preformed using the burnup and radiation transport mode of the Monte Carlo Continuous Energy Burnup Code – MCB, developed at the Department of Nuclear Energy, Faculty of Energy and Fuels of AGH University of Science and Technology.

  8. A guide introducing burnup credit, preliminary version. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    It is examined to take burnup credit into account for criticality safety control of facility treating spent fuel. This work is a collection of current technical status of predicting isotopic composition and criticality of spent fuel, points to be specially considered for safety evaluation, and current status of legal affairs for the purpose of applying burnup credit to the criticality safety evaluation of the facility treating spent fuel in Japan. (author)

  9. The removal of reactive dyes using high-ash char

    Directory of Open Access Journals (Sweden)

    Moreira R.F.P.M.

    2001-01-01

    Full Text Available The thermodynamics and kinetics of adsorption of reactive dyes on high-ash char was studied. Equilibrium data were obtained using the static method with controlled agitation at temperatures in the range of 30 to 60ºC. The Langmuir isotherm model was used to describe the equilibrium of adsorption, and the equilibrium parameters, R L, in the range of 0 to 1 indicate favorable adsorption. The amount of dye adsorbed increased as temperature increased from 30 to 40ºC, but above 40ºC the increase in temperature resulted in a decrease in the amount of dye adsorbed. The kinetic data presented are for controlled agitation at 50 rpm and constant temperature with dye concentrations in the range of 10 ppm to50 ppm. The film mass transfer coefficient, Kf, and the effective diffusivity inside the particle, De, were fitted to the experimental data. The results indicate that internal diffusion governs the adsorption rate.

  10. Highly reactive free radicals in electronic cigarette aerosols.

    Science.gov (United States)

    Goel, Reema; Durand, Erwann; Trushin, Neil; Prokopczyk, Bogdan; Foulds, Jonathan; Elias, Ryan J; Richie, John P

    2015-09-21

    Electronic cigarette (EC) usage has increased exponentially, but limited data are available on its potential harmful effects. We tested for the presence of reactive, short-lived free radicals in EC aerosols by electron paramagnetic resonance spectroscopy (EPR) using the spin-trap phenyl-N-tert-butylnitrone (PBN). Radicals were detected in aerosols from all ECs and eliquids tested (2.5 × 10(13) to 10.3 × 10(13) radicals per puff at 3.3 V) and from eliquid solvents propylene glycol and glycerol and from "dry puffing". These results demonstrate, for the first time, the production of highly oxidizing free radicals from ECs which may present a potential toxicological risk to EC users.

  11. Experience with incomplete control rod insertion in fuel with burnup exceeding approximately 40 GWD/MTU

    Energy Technology Data Exchange (ETDEWEB)

    Kee, E. [Houston Lighting & Power Co., Wadworth, TX (United States)

    1997-01-01

    Analysis and measurement experience with fuel assemblies having incomplete control rod insertion at burnups of approximately 40 GWD/MTU is presented. Control rod motion dynamics and simplified structural analyses are presented and compared to measurement data. Fuel assembly growth measurements taken with the plant Refueling Machine Z-Tape are described and presented. Bow measurements (including plug gauging) are described and potential improvements are suggested. The measurements described and analysis performed show that sufficient guide tube bow (either from creep or yield buckling) is present in some high burnup assemblies to stop the control rods before they reach their full limit of travel. Recommendations are made that, if implemented, could improve cost performance related to testing and analysis activities.

  12. Development of highly reactive mono-(meth)acrylates as reactive diluents for dimethacrylate-based dental resin systems.

    Science.gov (United States)

    Lu, Hui; Stansbury, Jeffrey W; Nie, Jun; Berchtold, Kathryn A; Bowman, Christopher N

    2005-04-01

    Reactive diluents such as triethyleneglycol-dimethacrylate (TEGDMA) have been widely used with bisphenol-A-glycidyl-dimethacrylate (Bis-GMA) to achieve restorative resins with appropriate viscosity and higher conversion. However, additional water sorption and polymerization shrinkage were also introduced. The aim of this work is to investigate whether the cure and material properties can be improved in dental resins containing novel mono-(meth)acrylates as reactive diluents so that these Bis-GMA-based copolymers have reduced polymerization shrinkage but higher overall double bond conversion. Several ultra-high-reactivity mono-(meth)acrylates that contain secondary functionalities have been synthesized and investigated. The polymerization rate and double bond conversion were monitored using photo-FTIR. Polymerization shrinkage, dynamic mechanical analysis, and flexural strength were characterized. Compared with the Bis-GMA/TEGDMA control, the Bis-GMA/mono-methacrylate systems studied showed higher final conversions, faster curing rates, and decreased polymerization shrinkage. Our optimum system Bis-GMA/morpholine carbamate methacrylate achieved 86% final conversion (vs. 65%), a polymerization rate 3.5 times faster, and a 30% reduction in polymerization volumetric shrinkage. These results indicate that certain highly reactive, novel mono-(meth)acrylates possess very promising potential to replace TEGDMA as reactive diluents and can readily be applied to develop superior dental resins.

  13. Monte Carlo calculations of the REBUS critical experiment for validation of burn-up credit

    Energy Technology Data Exchange (ETDEWEB)

    Hennebach, M.; Kuhl, H. [WTI GmbH, Julich (Germany)

    2008-07-01

    The REBUS experiment is a valuable benchmark for the validation of Monte Carlo criticality codes within the context of burn-up credit. It investigates the difference in reactivity worth of unirradiated fuel rods and of fuel rods irradiated in a PWR. This paper presents results of criticality calculations for this experiment with the Monte Carlo codes MCNP and SCALE/KENO. The results show that even the comparatively small reactivity loss of about 2000 pcm measured in this experiment can be calculated within an accuracy of 6 per cent. A detailed comparison of measured and calculated core characteristics (fission rate and flux distributions) shows good agreement, which indicates an adequately detailed model geometry for criticality calculations. The slight underestimation (500 pcm) of absolute k(eff) values is not out of the typical range for criticality benchmark experiments.

  14. Fuel Behaviour at High During RIA and LOCA Accidents; Comportamiento del Combustible de Alto Quemado en Accidents RIA y LOCA

    Energy Technology Data Exchange (ETDEWEB)

    Barrio del Juanes, M.T.; Garcia Cuesta, J.C.; Vallejo Diaz, I.; Herranz Puebla

    2001-07-01

    Safety analysis of high burnup fuel requires ensuring the acceptable performance under design basis accidents, in particular during conditions representative of Reactivity Accidents (RIA) and Loss-of-Coolant Accidents (LOCA). The report's objective is to compile the state of the art on these issues. This is mainly focused in the effort made to define the applicability of safety criteria to the high burnup fuel. Irradiation damage modifies fuel rod properties, thus the probability of fuel to withstand thermal and mechanical loads during an accident could be quite different compared with unirradiated fuel. From the thermal point of view, fuel conductivity is the most affected property, decreasing notably with irradiation. From the mechanical point of view, a change in the pellet microstructure at its periphery is observed at high burnup (remiffect). Cladding is also effected during operation, showing a significant external and internal corrosion. All these phenomena result in the decrease of efficiency in heat transfer an in the reduction of capability to accommodate mechanical loads; this situation is especially significant at high burnup, when pellet-cladding mechanical interaction is present. Knowledge about these phenomena is not possible without appropriate experimental programmes. The most relevant have been performed in France, Japan, United States and Russia. Results obtained with fuel at high burnup show significant differences with respect to the phenomena observed in fuel at the present discharge burnup. Indeed, this is the encouragement to research about this occurrence. This study is framed within the CSN-CIEMAT agreement, about Fuel Thermo-Mechanical Behaviour at High Burnup. (Author) 172 refs.

  15. Cerebrovascular reactivity alterations in asymptomatic high school football players.

    Science.gov (United States)

    Svaldi, Diana O; Joshi, Chetas; Robinson, Meghan E; Shenk, Trey E; Abbas, Kausar; Nauman, Eric A; Leverenz, Larry J; Talavage, Thomas M

    2015-01-01

    Cerebrovascular reactivity (CVR) is impaired following brain injury, increasing susceptibility to subsequent injury. CVR was tracked in football and non-collision athletes throughout one season. CVR transiently decreased in football athletes during the first half of the season. Results indicate the brain adapts slowly to increases in loading, increasing risk for injury.

  16. Peer Relations and Peer Deviance as Predictors of Reactive and Proactive Aggression among High School Girls

    Science.gov (United States)

    Uz Bas, Asli; Öz Soysal, Fatma Selda

    2016-01-01

    This study aimed to investigate associations between reactive and proactive aggression and peer relations and peer deviance among high school girls. A total of 442 high school students participated in this study. Reactive-Proactive Aggression Questionnaire, the Peer Relations Scale, and the Peer Deviance Scale were used to collect data. Results…

  17. High throughput assay for evaluation of reactive carbonyl scavenging capacity

    Directory of Open Access Journals (Sweden)

    N. Vidal

    2014-01-01

    Full Text Available Many carbonyl species from either lipid peroxidation or glycoxidation are extremely reactive and can disrupt the function of proteins and enzymes. 4-hydroxynonenal and methylglyoxal are the most abundant and toxic lipid-derived reactive carbonyl species. The presence of these toxics leads to carbonyl stress and cause a significant amount of macromolecular damages in several diseases. Much evidence indicates trapping of reactive carbonyl intermediates may be a useful strategy for inhibiting or decreasing carbonyl stress-associated pathologies. There is no rapid and convenient analytical method available for the assessment of direct carbonyl scavenging capacity, and a very limited number of carbonyl scavengers have been identified to date, their therapeutic potential being highlighted only recently. In this context, we have developed a new and rapid sensitive fluorimetric method for the assessment of reactive carbonyl scavengers without involvement glycoxidation systems. Efficacy of various thiol- and non-thiol-carbonyl scavenger pharmacophores was tested both using this screening assay adapted to 96-well microplates and in cultured cells. The scavenging effects on the formation of Advanced Glycation End-product of Bovine Serum Albumin formed with methylglyoxal, 4-hydroxynonenal and glucose-glycated as molecular models were also examined. Low molecular mass thiols with an α-amino-β-mercaptoethane structure showed the highest degree of inhibitory activity toward both α,β-unsaturated aldehydes and dicarbonyls. Cysteine and cysteamine have the best scavenging ability toward methylglyoxal. WR-1065 which is currently approved for clinical use as a protective agent against radiation and renal toxicity was identified as the best inhibitor of 4-hydroxynonenal.

  18. Automated system for determining the burnup of spent nuclear fuel

    Directory of Open Access Journals (Sweden)

    Mokritskii V. A.

    2014-12-01

    Full Text Available The authors analyze their experience in application of semi-conductor detectors and development of a breadboard model of the monitoring system for spent nuclear fuel (SNF. Such system should use CdZnTe-detectors in which one-charging gathering conditions are realized. The proposed technique of real time SNF control during reloading technological operations is based on the obtained research results. Methods for determining the burnup of spent nuclear fuel based on measuring the characteristics of intrinsic radiation are covered in many papers, but those metods do not usually take into account that the nuclear fuel used during the operation has varying degrees of initial enrichment, or a new kind of fuel may be used. Besides, the known methods often do not fit well into the existing technology of fuel loading operations and are not suitable for operational control. Nuclear fuel monitoring (including burnup determination system in this research is based on the measurement of the spectrum of natural gamma-radiation of irradiated fuel assemblies (IFA, as from the point of view of minimizing the time spent, the measurement of IFA gamma spectra directly during fuel loading is optimal. It is the overload time that is regulated rather strictly, and burnup control operations should be coordinated with the schedule of the fuel loading. Therefore, the real time working capacity of the system should be chosen as the basic criterion when constructing the structure of such burnup control systems.

  19. Assessment of Fission Product Cross-Section Data for Burnup Credit Applications

    Energy Technology Data Exchange (ETDEWEB)

    Leal, Luiz C [ORNL; Derrien, Herve [ORNL; Dunn, Michael E [ORNL; Mueller, Don [ORNL

    2007-12-01

    Past efforts by the Department of Energy (DOE), the Electric Power Research Institute (EPRI), the Nuclear Regulatory Commission (NRC), and others have provided sufficient technical information to enable the NRC to issue regulatory guidance for implementation of pressurized-water reactor (PWR) burnup credit; however, consideration of only the reactivity change due to the major actinides is recommended in the guidance. Moreover, DOE, NRC, and EPRI have noted the need for additional scientific and technical data to justify expanding PWR burnup credit to include fission product (FP) nuclides and enable burnup credit implementation for boiling-water reactor (BWR) spent nuclear fuel (SNF). The criticality safety assessment needed for burnup credit applications will utilize computational analyses of packages containing SNF with FP nuclides. Over the years, significant efforts have been devoted to the nuclear data evaluation of major isotopes pertinent to reactor applications (i.e., uranium, plutonium, etc.); however, efforts to evaluate FP cross-section data in the resonance region have been less thorough relative to actinide data. In particular, resonance region cross-section measurements with corresponding R-matrix resonance analyses have not been performed for FP nuclides. Therefore, the objective of this work is to assess the status and performance of existing FP cross-section and cross-section uncertainty data in the resonance region for use in burnup credit analyses. Recommendations for new cross-section measurements and/or evaluations are made based on the data assessment. The assessment focuses on seven primary FP isotopes (103Rh, 133Cs, 143Nd, 149Sm, 151Sm, 152Sm, and 155Gd) that impact reactivity analyses of transportation packages and two FP isotopes (153Eu and 155Eu) that impact prediction of 155Gd concentrations. Much of the assessment work was completed in 2005, and the assessment focused on the latest FP cross-section evaluations available in the

  20. Coolant Density and Control Blade History Effects in Extended BWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [ORNL; Marshall, William BJ J [ORNL; Bowman, Stephen M [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Martinez-Gonzalez, Jesus S [ORNL

    2015-01-01

    Oak Ridge National Laboratory and the US Nuclear Regulatory Commission have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase investigates the applicability of peak reactivity methods currently used for spent fuel pools to spent fuel storage and transportation casks and the validation of reactivity (keff) calculations and predicted spent fuel compositions. The second phase focuses on extending BUC beyond peak reactivity. This paper documents work performed to date investigating some aspects of extended BUC. (The technical basis for application of peak reactivity methods to BWR fuel in storage and transportation systems is presented in a companion paper.) Two reactor operating parameters are being evaluated to establish an adequate basis for extended BWR BUC: (1) the effect of axial void profile and (2) the effect of control blade utilization during operation. A detailed analysis of core simulator data for one cycle of a modern operating BWR plant was performed to determine the range of void profiles and the variability of the profile experienced during irradiation. Although a single cycle does not provide complete data, the data obtained are sufficient to determine the primary effects and to identify conservative modeling approaches. These data were used in a study of the effect of axial void profile. The first stage of the study was determination of the necessary moderator density temporal fidelity in depletion modeling. After the required temporal fidelity was established, multiple void profiles were used to examine the effect on cask reactivity. The results of these studies are being used to develop recommendations for conservatively modeling the void profile effects for BWR depletion calculations. The second operational parameter studied was control blade history. Control blades are inserted in

  1. Extended Burnup Credit for BWR Spent Nuclear Fuel in Storage and Transportation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ade, Brian J [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bowman, Stephen M [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gauld, Ian C [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ilas, Germina [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Martinez, J. S. [Univ. Politecnica de Madrid (Spain). Dept. of Nuclear Engineering

    2015-01-01

    [Full Text] Oak Ridge National Laboratory and the United States Nuclear Regulatory Commission have initiated a multiyear project to investigate the application of burnup credit (BUC) for boiling-water reactor (BWR) fuel in storage and transportation casks. This project includes two phases. The first phase investigates the applicability of peak reactivity methods currently used for spent fuel pools to spent fuel storage and transportation casks and the validation of reactivity (keff) calculations and depleted fuel compositions. The second phase focuses on extending BUC beyond peak reactivity. This paper documents work performed to date, investigating some aspects of extended BUC, and it also describes the plan to complete the evaluations. The technical basis for application of peak reactivity methods to BWR fuel in storage and transportation systems is presented in a companion paper. Two reactor operating parameters are being evaluated to establish an adequate basis for extended BWR BUC, including investigation of the axial void profile effect and the effect of control blade utilization during operation. A detailed analysis of core simulator data for one cycle of an operating BWR plant was performed to determine the range of void profiles and the variability of the profile experienced during irradiation. While a single cycle does not provide complete data, the data obtained are sufficient to use to determine the primary effects and identify conservative modeling approaches. Using data resulting from a single cycle, the axial void profile is studied by first determining the temporal fidelity necessary in depletion modeling, and then using multiple void profiles to examine the effect of the void profile on cask reactivity. The results of these studies are being used to develop recommendations for conservatively modeling the void profile effects for BWR depletion calculations. The second operational parameter studied is control blade exposure. Control blades

  2. Data Mining Techniques to Estimate Plutonium, Initial Enrichment, Burnup, and Cooling Time in Spent Fuel Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Trellue, Holly Renee [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Fugate, Michael Lynn [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Tobin, Stephen Joesph [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-03-19

    The Next Generation Safeguards Initiative (NGSI), Office of Nonproliferation and Arms Control (NPAC), National Nuclear Security Administration (NNSA) of the U.S. Department of Energy (DOE) has sponsored a multi-laboratory, university, international partner collaboration to (1) detect replaced or missing pins from spent fuel assemblies (SFA) to confirm item integrity and deter diversion, (2) determine plutonium mass and related plutonium and uranium fissile mass parameters in SFAs, and (3) verify initial enrichment (IE), burnup (BU), and cooling time (CT) of facility declaration for SFAs. A wide variety of nondestructive assay (NDA) techniques were researched to achieve these goals [Veal, 2010 and Humphrey, 2012]. In addition, the project includes two related activities with facility-specific benefits: (1) determination of heat content and (2) determination of reactivity (multiplication). In this research, a subset of 11 integrated NDA techniques was researched using data mining solutions at Los Alamos National Laboratory (LANL) for their ability to achieve the above goals.

  3. Short ragweeds is highly cross-reactive with other ragweeds.

    Science.gov (United States)

    Christensen, Lars H; Ipsen, Henrik; Nolte, Hendrik; Maloney, Jennifer; Nelson, Harold S; Weber, Richard; Lund, Kaare

    2015-12-01

    The most widespread ragweed (Ambrosia) species in North America are short ragweed (Ambrosia artemisiifolia; Amb a), giant ragweed (Ambrosia trifida; Amb t), and western ragweed (Ambrosia psilostachya; Amb p). Varied geographic distributions of ragweed species raise questions regarding the need for ragweed species-specific allergen immunotherapy. To determine allergenic cross-reactivity among ragweed species by immunologic analyses of sera from subjects allergic to ragweed from North America and Europe. Sera were collected from 452 subjects allergic to ragweed who participated in Amb a sublingual immunotherapy tablet clinical trials. All subjects had positive skin prick test and serum IgE against Amb a. Ragweed-specific IgE (pre treatment) and IgG4 (post treatment) were measured by ImmunoCAP. IgE inhibition studies among Amb a, Amb t, and Amb p were conducted. Using pooled sera from another ragweed-allergic population, IgE inhibition studies of 7 less widespread Ambrosia species also were conducted. A strong correlation between Amb a vs Amb p and Amb t serum IgE levels was observed. In the vast majority of pretreatment sera, Amb a inhibited Amb a, Amb p, and Amb t IgE reactivity by more than 90%. Strong correlations were observed between Amb a vs Amb p and Amb t post-treatment IgG4 levels. In pooled sera, Amb a extract inhibited the binding of serum IgE to all 10 ragweed species by 98%-100%. In a population of subjects allergic to Amb a, substantial allergenic cross-reactivity among Amb a, Amb p, and Amb t was demonstrated. These in vitro data suggest that an Amb a-based single-species ragweed allergen immunotherapy may be therapeutically active in patients exposed to diverse ragweed pollens. Clinicaltrials.gov, NCT00770315, NCT00783198, and NCT00330083. Copyright © 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  4. Photoinduced reactivity of liquid ethanol at high pressure.

    Science.gov (United States)

    Ceppatelli, Matteo; Fanetti, Samuele; Citroni, Margherita; Bini, Roberto

    2010-12-02

    The room temperature photoinduced reactivity of liquid ethanol has been studied as a function of pressure up to 1.5 GPa by means of a diamond anvil cell. Exploiting the dissociative character of the lowest electronic excited states, reached through two-photon absorption of near-UV photons (350 nm), irreversible reactive processes have been triggered in the pure system. The active species are radicals forming along two main dissociation channels involving the split of C-O and O-H bonds. The characterization of the reaction products has been performed by in situ FTIR and Raman spectroscopy. At pressures of a few megapascals, molecular hydrogen is the main reaction product, an important issue in the framework of environmentally friendly synthesis of this energetic vector. In the gigapascal range, the main products are ethane, 2-butanol, 2,3-butanediol, 1,1-diethoxyethane, and some carbonylic compounds. The relative amount of these species changes with pressure reflecting the nature of the radicals formed in the photodissociation process. As the pressure increases, the processes requiring a greater molecularity are favored, whereas those requiring internal rearrangements are inhibited. Disproportion products like CH(4), H(2)O, and CO(2) increase when the amount of ethanol decreases due to the reaction, becoming the main products only when ethanol is exhausted.

  5. HIGH PREVALENCE OF REACTIVE ARTHRITIS IN RUSSIA: OVERDIAGNOSIS OR REALITY?

    Directory of Open Access Journals (Sweden)

    R. M. Balabanova

    2015-01-01

    Full Text Available Reactive arthritis (ReA is one of the types of spondyloarthritis. According to the statistics reports by the Ministry of Health of Russia, the prevalence of ReA in 2013 was 42.8 per 100,000 adult population, 99, and 172.4 per 100,000 children aged 0–14 and 15–17 years, respectively. There is a wide scatter of ReA detection rates in both the federal districts and subjects of the Russian Federation, which may be associated with both the spread of sexually transmitted infections, asymptomatic trigger Chlamydia infection, and overdiagnosis of ReA.

  6. Combustion Mode Design with High Efficiency and Low Emissions Controlled by Mixtures Stratification and Fuel Reactivity

    Directory of Open Access Journals (Sweden)

    Hu eWang

    2015-08-01

    Full Text Available This paper presents a review on the combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixture stratification that have been conducted in the authors’ group, including the charge reactivity controlled homogeneous charge compression ignition (HCCI combustion, stratification controlled premixed charge compression ignition (PCCI combustion, and dual-fuel combustion concepts controlled by both fuel reactivity and mixture stratification. The review starts with the charge reactivity controlled HCCI combustion, and the works on HCCI fuelled with both high cetane number fuels, such as DME and n-heptane, and high octane number fuels, such as methanol, natural gas, gasoline and mixtures of gasoline/alcohols, are reviewed and discussed. Since single fuel cannot meet the reactivity requirements under different loads to control the combustion process, the studies related to concentration stratification and dual-fuel charge reactivity controlled HCCI combustion are then presented, which have been shown to have the potential to achieve effective combustion control. The efforts of using both mixture and thermal stratifications to achieve the auto-ignition and combustion control are also discussed. Thereafter, both charge reactivity and mixture stratification are then applied to control the combustion process. The potential and capability of thermal-atmosphere controlled compound combustion mode and dual-fuel reactivity controlled compression ignition (RCCI/highly premixed charge combustion (HPCC mode to achieve clean and high efficiency combustion are then presented and discussed. Based on these results and discussions, combustion mode design with high efficiency and low emissions controlled by fuel reactivity and mixtures stratification in the whole operating range is proposed.

  7. Estimating NIRR-1 burn-up and core life time expectancy using the codes WIMS and CITATION

    Science.gov (United States)

    Yahaya, B.; Ahmed, Y. A.; Balogun, G. I.; Agbo, S. A.

    The Nigeria Research Reactor-1 (NIRR-1) is a low power miniature neutron source reactor (MNSR) located at the Centre for Energy Research and Training, Ahmadu Bello University, Zaria Nigeria. The reactor went critical with initial core excess reactivity of 3.77 mk. The NIRR-1 cold excess reactivity measured at the time of commissioning was determined to be 4.97 mk, which is more than the licensed range of 3.5-4 mk. Hence some cadmium poison worth -1.2 mk was inserted into one of the inner irradiation sites which act as reactivity regulating device in order to reduce the core excess reactivity to 3.77 mk, which is within recommended licensed range of 3.5 mk and 4.0 mk. In this present study, the burn-up calculations of the NIRR-1 fuel and the estimation of the core life time expectancy after 10 years (the reactor core expected cycle) have been conducted using the codes WIMS and CITATION. The burn-up analyses carried out indicated that the excess reactivity of NIRR-1 follows a linear decreasing trend having 216 Effective Full Power Days (EFPD) operations. The reactivity worth of top beryllium shim data plates was calculated to be 19.072 mk. The result of depletion analysis for NIRR-1 core shows that (7.9947 ± 0.0008) g of U-235 was consumed for the period of 12 years of operating time. The production of the build-up of Pu-239 was found to be (0.0347 ± 0.0043) g. The core life time estimated in this research was found to be 30.33 years. This is in good agreement with the literature

  8. High Transparent Conductive Aluminum-Doped Zinc Oxide Thin Films by Reactive Co-Sputtering (Postprint)

    Science.gov (United States)

    2016-03-30

    AFRL-RX-WP-JA-2017-0144 HIGH TRANSPARENT CONDUCTIVE ALUMINUM- DOPED ZINC OXIDE THIN FILMS BY REACTIVE CO- SPUTTERING (POSTPRINT...TRANSPARENT CONDUCTIVE ALUMINUM-DOPED ZINC OXIDE THIN FILMS BY REACTIVE CO-SPUTTERING (POSTPRINT) 5a. CONTRACT NUMBER FA8650-16-D-5402-0001 5b. GRANT...ANSI Std. Z39-18 TD.11.pdf Optical Interference Coatings (OIC) 2016 © OSA 2016 1 High Transparent Conductive Aluminum-doped Zinc Oxide Thin

  9. SENSITIVITY AND UNCERTAINTY ANALYSIS OF COMMERCIAL REACTOR CRITICALS FOR BURNUP CREDIT

    Energy Technology Data Exchange (ETDEWEB)

    Radulescu, Georgeta [ORNL; Mueller, Don [ORNL; Wagner, John C [ORNL

    2009-01-01

    The purpose of this study is to provide insights into the neutronic similarities that may exist between a generic cask containing typical spent nuclear fuel assemblies and commercial reactor critical (CRC) state-points. Forty CRC state-points from five pressurized-water reactors were selected for the study and the type of CRC state-points that may be applicable for validation of burnup credit criticality safety calculations for spent fuel transport/storage/disposal systems are identified. The study employed cross-section sensitivity and uncertainty analysis methods developed at Oak Ridge National Laboratory and the TSUNAMI set of tools in the SCALE code system as a means to investigate system similarity on an integral and nuclide-reaction specific level. The results indicate that, except for the fresh fuel core configuration, all analyzed CRC state-points are either highly similar, similar, or marginally similar to a generic cask containing spent nuclear fuel assemblies with burnups ranging from 10 to 60 GWd/MTU. Based on the integral system parameter, C{sub k}, approximately 30 of the 40 CRC state-points are applicable to validation of burnup credit in the generic cask containing typical spent fuel assemblies with burnups ranging from 10 to 60 GWd/MTU. The state-points providing the highest similarity (C{sub k} > 0.95) were attained at or near the end of a reactor cycle. The C{sub k} values are dominated by neutron reactions with major actinides and hydrogen, as the sensitivities of these reactions are much higher than those of the minor actinides and fission products. On a nuclide-reaction specific level, the CRC state-points provide significant similarity for most of the actinides and fission products relevant to burnup credit. A comparison of energy-dependent sensitivity profiles shows a slight shift of the CRC K{sub eff} sensitivity profiles toward higher energies in the thermal region as compared to the K{sub eff} sensitivity profile of the generic cask

  10. Burnup calculations using serpent code in accelerator driven thorium reactors

    Energy Technology Data Exchange (ETDEWEB)

    Korkmaz, M.E.; Agar, O. [Karamanoglu Mehmetbey Univ., Karaman (Turkey). Physics Dept.; Yigit, M. [Aksaray Univ. (Turkey). Physics Dept.

    2013-07-15

    In this study, burnup calculations have been performed for a sodium cooled Accelerator Driven Thorium Reactor (ADTR) using the Serpent 1.1.16 Monte Carlo code. The ADTR has been designed for burning minor actinides, mixed {sup 232}Th and mixed {sup 233}U fuels. A solid Pb-Bi spallation target in the center of the core is used and sodium as coolant. The system is designed for a heating power of 2 000 MW and for an operation time of 600 days. For burnup calculations the Advanced Matrix Exponential Method CRAM (Chebyshev Rational Approximation Method) and different nuclear data libraries (ENDF7, JEF2.2, JEFF3.1.1) were used. The effective multiplication factor change from 0.93 to 0.97 for different nuclear data libraries during the reactor operation period. (orig.)

  11. New burnup calculation of TRIGA IPR-R1 reactor

    Energy Technology Data Exchange (ETDEWEB)

    Meireles, Sincler P. de; Campolina, Daniel de A.M.; Santos, Andre A. Campagnole dos; Menezes, Maria A.B.C.; Mesquita, Amir Z., E-mail: sinclercdtn@hotmail.com.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2015-07-01

    The IPR-R1 TRIGA Mark I research reactor, located at the Nuclear Technology Development Center - CDTN, Belo Horizonte, Brazil, operates since 1960.The reactor is operating for more than fifty years and has a long history of operation. Determining the current composition of the fuel is very important to calculate various parameters. The reactor burnup calculation has been performed before, however, new techniques, methods, software and increase of the processing capacity of the new computers motivates new investigations to be performed. This work presents the evolution of effective multiplication constant and the results of burnup. This new model has a more detailed geometry with the introduction of the new devices, like the control rods and the samarium discs. This increase of materials in the simulation in burnup calculation was very important for results. For these series of simulations a more recently cross section library, ENDF/B-VII, was used. To perform the calculations two Monte Carlo particle transport code were used: Serpent and MCNPX. The results obtained from two codes are presented and compared with previous studies in the literature. (author)

  12. Static reactive power compensators for high-voltage power systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1981-04-01

    A study conducted to summarize the role of static reactive power compensators for high voltage power system applications is described. This information should be useful to the utility system planning engineer in applying static var systems (SVS) to high voltage as (HVAC) systems. The static var system is defined as a form of reactive power compensator. The general need for reactive power compensation in HVAC systems is discussed, and the static var system is compared to other devices utilized to provide reactive power compensation. Examples are presented of applying SVS for specific functions, such as the prevention of voltage collapse. The operating principles of commercially available SVS's are discussed in detail. The perormance and active power loss characteristics of SVS types are compared.

  13. Burnup Credit Approach Used in the Yucca Mountain License Application

    Energy Technology Data Exchange (ETDEWEB)

    Scaglione, John M [ORNL; Wagner, John C [ORNL

    2010-01-01

    The United States Department of Energy has submitted a license application (LA) for construction authorization of a deep geologic repository at Yucca Mountain, Nevada. The license application is currently under review by the United States Nuclear Regulatory Commission (NRC). This paper will describe the methodology and approach used in the LA to address the issue of criticality and the role of burnup credit during the postclosure period. The most significant and effective measures for prevention of criticality in the repository include multiple redundant barriers that act to isolate fissionable material from water (which can act as a moderator, corrosive agent, and transporter of fissile material); inherent geometry of waste package internals and waste forms; presence of fixed neutron absorbers in waste package internals; and fuel burnup for commercial spent nuclear fuel. A probabilistic approach has been used to screen criticality from the total system performance assessment. Within the probabilistic approach, criticality is considered an event, and the total probability of a criticality event occurring within 10,000 years of disposal is calculated and compared against the regulatory criterion. The total probability of criticality includes contributions associated with both internal (within waste packages) and external (external to waste packages) criticality for each of the initiating events that could lead to waste package breach. The occurrence of and conditions necessary for criticality in the repository have been thoroughly evaluated using a comprehensive range of parameter distributions. A simplified design-basis modeling approach has been used to evaluate the probability of criticality by using numerous significant and conservative assumptions. Burnup credit is used only for evaluations of in-package configurations and uses a combination of conservative and bounding modeling approximations to ensure conservatism. This paper will review the NRC regulatory

  14. Comparison of C-reactive protein and high-sensitivity C-reactive protein levels in patients on hemodialysis

    Directory of Open Access Journals (Sweden)

    Imed Helal

    2012-01-01

    Full Text Available Chronic inflammation is highly prevalent in patients on hemodialysis (HD, as evidenced by increased levels of C-reactive protein (CRP. We compared CRP to high-sensitivity C-reactive protein (hs-CRP to determine whether it has any clinical implications and prognostic significance in terms of mortality. CRP was measured using a standard immunoturbidometric assay on the COBAS; INTEGRA system and hs-CRP was measured using the Dade Behring on the Konelab Nephelometer in 50 patients on HD. CRP (≥6 mg/L and hs-CRP (≥3 mg/L levels were elevated in 30% and 54% of the patients, respectively. A significant correlation was noted between hs-CRP and CRP levels (r = 0.98, P <0.001. Deming regression analysis showed that the slope was near one (r = 0.90; 0.83-0.94 and that the intercept was small. Multivariate regression confirmed that age above 40 years (RR = 3.69, P = 0.027 and duration on HD greater than five years (RR = 3.71, P = 0.028 remained significant independent predictors of serum hs-CRP. Thirteen patients died during follow-up (26%. Multivariate Cox regression demonstrated that hs-CRP (RR = 1.062, P = 0.03 and CRP levels (RR = 1.057, P = 0.009 and age (RR = 1.078, P = 0.001 were the most powerful predictors of mortality. The CRP standard assay presents a reasonable alternative to the hs-CRP assay in patients on HD. The advantages of the CRP standard assay are its online and real-time availability as well as lower costs, particularly in developing countries.

  15. Lubricity and Tribochemical Reactivity of Advanced Materials Under High Vacuum

    Science.gov (United States)

    Igartua, A.; Berriozabal, E.; Zabala, B.; Pagano, F.; Minami, I.; Doerr, N.; Gabler, C.; Nevshupa, R.; Roman, E.; Pleth Nielsen, L.; Louring, S.; Muntada, L.

    2015-09-01

    The aim of this study was to develop and characterize advanced tribological materials for space applications. For this purpose a newly developed Ultra High Vacuum (UHV) tribometer CA3UHV was used to determine friction, wear and triboemission of gases and volatiles from atmospheric pressure down to high or ultrahigh vacuum. The study was focused on two classes of materials: a) advanced lubricants based on ionic liquids (ILs), b) engineered diamond-like carbon films as anti- wear and low-friction coatings. Tribochemical mechanisms were identified by analyzing gas triboemission involved in the generation of protective tribofilm layer and/or transfer film and surface chemical characterization.

  16. A feasibility and optimization study to determine cooling time and burnup of advanced test reactor fuels using a nondestructive technique

    Energy Technology Data Exchange (ETDEWEB)

    Navarro, Jorge [Univ. of Utah, Salt Lake City, UT (United States)

    2013-12-01

    The goal of this study presented is to determine the best available non-destructive technique necessary to collect validation data as well as to determine burn-up and cooling time of the fuel elements onsite at the Advanced Test Reactor (ATR) canal. This study makes a recommendation of the viability of implementing a permanent fuel scanning system at the ATR canal and leads3 to the full design of a permanent fuel scan system. The study consisted at first in determining if it was possible and which equipment was necessary to collect useful spectra from ATR fuel elements at the canal adjacent to the reactor. Once it was establish that useful spectra can be obtained at the ATR canal the next step was to determine which detector and which configuration was better suited to predict burnup and cooling time of fuel elements non-destructively. Three different detectors of High Purity Germanium (HPGe), Lanthanum Bromide (LaBr3), and High Pressure Xenon (HPXe) in two system configurations of above and below the water pool were used during the study. The data collected and analyzed was used to create burnup and cooling time calibration prediction curves for ATR fuel. The next stage of the study was to determine which of the three detectors tested was better suited for the permanent system. From spectra taken and the calibration curves obtained, it was determined that although the HPGe detector yielded better results, a detector that could better withstand the harsh environment of the ATR canal was needed. The in-situ nature of the measurements required a rugged fuel scanning system, low in maintenance and easy to control system. Based on the ATR canal feasibility measurements and calibration results it was determined that the LaBr3 detector was the best alternative for canal in-situ measurements; however in order to enhance the quality of the spectra collected using this scintillator a deconvolution method was developed. Following the development of the deconvolution method

  17. Engineered, highly reactive substrates of microbial transglutaminase enable protein labeling within various secondary structure elements.

    Science.gov (United States)

    Rachel, Natalie M; Quaglia, Daniela; Lévesque, Éric; Charette, André B; Pelletier, Joelle N

    2017-11-01

    Microbial transglutaminase (MTG) is a practical tool to enzymatically form isopeptide bonds between peptide or protein substrates. This natural approach to crosslinking the side-chains of reactive glutamine and lysine residues is solidly rooted in food and textile processing. More recently, MTG's tolerance for various primary amines in lieu of lysine have revealed its potential for site-specific protein labeling with aminated compounds, including fluorophores. Importantly, MTG can label glutamines at accessible positions in the body of a target protein, setting it apart from most labeling enzymes that react exclusively at protein termini. To expand its applicability as a labeling tool, we engineered the B1 domain of Protein G (GB1) to probe the selectivity and enhance the reactivity of MTG toward its glutamine substrate. We built a GB1 library where each variant contained a single glutamine at positions covering all secondary structure elements. The most reactive and selective variants displayed a >100-fold increase in incorporation of a recently developed aminated benzo[a]imidazo[2,1,5-cd]indolizine-type fluorophore, relative to native GB1. None of the variants were destabilized. Our results demonstrate that MTG can react readily with glutamines in α-helical, β-sheet, and unstructured loop elements and does not favor one type of secondary structure. Introducing point mutations within MTG's active site further increased reactivity toward the most reactive substrate variant, I6Q-GB1, enhancing MTG's capacity to fluorescently label an engineered, highly reactive glutamine substrate. This work demonstrates that MTG-reactive glutamines can be readily introduced into a protein domain for fluorescent labeling. © 2017 The Protein Society.

  18. Tutorial: Reactive high power impulse magnetron sputtering (R-HiPIMS)

    Science.gov (United States)

    Anders, André

    2017-05-01

    High Power Impulse Magnetron Sputtering (HiPIMS) is a coating technology that combines magnetron sputtering with pulsed power concepts. By applying power in pulses of high amplitude and a relatively low duty cycle, large fractions of sputtered atoms and near-target gases are ionized. In contrast to conventional magnetron sputtering, HiPIMS is characterized by self-sputtering or repeated gas recycling for high and low sputter yield materials, respectively, and both for most intermediate materials. The dense plasma in front of the target has the dual function of sustaining the discharge and providing plasma-assistance to film growth, affecting the microstructure of growing films. Many technologically interesting thin films are compound films, which are composed of one or more metals and a reactive gas, most often oxygen or nitrogen. When reactive gas is added, non-trivial consequences arise for the system because the target may become "poisoned," i.e., a compound layer forms on the target surface affecting the sputtering yield and the yield of secondary electron emission and thereby all other parameters. It is emphasized that the target state depends not only on the reactive gas' partial pressure (balanced via gas flow and pumping) but also on the ion flux to the target, which can be controlled by pulse parameters. This is a critical technological opportunity for reactive HiPIMS (R-HiPIMS). The scope of this tutorial is focused on plasma processes and mechanisms of operation and only briefly touches upon film properties. It introduces R-HiPIMS in a systematic, step-by-step approach by covering sputtering, magnetron sputtering, reactive magnetron sputtering, pulsed reactive magnetron sputtering, HiPIMS, and finally R-HiPIMS. The tutorial is concluded by considering variations of R-HiPIMS known as modulated pulsed power magnetron sputtering and deep-oscillation magnetron sputtering and combinations of R-HiPIMS with superimposed dc magnetron sputtering.

  19. Turbulent exchange of energy, momentum, and reactive gases between high vegetation and the atmospheric boundary layer

    NARCIS (Netherlands)

    Shapkalijevski, M.M.

    2017-01-01

    This thesis deals with the representation of the exchange of energy, momentum and chemically reactive compounds between the land, covered by high vegetation, and the lowest part of the atmosphere, named as atmospheric boundary layer (ABL). The study presented in this thesis introduces the roughness

  20. Breeding for high specific immune reactivity affects sensitivity to the environment

    NARCIS (Netherlands)

    Parmentier, H.K.; Verhofstad, L.P.M.; Vries Reilingh, de G.; Nieuwland, M.G.B.

    2012-01-01

    Lipopolysaccharides (LPS) are present in high levels in the air of chicken houses and likely have immune-modulating effects. In this study, layers from the 30th generation of a divergent selection experiment for humoral immune reactivity to subcutaneously administered sheep red blood cells were

  1. Uric acid and high-residual platelet reactivity in patients treated with clopidogrel or ticagrelor

    NARCIS (Netherlands)

    Barbieri, L.; Verdoia, M.; Pergolini, P.; Nardin, M.; Rolla, R.; Marino, P.; Bellomo, G.; Suryapranata, H.; Luca, G. De

    2016-01-01

    BACKGROUND AND AIM: High residual platelet reactivity (HRPR) is still an important challenge, despite the advent of new potent ADP-antagonists. Therefore it is of extreme importance to identify factors that can influence platelet activation. Serum uric acid (SUA) has been largely addressed in the

  2. High-sensitivity C-reactive protein predicts target organ damage in Chinese patients with metabolic syndrome

    DEFF Research Database (Denmark)

    Zhao, Zhigang; Nie, Hai; He, Hongbo

    2007-01-01

    with metabolic syndrome. A total of 1082 consecutive patients of Chinese origin were screened for the presence of metabolic syndrome according to the National Cholesterol Education Program's Adult Treatment Panel III. High-sensitivity C-reactive protein and target organ damage, including cardiac hypertrophy...... with the elevated high-sensitivity C-reactive protein had a higher percentage of target organ damage than those with lower high-sensitivity C-reactive protein. Stepwise multiple logistic regression confirmed that high-sensitivity C-reactive protein was significantly associated with cardiac hypertrophy, carotid...

  3. The chemical and mechanical behaviors of polymer / reactive metal systems under high strain rates

    Science.gov (United States)

    Shen, Yubin

    As one category of energetic materials, impact-initiated reactive materials are able to release a high amount of stored chemical energy under high strain rate impact loading, and are used extensively in civil and military applications. In general, polymers are introduced as binder materials to trap the reactive metal powders inside, and also act as an oxidizing agent for the metal ingredient. Since critical attention has been paid on the metal / metal reaction, only a few types of polymer / reactive metal interactions have been studied in the literature. With the higher requirement of materials resistant to different thermal and mechanical environments, the understanding and characterization of polymer / reactive metal interactions are in great demand. In this study, PTFE (Polytetrafluoroethylene) 7A / Ti (Titanium) composites were studied under high strain rates by utilizing the Taylor impact and SHPB tests. Taylor impact tests with different impact velocities, sample dimensions and sample configurations were conducted on the composite, equipped with a high-speed camera for tracking transient images during the sudden process. SHPB and Instron tests were carried out to obtain the stress vs. strain curves of the composite under a wide range of strain rates, the result of which were also utilized for fitting the constitutive relations of the composite based on the modified Johnson-Cook strength model. Thermal analyses by DTA tests under different flow rates accompanied with XRD identification were conducted to study the reaction mechanism between PTFE 7A and Ti when only heat was provided. Numerical simulations on Taylor impact tests and microstructural deformations were also performed to validate the constitutive model built for the composite system, and to investigate the possible reaction mechanism between two components. The results obtained from the high strain rate tests, thermal analyses and numerical simulations were combined to provide a systematic study on

  4. Equilibrium and kinetic mechanism for Reactive Black 5 sorption onto high lime Soma fly ash.

    Science.gov (United States)

    Eren, Zeynep; Acar, Filiz Nuran

    2007-05-08

    Batch adsorption studies were carried out for the sorption of C.I. Reactive Black 5, a reactive dye, onto high lime fly ash, obtained from Soma Thermal Power Plant (Turkey), to be low cost adsorbent. The effect of various experimental parameters such as contact time, adsorbent dose and initial dye concentration were investigated. Determination of the adsorption equilibrium concentrations was determined by UV-vis spectrophotometry analytical method. Equilibrium data were fitted to the Freundlich and Langmuir isotherm equations and the equilibrium data were found to be well represented by the Freundlich isotherm equation. The adsorption kinetics of C.I. Reactive Black 5 onto high lime fly ash were also studied to characterize of the surface complexation reaction. A pseudo-second-order mechanism has been developed to predict the rate constant of the adsorption, the equilibrium capacity and initial adsorption rate with the effect of initial concentration. A single-stage batch adsorber design of the adsorption of C.I. Reactive Black 5 onto high lime fly ash has been studied based on the Freundlich isotherm equation.

  5. Enhanced selection of high affinity DNA-reactive B cells following cyclophosphamide treatment in mice.

    Directory of Open Access Journals (Sweden)

    Daisuke Kawabata

    Full Text Available A major goal for the treatment of patients with systemic lupus erythematosus with cytotoxic therapies is the induction of long-term remission. There is, however, a paucity of information concerning the effects of these therapies on the reconstituting B cell repertoire. Since there is recent evidence suggesting that B cell lymphopenia might attenuate negative selection of autoreactive B cells, we elected to investigate the effects of cyclophosphamide on the selection of the re-emerging B cell repertoire in wild type mice and transgenic mice that express the H chain of an anti-DNA antibody. The reconstituting B cell repertoire in wild type mice contained an increased frequency of DNA-reactive B cells; in heavy chain transgenic mice, the reconstituting repertoire was characterized by an increased frequency of mature, high affinity DNA-reactive B cells and the mice expressed increased levels of serum anti-DNA antibodies. This coincided with a significant increase in serum levels of BAFF. Treatment of transgene-expressing mice with a BAFF blocking agent or with DNase to reduce exposure to autoantigen limited the expansion of high affinity DNA-reactive B cells during B cell reconstitution. These studies suggest that during B cell reconstitution, not only is negative selection of high affinity DNA-reactive B cells impaired by increased BAFF, but also that B cells escaping negative selection are positively selected by autoantigen. There are significant implications for therapy.

  6. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Science.gov (United States)

    Favalli, A.; Vo, D.; Grogan, B.; Jansson, P.; Liljenfeldt, H.; Mozin, V.; Schwalbach, P.; Sjöland, A.; Tobin, S. J.; Trellue, H.; Vaccaro, S.

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)-Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI-SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute 137Cs count rate and the 154Eu/137Cs, 134Cs/137Cs, 106Ru/137Cs, and 144Ce/137Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity's behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  7. Determining initial enrichment, burnup, and cooling time of pressurized-water-reactor spent fuel assemblies by analyzing passive gamma spectra measured at the Clab interim-fuel storage facility in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Favalli, A., E-mail: afavalli@lanl.gov [Los Alamos National Laboratory, Los Alamos, NM (United States); Vo, D. [Los Alamos National Laboratory, Los Alamos, NM (United States); Grogan, B. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Jansson, P. [Uppsala University, Uppsala (Sweden); Liljenfeldt, H. [Oak Ridge National Laboratory, Oak Ridge, TN (United States); Mozin, V. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Schwalbach, P. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg); Sjöland, A. [Swedish Nuclear Fuel and Waste Management Company, Stockholm (Sweden); Tobin, S.J.; Trellue, H. [Los Alamos National Laboratory, Los Alamos, NM (United States); Vaccaro, S. [European Commission, DG Energy, Euratom Safeguards Luxemburg, Luxemburg (Luxembourg)

    2016-06-01

    The purpose of the Next Generation Safeguards Initiative (NGSI)–Spent Fuel (SF) project is to strengthen the technical toolkit of safeguards inspectors and/or other interested parties. The NGSI–SF team is working to achieve the following technical goals more easily and efficiently than in the past using nondestructive assay measurements of spent fuel assemblies: (1) verify the initial enrichment, burnup, and cooling time of facility declaration; (2) detect the diversion or replacement of pins; (3) estimate the plutonium mass [which is also a function of the variables in (1)]; (4) estimate the decay heat; and (5) determine the reactivity of spent fuel assemblies. Since August 2013, a set of measurement campaigns has been conducted at the Central Interim Storage Facility for Spent Nuclear Fuel (Clab), in collaboration with Swedish Nuclear Fuel and Waste Management Company (SKB). One purpose of the measurement campaigns was to acquire passive gamma spectra with high-purity germanium and lanthanum bromide scintillation detectors from Pressurized Water Reactor and Boiling Water Reactor spent fuel assemblies. The absolute {sup 137}Cs count rate and the {sup 154}Eu/{sup 137}Cs, {sup 134}Cs/{sup 137}Cs, {sup 106}Ru/{sup 137}Cs, and {sup 144}Ce/{sup 137}Cs isotopic ratios were extracted; these values were used to construct corresponding model functions (which describe each measured quantity’s behavior over various combinations of burnup, cooling time, and initial enrichment) and then were used to determine those same quantities in each measured spent fuel assembly. The results obtained in comparison with the operator declared values, as well as the methodology developed, are discussed in detail in the paper.

  8. The burnup dependence of light water reactor spent fuel oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, B.D.

    1998-07-01

    Over the temperature range of interest for dry storage or for placement of spent fuel in a permanent repository under the conditions now being considered, UO{sub 2} is thermodynamically unstable with respect to oxidation to higher oxides. The multiple valence states of uranium allow for the accommodation of interstitial oxygen atoms in the fuel matrix. A variety of stoichiometric and nonstoichiometric phases is therefore possible as the fuel oxidizers from UO{sub 2} to higher oxides. The oxidation of UO{sub 2} has been studied extensively for over 40 years. It has been shown that spent fuel and unirradiated UO{sub 2} oxidize via different mechanisms and at different rates. The oxidation of LWR spent fuel from UO{sub 2} to UO{sub 2.4} was studied previously and is reasonably well understood. The study presented here was initiated to determine the mechanism and rate of oxidation from UO{sub 2.4} to higher oxides. During the early stages of this work, a large variability in the oxidation behavior of samples oxidized under nearly identical conditions was found. Based on previous work on the effect of dopants on UO{sub 2} oxidation and this initial variability, it was hypothesized that the substitution of fission product and actinide impurities for uranium atoms in the spent fuel matrix was the cause of the variable oxidation behavior. Since the impurity concentration is roughly proportional to the burnup of a specimen, the oxidation behavior of spent fuel was expected to be a function of both temperature and burnup. This report (1) summarizes the previous oxidation work for both unirradiated UO{sub 2} and spent fuel (Section 2.2) and presents the theoretical basis for the burnup (i.e., impurity concentration) dependence of the rate of oxidation (Sections 2.3, 2.4, and 2.5), (2) describes the experimental approach (Section 3) and results (Section 4) for the current oxidation tests on spent fuel, and (3) establishes a simple model to determine the activation energies

  9. Synthesising highly reactive tin oxide using Tin(II2- ethylhexanoate polynucleation as precursor

    Directory of Open Access Journals (Sweden)

    Alejandra Montenegro Hernández

    2009-01-01

    Full Text Available Tin oxide is a widely used compound in technological applications, particularity as a catalyst, gas sensor and in making varistors, transparent conductors, electrocatalytic electrodes and photovoltaic cells. An ethylhexanoate tin salt, a carboxylic acid and poly-esterification were used for synthesising highly reactive tin oxide in the present study. Synthesis was controlled by Fourier transform infrared (FTIR spectroscopy and recording changes in viscosity. The tin oxide characteristics so obtained were determined using FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The SnO2 dust synthesised and heat-treated at 550°C yielded high density aggregates, having greater than 50 μm particle size. This result demonstrates the high reactivity of the ceramic powders synthesised here.

  10. Synthesising highly reactive tin oxide using Tin(II2- ethylhexanoate polynucleation as precursor

    Directory of Open Access Journals (Sweden)

    Alejandra Montenegro Hernández

    2010-05-01

    Full Text Available Tin oxide is a widely used compound in technological applications, particularity as a catalyst, gas sensor and in making varistors, transparent conductors, electrocatalytic electrodes and photovoltaic cells. An ethylhexanoate tin salt, a carboxylic acid and poly-esterification were used for synthesising highly reactive tin oxide in the present study. Synthesis was controlled by Fourier transform infrared (FTIR spectroscopy and recording changes in viscosity. The tin oxide characteristics so obtained were determined using FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The SnO2 dust synthesised and heat-treated at 550°C yielded high density aggregates, having greater than 50 μm particle size. This result demonstrates the high reactivity of the ceramic powders synthesised here.

  11. Propagation of Nuclear Data Uncertainties for ELECTRA Burn-up Calculations

    Science.gov (United States)

    Sjöstrand, H.; Alhassan, E.; Duan, J.; Gustavsson, C.; Koning, A. J.; Pomp, S.; Rochman, D.; Österlund, M.

    2014-04-01

    The European Lead-Cooled Training Reactor (ELECTRA) has been proposed as a training reactor for fast systems within the Swedish nuclear program. It is a low-power fast reactor cooled by pure liquid lead. In this work, we propagate the uncertainties in 239Pu transport data to uncertainties in the fuel inventory of ELECTRA during the reactor lifetime using the Total Monte Carlo approach (TMC). Within the TENDL project, nuclear models input parameters were randomized within their uncertainties and 740 239Pu nuclear data libraries were generated. These libraries are used as inputs to reactor codes, in our case SERPENT, to perform uncertainty analysis of nuclear reactor inventory during burn-up. The uncertainty in the inventory determines uncertainties in: the long-term radio-toxicity, the decay heat, the evolution of reactivity parameters, gas pressure and volatile fission product content. In this work, a methodology called fast TMC is utilized, which reduces the overall calculation time. The uncertainty of some minor actinides were observed to be rather large and therefore their impact on multiple recycling should be investigated further. It was also found that, criticality benchmarks can be used to reduce inventory uncertainties due to nuclear data. Further studies are needed to include fission yield uncertainties, more isotopes, and a larger set of benchmarks.

  12. Criticality Evaluation of GBC-32 Cask with HBN No.3 Fuels in PWR Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Do-Yeon; Yoon, Hyoungju; Park, Kwangheon; Hong, Ser Gi [Kyung Hee Univ., Yongin (Korea, Republic of)

    2015-10-15

    An application of burnup credit is able to increase the capacity in casks. In this paper, the criticality evaluation for burnup credit was performed for the GBC-32 cask with the fuel assemblies discharged after HBN No.3 Cycle 6 by SCALE6.1/STARBUCS and MCNP6 with the axial burnup distributions and average discharge burnups evaluated using DeCART and MASTER codes. The criticality evaluation for burnup credit was performed for the GBC-32 cask with the fuel assemblies discharged after HBN No.3 Cycle 6 by STARBUCS and MCNP6 codes with the axial burnup distributions and average discharge burnups evaluated using DeCART and MASTER codes. k{sub eff} values and end effects were calculated for 3 cooling times of 0, 20, and 30 years. From the results calculated in these conditions, the following conclusions are drawn. (1) 12 discharged fuel assemblies for the cooling time of 0 year were not allowed to be stored in the cask because the estimated k{sub eff} values exceeds 0.9146. (2) Most of the discharged fuel assemblies except for 3 discharged fuel assemblies were allowed to be stored for the cooling times of 20 and 30 years. (3) The end effects increased as the cooling time increases, within the maximums of 834.93 pcm for the cooling time of 0 year, 1684.45 pcm for 20 years, and 2178.92 pcm for 30 years.

