Science.gov

Sample records for mcnp-based depletion codes

  1. ALEPH2 - A general purpose Monte Carlo depletion code

    SciTech Connect

    Stankovskiy, A.; Van Den Eynde, G.; Baeten, P.; Trakas, C.; Demy, P. M.; Villatte, L.

    2012-07-01

    The Monte-Carlo burn-up code ALEPH is being developed at SCK-CEN since 2004. A previous version of the code implemented the coupling between the Monte Carlo transport (any version of MCNP or MCNPX) and the ' deterministic' depletion code ORIGEN-2.2 but had important deficiencies in nuclear data treatment and limitations inherent to ORIGEN-2.2. A new version of the code, ALEPH2, has several unique features making it outstanding among other depletion codes. The most important feature is full data consistency between steady-state Monte Carlo and time-dependent depletion calculations. The last generation general-purpose nuclear data libraries (JEFF-3.1.1, ENDF/B-VII and JENDL-4) are fully implemented, including special purpose activation, spontaneous fission, fission product yield and radioactive decay data. The built-in depletion algorithm allows to eliminate the uncertainties associated with obtaining the time-dependent nuclide concentrations. A predictor-corrector mechanism, calculation of nuclear heating, calculation of decay heat, decay neutron sources are available as well. The validation of the code on the results of REBUS experimental program has been performed. The ALEPH2 has shown better agreement with measured data than other depletion codes. (authors)

  2. SMITHERS: An object-oriented modular mapping methodology for MCNP-based neutronic–thermal hydraulic multiphysics

    SciTech Connect

    Richard, Joshua; Galloway, Jack; Fensin, Michael; Trellue, Holly

    2015-04-04

    A novel object-oriented modular mapping methodology for externally coupled neutronics–thermal hydraulics multiphysics simulations was developed. The Simulator using MCNP with Integrated Thermal-Hydraulics for Exploratory Reactor Studies (SMITHERS) code performs on-the-fly mapping of material-wise power distribution tallies implemented by MCNP-based neutron transport/depletion solvers for use in estimating coolant temperature and density distributions with a separate thermal-hydraulic solver. The key development of SMITHERS is that it reconstructs the hierarchical geometry structure of the material-wise power generation tallies from the depletion solver automatically, with only a modicum of additional information required from the user. In addition, it performs the basis mapping from the combinatorial geometry of the depletion solver to the required geometry of the thermal-hydraulic solver in a generalizable manner, such that it can transparently accommodate varying levels of thermal-hydraulic solver geometric fidelity, from the nodal geometry of multi-channel analysis solvers to the pin-cell level of discretization for sub-channel analysis solvers.

  3. SMITHERS: An object-oriented modular mapping methodology for MCNP-based neutronic–thermal hydraulic multiphysics

    DOE PAGESBeta

    Richard, Joshua; Galloway, Jack; Fensin, Michael; Trellue, Holly

    2015-04-04

    A novel object-oriented modular mapping methodology for externally coupled neutronics–thermal hydraulics multiphysics simulations was developed. The Simulator using MCNP with Integrated Thermal-Hydraulics for Exploratory Reactor Studies (SMITHERS) code performs on-the-fly mapping of material-wise power distribution tallies implemented by MCNP-based neutron transport/depletion solvers for use in estimating coolant temperature and density distributions with a separate thermal-hydraulic solver. The key development of SMITHERS is that it reconstructs the hierarchical geometry structure of the material-wise power generation tallies from the depletion solver automatically, with only a modicum of additional information required from the user. In addition, it performs the basis mapping from themore » combinatorial geometry of the depletion solver to the required geometry of the thermal-hydraulic solver in a generalizable manner, such that it can transparently accommodate varying levels of thermal-hydraulic solver geometric fidelity, from the nodal geometry of multi-channel analysis solvers to the pin-cell level of discretization for sub-channel analysis solvers.« less

  4. VESTA 2.1.5 - Monte Carlo Depletion Interface Code; AURORA 1.0.0 - Depletion Analysis Tool.

    SciTech Connect

    HAECK, WIM

    2013-03-21

    Version 01 RSICC is authorized to distribute VESTA 2.1.5 for research and education purposes only. Requesters from NEA Data Bank member countries are advised to order VESTA 2.1.5 from the NEA Data Bank. Non-commercial and non-profit users from other OECD member countries (specifically Canada and the United States) may order VESTA 2.1.5 from RSICC. Users from non-OECD member countries and all commercial requesters are advised to contact the IRSN. VESTA is a Monte Carlo depletion interface code that is currently under development at IRSN (France). From its inception, VESTA is intended to be a “generic” interface code so that it will ultimately be capable of using any Monte-Carlo code or depletion module and that can be completely tailored to the user’s needs on practically all aspects of the code. For the current version, VESTA allows for the use of any version of MCNP(X) as the transport module and ORIGEN 2.2 or the built in PHOENIX module as the depletion module. A short overview of the main features of this version of the code is detailed in the Abstract.

  5. The new MCNP6 depletion capability

    SciTech Connect

    Fensin, M. L.; James, M. R.; Hendricks, J. S.; Goorley, J. T.

    2012-07-01

    The first MCNP based in-line Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology. (authors)

  6. The New MCNP6 Depletion Capability

    SciTech Connect

    Fensin, Michael Lorne; James, Michael R.; Hendricks, John S.; Goorley, John T.

    2012-06-19

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. Both the MCNP5 and MCNPX codes have historically provided a successful combinatorial geometry based, continuous energy, Monte Carlo radiation transport solution for advanced reactor modeling and simulation. However, due to separate development pathways, useful simulation capabilities were dispersed between both codes and not unified in a single technology. MCNP6, the next evolution in the MCNP suite of codes, now combines the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. We describe here the new capabilities of the MCNP6 depletion code dating from the official RSICC release MCNPX 2.6.0, reported previously, to the now current state of MCNP6. NEA/OECD benchmark results are also reported. The MCNP6 depletion capability enhancements beyond MCNPX 2.6.0 reported here include: (1) new performance enhancing parallel architecture that implements both shared and distributed memory constructs; (2) enhanced memory management that maximizes calculation fidelity; and (3) improved burnup physics for better nuclide prediction. MCNP6 depletion enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code. The enhancements described here help provide a powerful capability as well as dictate a path forward for future development to improve the usefulness of the technology.

  7. VESTA 2.1.5 - Monte Carlo Depletion Interface Code; AURORA 1.0.0 - Depletion Analysis Tool.

    Energy Science and Technology Software Center (ESTSC)

    2013-03-21

    Version 01 RSICC is authorized to distribute VESTA 2.1.5 for research and education purposes only. Requesters from NEA Data Bank member countries are advised to order VESTA 2.1.5 from the NEA Data Bank. Non-commercial and non-profit users from other OECD member countries (specifically Canada and the United States) may order VESTA 2.1.5 from RSICC. Users from non-OECD member countries and all commercial requesters are advised to contact the IRSN. VESTA is a Monte Carlo depletionmore » interface code that is currently under development at IRSN (France). From its inception, VESTA is intended to be a “generic” interface code so that it will ultimately be capable of using any Monte-Carlo code or depletion module and that can be completely tailored to the user’s needs on practically all aspects of the code. For the current version, VESTA allows for the use of any version of MCNP(X) as the transport module and ORIGEN 2.2 or the built in PHOENIX module as the depletion module. A short overview of the main features of this version of the code is detailed in the Abstract.« less

  8. ORIGEN2: a revised and updated version of the Oak Ridge isotope generation and depletion code

    SciTech Connect

    Croff, A.G.

    1980-07-01

    ORIGEN2 is a versatile point depletion and decay computer code for use in simulating nuclear fuel cycles and calculating the nuclide compositions of materials contained therein. This code represents a revision and update of the original ORIGEN computer code which has been distributed world-wide beginning in the early 1970s. The purpose of this report is to give a summary description of a revised and updated version of the original ORIGEN computer code, which has been designated ORIGEN2. A detailed description of the computer code ORIGEN2 is presented. The methods used by ORIGEN2 to solve the nuclear depletion and decay equations are included. Input information necessary to use ORIGEN2 that has not been documented in supporting reports is documented.

  9. DANDE: a linked code system for core neutronics/depletion analysis

    SciTech Connect

    LaBauve, R.J.; England, T.R.; George, D.C.; MacFarlane, R.E.; Wilson, W.B.

    1985-06-01

    This report describes DANDE - a modular neutronics, depletion code system for reactor analysis. It consists of nuclear data processing, core physics, and fuel depletion modules, and allows one to use diffusion and transport methods interchangeably in core neutronics calculations. This latter capability is especially important in the design of small modular cores. Additional unique features include the capability of updating the nuclear data file during a calculation; a detailed treatment of depletion, burnable poisons as well as fuel; and the ability to make geometric changes such as control rod repositioning and fuel relocation in the course of a calculation. The detailed treatment of reactor fuel burnup, fission-product creation and decay, as well as inventories of higher-order actinides is a necessity when predicting the behavior of reactor fuel under increased burn conditions. The operation of the code system is made clear in this report by following a sample problem.

  10. FORIG: a modification of the ORIGEN2 isotope-generation and depletion code for fusion problems

    SciTech Connect

    Blink, J.A.

    1982-03-03

    This report describes how to use the FORIG computer code to solve isotope-generation and depletion problems in fusion and fission reactors. FORIG is an adaptation of ORIGEN2 to run on a Cray-1 computer, and to accept more extensive activation cross sections.

  11. Validation of depletion codes for burnup credit evaluation of LWR assemblies

    SciTech Connect

    Ranta-aho, A.

    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)

  12. Improvements of MCOR: A Monte Carlo depletion code system for fuel assembly reference calculations

    SciTech Connect

    Tippayakul, C.; Ivanov, K.; Misu, S.

    2006-07-01

    This paper presents the improvements of MCOR, a Monte Carlo depletion code system for fuel assembly reference calculations. The improvements of MCOR were initiated by the cooperation between the Penn State Univ. and AREVA NP to enhance the original Penn State Univ. MCOR version in order to be used as a new Monte Carlo depletion analysis tool. Essentially, a new depletion module using KORIGEN is utilized to replace the existing ORIGEN-S depletion module in MCOR. Furthermore, the online burnup cross section generation by the Monte Carlo calculation is implemented in the improved version instead of using the burnup cross section library pre-generated by a transport code. Other code features have also been added to make the new MCOR version easier to use. This paper, in addition, presents the result comparisons of the original and the improved MCOR versions against CASMO-4 and OCTOPUS. It was observed in the comparisons that there were quite significant improvements of the results in terms of k{sub inf}, fission rate distributions and isotopic contents. (authors)

  13. The Modeling of Advanced BWR Fuel Designs with the NRC Fuel Depletion Codes PARCS/PATHS

    DOE PAGESBeta

    Ward, Andrew; Downar, Thomas J.; Xu, Y.; March-Leuba, Jose A; Thurston, Carl; Hudson, Nathanael H.; Ireland, A.; Wysocki, A.

    2015-04-22

    The PATHS (PARCS Advanced Thermal Hydraulic Solver) code was developed at the University of Michigan in support of U.S. Nuclear Regulatory Commission research to solve the steady-state, two-phase, thermal-hydraulic equations for a boiling water reactor (BWR) and to provide thermal-hydraulic feedback for BWR depletion calculations with the neutronics code PARCS (Purdue Advanced Reactor Core Simulator). The simplified solution methodology, including a three-equation drift flux formulation and an optimized iteration scheme, yields very fast run times in comparison to conventional thermal-hydraulic systems codes used in the industry, while still retaining sufficient accuracy for applications such as BWR depletion calculations. Lastly, themore » capability to model advanced BWR fuel designs with part-length fuel rods and heterogeneous axial channel flow geometry has been implemented in PATHS, and the code has been validated against previously benchmarked advanced core simulators as well as BWR plant and experimental data. We describe the modifications to the codes and the results of the validation in this paper.« less

  14. The Modeling of Advanced BWR Fuel Designs with the NRC Fuel Depletion Codes PARCS/PATHS

    SciTech Connect

    Ward, Andrew; Downar, Thomas J.; Xu, Y.; March-Leuba, Jose A; Thurston, Carl; Hudson, Nathanael H.; Ireland, A.; Wysocki, A.

    2015-04-22

    The PATHS (PARCS Advanced Thermal Hydraulic Solver) code was developed at the University of Michigan in support of U.S. Nuclear Regulatory Commission research to solve the steady-state, two-phase, thermal-hydraulic equations for a boiling water reactor (BWR) and to provide thermal-hydraulic feedback for BWR depletion calculations with the neutronics code PARCS (Purdue Advanced Reactor Core Simulator). The simplified solution methodology, including a three-equation drift flux formulation and an optimized iteration scheme, yields very fast run times in comparison to conventional thermal-hydraulic systems codes used in the industry, while still retaining sufficient accuracy for applications such as BWR depletion calculations. Lastly, the capability to model advanced BWR fuel designs with part-length fuel rods and heterogeneous axial channel flow geometry has been implemented in PATHS, and the code has been validated against previously benchmarked advanced core simulators as well as BWR plant and experimental data. We describe the modifications to the codes and the results of the validation in this paper.

  15. Probabilistic approach for decay heat uncertainty estimation using URANIE platform and MENDEL depletion code

    NASA Astrophysics Data System (ADS)

    Tsilanizara, A.; Gilardi, N.; Huynh, T. D.; Jouanne, C.; Lahaye, S.; Martinez, J. M.; Diop, C. M.

    2014-06-01

    The knowledge of the decay heat quantity and the associated uncertainties are important issues for the safety of nuclear facilities. Many codes are available to estimate the decay heat. ORIGEN, FISPACT, DARWIN/PEPIN2 are part of them. MENDEL is a new depletion code developed at CEA, with new software architecture, devoted to the calculation of physical quantities related to fuel cycle studies, in particular decay heat. The purpose of this paper is to present a probabilistic approach to assess decay heat uncertainty due to the decay data uncertainties from nuclear data evaluation like JEFF-3.1.1 or ENDF/B-VII.1. This probabilistic approach is based both on MENDEL code and URANIE software which is a CEA uncertainty analysis platform. As preliminary applications, single thermal fission of uranium 235, plutonium 239 and PWR UOx spent fuel cell are investigated.

  16. ORPHEE research reactor: 3D core depletion calculation using Monte-Carlo code TRIPOLI-4®

    NASA Astrophysics Data System (ADS)

    Damian, F.; Brun, E.

    2014-06-01

    ORPHEE is a research reactor located at CEA Saclay. It aims at producing neutron beams for experiments. This is a pool-type reactor (heavy water), and the core is cooled by light water. Its thermal power is 14 MW. ORPHEE core is 90 cm height and has a cross section of 27x27 cm2. It is loaded with eight fuel assemblies characterized by a various number of fuel plates. The fuel plate is composed of aluminium and High Enriched Uranium (HEU). It is a once through core with a fuel cycle length of approximately 100 Equivalent Full Power Days (EFPD) and with a maximum burnup of 40%. Various analyses under progress at CEA concern the determination of the core neutronic parameters during irradiation. Taking into consideration the geometrical complexity of the core and the quasi absence of thermal feedback for nominal operation, the 3D core depletion calculations are performed using the Monte-Carlo code TRIPOLI-4® [1,2,3]. A preliminary validation of the depletion calculation was performed on a 2D core configuration by comparison with the deterministic transport code APOLLO2 [4]. The analysis showed the reliability of TRIPOLI-4® to calculate a complex core configuration using a large number of depleting regions with a high level of confidence.

  17. KRAM, A lattice physics code for modeling the detailed depletion of gadolinia isotopes in BWR lattice designs

    SciTech Connect

    Knott, D.; Baratta, A. )

    1990-01-01

    Lattice physics codes are used to deplete the burnable isotopes present in each lattice design, calculate the buildup of fission products, and generate the few-group cross-section data needed by the various nodal simulator codes. Normally, the detailed depletion of gadolinia isotopes is performed outside the lattice physics code in a one-dimensional environment using an onion-skin model, such as the method used in MICBURN. Results from the onion-skin depletion, in the form of effective microscopic absorption cross sections for the gadolinia, are then used by the lattice physics code during the lattice-depletion analysis. The reactivity of the lattice at any point in the cycle depends to a great extent on the amount of gadolinia present. In an attempt to improve the modeling of gadolinia depletion from fresh boiling water reactor (BWR) fuel designs, the electric Power Research Institute (EPRI) lattice-physics code CPM-2 has been modified extensively. In this paper, the modified code KRAM is described, and results from various lattice-depletion analyses are discussed in comparison with results from standard CPM-2 and CASMO-2 analyses.

  18. MCNP-based computational model for the Leksell Gamma Knife

    SciTech Connect

    Trnka, Jiri; Novotny, Josef Jr.; Kluson, Jaroslav

    2007-01-15

    We have focused on the usage of MCNP code for calculation of Gamma Knife radiation field parameters with a homogenous polystyrene phantom. We have investigated several parameters of the Leksell Gamma Knife radiation field and compared the results with other studies based on EGS4 and PENELOPE code as well as the Leksell Gamma Knife treatment planning system Leksell GammaPlan (LGP). The current model describes all 201 radiation beams together and simulates all the sources in the same time. Within each beam, it considers the technical construction of the source, the source holder, collimator system, the spherical phantom, and surrounding material. We have calculated output factors for various sizes of scoring volumes, relative dose distributions along basic planes including linear dose profiles, integral doses in various volumes, and differential dose volume histograms. All the parameters have been calculated for each collimator size and for the isocentric configuration of the phantom. We have found the calculated output factors to be in agreement with other authors' works except the case of 4 mm collimator size, where averaging over the scoring volume and statistical uncertainties strongly influences the calculated results. In general, all the results are dependent on the choice of the scoring volume. The calculated linear dose profiles and relative dose distributions also match independent studies and the Leksell GammaPlan, but care must be taken about the fluctuations within the plateau, which can influence the normalization, and accuracy in determining the isocenter position, which is important for comparing different dose profiles. The calculated differential dose volume histograms and integral doses have been compared with data provided by the Leksell GammaPlan. The dose volume histograms are in good agreement as well as integral doses calculated in small calculation matrix volumes. However, deviations in integral doses up to 50% can be observed for large

  19. MCNP-based computational model for the Leksell gamma knife.

    PubMed

    Trnka, Jiri; Novotny, Josef; Kluson, Jaroslav

    2007-01-01

    We have focused on the usage of MCNP code for calculation of Gamma Knife radiation field parameters with a homogenous polystyrene phantom. We have investigated several parameters of the Leksell Gamma Knife radiation field and compared the results with other studies based on EGS4 and PENELOPE code as well as the Leksell Gamma Knife treatment planning system Leksell GammaPlan (LGP). The current model describes all 201 radiation beams together and simulates all the sources in the same time. Within each beam, it considers the technical construction of the source, the source holder, collimator system, the spherical phantom, and surrounding material. We have calculated output factors for various sizes of scoring volumes, relative dose distributions along basic planes including linear dose profiles, integral doses in various volumes, and differential dose volume histograms. All the parameters have been calculated for each collimator size and for the isocentric configuration of the phantom. We have found the calculated output factors to be in agreement with other authors' works except the case of 4 mm collimator size, where averaging over the scoring volume and statistical uncertainties strongly influences the calculated results. In general, all the results are dependent on the choice of the scoring volume. The calculated linear dose profiles and relative dose distributions also match independent studies and the Leksell GammaPlan, but care must be taken about the fluctuations within the plateau, which can influence the normalization, and accuracy in determining the isocenter position, which is important for comparing different dose profiles. The calculated differential dose volume histograms and integral doses have been compared with data provided by the Leksell GammaPlan. The dose volume histograms are in good agreement as well as integral doses calculated in small calculation matrix volumes. However, deviations in integral doses up to 50% can be observed for large

  20. A MCNP-based calibration method and a voxel phantom for in vivo monitoring of 241Am in skull

    NASA Astrophysics Data System (ADS)

    Moraleda, M.; Gómez-Ros, J. M.; López, M. A.; Navarro, T.; Navarro, J. F.

    2004-07-01

    Whole body counter (WBC) facilities are currently used for assessment of internal radionuclide body burdens by directly measuring the radiation emitted from the body. Previous calibration of the detection devices requires the use of specific anthropomorphic phantoms. This paper describes the MCNP-based Monte Carlo technique developed for calibration of the germanium detectors (Canberra LE Ge) used in the CIEMAT WBC for in vivo measurements of 241Am in skull. The proposed method can also be applied for in vivo counting of different radionuclides distributed in other anatomical regions as well as for other detectors. A computer software was developed to automatically generate the input files for the MCNP code starting from any segmented human anatomy data. A specific model of a human head for the assessment of 241Am was built based on the tomographic phantom VOXELMAN of Yale University. The germanium detectors were carefully modelled from data provided by the manufacturer. This numerical technique has been applied to investigate the best counting geometry and the uncertainty due to improper positioning of the detectors.

  1. Development of Depletion Code Surrogate Models for Uncertainty Propagation in Scenario Studies

    NASA Astrophysics Data System (ADS)

    Krivtchik, Guillaume; Coquelet-Pascal, Christine; Blaise, Patrick; Garzenne, Claude; Le Mer, Joël; Freynet, David

    2014-06-01

    The result of transition scenario studies, which enable the comparison of different options of the reactor fleet evolution and management of the future fuel cycle materials, allow to perform technical and economic feasibility studies. The COSI code is developed by CEA and used to perform scenario calculations. It allows to model any fuel type, reactor fleet, fuel facility, and permits the tracking of U, Pu, minor actinides and fission products nuclides on a large time scale. COSI is coupled with the CESAR code which performs the depletion calculations based on one-group cross-section libraries and nuclear data. Different types of uncertainties have an impact on scenario studies: nuclear data and scenario assumptions. Therefore, it is necessary to evaluate their impact on the major scenario results. The methodology adopted to propagate these uncertainties throughout the scenario calculations is a stochastic approach. Considering the amount of inputs to be sampled in order to perform a stochastic calculation of the propagated uncertainty, it appears necessary to reduce the calculation time. Given that evolution calculations represent approximately 95% of the total scenario simulation time, an optimization can be done, with the development and implementation of a surrogate models library of CESAR in COSI. The input parameters of CESAR are sampled with URANIE, the CEA uncertainty platform, and for every sample, the isotopic composition after evolution evaluated with CESAR is stored. Then statistical analysis of the input and output tables allow to model the behavior of CESAR on each CESAR library, i.e. building a surrogate model. Several quality tests are performed on each surrogate model to insure the prediction power is satisfying. Afterward, a new routine implemented in COSI reads these surrogate models and using them in replacement of CESAR calculations. A preliminary study of the calculation time gain shows that the use of surrogate models allows stochastic

  2. FORIG: a computer code for calculating radionuclide generation and depletion in fusion and fission reactors. User's manual

    SciTech Connect

    Blink, J.A.

    1985-03-01

    In this manual we describe the use of the FORIG computer code to solve isotope-generation and depletion problems in fusion and fission reactors. FORIG runs on a Cray-1 computer and accepts more extensive activation cross sections than ORIGEN2 from which it was adapted. This report is an updated and a combined version of the previous ORIGEN2 and FORIG manuals. 7 refs., 15 figs., 13 tabs.

  3. Performance upgrades to the MCNP6 burnup capability for large scale depletion calculations

    DOE PAGESBeta

    Fensin, M. L.; Galloway, J. D.; James, M. R.

    2015-04-11

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. With the merger of MCNPX and MCNP5, MCNP6 combined the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. The new MCNP6 depletion capability was first showcased at the International Congress for Advancements in Nuclear Power Plants (ICAPP) meeting in 2012. At that conference the new capabilities addressed included the combined distributive and shared memory parallel architecture for the burnup capability, improved memory management, physics enhancements, and newmore » predictability as compared to the H.B Robinson Benchmark. At Los Alamos National Laboratory, a special purpose cluster named “tebow,” was constructed such to maximize available RAM per CPU, as well as leveraging swap space with solid state hard drives, to allow larger scale depletion calculations (allowing for significantly more burnable regions than previously examined). As the MCNP6 burnup capability was scaled to larger numbers of burnable regions, a noticeable slowdown was realized.This paper details two specific computational performance strategies for improving calculation speedup: (1) retrieving cross sections during transport; and (2) tallying mechanisms specific to burnup in MCNP. To combat this slowdown new performance upgrades were developed and integrated into MCNP6 1.2.« less

  4. Performance upgrades to the MCNP6 burnup capability for large scale depletion calculations

    SciTech Connect

    Fensin, M. L.; Galloway, J. D.; James, M. R.

    2015-04-11

    The first MCNP based inline Monte Carlo depletion capability was officially released from the Radiation Safety Information and Computational Center as MCNPX 2.6.0. With the merger of MCNPX and MCNP5, MCNP6 combined the capability of both simulation tools, as well as providing new advanced technology, in a single radiation transport code. The new MCNP6 depletion capability was first showcased at the International Congress for Advancements in Nuclear Power Plants (ICAPP) meeting in 2012. At that conference the new capabilities addressed included the combined distributive and shared memory parallel architecture for the burnup capability, improved memory management, physics enhancements, and new predictability as compared to the H.B Robinson Benchmark. At Los Alamos National Laboratory, a special purpose cluster named “tebow,” was constructed such to maximize available RAM per CPU, as well as leveraging swap space with solid state hard drives, to allow larger scale depletion calculations (allowing for significantly more burnable regions than previously examined). As the MCNP6 burnup capability was scaled to larger numbers of burnable regions, a noticeable slowdown was realized.This paper details two specific computational performance strategies for improving calculation speedup: (1) retrieving cross sections during transport; and (2) tallying mechanisms specific to burnup in MCNP. To combat this slowdown new performance upgrades were developed and integrated into MCNP6 1.2.

  5. Accelerated equilibrium core composition search using a new MCNP-based simulator

    NASA Astrophysics Data System (ADS)

    Seifried, Jeffrey E.; Gorman, Phillip M.; Vujic, Jasmina L.; Greenspan, Ehud

    2014-06-01

    MocDown is a new Monte Carlo depletion and recycling simulator which couples neutron transport with MCNP and transmutation with ORIGEN. This modular approach to depletion allows for flexible operation by incorporating the accelerated progression of a complex fuel processing scheme towards equilibrium and by allowing for the online coupling of thermo-fluids feedback. MocDown also accounts for the variation of decay heat with fuel isotopics evolution. In typical cases, MocDown requires just over a day to find the equilibrium core composition for a multi-recycling fuel cycle, with a self-consistent thermo-fluids solution-a task that required between one and two weeks using previous Monte Carlo-based approaches.

  6. An investigation of voxel geometries for MCNP-based radiation dose calculations.

    PubMed

    Zhang, Juying; Bednarz, Bryan; Xu, X George

    2006-11-01

    Voxelized geometry such as those obtained from medical images is increasingly used in Monte Carlo calculations of absorbed doses. One useful application of calculated absorbed dose is the determination of fluence-to-dose conversion factors for different organs. However, confusion still exists about how such a geometry is defined and how the energy deposition is best computed, especially involving a popular code, MCNP5. This study investigated two different types of geometries in the MCNP5 code, cell and lattice definitions. A 10 cm x 10 cm x 10 cm test phantom, which contained an embedded 2 cm x 2 cm x 2 cm target at its center, was considered. A planar source emitting parallel photons was also considered in the study. The results revealed that MCNP5 does not calculate total target volume for multi-voxel geometries. Therefore, tallies which involve total target volume must be divided by the user by the total number of voxels to obtain a correct dose result. Also, using planar source areas greater than the phantom size results in the same fluence-to-dose conversion factor. PMID:17023800

  7. A Modification of the Isotope Generation and Depletion Code System ORIGEN. CCC-702/ORIGEN-ARP is recommended for new ORIGEN users.

    Energy Science and Technology Software Center (ESTSC)

    1984-05-04

    Version 00 KORIGEN is a modification of the isotope generation and depletion code system CCC-217/ORIGEN. ORIGEN solved the equations of radioactive growth and decay allowing continuous first order chemical processing and a neutron flux described by a three-region spectrum. Complex decay and transmutation schemes were treated. Note that this package has not been updated in many years; and all new ORIGEN users are advised to request the CCC-702/ORIGEN-ARP package, which is a PC application formore » Windows 95/NT or later.« less

  8. The RNA binding KH domain of Spoonbill depletes pathogenic non-coding spinocerebellar ataxia 8 transcripts and suppresses neurodegeneration in Drosophila.

    PubMed

    Tripathi, Bipin K; Surabhi, Satya; Bhaskar, Pradeep K; Mukherjee, Ashim; Mutsuddi, Mousumi

    2016-09-01

    Spinocerebellar ataxia 8 (SCA8) pathogenesis is a resultant of gain-of-function machinery that primarily results at the RNA level. It has been reported that expanded non-coding CTG trinucleotide repeat in the ATXN8OS transcripts leads to SCA8 coupled neurodegeneration. Targeted depletion of pathogenic SCA8 transcripts is a viable therapeutic approach. In this report we have focused on the suppression of toxic RNA gain-of-function associated with SCA8. We report suppression of SCA8 associated neurodegeneration by KH RNA binding domain of Spoonbill. KH domain suppresses pathogenic SCA8 associated phenotype in adult flies. Ectopic expression of KH domain leads to massive reduction in the number and size of SCA8 RNA foci. We show that Spoonbill interacts with toxic SCA8 transcripts via its KH domain and promotes its depletion. Till date, no attempts have been made for therapeutic intervention of SCA8 pathogenesis. Further characterization of Spoonbill KH domain may aid us in designing peptide based therapeutics for SCA8 associated neurodegeneration. PMID:27302466

  9. An MCNP-based model for the evaluation of the photoneutron dose in high energy medical electron accelerators.

    PubMed

    Carinou, Eleutheria; Stamatelatos, Ion Evangelos; Kamenopoulou, Vassiliki; Georgolopoulou, Paraskevi; Sandilos, Panayotis

    The development of a computational model for the treatment head of a medical electron accelerator (Elekta/Philips SL-18) by the Monte Carlo code mcnp-4C2 is discussed. The model includes the major components of the accelerator head and a pmma phantom representing the patient body. Calculations were performed for a 14 MeV electron beam impinging on the accelerator target and a 10 cmx10 cm beam area at the isocentre. The model was used in order to predict the neutron ambient dose equivalent at the isocentre level and moreover the neutron absorbed dose distribution within the phantom. Calculations were validated against experimental measurements performed by gold foil activation detectors. The results of this study indicated that the equivalent dose at tissues or organs adjacent to the treatment field due to photoneutrons could be up to 10% of the total peripheral dose, for the specific accelerator characteristics examined. Therefore, photoneutrons should be taken into account when accurate dose calculations are required to sensitive tissues that are adjacent to the therapeutic X-ray beam. The method described can be extended to other accelerators and collimation configurations as well, upon specification of treatment head component dimensions, composition and nominal accelerating potential. PMID:18348851

  10. Isotope Generation and Depletion Code with Libraries Based on JENDL3.2. New ORIGEN users are advised to get CCC-750/SCALE6 and run the ORIGEN-ARP code system in that package.

    Energy Science and Technology Software Center (ESTSC)

    2001-11-30

    Version 00 ORIGEN-JENDL32 includes a modified version of the CCC-371/ORIGEN2.1 code along with the libraries from that package plus new libraries, which are based on current reactor designs using the newest nuclear data file developed in Japan, JENDL-3.2. The new libraries contain not only one-group cross section data but also variable actinide cross sections and decay and fission yield data. Main objectives of the libraries are to calculate isotopic compositions averaged over whole fuel assembliesmore » for the case of LWR and isotopic compositions averaged over a whole core for the case of FBR. Target fuel assemblies are PWR 17?17 type and BWR 8?8 or 9?9 type. Target core and blanket types of FBR are chosen from several considered specifications. Evaluation of the LWR libraries was conducted by the analysis of latest post irradiation examinations carried out in Japan Atomic Energy Research Institute. The evaluation showed improved results of many isotopes. Evaluation of the FBR libraries was carried out by the comparison between new and old libraries of FBR. The calculated weights of several isotopes presented large differences. ORIGEN is a computer code system for calculating the buildup, decay, and processing of radioactive materials. ORIGEN2.1 is a revised version of CCC-217/ORIGEN and incorporates updates of the reactor models, cross sections, fission product yields, decay data, and decay photon data, as well as the source code. ORIGEN2.1 includes libraries for standard and extended-burnup PWR and BWR calculations, which are documented in ORNL/TM-11018. Note that new ORIGEN users are generally advised to request the CCC-750/SCALE 6 package, which contains ORIGEN-S and control modules to run it, in addition to a newer selection of data libraries.« less

  11. Specification for the VERA Depletion Benchmark Suite

    SciTech Connect

    Kim, Kang Seog

    2015-12-17

    CASL-X-2015-1014-000 iii Consortium for Advanced Simulation of LWRs EXECUTIVE SUMMARY The CASL neutronics simulator MPACT is under development for the neutronics and T-H coupled simulation for the pressurized water reactor. MPACT includes the ORIGEN-API and internal depletion module to perform depletion calculations based upon neutron-material reaction and radioactive decay. It is a challenge to validate the depletion capability because of the insufficient measured data. One of the detoured methods to validate it is to perform a code-to-code comparison for benchmark problems. In this study a depletion benchmark suite has been developed and a detailed guideline has been provided to obtain meaningful computational outcomes which can be used in the validation of the MPACT depletion capability.

  12. DEPLETED URANIUM TECHNICAL WORK

    EPA Science Inventory

    The Depleted Uranium Technical Work is designed to convey available information and knowledge about depleted uranium to EPA Remedial Project Managers, On-Scene Coordinators, contractors, and other Agency managers involved with the remediation of sites contaminated with this mater...

  13. CO depletion in the Gould Belt clouds

    NASA Astrophysics Data System (ADS)

    Christie, H.; Viti, S.; Yates, J.; Hatchell, J.; Fuller, G. A.; Duarte-Cabral, A.; Sadavoy, S.; Buckle, J. V.; Graves, S.; Roberts, J.; Nutter, D.; Davis, C.; White, G. J.; Hogerheijde, M.; Ward-Thompson, D.; Butner, H.; Richer, J.; Di Francesco, J.

    2012-05-01

    We present a statistical comparison of CO depletion in a set of local molecular clouds within the Gould Belt using Sub-millimetre Common User Bolometer Array (SCUBA) and Heterodyne Array Receiver Programme (HARP) data. This is the most wide-ranging study of depletion thus far within the Gould Belt. We estimate CO column densities assuming local thermodynamic equilibrium and, for a selection of sources, using the radiative transfer code RADEX in order to compare the two column density estimation methods. High levels of depletion are seen in the centres of several dust cores in all the clouds. We find that in the gas surrounding protostars, levels of depletion are somewhat lower than for starless cores with the exception of a few highly depleted protostellar cores in Serpens and NGC 2024. There is a tentative correlation between core mass and core depletion, particularly in Taurus and Serpens. Taurus has, on average, the highest levels of depletion. Ophiuchus has low average levels of depletion which could perhaps be related to the anomalous dust grain size distribution observed in this cloud. High levels of depletion are often seen around the edges of regions of optical emission (Orion) or in more evolved or less dynamic regions such as the bowl of L1495 in Taurus and the north-western region of Serpens.

  14. Water Depletion Threatens Agriculture

    NASA Astrophysics Data System (ADS)

    Brauman, K. A.; Richter, B. D.; Postel, S.; Floerke, M.; Malsy, M.

    2014-12-01

    Irrigated agriculture is the human activity that has by far the largest impact on water, constituting 85% of global water consumption and 67% of global water withdrawals. Much of this water use occurs in places where water depletion, the ratio of water consumption to water availability, exceeds 75% for at least one month of the year. Although only 17% of global watershed area experiences depletion at this level or more, nearly 30% of total cropland and 60% of irrigated cropland are found in these depleted watersheds. Staple crops are particularly at risk, with 75% of global irrigated wheat production and 65% of irrigated maize production found in watersheds that are at least seasonally depleted. Of importance to textile production, 75% of cotton production occurs in the same watersheds. For crop production in depleted watersheds, we find that one half to two-thirds of production occurs in watersheds that have not just seasonal but annual water shortages, suggesting that re-distributing water supply over the course of the year cannot be an effective solution to shortage. We explore the degree to which irrigated production in depleted watersheds reflects limitations in supply, a byproduct of the need for irrigation in perennially or seasonally dry landscapes, and identify heavy irrigation consumption that leads to watershed depletion in more humid climates. For watersheds that are not depleted, we evaluate the potential impact of an increase in irrigated production. Finally, we evaluate the benefits of irrigated agriculture in depleted and non-depleted watersheds, quantifying the fraction of irrigated production going to food production, animal feed, and biofuels.

  15. Halo Star Lithium Depletion

    SciTech Connect

    Pinsonneault, M. H.; Walker, T. P.; Steigman, G.; Narayanan, Vijay K.

    1999-12-10

    The depletion of lithium during the pre-main-sequence and main-sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. Previous work has indicated a wide range of possible depletion factors, ranging from minimal in standard (nonrotating) stellar models to as much as an order of magnitude in models that include rotational mixing. Recent progress in the study of the angular momentum evolution of low-mass stars permits the construction of theoretical models capable of reproducing the angular momentum evolution of low-mass open cluster stars. The distribution of initial angular momenta can be inferred from stellar rotation data in young open clusters. In this paper we report on the application of these models to the study of lithium depletion in main-sequence halo stars. A range of initial angular momenta produces a range of lithium depletion factors on the main sequence. Using the distribution of initial conditions inferred from young open clusters leads to a well-defined halo lithium plateau with modest scatter and a small population of outliers. The mass-dependent angular momentum loss law inferred from open cluster studies produces a nearly flat plateau, unlike previous models that exhibited a downward curvature for hotter temperatures in the 7Li-Teff plane. The overall depletion factor for the plateau stars is sensitive primarily to the solar initial angular momentum used in the calibration for the mixing diffusion coefficients. Uncertainties remain in the treatment of the internal angular momentum transport in the models, and the potential impact of these uncertainties on our results is discussed. The 6Li/7Li depletion ratio is also examined. We find that the dispersion in the plateau and the 6Li/7Li depletion ratio scale with the absolute 7Li depletion in the plateau, and we use observational data to set bounds on the 7Li depletion in main-sequence halo

  16. Cholesterol depletion induces autophagy

    SciTech Connect

    Cheng, Jinglei; Ohsaki, Yuki; Tauchi-Sato, Kumi; Fujita, Akikazu; Fujimoto, Toyoshi . E-mail: tfujimot@med.nagoya-u.ac.jp

    2006-12-08

    Autophagy is a mechanism to digest cells' own components, and its importance in many physiological and pathological processes is being recognized. But the molecular mechanism that regulates autophagy is not understood in detail. In the present study, we found that cholesterol depletion induces macroautophagy. The cellular cholesterol in human fibroblasts was depleted either acutely using 5 mM methyl-{beta}-cyclodextrin or 10-20 {mu}g/ml nystatin for 1 h, or metabolically by 20 {mu}M mevastatin and 200 {mu}M mevalonolactone along with 10% lipoprotein-deficient serum for 2-3 days. By any of these protocols, marked increase of LC3-II was detected by immunoblotting and by immunofluorescence microscopy, and the increase was more extensive than that caused by amino acid starvation, i.e., incubation in Hanks' solution for several hours. The induction of autophagic vacuoles by cholesterol depletion was also observed in other cell types, and the LC3-positive membranes were often seen as long tubules, >50 {mu}m in length. The increase of LC3-II by methyl-{beta}-cyclodextrin was suppressed by phosphatidylinositol 3-kinase inhibitors and was accompanied by dephosphorylation of mammalian target of rapamycin. By electron microscopy, autophagic vacuoles induced by cholesterol depletion were indistinguishable from those seen after amino acid starvation. These results demonstrate that a decrease in cholesterol activates autophagy by a phosphatidylinositol 3-kinase-dependent mechanism.

  17. Depleted uranium disposal options.

    SciTech Connect

    Biwer, B. M.; Ranek, N. L.; Goldberg, M.; Avci, H. I.

    2000-04-01

    Depleted uranium hexafluoride (UF{sub 6}) has been produced in the United States since the 1940s as part of both the military program and the civilian nuclear energy program. The U.S. Department of Energy (DOE) is the agency responsible for managing most of the depleted UF{sub 6} that has been produced in the United States. The total quantity of depleted UF{sub 6} that DOE has to or will have to manage is approximately 700,000 Mg. Studies have been conducted to evaluate the various alternatives for managing this material. This paper evaluates and summarizes the alternative of disposal as low-level waste (LLW). Results of the analysis indicate that UF{sub 6} needs to be converted to a more stable form, such as U{sub 3}O{sub 8}, before disposal as LLW. Estimates of the environmental impacts of disposal in a dry environment are within the currently applicable standards and regulations. Of the currently operating LLW disposal facilities, available information indicates that either of two DOE facilities--the Hanford Site or the Nevada Test Site--or a commercial facility--Envirocare of Utah--would be able to dispose of up to the entire DOE inventory of depleted UF{sub 6}.

  18. Revisiting Antarctic Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Grooß, Jens-Uwe; Tritscher, Ines; Müller, Rolf

    2015-04-01

    Antarctic ozone depletion is known for almost three decades and it has been well settled that it is caused by chlorine catalysed ozone depletion inside the polar vortex. However, there are still some details, which need to be clarified. In particular, there is a current debate on the relative importance of liquid aerosol and crystalline NAT and ice particles for chlorine activation. Particles have a threefold impact on polar chlorine chemistry, temporary removal of HNO3 from the gas-phase (uptake), permanent removal of HNO3 from the atmosphere (denitrification), and chlorine activation through heterogeneous reactions. We have performed simulations with the Chemical Lagrangian Model of the Stratosphere (CLaMS) employing a recently developed algorithm for saturation-dependent NAT nucleation for the Antarctic winters 2011 and 2012. The simulation results are compared with different satellite observations. With the help of these simulations, we investigate the role of the different processes responsible for chlorine activation and ozone depletion. Especially the sensitivity with respect to the particle type has been investigated. If temperatures are artificially forced to only allow cold binary liquid aerosol, the simulation still shows significant chlorine activation and ozone depletion. The results of the 3-D Chemical Transport Model CLaMS simulations differ from purely Lagrangian longtime trajectory box model simulations which indicates the importance of mixing processes.

  19. Ozone depletion by hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, Margaret M.; Fleming, Eric L.; Newman, Paul A.; Li, Feng; Mlawer, Eli; Cady-Pereira, Karen; Bailey, Roshelle

    2015-10-01

    Atmospheric concentrations of hydrofluorocarbons (HFCs) are projected to increase considerably in the coming decades. Chemistry climate model simulations forced by current projections show that HFCs will impact the global atmosphere increasingly through 2050. As strong radiative forcers, HFCs increase tropospheric and stratospheric temperatures, thereby enhancing ozone-destroying catalytic cycles and modifying the atmospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Simulations with the NASA Goddard Space Flight Center 2-D model show that HFC-125 is the most important contributor to HFC-related atmospheric change in 2050; its effects are comparable to the combined impacts of HFC-23, HFC-32, HFC-134a, and HFC-143a. Incorporating the interactions between chemistry, radiation, and dynamics, ozone depletion potentials (ODPs) for HFCs range from 0.39 × 10-3 to 30.0 × 10-3, approximately 100 times larger than previous ODP estimates which were based solely on chemical effects.

  20. Depleted uranium management alternatives

    SciTech Connect

    Hertzler, T.J.; Nishimoto, D.D.

    1994-08-01

    This report evaluates two management alternatives for Department of Energy depleted uranium: continued storage as uranium hexafluoride, and conversion to uranium metal and fabrication to shielding for spent nuclear fuel containers. The results will be used to compare the costs with other alternatives, such as disposal. Cost estimates for the continued storage alternative are based on a life-cycle of 27 years through the year 2020. Cost estimates for the recycle alternative are based on existing conversion process costs and Capital costs for fabricating the containers. Additionally, the recycle alternative accounts for costs associated with intermediate product resale and secondary waste disposal for materials generated during the conversion process.

  1. Tank depletion flow controller

    DOEpatents

    Georgeson, Melvin A.

    1976-10-26

    A flow control system includes two bubbler tubes installed at different levels within a tank containing such as radioactive liquid. As the tank is depleted, a differential pressure transmitter monitors pressure differences imparted by the two bubbler tubes at a remote, shielded location during uniform time intervals. At the end of each uniform interval, balance pots containing a dense liquid are valved together to equalize the pressures. The resulting sawtooth-shaped signal generated by the differential pressure transmitter is compared with a second sawtooth signal representing the desired flow rate during each time interval. Variations in the two signals are employed by a control instrument to regulate flow rate.

  2. Ozone Depletion by Hydrofluorocarbons

    NASA Astrophysics Data System (ADS)

    Hurwitz, M.; Fleming, E. L.; Newman, P. A.; Li, F.; Mlawer, E. J.; Cady-Pereira, K. E.; Bailey, R.

    2015-12-01

    Hydrofluorocarbons (HFCs) are second-generation replacements for the chlorofluorocarbons (CFCs), halons and other substances that caused the 'ozone hole'. Atmospheric concentrations of HFCs are projected to increase dramatically in the coming decades. Coupled chemistry-climate simulations forced by these projections show that HFCs will impact the global atmosphere in 2050. As strong radiative forcers, HFCs modulate atmospheric temperature, thereby changing ozone-destroying catalytic cycles and enhancing the stratospheric circulation. These changes lead to a weak depletion of stratospheric ozone. Sensitivity simulations with the NASA Goddard Space Flight Center (GSFC) 2D model show that HFC-125 is the most important contributor to atmospheric change in 2050, as compared with HFC-23, HFC-32, HFC-134a and HFC-143a. Incorporating the interactions between chemistry, radiation and dynamics, for a likely 2050 climate, ozone depletion potentials (ODPs) for HFCs range from 4.3x10-4 to 3.5x10-2; previously HFCs were assumed to have negligible ODPs since these species lack chlorine or bromine atoms. The ozone impacts of HFCs are further investigated with the Goddard Earth Observing System Chemistry-Climate Model (GEOSCCM). The GEOSCCM is a three-dimensional, fully coupled ocean-atmosphere model with interactive stratospheric chemistry. Sensitivity simulations in which CO2, CFC-11 and HCFC-22 are enhanced individually are used as proxies for the atmospheric response to the HFC concentrations expected by the mid-21st century. Sensitivity simulations provide quantitative estimates of the impacts of these greenhouse gases on global total ozone, and can be used to assess their effects on the recovery of Antarctic ozone.

  3. Depletion analysis of the UMLRR reactor core using MCNP6

    NASA Astrophysics Data System (ADS)

    Odera, Dim Udochukwu

    Accurate knowledge of the neutron flux and temporal nuclide inventory in reactor physics calculations is necessary for a variety of application in nuclear engineering such as criticality safety, safeguards, and spent fuel storage. The Monte Carlo N- Particle (MCNP6) code with integrated buildup depletion code (CINDER90) provides a high-fidelity tool that can be used to perform 3D, full core simulation to evaluate fissile material utilization, and nuclide inventory calculations as a function of burnup. The University of Massachusetts Lowell Research Reactor (UMLRR) reactor has been modeled with the deterministic based code, VENTURE and with an older version of MCNP (MCNP5). The MIT developed MCODE (MCNP ORIGEN DEPLETION CODE) was used previously to perform some limited depletion calculations. This work chronicles the use of MCNP6, released in June 2013, to perform coupled neutronics and depletion calculation. The results are compared to previously benchmarked results. Furthermore, the code is used to determine the ratio of fission products 134Cs and 137Cs (burnup indicators), and the resultant ratio is compared to the burnup of the UMLRR.

  4. 12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF DEPLETED URANIUM INGOT AND MOLDS. DEPLETED URANIUM CASTING OPERATIONS CEASED IN 1988. (11/14/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  5. Depletion optimization of lumped burnable poisons in pressurized water reactors

    SciTech Connect

    Kodah, Z.H.

    1982-01-01

    Techniques were developed to construct a set of basic poison depletion curves which deplete in a monotonical manner. These curves were combined to match a required optimized depletion profile by utilizing either linear or non-linear programming methods. Three computer codes, LEOPARD, XSDRN, and EXTERMINATOR-2 were used in the analyses. A depletion routine was developed and incorporated into the XSDRN code to allow the depletion of fuel, fission products, and burnable poisons. The Three Mile Island Unit-1 reactor core was used in this work as a typical PWR core. Two fundamental burnable poison rod designs were studied. They are a solid cylindrical poison rod and an annular cylindrical poison rod with water filling the central region.These two designs have either a uniform mixture of burnable poisons or lumped spheroids of burnable poisons in the poison region. Boron and gadolinium are the two burnable poisons which were investigated in this project. Thermal self-shielding factor calculations for solid and annular poison rods were conducted. Also expressions for overall thermal self-shielding factors for one or more than one size group of poison spheroids inside solid and annular poison rods were derived and studied. Poison spheroids deplete at a slower rate than the poison mixture because each spheroid exhibits some self-shielding effects of its own. The larger the spheroid, the higher the self-shielding effects due to the increase in poison concentration.

  6. Depleted Uranium in Repositories

    SciTech Connect

    Haire, M.J.; Croff, A.G.

    1997-12-31

    For uranium to be useful in most fission nuclear reactors, it must be enriched (i.e. the concentration of the fissile isotope 235U must be increased). Therefore, depleted uranium (DU)-uranium which has less than naturally occurring concentrations of 235U-is a co-product of the enrichment process. Four to six tons of DU exist for every ton of fresh light water reactor fuel. There were 407,006 MgU 407,000 metric tons (t) of DU stored on U.S. Department of Energy (DOE) sites as of July 1993. If this DU were to be declared surplus, converted to a stable oxide form, and emplaced in a near surface disposal facility, the costs are estimated to be several billion dollars. However, the U.S. Nuclear Regulatory Commission has stated that near surface disposal of large quantities of DU tails is not appropriate. Thus, there is the possibility that disposition via disposal will be in a deep geological repository. One alternative that may significantly reduce the cost of DU disposition is to use it beneficially. In fact, DOE has begun the Beneficial Uses of DU Project to identify large scale uses of DU and to encourage its reuse. Several beneficial uses, many of which involve applications in the repository per se or in managing the wastes to go into the repository, are discussed in this report.

  7. The Toxicity of Depleted Uranium

    PubMed Central

    Briner, Wayne

    2010-01-01

    Depleted uranium (DU) is an emerging environmental pollutant that is introduced into the environment primarily by military activity. While depleted uranium is less radioactive than natural uranium, it still retains all the chemical toxicity associated with the original element. In large doses the kidney is the target organ for the acute chemical toxicity of this metal, producing potentially lethal tubular necrosis. In contrast, chronic low dose exposure to depleted uranium may not produce a clear and defined set of symptoms. Chronic low-dose, or subacute, exposure to depleted uranium alters the appearance of milestones in developing organisms. Adult animals that were exposed to depleted uranium during development display persistent alterations in behavior, even after cessation of depleted uranium exposure. Adult animals exposed to depleted uranium demonstrate altered behaviors and a variety of alterations to brain chemistry. Despite its reduced level of radioactivity evidence continues to accumulate that depleted uranium, if ingested, may pose a radiologic hazard. The current state of knowledge concerning DU is discussed. PMID:20195447

  8. Stratospheric ozone depletion

    PubMed Central

    Rowland, F. Sherwood

    2006-01-01

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290–320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime—the ‘Antarctic ozone hole’. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  9. Stratospheric ozone depletion.

    PubMed

    Rowland, F Sherwood

    2006-05-29

    Solar ultraviolet radiation creates an ozone layer in the atmosphere which in turn completely absorbs the most energetic fraction of this radiation. This process both warms the air, creating the stratosphere between 15 and 50 km altitude, and protects the biological activities at the Earth's surface from this damaging radiation. In the last half-century, the chemical mechanisms operating within the ozone layer have been shown to include very efficient catalytic chain reactions involving the chemical species HO, HO2, NO, NO2, Cl and ClO. The NOX and ClOX chains involve the emission at Earth's surface of stable molecules in very low concentration (N2O, CCl2F2, CCl3F, etc.) which wander in the atmosphere for as long as a century before absorbing ultraviolet radiation and decomposing to create NO and Cl in the middle of the stratospheric ozone layer. The growing emissions of synthetic chlorofluorocarbon molecules cause a significant diminution in the ozone content of the stratosphere, with the result that more solar ultraviolet-B radiation (290-320 nm wavelength) reaches the surface. This ozone loss occurs in the temperate zone latitudes in all seasons, and especially drastically since the early 1980s in the south polar springtime-the 'Antarctic ozone hole'. The chemical reactions causing this ozone depletion are primarily based on atomic Cl and ClO, the product of its reaction with ozone. The further manufacture of chlorofluorocarbons has been banned by the 1992 revisions of the 1987 Montreal Protocol of the United Nations. Atmospheric measurements have confirmed that the Protocol has been very successful in reducing further emissions of these molecules. Recovery of the stratosphere to the ozone conditions of the 1950s will occur slowly over the rest of the twenty-first century because of the long lifetime of the precursor molecules. PMID:16627294

  10. CRDIAC: Coupled Reactor Depletion Instrument with Automated Control

    SciTech Connect

    Steven K. Logan

    2012-08-01

    When modeling the behavior of a nuclear reactor over time, it is important to understand how the isotopes in the reactor will change, or transmute, over that time. This is especially important in the reactor fuel itself. Many nuclear physics modeling codes model how particles interact in the system, but do not model this over time. Thus, another code is used in conjunction with the nuclear physics code to accomplish this. In our code, Monte Carlo N-Particle (MCNP) codes and the Multi Reactor Transmutation Analysis Utility (MRTAU) were chosen as the codes to use. In this way, MCNP would produce the reaction rates in the different isotopes present and MRTAU would use cross sections generated from these reaction rates to determine how the mass of each isotope is lost or gained. Between these two codes, the information must be altered and edited for use. For this, a Python 2.7 script was developed to aid the user in getting the information in the correct forms. This newly developed methodology was called the Coupled Reactor Depletion Instrument with Automated Controls (CRDIAC). As is the case in any newly developed methodology for modeling of physical phenomena, CRDIAC needed to be verified against similar methodology and validated against data taken from an experiment, in our case AFIP-3. AFIP-3 was a reduced enrichment plate type fuel tested in the ATR. We verified our methodology against the MCNP Coupled with ORIGEN2 (MCWO) method and validated our work against the Post Irradiation Examination (PIE) data. When compared to MCWO, the difference in concentration of U-235 throughout Cycle 144A was about 1%. When compared to the PIE data, the average bias for end of life U-235 concentration was about 2%. These results from CRDIAC therefore agree with the MCWO and PIE data, validating and verifying CRDIAC. CRDIAC provides an alternative to using ORIGEN-based methodology, which is useful because CRDIAC's depletion code, MRTAU, uses every available isotope in its depletion

  11. Ego depletion impairs implicit learning.

    PubMed

    Thompson, Kelsey R; Sanchez, Daniel J; Wesley, Abigail H; Reber, Paul J

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent. PMID:25275517

  12. Enhanced Monte-Carlo-Linked Depletion Capabilities in MCNPX

    SciTech Connect

    Fensin, Michael L.; Hendricks, John S.; Anghaie, Samim

    2006-07-01

    As advanced reactor concepts challenge the accuracy of current modeling technologies, a higher-fidelity depletion calculation is necessary to model time-dependent core reactivity properly for accurate cycle length and safety margin determinations. The recent integration of CINDER90 into the MCNPX Monte Carlo radiation transport code provides a completely self-contained Monte-Carlo-linked depletion capability. Two advances have been made in the latest MCNPX capability based on problems observed in pre-released versions: continuous energy collision density tracking and proper fission yield selection. Pre-released versions of the MCNPX depletion code calculated the reaction rates for (n,2n), (n,3n), (n,p), (n,a), and (n,?) by matching the MCNPX steady-state 63-group flux with 63-group cross sections inherent in the CINDER90 library and then collapsing to one-group collision densities for the depletion calculation. This procedure led to inaccuracies due to the miscalculation of the reaction rates resulting from the collapsed multi-group approach. The current version of MCNPX eliminates this problem by using collapsed one-group collision densities generated from continuous energy reaction rates determined during the MCNPX steady-state calculation. MCNPX also now explicitly determines the proper fission yield to be used by the CINDER90 code for the depletion calculation. The CINDER90 code offers a thermal, fast, and high-energy fission yield for each fissile isotope contained in the CINDER90 data file. MCNPX determines which fission yield to use for a specified problem by calculating the integral fission rate for the defined energy boundaries (thermal, fast, and high energy), determining which energy range contains the majority of fissions, and then selecting the appropriate fission yield for the energy range containing the majority of fissions. The MCNPX depletion capability enables complete, relatively easy-to-use depletion calculations in a single Monte Carlo code

  13. Clinical coding. Code breakers.

    PubMed

    Mathieson, Steve

    2005-02-24

    --The advent of payment by results has seen the role of the clinical coder pushed to the fore in England. --Examinations for a clinical coding qualification began in 1999. In 2004, approximately 200 people took the qualification. --Trusts are attracting people to the role by offering training from scratch or through modern apprenticeships. PMID:15768716

  14. Depleting depletion: Polymer swelling in poor solvent mixtures

    NASA Astrophysics Data System (ADS)

    Mukherji, Debashish; Marques, Carlos; Stuehn, Torsten; Kremer, Kurt

    A polymer collapses in a solvent when the solvent particles dislike monomers more than the repulsion between monomers. This leads to an effective attraction between monomers, also referred to as depletion induced attraction. This attraction is the key factor behind standard polymer collapse in poor solvents. Strikingly, even if a polymer exhibits poor solvent condition in two different solvents, it can also swell in mixtures of these two poor solvents. This collapse-swelling-collapse scenario is displayed by poly(methyl methacrylate) (PMMA) in aqueous alcohol. Using molecular dynamics simulations of a thermodynamically consistent generic model and theoretical arguments, we unveil the microscopic origin of this phenomenon. Our analysis suggests that a subtle interplay of the bulk solution properties and the local depletion forces reduces depletion effects, thus dictating polymer swelling in poor solvent mixtures.

  15. Depletable externalities and Pigouvian taxation

    SciTech Connect

    Freeman, A.M. III

    1984-06-01

    In their book Baumol and Oates (The Theory of Environmental Policy: Externalities, Public Outlays, and the Quality of Life; Prentice-Hall, Englewood Cliffs, NJ (1975).) argue that whether an externality is depletable (private) or undepletable (public) is the key characteristic in determining the optimal pricing pattern. They argue that unlike the undepletable case a negative depletable externality requires not only a charge or tax on the generator of the externality but a payment or compensation to the victim in order to achieve Pareto optimality. It is shown that the key characteristic determining whether compensation of victims is required for efficiency is not the depletability of the externality but whether the victim can costlessly control or limit the amount of the damaging substance received. 6 references.

  16. Fully depleted back illuminated CCD

    DOEpatents

    Holland, Stephen Edward

    2001-01-01

    A backside illuminated charge coupled device (CCD) is formed of a relatively thick high resistivity photon sensitive silicon substrate, with frontside electronic circuitry, and an optically transparent backside ohmic contact for applying a backside voltage which is at least sufficient to substantially fully deplete the substrate. A greater bias voltage which overdepletes the substrate may also be applied. One way of applying the bias voltage to the substrate is by physically connecting the voltage source to the ohmic contact. An alternate way of applying the bias voltage to the substrate is to physically connect the voltage source to the frontside of the substrate, at a point outside the depletion region. Thus both frontside and backside contacts can be used for backside biasing to fully deplete the substrate. Also, high resistivity gaps around the CCD channels and electrically floating channel stop regions can be provided in the CCD array around the CCD channels. The CCD array forms an imaging sensor useful in astronomy.

  17. DOPAMINE DEPLETION SLOWS RETINAL TRANSMISSION

    EPA Science Inventory

    In male hooded rats, depletion of norepinephrine and dopamine by a-methyl-paratyrosine (AMT) significantly increased the latencies of early peaks in flash-evoked potentials recorded from the visual cortex, lateral geniculate nucleus, and optic tract. These effects were not produc...

  18. SCISAT to study ozone depletion

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    The Canadian Space Agency's SCISAT satellite began its mission to study the depletion of the ozone layer, following a successful launch on 12 August.The goal for the atmospheric chemistry experiment, which is SCISAT's mission, is to improve the scientific understanding of the complex chemical changes occurring in the upper atmosphere, particularly in the far north, according to Canada's Minister of Industry, Allan Rock.

  19. Ozone depletion, paradigms, and politics

    SciTech Connect

    Iman, R.L.

    1993-10-01

    The destruction of the Earth`s protective ozone layer is a prime environmental concern. Industry has responded to this environmental problem by: implementing conservation techniques to reduce the emission of ozone-depleting chemicals (ODCs); using alternative cleaning solvents that have lower ozone depletion potentials (ODPs); developing new, non-ozone-depleting solvents, such as terpenes; and developing low-residue soldering processes. This paper presents an overview of a joint testing program at Sandia and Motorola to evaluate a low-residue (no-clean) soldering process for printed wiring boards (PWBs). Such processes are in widespread use in commercial applications because they eliminate the cleaning operation. The goal of this testing program was to develop a data base that could be used to support changes in the mil-specs. In addition, a joint task force involving industry and the military has been formed to conduct a follow-up evaluation of low-residue processes that encompass the concerns of the tri-services. The goal of the task force is to gain final approval of the low-residue technology for use in military applications.

  20. Ozone Depletion from Nearby Supernovae

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Laird, Claude M.; Jackman, Charles H.; Cannizzo, John K.; Mattson, Barbara J.; Chen, Wan; Bhartia, P. K. (Technical Monitor)

    2002-01-01

    Estimates made in the 1970's indicated that a supernova occurring within tens of parsecs of Earth could have significant effects on the ozone layer. Since that time improved tools for detailed modeling of atmospheric chemistry have been developed to calculate ozone depletion, and advances have been made also in theoretical modeling of supernovae and of the resultant gamma ray spectra. In addition, one now has better knowledge of the occurrence rate of supernovae in the galaxy, and of the spatial distribution of progenitors to core-collapse supernovae. We report here the results of two-dimensional atmospheric model calculations that take as input the spectral energy distribution of a supernova, adopting various distances from Earth and various latitude impact angles. In separate simulations we calculate the ozone depletion due to both gamma rays and cosmic rays. We find that for the combined ozone depletion from these effects roughly to double the 'biologically active' UV flux received at the surface of the Earth, the supernova must occur at approximately or less than 8 parsecs.

  1. Speech coding

    NASA Astrophysics Data System (ADS)

    Gersho, Allen

    1990-05-01

    Recent advances in algorithms and techniques for speech coding now permit high quality voice reproduction at remarkably low bit rates. The advent of powerful single-ship signal processors has made it cost effective to implement these new and sophisticated speech coding algorithms for many important applications in voice communication and storage. Some of the main ideas underlying the algorithms of major interest today are reviewed. The concept of removing redundancy by linear prediction is reviewed, first in the context of predictive quantization or DPCM. Then linear predictive coding, adaptive predictive coding, and vector quantization are discussed. The concepts of excitation coding via analysis-by-synthesis, vector sum excitation codebooks, and adaptive postfiltering are explained. The main idea of vector excitation coding (VXC) or code excited linear prediction (CELP) are presented. Finally low-delay VXC coding and phonetic segmentation for VXC are described.

  2. Issues in Stratospheric Ozone Depletion.

    NASA Astrophysics Data System (ADS)

    Lloyd, Steven Andrew

    Following the announcement of the discovery of the Antarctic ozone hole in 1985 there have arisen a multitude of questions pertaining to the nature and consequences of polar ozone depletion. This thesis addresses several of these specific questions, using both computer models of chemical kinetics and the Earth's radiation field as well as laboratory kinetic experiments. A coupled chemical kinetic-radiative numerical model was developed to assist in the analysis of in situ field measurements of several radical and neutral species in the polar and mid-latitude lower stratosphere. Modeling was used in the analysis of enhanced polar ClO, mid-latitude diurnal variation of ClO, and simultaneous measurements of OH, HO_2, H_2 O and O_3. Most importantly, such modeling was instrumental in establishing the link between the observed ClO and BrO concentrations in the Antarctic polar vortex and the observed rate of ozone depletion. The principal medical concern of stratospheric ozone depletion is that ozone loss will lead to the enhancement of ground-level UV-B radiation. Global ozone climatology (40^circS to 50^ circN latitude) was incorporated into a radiation field model to calculate the biologically accumulated dosage (BAD) of UV-B radiation, integrated over days, months, and years. The slope of the annual BAD as a function of latitude was found to correspond to epidemiological data for non-melanoma skin cancers for 30^circ -50^circN. Various ozone loss scenarios were investigated. It was found that a small ozone loss in the tropics can provide as much additional biologically effective UV-B as a much larger ozone loss at higher latitudes. Also, for ozone depletions of > 5%, the BAD of UV-B increases exponentially with decreasing ozone levels. An important key player in determining whether polar ozone depletion can propagate into the populated mid-latitudes is chlorine nitrate, ClONO_2 . As yet this molecule is only indirectly accounted for in computer models and field

  3. Uplink Coding

    NASA Technical Reports Server (NTRS)

    Pollara, Fabrizio; Hamkins, Jon; Dolinar, Sam; Andrews, Ken; Divsalar, Dariush

    2006-01-01

    This viewgraph presentation reviews uplink coding. The purpose and goals of the briefing are (1) Show a plan for using uplink coding and describe benefits (2) Define possible solutions and their applicability to different types of uplink, including emergency uplink (3) Concur with our conclusions so we can embark on a plan to use proposed uplink system (4) Identify the need for the development of appropriate technology and infusion in the DSN (5) Gain advocacy to implement uplink coding in flight projects Action Item EMB04-1-14 -- Show a plan for using uplink coding, including showing where it is useful or not (include discussion of emergency uplink coding).

  4. Measured and calculated fast neutron spectra in a depleted uranium and lithium hydride shielded reactor

    NASA Technical Reports Server (NTRS)

    Lahti, G. P.; Mueller, R. A.

    1973-01-01

    Measurements of MeV neutron were made at the surface of a lithium hydride and depleted uranium shielded reactor. Four shield configurations were considered: these were assembled progressively with cylindrical shells of 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, 13-centimeter-thick lithium hydride, 5-centimeter-thick depleted uranium, and 3-centimeter-thick depleted uranium. Measurements were made with a NE-218 scintillation spectrometer; proton pulse height distributions were differentiated to obtain neutron spectra. Calculations were made using the two-dimensional discrete ordinates code DOT and ENDF/B (version 3) cross sections. Good agreement between measured and calculated spectral shape was observed. Absolute measured and calculated fluxes were within 50 percent of one another; observed discrepancies in absolute flux may be due to cross section errors.

  5. The Case of Ozone Depletion

    NASA Technical Reports Server (NTRS)

    Lambright, W. Henry

    2005-01-01

    While the National Aeronautics and Space Administration (NASA) is widely perceived as a space agency, since its inception NASA has had a mission dedicated to the home planet. Initially, this mission involved using space to better observe and predict weather and to enable worldwide communication. Meteorological and communication satellites showed the value of space for earthly endeavors in the 1960s. In 1972, NASA launched Landsat, and the era of earth-resource monitoring began. At the same time, in the late 1960s and early 1970s, the environmental movement swept throughout the United States and most industrialized countries. The first Earth Day event took place in 1970, and the government generally began to pay much more attention to issues of environmental quality. Mitigating pollution became an overriding objective for many agencies. NASA's existing mission to observe planet Earth was augmented in these years and directed more toward environmental quality. In the 1980s, NASA sought to plan and establish a new environmental effort that eventuated in the 1990s with the Earth Observing System (EOS). The Agency was able to make its initial mark via atmospheric monitoring, specifically ozone depletion. An important policy stimulus in many respects, ozone depletion spawned the Montreal Protocol of 1987 (the most significant international environmental treaty then in existence). It also was an issue critical to NASA's history that served as a bridge linking NASA's weather and land-resource satellites to NASA s concern for the global changes affecting the home planet. Significantly, as a global environmental problem, ozone depletion underscored the importance of NASA's ability to observe Earth from space. Moreover, the NASA management team's ability to apply large-scale research efforts and mobilize the talents of other agencies and the private sector illuminated its role as a lead agency capable of crossing organizational boundaries as well as the science-policy divide.

  6. Verification of a Depletion Method in SCALE for the Advanced High Temperature Reactor

    SciTech Connect

    KELLY, RYAN; Ilas, Dan

    2012-01-01

    This study describes a new method utilizing the Dancoff factor to model a non-standard TRISO fuel form characteristic of the AHTR reactor design concept for depletion analysis using the TRITON sequence of SCALE and the validation of this method by code-to-code comparisons. The fuel used in AHTR has the TRISO particles concentrated along the edges of a slab fuel element. This particular geometry prevented the use of a standard DOUBLEHET treatment, previously developed in SCALE to handle NGNP-designed fuel. The new method permits fuel depletion on complicated geometries that traditionally can be handled only by continuous energy based depletion code systems. The method was initially tested on a fuel design typical of the NGNP, where the DOUBLEHET treatment is available. A more comprehensive study was performed using the VESTA code that uses the continuous energy MCNP5 code as a transport solver and ORIGEN2.2 code for depletion calculations. Comparisons of the results indicate good agreement of whole core characteristics, such as the multiplication factor, and the isotopics, including their spatial distribution. Key isotopes analyzed included 235U, 239Pu, 240Pu and 241Pu. The results from this study indicate that the Dancoff factor method can generate estimates of core characteristics with reasonable precision for scoping studies of configurations where the DOUBLEHET treatment is unavailable.

  7. Verification of a Depletion Method in SCALE for the Advanced High Temperature Reactor

    SciTech Connect

    KELLY, RYAN; Ilas, Dan

    2013-01-01

    This study describes a new approach employing the Dancoff correction method to model the TRISO-based fuel form used by the Advanced High-Temperature Reactor (AHTR) reactor design concept. The Dancoff correction method is used to perform isotope depletion analysis using the TRITON sequence of SCALE and is verified by code-to-code comparisons. The current AHTR fuel design has TRISO particles concentrated along the edges of a slab fuel element. This geometry prevented the use of the DOUBLEHET treatment, previously developed in SCALE to model spherical and cylindrical fuel. The new method permits fuel depletion on complicated geometries that traditionally can be handled only by continuous energy based depletion code systems. The method was initially tested on a fuel configuration typical of the Next Generation Nuclear Plant (NGNP), where DOUBLEHET treatment is possible. A confirmatory study was performed on the AHTR reference core geometry using the VESTA code, which uses the continuous energy MCNP5 code as a transport solver and ORIGEN2.2 code for depletion calculations. Comparisons of the results indicate good agreement of whole core characteristics, such as the multiplication factor and the isotopics, including their spatial distribution. Key isotopes analyzed included 235U, 239Pu, 240Pu, and 241Pu. The results from this study indicate that the Dancoff factor method can generate estimates of core characteristics with reasonable precision for scoping studies of configurations where DOUBLEHET treatment cannot be performed.

  8. "When the going gets tough, who keeps going?" Depletion sensitivity moderates the ego-depletion effect.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; De Vet, Emely; Fennis, Bob M; De Ridder, Denise T D

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

  9. Biomedical consequences of ozone depletion

    NASA Astrophysics Data System (ADS)

    Coohill, Thomas P.

    1994-07-01

    It is widely agreed that a portion of the earth's protective stratospheric ozone layer is being depleted. The major effect of this ozone loss will be an increase in the amount of ultraviolet radiation (UV reaching the biosphere. This increase will be completely contained within the UVB (290nm - 320nm). It is imperative that assessments be made of the effects of this additional UVB on living organisms. This requires a detailed knowledge of the UVB photobiology of these life forms. One analytical technique to aid in the approximations is the construction of UV action spectra for such important biological end-points as human skin cancer, cataracts, immune suppression; plant photosynthesis and crop yields; and aquatic organism responses to UVB, especially the phytoplankton. Combining these action spectra with the known solar spectrum (and estimates for various ozone depletion scenarios) can give rise to a series of effectiveness spectra for these parameters. This manuscript gives a first approximation, rough estimate, for the effectiveness spectra for some of these bioresponses, and a series of crude temporary values for how a 10% ozone loss would affect the above end-points. These are not intended to masquerade as final answers, but rather, to serve as beginning attempts for a process which should be continually refined. It is hoped that these estimates will be of some limited use to agencies, such as government and industry, that have to plan now for changes in human activities that might alter future atmospheric chemistry in a beneficial manner.

  10. The 1988 Antarctic ozone depletion - Comparison with previous year depletions

    NASA Technical Reports Server (NTRS)

    Schoeberl, Mark R.; Stolarski, Richard S.; Krueger, Arlin J.

    1989-01-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15 percent during September 1988, compared to nearly 50 percent during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30-60 deg S. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  11. The 1988 Antarctic ozone depletion: Comparison with previous year depletions

    SciTech Connect

    Schoeberl, M.R.; Stolarski, R.S.; Krueger, A.J. )

    1989-05-01

    The 1988 spring Antarctic ozone depletion was observed by TOMS to be substantially smaller than in recent years. The minimum polar total ozone values declined only 15% during September 1988 compared to nearly 50% during September 1987. At southern midlatitudes, exceptionally high total ozone values were recorded beginning in July 1988. The total integrated southern hemispheric ozone increased rapidly during the Austral spring, approaching 1980 levels during October. The high midlatitude total ozone values were associated with a substantial increase in eddy activity as indicated by the standard deviation in total ozone in the zonal band 30{degree}-60{degree}S. The standard deviation also correlates with the QBO cycling of the tropical winds. Mechanisms through which the increased midlatitude eddy activity could disrupt the formation of the Antarctic ozone hole are briefly discussed.

  12. Depleted Argon from Underground Sources

    SciTech Connect

    Back, H. O.; Galbiati, C.; Goretti, A.; Loer, B.; Montanari, D.; Mosteiro, P.; Alexander, T.; Alton, A.; Rogers, H.; Kendziora, C.; Pordes, S.

    2011-04-27

    Argon is a strong scintillator and an ideal target for Dark Matter detection; however {sup 39}Ar contamination in atmospheric argon from cosmic ray interactions limits the size of liquid argon dark matter detectors due to pile-up. Argon from deep underground is depleted in {sup 39}Ar due to the cosmic ray shielding of the earth. In Cortez, Colorado, a CO{sub 2} well has been discovered to contain approximately 600 ppm of argon as a contamination in the CO{sub 2}. We first concentrate the argon locally to 3% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation, and then the N{sub 2} and He will be removed by continuous distillation to purify the argon. We have collected 26 kg of argon from the CO{sub 2} facility and a cryogenic distillation column is under construction at Fermilab to further purify the argon.

  13. Computer Code

    NASA Technical Reports Server (NTRS)

    1985-01-01

    COSMIC MINIVER, a computer code developed by NASA for analyzing aerodynamic heating and heat transfer on the Space Shuttle, has been used by Marquardt Company to analyze heat transfer on Navy/Air Force missile bodies. The code analyzes heat transfer by four different methods which can be compared for accuracy. MINIVER saved Marquardt three months in computer time and $15,000.

  14. DNA codes

    SciTech Connect

    Torney, D. C.

    2001-01-01

    We have begun to characterize a variety of codes, motivated by potential implementation as (quaternary) DNA n-sequences, with letters denoted A, C The first codes we studied are the most reminiscent of conventional group codes. For these codes, Hamming similarity was generalized so that the score for matched letters takes more than one value, depending upon which letters are matched [2]. These codes consist of n-sequences satisfying an upper bound on the similarities, summed over the letter positions, of distinct codewords. We chose similarity 2 for matches of letters A and T and 3 for matches of the letters C and G, providing a rough approximation to double-strand bond energies in DNA. An inherent novelty of DNA codes is 'reverse complementation'. The latter may be defined, as follows, not only for alphabets of size four, but, more generally, for any even-size alphabet. All that is required is a matching of the letters of the alphabet: a partition into pairs. Then, the reverse complement of a codeword is obtained by reversing the order of its letters and replacing each letter by its match. For DNA, the matching is AT/CG because these are the Watson-Crick bonding pairs. Reversal arises because two DNA sequences form a double strand with opposite relative orientations. Thus, as will be described in detail, because in vitro decoding involves the formation of double-stranded DNA from two codewords, it is reasonable to assume - for universal applicability - that the reverse complement of any codeword is also a codeword. In particular, self-reverse complementary codewords are expressly forbidden in reverse-complement codes. Thus, an appropriate distance between all pairs of codewords must, when large, effectively prohibit binding between the respective codewords: to form a double strand. Only reverse-complement pairs of codewords should be able to bind. For most applications, a DNA code is to be bi-partitioned, such that the reverse-complementary pairs are separated

  15. 26 CFR 1.1016-4 - Exhaustion, wear and tear, obsolescence, amortization, and depletion; periods during which income...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., chapter 1 of the Code, or prior income tax law, to the extent that section 1016(a)(2) does not apply, and... tax under part II of subchapter L, chapter 1 of the Code, or prior income tax law, to the extent that..., amortization, and depletion; periods during which income was not subject to tax. 1.1016-4 Section...

  16. Beneficial Uses of Depleted Uranium

    SciTech Connect

    Brown, C.; Croff, A.G.; Haire, M. J.

    1997-08-01

    Naturally occurring uranium contains 0.71 wt% {sup 235}U. In order for the uranium to be useful in most fission reactors, it must be enriched the concentration of the fissile isotope {sup 235}U must be increased. Depleted uranium (DU) is a co-product of the processing of natural uranium to produce enriched uranium, and DU has a {sup 235}U concentration of less than 0.71 wt%. In the United States, essentially all of the DU inventory is in the chemical form of uranium hexafluoride (UF{sub 6}) and is stored in large cylinders above ground. If this co-product material were to be declared surplus, converted to a stable oxide form, and disposed, the costs are estimated to be several billion dollars. Only small amounts of DU have at this time been beneficially reused. The U.S. Department of Energy (DOE) has begun the Beneficial Uses of DU Project to identify large-scale uses of DU and encourage its reuse for the primary purpose of potentially reducing the cost and expediting the disposition of the DU inventory. This paper discusses the inventory of DU and its rate of increase; DU disposition options; beneficial use options; a preliminary cost analysis; and major technical, institutional, and regulatory issues to be resolved.

  17. Depleted argon from underground sources

    SciTech Connect

    Back, H.O.; Alton, A.; Calaprice, F.; Galbiati, C.; Goretti, A.; Kendziora, C.; Loer, B.; Montanari, D.; Mosteiro, P.; Pordes, S.; /Fermilab

    2011-09-01

    Argon is a powerful scintillator and an excellent medium for detection of ionization. Its high discrimination power against minimum ionization tracks, in favor of selection of nuclear recoils, makes it an attractive medium for direct detection of WIMP dark matter. However, cosmogenic {sup 39}Ar contamination in atmospheric argon limits the size of liquid argon dark matter detectors due to pile-up. The cosmic ray shielding by the earth means that Argon from deep underground is depleted in {sup 39}Ar. In Cortez Colorado a CO{sub 2} well has been discovered to contain approximately 500ppm of argon as a contamination in the CO{sub 2}. In order to produce argon for dark matter detectors we first concentrate the argon locally to 3-5% in an Ar, N{sub 2}, and He mixture, from the CO{sub 2} through chromatographic gas separation. The N{sub 2} and He will be removed by continuous cryogenic distillation in the Cryogenic Distillation Column recently built at Fermilab. In this talk we will discuss the entire extraction and purification process; with emphasis on the recent commissioning and initial performance of the cryogenic distillation column purification.

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

    SciTech Connect

    Lancaster, D.; Machiels, A.

    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)

  19. Development of the MCNPX depletion capability: A Monte Carlo linked depletion method that automates the coupling between MCNPX and CINDER90 for high fidelity burnup calculations

    NASA Astrophysics Data System (ADS)

    Fensin, Michael Lorne

    Monte Carlo-linked depletion methods have gained recent interest due to the ability to more accurately model complex 3-dimesional geometries and better track the evolution of temporal nuclide inventory by simulating the actual physical process utilizing continuous energy coefficients. The integration of CINDER90 into the MCNPX Monte Carlo radiation transport code provides a high-fidelity completely self-contained Monte-Carlo-linked depletion capability in a well established, widely accepted Monte Carlo radiation transport code that is compatible with most nuclear criticality (KCODE) particle tracking features in MCNPX. MCNPX depletion tracks all necessary reaction rates and follows as many isotopes as cross section data permits in order to achieve a highly accurate temporal nuclide inventory solution. This work chronicles relevant nuclear history, surveys current methodologies of depletion theory, details the methodology in applied MCNPX and provides benchmark results for three independent OECD/NEA benchmarks. Relevant nuclear history, from the Oklo reactor two billion years ago to the current major United States nuclear fuel cycle development programs, is addressed in order to supply the motivation for the development of this technology. A survey of current reaction rate and temporal nuclide inventory techniques is then provided to offer justification for the depletion strategy applied within MCNPX. The MCNPX depletion strategy is then dissected and each code feature is detailed chronicling the methodology development from the original linking of MONTEBURNS and MCNP to the most recent public release of the integrated capability (MCNPX 2.6.F). Calculation results of the OECD/NEA Phase IB benchmark, H. B. Robinson benchmark and OECD/NEA Phase IVB are then provided. The acceptable results of these calculations offer sufficient confidence in the predictive capability of the MCNPX depletion method. This capability sets up a significant foundation, in a well established

  20. Depletion calculations for the McClellan Nuclear Radiation Center.

    SciTech Connect

    Klann, R. T.; Newell, D. L.

    1997-12-08

    Depletion calculations have been performed for the McClellan reactor history from January 1990 through August 1996. A database has been generated for continuing use by operations personnel which contains the isotopic inventory for all fuel elements and fuel-followed control rods maintained at McClellan. The calculations are based on the three-dimensional diffusion theory code REBUS-3 which is available through the Radiation Safety Information Computational Center (RSICC). Burnup-dependent cross-sections were developed at zero power temperatures and full power temperatures using the WIMS code (also available through RSICC). WIMS is based on discretized transport theory to calculate the neutron flux as a function of energy and position in a one-dimensional cell. Based on the initial depletion calculations, a method was developed to allow operations personnel to perform depletion calculations and update the database with a minimal amount of effort. Depletion estimates and calculations can be performed by simply entering the core loading configuration, the position of the control rods at the start and end of cycle, the reactor power level, the duration of the reactor cycle, and the time since the last reactor cycle. The depletion and buildup of isotopes of interest (heavy metal isotopes, erbium isotopes, and fission product poisons) are calculated for all fuel elements and fuel-followed control rods in the MNRC inventory. The reactivity loss from burnup and buildup of fission product poisons and the peak xenon buildup after shutdown are also calculated. The reactivity loss from going from cold zero power to hot full power can also be calculated by using the temperature-dependent, burnup-dependent cross-sections. By calculating all of these reactivity effects, operations personnel are able to estimate the total excess reactivity necessary to run the reactor for the given cycle. This method has also been used to estimate the worth of individual control rods. Using this

  1. Tritium transport vessel using depleted uranium

    SciTech Connect

    Heung, L.K.

    1995-01-01

    A tritium transport vessel using depleted uranium was tested in the laboratory using deuterium and protium. The vessel contains 0.5 kg of depleted uranium and can hold up to 18 grams of tritium. The conditions for activation, tritium loading and tritium unloading were defined. The safety aspects that included air-ingress, tritium diffusion, temperature and pressure potentials were evaluated.

  2. Concentrations of Ozone-Depleting Substances

    EPA Science Inventory

    This indicator presents trends in global concentrations of ozone-depleting substances (ODSs) from 1992 to 2009. This trend is an important environmental issue, because ODSs can deplete the atmosphere's ability to shield the Earth from harmful ultraviolet rays.

  3. High homocysteine induces betaine depletion

    PubMed Central

    Imbard, Apolline; Benoist, Jean-François; Esse, Ruben; Gupta, Sapna; Lebon, Sophie; de Vriese, An S; de Baulny, Helene Ogier; Kruger, Warren; Schiff, Manuel; Blom, Henk J.

    2015-01-01

    Betaine is the substrate of the liver- and kidney-specific betaine-homocysteine (Hcy) methyltransferase (BHMT), an alternate pathway for Hcy remethylation. We hypothesized that BHMT is a major pathway for homocysteine removal in cases of hyperhomocysteinaemia (HHcy). Therefore, we measured betaine in plasma and tissues from patients and animal models of HHcy of genetic and acquired cause. Plasma was collected from patients presenting HHcy without any Hcy interfering treatment. Plasma and tissues were collected from rat models of HHcy induced by diet and from a mouse model of cystathionine β-synthase (CBS) deficiency. S-adenosyl-methionine (AdoMet), S-adenosyl-homocysteine (AdoHcy), methionine, betaine and dimethylglycine (DMG) were quantified by ESI—LC–MS/MS. mRNA expression was quantified using quantitative real-time (QRT)-PCR. For all patients with diverse causes of HHcy, plasma betaine concentrations were below the normal values of our laboratory. In the diet-induced HHcy rat model, betaine was decreased in all tissues analysed (liver, brain, heart). In the mouse CBS deficiency model, betaine was decreased in plasma, liver, heart and brain, but was conserved in kidney. Surprisingly, BHMT expression and activity was decreased in liver. However, in kidney, BHMT and SLC6A12 expression was increased in CBS-deficient mice. Chronic HHcy, irrespective of its cause, induces betaine depletion in plasma and tissues (liver, brain and heart), indicating a global decrease in the body betaine pool. In kidney, betaine concentrations were not affected, possibly due to overexpression of the betaine transporter SLC6A12 where betaine may be conserved because of its crucial role as an osmolyte. PMID:26182429

  4. Numerical study of error propagation in Monte Carlo depletion simulations

    SciTech Connect

    Wyant, T.; Petrovic, B.