  13. Simulation of triton burn-up in JET plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Loughlin, M.J.; Balet, B.; Jarvis, O.N.; Stubberfield, P.M. [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    This paper presents the first triton burn-up calculations for JET plasmas using the transport code TRANSP. Four hot ion H-mode deuterium plasmas are studied. For these discharges, the 2.5 MeV emission rises rapidly and then collapses abruptly. This phenomenon is not fully understood but in each case the collapse phase is associated with a large impurity influx known as the ``carbon bloom``. The peak 14 MeV emission occurs at this time, somewhat later than that of the 2.5 MeV neutron peak. The present results give a clear indication that there are no significant departures from classical slowing down and spatial diffusion for tritons in JET plasmas. (authors). 7 refs., 3 figs., 1 tab.

  14. Triton burnup study using scintillating fiber detector on JT-60U

    Energy Technology Data Exchange (ETDEWEB)

    Harano, Hideki [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment

    1997-09-01

    The DT fusion reactor cannot be realized without knowing how the fusion-produced 3.5 MeV {alpha} particles behave. The {alpha} particles` behavior can be simulated using the 1 MeV triton. To investigate the 1 MeV triton`s behavior, a new type of directional 14 MeV neutron detector, scintillating fiber (Sci-Fi) detector has been developed and installed on JT-60U in the cooperation with LANL as part of a US-Japan collaboration. The most remarkable feature of the Sci-Fi detector is that the plastic scintillating fibers are employed for the neutron sensor head. The Sci-Fi detector measures and extracts the DT neutrons from the fusion radiation field in high time resolution (10 ms) and wide dynamic range (3 decades). Triton burnup analysis code TBURN has been made in order to analyze the time evolution of DT neutron emission rate obtained by the Sci-Fi detector. The TBURN calculations reproduced the measurements fairly well, and the validity of the calculation model that the slowing down of the 1 MeV triton was classical was confirmed. The Sci-Fi detector`s directionality indicated the tendency that the DT neutron emission profile became more and more peaked with the time progress. In this study, in order to examine the effect of the toroidal field ripple on the triton burnup, R{sub p}-scan and n{sub e}-scan experiments have been performed. The R{sub p}-scan experiment indicates that the triton`s transport was increased as the ripple amplitude over the triton became larger. In the n{sub e}-scan experiment, the DT neutron emission showed the characteristic changes after the gas puffing injection. It was theoretically confirmed that the gas puffing was effective for the collisionality scan. (J.P.N.) 127 refs.

  15. SERUM LEVELS OF HIGH SENSITIVITY C REACTIVE PROTEIN AND MALONDIALDEHYDE IN CHRONIC KIDNEY DISEASE

    Directory of Open Access Journals (Sweden)

    Rakshitha Gowda B.H, Meera K.S , Mahesh E

    2015-07-01

    Full Text Available Background: Chronic kidney disease cases are at increased risk for progression to end stage renal disease and accelerated atherosclerosis, with premature cardiovascular morbidity and mortality being the more frequent outcome. Aim: The study was taken up to find if there is any association between nontraditional cardiovascular risk markers like high sensitivity C reactive protein (marker of inflammation and malondialdehyde (marker of lipid peroxidation with the progression of chronic kidney disease. Methodology: The study included 44 pre dialysis chronic kidney disease cases and 44 healthy controls. Serum levels of creatinine, high sensitivity C reactive protein and malondialdehyde were estimated in both groups. The mean estimated glomerular filtration rate(eGFR in chronic kidney disease patients was calculated by the MDRD formula. Results: The mean eGFR in cases was found to be 23.65 14.99 ml/min by MDRD formula. The serum hsCRP and malondialdehyde levels in cases was 11.8 7.24 mg/L and 3.02 1.24 nmol/ml respectively. Conclusion: There was a significant negative correlation (p<0.001 between high sensitivity C-reactive protein and malondialdehyde with eGFR. A highly significant positive correlation was found between serum hsCRP and malondialdehyde (p<0.001 in chronic kidney disease underlining the synergism between oxidative stress and inflammation, perpetuating to further deterioration of renal function and enhancing the predisposition to cardiovascular risk with the progression of chronic kidney disease.

  16. Burnup measurements on spent fuel elements of the RP-10 research reactor

    Energy Technology Data Exchange (ETDEWEB)

    Vela Mora, Mariano; Gallardo Padilla, Alberto; Palomino, Jose Luis Castro, E-mail: mvela@ipen.gob.p [Instituto Peruano de Energia Nuclear (IPEN/Peru), Lima (Peru). Grupo de Calculo, Analisis y Seguridad de Reactores; Terremoto, Luis Antonio Albiac, E-mail: laaterre@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-07-01

    This work describes the measurement, using nondestructive gamma-ray spectroscopy, of the average burnup attained by Material Testing Reactor (MTR) fuel elements irradiated in the RP-10 research reactor. Measurements were performed at the reactor storage pool area using {sup 137}Cs as the only burnup monitor, even for spent fuel elements with cooling times much shorter than two years. The experimental apparatus was previously calibrated in efficiency to obtain absolute average burnup values, which were compared against corresponding ones furnished by reactor physics calculations. The mean deviation between both values amounts to 6%. (author)

  17. Successful treatment of reactive airways dysfunction syndrome by high-dose vitamin D

    Directory of Open Access Journals (Sweden)

    Varney VA

    2011-09-01

    Full Text Available Veronica A Varney1, Jane Evans1, Amolak S Bansal2 1Department of Respiratory Medicine, 2Department of Immunology and Allergy, St. Helier Hospital, Carshalton, Surrey, UK Abstract: Reactive airways dysfunction syndrome is a controversial and poorly understood condition produced by inhalational injury from gas, vapors, or fumes. The symptoms mimic asthma, but appear unresponsive to asthma treatments. If symptoms persist for more than 6 months, there is a risk that they can become chronic. For these cases, effective treatments are lacking and quality of life is poor. We describe the first use of high-dose vitamin D in a patient with this condition, who fulfilled the 1995 American College of Chest Physicians criteria for this syndrome. The patient we describe presented an extremely difficult management problem and was refractory to conventional treatments, but responded to high-dose oral vitamin D supplements. Keywords: asthma, vitamin D, reactive airways dysfunction syndrome, cough, inhalational injury

  18. Actinide-only and full burn-up credit in criticality assessment of RBMK-1500 spent nuclear fuel storage cask using axial burn-up profile

    Energy Technology Data Exchange (ETDEWEB)

    Barkauskas, V., E-mail: vytenis.barkauskas@ftmc.lt; Plukiene, R., E-mail: rita.plukiene@ftmc.lt; Plukis, A., E-mail: arturas.plukis@ftmc.lt

    2016-10-15

    Highlights: • RBMK-1500 fuel burn-up impact on k{sub eff} in the SNF cask was calculated using SCALE 6.1. • Positive end effect was noticed at certain burn-up for the RBMK-1500 spent nuclear fuel. • The non-uniform uranium depletion is responsible for the end effect in RBMK-1500 SNF. • k{sub eff} in the SNF cask does not exceed a value of 0.95 which is set in the safety requirements. - Abstract: Safe long-term storage of spent nuclear fuel (SNF) is one of the main issues in the field of nuclear safety. Burn-up credit application in criticality analysis of SNF reduces conservatism of usually used fresh fuel assumption and implies a positive economic impact for the SNF storage. Criticality calculations of spent nuclear fuel in the CONSTOR® RBMK-1500/M2 cask were performed using pre-generated ORIGEN-ARP spent nuclear fuel composition libraries, and the results of the RBMK-1500 burn-up credit impact on the effective neutron multiplication factor (k{sub eff}) have been obtained and are presented in the paper. SCALE 6.1 code package with the STARBUCKS burn-up credit evaluation tool was used for modeling. Pre-generated ARP (Automatic Rapid Processing) crosssection libraries based on ENDF/B-VII cross section library were used for fast burn-up inventory modeling. Different conditions in the SNF cask were modeled: 2.0% and 2.8% initial enrichment fuel of various burn-up and water density inside cavities of the SNF cask. The fuel composition for the criticality analysis was chosen taking into account main actinides and most important fission products used in burn-up calculations. A significant positive end effect is noticed from 15 GWd/tU burn-up for 2.8% enrichment fuel and from 9 GWd/tU for 2.0% enrichment fuel applying the actinide-only approach. The obtained results may be applied in further evaluations of the RBMK type reactor SNF storage as well as help to optimize the SNF storage volume inside the CONSTOR® RBMK-1500/M2 cask without compromising criticality

  19. Reactive sputtering methods used for the preparation of high critical temperature superconducting thin films

    Energy Technology Data Exchange (ETDEWEB)

    Bruyere, J.C.; Escribe-Filippini, C.; Marcus, J.; Reydet, P.L.; Cabaret, B.

    1988-06-01

    Among the synthesis methods of metallic oxides, the reactive sputtering methods seem to be the most attractive, with the possibilities to get the right composition and even the suitable crystalline structure. In this paper, we discuss many specific chemical and physical reactions which appear during the deposition process. Finally, we show preliminary results obtained in our laboratory in the preparation of high critical temperature superconducting thin films.

  20. Reactive Processing and Co-Extrusion of Ultra-High Temperature Ceramics and Composites

    Science.gov (United States)

    2006-02-28

    Faenza, Italy. Ultra-high temperature ceramics (UHTCs) are a unique class of materials with melting temperatures in excess of 3000’C. The borides ...composites with silicon carbide (SiC) and molybdenum disilicide (MoSi 2) were examined. Two main approaches were pursued: 1) the use of reactive processing...Diboride- Molybdenum Disilicide Ceramics," pp. 299-308 in Advances in Ceramic Matrix Composites IX, Ceramic Transactions, Volume 153, ed. by N.P. Bansal, J.P

  1. Highly Human Immunodeficiency Virus-Exposed Seronegative Men Have Lower Mucosal Innate Immune Reactivity.

    Science.gov (United States)

    Fulcher, Jennifer A; Romas, Laura; Hoffman, Jennifer C; Elliott, Julie; Saunders, Terry; Burgener, Adam D; Anton, Peter A; Yang, Otto O

    2017-08-01

    Risk of HIV acquisition varies, and some individuals are highly HIV-1-exposed, yet, persistently seronegative (HESN). The immunologic mechanisms contributing to this phenomenon are an area of intense interest. As immune activation and inflammation facilitate disease progression in HIV-1-infected persons and gastrointestinal-associated lymphoid tissue is a highly susceptible site for transmission, we hypothesized that reduced gut mucosal immune reactivity may contribute to reduced HIV-1 susceptibility in HESN men with a history of numerous rectal sexual exposures. To test this, we used ex vivo mucosal explants from freshly acquired colorectal biopsies from healthy control and HESN subjects who were stimulated with specific innate immune ligands and inactivated whole pathogens. Immune reactivity was then assessed via cytokine arrays and proteomic analysis. Mucosal immune cell compositions were quantified via immunohistochemistry. We found that explants from HESN subjects produced less proinflammatory cytokines compared with controls following innate immune stimulation; while noninflammatory cytokines were similar between groups. Proteomic analysis identified several immune response proteins to be differentially expressed between HIV-1-stimulated HESN and control explants. Immunohistochemical examination of colorectal mucosa showed similar amounts of T cells, macrophages, and dendritic cells between groups. The results of this pilot study suggest that mucosal innate immune reactivity is dampened in HESN versus control groups, despite presence of similar densities of immune cells in the colorectal mucosa. This observed modulation of the rectal mucosal immune response may contribute to lower risk of mucosal HIV-1 transmission in these individuals.

  2. Magnesium hydroxide coagulation performance and floc properties in treating high pH reactive orange wastewater.

    Science.gov (United States)

    Liu, Meile; Lu, Jingfang; Wei, Lei; Wang, Kang; Zhao, Jianhai

    2015-01-01

    Application of magnesium hydroxide as a coagulant for treating high pH reactive orange wastewater was studied. The coagulation performance and magnesium hydroxide-reactive orange floc properties were investigated under different dosages, feeding modes and pH values. Flocculation index (FI) was then discussed with controlled experiments using an intelligent particle dispersion analyzer and optimum coagulant dose of 150 mg/L (magnesium ion) was obtained for pH value 12. The results showed that the optimum magnesium ion dose tended to decrease with the increase of initial pH value. One time addition feeding mode led to relatively large FI value and higher removal efficiency compared with other addition modes. All of the flocs under investigation showed a limited capacity for re-growth when they had been previously broken. Based on the changes of zeta potential and floc properties, charge neutralization and precipitate enmeshment were proposed to be the main coagulation mechanisms.

  3. High-sensitive C-reactive protein is associated with reduced lung function in young adults

    DEFF Research Database (Denmark)

    Rasmussen, Finn; Mikkelsen, Dennis; Hancox, Robert

    2009-01-01

    Systemic inflammation has been associated with reduced lung function. However, data on the interrelationships between lung function and inflammation are sparse, and it is not clear if low-grade inflammation leads to reduced lung function. Associations between high-sensitive C-reactive protein (CRP...... decline was 6.2 mL.yr(-1) in the highest CRP quintile versus an increase of 1.8 mL.yr(-1) in the lowest CRP quintile. In a multiple regression analysis adjusted for sex, body mass index, cardiorespiratory fitness, smoking, asthma, airway hyperresponsiveness and serum eosinophil cationic protein, higher...... levels of CRP at age 20 yrs were associated with a greater reduction in both FEV(1) and forced vital capacity between ages 20 and 29 yrs. The findings show that higher levels of C-reactive protein in young adults are associated with subsequent decline in lung function, suggesting that low-grade systemic...

  4. Development of Technical Basis for Burnup Credit Regulatory Guidance in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Parks, Cecil V [ORNL; Wagner, John C [ORNL; Mueller, Don [ORNL; Gauld, Ian C [ORNL

    2011-01-01

    In the United States (U.S.) there has been and continues to be considerable interest in the increased use of burnup credit as part of the safety basis for SNF systems and this interest has motivated numerous technical studies related to the application of burnup credit for maintaining subcriticality. Responding to industry requests and needs, the U.S. Nuclear Regulatory Commission initiated a burnup credit research program, with support from the Oak Ridge National Laboratory, to develop regulatory guidance and the supporting technical basis for allowing and expanding the use of burnup credit in pressurized-water reactor SNF storage and transport applications. The objective of this paper is to summarize the work and significant accomplishments, with references to the technical reports and publications for complete details.

  5. Technical Development on Burn-up Credit for Spent LWR Fuel

    Energy Technology Data Exchange (ETDEWEB)

    Gauld, I.C.

    2001-12-26

    Technical development on burn-up credit for spent LWR fuels had been performed at JAERI since 1990 under the contract with Science and Technology Agency of Japan entitled ''Technical Development on Criticality Safety Management for Spent LWR Fuels.'' Main purposes of this work are to obtain the experimental data on criticality properties and isotopic compositions of spent LWR fuels and to verify burnup and criticality calculation codes. In this work three major experiments of exponential experiments for spent fuel assemblies to obtain criticality data, non-destructive gamma-ray measurement of spent fuel rods for evaluating axial burn-up profiles, and destructive analyses of spent fuel samples for determining precise burn-up and isotopic compositions were carried out. The measured data obtained were used for validating calculation codes as well as an examination of criticality safety analyses. Details of the work are described in this report.

  6. On the condition of UO2 nuclear fuel irradiated in a PWR to a burn-up in excess of 110 MWd/kgHM

    Science.gov (United States)

    Restani, R.; Horvath, M.; Goll, W.; Bertsch, J.; Gavillet, D.; Hermann, A.; Martin, M.; Walker, C. T.

    2016-12-01

    Post-irradiation examination results are presented for UO2 fuel from a PWR fuel rod that had been irradiated to an average burn-up of 105 MWd/kgHM and showed high fission gas release of 42%. The radial distribution of xenon and the partitioning of fission gas between bubbles and the fuel matrix was investigated using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and electron probe microanalysis. It is concluded that release from the fuel at intermediate radial positions was mainly responsible for the high fission gas release. In this region thermal release had occurred from the high burn-up structure (HBS) at some point after the sixth irradiation cycle. The LA-ICP-MS results indicate that gas release had also occurred from the HBS in the vicinity of the pellet periphery. It is shown that the gas pressure in the HBS pores is well below the pressure that the fuel can sustain.

  7. The Kinetic Determinants of Reactive Strength in Highly Trained Sprint Athletes.

    Science.gov (United States)

    Douglas, Jamie; Pearson, Simon; Ross, Angus; McGuigan, Mike

    2017-09-11

    The purpose of this study was to determine the braking and propulsive phase kinetic variables underpinning reactive strength in highly trained sprint athletes in comparison to a non-sprint trained control group. Twelve highly trained sprint athletes and twelve non-sprint trained participants performed drop jumps (DJs) from 0.25m, 0.50m and 0.75m onto a force plate. One familiarization session was followed by an experimental testing session within the same week. Reactive strength index (RSI), contact time, flight time, and leg stiffness were determined. Kinetic variables including force, power and impulse were assessed within the braking and propulsive phases. Sprint trained athletes demonstrated higher RSI versus non-sprint trained participants across all drop heights (3.02 vs 2.02; ES [±90% CL]: 3.11 ±0.86). This difference was primarily attained by briefer contact times (0.16 vs 0.22 s; ES: -1.49 ±0.53) with smaller differences observed for flight time (0.50 vs 0.46 s; ES: 0.53 ±0.58). Leg stiffness, braking and propulsive phase force and power were higher in sprint trained athletes. Very large differences were observed in mean braking force (51 vs 38 Nkg; ES: 2.57 ±0.73) which was closely associated with contact time (r ±90% CL: -0.93 ±0.05). Sprint trained athletes exhibited superior reactive strength than non-sprint trained participants. This was due to the ability to strike the ground with a stiffer leg spring, an enhanced expression of braking force, and possibly an increased utilization of elastic structures. The DJ kinetic analysis provides additional insight into the determinants of reactive strength which may inform subsequent testing and training.

  8. Topical Report on Actinide-Only Burnup Credit for PWR Spent Nuclear Fuel Packages. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1998-09-01

    The objective of this topical report is to present to the NRC for review and acceptance a methodology for using burnup credit in the design of criticality control systems for PWR spent fuel transportation packages, while maintaining the criticality safety margins and related requirements of 10 CFR Part 71 and 72. The proposed methodology consists of five major steps as summarized below: (1) Validate a computer code system to calculate isotopic concentrations in SNF created during burnup in the reactor core and subsequent decay. (2) Validate a computer code system to predict the subcritical multiplication factor, keff, of a spent nuclear fuel package. (3) Establish bounding conditions for the isotopic concentration and criticality calculations. (4) Use the validated codes and bounding conditions to generate package loading criteria (burnup credit loading curves). and (5) Verify that SNF assemblies meet the package loading criteria and confirm proper fuel assembly selection prior to loading. (This step is required but the details are outside the scope of this topical report.) When reviewed and accepted by the NRC, this topical report will serve as a criterion document for criticality control analysts and will provide steps for the use of actinide-only burnup credit in the design of criticality control systems. The NRC-accepted burnup credit methodology will be used by commercial SNF storage and transportation package designers. Design-specific burnup credit criticality analyses will be defined, developed, and documented in the Safety Analysis Report (SAR) for each specific storage or transportation package that uses burnup credit. These SARs will then be submitted to the NRC for review and approval. This topical report is expected to be referenced in a number of storage and transportation cask applications to be submitted by commercial cask and canister designers to the NRC. Therefore, NRC acceptance of this topical report will result in increased efficiency of the

  9. Sustainability of thorium-uranium in pebble-bed fluoride salt-cooled high temperature reactor

    Directory of Open Access Journals (Sweden)

    Zhu Guifeng

    2016-01-01

    Full Text Available Sustainability of thorium fuel in a Pebble-Bed Fluoride salt-cooled High temperature Reactor (PB-FHR is investigated to find the feasible region of high discharge burnup and negative Flibe (2LiF-BeF2 salt Temperature Reactivity Coefficient (TRC. Dispersion fuel or pellet fuel with SiC cladding and SiC matrix is used to replace the tristructural-isotropic (TRISO coated particle system for increasing fuel loading and decreasing excessive moderation. To analyze the neutronic characteristics, an equilibrium calculation method of thorium fuel self-sustainability is developed. We have compared two refueling schemes (mixing flow pattern and directional flow pattern and two kinds of reflector materials (SiC and graphite. This method found that the feasible region of breeding and negative Flibe TRC is between 20 vol% and 62 vol% fuel loading in the fuel. A discharge burnup could be achieved up to about 200 MWd/kgHM. The case with directional flow pattern and SiC reflector showed superior burnup characteristics but the worst radial power peak factor, while the case with mixing flow pattern and SiC reflector, which was the best tradeoff between discharge burnup and radial power peak factor, could provide burnup of 140 MWd/kgHM and about 1.4 radial power peak factor with 50 vol% dispersion fuel. In addition, Flibe salt displays good neutron properties as a coolant of quasi-fast reactors due to the strong 9Be(n,2n reaction and low neutron absorption of 6Li (even at 1000 ppm in fast spectrum. Preliminary thermal hydraulic calculation shows good safety margin. The greatest challenge of this reactor may be the decades irradiation time of the pebble fuel.

  10. Nanometer scale high-aspect-ratio trench etching at controllable angles using ballistic reactive ion etching

    Energy Technology Data Exchange (ETDEWEB)

    Cybart, Shane; Roediger, Peter; Ulin-Avila, Erick; Wu, Stephen; Wong, Travis; Dynes, Robert

    2012-11-30

    We demonstrate a low pressure reactive ion etching process capable of patterning nanometer scale angled sidewalls and three dimensional structures in photoresist. At low pressure the plasma has a large dark space region where the etchant ions have very large highly-directional mean free paths. Mounting the sample entirely within this dark space allows for etching at angles relative to the cathode with minimal undercutting, resulting in high-aspect ratio nanometer scale angled features. By reversing the initial angle and performing a second etch we create three-dimensional mask profiles.

  11. Reactivity effects of fission product decay in PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Aragones, J.M.; Ahnert, C.

    1988-01-01

    The purpose of the work reported in this paper is to analyze the effects of fission product chains with radioactive decay on the reactivity in pressurized water reactor (PWR) cores, calculating their accumulation and absorption rates along fuel burnup at continuous operation and after shutdown periods extending from 1 day to a few months. The authors PWR version of the WIMS-D4 code is first used to obtain the individual number densities, absorption rates, and averaged cross sections for every nuclide of the fission product chains with significant decay rates, as a function of fuel burnup at continuous irradiation. Next, by an auxiliary ad hoc code, these data, have been processed together with the required one for fissile nuclides and boron, also taken from WIMS at each burnup step, to calculate the average or effective values relevant for the analysis and the decay and change in overall absorption after several shutdown times. (1) The reactivity effect of fission product decay changes significantly with the shutdown time. The maximum absorption increase by decay is reached in /approx/ 10 days' shutdown. (2) The dependence with fuel type, enrichment, and burnup is slight, but the change with previous power density is nearly linear, which might be significant after coast-down in previous cycles. (3) For long shutdown periods, the overall reactivity effect of decay in the three fission product chains considered is much less than if only the samarium peak due to /sup 149/Nd is considered.

  12. Ticagrelor versus high dose clopidogrel in ST-segment elevation myocardial infarction patients with high platelet reactivity post fibrinolysis.

    Science.gov (United States)

    Alexopoulos, Dimitrios; Perperis, Angelos; Koniari, Ioanna; Karvounis, Haralambos; Patsilinakos, Sotirios; Ziakas, Antonios; Barampoutis, Nikolaos; Panagiotidis, Theofilos; Akinosoglou, Karolina; Hahalis, George; Xanthopoulou, Ioanna

    2015-10-01

    Limited data are available on high platelet reactivity (HPR) rate early post fibrinolysis, while no effective way to overcome it has been proposed. In this context, we aimed to compare ticagrelor versus high dose clopidogrel in patients with ST-segment elevation myocardial infarction (STEMI) who exhibit HPR post fibrinolysis. In a prospective, randomized, parallel design, 3-center study, 56 STEMI patients, out of 83 (67.5 %) screened, who presented with HPR (PRU ≥ 208 by VerifyNow) 3-48 h post fibrinolysis and prior to coronary angiography were allocated to ticagrelor 180 mg loading dose (LD)/90 mg bid maintenance dose (MD) or clopidogrel 600 mg LD/150 mg MD. Platelet reactivity was assessed at randomization (Hour 0), at Hour 2, Hour 24 and pre-discharge. The primary endpoint of platelet reactivity (in PRU) at Hour 2 was significantly lower for ticagrelor compared to clopidogrel with a least square mean difference (95 % confidence interval) of -141.7 (-173.4 to -109.9), p fibrinolysis HPR is common. Ticagrelor treats HPR more effectively compared to high dose clopidogrel therapy. Although antiplatelet regimens tested in this study were well tolerated, this finding should be considered only exploratory.

  13. Abundance of DNA adducts of 4-oxo-2-alkenals, lipid peroxidation-derived highly reactive genotoxins.

    Science.gov (United States)

    Kawai, Yoshichika; Nuka, Erika

    2018-01-01

    Reactive oxygen species and their reaction products can damage DNA to form mutagenic lesions. Among the reactive species, lipid peroxidation-derived aldehydes react with nucleobases and form bulky exocyclic adducts. Many types of aldehyde-derived DNA adducts have been characterized, identified and detected in vitro and in vivo , whereas relative quantitative and pathophysiological contributions of each adduct still remain unclear. In recent years, an abundant class of DNA adducts derived from 4-oxo-2-alkenals have been identified, in addition to classic aldehyde-derived adducts. The presence of 4-oxo-2-alkenal-derived DNA adducts associated with age-related diseases has been revealed in rodents and humans. In vitro studies have demonstrated that 4-oxo-2-alkenals, as compared with other classes of lipid peroxidation-derived aldehydes, are highly reactive with nucleobases. It has been generally recognized that 4-oxo-2-alkenals are generated through oxidative degradation of the corresponding 4-hydroperoxy-2-alkenals, homolytic degradation products of polyunsaturated fatty acid hydroperoxides. Our recent results have also shown an alternative pathway for the formation of 4-oxo-2-alkenals, in which 2-alkenals could undergo the metal-catalyzed autoxidation resulting in the formation of the corresponding 4-oxo-2-alkenals. This review summarizes the basis of the formation of lipid peroxidation-derived genotoxic aldehydes and their covalent adduction to nucleobases, especially focusing on the abundance of 4-oxo-2-alkenal-derived DNA adducts.

  14. THC-MP: High performance numerical simulation of reactive transport and multiphase flow in porous media

    Science.gov (United States)

    Wei, Xiaohui; Li, Weishan; Tian, Hailong; Li, Hongliang; Xu, Haixiao; Xu, Tianfu

    2015-07-01

    The numerical simulation of multiphase flow and reactive transport in the porous media on complex subsurface problem is a computationally intensive application. To meet the increasingly computational requirements, this paper presents a parallel computing method and architecture. Derived from TOUGHREACT that is a well-established code for simulating subsurface multi-phase flow and reactive transport problems, we developed a high performance computing THC-MP based on massive parallel computer, which extends greatly on the computational capability for the original code. The domain decomposition method was applied to the coupled numerical computing procedure in the THC-MP. We designed the distributed data structure, implemented the data initialization and exchange between the computing nodes and the core solving module using the hybrid parallel iterative and direct solver. Numerical accuracy of the THC-MP was verified through a CO2 injection-induced reactive transport problem by comparing the results obtained from the parallel computing and sequential computing (original code). Execution efficiency and code scalability were examined through field scale carbon sequestration applications on the multicore cluster. The results demonstrate successfully the enhanced performance using the THC-MP on parallel computing facilities.

  15. High fluence laser irradiation induces reactive oxygen species generation in human lung adenocarcinoma cells

    Science.gov (United States)

    Wang, Fang; Xing, Da; Chen, Tong-Sheng

    2006-09-01

    Low-power laser irradiation (LPLI) has been used for therapies such as curing spinal cord injury, healing wound et al. Yet, the mechanism of LPLI remains unclear. Our previous study showed that low fluences laser irradiation induces human lung adenocarcinoma cells (ASTC-a-1) proliferation, but high fluences induced apoptosis and caspase-3 activation. In order to study the mechanism of apoptosis induced by high fluences LPLI further, we have measured the dynamics of generation of reactive oxygen species (ROS) using H IIDCFDA fluorescence probes during this process. ASTC-a-1 cells apoptosis was induced by He-Ne laser irradiation at high fluence of 120J/cm2. A confocal laser scanning microscope was used to perform fluorescence imaging. The results demonstrated that high fluence LPLI induced the increase of mitochondria ROS. Our studies contribute to clarify the biological mechanism of high fluence LPLI-induced cell apoptosis.

  16. On the issue of Zircaloy ductility during a reactivity-initiated accident

    Energy Technology Data Exchange (ETDEWEB)

    Link, T.M.; Motta, A.T.; Koss, D.A. [Pennsylvania State Univ., University Park, PA (United States)

    1997-01-01

    During reactor exposure, Zircaloy cladding undergoes various microstructural changes including irradiation damage, oxidation, and hydrogen pick-up. There is a concern that the combination of these changes in high burnup cladding will cause failure during a reactivity-initiated accident (RIA) at an energy deposition level significantly lower than that of fresh cladding. In RIA conditions, the cladding must withstand loading at high strain rates and under deformation paths close to transverse plane-strain extension. Thus to assess cladding failure it is necessary to examine the failure mechanism of unirradiated Zircaloy cladding under RIA-like loading conditions. The authors present here a theoretical analysis of a possible failure mode of Zircaloy cladding due to localized necking. The results of the analysis suggest that high-burnup cladding is susceptible to pronounced losses of ductility under a combination of plane strain loading deformation and the presence of thickness imperfections. Such imperfections may be caused by hydride embrittlement of the cladding or non-uniform oxidation such that an axial thickness change is created.

  17. Application of an enhanced cross-section interpolation model for highly poisoned LWR core calculations

    Energy Technology Data Exchange (ETDEWEB)

    Palau, J.M.; Cathalau, S.; Hudelot, J.P.; Barran, F.; Bellanger, V., E-mail: jean-marc.palau@cea.fr [CEA, DEN, Departement d' Etudes des Reacteurs, Service de Physique des Reacteurs et du Cycle Laboratoire de Projets Nucleaires, Cadarache, Saint-Paul-lez-Durance (France); Magnaud, C.; Moreau, F., E-mail: Christine.magnaud@cea.fr [Departement de Modelisation des Systemes et des Structures Service d' Etudes de Reacteurs et Mathematiques Appliquees, Saclay (France)

    2011-07-01

    Burnable poisons are extensively used by Light Water Reactor designers in order to preserve the fuel reactivity potential and increase the cycle length (without increasing the uranium enrichment). In the industrial two-steps (assembly 2D transport-core 3D diffusion) calculation schemes these heterogeneities yield to strong flux and cross-sections perturbations that have to be taken into account in the final 3D burn-up calculations. This paper presents the application of an enhanced cross-section interpolation model (implemented in the French CRONOS2 code) to LWR (highly poisoned) depleted core calculations. The principle is to use the absorbers (or actinide) concentrations as the new interpolation parameters instead of the standard local burnup/fluence parameters. It is shown by comparing the standard (burnup/fluence) and new (concentration) interpolation models and using the lattice transport code APOLLO2 as a numerical reference that reactivity and local reaction rate prediction of a 2x2 LWR assembly configuration (slab geometry) is significantly improved with the concentration interpolation model. Gains on reactivity and local power predictions (resp. more than 1000 pcm and 20 % discrepancy reduction compared to the reference APOLLO2 scheme) are obtained by using this model. In particular, when epithermal absorbers are inserted close to thermal poison the 'shadowing' ('screening') spectral effects occurring during control operations are much more correctly modeled by concentration parameters. Through this outstanding example it is highlighted that attention has to be paid to the choice of cross-section interpolation parameters (burnup 'indicator') in core calculations with few energy groups and variable geometries all along the irradiation cycle. Actually, this new model could be advantageously applied to steady-state and transient LWR heterogeneous core computational analysis dealing with strong spectral-history variations under

  18. High intensity exercise enhances platelet reactivity to shear stress and coagulation during and after exercise.

    Science.gov (United States)

    Ikarugi, Hideo; Shibata, Masashi; Shibata, Shiori; Ishii, Hiromitsu; Taka, Tomomi; Yamamoto, Junichiro

    2003-01-01

    Platelets play a crucial role in the pathogenesis of acute cardiac events, such as angina, myocardial infarction and sudden death. It is believed that regular low-intensity exercise can reduce, while high-intensity exercise may provoke acute cardiac events. The aim of the present study was to investigate the effect of acute exercise both at low and high intensities on the ventilatory threshold (VT), platelet reactivity and coagulation before and after exercise. Platelet reactivity and coagulation were measured under flow condition, using native blood, by hemostatometry. Seven healthy young men (age: 20-29 years) performed bicycle ergometer exercise for 30 min at intensities of 90% (Ex-VT90% or approximately 55% VO(2max)) and 130% (Ex-VT130% or 80% VO(2max)) of individual VT. Blood cell counts, hematocrit, blood lactic acid and plasma catecholamine levels were slightly but significantly increased after Ex-VT90% and markedly after Ex-VT130% after 30 min exercise. Subsequent to the exercise, the elevated blood cell counts decreased to the resting levels both at Ex-VT90% and at Ex-VT130%. Platelet reactivity to shear stress and dynamic coagulation were significantly enhanced immediately and 30 min after Ex-130%VT. In contrast, no significant changes occurred in those of Ex-90%VT. The present study suggests that high-intensity exercise-induced platelet hyperreactivity and hypercoagulable state may pose an increased risk for acute, sometimes fatal cardiac event. On the other hand, our findings support the view that low-intensity exercise does not present a risk of thrombosis. Copyright 2003 S. Karger AG, Basel

  19. Investigation of accessibility and reactivity of cellulose pretreated by ionic liquid at high loading.

    Science.gov (United States)

    Endo, Takatsugu; Aung, Ei Mon; Fujii, Shunsuke; Hosomi, Shota; Kimizu, Mitsugu; Ninomiya, Kazuaki; Takahashi, Kenji

    2017-11-15

    High loading of cellulose in ionic liquid (IL) pretreatment is potentially a key technique for cellulose conversion to glucose in biorefining. In this work, to expand the potential use of this high loading technique, the accessibility of microcrystalline cellulose pretreated with an IL across a wide cellulose loading range (5-50mol%) and its relationship with the hydrolytic reactivity were comprehensively investigated. The results show that the estimated cellulose accessibility based on the crystallinity and specific surface area was notably higher in 25mol% loading than that for a conventional loading of 5mol%. Consistently, acid-catalyzed glucose conversion was faster at this high loading, showing that a higher cellulose loading improves the pretreatment efficiency. In contrast, enzymatic hydrolysis was not enhanced by a high cellulose loading. A key difference between the activities in these two hydrolytic reactions is the catalyst size. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Water-free synthesis of polyurethane foams using highly reactive diisocyanates derived from 5-hydroxymethylfurfural.

    Science.gov (United States)

    Neumann, Christopher N D; Bulach, Winfried D; Rehahn, Matthias; Klein, Roland

    2011-09-01

    This paper reports on the synthesis of a new highly reactive diisocyanate monomer based on hydroxymethylfurfural. It further describes its catalyst-free conversion to linear-chain thermoplastic polyurethanes as well as to cross-linked polyurethane foams. In addition, a novel strategy for the synthesis of polyurethane foams without the necessity of using water is developed. Nitrogen is utilized herein as blowing agent which is formed during Curtius rearrangement of a new furan based carboxylic azide into its corresponding diisocyanate. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. High Density MgB2 Obtained by Reactive Liquid Mg Infiltration

    OpenAIRE

    Giunchi, Giovanni

    2002-01-01

    A new route to the sintering of MgB2 has been identified, based on a reactive infiltration of liquid Mg on a powdered B preform. The technique allows to obtain large bulk manufacts in an inexpensive way, without the need of high pressure apparatus. The best of the obtained samples shows a transport current density of 3 kA/cm2 at 4.2K and 9 T. The critical aspects of the technology are presented, together with the recent achievements and the perspective applications.

  2. Fluidizable zinc titanate materials with high chemical reactivity and attrition resistance

    Science.gov (United States)

    Gupta, Raghubir P.; Gangwal, Santosh K.; Jain, Suresh C.

    1993-01-01

    Highly durable and chemically reactive zinc titanate materials are prepared in a particle size range of 50 to 400 .mu.m suitable for a fluidized-bed reactor for removing reduced sulfur species in a gaseous form by granulating a mixture of fine zinc oxide and titanium oxide with inorganic and organic binders and by optional additions of small amounts of activators such as CoO and MoO.sub.3 ; and then indurating it at 800.degree. to 900.degree. C. for a time sufficient to produce attrition-resistant granules.

  3. Reactive Fusion Welding for Ultra-High Temperature Ceramic Composite Joining

    Science.gov (United States)

    2015-03-16

    welding was used to join diboride based ceramics . Billets of diborides such as ZrB2, TiB2, and HfB2 were fabricated and machined into smaller...3000 ○ C. The general public thinks of 63 ceramics as sinks, tiles , or plates. Further, ask the average non-materials engineer to describe a...FA9550-12-C-0060 Reactive Fusion W elding for Ultra-High Temperatu re Ceramic Composite Joining 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  4. Topical report on actinide-only burnup credit for PWR spent nuclear fuel packages. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    1997-04-01

    A methodology for performing and applying nuclear criticality safety calculations, for PWR spent nuclear fuel (SNF) packages with actinide-only burnup credit, is described. The changes in the U-234, U-235, U-236, U-238, Pu-238, Pu-239, Pu-240, Pu-241, Pu-242, and Am-241 concentration with burnup are used in burnup credit criticality analyses. No credit for fission product neutron absorbers is taken. The methodology consists of five major steps. (1) Validate a computer code system to calculate isotopic concentrations of SNF created during burnup in the reactor core and subsequent decay. A set of chemical assay benchmarks is presented for this purpose as well as a method for assessing the calculational bias and uncertainty, and conservative correction factors for each isotope. (2) Validate a computer code system to predict the subcritical multiplication factor, k{sub eff}, of a spent nuclear fuel package. Fifty-seven UO{sub 2}, UO{sub 2}/Gd{sub 2}O{sub 3}, and UO{sub 2}/PuO{sub 2} critical experiments have been selected to cover anticipated conditions of SNF. The method uses an upper safety limit on k{sub eff} (which can be a function of the trending parameters) such that the biased k{sub eff}, when increased for the uncertainty is less than 0.95. (3) Establish bounding conditions for the isotopic concentration and criticality calculations. Three bounding axial profiles have been established to assure the ''end effect'' is accounted for conservatively. (4) Use the validated codes and bounding conditions to generate package loading criteria (burnup credit loading curves). Burnup credit loading curves show the minimum burnup required for a given initial enrichment. The utility burnup record is compared to this requirement after the utility accounts for the uncertainty in its record. Separate curves may be generated for each assembly design, various minimum cooling times and burnable absorber histories. (5) Verify that SNF assemblies meet the package

  5. Sodium void reactivity comparison for advanced liquid-metal reactor fuels

    Energy Technology Data Exchange (ETDEWEB)

    Dobbin, K.D.; Kessler, S.F.; Gedeon, S.R.; Omberg, R.P. (Westinghouse Hanford Co., Richland, WA (United States))

    1991-01-01

    The advanced liquid-metal reactor (ALMR) program in the US is based on metal as the reference fuel because of its favorable neutronic feedback characteristics for passive safety. Favorable relationships exist between core performance and safety that provide a passively safe metal fuel system with a large margin to sodium boiling. Because of this, the reduction of the positive sodium void coefficient of reactivity is not an overriding design objective. A positive sodium void effect with metal fuel is due to neutron spectral hardening that dominates capture and leakage changes during sodium voiding. This can produce as much as 5-$ positive sodium void reactivity for mixed plutonium-uranium fuel in a smaller core designed for a near-zero burnup reactivity swing. It is possible to reduce the positive void feedback and its effect on hypothetical loss-of-flow (LOF) scenarios with a commensurate increase in burnup swing. However, metal fuel's small Doppler coefficient, excellent fuel conductivity, and resultant small temperature gradients provide less reactivity feedback to handle postulated transient overpower (TOP) events for cores with significant burnup reactivity swings. The purpose of this work was to study the relationship between reduction of the sodium void and the resultant increase in the burnup reactivity swing for an ALMR modeled with metal, nitride, and oxide fuel.

  6. Photochemical modeling of emissions trading of highly reactive volatile organic compounds in Houston, Texas. 1. Reactivity based trading and potential for ozone hot spot formation.

    Science.gov (United States)

    Wang, Linlin; Thompson, Tammy; McDonald-Buller, Elena C; Webb, Alba; Allen, David T

    2007-04-01

    As part of the State Implementation Plan for attaining the National Ambient Air Quality Standard for ozone, the Texas Commission of Environmental Quality has created a Highly Reactive Volatile Organic Compounds (HRVOC) Emissions Cap and Trade Program for industrial point sources in the Houston/Galveston/Brazoria area. This program has a number of unique features, including its focus on a limited group of ozone precursors and its provisions for trading emissions based on atmospheric reactivity. This series of papers examines the potential air quality impacts of this new emission trading program through photochemical modeling of potential trading scenarios; this first paper in the series describes the air quality modeling methods used to assess potential trades, the potential for localized increases in ozone concentrations (ozone "hot spots") due to HRVOC emission trading, and the use of reactivity scales in the trading. When HRVOC emissions are traded on a mass basis, the simulations indicate that trading of HRVOC allowances between facilities resulted in less than 0.15 ppb (ozone concentrations, respectively. Maximum decreases in ozone concentrations associated with trading, as opposed to across-the-board reductions, were larger than the increases. All of these changes are small compared to the maximum changes in ozone concentrations due to the VOC emissions from these sources (up to 5-10 ppb for 8 h averages; up to 30 ppb for 1-h averages). When emissions of HRVOCs are traded for other, less reactive emissions, on a reactivity weighted basis, air quality simulations indicate that daily maximum ozone concentrations increased by less than 0.3%. Because these relatively small changes (ozone concentrations (all emissions traded into localized regions), the simulations indicate that the implementation of the trading program, as currently configured and possibly expanded, is unlikely to cause localized increases in ozone concentrations ("hot spots").

  7. High risk of cross-reactivity between vancomycin and sequential teicoplanin therapy.

    Science.gov (United States)

    Hsiao, S-H; Chou, C-H; Lin, W-L; Lee, E-J; Liao, L-H; Chang, H-J; Yeh, P-Y; Lin, C-Y; Wu, T-J

    2012-06-01

    Teicoplanin and vancomycin show similar clinical and bacteriological efficacy in clinical trials. Teicoplanin has been reported to have a lower adverse drug reaction (ADR) rate than vancomycin. Cross-reactivity between these two glycopeptides is controversial. Our aim was to study the cross-reactivity between teicoplanin and vancomycin through an assessment of all the reported ADRs of these drugs in our University hospital. Over a period of 2 years, 170 cases of vancomycin therapy, which were closely monitored by doctors and clinical pharmacists, were used to analyse ADRs. Teicoplanin therapy was used as an alternative in cases of vancomycin intolerance. When an ADR related to vancomycin or teicoplanin was suspected, specialists were consulted to confirm if these were true ADR and to determine whether the implicated drug should be stopped. All ADRs for the two glycopeptides were assessed for causality using the Naranjo probability scale. Thirty-eight of 170 patients (22·4%) treated with vancomycin developed ADRs. Twenty-four patients were switched to teicoplanin. However, 14 of those 24 patients (58·3%) developed ADRs. The time of onset of ADRs involving vancomycin was 12·7 ± 10·9 days (range, 1-46 days). The time of onset of sequential teicoplanin-induced ADRs was 11·7 ± 4·7 days (range, 2-20 days). Of the 14 patients with ADRs related to sequential teicoplanin therapy, six showed cross-reactivity between vancomycin and teicoplanin. The incidence of vancomycin-induced neutropenia was 4·7% (8/170), whereas the incidence of teicoplanin-induced neutropenia subsequent to vancomycin intolerance was as high as 33·3% (8/24). Furthermore, 71·4% (10/14) of the teicoplanin-induced ADRs were associated with haematological abnormalities such as neutropenia, thrombocytopenia or leucopenia. Teicoplanin, used as an alternative in cases of vancomycin intolerance, was associated with a high incidence of ADRs and haematological reactions, most notably neutropenia. This

  8. Affective and neural reactivity to criticism in individuals high and low on perceived criticism.

    Directory of Open Access Journals (Sweden)

    Jill M Hooley

    Full Text Available People who have remitted from depression are at increased risk for relapse if they rate their relatives as being critical of them on a simple self-report measure of Perceived Criticism (PC. To explore neural mechanisms associated with this we used functional magnetic resonance imaging (fMRI to examine how people with different levels of PC responded to hearing criticism from their own mothers. To maximize variability in affective reactivity, depressed, recovered depressed, and healthy control participants (n = 33 were classified as high or low in PC based on a median split. They were then exposed to personally-relevant critical and praising comments from their mothers. Perceived Criticism levels were unrelated to depression status and to negative mood change after hearing criticism. However, compared to low PC participants, those who scored high on PC showed differential activation in a network of regions associated with emotion reactivity and regulation, including increased amygdala activity and decreased reactions in prefrontal regulatory regions when they heard criticism. This was not the case for praise. Criticism may be a risk factor for relapse because it helps to "train" pathways characteristic of depressive information processing. The Perceived Criticism measure may help identify people who are more susceptible to this vulnerability.

  9. Brain reactivity differentiates subjects with high and low dream recall frequencies during both sleep and wakefulness.

    Science.gov (United States)

    Eichenlaub, Jean-Baptiste; Bertrand, Olivier; Morlet, Dominique; Ruby, Perrine

    2014-05-01

    The neurophysiological correlates of dreaming remain unclear. According to the "arousal-retrieval" model, dream encoding depends on intrasleep wakefulness. Consistent with this model, subjects with high and low dream recall frequency (DRF) report differences in intrasleep awakenings. This suggests a possible neurophysiological trait difference between the 2 groups. To test this hypothesis, we compared the brain reactivity (evoked potentials) of subjects with high (HR, N = 18) and low (LR, N = 18) DRF during wakefulness and sleep. During data acquisition, the subjects were presented with sounds to be ignored (first names randomly presented among pure tones) while they were watching a silent movie or sleeping. Brain responses to first names dramatically differed between the 2 groups during both sleep and wakefulness. During wakefulness, the attention-orienting brain response (P3a) and a late parietal response were larger in HR than in LR. During sleep, we also observed between-group differences at the latency of the P3a during N2 and at later latencies during all sleep stages. Our results demonstrate differences in the brain reactivity of HR and LR during both sleep and wakefulness. These results suggest that the ability to recall dreaming is associated with a particular cerebral functional organization, regardless of the state of vigilance.

  10. Effects of microstructural constraints on the transport of fission products in uranium dioxide at low burnups

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Harn Chyi; Rudman, Karin; Krishnan, Kapil; McDonald, Robert [Arizona State University, Tempe, AZ (United States); Dickerson, Patricia [Los Alamos National Lab, Los Alamos, NM (United States); Gong, Bowen [Arizona State University, Tempe, AZ (United States); Peralta, Pedro, E-mail: pperalta@asu.edu [Arizona State University, Tempe, AZ (United States)

    2016-08-15

    Diffusion of fission gases in UO{sub 2} is studied at low burnups, before bubble growth and coalescence along grain boundaries (GBs) become dominant, using a 3-D finite element model that incorporates actual UO{sub 2} microstructures. Grain boundary diffusivities are assigned based on crystallography with lattice and GB diffusion coupled with temperature to account for temperature gradients. Heterogeneity of GB properties and connectivity can induce regions where concentration is locally higher than without GB diffusion. These regions are produced by “bottlenecks” in the GB network because of lack of connectivity among high diffusivity GBs due to crystallographic constraints, and they can lead to localized swelling. Effective diffusivities were calculated assuming a uniform distribution of high diffusivity among GBs. Results indicate an increase over the bulk diffusivity with a clear grain size effect and that connectivity and properties of different GBs become important factors on the variability of fission product concentration at the microscale. - Highlights: • Microstructure models are developed to study fission gas transport in oxide fuels. • Crystallographic and temperature dependent material properties are applied. • Fission product concentration is affected by grain boundary distribution. • High concentration regions can form as controlled by the grain boundary connectivity.

  11. Reactive powder concrete reinforced with steel fibres exposed to high temperatures

    Science.gov (United States)

    Alrekabi, T. Kh; Cunha, V. M. C. F.; Barros, J. A. O.

    2017-09-01

    An experimental investigation was carried out to assess the mechanical properties of reactive powder concrete (RPC) reinforced with steel fibres (2% in vol.) when exposed to high temperatures. The compressive, flexural and tensile strength, modulus of elasticity and post-cracking behaviour were assessed after specimens’ exposure to different high temperatures ranging from 400 to 700°C. The mechanical properties of the RPC were assessed for specimens dried for 24 hours at 60 °C and 100 °C. Partially dried specimens (60 °C) exhibited explosive spalling at nearby 450 °C, while fully dried RPC specimens (100 °C) maintained their integrity after heating exposure. In general, the mechanical properties of RPC significantly decreased with the increase of the temperature exposure. The rate of decrease with temperature of the compressive, tensile and flexural strengths, as well the corresponding post-cracking residual stresses was higher for exposure temperatures above the 400 °C.

  12. Low-Temperature Production of Genuinely Amorphous Carbon from Highly Reactive Nanoacetylide Precursors

    Directory of Open Access Journals (Sweden)

    Ken Judai

    2016-01-01

    Full Text Available Copper acetylide is a well-known explosive compound. However, when the size of it crystals is reduced to the nanoscale, its explosive nature is lost, owing to a much lower thermal conductance that inhibits explosive chain reactions. This less explosive character can be exploited for the production of new carbon materials. Generally, amorphous carbon is prepared by carbonization of organic compounds exposed to high temperature, which can induce partial crystallization in graphite. In this work, we present a new method in which the carbonization reaction can proceed at a lower annealing temperature (under 150°C owing to the highly reactive nature of copper acetylide, thus avoiding crystallization processes and enabling the production of genuinely amorphous carbon materials.

  13. Ice sheets as a significant source of highly reactive nanoparticulate iron to the oceans.

    Science.gov (United States)

    Hawkings, Jon R; Wadham, Jemma L; Tranter, Martyn; Raiswell, Rob; Benning, Liane G; Statham, Peter J; Tedstone, Andrew; Nienow, Peter; Lee, Katherine; Telling, Jon

    2014-05-21

    The Greenland and Antarctic Ice Sheets cover ~ 10% of global land surface, but are rarely considered as active components of the global iron cycle. The ocean waters around both ice sheets harbour highly productive coastal ecosystems, many of which are iron limited. Measurements of iron concentrations in subglacial runoff from a large Greenland Ice Sheet catchment reveal the potential for globally significant export of labile iron fractions to the near-coastal euphotic zone. We estimate that the flux of bioavailable iron associated with glacial runoff is 0.40-2.54 Tg per year in Greenland and 0.06-0.17 Tg per year in Antarctica. Iron fluxes are dominated by a highly reactive and potentially bioavailable nanoparticulate suspended sediment fraction, similar to that identified in Antarctic icebergs. Estimates of labile iron fluxes in meltwater are comparable with aeolian dust fluxes to the oceans surrounding Greenland and Antarctica, and are similarly expected to increase in a warming climate with enhanced melting.

  14. Trapping a Highly Reactive Nonheme Iron Intermediate That Oxygenates Strong C-H Bonds with Stereoretention.

    Science.gov (United States)

    Serrano-Plana, Joan; Oloo, Williamson N; Acosta-Rueda, Laura; Meier, Katlyn K; Verdejo, Begoña; García-España, Enrique; Basallote, Manuel G; Münck, Eckard; Que, Lawrence; Company, Anna; Costas, Miquel

    2015-12-23

    An unprecedentedly reactive iron species (2) has been generated by reaction of excess peracetic acid with a mononuclear iron complex [Fe(II)(CF3SO3)2(PyNMe3)] (1) at cryogenic temperatures, and characterized spectroscopically. Compound 2 is kinetically competent for breaking strong C-H bonds of alkanes (BDE ≈ 100 kcal·mol(-1)) through a hydrogen-atom transfer mechanism, and the transformations proceed with stereoretention and regioselectively, responding to bond strength, as well as to steric and polar effects. Bimolecular reaction rates are at least an order of magnitude faster than those of the most reactive synthetic high-valent nonheme oxoiron species described to date. EPR studies in tandem with kinetic analysis show that the 490 nm chromophore of 2 is associated with two S = 1/2 species in rapid equilibrium. The minor component 2a (∼5% iron) has g-values at 2.20, 2.19, and 1.99 characteristic of a low-spin iron(III) center, and it is assigned as [Fe(III)(OOAc)(PyNMe3)](2+), also by comparison with the EPR parameters of the structurally characterized hydroxamate analogue [Fe(III)(tBuCON(H)O)(PyNMe3)](2+) (4). The major component 2b (∼40% iron, g-values = 2.07, 2.01, 1.95) has unusual EPR parameters, and it is proposed to be [Fe(V)(O)(OAc)(PyNMe3)](2+), where the O-O bond in 2a has been broken. Consistent with this assignment, 2b undergoes exchange of its acetate ligand with CD3CO2D and very rapidly reacts with olefins to produce the corresponding cis-1,2-hydroxoacetate product. Therefore, this work constitutes the first example where a synthetic nonheme iron species responsible for stereospecific and site selective C-H hydroxylation is spectroscopically trapped, and its catalytic reactivity against C-H bonds can be directly interrogated by kinetic methods. The accumulated evidence indicates that 2 consists mainly of an extraordinarily reactive [Fe(V)(O)(OAc)(PyNMe3)](2+) (2b) species capable of hydroxylating unactivated alkyl C-H bonds with

  15. Tuberculin reactivity in a population of schoolchildren with high BCG vaccination coverage

    Directory of Open Access Journals (Sweden)

    Bierrenbach Ana L.