    2012-07-01

    Improving computer technology and the desire to more accurately model the heterogeneity of the nuclear reactor environment have made the use of Monte Carlo depletion codes more attractive in recent years, and feasible (if not practical) even for 3-D depletion simulation. However, in this case statistical uncertainty is combined with error propagating through the calculation from previous steps. In an effort to understand this error propagation, a numerical study was undertaken to model and track individual fuel pins in four 17 x 17 PWR fuel assemblies. By changing the code's initial random number seed, the data produced by a series of 19 replica runs was used to investigate the true and apparent variance in k{sub eff}, pin powers, and number densities of several isotopes. While this study does not intend to develop a predictive model for error propagation, it is hoped that its results can help to identify some common regularities in the behavior of uncertainty in several key parameters. (authors)

  5. Speech coding

    SciTech Connect

    Ravishankar, C., Hughes Network Systems, Germantown, MD

    1998-05-08

    Speech is the predominant means of communication between human beings and since the invention of the telephone by Alexander Graham Bell in 1876, speech services have remained to be the core service in almost all telecommunication systems. Original analog methods of telephony had the disadvantage of speech signal getting corrupted by noise, cross-talk and distortion Long haul transmissions which use repeaters to compensate for the loss in signal strength on transmission links also increase the associated noise and distortion. On the other hand digital transmission is relatively immune to noise, cross-talk and distortion primarily because of the capability to faithfully regenerate digital signal at each repeater purely based on a binary decision. Hence end-to-end performance of the digital link essentially becomes independent of the length and operating frequency bands of the link Hence from a transmission point of view digital transmission has been the preferred approach due to its higher immunity to noise. The need to carry digital speech became extremely important from a service provision point of view as well. Modem requirements have introduced the need for robust, flexible and secure services that can carry a multitude of signal types (such as voice, data and video) without a fundamental change in infrastructure. Such a requirement could not have been easily met without the advent of digital transmission systems, thereby requiring speech to be coded digitally. The term Speech Coding is often referred to techniques that represent or code speech signals either directly as a waveform or as a set of parameters by analyzing the speech signal. In either case, the codes are transmitted to the distant end where speech is reconstructed or synthesized using the received set of codes. A more generic term that is applicable to these techniques that is often interchangeably used with speech coding is the term voice coding. This term is more generic in the sense that the

  6. A parallel algorithm for implicit depletant simulations

    NASA Astrophysics Data System (ADS)

    Glaser, Jens; Karas, Andrew S.; Glotzer, Sharon C.

    2015-11-01

    We present an algorithm to simulate the many-body depletion interaction between anisotropic colloids in an implicit way, integrating out the degrees of freedom of the depletants, which we treat as an ideal gas. Because the depletant particles are statistically independent and the depletion interaction is short-ranged, depletants are randomly inserted in parallel into the excluded volume surrounding a single translated and/or rotated colloid. A configurational bias scheme is used to enhance the acceptance rate. The method is validated and benchmarked both on multi-core processors and graphics processing units for the case of hard spheres, hemispheres, and discoids. With depletants, we report novel cluster phases in which hemispheres first assemble into spheres, which then form ordered hcp/fcc lattices. The method is significantly faster than any method without cluster moves and that tracks depletants explicitly, for systems of colloid packing fraction ϕc < 0.50, and additionally enables simulation of the fluid-solid transition.

  7. Possible ozone depletions following nuclear explosions

    NASA Technical Reports Server (NTRS)

    Whitten, R. C.; Borucki, W. J.; Turco, R. P.

    1975-01-01

    The degree of depletion of the ozone layer ensuing after delivery of strategic nuclear warheads (5000 and 10,000 Mton) due to production of nitrogen oxides is theoretically assessed. Strong depletions are calculated for 16-km and 26-km altitudes, peaking 1-2 months after detonation and lasting for three years, while a significant depletion at 36 km would peak after one year. Assuming the explosions occur between 30 and 70 deg N, these effects should be much more pronounced in this region than over the Northern Hemisphere as a whole. It is concluded that Hampson's concern on this matter (1974) is well-founded.-

  8. QR Codes

    ERIC Educational Resources Information Center

    Lai, Hsin-Chih; Chang, Chun-Yen; Li, Wen-Shiane; Fan, Yu-Lin; Wu, Ying-Tien

    2013-01-01

    This study presents an m-learning method that incorporates Integrated Quick Response (QR) codes. This learning method not only achieves the objectives of outdoor education, but it also increases applications of Cognitive Theory of Multimedia Learning (CTML) (Mayer, 2001) in m-learning for practical use in a diverse range of outdoor locations. When…

  9. Ray-Based Calculations with DEPLETE of Laser Backscatter in ICF Targets

    SciTech Connect

    Strozzi, D J; Williams, E; Hinkel, D; Froula, D; London, R; Callahan, D

    2008-05-19

    A steady-state model for Brillouin and Raman backscatter along a laser ray path is presented. The daughter plasma waves are treated in the strong damping limit, and have amplitudes given by the (linear) kinetic response to the ponderomotive drive. Pump depletion, inverse-bremsstrahlung damping, bremsstrahlung emission, Thomson scattering off density fluctuations, and whole-beam focusing are included. The numerical code Deplete, which implements this model, is described. The model is compared with traditional linear gain calculations, as well as 'plane-wave' simulations with the paraxial propagation code pF3D. Comparisons with Brillouin-scattering experiments at the Omega Laser Facility show that laser speckles greatly enhance the reflectivity over the Deplete results. An approximate upper bound on this enhancement is given by doubling the Deplete coupling coefficient. Analysis with Deplete of an ignition design for the National Ignition Facility (NIF), with a peak radiation temperature of 285 eV, shows encouragingly low reflectivity. Doubling the coupling to bracket speckle effects suggests a less optimistic picture. Re-absorption of Raman light is seen to be significant in this design.

  10. Depleted uranium disposition study -- Supplement, Revision 1

    SciTech Connect

    Becker, G.W.

    1993-11-01

    The Department of Energy Office of Weapons and Materials Planning has requested a supplemental study to update the recent Depleted Uranium Disposition report. This supplemental study addresses new disposition alternatives and changes in status.

  11. A definition of depletion of fish stocks

    USGS Publications Warehouse

    Van Oosten, John

    1949-01-01

    Attention was focused on the need of a common and better understanding of the term depletion as applied to the fisheries in order to eliminate if possible the existing inexactness of thought on the subject. Depletion has been confused at various times with at least ten different ideas associated with it but which, as has has heen pointed out, are not synonymous at all. In defining depletion we must recognize that the term represents a condition and must not he confounded with the cause (overfishing) that leads to this condition or with the symptoms that identify it. Depletion was defined as a reduction, through overfishing, in the level of abundance of the exploitable segment of a stock that prevents the realization of the maximum productive capacity.

  12. Silicon Depletion in the Interstellar Medium

    NASA Astrophysics Data System (ADS)

    Haris, U.; Parvathi, V. S.; Gudennavar, S. B.; Bubbly, S. G.; Murthy, J.; Sofia, U. J.

    2016-06-01

    We report interstellar silicon (Si) depletion and dust-phase column densities of Si along 131 Galactic sight lines using archival observations. The data were corrected for differences in the assumed oscillator strength. This is a much larger sample than previous studies but confirms the majority of results, which state that the depletion of Si is correlated with the average density of hydrogen along the line of sight (< n({{H}})> ) as well as the fraction of hydrogen in molecular form (f(H2)). We also find that the linear part of the extinction curve is independent of Si depletion. Si depletion is correlated with the bump strength (c3/RV) and the FUV curvature (c4/RV) suggesting that silicon plays a significant role in both the 2175 Å bump and the FUV rise.

  13. Polar stratospheric clouds and ozone depletion

    NASA Technical Reports Server (NTRS)

    Toon, Owen B.; Turco, Richard P.

    1991-01-01

    A review is presented of investigations into the correlation between the depletion of ozone and the formation of polar stratospheric clouds (PSCs). Satellite measurements from Nimbus 7 showed that over the years the depletion from austral spring to austral spring has generally worsened. Approximately 70 percent of the ozone above Antarctica, which equals about 3 percent of the earth's ozone, is lost during September and October. Various hypotheses for ozone depletion are discussed including the theory suggesting that chlorine compounds might be responsible for the ozone hole, whereby chlorine enters the atmosphere as a component of chlorofluorocarbons produced by humans. The three types of PSCs, nitric acid trihydrate, slowly cooling water-ice, and rapidly cooling water-ice clouds act as important components of the Antarctic ozone depletion. It is indicated that destruction of the ozone will be more severe each year for the next few decades, leading to a doubling in area of the Antarctic ozone hole.

  14. Exhaustible Resource Depletion: A Modified Graphical Approach.

    ERIC Educational Resources Information Center

    Tisato, Peter

    1995-01-01

    Presents a graphical analysis of the exhaustible resource depletion problem. Applies Hotelling's "r percent rule" as a new approach that operates in an "N"-period context. Includes two figures illustrating the approach. (CFR)

  15. Depleted uranium: A DOE management guide

    SciTech Connect

    1995-10-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. The annual storage and maintenance cost is approximately $10 million. This report summarizes several studies undertaken by the DOE Office of Technology Development (OTD) to evaluate options for long-term depleted uranium management. Based on studies conducted to date, the most likely use of the depleted uranium is for shielding of spent nuclear fuel (SNF) or vitrified high-level waste (HLW) containers. The alternative to finding a use for the depleted uranium is disposal as a radioactive waste. Estimated disposal costs, utilizing existing technologies, range between $3.8 and $11.3 billion, depending on factors such as applicability of the Resource Conservation and Recovery Act (RCRA) and the location of the disposal site. The cost of recycling the depleted uranium in a concrete based shielding in SNF/HLW containers, although substantial, is comparable to or less than the cost of disposal. Consequently, the case can be made that if DOE invests in developing depleted uranium shielded containers instead of disposal, a long-term solution to the UF{sub 6} problem is attained at comparable or lower cost than disposal as a waste. Two concepts for depleted uranium storage casks were considered in these studies. The first is based on standard fabrication concepts previously developed for depleted uranium metal. The second converts the UF{sub 6} to an oxide aggregate that is used in concrete to make dry storage casks.

  16. A new definition of maternal depletion syndrome.

    PubMed Central

    Winkvist, A; Rasmussen, K M; Habicht, J P

    1992-01-01

    BACKGROUND. Although the term "maternal depletion syndrome" has been commonly used to explain poor maternal and infant health, whether such a syndrome actually exists remains unclear. This uncertainty may be due to the lack of a clear definition of the syndrome and the absence of theoretical frameworks that account for the many factors related to reproductive nutrition. METHODS. We propose a new definition of maternal depletion syndrome within a framework that accounts for potential confounding factors. RESULTS. Our conceptual framework distinguishes between childbearing pattern and inadequate diet as causes of poor maternal health; hence, our definition of maternal depletion syndrome has both biological and practical meaning. The new definition is based on overall change in maternal nutritional status over one reproductive cycle in relation to possible depletion and repletion phases and in relation to initial nutritional status. CONCLUSIONS. The empirical application of this approach should permit the testing of the existence of maternal depletion syndrome in the developing world, and the distinction between populations where family planning will alleviate maternal depletion and those in which an improved diet is also necessary. PMID:1566948

  17. The influence of fog parameters on aerosol depletion measured in the KAEVER experiments

    SciTech Connect

    Poss, G.; Weber, D.; Fritsche, B.

    1995-12-31

    The release of radioactive aerosols in the environment is one of the most serious hazards in case of an accident in nuclear power plant. Many efforts have been made in the past in numerous experimental programs like NSPP, DEMONA, VANAM, LACE, MARVIKEN, others are still underway to improve the knowledge of the aerosol behavior and depletion in a reactor containment in order to estimate the possible source term and to validate computer codes. In the German single compartment KAEVER facility the influence of size distribution, morphology, composition and solubility on the aerosol behavior is investigated. One of the more specific items is to learn about {open_quotes}wet depletion{close_quotes} means, the aerosol depletion behavior in condensing atmospheres. There are no experiments known where the fog parameters like droplet size distribution, volume concentration, respectively airborne liquid water content have been measured in- and on-line explicitly. To the authors knowledge the use of the Battelle FASP photometer, which was developed especially for this reason, for the first time gives insight in condensation behavior under accident typical thermal hydraulic conditions. It delivers a basis for code validation in terms of a real comparison of measurements and calculations. The paper presents results from {open_quotes}wet depletion{close_quotes} aerosol experiments demonstrating how depletion velocity depends on the fog parameters and where obviously critical fog parameter seem to change the regime from a {open_quotes}pseudo dry depletion{close_quotes} at a relative humidity of 100% but quasi no or very low airborne liquid water content to a real {open_quotes}wet depletion{close_quotes} under the presence of fogs with varying densities. Characteristics are outlined how soluble and insoluble particles as well as aerosol mixtures behave under condensing conditions.

  18. SCALE Continuous-Energy Monte Carlo Depletion with Parallel KENO in TRITON

    SciTech Connect

    Goluoglu, Sedat; Bekar, Kursat B; Wiarda, Dorothea

    2012-01-01

    The TRITON sequence of the SCALE code system is a powerful and robust tool for performing multigroup (MG) reactor physics analysis using either the 2-D deterministic solver NEWT or the 3-D Monte Carlo transport code KENO. However, as with all MG codes, the accuracy of the results depends on the accuracy of the MG cross sections that are generated and/or used. While SCALE resonance self-shielding modules provide rigorous resonance self-shielding, they are based on 1-D models and therefore 2-D or 3-D effects such as heterogeneity of the lattice structures may render final MG cross sections inaccurate. Another potential drawback to MG Monte Carlo depletion is the need to perform resonance self-shielding calculations at each depletion step for each fuel segment that is being depleted. The CPU time and memory required for self-shielding calculations can often eclipse the resources needed for the Monte Carlo transport. This summary presents the results of the new continuous-energy (CE) calculation mode in TRITON. With the new capability, accurate reactor physics analyses can be performed for all types of systems using the SCALE Monte Carlo code KENO as the CE transport solver. In addition, transport calculations can be performed in parallel mode on multiple processors.

  19. Depletion sensitivity predicts unhealthy snack purchases.

    PubMed

    Salmon, Stefanie J; Adriaanse, Marieke A; Fennis, Bob M; De Vet, Emely; De Ridder, Denise T D

    2016-01-01

    The aim of the present research is to examine the relation between depletion sensitivity - a novel construct referring to the speed or ease by which one's self-control resources are drained - and snack purchase behavior. In addition, interactions between depletion sensitivity and the goal to lose weight on snack purchase behavior were explored. Participants included in the study were instructed to report every snack they bought over the course of one week. The dependent variables were the number of healthy and unhealthy snacks purchased. The results of the present study demonstrate that depletion sensitivity predicts the amount of unhealthy (but not healthy) snacks bought. The more sensitive people are to depletion, the more unhealthy snacks they buy. Moreover, there was some tentative evidence that this relation is more pronounced for people with a weak as opposed to a strong goal to lose weight, suggesting that a strong goal to lose weight may function as a motivational buffer against self-control failures. All in all, these findings provide evidence for the external validity of depletion sensitivity and the relevance of this construct in the domain of eating behavior. PMID:26321417

  20. The modality effect of ego depletion: Auditory task modality reduces ego depletion.

    PubMed

    Li, Qiong; Wang, Zhenhong

    2016-08-01

    An initial act of self-control that impairs subsequent acts of self-control is called ego depletion. The ego depletion phenomenon has been observed consistently. The modality effect refers to the effect of the presentation modality on the processing of stimuli. The modality effect was also robustly found in a large body of research. However, no study to date has examined the modality effects of ego depletion. This issue was addressed in the current study. In Experiment 1, after all participants completed a handgrip task, one group's participants completed a visual attention regulation task and the other group's participants completed an auditory attention regulation task, and then all participants again completed a handgrip task. The ego depletion phenomenon was observed in both the visual and the auditory attention regulation task. Moreover, participants who completed the visual task performed worse on the handgrip task than participants who completed the auditory task, which indicated that there was high ego depletion in the visual task condition. In Experiment 2, participants completed an initial task that either did or did not deplete self-control resources, and then they completed a second visual or auditory attention control task. The results indicated that depleted participants performed better on the auditory attention control task than the visual attention control task. These findings suggest that altering task modality may reduce ego depletion. PMID:27241617

  1. Neutral depletion and the helicon density limit

    SciTech Connect

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup −3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 μs. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  2. Global Warming: Lessons from Ozone Depletion

    NASA Astrophysics Data System (ADS)

    Hobson, Art

    2010-11-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of Arkansas have developed a conceptual understanding of energy and of electromagnetism, including the electromagnetic spectrum, I devote a lecture (and a textbook section) to ozone depletion and another lecture (and section) to global warming. Humankind came together in 1986 and quickly solved, to the extent that humans can solve it, ozone depletion. We could do the same with global warming, but we haven't and as yet there's no sign that we will. The parallel between the ozone and global warming cases, and the difference in outcomes, are striking and instructive.

  3. Ozone depletion and chlorine loading potentials

    NASA Technical Reports Server (NTRS)

    Pyle, John A.; Wuebbles, Donald J.; Solomon, Susan; Zvenigorodsky, Sergei; Connell, Peter; Ko, Malcolm K. W.; Fisher, Donald A.; Stordal, Frode; Weisenstein, Debra

    1991-01-01

    The recognition of the roles of chlorine and bromine compounds in ozone depletion has led to the regulation or their source gases. Some source gases are expected to be more damaging to the ozone layer than others, so that scientific guidance regarding their relative impacts is needed for regulatory purposes. Parameters used for this purpose include the steady-state and time-dependent chlorine loading potential (CLP) and the ozone depletion potential (ODP). Chlorine loading potentials depend upon the estimated value and accuracy of atmospheric lifetimes and are subject to significant (approximately 20-50 percent) uncertainties for many gases. Ozone depletion potentials depend on the same factors, as well as the evaluation of the release of reactive chlorine and bromine from each source gas and corresponding ozone destruction within the stratosphere.

  4. Applications of a Monte Carlo whole-core microscopic depletion method

    SciTech Connect

    Hutton, J.L.; Butement, A.W.; Watt, S.; Shadbolt, R.D.

    1995-12-31

    In the WIMS-6 (Ref. 1) reactor physics program scheme a three-dimensional microscopic depletion method has been developed using Monte Carlo fluxes. Together with microscopic cross sections, these give nuclide reaction rates, which are used to solve nuclide depletion equations for each region. An extension of the method, enabling rapid whole-core calculations, has been implemented in the long-established companion code MONK5W. Predictions at successive depletion time steps are based on a calculational route where both geometry and cross sections are accurately represented, providing a reliable and independent approach for benchmarking other methods. Newly developed tracking and storage procedures in MONK5W enable whole core burnup modeling on a desktop computer. Theory and applications are presented in this paper.

  5. “When the going gets tough, who keeps going?” Depletion sensitivity moderates the ego-depletion effect

    PubMed Central

    Salmon, Stefanie J.; Adriaanse, Marieke A.; De Vet, Emely; Fennis, Bob M.; De Ridder, Denise T. D.

    2014-01-01

    Self-control relies on a limited resource that can get depleted, a phenomenon that has been labeled ego-depletion. We argue that individuals may differ in their sensitivity to depleting tasks, and that consequently some people deplete their self-control resource at a faster rate than others. In three studies, we assessed individual differences in depletion sensitivity, and demonstrate that depletion sensitivity moderates ego-depletion effects. The Depletion Sensitivity Scale (DSS) was employed to assess depletion sensitivity. Study 1 employs the DSS to demonstrate that individual differences in sensitivity to ego-depletion exist. Study 2 shows moderate correlations of depletion sensitivity with related self-control concepts, indicating that these scales measure conceptually distinct constructs. Study 3 demonstrates that depletion sensitivity moderates the ego-depletion effect. Specifically, participants who are sensitive to depletion performed worse on a second self-control task, indicating a stronger ego-depletion effect, compared to participants less sensitive to depletion. PMID:25009523

  6. Codes with special correlation.

    NASA Technical Reports Server (NTRS)

    Baumert, L. D.

    1964-01-01

    Uniform binary codes with special correlation including transorthogonality and simplex code, Hadamard matrices and difference sets uniform binary codes with special correlation including transorthogonality and simplex code, Hadamard matrices and difference sets

  7. NON-OZONE DEPLETING MOBILE HEAT PUMP

    EPA Science Inventory

    To address the growing environmental and logistical burden posed by continued use of Class I ozone depleting chemicals (ODCs), this co-funded Environmental Security Technology Certification Program (ESTCP) and United States Air Force (USAF) Science and Technology project sought t...

  8. Platelet depletion and severity of streptococcal endocarditis

    PubMed Central

    Dall, Lawrence; Miller, Todd; Herndon, Betty; Diez, Ireneo; Dew, Michelle

    1998-01-01

    OBJECTIVE: To evaluate the importance of thrombocytopenia in streptococcal endocarditis using an animal model. DESIGN: A model of human septic endocarditis was established in rats (polyethylene catheters across the aortic valve and administration of Streptococcus sanguis, 5×107 colony forming units [cfu] intravenous). Thrombocytopenia at four levels was produced by antiplatelet serum. Secondary methods of producing thrombocytopenia were also evaluated. At sacrifice (96 h after platelet depletion and 72 h after infection), vegetations were removed, weighed, diluted, plated and counted. Potential mechanisms of the dose-response relationship between vegetation density and platelet count were evaluated. SETTING: Controlled research laboratory experiments. POPULATION STUDIED: Animal models of streptococcal endocarditis. MAIN RESULTS: The bacterial density of the aortic valve vegetations significantly increased as the platelet count decreased (P=0.0007). In severely thrombocytopenic animals (two-dose antiplatelet serum), data suggest increased vegetation embolism. Platelet depletion, which was minimal with chemical methods, was produced most effectively by antithrombocyte serum. Platelet surfaces in endocarditis were found to express elevated CD62p proteins (72.7% endocarditis, 34.7% control). Platelet protein fractions were evaluated in vitro by both streptocidal (P=0.19) and phagocytosis-stimulating assays. Platelet presence in mature aortic valve vegetations averaged only about 2%. CONCLUSIONS: In platelet depletion experiments using a rat model, a dose-response relationship of peripheral circulating platelet depletion to aortic valve vegetation density was found. The mechanism relating thrombocytopenia to endocarditis severity remains unresolved. PMID:22346555

  9. Direct Visualization of an Impurity Depletion Zone

    NASA Technical Reports Server (NTRS)

    Chernov, Alex A.; Garcia-Ruiz, Juan Ma; Thomas, Bill R.

    2000-01-01

    When a crystal incorporates more impurity per unit of its volume than the impurity concentration in solution, the solution in vicinity of the growing crystal is depleted with respect to the impurity I,2. With a stagnant solution, e. g. in microgravity or gels, an impurity depletion zone expands as the crystal grows and results in greater purity in most of the outer portion of the crystal than in the core. Crystallization in gel provides an opportunity to mimic microgravity conditions and visualize the impurity depletion zone. Colorless, transparent apoferritin (M congruent to 450 KDa) crystals were grown in the presence of red holoferritin dimer as a microheterogeneous impurity (M congruent to 900 KDa) within agarose gel by counterdiffusion with Cd(2+) precipitant. Preferential trapping of dimers, (distribution coefficient K = 4 (exp 1,2)) results in weaker red color around the crystals grown in the left tube in the figure as compared to the control middle tube without crystals. The left and the middle tubes contain colored ferritin dimers, the right tube contains colored trimers. The meniscus in the left tube separate gel (below) and liquid solution containing Cd(2+) (above). Similar solutions, though without precipitants, were present on top of the middle and right tube allowing diffusion of dimers and trimers. The area of weaker color intensity around crystals directly demonstrates overlapped impurity depletion zones.

  10. ATMOSPHERIC BENZENE DEPLETION BY SOIL MICROORGANISMS

    EPA Science Inventory

    Gaseous benzene was rapidly depleted in exposure chambers containing viable soils and plants. When separate components of the system were analyzed, no benzene was detected in soils, plants, or water. Soil microorganisms were shown to be responsible for metabolizing benzene, yield...

  11. Global Warming: Lessons from Ozone Depletion

    ERIC Educational Resources Information Center

    Hobson, Art

    2010-01-01

    My teaching and textbook have always covered many physics-related social issues, including stratospheric ozone depletion and global warming. The ozone saga is an inspiring good-news story that's instructive for solving the similar but bigger problem of global warming. Thus, as soon as students in my physics literacy course at the University of…

  12. Dissolution Treatment of Depleted Uranium Waste

    SciTech Connect

    Gates-Anderson, D D; Laue, C A; Fitch, T E

    2004-02-09

    Researchers at LLNL have developed a 3-stage process that converts pyrophoric depleted uranium metal turnings to a solidified final product that can be transported to and buried at a permitted land disposal site. The three process stages are: (1) pretreatment; (2) dissolution; and (3) solidification. Each stage was developed following extensive experimentation. This report presents the results of their experimental studies.

  13. Demonstration of jackhammer incorporating depleted uranium

    SciTech Connect

    Fischer, L E; Hoard, R W; Carter, D L; Saculla, M D; Wilson, G V

    2000-04-01

    The United States Government currently has an abundance of depleted uranium (DU). This surplus of about 1 billion pounds is the result of an enrichment process using gaseous diffusion to produce enriched and depleted uranium. The enriched uranium has been used primarily for either nuclear weapons for the military or nuclear fuel for the commercial power industry. Most of the depleted uranium remains at the enrichment process plants in the form of depleted uranium hexafluoride (DUF{sub 6}). The Department of Energy (DOE) recently began a study to identify possible commercial applications for the surplus material. One of these potential applications is to use the DU in high-density strikers/hammers in pneumatically driven tools, such as jack hammers and piledrivers to improve their impulse performance. The use of DU could potentially increase tunneling velocity and excavation into target materials with improved efficiency. This report describes the efforts undertaken to analyze the particulars of using DU in two specific striking applications: the jackhammer and chipper tool.

  14. Error-correction coding

    NASA Technical Reports Server (NTRS)

    Hinds, Erold W. (Principal Investigator)

    1996-01-01

    This report describes the progress made towards the completion of a specific task on error-correcting coding. The proposed research consisted of investigating the use of modulation block codes as the inner code of a concatenated coding system in order to improve the overall space link communications performance. The study proposed to identify and analyze candidate codes that will complement the performance of the overall coding system which uses the interleaved RS (255,223) code as the outer code.

  15. How Depleted is the MORB mantle?

    NASA Astrophysics Data System (ADS)

    Hofmann, A. W.; Hart, S. R.

    2015-12-01

    Knowledge of the degree of mantle depletion of highly incompatible elements is critically important for assessing Earth's internal heat production and Urey number. Current views of the degree of MORB source depletion are dominated by Salters and Stracke (2004), and Workman and Hart (2005). The first is based on an assessment of average MORB compositions, whereas the second considers trace element data of oceanic peridotites. Both require an independent determination of one absolute concentration, Lu (Salters & Stracke), or Nd (Workman & Hart). Both use parent-daughter ratios Lu/Hf, Sm/Nd, and Rb/Sr calculated from MORB isotopes combined with continental-crust extraction models, as well as "canonical" trace element ratios, to boot-strap the full range of trace element abundances. We show that the single most important factor in determining the ultimate degree of incompatible element depletion in the MORB source lies in the assumptions about the timing of continent extraction, exemplified by continuous extraction versus simple two-stage models. Continued crust extraction generates additional, recent mantle depletion, without affecting the isotopic composition of the residual mantle significantly. Previous emphasis on chemical compositions of MORB and/or peridotites has tended to obscure this. We will explore the effect of different continent extraction models on the degree of U, Th, and K depletion in the MORB source. Given the uncertainties of the two most popular models, the uncertainties of U and Th in DMM are at least ±50%, and this impacts the constraints on the terrestrial Urey ratio. Salters, F.J.M. and Stracke, A., 2004, Geochem. Geophys. Geosyst. 5, Q05004. Workman, R.K. and Hart, S.R., 2005, EPSL 231, 53-72.

  16. A worldwide view of groundwater depletion

    NASA Astrophysics Data System (ADS)

    van Beek, L. P.; Wada, Y.; van Kempen, C.; Reckman, J. W.; Vasak, S.; Bierkens, M. F.

    2010-12-01

    During the last decades, global water demand has increased two-fold due to increasing population, expanding irrigated area and economic development. Globally such demand can be met by surface water availability (i.e., water in rivers, lakes and reservoirs) but regional variations are large and the absence of sufficient rainfall and run-off increasingly encourages the use of groundwater resources, particularly in the (semi-)arid regions of the world. Excessive abstraction for irrigation frequently leads to overexploitation, i.e. if groundwater abstraction exceeds the natural groundwater recharge over extensive areas and prolonged times, persistent groundwater depletion may occur. Observations and various regional studies have revealed that groundwater depletion is a substantial issue in regions such as Northwest India, Northeast Pakistan, Central USA, Northeast China and Iran. Here we provide a global overview of groundwater depletion from the year 1960 to 2000 at a spatial resolution of 0.5 degree by assessing groundwater recharge with the global hydrological model PCR-GLOBWB and subtracting estimates of groundwater abstraction obtained from IGRAC-GGIS database. PCR-GLOBWB was forced by the CRU climate dataset downscaled to daily time steps using ERA40 re-analysis data. PCR-GLOBWB simulates daily global groundwater recharge (0.5 degree) while considering sub-grid variability of each grid cell (e.g., short and tall vegetation, different soil types, fraction of saturated soil). Country statistics of groundwater abstraction were downscaled to 0.5 degree by using water demand (i.e., agriculture, industry and domestic) as a proxy. To limit problems related to increased capture of discharge and increased recharge due to groundwater pumping, we restricted our analysis to sub-humid to arid areas. The uncertainty in the resulting estimates was assessed by a Monte Carlo analysis of 100 realizations of groundwater recharge and 100 realizations of groundwater abstraction

  17. 26 CFR 1.613-7 - Application of percentage depletion rates provided in section 613(b) to certain taxable years...

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... property shall have the same meaning as those terms are used in 26 CFR (1939) 39.23(m)-1 (Regulations 118... by section 113(b)(1) of the Internal Revenue Code of 1939 and 26 CFR (1939) 39.113(b)(1)-1(c... depletion rate specified in section 613 in respect of any mineral property (within the meaning of the...

  18. 26 CFR 1.613-7 - Application of percentage depletion rates provided in section 613(b) to certain taxable years...

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... property shall have the same meaning as those terms are used in 26 CFR (1939) 39.23(m)-1 (Regulations 118... by section 113(b)(1) of the Internal Revenue Code of 1939 and 26 CFR (1939) 39.113(b)(1)-1(c... depletion rate specified in section 613 in respect of any mineral property (within the meaning of the...

  19. 26 CFR 1.613-7 - Application of percentage depletion rates provided in section 613(b) to certain taxable years...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TAXES (CONTINUED) Natural Resources § 1.613-7 Application of percentage depletion rates provided in... property shall have the same meaning as those terms are used in 26 CFR (1939) 39.23(m)-1 (Regulations 118... by section 113(b)(1) of the Internal Revenue Code of 1939 and 26 CFR (1939)...

  20. Replacements For Ozone-Depleting Foaming Agents

    NASA Technical Reports Server (NTRS)

    Blevins, Elana; Sharpe, Jon B.

    1995-01-01

    Fluorinated ethers used in place of chlorofluorocarbons and hydrochlorofluorocarbons. Replacement necessary because CFC's and HCFC's found to contribute to depletion of ozone from upper atmosphere, and manufacture and use of them by law phased out in near future. Two fluorinated ethers do not have ozone-depletion potential and used in existing foam-producing equipment, designed to handle liquid blowing agents soluble in chemical ingredients that mixed to make foam. Any polyurethane-based foams and several cellular plastics blown with these fluorinated ethers used in processes as diverse as small batch pours, large sprays, or double-band lamination to make insulation for private homes, commercial buildings, shipping containers, and storage tanks. Fluorinated ethers proved useful as replacements for CFC refrigerants and solvents.

  1. Tritium transport vessel using depleted uranium

    SciTech Connect

    Heung, L.K.

    1995-10-01

    A tritium transport vessel using depleted uranium was tested in the laboratory using deuterium and protium. The vessel contains 0.5 kg of depleted uranium and can hold up to 18 grams of tritium. The conditions for activation, tritium loading and tritium unloading were defined. The safety aspects that included air-ingress, tritium diffusion, temperature and pressure potentials were evaluated. Air ingress did not cause any temperature surge when the uranium was fully hydrided, but created a temperature peak of 200 {degree}C when the uranium was dehydrided. Accumulation of non-reactive gases such as argon and moisture in the air blocked further air ingress. Only a flow-through type of air ingress could damage the vessel. 6 refs., 9 figs.

  2. Assessment of Preferred Depleted Uranium Disposal Forms

    SciTech Connect

    Croff, A.G.; Hightower, J.R.; Lee, D.W.; Michaels, G.E.; Ranek, N.L.; Trabalka, J.R.

    2000-06-01

    The Department of Energy (DOE) is in the process of converting about 700,000 metric tons (MT) of depleted uranium hexafluoride (DUF6) containing 475,000 MT of depleted uranium (DU) to a stable form more suitable for long-term storage or disposal. Potential conversion forms include the tetrafluoride (DUF4), oxide (DUO2 or DU3O8), or metal. If worthwhile beneficial uses cannot be found for the DU product form, it will be sent to an appropriate site for disposal. The DU products are considered to be low-level waste (LLW) under both DOE orders and Nuclear Regulatory Commission (NRC) regulations. The objective of this study was to assess the acceptability of the potential DU conversion products at potential LLW disposal sites to provide a basis for DOE decisions on the preferred DU product form and a path forward that will ensure reliable and efficient disposal.

  3. Endoplasmic-Reticulum Calcium Depletion and Disease

    PubMed Central

    Mekahli, Djalila; Bultynck, Geert; Parys, Jan B.; De Smedt, Humbert; Missiaen, Ludwig

    2011-01-01

    The endoplasmic reticulum (ER) as an intracellular Ca2+ store not only sets up cytosolic Ca2+ signals, but, among other functions, also assembles and folds newly synthesized proteins. Alterations in ER homeostasis, including severe Ca2+ depletion, are an upstream event in the pathophysiology of many diseases. On the one hand, insufficient release of activator Ca2+ may no longer sustain essential cell functions. On the other hand, loss of luminal Ca2+ causes ER stress and activates an unfolded protein response, which, depending on the duration and severity of the stress, can reestablish normal ER function or lead to cell death. We will review these various diseases by mainly focusing on the mechanisms that cause ER Ca2+ depletion. PMID:21441595

  4. Copenhagen delegates advance phaseout of ozone depleters

    SciTech Connect

    Kirschner, E.

    1992-12-09

    As expected, delegates at the United Nations Ozone Layer Conference in Copenhagen sped up ozone depleter phaseouts from the 1987 Montreal Protocol and the 1990 London amendments. The changes bring the worldwide production phaseout of chlorofluorocarbons (CFCs) and other ozone depleters in developed countries in line with U.S. and European plans announced earlier this year. Adjustments to the protocol, which are binding on the signatories, change the phaseout for CFC, carbon tetrachloride, and methyl chloroform production and consumption to January 1, 1996 from 2000. The 75% reduction of 1986 levels from CFCs by January 1, 1994 is a compromise between European pressure for an 85% cut and the US goal of 70%. Halon production is to end January 1, 1994, as anticipated. Developing countries continue to have a 10-year grace period. Friends of the Earth ozone campaign director Liz Cook counters that the phaseout dates were scheduled with concern for the chemical industry, not for the ozone layer.

  5. Altitude latitude mapping of plasma depletions

    NASA Astrophysics Data System (ADS)

    Rajesh, P.; Liu, J.; Sinha, H.; Banerje, S.

    2007-12-01

    Plasma depletions, if generated at the geomagnetic equator, are expected to appear in the all sky images as dark bands extending pole ward. The all sky observations conducted from Kavalur (12.5¢ªN, 78.8¢ªE; 4.6¢ªN, geomagnetic), INDIA, but showed dark patches in 630.0 nm entering the imager field of view (FOV) from the northern edge in the post-sunset period. These patches gradually extended towards equator and became fully extended dark bands in the North-South direction by midnight. The series of such images appeared to be the airglow signatures of irregularities that are probably generated at off-equatorial latitudes and mapped to the lower or equatorial latitudes. Similar features were observed in several nights. This appearance of depletions as dark patches from the northern edge of the FOV is explained in this work

  6. The ultimate disposition of depleted uranium

    SciTech Connect

    Lemons, T.R.

    1991-12-31

    Depleted uranium (DU) is produced as a by-product of the uranium enrichment process. Over 340,000 MTU of DU in the form of UF{sub 6} have been accumulated at the US government gaseous diffusion plants and the stockpile continues to grow. An overview of issues and objectives associated with the inventory management and the ultimate disposition of this material is presented.

  7. The ultimate disposition of depleted uranium

    SciTech Connect

    Not Available

    1990-12-01

    Significant amounts of the depleted uranium (DU) created by past uranium enrichment activities have been sold, disposed of commercially, or utilized by defense programs. In recent years, however, the demand for DU has become quite small compared to quantities available, and within the US Department of Energy (DOE) there is concern for any risks and/or cost liabilities that might be associated with the ever-growing inventory of this material. As a result, Martin Marietta Energy Systems, Inc. (Energy Systems), was asked to review options and to develop a comprehensive plan for inventory management and the ultimate disposition of DU accumulated at the gaseous diffusion plants (GDPs). An Energy Systems task team, under the chairmanship of T. R. Lemons, was formed in late 1989 to provide advice and guidance for this task. This report reviews options and recommends actions and objectives in the management of working inventories of partially depleted feed (PDF) materials and for the ultimate disposition of fully depleted uranium (FDU). Actions that should be considered are as follows. (1) Inspect UF{sub 6} cylinders on a semiannual basis. (2) Upgrade cylinder maintenance and storage yards. (3) Convert FDU to U{sub 3}O{sub 8} for long-term storage or disposal. This will include provisions for partial recovery of costs to offset those associated with DU inventory management and the ultimate disposal of FDU. Another recommendation is to drop the term tails'' in favor of depleted uranium'' or DU'' because the tails'' label implies that it is waste.'' 13 refs.

  8. Depletion modeling of liquid dominated geothermal reservoirs

    SciTech Connect

    Olsen, G.

    1984-06-01

    Depletion models for liquid-dominated geothermal reservoirs are derived and presented. The depletion models are divided into two categories: confined and unconfined. For both cases depletion models with no recharge (or influx), and depletion models including recharge, are used to match field data from the Svartsengi high temperature geothermal field in Iceland. The influx models included with the mass and energy balances are adopted from the petroleum engineering literature. The match to production data from Svartsengi is improved when influx was included. The Schilthuis steady-state influx gives a satisfactory match. The finite aquifer method of Fetkovitch, and the unsteady state method of Hurst gave reasonable answers, but not as good. The best match is obtained using Hurst simplified solution when lambda = 1.3 x 10{sup -4} m{sup -1}. From the match the cross-sectional area of the aquifer was calculated as 3.6 km{sup 2}. The drawdown was predicted using the Hurst simplified method, and compared with predicted drawdown from a boiling model and an empirical log-log model. A large difference between the models was obtained. The predicted drawdown using the Hurst simplified method falls between the other two. Injection has been considered by defining the net rate as being the production rate minus the injection rate. No thermal of transient effects were taken into account. Prediction using three different net rates shows that the pressure can be maintained using the Hurst simplified method if there is significant fluid reinjection. 32 refs., 44 figs., 2 tabs.

  9. Carbon sequestration in depleted oil shale deposits

    SciTech Connect

    Burnham, Alan K; Carroll, Susan A

    2014-12-02

    A method and apparatus are described for sequestering carbon dioxide underground by mineralizing the carbon dioxide with coinjected fluids and minerals remaining from the extraction shale oil. In one embodiment, the oil shale of an illite-rich oil shale is heated to pyrolyze the shale underground, and carbon dioxide is provided to the remaining depleted oil shale while at an elevated temperature. Conditions are sufficient to mineralize the carbon dioxide.

  10. Pumping test evaluation of stream depletion parameters.

    PubMed

    Lough, Hilary K; Hunt, Bruce

    2006-01-01

    Descriptions are given of a pumping test and a corresponding analysis that permit calculation of all five hydrogeological parameters appearing in the Hunt (2003) solution for stream depletion caused by ground water abstraction from a well beside a stream. This solution assumes that flow in the pumped aquifer is horizontal, flow in the overlying aquitard or system of aquitards is vertical, and the free surface in the top aquitard is allowed to draw down. The definition of an aquitard in this paper is any layer with a vertical hydraulic conductivity much lower than the horizontal hydraulic conductivity of the pumped aquifer. These "aquitards" may be reasonably permeable layers but are distinguished from the pumped aquifer by their hydraulic conductivity contrast. The pumping test requires a complete set of drawdown measurements from at least one observation well. This well must be deep enough to penetrate the pumped aquifer, and pumping must continue for a sufficient time to ensure that depleted streamflow becomes a significant portion of the well abstraction rate. Furthermore, two of the five parameters characterize an aquitard that overlies the pumped aquifer, and values for these parameters are seen to be dependent upon the initial water table elevation in the aquitard. The field test analyzed herein used a total of eight observation wells screened in the pumped aquifer, and measurements from these wells gave eight sets of parameters that are used in a sensitivity analysis to determine the relative importance of each parameter in the stream depletion calculations. PMID:16857031

  11. Record Arctic ozone depletion could occur again

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-02-01

    In the winter of 2010-2011, ozone levels above the Arctic declined to record lows, creating the first Arctic ozone hole, similar to the well-known Antarctic ozone hole. Scientists believe the ozone depletion was due partly to unusually cold temperatures in the stratosphere above the Arctic, as colder stratospheric temperatures make ozone-destroying chemicals such as chlorine more active. As global climate change continues, the Arctic stratosphere is expected to get colder, but levels of ozone-destroying chemicals should decline, as emissions of these chemicals were banned by the Montreal Protocol. To try to learn more about Arctic ozone dynamics and determine whether the Arctic ozone hole is likely to recur, Sinnhuber et al. looked at satellite observations of temperature, ozone, water vapor, and chemicals that affect ozone in the Arctic atmosphere. They also used a model to determine how sensitive ozone levels are to stratospheric temperatures and chemistry. They found that their model accurately reproduced measured conditions. Their model suggests that stratospheric temperatures 1°C lower than in the 2010-2011 winter would result in locally nearly complete ozone depletion in the Arctic lower stratosphere with current levels of chemicals. A 10% reduction in ozone-depleting chemicals would be offset by a 1°C decrease in stratospheric temperatures.