    2003-01-01

    Full Text Available OBJECTIVE: To investigate the influence of BCG vaccination or revaccination on tuberculin skin test reactivity, in order to guide the correct interpretation of this test in a setting of high neonatal BCG vaccination coverage and an increasing BCG revaccination coverage at school age. METHODS: We conducted tuberculin skin testing and BCG scar reading in 1148 children aged 7-14 years old in the city of Salvador, Bahia, Brazil. We measured the positive effect of the presence of one or two BCG scars on the proportion of tuberculin skin test results above different cut-off levels (induration sizes of > 5 mm, > 10 mm, and > 15 mm and also using several ranges of induration size (0, 1-4, 5-9, 10-14, and > 15 mm. We also measured the effects that age, gender, and the school where the child was enrolled had on these proportions. RESULTS: The proportion of tuberculin results > 10 mm was 14.2% (95% confidence interval (CI = 8.0%-20.3% for children with no BCG scar, 21.3% (95% CI = 18.5%-24.1% for children with one BCG scar, and 45.0% (95% CI = 32.0%-58.0% for children with two BCG scars. There was evidence for an increasing positive effect of the presence of one and two BCG scars on the proportion of results > 5 mm and > 10 mm. Similarly, there was evidence for an increasing positive effect of the presence of one and two scars on the proportion of tuberculin skin test results in the ranges of 5-9 mm and of 10-14 mm. The BCG scar effect on the proportion of results > 5 mm and > 10 mm did not vary with age. There was no evidence for BCG effect on the results > 15 mm. CONCLUSIONS: In Brazilian schoolchildren, BCG-induced tuberculin reactivity is indistinguishable, for results under 15 mm, from reactivity induced by Mycobacterium tuberculosis infection. BCG revaccination at school age increases the degree of BCG-induced tuberculin reactivity found among schoolchildren. This information should be taken into account in tuberculin skin test surveys intended to

  16. Hysteresis-free high rate reactive sputtering of niobium oxide, tantalum oxide, and aluminum oxide

    Energy Technology Data Exchange (ETDEWEB)

    Särhammar, Erik, E-mail: erik.sarhammar@angstrom.uu.se; Berg, Sören; Nyberg, Tomas [Department of Solid State Electronics, The Ångström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala (Sweden)

    2014-07-01

    This work reports on experimental studies of reactive sputtering from targets consisting of a metal and its oxide. The composition of the targets varied from pure metal to pure oxide of Al, Ta, and Nb. This combines features from both the metal target and oxide target in reactive sputtering. If a certain relation between the metal and oxide parts is chosen, it may be possible to obtain a high deposition rate, due to the metal part, and a hysteresis-free process, due to the oxide part. The aim of this work is to quantify the achievable boost in oxide deposition rate from a hysteresis-free process by using a target consisting of segments of a metal and its oxide. Such an increase has been previously demonstrated for Ti using a homogeneous substoichiometric target. The achievable gain in deposition rate depends on transformation mechanisms from oxide to suboxides due to preferential sputtering of oxygen. Such mechanisms are different for different materials and the achievable gain is therefore material dependent. For the investigated materials, the authors have demonstrated oxide deposition rates that are 1.5–10 times higher than what is possible from metal targets in compound mode. However, although the principle is demonstrated for oxides of Al, Ta, and Nb, a similar behavior is expected for most oxides.

  17. Burnup simulations and spent fuel characteristics of ZrO 2 based inert matrix fuels

    Science.gov (United States)

    Schneider, E. A.; Deinert, M. R.; Herring, S. T.; Cady, K. B.

    2007-03-01

    Reducing the inventory of long lived isotopes that are contained in spent nuclear fuel is essential for maximizing repository capacity and extending the lifetime of related storage. Because of their non-fertile matrices, inert matrix fuels (IMF's) could be an ideal vehicle for using light-water reactors to help decrease the inventory of plutonium and other transuranics (neptunium, americium, curium) that are contained within spent uranium oxide fuel (UOX). Quantifying the characteristics of spent IMF is therefore of fundamental importance to determining its effect on repository design and capacity. We consider six ZrO 2 based IMF formulations with different transuranic loadings in a 1-8 IMF to UOX pin-cell arrangement. Burnup calculations are performed using a collision probability model where transport of neutrons through space is modeled using fuel to moderator transport and escape probabilities. The lethargy dependent neutron flux is treated with a high resolution multigroup thermalization method. The results of the reactor physics model are compared to a benchmark case performed with Montebruns and indicate that the approach yields reliable results applicable to high-level analyses of spent fuel isotopics. The data generated show that a fourfold reduction in the radiological and integrated thermal output is achievable in single recycle using IMF, as compared to direct disposal of an energy equivalent spent UOX.

  18. Burnup calculations using the OREST computer code for uranium dioxide fuel elements of boiling water reactors. Abbrandberechnung mit OREST fuer Urandioxid-Siedewasserreaktor-Brennelemente

    Energy Technology Data Exchange (ETDEWEB)

    Hesse, U.

    1991-01-01

    There are plans to also use plutonium containing fuel elements (mixed oxide fuel) in the BWR type reactors, with a proportion of up to one third of the entire fuel core. The new concept uses complete MOX fuel elements, as are used in the PWR type reactors. The OREST computer code has been designed for burnup calculations in PWRs. The situation in BWRs is different, as in these reactor types, fuel elements are heterogenous in design, and burnup calculations have to take into account the axial variations of the void fraction, so that multi-dimensional effects have to be calculated. The report explains that the one-dimensional OREST code can be enhanced by supplementing calculations, performed with the Monte-Carlo type KENO code in this case, and is thus suitable without restrictions for performing burnup calculations for MOX fuel elements in BWRs. The calculation method and performance is illustrated by the example of a UO{sub 2} fuel element of the Wuergassen reactor. The model calculations predict a relatively high residual activity in the upper part of the fuel element, and a distinct curium buildup in the lower third of the BWR fuel element. (orig./HP).

  19. Dysregulation in cortical reactivity to emotional faces in PTSD patients with high dissociation symptoms

    Directory of Open Access Journals (Sweden)

    Aleksandra Klimova

    2013-09-01

    Full Text Available Background: Predominant dissociation in posttraumatic stress disorder (PTSD is characterized by restricted affective responses to positive stimuli. To date, no studies have examined neural responses to a range of emotional expressions in PTSD with high dissociative symptoms. Objective: This study tested the hypothesis that PTSD patients with high dissociative symptoms will display increased event-related potential (ERP amplitudes in early components (N1, P1 to threatening faces (angry, fearful, and reduced later ERP amplitudes (Vertex Positive Potential (VPP, P3 to happy faces compared to PTSD patients with low dissociative symptoms. Methods: Thirty-nine civilians with PTSD were classified as high dissociative (n=16 or low dissociative (n=23 according to their responses on the Clinician Administered Dissociative States Scale. ERPs were recorded, whilst participants viewed emotional (happy, angry, fear and neutral facial expressions in a passive viewing task. Results: High dissociative PTSD patients displayed significantly increased N120 amplitude to the majority of facial expressions (neutral, happy, and angry compared to low dissociative PTSD patients under conscious and preconscious conditions. The high dissociative PTSD group had significantly reduced VPP amplitude to happy faces in the conscious condition. Conclusion: High dissociative PTSD patients displayed increased early (preconscious cortical responses to emotional stimuli, and specific reductions to happy facial expressions in later (conscious, face-specific components compared to low dissociative PTSD patients. Dissociation in PTSD may act to increase initial pre-attentive processing of affective stimuli, and specifically reduce cortical reactivity to happy faces when consciously processing these stimuli.

  20. Evidence for Different Reactive Hg Sources and Chemical Compounds at Adjacent Valley and High Elevation Locations.

    Science.gov (United States)

    Sexauer Gustin, Mae; Pierce, Ashley M; Huang, Jiaoyan; Miller, Matthieu B; Holmes, Heather A; Loria-Salazar, S Marcela

    2016-11-15

    The spatial distribution of chemical compounds and concentration of reactive mercury (RM), defined as the sum of gaseous oxidized mercury (GOM) and sources (GOM = nitrogen and sulfur-based compounds), and the high elevation site (GOM = halogen-based compounds) was affected by long-range transport in the free troposphere over the marine boundary layer into Nevada. Data collected at these two locations demonstrate that different GOM compounds exist depending on the oxidants present in the air. Measurements of GOM made by the KCl denuder in the Tekran instrument located at the low elevation site were lower than that measured using membranes by 1.7-13 times. Accurate measurements of atmospheric concentrations and chemistry of RM are necessary for proper assessment of environmental impacts, and field measurements are essential for atmospheric models, which in turn influence policy decisions.

  1. Cardiovascular risk assessment using high-sensitivity C-reactive protein in patients with erectile dysfunction.

    Science.gov (United States)

    Ferrandis-Cortes, Cristina; Martínez-Jabaloyas, José M; Díez-Calzadilla, Nelson A; Hernández-Medina, José A; Chuan-Nuez, Pascual

    2013-01-01

    Erectile dysfunction (ED) is associated with cardiovascular events. High-sensitivity C-reactive protein (hsCRP) is a cardiovascular risk marker. The aim of this study is to determine whether hsCRP is useful in evaluating ED. In 121 patients with ED, age, ED type and severity, time since onset of ED, weight, height, BMI, body fat percentage, waist and hip circumference, hsCRP and hormone profile were studied. Patients were classified as low or moderate-high cardiovascular risk based on hsCRP levels. A descriptive and univariate study was performed. A logistic regression was used to establish factors associated with low versus moderate-high cardiovascular risk and hsCRP. Most patients had moderate-severe ED (70%). 74% had a moderate-high cardiovascular risk based on hsCRP levels, and 33.9 and 34.7% had hypogonadism according to total (TT) and free testosterone. In the univariate analysis, a relationship between hsCRP and TT and physical examination variables was observed (p cardiovascular risk was found in the hypogonadic group (OR: 5.51; 95% CI: 1.185-25.662) and waist- to-hip ratio (p = 0.008; OR: 1.361; 95% CI: 1.075-1.612). A majority of patients with ED have high cardiovascular risk based on hsCRP levels and there is an association with hypogonadism and obesity. © 2013 S. Karger AG, Basel.

  2. Oxygen pathway modeling estimates high reactive oxygen species production above the highest permanent human habitation.

    Directory of Open Access Journals (Sweden)

    Isaac Cano

    Full Text Available The production of reactive oxygen species (ROS from the inner mitochondrial membrane is one of many fundamental processes governing the balance between health and disease. It is well known that ROS are necessary signaling molecules in gene expression, yet when expressed at high levels, ROS may cause oxidative stress and cell damage. Both hypoxia and hyperoxia may alter ROS production by changing mitochondrial Po2 (PmO2. Because PmO2 depends on the balance between O2 transport and utilization, we formulated an integrative mathematical model of O2 transport and utilization in skeletal muscle to predict conditions to cause abnormally high ROS generation. Simulations using data from healthy subjects during maximal exercise at sea level reveal little mitochondrial ROS production. However, altitude triggers high mitochondrial ROS production in muscle regions with high metabolic capacity but limited O2 delivery. This altitude roughly coincides with the highest location of permanent human habitation. Above 25,000 ft., more than 90% of exercising muscle is predicted to produce abnormally high levels of ROS, corresponding to the "death zone" in mountaineering.

  3. MOX fuel characterization for burnup credit application: Extension of nondestructive method qualified for LEU fuels

    Energy Technology Data Exchange (ETDEWEB)

    Riffard, C.; Vidal, J.M. [Commissariat a l' Energie Atomique CEA/DEN/CAD, Building 230 Centre d tudes de Cadarache, 13108 St. Paul Lez Durance (France); Toubon, H. [COGEMA, 78 141 Velizy cedex (France); Pelletter, S. [Canberra-Eurisys, 78067 St. Quentin en Yvelines cedex (France); Batifol, M. [COGEMA La Hague, 50444 Beaumont Hague cedex (France)

    2006-07-01

    Before the reprocessing of low-enriched uranium (LEU) fuels at La. Hague plant, the assemblies are characterized with a nondestructive assay based on neutron emission (NE) and gamma-ray emission combined with the CESAR depletion code, giving the burnup (BU) with a good accuracy ({+-} 5% within a batch of fuels from one of COGEMA-La Hague's clients). The measurements confirm the hypothesis of the safety-criticality analysis of the process, in the context of the BU credit allowance. There is a need to extend the allowance of the reprocessing plants to the case of more highly enriched LEU fuels and to the case of mixed-oxide (MOX) fuels. The aim is to propose an upgraded method, valid for both LEU and MOX fuels, giving the average BU with an uncertainty lower than {+-} 15% for MOX fuels (without any modification of the current acceptance criteria for UO{sub 2} fuel, i.e. {+-} 15%), with a complementary module checking the operator data using the gamma-ray emission and the CESAR depletion code. In particular, the NE was interpreted with depletion calculations in the case of MOX fuels, which is the principal aim of this paper. This allows the BU determination of MOX fuels, which has been qualified during a measurement campaign in La Hague with 20 MOX assemblies. The mean BU of pressurized water reactor MOX assemblies has been determined for the first time with a maximum discrepancy of {+-} 5% compared to the declared value. (authors)

  4. Spent fuel pool storage calculations using the ISOCRIT burnup credit tool

    Energy Technology Data Exchange (ETDEWEB)

    Kucukboyaci, Vefa [Westinghouse Electric Company, Cranberry Township, PA; Marshall, William BJ J [ORNL

    2012-01-01

    In order to conservatively apply burnup credit in spent fuel pool criticality safety analyses, Westinghouse has developed a software tool, ISOCRIT, for generating depletion isotopics. This tool is used to create isotopics data based on specific reactor input parameters, such as design basis assembly type; bounding power/burnup profiles; reactor specific moderator temperature profiles; pellet percent theoretical density; burnable absorbers, axial blanket regions, and bounding ppm boron concentration. ISOCRIT generates burnup dependent isotopics using PARAGON; Westinghouse's state-of-the-art and licensed lattice physics code. Generation of isotopics and passing the data to the subsequent 3D KENO calculations are performed in an automated fashion, thus reducing the chance for human error. Furthermore, ISOCRIT provides the means for responding to any customer request regarding re-analysis due to changed parameters (e.g., power uprate, exit temperature changes, etc.) with a quick turnaround.

  5. Burn-up dependent steady-state thermal hydraulic analysis of Pakistan research reactor-1

    Directory of Open Access Journals (Sweden)

    Muhammad Atta

    2011-01-01

    Full Text Available The burn-up dependent steady-state thermal hydraulic analysis of Pakistan research reactor-1, reference operating core, has been carried out utilizing standard computer codes WIMS/D4, CITATION, and RELAP5/MOD3.4. Reactor codes WIMS/D4 and CITATION have been used for the calculations of neutronic parameters including peaking factors and power profiles at different burn-up considering a xenon free core and also the equilibrium xenon values. RELAP5/MOD3.4 code was utilized for the determination of peak fuel centerline, clad and coolant temperatures to ensure the safety of the reactor throughout the cycle. The calculations reveal that the reactor is safe and no nucleate boiling will commence at any part of the core throughout the cycle and that the safety margin increases with burnup as peaking factors decrease.

  6. An iterative approach for TRIGA fuel burn-up determination using nondestructive gamma-ray spectrometry.

    Science.gov (United States)

    Wang, T K; Peir, J J

    2000-01-01

    The purpose of this work is to establish a method for evaluating the burn-up values of the rod-type TRIGA spent fuel by using gamma-ray spectrometry of the short-lived fission products 97Zr/97Nb, 132I, and 140La. Fuel irradiation history is not needed in this method. Short-lived fission-product activities were established by reirradiating the spent fuels in a nuclear reactor. Based on the measured activities, 235U burn-up values can be deduced by iterative calculations. The complication caused by 239Pu production and fission is also discussed in detail. The burn-up values obtained by this method are in good agreement with those deduced from the conventional method based on long-lived fission products 137Cs, 134Cs/137Cs ratio and 106Ru/137Cs ratio.

  7. A high sensitivity assay for the inflammatory marker C-Reactive protein employing acoustic biosensing

    Directory of Open Access Journals (Sweden)

    Cooper Matthew A

    2008-04-01

    Full Text Available Abstract C-Reactive Protein (CRP is an acute phase reactant routinely used as a biomarker to assess either infection or inflammatory processes such as autoimmune diseases. CRP also has demonstrated utility as a predictive marker of future risk of cardiovascular disease. A new method of immunoassay for the detection of C-Reactive Protein has been developed using Resonant Acoustic Profiling™ (RAP™ with comparable sensitivity to a high sensitivity CRP ELISA (hsCRP but with considerable time efficiency (12 minutes turnaround time to result. In one method, standard solutions of CRP (0 to 231 ng/mL or diluted spiked horse serum sample are injected through two sensor channels of a RAP™ biosensor. One contains a surface with sheep antibody to CRP, the other a control surface containing purified Sheep IgG. At the end of a 5-minute injection the initial rate of change in resonant frequency was proportional to CRP concentration. The initial rates of a second sandwich step of anti-CRP binding were also proportional to the sample CRP concentration and provided a more sensitive method for quantification of CRP. The lower limit of detection for the direct assay and the homogenous sandwich assay were both 20 ng/mL whereas for the direct sandwich assay the lower limit was 3 ng/mL. In a step towards a rapid clinical assay, diluted horse blood spiked with human CRP was passed over one sensor channel whilst a reference standard solution at the borderline cardiovascular risk level was passed over the other. A semi-quantities ratio was thus obtained indicative of sample CRP status. Overall, the present study revealed that CRP concentrations in serum that might be expected in both normal and pathological conditions can be detected in a time-efficient, label-free immunoassay with RAP™ detection technology with determined CRP concentrations in close agreement with those determined using a commercially available high sensitivity ELISA.

  8. Addressing Fission Product Validation in MCNP Burnup Credit Criticality Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Don [ORNL; Bowen, Douglas G [ORNL; Marshall, William BJ J [ORNL

    2015-01-01

    The US Nuclear Regulatory Commission (NRC) Division of Spent Fuel Storage and Transportation issued Interim Staff Guidance (ISG) 8, Revision 3 in September 2012. This ISG provides guidance for NRC staff members’ review of burnup credit (BUC) analyses supporting transport and dry storage of pressurized water reactor spent nuclear fuel (SNF) in casks. The ISG includes guidance for addressing validation of criticality (keff) calculations crediting the presence of a limited set of fission products and minor actinides (FP&MAs). Based on previous work documented in NRC Regulatory Guide (NUREG) Contractor Report (CR)-7109, the ISG recommends that NRC staff members accept the use of either 1.5 or 3% of the FP&MA worth—in addition to bias and bias uncertainty resulting from validation of keff calculations for the major actinides in SNF—to conservatively account for the bias and bias uncertainty associated with the specified unvalidated FP&MAs. The ISG recommends (1) use of 1.5% of the FP&MA worth if a modern version of SCALE and its nuclear data are used and (2) 3% of the FP&MA worth for well qualified, industry standard code systems other than SCALE with the Evaluated Nuclear Data Files, Part B (ENDF/B),-V, ENDF/B-VI, or ENDF/B-VII cross sections libraries. The work presented in this paper provides a basis for extending the use of the 1.5% of the FP&MA worth bias to BUC criticality calculations performed using the Monte Carlo N-Particle (MCNP) code. The extended use of the 1.5% FP&MA worth bias is shown to be acceptable by comparison of FP&MA worths calculated using SCALE and MCNP with ENDF/B-V, -VI, and -VII–based nuclear data. The comparison supports use of the 1.5% FP&MA worth bias when the MCNP code is used for criticality calculations, provided that the cask design is similar to the hypothetical generic BUC-32 cask model and that the credited FP&MA worth is no more than 0.1 Δkeff (ISG-8, Rev. 3, Recommendation 4).

  9. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  10. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason M.; Demkowicz, Paul A.; Stempien, John D.

    2016-11-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  11. Emotional Reactivity, Behavior Problems, and Social Adjustment at School Entry in a High-risk Sample.

    Science.gov (United States)

    Kalvin, Carla B; Bierman, Karen L; Gatzke-Kopp, Lisa M

    2016-11-01

    Prior research suggests that heightened emotional reactivity to emotionally distressing stimuli may be associated with elevated internalizing and externalizing behaviors, and contribute to impaired social functioning. These links were explored in a sample of 169 economically-disadvantaged kindergarteners (66 % male; 68 % African American, 22 % Hispanic, 10 % Caucasian) oversampled for elevated aggression. Physiological measures of emotional reactivity (respiratory sinus arrhythmia [RSA], heart rate [HR], and cardiac pre-ejection period [PEP]) were collected, and teachers and peers provided ratings of externalizing and internalizing behavior, prosocial competence, and peer rejection. RSA withdrawal, HR reactivity, and PEP shortening (indicating increased arousal) were correlated with reduced prosocial competence, and RSA withdrawal and HR reactivity were correlated with elevated internalizing problems. HR reactivity was also correlated with elevated externalizing problems and peer rejection. Linear regressions controlling for age, sex, race, verbal proficiency, and resting physiology showed that HR reactivity explained unique variance in both teacher-rated prosocial competence and peer rejection, and contributed indirectly to these outcomes through pathways mediated by internalizing and externalizing problems. A trend also emerged for the unique contribution of PEP reactivity to peer-rated prosocial competence. These findings support the contribution of emotional reactivity to behavior problems and social adjustment among children living in disadvantaged urban contexts, and further suggest that elevated reactivity may confer risk for social difficulties in ways that overlap only partially with internalizing and externalizing behavior problems.

  12. NUCLEAR DATA UNCERTAINTY PROPAGATION FOR A TYPICAL PWR FUEL ASSEMBLY WITH BURNUP

    Directory of Open Access Journals (Sweden)

    D. ROCHMAN

    2014-06-01

    Full Text Available The effects of nuclear data uncertainties are studied on a typical PWR fuel assembly model in the framework of the OECD Nuclear Energy Agency UAM (Uncertainty Analysis in Modeling expert working group. The “Fast Total Monte Carlo” method is applied on a model for the Monte Carlo transport and burnup code SERPENT. Uncertainties on k∞, reaction rates, two-group cross sections, inventory and local pin power density during burnup are obtained, due to transport cross sections for the actinides and fission products, fission yields and thermal scattering data.

  13. Fuel burnup calculation of Ghana MNSR using ORIGEN2 and REBUS3 codes.

    Science.gov (United States)

    Abrefah, R G; Nyarko, B J B; Fletcher, J J; Akaho, E H K

    2013-10-01

    Ghana Research Reactor-1 core is to be converted from HEU fuel to LEU fuel in the near future and managing the spent nuclear fuel is very important. A fuel depletion analysis of the GHARR-1 core was performed using ORIGEN2 and REBUS3 codes to estimate the isotopic inventory at end-of-cycle in order to help in the design of an appropriate spent fuel cask. The results obtained for both codes were consistent for U-235 burnup weight percent and Pu-239 build up as a result of burnup. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. High platelet reactivity on aspirin in patients with acute ST elevation myocardial infarction.

    Science.gov (United States)

    Dillinger, Jean-Guillaume; Saeed, Alaa; Spagnoli, Vincent; Sollier, Claire Bal Dit; Sideris, Georgios; Silberman, Stephane Manzo; Voicu, Sebastian; Drouet, Ludovic; Henry, Patrick

    2016-08-01

    Despite dual antiplatelet treatment, major ischemic events are common following ST elevation myocardial infarction (STEMI). We aimed to assess high platelet reactivity on aspirin (HPR-aspirin) and its association with P2Y12i (HPR-P2Y12i) during the acute phase of STEMI. We included all consecutive patients admitted for STEMI treated by primary angioplasty in our center for 1year. All patients received a loading dose followed by a maintenance dose of aspirin (75mg/day) and prasugrel (ticagrelor or clopidogrel if contraindicated). Platelet reactivity was assessed 4±1days and 75±15days after admission using light transmission aggregometry with arachidonic acid (LTA-AA-HPR-aspirin) and VASP (HPR-P2Y12i) to define HPR as well as serum Thromboxane-B2 and LTA-ADP. Major cardiac and cerebrovascular events were recorded for 1year. We included 106 patients - mean age was 61y.o., 76% were male and 20% had diabetes. STEMI was anterior in 52% and LV ejection fraction at discharge was 51±9%. 50% of patients were treated with prasugrel and 34% with ticagrelor. At day 4 after STEMI, HPR-aspirin was found in 26% patients and HPR-P2Y12i in 7%. HPR- both aspirin and P2Y12i was found in 4%. Diabetes and age were predictors of HPR-aspirin. HPR-aspirin was persistent 75days later in 36% patients. At 1year, 7.9% patients had experienced major adverse cardiovascular and cerebrovascular events (MACCE). HPR-aspirin and HPR on both aspirin and P2Y12i were significantly associated with MACCE. HPR-aspirin is frequent just after STEMI and associated with MACCE especially when associated with HPR-P2Y12i. Copyright © 2016. Published by Elsevier Ltd.

  15. High-sensitivity C-reactive protein and risk of sepsis.

    Directory of Open Access Journals (Sweden)

    Henry E Wang

    Full Text Available Conventional C-reactive protein assays have been used to detect or guide the treatment of acute sepsis. The objective of this study was to determine the association between elevated baseline high-sensitivity C-reactive protein (hsCRP and the risk of future sepsis events.We studied data from 30,239 community dwelling, black and white individuals, age ≥45 years old enrolled in the REasons for Geographic and Racial Differences in Stroke (REGARDS cohort. Baseline hsCRP and participant characteristics were determined at the start of the study. We identified sepsis events through review of hospital records. Elevated hsCRP was defined as values >3.0 mg/L. Using Cox regression, we determined the association between elevated hsCRP and first sepsis event, adjusting for sociodemographic factors (age, sex, race, region, education, income, health behaviors (tobacco and alcohol use, chronic medical conditions (coronary artery disease, diabetes, dyslipidemia, hypertension, chronic kidney disease, chronic lung disease and statin use.Over the mean observation time of 5.7 years (IQR 4.5-7.1, 974 individuals experienced a sepsis event, and 11,447 (37.9% had elevated baseline hsCRP (>3.0 mg/L. Elevated baseline hsCRP was independently associated with subsequent sepsis (adjusted HR 1.56; 95% CI 1.36-1.79, adjusted for sociodemographics, health behaviors, chronic medical conditions and statin use.Elevated baseline hsCRP was associated with increased risk of future sepsis events. hsCRP may help to identify individuals at increased risk for sepsis.

  16. Thromboxane Formation Assay to Identify High On-Treatment Platelet Reactivity to Aspirin.

    Science.gov (United States)

    Mohring, Annemarie; Piayda, Kerstin; Dannenberg, Lisa; Zako, Saif; Schneider, Theresa; Bartkowski, Kirsten; Levkau, Bodo; Zeus, Tobias; Kelm, Malte; Hohlfeld, Thomas; Polzin, Amin

    2017-01-01

    Platelet inhibition by aspirin is indispensable in the secondary prevention of cardiovascular events. Nevertheless, impaired aspirin antiplatelet effects (high on-treatment platelet reactivity [HTPR]) are frequent. This is associated with an enhanced risk of cardiovascular events. The current gold standard to evaluate platelet hyper-reactivity despite aspirin intake is the light-transmittance aggregometry (LTA). However, pharmacologically, the most specific test is the measurement of arachidonic acid (AA)-induced thromboxane (TX) B2 formation. Currently, the optimal cut-off to define HTPR to aspirin by inhibition of TX formation is not known. Therefore, in this pilot study, we aimed to calculate a TX formation cut-off value to detect HTPR defined by the current gold standard LTA. We measured platelet function in 2,507 samples. AA-induced TX formation by ELISA and AA-induced LTA were used to measure aspirin antiplatelet effects. TX formation correlated nonlinearly with the maximum of aggregation in the AA-induced LTA (Spearman's rho R = 0.7396; 95% CI 0.7208-0.7573, p < 0.0001). Receiver operating characteristic analysis and Youden's J statistics revealed 209.8 ng/mL as the optimal cut-off value to detect HTPR to aspirin with the TX ELISA (area under the curve: 0.92, p < 0.0001, sensitivity of 82.7%, specificity of 90.3%). In summary, TX formation ELISA is reliable in detecting HTPR to aspirin. The calculated cut-off level needs to be tested in trials with clinical end points. © 2017 S. Karger AG, Basel.

  17. Medical Image Retrieval with Compact Binary Codes Generated in Frequency Domain Using Highly Reactive Convolutional Features.

    Science.gov (United States)

    Ahmad, Jamil; Muhammad, Khan; Baik, Sung Wook

    2017-12-19

    Efficient retrieval of relevant medical cases using semantically similar medical images from large scale repositories can assist medical experts in timely decision making and diagnosis. However, the ever-increasing volume of images hinder performance of image retrieval systems. Recently, features from deep convolutional neural networks (CNN) have yielded state-of-the-art performance in image retrieval. Further, locality sensitive hashing based approaches have become popular for their ability to allow efficient retrieval in large scale datasets. In this paper, we present a highly efficient method to compress selective convolutional features into sequence of bits using Fast Fourier Transform (FFT). Firstly, highly reactive convolutional feature maps from a pre-trained CNN are identified for medical images based on their neuronal responses using optimal subset selection algorithm. Then, layer-wise global mean activations of the selected feature maps are transformed into compact binary codes using binarization of its Fourier spectrum. The acquired hash codes are highly discriminative and can be obtained efficiently from the original feature vectors without any training. The proposed framework has been evaluated on two large datasets of radiology and endoscopy images. Experimental evaluations reveal that the proposed method significantly outperforms other features extraction and hashing schemes in both effectiveness and efficiency.

  18. High-Sensitivity C-Reactive Protein as a Predictor of Cardiovascular Events after ST-Elevation Myocardial Infarction

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Daniel Rios Pinto; Ramos, Adriane Monserrat; Vieira, Pedro Lima; Menti, Eduardo; Bordin, Odemir Luiz Jr.; Souza, Priscilla Azambuja Lopes de; Quadros, Alexandre Schaan de; Portal, Vera Lúcia, E-mail: veraportal.pesquisa@gmail.com [Programa de Pós-Graduação em Ciências da Saúde: Cardiologia - Instituto de Cardiologia/Fundação Universitária de Cardiologia, Porto Alegre, RS (Brazil)

    2014-07-15

    The association between high-sensitivity C-reactive protein and recurrent major adverse cardiovascular events (MACE) in patients with ST-elevation myocardial infarction who undergo primary percutaneous coronary intervention remains controversial. To investigate the potential association between high-sensitivity C-reactive protein and an increased risk of MACE such as death, heart failure, reinfarction, and new revascularization in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention. This prospective cohort study included 300 individuals aged >18 years who were diagnosed with ST-elevation myocardial infarction and underwent primary percutaneous coronary intervention at a tertiary health center. An instrument evaluating clinical variables and the Thrombolysis in Myocardial Infarction (TIMI) and Global Registry of Acute Coronary Events (GRACE) risk scores was used. High-sensitivity C-reactive protein was determined by nephelometry. The patients were followed-up during hospitalization and up to 30 days after infarction for the occurrence of MACE. Student's t, Mann-Whitney, chi-square, and logistic regression tests were used for statistical analyses. P values of ≤0.05 were considered statistically significant. The mean age was 59.76 years, and 69.3% of patients were male. No statistically significant association was observed between high-sensitivity C-reactive protein and recurrent MACE (p = 0.11). However, high-sensitivity C-reactive protein was independently associated with 30-day mortality when adjusted for TIMI [odds ratio (OR), 1.27; 95% confidence interval (CI), 1.07-1.51; p = 0.005] and GRACE (OR, 1.26; 95% CI, 1.06-1.49; p = 0.007) risk scores. Although high-sensitivity C-reactive protein was not predictive of combined major cardiovascular events within 30 days after ST-elevation myocardial infarction in patients who underwent primary angioplasty and stent implantation, it was an independent predictor

  19. Shock compression response of highly reactive Ni + Al multilayered thin foils

    Science.gov (United States)

    Kelly, Sean C.; Thadhani, Naresh N.

    2016-03-01

    The shock-compression response of Ni + Al multilayered thin foils is investigated using laser-accelerated thin-foil plate-impact experiments over the pressure range of 2 to 11 GPa. The foils contain alternating Ni and Al layers (parallel but not flat) of nominally 50 nm bilayer spacing. The goal is to determine the equation of state and shock-induced reactivity of these highly reactive fully dense thin-foil materials. The laser-accelerated thin-foil impact set-up involved combined use of photon-doppler-velocimetry to monitor the acceleration and impact velocity of an aluminum flyer, and VISAR interferometry was used to monitor the back free-surface velocity of the impacted Ni + Al multilayered target. The shock-compression response of the Ni + Al target foils was determined using experimentally measured parameters and impedance matching approach, with error bars identified considering systematic and experimental errors. Meso-scale CTH shock simulations were performed using real imported microstructures of the cross-sections of the multilayered Ni + Al foils to compute the Hugoniot response (assuming no reaction) for correlation with their experimentally determined equation of state. It was observed that at particle velocities below ˜150 m/s, the experimentally determined equation of state trend matches the CTH-predicted inert response and is consistent with the observed unreacted state of the recovered Ni + Al target foils from this velocity regime. At higher particle velocities, the experimentally determined equation of state deviates from the CTH-predicted inert response. A complete and self-sustained reaction is also seen in targets recovered from experiments performed at these higher particle velocities. The deviation in the measured equation of state, to higher shock speeds and expanded volumes, combined with the observation of complete reaction in the recovered multilayered foils, confirmed via microstructure characterization, is indicative of the occurrence

  20. Subsurface multiphase flow and multicomponent reactive transport modeling using high-performance computing

    Science.gov (United States)

    Hammond, Glenn; Lichtner, Peter; Lu, Chuan

    2007-07-01

    Numerical modeling is a critical tool to the U.S. Department of Energy for evaluating the environmental impact of remediation strategies for subsurface legacy waste sites. Unfortunately, the physical and chemical complexity of many sites overwhelms the capabilities of even most state of the art groundwater models. Of particular concern is the representation of highly-heterogeneous stratified rock/soil layers in the subsurface and the biological and geochemical interactions of chemical species within multiple fluid phases. There is clearly a need for higher-resolution modeling (i.e. increased spatial and temporal resolution) and increasingly mechanistic descriptions of subsurface physicochemical processes (i.e. increased chemical degrees of freedom). We present SciDAC-funded research being performed in furthering the development of PFLOTRAN, a parallel multiphase flow and multicomponent reactive transport model. Written in Fortran90, PFLOTRAN is founded upon PETSc data structures and solvers. We are employing PFLOTRAN to simulate uranium transport at the Hanford 300 Area, a contaminated site of major concern to the Department of Energy, the State of Washington, and other government agencies. By leveraging the billions of degrees of freedom available through high-performance computation using tens of thousands of processors, we can better characterize the release of uranium into groundwater and its subsequent transport to the Columbia River, and thereby better understand and evaluate the effectiveness of various proposed remediation strategies.

  1. Nanoporous Hybrid Electrolytes for High-Energy Batteries Based on Reactive Metal Anodes

    KAUST Repository

    Tu, Zhengyuan

    2017-01-06

    Successful strategies for stabilizing electrodeposition of reactive metals, including lithium, sodium, and aluminum are a requirement for safe, high-energy electrochemical storage technologies that utilize these metals as anodes. Unstable deposition produces high-surface area dendritic structures at the anode/electrolyte interface, which causes premature cell failure by complex physical and chemical processes that have presented formidable barriers to progress. Here, it is reported that hybrid electrolytes created by infusing conventional liquid electrolytes into nanoporous membranes provide exceptional ability to stabilize Li. Electrochemical cells based on γ-Al2O3 ceramics with pore diameters below a cut-off value above 200 nm exhibit long-term stability even at a current density of 3 mA cm−2. The effect is not limited to ceramics; similar large enhancements in stability are observed for polypropylene membranes with less monodisperse pores below 450 nm. These findings are critically assessed using theories for ion rectification and electrodeposition reactions in porous solids and show that the source of stable electrodeposition in nanoporous electrolytes is fundamental.

  2. Cerebral vasomotor reactivity and apnea test in symptomatic and asymptomatic high-grade carotid stenosis

    Directory of Open Access Journals (Sweden)

    Lučić-Prokin Aleksandra

    2015-01-01

    Full Text Available Introduction. Cerebral vasomotor reactivity (VMR represents an autoregulatory response of the arterial trunks on the specific vasoactive stimuli, most commonly CO2. Objective. The aim of this retrospective study was to compare VMR in high-grade symptomatic (SCAS and asymptomatic carotid stenosis (ACAS, using the apnea test to evaluate the hemodynamic status. Methods. The study included 50 patients who were hospitalized at the neurology and vascular surgery departments as part of preparation for carotid endarterectomy. We evaluated VMR by calculating the breath holding index (BHI in 34 patients with SCAS and 16 patients with ACAS, with isolated high-grade carotid stenosis. We evaluated the impact of risk factors and collateral circulation on BHI, as well as the correlation between the degree of carotid stenosis and BHI. Results. A pathological BHI was more frequent in the SCAS group (p<0.01. There was no difference in the range of BHI values between the groups, both ipsilaterally and contralaterally. Only male gender was associated with pathological BHI in both groups (p<0.05. Collateral circulation did not exist in over 60% of all subjects. We confirmed a negative correlation between the degree of carotid stenosis and BHI. Conclusion. SCAS and ACAS patients present with different hemodynamics. While ACAS patients have stable hemodynamics, combination of hemodynamic and thromboembolic effects is characteristic of SCAS patients.

  3. Additive Manufacturing of Reactive In Situ Zr Based Ultra-High Temperature Ceramic Composites

    Science.gov (United States)

    Sahasrabudhe, Himanshu; Bandyopadhyay, Amit

    2016-03-01

    Reactive in situ multi-material additive manufacturing of ZrB2-based ultra-high-temperature ceramics in a Zr metal matrix was demonstrated using LENS™. Sound metallurgical bonding was achieved between the Zr metal and Zr-BN composites with Ti6Al4V substrate. Though the feedstock Zr power had α phase, LENS™ processing of the Zr powder and Zr-BN premix powder mixture led to the formation of some β phase of Zr. Microstructure of the Zr-BN composite showed primary grains of zirconium diboride phase in zirconium metal matrix. The presence of ZrB2 ceramic phase was confirmed by X-ray diffraction (XRD) analysis. Hardness of pure Zr was measured as 280 ± 12 HV and, by increasing the BN content in the feedstock, the hardness was found to increase. In Zr-5%BN composite, the hardness was 421 ± 10 HV and the same for Zr-10%BN composite was 562 ± 10 HV. It is envisioned that such multi-materials additive manufacturing will enable products in the future that cannot be manufactured using traditional approaches particularly in the areas of high-temperature metal-ceramic composites with compositional and functional gradation.

  4. Association of serum uric acid with high-sensitivity C-reactive protein in postmenopausal women.

    Science.gov (United States)

    Raeisi, A; Ostovar, A; Vahdat, K; Rezaei, P; Darabi, H; Moshtaghi, D; Nabipour, I

    2017-02-01

    To explore the independent correlation between serum uric acid and low-grade inflammation (measured by high-sensitivity C-reactive protein, hs-CRP) in postmenopausal women. A total of 378 healthy Iranian postmenopausal women were randomly selected in a population-based study. Circulating hs-CRP levels were measured by highly specific enzyme-linked immunosorbent assay method and an enzymatic calorimetric method was used to measure serum levels of uric acid. Pearson correlation coefficient, multiple linear regression and logistic regression models were used to analyze the association between uric acid and hs-CRP levels. A statistically significant correlation was seen between serum levels of uric acid and log-transformed circulating hs-CRP (r = 0.25, p uric acid levels (β = 0.20, p uric acid levels (odds ratio =1.52, 95% confidence interval 1.18-1.96). Higher serum uric acid levels were positively and independently associated with circulating hs-CRP in healthy postmenopausal women.

  5. Nanoporous Hybrid Electrolytes for High-Energy Batteries Based on Reactive Metal Anodes

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Zhengyuan [Department of Materials Science and Engineering, Cornell University, Ithaca NY 14850 USA; Zachman, Michael J. [School of Applied and Engineering Physics, Cornell University, Ithaca NY 14850 USA; Choudhury, Snehashis [School of Chemical Engineering and Biomolecular Engineering, Cornell University, Ithaca NY 14850 USA; Wei, Shuya [School of Chemical Engineering and Biomolecular Engineering, Cornell University, Ithaca NY 14850 USA; Ma, Lin [Department of Materials Science and Engineering, Cornell University, Ithaca NY 14850 USA; Yang, Yuan [Department of Chemistry and Geochemistry, Colorado School of Mines, Golden CO 80401 USA; Kourkoutis, Lena F. [School of Applied and Engineering Physics, Cornell University, Ithaca NY 14850 USA; Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca NY 14853 USA; Archer, Lynden A. [Department of Materials Science and Engineering, Cornell University, Ithaca NY 14850 USA; School of Chemical Engineering and Biomolecular Engineering, Cornell University, Ithaca NY 14850 USA

    2017-01-06

    Successful strategies for stabilizing electrodeposition of reactive metals, including lithium, sodium, and aluminum are a requirement for safe, high-energy electrochemical storage technologies that utilize these metals as anodes. Unstable deposition produces high-surface area dendritic structures at the anode/electrolyte interface, which causes premature cell failure by complex physical and chemical processes that have presented formidable barriers to progress. Here, it is reported that hybrid electrolytes created by infusing conventional liquid electrolytes into nanoporous membranes provide exceptional ability to stabilize Li. Electrochemical cells based on γ-Al2O3 ceramics with pore diameters below a cut-off value above 200 nm exhibit long-term stability even at a current density of 3 mA cm-2. The effect is not limited to ceramics; similar large enhancements in stability are observed for polypropylene membranes with less monodisperse pores below 450 nm. These findings are critically assessed using theories for ion rectification and electrodeposition reactions in porous solids and show that the source of stable electrodeposition in nanoporous electrolytes is fundamental.

  6. Growth of high quality AlN films on CVD diamond by RF reactive magnetron sputtering

    Science.gov (United States)

    Chen, Liang-xian; Liu, Hao; Liu, Sheng; Li, Cheng-ming; Wang, Yi-chao; An, Kang; Hua, Chen-yi; Liu, Jin-long; Wei, Jun-jun; Hei, Li-fu; Lv, Fan-xiu

    2018-02-01

    A highly oriented AlN layer has been successfully grown along the c-axis on a polycrystalline chemical vapor deposited (CVD) diamond by RF reactive magnetron sputtering. Structural, morphological and mechanical properties of the heterostructure were investigated by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), Transmission Electron Microscopy (TEM), X-ray diffraction (XRD), Nano-indentation and Four-probe meter. A compact AlN film was demonstrated on the diamond layer, showing columnar grains and a low surface roughness of 1.4 nm. TEM results revealed a sharp AlN/diamond interface, which was characterized by the presence of a distinct 10 nm thick buffer layer resulting from the initial AlN growth stage. The FWHM of AlN (002) diffraction peak and its rocking curve are as low as 0.41° and 3.35° respectively, indicating a highly preferred orientation along the c-axis. AlN sputtered films deposited on glass substrates show a higher bulk resistivity (up to 3 × 1012 Ω cm), compared to AlN films deposited on diamond (∼1010 Ω cm). Finally, the film hardness and Young's modulus of AlN films on diamond are 25.8 GPa and 489.5 GPa, respectively.

  7. Mineral Surface Rearrangement at High Temperatures: Implications for Extraterrestrial Mineral Grain Reactivity.

    Science.gov (United States)

    King, Helen E; Plümper, Oliver; Putnis, Christine V; O'Neill, Hugh St C; Klemme, Stephan; Putnis, Andrew

    2017-04-20

    Mineral surfaces play a critical role in the solar nebula as a catalytic surface for chemical reactions and potentially acted as a source of water during Earth's accretion by the adsorption of water molecules to the surface of interplanetary dust particles. However, nothing is known about how mineral surfaces respond to short-lived thermal fluctuations that are below the melting temperature of the mineral. Here we show that mineral surfaces react and rearrange within minutes to changes in their local environment despite being far below their melting temperature. Polished surfaces of the rock and planetary dust-forming silicate mineral olivine ((Mg,Fe) 2 SiO 4 ) show significant surface reorganization textures upon rapid heating resulting in surface features up to 40 nm in height observed after annealing at 1200 °C. Thus, high-temperature fluctuations should provide new and highly reactive sites for chemical reactions on nebula mineral particles. Our results also may help to explain discrepancies between short and long diffusion profiles in experiments where diffusion length scales are of the order of 100 nm or less.

  8. Reactive transport modelling of a high-pH infiltration test in concrete

    Science.gov (United States)

    Chaparro, M. Carme; Soler, Josep M.; Saaltink, Maarten W.; Mäder, Urs K.

    2017-06-01

    A laboratory-scale tracer test was carried out to characterize the transport properties of concrete from the Radioactive Waste Disposal Facility at El Cabril (Spain). A hyperalkaline solution (K-Ca-OH, pH = 13.2) was injected into a concrete sample under a high entry pressure in order to perform the experiment within a reasonable time span, obtaining a decrease of permeability by a factor of 1000. The concentrations of the tracers, major elements (Ca2+, SO4 2 - , K+ and Na+) and pH were measured at the outlet of the concrete sample. A reactive transport model was built based on a double porosity conceptual model, which considers diffusion between a mobile zone, where water can flow, and an immobile zone without any advective transport. The numerical model assumed that all reactions took place in the immobile zone. The cement paste consists of C-S-H gel, portlandite, ettringite, calcite and gypsum, together with residual alite and belite. Two different models were compared, one with portlandite in equilibrium (high initial surface area) and another one with portlandite reaction controlled by kinetics (low initial surface area). Overall the results show dissolution of alite, belite, gypsum, quartz, C-S-H gel and ettringite and precipitation of portlandite and calcite. Permeability could have decreased due to mineral precipitation.

  9. High density plasma reactive ion etching of Ru thin films using non-corrosive gas mixture

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Su Min; Garay, Adrian Adalberto; Lee, Wan In; Chung, Chee Won, E-mail: cwchung@inha.ac.kr

    2015-07-31

    Inductively coupled plasma reactive ion etching (ICPRIE) of Ru thin films patterned with TiN hard masks was investigated using a CH{sub 3}OH/Ar gas mixture. As the CH{sub 3}OH concentration in CH{sub 3}OH/Ar increased, the etch rates of Ru thin films and TiN hard masks decreased. However, the etch selectivity of Ru films on TiN hard masks increased and the etch slope of Ru film improved at 25% CH{sub 3}OH/Ar. With increasing ICP radiofrequency power and direct current bias voltage and decreasing process pressure, the etch rates of Ru films increased, and the etch profiles were enhanced without redeposition on the sidewall. Optical emission spectroscopy and X-ray photoelectron spectroscopy were employed to analyze the plasma and surface chemistry. Based on these results, Ru thin films were oxidized to RuO{sub 2} and RuO{sub 3} compounds that were removed by sputtering of ions and the etching of Ru thin films followed a physical sputtering with the assistance of chemical reaction. - Highlights: • Etching of Ru films in CH{sub 3}OH/Ar was investigated. • High selectivity and etch profile with high degree of anisotropy were obtained. • XPS analysis was examined to identify the etch chemistry. • During etching Ru was oxidized to RuO{sub 2} and RuO{sub 3} can be easily sputtered off.

  10. Pebble Fuel Handling and Reactivity Control for Salt-Cooled High Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Per [Univ. of California, Berkeley, CA (United States). Dept. of Nuclear Engineering; Greenspan, Ehud [Univ. of California, Berkeley, CA (United States). Dept. of Nuclear Engineering

    2015-02-09

    This report documents the work completed on the X-PREX facility under NEUP Project 11- 3172. This project seeks to demonstrate the viability of pebble fuel handling and reactivity control for fluoride salt-cooled high-temperature reactors (FHRs). The research results also improve the understanding of pebble motion in helium-cooled reactors, as well as the general, fundamental understanding of low-velocity granular flows. Successful use of pebble fuels in with salt coolants would bring major benefits for high-temperature reactor technology. Pebble fuels enable on-line refueling and operation with low excess reactivity, and thus simpler reactivity control and improved fuel utilization. If fixed fuel designs are used, the power density of salt- cooled reactors is limited to 10 MW/m3 to obtain adequate duration between refueling, but pebble fuels allow power densities in the range of 20 to 30 MW/m3. This can be compared to the typical modular helium reactor power density of 5 MW/m3. Pebble fuels also permit radial zoning in annular cores and use of thorium or graphite pebble blankets to reduce neutron fluences to outer radial reflectors and increase total power production. Combined with high power conversion efficiency, compact low-pressure primary and containment systems, and unique safety characteristics including very large thermal margins (>500°C) to fuel damage during transients and accidents, salt-cooled pebble fuel cores offer the potential to meet the major goals of the Advanced Reactor Concepts Development program to provide electricity at lower cost than light water reactors with improved safety and system performance.This report presents the facility description, experimental results, and supporting simulation methods of the new X-Ray Pebble Recirculation Experiment (X-PREX), which is now operational and being used to collect data on the behavior of slow dense granular flows relevant to pebble bed reactor core designs. The X

  11. Effects of attachment-based interventions on maternal sensitivity and infant attachment: differential susceptibility of highly reactive infants.

    Science.gov (United States)

    Velderman, Mariska Klein; Bakermans-Kranenburg, Marian J; Juffer, Femmie; van IJzendoorn, Marinus H

    2006-06-01

    The current intervention study aimed at breaking the potential intergenerational cycle of insecure attachment. The authors randomly assigned 81 first-time mothers to one of two intervention groups or a control group. The interventions involved four home visits when the infants were between 7 and 10 months old. The first intervention, VIPP, consisted of video-feedback and brochures to enhance sensitive parenting. The second intervention, VIPP-R, involved additional discussions of mothers' childhood attachment experiences in relation to their current caregiving. After the intervention, intervention mothers were more sensitive than control mothers. The interventions were most effective for highly reactive children and their mothers, providing experimental support for Belsky's (1997) hypothesis of highly reactive versus less reactive children's evolutionary based differential susceptibility to rearing influences. ((c) 2006 APA, all rights reserved).

  12. Bronchial reactivity in hyperresponsive patients and healthy individuals: demonstration with high resolution computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Schueller, G. E-mail: gerd.schueller@univie.ac.at; Neumann, K.; Helbich, T.; Riemer, H.; Backfrieder, W.; Sertl, K.; Herold, C.J

    2004-11-01

    Objective: High resolution computed tomography (HRCT) was used to assess the extent of bronchial reactivity after inhalative bronchoprovocation and dilation in hyperresponsive patients and healthy subjects. Patients and methods: Patients with mild intermittent asthma, 15 with a >20% decrease in FEV{sub 1} and a >10 mmHg (PC{sub 20}+) in PaO{sub 2}, 12 with a <20% decrease in FEV{sub 1} and a >10 mmHg (PC{sub 20}-) in PaO{sub 2} after provocation, and eight healthy humans were included in the study. Changes in cross-sectional area in a total of 1256 bronchi and in bronchial wall area (792 bronchi) were evaluated after histamine-triggered bronchoprovocation and salbutamol-induced bronchodilation at high lung volumes (FVC 80%). Data were compared with the results of pulmonary function tests (FEV{sub 1}, PaO{sub 2}, PaCO{sub 2}). Results: In all groups, a significant decrease in bronchial cross-sectional area (P<0.001) and a significant increase in bronchial wall area (P<0.001) were observed subsequent to bronchoprovocation. After bronchodilation, the increase in cross-sectional area (P<0.001) and the further increase in airway wall area (P<0.01) were significant in all groups. In PC{sub 20}+ and PC{sub 20}- asthmatics, significant differences (P<0.05) in PaO{sub 2}, >10 mmHg between baseline and provocation were observed. In healthy persons, the PaO{sub 2} decrease was <10 mmHg (P>0.05). After histamine provocation, the decrease in FEV{sub 1} was measured in the PC{sub 20}+ group, whereas a <20% FEV{sub 1} decrease was found in the PC{sub 20}- and the control groups, respectively. No significant correlations were observed between radiological data and the results of pulmonary function tests. Conclusions: HRCT demonstrated bronchial reactivity in hyperresponsive patients and, unexpectedly, in healthy subjects. The applied pulmonary function tests failed to characterize bronchial reactions in the healthy subjects. Based on these results, HRCT is a useful tool by which

  13. Alpha reactivity to first names differs in subjects with high and low dream recall frequency

    Directory of Open Access Journals (Sweden)

    Perrine Marie RUBY

    2013-08-01

    Full Text Available Studies in cognitive psychology showed that personality (openness to experience, thin boundaries, absorption, creativity, nocturnal awakenings, and attitude toward dreams are significantly related to dream recall frequency (DRF. These results suggest the possibility of neurophysiological trait differences between subjects with high and low DRF. To test this hypothesis we compared sleep characteristics and alpha reactivity to sounds in subjects with high and low DRF using polysomnographic recordings and electroencephalography (EEG. We acquired EEG from 21 channels in 36 healthy subjects while they were presented with a passive auditory oddball paradigm (frequent standard tones, rare deviant tones and very rare first names during wakefulness and sleep (intensity, 50 dB above the subject’s hearing level. Subjects were selected as High-recallers (HR, DRF = 4.4 ± 1.1 dream recalls per week and Low-recallers (LR, DRF = 0.25 ± 0.1 using a questionnaire and an interview on sleep and dream habits. Despite the disturbing setup, the subjects’ quality of sleep was generally preserved. First names induced a more sustained decrease in alpha activity in HR than in LR at Pz (1000-1200ms during wakefulness, but no group difference was found in REM sleep. The current dominant hypothesis proposes that alpha rhythms would be involved in the active inhibition of the brain regions not involved in the ongoing brain operation. According to this hypothesis, a more sustained alpha decrease in HR would reflect a longer release of inhibition, suggesting a deeper processing of complex sounds than in LR during wakefulness. A possibility to explain the absence of group difference during sleep is that increase in alpha power in HR may have resulted in awakenings. Our results support this hypothesis since HR experienced more intra sleep wakefulness than LR (30 ± 4 vs 14 ± 4 min. As a whole our results support the hypothesis of neurophysiological trait differences in

  14. About a fuel for burnup reactor of periodical pulsed nuclear pumped laser

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, A.I.; Lukin, A.V.; Magda, L.E.; Magda, E.P.; Pogrebov, I.S.; Putnikov, I.S.; Khmelnitsky, D.V.; Scherbakov, A.P. [Russian Federal Nuclear Center, Snezhinsk (Russian Federation)

    1998-07-01

    A physical scheme of burnup reactor for a Periodic Pulsed Nuclear Pumped Laser was supposed. Calculations of its neutron physical parameters were made. The general layout and construction of basic elements of the reactor are discussed. The requirements for the fuel and fuel elements are established. (author)

  15. Radiochemical Assays of Irradiated VVER-440 Fuel for Use in Spent Fuel Burnup Credit Activities

    Energy Technology Data Exchange (ETDEWEB)

    Jardine, L J

    2005-04-25

    The objective of this spent fuel burnup credit work was to study and describe a VVER-440 reactor spent fuel assembly (FA) initial state before irradiation, its operational irradiation history and the resulting radionuclide distribution in the fuel assembly after irradiation. This work includes the following stages: (1) to pick out and select a specific spent (irradiated) FA for examination; (2) to describe the FA initial state before irradiation; (3) to describe the irradiation history, including thermal calculations; (4) to examine the burnup distribution of select radionuclides along the FA height and cross-section; (5) to examine the radionuclide distributions; (6) to determine the Kr-85 release into the plenum; (7) to select and prepare FA rod specimens for destructive examinations; (8) to determine the radionuclide compositions, isotope masses and burnup in the rod specimens; and (9) to analyze, document and process the results. The specific workscope included the destructive assay (DA) of spent fuel assembly rod segments with an {approx}38.5 MWd/KgU burnup from a single VVER-440 fuel assembly from the Novovorenezh reactor in Russia. Based on irradiation history criteria, four rods from the fuel assembly were selected and removed from the assembly for examination. Next, 8 sections were cut from the four rods and sent for destructive analysis of radionuclides by radiochemical analyses. The results were documented in a series of seven reports over a period of {approx}1 1/2 years.

  16. High sensitivity C-reactive protein in airline pilots with metabolic syndrome.

    Science.gov (United States)

    Alonso-Rodríguez, César; Medina-Font, Juan

    2012-05-01

    Airline pilots belong to a relatively high-income, healthy population, with sedentary behavior during their flight activity, who often eat unsuitable meals. We assessed the prevalence of metabolic syndrome (MS) and the levels of high sensitivity C-reactive protein (hs-CRP) in a population of airline pilot in order to study a possible relationship between the hs-CRP and MS. MS was established according to the National Cholesterol Education Program, Adult Treatment Panel III. hs-CRP was classified into three categories: Low 3 mg x L(-1). The prevalence of MS was 14.8%. The hs-CRP level in the population studied was 1.68 +/- 1.79 mg x L(-1). hs-CRP significantly increased with age. The pilots with MS presented significantly higher hs-CRP levels (median = 1.9 with an interquartile range (IQR) = 2.5 mg x L(-1)) than the pilots without MS (median = 0.9 and IQR = 1.275 mg x L(-1)). MS significantly increased in the groups with high hs-CRP in comparison with pilots with intermediate hs-CRP levels and with those with low hs-CRP levels. A similar association was found between the levels of hs-CRP and the prevalence of MS in the three age groups. The levels of hs-CRP increased in pilots as they presented greater numbers of MS diagnostic criteria. hs-CRP rises significantly in pilots of increasing age, in pilots with MS as compared to those without the syndrome, and in pilots as they present greater numbers of MS diagnostic criteria. The prevalence of MS increased among the groups with higher levels of hs-CRP.

  17. Association between high sensitivity C-reactive protein and dietary intake in Vietnamese young women

    Science.gov (United States)

    Ko, Ahra; Kim, Hyesook; Han, Chan-Jung; Kim, Ji-Myung; Chung, Hye-Won

    2014-01-01

    BACKGROUND/OBJECTIVES High sensitivity C-reactive protein (hsCRP) is a strong independent predictor of future cardiovascular disease (CVD) risk. We evaluated the relationship between hsCRP and dietary intake in apparently healthy young women living in southern Vietnam. SUBJECTS/METHODS Serum hsCRP was measured and dietary intake data were obtained using the 1-day 24-hour recall method in women (n = 956; mean age, 25.0 ± 5.7 years) who participated in the International Collaboration Study for the Construction of Asian Cohort of the Korean Genome and Epidemiology Study (KoGES) in 2011. RESULTS Women in the high risk group (> 3 mg/L) consumed fewer fruits and vegetables, total plant food, potassium, and folate than those in the low risk group (< 1 mg/L). A multiple regression analysis after adjusting for covariates revealed a significant negative association between hsCRP and fruit and vegetable consumption. A logistic regression analysis showed that the odds ratio (OR) of having a high hsCRP level in women with the highest quartiles of consumption of fruits and vegetables [OR, 0.391; 95% confidence interval (CI), 0.190-0.807], potassium [OR, 0.425; 95% CI, 0.192-0.939] and folate [OR, 0.490; 95% CI, 0.249-0.964] were significantly lower than those in the lowest quartiles. CONCLUSIONS These results suggest that, in young Vietnamese women, an increased consumption of fruit and vegetables might be beneficial for serum hsCRP, a risk factor for future CVD events. PMID:25110566

  18. Anthropogenic Emissions of Highly Reactive Volatile Organic Compounds (HRVOCs) Inferred from Oversampling of OMI HCHO Columns

    Science.gov (United States)

    Zhu, Lei; Jacob, Daniel; Mickley, Loretta; Marais, Eloise; Zhang, Aoxing; Cohan, Daniel; Yoshida, Yasuko; Duncan, Bryan; Abad, Gonzalo Gonzalez; Chance, Kelly; hide

    2014-01-01

    Satellite observations of formaldehyde (HCHO) columns provide top-down constraints on emissions of highly reactive volatile organic compounds (HRVOCs). This approach has been used previously to constrain emissions of isoprene from vegetation, but application to US anthropogenic emissions has been stymied by lack of a discernable HCHO signal. Here we show that oversampling of HCHO data from the Ozone Monitoring Instrument (OMI) for 2005 - 2008 enables quantitative detection of urban and industrial plumes in eastern Texas including Houston, Port Arthur, and Dallas-Fort Worth. By spatially integrating the individual urban-industrial HCHO plumes observed by OMI we can constrain the corresponding HCHO-weighted HRVOC emissions. Application to the Houston plume indicates a HCHO source of 260 plus or minus 110 kmol h-1 and implies a factor of 5.5 plus or minus 2.4 underestimate of anthropogenic HRVOC emissions in the US Environmental Protection Agency inventory. With this approach we are able to monitor the trend in HRVOC emissions over the US, in particular from the oil-gas industry, over the past decade.

  19. Chemical instability of graphene oxide following exposure to highly reactive radicals in advanced oxidation processes.

    Science.gov (United States)

    Wang, Zhaohui; Sun, Linyan; Lou, Xiaoyi; Yang, Fei; Feng, Min; Liu, Jianshe

    2017-12-01

    The rapidly increasing and widespread use of graphene oxide (GO) as catalyst supports, requires further understanding of its chemical stability in advanced oxidation processes (AOPs). In this study, UV/H2O2 and UV/persulfate (UV/PS) processes were selected to test the chemical instability of GO in terms of their performance in producing highly reactive hydroxyl radicals (OH) and sulfate radicals (SO4(-)), respectively. The degradation intermediates were characterized using UV-visible absorption spectra (UV-vis), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), Raman spectroscopy, and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Experimental data indicate that UV/PS process was more effective in enhancing GO degradation than the UV/H2O2 system. The overall oxygen-containing functionalities (e.g. CO, CO and OCO groups) dramatically declined. After radical attack, sheet-like GO was destructed into lots of flakes and some low-molecular-weight molecules were detected. The results suggest GO is most vulnerable against SO4(-) radical attack, which deserves special attention while GO acts as a catalyst support or even as a catalyst itself. Therefore, stability of GO and its derivatives should be carefully assessed before they are applied to SO4(-)-based AOPs. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Synthesis and characterization of high wash fastness novel azo reactive dyes incorporating aromatic bridged diamines

    Directory of Open Access Journals (Sweden)

    Aamer Saeed

    2018-01-01

    Full Text Available A new series of azo reactive dyes containing free chlorine atoms have been synthesized. The synthetic methodology involves the diazotization of 4′4-diamino diphenylamine-2-sulfonic acid (2 followed by azo coupling with 1-amino-8-naphthol-3,6-disulfonic acid (3 in alkaline medium to yield intermediate dye (4. Condensation of the latter with 1,3,5-trichlorotriazine afforded the cyanurated dye (5. A number of novel bis aromatic diamines (1a–j were separately synthesized as bridging groups and were coupled with cyanurated dye (5 at room temperature to provide the target dyes designated as S1–S10 containing triazine and linker in a single molecule. The structures of newly synthesized compounds were confirmed by analytical data and spectroscopic techniques. The synthesized dyes were applied on cotton fibers to assess their light fastness, wash fastness and rubbing fastness and were found to possess medium to high fastness values in different dyes.

  1. High-sensitive C-Reactive Protein as a Marker for Inflammation in Irritable Bowel Syndrome.

    Science.gov (United States)

    Hod, Keren; Ringel-Kulka, Tamar; Martin, Christopher F; Maharshak, Nitsan; Ringel, Yehuda

    2016-03-01

    Recent studies demonstrated low-grade inflammation in patients with irritable bowel syndrome (IBS). However, these studies have been relatively small and do not enable examination of this factor in different subtypes of IBS and the possibility of confounding effects of comorbidities that may be associated with inflammatory responses. To investigate the association between high-sensitive C-reactive protein (hs-CRP) and the diagnosis of IBS, IBS subtypes, symptoms' severity, and IBS-associated comorbidities. This cross-sectional study uses data from a large matched case-control study of IBS subjects and healthy controls (HC). hs-CRP levels were measured in all subjects. IBS diagnosis was determined by Rome III criteria, negative screening blood tests, and normal colonoscopy. Subjects were evaluated for IBS severity and associated pain and psychological comorbidities. A total of 242 IBS patients and 244 HC were studied. Median hs-CRP levels in the IBS group were significantly higher than in HC (1.80; interquartile range, 0.7 to 4.04 mg/L vs. 1.20, interquartile range, 0.5 to 2.97 mg/L respectively, Pinflammation in the pathogenesis and/or clinical presentation of IBS.

  2. Maintaining the structure of templated porous materials for reactive and high-temperature applications.

    Science.gov (United States)

    Rudisill, Stephen G; Wang, Zhiyong; Stein, Andreas

    2012-05-15

    Nanoporous and nanostructured materials are becoming increasingly important for advanced applications involving, for example, bioactive materials, catalytic materials, energy storage and conversion materials, photonic crystals, membranes, and more. As such, they are exposed to a variety of harsh environments and often experience detrimental morphological changes as a result. This article highlights material limitations and recent advances in porous materials--three-dimensionally ordered macroporous (3DOM) materials in particular--under reactive or high-temperature conditions. Examples include systems where morphological changes are desired and systems that require an increased retention of structure, surface area, and overall material integrity during synthesis and processing. Structural modifications, changes in composition, and alternate synthesis routes are explored and discussed. Improvements in thermal or structural stability have been achieved by the isolation of nanoparticles in porous structures through spatial separation, by confinement in a more thermally stable host, by the application of a protective surface or an adhesive interlayer, by alloy or solid solution formation, and by doping to induce solute drag.

  3. Sleep disturbances in highly stress reactive mice: Modeling endophenotypes of major depression

    Directory of Open Access Journals (Sweden)

    Landgraf Rainer

    2011-03-01

    Full Text Available Abstract Background Neuronal mechanisms underlying affective disorders such as major depression (MD are still poorly understood. By selectively breeding mice for high (HR, intermediate (IR, or low (LR reactivity of the hypothalamic-pituitary-adrenocortical (HPA axis, we recently established a new genetic animal model of extremes in stress reactivity (SR. Studies characterizing this SR mouse model on the behavioral, endocrine, and neurobiological levels revealed several similarities with key endophenotypes observed in MD patients. HR mice were shown to have changes in rhythmicity and sleep measures such as rapid eye movement sleep (REMS and non-REM sleep (NREMS as well as in slow wave activity, indicative of reduced sleep efficacy and increased REMS. In the present study we were interested in how far a detailed spectral analysis of several electroencephalogram (EEG parameters, including relevant frequency bands, could reveal further alterations of sleep architecture in this animal model. Eight adult males of each of the three breeding lines were equipped with epidural EEG and intramuscular electromyogram (EMG electrodes. After recovery, EEG and EMG recordings were performed for two days. Results Differences in the amount of REMS and wakefulness and in the number of transitions between vigilance states were found in HR mice, when compared with IR and LR animals. Increased frequencies of transitions from NREMS to REMS and from REMS to wakefulness in HR animals were robust across the light-dark cycle. Detailed statistical analyses of spectral EEG parameters showed that especially during NREMS the power of the theta (6-9 Hz, alpha (10-15 Hz and eta (16-22.75 Hz bands was significantly different between the three breeding lines. Well defined distributions of significant power differences could be assigned to different times during the light and the dark phase. Especially during NREMS, group differences were robust and could be continuously monitored

  4. Generation of a high-valent iron imido corrolazine complex and NR group transfer reactivity.

    Science.gov (United States)

    Leeladee, Pannee; Jameson, Guy N L; Siegler, Maxime A; Kumar, Devesh; de Visser, Sam P; Goldberg, David P

    2013-04-15

    The generation of a new high-valent iron terminal imido complex prepared with a corrolazine macrocycle is reported. The reaction of [Fe(III)(TBP8Cz)] (TBP8Cz = octakis(4-tert-butylphenyl)corrolazinato) with the commercially available chloramine-T (Na(+)TsNCl(-)) leads to oxidative N-tosyl transfer to afford [Fe(IV)(TBP8Cz(+•))(NTs)] in dichloromethane/acetonitrile at room temperature. This complex was characterized by UV-vis, Mössbauer (δ = -0.05 mm s(-1), ΔE(Q) = 2.94 mm s(-1)), and EPR (X-band (15 K), g = 2.10, 2.00) spectroscopies, and together with reactivity patterns and DFT calculations has been established as an iron(IV) species antiferromagnetically coupled with a Cz-π-cation-radical (S(total) = 1/2 ground state). Reactivity studies with triphenylphosphine as substrate show that [Fe(IV)(TBP8Cz(+•))(NTs)] is an efficient NTs transfer agent, affording the phospharane product Ph3P═NTs under both stoichiometric and catalytic conditions. Kinetic analysis of this reaction supports a bimolecular NTs transfer mechanism with rate constant of 70(15) M(-1) s(-1). These data indicate that [Fe(IV)(TBP8Cz(+•))(NTs)] reacts about 100 times faster than analogous Mn terminal arylimido corrole analogues. It was found that two products crystallize from the same reaction mixture of Fe(III)(TBP8Cz) + chloramine-T + PPh3, [Fe(IV)(TBP8Cz)(NPPh3)] and [Fe(III)(TBP8Cz)(OPPh3)], which were definitively characterized by X-ray crystallography. The sequential production of Ph3P═NTs, Ph3P═NH, and Ph3P═O was observed by (31)P NMR spectroscopy and led to a proposed mechanism that accounts for all of the observed products. The latter Fe(III) complex was then rationally synthesized and structurally characterized from Fe(III)(TBP8Cz) and OPPh3, providing an important benchmark compound for spectroscopic studies. A combination of Mössbauer and EPR spectroscopies led to the characterization of both intermediate spin (S = 3/2 and low spin (S = 1/2) Fe(III) corrolazines, as

  5. Application of Genetic Algorithm methodologies in fuel bundle burnup optimization of Pressurized Heavy Water Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jayalal, M.L., E-mail: jayalal@igcar.gov.in [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Ramachandran, Suja [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Rathakrishnan, S. [Reactor Physics Section, Madras Atomic Power Station (MAPS), Kalpakkam, Tamil Nadu (India); Satya Murty, S.A.V. [Electronics, Instrumentation and Radiological Safety Group (EIRSG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India); Sai Baba, M. [Resources Management Group (RMG), Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamil Nadu (India)

    2015-01-15

    Highlights: • We study and compare Genetic Algorithms (GA) in the fuel bundle burnup optimization of an Indian Pressurized Heavy Water Reactor (PHWR) of 220 MWe. • Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are considered. • For the selected problem, Multi Objective GA performs better than Penalty Functions based GA. • In the present study, Multi Objective GA outperforms Penalty Functions based GA in convergence speed and better diversity in solutions. - Abstract: The work carried out as a part of application and comparison of GA techniques in nuclear reactor environment is presented in the study. The nuclear fuel management optimization problem selected for the study aims at arriving appropriate reference discharge burnup values for the two burnup zones of 220 MWe Pressurized Heavy Water Reactor (PHWR) core. Two Genetic Algorithm methodologies namely, Penalty Functions based GA and Multi Objective GA are applied in this study. The study reveals, for the selected problem of PHWR fuel bundle burnup optimization, Multi Objective GA is more suitable than Penalty Functions based GA in the two aspects considered: by way of producing diverse feasible solutions and the convergence speed being better, i.e. it is capable of generating more number of feasible solutions, from earlier generations. It is observed that for the selected problem, the Multi Objective GA is 25.0% faster than Penalty Functions based GA with respect to CPU time, for generating 80% of the population with feasible solutions. When average computational time of fixed generations are considered, Penalty Functions based GA is 44.5% faster than Multi Objective GA. In the overall performance, the convergence speed of Multi Objective GA surpasses the computational time advantage of Penalty Functions based GA. The ability of Multi Objective GA in producing more diverse feasible solutions is a desired feature of the problem selected, that helps the

  6. Evidence for greater cue reactivity among low-dependent vs. high-dependent smokers.

    Science.gov (United States)

    Watson, Noreen L; Carpenter, Matthew J; Saladin, Michael E; Gray, Kevin M; Upadhyaya, Himanshu P

    2010-07-01

    Cue reactivity paradigms are well-established laboratory procedures used to examine subjective craving in response to substance-related cues. For smokers, the relationship between nicotine dependence and cue reactivity has not been clearly established. The main aim of the present study was to further examine this relationship. Participants (N=90) were between the ages 18-40 and smoked > or =10 cigarettes per day. Average nicotine dependence (Fagerström Test for Nicotine Dependence; FTND) at baseline was 4.9 (SD=2.1). Participants completed four cue reactivity sessions consisting of two in vivo cues (smoking and neutral) and two affective imagery cues (stressful and relaxed), all counterbalanced. Craving in response to cues was assessed following each cue exposure using the Questionnaire of Smoking Urges-Brief (QSU-B). Differential cue reactivity was operationally defined as the difference in QSU scores between the smoking and neutral cues, and between the stressful and relaxed cues. Nicotine dependence was significantly and negatively associated with differential cue reactivity scores in regard to hedonic craving (QSU factor 1) for both in vivo and imagery cues, such that those who had low FTND scores demonstrated greater differential cue reactivity than those with higher FTND scores (beta=-.082; p=.037; beta=-.101; p=.023, respectively). Similar trends were found for the Total QSU and for negative reinforcement craving (QSU factor 2), but did not reach statistical significance. Under partially sated conditions, less dependent smokers may be more differentially cue reactive to smoking cues as compared to heavily dependent smokers. These findings offer methodological and interpretative implications for cue reactivity studies. 2010 Elsevier Ltd. All rights reserved.

  7. Evidence for greater cue reactivity among low dependent vs. high dependent smokers

    Science.gov (United States)

    Watson, Noreen L.; Carpenter, Matthew J.; Saladin, Michael E.; Gray, Kevin M.; Upadhyaya, Himanshu P.

    2010-01-01

    Introduction Cue reactivity paradigms are well-established laboratory procedures used to examine subjective craving in response to substance-related cues. For smokers, the relationship between nicotine dependence and cue reactivity has not been clearly established. The main aim of the present study was to further examine this relationship. Methods Participants (N=90) were between the ages 18–40 and smoked ≥10 cigarettes per day. Average nicotine dependence (Fagerström Test for Nicotine Dependence; FTND) at baseline was 4.9 (SD=2.1). Participants completed four cue reactivity sessions consisting of two in vivo cues (smoking, neutral) and two affective imagery cues (stressful, relaxed), all counterbalanced. Craving in response to cues was assessed following each cue exposure using the Questionnaire of Smoking Urges—Brief (QSU-B). Differential cue reactivity was operationally defined as the difference in QSU scores between the smoking and neutral cues, and between the stressful and relaxed cues. Results Nicotine dependence was significantly and negatively associated with differential cue reactivity scores in regards to hedonic craving (QSU factor 1) for both in vivo and imagery cues, such that those who had low FTND scores demonstrated greater differential cue reactivity than those with higher FTND scores (β = −.082; p = .037; β = −.101; p = .023, respectively). Similar trends were found for the total QSU and for negative reinforcement craving (QSU factor 2), but did not reach statistical significance. Discussion Under partially sated conditions, less dependent smokers may be more differentially cue reactive to smoking cues as compared to heavily dependent smokers. These findings offer methodological and interpretative implications for cue reactivity studies. PMID:20206451

  8. High Risk of Hepatitis B Reactivation among Patients with Acute Myeloid Leukemia.

    Directory of Open Access Journals (Sweden)

    Chien-Yuan Chen

    Full Text Available Hepatitis B virus (HBV infections are common and associated with significant morbidity and mortality in cancer patients. However, the incidence and risk factors of HBV reactivation in patients with acute myeloid leukemia (AML are rarely investigated.AML patients followed-up at the National Taiwan University Hospital between 2006 and 2012 were analyzed. The clinical characteristics and laboratory data were retrospectively reviewed.Four hundred and ninety patients comprising 265 men and 225 women were studied. The median age was 52 years (range, 18 - 94. Chronic HBV carriage was documented at the time of leukemia diagnosis in 57 (11.6% patients. Forty-six (80.7% of the 57 HBV carriers received prophylaxis with anti-HBV agents. Sixteen HBV carriers (28.1% developed hepatitis B reactivation during or after chemotherapy, including 7 patients who had discontinued antiviral therapy. The incidence of hepatitis B reactivation among AML patients with HBV carriage was 9.5 per 100 person-years. Prophylaxis with anti-HBV agents significantly decreased the risk of hepatitis B reactivation among HBV carriers (13% vs. 61%, p<0.001. Four (2.8% of 142 patients with initial positive anti-HBsAb and anti-HBcAb experienced hepatitis B reactivation and lost their protective anti-HBsAb. Multivariate analysis revealed that diabetes mellitus (p=0.008, odds ratio (OR = 2.841, 95% confident interval (CI: 0.985-8.193 and carriage of HBsAg (p<0.001, OR=36.878, 95% CI: 11.770-115.547 were independent risk factors for hepatitis B reactivation in AML patients.Hepatitis B reactivation is not uncommon in the HBsAg positive AML patients. Prophylaxis with anti-HBV agent significantly decreased the risk of hepatitis B reactivation.

  9. Amygdala reactivity to emotional faces at high and low intensity in generalized social phobia: A 4T functional MRI study

    NARCIS (Netherlands)

    Yoon, K.L.; Fitzgerald, D.A.; Angstadt, M.; McCarron, R.A.; Phan, K.L.

    2007-01-01

    Using functional magnetic resonance imaging, we measured amygdala reactivity to faces varying on emotional intensity in subjects with generalized social phobia (GSP) and matched healthy controls, and observed greater bilateral activation to high (vs. low) intensity expressions in the phobic group,

  10. Regulatory Behaviors and Stress Reactivity among Infants at High Risk for Fetal Alcohol Spectrum Disorders: An Exploratory Study

    Science.gov (United States)

    Jirikowic, Tracy; Chen, Maida; Nash, Jennifer; Gendler, Beth; Olson, Heather Carmichael

    2016-01-01

    Introduction: This article examines regulatory behaviors and physiological stress reactivity among 6-15 month-old infants with moderate to heavy prenatal alcohol exposure (PAE), a group at very high risk for fetal alcohol spectrum disorders and self-regulation impairments, compared to low risk infants with no/low exposure. Participants: Eighteen…

  11. Effects of Biomass Feedstock on the Yield and Reactivity of Soot from Fast Pyrolysis at High Temperatures

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Jensen, Peter A.; Glarborg, Peter

    This study investigated the effect of feedstock on the yield, nanostructure and reactivity of soot. Woody and herbaceous biomass were pyrolyzed at high heating rates and temperatures of 1250 and 1400°C in a drop tube furnace. The collected solid residues were structurally characterized by electron...

  12. Mechanisms of wetting and brazing of silicon carbide by Cu-Si non reactive alloys for high temperature applications

    Energy Technology Data Exchange (ETDEWEB)

    Gasse, A.; Chaumat, G. [Association Euratom-CEA, Centre d`Etudes Nucleaires de Cadarache, 13 - Saint-Paul-lez-Durance (France). Dept. de Recherches sur la Fusion Controlee; Rado, C.; Eustathopoulos, N. [Institut National Polytechnique, 38 - Grenoble (France)

    1995-12-31

    Sessile drop experiments were carried out with a non reactive Cu 24 at % Si alloy on {alpha}-SiC single crystals and polycrystalline substrates under high vacuum or a commercial argon atmosphere. Experiments led to contact angles as low as 30 deg. and to a non reactive and strong interface. Wetting kinetics observed in this system has been identified to depend greatly on temperature and atmosphere. Brazing experiments were then performed using informations from sessile drop experiments. Influence of the brazing configuration is discussed. (author) 11 refs.

  13. Cardiovascular Reactivity in Patients With Major Depressive Disorder With High- or Low-Level Depressive Symptoms: A Cross-Sectional Comparison of Cardiovascular Reactivity to Laboratory-Induced Mental Stress.

    Science.gov (United States)

    Wang, Mei-Yeh; Chiu, Chen-Huan; Lee, Hsin-Chien; Su, Chien-Tien; Tsai, Pei-Shan

    2016-03-01

    Depression increases the risk of adverse cardiac events. Cardiovascular reactivity is defined as the pattern of cardiovascular responses to mental stress. An altered pattern of cardiovascular reactivity is an indicator of subsequent cardiovascular disease. Because depression and adverse cardiac events may have a dose-dependent association, this study examined the differences in cardiovascular reactivity to mental stress between patients with major depressive disorder (MDD) with high depression levels and those with low depression levels. Moreover, autonomic nervous system regulation is a highly plausible biological mechanism for the pattern of cardiovascular reactivity to mental stress. The association between cardiovascular reactivity and parameters of heart rate variability (HRV), an index for quantifying autonomic nervous system activity modulation, was thus examined. This study included 88 patients with MDD. HRV was measured before stress induction. The Stroop Color and Word Test and mirror star-tracing task were used to induce mental stress. We observed no significant association between depressive symptom level and any of the cardiovascular reactivity parameters. Cardiovascular reactivity to mental stress was comparable between patients with MDD with high-level depressive symptoms and those with low-level depressive symptoms. After adjusting for confounding variables, the high-frequency domain of HRV was found to be an independent predictor of the magnitude of heart rate reactivity (β = -.33, p = .002). In conclusion, the magnitude of cardiovascular reactivity may be independent of depression severity in patients with MDD. The autonomic regulation of cardiovascular responses to mental stress primarily influences heart rate reactivity in patients with MDD. © The Author(s) 2015.

  14. Soot structure and reactivity analysis by Raman microspectroscopy, temperature-programmed oxidation, and high-resolution transmission electron microscopy.

    Science.gov (United States)

    Knauer, Markus; Schuster, Manfred E; Su, Dangsheng; Schlögl, Robert; Niessner, Reinhard; Ivleva, Natalia P

    2009-12-17

    Raman microspectroscopy (RM), temperature-programmed oxidation (TPO), high-resolution transmission electron microscopy (HRTEM), and electron energy loss spectroscopy (EELS) were combined to get comprehensive information on the relationship between structure and reactivity of soot in samples of spark discharge (GfG), heavy duty engine diesel (EURO VI and IV) soot, and graphite powder upon oxidation by oxygen at increasing temperatures. GfG soot and graphite powder represent the higher and lower reactivity limits. Raman microspectroscopic analysis was conducted by determination of spectral parameters using a five band fitting procedure (G, D1-D4) as well as by evaluation of the dispersive character of the D mode. The analysis of spectral parameters shows a higher degree of disorder and a higher amount of molecular carbon for untreated GfG soot samples than for samples of untreated EURO VI and EURO IV soot. The structural analysis based on the dispersive character of the D mode revealed substantial differences in ordering descending from graphite powder, EURO IV, VI to GfG soot. HRTEM images and EELS analysis of EURO IV and VI samples indicated a different morphology and a higher structural order as compared to GfG soot in full agreement with the Raman analysis. These findings are also confirmed by the reactivity of soot during oxidation (TPO), where GfG soot was found to be the most reactive and EURO IV and VI soot samples exhibited a moderate reactivity.

  15. High fluence low-power laser irradiation induces mitochondrial permeability transition mediated by reactive oxygen species.

    Science.gov (United States)

    Wu, Shengnan; Xing, Da; Gao, Xuejuan; Chen, Wei R

    2009-03-01

    High fluence low-power laser irradiation (HF-LPLI) can induce cell apoptosis via the mitochondria/caspase-3 pathway. Here, we further investigated the mechanism involved in the apoptotic process in human lung adenocarcinoma cells (ASTC-a-1) at a laser irradiation fluence of 120 J/cm(2) (633 nm). Cytochrome c release was ascribed to mitochondrial permeability transition (MPT) because the release was prevented by cyclosporine (CsA), a specific inhibitor of MPT. Furthermore, mitochondrial permeability for calcein (approximately 620 Da) was another evidence for the MPT induction under HF-LPLI treatment. A high-level intracellular reactive oxygen species (ROS) generation was observed after irradiation. The photodynamically produced ROS caused onset of MPT, as the ROS scavenger docosahexaenoic acid (DHA) prevented the MPT. However, CsA failed to prevented cell death induced by HF-LPLI, indicating the existence of other signaling pathways. Following laser irradiation, Bax activation occurred after mitochondrial depolarization and cytochrome c release, indicating Bax activation was a downstream event. In the presence of CsA, Bax was still activated at the end-stage of apoptotic process caused by HF-LPLI, suggesting that Bax was involved in an alternative-signaling pathway, which was independent of MPT. Under HF-LPLI treatment, cell viabilities due to pre-treatment with DHA, CsA, or Bax small interfering RNA (siRNA) demonstrated that the MPT signaling pathway was dominant, while Bax signaling pathway was secondary, and more importantly ROS mediated both pathways. Taken together, these results showed that HF-LPLI induced cell apoptosis via the CsA-sensitive MPT, which was ROS-dependent. Furthermore, there existed a secondary signaling pathway through Bax activation. The observed link between MPT and triggering ROS could be a fundamental phenomenon in HF-LPLI-induced cell apoptosis.

  16. Synthesis of Self-Assembled Multifunctional Nanocomposite Catalysts with Highly Stabilized Reactivity and Magnetic Recyclability

    Science.gov (United States)

    Yu, Xu; Cheng, Gong; Zheng, Si-Yang

    2016-05-01

    In this paper, a multifunctional Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite catalyst with highly stabilized reactivity and magnetic recyclability was synthesized by a self-assembled method. The magnetic Fe3O4 nanoparticles were coated with a thin layer of the SiO2 to obtain a negatively charged surface. Then positively charged poly(ethyleneimine) polymer (PEI) was self-assembled onto the Fe3O4@SiO2 by electrostatic interaction. Next, negatively charged glutathione capped gold nanoparticles (GSH-AuNPs) were electrostatically self-assembled onto the Fe3O4@SiO2@PEI. After that, silver was grown on the surface of the nanocomposite due to the reduction of the dopamine in the alkaline solution. An about 5 nm thick layer of polydopamine (PDA) was observed to form the Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite was carefully characterized by the SEM, TEM, FT-IR, XRD and so on. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite shows a high saturation magnetization (Ms) of 48.9 emu/g, which allows it to be attracted rapidly to a magnet. The Fe3O4@SiO2@PEI-Au/Ag@PDA nanocomposite was used to catalyze the reduction of p-nitrophenol (4-NP) to p-aminophenol (4-AP) as a model system. The reaction kinetic constant k was measured to be about 0.56 min-1 (R2 = 0.974). Furthermore, the as-prepared catalyst can be easily recovered and reused for 8 times, which didn’t show much decrease of the catalytic capability.

  17. Does high reactive nitrogen input from the atmosphere decrease the carbon sink strength of a peatland?

    Science.gov (United States)

    Brümmer, Christian; Zöll, Undine; Hurkuck, Miriam; Schrader, Frederik; Kutsch, Werner

    2017-04-01

    Mid-latitude peatlands are often exposed to high atmospheric nitrogen deposition when located in close vicinity to agricultural land. As the impacts of altered deposition rates on nitrogen-limited ecosystems are poorly understood, we investigated the surface-atmosphere exchange of several nitrogen and carbon compounds using multiple high-resolution measurement techniques and modeling. Our study site was a protected semi-natural bog ecosystem. Local wind regime and land use in the adjacent area clearly regulated whether total reactive nitrogen (ΣNr) concentrations were ammonia (NH3) or NOx-dominated. Eddy-covariance measurements of NH3 and ΣNr revealed concentration, temperature and surface wetness-dependent deposition rates. Intermittent periods of NH3 and ΣNr emission likely attributed to surface water re-emission and soil efflux, respectively, were found, thereby indicating nitrogen oversaturation in this originally N-limited ecosystem. Annual dry plus wet deposition resulted in 20 to 25 kg N ha-1 depending on method and model used, which translated into a four- to fivefold exceedance of the ecosystem-specific critical load. As the bog site had likely been exposed to the observed atmospheric nitrogen burden over several decades, a shift in grass species' composition towards a higher number of nitrophilous plants was already visible. Three years of CO2 eddy flux measurements showed that the site was a small net sink in the range of 33 to 268 g CO2 m-2 yr-1. Methane emissions of 32 g CO2-eq were found to partly offset the sequestered carbon through CO2. Our study indicates that the sink strength of the peatland has likely been decreased through elevated N deposition over the past decades. It also demonstrates the applicability of novel micrometeorological measurement techniques in biogeochemical sciences and stresses the importance of monitoring long-term changes in vulnerable ecosystems under anthropogenic pressure and climate change.

  18. Temperature and Burnup Correlated FCCI in U-10Zr Metallic Fuel

    Energy Technology Data Exchange (ETDEWEB)

    William J. Carmack

    2012-05-01

    Metallic fuels are proposed for use in advanced sodium cooled fast reactors. The experience basis for metallic fuels is extensive and includes development and qualification of fuels for the Experimental Breeder Reactor I, the Experimental Breeder Reactor II, FERMI-I, and the Fast Flux Test Facility (FFTF) reactors. Metallic fuels provide a number of advantages over other fuel types in terms of fabricability, performance, recyclability, and safety. Key to the performance of all nuclear fuel systems is the resistance to “breach” and subsequent release of fission products and fuel constituents to the primary coolant system of the nuclear power plant. In metallic fuel, the experience is that significant fuel-cladding chemical (FCCI) interaction occurs and becomes prevalent at high power-high temperature operation and ultimately leads to fuel pin breach and failure. Empirical relationships for metallic fuel pin failure have been developed from a large body of in-pile and out of pile research, development, and experimentation. It has been found that significant in-pile acceleration of the FCCI rate is experienced over similar condition out-of-pile experiments. The study of FCCI in metallic fuels has led to the quantification of in-pile failure rates to establish an empirical time and temperature dependent failure limit for fuel elements. Up until now the understanding of FCCI layer formation has been limited to data generated in EBR-II experiments. This dissertation provides new FCCI data extracted from the MFF-series of metallic fuel irradiations performed in the FFTF. These fuel assemblies contain valuable information on the formation of FCCI in metallic fuels at a variety of temperature and burnup conditions and in fuel with axial fuel height three times longer than EBR-II experiments. The longer fuel column in the FFTF and the fuel pins examined have significantly different flux, power, temperature, and FCCI profiles than that found in similar tests conducted in

  19. Effects of Lignocellulosic Compounds on the Yield, Nanostructure and Reactivity of Soot from Fast Pyrolysis at High Temperatures

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Broström, Markus; Kling, Jens

    Gasification offers the utilization of biomass to a wide variety of applications such as heat, electricity, chemicals and transport fuels in an efficient and sustainable manner. High soot yields in the high-temperature entrained flow gasification lead to intensive gas cleaning and can cause...... reactor. The specific objectives of this study were to: (1) obtain knowledge about lignocellulosic compounds and monolignols influence on the yield, nanostructure, composition, and reactivity of soot during high-temperature gasification, (2) understand the influence of Soxhlet extraction on the soot...... reactivity and characteristics, and (3) determine the reaction conditions and fuel composition which minimize soot formation leading to the efficient operation of high-temperature gasification process....

  20. Pediatric Loss of Control Eating and High-Sensitivity C-Reactive Protein Concentrations.

    Science.gov (United States)

    Shank, Lisa M; Tanofsky-Kraff, Marian; Kelly, Nichole R; Schvey, Natasha A; Marwitz, Shannon E; Mehari, Rim D; Brady, Sheila M; Demidowich, Andrew P; Broadney, Miranda M; Galescu, Ovidiu A; Pickworth, Courtney K; Yanovski, Susan Z; Yanovski, Jack A

    2017-02-01

    Loss of control (LOC) eating in youth is associated with excess body weight and adiposity. After adjusting for fat mass, youth with LOC eating have higher blood pressure and higher low-density lipoprotein cholesterol compared to youth without LOC eating. Increased inflammation may account for this relationship, although few data have examined this hypothesis. Therefore, this study explored the association between LOC eating and high-sensitivity C-reactive protein (hsCRP), a marker of inflammation. We investigated hsCRP concentrations in relation to LOC eating in a convenience sample of 194 youth (age 14.3 ± 2.1 years; 63.9% female; BMI-z 1.64 ± 1.06). The presence of LOC eating in the past month was assessed by the Eating Disorder Examination interview. Serum hsCRP was measured by enzyme-linked immunosorbent assay. Adiposity was measured by air displacement plethysmography or dual-energy x-ray absorptiometry. We compared hsCRP in those with and without LOC eating in analyses accounting for sex, adiposity, height, depressive symptoms, and eating psychopathology. Youth with LOC eating had significantly greater hsCRP than youth without LOC eating (p = 0.02), after accounting for all covariates. The number of LOC eating episodes in the past month was positively associated with hsCRP (p = 0.01). The relationship between LOC eating and hsCRP was not mediated by depressive symptoms or eating psychopathology (ps > 0.05). Youth with disinhibited eating may manifest increased chronic inflammation. Those with LOC eating may be an important subgroup at risk for adverse health outcomes associated with both chronic inflammation and obesity. Future research should examine whether hsCRP concentrations mediate the relationship between LOC eating and its association with cardiometabolic risk.

  1. A high precision method for quantitative measurements of reactive oxygen species in frozen biopsies.

    Directory of Open Access Journals (Sweden)

    Kirsti Berg

    Full Text Available OBJECTIVE: An electron paramagnetic resonance (EPR technique using the spin probe cyclic hydroxylamine 1-hydroxy-3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine (CMH was introduced as a versatile method for high precision quantification of reactive oxygen species, including the superoxide radical in frozen biological samples such as cell suspensions, blood or biopsies. MATERIALS AND METHODS: Loss of measurement precision and accuracy due to variations in sample size and shape were minimized by assembling the sample in a well-defined volume. Measurement was carried out at low temperature (150 K using a nitrogen flow Dewar. The signal intensity was measured from the EPR 1st derivative amplitude, and related to a sample, 3-carboxy-proxyl (CP• with known spin concentration. RESULTS: The absolute spin concentration could be quantified with a precision and accuracy better than ±10 µM (k = 1. The spin concentration of samples stored at -80°C could be reproduced after 6 months of storage well within the same error estimate. CONCLUSION: The absolute spin concentration in wet biological samples such as biopsies, water solutions and cell cultures could be quantified with higher precision and accuracy than normally achievable using common techniques such as flat cells, tissue cells and various capillary tubes. In addition; biological samples could be collected and stored for future incubation with spin probe, and also further stored up to at least six months before EPR analysis, without loss of signal intensity. This opens for the possibility to store and transport incubated biological samples with known accuracy of the spin concentration over time.

  2. High-sensitivity C-reactive protein as a predictor of locally advanced renal cell carcinoma.

    Science.gov (United States)

    García-Marchiñena, Patricio; Billordo-Perés, Nicolas; Tobía-González, Ignacio; Jurado, Alberto; Damia, Oscar; Gueglio, Guillermo

    2012-01-01

    To determine if elevated levels of high-sensitivity C-reactive protein (CRP) in plasma are associated with locally advanced renal cell carcinoma (LARCC) after surgery. Retrospective cross-sectional study conducted from May 2009 to January 2011. Altogether, 192 patients with non-disseminated disease and with preoperative quantitative determination of the CRP were evaluated. We evaluated the relation between age, gender, history of smoking, symptoms and CRP higher than 10 mg/L, with LARCC. The chi-square and Fisher's tests were used to compare categorical variables. For the multivariate analysis, we used logistic regression methods. The median age was 62 years (r=23-85), 72.4% were males. The median CRP was 2.40 mg/L (r=0.1-173). Of all the patients, 43.2% had a history of smoking and 81.8% were asymptomatic. As for the tumors, 77.1%were clear cell carcinoma, 14.6% chromophobe, 4.7% papillary, 2.6% oncocytomas, and 1% other varieties of renal cell carcinoma. As for the TNM classification, 45.8% corresponded to stage pT1a, 27.6% pT1b, 13% pT2, and 13.5% pT3, pT4 was not found. In the multivariate analysis, the presence of symptoms (p=0.002, OR=3.1) and the presence of CRP higher than 10 mg/L (p=0.006, OR=4) remained as the only prognostic variables of LARCC. Values of CRP higher than 10 mg/L increase 4 times the possibilities of finding LARCC in the pathological study of the surgical specimen. This variable should be taken into account when deciding what is the best surgical option.

  3. House dust bioactivities predict skin prick test reactivity for children with high risk of allergy.

    Science.gov (United States)

    Kim, Haejin; Tse, Kevin; Levin, Linda; Bernstein, David; Reponen, Tiina; LeMasters, Grace; Lummus, Zana; Horner, Anthony A

    2012-06-01

    Although evidence suggests that ambient exposures to endotoxin and other immunostimulants during early life influence allergic risk, efforts to understand this host-environment relationship have been hampered by a paucity of relevant assays. These investigations determined whether parameters of house dust extract (HDE) bioactivity were predictive of allergen skin prick test (SPT) reactivity for infants at high risk of allergy participating in the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS). We conducted a nested case-control study, selecting 99 CCAAPS children who had positive SPT results to at least 1 aeroallergen at age 3 years and 101 subjects with negative SPT results. HDEs were prepared from dust samples collected from the subjects' homes at age 1 year. Murine splenocytes and bone marrow-derived dendritic cells were incubated with HDEs, and supernatant cytokine concentrations were determined by means of ELISA. Alternatively, bone marrow-derived dendritic cells were preincubated with HDEs, and then LPS-induced IL-6 responses were assessed. HDE endotoxin levels were determined by using the limulus amebocyte lysate assay. HDEs derived from the homes of children with positive (cases) and negative (control subjects) SPT results had similar bioactivities. However, when cases were considered in isolation, HDEs with higher levels of bioactivity were significantly associated with children who had lower numbers of positive SPT results. Analogous statistical analyses did not identify any association between HDE endotoxin levels and the aeroallergen sensitization profiles of children included in this study. HDE immunostimulatory activities predicted the aeroallergen sensitization status of CCAAPS subjects better than HDE endotoxin levels. These results provide the first published evidence that HDE bioassays have clinical relevance in predicting atopic risk. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All

  4. Aspirin and clopidogrel high on-treatment platelet reactivity and genetic predictors in peripheral arterial disease.

    Science.gov (United States)

    Yeo, Khung-Keong; Armstrong, Ehrin J; López, Javier E; Chen, Debbie C; Westin, Gregory G; Li, Chin-Shang; Anderson, David; Hua, Amy; Singapuri, Anil; Amsterdam, Ezra A; Chiamvimonvat, Nipavan; Laird, John R

    2018-02-07

    Our aims were to examine the prevalence and genetic predictors of aspirin and clopidogrel high on-treatment platelet reactivity (HoTPR), and associated adverse cardiovascular outcomes in patients with peripheral arterial disease (PAD). The association of aspirin and clopidogrel HoTPR with outcomes in PAD remains unclear. This is a prospective cohort study of patients with angiographically documented PAD involving carotid and lower extremity arteries. Aspirin and clopidogrel HoTPR (using the VerifyNow Assay) and associated genetic predictors were compared to clinical outcomes. The primary end-point was a composite of major adverse cardiovascular events: all-cause mortality, myocardial infarction, stroke, target vessel revascularization (TVR) and limb-loss in patients who underwent extremity intervention. The study was stopped prematurely due to slow patient enrolment. Of 195 patients enrolled, the primary analysis was performed in 154 patients taking both drugs. Aspirin HoTPR was present in 31 (20%) and clopidogrel HoTPR in 76 (49%) patients. There was a trend toward more primary composite outcome events with PRU ≥ 235 (52% freedom-from-event rate vs. 70% for PRU < 235; P = 0.09). TVR was higher in those with PRU ≥ 235 (20 vs. 6%, unadjusted P = 0.02). There was no association between aspirin HoTPR and combined outcomes. Single nucleotide polymorphisms in serum paraoxonase/arylesterase 1 (PON1) gene was associated with aspirin HoTPR (P = 0.005) while SNP in phospholipase A2, group III (PLA2G3) gene was associated with clopidogrel HoTPR (P = 0.002). Clopidogrel HoTPR was significantly associated with TVR, while aspirin HoTPR was not associated with adverse clinical outcomes in patients with PAD. © 2018 Wiley Periodicals, Inc.

  5. High-resolution fingerprints of past landsliding and spatially explicit, probabilistic assessment of future reactivations: Aiguettes landslide, Southeastern French Alps

    Science.gov (United States)

    Lopez Saez, Jérôme; Corona, Christophe; Stoffel, Markus; Berger, Frédéric

    2013-08-01

    The purpose of this study was to reconstruct spatio-temporal patterns of past landslide reactivation and the possible occurrence of future events in a forested area of the Barcelonnette basin (Southeastern French Alps). Analysis of past events on the Aiguettes landslide was based on growth-ring series from 223 heavily affected Mountain pine (Pinus uncinata Mill. ex Mirb.) trees growing on the landslide body. A total of 355 growth disturbances were identified in the samples indicating 14 reactivation phases of the landslide body since AD 1898. Accuracy of the spatio-temporal reconstruction is confirmed by historical records and aerial photographs. Logistic regressions using monthly rainfall data from the HISTALP database indicated that landslide reactivations occurred due to above-average precipitation anomalies in winter. They point to the important role of snow in the triggering of reactivations at the Aiguettes landslide body. In a subsequent step, spatially explicit probabilities of landslide reactivation were computed based on the extensive dendrogeomorphic dataset using a Poisson distribution model for an event to occur in 5, 20, 50, and 100 yr. High-resolution maps indicate highest probabilities of reactivation in the lower part of the landslide body and increase from 0.28 for a 5-yr period to 0.99 for a 100-yr period. In the upper part of the landslide body, probabilities do not exceed 0.57 for a 100-yr period and somehow confirm the more stable character of this segment of the Aiguettes landslide. The approach presented in this paper is considered a valuable tool for land-use planners and emergency cells in charge of forecasting future events and in protecting people and their assets from the negative effects of landslides.

  6. Men with high serotonin 1B receptor binding respond to provocations with heightened amygdala reactivity

    DEFF Research Database (Denmark)

    da Cunha-Bang, Sofi; Fisher, Patrick M; Hjordt, Liv V

    2018-01-01

    Serotonin signalling influences amygdala reactivity to threat-related emotional facial expressions in healthy adults, but in vivo serotonin signalling has never been investigated in the context of provocative stimuli in aggressive individuals. The aim of this study was to evaluate associations...... (LV1B) modelling shared correlation between 5-HT1BR binding across multiple brain regions (neocortex, anterior and posterior cingulate cortex, raphe, amygdala, hippocampus and striatum). We tested whether the LV1B was associated with amygdala, striatal and prefrontal reactivity to provocations......, adjusting for age, injected mass and group. Across participants, LV1B was statistically significantly positively associated with amygdala (p = 0.01) but not with striatal (p = 0.2) or prefrontal reactivity to provocations (p = 0.3). These findings provide novel evidence that 5-HT1BR levels are linked...

  7. High efficiency H6 single-phase transformerless grid-tied PV inverter with proposed modulation for reactive power generation

    Science.gov (United States)

    Almasoudi, Fahad M.; Alatawi, Khaled S.; Matin, Mohammad

    2017-08-01

    Implementation of transformerless inverters in PV grid-tied system offer great benefits such as high efficiency, light weight, low cost, etc. Most of the proposed transformerless inverters in literature are verified for only real power application. Currently, international standards such as VDE-AR-N 4105 has demanded that PV grid-tied inverters should have the ability of controlling a specific amount of reactive power. Generation of reactive power cannot be accomplished in single phase transformerless inverter topologies because the existing modulation techniques are not adopted for a freewheeling path in the negative power region. This paper enhances a previous high efficiency proposed H6 trnasformerless inverter with SiC MOSFETs and demonstrates new operating modes for the generation of reactive power. A proposed pulse width modulation (PWM) technique is applied to achieve bidirectional current flow through freewheeling state. A comparison of the proposed H6 transformerless inverter using SiC MOSFETs and Si MOSFTEs is presented in terms of power losses and efficiency. The results show that reactive power control is attained without adding any additional active devices or modification to the inverter structure. Also, the proposed modulation maintains a constant common mode voltage (CM) during every operating mode and has low leakage current. The performance of the proposed system verifies its effectiveness in the next generation PV system.

  8. [High sensitivity C reactive protein and lipid status as a risk factors for coronary disease].

    Science.gov (United States)

    Nurkić, Jasmina; Nurkić, Mahmud; Nurkić, Midhat

    2007-01-01

    It is generally accepted that inflammation has an important role, not just in the pathogenesis of atherosclerosis, but also in initiation of acute coronary syndrome (ACS). A number of studies showed, that a high concentration of high sensitivity C reactive protein (hsCRP) is an independent risk factor for the development of cardiovascular disease in a healthy person. HsCRP can predict new cardiovascular episodes, including death, in patients with unstable angina and acute myocardial infarction (AMI). Ability of oxidated low densiti lipoprotein (oxLDL) to induce accumulation of holesterol in macrofage was his first described proaterogenic characteristic and it help in hipotesis that oxidation of low densiti lipoprotein (LDL) can be important step in proces of aterogenesis. Framingham study showed that ther is significant corelation between level of total holesterol in blood and coronary artery disease (CAD). Evaluation of bouth hsCRP and LDL levels is superior in detection of CAD. Aims of this study were to determine values of hsCRP in patients with coronary arteries disease verified by coronary angiography (stenosis>70%), and to check if values of hsCRP higher than 3.0 mg/ dL are better predictor of coronary artery disease then lipid status. A prospective study was conducted on 60 patients, who were divided in two groups in compliance with significance of coronary artery disease. All patients have earlier diagnosis of ACS, and from this study excluded patients with acute infection, chronic, systemic or malignant disease. This research shows that patients with significant coronary artery disease, verified by coronary angiography, have higher values of hsCRP than those without disease that have values within the range of the reference values (0-3 mg/dL). Patients with coronary artery disease verified by coronary angiography have values of hsCRP that put them in a group of patients with intermediate to high risk of a future acute cardiovascular event, by

  9. Reactive power compensation considering high harmonics generation from internal and external nonlinear load

    Science.gov (United States)

    Skamyin, A. N.; Belsky, A. A.

    2017-10-01

    The paper deals with reactive power compensation by means of condenser batteries with harmonic distortions in voltage and current, resulting from internal and external nonlinear load regarding the connection point shared by consumers. The paper presents the dependencies of the capacitor’s overloading factor from the required reactive power for compensating. These relations can help to determine in which capacity area of the capacitor banks its operation is ensured without overload. The paper also presents algorithm for selecting parameters of condenser batteries which leads to minimization of the capacitors overload and maximization of the network power factor.

  10. Electrochemical Interphases for High-Energy Storage Using Reactive Metal Anodes

    KAUST Repository

    Wei, Shuya

    2017-12-11

    Conspectus Stable electrochemical interphases play a critical role in regulating transport of mass and charge in all electrochemical energy storage (EES) systems. In state-of-the-art rechargeable lithium ion batteries, they are rarely formed by design but instead spontaneously emerge from electrochemical degradation of electrolyte and electrode components. High-energy secondary batteries that utilize reactive metal anodes (e.g., Li, Na, Si, Sn, Al) to store large amounts of charge by alloying and/or electrodeposition reactions introduce fundamental challenges that require rational design in order to stabilize the interphases. Chemical instability of the electrodes in contact with electrolytes, morphological instability of the metal–electrolyte interface upon plating and stripping, and hydrodynamic-instability-induced electroconvection of the electrolyte at high currents are all known to cause metal electrode–electrolyte interfaces to continuously evolve in morphology, uniformity, and composition. Additionally, metal anodes undergo large changes in volume during lithiation and delithiation, which means that even in the rare cases where spontaneously formed solid electrode–electrolyte interphases (SEIs) are in thermodynamic equilibrium with the electrode, the SEI is under dynamic strain, which inevitably leads to cracking and/or rupture during extended battery cycling. There is an urgent need for interphases that are able to overcome each of these sources of instability with minimal losses of electrolyte and electrode components. Complementary chemical synthesis strategies are likewise urgently needed to create self-limited and mechanically durable SEIs that are able to flex and shrink to accommodate volume change. These needs are acute for practically relevant cells that cannot utilize large excesses of anode and electrolyte as employed in proof-of-concept-type experiments reported in the scientific literature. This disconnect between practical needs and

  11. Comparison of Reactive and Non-Reactive Spark Plasma Sintering Routes for the Fabrication of Monolithic and Composite Ultra High Temperature Ceramics (UHTC Materials

    Directory of Open Access Journals (Sweden)

    Roberto Orrù

    2013-04-01

    Full Text Available A wider utilization of ultra high temperature ceramics (UHTC materials strongly depends on the availability of efficient techniques for their fabrication as dense bodies. Based on recent results reported in the literature, it is possible to state that Spark Plasma Sintering (SPS technology offers a useful contribution in this direction. Along these lines, the use of two different SPS-based processing routes for the preparation of massive UHTCs is examined in this work. One method, the so-called reactive SPS (R-SPS, consists of the synthesis and densification of the material in a single step. Alternatively, the ceramic powders are first synthesized by Self-propagating High-temperature Synthesis (SHS and then sintered by SPS. The obtained results evidenced that R-SPS method is preferable for the preparation of dense monolithic products, while the sintering of SHS powders requires relatively milder conditions when considering binary composites. The different kinetic mechanisms involved during R-SPS of the monolithic and composite systems, i.e., combustion-like or gradual solid-diffusion, respectively, provides a possible explanation. An important role is also played by the SHS process, particularly for the preparation of composite powders, since stronger interfaces are established between the ceramic constituents formed in situ, thus favoring diffusion processes during the subsequent SPS step.

  12. Violent offenders respond to provocations with high amygdala and striatal reactivity

    DEFF Research Database (Denmark)

    da Cunha-Bang, Sofi; Fisher, Patrick M.; Hjordt, Liv Vadskjær

    2017-01-01

    monetary rewards. The violent offenders behaved more aggressively than controls (aggression frequency 150 us 84, P = 0.03) and showed significantly higher brain reactivity to provocations within the amygdala and striatum, as well as reduced amygdala-prefrontal and striato-prefrontal connectivity. Amygdala...

  13. Plasma high sensitivity C-reactive protein as a marker of severity in ...

    African Journals Online (AJOL)

    Ehab

    activation during DKA and its treatment.10. C-reactive protein (CRP) is a type I acute phase response ... pancreatitis or acute/chronic infection. Acute infection was ruled out after a thorough medical history and clinical examination by the pediatrician as well as a sequential evaluation in the pediatric department after the ...

  14. Platelet Larger Cell Ratio and High-on Treatment Platelet Reactivity During Dual Antiplatelet Therapy

    NARCIS (Netherlands)

    Verdoia, M.; Pergolini, P.; Rolla, R.; Nardin, M.; Barbieri, L.; Schaffer, A.; Bellomo, G.; Marino, P.; Suryapranata, H.; Luca, G. De

    2015-01-01

    BACKGROUND: Low response to antiplatelet agents has been associated to an increased risk of thrombotic complications and recurrent ischemic events. Platelet size has been proposed as a potential marker of platelet reactivity. Therefore, the aim of the present study was to evaluate the impact of

  15. Mg-aminoclay as stabilizer for synthesizing highly stable and reactive nZVI for decontamination

    DEFF Research Database (Denmark)

    Hwang, Yuhoon; Lee, Young-Chul; Mines, Paul D.

    Despite the large surface area and superior reactivity of nZVI, its limited stability is a major obstacle for in situ subsurface remediation. In this study, Mg-aminoclay (MgAC) was applied for the first time as a stabilizer in nZVI synthesis. With increased doses of Mg-aminoclay, nZVI particle gr...

  16. Microcontact Printing onto Oxide-Free Silicon via Highly Reactive Acid Fluoride-Functionalized Monolayers

    NARCIS (Netherlands)

    Scheres, L.M.W.; Maat, ter J.; Giesbers, M.; Zuilhof, H.