  12. Barium depletion in hollow cathode emitters

    NASA Astrophysics Data System (ADS)

    Polk, James E.; Mikellides, Ioannis G.; Capece, Angela M.; Katz, Ira

    2016-01-01

    Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al2O3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values.

  13. Antarctic springtime depletion of atmospheric mercury.

    PubMed

    Ebinghaus, Ralf; Kock, Hans H; Temme, Christian; Einax, Jürgen W; Lowe, Astrid G; Richter, Andreas; Burrows, John P; Schroeder, William H

    2002-03-15

    Unlike other heavy metals that are inherently associated with atmospheric aerosols, mercury in ambient air exists predominantly in the gaseous elemental form. Because of its prolonged atmospheric residence time, elemental mercury vapor is distributed on a global scale. Recently, Canadian researchers have discovered that total gaseous mercury levels in the lower tropospheric boundary layer in the Canadian Arctic are often significantly depleted during the months after polar sunrise. A possible explanation may involve oxidation of elemental mercury, followed by adsorption and deposition of the oxidized form, leading to an increased input of atmospheric mercury into the Arctic ecosystem. Here we present the first continuous high-time-resolution measurements of total gaseous mercury in the Antarctic covering a 12-month period between January 2000 and January 2001 at the German Antarctic research station Neumayer (70 degrees 39' S, 8 degrees 15' W). We report that mercury depletion events also occur in the Antarctic after polar sunrise and compare our measurements with a data setfrom Alert, Nunavut, Canada. We also present indications that BrO radicals and ozone play a key role in the boundary-layer chemistry during springtime mercury depletion events in the Antarctic troposphere. PMID:11944675

  14. Homological stabilizer codes

    SciTech Connect

    Anderson, Jonas T.

    2013-03-15

    In this paper we define homological stabilizer codes on qubits which encompass codes such as Kitaev's toric code and the topological color codes. These codes are defined solely by the graphs they reside on. This feature allows us to use properties of topological graph theory to determine the graphs which are suitable as homological stabilizer codes. We then show that all toric codes are equivalent to homological stabilizer codes on 4-valent graphs. We show that the topological color codes and toric codes correspond to two distinct classes of graphs. We define the notion of label set equivalencies and show that under a small set of constraints the only homological stabilizer codes without local logical operators are equivalent to Kitaev's toric code or to the topological color codes. - Highlights: Black-Right-Pointing-Pointer We show that Kitaev's toric codes are equivalent to homological stabilizer codes on 4-valent graphs. Black-Right-Pointing-Pointer We show that toric codes and color codes correspond to homological stabilizer codes on distinct graphs. Black-Right-Pointing-Pointer We find and classify all 2D homological stabilizer codes. Black-Right-Pointing-Pointer We find optimal codes among the homological stabilizer codes.

  15. Depleted uranium residual radiological risk assessment for Kosovo sites.

    PubMed

    Durante, Marco; Pugliese, Mariagabriella

    2003-01-01

    During the recent conflict in Yugoslavia, depleted uranium rounds were employed and were left in the battlefield. Health concern is related to the risk arising from contamination of areas in Kosovo with depleted uranium penetrators and dust. Although chemical toxicity is the most significant health risk related to uranium, radiation exposure has been allegedly related to cancers among veterans of the Balkan conflict. Uranium munitions are considered to be a source of radiological contamination of the environment. Based on measurements and estimates from the recent Balkan Task Force UNEP mission in Kosovo, we have estimated effective doses to resident populations using a well-established food-web mathematical model (RESRAD code). The UNEP mission did not find any evidence of widespread contamination in Kosovo. Rather than the actual measurements, we elected to use a desk assessment scenario (Reference Case) proposed by the UNEP group as the source term for computer simulations. Specific applications to two Kosovo sites (Planeja village and Vranovac hill) are described. Results of the simulations suggest that radiation doses from water-independent pathways are negligible (annual doses below 30 microSv). A small radiological risk is expected from contamination of the groundwater in conditions of effective leaching and low distribution coefficient of uranium metal. Under the assumptions of the Reference Case, significant radiological doses (>1 mSv/year) might be achieved after many years from the conflict through water-dependent pathways. Even in this worst-case scenario, DU radiological risk would be far overshadowed by its chemical toxicity. PMID:12500808

  16. CESAR: A Code for Nuclear Fuel and Waste Characterisation

    SciTech Connect

    Vidal, J.M.; Grouiller, J.P.; Launay, A.; Berthion, Y.; Marc, A.; Toubon, H.

    2006-07-01

    CESAR (Simplified Evolution Code Applied to Reprocessing) is a depletion code developed through a joint program between CEA and COGEMA. In the late 1980's, the first use of this code dealt with nuclear measurement at the Laboratories of the La Hague reprocessing plant. The use of CESAR was then extended to characterizations of all entrance materials and for characterisation, via tracer, of all produced waste. The code can distinguish more than 100 heavy nuclides, 200 fission products and 100 activation products, and it can characterise both the fuel and the structural material of the fuel. CESAR can also make depletion calculations from 3 months to 1 million years of cooling time. Between 2003-2005, the 5. version of the code was developed. The modifications were related to the harmonisation of the code's nuclear data with the JEF2.2 nuclear data file. This paper describes the code and explains the extensive use of this code at the La Hague reprocessing plant and also for prospective studies. The second part focuses on the modifications of the latest version, and describes the application field and the qualification of the code. Many companies and the IAEA use CESAR today. CESAR offers a Graphical User Interface, which is very user-friendly. (authors)

  17. Coding of Neuroinfectious Diseases.

    PubMed

    Barkley, Gregory L

    2015-12-01

    Accurate coding is an important function of neurologic practice. This contribution to Continuum is part of an ongoing series that presents helpful coding information along with examples related to the issue topic. Tips for diagnosis coding, Evaluation and Management coding, procedure coding, or a combination are presented, depending on which is most applicable to the subject area of the issue. PMID:26633789

  18. Model Children's Code.

    ERIC Educational Resources Information Center

    New Mexico Univ., Albuquerque. American Indian Law Center.

    The Model Children's Code was developed to provide a legally correct model code that American Indian tribes can use to enact children's codes that fulfill their legal, cultural and economic needs. Code sections cover the court system, jurisdiction, juvenile offender procedures, minor-in-need-of-care, and termination. Almost every Code section is…

  19. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  20. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2012-04-01 2012-04-01 false Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  1. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...,” and “minerals,” see paragraph (d) of § 1.611-1. (b) Denial of percentage depletion in case of oil and... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Percentage depletion; general rule. 1.613-1... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  2. Children's Models of the Ozone Layer and Ozone Depletion.

    ERIC Educational Resources Information Center

    Christidou, Vasilia; Koulaidis, Vasilis

    1996-01-01

    The views of 40 primary students on ozone and its depletion were recorded through individual, semi-structured interviews. The data analysis resulted in the formation of a limited number of models concerning the distribution and role of ozone in the atmosphere, the depletion process, and the consequences of ozone depletion. Identifies five target…

  3. 26 CFR 1.642(e)-1 - Depreciation and depletion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 8 2010-04-01 2010-04-01 false Depreciation and depletion. 1.642(e)-1 Section 1... (CONTINUED) INCOME TAXES Estates, Trusts, and Beneficiaries § 1.642(e)-1 Depreciation and depletion. An estate or trust is allowed the deductions for depreciation and depletion, but only to the extent...

  4. [Mitochondrial disease and mitochondrial DNA depletion syndromes].

    PubMed

    Huang, Chin-Chang; Hsu, Chang-Huang

    2009-12-01

    Mitochondria is an intracellular double membrane-bound structure and it can provide energy for intracellular metabolism. The metabolism includes Krebs cycle, beta-oxidation and lipid synthesis. The density of mitochondria is different in various tissues dependent upon the demands of oxidative phosphorylation. Mitochondrial diseases can occur by defects either in mitochondrial DNA or nuclear DNA. Human mitochondrial DNA (mtDNA) encoding for 22 tRNAs, 2 rRNAs and 13 mRNAs that are translated in the mitochondria. Mitochondrial genetic diseases are most resulted from defects in the mtDNA which may be point mutations, deletions, or mitochondrial DNA depletion. These patterns of inheritance in mitochondrial diseases include sporadic, maternally inherited, or of Mendelian inheritance. Mitochondrial DNA depletion is caused by defects in the nuclear genes that are responsible for maintenance of integrity of mtDNA or deoxyribonucelotide pools and mtDNA biogenesis. The mtDNA depletion syndrome (MDS) includes the following categories: progressive external ophthalmoplegia (PEO), predominant myopathy, mitochondrial neurogastrointestinal encephalomyopathy (MNGIE), sensory-ataxic neuropathy, dysarthria, and ophthalmoplegia (SANDO) and hepato-encephalopathy. The most common tissues or organs involved in MDS and related disorders include the brain, liver and muscles. These involved genes are divided into two groups including 1) DNA polymerase gamma (POLG, POLG2) and Twinkle genes whose products function directly at the mtDNA replication fork, and 2) adenine nucleotide translocator 1, thymidine phosphorylase, thymidine kinase 2, deoxyguanosine kinase, ADP-forming succinyl-CoA synthetase ligase, MPV17 whose products supply the mitochondria with deoxyribonucleotide triphosphate pools needed for mtDNA replication, and possible mutation in the RRM2B gene. The development has provided new information about the importance of the biosynthetic pathway of the nucleotides for mtDNA replication

  5. A modern depleted uranium manufacturing facility

    SciTech Connect

    Zagula, T.A.

    1995-07-01

    The Specific Manufacturing Capabilities (SMC) Project located at the Idaho National Engineering Laboratory (INEL) and operated by Lockheed Martin Idaho Technologies Co. (LMIT) for the Department of Energy (DOE) manufactures depleted uranium for use in the U.S. Army MIA2 Abrams Heavy Tank Armor Program. Since 1986, SMC has fabricated more than 12 million pounds of depleted uranium (DU) products in a multitude of shapes and sizes with varying metallurgical properties while maintaining security, environmental, health and safety requirements. During initial facility design in the early 1980`s, emphasis on employee safety, radiation control and environmental consciousness was gaining momentum throughout the DOE complex. This fact coupled with security and production requirements forced design efforts to focus on incorporating automation, local containment and computerized material accountability at all work stations. The result was a fully automated production facility engineered to manufacture DU armor packages with virtually no human contact while maintaining security, traceability and quality requirements. This hands off approach to handling depleted uranium resulted in minimal radiation exposures and employee injuries. Construction of the manufacturing facility was complete in early 1986 with the first armor package certified in October 1986. Rolling facility construction was completed in 1987 with the first certified plate produced in the fall of 1988. Since 1988 the rolling and manufacturing facilities have delivered more than 2600 armor packages on schedule with 100% final product quality acceptance. During this period there was an annual average of only 2.2 lost time incidents and a single individual maximum radiation exposure of 150 mrem. SMC is an example of designing and operating a facility that meets regulatory requirements with respect to national security, radiation control and personnel safety while achieving production schedules and product quality.

  6. Modelling CO depletion in starless cores

    NASA Astrophysics Data System (ADS)

    Rawlings, Jonathan M. C.

    In recent years there has been a dramatic increase in the observational detection of molecular depletion in star-forming dark clouds. In many cases the data is of very high quality and what was once considered a rather hypothetical process is now almost universally accepted as a (the) major cause of the presence of emission 'holes' in molecular maps of dense cores. However, the interpretation of the data can be severely undermined by uncertainties in the physics and chemistry. This is particularly true in the case of general molecular studies of active star-forming regions. For these objects there exist strong degeneracies between various chemical effects (gas-phase time-dependencies, desorption processes and efficiencies, ionization rates etc.) and poorly constrained physics (most particularly in the assumed kinematics and evolutionary history). Whilst these problems result in unacceptable ambiguities in the case of evolved sources, we can make significant progress for young, near-static cores and using molecular species with simple chemistries. A considerable set of constraints on the free parameters is now provided by the extensive sub-millimetre continuum and infra-red absorption studies of starless cores. These observations give us good descriptions of the temperature and density profiles in these sources. Moreover CO is to a large extent chemically inert, so that any decline of abundance at high densities can (primarily) be interpreted as being a consequence of freeze-out. Thus there are only two major free parameters:- the net depletion/desorption rate and the chemical age of the source. In this study CO abundance profiles are calculated as a function of time for cores whose temperature and density profiles have already been determined. The results are corrected for excitation effects and converted to synthetic maps, assuming typical single-dish beam parameters and source characteristics. A strong correlation with existing depletion maps is found and strong

  7. Zn2+ depletion blocks endosome fusion.

    PubMed Central

    Aballay, A; Sarrouf, M N; Colombo, M I; Stahl, P D; Mayorga, L S

    1995-01-01

    Fusion among endosomes is an important step for transport and sorting of internalized macromolecules. Working in a cell-free system, we previously reported that endosome fusion requires cytosol and ATP, and is sensitive to N-ethylmaleimide. Fusion is regulated by monomeric and heterotrimeric GTP-binding proteins. We now report that fusion can proceed at very low Ca2+ concentrations, i.e. < 30 nM. Moreover, fusion is not affected when intravesicular Ca2+ is depleted by preincubation of vesicles with calcium ionophores (5 microM ionomycin or A23187) in the presence of calcium chelators (5 mM EGTA or 60 mM EDTA). The results indicate that fusion can proceed at extremely low concentrations of intravesicular and extravesicular Ca2+. However, BAPTA [1,2-bis-(o-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid], a relatively specific Ca2+ chelator, inhibits fusion. BAPTA binds other metals besides Ca2+. We present evidence that BAPTA inhibition is due not to Ca2+ chelation but to Zn2+ depletion. TPEN [N,N,N',N'-tetrakis-(2-pyridylmethyl) ethylenediamine], another metal-ion chelator with low affinity for Ca2+, also inhibited fusion. TPEN- and BAPTA-inhibited fusions were restored by addition of Zn2+. Zn(2+)-dependent fusion presents the same characteristics as control fusion. In intact cells, TPEN inhibited transport along the endocytic pathway. The results indicate that Zn2+ depletion blocks endosome fusion, suggesting that this ion is necessary for the function of one or more factors involved in the fusion process. Images Figure 1 PMID:8554539

  8. SVARTSENGI FIELD PRODUCTION DATA AND DEPLETION ANALYSIS

    SciTech Connect

    Gudmundsson, J.S.; Thorhallsson, O.S.

    1985-01-22

    There have been two major high-temperature geothermal field developments in Iceland in the last decade; Krafla in the north-east, and Svartsengi in the south-west. These and other geothermal developments have recently been reported by Palmason et al. The Krafla field will not be discussed here, but details about the field are available in Stefansson and the power plant in Eliasson et al. Several reservoir engineering studies of the Krafla field have been published. The Svartsengi field is one of several fields on the Reykjanes Peninsula in south-west Iceland. About 15 km west of Svartsengi, on the tip of the Peninsula, the Reykjanes field is now under development, primarily for seawater chemicals production. The recently drilled Eldvorp field is located in line between these two fields, about 5 km west of Svartsengi. There are also several fields to the east of Svartsengi, at 15-20 km distance. The Svartsengi, Eldvorp, and Reykjanes fields exist in the same tectonic-volcanic environment, and are surrounded by similar geohydrological conditions, as discussed by Georgsson; see also Gudmundsson et al. and Franzson. Optimum development of these and other fields on the Reykjanes Peninsula, requires an understanding of their depletion behavior with time; that is, how the reservoir pressure falls with production. While recognizing that no two geothermal fields are alike, we also realize that an understanding of the depletion behavior of Svartsengi, for example, may prove useful in the development of other similar and nearby fields. The main purpose of this paper is to report our depletion analysis of the Svartsengi field using lumped-parameter and water influx modeling: we also report the field's production history.

  9. Simulation of polar ozone depletion: An update

    NASA Astrophysics Data System (ADS)

    Solomon, Susan; Kinnison, Doug; Bandoro, Justin; Garcia, Rolando

    2015-08-01

    We evaluate polar ozone depletion chemistry using the specified dynamics version of the Whole Atmosphere Community Climate Model for the year 2011. We find that total ozone depletion in both hemispheres is dependent on cold temperatures (below 192 K) and associated heterogeneous chemistry on polar stratospheric cloud particles. Reactions limited to warmer temperatures above 192 K, or on binary liquid aerosols, yield little modeled polar ozone depletion in either hemisphere. An imposed factor of three enhancement in stratospheric sulfate increases ozone loss by up to 20 Dobson unit (DU) in the Antarctic and 15 DU in the Arctic in this model. Such enhanced sulfate loads are similar to those observed following recent relatively small volcanic eruptions since 2005 and imply impacts on the search for polar ozone recovery. Ozone losses are strongly sensitive to temperature, with a test case cooler by 2 K producing as much as 30 DU additional ozone loss in the Antarctic and 40 DU in the Arctic. A new finding of this paper is the use of the temporal behavior and variability of ClONO2 and HCl as indicators of the efficacy of heterogeneous chemistry. Transport of ClONO2 from the southern subpolar regions near 55-65°S to higher latitudes near 65-75°S provides a flux of NOx from more sunlit latitudes to the edge of the vortex and is important for ozone loss in this model. Comparisons between modeled and observed total column and profile ozone perturbations, ClONO2 abundances, and the rate of change of HCl bolster confidence in these conclusions.

  10. Rhenium Disulfide Depletion-Load Inverter

    NASA Astrophysics Data System (ADS)

    McClellan, Connor; Corbet, Chris; Rai, Amritesh; Movva, Hema C. P.; Tutuc, Emanuel; Banerjee, Sanjay K.

    2015-03-01

    Many semiconducting Transition Metal Dichalcogenide (TMD) materials have been effectively used to create Field-Effect Transistor (FET) devices but have yet to be used in logic designs. We constructed a depletion-load voltage inverter using ultrathin layers of Rhenium Disulfide (ReS2) as the semiconducting channel. This ReS2 inverter was fabricated on a single micromechanically-exfoliated flake of ReS2. Electron beam lithography and physical vapor deposition were used to construct Cr/Au electrical contacts, an Alumina top-gate dielectric, and metal top-gate electrodes. By using both low (Aluminum) and high (Palladium) work-function metals as two separate top-gates on a single ReS2 flake, we create a dual-gated depletion mode (D-mode) and enhancement mode (E-mode) FETs in series. Both FETs displayed current saturation in the output characteristics as a result of the FET ``pinch-off'' mechanism and On/Off current ratios of 105. Field-effect mobilities of 23 and 17 cm2V-1s-1 and subthreshold swings of 97 and 551 mV/decade were calculated for the E-mode and D-mode FETs, respectively. With a supply voltage of 1V, at low/negative input voltages the inverter output was at a high logic state of 900 mV. Conversely with high/positive input voltages, the inverter output was at a low logic state of 500 mV. The inversion of the input signal demonstrates the potential for using ReS2 in future integrated circuit designs and the versatility of depletion-load logic devices for TMD research. NRI SWAN Center and ARL STTR Program.

  11. Capstone Depleted Uranium Aerosols: Generation and Characterization

    SciTech Connect

    Parkhurst, MaryAnn; Szrom, Fran; Guilmette, Ray; Holmes, Tom; Cheng, Yung-Sung; Kenoyer, Judson L.; Collins, John W.; Sanderson, T. Ellory; Fliszar, Richard W.; Gold, Kenneth; Beckman, John C.; Long, Julie

    2004-10-19

    In a study designed to provide an improved scientific basis for assessing possible health effects from inhaling depleted uranium (DU) aerosols, a series of DU penetrators was fired at an Abrams tank and a Bradley fighting vehicle. A robust sampling system was designed to collect aerosols in this difficult environment and continuously monitor the sampler flow rates. Aerosols collected were analyzed for uranium concentration and particle size distribution as a function of time. They were also analyzed for uranium oxide phases, particle morphology, and dissolution in vitro. The resulting data provide input useful in human health risk assessments.

  12. Scientific assessment of ozone depletion: 1991

    NASA Technical Reports Server (NTRS)

    1991-01-01

    Over the past few years, there have been highly significant advances in the understanding of the impact of human activities on the Earth's stratospheric ozone layer and the influence of changes in chemical composition of the radiative balance of the climate system. Specifically, since the last international scientific review (1989), there have been five major advances: (1) global ozone decreases; (2) polar ozone; (3) ozone and industrial halocarbons; (4) ozone and climate relations; and (5) ozone depletion potentials (ODP's) and global warming potentials (GWP's). These topics and others are discussed.

  13. Depletion of the Outer Asteroid Belt

    NASA Technical Reports Server (NTRS)

    Liou, Jer-Chyi; Malhotra, Renu

    1997-01-01

    During the early history of the solar system, it is likely that the outer planets changed their distance from the sun, and hence, their influence on the asteroid belt evolved with time. The gravitational influence of Jupiter and Saturn on the orbital evolution of asteroids in the outer asteroid belt was calculated. The results show that the sweeping of mean motion resonances associated with planetary migration efficiently destabilizes orbits in the outer asteroid belt on a time scale of 10 million years. This mechanism provides an explanation for the observed depletion of asteroids in that region.

  14. Ozone depletion: implications for the veterinarian.

    PubMed

    Kopecky, K E

    1978-09-15

    Man has inadvertently modified the stratosphere. There is a good possibility that the ozone layer is being depleted by the use of jet aircraft (SST), chlorofluoromethane propellants, and nitrogen fertilizers. Under unpolluted conditions, the production of ozone equals its destruction. By man's intervention, however, the destruction may exceed the production. The potential outcome is increased intensity of solar ultraviolet (280-400 nm) radiation and penetration to the earth's surface of previously absorbed wavelengths below about 280 nm. The increased ultraviolet radiation would increase the likelihood of skin cancer in man and ocular squamous cell carcinoma in cattle. The climate also might be modified, possibly in an undesirable way. PMID:568617

  15. Correlation between cosmic rays and ozone depletion.

    PubMed

    Lu, Q-B

    2009-03-20

    This Letter reports reliable satellite data in the period of 1980-2007 covering two full 11-yr cosmic ray (CR) cycles, clearly showing the correlation between CRs and ozone depletion, especially the polar ozone loss (hole) over Antarctica. The results provide strong evidence of the physical mechanism that the CR-driven electron-induced reaction of halogenated molecules plays the dominant role in causing the ozone hole. Moreover, this mechanism predicts one of the severest ozone losses in 2008-2009 and probably another large hole around 2019-2020, according to the 11-yr CR cycle. PMID:19392251

  16. Mesospheric ionization and O2 1Delta(g) depletion

    NASA Technical Reports Server (NTRS)

    Spear, K. A.; Solomon, S.

    1987-01-01

    Observations of O2 1Delta(g) emission during solar proton events reveal large depletions below 80 and near 90 km. The lower-altitude depletions are believed to be due to odd hydrogen production and associated depletion of ozone, but the mechanism producing the depletion near 90 km has not yet been established. In this paper, it is proposed that an exothermic charge exchange reaction between O2(+) and O2 1Delta(g) is likely to be responsible for these high-altitude depletions. In particular, it is shown that the vertical structure of the observed change in airglow emission is consistent with this mechanism.

  17. Accumulate repeat accumulate codes

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative channel coding scheme called 'Accumulate Repeat Accumulate codes' (ARA). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes, thus belief propagation can be used for iterative decoding of ARA codes on a graph. The structure of encoder for this class can be viewed as precoded Repeat Accumulate (RA) code or as precoded Irregular Repeat Accumulate (IRA) code, where simply an accumulator is chosen as a precoder. Thus ARA codes have simple, and very fast encoder structure when they representing LDPC codes. Based on density evolution for LDPC codes through some examples for ARA codes, we show that for maximum variable node degree 5 a minimum bit SNR as low as 0.08 dB from channel capacity for rate 1/2 can be achieved as the block size goes to infinity. Thus based on fixed low maximum variable node degree, its threshold outperforms not only the RA and IRA codes but also the best known LDPC codes with the dame maximum node degree. Furthermore by puncturing the accumulators any desired high rate codes close to code rate 1 can be obtained with thresholds that stay close to the channel capacity thresholds uniformly. Iterative decoding simulation results are provided. The ARA codes also have projected graph or protograph representation that allows for high speed decoder implementation.

  18. Concatenated Coding Using Trellis-Coded Modulation

    NASA Technical Reports Server (NTRS)

    Thompson, Michael W.

    1997-01-01

    In the late seventies and early eighties a technique known as Trellis Coded Modulation (TCM) was developed for providing spectrally efficient error correction coding. Instead of adding redundant information in the form of parity bits, redundancy is added at the modulation stage thereby increasing bandwidth efficiency. A digital communications system can be designed to use bandwidth-efficient multilevel/phase modulation such as Amplitude Shift Keying (ASK), Phase Shift Keying (PSK), Differential Phase Shift Keying (DPSK) or Quadrature Amplitude Modulation (QAM). Performance gain can be achieved by increasing the number of signals over the corresponding uncoded system to compensate for the redundancy introduced by the code. A considerable amount of research and development has been devoted toward developing good TCM codes for severely bandlimited applications. More recently, the use of TCM for satellite and deep space communications applications has received increased attention. This report describes the general approach of using a concatenated coding scheme that features TCM and RS coding. Results have indicated that substantial (6-10 dB) performance gains can be achieved with this approach with comparatively little bandwidth expansion. Since all of the bandwidth expansion is due to the RS code we see that TCM based concatenated coding results in roughly 10-50% bandwidth expansion compared to 70-150% expansion for similar concatenated scheme which use convolution code. We stress that combined coding and modulation optimization is important for achieving performance gains while maintaining spectral efficiency.

  19. Coset Codes Viewed as Terminated Convolutional Codes

    NASA Technical Reports Server (NTRS)

    Fossorier, Marc P. C.; Lin, Shu

    1996-01-01

    In this paper, coset codes are considered as terminated convolutional codes. Based on this approach, three new general results are presented. First, it is shown that the iterative squaring construction can equivalently be defined from a convolutional code whose trellis terminates. This convolutional code determines a simple encoder for the coset code considered, and the state and branch labelings of the associated trellis diagram become straightforward. Also, from the generator matrix of the code in its convolutional code form, much information about the trade-off between the state connectivity and complexity at each section, and the parallel structure of the trellis, is directly available. Based on this generator matrix, it is shown that the parallel branches in the trellis diagram of the convolutional code represent the same coset code C(sub 1), of smaller dimension and shorter length. Utilizing this fact, a two-stage optimum trellis decoding method is devised. The first stage decodes C(sub 1), while the second stage decodes the associated convolutional code, using the branch metrics delivered by stage 1. Finally, a bidirectional decoding of each received block starting at both ends is presented. If about the same number of computations is required, this approach remains very attractive from a practical point of view as it roughly doubles the decoding speed. This fact is particularly interesting whenever the second half of the trellis is the mirror image of the first half, since the same decoder can be implemented for both parts.

  20. Imaging neurotransmitter uptake and depletion in astrocytes

    SciTech Connect

    Tan, W. |; Haydon, P.G.; Yeung, E.S.

    1997-08-01

    An ultraviolet (UV) laser-based optical microscope and charge-coupled device (CCD) detection system was used to obtain chemical images of biological cells. Subcellular structures can be easily seen in both optical and fluorescence images. Laser-induced native fluorescence detection provides high sensitivity and low limits of detection, and it does not require coupling to fluorescent dyes. We were able to quantitatively monitor serotonin that has been taken up into and released from individual astrocytes on the basis of its native fluorescence. Different regions of the cells took up different amounts of serotonin with a variety of uptake kinetics. Similarly, we observed different serotonin depletion dynamics in different astrocyte regions. There were also some astrocyte areas where no serotonin uptake or depletion was observed. Potential applications include the mapping of other biogenic species in cells as well as the ability to image their release from specific regions of cells in response to external stimuli. {copyright} {ital 1997} {ital Society for Applied Spectroscopy}

  1. A critical comparison of ionospheric depletion chemicals

    SciTech Connect

    Bernhardt, P.A. )

    1987-05-01

    Six chemicals, H{sub 2}, H{sub 2}O, CO{sub 2}, SF{sub 6}, CF{sub 3}BR, and Ni(CO){sub 4}, are considered as ionospheric modification agents. Each of these species reacts in the F region to produce localized plasma depletions. The first three interact with O{sup +} and yield polyatomic ions which dissociatively recombine with electrons to give neutrals. The last three dissociatively attach electrons to produce heavy negative ions which become mutually neutralized by reactions with O{sup +}. The effectiveness of these chemicals depends on the amount which goes into the vapor state upon release. Thermodynamic calculations show that H{sub 2}O has the lowest vapor yield of about 20% from a heated, pressurized tank. Over 60% of the other substances should be vented in gaseous form. Based on estimates of plasma density reduction and airglow stimulation, nickel carbonyl is the most efficient of the six species for modifying the nighttime ionosphere. During the daytime, CF{sub 3}BR and SF{sub 6} provide the largest depletions.

  2. Convective Polymer Depletion on Pair Particle Interactions

    NASA Astrophysics Data System (ADS)

    Fan, Tai-Hsi; Taniguchi, Takashi; Tuinier, Remco

    2011-11-01

    Understanding transport, reaction, aggregation, and viscoelastic properties of colloid-polymer mixture is of great importance in food, biomedical, and pharmaceutical sciences. In non-adsorbing polymer solutions, colloidal particles tend to aggregate due to the depletion-induced osmotic or entropic force. Our early development for the relative mobility of pair particles assumed that polymer reorganization around the particles is much faster than particle's diffusive time, so that the coupling of diffusive and convective effects can be neglected. Here we present a nonequilibrium two-fluid (polymer and solvent) model to resolve the convective depletion effect. The theoretical framework is based on ground state approximation and accounts for the coupling of fluid flow and polymer transport to better describe pair particle interactions. The momentum and polymer transport, chemical potential, and local viscosity and osmotic pressure are simultaneously solved by numerical approximation. This investigation is essential for predicting the demixing kinetics in the pairwise regime for colloid-polymer mixtures. This work is supported by NSF CMMI 0952646.

  3. Halocarbon ozone depletion and global warming potentials

    NASA Technical Reports Server (NTRS)

    Cox, Richard A.; Wuebbles, D.; Atkinson, R.; Connell, Peter S.; Dorn, H. P.; Derudder, A.; Derwent, Richard G.; Fehsenfeld, F. C.; Fisher, D.; Isaksen, Ivar S. A.

    1990-01-01

    Concern over the global environmental consequences of fully halogenated chlorofluorocarbons (CFCs) has created a need to determine the potential impacts of other halogenated organic compounds on stratospheric ozone and climate. The CFCs, which do not contain an H atom, are not oxidized or photolyzed in the troposphere. These compounds are transported into the stratosphere where they decompose and can lead to chlorine catalyzed ozone depletion. The hydrochlorofluorocarbons (HCFCs or HFCs), in particular those proposed as substitutes for CFCs, contain at least one hydrogen atom in the molecule, which confers on these compounds a much greater sensitivity toward oxidation by hydroxyl radicals in the troposphere, resulting in much shorter atmospheric lifetimes than CFCs, and consequently lower potential for depleting ozone. The available information is reviewed which relates to the lifetime of these compounds (HCFCs and HFCs) in the troposphere, and up-to-date assessments are reported of the potential relative effects of CFCs, HCFCs, HFCs, and halons on stratospheric ozone and global climate (through 'greenhouse' global warming).

  4. A critical comparison of ionospheric depletion chemicals

    NASA Astrophysics Data System (ADS)

    Bernhardt, P. A.

    1987-05-01

    Six chemicals, H2, H2O, CO2, SF6, CF3Br, and Ni(CO)4, are considered as ionospheric modification agents. Each of these species reacts in the F region to produce localized plasma depletions. The first three interact with O(+) and yield polyatomic ions which dissociatively recombine with electrons to give neutrals. The last three dissociatively attach electrons to produce heavy negative ions which become mutually neutralized by reactions with O(+). The effectiveness of these chemicals depends on the amount which goes into the vapor state upon release. Thermodynamic calculations show that H2O has the lowest vapor yield of about 20 percent from a heated, pressurized tank. Over 60 percent of the other substances should be vented in gaseous form. Based on estimates of plasma density reduction and airglow stimulation, nickel carbonyl is the most efficient of the six species for modifying the nighttime ionosphere. During the daytime, CF3Br and SF6 provide the largest depletions.

  5. Stratospheric ozone depletion and animal health.

    PubMed

    Mayer, S J

    1992-08-01

    There is an increasing concern over ozone depletion and its effects on the environment and human health. However, the increase in ultraviolet-B radiation (UV-B) that would result from significant losses of ozone is also potentially harmful to animals. Any increase in disease in domestic species would not only have serious animal welfare implications but may also be economically important. The diseases which are likely to increase if ozone depletion continues include the squamous cell carcinomas of the exposed, non-pigmented areas of cats, cattle, sheep and horses. Uberreiter's syndrome in dogs is also associated with exposure to UV-B and may be expected to increase, as may the severity of conditions such as infectious keratoconjunctivitis (New Forest eye) in cattle. Aquaculture systems in which fish often have little or no protection by shading may also be at risk. Cataracts and skin lesions have been associated with the exposure of farmed fish to ultraviolet radiation and have resulted in significant losses. PMID:1529513

  6. Methods used to calculate doses resulting from inhalation of Capstone depleted uranium aerosols.

    PubMed

    Miller, Guthrie; Cheng, Yung Sung; Traub, Richard J; Little, Tom T; Guilmette, Raymond A

    2009-03-01

    The methods used to calculate radiological and toxicological doses to hypothetical persons inside either a U.S. Army Abrams tank or Bradley Fighting Vehicle that has been perforated by depleted uranium munitions are described. Data from time- and particle-size-resolved measurements of depleted uranium aerosol as well as particle-size-resolved measurements of aerosol solubility in lung fluids for aerosol produced in the breathing zones of the hypothetical occupants were used. The aerosol was approximated as a mixture of nine monodisperse (single particle size) components corresponding to particle size increments measured by the eight stages plus the backup filter of the cascade impactors used. A Markov Chain Monte Carlo Bayesian analysis technique was employed, which straightforwardly calculates the uncertainties in doses. Extensive quality control checking of the various computer codes used is described. PMID:19204488

  7. Discussion on LDPC Codes and Uplink Coding

    NASA Technical Reports Server (NTRS)

    Andrews, Ken; Divsalar, Dariush; Dolinar, Sam; Moision, Bruce; Hamkins, Jon; Pollara, Fabrizio

    2007-01-01

    This slide presentation reviews the progress that the workgroup on Low-Density Parity-Check (LDPC) for space link coding. The workgroup is tasked with developing and recommending new error correcting codes for near-Earth, Lunar, and deep space applications. Included in the presentation is a summary of the technical progress of the workgroup. Charts that show the LDPC decoder sensitivity to symbol scaling errors are reviewed, as well as a chart showing the performance of several frame synchronizer algorithms compared to that of some good codes and LDPC decoder tests at ESTL. Also reviewed is a study on Coding, Modulation, and Link Protocol (CMLP), and the recommended codes. A design for the Pseudo-Randomizer with LDPC Decoder and CRC is also reviewed. A chart that summarizes the three proposed coding systems is also presented.

  8. Manually operated coded switch

    DOEpatents

    Barnette, Jon H.

    1978-01-01

    The disclosure relates to a manually operated recodable coded switch in which a code may be inserted, tried and used to actuate a lever controlling an external device. After attempting a code, the switch's code wheels must be returned to their zero positions before another try is made.

  9. Binary primitive alternant codes

    NASA Technical Reports Server (NTRS)

    Helgert, H. J.

    1975-01-01

    In this note we investigate the properties of two classes of binary primitive alternant codes that are generalizations of the primitive BCH codes. For these codes we establish certain equivalence and invariance relations and obtain values of d and d*, the minimum distances of the prime and dual codes.

  10. Algebraic geometric codes

    NASA Technical Reports Server (NTRS)

    Shahshahani, M.

    1991-01-01

    The performance characteristics are discussed of certain algebraic geometric codes. Algebraic geometric codes have good minimum distance properties. On many channels they outperform other comparable block codes; therefore, one would expect them eventually to replace some of the block codes used in communications systems. It is suggested that it is unlikely that they will become useful substitutes for the Reed-Solomon codes used by the Deep Space Network in the near future. However, they may be applicable to systems where the signal to noise ratio is sufficiently high so that block codes would be more suitable than convolutional or concatenated codes.

  11. Microfabrics in depleted mantle plaeotransform (New Caledonia)

    NASA Astrophysics Data System (ADS)

    Teyssier, Christian; Chatzaras, Vasileios; Von Der Handt, Anette

    2016-04-01

    The New Caledonia ophiolite contains several wrench zones that have been interpreted as paleotransforms. These transform-ridge systems developed at the transition between ridge development and intra-oceanic subduction that resulted in depleted mantle (about 18 % melt according to olivine Mg# - spinel Cr#). The most prominent is the Bogota Peninsula paleotransform, a 10 km wide shear zone in which strain localizes in the 2 km wide Ouassé mylonite zone. This strain gradient is associated with microstructure and microfabric evolution that informs the relationship between hydration and strain in mantle mylonite. Olivine recrystallized grain size varies from about 1 mm to about 0.2 mm toward the mylonite zone. The strain gradient is also demonstrated by increasing deformation of orthopyroxene (opx) grains that become elongate porphyroclasts in the mylonite zone. Orthopyroxene geothermometry reveals T ~ 1050-1000 C (Ca-opx) and 950-850 C (Cr-Al-opx) in the least deformed rocks. In the mylonite zone a wider range of T is recorded, with minima reaching 850 C (Ca-opx) and 750 C (Cr-Al-opx). Electron microprobe analysis also detects the presence of 20-200 micron interstitial, high-temperature amphibole (pargasite), with modal abundance increasing in the mylonite zone; this suggests that high-temperature pervasive fluid flow may have played a role in strain localization and mylonitization. Olivine crystallographic fabrics include A-type and E-type, the latter possibly reflecting hydration of shear zone tectonites. E-type fabrics are present in both mylonite and less deformed rocks, and appear to be more common in rocks with olivine grain size < 400 microns. A correlation between E-type fabrics and amphibole mode is being investigated. The shear zone protolith was depleted mantle in which the ridge-transform system was permeated by fluids. These fluids initially originated at the subduction interface, but during the transform evolution, ocean water likely permeated the shear

  12. ARA type protograph codes

    NASA Technical Reports Server (NTRS)

    Divsalar, Dariush (Inventor); Abbasfar, Aliazam (Inventor); Jones, Christopher R. (Inventor); Dolinar, Samuel J. (Inventor); Thorpe, Jeremy C. (Inventor); Andrews, Kenneth S. (Inventor); Yao, Kung (Inventor)

    2008-01-01

    An apparatus and method for encoding low-density parity check codes. Together with a repeater, an interleaver and an accumulator, the apparatus comprises a precoder, thus forming accumulate-repeat-accumulate (ARA codes). Protographs representing various types of ARA codes, including AR3A, AR4A and ARJA codes, are described. High performance is obtained when compared to the performance of current repeat-accumulate (RA) or irregular-repeat-accumulate (IRA) codes.

  13. QR Codes 101

    ERIC Educational Resources Information Center

    Crompton, Helen; LaFrance, Jason; van 't Hooft, Mark

    2012-01-01

    A QR (quick-response) code is a two-dimensional scannable code, similar in function to a traditional bar code that one might find on a product at the supermarket. The main difference between the two is that, while a traditional bar code can hold a maximum of only 20 digits, a QR code can hold up to 7,089 characters, so it can contain much more…

  14. Arctic Ozone Depletion from UARS MLS Measurements

    NASA Technical Reports Server (NTRS)

    Manney, G. L.

    1995-01-01

    Microwave Limb Sounder (MLS) measurements of ozone during four Arctic winters are compared. The evolution of ozone in the lower stratosphere is related to temperature, chlorine monoxide (also measured by MLS), and the evolution of the polar vortex. Lagrangian transport calculations using winds from the United Kingdom Meteorological Office's Stratosphere-Troposphere Data Assimilation system are used to estimate to what extent the evolution of lower stratospheric ozone is controlled by dynamics. Observations, along with calculations of the expected dynamical behavior, show evidence for chemical ozone depletion throughout most of the Arctic lower stratospheric vortex during the 1992-93 middle and late winter, and during all of the 1994-95 winter that was observed by MLS. Both of these winters were unusually cold and had unusually cold and had unusually strong Arctic polar vortices compared to meteorological data over the past 17 years.

  15. Health effects of embedded depleted uranium.

    PubMed

    McClain, David E; Benson, Kimberly A; Dalton, Tom K; Ejnik, John; Emond, Christy A; Hodge, Shelly J; Kalinich, John F; Landauer, Michael R; Livengood, David R; Miller, Alexandra C; Pellmar, Terry C; Stewart, Michael D; Villa, Vilmar; Xu, Jiaquan

    2002-02-01

    The health effects of embedded fragments of depleted uranium (DU) are being investigated to determine whether current surgical fragment-removal policies are appropriate for this metal. The authors studied rodents implanted with DU pellets as well as cultured human cells exposed to DU compounds. Results indicate that uranium from implanted DU fragments distributes to tissues distant from implantation sites, including bone, kidney, muscle, and liver. Despite levels of uranium in kidney that would be nephrotoxic after acute exposure, no histological or functional kidney toxicity was observed with embedded DU, indicating that the kidney adapts when exposed chronically. Nonetheless, further studies of the long-term health impact are needed. DU is mutagenic and transforms human osteoblastic cells into a tumorigenic phenotype. It alters neurophysiological parameters in rat hippocampus, crosses the placental barrier, and enters fetal tissue. Preliminary data also indicate decreased rodent litter size when animals are bred 6 months or longer after DU implantation. PMID:11873491

  16. Vacancy Formation Enthalpy in Polycrystalline Depleted Uranium

    NASA Astrophysics Data System (ADS)

    Lund, K. R.; Lynn, K. G.; Weber, M. H.; Okuniewski, M. A.