    2010-01-01

    This work describes a new route for patterning organic monolayers on oxide-free silicon by microcontact printing (µCP) on a preformed, reactive, acid-fluoride-terminated monolayer. This indirect printing approach is fast and easily preserves the oxide-free and well-defined monolayer-silicon

  17. Gliadin-reactive T cells in Italian children from preventCD cohort at high risk of celiac disease.

    Science.gov (United States)

    Camarca, Alessandra; Auricchio, Renata; Picascia, Stefania; Fierro, Olga; Maglio, Mariantonia; Miele, Erasmo; Malamisura, Basilio; Greco, Luigi; Troncone, Riccardo; Gianfrani, Carmen

    2017-06-01

    Newborns at high risk of celiac disease (CD) were recruited in Italy in the context of the PreventCD study and closely monitored for CD, from 4 months up to a mean age of 8 years at follow-up. The aim of our study was to investigate intestinal T-cell reactivity to gliadin at the first clinical and/or serological signs of CD. Gliadin-reactive T-cell lines were generated from intestinal biopsies of 19 HLA-DQ2-or HLA-DQ8-positive children. At biopsy, 11 children had a diagnosis of acute CD, two of potential CD, and six were non-celiac controls. Immune reactivity was evaluated against gliadin and known immunogenic peptides from α-, γ-, or ω-gliadins. The role of deamidation by transglutaminase (tTG) in determining the immunogenicity of gliadin was also investigated. Most of the children with CD (either acute or potential) had an inflammatory response to gliadin. Notably, signs of T-cell reactivity to gliadin were also found in some non-celiac subjects, in which IFN-γ responses occurred mainly when regulatory IL-10 and TGF-β cytokines were blocked. Interestingly, PreventCD children reacted to gliadin peptides found active in adult CD patients, and tTG deamidation markedly enhanced gliadin recognition. T cells reactive to gliadin can be detected in the intestine of children at high risk of developing CD, in some cases also in the presence of a normal mucosa and negative CD-associated antibodies. Furthermore, children at a very early stage of CD recognize the same gliadin epitopes that are active in adult CD patients. Tissue transglutaminase strongly enhances gluten T-cell immunogenicity in early CD. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  18. Characterization of combined power plasma jet using AC high voltage and nanosecond pulse for reactive species composition control

    Science.gov (United States)

    Takashima, Keisuke; Konishi, Hideaki; Kato, Toshiaki; Kaneko, Toshiro

    2014-10-01

    In the application studies for both bio-medical and agricultural applications, the roles of the reactive oxide and/or nitride species generated in the plasma has been reported as a key to control the effects and ill-effects on the living organism. The correlation between total OH radical exposure from an air atmospheric pressure plasma jet and the sterilization threshold on Botrytis cinerea is presented. With the increase of the OH radical exposure to the Botrytis cinerea, the probability of sterilization is increased. In this study, to resolve the roles of reactive species including OH radicals, a combined power plasma jet using nanosecond pulses and low-frequency sinusoidal AC high voltage (a few kHz) is studied for controlling the composition of the reactive species. The nanosecond pulses are superimposed on the AC voltage which is in synchronization with the AC phase. The undergoing work to characterize the combined power discharge with electric charge and voltage cycle on the plasma jet will also be presented to discuss the discharge characteristics to control the composition of the reactive species.

  19. Group Constants Generation of the Pseudo Fission Products for Fast Reactor Burnup Calculations

    Science.gov (United States)

    Gil, Choong-Sup; Kim, Do Heon; Chang, Jonghwa

    2005-05-01

    The pseudo fission products for the burnup calculations of the liquid metal fast reactor were generated. The cross-section data and fission product yield data of ENDF/B-VI were used for the pseudo fission product data of U-235, U-238, Pu-239, Pu-240, Pu-241, and Pu-242. The pseudo fission product data can be used with the KAFAX-F22 or -E66, which are the MATXS-format libraries for analyses of the liquid metal fast reactor at KAERI and were distributed through the OECD/NEA. The 80-group MATXS-format libraries of the 172 fission products were generated and the burnup chains for generation of the pseudo fission products were prepared.

  20. High leukocyte count and interleukin-10 predict high on-treatment-platelet-reactivity in patients treated with clopidogrel.

    Science.gov (United States)

    Osmancik, Pavel; Paulu, Petra; Tousek, Petr; Kocka, Viktor; Widimsky, Petr

    2012-05-01

    According to recent trials, a significant number of patients do not have a completely effective response to clopidogrel. The aim of the study was to evaluate the rate of clopidogrel resistance in the context of important clinical characteristics and to specifically determine the relation between clopidogrel efficacy and biomarkers of inflammation. Consecutive non-selected patients following PCI were enrolled into the study. All patients received a loading dose of 600 mg of clopidogrel. The effect of clopidogrel was assessed using the VerifyNow assay 24 h after clopidogrel administration, clopidogrel resistance was defined as PRU ≥ 240. At the same time, standard parameters of biochemistry and hematology, the concentration of anti-inflammatory cytokine interleukin-10 and of soluble CD40 ligand, were measured. 378 patients were enrolled. 243 (64.3%) patients were responders (R) and 135 patients (35.7%) were non-responders (NR). Non-responders were older (R 65.7 ± 13.3, NR 69.8 ± 11.5, P leukocyte count (R 9.8 ± 3.5, NR 11.7 ± 12.8, P leukocytes and IL-10 were associated with an increased risk for being a non-responder. Older, obese patients, especially women had a higher risk of high on-treatment-platelet-reactivity. Higher concentrations of leukocytes and interleukin-10 were also an important factor associated with the risk of low clopidogrel responsiveness.

  1. Single-point reactive power control method on voltage rise mitigation in residential networks with high PV penetration

    DEFF Research Database (Denmark)

    Hasheminamin, Maryam; Agelidis, Vassilios; Ahmadi, Abdollah

    2018-01-01

    Voltage rise (VR) due to reverse power flow is an important obstacle for high integration of Photovoltaic (PV) into residential networks. This paper introduces and elaborates a novel methodology of an index-based single-point-reactive power-control (SPRPC) methodology to mitigate voltage rise by ...... system with high r/x ratio. Efficacy, effectiveness and cost study of SPRPC is compared to droop control to evaluate its advantages....... by absorbing adequate reactive power from one selected point. The proposed index utilizes short circuit analysis to select the best point to apply this Volt/Var control method. SPRPC is supported technically and financially by distribution network operator that makes it cost effective, simple and efficient...

  2. Development of Highly Durable and Reactive Regenerable Magnesium-Based Sorbents for CO2 Separation in Coal Gasification Process

    Energy Technology Data Exchange (ETDEWEB)

    Javad Abbasian; Armin Hassanzadeh Khayyat; Rachid B. Slimane

    2005-06-01

    The specific objective of this project was to develop physically durable and chemically regenerable MgO-based sorbents that can remove carbon dioxide from raw coal gas at operating condition prevailing in IGCC processes. A total of sixty two (62) different sorbents were prepared in this project. The sorbents were prepared either by various sol-gel techniques (22 formulations) or modification of dolomite (40 formulations). The sorbents were prepared in the form of pellets and in granular forms. The solgel based sorbents had very high physical strength, relatively high surface area, and very low average pore diameter. The magnesium content of the sorbents was estimated to be 4-6 % w/w. To improve the reactivity of the sorbents toward CO{sub 2}, The sorbents were impregnated with potassium salts. The potassium content of the sorbents was about 5%. The dolomite-based sorbents were prepared by calcination of dolomite at various temperature and calcination environment (CO{sub 2} partial pressure and moisture). Potassium carbonate was added to the half-calcined dolomite through wet impregnation method. The estimated potassium content of the impregnated sorbents was in the range of 1-6% w/w. In general, the modified dolomite sorbents have significantly higher magnesium content, larger pore diameter and lower surface area, resulting in significantly higher reactivity compared to the sol-gel sorbents. The reactivities of a number of sorbents toward CO{sub 2} were determined in a Thermogravimetric Analyzer (TGA) unit. The results indicated that at the low CO{sub 2} partial pressures (i.e., 1 atm), the reactivities of the sorbents toward CO{sub 2} are very low. At elevated pressures (i.e., CO{sub 2} partial pressure of 10 bar) the maximum conversion of MgO obtained with the sol-gel based sorbents was about 5%, which corresponds to a maximum CO{sub 2} absorption capacity of less than 1%. The overall capacity of modified dolomite sorbents were at least one order of magnitude

  3. High-Frequency Heart Rate Variability Reactivity and Trait Worry Interact to Predict the Development of Sleep Disturbances in Response to a Naturalistic Stressor.

    Science.gov (United States)

    MacNeil, Sasha; Deschênes, Sonya S; Caldwell, Warren; Brouillard, Melanie; Dang-Vu, Thien-Thanh; Gouin, Jean-Philippe

    2017-12-01

    High-frequency heart rate variability (HF-HRV) reactivity was proposed as a vulnerability factor for stress-induced sleep disturbances. Its effect may be amplified among individuals with high trait worry or sleep reactivity. This study evaluated whether HF-HRV reactivity to a worry induction, sleep reactivity, and trait worry predict increases in sleep disturbances in response to academic stress, a naturalistic stressor. A longitudinal study following 102 undergraduate students during an academic semester with well-defined periods of lower and higher academic stress was conducted. HF-HRV reactivity to a worry induction, trait worry using the Penn State Worry Questionnaire, and sleep reactivity using the Ford Insomnia Stress Reactivity Test were measured during the low stress period. Sleep disturbances using the Pittsburgh Sleep Quality Index were assessed twice during the lower stress period and three times during the higher stress period. Greater reductions in HF-HRV in response to the worry induction predicted increases in sleep disturbances from the lower to the higher academic stress period. Trait worry moderated this association: individuals with both higher trait worry and greater HF-HRV reactivity to worry had larger increases in stress-related sleep disturbances over time, compared to participants with lower trait worry and HF-HRV reactivity. A similar, but marginally significant effect was found for sleep reactivity. This study supports the role of HF-HRV reactivity as a vulnerability factor for stress-induced sleep disturbances. The combination of high trait worry and high HF-HRV reactivity to worry might identify a subgroup of individuals most vulnerable to stress-related sleep disturbances.

  4. High-sensitivity Lens culinaris agglutinin-reactive alpha-fetoprotein assay predicts early detection of hepatocellular carcinoma

    OpenAIRE

    Kumada, Takashi; Toyoda, Hidenori; Tada, Toshifumi; Kiriyama, Seiki; Tanikawa, Makoto; Hisanaga, Yasuhiro; Kanamori, Akira; Tanaka, Junko; Kagebayashi, Chiaki; Satomura, Shinji

    2013-01-01

    Background Prognosis of patients with hepatocellular carcinoma (HCC) remains poor because HCC is frequently diagnosed late. Therefore, regular surveillance has been recommended to detect HCC at the early stage when curative treatments can be applied. HCC biomarkers, including Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3), are widely used for surveillance in Japan. A newly developed immunoassay system measures AFP-L3 % with high sensitivity. This retrospective study...

  5. Large-scale reactive molecular dynamics simulation and kinetic modeling of high-temperature pyrolysis of the Gloeocapsomorphaprisca microfossils.

    Science.gov (United States)

    Zou, Chenyu; Raman, Sumathy; van Duin, Adri C T

    2014-06-12

    The ability to predict accurately the thermal conversion of complex carbonaceous materials is of value in both petroleum exploration and refining operations. Modeling the thermal cracking of kerogen under basinal heating conditions improves the predrill prediction of oil and gas yields and quality, thereby ultimately lowering the exploration risk. Modeling the chemical structure and reactivity of asphaltene from petroleum vacuum residues enables prediction of coke formation and properties in refinery processes, thereby lowering operating cost. The chemical structure-chemical yield modeling (CS-CYM) developed by Freund et al. is more rigorous, time-consuming, and requires a great deal of chemical insight into reaction network and reaction kinetics. The present work explores the applicability of a more fundamental atomistic simulation using the quantum mechanically based reactive force field to predict the product yield and overall kinetics of decomposition of two biopolymers, namely, the Kukersite and Gutternberg. Reactive molecular dynamics (RMD) simulations were performed on systems consisting of 10(4) to 10(5) atoms at different densities and temperatures to derive the overall kinetic parameters and a lumped kinetic model for pyrolysis. The kinetic parameters derived from the simulated pyrolysis of an individual component and the mixture of all four components in Guttenberg reveal the role of cross-talk between the fragments and enhanced reactivity of component A by radicals from other components. The Arrhenius extrapolation of the model yields reasonable prediction for the overall barrier for cracking. Because simulations were run at very high temperature (T > 1500 K) to study cracking within the simulation time of up to 1 ns, it, however, led to the entropically favored ethylene formation as a dominant decomposition route. Future work will focus on evaluating the applicability of accelerated reactive MD approaches to study cracking.

  6. Criticality Uncertainty Analysis of Spent Fuel Transport Cask applying Burnup Credit

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Gang Ug; Park, Jae Ho; Kim, Do Hyun [Korea Nuclear Engineering and Service Corp, Daejeon (Korea, Republic of); Kim, Tae Man; Yoon, Jeong Hyun [Korea Radioactive Waste Management Corporation, Daejeon (Korea, Republic of)

    2011-09-15

    In general, conventional criticality analyses for spent fuel transport/dry storage systems have been performed based on assumption of fresh fuel concerning the potential uncertainties from number density calculation of Transuranic and Fission Products in spent fuel. However, because of economic loss due to the excessive criticality margin, recently the design of transport/dry storage systems with Burnup Credit(BUC) application has been actively developed. The uncertainties in criticality analyses on transport/storage systems with BUC technique show strong dependence upon initial enrichment and burnup rate, whereas those in the conventional criticality evaluation based on fresh fuel assumption do not show such a dependence. In this study, regulatory-required uncertainties of the criticality analyses for BK 26 Cask, which is conceptually designed spent fuel transport cask with BUC corresponding to the limiting circumstances on nuclear power plants in Korea, are evaluated as a function of initial enrichment and burnup rate. Results of this study will be used as basic data for spent fuel loading curve of BK 26 Cask.

  7. Burnup simulations of different fuel grades using the MCNPX Monte Carlo code

    Directory of Open Access Journals (Sweden)

    Asah-Opoku Fiifi

    2014-01-01

    Full Text Available Global energy problems range from the increasing cost of fuel to the unequal distribution of energy resources and the potential climate change resulting from the burning of fossil fuels. A sustainable nuclear energy would augment the current world energy supply and serve as a reliable future energy source. This research focuses on Monte Carlo simulations of pressurized water reactor systems. Three different fuel grades - mixed oxide fuel (MOX, uranium oxide fuel (UOX, and commercially enriched uranium or uranium metal (CEU - are used in this simulation and their impact on the effective multiplication factor (Keff and, hence, criticality and total radioactivity of the reactor core after fuel burnup analyzed. The effect of different clad materials on Keff is also studied. Burnup calculation results indicate a buildup of plutonium isotopes in UOX and CEU, as opposed to a decline in plutonium radioisotopes for MOX fuel burnup time. For MOX fuel, a decrease of 31.9% of the fissile plutonium isotope is observed, while for UOX and CEU, fissile plutonium isotopes increased by 82.3% and 83.8%, respectively. Keff results show zircaloy as a much more effective clad material in comparison to zirconium and stainless steel.

  8. Preparation of higher-actinide burnup and cross section samples. [LMFBR

    Energy Technology Data Exchange (ETDEWEB)

    Adair, H.L.; Kobisk, E.H.; Quinby, T.C.; Thomas, D.K.; Dailey, J.M.

    1981-01-01

    A joint research program involving the United States and the United Kingdom was instigated about four years ago for the purpose of studying burnup of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of cross sections of a wide variety of higher actinide isotopes was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the burnup and cross section samples. The higher actinide samples chosen for the burnup study were /sup 241/Am and /sup 244/Cm in the forms of Am/sub 2/O/sub 3/, Cm/sub 2/O/sub 3/, and Am/sub 6/ Cm(RE)/sub 7/O/sub 21/, where (RE) represents a mixture of lanthanide sesquioxides. It is the purpose of this paper to describe technology development and its application in the preparation of the fuel specimens and the cross section specimens that are being used in this cooperative program.

  9. Thermal Hydraulic Analysis of 3 MW TRIGA Research Reactor of Bangladesh Considering Different Cycles of Burnup

    Directory of Open Access Journals (Sweden)

    M.H. Altaf

    2014-12-01

    Full Text Available Burnup dependent steady state thermal hydraulic analysis of TRIGA Mark-II research reactor has been carried out utilizing coupled point kinetics, neutronics and thermal hydraulics code EUREKA-2/RR. From the previous calculations of neutronics parameters including percentage burnup of individual fuel elements performed so far for 700 MWD burnt core of TRIGA reactor showed that the fuel rod predicted as hottest at the beginning of cycle (fresh core was found to remain as the hottest until 200 MWD of burn, but, with the progress of core burn, the hottest rod was found to be shifted and another rod in the core became the hottest. The present study intends to evaluate the thermal hydraulic parameters of these hottest fuel rods at different cycles of burnup, from beginning to 700 MWD core burnt considering reactor operates under steady state condition. Peak fuel centerline temperature, maximum cladding and coolant temperatures of the hottest channels were calculated. It revealed that maximum temperature reported for fuel clad and fuel centerline found to lie below their melting points which indicate that there is no chance of burnout on the fuel cladding surface and no blister in the fuel meat throughout the considered cycles of core burnt.

  10. Irradiation performance of PFBR MOX fuel after 112 GWd/t burn-up

    Energy Technology Data Exchange (ETDEWEB)

    Venkiteswaran, C.N., E-mail: cnv@igcar.gov.in; Jayaraj, V.V.; Ojha, B.K.; Anandaraj, V.; Padalakshmi, M.; Vinodkumar, S.; Karthik, V.; Vijaykumar, Ran; Vijayaraghavan, A.; Divakar, R.; Johny, T.; Joseph, Jojo; Thirunavakkarasu, S.; Saravanan, T.; Philip, John; Rao, B.P.C.; Kasiviswanathan, K.V.; Jayakumar, T.

    2014-06-01

    The 500 MWe Prototype Fast Breeder Reactor (PFBR) which is in advanced stage of construction at Kalpakkam, India, will use mixed oxide (MOX) fuel with a target burnup of 100 GWd/t. The fuel pellet is of annular design to enable operation at a peak linear power of 450 W/cm with the requirement of minimum duration of pre-conditioning. The performance of the MOX fuel and the D9 clad and wrapper material was assessed through Post Irradiation Examinations (PIE) after test irradiation of 37 fuel pin subassembly in Fast Breeder Test Reactor (FBTR) to a burn-up of 112 GWd/t. Fission product distribution, swelling and fuel–clad gap evolution, central hole diameter variation, restructuring, fission gas release and clad wastage due to fuel–clad chemical interaction were evaluated through non-destructive and destructive examinations. The examinations have indicated that the MOX fuel can safely attain the desired target burn-up in PFBR.

  11. Underestimation of nuclear fuel burnup – theory, demonstration and solution in numerical models

    Directory of Open Access Journals (Sweden)

    Gajda Paweł

    2016-01-01

    Full Text Available Monte Carlo methodology provides reference statistical solution of neutron transport criticality problems of nuclear systems. Estimated reaction rates can be applied as an input to Bateman equations that govern isotopic evolution of reactor materials. Because statistical solution of Boltzmann equation is computationally expensive, it is in practice applied to time steps of limited length. In this paper we show that simple staircase step model leads to underprediction of numerical fuel burnup (Fissions per Initial Metal Atom – FIMA. Theoretical considerations indicates that this error is inversely proportional to the length of the time step and origins from the variation of heating per source neutron. The bias can be diminished by application of predictor-corrector step model. A set of burnup simulations with various step length and coupling schemes has been performed. SERPENT code version 1.17 has been applied to the model of a typical fuel assembly from Pressurized Water Reactor. In reference case FIMA reaches 6.24% that is equivalent to about 60 GWD/tHM of industrial burnup. The discrepancies up to 1% have been observed depending on time step model and theoretical predictions are consistent with numerical results. Conclusions presented in this paper are important for research and development concerning nuclear fuel cycle also in the context of Gen4 systems.

  12. OECD/NEA burnup credit criticality benchmark. Result of phase IIA

    Energy Technology Data Exchange (ETDEWEB)

    Takano, Makoto; Okuno, Hiroshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    The report describes the final result of the Phase IIA of the Burnup Credit Criticality Benchmark conducted by OECD/NEA. In the Phase IIA benchmark problems, the effect of an axial burnup profile of PWR spent fuels on criticality (end effect) has been studied. The axial profiles at 10, 30 and 50 GWd/t burnup have been considered. In total, 22 results from 18 institutes of 10 countries have been submitted. The calculated multiplication factors from the participants have lain within the band of {+-} 1% {Delta}k. For the irradiation up to 30 GWd/t, the end effect has been found to be less than 1.0% {Delta}k. But, for the 50 GWd/t case, the effect is more than 4.0% {Delta}k when both actinides and FPs are taken into account, whereas it remains less than 1.0% {Delta}k when only actinides are considered. The fission density data have indicated the importance end regions have in the criticality safety analysis of spent fuel systems. (author).

  13. One-step uniformly hybrid carbon quantum dots with high-reactive TiO{sub 2} for photocatalytic application

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Wei [School of Physics and Optoelectronic Engineering, Nanjing University of Information Science and Technology, Nanjing 210044 (China); Ni, Yaru; Xu, Zhongzi [College of Materials Science and Engineering, Nanjing Tech University, Nanjing 210009 (China)

    2015-02-15

    Highlights: • CQDs were uniformly deposited on high-reactive TiO{sub 2} by a one-pot method. • CQDs can use a wide range of solar spectrum efficiently for photocatalysis. • TiO{sub 2} facets are not affected and the total photocatalytic activity was improved. - Abstract: High-reactive facets dominated anatase TiO{sub 2} is of great significance to solve environment and energy challenges. Maintaining the pristine structure and improving the photocatalytic activity of TiO{sub 2} still need innovation work by employing different modification processes. Here, carbon quantum dots (CQDs) were employed to modify TiO{sub 2} with exposed {0 0 1}, {1 0 1}, and {0 1 0} facets by a one-pot hydrothermal method. Results indicate that CQDs can disperse uniformly on TiO{sub 2} surface, and the high-reactive facets are maintained perfectly. The introduced CQDs can both enhance the light absorption and suppress photogenerated electron-hole’s recombination. Proper amount of introduced CQDs can both significantly enhance the photocatalytic activities, which are very stable, under the UV and visible light irradiation Corresponding photocatalytic mechanisms are also discussed in the present work.

  14. Reactive power generation in high speed induction machines by continuously occurring space-transients

    Science.gov (United States)

    Laithwaite, E. R.; Kuznetsov, S. B.

    1980-09-01

    A new technique of continuously generating reactive power from the stator of a brushless induction machine is conceived and tested on a 10-kw linear machine and on 35 and 150 rotary cage motors. An auxiliary magnetic wave traveling at rotor speed is artificially created by the space-transient attributable to the asymmetrical stator winding. At least two distinct windings of different pole-pitch must be incorporated. This rotor wave drifts in and out of phase repeatedly with the stator MMF wave proper and the resulting modulation of the airgap flux is used to generate reactive VA apart from that required for magnetization or leakage flux. The VAR generation effect increases with machine size, and leading power factor operation of the entire machine is viable for large industrial motors and power system induction generators.

  15. Cyclobutenone as a Highly Reactive Dienophile: Expanding Upon Diels-Alder Paradigms

    Science.gov (United States)

    Li, Xiaohua; Danishefsky, Samuel J.

    2010-01-01

    Cyclobutenone was employed as a dienophile in Diels-Alder cycloadditions which provided diverse complex cycloadducts in good yields. Experimental outcome indicated that cyclobutenone was more reactive in comparison with 2-cyclopentenone or 2-cyclohexenone. In addition, cycloadducts bearing strained cyclobutanone moiety were able to undergo regioselective ring expansions to produce corresponding cyclopentanones, lactones, and lactams, which otherwise were difficultly obtained by direct Diels-Alder reactions. PMID:20698657

  16. Comparison of high temperature chars of wheat straw and rice husk with respect to chemistry, morphology and reactivity

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Jensen, Peter Arendt; Jensen, Anker Degn

    2016-01-01

    Fast pyrolysis of wheat straw and rice husk was carried out in an entrained flow reactor at hightemperatures(1000e1500) C. The collected char was analyzed using X-ray diffractometry, N2-adsorption,scanning electron microscopy, particle size analysis with CAMSIZER XT, 29Si and 13C solid......-statenuclear magnetic resonance spectroscopy and thermogravimetric analysis to investigate the effect ofinorganic matter on the char morphology and oxygen reactivity. The silicon compounds were dispersedthroughout the turbostratic structure of rice husk char in an amorphous phase with a low meltingtemperature (z730 C......), which led to the formation of a glassy char shell, resulting in a preserved particlesize and shape of chars. The high alkali content in the wheat straw resulted in higher char reactivity,whereas the lower silicon content caused variations in the char shape from cylindrical to near...

  17. Modeling of PWR fuel at extended burnup; Estudo de modelos para o comportamento a altas queimas de varetas combustiveis de reatores a agua leve pressurizada

    Energy Technology Data Exchange (ETDEWEB)

    Dias, Raphael Mejias

    2016-11-01

    This work studies the modifications implemented over successive versions in the empirical models of the computer program FRAPCON used to simulate the steady state irradiation performance of Pressurized Water Reactor (PWR) fuel rods under high burnup condition. In the study, the empirical models present in FRAPCON official documentation were analyzed. A literature study was conducted on the effects of high burnup in nuclear fuels and to improve the understanding of the models used by FRAPCON program in these conditions. A steady state fuel performance analysis was conducted for a typical PWR fuel rod using FRAPCON program versions 3.3, 3.4, and 3.5. The results presented by the different versions of the program were compared in order to verify the impact of model changes in the output parameters of the program. It was observed that the changes brought significant differences in the results of the fuel rod thermal and mechanical parameters, especially when they evolved from FRAPCON-3.3 version to FRAPCON-3.5 version. Lower temperatures, lower cladding stress and strain, lower cladding oxide layer thickness were obtained in the fuel rod analyzed with the FRAPCON-3.5 version. (author)

  18. Prasugrel overcomes high on-clopidogrel platelet reactivity in the acute phase of acute coronary syndrome and maintains its antiplatelet potency at 30-day follow-up

    NARCIS (Netherlands)

    Kozinski, M.; Obonska, K.; Stankowska, K.; Navarese, E.P.; Fabiszak, T.; Stolarek, W.; Kasprzak, M.; Siller-Matula, J.M.; Rosc, D.; Kubica, J.; Servi, S. De

    2014-01-01

    BACKGROUND: The aim of this study was to assess antiplatelet effect of prasugrel in acute coronary syndrome (ACS) patients with high on-treatment platelet reactivity (HTPR) on clopidogrel, undergoing percutaneous coronary intervention (PCI). METHODS: A prospective, platelet reactivity-guided,

  19. Synthesis of Highly Reactive Subnano-sized Zero-valent Iron using Smectite Clay Templates

    Science.gov (United States)

    Gu, Cheng; Jia, Hanzhang; Li, Hui; Teppen, Brian J.; Boyd, Stephen A.

    2010-01-01

    A novel method was developed for synthesizing subnano-sized zero-valent iron (ZVI) using smectite clay layers as templates. Exchangeable Fe(III) cations compensating the structural negative charges of smectites were reduced with NaBH4, resulting in the formation of ZVI. The unique structure of smectite clay, in which isolated exchangeable Fe(III) cations reside near the sites of structural negative charges, inhibited the agglomeration of ZVI resulting in the formation of discrete regions of subnanoscale ZVI particles in the smectite interlayer regions. X-ray diffraction revealed an interlayer spacing of ~ 5 Å. The non-structural iron content of this clay yields a calculated ratio of two atoms of ZVI per three cation exchange sites, in full agreement with the XRD results since the diameter of elemental Fe is 2.5 Å. The clay-templated ZVI showed superior reactivity and efficiency compared to other previously reported forms of ZVI as indicated by the reduction of nitrobenzene; structural Fe within the aluminosilicate layers was nonreactive. At a 1:3 molar ratio of nitrobenzene:non-structural Fe, a reaction efficiency of 83% was achieved, and over 80% of the nitrobenzene was reduced within one minute. These results confirm that non-structural Fe from Fe(III)-smectite was reduced predominantly to ZVI which was responsible for the reduction of nitrobenzene to aniline. This new form of subnano-scale ZVI may find utility in the development of remediation technologies for persistent environmental contaminants, e.g. as components of constructed reactive domains such as reactive caps for contaminated sediments. PMID:20446730

  20. Synthesis of highly reactive subnano-sized zero-valent iron using smectite clay templates.

    Science.gov (United States)

    Gu, Cheng; Jia, Hanzhong; Li, Hui; Teppen, Brian J; Boyd, Stephen A

    2010-06-01

    A novel method was developed for synthesizing subnano-sized zero-valent iron (ZVI) using smectite clay layers as templates. Exchangeable Fe(III) cations compensating the structural negative charges of smectites were reduced with NaBH(4), resulting in the formation of ZVI. The unique structure of smectite clay, in which isolated exchangeable Fe(III) cations reside near the sites of structural negative charges, inhibited the agglomeration of ZVI resulting in the formation of subnanoscale ZVI particles in the smectite interlayer regions. X-ray diffraction revealed an interlayer spacing of approximately 5 A. The non-structural iron content of this clay yields a calculated ratio of two atoms of ZVI per three cation exchange sites, in full agreement with the X-ray diffraction (XRD) results since the diameter of elemental Fe is 2.5 A. The clay-templated ZVI showed superior reactivity and efficiency compared to other previously reported forms of ZVI as indicated by the reduction of nitrobenzene; structural Fe within the aluminosilicate layers was nonreactive. At a 1:3 molar ratio of nitrobenzene/non-structural Fe, a reaction efficiency of 83% was achieved, and over 80% of the nitrobenzene was reduced within one minute. These results confirm that non-structural Fe from Fe(III)-smectite was reduced predominantly to ZVI which was responsible for the reduction of nitrobenzene to aniline. This new form of subnanoscale ZVI may find utility in the development of remediation technologies for persistent environmental contaminants, for example, as components of constructed reactive domains such as reactive caps for contaminated sediments.

  1. Synthesis and characterization of high wash fastness novel azo reactive dyes incorporating aromatic bridged diamines

    OpenAIRE

    Aamer Saeed; Ghulam Shabir

    2018-01-01

    A new series of azo reactive dyes containing free chlorine atoms have been synthesized. The synthetic methodology involves the diazotization of 4′4-diamino diphenylamine-2-sulfonic acid (2) followed by azo coupling with 1-amino-8-naphthol-3,6-disulfonic acid (3) in alkaline medium to yield intermediate dye (4). Condensation of the latter with 1,3,5-trichlorotriazine afforded the cyanurated dye (5). A number of novel bis aromatic diamines (1a–j) were separately synthesized as bridging groups a...

  2. Overweight and Cognitive Performance: High Body Mass Index Is Associated with Impairment in Reactive Control during Task Switching

    Directory of Open Access Journals (Sweden)

    Laura Steenbergen

    2017-10-01

    Full Text Available The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI is associated with frontal lobe dysfunction and deficits in cognitive control. The present study aims to clarify the association between weight status and the degree of impairment in cognitive flexibility, i.e., the ability to efficiently switch from one task to another, by disentangling the preparatory and residual domains of task switching. Twenty-six normal weight (BMI < 25, five males and twenty-six overweight (BMI ≥ 25, seven males university students performed a task-switching paradigm that provides a relatively well-established diagnostic measure of proactive vs. reactive control with regard to cognitive flexibility. Compared to individuals with a BMI lower than 25, overweight (i.e., ≥25 was associated with increased switching costs in the reactive switching condition (i.e., when preparation time is short, representing reduced cognitive flexibility in the preparatory domain. In addition, the overweight group reported significantly more depression and binge eating symptoms, although still indicating minimal depression. No between-group differences were found with regard to self-reported autism spectrum symptoms, impulsiveness, state- and trait anxiety, and cognitive reactivity to depression. The present findings are consistent with and extend previous literature showing that elevated BMI in young, otherwise healthy individuals is associated with significantly more switching costs due to inefficiency in the retrieval, implementation, and maintenance of task sets, indicating less efficient cognitive control functioning.

  3. Overweight and Cognitive Performance: High Body Mass Index Is Associated with Impairment in Reactive Control during Task Switching.

    Science.gov (United States)

    Steenbergen, Laura; Colzato, Lorenza S

    2017-01-01

    The prevalence of weight problems is increasing worldwide. There is growing evidence that high body mass index (BMI) is associated with frontal lobe dysfunction and deficits in cognitive control. The present study aims to clarify the association between weight status and the degree of impairment in cognitive flexibility, i.e., the ability to efficiently switch from one task to another, by disentangling the preparatory and residual domains of task switching. Twenty-six normal weight (BMI switching paradigm that provides a relatively well-established diagnostic measure of proactive vs. reactive control with regard to cognitive flexibility. Compared to individuals with a BMI lower than 25, overweight (i.e., ≥25) was associated with increased switching costs in the reactive switching condition (i.e., when preparation time is short), representing reduced cognitive flexibility in the preparatory domain. In addition, the overweight group reported significantly more depression and binge eating symptoms, although still indicating minimal depression. No between-group differences were found with regard to self-reported autism spectrum symptoms, impulsiveness, state- and trait anxiety, and cognitive reactivity to depression. The present findings are consistent with and extend previous literature showing that elevated BMI in young, otherwise healthy individuals is associated with significantly more switching costs due to inefficiency in the retrieval, implementation, and maintenance of task sets, indicating less efficient cognitive control functioning.

  4. Electron transport and defect structure in highly conducting reactively sputtered ultrathin tin oxide films

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, Shikha; Pandya, Dinesh K., E-mail: dkpandya@physics.iitd.ac.in; Kashyap, Subhash C. [Thin Film Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2014-02-24

    Electrical conduction behavior of ultrathin (5–110 nm) SnO{sub 2} films reactively sputtered at 150–400 °C substrate temperatures is presented. The surface roughness studies revealed that the films with lower thickness were smoother (≤0.6 nm). Stoichiometry/defect structure of the films obtained from X-ray photoelectron spectroscopy data and electron mobility are found to be dependent on film thickness and substrate temperature. The observed increase in conductivity of semi-metallic films with decrease in film thickness is attributed to changes in defect structure and surface roughness. Highest value of conductivity of about 715 Ω{sup −1} cm{sup −1} is obtained for 5 nm thick films deposited at 300 °C.

  5. Enhanced Cisplatin Chemotherapy by Iron Oxide Nanocarrier-Mediated Generation of Highly Toxic Reactive Oxygen Species.

    Science.gov (United States)

    Ma, Ping'an; Xiao, Haihua; Yu, Chang; Liu, Jianhua; Cheng, Ziyong; Song, Haiqin; Zhang, Xinyang; Li, Chunxia; Wang, Jinqiang; Gu, Zhen; Lin, Jun

    2017-02-08

    Reactive oxygen species (ROS) plays a key role in therapeutic effects as well as side effects of platinum drugs. Cisplatin mediates activation of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX), which triggers oxygen (O2) to superoxide radical (O2•-) and its downstream H2O2. Through the Fenton's reaction, H2O2 could be catalyzed by Fe2+/Fe3+ to the toxic hydroxyl radicals (•OH), which cause oxidative damages to lipids, proteins, and DNA. By taking the full advantage of Fenton's chemistry, we herein demonstrated tumor site-specific conversion of ROS generation induced by released cisplatin and Fe2+/Fe3+ from iron-oxide nanocarriers with cisplatin(IV) prodrugs for enhanced anticancer activity but minimized systemic toxicity.

  6. Mechanism and Experimental Observability of Global Switching Between Reactive and Nonreactive Coordinates at High Total Energies.

    Science.gov (United States)

    Teramoto, Hiroshi; Toda, Mikito; Takahashi, Masahiko; Kono, Hirohiko; Komatsuzaki, Tamiki

    2015-08-28

    We present a mechanism of global reaction coordinate switching, namely, a phenomenon in which the reaction coordinate dynamically switches to another coordinate as the total energy of the system increases. The mechanism is based on global changes in the underlying phase space geometry caused by a switching of dominant unstable modes from the original reactive mode to another nonreactive mode in systems with more than 2 degrees of freedom. We demonstrate an experimental observability to detect a reaction coordinate switching in an ionization reaction of a hydrogen atom in crossed electric and magnetic fields. For this reaction, the reaction coordinate is a coordinate along which electrons escape and its switching changes the escaping direction from the direction of the electric field to that of the magnetic field and, thus, the switching can be detected experimentally by measuring the angle-resolved momentum distribution of escaping electrons.

  7. A VVER-1000 LEU and MOX assembly computational benchmark analysis using the lattice burnup code EXCEL

    Energy Technology Data Exchange (ETDEWEB)

    Thilagam, L. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India)], E-mail: thilagam@igcar.gov.in; Sunil Sunny, C. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India); Jagannathan, V. [Light Water Reactor Physics Section, Reactor Physics Design Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085 (India)], E-mail: v_jagan1952@rediffmail.com; Subbaiah, K.V. [AERB-Safety Research Institute, Kalpakkam, Tamilnadu 603 102 (India)

    2009-05-01

    Utilization of Mixed Uranium-Plutonium Oxide (MOX) fuel in VVER-1000 reactors envisages the core physics analysis using computational methods and validation of the related computer codes. Towards this objective, an international experts group has been established at OECD/NEA. The experts group facilitates sharing of existing information on physics parameters and fuel behaviour. Several benchmark exercises have been proposed by them with intent to investigate the core physics behaviour of a VVER-1000 reactor loaded with 2/3rd of low enriched uranium (LEU) fuel assemblies (FA) and 1/3rd of weapons grade mixed oxide (MOX) FA. In the present study an attempt is made to analyse 'AVVER-1000LEUandMOXAssemblyComputationalBenchmark' and predict the neutronics behaviour at the lattice level. The lattice burnup code EXCEL, developed at Light Water Reactor Physics Section, BARC is employed for this task. The EXCEL code uses the 172 energy group 'JEFF31GX' cross-section library in WIMS-D format. Assembly level fuel depletion calculations are performed up to a burnup of 40 MWD/kg of heavy metal (HM). Studies are made for the parametric variations of fuel and moderator temperatures, coolant density and boron content in the coolant. Both operational and off-normal states are analysed to determine the corresponding infinite neutron multiplication factor (k{sub {infinity}}). Pin wise isotopic compositions are computed as a function of burnup. Isotopic compositions in different annular regions of Uranium-Gadolinium (UGD) pin, fission rate distributions in UGD, UO{sub 2} and MOX pin cells are also computed. The predicted results are compared with the benchmark mean results.

  8. Criticality Analysis of Assembly Misload in a PWR Burnup Credit Cask

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, J. C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2008-01-31

    The Interim Staff Guidance on bumup credit (ISG-8) for spent fuel in storage and transportation casks, issued by the Nuclear Regulatory Commission's Spent Fuel Project Office, recommends a bumup measurement for each assembly to confirm the reactor record and compliance with the assembly bumup value used for loading acceptance. This recommendation is intended to prevent unauthorized loading (misloading) of assemblies due to inaccuracies in reactor burnup records and/or improper assembly identification, thereby ensuring that the appropriate subcritical margin is maintained. This report presents a computational criticality safety analysis of the consequences of misloading fuel assemblies in a highcapacity cask that relies on burnup credit for criticality safety. The purpose of this report is to provide a quantitative understanding of the effects of fuel misloading events on safety margins. A wide variety of fuel-misloading configurations are investigated and results are provided for informational purposes. This report does not address the likelihood of occurrence for any of the misload configurations considered. For representative, qualified bumup-enrichment combinations, with and without fission products included, misloading two assemblies that are underburned by 75% results in an increase in keff of 0.025-0.045, while misloading four assemblies that are underburned by 50% also results in an increase in keff of 0.025-0.045. For the cask and conditions considered, a reduction in bumup of 20% in all assemblies results in an increase in kff of less than 0.035. Misloading a single fresh assembly with 3, 4, or 5 wt% 235U enrichment results in an increase in keffof--0.02, 0.04, or 0.06, respectively. The report concludes with a summary of these and other important findings, as well as a discussion of relevant issues that should be considered when assessing the appropriate role of burnup measurements.

  9. Evaluation of a High-Throughput Peptide Reactivity Format Assay for Assessment of the Skin Sensitization Potential of Chemicals.

    Science.gov (United States)

    Wong, Chin Lin; Lam, Ai-Leen; Smith, Maree T; Ghassabian, Sussan

    2016-01-01

    The direct peptide reactivity assay (DPRA) is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate, and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium, and high concentrations) and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme, and non-sensitizers) with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF), cysteine- (Ac-RFAACAA), and lysine- (Ac-RFAAKAA) containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7%) and glass (47.3%) vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2, 4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further highlight

  10. Validation of depletion codes for burnup credit evaluation of LWR assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Ranta-aho, A. [Technical Research Centre of Finland VTT, POB 1000, 02044-VTT (Finland)

    2006-07-01

    This paper reports the comparison of the CASMO-4E predictions with the radiochemical assay data from assemblies irradiated in Takahama-3 PWR and Fukushima-Daini-2 BWR, and the most recently reported spent fuel data from the VVER-440 assembly irradiated in Novovoronezh 4. Some of the calculations were repeated with the ABURN burnup code, which is a combination of the MCNP4C Monte Carlo code and the ORIGEN2 depletion code. The cross section libraries applied were based on the ENDF/B-VI and the JEF-2.2 data. (authors)

  11. High-sensitivity C-reactive protein is only weakly related to cardiovascular damage after adjustment for traditional cardiovascular risk factors

    DEFF Research Database (Denmark)

    Olsen, Michael H; Christensen, Marina K; Hansen, Tine W

    2006-01-01

    The independent prognostic value of high-sensitivity C-reactive protein (hsCRP) has been questioned, and consequently we decided to investigate whether hsCRP was associated with subclinical cardiovascular (CV) damage independently of traditional CV risk factors.......The independent prognostic value of high-sensitivity C-reactive protein (hsCRP) has been questioned, and consequently we decided to investigate whether hsCRP was associated with subclinical cardiovascular (CV) damage independently of traditional CV risk factors....

  12. Intercomparison of OH and OH reactivity measurements in a high isoprene and low NO environment during the Southern Oxidant and Aerosol Study (SOAS)

    Science.gov (United States)

    Sanchez, Dianne; Jeong, Daun; Seco, Roger; Wrangham, Ian; Park, Jeong-Hoo; Brune, William H.; Koss, Abigail; Gilman, Jessica; de Gouw, Joost; Misztal, Pawel; Goldstein, Allen; Baumann, Karsten; Wennberg, Paul O.; Keutsch, Frank N.; Guenther, Alex; Kim, Saewung

    2018-02-01

    We intercompare OH and OH reactivity datasets from two different techniques, chemical ionization mass spectrometry (CIMS) and laser-induced fluorescence (LIF) in a high isoprene and low NO environment in a southeastern US forest during the Southern Oxidant and Aerosol Study (SOAS). An LIF instrument measured OH and OH reactivity at the top of a tower, a CIMS instrument measured OH at the top of the tower, and a CIMS based comparative reactivity method (CRM-CIMS) instrument deployed at the base of the tower measured OH reactivity. Averaged diel variations of OH and OH reactivity from these datasets agree within analytical uncertainty and correlations of LIF versus CIMS for OH and OH reactivity have slopes of 0.65 and 0.97, respectively. However, there are systematic differences between the measurement datasets. The CRM-CIMS measurements of OH reactivity were ∼16% lower than those by the LIF technique in the late afternoon. We speculate that it is caused by losses in the sampling line down to the CRM-CIMS instrument. On the other hand, we could not come up with a reasonable explanation for the difference in the LIF and CIMS OH datasets for early morning and late afternoon when OH is below 1 × 106 molecules cm-3. Nonetheless, results of this intercomparison exercise strengthen previous publications from the field site on OH concentrations and atmospheric reactivity.

  13. A tip-high, Ca(2+) -interdependent, reactive oxygen species gradient is associated with polarized growth in Fucus serratus zygotes.

    Science.gov (United States)

    Coelho, Susana M B; Brownlee, Colin; Bothwell, John H F

    2008-04-01

    We report the existence of a tip-high reactive oxygen species (ROS) gradient in growing Fucus serratus zygotes, using both 5-(and 6-) chloromethyl-2',7'-dichlorodihydrofluorescein and nitroblue tetrazolium staining to report ROS generation. Suppression of the ROS gradient inhibits polarized zygotic growth; conversely, exogenous ROS generation can redirect zygotic polarization following inhibition of endogenous ROS. Confocal imaging of fluo-4 dextran distributions suggests that the ROS gradient is interdependent on the tip-high [Ca(2+)](cyt) gradient which is known to be associated with polarized growth. Our data support a model in which localized production of ROS at the rhizoid tip stimulates formation of a localized tip-high [Ca(2+)](cyt) gradient. Such modulation of intracellular [Ca(2+)](cyt) signals by ROS is a common motif in many plant and algal systems and this study extends this mechanism to embryogenesis.

  14. Thermal diffusivity of homogeneous SBR MOX fuel with a burn-up of 35 MWd/kgHM

    Science.gov (United States)

    Cozzo, C.; Staicu, D.; Pagliosa, G.; Papaioannou, D.; Rondinella, V. V.; Konings, R. J. M.; Walker, C. T.; Barker, M. A.; Hervé, P.

    2010-05-01

    The effect of burn-up on the thermal conductivity of homogeneous SBR MOX fuel is investigated and compared with standard UO 2 LWR fuel. New thermal diffusivity results obtained on SBR MOX fuel with a pellet burn-up of 35 MWd/kgHM are reported. The thermal diffusivity measurements were carried out at three radial positions using a shielded "laser-flash" device and show that the thermal diffusivity increases from the pellet periphery to the centre. The fuel thermal conductivity was found to be in the same range as for UO 2 of similar burn-up. The annealing behaviour was characterized in order to identify the degradation due to the out-of-pile auto-irradiation.

  15. Thermal diffusivity of homogeneous SBR MOX fuel with a burn-up of 35 MWd/kgHM

    Energy Technology Data Exchange (ETDEWEB)

    Cozzo, C. [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Staicu, D., E-mail: dragos.staicu@ec.europa.e [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Pagliosa, G.; Papaioannou, D.; Rondinella, V.V.; Konings, R.J.M.; Walker, C.T. [European Commission, Joint Research Centre, Institute for Transuranium Element, P.O. Box 2340, D-76125 Karlsruhe (Germany); Barker, M.A. [The UK' s National Nuclear Laboratory Ltd., Central Laboratory, Sellafield, Seascale, Cumbria CA20 1PG (United Kingdom); Herve, P. [LEEE, University Paris X, 1 Chemin Desvalliere, 92410 Ville d' Avray (France)

    2010-05-31

    The effect of burn-up on the thermal conductivity of homogeneous SBR MOX fuel is investigated and compared with standard UO{sub 2} LWR fuel. New thermal diffusivity results obtained on SBR MOX fuel with a pellet burn-up of 35 MWd/kgHM are reported. The thermal diffusivity measurements were carried out at three radial positions using a shielded 'laser-flash' device and show that the thermal diffusivity increases from the pellet periphery to the centre. The fuel thermal conductivity was found to be in the same range as for UO{sub 2} of similar burn-up. The annealing behaviour was characterized in order to identify the degradation due to the out-of-pile auto-irradiation.

  16. Uncertainty Propagation Analysis for PWR Burnup Pin-Cell Benchmark by Monte Carlo Code McCARD

    Directory of Open Access Journals (Sweden)

    Ho Jin Park

    2012-01-01

    Full Text Available In the Monte Carlo (MC burnup analyses, the uncertainty of a tally estimate at a burnup step may be induced from four sources: the statistical uncertainty caused by a finite number of simulations, the nuclear covariance data, uncertainties of number densities, and cross-correlations between the nuclear data and the number densities. In this paper, the uncertainties of kinf, reaction rates, and number densities for a PWR pin-cell benchmark problem are quantified by an uncertainty propagation formulation in the MC burnup calculations. The required sensitivities of tallied parameters to the microscopic cross-sections and the number densities are estimated by the MC differential operator sampling method accompanied by the fission source perturbation. The uncertainty propagation analyses are conducted with two nuclear covariance data—ENDF/B-VII.1 and SCALE6.1/COVA libraries—and the numerical results are compared with each other.

  17. High-on-Aspirin Residual Platelet Reactivity Evaluated Using the Multiplate® Point-of-Care Device

    Directory of Open Access Journals (Sweden)

    Mărginean Alina

    2016-03-01

    Full Text Available Objective: The aim of this study was to evaluate the prevalence of aspirin non-responsiveness using whole blood multiple electrode aggregometry and to investigate the role of different clinical and laboratory variables associated with the lack of response. Methods: The present study included 116 aspirin treated patients presented with acute coronary syndromes or stroke. Response to aspirin was assessed by impedance aggregometry using arachidonic acid as agonist, in a final concentration of 0.5 mM (ASPI test. Results: In our data set 81% (n=94 were responders and 19% (n=22 non-responders showing high-on-aspirin platelet reactivity. Correlation analysis showed that the ward of admittance, low-density lipoproteins (LDL, concomitant antibiotic treatment, beta-adrenergic receptor blockers, history of myocardial infarction as well as PCI performed on Cardiology patients have different degrees of association with aspirin response. Conclusion: Concomitant treatment with beta-adrenergic receptor inhibitors, history of myocardial infarction and Cardiology ward admittance significantly increased the chance of responding to aspirin treatment whereas antibiotic therapy and low-density lipoproteins cholesterol seemed to increase the risk of high-on-aspirin residual platelet reactivity.

  18. Determination of aldehydes and ketones with high atmospheric reactivity on diesel exhaust using a biofuel from animal fats

    Science.gov (United States)

    Ballesteros, R.; Monedero, E.; Guillén-Flores, J.

    2011-05-01

    Biodiesel from animal fats appears as an alternative for conventional diesel in automotive consumption. Animal fats are classified into three categories, although only one of them can be used for biodiesel production, according to regulation. Due to its novelty, researchers testing animal-fat biodiesel on diesel engines focus only on regulated emissions. In this paper, the experiments carried out analyze carbonyl compounds emissions, due to its highly atmospheric reactivity, to complete the characterization of the total emissions in this kind of biofuel. Two fuels, a reference petro-diesel and a pure animal-fat biodiesel, were tested in a 4-cylinder, direct injection, diesel engine Nissan Euro 5 M1D-Bk. Samples were collected in 4 different operating modes and 3 points along the exhaust line. The analyses of samples were made in a high performance liquid chromatography, following the method recommended by the CARB to analyze air quality. Results show, on the one hand, a significant rise in carbonyl emissions, almost three times at the mode with highest hydrocarbon emissions, when biodiesel is used. On the other hand, on average, a reduction of 90% of carbonyl emissions when exhaust gases go through the different post-treatment systems installed. Despite this reduction, specific reactivity does not decrease substantially.

  19. Low-carbohydrate, high-protein, high-fat diet alters small peripheral artery reactivity in metabolic syndrome patients.

    Science.gov (United States)

    Merino, Jordi; Kones, Richard; Ferré, Raimon; Plana, Núria; Girona, Josefa; Aragonés, Gemma; Ibarretxe, Daiana; Heras, Mercedes; Masana, Luis

    2014-01-01

    Low carbohydrate diets have become increasingly popular for weight loss. Although they may improve some metabolic markers, particularly in type 2 diabetes mellitus (T2D) or metabolic syndrome (MS), their net effect on vascular function remains unclear. Evaluate the relation between dietary macronutrient composition and the small artery reactive hyperaemia index (saRHI), a marker of small artery vascular function, in a cohort of MS patients. This cross-sectional study included 160 MS patients. Diet was evaluated by a 3-day food-intake register and reduced to a novel low-carbohydrate diet score (LCDS). Physical examination, demographic, biochemical and anthropometry parameters were recorded, and saRHI was measured in each patient. Individuals in the lowest LCDS quartile (Q1; 45% carbohydrate, 19% protein, 31% fat) had higher saRHI values than those in the top quartile (Q4; 30% carbohydrate, 25% protein, 43% fat) (1.84±0.42 vs. 1.55±0.25, P=.012). These results were similar in T2D patients (Q1=1.779±0.311 vs. Q4=1.618±0.352, P=.011) and also in all of the MS components, except for low HDLc. Multivariate analysis demonstrated that individuals in the highest LCDS quartile, that is, consuming less carbohydrates, had a significantly negative coefficient of saRHI which was independent of confounders (HR: -0.747; 95%CI: 0.201, 0.882; P=.029). These data suggest that a dietary pattern characterized by a low amount of carbohydrate, but reciprocally higher amounts of fat and protein, is associated with poorer vascular reactivity in patients with MS and T2D. Copyright © 2013 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  20. High-Avidity and Potently Neutralizing Cross-Reactive Human Monoclonal Antibodies Derived from Secondary Dengue Virus Infection

    Science.gov (United States)

    Tsai, Wen-Yang; Lai, Chih-Yun; Wu, Yi-Chieh; Lin, Hong-En; Edwards, Carolyn; Jumnainsong, Amonrat; Kliks, Srisakul; Halstead, Scott; Mongkolsapaya, Juthathip; Screaton, Gavin R.

    2013-01-01

    The envelope (E) protein of dengue virus (DENV) is the major target of neutralizing antibodies (Abs) and vaccine development. Previous studies of human dengue-immune sera reported that a significant proportion of anti-E Abs, known as group-reactive (GR) Abs, were cross-reactive to all four DENV serotypes and to one or more other flaviviruses. Based on studies of mouse anti-E monoclonal antibodies (MAbs), GR MAbs were nonneutralizing or weakly neutralizing compared with type-specific MAbs; a GR response was thus not regarded as important for vaccine strategy. We investigated the epitopes, binding avidities, and neutralization potencies of 32 human GR anti-E MAbs. In addition to fusion loop (FL) residues in E protein domain II, human GR MAbs recognized an epitope involving both FL and bc loop residues in domain II. The neutralization potencies and binding avidities of GR MAbs derived from secondary DENV infection were stronger than those derived from primary infection. GR MAbs derived from primary DENV infection primarily blocked attachment, whereas those derived from secondary infection blocked DENV postattachment. Analysis of the repertoire of anti-E MAbs derived from patients with primary DENV infection revealed that the majority were GR, low-avidity, and weakly neutralizing MAbs, whereas those from secondary infection were primarily GR, high-avidity, and potently neutralizing MAbs. Our findings suggest that the weakly neutralizing GR anti-E Abs generated from primary DENV infection become potently neutralizing MAbs against the four serotypes after secondary infection. The observation that the dengue immune status of the host affects the quality of the cross-reactive Abs generated has implications for new strategies for DENV vaccination. PMID:24027331

  1. Application of Tin(II Chloride Catalyst for High FFA Jatropha Oil Esterification in Continuous Reactive Distillation Column

    Directory of Open Access Journals (Sweden)

    Ratna Dewi Kusumaningtyas

    2016-03-01

    Full Text Available The application of heterogeneous solid acid catalysts in biodiesel production has become popular and gained significant attention over the last few years. It is since these types of catalysts hold the benefits in terms of easy separation from the product, reusability of the catalyst, high selectivity of the reaction. They are also considered sustainable and powerful particularly in organic synthesis. This work studied the use of tin(II chloride as solid Lewis acid catalyst to promote the esterification reaction of high Free Fatty Acid (FFA jatropha oil in continuous reactive distillation column. To obtain the optimum condition, the influences of reaction time, molar ratio of the reactant, and catalyst were investigated. It was revealed that the optimum condition was achieved at the molar ratio of methanol to FFA at 1:60, catalyst concentration of 5%, and reaction temperature of 60°C with the reaction conversion of 90%. This result was significantly superior to the identical reaction performed using batch reactor. The esterification of high FFA jatropha oil using reactive distillation in the presence of tin(II chloride provided higher conversion than that of Amberlyst-15 heterogeneous catalyst and was comparable to that of homogenous sulfuric acid catalyst, which showed 30 and 94.71% conversion, respectively. The esterification reaction of high FFA jatropha oil was subsequently followed by transesterification reaction for the completion of the biodiesel production. Transesterification was carried out at 60 °C, molar ratio of methanol to oil of 1:6, NaOH catalyst of 1%, and reaction time of one hour. The jatropha biodiesel product resulted from this two steps process could satisfy the ASTM and Indonesian biodiesel standard in terms of ester content (97.79 %, density, and viscosity. Copyright © 2016 BCREC GROUP. All rights reserved Received: 10th November 2015; Revised: 4th February 2016; Accepted: 4th February 2016 How to Cite: Kusumaningtyas

  2. High C-Reactive Protein Predicts Delirium Incidence, Duration, and Feature Severity After Major Noncardiac Surgery.

    Science.gov (United States)

    Vasunilashorn, Sarinnapha M; Dillon, Simon T; Inouye, Sharon K; Ngo, Long H; Fong, Tamara G; Jones, Richard N; Travison, Thomas G; Schmitt, Eva M; Alsop, David C; Freedman, Steven D; Arnold, Steven E; Metzger, Eran D; Libermann, Towia A; Marcantonio, Edward R

    2017-08-01

    To examine associations between the inflammatory marker C-reactive protein (CRP) measured preoperatively and on postoperative day 2 (POD2) and delirium incidence, duration, and feature severity. Prospective cohort study. Two academic medical centers. Adults aged 70 and older undergoing major noncardiac surgery (N = 560). Plasma CRP was measured using enzyme-linked immunosorbent assay. Delirium was assessed from Confusion Assessment Method (CAM) interviews and chart review. Delirium duration was measured according to number of hospital days with delirium. Delirium feature severity was defined as the sum of CAM-Severity (CAM-S) scores on all postoperative hospital days. Generalized linear models were used to examine independent associations between CRP (preoperatively and POD2 separately) and delirium incidence, duration, and feature severity; prolonged hospital length of stay (LOS, >5 days); and discharge disposition. Postoperative delirium occurred in 24% of participants, 12% had 2 or more delirium days, and the mean ± standard deviation sum CAM-S was 9.3 ± 11.4. After adjusting for age, sex, surgery type, anesthesia route, medical comorbidities, and postoperative infectious complications, participants with preoperative CRP of 3 mg/L or greater had a risk of delirium that was 1.5 times as great (95% confidence interval (CI) = 1.1-2.1) as that of those with CRP less than 3 mg/L, 0.4 more delirium days (P delirium (3.6 CAM-S points higher, P delirium (95% CI = 1.0-2.4) as those in the lowest quartile (≤127.53 mg/L), had 0.2 more delirium days (P delirium (4.5 CAM-S points higher, P delirium incidence, duration, and feature severity. CRP may be useful to identify individuals who are at risk of developing delirium. © 2017, Copyright the Authors Journal compilation © 2017, The American Geriatrics Society.

  3. Does high C-reactive protein concentration increase atherosclerosis? The Whitehall II Study.

    Directory of Open Access Journals (Sweden)

    Mika Kivimäki

    Full Text Available BACKGROUND: C-reactive protein (CRP, a marker of systemic inflammation, is associated with risk of coronary events and sub-clinical measures of atherosclerosis. Evidence in support of this link being causal would include an association robust to adjustments for confounders (multivariable standard regression analysis and the association of CRP gene polymorphisms with atherosclerosis (Mendelian randomization analysis. METHODOLOGY/PRINCIPAL FINDINGS: We genotyped 3 tag single nucleotide polymorphisms (SNPs [+1444T>C (rs1130864; +2303G>A (rs1205 and +4899T>G (rs 3093077] in the CRP gene and assessed CRP and carotid intima-media thickness (CIMT, a structural marker of atherosclerosis, in 4941 men and women aged 50-74 (mean 61 years (the Whitehall II Study. The 4 major haplotypes from the SNPs were consistently associated with CRP level, but not with other risk factors that might confound the association between CRP and CIMT. CRP, assessed both at mean age 49 and at mean age 61, was associated both with CIMT in age and sex adjusted standard regression analyses and with potential confounding factors. However, the association of CRP with CIMT attenuated to the null with adjustment for confounding factors in both prospective and cross-sectional analyses. When examined using genetic variants as the instrument for serum CRP, there was no inferred association between CRP and CIMT. CONCLUSIONS/SIGNIFICANCE: Both multivariable standard regression analysis and Mendelian randomization analysis suggest that the association of CRP with carotid atheroma indexed by CIMT may not be causal.

  4. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems, t...

  5. Molecular cloning, expression and immunological characterisation of Lol p 5C, a novel allergen isoform of rye grass pollen demonstrating high IgE reactivity.

    Science.gov (United States)

    Suphioglu, C; Mawdsley, D; Schäppi, G; Gruehn, S; de Leon, M; Rolland, J M; O'Hehir, R E

    1999-12-03

    A novel isoform of a major rye grass pollen allergen Lol p 5 was isolated from a cDNA expression library. The new isoform, Lol p 5C, shares 95% amino acid sequence identity with Lol p 5A. Both isoforms demonstrated shared antigenic activity but different allergenic activities. Recombinant Lol p 5C demonstrated 100% IgE reactivity in 22 rye grass pollen sensitive patients. In comparison, recombinant Lol p 5A showed IgE reactivity in less than 64% of the patients. Therefore, Lol p 5C represents a novel and highly IgE-reactive isoform allergen of rye grass pollen.

  6. A multi-platform linking code for fuel burnup and radiotoxicity analysis

    Science.gov (United States)

    Cunha, R.; Pereira, C.; Veloso, M. A. F.; Cardoso, F.; Costa, A. L.

    2014-02-01

    A linking code between ORIGEN2.1 and MCNP has been developed at the Departamento de Engenharia Nuclear/UFMG to calculate coupled neutronic/isotopic results for nuclear systems and to produce a large number of criticality, burnup and radiotoxicity results. In its previous version, it evaluated the isotopic composition evolution in a Heat Pipe Power System model as well as the radiotoxicity and radioactivity during lifetime cycles. In the new version, the code presents features such as multi-platform execution and automatic results analysis. Improvements made in the code allow it to perform simulations in a simpler and faster way without compromising accuracy. Initially, the code generates a new input for MCNP based on the decisions of the user. After that, MCNP is run and data, such as recoverable energy per prompt fission neutron, reaction rates and keff, are automatically extracted from the output and used to calculate neutron flux and cross sections. These data are then used to construct new ORIGEN inputs, one for each cell in the core. Each new input is run on ORIGEN and generates outputs that represent the complete isotopic composition of the core on that time step. The results show good agreement between GB (Coupled Neutronic/Isotopic code) and Monteburns (Automated, Multi-Step Monte Carlo Burnup Code System), developed by the Los Alamos National Laboratory.

  7. Fuel burnup analysis for IRIS reactor using MCNPX and WIMS-D5 codes

    Science.gov (United States)

    Amin, E. A.; Bashter, I. I.; Hassan, Nabil M.; Mustafa, S. S.

    2017-02-01

    International Reactor Innovative and Secure (IRIS) reactor is a compact power reactor designed with especial features. It contains Integral Fuel Burnable Absorber (IFBA). The core is heterogeneous both axially and radially. This work provides the full core burn up analysis for IRIS reactor using MCNPX and WIMDS-D5 codes. Criticality calculations, radial and axial power distributions and nuclear peaking factor at the different stages of burnup were studied. Effective multiplication factor values for the core were estimated by coupling MCNPX code with WIMS-D5 code and compared with SAS2H/KENO-V code values at different stages of burnup. The two calculation codes show good agreement and correlation. The values of radial and axial powers for the full core were also compared with published results given by SAS2H/KENO-V code (at the beginning and end of reactor operation). The behavior of both radial and axial power distribution is quiet similar to the other data published by SAS2H/KENO-V code. The peaking factor values estimated in the present work are close to its values calculated by SAS2H/KENO-V code.

  8. Impact of CO2 injection protocol on fluid-solid reactivity: high-pressure and temperature microfluidic experiments in limestone

    Science.gov (United States)

    Jimenez-Martinez, Joaquin; Porter, Mark; Carey, James; Guthrie, George; Viswanathan, Hari

    2017-04-01

    Geological sequestration of CO2 has been proposed in the last decades as a technology to reduce greenhouse gas emissions to the atmosphere and mitigate the global climate change. However, some questions such as the impact of the protocol of CO2 injection on the fluid-solid reactivity remain open. In our experiments, two different protocols of injection are compared at the same conditions (8.4 MPa and 45 C, and constant flow rate 0.06 ml/min): i) single phase injection, i.e., CO2-saturated brine; and ii) simultaneous injection of CO2-saturated brine and scCO2. For that purpose, we combine a unique high-pressure/temperature microfluidics experimental system, which allows reproducing geological reservoir conditions in geo-material substrates (i.e., limestone, Cisco Formation, Texas, US) and high resolution optical profilometry. Single and multiphase flow through etched fracture networks were optically recorded with a microscope, while processes of dissolution-precipitation in the etched channels were quantified by comparison of the initial and final topology of the limestone micromodels. Changes in hydraulic conductivity were quantified from pressure difference along the micromodel. The simultaneous injection of CO2-saturated brine and scCO2, reduced the brine-limestone contact area and also created a highly heterogeneous velocity field (i.e., low velocities regions or stagnation zones, and high velocity regions or preferential paths), reducing rock dissolution and enhancing calcite precipitation. The results illustrate the contrasting effects of single and multiphase flow on chemical reactivity and suggest that multiphase flow by isolating parts of the flow system can enhance CO2 mineralization.

  9. A high throughput screen identifies Nefopam as targeting cell proliferation in β-catenin driven neoplastic and reactive fibroproliferative disorders.

    Directory of Open Access Journals (Sweden)

    Raymond Poon

    Full Text Available Fibroproliferative disorders include neoplastic and reactive processes (e.g. desmoid tumor and hypertrophic scars. They are characterized by activation of β-catenin signaling, and effective pharmacologic approaches are lacking. Here we undertook a high throughput screen using human desmoid tumor cell cultures to identify agents that would inhibit cell viability in tumor cells but not normal fibroblasts. Agents were then tested in additional cell cultures for an effect on cell proliferation, apoptosis, and β-catenin protein level. Ultimately they were tested in Apc1638N mice, which develop desmoid tumors, as well as in wild type mice subjected to full thickness skin wounds. The screen identified Neofopam, as an agent that inhibited cell numbers to 42% of baseline in cell cultures from β-catenin driven fibroproliferative disorders. Nefopam decreased cell proliferation and β-catenin protein level to 50% of baseline in these same cell cultures. The half maximal effective concentration in-vitro was 0.5 uM and there was a plateau in the effect after 48 hours of treatment. Nefopam caused a 45% decline in tumor number, 33% decline in tumor volume, and a 40% decline in scar size when tested in mice. There was also a 50% decline in β-catenin level in-vivo. Nefopam targets β-catenin protein level in mesenchymal cells in-vitro and in-vivo, and may be an effective therapy for neoplastic and reactive processes driven by β-catenin mediated signaling.

  10. In situ visualisation and characterisation of the capacity of highly reactive minerals to preserve soil organic matter (SOM) in colloids at submicron scale.

    Science.gov (United States)

    Xiao, Jian; Wen, Yongli; Li, Huan; Hao, Jialong; Shen, Qirong; Ran, Wei; Mei, Xinlan; He, Xinhua; Yu, Guanghui

    2015-11-01

    Mineral-organo associations (MOAs) are a mixture of identifiable biopolymers associated with highly reactive minerals and microorganisms. However, the in situ characterization and correlation between soil organic matter (SOM) and highly reactive Al and Fe minerals are still unclear for the lack of technologies, particularly in the long-term agricultural soil colloids at submicron scale. We combined several novel techniques, including nano-scale secondary ion mass spectrometry (NanoSIMS), X-ray absorption near edge structure (XANES) and confocal laser scanning microscopy (CLSM) to characterise the capacity of highly reactive Al and Fe minerals to preserve SOM in Ferralic Cambisol in south China. Our results demonstrated that: (1) highly reactive minerals were strongly related to SOM preservation, while SOM had a more significant line correlation with the highly reactive Al minerals than the highly reactive Fe minerals, according to the regions of interest correlation analyses using NanoSIMS; (2) allophane and ferrihydrite were the potential mineral species to determine the SOM preservation capability, which was evaluated by the X-ray photoelectron spectroscopy (XPS) and Fe K-edge XANES spectroscopy techniques; and (3) soil organic biopolymers with dominant compounds, such as proteins, polysaccharides and lipids, were distributed at the rough and clustered surface of MOAs with high chemical and spatial heterogeneity according to the CLSM observation. Our results also promoted the understanding of the roles played by the highly reactive Al and Fe minerals in the spatial distribution of soil organic biopolymers and SOM sequestration. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Assessment of High-Sensitivity C-Reactive Protein Levels as Diagnostic Discriminator of Maturity-Onset Diabetes of the Young Due to HNF1A Mutations

    OpenAIRE

    Owen, Katharine R.; Thanabalasingham, Gaya; James, Timothy J.; Karpe, Fredrik; Farmer, Andrew J.; McCarthy, Mark I.; Gloyn, Anna L.

    2010-01-01

    OBJECTIVE Despite the clinical importance of an accurate diagnosis in individuals with monogenic forms of diabetes, restricted access to genetic testing leaves many patients with undiagnosed diabetes. Recently, common variation near the HNF1 homeobox A (HNF1A) gene was shown to influence C-reactive protein levels in healthy adults. We hypothesized that serum levels of high-sensitivity C-reactive protein (hs-CRP) could represent a clinically useful biomarker for the identification of HNF1A mut...

  12. Reactive Programming in Java

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Reactive Programming in gaining a lot of excitement. Many libraries, tools, and frameworks are beginning to make use of reactive libraries. Besides, applications dealing with big data or high frequency data can benefit from this programming paradigm. Come to this presentation to learn about what reactive programming is, what kind of problems it solves, how it solves them. We will take an example oriented approach to learning the programming model and the abstraction.

  13. Apolipoprotein A-II Influences Apolipoprotein E-Linked Cardiovascular Disease Risk in Women with High Levels of HDL Cholesterol and C-Reactive Protein

    NARCIS (Netherlands)

    Corsetti, James P.; Bakker, Stephan J. L.; Sparks, Charles E.; Dullaart, Robin P. F.

    2012-01-01

    Background: In a previous report by our group, high levels of apolipoprotein E (apoE) were demonstrated to be associated with risk of incident cardiovascular disease in women with high levels of C-reactive protein (CRP) in the setting of both low (designated as HR1 subjects) and high (designated as

  14. DEVELOPMENT OF SULFHYDRYL-REACTIVE SILICA FOR PROTEIN IMMOBILIZATION IN HIGH-PERFORMANCE AFFINITY CHROMATOGRAPHY

    OpenAIRE

    Mallik, Rangan; Wa, Chunling; Hage, David S.

    2007-01-01

    Two techniques were developed for the immobilization of proteins and other ligands to silica through sulfhydryl groups. These methods made use of maleimide-activated silica (the SMCC method) or iodoacetyl-activated silica (the SIA method). The resulting supports were tested for use in high-performance affinity chromatography by employing human serum albumin (HSA) as a model protein. Studies with normal and iodoacetamide-modified HSA indicated that these methods had a high selectivity for sulf...

  15. Cognitive Changes during Prolonged Stay at High Altitude and Its Correlation with C-Reactive Protein.

    Directory of Open Access Journals (Sweden)

    Sheng Li Hu

    Full Text Available Hypersensitive C-reaction protein (hsCRP may be a risk factor for cognitive impairment resulting from Alzheimer's disease (AD, stroke, and vascular dementia. This study explored the correlation of peripheral blood hsCRP level with cognitive decline due to high altitude exposure. The study was conducted on 100 male military participants who had never been to high altitude. Cerebral oxygen saturation monitoring, event related potentials (P300, N200 detection, and neurocognitive assessment was performed and total hsCRP, interleukin-6 (IL-6, and homocysteine was estimated at 500 m altitude, 3650 m altitude, 3 day, 1, and 3 month post arriving at the base camp (4400 m, and 1 month after coming back to the 500 m altitude. High altitude increased brain oxygen saturation, prolonged P300 and N200 latencies, injured cognitive functions, and raised plasma hsCRP levels. But they all recovered in varying degrees at 1 and 3 month post arriving at the base camp (4400 m. P300 latencies and hsCRP levels were strongly correlated to cognitive performances. These results suggested that cognitive deterioration occurred during the acute period of exposure to high altitude and may recover probably owning to acclimatization after extended stay at high altitude. Plasma hsCRP is inversely correlated to neurological cognition and it may be a potential biomarker for the prediction of high altitude induced cognitive dysfunction.

  16. Comparison of high-sensitivity C-reactive protein and fetuin-A levels before and after treatment for subjects with subclinical hyperthyroidism.

    Science.gov (United States)

    Bilgir, Oktay; Bilgir, Ferda; Topcuoglu, Tuba; Calan, Mehmet; Calan, Ozlem

    2014-03-01

    This study was designed to show the effect of propylthiouracil treatment on sCD40L, high-sensitivity C-reactive protein, and fetuin-A levels on subjects with subclinical hyperthyroidism. After checking sCD40L, high-sensitivity C-reactive protein, and fetuin-A levels of 35 patients with subclinical hyperthyroidism, each was given 50 mg tablets of propylthiouracil three times daily. After 3 months, sCD40L, high-sensitivity C-reactive protein, and fetuin-A levels were then compared to the levels before treatment. Although high-sensitivity C-reactive protein and sCD40L levels were normal in the subclinical hyperthyroidism patients compared to the healthy controls, fetuin-A levels were statistically significantly higher (*p = 0.022). After treatment, fetuin-A levels of subclinical hyperthyroidism patients decreased statistically significantly compared to the levels before treatment (**p = 0.026). sCD40L and high-sensitivity C-reactive protein levels did not have a statistically significant difference compared to the control group and post-propylthiouracil treatment. In subclinical hyperthyroidism patients, high fetuin-A levels before propylthiouracil treatment and decreases in these levels after treatment in cases with subclinical hyperthyroidism indicated the possibility of preventing long-term cardiac complications with propylthiouracil treatment.

  17. Evaluation of a high-throughput peptide reactivity format assay for assessment of the skin sensitization potential of chemicals

    Directory of Open Access Journals (Sweden)

    Chin Lin eWong

    2016-03-01

    Full Text Available The direct peptide reactivity assay (DPRA is a validated method for in vitro assessment of the skin sensitization potential of chemicals. In the present work, we describe a peptide reactivity assay using 96-well plate format and systematically identified the optimal assay conditions for accurate and reproducible classification of chemicals with known sensitizing capacity. The aim of the research is to ensure that the analytical component of the peptide reactivity assay is robust, accurate and reproducible in accordance with criteria that are used for the validation of bioanalytical methods. Analytical performance was evaluated using quality control samples (QCs; heptapeptides at low, medium and high concentrations and incubation of control chemicals (chemicals with known sensitization capacity, weak, moderate, strong, extreme and non-sensitizers with each of three synthetic heptapeptides, viz Cor1-C420 (Ac-NKKCDLF, cysteine- (Ac-RFAACAA and lysine- (Ac-RFAAKAA containing heptapeptides. The optimal incubation temperature for all three heptapeptides was 25°C. Apparent heptapeptide depletion was affected by vial material composition. Incubation of test chemicals with Cor1-C420, showed that peptide depletion was unchanged in polypropylene vials over 3-days storage in an autosampler but this was not the case for borosilicate glass vials. For cysteine-containing heptapeptide, the concentration was not stable by day 3 post-incubation in borosilicate glass vials. Although the lysine-containing heptapeptide concentration was unchanged in both polypropylene and borosilicate glass vials, the apparent extent of lysine-containing heptapeptide depletion by ethyl acrylate, differed between polypropylene (24.7% and glass (47.3% vials. Additionally, the peptide-chemical complexes for Cor1-C420-cinnamaldehyde and cysteine-containing heptapeptide-2,4-dinitrochlorobenzene were partially reversible during 3-days of autosampler storage. These observations further

  18. Association of high-sensitivity C-reactive protein with carotid artery intima-media thickness in hypertensive older adults.

    Science.gov (United States)

    Amer, Moatassem S; Elawam, Amal E; Khater, Mohamed S; Omar, Omar H; Mabrouk, Randa A; Taha, Hend M

    2011-01-01

    Hypertension is a major traditional risk factor for atherosclerosis. Increased carotid artery intima-media thickness (IMT) is considered to be a noninvasive marker of global atherosclerotic disease. The aim of this study is to assess the association between C-reactive protein (CRP) and carotid artery IMT among hypertensive older adults. A case-control study was done on 90 adults age 60 years and older, of which 60 were hypertensive (30 males and 30 females) and 30 were matched healthy controls. Measurements included conventional cardiovascular risk factors including obesity parameters, blood pressure, lipid profiles, smoking habits, the serum concentrations of high-sensitivity CRP (hs-CRP), and the carotid artery IMT. Hypertensive patients had higher body mass index, Total cholesterol, low-density lipoprotein, and hs-CRP level (P adults rather than other traditional risk factors. Copyright © 2011 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

  19. The Non-Destructive Determination of Burn-Up by Means of the Pr{sup l44} 2.18 M Gamma Activity

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, R.S.; Blackadder, W.H.

    1965-05-15

    In recent years, gamma scanning has been used at several establishments for the determination of the burn-up profile along irradiated fuel elements, the 0.75 MeV gamma from Zr-95/Nb-95 being most often employed as the monitored radiation. Difficulties in establishing the geometry and the self-absorption of the gamma activity in the fuel have tended to prevent the application of the method to quantitative burn-up determination, which has usually been carried out by dissolution of selected portions of the fuel followed by conventional fission product separation or by uranium depletion methods. The present paper describes experiments carried out to calibrate a gamma scanner for quantitative measurements by counting the 2.18 MeV gamma activity due to Pr-144, the short-lived daughter of Ce-144 (t{sub 1/2} = 285 days) from selected pellets in several UO{sub 2} fuel specimens. Accurate burn-up values were then determined by dissolution and application of the isotopic dilution method, using stable molybdenum fission products. The elements, which were rotated about their longitudinal axes to minimize asymmetry effects, were viewed by a sodium iodide crystal and a multichannel analyser through a suitable collimator. Correction for attenuation of the gamma activity (much less than for 0.75 MeV) in the fuel elements which were of different diameters (12.6 to 15.04 mm) was made by applying relative attenuation factors and the effective geometry factor of the instrument was determined. In order to check the corrections applied, the counter factor was also calculated, for the 0.75 MeV activity from Zr-95/Nb-95 and in certain cases for the 0.66 MeV activity from Cs-137. The results obtained, demonstrate that at least over the range of diameters and cooling times used the method is suitable for quantitative determinations. Preliminary experiments to explore the possibility of using the high energy gammas (2.35, 2.65 MeV) from Rh-106 as a method for estimating the fraction of

  20. Control of Acid Generation from Pyrite Oxidation in a Highly Reactive Natural Waste: A Laboratory Case Study

    Directory of Open Access Journals (Sweden)

    Yan Zhou

    2017-05-01

    Full Text Available Laboratory kinetic leach column (KLC tests were carried out to define the conditions required to control acid generation from a highly reactive, potentially acid-forming (PAF iron ore waste rock. It was found that lime addition (0.1 wt % blended plus either blending of silicates (25 wt % K-feldspar and 25 wt % chlorite, or addition of a non-acid forming (NAF top cover containing about 10% dolomite (PAF:NAF = 5:1 wt %, when watered/flushed with lime-saturated water, greatly reduced acid generation as compared to the control KLC (PAF alone, watered/flushed with Milli-Q water, but did not result in circum-neutral pH as required for pyrite surface passivation and effective acid and metalliferous drainage (AMD mitigation. In contrast, the combined use of these treatments—blended lime and silicates with an NAF cover and watering/flushing with lime-saturated water—resulted in leachate pH of 12 (up to 24 weeks. Mass balance calculations for Ca2+ and scanning electron microscopy (SEM analyses suggest that calcite or gypsum may have formed in the NAF-amended KLCs and lime with added silicate KLC. Although the combined approach in the form trialled here may not be practical or cost-effective, control of a highly reactive natural PAF waste by pyrite surface passivation appears to be possible, and an improved treatment methodology (e.g., slightly increased lime blending without the need for further lime watering/flushing could usefully be examined in the future.

  1. Elevated erythrocyte sedimentation rate and high-sensitivity C-reactive protein in osteoarthritis of the knee: relationship with clinical findings and radiographic severity.

    Science.gov (United States)

    Hanada, Mitsuru; Takahashi, Masaaki; Furuhashi, Hiroki; Koyama, Hiroshi; Matsuyama, Yukihiro

    2016-09-01

    We assessed erythrocyte sedimentation rate and high-sensitivity C-reactive protein concentration in knee osteoarthritis and non-knee osteoarthritis. In addition, we investigated potential relationship between the levels of erythrocyte sedimentation rate and high-sensitivity C-reactive protein with clinical findings and radiographic severity. We compared erythrocyte sedimentation rate and high-sensitivity C-reactive protein concentration between 104 patients with knee osteoarthritis (knee osteoarthritis group; 25 males, 79 females; mean age, 73 y) and 50 patients without knee osteoarthritis (non-knee osteoarthritis group; 16 males, 34 females; mean age, 64 y) excluding any patients with comorbid joint osteoarthritis, rheumatoid arthritis, malignant tumours or inflammatory diseases. In the knee osteoarthritis group, we assessed whether erythrocyte sedimentation rate and high-sensitivity C-reactive protein concentration differed in clinical features and Kellgren-Lawrence (KL) grades. Erythrocyte sedimentation rate and high-sensitivity C-reactive protein were significantly higher in the knee osteoarthritis group than in the non-knee osteoarthritis group (P = 0.0013 and 0.00010, respectively). In the knee osteoarthritis group, erythrocyte sedimentation rate was significantly elevated in patients with tenderness and patellar ballottement (P = 0.032 and 0.038, respectively), and high-sensitivity C-reactive protein concentration was significantly elevated in patients with tenderness, swelling and patellar ballottement (P = 0.0042, 0.00030 and 0.019, respectively). Erythrocyte sedimentation rate in KL-I was lower than erythrocyte sedimentation rate in KL-III and -IV (P = 0.012 and 0.037, respectively). Erythrocyte sedimentation rate in KL-II did not significantly differ from erythrocyte sedimentation rate in the other groups. High-sensitivity C-reactive protein concentration was lower in grade I than in KL-II, -III and -IV (P = 0.044, 0.0085 and 0

  2. Prognostic value of high sensitive C-reactive protein in subjects with silent myocardial ischemia

    DEFF Research Database (Denmark)

    Mouridsen, Mette; Intzilakis, Theodoros; Binici, Zeynep

    2012-01-01

    . High-sensitive CRP and 48-hour ambulatory ECG monitoring were performed. The primary endpoint was the combined endpoint of death and myocardial infarction. RESULTS: The median follow-up time was 76 months. Seventy-seven subjects (11.4%) had SMI. The combined endpoint occurred in 26% of the subjects...

  3. Reducing the fuel temperature for pressure-tube supercritical-water-cooled reactors and the effect of fuel burnup

    Energy Technology Data Exchange (ETDEWEB)

    Nichita, E., E-mail: eleodor.nichita@uoit.ca; Kovaltchouk, V., E-mail: vitali.kovaltchouk@uoit.ca

    2015-12-15

    Highlights: • Typical PT-SCWR fuel uses single-region pins consisting of a homogeneous mixture of ThO{sub 2} and PuO{sub 2}. • Using two regions (central for the ThO{sub 2} and peripheral for the PuO{sub 2}) reduces the fuel temperature. • Single-region-pin melting-to-average power ratio is 2.5 at 0.0 MW d/kg and 2.3 at 40 MW d/kg. • Two-region-pin melting-to-average power ratio is 36 at 0.0 MW d/kg and 10.5 at 40 MW d/kg. • Two-region-pin performance drops with burnup due to fissile-element buildup in the ThO{sub 2} region. - Abstract: The Pressure-Tube Supercritical-Water-Cooled Reactor (PT-SCWR) is one of the concepts under investigation by the Generation IV International Forum for its promise to deliver higher thermal efficiency than nuclear reactors currently in operation. The high coolant temperature (>625 K) and high linear power density employed by the PT-SCWR cause the fuel temperature to be fairly high, leading to a reduced margin to fuel melting, thus increasing the risk of actual melting during accident scenarios. It is therefore desirable to come up with a fuel design that lowers the fuel temperature while preserving the high linear power ratio and high coolant temperature. One possible solution is to separate the fertile (ThO{sub 2}) and fissile (PuO{sub 2}) fuel materials into different radial regions in each fuel pin. Previously-reported work found that by locating the fertile material at the centre and the fissile material at the periphery of the fuel pin, the fuel centreline temperature can be reduced by ∼650 K for fresh fuel compared to the case of a homogeneous (Th–Pu)O{sub 2} mixture for the same coolant temperature and linear power density. This work provides a justification for the observed reduction in fuel centreline temperature and suggests a systematic approach to lower the fuel temperature. It also extends the analysis to the dependence of the radial temperature profile on fuel burnup. The radial temperature profile is

  4. Study and reduction of reactive fields in high frequency striplines and vias with considerations for additive manufacturing approaches to microwave electronics

    Science.gov (United States)

    Reistad, Carolyn R.

    In this work, striplines and vias for printed wiring boards (PWBs) are simulated and optimized for high-frequency applications based upon reactive field theory. Additionally, considerations for the additive manufacturing of high-frequency PWB components are presented. As versatile wireless technology advances, the demand for smaller PWBs that operate at increasingly higher frequencies rises. PWBs operating at high frequencies suffer from a phenomenon known as "reactive fields." Higher-order modes are excited as a result, causing energy loss and unwanted coupling between transmission lines. Due to the presence of these reactive fields, high-frequency PWB design and fabrication become difficult and expensive ventures. To address the PWB design concerns, models of striplines and vias were created in HFSS, an electromagnetic simulation software from ANSYS, to study the reactive fields. Analyses of the electromagnetic fields in the surrounding dielectric show that, without reactive field containment, the field strength outside of the striplines and vias is comparable to the intended transmitted signal. Conventionally, reactive fields are suppressed in PWBs by inserting ground vias where the reactive field strength is strongest. However, the number of vias required to fully suppress the reactive fields is significant, indicating that the cost and complexity to manufacture a single transmission line is likewise considerable. Furthermore, vias are difficult to create from an additive manufacturing approach, making the ground via approach even more undesirable. Two novel techniques for suppressing reactive fields are presented in this work. In the first method, perfect electric conductor (PEC) blocks are placed on both sides of the stripline ports. These PEC blocks prevent higher-order modes from existing in the model, thus reducing reactive fields without the need for a large number of ground vias. PEC blocks are also easier to manufacture than vias, making this approach

  5. Recent advances in high performance poly(lactide: From green plasticization to super-tough materials via (reactive compounding

    Directory of Open Access Journals (Sweden)

    Georgio eKfoury

    2013-12-01

    Full Text Available Due to its origin from renewable resources, its biodegradability, and recently, its industrial implementation at low costs, poly(lactide (PLA is considered as one of the most promising ecological, bio-sourced and biodegradable plastic materials to potentially and increasingly replace traditional petroleum derived polymers in many commodity and engineering applications. Beside its relatively high rigidity (high tensile strength and modulus compared with many common thermoplastics such as poly(ethylene terephthalate (PET, high impact poly(styrene (HIPS and poly(propylene (PP, PLA suffers from an inherent brittleness, which can limit its applications especially where mechanical toughness such as plastic deformation at high impact rates or elongation is required. Therefore, the curve plotting stiffness vs. impact resistance and ductility must be shifted to higher values for PLA-based materials, while being preferably fully bio-based and biodegradable upon the application.This review aims to establish a state of the art focused on the recent progresses and preferably economically viable strategies developed in the literature for significantly improve the mechanical performances of PLA. A particular attention is given to plasticization as well as to impact resistance modification of PLA in the case of (reactive blending PLA-based systems.

  6. Adiponectin, Interleukin-6 and High-sensitivity C-reactive Protein Levels in Overweight/Obese Indian children.

    Science.gov (United States)

    Jain, Vandana; Kumar, Ajay; Agarwala, Anuja; Vikram, Naval; Ramakrishnan, Lakshmy

    2017-10-15

    The aim of our study was to assess serum Adiponectin, Interleukin-6 (IL-6) and high-sensitivity C-reactive protein (hsCRP) levels and their correlation with conventional risk factors for cardiovascular disease and diabetes in overweight/obese Indian children. Body mass index (BMI), waist circumference, blood pressure, fasting serum adiponectin, IL-6, hsCRP, blood glucose, triglycerides, and total and high density lipoprotein cholesterol were measured in children aged 7-15 years with BMI >85th centile. 84 overweight/obese children (48 boys) with mean (SD) age 10.2 (1.9) years were enrolled. Mean (SD) adiponectin, hsCRP and median (IQR) IL-6 levels were 6.0 (3.1) µg/mL, 3.4 (2.4) mg/L and 12.7 (5.0-90.0) pg/mL, respectively. Low adiponectin, high hsCRP and high IL-6 were noted in 16.5%, 49.4% and 54.4% participants, respectively. Adiponectin was inversely correlated with waist circumference, and IL-6 positively with BMI and blood glucose. Inflammatory mediators, hsCRP and IL-6 were elevated in half of the overweight children. Adiponectin and IL-6 correlated well with traditional risk markers.

  7. Melting Alpine glaciers enrich high-elevation lakes with reactive nitrogen.

    Science.gov (United States)

    Saros, Jasmine E; Rose, Kevin C; Clow, David W; Stephens, Verlin C; Nurse, Andrea B; Arnett, Heather A; Stone, Jeffery R; Williamson, Craig E; Wolfe, Alexander P

    2010-07-01

    Alpine glaciers have receded substantially over the last century in many regions of the world. Resulting changes in glacial runoff not only affect the hydrological cycle, but can also alter the physical (i.e., turbidity from glacial flour) and biogeochemical properties of downstream ecosystems. Here we compare nutrient concentrations, transparency gradients, algal biomass, and fossil diatom species richness in two sets of high-elevation lakes: those fed by snowpack melt alone (SF lakes) and those fed by both glacial and snowpack meltwaters (GSF lakes). We found that nitrate (NO(3)(-)) concentrations in the GSF lakes were 1-2 orders of magnitude higher than in SF lakes. Although nitrogen (N) limitation is common in alpine lakes, algal biomass was lower in highly N-enriched GSF lakes than in the N-poor SF lakes. Contrary to expectations, GSF lakes were more transparent than SF lakes to ultraviolet and equally transparent to photosynthetically active radiation. Sediment diatom assemblages had lower taxonomic richness in the GSF lakes, a feature that has persisted over the last century. Our results demonstrate that the presence of glaciers on alpine watersheds more strongly influences NO(3)(-)concentrations in high-elevation lake ecosystems than any other geomorphic or biogeographic characteristic.

  8. High versus low level of response to alcohol: evidence of differential reactivity to emotional stimuli.

    Science.gov (United States)

    Paulus, Martin P; Schuckit, Marc A; Tapert, Susan F; Tolentino, Neil J; Matthews, Scott C; Smith, Tom L; Trim, Ryan S; Hall, Shana A; Simmons, Alan N

    2012-11-15

    The low level of response (LR) or sensitivity to alcohol is genetically influenced and predicts heavy drinking and alcohol problems. Functional magnetic resonance imaging (fMRI) studies using cognitive tasks suggest that subjects with a low-LR process cognitive information differently after placebo and alcohol than those with a high LR, but no studies have evaluated whether similar LR group differences are seen during an emotional processing task. The fMRI data were gathered from 116 nonalcoholic subjects (60 women) after oral placebo or approximately .7 mL/kg of ethanol while performing a modified emotional faces processing task. These included 58 low- and high-LR pairs matched on demography and aspects of substance use. Blood alcohol levels and task performance were similar across LR groups, but low-LR subjects consumed approximately .8 drinks more/occasion. Thirteen brain regions (mostly the middle and inferior frontal gyri, cingulate, and insula) showed significant LR group or LR × placebo/alcohol condition interactions for emotional (mostly happy) faces relative to non-face trials. Low-LR subjects generally showed decreasing blood-oxygen level-dependent response contrasts across placebo to alcohol, whereas high LR showed increasing contrasts from placebo to alcohol, even after controlling for drinking quantities and alcohol-related changes in cerebral blood flow. Thus, LR group fMRI differences are as prominent during an emotional face task as during cognitive paradigms. Low-LR individuals processed both types of information in a manner that might contribute to an impaired ability to recognize modest levels of alcohol intoxication in a range of life situations. Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  9. Multivalent, high-relaxivity MRI contrast agents using rigid cysteine-reactive gadolinium complexes.

    Science.gov (United States)

    Garimella, Praveena D; Datta, Ankona; Romanini, Dante W; Raymond, Kenneth N; Francis, Matthew B

    2011-09-21

    MRI contrast agents providing very high relaxivity values can be obtained through the attachment of multiple gadolinium(III) complexes to the interior surfaces of genome-free viral capsids. In previous studies, the contrast enhancement was predicted to depend on the rigidity of the linker attaching the MRI agents to the protein surface. To test this hypothesis, a new set of Gd-hydroxypyridonate based MRI agents was prepared and attached to genetically introduced cysteine residues through flexible and rigid linkers. Greater contrast enhancements were seen for MRI agents that were attached via rigid linkers, validating the design concept and outlining a path for future improvements of nanoscale MRI contrast agents.

  10. C-reactive protein and its relation to high blood pressure in overweight or obese children and adolescents

    Science.gov (United States)

    Noronha, Juliana Andreia F.; Medeiros, Carla Campos M.; Cardoso, Anajás da Silva; Gonzaga, Nathalia Costa; Ramos, Alessandra Teixeira; Ramos, André Luiz C.

    2013-01-01

    OBJECTIVE To investigate the association between C-reactive protein (CRP) and high blood pressure (BP) in overweight or obese children and adolescents. METHODS Cross-sectional study with 184 overweight or obese children and adolescents aged from two to 18 years old, from April, 2009 to April, 2010. The classification of nutritional status used the body mass index (BMI). Based on the Centers for Disease Control and Prevention curve, individuals were classified as: overweight (BMI between the 85th-95th percentiles), obesity (BMI between 95th-97th percentiles) and severe obesity (BMI >97th percentile). Abnormal values were considered for systolic BP (SBP) and/or diastolic (DBP) if ≥90th percentile of the BP curve recommended for children and adolescents in the V Brazilian Guidelines on Hypertension, for waist circumference (WC) if ≥90th percentile of the curve established by the National Cholesterol Education Program, and for high sensitive CRP (hs-CRP) if >3mg/dL. To evaluate the association of inadequate values of CRP and the studied groups, chi-square test and analysis of variance were applied, using the Statistical Package for the Social Sciences version 17.0 and adopting a significance level of 5%. RESULTS Among the evaluated sample, 66.3% were female, 63.5%, non-white, 64.1% had severe obesity, 78.3% had altered WC and 70.6% presented high BP. There was a significant association of CRP high levels with altered WC and BMI ≥97th percentile. In adolescents, high CRP was related to high SBP. CRP mean values were higher in individuals with elevated SBP. CONCLUSIONS Inadequate values of hs-CRP were associated with severe obesity and high SBP in the studied population. These markers can be used to identify children and adolescents at higher risk for developing atherosclerosis. PMID:24142315

  11. Association between serum levels of high sensitive C-reactive protein and inflammation activity in chronic gastritis patients.

    Science.gov (United States)

    Rahmani, Asghar; Moradkhani, Atefeh; Hafezi Ahmadi, Mohammad Reza; Jafari Heirdarlo, Ali; Abangah, Ghobad; Asadollahi, Khairollah; Sayehmiri, Kourosh

    2016-01-01

    Gastritis is an important premalignant lesion and recent studies suggested a production of inflammatory cytokine-like C-reactive protein during gastritis. This study aimed to determine any relationship between high sensitive C-reactive protein (hs-CRP) and inflammation activity among patients with gastritis. Demographic and clinical variables of participants were collected by a validated questionnaire. Using histology of the gastric mucosa, Helicobacter pylori status was investigated and serum concentrations of hs-CRP were measured among dyspeptic patients. Correlation between hs-CRP serum levels and inflammation activities was evaluated by logistic regression analysis. The relation between active inflammation and other variables was evaluated by logic link function model. Totally 239 patients (56.6% female) were analysed. The prevalence of mild, moderate and severe inflammation activities was 66.5%, 23.8% and 9.6% respectively. Mean ± SD of hs-CRP among men and women were 2.85 ± 2.84 mg/dl and 2.80 ± 4.80 mg/dl (p = 0.047) respectively. Mean ± SD of hs-CRP among patients with H. pylori infection, gland atrophy, metaplasia and dysplasia were 2.83 ± 3.80 mg/dl, 3.52 ± 5.1 mg/dl, 2.22 ± 2.3 mg/dl and 5.3 ± 5.04 mg/dl respectively. Relationship between hs-CRP and inflammation activities (p gastritis, elevated hs-CRP levels may be considered as a predictive marker of changes in gastric mucosa and a promising therapeutic target for patients with gastritis.

  12. The reactivity of high oxygen coverages on Pd(110) in catalytic CO oxidation

    Science.gov (United States)

    Ladas, S.; Imbihl, R.; Ertl, G.

    1993-01-01

    The catalytic oxidation of CO on a Pd(110) surface has been investigated in CO titration experiments and under steady-state conditions in the 10 -4 Torr range. The reaction was followed by means of video-LEED, work function and rate measurements. The titration experiments with the oxygen-saturated Pd(110) surface revealed a change in the reaction mechanism from a uniform reduction of the oxygen coverage at high temperature ( T ≈ 500 K) to a hole-eating mechanism at low temperature ( T production. This effect, which presumably is associated with the formation of subsurface oxygen, can be attributed to a lowering of the CO residence time caused by a decrease in the adsorption energy of CO and to a reduction of the CO sticking coefficient. Under steady-state conditions this inhibiting effect leads to the appearance of a hysteresis in the high rate branch of the kinetics of catalytic CO oxidation upon cyclic variation of the CO pressure.

  13. Highly sensitive Lens culinaris agglutinin-reactive α-fetoprotein: a new tool for the management of hepatocellular carcinoma.

    Science.gov (United States)

    Toyoda, Hidenori; Kumada, Takashi; Tada, Toshifumi

    2011-01-01

    The highly sensitive Lens culinaris agglutinin-reactive α-fetoprotein (hs-AFP-L3), measured using a newly developed method involving microfluidics-based separation technology, was evaluated as a new tool for the management of hepatocellular carcinoma (HCC) in clinical practice. The sensitivity and specificity of hs-AFP-L3 for the diagnosis of HCC and its ability to predict the outcome of patients with HCC were analyzed based on reported studies. Compared to AFP-L3 measured using conventional methods, the sensitivity of hs-AFP-L3 was markedly higher and the specificity was comparable. In all studies, multivariate analysis found that elevation of hs-AFP-L3 was an independent factor that affected patient survival. The use of hs-AFP-L3 improves the true positive rate of patients with HCC at diagnosis, maintaining the high specificity of AFP-L3 and its indicative value for poor prognosis. The utility of this tumor marker for prediction of the development of HCC in high-risk patients under surveillance needs to be investigated. Copyright © 2011 S. Karger AG, Basel.

  14. Low vigorous physical activity is associated with increased adrenocortical reactivity to psychosocial stress in students with high stress perceptions.

    Science.gov (United States)

    Gerber, Markus; Ludyga, Sebastian; Mücke, Manuel; Colledge, Flora; Brand, Serge; Pühse, Uwe

    2017-06-01

    The pathways by which physical activity impacts on participants' health are still not fully understood. The purpose of the present study was to go beyond existing research by combining methods from survey-based and experimental stress research, and by examining whether the potential of vigorous physical activity (VPA) to attenuate physiological and psychological stress responses is moderated by participants' subjective stress perception. The sample consisted of 42 undergraduate students (M=21.2±2.2 years, 52% women). Participants self-reported their stress and wore an accelerometer device for seven consecutive days. To examine differences in the adrenocortical, autonomic and psychological stress reactivity, salivary free cortisol, heart rate, state anxiety, mood and calmness were assessed prior to, during and after the Trier Social Stress Test (TSST). The cut-offs of the American College of Sports Medicine (ACSM) were used to distinguish between students below/above current VPA recommendations. High levels of perceived stress combined with VPA levels below the ACSM's standards (students with high stress/low VPA experienced less favourable affect throughout the entire testing session (pstudents with high stress levels. Our findings highlight that promoting VPA in young adults seems to be a promising strategy to increase physiological and psychological stress resilience. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. High-affinity RNA aptamers to C-reactive protein (CRP): newly developed pre-elution methods for aptamer selection

    Science.gov (United States)

    Orito, N.; Umekage, S.; Sato, K.; Kawauchi, S.; Tanaka, H.; Sakai, E.; Tanaka, T.; Kikuchi, Y.

    2012-03-01

    We have developed a modified SELEX (systematic evolution of ligands by exponential enrichment) method to obtain RNA aptamers with high affinity to C-reactive protein (CRP). CRP is a clinical biomarker present in plasma, the level of which increases in response to infections and noninfectious inflammation. The CRP level is also an important prognostic indicator in patients with several syndromes. At present, CRP content in blood is measured immunochemically using antibodies. To develop a more sensitive method using RNA aptamers, we have attempted to obtain high-affinity RNA aptamers to CRP. We succeeded in obtaining an RNA aptamer with high affinity to CRP using a CRP-immobilized Sepharose column and pre-elution procedure. Pre-elution is a method that removes the weak binding portion from a selected RNA population by washing for a short time with buffer containing CRP. By surface plasmon-resonance (SPR) analysis, the affinity constant of this aptamer for CRP was calculated to be KD = 2.25×10-9 (M). The secondary structure, contact sites with CRP protein, and application of this aptamer will be described.

  16. The correlation between highly sensitive C-reactive protein levels and erectile function among men with late-onset hypogonadism.

    Science.gov (United States)

    Shigehara, Kazuyoshi; Konaka, Hiroyuki; Ijima, Masashi; Nohara, Takahiro; Narimoto, Kazutaka; Izumi, Koji; Kadono, Yoshifumi; Kitagawa, Yasuhide; Mizokami, Atsushi; Namiki, Mikio

    2016-12-01

    We investigated the correlation between highly sensitive C-reactive protein (hs-CRP) levels and erectile function, and assessed the clinical role of hs-CRP levels in men with late-onset hypogonadism (LOH) syndrome. For 77 participants, we assessed Sexual Health Inventory for men (SHIM) score, Aging Male Symptoms (AMS) score and International Prostate Symptom Score (IPSS). We also evaluated free testosterone (FT), hs-CRP, total cholesterol, triglyceride levels, high density lipoprotein cholesterol, hemoglobin A1c, body mass index, waist size and blood pressure. We attempted to identify parameters correlated with SHIM score and to determine the factors affecting cardiovascular risk based on hs-CRP levels. A Spearman rank correlation test revealed that age, AMS score, IPSS and hs-CRP levels were significantly correlated with SHIM score. Age-adjusted analysis revealed that hs-CRP and IPSS were the independent factors affecting SHIM score (r= -0.304 and -0.322, respectively). Seventeen patients belonged to the moderate to high risk group for cardiovascular disease, whereas the remaining 60 belonged to the low risk group. Age, FT value and SHIM score showed significant differences between the two groups. A multivariate regression analysis demonstrated that SHIM score was an independent factor affecting cardiovascular risk (OR: 0.796; 95%CI: 0.637-0.995).

  17. Neutron transport-burnup code MCORGS and its application in fusion fission hybrid blanket conceptual research

    Science.gov (United States)

    Shi, Xue-Ming; Peng, Xian-Jue

    2016-09-01

    Fusion science and technology has made progress in the last decades. However, commercialization of fusion reactors still faces challenges relating to higher fusion energy gain, irradiation-resistant material, and tritium self-sufficiency. Fusion Fission Hybrid Reactors (FFHR) can be introduced to accelerate the early application of fusion energy. Traditionally, FFHRs have been classified as either breeders or transmuters. Both need partition of plutonium from spent fuel, which will pose nuclear proliferation risks. A conceptual design of a Fusion Fission Hybrid Reactor for Energy (FFHR-E), which can make full use of natural uranium with lower nuclear proliferation risk, is presented. The fusion core parameters are similar to those of the International Thermonuclear Experimental Reactor. An alloy of natural uranium and zirconium is adopted in the fission blanket, which is cooled by light water. In order to model blanket burnup problems, a linkage code MCORGS, which couples MCNP4B and ORIGEN-S, is developed and validated through several typical benchmarks. The average blanket energy Multiplication and Tritium Breeding Ratio can be maintained at 10 and 1.15 respectively over tens of years of continuous irradiation. If simple reprocessing without separation of plutonium from uranium is adopted every few years, FFHR-E can achieve better neutronic performance. MCORGS has also been used to analyze the ultra-deep burnup model of Laser Inertial Confinement Fusion Fission Energy (LIFE) from LLNL, and a new blanket design that uses Pb instead of Be as the neutron multiplier is proposed. In addition, MCORGS has been used to simulate the fluid transmuter model of the In-Zinerater from Sandia. A brief comparison of LIFE, In-Zinerater, and FFHR-E will be given.

  18. 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

  19. Ethanol Enhances High-Salinity Stress Tolerance by Detoxifying Reactive Oxygen Species in Arabidopsis thaliana and Rice

    Directory of Open Access Journals (Sweden)

    Huong Mai Nguyen

    2017-07-01

    Full Text Available High-salinity stress considerably affects plant growth and crop yield. Thus, developing techniques to enhance high-salinity stress tolerance in plants is important. In this study, we revealed that ethanol enhances high-salinity stress tolerance in Arabidopsis thaliana and rice. To elucidate the molecular mechanism underlying the ethanol-induced tolerance, we performed microarray analyses using A. thaliana seedlings. Our data indicated that the expression levels of 1,323 and 1,293 genes were upregulated by ethanol in the presence and absence of NaCl, respectively. The expression of reactive oxygen species (ROS signaling-related genes associated with high-salinity tolerance was upregulated by ethanol under salt stress condition. Some of these genes encode ROS scavengers and transcription factors (e.g., AtZAT10 and AtZAT12. A RT-qPCR analysis confirmed that the expression levels of AtZAT10 and AtZAT12 as well as AtAPX1 and AtAPX2, which encode cytosolic ascorbate peroxidases (APX, were higher in ethanol-treated plants than in untreated control plants, when exposure to high-salinity stress. Additionally, A. thaliana cytosolic APX activity increased by ethanol in response to salinity stress. Moreover, histochemical analyses with 3,3′-diaminobenzidine (DAB and nitro blue tetrazolium (NBT revealed that ROS accumulation was inhibited by ethanol under salt stress condition in A. thaliana and rice, in which DAB staining data was further confirmed by Hydrogen peroxide (H2O2 content. These results suggest that ethanol enhances high-salinity stress tolerance by detoxifying ROS. Our findings may have implications for improving salt-stress tolerance of agriculturally important field-grown crops.

  20. ET-1 increases reactive oxygen species following hypoxia and high-salt diet in the mouse glomerulus.

    Science.gov (United States)

    Heimlich, J B; Speed, J S; Bloom, C J; O'Connor, P M; Pollock, J S; Pollock, D M

    2015-03-01

    This study was designed to determine whether ET-1 derived from endothelial cells contributes to oxidative stress in the glomerulus of mice subjected to a high-salt diet and/or hypoxia. C57BL6/J control mice or vascular endothelial cell ET-1 knockout (VEET KO) mice were subjected to 3-h exposure to hypoxia (8% O₂) and/or 2 weeks of high-salt diet (4% NaCl) prior to metabolic cage assessment of renal function and isolation of glomeruli for the determination of reactive oxygen species (ROS). In control mice, hypoxia significantly increased urinary protein excretion during the initial 24 h, but only in animals on a high-salt diet. Hypoxia increased glomerular ET-1 mRNA expression in control, but not in vascular endothelial cell ET-1 knockout (VEET KO) mice. Under normoxic conditions, mice on a high-salt diet had approx. 150% higher glomerular ET-1 mRNA expression compared with a normal-salt diet (P salt diet administration significantly increased glomerular ROS production in flox control, but not in glomeruli isolated from VEET KO mice. In C57BL6/J mice, the ETA receptor-selective antagonist, ABT-627, significantly attenuated the increase in glomerular ROS production produced by high-salt diet. In addition, chronic infusion of C57BL6/J mice with a subpressor dose of ET-1 (osmotic pumps) significantly increased the levels of glomerular ROS that were prevented by ETA antagonist treatment. These data suggest that both hypoxia and a high-salt diet increase glomerular ROS production via endothelial-derived ET-1-ETA receptor activation and provide a potential mechanism for ET-1-induced nephropathy. © 2014 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  1. Facile synthesis of polyaniline nanotubes using reactive oxide templates for high energy density pseudocapacitors

    KAUST Repository

    Chen, Wei

    2013-01-01

    A remarkable energy density of 84 W h kg(cell) -1 and a power density of 182 kW kg(cell) -1 have been achieved for full-cell pseudocapacitors using conducting polymer nanotubes (polyaniline) as electrode materials and ionic liquid as electrolytes. The polyaniline nanotubes were synthesized by a one-step in situ chemical polymerization process utilizing MnO2 nanotubes as sacrificial templates. The polyaniline-nanotube pseudocapacitors exhibit much better electrochemical performance than the polyaniline-nanofiber pseudocapacitors in both acidic aqueous and ionic liquid electrolytes. Importantly, the incorporation of ionic liquid with polyaniline-nanotubes has drastically improved the energy storage capacity of the PAni-nanotube pseudocapacitors by a factor of ∼5 times compared to that of the PAni-nanotube pseudocapacitors in the acidic aqueous electrolyte. Furthermore, even after 10000 cycles, the PAni-nanotube pseudocapacitors in the ionic liquid electrolyte maintain sufficient high energy density and can light LEDs for several minutes, with only 30 s quick charge. © 2013 The Royal Society of Chemistry.