    2013-06-01

    Positron Annihilation Spectroscopy was performed as a function of temperature and beam energy on polycrystalline depleted uranium (DU) foil. Samples were run with varying heat profiles all starting at room temperature. While collecting Doppler-Broadening data, the temperature of the sample was cycled several times. The first heat cycle shows an increasing S-parameter near temperatures of 400K to 500K much lower than the first phase transition of 941K indicating increasing vacancies possibly due to oxygen diffusion from the bulk to the surface. Vacancy formation enthalpies were calculated fitting a model to the data to be 1.6± 0.16 eV. Results are compared to previous work [3,4].

  17. Policies on global warming and ozone depletion

    SciTech Connect

    Green, B.

    1987-04-01

    The recent discovery of a dramatic seasonal drop in the amount of ozone over Antarctica has catalyzed concern for protection of stratospheric ozone, the layer of gas that shields the entire planet from excess ultraviolet radiation. Conservative scientific models predict about a 5% reduction in the amount of global ozone by the middle of the next century, with large local variations. The predicted global warming from increased emissions of greenhouse gases will also have differing effects on local climate and weather conditions and consequently on agriculture. Although numerous uncertainties are associated with both ozone depletion and a global warming, there is a consensus that world leaders need to address the problems. The US Congress is now beginning to take note of the task. In this article, one representative outlines some perceptions of the problems and the policy options available to Congress.

  18. Tylosin depletion from edible pig tissues.

    PubMed

    Prats, C; El Korchi, G; Francesch, R; Arboix, M; Pérez, B

    2002-12-01

    The depletion of tylosin from edible pig tissues was studied following 5 days of intramuscular (i.m.) administration of 10 mg/kg of tylosin to 16 crossbreed pigs. Animals were slaughtered at intervals after treatment and samples of muscle, kidney, liver, skin+fat, and injection site were collected and analysed by high-performance liquid chromatography (HPLC). Seven days after the completion of treatment, the concentration of tylosin in kidney, skin+fat, and at the injection site was higher than the European Union maximal residue limit (MRL) of 100 microg/kg. Tylosin residues in all tissues were below the quantification limit (50 microg/kg) at 10 and 14 days post-treatment. PMID:12443694

  19. Modelling chemical depletion profiles in regolith

    USGS Publications Warehouse

    Brantley, S.L.; Bandstra, J.; Moore, J.; White, A.F.

    2008-01-01

    Chemical or mineralogical profiles in regolith display reaction fronts that document depletion of leachable elements or minerals. A generalized equation employing lumped parameters was derived to model such ubiquitously observed patterns:C = frac(C0, frac(C0 - Cx = 0, Cx = 0) exp (??ini ?? over(k, ??) ?? x) + 1)Here C, Cx = 0, and Co are the concentrations of an element at a given depth x, at the top of the reaction front, or in parent respectively. ??ini is the roughness of the dissolving mineral in the parent and k???? is a lumped kinetic parameter. This kinetic parameter is an inverse function of the porefluid advective velocity and a direct function of the dissolution rate constant times mineral surface area per unit volume regolith. This model equation fits profiles of concentration versus depth for albite in seven weathering systems and is consistent with the interpretation that the surface area (m2 mineral m- 3 bulk regolith) varies linearly with the concentration of the dissolving mineral across the front. Dissolution rate constants can be calculated from the lumped fit parameters for these profiles using observed values of weathering advance rate, the proton driving force, the geometric surface area per unit volume regolith and parent concentration of albite. These calculated values of the dissolution rate constant compare favorably to literature values. The model equation, useful for reaction fronts in both steady-state erosional and quasi-stationary non-erosional systems, incorporates the variation of reaction affinity using pH as a master variable. Use of this model equation to fit depletion fronts for soils highlights the importance of buffering of pH in the soil system. Furthermore, the equation should allow better understanding of the effects of important environmental variables on weathering rates. ?? 2008.

  20. OrigenArp Primer: How to Perform Isotopic Depletion and Decay Calculations with SCALE/ORIGEN

    SciTech Connect

    Bowman, Stephen M; Gauld, Ian C

    2010-08-01

    The SCALE (Standardized Computer Analyses for Licensing Evaluation) computer software system developed at Oak Ridge National Laboratory is widely used and accepted around the world for nuclear analyses. ORIGEN-ARP is a SCALE isotopic depletion and decay analysis sequence used to perform point-depletion calculations with the well-known ORIGEN-S code using problem-dependent cross sections. Problem-dependent cross-section libraries are generated using the ARP (Automatic Rapid Processing) module using an interpolation algorithm that operates on pre-generated libraries created for a range of fuel properties and operating conditions. Methods are provided in SCALE to generate these libraries using one-, two-, and three-dimensional transport codes. The interpolation of cross sections for uranium-based fuels may be performed for the variables burnup, enrichment, and water density. An option is also available to interpolate cross sections for mixed-oxide (MOX) fuels using the variables burnup, plutonium content, plutonium isotopic vector, and water moderator density. This primer is designed to help a new user understand and use ORIGEN-ARP with the OrigenArp Windows graphical user interface in SCALE. It assumes that the user has a college education in a technical field. There is no assumption of familiarity with nuclear depletion codes in general or with SCALE/ORIGEN-ARP in particular. The primer is based on SCALE 6 but should be applicable to earlier or later versions of SCALE. Information is included to help new users, along with several sample problems that walk the user through the different input forms and menus and illustrate the basic features. References to related documentation are provided. The primer provides a starting point for the nuclear analyst who uses SCALE/ORIGEN-ARP. Complete descriptions are provided in the SCALE documentation. Although the primer is self-contained, it is intended as a companion volume to the SCALE documentation. The SCALE Manual is

  1. Using depletion to control colloidal crystal assemblies of hard cuboctahedra.

    PubMed

    Karas, Andrew S; Glaser, Jens; Glotzer, Sharon C

    2016-06-21

    Depletion interactions arise from entropic forces, and their ability to induce aggregation and even ordering of colloidal particles through self-assembly is well established, especially for spherical colloids. We vary the size and concentration of penetrable hard sphere depletants in a system of cuboctahedra, and we show how depletion changes the preferential facet alignment of the colloids and thereby selects different crystal structures. Moreover, we explain the cuboctahedra phase behavior using perturbative free energy calculations. We find that cuboctahedra can form a stable simple cubic phase, and, remarkably, that the stability of this phase can be rationalized only by considering the effects of both the colloid and depletant entropy. We corroborate our results by analyzing how the depletant concentration and size affect the emergent directional entropic forces and hence the effective particle shape. We propose the use of depletants as a means of easily changing the effective shape of self-assembling anisotropic colloids. PMID:27194463

  2. A fast and flexible reactor physics model for simulating neutron spectra and depletion in fast reactors

    NASA Astrophysics Data System (ADS)

    Recktenwald, Geoff; Deinert, Mark

    2010-03-01

    Determining the time dependent concentration of isotopes within a nuclear reactor core is central to the analysis of nuclear fuel cycles. We present a fast, flexible tool for determining the time dependent neutron spectrum within fast reactors. The code (VBUDS: visualization, burnup, depletion and spectra) uses a two region, multigroup collision probability model to simulate the energy dependent neutron flux and tracks the buildup and burnout of 24 actinides, as well as fission products. While originally developed for LWR simulations, the model is shown to produce fast reactor spectra that show high degree of fidelity to available fast reactor benchmarks.

  3. Asymmetric quantum convolutional codes

    NASA Astrophysics Data System (ADS)

    La Guardia, Giuliano G.

    2016-01-01

    In this paper, we construct the first families of asymmetric quantum convolutional codes (AQCCs). These new AQCCs are constructed by means of the CSS-type construction applied to suitable families of classical convolutional codes, which are also constructed here. The new codes have non-catastrophic generator matrices, and they have great asymmetry. Since our constructions are performed algebraically, i.e. we develop general algebraic methods and properties to perform the constructions, it is possible to derive several families of such codes and not only codes with specific parameters. Additionally, several different types of such codes are obtained.

  4. Elemental Depletions in the Magellanic Clouds and the Evolution of Depletions with Metallicity

    NASA Astrophysics Data System (ADS)

    Tchernyshyov, Kirill; Meixner, Margaret; Seale, Jonathan; Fox, Andrew; Friedman, Scott D.; Dwek, Eli; Galliano, Frédéric

    2015-10-01

    We present a study of the composition of gas and dust in the Large and Small Magellanic Clouds (LMC and SMC) using UV absorption spectroscopy. We measure P ii and Fe ii along 84 spatially distributed sightlines toward the MCs using archival Far Ultraviolet Spectroscopic Explorer observations. For 16 of those sightlines, we also measure Si ii, Cr ii, and Zn ii from new Hubble Space Telescope Cosmic Origins Spectrograph observations. We analyze these spectra using a new spectral line analysis technique based on a semi-parametric Voigt profile model. We have combined these measurements with H i and H2 column densities and reference stellar abundances from the literature to derive gas-phase abundances, depletions, and gas-to-dust ratios (GDRs). Of our 84 P and 16 Zn measurements, 80 and 13, respectively, are depleted by more than 0.1 dex, suggesting that P and Zn abundances are not accurate metallicity indicators at and above the metallicity of the SMC. Si, Cr, and Fe are systematically less depleted in the SMC than in the Milky Way (MW) or LMC. The minimum Si depletion in the SMC is consistent with zero. We find GDR ranges of 190-565 in the LMC and 480-2100 in the SMC, which is broadly consistent with GDRs from the literature. These ranges represent actual location to location variation and are evidence of dust destruction and/or growth in the diffuse neutral phase of the interstellar medium. Where they overlap in metallicity, the gas-phase abundances of the MW, LMC, and SMC and damped Lyα systems evolve similarly with metallicity.

  5. Regret causes ego-depletion and finding benefits in the regrettable events alleviates ego-depletion.

    PubMed

    Gao, Hongmei; Zhang, Yan; Wang, Fang; Xu, Yan; Hong, Ying-Yi; Jiang, Jiang

    2014-01-01

    This study tested the hypotheses that experiencing regret would result in ego-depletion, while finding benefits (i.e., "silver linings") in the regret-eliciting events counteracted the ego-depletion effect. Using a modified gambling paradigm (Experiments 1, 2, and 4) and a retrospective method (Experiments 3 and 5), five experiments were conducted to induce regret. Results revealed that experiencing regret undermined performance on subsequent tasks, including a paper-and-pencil calculation task (Experiment 1), a Stroop task (Experiment 2), and a mental arithmetic task (Experiment 3). Furthermore, finding benefits in the regret-eliciting events improved subsequent performance (Experiments 4 and 5), and this improvement was mediated by participants' perceived vitality (Experiment 4). This study extended the depletion model of self-regulation by considering emotions with self-conscious components (in our case, regret). Moreover, it provided a comprehensive understanding of how people felt and performed after experiencing regret and after finding benefits in the events that caused the regret. PMID:24940811

  6. Cellulases and coding sequences

    DOEpatents

    Li, Xin-Liang; Ljungdahl, Lars G.; Chen, Huizhong

    2001-01-01

    The present invention provides three fungal cellulases, their coding sequences, recombinant DNA molecules comprising the cellulase coding sequences, recombinant host cells and methods for producing same. The present cellulases are from Orpinomyces PC-2.

  7. Cellulases and coding sequences

    DOEpatents

    Li, Xin-Liang; Ljungdahl, Lars G.; Chen, Huizhong

    2001-02-20

    The present invention provides three fungal cellulases, their coding sequences, recombinant DNA molecules comprising the cellulase coding sequences, recombinant host cells and methods for producing same. The present cellulases are from Orpinomyces PC-2.

  8. Multiple Turbo Codes

    NASA Technical Reports Server (NTRS)

    Divsalar, D.; Pollara, F.

    1995-01-01

    A description is given of multiple turbo codes and a suitable decoder structure derived from an approximation to the maximum a posteriori probability (MAP) decision rule, which is substantially different from the decoder for two-code-based encoders.

  9. QR Code Mania!

    ERIC Educational Resources Information Center

    Shumack, Kellie A.; Reilly, Erin; Chamberlain, Nik

    2013-01-01

    space, has error-correction capacity, and can be read from any direction. These codes are used in manufacturing, shipping, and marketing, as well as in education. QR codes can be created to produce…

  10. STEEP32 computer code

    NASA Technical Reports Server (NTRS)

    Goerke, W. S.

    1972-01-01

    A manual is presented as an aid in using the STEEP32 code. The code is the EXEC 8 version of the STEEP code (STEEP is an acronym for shock two-dimensional Eulerian elastic plastic). The major steps in a STEEP32 run are illustrated in a sample problem. There is a detailed discussion of the internal organization of the code, including a description of each subroutine.

  11. Podocyte Depletion in Thin GBM and Alport Syndrome

    PubMed Central

    Wang, Su Q.; Afshinnia, Farsad; Kershaw, David; Wiggins, Roger C.

    2016-01-01

    The proximate genetic cause of both Thin GBM and Alport Syndrome (AS) is abnormal α3, 4 and 5 collagen IV chains resulting in abnormal glomerular basement membrane (GBM) structure/function. We previously reported that podocyte detachment rate measured in urine is increased in AS, suggesting that podocyte depletion could play a role in causing progressive loss of kidney function. To test this hypothesis podometric parameters were measured in 26 kidney biopsies from 21 patients aged 2–17 years with a clinic-pathologic diagnosis including both classic Alport Syndrome with thin and thick GBM segments and lamellated lamina densa [n = 15] and Thin GBM cases [n = 6]. Protocol biopsies from deceased donor kidneys were used as age-matched controls. Podocyte depletion was present in AS biopsies prior to detectable histologic abnormalities. No abnormality was detected by light microscopy at <30% podocyte depletion, minor pathologic changes (mesangial expansion and adhesions to Bowman’s capsule) were present at 30–50% podocyte depletion, and FSGS was progressively present above 50% podocyte depletion. eGFR did not change measurably until >70% podocyte depletion. Low level proteinuria was an early event at about 25% podocyte depletion and increased in proportion to podocyte depletion. These quantitative data parallel those from model systems where podocyte depletion is the causative event. This result supports a hypothesis that in AS podocyte adherence to the GBM is defective resulting in accelerated podocyte detachment causing progressive podocyte depletion leading to FSGS-like pathologic changes and eventual End Stage Kidney Disease. Early intervention to reduce podocyte depletion is projected to prolong kidney survival in AS. PMID:27192434

  12. Syndromes associated with mitochondrial DNA depletion

    PubMed Central

    2014-01-01

    Mitochondrial dysfunction accounts for a large group of inherited metabolic disorders most of which are due to a dysfunctional mitochondrial respiratory chain (MRC) and, consequently, deficient energy production. MRC function depends on the coordinated expression of both nuclear (nDNA) and mitochondrial (mtDNA) genomes. Thus, mitochondrial diseases can be caused by genetic defects in either the mitochondrial or the nuclear genome, or in the cross-talk between the two. This impaired cross-talk gives rise to so-called nuclear-mitochondrial intergenomic communication disorders, which result in loss or instability of the mitochondrial genome and, in turn, impaired maintenance of qualitative and quantitative mtDNA integrity. In children, most MRC disorders are associated with nuclear gene defects rather than alterations in the mtDNA itself. The mitochondrial DNA depletion syndromes (MDSs) are a clinically heterogeneous group of disorders with an autosomal recessive pattern of transmission that have onset in infancy or early childhood and are characterized by a reduced number of copies of mtDNA in affected tissues and organs. The MDSs can be divided into least four clinical presentations: hepatocerebral, myopathic, encephalomyopathic and neurogastrointestinal. The focus of this review is to offer an overview of these syndromes, listing the clinical phenotypes, together with their relative frequency, mutational spectrum, and possible insights for improving diagnostic strategies. PMID:24708634

  13. Recovery of Depleted Uranium Fragments from Soil

    SciTech Connect

    Farr, C.P.; Alecksen, T.J.; Heronimus, R.S.; Simonds, M.H.; Farrar, D.R.; Baker, K.R.; Miller, M.L.

    2008-07-01

    A cost-effective method was demonstrated for recovering depleted uranium (DU) fragments from soil. A compacted clean soil pad was prepared adjacent to a pile of soil containing DU fragments. Soil from the contaminated pile was placed on the pad in three-inch lifts using conventional construction equipment. Each lift was scanned with an automatic scanning system consisting of an array of radiation detectors coupled to a detector positioning system. The data were downloaded into ArcGIS for data presentation. Areas of the pad exhibiting scaler counts above the decision level were identified as likely locations of DU fragments. The coordinates of these locations were downloaded into a PDA that was wirelessly connected to the positioning system. The PDA guided technicians to the locations where hand-held trowels and shovels were used to remove the fragments. After DU removal, the affected areas were re-scanned and the new data patched into the data base to replace the original data. This new data set along with soil sample results served as final status survey data. (authors)

  14. Ozone depletion: 20 Years after the alarm

    SciTech Connect

    Not Available

    1994-08-15

    Scientific curiosity in 1973 led to the challenge of determining the ultimate atmospheric fate of the chlorofluoromethanes, CFC-11 (CCl[sub 3]F) and CFC-12 (CCl[sub 2]F[sub 2]), whose presence at measurable levels in surface air had been detected only two years earlier. In retrospect, the decision to pursue the chemistry of CFC molecules to their final destruction and beyond foreordained an unusual outcome because CFCs are chemically inert and easily survive under almost all natural conditions. By midsummer 1994, the world is well on its way in transition to a CFC-free economy, although not yet to a CFC-free atmosphere. The rates of increase in atmospheric concentration for the three major CFCs (CFC-11, -12, and -113) have all slowed markedly in response to the restrictions of the revised Montreal protocol. Because of their long lifetimes, however, significant but gradually diminishing quantities of CFCs will remain in the atmosphere throughout the 21st century. Atomic chlorine will continue to be released into the stratosphere as long as CFCs persist, and ozone depletion will follow. The existence of the Montreal protocol and the agreement among industrial, governmental, and university scientists on its wisdom offers considerable promise for the handling of future global environmental problems.

  15. Research on mitigation of stratospheric ozone depletion

    SciTech Connect

    Wong, A.Y. )

    1994-08-01

    Chlorine atoms released from CFCs by solar Ultraviolet (UV) radiation and from natural sources, are effective catalytic agents for the destruction of stratospheric ozone. Research into large-scale mitigation methods is based on charging the chlorine radical, converting it into negative ions of low reactivity. Generation of charges-and subsequent removal of chlorine ions by atmospheric platforms and electromagnetic waves are described. This method is generally applicable to all halogens. This research is guided by the principle that the solution should be as non-intrusive environmentally as possible; i.e. no chemicals are to be injected. The large-scale mitigation requires the process to be energy efficient and to utilize energy sources already present in the atmosphere. Because of the wide variety of remediation concepts, each is being tested using a combination of laboratory and field experiments together with computer modeling. The first laboratory demonstration of ozone depletion and subsequent recovery due to charge injection is presented. [copyright][ital American] [ital Institute] [ital of] [ital Physics

  16. Tylosin depletion in edible tissues of turkeys.

    PubMed

    Montesissa, C; De Liguoro, M; Santi, A; Capolongo, F; Biancotto, G

    1999-10-01

    The depletion of tylosin residues in edible turkey tissues was followed after 3 days of administration of tylosin tartrate at 500 mg l-1 in drinking water, to 30 turkeys. Immediately after the end of the treatment (day 0) and at day 1, 3, 5 and 10 of withdrawal, six turkeys (three males and three females) per time were sacrificed and samples of edible tissues were collected. Tissue homogenates were extracted, purified and analysed by HPLC according to a method previously published for the analysis of tylosin residues in pig tissues. In all tissues, tylosin residues were already below the detection limits of 50 micrograms kg-1 at time zero. However, in several samples of tissues (skin + fat, liver, kidney, muscle), from the six turkeys sacrificed at that time, one peak corresponding to an unknown tylosin equivalent was detected at measurable concentrations. The identification of this unknown compound was performed by LC-MS/MS analysis of the extracts from incurred samples. The mass fragmentation of the compound was consistent with the structure of tylosin D (the alcoholic derivative of tylosin A), the major metabolite of tylosin previously recovered and identified in tissues and/or excreta from treated chickens, cattle and pigs. PMID:10755131

  17. Color code identification in coded structured light.

    PubMed

    Zhang, Xu; Li, Youfu; Zhu, Limin

    2012-08-01

    Color code is widely employed in coded structured light to reconstruct the three-dimensional shape of objects. Before determining the correspondence, a very important step is to identify the color code. Until now, the lack of an effective evaluation standard has hindered the progress in this unsupervised classification. In this paper, we propose a framework based on the benchmark to explore the new frontier. Two basic facets of the color code identification are discussed, including color feature selection and clustering algorithm design. First, we adopt analysis methods to evaluate the performance of different color features, and the order of these color features in the discriminating power is concluded after a large number of experiments. Second, in order to overcome the drawback of K-means, a decision-directed method is introduced to find the initial centroids. Quantitative comparisons affirm that our method is robust with high accuracy, and it can find or closely approach the global peak. PMID:22859022

  18. Adipogenesis and aldosterone: a study in lean tryptophan-depleted rats.

    PubMed

    Pokusa, Michal; Hlavacova, Natasa; Csanova, Agnesa; Franklin, Michael; Zorad, Stefan; Jezova, Daniela

    2016-07-01

    Next to epithelial tissues, mineralocorticoid receptors are also expressed in adipose tissue and are involved in the process of adipogenesis. Mineralocorticoid receptors in adipose tissue are likely to be activated mainly by glucocorticoids. The aim of the present study was to test the hypothesis that the processes related to adipogenesis are modified under the conditions associated with high circulating aldosterone. We have made advantage of a model of depression based on tryptophan depletion in which we have previously demonstrated that the elevation of serum aldosterone precedes that of corticosterone. Sixty adult female Sprague-Dawley rats were fed either a low tryptophan diet or control diet for 4 (elevation of aldosterone only), 7 and 14 days (broader neuroendocrine activation) respectively. Gene expression of several adipogenic factors, CD31, interleukin-6, adiponectin, resistin and leptin were evaluated. Levels of mRNAs coding for adipogenic, angiogenic and inflammatory factors in adipose tissue were elevated at 4 and 7 days of tryptophan depletion. Additionally, gene expression of aldosterone sensing 11-β-hydroxysteroid dehydrogenase 2 and mineralocorticoid receptors were elevated. All changes disappeared at 14 days of tryptophan depletion. Synchronously an increase of adipose tissue mass was observed. Although direct evidence is not provided, observed changes in gene expression may be related to the action of aldosterone on mineralocorticoid receptors. Our findings represent the first data on any changes in gene expression in adipose tissue in animal models of depression. PMID:27253873

  19. Software Certification - Coding, Code, and Coders

    NASA Technical Reports Server (NTRS)

    Havelund, Klaus; Holzmann, Gerard J.

    2011-01-01

    We describe a certification approach for software development that has been adopted at our organization. JPL develops robotic spacecraft for the exploration of the solar system. The flight software that controls these spacecraft is considered to be mission critical. We argue that the goal of a software certification process cannot be the development of "perfect" software, i.e., software that can be formally proven to be correct under all imaginable and unimaginable circumstances. More realistically, the goal is to guarantee a software development process that is conducted by knowledgeable engineers, who follow generally accepted procedures to control known risks, while meeting agreed upon standards of workmanship. We target three specific issues that must be addressed in such a certification procedure: the coding process, the code that is developed, and the skills of the coders. The coding process is driven by standards (e.g., a coding standard) and tools. The code is mechanically checked against the standard with the help of state-of-the-art static source code analyzers. The coders, finally, are certified in on-site training courses that include formal exams.

  20. LINKAGE BETWEEN CLIMATE CHANGE AND STRATOSPHERIC OZONE DEPLETION

    EPA Science Inventory

    Two primary areas link the issue of stratospheric ozone depletion to global climate change: atmospheric processes and ecological processes. tmospheric processes establish a linkage through the dual roles of certain trace gases in promoting global warming and in depleting the ozon...

  1. Influence of Roller Burnishing Parameters on Depletion of Plasticity Reserve

    NASA Astrophysics Data System (ADS)

    Blumenstein, V. Yu; Petrenko, K. P.

    2016-04-01

    Roller burnishing process considerably increases surface quality and service life of machine parts. Efficiency of roller burnishing rises greatly when technological inheritance (TI) is taken into account. Research results of degree of plasticity reserve depletion (DPRD) while roller burnishing are presented. Results obtained made it possible to establish mechanisms of strain accumulation and plasticity reserve depletion according to roller burnishing parameters.

  2. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 7 2010-04-01 2010-04-01 true Percentage depletion; general rule. 1.613-1 Section 1.613-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion;...

  3. 26 CFR 1.613-1 - Percentage depletion; general rule.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Percentage depletion; general rule. 1.613-1 Section 1.613-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.613-1 Percentage depletion; general rule. (a) In general. In the case of a...

  4. Auto-aligning stimulated emission depletion microscope using adaptive optics

    PubMed Central

    Gould, Travis J.; Kromann, Emil B.; Burke, Daniel; Booth, Martin J.; Bewersdorf, Joerg

    2013-01-01

    Stimulated emission depletion (STED) microscopy provides diffraction-unlimited resolution in fluorescence microscopy. Imaging at the nanoscale, however, requires precise alignment of the depletion and excitation laser foci of the STED microscope. We demonstrate here that adaptive optics can be implemented to automatically align STED and confocal images with a precision of 4.3 ± 2.3 nm. PMID:23722769

  5. Optimal Allocation of Sampling Effort in Depletion Surveys

    EPA Science Inventory

    We consider the problem of designing a depletion or removal survey as part of estimating animal abundance for populations with imperfect capture or detection rates. In a depletion survey, animals are captured from a given area, counted, and withheld from the population. This proc...

  6. BENZENE VAPOR DEPLETION IN THE PRESENCE OF PLANTS

    EPA Science Inventory

    Three plant species, Eichhornia crassipes in a nutrient hydroponic culture Beta vulgaris saccharifera, and Beta vulgaris cicla in soil and in water cultures, were found to deplete benzene from the air. Following benzene depletion, plant tissues were extracted and no benzene was d...

  7. XSOR codes users manual

    SciTech Connect

    Jow, Hong-Nian; Murfin, W.B.; Johnson, J.D.

    1993-11-01

    This report describes the source term estimation codes, XSORs. The codes are written for three pressurized water reactors (Surry, Sequoyah, and Zion) and two boiling water reactors (Peach Bottom and Grand Gulf). The ensemble of codes has been named ``XSOR``. The purpose of XSOR codes is to estimate the source terms which would be released to the atmosphere in severe accidents. A source term includes the release fractions of several radionuclide groups, the timing and duration of releases, the rates of energy release, and the elevation of releases. The codes have been developed by Sandia National Laboratories for the US Nuclear Regulatory Commission (NRC) in support of the NUREG-1150 program. The XSOR codes are fast running parametric codes and are used as surrogates for detailed mechanistic codes. The XSOR codes also provide the capability to explore the phenomena and their uncertainty which are not currently modeled by the mechanistic codes. The uncertainty distributions of input parameters may be used by an. XSOR code to estimate the uncertainty of source terms.

  8. DLLExternalCode

    SciTech Connect

    Greg Flach, Frank Smith

    2014-05-14

    DLLExternalCode is the a general dynamic-link library (DLL) interface for linking GoldSim (www.goldsim.com) with external codes. The overall concept is to use GoldSim as top level modeling software with interfaces to external codes for specific calculations. The DLLExternalCode DLL that performs the linking function is designed to take a list of code inputs from GoldSim, create an input file for the external application, run the external code, and return a list of outputs, read from files created by the external application, back to GoldSim. Instructions for creating the input file, running the external code, and reading the output are contained in an instructions file that is read and interpreted by the DLL.

  9. DLLExternalCode

    Energy Science and Technology Software Center (ESTSC)

    2014-05-14

    DLLExternalCode is the a general dynamic-link library (DLL) interface for linking GoldSim (www.goldsim.com) with external codes. The overall concept is to use GoldSim as top level modeling software with interfaces to external codes for specific calculations. The DLLExternalCode DLL that performs the linking function is designed to take a list of code inputs from GoldSim, create an input file for the external application, run the external code, and return a list of outputs, read frommore » files created by the external application, back to GoldSim. Instructions for creating the input file, running the external code, and reading the output are contained in an instructions file that is read and interpreted by the DLL.« less

  10. Barium depletion study on impregnated cathodes and lifetime prediction

    NASA Astrophysics Data System (ADS)

    Roquais, J. M.; Poret, F.; le Doze, R.; Ricaud, J. L.; Monterrin, A.; Steinbrunn, A.

    2003-06-01

    In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK).

  11. Ozone depletion during solar proton events in solar cycle 21

    NASA Technical Reports Server (NTRS)

    Mcpeters, R. D.; Jackman, C. H.

    1985-01-01

    Ozone profile data from the Solar Backscattered Ultraviolet Instrument on Nimbus 7 from 1979 to the present and clear cases of ozone destruction associated with five sudden proton events (SPEs) on June 7, 1979, August 21, 1979, October 13-14, 1981, July 13, 1982, and December 8, 1982 are found. During the SPE on July 13, 1982, the largest of this solar cycle, no depletion at all at 45 km is observed, but there is a 15 percent ozone depletion at 50 km increasing to 27 percent at 55 km, all at a solar zenith angle of 85 deg. A strong variation of the observed depletion with solar zenith angle is found, with maximum depletion occurring at the largest zenith angles (near 85 deg) decreasing to near zero for angles below about 70 deg. The observed depletion is short lived, disappearing within hours of the end of the SPE.

  12. Charged micelle depletion attraction and interfacial colloidal phase behavior.

    PubMed

    Iracki, Tara D; Beltran-Villegas, Daniel J; Eichmann, Shannon L; Bevan, Michael A

    2010-12-21

    Ensemble total internal reflection microscopy (TIRM) is used to directly measure the evolution of colloid-surface depletion attraction with increasing sodium dodecyl sulfate (SDS) concentration near the critical micelle concentration (CMC). Measured potentials are well described by a modified Asakura-Oosawa (AO) depletion potential in addition to electrostatic and van der Waals contributions. The modified AO potential includes effects of electrostatic interactions between micelles and surfaces via effective depletant dimensions in an excluded volume term and partitioning in an osmotic pressure term. Directly measured colloid-surface depletion potentials are used in Monte Carlo (MC) simulations to capture video microscopy (VM) measurements of micelle-mediated quasi-two-dimensional phase behavior including fluid, crystal, and gel microstructures. Our findings provide information to develop more rigorous and analytically simple models of depletion attraction in charged micellar systems. PMID:21077612

  13. Ionogram range/time plots, satellite traces and optical depletions

    NASA Astrophysics Data System (ADS)

    Lynn, Kenneth; Shiokawa, Kazuo; Otsuka, Yuichi; Wilkinson, Phil

    2012-07-01

    Range/time plots derived from 5 minute ionograms have a variety of uses including finding TIDs, following major height variations in the F2 ionosphere and tracking the movement of low latitude electron depletions as verified by co-incident observations by optical methods. This paper investigates these applications with particular emphasis on following optical depletions via ionosonde as observed at Darwin, Australia. Similar additional range/time plots are also discussed from Vanimo and Port Moresby in New Guinea and Tennant Creek and Townsville in Australia. While much theoretical work has been expended on explaining the development of equatorial bubble/depletions, current work highlights the apparently strong development of depletions at times of year when the pre-sunset height rise and following fall is minimal in contrast to current conventional thinking. In contrast, depletions are not observed at Australian equatorial longitudes when the pre- and post- sunset height variations are greatest in magnitude and consistency.

  14. The timing and mechanism of depletion in Lewisian granulites

    NASA Technical Reports Server (NTRS)

    Cohen, A. S.; Onions, R. K.; Ohara, M. J.

    1988-01-01

    Large Ion Lithophile (LIL) depletion in Lewisian granulites is discussed. Severe depletions in U, Th, and other LIL have been well documented in Lewisan mafic and felsic gneisses, but new Pb isotopic analyses show little or no depletion in lithologies with high solidus temperatures, such as peridotite. This suggests that LIL transport in this terrane took place by removal of partial melts rather than by pervasive flooding with externally derived CO2. The Pb and Nd isotopic data gathered on these rocks show that the depletion and granulite metamorphism are distinct events about 250 Ma apart. Both fluid inclusions and cation exchange geothermometers date from the later metamorphic event and therefore have little bearing on the depletion event, suggesting a note of caution for interpretations of other granulite terranes.

  15. Ozone Depletion Potential of CH3Br

    NASA Technical Reports Server (NTRS)

    Sander, Stanley P.; Ko, Malcolm K. W.; Sze, Nien Dak; Scott, Courtney; Rodriquez, Jose M.; Weisenstein, Debra K.

    1998-01-01

    The ozone depletion potential (ODP) of methyl bromide (CH3Br) can be determined by combining the model-calculated bromine efficiency factor (BEF) for CH3Br and its atmospheric lifetime. This paper examines how changes in several key kinetic data affect BEF. The key reactions highlighted in this study include the reaction of BrO + H02, the absorption cross section of HOBr, the absorption cross section and the photolysis products of BrON02, and the heterogeneous conversion of BrON02 to HOBR and HN03 on aerosol particles. By combining the calculated BEF with the latest estimate of 0.7 year for the atmospheric lifetime of CH3Br, the likely value of ODP for CH3Br is 0.39. The model-calculated concentration of HBr (approximately 0.3 pptv) in the lower stratosphere is substantially smaller than the reported measured value of about I pptv. Recent publications suggested models can reproduce the measured value if one assumes a yield for HBr from the reaction of BrO + OH or from the reaction of BrO + H02. Although the DeAlore et al. evaluation concluded any substantial yield of HBr from BrO + HO2 is unlikely, for completeness, we calculate the effects of these assumed yields on BEF for CH3Br. Our calculations show that the effects are minimal: practically no impact for an assumed 1.3% yield of HBr from BrO + OH and 10% smaller for an assumed 0.6% yield from BrO + H02.

  16. Barium Depletion in Hollow Cathode Emitters

    NASA Technical Reports Server (NTRS)

    Polk, James E.; Capece, Angela M.; Mikellides, Ioannis G.; Katz, Ira

    2009-01-01

    The effect of tungsten erosion, transport and redeposition on the operation of dispenser hollow cathodes was investigated in detailed examinations of the discharge cathode inserts from an 8200 hour and a 30,352 hour ion engine wear test. Erosion and subsequent re-deposition of tungsten in the electron emission zone at the downstream end of the insert reduces the porosity of the tungsten matrix, preventing the ow of barium from the interior. This inhibits the interfacial reactions of the barium-calcium-aluminate impregnant with the tungsten in the pores. A numerical model of barium transport in the internal xenon discharge plasma shows that the barium required to reduce the work function in the emission zone can be supplied from upstream through the gas phase. Barium that flows out of the pores of the tungsten insert is rapidly ionized in the xenon discharge and pushed back to the emitter surface by the electric field and drag from the xenon ion flow. This barium ion flux is sufficient to maintain a barium surface coverage at the downstream end greater than 0.6, even if local barium production at that point is inhibited by tungsten deposits. The model also shows that the neutral barium pressure exceeds the equilibrium vapor pressure of the impregnant decomposition reaction over much of the insert length, so the reactions are suppressed. Only a small region upstream of the zone blocked by tungsten deposits is active and supplies the required barium. These results indicate that hollow cathode failure models based on barium depletion rates in vacuum dispenser cathodes are very conservative.

  17. Estimates of radiological risk from depleted uranium weapons in war scenarios.

    PubMed

    Durante, Marco; Pugliese, Mariagabriella

    2002-01-01

    Several weapons used during the recent conflict in Yugoslavia contain depleted uranium, including missiles and armor-piercing incendiary rounds. Health concern is related to the use of these weapons, because of the heavy-metal toxicity and radioactivity of uranium. Although chemical toxicity is considered the more important source of health risk related to uranium, radiation exposure has been allegedly related to cancers among veterans of the Balkan conflict, and uranium munitions are a possible source of contamination in the environment. Actual measurements of radioactive contamination are needed to assess the risk. In this paper, a computer simulation is proposed to estimate radiological risk related to different exposure scenarios. Dose caused by inhalation of radioactive aerosols and ground contamination induced by Tomahawk missile impact are simulated using a Gaussian plume model (HOTSPOT code). Environmental contamination and committed dose to the population resident in contaminated areas are predicted by a food-web model (RESRAD code). Small values of committed effective dose equivalent appear to be associated with missile impacts (50-y CEDE < 5 mSv), or population exposure by water-independent pathways (50-y CEDE < 80 mSv). The greatest hazard is related to the water contamination in conditions of effective leaching of uranium in the groundwater (50-y CEDE < 400 mSv). Even in this worst case scenario, the chemical toxicity largely predominates over radiological risk. These computer simulations suggest that little radiological risk is associated to the use of depleted uranium weapons. PMID:11768794

  18. RNase J depletion leads to massive changes in mRNA abundance in Helicobacter pylori.

    PubMed

    Redko, Yulia; Galtier, Eloïse; Arnion, Hélène; Darfeuille, Fabien; Sismeiro, Odile; Coppée, Jean-Yves; Médigue, Claudine; Weiman, Marion; Cruveiller, Stéphane; De Reuse, Hilde

    2016-02-01

    Degradation of RNA as an intermediate message between genes and corresponding proteins is important for rapid attenuation of gene expression and maintenance of cellular homeostasis. This process is controlled by ribonucleases that have different target specificities. In the bacterial pathogen Helicobacter pylori, an exo- and endoribonuclease RNase J is essential for growth. To explore the role of RNase J in H. pylori, we identified its putative targets at a global scale using next generation RNA sequencing. We found that strong depletion for RNase J led to a massive increase in the steady-state levels of non-rRNAs. mRNAs and RNAs antisense to open reading frames were most affected with over 80% increased more than 2-fold. Non-coding RNAs expressed in the intergenic regions were much less affected by RNase J depletion. Northern blotting of selected messenger and non-coding RNAs validated these results. Globally, our data suggest that RNase J of H. pylori is a major RNase involved in degradation of most cellular RNAs. PMID:26726773

  19. Adjoint-based uncertainty quantification and sensitivity analysis for reactor depletion calculations

    NASA Astrophysics Data System (ADS)

    Stripling, Hayes Franklin

    Depletion calculations for nuclear reactors model the dynamic coupling between the material composition and neutron flux and help predict reactor performance and safety characteristics. In order to be trusted as reliable predictive tools and inputs to licensing and operational decisions, the simulations must include an accurate and holistic quantification of errors and uncertainties in its outputs. Uncertainty quantification is a formidable challenge in large, realistic reactor models because of the large number of unknowns and myriad sources of uncertainty and error. We present a framework for performing efficient uncertainty quantification in depletion problems using an adjoint approach, with emphasis on high-fidelity calculations using advanced massively parallel computing architectures. This approach calls for a solution to two systems of equations: (a) the forward, engineering system that models the reactor, and (b) the adjoint system, which is mathematically related to but different from the forward system. We use the solutions of these systems to produce sensitivity and error estimates at a cost that does not grow rapidly with the number of uncertain inputs. We present the framework in a general fashion and apply it to both the source-driven and k-eigenvalue forms of the depletion equations. We describe the implementation and verification of solvers for the forward and ad- joint equations in the PDT code, and we test the algorithms on realistic reactor analysis problems. We demonstrate a new approach for reducing the memory and I/O demands on the host machine, which can be overwhelming for typical adjoint algorithms. Our conclusion is that adjoint depletion calculations using full transport solutions are not only computationally tractable, they are the most attractive option for performing uncertainty quantification on high-fidelity reactor analysis problems.

  20. Adaptive entropy coded subband coding of images.

    PubMed

    Kim, Y H; Modestino, J W

    1992-01-01

    The authors describe a design approach, called 2-D entropy-constrained subband coding (ECSBC), based upon recently developed 2-D entropy-constrained vector quantization (ECVQ) schemes. The output indexes of the embedded quantizers are further compressed by use of noiseless entropy coding schemes, such as Huffman or arithmetic codes, resulting in variable-rate outputs. Depending upon the specific configurations of the ECVQ and the ECPVQ over the subbands, many different types of SBC schemes can be derived within the generic 2-D ECSBC framework. Among these, the authors concentrate on three representative types of 2-D ECSBC schemes and provide relative performance evaluations. They also describe an adaptive buffer instrumented version of 2-D ECSBC, called 2-D ECSBC/AEC, for use with fixed-rate channels which completely eliminates buffer overflow/underflow problems. This adaptive scheme achieves performance quite close to the corresponding ideal 2-D ECSBC system. PMID:18296138

  1. Observations of TEC Depletions in South and Central America

    NASA Astrophysics Data System (ADS)

    Valladares, C. E.; Sheehan, R. E.; Pradipta, R.

    2014-12-01

    TEC values gathered with several networks of GPS receivers, which operated in South and Central America and the Caribbean region between 2010 and 2013, have been used to investigate the characteristics and morphology of TEC depletions that develop at these locations. In South America the TEC depletions are associated with low-latitude plasma bubbles. In Central America and the Caribbean region, we found that TEC depletions that occur during magnetically active conditions (Kp > 5o), persist for very long periods and sometimes remain even during afternoon hours. During quiet magnetic conditions, TEC depletions occur around the June solstice in Central America and during the December solstice in the Southern part of South America. We have also studied possible links between mid-latitude depletions and the formation of plasma bubbles at low latitudes. In addition, TEC measurements from North America have been utilized to determine the poleward extension of the mid-latitude depletions. These depletions do not appear to be related to auroral plasma processes or to storm enhanced densities (SED). We are studying the possibility that their initiation process is associated with the disturbance dynamo or the prompt penetrating electric field that develop during storm conditions.

  2. Protein disulfide isomerase mediates glutathione depletion-induced cytotoxicity.

    PubMed

    Okada, Kazushi; Fukui, Masayuki; Zhu, Bao-Ting

    2016-08-26

    Glutathione depletion is a distinct cause underlying many forms of pathogenesis associated with oxidative stress and cytotoxicity. Earlier studies showed that glutamate-induced glutathione depletion in immortalized murine HT22 hippocampal neuronal cells leads to accumulation of reactive oxygen species (ROS) and ultimately cell death, but the precise mechanism underlying these processes is not clear. Here we show that during the induction of glutathione depletion, nitric oxide (NO) accumulation precedes ROS accumulation. While neuronal NO synthase (nNOS) in untreated HT22 cells exists mostly as a monomer, glutathione depletion results in increased formation of the dimer nNOS, accompanied by increases in the catalytic activity. We identified that nNOS dimerization is catalyzed by protein disulfide isomerase (PDI). Inhibition of PDI's isomerase activity effectively abrogates glutathione depletion-induced conversion of monomer nNOS into dimer nNOS, accumulation of NO and ROS, and cytotoxicity. Furthermore, we found that PDI is present in untreated cells in an inactive S-nitrosylated form, which becomes activated following glutathione depletion via S-denitrosylation. These results reveal a novel role for PDI in mediating glutathione depletion-induced oxidative cytotoxicity, as well as its role as a valuable therapeutic target for protection against oxidative cytotoxicity. PMID:27317486

  3. Adjoint simulation of stream depletion due to aquifer pumping.

    PubMed

    Neupauer, Roseanna M; Griebling, Scott A

    2012-01-01

    If an aquifer is hydraulically connected to an adjacent stream, a pumping well operating in the aquifer will draw some water from aquifer storage and some water from the stream, causing stream depletion. Several analytical, semi-analytical, and numerical approaches have been developed to estimate stream depletion due to pumping. These approaches are effective if the well location is known. If a new well is to be installed, it may be desirable to install the well at a location where stream depletion is minimal. If several possible locations are considered for the location of a new well, stream depletion would have to be estimated for all possible well locations, which can be computationally inefficient. The adjoint approach for estimating stream depletion is a more efficient alternative because with one simulation of the adjoint model, stream depletion can be estimated for pumping at a well at any location. We derive the adjoint equations for a coupled system with a confined aquifer, an overlying unconfined aquifer, and a river that is hydraulically connected to the unconfined aquifer. We assume that the stage in the river is known, and is independent of the stream depletion, consistent with the assumptions of the MODFLOW river package. We describe how the adjoint equations can be solved using MODFLOW. In an illustrative example, we show that for this scenario, the adjoint approach is as accurate as standard forward numerical simulation methods, and requires substantially less computational effort. PMID:22182421

  4. CO depletion in ATLASGAL-selected high-mass clumps

    NASA Astrophysics Data System (ADS)

    Giannetti, A.; Wyrowski, F.; Brand, J.; Csengeri, T.; Fontani, F.; Walmsley, C. M.; Nguyen Luong, Q.; Beuther, H.; Schuller, F.; Güsten, R.; Menten, K. M.

    2016-05-01

    In the low-mass regime, it is found that the gas-phase abundances of C-bearing molecules in cold starless cores rapidly decrease with increasing density. Here the molecules tend to stick to the grains, forming ice mantles. We study CO depletion in the TOP100 sample of the ATLASGAL survey, and investigate its correlation with evolutionary stage and with the physical parameters of the sources. We use low-J emission lines of CO isotopologues and the dust continuum emission to infer the depletion factor fD. RATRAN one-dimensional models were also used to determine fD and to investigate the presence of depletion above a density threshold. The isotopic ratios and optical depth were derived with a Bayesian approach. We find a significant number of clumps with a large CO depletion, up to ˜20. Larger values are found for colder clumps, thus for earlier evolutionary phases. For massive clumps in the earliest stages of evolution we estimate the radius of the region where CO depletion is important to be a few tenths of a pc. CO depletion in high-mass clumps seems to behave as in the low-mass regime, with less evolved clumps showing larger values for the depletion than their more evolved counterparts, and increasing for denser sources.

  5. Long-term groundwater depletion in the United States.

    PubMed

    Konikow, Leonard F

    2015-01-01

    The volume of groundwater stored in the subsurface in the United States decreased by almost 1000 km3 during 1900-2008. The aquifer systems with the three largest volumes of storage depletion include the High Plains aquifer, the Mississippi Embayment section of the Gulf Coastal Plain aquifer system, and the Central Valley of California. Depletion rates accelerated during 1945-1960, averaging 13.6 km3/year during the last half of the century, and after 2000 increased again to about 24 km3/year. Depletion intensity is a new parameter, introduced here, to provide a more consistent basis for comparing storage depletion problems among various aquifers by factoring in time and areal extent of the aquifer. During 2001-2008, the Central Valley of California had the largest depletion intensity. Groundwater depletion in the United States can explain 1.4% of observed sea-level rise during the 108-year study period and 2.1% during 2001-2008. Groundwater depletion must be confronted on local and regional scales to help reduce demand (primarily in irrigated agriculture) and/or increase supply. PMID:25510437

  6. Masting in whitebark pine (Pinus albicaulis) depletes stored nutrients.

    PubMed

    Sala, Anna; Hopping, Kelly; McIntire, Eliot J B; Delzon, Sylvain; Crone, Elizabeth E

    2012-10-01

    • In masting trees, synchronized, heavy reproductive events are thought to deplete stored resources and to impose a replenishment period before subsequent masting. However, direct evidence of resource depletion in wild, masting trees is very rare. Here, we examined the timing and magnitude (local vs individual-level) of stored nutrient depletion after a heavy mast event in Pinus albicaulis. • In 2005, the mast year, we compared seasonal changes in leaf and sapwood nitrogen (N) and phosphorus (P) concentrations and leaf photosynthetic rates in cone-bearing branches, branches that never produced cones, and branches with experimentally removed cones. We also compared nutrient concentrations in cone branches and branches that had never had cones between 2005 and 2006, and measured tree ring width and new shoot growth during 2005. • During the mast year, N or P depletion occurred only in tissue fractions of reproductive branches, where photosynthetic rates were reduced. However, by the end of the following year, nutrients were depleted in all branches, indicating individual-level resource depletion. New shoot and radial growth were not affected by masting. • We provide direct evidence that mast events in wild trees deplete stored nutrients. Our results highlight the importance of evaluating reproductive costs over time and at the individual level. PMID:22889129

  7. Generating code adapted for interlinking legacy scalar code and extended vector code

    DOEpatents

    Gschwind, Michael K

    2013-06-04

    Mechanisms for intermixing code are provided. Source code is received for compilation using an extended Application Binary Interface (ABI) that extends a legacy ABI and uses a different register configuration than the legacy ABI. First compiled code is generated based on the source code, the first compiled code comprising code for accommodating the difference in register configurations used by the extended ABI and the legacy ABI. The first compiled code and second compiled code are intermixed to generate intermixed code, the second compiled code being compiled code that uses the legacy ABI. The intermixed code comprises at least one call instruction that is one of a call from the first compiled code to the second compiled code or a call from the second compiled code to the first compiled code. The code for accommodating the difference in register configurations is associated with the at least one call instruction.

  8. Mechanical code comparator

    DOEpatents

    Peter, Frank J.; Dalton, Larry J.; Plummer, David W.

    2002-01-01

    A new class of mechanical code comparators is described which have broad potential for application in safety, surety, and security applications. These devices can be implemented as micro-scale electromechanical systems that isolate a secure or otherwise controlled device until an access code is entered. This access code is converted into a series of mechanical inputs to the mechanical code comparator, which compares the access code to a pre-input combination, entered previously into the mechanical code comparator by an operator at the system security control point. These devices provide extremely high levels of robust security. Being totally mechanical in operation, an access control system properly based on such devices cannot be circumvented by software attack alone.

  9. Theory of epigenetic coding.

    PubMed

    Elder, D

    1984-06-01

    The logic of genetic control of development may be based on a binary epigenetic code. This paper revises the author's previous scheme dealing with the numerology of annelid metamerism in these terms. Certain features of the code had been deduced to be combinatorial, others not. This paradoxical contrast is resolved here by the interpretation that these features relate to different operations of the code; the combinatiorial to coding identity of units, the non-combinatorial to coding production of units. Consideration of a second paradox in the theory of epigenetic coding leads to a new solution which further provides a basis for epimorphic regeneration, and may in particular throw light on the "regeneration-duplication" phenomenon. A possible test of the model is also put forward. PMID:6748695

  10. Updating the Read Codes

    PubMed Central

    Robinson, David; Comp, Dip; Schulz, Erich; Brown, Philip; Price, Colin

    1997-01-01

    Abstract The Read Codes are a hierarchically-arranged controlled clinical vocabulary introduced in the early 1980s and now consisting of three maintained versions of differing complexity. The code sets are dynamic, and are updated quarterly in response to requests from users including clinicians in both primary and secondary care, software suppliers, and advice from a network of specialist healthcare professionals. The codes' continual evolution of content, both across and within versions, highlights tensions between different users and uses of coded clinical data. Internal processes, external interactions and new structural features implemented by the NHS Centre for Coding and Classification (NHSCCC) for user interactive maintenance of the Read Codes are described, and over 2000 items of user feedback episodes received over a 15-month period are analysed. PMID:9391934

  11. A Multilab Preregistered Replication of the Ego-Depletion Effect.

    PubMed

    Hagger, Martin S; Chatzisarantis, Nikos L D

    2016-07-01

    Good self-control has been linked to adaptive outcomes such as better health, cohesive personal relationships, success in the workplace and at school, and less susceptibility to crime and addictions. In contrast, self-control failure is linked to maladaptive outcomes. Understanding the mechanisms by which self-control predicts behavior may assist in promoting better regulation and outcomes. A popular approach to understanding self-control is the strength or resource depletion model. Self-control is conceptualized as a limited resource that becomes depleted after a period of exertion resulting in self-control failure. The model has typically been tested using a sequential-task experimental paradigm, in which people completing an initial self-control task have reduced self-control capacity and poorer performance on a subsequent task, a state known as ego depletion Although a meta-analysis of ego-depletion experiments found a medium-sized effect, subsequent meta-analyses have questioned the size and existence of the effect and identified instances of possible bias. The analyses served as a catalyst for the current Registered Replication Report of the ego-depletion effect. Multiple laboratories (k = 23, total N = 2,141) conducted replications of a standardized ego-depletion protocol based on a sequential-task paradigm by Sripada et al. Meta-analysis of the studies revealed that the size of the ego-depletion effect was small with 95% confidence intervals (CIs) that encompassed zero (d = 0.04, 95% CI [-0.07, 0.15]. We discuss implications of the findings for the ego-depletion effect and the resource depletion model of self-control. PMID:27474142

  12. Doubled Color Codes

    NASA Astrophysics Data System (ADS)

    Bravyi, Sergey

    Combining protection from noise and computational universality is one of the biggest challenges in the fault-tolerant quantum computing. Topological stabilizer codes such as the 2D surface code can tolerate a high level of noise but implementing logical gates, especially non-Clifford ones, requires a prohibitively large overhead due to the need of state distillation. In this talk I will describe a new family of 2D quantum error correcting codes that enable a transversal implementation of all logical gates required for the universal quantum computing. Transversal logical gates (TLG) are encoded operations that can be realized by applying some single-qubit rotation to each physical qubit. TLG are highly desirable since they introduce no overhead and do not spread errors. It has been known before that a quantum code can have only a finite number of TLGs which rules out computational universality. Our scheme circumvents this no-go result by combining TLGs of two different quantum codes using the gauge-fixing method pioneered by Paetznick and Reichardt. The first code, closely related to the 2D color code, enables a transversal implementation of all single-qubit Clifford gates such as the Hadamard gate and the π / 2 phase shift. The second code that we call a doubled color code provides a transversal T-gate, where T is the π / 4 phase shift. The Clifford+T gate set is known to be computationally universal. The two codes can be laid out on the honeycomb lattice with two qubits per site such that the code conversion requires parity measurements for six-qubit Pauli operators supported on faces of the lattice. I will also describe numerical simulations of logical Clifford+T circuits encoded by the distance-3 doubled color code. Based on a joint work with Andrew Cross.

  13. Phonological coding during reading

    PubMed Central

    Leinenger, Mallorie

    2014-01-01

    The exact role that phonological coding (the recoding of written, orthographic information into a sound based code) plays during silent reading has been extensively studied for more than a century. Despite the large body of research surrounding the topic, varying theories as to the time course and function of this recoding still exist. The present review synthesizes this body of research, addressing the topics of time course and function in tandem. The varying theories surrounding the function of phonological coding (e.g., that phonological codes aid lexical access, that phonological codes aid comprehension and bolster short-term memory, or that phonological codes are largely epiphenomenal in skilled readers) are first outlined, and the time courses that each maps onto (e.g., that phonological codes come online early (pre-lexical) or that phonological codes come online late (post-lexical)) are discussed. Next the research relevant to each of these proposed functions is reviewed, discussing the varying methodologies that have been used to investigate phonological coding (e.g., response time methods, reading while eyetracking or recording EEG and MEG, concurrent articulation) and highlighting the advantages and limitations of each with respect to the study of phonological coding. In response to the view that phonological coding is largely epiphenomenal in skilled readers, research on the use of phonological codes in prelingually, profoundly deaf readers is reviewed. Finally, implications for current models of word identification (activation-verification model (Van Order, 1987), dual-route model (e.g., Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001), parallel distributed processing model (Seidenberg & McClelland, 1989)) are discussed. PMID:25150679

  14. Phonological coding during reading.

    PubMed

    Leinenger, Mallorie

    2014-11-01

    The exact role that phonological coding (the recoding of written, orthographic information into a sound based code) plays during silent reading has been extensively studied for more than a century. Despite the large body of research surrounding the topic, varying theories as to the time course and function of this recoding still exist. The present review synthesizes this body of research, addressing the topics of time course and function in tandem. The varying theories surrounding the function of phonological coding (e.g., that phonological codes aid lexical access, that phonological codes aid comprehension and bolster short-term memory, or that phonological codes are largely epiphenomenal in skilled readers) are first outlined, and the time courses that each maps onto (e.g., that phonological codes come online early [prelexical] or that phonological codes come online late [postlexical]) are discussed. Next the research relevant to each of these proposed functions is reviewed, discussing the varying methodologies that have been used to investigate phonological coding (e.g., response time methods, reading while eye-tracking or recording EEG and MEG, concurrent articulation) and highlighting the advantages and limitations of each with respect to the study of phonological coding. In response to the view that phonological coding is largely epiphenomenal in skilled readers, research on the use of phonological codes in prelingually, profoundly deaf readers is reviewed. Finally, implications for current models of word identification (activation-verification model, Van Orden, 1987; dual-route model, e.g., M. Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001; parallel distributed processing model, Seidenberg & McClelland, 1989) are discussed. PMID:25150679

  15. Bar Code Labels

    NASA Technical Reports Server (NTRS)

    1988-01-01

    American Bar Codes, Inc. developed special bar code labels for inventory control of space shuttle parts and other space system components. ABC labels are made in a company-developed anodizing aluminum process and consecutively marketed with bar code symbology and human readable numbers. They offer extreme abrasion resistance and indefinite resistance to ultraviolet radiation, capable of withstanding 700 degree temperatures without deterioration and up to 1400 degrees with special designs. They offer high resistance to salt spray, cleaning fluids and mild acids. ABC is now producing these bar code labels commercially or industrial customers who also need labels to resist harsh environments.

  16. MORSE Monte Carlo code

    SciTech Connect

    Cramer, S.N.

    1984-01-01

    The MORSE code is a large general-use multigroup Monte Carlo code system. Although no claims can be made regarding its superiority in either theoretical details or Monte Carlo techniques, MORSE has been, since its inception at ORNL in the late 1960s, the most widely used Monte Carlo radiation transport code. The principal reason for this popularity is that MORSE is relatively easy to use, independent of any installation or distribution center, and it can be easily customized to fit almost any specific need. Features of the MORSE code are described.

  17. Tokamak Systems Code

    SciTech Connect

    Reid, R.L.; Barrett, R.J.; Brown, T.G.; Gorker, G.E.; Hooper, R.J.; Kalsi, S.S.; Metzler, D.H.; Peng, Y.K.M.; Roth, K.E.; Spampinato, P.T.

    1985-03-01

    The FEDC Tokamak Systems Code calculates tokamak performance, cost, and configuration as a function of plasma engineering parameters. This version of the code models experimental tokamaks. It does not currently consider tokamak configurations that generate electrical power or incorporate breeding blankets. The code has a modular (or subroutine) structure to allow independent modeling for each major tokamak component or system. A primary benefit of modularization is that a component module may be updated without disturbing the remainder of the systems code as long as the imput to or output from the module remains unchanged.

  18. FAA Smoke Transport Code

    SciTech Connect

    Domino, Stefan; Luketa-Hanlin, Anay; Gallegos, Carlos

    2006-10-27

    FAA Smoke Transport Code, a physics-based Computational Fluid Dynamics tool, which couples heat, mass, and momentum transfer, has been developed to provide information on smoke transport in cargo compartments with various geometries and flight conditions. The software package contains a graphical user interface for specification of geometry and boundary conditions, analysis module for solving the governing equations, and a post-processing tool. The current code was produced by making substantial improvements and additions to a code obtained from a university. The original code was able to compute steady, uniform, isothermal turbulent pressurization. In addition, a preprocessor and postprocessor were added to arrive at the current software package.

  19. Expander chunked codes

    NASA Astrophysics Data System (ADS)

    Tang, Bin; Yang, Shenghao; Ye, Baoliu; Yin, Yitong; Lu, Sanglu

    2015-12-01

    Chunked codes are efficient random linear network coding (RLNC) schemes with low computational cost, where the input packets are encoded into small chunks (i.e., subsets of the coded packets). During the network transmission, RLNC is performed within each chunk. In this paper, we first introduce a simple transfer matrix model to characterize the transmission of chunks and derive some basic properties of the model to facilitate the performance analysis. We then focus on the design of overlapped chunked codes, a class of chunked codes whose chunks are non-disjoint subsets of input packets, which are of special interest since they can be encoded with negligible computational cost and in a causal fashion. We propose expander chunked (EC) codes, the first class of overlapped chunked codes that have an analyzable performance, where the construction of the chunks makes use of regular graphs. Numerical and simulation results show that in some practical settings, EC codes can achieve rates within 91 to 97 % of the optimum and outperform the state-of-the-art overlapped chunked codes significantly.

  20. Bipolar optical pulse coding for performance enhancement in BOTDA sensors.

    PubMed

    Soto, Marcelo A; Le Floch, Sébastien; Thévenaz, Luc

    2013-07-15

    A pump signal based on bipolar pulse coding and single-sideband suppressed-carried (SSB-SC) modulation is proposed for Brillouin optical time-domain analysis (BOTDA) sensors. Making a sequential use of the Brillouin gain and loss spectra, the technique is experimentally validated using bipolar complementary-correlation Golay codes along a 100 km-long fiber and 2 m spatial resolution, fully resolving a 2 m hot-spot at the end of the sensing fiber with no distortion introduced by the decoding algorithm. Experimental results, in good agreement with the theory, indicate that bipolar Golay codes provide a higher signal-to-noise ratio enhancement and stronger robustness to pump depletion in comparison to optimum unipolar pulse codes known for BOTDA sensing. PMID:23938490

  1. The 'depletion layer' of amorphous p-n junctions

    NASA Technical Reports Server (NTRS)

    Von Roos, O.

    1981-01-01

    It is shown that within reasonable approximations for the density of state distribution within the mobility gap of a:Si, a one-to-one correspondence exists between the electric field distribution in the transition region of an amorphous p-n junction and that in the depletion layer of a crystalline p-n junction. Thus it is inferred that the depletion layer approximation which leads to a parabolic potential distribution within the depletion layer of crystalline junctions also constitutes a fair approximation in the case of amorphous junctions. This fact greatly simplifies an analysis of solid-state electronic devices based on amorphous material (i.e., solar cells).

  2. Challenges dealing with depleted uranium in Germany - Reuse or disposal

    SciTech Connect

    Moeller, Kai D.

    2007-07-01

    During enrichment large amounts of depleted Uranium are produced. In Germany every year 2.800 tons of depleted uranium are generated. In Germany depleted uranium is not classified as radioactive waste but a resource for further enrichment. Therefore since 1996 depleted Uranium is sent to ROSATOM in Russia. However it still has to be dealt with the second generation of depleted Uranium. To evaluate the alternative actions in case a solution has to be found in Germany, several studies have been initiated by the Federal Ministry of the Environment. The work that has been carried out evaluated various possibilities to deal with depleted uranium. The international studies on this field and the situation in Germany have been analyzed. In case no further enrichment is planned the depleted uranium has to be stored. In the enrichment process UF{sub 6} is generated. It is an international consensus that for storage it should be converted to U{sub 3}O{sub 8}. The necessary technique is well established. If the depleted Uranium would have to be characterized as radioactive waste, a final disposal would become necessary. For the planned Konrad repository - a repository for non heat generating radioactive waste - the amount of Uranium is limited by the licensing authority. The existing license would not allow the final disposal of large amounts of depleted Uranium in the Konrad repository. The potential effect on the safety case has not been roughly analyzed. As a result it may be necessary to think about alternatives. Several possibilities for the use of depleted uranium in the industry have been identified. Studies indicate that the properties of Uranium would make it useful in some industrial fields. Nevertheless many practical and legal questions are open. One further option may be the use as shielding e.g. in casks for transport or disposal. Possible techniques for using depleted Uranium as shielding are the use of the metallic Uranium as well as the inclusion in concrete

  3. Lithium depletion and the star age connection

    NASA Astrophysics Data System (ADS)

    Carlos, Marília Gabriela C. C.

    2015-12-01

    It is known that lithium is destroyed in the inner layers of a star via proton capture ( 7Li(p, α)α) at temperatures near to 2.5 ∗ 106 K. Due to the fact that Li burning happens when the element is transported to the innermost and hotter regions through convective motions of the star, Li abundance studies offers an excellent opportunity to understand the extent of the mixing processes within and below the stellar convective zone. Thus, for a better understanding of the inner stars regions, this study aims to observe correlations between lithium abundances, stellar age, masses and planets occurrence for various solar twins aged between 0.7 and 8.8 Gyr.The sample consists of 21 solar twins measured in the HARPS spectrograph with spectral resolution R≈115.000 and signal to noise ratio from 400 to 2400. The lithium abundance were obtained by spectral synthesis of the line 6707.75 Å with the aid of MOOG code.The results indicate a strong correlation between age and Li abundances in the stars of this sample and a non-connection between lithium abundances and the presence of planets.

  4. Research on Universal Combinatorial Coding

    PubMed Central

    Lu, Jun; Zhang, Zhuo; Mo, Juan

    2014-01-01

    The conception of universal combinatorial coding is proposed. Relations exist more or less in many coding methods. It means that a kind of universal coding method is objectively existent. It can be a bridge connecting many coding methods. Universal combinatorial coding is lossless and it is based on the combinatorics theory. The combinational and exhaustive property make it closely related with the existing code methods. Universal combinatorial coding does not depend on the probability statistic characteristic of information source, and it has the characteristics across three coding branches. It has analyzed the relationship between the universal combinatorial coding and the variety of coding method and has researched many applications technologies of this coding method. In addition, the efficiency of universal combinatorial coding is analyzed theoretically. The multicharacteristic and multiapplication of universal combinatorial coding are unique in the existing coding methods. Universal combinatorial coding has theoretical research and practical application value. PMID:24772019

  5. Research on universal combinatorial coding.

    PubMed

    Lu, Jun; Zhang, Zhuo; Mo, Juan

    2014-01-01

    The conception of universal combinatorial coding is proposed. Relations exist more or less in many coding methods. It means that a kind of universal coding method is objectively existent. It can be a bridge connecting many coding methods. Universal combinatorial coding is lossless and it is based on the combinatorics theory. The combinational and exhaustive property make it closely related with the existing code methods. Universal combinatorial coding does not depend on the probability statistic characteristic of information source, and it has the characteristics across three coding branches. It has analyzed the relationship between the universal combinatorial coding and the variety of coding method and has researched many applications technologies of this coding method. In addition, the efficiency of universal combinatorial coding is analyzed theoretically. The multicharacteristic and multiapplication of universal combinatorial coding are unique in the existing coding methods. Universal combinatorial coding has theoretical research and practical application value. PMID:24772019

  6. Fast Coding Unit Encoding Mechanism for Low Complexity Video Coding

    PubMed Central

    Wu, Yueying; Jia, Kebin; Gao, Guandong

    2016-01-01

    In high efficiency video coding (HEVC), coding tree contributes to excellent compression performance. However, coding tree brings extremely high computational complexity. Innovative works for improving coding tree to further reduce encoding time are stated in this paper. A novel low complexity coding tree mechanism is proposed for HEVC fast coding unit (CU) encoding. Firstly, this paper makes an in-depth study of the relationship among CU distribution, quantization parameter (QP) and content change (CC). Secondly, a CU coding tree probability model is proposed for modeling and predicting CU distribution. Eventually, a CU coding tree probability update is proposed, aiming to address probabilistic model distortion problems caused by CC. Experimental results show that the proposed low complexity CU coding tree mechanism significantly reduces encoding time by 27% for lossy coding and 42% for visually lossless coding and lossless coding. The proposed low complexity CU coding tree mechanism devotes to improving coding performance under various application conditions. PMID:26999741

  7. Stimulated Emission Depletion Lithography with Mercapto-Functional Polymers

    PubMed Central

    2016-01-01

    Surface reactive nanostructures were fabricated using stimulated emission depletion (STED) lithography. The functionalization of the nanostructures was realized by copolymerization of a bifunctional metal oxo cluster in the presence of a triacrylate monomer. Ligands of the cluster surface cross-link to the monomer during the lithographic process, whereas unreacted mercapto functionalized ligands are transferred to the polymer and remain reactive after polymer formation of the surface of the nanostructure. The depletion efficiency in dependence of the cluster loading was investigated and full depletion of the STED effect was observed with a cluster loading exceeding 4 wt %. A feature size by λ/11 was achieved by using a donut-shaped depletion beam. The reactivity of the mercapto groups on the surface of the nanostructure was tested by incubation with mercapto-reactive fluorophores. PMID:26816204

  8. In situ observations of bifurcation of equatorial ionospheric plasma depletions

    SciTech Connect

    Aggson, T.L.; Pfaff, R.F.; Maynard, N.C.

    1996-03-01

    Vector electric field measurements from the San Marco D satellite are utilized to investigate the bifurcation of ionospheric plasma depletions (sometimes called {open_quotes}bubbles{close_quotes}) associated with nightside equatorial spread F. These depletions are identified by enhanced upward ExB convection in depleted plasma density channels in the nighttime equatorial ionosphere. The in situ determination of the bifurcation process is based on dc electric field measurements of the bipolar variation in the zonal flow, westward and eastward, as the eastbound satellite crosses isolated signatures of updrafting plasma depletion regions. The authors also present data in which more complicated regions of zonal velocity variations appear as the possible result of multiple bifurcations of updrafting equatorial plasma bubbles. 10 refs., 7 fig.

  9. Stimulated Emission Depletion Lithography with Mercapto-Functional Polymers.

    PubMed

    Buchegger, Bianca; Kreutzer, Johannes; Plochberger, Birgit; Wollhofen, Richard; Sivun, Dmitry; Jacak, Jaroslaw; Schütz, Gerhard J; Schubert, Ulrich; Klar, Thomas A

    2016-02-23

    Surface reactive nanostructures were fabricated using stimulated emission depletion (STED) lithography. The functionalization of the nanostructures was realized by copolymerization of a bifunctional metal oxo cluster in the presence of a triacrylate monomer. Ligands of the cluster surface cross-link to the monomer during the lithographic process, whereas unreacted mercapto functionalized ligands are transferred to the polymer and remain reactive after polymer formation of the surface of the nanostructure. The depletion efficiency in dependence of the cluster loading was investigated and full depletion of the STED effect was observed with a cluster loading exceeding 4 wt %. A feature size by λ/11 was achieved by using a donut-shaped depletion beam. The reactivity of the mercapto groups on the surface of the nanostructure was tested by incubation with mercapto-reactive fluorophores. PMID:26816204

  10. STRATOSPHERIC OZONE DEPLETION: A FOCUS ON EPA'S RESEARCH

    EPA Science Inventory

    In September of 1987 the United States, along with 26 other countries, signed a landmark treaty to limit and subsequently, through revisions, phase out the production of all significant ozone depleting substances. Many researchers suspected that these chemicals, especially chl...

  11. Optical depletion spectroscopy for probing evaporatively cooled OH

    NASA Astrophysics Data System (ADS)

    Hummon, Matthew; Wu, Hao; Stuhl, Benjamin; Reens, David; Yeo, Mark; Ye, Jun

    2013-05-01

    Pulsed laser induced fluorescence (PLIF) measurements provide a sensitive probe for the detection of molecular species. However, the broad linewidth of the pulsed lasers used for molecular excitation obscures spectral information useful for determination of molecule temperature. This limitation can be overcome by the use of a second, narrowband source of radiation that can deplete a subset of the molecules detected using PLIF, and a high resolution depletion spectrum can be obtained. In the past, we have demonstrated the use of microwave depletion spectroscopy to measure magnetically trapped, evaporatively cooled OH temperatures in the range of 5-50 mK. The lower limit of 5 mK is set by the details of the microwave transition. Here we present temperature measurements of trapped OH using an optical depletion technique, which is in principle capable of probing temperatures as low as 50 microkelvin. We acknowledge funding from the NSF Physics Frontier Center, NIST, DOE, and the AFOSR MURI on Cold Molecules.

  12. Accelerated reabsorption in the proximal tubule produced by volume depletion

    PubMed Central

    Weiner, Michael W.; Weinman, Edward J.; Kashgarian, Michael; Hayslett, John P.

    1971-01-01

    The renal response to chronic depletion of extracellular volume was examined using the techniques of micropuncture. Depletion of salt and water was produced by administration of furosemide to rats maintained on a sodium-free diet. There was a marked fall in body weight, plasma volume, and glomerular filtration rate. The intrinsic reabsorptive capacity of the proximal tubule, measured by the split-droplet technique, was greatly enhanced. The acceleration of proximal fluid reabsorption could not be accounted for by changes in filtration rate, tubular geometry, or aldosterone secretion. The half-time of droplet reabsorption in the distal tubule was not altered by sodium depletion. An increase in the reabsorption of fluid in the proximal tubule, as demonstrated directly in the present experiments, provides an explanation for a variety of clinical phenomena associated with volume depletion. Images PMID:5090054

  13. Hyperspectral stimulated emission depletion microscopy and methods of use thereof

    SciTech Connect

    Timlin, Jerilyn A; Aaron, Jesse S

    2014-04-01

    A hyperspectral stimulated emission depletion ("STED") microscope system for high-resolution imaging of samples labeled with multiple fluorophores (e.g., two to ten fluorophores). The hyperspectral STED microscope includes a light source, optical systems configured for generating an excitation light beam and a depletion light beam, optical systems configured for focusing the excitation and depletion light beams on a sample, and systems for collecting and processing data generated by interaction of the excitation and depletion light beams with the sample. Hyperspectral STED data may be analyzed using multivariate curve resolution analysis techniques to deconvolute emission from the multiple fluorophores. The hyperspectral STED microscope described herein can be used for multi-color, subdiffraction imaging of samples (e.g., materials and biological materials) and for analyzing a tissue by Forster Resonance Energy Transfer ("FRET").

  14. 10. VIEW OF DEPLETED URANIUM INGOT AND MOLD IN FOUNDRY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW OF DEPLETED URANIUM INGOT AND MOLD IN FOUNDRY. (11/11/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  15. Fluorescence depletion properties of insulin–gold nanoclusters

    PubMed Central

    Chen, Po-Fu; Liu, Chien-Liang; Lin, Wei-Kuan; Chen, Kuan-Chieh; Chou, Pi-Tai; Chu, Shi-Wei

    2015-01-01

    Insulin–gold nanoclusters exhibit outstanding biocompatibility, photostability, and fluorescence quantum efficiency. However, they have never been used in superresolution microscopy, which requires nonlinear switching or saturation of fluorescence. Here we examine the fluorescence and stimulated emission depletion properties of gold nanoclusters. Their bleaching rate is very slow, demonstrating superior photostability. Surprisingly, however, the best depletion efficiency is less than 70%, whereas the depletion intensity requirement is much higher than the expectation from a simple two-level model. Fluorescence lifetime measurement revealed two distinct lifetime components, which indicate intersystem and reverse intersystem crossing during excitation. Based on population dynamic calculation, excellent agreement of the maximal depletion efficiency is found. Our work not only features the first examination of STED with metallic clusters, but also reveals the significance of molecular transition dynamics when considering a STED labeling. PMID:26309767

  16. Synthesizing Certified Code

    NASA Technical Reports Server (NTRS)

    Whalen, Michael; Schumann, Johann; Fischer, Bernd

    2002-01-01

    Code certification is a lightweight approach to demonstrate software quality on a formal level. Its basic idea is to require producers to provide formal proofs that their code satisfies certain quality properties. These proofs serve as certificates which can be checked independently. Since code certification uses the same underlying technology as program verification, it also requires many detailed annotations (e.g., loop invariants) to make the proofs possible. However, manually adding theses annotations to the code is time-consuming and error-prone. We address this problem by combining code certification with automatic program synthesis. We propose an approach to generate simultaneously, from a high-level specification, code and all annotations required to certify generated code. Here, we describe a certification extension of AUTOBAYES, a synthesis tool which automatically generates complex data analysis programs from compact specifications. AUTOBAYES contains sufficient high-level domain knowledge to generate detailed annotations. This allows us to use a general-purpose verification condition generator to produce a set of proof obligations in first-order logic. The obligations are then discharged using the automated theorem E-SETHEO. We demonstrate our approach by certifying operator safety for a generated iterative data classification program without manual annotation of the code.

  17. Lichenase and coding sequences

    DOEpatents

    Li, Xin-Liang; Ljungdahl, Lars G.; Chen, Huizhong

    2000-08-15

    The present invention provides a fungal lichenase, i.e., an endo-1,3-1,4-.beta.-D-glucanohydrolase, its coding sequence, recombinant DNA molecules comprising the lichenase coding sequences, recombinant host cells and methods for producing same. The present lichenase is from Orpinomyces PC-2.

  18. Codes of Conduct

    ERIC Educational Resources Information Center

    Million, June

    2004-01-01

    Most schools have a code of conduct, pledge, or behavioral standards, set by the district or school board with the school community. In this article, the author features some schools that created a new vision of instilling code of conducts to students based on work quality, respect, safety and courtesy. She suggests that communicating the code…

  19. Code of Ethics

    ERIC Educational Resources Information Center

    Division for Early Childhood, Council for Exceptional Children, 2009

    2009-01-01

    The Code of Ethics of the Division for Early Childhood (DEC) of the Council for Exceptional Children is a public statement of principles and practice guidelines supported by the mission of DEC. The foundation of this Code is based on sound ethical reasoning related to professional practice with young children with disabilities and their families…

  20. Legacy Code Modernization

    NASA Technical Reports Server (NTRS)

    Hribar, Michelle R.; Frumkin, Michael; Jin, Haoqiang; Waheed, Abdul; Yan, Jerry; Saini, Subhash (Technical Monitor)

    1998-01-01

    Over the past decade, high performance computing has evolved rapidly; systems based on commodity microprocessors have been introduced in quick succession from at least seven vendors/families. Porting codes to every new architecture is a difficult problem; in particular, here at NASA, there are many large CFD applications that are very costly to port to new machines by hand. The LCM ("Legacy Code Modernization") Project is the development of an integrated parallelization environment (IPE) which performs the automated mapping of legacy CFD (Fortran) applications to state-of-the-art high performance computers. While most projects to port codes focus on the parallelization of the code, we consider porting to be an iterative process consisting of several steps: 1) code cleanup, 2) serial optimization,3) parallelization, 4) performance monitoring and visualization, 5) intelligent tools for automated tuning using performance prediction and 6) machine specific optimization. The approach for building this parallelization environment is to build the components for each of the steps simultaneously and then integrate them together. The demonstration will exhibit our latest research in building this environment: 1. Parallelizing tools and compiler evaluation. 2. Code cleanup and serial optimization using automated scripts 3. Development of a code generator for performance prediction 4. Automated partitioning 5. Automated insertion of directives. These demonstrations will exhibit the effectiveness of an automated approach for all the steps involved with porting and tuning a legacy code application for a new architecture.

  1. Modified JPEG Huffman coding.

    PubMed

    Lakhani, Gopal

    2003-01-01

    It is a well observed characteristic that when a DCT block is traversed in the zigzag order, the AC coefficients generally decrease in size and the run-length of zero coefficients increase in number. This article presents a minor modification to the Huffman coding of the JPEG baseline compression algorithm to exploit this redundancy. For this purpose, DCT blocks are divided into bands so that each band can be coded using a separate code table. Three implementations are presented, which all move the end-of-block marker up in the middle of DCT block and use it to indicate the band boundaries. Experimental results are presented to compare reduction in the code size obtained by our methods with the JPEG sequential-mode Huffman coding and arithmetic coding methods. The average code reduction to the total image code size of one of our methods is 4%. Our methods can also be used for progressive image transmission and hence, experimental results are also given to compare them with two-, three-, and four-band implementations of the JPEG spectral selection method. PMID:18237897

  2. Binary concatenated coding system

    NASA Technical Reports Server (NTRS)

    Monford, L. G., Jr.

    1973-01-01

    Coding, using 3-bit binary words, is applicable to any measurement having integer scale up to 100. System using 6-bit data words can be expanded to read from 1 to 10,000, and 9-bit data words can increase range to 1,000,000. Code may be ''read'' directly by observation after memorizing simple listing of 9's and 10's.

  3. Computerized mega code recording.

    PubMed

    Burt, T W; Bock, H C

    1988-04-01

    A system has been developed to facilitate recording of advanced cardiac life support mega code testing scenarios. By scanning a paper "keyboard" using a bar code wand attached to a portable microcomputer, the person assigned to record the scenario can easily generate an accurate, complete, timed, and typewritten record of the given situations and the obtained responses. PMID:3354937

  4. Coding for optical channels

    NASA Technical Reports Server (NTRS)

    Baumert, L. D.; Mceliece, R. J.; Rumsey, H., Jr.

    1979-01-01

    In a previous paper Pierce considered the problem of optical communication from a novel viewpoint, and concluded that performance will likely be limited by issues of coding complexity rather than by thermal noise. This paper reviews the model proposed by Pierce and presents some results on the analysis and design of codes for this application.

  5. Depleted uranium human health risk assessment, Jefferson Proving Ground, Indiana

    SciTech Connect

    Ebinger, M.H.; Hansen, W.R.

    1994-04-29

    The risk to human health from fragments of depleted uranium (DU) at Jefferson Proving Ground (JPG) was estimated using two types of ecosystem pathway models. A steady-state, model of the JPG area was developed to examine the effects of DU in soils, water, and vegetation on deer that were hunted and consumed by humans. The RESRAD code was also used to estimate the effects of farming the impact area and consuming the products derived from the farm. The steady-state model showed that minimal doses to humans are expected from consumption of deer that inhabit the impact area. Median values for doses to humans range from about 1 mrem ({plus_minus}2.4) to 0.04 mrem ({plus_minus}0.13) and translate to less than 1 {times} 10{sup {minus}6} detriments (excess cancers) in the population. Monte Carlo simulation of the steady-state model was used to derive the probability distributions from which the median values were drawn. Sensitivity analyses of the steady-state model showed that the amount of DU in airborne dust and, therefore, the amount of DU on the vegetation surface, controlled the amount of DU ingested by deer and by humans. Human doses from the RESRAD estimates ranged from less than 1 mrem/y to about 6.5 mrem/y in a hunting scenario and subsistence fanning scenario, respectively. The human doses exceeded the 100 mrem/y dose limit when drinking water for the farming scenario was obtained from the on-site aquifer that was presumably contaminated with DU. The two farming scenarios were unrealistic land uses because the additional risk to humans due to unexploded ordnance in the impact area was not figured into the risk estimate. The doses estimated with RESRAD translated to less than 1 {times} 10{sup {minus}6} detriments to about 1 {times} 10{sup {minus}3} detriments. The higher risks were associated only with the farming scenario in which drinking water was obtained on-site.

  6. Lithium Depletion in the Beta Pictoris Moving Group

    NASA Astrophysics Data System (ADS)

    Yee, Jennifer C.; Jensen, E. L.; Reaser, B. E.

    2006-12-01

    We present a study of lithium depletion in twelve late-type pre-main-sequence stars in the coeval Beta Pictoris Moving Group (BPMG). The age of this group ( 12 Myr) is well constrained because all of the stars in the sample have Hipparcos distances. We have determined Li abundances for these K and M stars using equivalent width measurements of the 6707.8 Angstrom Li I line from new high-resolution, high-S/N echelle spectra, and we compare these abundances to models of pre-main-sequence Li depletion by Baraffe et al. (1998), D'Antona & Mazzitelli (1997, 1998), and Siess, Dufour, & Forestini (2000). Significantly more lithium depletion is observed in the sample than is predicted for a group of this age. In particular, the discrepancy between the predicted and the observed lithium abundances increases with decreasing effective temperature, suggesting a problem with theories describing pre-main-sequence lithium depletion. Our data indicate that M stars deplete lithium more rapidly than predicted, which could make M-type post-T-Tauri stars difficult to identify. In addition, we compare our results to the work of Song, Bessell, & Zuckerman (2002) on HIP 112312. In contrast to that work, we did not observe the lithium depletion boundary of the BPMG; none of the three M4.5 stars in the sample showed evidence of lithium (log N(Li) < -0.5), indicating a lithium depletion boundary later than M4.5, further underscoring the gap between age estimates from lithium depletion and those from theoretical evolutionary tracks. We gratefully acknowledge the support of the National Science Foundation through grant AST-0307830.

  7. Retrieval of buried depleted uranium from the T-1 trench

    SciTech Connect

    Burmeister, M.; Castaneda, N.; Greengard, T. |; Hull, C.; Barbour, D.; Quapp, W.J.

    1998-07-01

    The Trench 1 remediation project will be conducted this year to retrieve depleted uranium and other associated materials from a trench at Rocky Flats Environmental Technology Site. The excavated materials will be segregated and stabilized for shipment. The depleted uranium will be treated at an offsite facility which utilizes a novel approach for waste minimization and disposal through utilization of a combination of uranium recycling and volume efficient uranium stabilization.

  8. Combustion chamber analysis code

    NASA Technical Reports Server (NTRS)

    Przekwas, A. J.; Lai, Y. G.; Krishnan, A.; Avva, R. K.; Giridharan, M. G.

    1993-01-01

    A three-dimensional, time dependent, Favre averaged, finite volume Navier-Stokes code has been developed to model compressible and incompressible flows (with and without chemical reactions) in liquid rocket engines. The code has a non-staggered formulation with generalized body-fitted-coordinates (BFC) capability. Higher order differencing methodologies such as MUSCL and Osher-Chakravarthy schemes are available. Turbulent flows can be modeled using any of the five turbulent models present in the code. A two-phase, two-liquid, Lagrangian spray model has been incorporated into the code. Chemical equilibrium and finite rate reaction models are available to model chemically reacting flows. The discrete ordinate method is used to model effects of thermal radiation. The code has been validated extensively against benchmark experimental data and has been applied to model flows in several propulsion system components of the SSME and the STME.

  9. Energy Conservation Code Decoded

    SciTech Connect

    Cole, Pam C.; Taylor, Zachary T.