  2. Clinical relevance of high sensitivity C-reactive protein in cardiology

    Directory of Open Access Journals (Sweden)

    Dalia Adukauskienė

    2016-01-01

    Full Text Available Coping with cardiovascular diseases (CVD, which are of the main causes of death worldwide, has influenced investigation of high sensitivity CRP (hsCRP and its role in pathogenesis, prognosis and prevention of CVD. hsCRP can be synthesized in vascular endothelium, atherosclerotic plaques, and theory of inflammatory origin of atherosclerosis is being more widely debated, raising questions, whether higher hsCRP plasma concentration might be the cause or the consequence. Summing up controversial data from multiple studies, guidelines recommend hsCRP testing for both, primary (stratifying CVD risk groups, selecting patients for statin therapy and secondary CVD prevention (prognosis of CVD and its treatment complications, evaluation of treatment efficacy in moderate CVD risk group. hsCRP testing also has role in heart failure, atrial fibrillation, arterial hypertension, valve pathology and prognosis of coronary stent thrombosis or restenosis. Medications (the well-known and the new specific – CRP binding affecting its concentration are being investigated as well.

  3. Boiler startup under conditions of convective heating of the highly reactive coal dust

    Science.gov (United States)

    Zhuikov, A. V.; Kulagin, V. A.; Baranova, M. P.; Glushkov, D. O.

    2016-12-01

    Experimental research of conditions and characteristics of ignition of the pulverized coal (with a particle size of approximately 80 μm) of different-type brown coals (1B, 2B, and 3B) during convective heating by a heated airflow (at a temperature of 425-600°C and velocity of 1-5 m/s) is carried out. The use of low-inertia thermocouples, a high-speed video camera, and dedicated software has made it possible to determine the minimum oxidizer parameters needed for coal dust ignition, and the approximation dependences of a main characteristic of the process under study―ignition delay time―on the air temperature. Results of experimental studies provide a basis for developing an optimal scheme of the boiler startup without heavy oil, which differs from the known schemes by the relatively low energy consumption for fuel-burning initiation. By example of the BKZ 75-39FB boiler, the economic usefulness of applying the boiler startup without heavy oil is shown. This scheme can be implemented using the proposed ignition burner that functions as a part of the direct system of pulverized-fuel preparation.

  4. Removing filterable reactive phosphorus from highly coloured stormwater using constructed wetlands.

    Science.gov (United States)

    Lund, M A; Lavery, P S; Froend, R F

    2001-01-01

    A constructed wetland design, consisting of 16 repeating cells was proposed for Henley Brook (Perth, Western Australia) to optimise the removal of FRP from urban stormwater. Three replicate experimental ponds (15 x 5 m), were constructed to represent at a 1:1 scale a single cell from this design. Three 5 m zones of each pond were sampled: shallow (0.3 m) vegetated (Schoenoplectus validus) inflow and outflow zones and a deeper (1 m), V-shaped central zone. In 1998/99, inflows and outflow waters were intensively sampled and analysed for FRP and Total P. In addition, all major pools of P (plants, sediment) within the ponds, and important P removal processes (benthic flux, uptake by biofilm and S. validus) were quantified. A removal efficiency of 5% (1998) and 10% (1999) was obtained for FRP. Initial uptake was mainly in plant biomass, although the sediment became an increasingly important sink. Benthic flux experiments showed that anoxia did not cause release of P from sediments, indicating that most of the P was bound as apatite rather than associated with Fe or Mn. The highly coloured waters were believed responsible for the very low biofilm biomass recorded (<1 g x m(-2)). We have demonstrated that constructed wetlands can be effective for removing FRP immediately after construction, although their long-term removal capacity needs further research.

  5. Reactivity and burnability of cement raw materials witt high manganese content

    Directory of Open Access Journals (Sweden)

    Puertas, F.

    1988-06-01

    Full Text Available It has been verified that high manganese content in raw mixes causes alters the mineralogical composition of clinkers. New phases like 2 CaO.Mn02 and Ca2AIMnO5 are developed and C3A formation can be inhibited. Manganese is a flux similar to iron in the traditional raw mixes. The presence of manganese will modify the expressions of the lime saturation factor (LSF, silica modulus (Ms and aluminum modulus (Mf. This has as consequence an increase of the proportion of interstitial phase in the obtained clinkers.

    Se ha comprobado que contenidos elevados de manganeso en el crudo provoca una modificación significativa en la composición mineralógica del clinker. Se desarrollan las fases no tradicionales 2 CaO.Mn02 y Ca2AIMnO5 , y se puede llegar, incluso, a inhibir la formación de alumínate tricálcico. El manganeso tiene un comportamiento fundente muy similar al jugado por el hierro en los crudos tradicionales, por lo que la incorporación de óxidos de manganeso al crudo produce una alteración significativa en los módulos tradicionales (LSF, Ms y Mf. Esto tiene como consecuencia inmediata un gran incremento en la proporción de fase intersticial en los clínkeres producidos.

  6. The synthesis, characterization and reactivity of high oxidation state nickel fluorides

    Energy Technology Data Exchange (ETDEWEB)

    Chacon, L.C. [Univ. of Berkeley, CA (United States). Dept. of Chemistry]|[Lawrence Berkeley National Lab., CA (United States). Chemical Sciences Div.

    1997-12-01

    The research described in this thesis has mainly addressed the challenge of the synthesis of thermodynamically unstable nickel fluorides, which cannot be made by traditional thermal methods. A low-temperature approach towards the synthesis of such transition metal fluorides exploits the greater thermodynamic stability of high oxidation states in anions and involves the use of anhydrous hydrogen fluoride (aHF) as a solvent. The general method consists of combining an aHF soluble starting material (e.g., K{sub 2}NiF{sub 6}) with a Lewis fluoroacid (e.g., BF{sub 3}), which precipitates a neutral polymeric solid state fluoride: 2 K{sup +} + NiF{sub 6}{sup 2{minus}} + BF{sub 3} {r_arrow} NiF{sub 4} + 2 BF{sub 4}{sup {minus}} + 2 K{sup +}. At room temperature, this reaction yields a different structural phase, with composition K{sub x}NiF{sub 3} (x {approx} 0.18). This material has a pseudo-hexagonal tungsten bronze structure (H{sub 0}-K{sub x}NiF{sub 3}), and is an ionic conductor, probably due to K{sup +} ions hosted in the lattice channels. R-NiF{sub 3} is capable of fluorinating a wide range of inorganic and organic substrates. These reactions have probably shed light on the mechanism of the Simons Electrochemical Fluorination (ECF) Process, an important industrial method of fluorinating organic compounds. It has long been speculated that NiF{sub 3} plays a role in the ECF process, which uses nickel electrodes in aHF solvent. K{sub 2}NiF{sub 6} also fluorinates organic compounds in aHF, but interestingly, yields different fluorinated products. The reduction of R-NiF{sub 3} and K{sub 2}NiF{sub 6} during fluorination reactions yields NiF{sub 2}. A method has been developed to regenerate NiF{sub 6}{sup 2{minus}} from NiF{sub 2}.

  7. High Frequency Radio Observations of the Reactivated Magnetar PSR J1622-4950

    Science.gov (United States)

    Pearlman, Aaron B.; Majid, Walid A.; Prince, Thomas A.; Horiuchi, Shinji; Kocz, Jonathon; Lazio, T. J. W.; Naudet, Charles J.

    2017-07-01

    Radio emission from the magnetar PSR J1622-4950 was recently reported to have resumed (Camilo et al., ATel #10346). We have carried out Target of Opportunity (ToO) radio observations of PSR J1622-4950 at S-band (2.3 GHz) and X-band (8.4 GHz) using the 70-m diameter Deep Space Network (DSN) radio dish (DSS-43) in Canberra, Australia. We report on our single polarization mode observations of PSR J1622-4950 spanning 5 hours on 23 May 2017 starting at 16:03:32 UTC. Pulsations were detected at a period of 4.327308(1) s. We measure a mean flux density of 3.8(8)/0.41(8) mJy at S/X-band, from which we derive a spectral index of -1.7(2). We note that PSR J1622-4950's spectral behavior is now consistent with the majority of pulsars, which have a mean spectral index of -1.8(2) (Maron et al. (2000)). The result by Maron et al. (2000) is used here because they included more high frequency pulsar spectra than other studies to characterize the underlying spectral index distribution over a wide frequency range. The mean flux density at S-band has now increased by an order of magnitude compared to previous flux density measurements by Scholz et al. (2017) during the magnetar's quiescent state. Furthermore, the spectral index has steepened compared to a nearly flat spectral index from flux density measurements between 1.4 and 24 GHz prior to the disappearance of the radio emission (Levin et al. (2010); Keith et al. (2011); Levin et al. (2012); Anderson et al. (2012); Scholz et al. (2017)). We are continuing to monitor changes in PSR J1622-4950's radio spectrum at both S-band and X-band. We thank the DSN (Deep Space Network) and Canberra Deep Space Communication Complex (CDSCC) teams for scheduling these observations.

  8. A linear relationship between serum high-sensitive C-reactive protein and hemoglobin in hemodialysis patients.

    Science.gov (United States)

    Heidari, Behzad; Fazli, Muhammad Reza; Misaeid, Muhammad Ali Ghazi; Heidari, Parham; Hakimi, Niloofar; Zeraati, Abbas Ali

    2015-08-01

    Inflammatory process in hemodialysis patients involves hematopoiesis. The aim of the study was to determine the relationship between serum C-reactive protein (CRP) as a marker of inflammation with hemoglobin in patients under hemodialysis. Patients under maintenance hemodialysis for more than 3 months were studied. Serum high-sensitive CRP (hs-CRP) was measured by immunoturbidimetric method and hemoglobin High serum hs-CRP (> 5 mg/l) was found in 42 (57.5 %) and anemia in 32 (43.8 %) patients. High CRP was significantly associated with anemia OR = 20.8 (95 % CI 5.35-81, p = 0.001). After adjustment for age, dialysis duration, blood indices and serum albumin, the odds of anemia in the high CRP group remained at a significant level of 16.7 (95 % CI 3.7-75, p = 0.001). Hemoglobin levels conversely correlated with serum hs-CRP (r = -0.607, r (2) = 0.36, p = 0.001). In linear regression analysis for each 1 mg/l increase in serum hs-CRP, hemoglobin value increased by 12.4 % (p = 0.002). Serum iron at cutoff level of 54 µg/dl discriminated patients with and without iron deficiency anemia with sensitivity of 93.3 %, specificity of 84 % and accuracy of 90 % (AUC ± SE = 0.901 ± 0.04 (95 % CI, 0.805-0.998, p = 0.001). These findings indicate that in hemodialysis patients, the inflammatory process alters hemoglobin level in converse correlation with CRP concentration with a linear relationship pattern. Serum iron high accuracy.

  9. BiVO{sub 4} photoanodes for water splitting with high injection efficiency, deposited by reactive magnetron co-sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Gong, Haibo [Department of Material Science and Engineering, Jinan University, Jiwei Road 106, 250022 Jinan, Shandong Province (China); Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Freudenberg, Norman; Nie, Man; Krol, Roel van de; Ellmer, Klaus, E-mail: ellmer@helmholtz-berlin.de [Institute for Solar Fuels, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

    2016-04-15

    Photoactive bismuth vanadate (BiVO{sub 4}) thin films were deposited by reactive co-magnetron sputtering from metallic Bi and V targets. The effects of the V-to-Bi ratio, molybdenum doping and post-annealing on the crystallographic and photoelectrochemical (PEC) properties of the BiVO{sub 4} films were investigated. Phase-pure monoclinic BiVO{sub 4} films, which are more photoactive than the tetragonal BiVO{sub 4} phase, were obtained under slightly vanadium-rich conditions. After annealing of the Mo-doped BiVO{sub 4} films, the photocurrent increased 2.6 times compared to undoped films. After optimization of the BiVO{sub 4} film thickness, the photocurrent densities (without a catalyst or a blocking layer or a hole scavenger) exceeded 1.2 mA/cm{sup 2} at a potential of 1.23 V{sub RHE} under solar AM1.5 irradiation. The surprisingly high injection efficiency of holes into the electrolyte is attributed to the highly porous film morphology. This co-magnetron sputtering preparation route for photoactive BiVO{sub 4} films opens new possibilities for the fabrication of large-scale devices for water splitting.

  10. BiVO4 photoanodes for water splitting with high injection efficiency, deposited by reactive magnetron co-sputtering

    Directory of Open Access Journals (Sweden)

    Haibo Gong

    2016-04-01

    Full Text Available Photoactive bismuth vanadate (BiVO4 thin films were deposited by reactive co-magnetron sputtering from metallic Bi and V targets. The effects of the V-to-Bi ratio, molybdenum doping and post-annealing on the crystallographic and photoelectrochemical (PEC properties of the BiVO4 films were investigated. Phase-pure monoclinic BiVO4 films, which are more photoactive than the tetragonal BiVO4 phase, were obtained under slightly vanadium-rich conditions. After annealing of the Mo-doped BiVO4 films, the photocurrent increased 2.6 times compared to undoped films. After optimization of the BiVO4 film thickness, the photocurrent densities (without a catalyst or a blocking layer or a hole scavenger exceeded 1.2 mA/cm2 at a potential of 1.23 VRHE under solar AM1.5 irradiation. The surprisingly high injection efficiency of holes into the electrolyte is attributed to the highly porous film morphology. This co-magnetron sputtering preparation route for photoactive BiVO4 films opens new possibilities for the fabrication of large-scale devices for water splitting.

  11. Aluminium castings with high particle volume fraction by reactive infiltration; Hanno yoshin ni yoru kotaisekiritsu no ryushi fukugo aluminium imono

    Energy Technology Data Exchange (ETDEWEB)

    Tsujikawa, M.; Ayukawa, S.; Kawamoto, M. [University of Osaka Prefecture, Osaka (Japan). Faculty of Engineering; Hino, M. [Okayama Prefectural Industrial Technology Center, Okayama (Japan)

    1998-03-25

    Study was made on reactive infiltration for improving a wear resistance by forming a high-density Al2O3 layer on Al alloy surface. Heating of a mixture of SiO2 and Al over activation energy produces Al2O3 and Si by thermit type exothermic reaction. In experiment, a proper mixture of Al powder of 10{mu}m in mean size and 99.9% in purity, and amorphous SiO2 particles of 150{mu}m in mean size was used together with zinc stearate of 2mass%. A green compact of 10mm diameter and 12mm high was prepared by compressing the above mixed powder, and placed at a position in a mold corresponding to concerned casting surface. Molten Al-12%Si alloy was poured into the mold at a proper temperature after preheating, and held in a furnace at a fixed temperature before air cooling. Al casting with Al2O3 particles of net 44vol% in its surface layer was thus obtained by using the compact of 70vol%SiO2 particles. Compressed thermit powder of 50vol%SiO2 could reduce a porosity to 6.2% under the atmospheric pressure. The dispersion tendency of fine Al2O3 particles was observed by holding molten alloy. 8 refs., 9 figs.

  12. Mechanistic basis for high reactivity of (salen)Co-OTs in the hydrolytic kinetic resolution of terminal epoxides.

    Science.gov (United States)

    Nielsen, Lars P C; Zuend, Stephan J; Ford, David D; Jacobsen, Eric N

    2012-03-02

    The (salen)Co(III)-catalyzed hydrolytic kinetic resolution (HKR) of terminal epoxides is a bimetallic process with a rate controlled by partitioning between a nucleophilic (salen)Co-OH catalyst and a Lewis acidic (salen)Co-X catalyst. The commonly used (salen)Co-OAc and (salen)Co-Cl precatalysts undergo complete and irreversible counterion addition to epoxide during the course of the epoxide hydrolysis reaction, resulting in quantitative formation of weakly Lewis acidic (salen)Co-OH and severely diminished reaction rates in the late stages of HKR reactions. In contrast, (salen)Co-OTs maintains high reactivity over the entire course of HKR reactions. We describe here an investigation of catalyst partitioning with different (salen)Co-X precatalysts and demonstrate that counterion addition to epoxide is reversible in the case of the (salen)Co-OTs. This reversible counterion addition results in stable partitioning between nucleophilic and Lewis acidic catalyst species, allowing highly efficient catalysis throughout the course of the HKR reaction.

  13. Signs of reactive attachment disorder and disinhibited social engagement disorder at age 12 years: Effects of institutional care history and high-quality foster care.

    Science.gov (United States)

    Humphreys, Kathryn L; Nelson, Charles A; Fox, Nathan A; Zeanah, Charles H

    2017-05-01

    Two disorders of attachment have been consistently identified in some young children following severe deprivation in early life: reactive attachment disorder and disinhibited social engagement disorder. However, less is known about whether signs of these disorders persist into adolescence. We examined signs of reactive attachment disorder and disinhibited social engagement disorder at age 12 years in 111 children who were abandoned at or shortly after birth and subsequently randomized to care as usual or to high-quality foster care, as well as in 50 comparison children who were never institutionalized. Consistent with expectations, those who experienced institutional care in early life had more signs of reactive attachment disorder and disinhibited social engagement disorder at age 12 years than children never institutionalized. In addition, using a conservative intent-to-treat approach, those children randomized to foster care had significantly fewer signs of reactive attachment disorder and disinhibited social engagement disorder than those randomized to care as usual. Analyses within the ever institutionalized group revealed no effects of the age of placement into foster care, but number of caregiving disruptions experienced and the percentage of the child's life spent in institutional care were significant predictors of signs of attachment disorders assessed in early adolescence. These findings indicate that adverse caregiving environments in early life have enduring effects on signs of attachment disorders, and provide further evidence that high-quality caregiving interventions are associated with reductions in both reactive attachment disorder and disinhibited social engagement disorder.

  14. Prevention of joint destruction in patients with high disease activity or high C-reactive protein levels: Post hoc analysis of the GO-FORTH study.

    Science.gov (United States)

    Tanaka, Yoshiya; Harigai, Masayoshi; Takeuchi, Tsutomu; Yamanaka, Hisashi; Ishiguro, Naoki; Yamamoto, Kazuhiko; Ishii, Yutaka; Nakajima, Hiroshi; Baker, Daniel; Miyasaka, Nobuyuki; Koike, Takao

    2016-01-01

    To assess the influence of golimumab dosage and disease activity on joint destruction in patients with active rheumatoid arthritis (RA) in the GO-FORTH study. Efficacy was compared among groups given basal methotrexate plus placebo, golimumab (50 mg), or golimumab (100 mg) with stratification by high (HDA) or moderate (MDA) baseline disease activity and by high or low baseline C-reactive protein (CRP). Among HDA or high CRP patients, the mean change of the total Sharp score was 3.48 and 3.41 in the placebo group, 1.94 and 2.71 in the 50 mg group, and 0.39 and 1.15 in the 100 mg group, respectively. The percentage of progression-free patients with HDA or high CRP was 40.4% and 40.0%, 43.1% and 38.2%, and 69.8% and 61.5%, respectively. Among MDA or low CRP patients, both golimumab doses showed similar prevention of joint destruction. Among HDA or high CRP patients, a shorter disease duration and higher TSS/disease duration ratio were associated with joint destruction. Both doses of golimumab (50 or 100 mg) prevented joint destruction in MDA or low CRP patients, but 100 mg was better for HDA or high CRP patients with a shorter disease duration or higher TSS/disease duration ratio.

  15. High sensitivity C-reactive protein levels in Acute Ischemic Stroke and subtypes: A study from a tertiary care center.

    Science.gov (United States)

    Chaudhuri, Jaydip Ray; Mridula, Kandadai Rukmini; Umamahesh, Matapathi; Swathi, Alluri; Balaraju, Banda; Bandaru, Venkata Chandrasekher Srinivasarao

    2013-01-01

    Stroke is a heterogeneous disease with several risk factors. High sensitivity C-reactive protein (hsCRP) is a marker for cardiovascular and cerebrovascular diseases. Recent studies have shown that high hsCRP level is a risk factor for ischemic stroke. The objective of our study was to investigate the association of high hsCRP (> 3 mg/L) levels with ischemic stroke and its subtypes in Indian patients. We recruited 210 consecutive acute stroke patients and 150 age and sex matched controls. Stroke patients were admitted within 72 hours of onset, at Yashoda Hospital, Hyderabad, India. The study period was from January 2011 to December 2012. All patients underwent tests as per standard protocol for stroke workup. Serum hsCRP level was assessed in all stroke patients and controls on the day of admission. The mean hsCRP was significantly higher in stroke patients (3.8 ± 2.5) than controls (1.8 ± 1.5) (P < 0.001). High hsCRP had higher frequency in stroke patients 130 (61.9%) compared to controls 10 (6.6%), P < 0.001. High hsCRP level was more prevalent in the stroke subtypes of cardioembolic stroke (83.3%) and large artery atherosclerosis (72%). High hsCRP level was significantly associated with hypercholesterolemia (P = 0.001), age (P = 0.01), and mortality (0.04). After adjustment of regression analysis it was observed that high level hsCRP is independently associated with acute ischemic stroke (Odds 4.5; 95% CI: 2.5-12.2); especially the stroke subtypes of cardioembolic stroke, (odds ratio 3.4, 95% CI: 1.9-10.5) and large artery atherosclerosis (odds ratio 2.1, 95% CI: 1.5-3.8). High hsCRP level is strongly associated with and an independent predictor of acute ischemic stroke. The association was found in all ischemic stroke subtypes.

  16. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses-Isotopic Composition Predictions

    Energy Technology Data Exchange (ETDEWEB)

    Radulescu, Georgeta [ORNL; Gauld, Ian C [ORNL; Ilas, Germina [ORNL; Wagner, John C [ORNL

    2011-01-01

    The expanded use of burnup credit in the United States (U.S.) for storage and transport casks, particularly in the acceptance of credit for fission products, has been constrained by the availability of experimental fission product data to support code validation. The U.S. Nuclear Regulatory Commission (NRC) staff has noted that the rationale for restricting the Interim Staff Guidance on burnup credit for storage and transportation casks (ISG-8) to actinide-only is based largely on the lack of clear, definitive experiments that can be used to estimate the bias and uncertainty for computational analyses associated with using burnup credit. To address the issues of burnup credit criticality validation, the NRC initiated a project with the Oak Ridge National Laboratory to (1) develop and establish a technically sound validation approach for commercial spent nuclear fuel (SNF) criticality safety evaluations based on best-available data and methods and (2) apply the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The purpose of this paper is to describe the isotopic composition (depletion) validation approach and resulting observations and recommendations. Validation of the criticality calculations is addressed in a companion paper at this conference. For isotopic composition validation, the approach is to determine burnup-dependent bias and uncertainty in the effective neutron multiplication factor (keff) due to bias and uncertainty in isotopic predictions, via comparisons of isotopic composition predictions (calculated) and measured isotopic compositions from destructive radiochemical assay utilizing as much assay data as is available, and a best-estimate Monte Carlo based method. This paper (1) provides a detailed description of the burnup credit isotopic validation approach and its technical bases, (2) describes the application of the approach for

  17. [Reactive arthritis].

    Science.gov (United States)

    Gerloni, V; Fantini, F

    1990-01-01

    The term reactive arthritis was introduced to describe an acute non-purulent arthritis complicating an infection elsewhere in the body. Reactive arthritis can also be classified into HLA-B27 associated and non-associated forms. Rheumatic fever is an example of the HLA-B27 non-associated forms with genetic factors other than HLA-B27 involved. HLA-B27 associated reactive arthritis includes enteric, urogenic and idiopathic arthritides. The bacteria known to trigger post-enteritic reactive arthritis are: Yersinia, Salmonella, Shigella, Campylobacter, Clostridium difficile and Brucella; those known to trigger post-urethritic reactive arthritis are Chlamydia trachomatis and Ureaplasma urealyticum, but often the germ remains unidentified. Mechanisms through which susceptibility to reactive arthritis is linked to HLA-B27 antigen are still incompletely understood, but a clue could be cross-reactivity between B27 and a surface antigen of pathogenic germs. The clinical profile of the disease is characterized by an asymmetrical oligoarthritis with involvement particularly of the peripheral joints of the lower limbs. The arthritis generally recovers without sequelae within a few weeks or months. Accompanying features can be the involvement of enthesis and tendon sheets in form of a talalgia or dactylitis. In some cases the arthritis can relapse and chronicize. In some cases, in addition, involvement of the axial skeleton can occur (spondylitis and/or sacroiliitis). Another feature of the disease is the frequent association with typical extra-articular manifestations such as uveitis and muco-cutaneous lesions.

  18. Association of high-sensitivity C-reactive protein and uric acid with the metabolic syndrome components.

    Science.gov (United States)

    Sah, Santosh Kumar; Khatiwada, Saroj; Pandey, Sunil; Kc, Rajendra; Das, Binod Kumar Lal; Baral, Nirmal; Lamsal, Madhab

    2016-01-01

    Metabolic syndrome (MetS) has been found to be associated with inflammatory molecules. This study was conducted among 125 MetS patients at B P Koirala Institute of Health Sciences, Dharan, Nepal to find an association of high-sensitivity C-reactive protein (hs-CRP) and serum uric acid with MetS components. Anthropometric measurements, blood pressure, medical history and blood samples were taken. Estimation of hs-CRP, serum uric acid, blood glucose, triglyceride and high density lipoprotein (HDL) cholesterol was done. hs-CRP had positive correlation with blood glucose (r = 0.2, p = 0.026) and negative with HDL cholesterol (r = -0.361, p uric acid had positive correlation with waist circumference (r = 0.178, p = 0.047). Patients with elevated hs-CRP and uric acid had higher waist circumference (p = 0.03), diastolic BP (p = 0.002) and lower HDL cholesterol (p = 0.004) than others. Elevated hs-CRP and high uric acid were individually associated with higher odds for low HDL cholesterol (7.992; 1.785-35.774, p = 0.002) and hyperglycemia (2.471; 1.111-5.495, p = 0.029) respectively. Combined rise of hs-CRP and uric acid was associated with severity of MetS (p uric acid. The present study demonstrates that hs-CRP and serum uric acid are associated with MetS components, and the combined rise of hs-CRP and uric acid is associated with the increase in severity of MetS.

  19. Development and applications of methodologies for the neutronic design of the Pebble Bed Advanced High Temperature Reactor (PB-AHTR)

    Science.gov (United States)

    Fratoni, Massimiliano

    This study investigated the neutronic characteristics of the Pebble Bed Advanced High Temperature Reactor (PB-AHTR), a novel nuclear reactor concept that combines liquid salt (7LiF-BeF2---flibe) cooling and TRISO coated-particle fuel technology. The use of flibe enables operation at high power density and atmospheric pressure and improves passive decay-heat removal capabilities, but flibe, unlike conventional helium coolant, is not transparent to neutrons. The flibe occupies 40% of the PB-AHTR core volume and absorbs ˜8% of the neutrons, but also acts as an effective neutron moderator. Two novel methodologies were developed for calculating the time dependent and equilibrium core composition: (1) a simplified single pebble model that is relatively fast; (2) a full 3D core model that is accurate and flexible but computationally intensive. A parametric analysis was performed spanning a wide range of fuel kernel diameters and graphite-to-heavy metal atom ratios to determine the attainable burnup and reactivity coefficients. Using 10% enriched uranium ˜130 GWd/tHM burnup was found to be attainable, when the graphite-to-heavy metal atom ratio (C/HM) is in the range of 300 to 400. At this or smaller C/HM ratio all reactivity coefficients examined---coolant temperature, coolant small and full void, fuel temperature, and moderator temperature, were found to be negative. The PB-AHTR performance was compared to that of alternative options for HTRs, including the helium-cooled pebble-bed reactor and prismatic fuel reactors, both gas-cooled and flibe-cooled. The attainable burnup of all designs was found to be similar. The PB-AHTR generates at least 30% more energy per pebble than the He-cooled pebble-bed reactor. Compared to LWRs the PB-AHTR requires 30% less natural uranium and 20% less separative work per unit of electricity generated. For deep burn TRU fuel made from recycled LWR spent fuel, it was found that in a single pass through the core ˜66% of the TRU can be

  20. Investigation of High-Sensitivity C-reactive Protein and Erythrocyte Sedimentation Rate in Low Back Pain Patients

    Science.gov (United States)

    Lee, Sang Ho

    2010-01-01

    Background Chronic low back pain can be a manifestation of lumbar degenerative disease, herniation of intervertebral discs, arthritis, or lumbar stenosis. When nerve roots are compromised, low back pain, with or without lower extremity involvement, may occur. Local inflammatory processes play an important role in patients with acute lumbosciatic pain. The purpose of this study was to assess the value of erythrocyte sedimentation rate (ESR) and high sensitivity C-reactive protein (hsCRP) measurements in patients with chronic low back pain or radiculopathy. Methods ESR and hsCRP were measured in 273 blood samples from male and female subjects with low back pain and/or radiculopathy due to herniated lumbar disc, spinal stenosis, facet syndrome, and other diseases. The hsCRP and ESR were measured prior to lumbar epidural steroid injection. Results The mean ESR was 18.8 mm/h and mean hsCRP was 1.1 mg/L. ESR had a correlation with age. Conclusions A significant systemic inflammatory reaction did not appear to arise in patients with chronic low back pain. PMID:20556218

  1. High-sensitivity C-reactive protein and exercise-induced changes in subjects suspected of coronary artery disease

    DEFF Research Database (Denmark)

    Mouridsen, Mette Rauhe; Nielsen, Olav Wendelboe; Carlsen, Christian Malchau

    2014-01-01

    BACKGROUND: Inflammation plays a major role in the development of atherosclerosis. We wanted to investigate the effects of exercise on high-sensitivity (hs) C-reactive protein (CRP) in subjects who were suspected of having coronary artery disease (CAD). METHODS: Blood samples were obtained before......, 5 minutes after, and 20 hours after an exercise test in 155 subjects who were suspected of CAD. Coronary anatomy was evaluated by computed tomography coronary angiography and/or coronary angiography. RESULTS: Median baseline hs-CRP was higher in subjects with ≥50% coronary artery lumen diameter...... stenosis (n=41), compared with non-CAD-subjects (n=114), 2.93 mg/L (interquartile range 1.03-5.06 mg/L) and 1.30 mg/L (interquartile range 0.76-2.74 mg/L), respectively, P=0.007. In multivariate analyses testing conventional risk factors, hs-CRP proved borderline significant, odds ratio =2.32, P=0...

  2. HIF-independent regulation of thioredoxin reductase 1 contributes to the high levels of reactive oxygen species induced by hypoxia.

    Directory of Open Access Journals (Sweden)

    Salvador Naranjo-Suarez

    Full Text Available Cellular adaptation to hypoxic conditions mainly involves transcriptional changes in which hypoxia inducible factors (HIFs play a critical role. Under hypoxic conditions, HIF protein is stabilized due to inhibition of the activity of prolyl hydroxylases (EGLNs. Because the reaction carried out by these enzymes uses oxygen as a co-substrate it is generally accepted that the hypoxic inhibition of EGLNs is due to the reduction in oxygen levels. However, several studies have reported that hypoxic generation of mitochondrial reactive oxygen species (ROS is required for HIF stabilization. Here, we show that hypoxia downregulates thioredoxin reductase 1 (TR1 mRNA and protein levels. This hypoxic TR1 regulation is HIF independent, as HIF stabilization by EGLNs inhibitors does not affect TR1 expression and HIF deficiency does not block TR1 hypoxic-regulation, and it has an effect on TR1 function, as hypoxic conditions also reduce TR1 activity. We found that, when cultured under hypoxic conditions, TR1 deficient cells showed a larger accumulation of ROS compared to control cells, whereas TR1 over-expression was able to block the hypoxic generation of ROS. Furthermore, the changes in ROS levels observed in TR1 deficient or TR1 over-expressing cells did not affect HIF stabilization or function. These results indicate that hypoxic TR1 down-regulation is important in maintaining high levels of ROS under hypoxic conditions and that HIF stabilization and activity do not require hypoxic generation of ROS.

  3. Traffic exposure in a population with high prevalence type 2 diabetes - Do medications influence concentrations of C-reactive protein?

    Energy Technology Data Exchange (ETDEWEB)

    Rioux, Christine L., E-mail: christine.rioux@tufts.edu [Department of Public Health and Community Medicine, Tufts University, 136 Harrison Avenue, Boston, MA 02111 (United States); Tucker, Katherine L. [Department of Health Science, Northeastern University, Boston, MA (United States); Brugge, Doug [Department of Public Health and Community Medicine, Tufts University, 136 Harrison Avenue, Boston, MA 02111 (United States); Gute, David M. [Department of Civil and Environmental Engineering, Tufts University, Medford, MA (United States); Mwamburi, Mkaya [Department of Public Health and Community Medicine, Tufts University, 136 Harrison Avenue, Boston, MA 02111 (United States)

    2011-08-15

    Type 2 Diabetes (T2D) and particulate air pollution are associated with inflammatory dysregulation. We assessed the modifying effects of diabetes medications on the association of C-reactive protein (CRP), a marker of inflammation, and traffic exposure in adults with T2D (n = 379). CRP concentrations were significantly positively associated with residence {<=}100 m of a roadway, >100 m and {<=}200 m of a roadway and increased traffic density for individuals using insulin. For individuals using oral hypoglycemic medications (OHAs), CRP was significantly negatively associated with residence >100 m - {<=}200 m of a roadway and multiple roadway exposure in an interaction model. Among people with diabetes, individuals on insulin appear to be most vulnerable to the effects of traffic exposure. Disease severity among insulin users may promote the pro-inflammatory response to traffic exposure, though diabetes medications may also modify the response. Possible anti-inflammatory effects of OHAs with traffic exposure merit further evaluation. - Highlights: >We examine traffic exposure in a population with high rates of Type 2 Diabetes. >Differences in CRP were evaluated by traffic levels, medication use and type. >Those on insulin had significantly higher CRP with traffic exposure. >Interaction models demonstrated lower CRP with traffic exposure and OHA use. >Diabetes medications may modify the response to traffic exposure. - Among people with diabetes, individuals on insulin appear to be most vulnerable to the effects of traffic exposure. Diabetes medications may modify the response to traffic.

  4. High sensitivity C-reactive protein distribution in the elderly: the Bambuí Cohort Study, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Assunção, L.G.S. [Programa de Pós-Graduação em Patologia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Eloi-Santos, S.M. [Programa de Pós-Graduação em Patologia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Departamento de Propedêutica Complementar, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Peixoto, S.V. [Departamento de Enfermagem Aplicada, Escola de Enfermagem, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG (Brazil); Lima-Costa, M.F. [Departamento de Medicina Preventiva e Social, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Centro de Pesquisas René Rachou, Fundação Oswaldo Cruz, Belo Horizonte, MG (Brazil); Vidigal, P.G. [Programa de Pós-Graduação em Patologia, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Departamento de Propedêutica Complementar, Faculdade de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2012-09-28

    The measurement of the serum concentration of the acute-phase reactant C-reactive protein (CRP) provides a useful marker in clinical practice. However, the distribution of CRP is not available for all age and population groups. This study assessed the distribution of high sensitivity CRP (hs-CRP) by gender and age in 1470 elderly individuals from a Brazilian community that participates in the Bambuí Cohort Study. Blood samples were collected after 12 h of fasting and serum samples were stored at -70°C. Measurements were made with a commercial hs-CRP immunonephelometric instrument. More than 50% of the results were above 3.0 mg/L for both genders. Mean hs-CRP was higher in women (3.62 ± 2.58 mg/L) than in men (3.03 ± 2.50 mg/L). This difference was observed for all ages, except for the over-80 age group. This is the first population-based study to describe hs-CRP values in Latin American elderly subjects. Our results indicate that significant gender differences exist in the distribution of hs-CRP, and suggest that gender-specific cut-off points for hs-CRP would be necessary for the prediction of cardiovascular risks.

  5. High sensitivity C-reactive protein distribution in the elderly: the Bambuí Cohort Study, Brazil

    Directory of Open Access Journals (Sweden)

    L.G.S. Assunção

    2012-12-01

    Full Text Available The measurement of the serum concentration of the acute-phase reactant C-reactive protein (CRP provides a useful marker in clinical practice. However, the distribution of CRP is not available for all age and population groups. This study assessed the distribution of high sensitivity-CRP (hs-CRP by gender and age in 1470 elderly individuals from a Brazilian community that participates in the Bambuí Cohort Study. Blood samples were collected after 12 h of fasting and serum samples were stored at -70°C. Measurements were made with a commercial hs-CRP immunonephelometric instrument. More than 50% of the results were above 3.0 mg/L for both genders. Mean hs-CRP was higher in women (3.62 ± 2.58 mg/L than in men (3.03 ± 2.50 mg/L. This difference was observed for all ages, except for the over-80 age group. This is the first population-based study to describe hs-CRP values in Latin American elderly subjects. Our results indicate that significant gender differences exist in the distribution of hs-CRP, and suggest that gender-specific cut-off points for hs-CRP would be necessary for the prediction of cardiovascular risks.

  6. Photolytic generation of benzhydryl cations and radicals from quaternary phosphonium salts: how highly reactive carbocations survive their first nanoseconds.

    Science.gov (United States)

    Ammer, Johannes; Sailer, Christian F; Riedle, Eberhard; Mayr, Herbert

    2012-07-18

    UV irradiation (266 or 280 nm) of benzhydryl triarylphosphonium salts Ar(2)CH-PAr(3)(+)X(-) yields benzhydryl cations Ar(2)CH(+) and/or benzhydryl radicals Ar(2)CH(•). The efficiency and mechanism of the photo-cleavage were studied by nanosecond laser flash photolysis and by ultrafast spectroscopy with a state-of-the-art femtosecond transient spectrometer. The influences of the photo-electrofuge (Ar(2)CH(+)), the photo-nucleofuge (PPh(3) or P(p-Cl-C(6)H(4))(3)), the counterion (X(-) = BF(4)(-), SbF(6)(-), Cl(-), or Br(-)), and the solvent (CH(2)Cl(2) or CH(3)CN) were investigated. Photogeneration of carbocations from Ar(2)CH-PAr(3)(+)BF(4)(-) or -SbF(6)(-) is considerably more efficient than from typical neutral precursors (e.g., benzhydryl chlorides or bromides). The photochemistry of phosphonium salts is controlled by the degree of ion pairing, which depends on the solvent and the concentration of the phosphonium salts. High yields of carbocations are obtained by photolyses of phosphonium salts with complex counterions (X(-) = BF(4)(-) or SbF(6)(-)), while photolyses of phosphonium halides Ar(2)CH-PPh(3)(+)X(-) (X(-) = Cl(-) or Br(-)) in CH(2)Cl(2) yield benzhydryl radicals Ar(2)CH(•) due to photo-electron transfer in the excited phosphonium halide ion pair. At low concentrations in CH(3)CN, the precursor salts are mostly unpaired, and the photo-cleavage mechanism is independent of the nature of the counter-anions. Dichloromethane is better suited for generating the more reactive benzhydryl cations than the more polar and more nucleophilic solvents CH(3)CN or CF(3)CH(2)OH. Efficient photo-generation of the most reactive benzhydryl cations (3,5-F(2)-C(6)H(3))(2)CH(+) and (4-(CF(3))-C(6)H(4))(2)CH(+) was only achieved using the photo-leaving group P(p-Cl-C(6)H(4))(3) and the counter-anion SbF(6)(-) in CH(2)Cl(2). The lifetimes of the photogenerated benzhydryl cations depend greatly on the decay mechanisms, which can be reactions with the solvent, with the photo

  7. Soluble urokinase plasminogen activator receptor is in contrast to high-sensitive C-reactive-protein associated with coronary artery calcifications in healthy middle-aged subjects

    DEFF Research Database (Denmark)

    Sørensen, Mette Hjortdal; Gerke, Oke; Eugen-Olsen, Jesper

    2014-01-01

    OBJECTIVE: The main objective of this study was to investigate the association between two markers of low-grade inflammation; soluble urokinase plasminogen activator receptor (suPAR) and high-sensitive C-reactive protein (hs-CRP); and coronary artery calcification (CAC) score detected by cardiac ...

  8. Coordination of voltage and reactive power control in the extra high voltage substations based on the example of solutions applied in the national power system

    Directory of Open Access Journals (Sweden)

    Dariusz Kołodziej

    2012-06-01

    Full Text Available This paper presents examples of coordination between automatic voltage and reactive power control systems (ARST covering adjacent and strongly related extra high voltage substations. Included are conclusions resulting from the use of these solutions. The Institute of Power Engineering, Gdańsk Division has developed and deployed ARST systems in the national power system for a dozen or so years.

  9. High sensitivity C reactive protein as a prognostic marker in patients with mild to moderate aortic valve stenosis during lipid-lowering treatment

    DEFF Research Database (Denmark)

    Blyme, Adam; Asferg, Camilla; Nielsen, Olav W

    2015-01-01

    AIMS: To assess the prognostic importance of high-sensitive C reactive protein (hsCRP) in patients with mild to moderate aortic valve stenosis during placebo or simvastatin/ezetimibe treatment in Simvastatin and Ezetimibe in Aortic Stenosis (SEAS). METHODS AND RESULTS: In 1620 SEAS patients, we m...

  10. Highly oriented δ-Bi2O3 thin films stable at room temperature synthesized by reactive magnetron sputtering

    DEFF Research Database (Denmark)

    Lunca Popa, P.; Sønderby, S.; Kerdsongpanya, S.

    2013-01-01

    We report the synthesis by reactive magnetron sputtering and structural characterization of highly (111)-oriented thin films of δ–Bi2O3. This phase is obtained at a substrate temperature of 150–200 °C in a narrow window of O2/Ar ratio in the sputtering gas (18%–20%). Transmission electron...

  11. Multi-Wave Prospective Examination of the Stress-Reactivity Extension of Response Styles Theory of Depression in High-Risk Children and Early Adolescents

    Science.gov (United States)

    Abela, John R. Z.; Hankin, Benjamin L.; Sheshko, Dana M.; Fishman, Michael B.; Stolow, Darren

    2012-01-01

    The current study tested the stress-reactivity extension of response styles theory of depression (Nolen-Hoeksema "Journal of Abnormal Psychology" 100:569-582, 1991) in a sample of high-risk children and early adolescents from a vulnerability-stress perspective using a multi-wave longitudinal design. In addition, we examined whether obtained…

  12. Neuroendocrine correlates of emotional reactivity and coping in male rats from the Roman high (RHA/Verh)- and low (RLA/Verh)-avoidance lines

    NARCIS (Netherlands)

    Steimer, T.; la Fleur, S.; Schulz, P. E.

    1997-01-01

    The Roman high (RHA/Verh)- and low (RLA/Verh)-avoidance rats, originally selected and bred for rapid vs. poor acquisition of a two-way active avoidance response, differ in emotional reactivity and sensitivity to stressors in various other test situations. These behavioral differences are associated

  13. Biological variation and reference intervals for circulating osteopontin, osteoprotegerin, total soluble receptor activator of nuclear factor kappa B ligand and high-sensitivity C-reactive protein

    DEFF Research Database (Denmark)

    Sennels, Henriette Pia; Jacobsen, S; Jensen, T

    2007-01-01

    Objective. Monitoring inflammatory diseases and osteoclastogenesis with osteopontin (OPN), osteoprotegerin (OPG), total soluble receptor activator of nuclear factor kappa B ligand (total sRANKL) and high-sensitivity C-reactive protein (hsCRP) has recently attracted increased interest. The purpose...

  14. Allogeneic HLA-A*02-Restricted WT1-Specific T Cells from Mismatched Donors Are Highly Reactive but Show Off-Target Promiscuity

    NARCIS (Netherlands)

    Falkenburg, Willem J. J.; Melenhorst, J. Joseph; van de Meent, Marian; Kester, Michel G. D.; Hombrink, Pleun; Heemskerk, Mirjam H. M.; Hagedoorn, Renate S.; Gostick, Emma; Price, David A.; Falkenburg, J. H. Frederik; Barrett, A. John; Jedema, Inge

    2011-01-01

    T cells recognizing tumor-associated Ags such as Wilms tumor protein (WT1) are thought to exert potent antitumor reactivity. However, no consistent high-avidity T cell responses have been demonstrated in vaccination studies with WT1 as target in cancer immunotherapy. The aim of this study was to

  15. Effects of several types of biomass fuels on the yield, nanostructure and reactivity of soot from fast pyrolysis at high temperatures

    DEFF Research Database (Denmark)

    Trubetskaya, Anna; Jensen, Peter Arendt; Jensen, Anker Degn

    2016-01-01

    This study presents the effect of biomass origin on the yield, nanostructure and reactivity of soot. Soot was produced from wood and herbaceous biomass pyrolysis at high heating rates and at temperatures of 1250 and 1400 °C in a drop tube furnace. The structure of solid residues was characterized...

  16. High sensitive C-reactive protein-Effective tool in determining postoperative recovery in lumbar disc disease

    Directory of Open Access Journals (Sweden)

    Tushar Narayan Rathod

    2014-01-01

    Full Text Available Background: It is common in medical practice to see patients having persistent pain and radiculopathy even after undergoing discectomy surgery. Inflammatory cytokines, such as interleukins are produced at the site of disc herniation and are now considered responsible for the pain perceived by the patient. This study has used high sensitive C-reactive protein (HSCRP assay for predicting inflammation around the nerve roots on very same principle, which has used HSCRP for predicting coronary artery diseases in current clinical practice. Thus, purpose of this study is to test whether HSCRP can stand as an objective tool to predict postoperative recovery in patients undergoing lumbar discectomy. That is, to study association between preoperative HSCRP blood level and postoperative recovery with the help of modified Oswestry Back Disability Score. Materials and Methods: A study group consisting of 50 cases of established lumbar disc disease and control group of 50 normal subjects, matched with the study group. Both the study and control groups were subjected to detailed evaluation with the help of modified Oswestry Low Back Pain Scale both pre and postoperatively at 3 months, 6 months and 1-year. The preoperative blood samples were analyzed to assess the HSCRP concentration. All the cases underwent surgery over a period of 1-year by the same surgeon. Results: The level of HSCRP in the study group was between 0.050- and 0.710 mg/dL and in the control group, 0.005-0.020 mg/dL. There was highly significant positive correlation between preoperative HSCRP level and postoperative score at P 10 points, while those with HSCRP level in the range of 0.470 ± 0.163 mg/dL, showed poor recovery (score improved < 10 points. Conclusion: HSCRP will serve as a good supplementary prognostic marker for operative decision making in borderline and troublesome cases of lumbar disc disease.

  17. High-sensitivity Lens culinaris agglutinin-reactive alpha-fetoprotein assay predicts early detection of hepatocellular carcinoma.

    Science.gov (United States)

    Kumada, Takashi; Toyoda, Hidenori; Tada, Toshifumi; Kiriyama, Seiki; Tanikawa, Makoto; Hisanaga, Yasuhiro; Kanamori, Akira; Tanaka, Junko; Kagebayashi, Chiaki; Satomura, Shinji

    2014-03-01

    Prognosis of patients with hepatocellular carcinoma (HCC) remains poor because HCC is frequently diagnosed late. Therefore, regular surveillance has been recommended to detect HCC at the early stage when curative treatments can be applied. HCC biomarkers, including Lens culinaris agglutinin-reactive fraction of alpha-fetoprotein (AFP-L3), are widely used for surveillance in Japan. A newly developed immunoassay system measures AFP-L3 % with high sensitivity. This retrospective study aimed to evaluate clinical utility of high-sensitivity AFP-L3 (hs-AFP-L3) as a predictor of early stage HCC in surveillance at a single site. Of consecutive 2830 patients in the surveillance between 2000 and 2009, 104 HCC-developed and 104 non-HCC patients were selected by eligibility criteria and propensity score matching. Samples were obtained from the HCC patients who had blood drawn annually for 3 years prior to HCC diagnosis. In the present study, hs-AFP-L3 was elevated 1 year prior to diagnosis in 34.3 % of patients. The survival rate of patients with the hs-AFP-L3 ≥ 7 % at 1 year prior to diagnosis was significantly lower than that of patients with hs-AFP-L3 < 7 %. Elevation of hs-AFP-L3 was early predictive of development of HCC even at low AFP levels and in absence of ultrasound findings of suspicious HCC. The hs-AFP-L3 should be added to surveillance programs with US because elevated hs-AFP-L3 may be a trigger to perform enhanced imaging modalities for confirmation of HCC.

  18. Synthesis of highly reactive polyisobutylene catalyzed by EtAlCl 2/Bis(2-chloroethyl) ether soluble complex in hexanes

    KAUST Repository

    Kumar, Rajeev Ananda

    2014-03-25

    The polymerization of isobutylene (IB) to yield highly reactive polyisobutylene (HR PIB) with high exo-olefin content using GaCl3 or FeCl3·diisopropyl ether complexes has been previously reported.1 In an effort to further improve polymerization rates and exo-olefin content, we have studied ethylaluminum dichloride (EADC) complexes with diisopropyl ether, 2-chloroethyl ethyl ether (CEEE), and bis(2-chloroethyl) ether (CEE) as catalysts in conjunction with tert-butyl chloride as initiator in hexanes at different temperatures. All three complexes were readily soluble in hexanes. Polymerization, however, was only observed with CEE. At 0 °C polymerization was complete in 5 min at [t-BuCl] = [EADC·CEE] = 10 mM and resulted in PIB with ∼70% exo-olefin content. Studies on complexation using ATR FTIR and 1H NMR spectroscopy revealed that at 1:1 stoichiometry a small amount of EADC remains uncomplexed. By employing an excess of CEE, exo-olefin contents increased up to 90%, while polymerization rates decreased only slightly. With decreasing temperature, polymerization rates decreased while molecular weights as well as exo-olefin contents increased, suggesting that isomerization has a higher activation energy than β-proton abstraction. Density functional theory (DFT) studies on the Lewis acid·ether binding energies indicated a trend consistent with the polymerization results. The polymerization mechanism proposed previously for Lewis acid·ether complexes1 adequately explains all the findings. © 2014 American Chemical Society.

  19. The relationship between serum homocysteine and highly sensitive C- reactive protein levels in children on regular hemodialysis

    Directory of Open Access Journals (Sweden)

    Manal Abdel-Salam

    2017-01-01

    Full Text Available Hyperhomocysteinemia has attracted a lot of attention in renal patients, not only because of its close relationship with renal function but also because it has been implicated as an independent cardiovascular risk factor in these patients. An increased level of C-reactive protein (CRP has been reported to be a strong predictor of cardiovascular mortality in hemodialysis (HD patients. The aim of this study was to assess the association between homocysteine (Hcy and highly sensitive CRP (hsCRP in cardiovascular risk prediction in children with chronic kidney disease (CKD on HD. This case-control study was conducted on 40 children with CKD on regular HD and 20 age- and sex-matched healthy children as controls. Their ages ranged from 4 to 18 years, and they were selected from the pediatric nephrology and HD unit at Al-Azhar University Hospital, during the period from May 2015 to April 2016. Complete blood count, serum ferritin, cholesterol, triglycerides, calcium, phosphorus, parathormone (PTH, Hcy, and hsCRP levels were measured in both groups. Measurements of anthropometry and blood pressure (BP were performed. There was a significant increase in serum Hcy levels in cases than controls; it was 17.22 ± 9.66 pmol/L and 6.32 ± 1.47 pmol/L, respectively (P <0.01. Furthermore, there was a significant increase in hsCRP in patients than controls; 2.73 ± 2.65 and 0.9 ± 0.85, respectively (P <0.01. There was a significant positive correlation between hsCRP and Hcy with BP, cholesterol, triglyceride, PTH, and ferritin levels. Our data highlighted the important correlation between serum Hcy and hsCRP to detect high-risk patients for subsequent cardiovascular disease and utility of preventive strategies that attenuate inflammatory risk.

  20. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems......, the need for mathematically based formal methodology is increasingly important. There are many books that look at particular methodologies for such systems. This book offers a more balanced introduction for graduate students and describes the various approaches, their strengths and weaknesses, and when...

  1. Reactive Systems

    DEFF Research Database (Denmark)

    Aceto, Luca; Ingolfsdottir, Anna; Larsen, Kim Guldstrand

    A reactive system comprises networks of computing components, achieving their goals through interaction among themselves and their environment. Thus even relatively small systems may exhibit unexpectedly complex behaviours. As moreover reactive systems are often used in safety critical systems, t...... into account. The book has arisen from various courses taught in Denmark and Iceland and is designed to give students a broad introduction to the area, with exercises throughout....

  2. THE INVESTIGATION OF BURNUP CHARACTERISTICS USING THE SERPENT MONTE CARLO CODE FOR A SODIUM COOLED FAST REACTOR

    Directory of Open Access Journals (Sweden)

    MEHMET E. KORKMAZ

    2014-06-01

    Full Text Available In this research, we investigated the burnup characteristics and the conversion of fertile 232Th into fissile 233U in the core of a Sodium-Cooled Fast Reactor (SFR. The SFR fuel assemblies were designed for burning 232Th fuel (fuel pin 1 and 233U fuel (fuel pin 2 and include mixed minor actinide compositions. Monte Carlo simulations were performed using Serpent Code1.1.19 to compare with CRAM (Chebyshev Rational Approximation Method and TTA (Transmutation Trajectory Analysis method in the burnup calculation mode. The total heating power generated in the system was assumed to be 2000 MWth. During the reactor operation period of 600 days, the effective multiplication factor (keff was between 0.964 and 0.954 and peaking factor is 1.88867.

  3. High Residual Collagen-Induced Platelet Reactivity Predicts Development of Restenosis in the Superficial Femoral Artery After Percutaneous Transluminal Angioplasty in Claudicant Patients

    Energy Technology Data Exchange (ETDEWEB)

    Gary, Thomas, E-mail: thomas.gary@medunigraz.at [Medical University of Graz, Division of Angiology, Department of Internal Medicine (Austria); Prüller, Florian, E-mail: florian.prueller@klinikum-graz.at; Raggam, Reinhard, E-mail: reinhard.raggam@klinikum-graz.at [Medical University of Graz, Clinical Institute of Medical and Chemical Laboratory Diagnostics (Austria); Mahla, Elisabeth, E-mail: elisabeth.mahla@medunigraz.at [Medical University of Graz, Department of Anesthesiology and Intensive Care Medicine (Austria); Eller, Philipp, E-mail: philipp.eller@medunigraz.at; Hafner, Franz, E-mail: franz.hafner@klinikum-graz.at; Brodmann, Marianne, E-mail: marianne.brodmann@medunigraz.at [Medical University of Graz, Division of Angiology, Department of Internal Medicine (Austria)

    2016-02-15

    PurposeAlthough platelet reactivity is routinely inhibited with aspirin after percutaneous angioplasty (PTA) in peripheral arteries, the restenosis rate in the superficial femoral artery (SFA) is high. Interaction of activated platelets and the endothelium in the region of intervention could be one reason for this as collagen in the subendothelium activates platelets.Materials and MethodsA prospective study evaluating on-site platelet reactivity during PTA and its influence on the development of restenosis with a total of 30 patients scheduled for PTA of the SFA. Arterial blood was taken from the PTA site after SFA; platelet function was evaluated with light transmission aggregometry. After 3, 6, 12, and 24 months, duplex sonography was performed and the restenosis rate evaluated.ResultsEight out of 30 patients developed a hemodynamically relevant restenosis (>50 % lumen narrowing) in the PTA region during the 24-month follow-up period. High residual collagen-induced platelet reactivity defined as AUC >30 was a significant predictor for the development of restenosis [adjusted odds ratio 11.8 (9.4, 14.2); P = .04].ConclusionsHigh residual collagen-induced platelet reactivity at the interventional site predicts development of restenosis after PTA of the SFA. Platelet function testing may be useful for identifying patients at risk.

  4. Resveratrol Prevents High Fluence Red Light-Emitting Diode Reactive Oxygen Species-Mediated Photoinhibition of Human Skin Fibroblast Migration.