    2006-09-01

    Designing an energy-efficient, affordable, and comfortable home is a lot easier thanks to a slime, easier to read booklet, the 2006 International Energy Conservation Code (IECC), published in March 2006. States, counties, and cities have begun reviewing the new code as a potential upgrade to their existing codes. Maintained under the public consensus process of the International Code Council, the IECC is designed to do just what its title says: promote the design and construction of energy-efficient homes and commercial buildings. Homes in this case means traditional single-family homes, duplexes, condominiums, and apartment buildings having three or fewer stories. The U.S. Department of Energy, which played a key role in proposing the changes that resulted in the new code, is offering a free training course that covers the residential provisions of the 2006 IECC.

  10. Astrophysics Source Code Library

    NASA Astrophysics Data System (ADS)

    Allen, A.; DuPrie, K.; Berriman, B.; Hanisch, R. J.; Mink, J.; Teuben, P. J.

    2013-10-01

    The Astrophysics Source Code Library (ASCL), founded in 1999, is a free on-line registry for source codes of interest to astronomers and astrophysicists. The library is housed on the discussion forum for Astronomy Picture of the Day (APOD) and can be accessed at http://ascl.net. The ASCL has a comprehensive listing that covers a significant number of the astrophysics source codes used to generate results published in or submitted to refereed journals and continues to grow. The ASCL currently has entries for over 500 codes; its records are citable and are indexed by ADS. The editors of the ASCL and members of its Advisory Committee were on hand at a demonstration table in the ADASS poster room to present the ASCL, accept code submissions, show how the ASCL is starting to be used by the astrophysics community, and take questions on and suggestions for improving the resource.

  11. Glutathione depletion impairs transcriptional activation of heat shock genes in primary cultures of guinea pig gastric mucosal cells.

    PubMed

    Rokutan, K; Hirakawa, T; Teshima, S; Honda, S; Kishi, K

    1996-05-15

    When primary cultures of guinea pig gastric mucosal cells were exposed to heat (43 degree C), ethanol, hydrogen peroxide (H2O2), or diamide, heat shock proteins (HSP90, HSP70, HSP60, and HSC73) were rapidly synthesized. The extent of each HSP induction varied with the type of stress. Ethanol, H2O2, and diamide increased the syntheses of several other undefined proteins besides the HSPs. However, none of these proteins were induced by exposure to heat or the reagents, when intracellular glutathione was depleted to <10% of the control level by pretreatment with DL-buthionine-[S,R]-sulfoximine. Gel mobility shift assay using a synthetic oligonucleotide coding HSP70 heat shock element showed that glutathione depletion inhibited the heat- and the reagent-initiated activation of the heat shock factor 1 (HSF1) and did not promote the expression of HSP70 mRNA. Immunoblot analysis with antiserum against HSF1 demonstrated that the steady-state level of HSF1 was not changed in glutathione-depleted cells, but glutathione depletion inhibited the nuclear translocation of HSF1 after exposure to heat stress. These results suggest that intracellular glutathione may support early and important biochemical events in the acquisition by gastric mucosal cells of an adaptive response to irritants. PMID:8636403

  12. Inositol Depletion Restores Vesicle Transport in Yeast Phospholipid Flippase Mutants

    PubMed Central

    Yamagami, Kanako; Yamamoto, Takaharu; Sakai, Shota; Mioka, Tetsuo; Sano, Takamitsu; Igarashi, Yasuyuki; Tanaka, Kazuma

    2015-01-01

    In eukaryotic cells, type 4 P-type ATPases function as phospholipid flippases, which translocate phospholipids from the exoplasmic leaflet to the cytoplasmic leaflet of the lipid bilayer. Flippases function in the formation of transport vesicles, but the mechanism remains unknown. Here, we isolate an arrestin-related trafficking adaptor, ART5, as a multicopy suppressor of the growth and endocytic recycling defects of flippase mutants in budding yeast. Consistent with a previous report that Art5p downregulates the inositol transporter Itr1p by endocytosis, we found that flippase mutations were also suppressed by the disruption of ITR1, as well as by depletion of inositol from the culture medium. Interestingly, inositol depletion suppressed the defects in all five flippase mutants. Inositol depletion also partially restored the formation of secretory vesicles in a flippase mutant. Inositol depletion caused changes in lipid composition, including a decrease in phosphatidylinositol and an increase in phosphatidylserine. A reduction in phosphatidylinositol levels caused by partially depleting the phosphatidylinositol synthase Pis1p also suppressed a flippase mutation. These results suggest that inositol depletion changes the lipid composition of the endosomal/TGN membranes, which results in vesicle formation from these membranes in the absence of flippases. PMID:25781026

  13. Measurement of depletion-induced force in microtubule bundles

    NASA Astrophysics Data System (ADS)

    Hilitski, Fiodar; Ward, Andrew; Dogic, Zvonimir

    2014-03-01

    Microtubule (MT) bundles formed in the presence of non-adsorbing polymers - poly-ethylene glycol (PEG) or Dextran - are widely used in experimental active matter systems. However, many properties of such MT bundles have not been studied experimentally. In this work, we combine optical trapping techniques with an umbrella sampling method in order to measure the depletion force acting on individual microtubule in the axial direction within the bundle. We find depletion force is independent of bundle overlap length and measure its magnitude to be on the order of tens of kB/T μm. We explore the dependence of the depletion force on concentration of depletant (PEG 20K) as well as K+ ions (necessary for screening electrostatic repulsion between MT filaments). We also verify additivity of depletion interaction and confirm that force is increased by a factor of two for three-MT bundles. Additionally, our experimental technique allows us to probe interactions between MTs within the bundle. Experimental data suggests that filaments in the bundle interact only hydrodynamically when depletant concentrations are low enough; however, we observe onset of solid-like friction when osmotic pressure is increased above a certain threshold.

  14. Arginine depletion increases susceptibility to serious infections in preterm newborns

    PubMed Central

    Badurdeen, Shiraz; Mulongo, Musa; Berkley, James A.

    2015-01-01

    Preterm newborns are highly susceptible to bacterial infections. This susceptibility is regarded as being due to immaturity of multiple pathways of the immune system. However, it is unclear whether a mechanism that unifies these different, suppressed pathways exists. Here, we argue that the immune vulnerability of the preterm neonate is critically related to arginine depletion. Arginine, a “conditionally essential” amino acid, is depleted in acute catabolic states, including sepsis. Its metabolism is highly compartmentalized and regulated, including by arginase-mediated hydrolysis. Recent data suggest that arginase II-mediated arginine depletion is essential for the innate immune suppression that occurs in newborn models of bacterial challenge, impairing pathways critical for the immune response. Evidence that arginine depletion mediates protection from immune activation during first gut colonization suggests a regulatory role in controlling gut-derived pathogens. Clinical studies show that plasma arginine is depleted during sepsis. In keeping with animal studies, small clinical trials of L-arginine supplementation have shown benefit in reducing necrotizing enterocolitis in premature neonates. We propose a novel, broader hypothesis that arginine depletion during bacterial challenge is a key factor limiting the neonate's ability to mount an adequate immune response, contributing to the increased susceptibility to infections, particularly with respect to gut-derived sepsis. PMID:25360828

  15. Genetics Home Reference: MPV17-related hepatocerebral mitochondrial DNA depletion syndrome

    MedlinePlus

    ... mitochondrial DNA depletion syndrome MPV17-related hepatocerebral mitochondrial DNA depletion syndrome Enable Javascript to view the expand/ ... All Close All Description MPV17 -related hepatocerebral mitochondrial DNA depletion syndrome is an inherited disorder that can ...

  16. Genetics Home Reference: TK2-related mitochondrial DNA depletion syndrome, myopathic form

    MedlinePlus

    ... DNA depletion syndrome, myopathic form TK2-related mitochondrial DNA depletion syndrome, myopathic form Enable Javascript to view ... Open All Close All Description TK2 -related mitochondrial DNA depletion syndrome, myopathic form ( TK2 -MDS) is an ...

  17. Quantum convolutional codes derived from constacyclic codes

    NASA Astrophysics Data System (ADS)

    Yan, Tingsu; Huang, Xinmei; Tang, Yuansheng

    2014-12-01

    In this paper, three families of quantum convolutional codes are constructed. The first one and the second one can be regarded as a generalization of Theorems 3, 4, 7 and 8 [J. Chen, J. Li, F. Yang and Y. Huang, Int. J. Theor. Phys., doi:10.1007/s10773-014-2214-6 (2014)], in the sense that we drop the constraint q ≡ 1 (mod 4). Furthermore, the second one and the third one attain the quantum generalized Singleton bound.

  18. Huffman coding in advanced audio coding standard

    NASA Astrophysics Data System (ADS)

    Brzuchalski, Grzegorz

    2012-05-01

    This article presents several hardware architectures of Advanced Audio Coding (AAC) Huffman noiseless encoder, its optimisations and working implementation. Much attention has been paid to optimise the demand of hardware resources especially memory size. The aim of design was to get as short binary stream as possible in this standard. The Huffman encoder with whole audio-video system has been implemented in FPGA devices.

  19. Coded aperture computed tomography

    NASA Astrophysics Data System (ADS)

    Choi, Kerkil; Brady, David J.

    2009-08-01

    Diverse physical measurements can be modeled by X-ray transforms. While X-ray tomography is the canonical example, reference structure tomography (RST) and coded aperture snapshot spectral imaging (CASSI) are examples of physically unrelated but mathematically equivalent sensor systems. Historically, most x-ray transform based systems sample continuous distributions and apply analytical inversion processes. On the other hand, RST and CASSI generate discrete multiplexed measurements implemented with coded apertures. This multiplexing of coded measurements allows for compression of measurements from a compressed sensing perspective. Compressed sensing (CS) is a revelation that if the object has a sparse representation in some basis, then a certain number, but typically much less than what is prescribed by Shannon's sampling rate, of random projections captures enough information for a highly accurate reconstruction of the object. This paper investigates the role of coded apertures in x-ray transform measurement systems (XTMs) in terms of data efficiency and reconstruction fidelity from a CS perspective. To conduct this, we construct a unified analysis using RST and CASSI measurement models. Also, we propose a novel compressive x-ray tomography measurement scheme which also exploits coding and multiplexing, and hence shares the analysis of the other two XTMs. Using this analysis, we perform a qualitative study on how coded apertures can be exploited to implement physical random projections by "regularizing" the measurement systems. Numerical studies and simulation results demonstrate several examples of the impact of coding.

  20. Report number codes

    SciTech Connect

    Nelson, R.N.

    1985-05-01

    This publication lists all report number codes processed by the Office of Scientific and Technical Information. The report codes are substantially based on the American National Standards Institute, Standard Technical Report Number (STRN)-Format and Creation Z39.23-1983. The Standard Technical Report Number (STRN) provides one of the primary methods of identifying a specific technical report. The STRN consists of two parts: The report code and the sequential number. The report code identifies the issuing organization, a specific program, or a type of document. The sequential number, which is assigned in sequence by each report issuing entity, is not included in this publication. Part I of this compilation is alphabetized by report codes followed by issuing installations. Part II lists the issuing organization followed by the assigned report code(s). In both Parts I and II, the names of issuing organizations appear for the most part in the form used at the time the reports were issued. However, for some of the more prolific installations which have had name changes, all entries have been merged under the current name.

  1. Cross sections for fuel depletion and radioisotope production calculations in TRIGA reactors

    SciTech Connect

    Aguilar, H.F.; Mazon, R.R.

    1994-07-01

    For TRIGA Reactors, the fuel depletion and isotopic inventory calculations, depends on the computer code and in the cross sections of some important actinides used. Among these we have U-235, U-238, Pu-239, Pu-240 and Pu-241. We choose ORIGEN2, a code with a good reputation in this kind of calculations, we observed the cross sections for these actinides in the libraries that we have (PWR's and BWR), the fission cross section for U-235 was about 50 barns. We used a PWR library and our results were not satisfactory, specially for standard elements. We decided to calculate cross sections more suitable for our reactor, for that purpose we simulate the standard and FLIP TRIGA cells with the transport code WIMS. We used the fuel average flux and COLAPS (a home made program), to generate suitable cross sections for ORIGEN2, by collapsing the WIMS library cross sections of these nuclides. For the radioisotope production studies using the Central Thimble, we simulate the A and B rings and used the A average flux to collapse cross sections. For these studies, the required nuclides sometimes are not present in WIMS library, for them we are planning to process the ENDF/B data, with NJOY system, and include the cross sections to WIMS library or to collapse them using the appropriate average-flux and the program COLAPS. (author)

  2. TRANSF code user manual

    SciTech Connect

    Weaver, H.J.

    1981-11-01

    The TRANSF code is a semi-interactive FORTRAN IV program which is designed to calculate the model parameters of a (structural) system by performing a least square parameter fit to measured transfer function data. The code is available at LLNL on both the 7600 and the Cray machines. The transfer function data to be fit is read into the code via a disk file. The primary mode of output is FR80 graphics, although, it is also possible to have results written to either the TTY or to a disk file.

  3. Ego depletion decreases trust in economic decision making

    PubMed Central

    Ainsworth, Sarah E.; Baumeister, Roy F.; Vohs, Kathleen D.; Ariely, Dan

    2014-01-01

    Three experiments tested the effects of ego depletion on economic decision making. Participants completed a task either requiring self-control or not. Then participants learned about the trust game, in which senders are given an initial allocation of $10 to split between themselves and another person, the receiver. The receiver receives triple the amount given and can send any, all, or none of the tripled money back to the sender. Participants were assigned the role of the sender and decided how to split the initial allocation. Giving less money, and therefore not trusting the receiver, is the safe, less risky response. Participants who had exerted self-control and were depleted gave the receiver less money than those in the non-depletion condition (Experiment 1). This effect was replicated and moderated in two additional experiments. Depletion again led to lower amounts given (less trust), but primarily among participants who were told they would never meet the receiver (Experiment 2) or who were given no information about how similar they were to the receiver (Experiment 3). Amounts given did not differ for depleted and non-depleted participants who either expected to meet the receiver (Experiment 2) or were led to believe that they were very similar to the receiver (Experiment 3). Decreased trust among depleted participants was strongest among neurotics. These results imply that self-control facilitates behavioral trust, especially when no other cues signal decreased social risk in trusting, such as if an actual or possible relationship with the receiver were suggested. PMID:25013237

  4. Coordinated airborne and satellite measurements of equatorial plasma depletions

    SciTech Connect

    Weber, E.J.; Brinton, H.C.; Buchau, J.; Moore, J.G.

    1982-12-01

    A series of experiments was conducted in December 1979 to investigate the structure of plasma depletions in the low latitude, nightime ionosphere. The measurements included all sky imaging photometer (ASIP), ionosonde and amplitude scintillation observations from the AFGL Airborne Ionospheric Observatory (AIO), and in situ ion density measurements from the Atmosphere Explorer (AE-E) Bennett Ion Mass Spectrometer (BIMS). The AIO performed two flights along the Ascension Island (-18/sup 0/ MLAT) magnetic meridian: one in the southern hemisphere and one near the Ascension conjugate point in the northern hemisphere. During these flights, measurements from the AE-E satellite at 434 km altitude are compared with simultaneous remote ionospheric measurements from the AIO. Density biteouts of approximately one order of magnitude in the dominant ion O/sup +/, were mapped to lower altitudes along magnetic field lines for comparison with 6300-A and 7774-A O I airglow depletions. Because of the different airglow production mechanisms (dissociative recombination of O/sup +//sub 2/ for 6300 A and radiative recombination of O/sup +/ for 7774 A) the 6300-A depletions reflect plasma depletions near the bottomside of the F layer, while those at 7774 A are located near the peak of the layer. The O/sup +/ biteouts map directly into the 7774-A airglow depletions in the same hemisphere and also when traced into the opposite hemisphere, which indicates magnetic flux tube alignment over north-south distances of approx.2220 km. The 6300-A (bottomside) depletions are wider in longitude than the 7774-A (F-peak) depletions near the equatorward edge of the Appleton anomaly. This difference in topside and bottomside structure is used to infer large-scale structure near the anomaly and to relate this to structure, commonly observed near the magnetic equator by the ALTAIR radar.

  5. FORTRAN code-evaluation system

    NASA Technical Reports Server (NTRS)

    Capps, J. D.; Kleir, R.

    1977-01-01

    Automated code evaluation system can be used to detect coding errors and unsound coding practices in any ANSI FORTRAN IV source code before they can cause execution-time malfunctions. System concentrates on acceptable FORTRAN code features which are likely to produce undesirable results.

  6. FAST2 Code validation

    SciTech Connect

    Wilson, R.E.; Freeman, L.N.; Walker, S.N.

    1995-09-01

    The FAST2 Code which is capable of determining structural loads of a flexible, teetering, horizontal axis wind turbine is described and comparisons of calculated loads with test data at two wind speeds for the ESI-80 are given. The FAST2 Code models a two-bladed HAWT with degrees of freedom for blade flap, teeter, drive train flexibility, yaw, and windwise and crosswind tower motion. The code allows blade dimensions, stiffness, and weights to differ and models tower shadow, wind shear, and turbulence. Additionally, dynamic stall is included as are delta-3 and an underslung rotor. Load comparisons are made with ESI-80 test data in the form of power spectral density, rainflow counting, occurrence histograms and azimuth averaged bin plots. It is concluded that agreement between the FAST2 Code and test results is good.

  7. Compressible Astrophysics Simulation Code

    Energy Science and Technology Software Center (ESTSC)

    2007-07-18

    This is an astrophysics simulation code involving a radiation diffusion module developed at LLNL coupled to compressible hydrodynamics and adaptive mesh infrastructure developed at LBNL. One intended application is to neutrino diffusion in core collapse supernovae.

  8. Seals Flow Code Development

    NASA Technical Reports Server (NTRS)

    1991-01-01

    In recognition of a deficiency in the current modeling capability for seals, an effort was established by NASA to develop verified computational fluid dynamic concepts, codes, and analyses for seals. The objectives were to develop advanced concepts for the design and analysis of seals, to effectively disseminate the information to potential users by way of annual workshops, and to provide experimental verification for the models and codes under a wide range of operating conditions.

  9. Robust Nonlinear Neural Codes

    NASA Astrophysics Data System (ADS)

    Yang, Qianli; Pitkow, Xaq

    2015-03-01

    Most interesting natural sensory stimuli are encoded in the brain in a form that can only be decoded nonlinearly. But despite being a core function of the brain, nonlinear population codes are rarely studied and poorly understood. Interestingly, the few existing models of nonlinear codes are inconsistent with known architectural features of the brain. In particular, these codes have information content that scales with the size of the cortical population, even if that violates the data processing inequality by exceeding the amount of information entering the sensory system. Here we provide a valid theory of nonlinear population codes by generalizing recent work on information-limiting correlations in linear population codes. Although these generalized, nonlinear information-limiting correlations bound the performance of any decoder, they also make decoding more robust to suboptimal computation, allowing many suboptimal decoders to achieve nearly the same efficiency as an optimal decoder. Although these correlations are extremely difficult to measure directly, particularly for nonlinear codes, we provide a simple, practical test by which one can use choice-related activity in small populations of neurons to determine whether decoding is suboptimal or optimal and limited by correlated noise. We conclude by describing an example computation in the vestibular system where this theory applies. QY and XP was supported by a grant from the McNair foundation.

  10. HIDUTYDRV Code, A Fuel Product Margin Tool

    SciTech Connect

    Krammen, Michael A.; Karoutas, Zeses E.; Grill, Steven F.; Sutharshan, Balendra

    2007-07-01

    HIDUTYDRV is a computer code currently used in core design to model the best estimate steady-state fuel rod corrosion performance for Westinghouse's CE-design 14x14 and 16x16 fuel. The fuel rod oxide thickness, sub-cooled nucleate boiling (referred to as mass evaporation or steaming), and fuel duty indices can be predicted for individual rods or up to every fuel rod in the quarter core at every nuclear fuel management depletion time-step as a function of axial elevation within the core. Best estimate operating margins for fuel components whose performance depends on the local power and thermal hydraulic conditions are candidates for analysis with HIDUTYDRV. HIDUTYDRV development will focus on fuel component parameters associated with known leakers for addressing INPO goals to eliminate fuel leakers by 2010. (authors)

  11. Effective delivery of chemotherapeutic nanoparticles by depleting host Kupffer cells.

    PubMed

    Ohara, Yusuke; Oda, Tatsuya; Yamada, Keiichi; Hashimoto, Shinji; Akashi, Yoshimasa; Miyamoto, Ryoichi; Kobayashi, Akihiko; Fukunaga, Kiyoshi; Sasaki, Ryoko; Ohkohchi, Nobuhiro

    2012-11-15

    Although chemotherapeutic nanoparticles would confer various advantages, the majority of administrated nanoparticles are known to be spoiled by the reticuloendothelial system (RES). Intending to more effectively deliver therapeutic nanoparticles to target regions in vivo, host RES, especially Kupffer cells in the liver, have been depleted ahead of drug administration. To demonstrate this hypothesis, clodronate liposomes were preinjected into BALB/c nude mice for depletion of Kupffer cells 2 days before, and pegylated liposomal doxorubicin (Doxil) at the doses of 1.25, 2.5 and 5.0 mg/kg was administered. As a result, doxorubicin accumulation in the liver was decreased from 36 to 26% injected dose/organ by the Kupffer cells depletion, and consequently, the plasma concentration of doxorubicin was significantly enhanced threefold (from 11 to 33 μg/mL) on day 1 at 1.25 mg/kg-dose group. Doxorubicin accumulation in the tumor was increased from 0.78 to 3.0 μg/g-tissue on day 3, and tumor growth inhibition by Doxil was significantly boosted (tumor volumes from 751 to 482 mm(3) on day 24) by the Kupffer cells depletion. In conclusion, Kupffer cells depletion by clodronate liposomes enhanced the plasma concentration and antitumor effects of Doxil, and would be widely applicable for various clinical cancer chemotherapies using nanoparticles. PMID:22362271

  12. Stream depletion in alluvial valleys using the SDF semianalytical model.

    PubMed

    Miller, Calvin D; Durnford, Deanna; Halstead, Mary R; Altenhofen, Jon; Flory, Val

    2007-01-01

    A semianalytical method commonly used for quantifying stream depletion caused by ground water pumping was reviewed for applicability in narrow alluvial aquifers. This stream depletion factor (SDF) method is based on the analytic Glover model, but uses a numerical model-derived input parameter, called the SDF, to partly account for mathematically nonideal conditions such as variable transmissivity and nearby aquifer boundaries. Using the SDF can improve and simplify depletion estimates. However, the method's approximations introduce error that increases with proximity to the impermeable aquifer boundary. This article reviews the history of the method and its assumptions. New stream depletion response curves are presented as functions of well position within bounded aquifers. A simple modification to modeled SDF values is proposed that allows the impermeable boundary to be accounted for with image wells, but without overaccounting for boundary effects that are already reflected in modeled SDFs. It is shown that SDFs for locations closer to the river than to the aquifer boundary do not reflect impermeable-boundary effects, and thus need no modification, and boundary effects in the other portion of the aquifer follow a predictable removable pattern. This method is verified by comparing response curves using modified SDFs with response curves from an extensively calibrated numerical model of a managed ground water recharge site. The modification improves SDF-based stream depletion estimates in bounded aquifers while still benefiting from the additional information contained in SDF maps and retaining their value as standardized references for water rights administration. PMID:17600582

  13. Reentrant phase transitions from depletion: colloidal crystals to flocculation

    NASA Astrophysics Data System (ADS)

    Feng, Lang; Laderman, Bezia; Sacanna, Stefano; Chaikin, Paul

    2014-03-01

    Conventional depletion is supposed to be temperature independent. However, we find that many typical colloid-depletion systems show remarkable phenomena as temperature is varied. 1 μm polystyrene spheres in water are known to form colloidal crystals when PEO is added as a depletant. When this system is heated the crystal melts at a first critical temperature T1 ~ 60 C , and then at higher temperature T2 ~ 70 C the colloids flocculate. We argue that a weak temperature-dependent interaction between polymer and colloid is responsible for the observed phenomena: crystals form when the colloid-polymer interaction is repulsive, flocculation occurs when the interaction is attractive, and melting occurs in between when both phases are frustrated. The melted phase occurs due to an unexpected cancelation when combining both entropic and enthalpic attractions. We propose a simple statistical model to map out the observed transitions and fill the theoretical gap between the two established scenarios for colloid-polymer systems, namely depletion and flocculation. We have seen the same temperature dependent phenomena for TPM, PS and silica spheres with PEO and dextran as depletants. Our discovery provides a fundamental understanding of the polymer-colloid system and opens new possibilities for colloidal self-assembly and temperature-controlled viscoelastic materials.

  14. Antarctic winter mercury and ozone depletion events over sea ice

    NASA Astrophysics Data System (ADS)

    Nerentorp Mastromonaco, M.; Gårdfeldt, K.; Jourdain, B.; Abrahamsson, K.; Granfors, A.; Ahnoff, M.; Dommergue, A.; Méjean, G.; Jacobi, H.-W.

    2016-03-01

    During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quickly transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during Antarctic winter over sea ice areas, leading to additional deposition of mercury. Over four months in the Weddell Sea we measured gaseous elemental, oxidized, and particulate-bound mercury, as well as ozone in the troposphere and total and elemental mercury concentrations in snow, demonstrating a series of depletion and deposition events between July and September. The winter depletions in July were characterized by stronger correlations between mercury and ozone and larger formation of particulate-bound mercury in air compared to later spring events. It appears that light at large solar zenith angles is sufficient to initiate the photolytic formation of halogen radicals. We also propose a dark mechanism that could explain observed events in air masses coming from dark regions. Br2 that could be the main actor in dark conditions was possibly formed in high concentrations in the marine boundary layer in the dark. These high concentrations may also have caused the formation of high concentrations of CHBr3 and CH2I2 in the top layers of the Antarctic sea ice observed during winter. These new findings show that the extent of depletion events is larger than previously believed and that winter depletions result in additional deposition of mercury that could be transferred to marine and terrestrial ecosystems.

  15. Dynamics of spinal microglia repopulation following an acute depletion

    PubMed Central

    Yao, Yao; Echeverry, Stefania; Shi, Xiang Qun; Yang, Mu; Yang, Qiu Zi; Wang, Guan Yun Frances; Chambon, Julien; Wu, Yi Chen; Fu, Kai Yuan; De Koninck, Yves; Zhang, Ji

    2016-01-01

    Our understanding on the function of microglia has been revolutionized in the recent 20 years. However, the process of maintaining microglia homeostasis has not been fully understood. In this study, we dissected the features of spinal microglia repopulation following an acute partial depletion. By injecting intrathecally Mac-1-saporin, a microglia selective immunotoxin, we ablated 50% microglia in the spinal cord of naive mice. Spinal microglia repopulated rapidly and local homeostasis was re-established within 14 days post-depletion. Mac-1-saporin treatment resulted in microglia cell proliferation and circulating monocyte infiltration. The latter is indeed part of an acute, transient inflammatory reaction that follows cell depletion, and was characterized by an increase in the expression of inflammatory molecules and by the breakdown of the blood spinal cord barrier. During this period, microglia formed cell clusters and exhibited a M1-like phenotype. MCP-1/CCR2 signaling was essential in promoting this depletion associated spinal inflammatory reaction. Interestingly, ruling out MCP-1-mediated secondary inflammation, including blocking recruitment of monocyte-derived microglia, did not affect depletion-triggered microglia repopulation. Our results also demonstrated that newly generated microglia kept their responsiveness to peripheral nerve injury and their contribution to injury-associated neuropathic pain was not significantly altered. PMID:26961247

  16. The effect of uncomplicated potassium depletion on urine acidification

    PubMed Central

    Tannen, Richard L.

    1970-01-01

    Studies were performed on normal human subjects to determine the effects of potassium depletion on urine acidification. Depletion was induced by ingestion of a low potassium diet either alone or in combination with a potassium-binding resin, and the response of each subject to an acute ammonium chloride load in the potassium-depleted state was compared to his normal response. Urine pH was significantly higher during potassium deficiency if sufficient potassium depletion had been induced. No differences in blood acid-base parameters, urinary flow rate, or urinary fixed buffer excretion rate were found to account for this change; however, the increase in urine pH was accompanied by a concomitant increase in net acid and ammonium excretion. It is proposed that these changes during potassium depletion reflect an increase in ammonia diffusion into the urine, presumably as a result of increased renal ammonia production. In addition, it is speculated that changes in ammonia metabolism may be a physiologic control mechanism for potassium conservation. PMID:5443182

  17. About ozone depletion in stratosphere over Brazil in last decade

    NASA Astrophysics Data System (ADS)

    Martin, Inácio M.; Imai, Takeshi; Seguchi, Tomio

    The depletion of stratospheric ozone, resulting from the emission of chlorofluorocarbons (CFCs), has become a major issue since 1980. The decrease in stratospheric ozone over the polar regions has been pronounced at the South Pole than at the North Pole. In mid-latitude and equatorial regions, ozone depletion becomes less important; it depends on seasonal effects and on the characteristics of a particular region. The detailed mechanism by which the polar ozone holes form is different from that for the mid-latitude thinning, but the most important process in both trends is the catalytic destruction of ozone by atomic chlorine and bromine. The main source of these halogen atoms in the stratosphere is photodissociation of CFC compounds, commonly called freons, and of bromofluorocarbon compounds known as halons. These compounds are transported into the stratosphere after being emitted at the surface. Both ozone depletion mechanisms strengthened as emissions of CFCs and halons increased [1]. Measurements of stratospheric ozone carried out on several locations in Brazil and on the South Pole in the last decade (1996-2005), using detectors placed on ground, stratospheric balloons and Earth Probe TOMS satellites, are presented here. Detailed series analysis from 1980 up to the present describes a mean ozone depletion of 4[1] http://en.wikipedia.org/wiki/Ozone/depletion.

  18. Global Depletion of Groundwater Resources: Past and Future Analyses

    NASA Astrophysics Data System (ADS)

    Bierkens, M. F.; de Graaf, I. E. M.; Van Beek, L. P.; Wada, Y.

    2014-12-01

    Globally, about 17% of the crops are irrigated, yet irrigation accounts for 40% of the global food production. As more than 40% of irrigation water comes from groundwater, groundwater abstraction rates are large and exceed natural recharge rates in many regions of the world, thus leading to groundwater depletion. In this paper we provide an overview of recent research on global groundwater depletion. We start with presenting various estimates of global groundwater depletion, both from flux based as well as volume based methods. We also present estimates of the contribution of non-renewable groundwater to irrigation water consumption and how this contribution developed during the last 50 years. Next, using a flux based method, we provide projections of groundwater depletion for the coming century under various socio-economic and climate scenarios. As groundwater depletion contributes to sea-level rise, we also provide estimates of this contribution from the past as well as for future scenarios. Finally, we show recent results of groundwater level changes and change in river flow as a result of global groundwater abstractions as obtained from a global groundwater flow model.

  19. Nucleosynthesis in the Hyades Open Cluster: Evidence for the Enhanced Depletion of 12C

    NASA Astrophysics Data System (ADS)

    Schuler, Simon C.; King, Jeremy R.; The, Lih-Sin

    2010-03-01

    We present the results of a light element abundance analysis of three solar-type main sequence (MS) dwarfs and three red giant branch (RGB) clump stars in the Hyades open cluster using high-resolution and high signal-to-noise spectroscopy. The CNO abundances of each group (MS or RGB) are in excellent star-to-star agreement and confirm that the giants have undergone first dredge-up mixing. The observed abundances are compared to predictions of a standard stellar model based on the Clemson-American University of Beirut (CAUB) stellar evolution code. The model reproduces the observed evolution of the N and O abundances, as well as the previously derived 12C/13C ratio, but it fails to predict the observed level of 12C depletion in the giants. More tellingly, the sum of the observed giant CNO abundances does not equal that of the dwarfs.

  20. Cadmium Depletion Impacts on Hardening Neutron6 Spectrum for Advanced Fuel Testing in ATR

    SciTech Connect

    Gray S. Chang

    2011-05-01

    For transmuting long-lived isotopes contained in spent nuclear fuel into shorter-lived fission products effectively is in a fast neutron spectrum reactor. In the absence of a fast spectrum test reactor in the United States of America (USA), initial irradiation testing of candidate fuels can be performed in a thermal test reactor that has been modified to produce a test region with a hardened neutron spectrum. A test region is achieved with a Cadmium (Cd) filter which can harden the neutron spectrum to a spectrum similar (although still somewhat softer) to that of the liquid metal fast breeder reactor (LMFBR). A fuel test loop with a Cd-filter has been installed within the East Flux Trap (EFT) of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL). A detailed comparison analyses between the cadmium (Cd) filter hardened neutron spectrum in the ATR and the LMFBR fast neutron spectrum have been performed using MCWO. MCWO is a set of scripting tools that are used to couple the Monte Carlo transport code MCNP with the isotope depletion and buildup code ORIGEN-2.2. The MCWO-calculated results indicate that the Cd-filter can effectively flatten the Rim-Effect and reduce the linear heat rate (LHGR) to meet the advanced fuel testing project requirements at the beginning of irradiation (BOI). However, the filtering characteristics of Cd as a strong absorber quickly depletes over time, and the Cd-filter must be replaced for every two typical operating cycles within the EFT of the ATR. The designed Cd-filter can effectively depress the LHGR in experimental fuels and harden the neutron spectrum enough to adequately flatten the Rim Effect in the test region.

  1. Resource depletion does not influence prospective memory in college students

    PubMed Central

    Talley Shelton, Jill; Cahill, Michael J.; Mullet, Hillary G.; Scullin, Michael K.; Einstein, Gilles O.; McDaniel, Mark A.

    2013-01-01

    This paper reports an experiment designed to investigate the potential influence of prior acts of self-control on subsequent prospective memory performance. College undergraduates (n = 146) performed either a cognitively depleting initial task (e.g., mostly incongruent Stroop task) or a less resource-consuming version of that task (e.g., all congruent Stroop task). Subsequently, participants completed a prospective memory task that required attentionally demanding monitoring processes. The results demonstrated that prior acts of self-control do not impair the ability to execute a future intention in college-aged adults. We conceptually replicated these results in three additional depletion and prospective memory experiments. This research extends a growing number of studies demonstrating the boundary conditions of the resource depletion effect in cognitive tasks. PMID:24021851

  2. Tunable depletion potentials driven by shape variation of surfactant micelles

    NASA Astrophysics Data System (ADS)

    Gratale, Matthew D.; Still, Tim; Matyas, Caitlin; Davidson, Zoey S.; Lobel, Samuel; Collings, Peter J.; Yodh, A. G.

    2016-05-01

    Depletion interaction potentials between micron-sized colloidal particles are induced by nanometer-scale surfactant micelles composed of hexaethylene glycol monododecyl ether (C12E6 ), and they are measured by video microscopy. The strength and range of the depletion interaction is revealed to arise from variations in shape anisotropy of the surfactant micelles. This shape anisotropy increases with increasing sample temperature. By fitting the colloidal interaction potentials to theoretical models, we extract micelle length and shape anisotropy as a function of temperature. This work introduces shape anisotropy tuning as a means to control interparticle interactions in colloidal suspensions, and it shows how the interparticle depletion potentials of micron-scale objects can be employed to probe the shape and size of surrounding macromolecules at the nanoscale.

  3. Depleted uranium as a backfill for nuclear fuel waste package

    DOEpatents

    Forsberg, Charles W.

    1998-01-01

    A method for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotopically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package.

  4. Effect of Shim Arm Depletion in the NBSR

    SciTech Connect

    Hanson A. H.; Brown N.; Diamond, D.J.

    2013-02-22

    The cadmium shim arms in the NBSR undergo burnup during reactor operation and hence, require periodic replacement. Presently, the shim arms are replaced after every 25 cycles to guarantee they can maintain sufficient shutdown margin. Two prior reports document the expected change in the 113Cd distribution because of the shim arm depletion. One set of calculations was for the present high-enriched uranium fuel and the other for the low-enriched uranium fuel when it was in the COMP7 configuration (7 inch fuel length vs. the present 11 inch length). The depleted 113Cd distributions calculated for these cores were applied to the current design for an equilibrium low-enriched uranium core. This report details the predicted effects, if any, of shim arm depletion on the shim arm worth, the shutdown margin, power distributions and kinetics parameters.

  5. International aspects of restrictions of ozone-depleting substances

    SciTech Connect

    McDonald, S.C.

    1989-10-01

    This report summarizes international efforts to protect stratospheric ozone. Also included in this report is a discussion of activities in other countries to meet restrictions in the production and use of ozone-depleting substances. Finally, there is a brief presentation of trade and international competitiveness issues relating to the transition to alternatives for the regulated chlorofluorocarbons (CFCs) and halons. The stratosphere knows no international borders. Just as the impact of reduced stratospheric ozone will be felt internationally, so protection of the ozone layer is properly an international effort. Unilateral action, even by a country that produces and used large quantities of ozone-depleting substances, will not remedy the problem of ozone depletion if other countries do not follow suit. 32 refs., 7 tabs.

  6. Programmable nanometer-scale electrolytic metal deposition and depletion

    DOEpatents

    Lee, James Weifu [Oak Ridge, TN; Greenbaum, Elias [Oak Ridge, TN

    2002-09-10

    A method of nanometer-scale deposition of a metal onto a nanostructure includes the steps of: providing a substrate having thereon at least two electrically conductive nanostructures spaced no more than about 50 .mu.m apart; and depositing metal on at least one of the nanostructures by electric field-directed, programmable, pulsed electrolytic metal deposition. Moreover, a method of nanometer-scale depletion of a metal from a nanostructure includes the steps of providing a substrate having thereon at least two electrically conductive nanostructures spaced no more than about 50 .mu.m apart, at least one of the nanostructures having a metal disposed thereon; and depleting at least a portion of the metal from the nanostructure by electric field-directed, programmable, pulsed electrolytic metal depletion. A bypass circuit enables ultra-finely controlled deposition.

  7. Depleted uranium as a backfill for nuclear fuel waste package

    DOEpatents

    Forsberg, C.W.

    1998-11-03

    A method is described for packaging spent nuclear fuel for long-term disposal in a geological repository. At least one spent nuclear fuel assembly is first placed in an unsealed waste package and a depleted uranium fill material is added to the waste package. The depleted uranium fill material comprises flowable particles having a size sufficient to substantially fill any voids in and around the assembly and contains isotopically-depleted uranium in the +4 valence state in an amount sufficient to inhibit dissolution of the spent nuclear fuel from the assembly into a surrounding medium and to lessen the potential for nuclear criticality inside the repository in the event of failure of the waste package. Last, the waste package is sealed, thereby substantially reducing the release of radionuclides into the surrounding medium, while simultaneously providing radiation shielding and increased structural integrity of the waste package. 6 figs.

  8. Resource depletion does not influence prospective memory in college students.

    PubMed

    Shelton, Jill Talley; Cahill, Michael J; Mullet, Hillary G; Scullin, Michael K; Einstein, Gilles O; McDaniel, Mark A

    2013-12-01

    This paper reports an experiment designed to investigate the potential influence of prior acts of self-control on subsequent prospective memory performance. College undergraduates (n=146) performed either a cognitively depleting initial task (e.g., mostly incongruent Stroop task) or a less resource-consuming version of that task (e.g., all congruent Stroop task). Subsequently, participants completed a prospective memory task that required attentionally demanding monitoring processes. The results demonstrated that prior acts of self-control do not impair the ability to execute a future intention in college-aged adults. We conceptually replicated these results in three additional depletion and prospective memory experiments. This research extends a growing number of studies demonstrating the boundary conditions of the resource depletion effect in cognitive tasks. PMID:24021851

  9. Observations of ozone depletion associated with solar proton events

    NASA Technical Reports Server (NTRS)

    Mcpeters, R. D.; Jackman, C. H.; Stassinopoulos, E. G.

    1981-01-01

    Ozone profiles from the solar proton events (SPE) of January and September 1971 and August 1972 were obtained after the backscattered ultraviolet (BUV) measured radiances were corrected for the direct effects of protons on the instrument. The SPE of August 1972 produced an ozone depletion of 15% at 42 km that persisted for one month in both northern and southern polar regions. This long recovery time indicates that NO(x) was produced in a quantity sufficient to alter the ozone chemistry. The two SPE in 1971 were of moderate size, but produced ozone depletions of 10-30% at 50 km with a 36 hour recovery time. This rapid recovery is consistent with the assumption that HO(x) is responsible for altering the ozone chemistry (Weeks et al., 1972). The magnitude of the observed depletion, however, exceeds that predicted by the chemical models.

  10. Coherent quantum depletion of an interacting atom condensate

    PubMed Central

    Kira, M.

    2015-01-01

    Sufficiently strong interactions promote coherent quantum transitions in spite of thermalization and losses, which are the adversaries of delicate effects such as reversibility and correlations. In atomic Bose–Einstein condensates (BECs), strong atom–atom interactions can eject atoms from the BEC to the normal component, yielding quantum depletion instead of temperature depletion. A recent experiment has already been verified to overcome losses. Here I show that it also achieves coherent quantum-depletion dynamics in a BEC swept fast enough from weak to strong atom–atom interactions. The elementary coherent process first excites the normal component into a liquid state that evolves into a spherical shell state, where the atom occupation peaks at a finite momentum to shield 50% of the BEC atoms from annihilation. The identified coherent processes resemble ultrafast semiconductor excitations expanding the scope of BEC explorations to many-body non-equilibrium studies. PMID:25767044

  11. Tuning of depletion interaction in nanoparticle-surfactant systems

    SciTech Connect

    Ray, D. Aswal, V. K.

    2014-04-24

    The interaction of anionic silica nanoparticles (Ludox LS30) and non-ionic surfactants decaethylene glycol monododecylether (C12E10) without and with anionic sodium dodecyl sulfate (SDS) in aqueous electrolyte solution has been studied by small-angle neutron scattering (SANS). The measurements have been carried out for fixed concentrations of nanoparticle (1 wt%), surfactants (1 wt%) and electrolyte (0.1 M NaCl). Each of these nanoparticlesurfactant systems has been examined for different contrast conditions where individual components (nanoparticle or surfactant) are made visible. It is observed that the nanoparticle-C12E10 system leads to the depletion-induced aggregation of nanoparticles. The system however behaves very differently on addition of SDS where depletion interaction gets suppressed and aggregation of nanoparticles can be prevented. We show that C12E10 and SDS form mixed micelles and the charge on these micelles plays important role in tuning the depletion interaction.