    Directory of Open Access Journals (Sweden)

    Andrew Mamalis

    Full Text Available Skin fibrosis is a significant medical problem that leads to a functional, aesthetic, and psychosocial impact on quality-of-life. Light-emitting diode-generated 633-nm red light (LED-RL is part of the visible light spectrum that is not known to cause DNA damage and is considered a safe, non-invasive, inexpensive, and portable potential alternative to ultraviolet phototherapy that may change the treatment paradigm of fibrotic skin disease.The goal of our study was to investigate the how reactive oxygen species (ROS free radicals generated by high fluence LED-RL inhibit the migration of skin fibroblasts, the main cell type involved in skin fibrosis. Fibroblast migration speed is increased in skin fibrosis, and we studied cellular migration speed of cultured human skin fibroblasts as a surrogate measure of high fluence LED-RL effect on fibroblast function. To ascertain the inhibitory role of LED-RL generated ROS on migration speed, we hypothesized that resveratrol, a potent antioxidant, could prevent the photoinhibitory effects of high fluence LED-RL on fibroblast migration speed.High fluence LED-RL generated ROS were measured by flow cytometry analysis using dihydrorhodamine (DHR. For purposes of comparison, we assessed the effects of ROS generated by hydrogen peroxide (H2O2 on fibroblast migration speed and the ability of resveratrol, a well known antioxidant, to prevent LED-RL and H2O2 generated ROS-associated changes in fibroblast migration speed. To determine whether resveratrol could prevent the high fluence LED-RL ROS-mediated photoinhibition of human skin fibroblast migration, treated cells were incubated with resveratrol at concentrations of 0.0001% and 0.001% for 24 hours, irradiated with high fluences LED-RL of 480, 640, and 800 J/cm2.High fluence LED-RL increases intracellular fibroblast ROS and decreases fibroblast migration speed. LED-RL at 480, 640 and 800 J/cm2 increased ROS levels to 132.8%, 151.0%, and 158.4% relative to matched

  5. Resveratrol Prevents High Fluence Red Light-Emitting Diode Reactive Oxygen Species-Mediated Photoinhibition of Human Skin Fibroblast Migration.

    Science.gov (United States)

    Mamalis, Andrew; Koo, Eugene; Isseroff, R Rivkah; Murphy, William; Jagdeo, Jared

    2015-01-01

    Skin fibrosis is a significant medical problem that leads to a functional, aesthetic, and psychosocial impact on quality-of-life. Light-emitting diode-generated 633-nm red light (LED-RL) is part of the visible light spectrum that is not known to cause DNA damage and is considered a safe, non-invasive, inexpensive, and portable potential alternative to ultraviolet phototherapy that may change the treatment paradigm of fibrotic skin disease. The goal of our study was to investigate the how reactive oxygen species (ROS) free radicals generated by high fluence LED-RL inhibit the migration of skin fibroblasts, the main cell type involved in skin fibrosis. Fibroblast migration speed is increased in skin fibrosis, and we studied cellular migration speed of cultured human skin fibroblasts as a surrogate measure of high fluence LED-RL effect on fibroblast function. To ascertain the inhibitory role of LED-RL generated ROS on migration speed, we hypothesized that resveratrol, a potent antioxidant, could prevent the photoinhibitory effects of high fluence LED-RL on fibroblast migration speed. High fluence LED-RL generated ROS were measured by flow cytometry analysis using dihydrorhodamine (DHR). For purposes of comparison, we assessed the effects of ROS generated by hydrogen peroxide (H2O2) on fibroblast migration speed and the ability of resveratrol, a well known antioxidant, to prevent LED-RL and H2O2 generated ROS-associated changes in fibroblast migration speed. To determine whether resveratrol could prevent the high fluence LED-RL ROS-mediated photoinhibition of human skin fibroblast migration, treated cells were incubated with resveratrol at concentrations of 0.0001% and 0.001% for 24 hours, irradiated with high fluences LED-RL of 480, 640, and 800 J/cm2. High fluence LED-RL increases intracellular fibroblast ROS and decreases fibroblast migration speed. LED-RL at 480, 640 and 800 J/cm2 increased ROS levels to 132.8%, 151.0%, and 158.4% relative to matched controls

  6. Neutron fluence effects on SLOWPOKE-2 beryllium reflector composition and reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Puig, Francesc, E-mail: fpuig@anl.gov [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439 (United States); Dennis, Haile, E-mail: haile.dennis02@uwimona.edu.jm [International Centre for Environmental and Nuclear Sciences, 2 Anguilla Close, University of the West Indies, Mona, Kingston 7 (Jamaica)

    2016-08-15

    Highlights: • SLOWPOKE-2 reflector composition evolution estimated using two different methods. • Reactivity effects of reflector composition changes calculated using MCNP5. • Impurities depletion dominates over poisons buildup, increasing reactivity. • Results contradict previously published behavior estimates for MNSR reactors. • Identified main factors explaining the observed prediction discrepancies. - Abstract: Within the scope of the conversion process from HEU to LEU of the Jamaican SLOWPOKE-2 reactor (JM-1), the effects of the neutron fluence on the beryllium reflector composition, and the corresponding effect on reactivity throughout the life of the reactor core, have been studied. Two different methods have been used and compared involving MCNP5, ORIGEN2.2, ORIGEN-S and COUPLE codes, reaching excellent agreement between them. The neutron flux profile and energy spectrum specific to the beryllium reflectors of this reactor design have been taken into account to analyze several scenarios, comprising both real and hypothetical conditions and involving different initial reflector compositions and reactor burnups. The analysis has been extended to provide estimates for the similar MNSR reactor design and compared with previously published predictions for the Syrian MNSR. The results show small overall reactivity effects in most cases, being dominated by impurity depletion as opposed to poison buildup, contrarily to what generally occurs in beryllium reflected reactors of far higher power and to MNSR predictions. The resulting reactivity increases are typically of less than 0.4 mk for usual impurity levels and maximum HEU core burnup achievable.

  7. Simulation of Low-Enriched Uranium (LEU) Burnup in Russian VVER Reactors with the HELIOS Code Package

    Energy Technology Data Exchange (ETDEWEB)

    Murphy, B.D.; Kravchenko, J.; Lazarenko, A.; Pavlovitchev, A.; Sidorenko, V.; Chetverikov, A.

    2000-03-01

    The HELIOS reactor-physics computer program system was used to simulate the burnup of UO{sub 2} fuel in three VVER reactors. The manner in which HELIOS was used in these simulations is described. Predictions of concentrations for actinides up to {sup 244}Cm and for isotopes of neodymium were compared with laboratory-measured values. Reasonable agreement between calculated and measured values was seen for experimental samples from a fuel rod in the interior of an assembly.

  8. In Comparative Analysis for Fuel Burnup of Fuel Assembly Designs for the 300 kW Small Medical Reactor

    Science.gov (United States)

    Sambuu, Odmaa; Nanzad, Norov

    2009-03-01

    A 300 kW small medical reactor was designed to be used for boron neutron capture therapy (BNCT) at KAIST in 1996 [1]. In this paper, analysis for the core life cycle of the original design of the BNCT facility and modifications of the fuel assembly configuration and enrichment to get a proper life cycle were performed and a criticality, neutron flux distribution and fuel burnup calculations were carried out.

  9. OECD/NEA burnup credit criticality benchmarks phase IIIA: Criticality calculations of BWR spent fuel assemblies in storage and transport

    Energy Technology Data Exchange (ETDEWEB)

    Okuno, Hiroshi; Naito, Yoshitaka [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ando, Yoshihira [Toshiba Corp., Kawasaki, Kanagawa (Japan)

    2000-09-01

    The report describes the final results of Phase IIIA Benchmarks conducted by the Burnup Credit Criticality Calculation Working Group under the auspices of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development (OECD/NEA). The benchmarks are intended to confirm the predictive capability of the current computer code and data library combinations for the neutron multiplication factor (k{sub eff}) of a layer of irradiated BWR fuel assembly array model. In total 22 benchmark problems are proposed for calculations of k{sub eff}. The effects of following parameters are investigated: cooling time, inclusion/exclusion of FP nuclides and axial burnup profile, and inclusion of axial profile of void fraction or constant void fractions during burnup. Axial profiles of fractional fission rates are further requested for five cases out of the 22 problems. Twenty-one sets of results are presented, contributed by 17 institutes from 9 countries. The relative dispersion of k{sub eff} values calculated by the participants from the mean value is almost within the band of {+-}1%{delta}k/k. The deviations from the averaged calculated fission rate profiles are found to be within {+-}5% for most cases. (author)

  10. Pebble Bed Reactors Design Optimization Methods and their Application to the Pebble Bed Fluoride Salt Cooled High Temperature Reactor (PB-FHR)

    Science.gov (United States)

    Cisneros, Anselmo Tomas, Jr.

    The Fluoride salt cooled High temperature Reactor (FHR) is a class of advanced nuclear reactors that combine the robust coated particle fuel form from high temperature gas cooled reactors, direct reactor auxillary cooling system (DRACS) passive decay removal of liquid metal fast reactors, and the transparent, high volumetric heat capacitance liquid fluoride salt working fluids---flibe (33%7Li2F-67%BeF)---from molten salt reactors. This combination of fuel and coolant enables FHRs to operate in a high-temperature low-pressure design space that has beneficial safety and economic implications. In 2012, UC Berkeley was charged with developing a pre-conceptual design of a commercial prototype FHR---the Pebble Bed- Fluoride Salt Cooled High Temperature Reactor (PB-FHR)---as part of the Nuclear Energy University Programs' (NEUP) integrated research project. The Mark 1 design of the PB-FHR (Mk1 PB-FHR) is 236 MWt flibe cooled pebble bed nuclear heat source that drives an open-air Brayton combine-cycle power conversion system. The PB-FHR's pebble bed consists of a 19.8% enriched uranium fuel core surrounded by an inert graphite pebble reflector that shields the outer solid graphite reflector, core barrel and reactor vessel. The fuel reaches an average burnup of 178000 MWt-d/MT. The Mk1 PB-FHR exhibits strong negative temperature reactivity feedback from the fuel, graphite moderator and the flibe coolant but a small positive temperature reactivity feedback of the inner reflector and from the outer graphite pebble reflector. A novel neutronics and depletion methodology---the multiple burnup state methodology was developed for an accurate and efficient search for the equilibrium composition of an arbitrary continuously refueled pebble bed reactor core. The Burnup Equilibrium Analysis Utility (BEAU) computer program was developed to implement this methodology. BEAU was successfully benchmarked against published results generated with existing equilibrium depletion codes VSOP

  11. A state of the Art report on Manufacturing technology of high burn-up fuel cladding

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyeong Ho; Nam, Cheol; Baek, Jong Hyuk; Choi, Byung Kwon; Park, Sang Yoon; Lee, Myung Ho; Jeong, Yong Hwan

    1999-09-01

    In order to manufacturing the prototype fuel cladding, overall manufacturing processes and technologies should be thoroughly understood on the manufacturing processes and technologies of foreign cladding tubes. Generally, the important technology related to fuel cladding tube manufacturing processes for PWRs/PHWRs is divided into three stages. The first stage is to produce the zirconium sponge from zirconium sand, the second stage is to produce the zircaloy shell or TREX from zirconium sponge ingot and finally, cladding is produced from TREX or zircaloy shell. Therefore, the manufacturing processes including the first and second stages are described in brief in this technology report in order to understand the whole fuel cladding manufacturing processes. (author)

  12. A rapid one-step kinetics-based immunoassay procedure for the highly-sensitive detection of C-reactive protein

    OpenAIRE

    sprotocols

    2014-01-01

    Authors: Sandeep Kumar Vashist, Gregor Czilwik, Thomas van Oordt, Felix von Stetten, Roland Zengerle, E. Marion Schneider & John H.T. Luong ### Abstract A rapid one-step kinetics-based sandwich enzyme-linked immunosorbent (ELISA) procedure has been developed for highly-sensitive detection of C-reactive protein (CRP) in less than 30 min. With minimal process steps, the procedure is highly simplified and cost-effective. The analysis only involves sequentially the formation of a sandwic...

  13. Reactivation of normal faults as high-angle reverse faults due to low frictional strength: Experimental data from the Moonlight Fault Zone, New Zealand

    Science.gov (United States)

    Smith, S. A. F.; Tesei, T.; Scott, J. M.; Collettini, C.

    2017-12-01

    Large normal faults are frequently reactivated as high-angle reverse faults during basin inversion. Elevated fluid pressure is commonly invoked to explain high-angle reverse slip. Analogue and numerical modeling have demonstrated that frictional weakening may also promote high-angle reverse slip, but there are currently no frictional strength measurements available for fault rocks collected from large high-angle reverse faults. To test the hypothesis that frictional weakening could facilitate high-angle reverse slip, we performed single- and double-direct friction experiments on fault rocks collected from the Moonlight Fault Zone in New Zealand, a basin-bounding normal fault zone that was reactivated as a high-angle reverse fault (present-day dip angle 60°-75°). The fault core is exposed in quartzofeldspathic schists exhumed from c. 4-8 km depth and contains a <20 m thick sequence of breccias, cataclasites and foliated cataclasites that are enriched in chlorite and muscovite. Friction experiments on water-saturated, intact samples of foliated cataclasite at room temperature and normal stresses up to 75 MPa yielded friction coefficients of 0.19<μ < 0.25. On the assumption of horizontal maximum compressive stress, reactivation analysis indicates that a friction coefficient of <0.25 will permit slip on high-angle reverse faults at hydrostatic (or even sub-hydrostatic) fluid pressures. Since foliated and phyllosilicate-rich fault rocks are common in large reactivated fault zones at basement depths, long-term frictional weakening is likely to act in concert with episodic build-ups of fluid pressure to promote high-angle reverse slip during basin inversion.

  14. Calcium dobesilate reduces endothelin-1 and high-sensitivity C-reactive protein serum levels in patients with diabetic retinopathy.

    Science.gov (United States)

    Javadzadeh, Alireza; Ghorbanihaghjo, Amir; Adl, Farzad Hami; Andalib, Dima; Khojasteh-Jafari, Hassan; Ghabili, Kamyar

    2013-01-01

    To determine the benefits of calcium dobesilate (CaD) administration on endothelial function and inflammatory status in patients with diabetic retinopathy through measurement of serum levels of endothelin-1 and high-sensitivity C-reactive protein (hsCRP). In a double-blind, randomized clinical trial, 90 patients with either severe nonproliferative or proliferative diabetic retinopathy and with blood glucose level of 120-200 mg/dl were randomly allocated to treatment with either CaD tablets (500 mg daily) or placebo for 3 months. Visual acuity, intraocular pressure, and macular status were performed before the study. The serum levels of endothelin-1 and hsCRP were evaluated in both groups before and at the third month of the trial. The median serum level of hsCRP significantly differed between the groups 3 months following the CaD or placebo administration (2.2 mg/l in the CaD group versus 3.7 mg/l in the placebo group, p=0.01). The mean endothelin-1 serum level was 0.69±0.32 pg/ml in the CaD group and 0.86±0.30 pg/ml in the placebo group (p=0.01). Furthermore, in the CaD group, the serum levels of both endothelin-1 and hsCRP were significantly decreased 3 months after administration of CaD (p<0.001). Administration of the CaD in the patients with diabetic retinopathy may reduce the serum levels of endothelin-1 and hsCRP. This might imply amelioration of the endothelial function and inflammatory status following CaD therapy in these patients.

  15. The cardiovascular markers copeptin and high-sensitive C-reactive protein decrease following specific therapy for primary aldosteronism.

    Science.gov (United States)

    Remde, Hanna; Dietz, Anna; Emeny, Rebecca; Riester, Anna; Peters, Annette; de Las Heras Gala, Tonia; Then, Cornelia; Seissler, Jochen; Beuschlein, Felix; Reincke, Martin; Quinkler, Marcus

    2016-10-01

    Copeptin and high-sensitive C-reactive protein (hsCRP) are biomarkers associated with increased mortality in patients with cardiovascular and cerebrovascular disease as well as in the general population. No data exist regarding these markers in patients with primary aldosteronism. To evaluate copeptin and hsCRP levels as cardiovascular risk markers in primary aldosteronism patients. A total of 113 primary aldosteronism patients (64% male) from two centers of the prospective German Conn's Registry were identified, for whom a full data set and blood samples at baseline and follow-up (14 ± 3.4 months) after initiation of specific primary aldosteronism treatment were available. These cases were matched 1 : 3 (n = 339) for sex, renal function, BMI, age and SBP with participants from the Cooperative Health Research in the Region of Augsburg F4 survey. Copeptin and hsCRP were determined by sandwich fluoroimmunoassay. HsCRP was significantly higher in primary aldosteronism patients at baseline compared with matched controls. Following specific therapy, hsCRP and copeptin decreased significantly in primary aldosteronism patients [median (25th and 75th percentile): 1.6 (0.8, 3.4) to 1.2 (0.6, 2.1) mg/l, P copeptin levels at baseline and follow-up compared with women. The combination of sex, hypokalemia, lateralization index and blood pressure were the best predictors of outcome. However, copeptin and hsCRP had no predictive value despite the association of lower copeptin levels with better outcome regarding cure of primary aldosteronism. Copeptin and hsCRP levels decrease following specific primary aldosteronism therapy reflecting successful cardiovascular risk reduction. However, they are no independent predictors regarding cure of primary aldosteronism.

  16. Serum copper, zinc and high-sensitivity C-reactive protein in short and long sleep duration in ageing men.

    Science.gov (United States)

    Luojus, Maria K; Lehto, Soili M; Tolmunen, Tommi; Elomaa, Antti-Pekka; Kauhanen, Jussi

    2015-10-01

    Serum levels of zinc and copper have been proposed to associate with sleep duration. Mechanisms, such as inflammatory processes, have been suggested to relate this association. However, earlier studies have been conducted in small sample sizes. Human studies investigating the suggested associations while controlling for potential confounding factors are lacking. Population-based data consisted of 2570 men (aged 42-60 years) from Eastern Finland. The participants reported an estimate of their sleep duration. The serum levels of zinc (S-Zn), copper (S-Cu) and high-sensitivity C-reactive protein (hs-CRP) were measured. Analysis of covariance was used for multivariate analyses. S-Zn levels and Zn/Cu ratio were lowest in ≤6h sleep. S-Cu levels were highest in ≥10h sleep. Elevated levels (>3.0mmol/l) of hs-CRP were observed in ≤6h and ≥10h sleep. After adjustments for age, cumulative smoking history (pack-years), alcohol consumption (g/week), Human Population Laboratory depression scale scores, physical activity (kcal/day), cardiometabolic syndrome, and cardiovascular disease history, sleep duration was significantly associated with levels of both S-Cu and hs-CRP. The association with S-Cu remained statistically significant following further adjustment for hs-CRP in the same model. Our data suggests an association between S-Cu and sleep duration in ageing men. Elevated inflammation (measured as serum hs-CRP) does not explain this relationship. Mechanisms underlying the relationship require further investigation, as S-Cu may contribute to sleep regulation through pro-oxidative processes and copper-dependent N-methyl-d-aspartate receptor activity. Copyright © 2015 Elsevier GmbH. All rights reserved.

  17. An adaptive sparse-grid high-order stochastic collocation method for Bayesian inference in groundwater reactive transport modeling

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guannan [ORNL; Webster, Clayton G [ORNL; Gunzburger, Max D [ORNL

    2012-09-01

    Although Bayesian analysis has become vital to the quantification of prediction uncertainty in groundwater modeling, its application has been hindered due to the computational cost associated with numerous model executions needed for exploring the posterior probability density function (PPDF) of model parameters. This is particularly the case when the PPDF is estimated using Markov Chain Monte Carlo (MCMC) sampling. In this study, we develop a new approach that improves computational efficiency of Bayesian inference by constructing a surrogate system based on an adaptive sparse-grid high-order stochastic collocation (aSG-hSC) method. Unlike previous works using first-order hierarchical basis, we utilize a compactly supported higher-order hierar- chical basis to construct the surrogate system, resulting in a significant reduction in the number of computational simulations required. In addition, we use hierarchical surplus as an error indi- cator to determine adaptive sparse grids. This allows local refinement in the uncertain domain and/or anisotropic detection with respect to the random model parameters, which further improves computational efficiency. Finally, we incorporate a global optimization technique and propose an iterative algorithm for building the surrogate system for the PPDF with multiple significant modes. Once the surrogate system is determined, the PPDF can be evaluated by sampling the surrogate system directly with very little computational cost. The developed method is evaluated first using a simple analytical density function with multiple modes and then using two synthetic groundwater reactive transport models. The groundwater models represent different levels of complexity; the first example involves coupled linear reactions and the second example simulates nonlinear ura- nium surface complexation. The results show that the aSG-hSC is an effective and efficient tool for Bayesian inference in groundwater modeling in comparison with conventional

  18. Optical properties and structure of HfO{sub 2} thin films grown by high pressure reactive sputtering

    Energy Technology Data Exchange (ETDEWEB)

    MartInez, F L [Departamento de Electronica y TecnologIa de Computadoras, Universidad Politecnica de Cartagena, Campus Universitario Muralla del Mar, E-30202 Cartagena (Spain); Toledano-Luque, M [Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, E-28040 Madrid (Spain); GandIa, J J [Departamento de EnergIa, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain); Carabe, J [Departamento de EnergIa, CIEMAT, Avda. Complutense 22, E-28040 Madrid (Spain); Bohne, W [Hahn-Meitner-Institut Berlin, Abteilung SF4, D-14109 Berlin (Germany); Roehrich, J [Hahn-Meitner-Institut Berlin, Abteilung SF4, D-14109 Berlin (Germany); Strub, E [Hahn-Meitner-Institut Berlin, Abteilung SF4, D-14109 Berlin (Germany); Martil, I [Departamento de Fisica Aplicada III, Universidad Complutense de Madrid, E-28040 Madrid (Spain)

    2007-09-07

    Thin films of hafnium oxide (HfO{sub 2}) have been grown by high pressure reactive sputtering on transparent quartz substrates (UV-grade silica) and silicon wafers. Deposition conditions were adjusted to obtain polycrystalline as well as amorphous films. Optical properties of the films deposited on the silica substrates were investigated by transmittance and reflectance spectroscopy in the ultraviolet, visible and near infrared range. A numerical analysis method that takes into account the different surface roughness of the polycrystalline and amorphous films was applied to calculate the optical constants (refractive index and absorption coefficient). Amorphous films were found to have a higher refractive index and a lower transparency than polycrystalline films. This is attributed to a higher density of the amorphous samples, which was confirmed by atomic density measurements performed by heavy-ion elastic recoil detection analysis. The absorption coefficient gave an excellent fit to the Tauc law (indirect gap), which allowed a band gap value of 5.54 eV to be obtained. The structure of the films (amorphous or polycrystalline) was found to have no significant influence on the nature of the band gap. The Tauc plots also give information about the structure of the films, because the slope of the plot (the Tauc parameter) is related to the degree of order in the bond network. The amorphous samples had a larger value of the Tauc parameter, i.e. more order than the polycrystalline samples. This is indicative of a uniform bond network with percolation of the bond chains, in contrast to the randomly oriented polycrystalline grains separated by grain boundaries.

  19. Sex Differences in High Sensitivity C-Reactive Protein in Subjects with Risk Factors of Metabolic Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Vinicius Pacheco; Rocha, Helena Naly Miguens [Laboratório de Ciências do Exercício - Departamento de Fisiologia e Farmacologia - Universidade Federal Fluminense, Niterói, RJ (Brazil); Sales, Allan Robson Kluser [Unidade de Reabilitação Cardiovascular e Fisiologia do Exercício - Instituto do Coração (InCor) - Faculdade de Medicina da Universidade de São Paulo, São Paulo, SP (Brazil); Rocha, Natália Galito; Nóbrega, Antonio Claudio Lucas da, E-mail: anobrega@id.uff.br [Laboratório de Ciências do Exercício - Departamento de Fisiologia e Farmacologia - Universidade Federal Fluminense, Niterói, RJ (Brazil)

    2016-03-15

    Metabolic syndrome (MetS) is associated with a higher risk of all-cause mortality. High-sensitivity C-reactive protein (hsCRP) is a prototypic marker of inflammation usually increased in MetS. Women with MetS-related diseases present higher hsCRP levels than men with MetS-related diseases, suggesting sex differences in inflammatory markers. However, it is unclear whether serum hsCRP levels are already increased in men and/or women with MetS risk factors and without overt diseases or under pharmacological treatment. To determine the impact of the number of MetS risk factors on serum hsCRP levels in women and men. One hundred and eighteen subjects (70 men and 48 women; 36 ± 1 years) were divided into four groups according to the number of MetS risk factors: healthy group (CT; no risk factors), MetS ≤ 2, MetS = 3, and MetS ≥ 4. Blood was drawn after 12 hours of fasting for measurement of biochemical variables and hsCRP levels, which were determined by immunoturbidimetric assay. The groups with MetS risk factors presented higher serum hsCRP levels when compared with the CT group (p < 0.02). There were no differences in hsCRP levels among groups with MetS risk factors (p > 0.05). The best linear regression model to explain the association between MetS risk factors and hsCRP levels included waist circumference and HDL cholesterol (r = 0.40, p < 0.01). Women with MetS risk factors presented higher hsCRP levels when compared with men (p{sub sex} < 0.01). Despite the absence of overt diseases and pharmacological treatment, subjects with MetS risk factors already presented increased hsCRP levels, which were significantly higher in women than men at similar conditions.

  20. Sex Differences in High Sensitivity C-Reactive Protein in Subjects with Risk Factors of Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Vinicius Pacheco Garcia

    2016-03-01

    Full Text Available Abstract Background: Metabolic syndrome (MetS is associated with a higher risk of all-cause mortality. High-sensitivity C-reactive protein (hsCRP is a prototypic marker of inflammation usually increased in MetS. Women with MetS-related diseases present higher hsCRP levels than men with MetS-related diseases, suggesting sex differences in inflammatory markers. However, it is unclear whether serum hsCRP levels are already increased in men and/or women with MetS risk factors and without overt diseases or under pharmacological treatment. Objective: To determine the impact of the number of MetS risk factors on serum hsCRP levels in women and men. Methods One hundred and eighteen subjects (70 men and 48 women; 36 ± 1 years were divided into four groups according to the number of MetS risk factors: healthy group (CT; no risk factors, MetS ≤ 2, MetS = 3, and MetS ≥ 4. Blood was drawn after 12 hours of fasting for measurement of biochemical variables and hsCRP levels, which were determined by immunoturbidimetric assay. Results: The groups with MetS risk factors presented higher serum hsCRP levels when compared with the CT group (p 0.05. The best linear regression model to explain the association between MetS risk factors and hsCRP levels included waist circumference and HDL cholesterol (r = 0.40, p < 0.01. Women with MetS risk factors presented higher hsCRP levels when compared with men (psex < 0.01. Conclusions: Despite the absence of overt diseases and pharmacological treatment, subjects with MetS risk factors already presented increased hsCRP levels, which were significantly higher in women than men at similar conditions.

  1. Process- and optoelectronic-control of NiOx thin films deposited by reactive high power impulse magnetron sputtering

    Science.gov (United States)

    Keraudy, Julien; Delfour-Peyrethon, Brice; Ferrec, Axel; Garcia Molleja, Javier; Richard-Plouet, Mireille; Payen, Christophe; Hamon, Jonathan; Corraze, Benoît; Goullet, Antoine; Jouan, Pierre-Yves

    2017-05-01

    In this contribution, based on the analyses of the discharge behavior as well as final properties of the deposited Ni-O films during reactive high power impulse magnetron sputtering discharge, we have demonstrated that monitoring the oxygen flow rate leads to 4 different regimes of discharge. Tuning the oxygen partial pressure allows deposition of a large range of chemical compositions from pure nickel to nickel-deficient NiOx (x > 1) in the poisoned mode. Investigation of the plasma dynamics by time-resolved optical emission spectroscopy suggests that the discharge behavior in the poisoned mode principally comes from the higher contribution of both oxygen and argon ions in the total ionic current, leading to a change in the ion induced secondary electron emission coefficient. Additionally, material characterizations have revealed that optoelectronic properties of NiOx films can be easily tuned by adjusting the O/Ni ratio, which is influenced by the change of the oxygen flow rate. Stoichiometric NiO films (O/Ni ratio ˜ 1) are transparent in the visible range with a transmittance ˜80% and insulating as expected with an electrical resistivity ˜106 Ω cm. On the other hand, increasing the O/Ni > 1 leads to the deposition of more conductive coating (ρ ˜ 10 Ω cm) films with a lower transmittance ˜ 50%. These optoelectronic evolutions are accompanied by a band-gap narrowing 3.65 to 3.37 eV originating from the introduction of acceptor states between the Fermi level and the valence band maximum. In addition, our analysis has demonstrated that nickel vacancies are homogeneously distributed over the film thickness, explaining the p-type of the films.

  2. Reactive transport model of growth and methane production by high-temperature methanogens in hydrothermal regions of the subseafloor

    Science.gov (United States)

    Stewart, L. C.; Algar, C. K.; Topçuoğlu, B. D.; Fortunato, C. S.; Larson, B. I.; Proskurowski, G. K.; Butterfield, D. A.; Vallino, J. J.; Huber, J. A.; Holden, J. F.

    2014-12-01

    Hydrogenotrophic methanogens are keystone high-temperature autotrophs in deep-sea hydrothermal vents and tracers of habitability and biogeochemical activity in the hydrothermally active subseafloor. At Axial Seamount, nearly all thermophilic methanogens are Methanothermococcus and Methanocaldococcus species, making this site amenable to modeling through pure culture laboratory experiments coupled with field studies. Based on field microcosm incubations with 1.2 mM, 20 μM, or no hydrogen, the growth of methanogens at 55°C and 80°C is limited primarily by temperature and hydrogen availability, with ammonium amendment showing no consistent effect on total methane output. The Arrhenius constants for methane production by Methanocaldococcus jannaschii (optimum 82°C) and Methanothermococcus thermolithotrophicus (optimum 65°C) were determined in pure culture bottle experiments. The Monod constants for hydrogen concentration were measured by growing both organisms in a 2-liter chemostat at two dilution rates; 55°C, 65°C and 82°C; and variable hydrogen concentrations. M. jannaschii showed higher ks and Vmax constants than M. thermolithotrophicus. In the field, hydrogen and methane concentrations in hydrothermal end-member and low-temperature diffuse fluids were measured, and the concentrations of methanogens that grow at 55°C and 80°C in diffuse fluids were determined using most-probable-number estimates. Methane concentration anomalies in diffuse fluids relative to end-member hydrothermal concentrations and methanogen cell concentrations are being used to constrain a 1-D reactive transport model using the laboratory-determined Arrhenius and Monod constants for methane production by these organisms. By varying flow path length and subseafloor cell concentrations in the model, our goal is to determine solutions for the potential depth of the subseafloor biosphere coupled with the amount of methanogenic biomass it contains.

  3. Chemical burnup determination based on spectrophotometric measurement of total rare earth fission products, uranium, and plutonium

    Energy Technology Data Exchange (ETDEWEB)

    Marsh, S.F.; Ortiz, M.R.; Rein, J.E.

    1975-10-01

    A chemical burnup procedure incorporates the ion-exchange separation of uranium, plutonium, and total rare earth fission products (as the fission monitor) followed by the spectrophotometric determination of each. The separation involves retaining uranyl and plutonyl chloride complexes on a macroporous anion exchange column from 12 M HCl, whereas the rare earths and most fission products pass through. Subsequently, plutonium is eluted with 0.1 M HI-12 M HCl and uranium with 0.1 M HCl. From the initial effluent of the first column, the rare earth group is separated on a second column of either (1) macroporous anion exchange resin from HNO/sub 3/-CH/sub 3/OH, or (2) pellicular cation exchange particles from HCl-C/sub 2/H/sub 5/OH. The HNO/sub 3/--CH/sub 3/OH system normally is used to separate the rare earth group from fuel cladding elements and other fission products. The HCl--C/sub 2/H/sub 5/OH system additionally separates the rare earth group from americium. Arsenazo III is the chromogenic agent for the spectrophotometric determination of the separated uranium, plutonium, and rare earth fractions.

  4. Application of non-thermal plasma reactor for degradation and detoxification of high concentrations of dye Reactive Black 5 in water

    Directory of Open Access Journals (Sweden)

    Dojčinović Biljana P.

    2016-01-01

    Full Text Available Degradation and detoxification efficiency of high concentrations of commercially available reactive textile dye Reactive Black 5 solution (40, 80, 200, 500, 1000 mg L-1, were studied. Advanced oxidation processes in water falling film based dielectric barrier discharge as a non-thermal plasma reactor were used. For the first time, this reactor was used for the treatment of high concentrations of organic pollutants such as reactive textile dye Reactive Black 5 in water. Solution of the dye is treated by plasma as thin water solution film that is constantly regenerated. Basically, the reactor works as a continuous flow reactor and the electrical discharge itself takes place at the gas-liquid interphase. The dye solution was recirculated through the reactor with an applied energy density of 0-374 kJ L-1. Decolorization efficiency (% was monitored by UV-VIS spectrophotometric technique. Samples were taken after every recirculation (~ 22 kJ L-1 and decolorization percent was measured after 5 min and 24 h of plasma treatment. The efficiency of degradation (i.e. mineralization and possible degradation products were also tracked by determination of the chemical oxygen demand (COD and by ion chromatography (IC. Initial toxicity and toxicity of solutions after the treatment were studied with Artemia salina test organisms. Efficiency of decolorization decreased with the increase of the dye concentration. Complete decolorization, high mineralization and non-toxicity of the solution (<10 % were acomplished after plasma treatment using energy density of 242 kJ L-1, while the initial concentrations of Reactive Black 5 were 40 and 80 mg L-1. [Projekat Ministarstva nauke Republike Srbije, br. 172030 i br. 171034

  5. Emotional reactivity to incentive downshift as a correlated response to selection of high and low alcohol preferring mice and an influencing factor on ethanol intake.

    Science.gov (United States)

    Matson, Liana M; Grahame, Nicholas J

    2015-11-01

    Losing a job or significant other are examples of incentive loss that result in negative emotional reactions. The occurrence of negative life events is associated with increased drinking (Keyes, Hatzenbuehler, & Hasin, 2011). Further, certain genotypes are more likely to drink alcohol in response to stressful negative life events (Blomeyer et al., 2008; Covault et al., 2007). Shared genetic factors may contribute to alcohol drinking and emotional reactivity, but this relationship is not currently well understood. We used an incentive downshift paradigm to address whether emotional reactivity is elevated in mice predisposed to drink alcohol. We also investigated if ethanol drinking is influenced in High Alcohol Preferring mice that had been exposed to an incentive downshift. Incentive downshift procedures have been widely utilized to model emotional reactivity, and involve shifting a high reward group to a low reward and comparing the shifted group to a consistently rewarded control group. Here, we show that replicate lines of selectively bred High Alcohol Preferring mice exhibited larger successive negative contrast effects than their corresponding replicate Low Alcohol Preferring lines, providing strong evidence for a genetic association between alcohol drinking and susceptibility to the emotional effects of negative contrast. These mice can be used to study the shared neurological and genetic underpinnings of emotional reactivity and alcohol preference. Unexpectedly, an incentive downshift suppressed ethanol drinking immediately following an incentive downshift. This could be due to a specific effect of negative contrast on ethanol consumption or a suppressive effect on consummatory behavior in general. These data suggest that either alcohol intake does not provide the anticipated negative reinforcement, or that a single test was insufficient for animals to learn to drink following incentive downshift. However, the emotional intensity following incentive

  6. Reactive arthritis.

    Science.gov (United States)

    Keat, A

    1999-01-01

    Reactive arthritis is one of the spondyloarthropathy family of clinical syndromes. The clinical features are those shared by other members of the spondyloarthritis family, though it is distinguished by a clear relationship with a precipitating infection. Susceptibility to reactive arthritis is closely linked with the class 1 HLA allele B27; it is likely that all sub-types pre-dispose to this condition. The link between HLA B27 and infection is mirrored by the development of arthritis in HLA B27-transgenic rats. In this model, arthritis does not develop in animals maintained in a germ-free environment. Infections of the gastrointestinal, genitourinary and respiratory tract appear to provoke reactive arthritis and a wide range of pathogens has now been implicated. Although mechanistic parallels may exist, reactive arthritis is distinguished from Lyme disease, rheumatic fever and Whipple's disease by virtue of the distinct clinical features and the link with HLA B27. As in these conditions both antigens and DNA of several micro-organisms have been detected in joint material from patients with reactive arthritis. The role of such disseminated microbial elements in the provocation or maintenance of arthritis remains unclear. HLA B27-restricted T-cell responses to microbial antigens have been demonstrated and these may be important in disease pathogenesis. The importance of dissemination of bacteria from sites of mucosal infection and their deposition in joints has yet to be fully understood. The role of antibiotic therapy in the treatment of reactive arthritis is being explored; in some circumstances, both the anti-inflammatory and anti-microbial effects of certain antibiotics appear to be valuable. The term reactive arthritis should be seen as a transitory one, reflecting a concept which may itself be on the verge of replacement, as our understanding of the condition develops. Nevertheless it appropriately describes arthritis that is associated with demonstrable

  7. Highly functionalized organic nitrates in the southeast United States: Contribution to secondary organic aerosol and reactive nitrogen budgets

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ben H.; Mohr, Claudia; Lopez-Hilfiker, Felipe D.; Lutz, Anna; Hallquist, Mattias; Lee, Lance; Romer, Paul; Cohen, Ronald C.; Iyer, Siddharth; Kurtén, Theo; Hu, Weiwei; Day, Douglas A.; Campuzano-Jost, Pedro; Jimenez, Jose L.; Xu, Lu; Ng, Nga Lee; Guo, Hongyu; Weber, Rodney J.; Wild, Robert J.; Brown, Steven S.; Koss, Abigail; de Gouw, Joost; Olson, Kevin; Goldstein, Allen H.; Seco, Roger; Kim, Saewung; McAvey, Kevin; Shepson, Paul B.; Starn, Tim; Baumann, Karsten; Edgerton, Eric S.; Liu, Jiumeng; Shilling, John E.; Miller, David O.; Brune, William; Schobesberger, Siegfried; D' Ambro, Emma L.; Thornton, Joel A.

    2016-01-25

    and Aerosol Study (SOAS). We compare these speciated measurements to total unspeciated particulate organic nitrate measured by three independent methods, and analyze using a zero-dimensional box model the diel cycles of individual components to elucidate differential source and sink terms. Biogenic volatile organic compounds (VOCs), including isoprene, monoterpenes, and sesquiterpenes appear to dominate the ON sources during SOAS. We show that the molecular compositions that dominate the particle-phase are significantly more oxygenated than the most abundant gas-phase counterparts, consistent with volatility and solubility driven partitioning requirements. However, the detailed mechanisms by which most of these ON arise are not yet clear. These speciated measurements put a strong constraint on the extent to which ON directly contribute to SOA in regions with high biogenic hydrocarbon emissions, and illustrate that the fate of particulate ON can have significant implications for SOA and the reactive nitrogen budget.

  8. Simulating reactive nitrogen, carbon monoxide, and ozone in California during ARCTAS-CARB 2008 with high wildfire activity

    Science.gov (United States)

    Cai, Chenxia; Kulkarni, Sarika; Zhao, Zhan; Kaduwela, Ajith P.; Avise, Jeremy C.; DaMassa, John A.; Singh, Hanwant B.; Weinheimer, Andrew J.; Cohen, Ronald C.; Diskin, Glenn S.; Wennberg, Paul; Dibb, Jack E.; Huey, Greg; Wisthaler, Armin; Jimenez, Jose L.; Cubison, Michael J.

    2016-03-01

    Predictions of O3, CO, total NOy and individual NOy species (NO, NO2, HNO3, PAN, alkyl nitrates and aerosol nitrate) from a fine resolution regional air quality modeling system for the South Coast Air Basin (SoCAB) and San Joaquin Valley Air Basin (SJVAB) of California are presented and evaluated for the 2008 ARCTAS-CARB campaign. The measurements of the chemical compounds from the fire plumes during the field campaign allow for the evaluation of the model's ability to simulate fire-influenced air masses as well. In general, the model successfully simulated the broad spatial distribution of chemical compounds in both air basins as well as the variation within the basins. Using inventories that reflect 2008 emissions levels, the model performed well in simulating NOx (NO + NO2) in SoCAB. Therefore, the under prediction of O3 over these areas is more likely caused by uncertainties with the VOC emissions, chemistry, or discrepancies in the meteorology. The model did not capture the relatively high levels of O3, and some reactive nitrogen species that were measured off shore of the SoCAB, indicating potential missing sources or the transport from on shore to off shore was not successfully captured. In SJVAB, the model had good performance in simulating different chemical compounds in the Fresno and Arvin areas. However, enhanced concentrations of O3, NOx, HNO3 and PAN near dairy farms were significantly underestimated in the model. Negative biases also exist for O3 and HNO3 near oil fields, suggesting larger uncertainties associated with these emission sources. While the model simulated the total NOy mixing ratios reasonably well, the prediction for partitioning between individual compounds showed larger uncertainties in the model simulation. Although the fire emissions inventory was updated to include the latest emissions estimates and speciation profiles, our model shows limited improvement in simulating the enhancement of O3, CO, and PAN under fire impact as

  9. High-sensitivity C-reactive protein, lipoprotein-related phospholipase A2, and acute ischemic stroke

    Directory of Open Access Journals (Sweden)

    Kara H

    2014-08-01

    Full Text Available Hasan Kara,1 Murat Akinci,1 Selim Degirmenci,1 Aysegul Bayir,1 Ahmet Ak,1 Alaaddin Nayman,2 Ali Unlu,3 Fikret Akyurek,3 Mesut Sivri2 1Department of Emergency Medicine, 2Department of Radiology, 3Department of Biochemistry, Faculty of Medicine, Selçuk University, Konya, Turkey Background: Serum biomarkers may be useful for early diagnosis of acute ischemic stroke, exclusion of other diseases that may mimic stroke, and prediction of infarct volume. We evaluated serum high-sensitivity C-reactive protein (hs-CRP and lipoprotein-related phospholipase A2 (Lp-PLA2 in patients who had acute ischemic stroke.Methods: In 200 patients who presented to an emergency service (acute ischemic stroke, 102 patients; control with no stroke, 98 patients, stroke patients were evaluated with the Canadian neurological scale and diffusion-weighted magnetic resonance imaging, and all patients were evaluated with the Glasgow coma scale and their serum hs-CRP level and Lp-PLA2 activity were assessed. The volume of stroke lesions was calculated from magnetic resonance images.Results: Patients who had stroke had higher mean serum hs-CRP level (stroke, 7±6 mg/dL; ­control, mean ± standard deviation 1±1 mg/dL; P≤0.001 and Lp-PLA2 activity (stroke, mean ± standard deviation 113±86 nmol/min/mL; control, mean ± standard deviation 103±50 nmol/min/mL; P≤0.001 than control patients who did not have stroke. The mean hs-CRP level and Lp-PLA2 activity were higher in patients who had greater stroke severity (lower Canadian neurological scale score and were higher in patients who had larger volume strokes. Conclusion: Higher hs-CRP level and Lp-PLA2 activity are significantly associated with more severe neurologic impairment and larger infarct size in patients who have acute ischemic stroke. These biomarkers may be useful for rapid diagnosis and prediction of ischemic tissue volume in the early stage of ischemic stroke. These findings may be important for health

  10. A comparison of osteoprotegerin with adiponectin and high-sensitivity C-reactive protein (hsCRP) as a marker for insulin resistance.

    LENUS (Irish Health Repository)

    O'Sullivan, Eoin P

    2013-01-01

    Insulin resistance (IR) is associated with low adiponectin and elevated high sensitivity C-reactive protein (hsCRP). Osteoprotegerin (OPG) has been shown to be elevated in type 2 diabetes, but whether it reflects underlying IR is unclear. We aimed to compare the ability of serum OPG with adiponectin and hsCRP to act as a marker for IR in individuals with normal and abnormal glucose tolerance.

  11. Chemical and mineralogical characterization of highly and less reactive coal from Northern Natal and Venda-Pafuri coalfields in South Africa

    Science.gov (United States)

    Kataka, M. O.; Matiane, A. R.; Odhiambo, B. D. O.

    2018-01-01

    Spontaneous combustion of coal is a major hazard associated with the coal mining industry over centuries. It also a major cause of underground fires in South African collieries and in opencast operations, spoil heaps and stockpiles. Spontaneous combustion incidents are manifested in all major aspects of coal mining namely, underground mining, surface mining, including during sea-borne transportation, storage and waste disposal. Previous studies indicate that there are various factors (both intrinsic and extrinsic) that influence the spontaneous combustion of coals. This paper characterizes highly reactive coal from the Vryheid coalfields and less reactive coal from at Venda-Pafuri coalfield, to identify and delineate some intrinsic coal parameters that are considered to be most critical in terms of heat 'generation' and relationships between the two coals types by tracing their similarities and differences in their spontaneous combustion parameters. Various tests were carried out to characterize these coals in terms of their intrinsic properties, namely: ultimate, proximate, petrographic analysis and Glasser spontaneous tests. The ultimate and proximate analysis showed that spontaneous coal has high contents of carbon, oxygen, and volatile matter as compared to non-spontaneous coal, making it more susceptible to spontaneous combustion. Non-spontaneous coal has higher ash content than the spontaneous coal. Furthermore, the petrographic analysis showed that spontaneous coal has high total reactivity compared to the non-spontaneous coal. Results from Glasser spontaneous test indicate that spontaneous coal absorbs more oxygen than non-spontaneous coal, which explains why spontaneous coal is more susceptible to spontaneous combustion. High reactive coal has low values of critical self-heating temperature (CSHT), indicating that this coal has potential of spontaneous ignition.

  12. Comparing the Effect of Endurance and High Intensity Interval Trainings on Levels of Chemerin and Protein of C-reactive Plasma in Obese Children

    OpenAIRE

    Morteza Salimi Avan sar; Abdolsaleh Zar

    2017-01-01

    Abstract Background: The prevalence of obesity among children is alarmingly rising. Obesity in a chronical inflammatory condition accompanies with inflammatory markers such as Chemerin and CRP; therefore, the aim of this following study is to compare the affection of Endurance & High Intensity Interval Trainings on levels of Chemerin & Protein of C-reactive plasma in obese children. Materials and Methods: This experimentation included 21 obese children (average weight 61.46±2.5 kg and B...

  13. Effect of Compound Danshen Dripping Pill on circadian blood pressure, high sensitive C reactive protein and cardiac function in patients with non dipper hypertension

    OpenAIRE

    He, Zhi-Wei; Liu, Hui-qin

    2014-01-01

    Objective: To investigate the effect of Compound Danshen Dripping Pill on circadian blood pressure, high sensitive C reactive protein and cardiac function in patients with non dipper hypertension. Methods: According to ABPM nocturnal blood pressure decline rate < 10%, select 178 patients whose systolic pressure and diastolic pressure meet the standards, 88 cases were divided into treatment group, and the rest 90 cases were in control group. All patients were having the levoamlodipine malea...

  14. Association Of Serum Pentraxin-3 And High-Sensitivity C-Reactive Protein With The Extent Of Coronary Stenosis In Patients Undergoing Coronary Angiography

    Directory of Open Access Journals (Sweden)

    Vuković-Dejanović Vesna

    2015-10-01

    Full Text Available Background: We compared factors of inflammation – high sensitivity C-reactive protein (hsCRP and pentraxin-3 (PTX3, and we explored their relationship with coronary artery disease (CAD. Also, we tested the usefulness of hsCRP and PTX3 in the risk assessment of coronary stenosis development and the diagnostic ability of these biomarkers to detect disease severity.

  15. Association between Resting Heart Rate and Inflammatory Markers (White Blood Cell Count and High-Sensitivity C-Reactive Protein) in Healthy Korean People.

    Science.gov (United States)

    Park, Woo-Chul; Seo, Inho; Kim, Shin-Hye; Lee, Yong-Jae; Ahn, Song Vogue

    2017-01-01

    Inflammation is an important underlying mechanism in the pathogenesis of atherosclerosis, and an elevated resting heart rate underlies the process of atherosclerotic plaque formation. We hypothesized an association between resting heart rate and subclinical inflammation. Resting heart rate was recorded at baseline in the KoGES-ARIRANG (Korean Genome and Epidemiology Study on Atherosclerosis Risk of Rural Areas in the Korean General Population) cohort study, and was then divided into quartiles. Subclinical inflammation was measured by white blood cell count and high-sensitivity C-reactive protein. We used progressively adjusted regression models with terms for muscle mass, body fat proportion, and adiponectin in the fully adjusted models. We examined inflammatory markers as both continuous and categorical variables, using the clinical cut point of the highest quartile of white blood cell count (≥7,900/mm(3)) and ≥3 mg/dL for high-sensitivity C-reactive protein. Participants had a mean age of 56.3±8.1 years and a mean resting heart rate of 71.4±10.7 beats/min; 39.1% were men. In a fully adjusted model, an increased resting heart rate was significantly associated with a higher white blood cell count and higher levels of high-sensitivity C-reactive protein in both continuous (P for trend heart rate is associated with a higher level of subclinical inflammation among healthy Korean people.

  16. High sensitive and high temporal and spatial resolved image of reactive species in atmospheric pressure surface discharge reactor by laser induced fluorescence

    Science.gov (United States)

    Gao, Liang; Feng, Chun-Lei; Wang, Zhi-Wei; Ding, Hongbin

    2017-05-01

    The current paucity of spatial and temporal characterization of reactive oxygen and nitrogen species (RONS) concentration has been a major hurdle to the advancement and clinical translation of low temperature atmospheric plasmas. In this study, an advanced laser induced fluorescence (LIF) system has been developed to be an effective antibacterial surface discharge reactor for the diagnosis of RONS, where the highest spatial and temporal resolution of the LIF system has been achieved to ˜100 μm scale and ˜20 ns scale, respectively. Measurements on an oxidative OH radical have been carried out as typical RONS for the benchmark of the whole LIF system, where absolute number density calibration has been performed on the basis of the laser Rayleigh scattering method. Requirements for pixel resolved spatial distribution and outer plasma region detection become challenging tasks due to the low RONS concentration (˜ppb level) and strong interference, especially the discharge induced emission and pulsed laser induced stray light. In order to design the highly sensitive LIF system, a self-developed fluorescence telescope, the optimization of high precision synchronization among a tunable pulsed laser, a surface discharge generator, intensified Charge Coupled Device (iCCD) camera, and an oscilloscope have been performed. Moreover, an image BOXCAR approach has been developed to remarkably improve the sensitivity of the whole LIF system by optimizing spatial and temporal gating functions via both hardware and software, which has been integrated into our automatic control and data acquisition system on the LabVIEW platform. In addition, a reciprocation averaging measurement has been applied to verify the accuracy of the whole LIF detecting system, indicating the relative standard deviation of ˜3%.

  17. Chemical Reactivity Test (CRT)

    Energy Technology Data Exchange (ETDEWEB)

    Zaka, F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-12-13

    The Chemical Reactivity Test (CRT) is used to determine the thermal stability of High Explosives (HEs) and chemical compatibility between (HEs) and alien materials. The CRT is one of the small-scale safety tests performed on HE at the High Explosives Applications Facility (HEAF).

  18. High Intratumoral Stromal Content Defines Reactive Breast Cancer as a Low-risk Breast Cancer Subtype | Office of Cancer Genomics

    Science.gov (United States)

    Improved biomarker tests are required to minimize overdiagnosis and overtreatment of breast cancers. A number of pathologic criteria have been established to differentiate indolent or aggressive behavior, such as Nottingham grade of cancer cells. However, the effects of the tumor microenvironment on patient outcomes have not been integrated into pathologic criteria. In the current study, the Reactive subtype of breast cancer, identified by reverse-phase protein arrays, was demonstrated to indicate a favorable outcome.

  19. High-throughput Characterization of HIV-1 Reservoir Reactivation Using a Single-Cell-in-Droplet PCR Assay

    Directory of Open Access Journals (Sweden)

    Robert W. Yucha

    2017-06-01

    Full Text Available Reactivation of latent viral reservoirs is on the forefront of HIV-1 eradication research. However, it is unknown if latency reversing agents (LRAs increase the level of viral transcription from cells producing HIV RNA or harboring transcriptionally-inactive (latent infection. We therefore developed a microfluidic single-cell-in-droplet (scdPCR assay to directly measure the number of CD4+ T cells that produce unspliced (usRNA and multiply spliced (msRNA following ex vivo latency reversal with either an histone deacetylase inhibitor (romidepsin or T cell receptor (TCR stimulation. Detection of HIV-1 transcriptional activity can also be performed on hundreds of thousands of CD4+ T-cells in a single experiment. The scdPCR method was then applied to CD4+ T cells obtained from HIV-1-infected individuals on antiretroviral therapy. Overall, our results suggest that effects of LRAs on HIV-1 reactivation may be heterogeneous—increasing transcription from active cells in some cases and increasing the number of transcriptionally active cells in others. Genomic DNA and human mRNA isolated from HIV-1 reactivated cells could also be detected and quantified from individual cells. As a result, our assay has the potential to provide needed insight into various reservoir eradication strategies.

  20. Flexible modified candle burnup scheme based long life Pb-Bi cooled fast reactor with natural uranium as fuel cycle input employing coupled core

    Energy Technology Data Exchange (ETDEWEB)

    Su' ud, Zaki; SNM, Rida [Physics Dept., ITB, Jl. Ganesha 10, Bandung, West Java 40132 (Indonesia); Sekimoto, Hiroshi [Tokyo Inst. of Technology (Japan)

    2009-06-15

    Nuclear fuel enrichment and nuclear fuel reprocessing are two very sensitive issues related to the nuclear nonproliferation in the world especially when it is carried out in the developing countries. However without these two processes (at least one of them) the optimal nuclear energy utilization is difficult to be achieved. In this study, conceptual design of long life Pb-Bi cooled fast reactors which can be continuously operated by only supplying natural uranium without fuel enrichment plant or fuel reprocessing plant is performed. Therefore using this type of nuclear power plants optimum nuclear energy utilization including in developing countries can be easily conducted without the problem of nuclear proliferation. In this study conceptual design study of Pb-Bi cooled fast reactors which fuel cycle need only natural uranium input has been performed. In this case CANDLE1-2 burn-up strategy is slightly modified by introducing discreet regions. In this design the reactor cores are subdivided into several parts with the same volume in the axial directions. The natural uranium is initially put in region 1, after one cycle of 10 years of burn-up it is shifted to region 2 and the region 1 is filled by fresh natural uranium fuel. This concept is basically applied to all regions, i.e. shifted the core of I'th region into I+1 region after the end of 10 years burn-up cycle. To increase the criticality we adopt tandem of dual modified CANDLE cores and coupled them together. The calculation is performed using SRAC code system (SRAC-CITATION system). At the beginning we assume the power density level in each region and then we perform the burn-up calculation using the assumed data. The burn-up calculation is performed using cell burn-up in SRAC code which then give eight energy group macroscopic cross section data to be used in two dimensional R-Z geometry multi groups diffusion calculation. The average power density in each region resulted from the diffusion

  1. Linking complex geochemical and hydrological processes using streamlines for highly-resolved, reactive transport CO2 leakage scenarios

    Science.gov (United States)

    Atchley, A. L.; Maxwell, R. M.; Navarre-Sitchler, A. K.

    2011-12-01

    Simulating reactive transport and geochemical processes over large, finely resolved domains i