  12. Depletion induced clustering of red blood cells in microchannels

    NASA Astrophysics Data System (ADS)

    Wagner, Christian; Brust, Mathias; Podgorski, Thomas; Coupier, Gwennou

    2012-11-01

    The flow properties of blood are determined by the physical properties of its main constituents, the red blood cells (RBC's). At low shear rates RBC's form aggregates, so called rouleaux. Higher shear rates can break them up and the viscosity of blood shows a shear thinning behavior. The physical origin of the rouleaux formation is not yet fully resolved and there are two competing models available. One predicts that the adhesion is induced by bridging of the plasma (macromolecular) proteins in-between two RBC's. The other is based on the depletion effect and thus predicts the absence of macromolecules in-between the cells of a rouleaux. Recent single cell force measurements by use of an AFM support strongly the depletion model. By varying the concentration of Dextran at different molecular weights we can control the adhesions strength. Measurements at low hematocrit in a microfluidic channel show that the number of size of clusters is determined by the depletion induced adhesion strength.

  13. Coherent quantum depletion of an interacting atom condensate.

    PubMed

    Kira, M

    2015-01-01

    Sufficiently strong interactions promote coherent quantum transitions in spite of thermalization and losses, which are the adversaries of delicate effects such as reversibility and correlations. In atomic Bose-Einstein condensates (BECs), strong atom-atom interactions can eject atoms from the BEC to the normal component, yielding quantum depletion instead of temperature depletion. A recent experiment has already been verified to overcome losses. Here I show that it also achieves coherent quantum-depletion dynamics in a BEC swept fast enough from weak to strong atom-atom interactions. The elementary coherent process first excites the normal component into a liquid state that evolves into a spherical shell state, where the atom occupation peaks at a finite momentum to shield 50% of the BEC atoms from annihilation. The identified coherent processes resemble ultrafast semiconductor excitations expanding the scope of BEC explorations to many-body non-equilibrium studies. PMID:25767044

  14. Radiosensitization of mouse skin by oxygen and depletion of glutathione

    SciTech Connect

    Stevens, G.; Joiner, M.; Joiner, B.

    1995-09-30

    To determine the oxygen enhancement ratio (OER) and shape of the oxygen sensitization curve of mouse foot skin, the extent to which glutathione (GSH) depletion radiosensitized skin, and the dependence of such sensitization on the ambient oxygen tension. Carbogen caused the greatest radiosensitization of skin, with a reproducible enhancement of 2.2 relative to the anoxic response. The OER of 2.2 is lower than other reports for mouse skin. This may indicate that the extremes of oxygenation were not produced, although there was no direct evidence for this. Depletion of GSH caused minimal radiosensitization when skin was irradiated under anoxic or well-oxygenated conditions. Radiosensitization by GSH depletion was maximal at intermediate oxygen tensions of 10-21% O{sub 2} in the ambient gas. Increasing the extent of GSH depletion led to increasing radiosensitization, with sensitization enhancement ratios of 1.2 and 1.1, respectively, for extensive and intermediated levels of GSH depletion. In mice exposed to 100% O{sub 2}, a significant component of skin radiosensitivity was due to diffusion of oxygen directly through the skin. Pentobarbitone anesthesia radiosensitized skin in mice exposed to 100% O{sub 2} by a factor of 1.2, but did not further sensitize skin in mice exposed to carbogen. Glutathione levels and the local oxygen tension at the time of irradiation were important determinants of mouse foot skin radiosensitivity. The extent to which GSH levels altered the radiosensitivity of skin was critically dependent on the local oxygen tension. These results have significant implications for potential clinical applications of GSH depletion. 53 refs., 7 figs., 2 tabs.

  15. Ozone depletion. (Latest citations from the NTIS database). Published Search

    SciTech Connect

    Not Available

    1993-04-01

    The bibliography contains citations concerning studies of atmospheric chemistry and modeling of ozone depletion in Antarctica, and the consequences of the depletion on ultraviolet radiation levels. The studies involve chemical reactions in the atmosphere, including temperature dynamics, possible changes in solar insolation, and effects of pollution from nitrogen, chloroflourocarbons, carbon dioxide, and methane. The studies involve references to observations of the ozonosphere and modeling of interactions worldwide, together with data on the sources of the natural and man-made pollutants. (Contains a minimum of 173 citations and includes a subject term index and title list.)

  16. Characterization of a Depleted Monolithic Active Pixel Sensor (DMAPS) prototype

    NASA Astrophysics Data System (ADS)

    Obermann, T.; Havranek, M.; Hemperek, T.; Hügging, F.; Kishishita, T.; Krüger, H.; Marinas, C.; Wermes, N.

    2015-03-01

    New monolithic pixel detectors integrating CMOS electronics and sensor on the same silicon substrate are currently explored for particle tracking in future HEP experiments, most notably at the LHC . The innovative concept of Depleted Monolithic Active Pixel Sensors (DMAPS) is based on high resistive silicon bulk material enabling full substrate depletion and the application of an electrical drift field for fast charge collection, while retaining full CMOS capability for the electronics. The technology (150 nm) used offers quadruple wells and allows to implement the pixel electronics with independently isolated N- and PMOS transistors. Results of initial studies on the charge collection and sensor performance are presented.

  17. Prioritized LT Codes

    NASA Technical Reports Server (NTRS)

    Woo, Simon S.; Cheng, Michael K.

    2011-01-01

    The original Luby Transform (LT) coding scheme is extended to account for data transmissions where some information symbols in a message block are more important than others. Prioritized LT codes provide unequal error protection (UEP) of data on an erasure channel by modifying the original LT encoder. The prioritized algorithm improves high-priority data protection without penalizing low-priority data recovery. Moreover, low-latency decoding is also obtained for high-priority data due to fast encoding. Prioritized LT codes only require a slight change in the original encoding algorithm, and no changes at all at the decoder. Hence, with a small complexity increase in the LT encoder, an improved UEP and low-decoding latency performance for high-priority data can be achieved. LT encoding partitions a data stream into fixed-sized message blocks each with a constant number of information symbols. To generate a code symbol from the information symbols in a message, the Robust-Soliton probability distribution is first applied in order to determine the number of information symbols to be used to compute the code symbol. Then, the specific information symbols are chosen uniform randomly from the message block. Finally, the selected information symbols are XORed to form the code symbol. The Prioritized LT code construction includes an additional restriction that code symbols formed by a relatively small number of XORed information symbols select some of these information symbols from the pool of high-priority data. Once high-priority data are fully covered, encoding continues with the conventional LT approach where code symbols are generated by selecting information symbols from the entire message block including all different priorities. Therefore, if code symbols derived from high-priority data experience an unusual high number of erasures, Prioritized LT codes can still reliably recover both high- and low-priority data. This hybrid approach decides not only "how to encode

  18. Coded source neutron imaging

    SciTech Connect

    Bingham, Philip R; Santos-Villalobos, Hector J

    2011-01-01

    Coded aperture techniques have been applied to neutron radiography to address limitations in neutron flux and resolution of neutron detectors in a system labeled coded source imaging (CSI). By coding the neutron source, a magnified imaging system is designed with small spot size aperture holes (10 and 100 m) for improved resolution beyond the detector limits and with many holes in the aperture (50% open) to account for flux losses due to the small pinhole size. An introduction to neutron radiography and coded aperture imaging is presented. A system design is developed for a CSI system with a development of equations for limitations on the system based on the coded image requirements and the neutron source characteristics of size and divergence. Simulation has been applied to the design using McStas to provide qualitative measures of performance with simulations of pinhole array objects followed by a quantitative measure through simulation of a tilted edge and calculation of the modulation transfer function (MTF) from the line spread function. MTF results for both 100um and 10um aperture hole diameters show resolutions matching the hole diameters.

  19. Error coding simulations

    NASA Technical Reports Server (NTRS)

    Noble, Viveca K.

    1993-01-01

    There are various elements such as radio frequency interference (RFI) which may induce errors in data being transmitted via a satellite communication link. When a transmission is affected by interference or other error-causing elements, the transmitted data becomes indecipherable. It becomes necessary to implement techniques to recover from these disturbances. The objective of this research is to develop software which simulates error control circuits and evaluate the performance of these modules in various bit error rate environments. The results of the evaluation provide the engineer with information which helps determine the optimal error control scheme. The Consultative Committee for Space Data Systems (CCSDS) recommends the use of Reed-Solomon (RS) and convolutional encoders and Viterbi and RS decoders for error correction. The use of forward error correction techniques greatly reduces the received signal to noise needed for a certain desired bit error rate. The use of concatenated coding, e.g. inner convolutional code and outer RS code, provides even greater coding gain. The 16-bit cyclic redundancy check (CRC) code is recommended by CCSDS for error detection.

  20. Error coding simulations

    NASA Astrophysics Data System (ADS)

    Noble, Viveca K.

    1993-11-01

    There are various elements such as radio frequency interference (RFI) which may induce errors in data being transmitted via a satellite communication link. When a transmission is affected by interference or other error-causing elements, the transmitted data becomes indecipherable. It becomes necessary to implement techniques to recover from these disturbances. The objective of this research is to develop software which simulates error control circuits and evaluate the performance of these modules in various bit error rate environments. The results of the evaluation provide the engineer with information which helps determine the optimal error control scheme. The Consultative Committee for Space Data Systems (CCSDS) recommends the use of Reed-Solomon (RS) and convolutional encoders and Viterbi and RS decoders for error correction. The use of forward error correction techniques greatly reduces the received signal to noise needed for a certain desired bit error rate. The use of concatenated coding, e.g. inner convolutional code and outer RS code, provides even greater coding gain. The 16-bit cyclic redundancy check (CRC) code is recommended by CCSDS for error detection.

  1. 26 CFR 1.612-1 - Basis for allowance of cost depletion.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... included in the basis for cost depletion of oil and gas property the amounts of capitalized drilling and... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Basis for allowance of cost depletion. 1.612-1... depletion. (a) In general. The basis upon which the deduction for cost depletion under section 611 is to...

  2. 26 CFR 1.612-1 - Basis for allowance of cost depletion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... included in the basis for cost depletion of oil and gas property the amounts of capitalized drilling and... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Basis for allowance of cost depletion. 1.612-1... depletion. (a) In general. The basis upon which the deduction for cost depletion under section 611 is to...

  3. 26 CFR 1.612-1 - Basis for allowance of cost depletion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... included in the basis for cost depletion of oil and gas property the amounts of capitalized drilling and... 26 Internal Revenue 7 2012-04-01 2012-04-01 false Basis for allowance of cost depletion. 1.612-1... depletion. (a) In general. The basis upon which the deduction for cost depletion under section 611 is to...

  4. Validation of SCALE and the TRITON Depletion Sequence for Gas-Cooled Reactor Analysis

    SciTech Connect

    DeHart, Mark D; Pritchard, Megan L

    2008-01-01

    The very-high-temperature reactor (VHTR) is an advanced reactor concept that uses graphite-moderated fuel and helium gas as a coolant. At present there are two primary VHTR reactor designs under consideration for development: in the pebble-bed reactor, a core is loaded with 'pebbles' consisting of 6 cm diameter spheres, while in a high-temperature gas-cooled reactor, fuel rods are placed within prismatic graphite blocks. In both systems, fuel elements (spheres or rods) are comprised of tristructural-isotropic (TRISO) fuel particles. The TRISO particles are either dispersed in the matrix of a graphite pebble for the pebble-bed design or molded into compacts/rods that are then inserted into the hexagonal graphite blocks for the prismatic concept. Two levels of heterogeneity exist in such fuel designs: (1) microspheres of TRISO particles dispersed in a graphite matrix of a cylindrical or spherical shape, and (2) neutron interactions at the rod-to-rod or sphere-to-sphere level. Such double heterogeneity (DH) provides a challenge to multigroup cross-section processing methods, which must treat each level of heterogeneity separately. A new capability to model doubly heterogeneous systems was added to the SCALE system in the release of Version 5.1. It was included in the control sequences CSAS and CSAS6, which use the Monte Carlo codes KENO V.a and KENO-VI, respectively, for three-dimensional neutron transport analyses and in the TRITON sequence, which uses the two-dimensional lattice physics code NEWT along with both versions of KENO for transport and depletion analyses. However, the SCALE 5.1 version of TRITON did not support the use of the DH approach for depletion. This deficiency has been addressed, and DH depletion will be available as an option in the upcoming release of SCALE 6. At present Oak Ridge National Laboratory (ORNL) staff are developing a set of calculations that may be used to validate SCALE for DH calculations. This paper discusses the results of

  5. Phase-coded pulse aperiodic transmitter coding

    NASA Astrophysics Data System (ADS)

    Virtanen, I. I.; Vierinen, J.; Lehtinen, M. S.

    2009-07-01

    Both ionospheric and weather radar communities have already adopted the method of transmitting radar pulses in an aperiodic manner when measuring moderately overspread targets. Among the users of the ionospheric radars, this method is called Aperiodic Transmitter Coding (ATC), whereas the weather radar users have adopted the term Simultaneous Multiple Pulse-Repetition Frequency (SMPRF). When probing the ionosphere at the carrier frequencies of the EISCAT Incoherent Scatter Radar facilities, the range extent of the detectable target is typically of the order of one thousand kilometers - about seven milliseconds - whereas the characteristic correlation time of the scattered signal varies from a few milliseconds in the D-region to only tens of microseconds in the F-region. If one is interested in estimating the scattering autocorrelation function (ACF) at time lags shorter than the F-region correlation time, the D-region must be considered as a moderately overspread target, whereas the F-region is a severely overspread one. Given the technical restrictions of the radar hardware, a combination of ATC and phase-coded long pulses is advantageous for this kind of target. We evaluate such an experiment under infinitely low signal-to-noise ratio (SNR) conditions using lag profile inversion. In addition, a qualitative evaluation under high-SNR conditions is performed by analysing simulated data. The results show that an acceptable estimation accuracy and a very good lag resolution in the D-region can be achieved with a pulse length long enough for simultaneous E- and F-region measurements with a reasonable lag extent. The new experiment design is tested with the EISCAT Tromsø VHF (224 MHz) radar. An example of a full D/E/F-region ACF from the test run is shown at the end of the paper.

  6. FAA Smoke Transport Code

    Energy Science and Technology Software Center (ESTSC)

    2006-10-27

    FAA Smoke Transport Code, a physics-based Computational Fluid Dynamics tool, which couples heat, mass, and momentum transfer, has been developed to provide information on smoke transport in cargo compartments with various geometries and flight conditions. The software package contains a graphical user interface for specification of geometry and boundary conditions, analysis module for solving the governing equations, and a post-processing tool. The current code was produced by making substantial improvements and additions to a codemore » obtained from a university. The original code was able to compute steady, uniform, isothermal turbulent pressurization. In addition, a preprocessor and postprocessor were added to arrive at the current software package.« less

  7. Seals Code Development Workshop

    NASA Technical Reports Server (NTRS)

    Hendricks, Robert C. (Compiler); Liang, Anita D. (Compiler)

    1996-01-01

    Seals Workshop of 1995 industrial code (INDSEAL) release include ICYL, GCYLT, IFACE, GFACE, SPIRALG, SPIRALI, DYSEAL, and KTK. The scientific code (SCISEAL) release includes conjugate heat transfer and multidomain with rotordynamic capability. Several seals and bearings codes (e.g., HYDROFLEX, HYDROTRAN, HYDROB3D, FLOWCON1, FLOWCON2) are presented and results compared. Current computational and experimental emphasis includes multiple connected cavity flows with goals of reducing parasitic losses and gas ingestion. Labyrinth seals continue to play a significant role in sealing with face, honeycomb, and new sealing concepts under investigation for advanced engine concepts in view of strict environmental constraints. The clean sheet approach to engine design is advocated with program directions and anticipated percentage SFC reductions cited. Future activities center on engine applications with coupled seal/power/secondary flow streams.

  8. Code query by example

    NASA Astrophysics Data System (ADS)

    Vaucouleur, Sebastien

    2011-02-01

    We introduce code query by example for customisation of evolvable software products in general and of enterprise resource planning systems (ERPs) in particular. The concept is based on an initial empirical study on practices around ERP systems. We motivate our design choices based on those empirical results, and we show how the proposed solution helps with respect to the infamous upgrade problem: the conflict between the need for customisation and the need for upgrade of ERP systems. We further show how code query by example can be used as a form of lightweight static analysis, to detect automatically potential defects in large software products. Code query by example as a form of lightweight static analysis is particularly interesting in the context of ERP systems: it is often the case that programmers working in this field are not computer science specialists but more of domain experts. Hence, they require a simple language to express custom rules.

  9. Code inspection instructional validation

    NASA Technical Reports Server (NTRS)

    Orr, Kay; Stancil, Shirley

    1992-01-01

    The Shuttle Data Systems Branch (SDSB) of the Flight Data Systems Division (FDSD) at Johnson Space Center contracted with Southwest Research Institute (SwRI) to validate the effectiveness of an interactive video course on the code inspection process. The purpose of this project was to determine if this course could be effective for teaching NASA analysts the process of code inspection. In addition, NASA was interested in the effectiveness of this unique type of instruction (Digital Video Interactive), for providing training on software processes. This study found the Carnegie Mellon course, 'A Cure for the Common Code', effective for teaching the process of code inspection. In addition, analysts prefer learning with this method of instruction, or this method in combination with other methods. As is, the course is definitely better than no course at all; however, findings indicate changes are needed. Following are conclusions of this study. (1) The course is instructionally effective. (2) The simulation has a positive effect on student's confidence in his ability to apply new knowledge. (3) Analysts like the course and prefer this method of training, or this method in combination with current methods of training in code inspection, over the way training is currently being conducted. (4) Analysts responded favorably to information presented through scenarios incorporating full motion video. (5) Some course content needs to be changed. (6) Some content needs to be added to the course. SwRI believes this study indicates interactive video instruction combined with simulation is effective for teaching software processes. Based on the conclusions of this study, SwRI has outlined seven options for NASA to consider. SwRI recommends the option which involves creation of new source code and data files, but uses much of the existing content and design from the current course. Although this option involves a significant software development effort, SwRI believes this option

  10. Aeroacoustic Prediction Codes

    NASA Technical Reports Server (NTRS)

    Gliebe, P; Mani, R.; Shin, H.; Mitchell, B.; Ashford, G.; Salamah, S.; Connell, S.; Huff, Dennis (Technical Monitor)

    2000-01-01

    This report describes work performed on Contract NAS3-27720AoI 13 as part of the NASA Advanced Subsonic Transport (AST) Noise Reduction Technology effort. Computer codes were developed to provide quantitative prediction, design, and analysis capability for several aircraft engine noise sources. The objective was to provide improved, physics-based tools for exploration of noise-reduction concepts and understanding of experimental results. Methods and codes focused on fan broadband and 'buzz saw' noise and on low-emissions combustor noise and compliment work done by other contractors under the NASA AST program to develop methods and codes for fan harmonic tone noise and jet noise. The methods and codes developed and reported herein employ a wide range of approaches, from the strictly empirical to the completely computational, with some being semiempirical analytical, and/or analytical/computational. Emphasis was on capturing the essential physics while still considering method or code utility as a practical design and analysis tool for everyday engineering use. Codes and prediction models were developed for: (1) an improved empirical correlation model for fan rotor exit flow mean and turbulence properties, for use in predicting broadband noise generated by rotor exit flow turbulence interaction with downstream stator vanes: (2) fan broadband noise models for rotor and stator/turbulence interaction sources including 3D effects, noncompact-source effects. directivity modeling, and extensions to the rotor supersonic tip-speed regime; (3) fan multiple-pure-tone in-duct sound pressure prediction methodology based on computational fluid dynamics (CFD) analysis; and (4) low-emissions combustor prediction methodology and computer code based on CFD and actuator disk theory. In addition. the relative importance of dipole and quadrupole source mechanisms was studied using direct CFD source computation for a simple cascadeigust interaction problem, and an empirical combustor

  11. Securing mobile code.

    SciTech Connect

    Link, Hamilton E.; Schroeppel, Richard Crabtree; Neumann, William Douglas; Campbell, Philip LaRoche; Beaver, Cheryl Lynn; Pierson, Lyndon George; Anderson, William Erik

    2004-10-01

    If software is designed so that the software can issue functions that will move that software from one computing platform to another, then the software is said to be 'mobile'. There are two general areas of security problems associated with mobile code. The 'secure host' problem involves protecting the host from malicious mobile code. The 'secure mobile code' problem, on the other hand, involves protecting the code from malicious hosts. This report focuses on the latter problem. We have found three distinct camps of opinions regarding how to secure mobile code. There are those who believe special distributed hardware is necessary, those who believe special distributed software is necessary, and those who believe neither is necessary. We examine all three camps, with a focus on the third. In the distributed software camp we examine some commonly proposed techniques including Java, D'Agents and Flask. For the specialized hardware camp, we propose a cryptographic technique for 'tamper-proofing' code over a large portion of the software/hardware life cycle by careful modification of current architectures. This method culminates by decrypting/authenticating each instruction within a physically protected CPU, thereby protecting against subversion by malicious code. Our main focus is on the camp that believes that neither specialized software nor hardware is necessary. We concentrate on methods of code obfuscation to render an entire program or a data segment on which a program depends incomprehensible. The hope is to prevent or at least slow down reverse engineering efforts and to prevent goal-oriented attacks on the software and execution. The field of obfuscation is still in a state of development with the central problem being the lack of a basis for evaluating the protection schemes. We give a brief introduction to some of the main ideas in the field, followed by an in depth analysis of a technique called 'white-boxing'. We put forth some new attacks and improvements

  12. Brain creatine depletion: guanidinoacetate methyltransferase deficiency (improving with creatine supplementation).

    PubMed

    Leuzzi, V; Bianchi, M C; Tosetti, M; Carducci, C; Cerquiglini, C A; Cioni, G; Antonozzi, I

    2000-11-14

    The authors describe an Italian child with guanidinoacetate methyltransferase deficiency, neurologic regression, movement disorders, and epilepsy during the first year of life. Brain MRI showed pallidal and periaqueductal alterations. In vivo 1H-MRS showed brain creatine depletion. The assessment of guanidinoacetic acid concentration in biologic fluids confirmed the diagnosis. Clinical, biochemical, and neuroradiologic improvement followed creatine supplementation. PMID:11087795

  13. Identifying water mass depletion in northern Iraq observed by GRACE

    NASA Astrophysics Data System (ADS)

    Mulder, G.; Olsthoorn, T. N.; Al-Manmi, D. A. M. A.; Schrama, E. J. O.; Smidt, E. H.

    2015-03-01

    Observations acquired by Gravity Recovery And Climate Experiment (GRACE) mission indicate a mass loss of 146 ± 6 mm equivalent water height (EWH) in northern Iraq between 2007 and 2009. These data are used as an independent validation of lake mass variations and a rainfall-runoff model, which is based on local geology and climate conditions. Model inputs are precipitation from Tropical Rainfall Measurement Mission (TRMM) observations, and climatic parameters from Global Land Data Assimilation Systems (GLDAS) model parameters. The model is calibrated with observed river discharge and includes a representation of the karstified aquifers in the region to improve model realism. Lake mass variations were derived from Moderate Resolution Imaging Spectroradiometer (MODIS) in combination with satellite altimetry and some in situ data. Our rainfall-runoff model confirms that northern Iraq suffered a drought between 2007 and 2009 and captures the annual cycle and longer trend of the observed GRACE data. The total mass depletion seen by GRACE between 2007 and 2009 is mainly explained by a lake mass depletion of 75 ± 3 mm EWH and a natural groundwater depletion of 39 ± 8 mm EWH. Our findings indicate that anthropogenic groundwater extraction has a minor influence in this region, while a decline in lake mass and natural depletion of groundwater play a key role.

  14. DURABILITY OF DEPLETED URANIUM AGGREGATES (DUAGG) IN DUCRETE SHIELDING APPLICATIONS

    SciTech Connect

    Mattus, Catherine H.; Dole, Leslie R.

    2003-02-27

    The depleted uranium (DU) inventory in the United States exceeds 500,000 metric tonnes. To evaluate the possibilities for reuse of this stockpile of DU, the U.S. Department of Energy (DOE) has created a research and development program to address the disposition of its DU(1). One potential use for this stockpile material is in the fabrication of nuclear shielding casks for the storage, transport, and disposal of spent nuclear fuels. The use of the DU-based shielding would reduce the size and weight of the casks while allowing a level of protection from neutrons and gamma rays comparable to that afforded by steel and concrete. DUAGG (depleted uranium aggregate) is formed of depleted uranium dioxide (DUO2) sintered with a synthetic-basalt-based binder. This study was designed to investigate possible deleterious reactions that could occur between the cement paste and the DUAGG. After 13 months of exposure to a cement pore solution, no deleterious expansive mineral phases were observed to form either with the DUO2 or with the simulated-basalt sintering phases. In the early stages of these exposure tests, Oak Ridge National Laboratory preliminary results confirm that the surface reactions of this aggregate proceed more slowly than expected. This finding may indicate that DUAGG/DUCRETE (depleted uranium concrete) casks could have service lives sufficient to meet the projected needs of DOE and the commercial nuclear power industry.

  15. Fully depleted, thick, monolithic CMOS pixels with high quantum efficiency

    NASA Astrophysics Data System (ADS)

    Clarke, A.; Stefanov, K.; Johnston, N.; Holland, A.

    2015-04-01

    The Centre for Electronic Imaging (CEI) has an active programme of evaluating and designing Complementary Metal-Oxide Semiconductor (CMOS) image sensors with high quantum efficiency, for applications in near-infrared and X-ray photon detection. This paper describes the performance characterisation of CMOS devices made on a high resistivity 50 μ m thick p-type substrate with a particular focus on determining the depletion depth and the quantum efficiency. The test devices contain 8 × 8 pixel arrays using CCD-style charge collection, which are manufactured in a low voltage CMOS process by ESPROS Photonics Corporation (EPC). Measurements include determining under which operating conditions the devices become fully depleted. By projecting a spot using a microscope optic and a LED and biasing the devices over a range of voltages, the depletion depth will change, causing the amount of charge collected in the projected spot to change. We determine if the device is fully depleted by measuring the signal collected from the projected spot. The analysis of spot size and shape is still under development.

  16. Seasonal oxygen depletion in the North Sea, a review.

    PubMed

    Topcu, H D; Brockmann, U H

    2015-10-15

    Seasonal mean oxygen depletion in offshore and coastal North Sea bottom waters was shown to range between 0.9 and 1.8 mg/L, corresponding to 95-83% saturation, between July and October over a 30-year assessment period (1980-2010). The magnitude of oxygen depletion was controlled by thermal stratification, modulated by water depth and nitrogen availability. Analyses were based on about 19,000 combined data sets. Eutrophication problem areas were identified mainly in coastal waters by oxygen minima, the lower 10th percentile of oxygen concentrations, and deviations of oxygen depletion from correlated stratification values. Connections between oxygen consumption and nitrogen sources and conversion, including denitrification, were indicated by correlations. Mean oxygen consumption reflected a minimum seasonal turnover of 3.1 g N/m(2) in the south-eastern North Sea, including denitrification of 1 g N/m(2). Oxygen depletion was underestimated in shallow coastal waters due to repeated erosion of stratification as indicated by local high variability. PMID:26234616

  17. Initial PVO evidence of electron depletion signatures downstream of Venus

    NASA Technical Reports Server (NTRS)

    Intriligator, D. S.; Hartle, R. E.; Perez-De-tejada, H.; Siscoe, G. L.

    1993-01-01

    This first analysis of Pioneer Venus Orbiter (PVO) plasma analyzer electron measurements obtained in early 1992 during teh PVO entry phase of the mission indicates the presence downstream from the terminator of a depletion or 'bite out' of energetic ionosheath electrons similar to that observed on Mariner 10. There is more than one possible explanation for this energetic electron depletion. If it is due to atmospheric scattering, the electrons traveling along draped magnetic flux tubes that thread through the Venus neutral atmosphere would lose energy from impact ionization with oxygen. The cross-section for such electron impact ionization of oxygen has a peak near 100 eV, and it remains high above this energy, so atmospheric loss could provde a natural process for electrons at these energies to be selectively removed. In this case, our results are consistent with the Kar et al. (1994) study of PVO atmospheric entry ion mass spectrometer data, which indicates that electron impact plays a significant role in maintaining the nightside ionosphere. Although it is appealing to interpret the energetic electron depletion in terms of direct atmospheric scattering, alternatively it could result from strong draping which connects the depletion region magnetically to the weak downstream bow shock and thereby reduces the electron source strength.

  18. Initial PVO Evidence of Electron Depletion Signatures Downstream of Venus

    NASA Technical Reports Server (NTRS)

    Intriligator, D. S.; Hartle, R. E.; Perez-de-Tejada, H.; Siscoe, G. L.

    1993-01-01

    This first analysis of Pioneer Venus Orbiter (PVO) plasma analyzer electron measurements obtained in early 1992 during the PVO entry phase of the mission indicates the presence downstream from the terminator of a depletion or "bite out" of energetic ionosheath electrons similar to that observed on Mariner 10. There is more than one possible explanation for this energetic electron depletion. If it is due to atmospheric scattering, the electrons traveling along draped magnetic flux tubes that thread through the Venus neutral atmosphere would lose energy from impact ionization with oxygen. The cross-section for such electron impact ionization of oxygen has a peak near 100 eV, and it remains high above this energy, so atmospheric loss could provide a natural process for electrons at these energies to be selectively removed. In this case, our results are consistent with the Kar et al. (1994) study of PVO atmospheric entry ion mass spectrometer data which indicates that electron impact plays a significant role in maintaining the nightside ionosphere. Although it is appealing to interpret the energetic electron depletion in terms of direct atmospheric scattering, alternatively it could result from strong draping which connects the depletion region magnetically to the weak downstream bow shock and thereby reduces the electron source strength.

  19. Depletion studies of two contrasting D-2 reefs

    SciTech Connect

    Gillund, G.N.; Patel, C.

    1980-01-01

    The Nisku B and G pools are 2 W. Pembina D-2 pools with contrasting reservoir properties. Average porosity, permeability, and maximum thickness are 5%, 130 md, and 95 m; and 16.4%, 7100 md and 19 m, respectively. The results of the depletion model studies of waterflooding and miscible flooding and some of the problems that occurred during these studies are reviewed.

  20. Abrupt Depletion Layer Approximation for the Metal Insulator Semiconductor Diode.

    ERIC Educational Resources Information Center

    Jones, Kenneth

    1979-01-01

    Determines the excess surface change carrier density, surface potential, and relative capacitance of a metal insulator semiconductor diode as a function of the gate voltage, using the precise questions and the equations derived with the abrupt depletion layer approximation. (Author/GA)

  1. Theory of colloid depletion stabilization by unattached and adsorbed polymers.

    PubMed

    Semenov, A N; Shvets, A A

    2015-12-01

    The polymer-induced forces between colloidal particles in a semidilute or concentrated polymer solution are considered theoretically. This study is focussed on the case of partially adsorbing colloidal surfaces involving some attractive centers able to trap polymer segments. In the presence of free polymers the particles are covered by self-assembled fluffy layers whose structure is elucidated. It is shown that the free-polymer-induced interaction between the particles is repulsive at distances exceeding the polymer correlation length, and that this depletion repulsion can be strongly enhanced due to the presence of fluffy layers. This enhanced depletion stabilization mechanism (which works in tandem with a more short-range steric repulsion of fluffy layers) can serve on its own to stabilize colloidal dispersions. More generally, we identify three main polymer-induced interaction mechanisms: depletion repulsion, depletion attraction, and steric repulsion. Their competition is analyzed both numerically and analytically based on an asymptotically rigorous mean-field theory. It is shown that colloid stabilization can be achieved by simply increasing the molecular weight of polymer additives, or by changing their concentration. PMID:26400677

  2. Spearfishing to depletion: evidence from temperate reef fishes in Chile.

    PubMed

    Godoy, Natalio; Gelcich, L Stefan; Vásquez, Julio A; Castilla, Juan Carlos

    2010-09-01

    Unreliable and data-poor marine fishery landings can lead to a lack of regulatory action in fisheries management. Here we use official Chilean landing reports and non-conventional indicators, such as fishers' perceptions and spearfishing competition results, to provide evidence of reef fishes depletions caused by unregulated spearfishing. Results show that the three largest and most emblematic reef fishes targeted mainly by spearfishers (> 98% of landings) [Graus nigra (vieja negra), Semicossyphus darwini (sheephead or pejeperro), and Medialuna ancietae (acha)] show signs of depletion in terms of abundance and size and that overall the catches of reef fishes have shifted from large carnivore species toward smaller-sized omnivore and herbivore species. Information from two snorkeling speargun world championships (1971 and 2004, Iquique, Chile) and from fishers' perceptions shows the mean size of reef fish to be declining. Although the ecological consequences of reef fish depletion are not fully understood in Chile, evidence of spearfishing depleting temperate reef fishes must be explicitly included in policy debates. This would involve bans or strong restrictions on the use of SCUBA and hookah diving gear for spearfishing, and minimum size limits. It may also involve academic and policy discussions regarding conservation and fisheries management synergies within networks of no-take and territorial user-rights fisheries areas, as a strategy for the sustainable management of temperate and tropical reef fisheries. PMID:20945755

  3. Computation of rate and volume of stream depletion by wells

    USGS Publications Warehouse

    Jenkins, C.T.

    1968-01-01

    When field conditions approach certain assumed conditions, the depletion in flow of a nearby stream caused by pumping a well can be calculated readily by using dimensionless curves and tables. Computations can be made of (1) the rate of stream depletion at any time during the pumping period or the following nonpumping period, (2) the volume of water induced from the stream during any period, pumping or non-pumping, and (3) the effects, both in rate and volume of stream depletion, of any selected pattern of intermittent pumping. Sample computations illustrate the use of the curves and tables. An example shows that intermittent pumping may have a pattern of stream depletion not greatly different from a pattern for steady pumping of an equal volume. The residual effects of pumping, that is, effects after pumping stops, on streamflow may often be greater than the effects during the pumping period. Adequate advance planning that includes consideration of residual effects thus is essential to effective management of a stream-aquifer system.

  4. 9. VIEW OF FOUNDRY FURNACE, DEPLETED URANIUM INGOTS, BERYLLIUM INGOTS, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW OF FOUNDRY FURNACE, DEPLETED URANIUM INGOTS, BERYLLIUM INGOTS, AND ALUMINUM SHAPES WERE PRODUCED IN THE FOUNDRY. (10/30/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  5. Decaying equatorial F region plasma depletions

    NASA Astrophysics Data System (ADS)

    Hysell, D. L.; Kelley, M. C.

    1997-09-01

    We analyze plasma density data from the AE-E satellite to determine how F region irregularities decay. This satellite had a low inclination orbit that was ultimately circular at an altitude of 434 km. It frequently observed plasma depletions in the postsunset regime during spread F conditions, sometimes along a trajectory affording a ``horizontal cut'' perspective through the field-aligned irregularities. On one occasion, the satellite passed through nearly the same region of depleted flux tubes on sequential orbits. Data from these orbits imply that the irregularities decay at a constant rate over a broad range of horizontal scale sizes. We introduce a statistical model of the intermediate-scale (10 km-100 m) plasma irregularities and use it to infer a value for the perpendicular ambipolar diffusion coefficient from the measured decay rate. The value we estimate (2m2/s) is close to the expected classical value. The uniform decay rate and the quasi-universal nature of the intermediate-scale spectra hint that the irregularities themselves maintain a characteristic shape as they decay. High-resolution satellite density measurements show that irregularities have the form of kilometer-scale quasi-periodic depletions. We propose a one-dimensional, nonlinear model of the collisional interchange instability which admits a closed-form, steady state solution predicting the shape of the depletions. Computer simulations of the model produce kilometer-scale waves that resemble the in situ observations.

  6. Stored mafic/ultramafic crust and early Archean mantle depletion

    NASA Technical Reports Server (NTRS)

    Chase, Clement G.; Patchett, P. J.

    1990-01-01

    Both early and late Archean rocks from greenstone belts and felsic gneiss complexes exhibit positive epsilon(Nd) values of +1 to +5 by 3.5 Ga, demonstrating that a depleted mantle reservoir existed very early. The amount of preserved pre-3.0 Ga continental crust cannot explain such high epsilon values in the depleted residue unless the volume of residual mantle was very small: a layer less than 70 km thick by 3.0 Ga. Repeated and exclusive sampling of such a thin layer, especially in forming the felsic gneiss complexes, is implausible. Extraction of enough continental crust to deplete the early mantle and its destructive recycling before 3.0 Ga ago requires another implausibility, that the sites of crustal generation of recycling were substantially distinct. In contrast, formation of mafic or ultramafic crust analogous to present-day oceanic crust was continuous from very early times. Recycled subducted oceanic lithosphere is a likely contributor to present-day hotspot magmas, and forms a reservoir at least comparable in volume to continental crust. Subduction of an early mafic/ultramafic oceanic crust and temporary storage rather than immediate mixing back into undifferentiated mantle may be responsible for the depletion and high epsilon(Nd) values of the Archean upper mantle.

  7. Depleting methyl bromide residues in soil by reaction with bases

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Despite generally being considered the most effective soil fumigant, methyl bromide (MeBr) use is being phased out because its emissions from soil can lead to stratospheric ozone depletion. However, a large amount is still currently used due to Critical Use Exemptions. As strategies for reducing the...

  8. Depletion of penicillin G residues in sows after intramuscular injection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A penicillin G procaine residue depletion study was conducted in heavy sows to estimate the pre-slaughter withdrawal periods necessary to clear penicillin from kidney and muscle. Heavy sows (n = 126) were treated with penicillin G procaine at a 5x dose (33,000 IU/kg) for 3 consecutive days by intra...

  9. EFFECTS OF STRATOSPHERE OZONE DEPLETION ON AQUATIC ORGANISMS

    EPA Science Inventory

    As a result of stratospheric ozone depletion, UV-Bradiation (290-320 nm) leaching aquatic environments is likely to increase over the next few decades. vailable information suggests that UV-B radiation can have a variety of deleterious effects on marine and freshwater ecosystems....

  10. A method to estimate groundwater depletion from confining layers

    USGS Publications Warehouse

    Konikow, L.F.; Neuzil, C.E.

    2007-01-01

    Although depletion of storage in low-permeability confining layers is the source of much of the groundwater produced from many confined aquifer systems, it is all too frequently overlooked or ignored. This makes effective management of groundwater resources difficult by masking how much water has been derived from storage and, in some cases, the total amount of water that has been extracted from an aquifer system. Analyzing confining layer storage is viewed as troublesome because of the additional computational burden and because the hydraulic properties of confining layers are poorly known. In this paper we propose a simplified method for computing estimates of confining layer depletion, as well as procedures for approximating confining layer hydraulic conductivity (K) and specific storage (Ss) using geologic information. The latter makes the technique useful in developing countries and other settings where minimal data are available or when scoping calculations are needed. As such, our approach may be helpful for estimating the global transfer of groundwater to surface water. A test of the method on a synthetic system suggests that the computational errors will generally be small. Larger errors will probably result from inaccuracy in confining layer property estimates, but these may be no greater than errors in more sophisticated analyses. The technique is demonstrated by application to two aquifer systems: the Dakota artesian aquifer system in South Dakota and the coastal plain aquifer system in Virginia. In both cases, depletion from confining layers was substantially larger than depletion from the aquifers.

  11. 11. VIEW OF DEPLETED URANIUM INGOT. THE METALS WERE PLACED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW OF DEPLETED URANIUM INGOT. THE METALS WERE PLACED IN CRUCIBLES, LOADED INTO ONE OF EIGHT INDUCTION FURNACES AND MELTED IN A VACUUM ATMOSPHERE. (11/11/57) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  12. Identifying water mass depletion in Northern Iraq observed by GRACE

    NASA Astrophysics Data System (ADS)

    Mulder, G.; Olsthoorn, T. N.; Al-Manmi, D. A. M. A.; Schrama, E. J. O.; Smidt, E. H.

    2014-10-01

    Observations acquired by Gravity Recovery And Climate Experiment (GRACE) mission indicate a mass loss of 31 ± 3 km3 or 130 ± 14 mm in Northern Iraq between 2007 and 2009. This data is used as an independent validation of a hydrologic model of the region including lake mass variations. We developed a rainfall-runoff model for five tributaries of the Tigris River, based on local geology and climate conditions. Model inputs are precipitation from Tropical Rainfall Measurement Mission (TRMM) observations, and potential evaporation from GLDAS model parameters. Our model includes a representation of the karstified aquifers that cause large natural groundwater variations in this region. Observed river discharges were used to calibrate our model. In order to get the total mass variations, we corrected for lake mass variations derived from Moderate Resolution Imaging Spectroradiometer (MODIS) in combination with satellite altimetry and some in-situ data. Our rainfall-runoff model confirms that Northern Iraq suffered a drought between 2007 and 2009 and is consistent with the mass loss observed by GRACE over that period. Also, GRACE observed the annual cycle predicted by the rainfall-runoff model. The total mass depletion seen by GRACE between 2007 and 2009 is mainly explained by a lake mass depletion of 74 ± 4 mm and a natural groundwater depletion of 37 ± 6 mm. Our findings indicate that man-made groundwater extraction has a minor influence in this region while depletion of lake mass and geology play a key role.

  13. Fully depleted back-illuminated p-channel CCD development

    SciTech Connect

    Bebek, Chris J.; Bercovitz, John H.; Groom, Donald E.; Holland, Stephen E.; Kadel, Richard W.; Karcher, Armin; Kolbe, William F.; Oluseyi, Hakeem M.; Palaio, Nicholas P.; Prasad, Val; Turko, Bojan T.; Wang, Guobin

    2003-07-08

    An overview of CCD development efforts at Lawrence Berkeley National Laboratory is presented. Operation of fully-depleted, back-illuminated CCD's fabricated on high resistivity silicon is described, along with results on the use of such CCD's at ground-based observatories. Radiation damage and point-spread function measurements are described, as well as discussion of CCD fabrication technologies.

  14. Ozone depletion, related UVB changes and increased skin cancer incidence

    NASA Astrophysics Data System (ADS)

    Kane, R. P.

    1998-03-01

    Stratospheric ozone at middle latitudes shows a seasonal variation of about +/-20%, a quasi-biennial oscillation of 1-10% range and a long-term variation in which the level was almost steady up to about 1979 and declined thereafter to the present day by about 10%. These variations are expected to be reflected in solar UVB observed at the ground, but in an opposite direction. Thus UVB should have had a long-term increase of about 10-20%, which should cause an increase in skin cancer incidence of about 20-40%. Skin cancer incidence has increased all over the world, e.g. about 90% in USA during 1974-1990. It is popularly believed that this increase in skin cancer incidence is related to the recent ozone depletion. This seems to be incorrect, for two reasons. Firstly, the observed skin cancer increase is too large (90%) compared with the expected value (40%) from ozone depletion. Secondly, cancer does not develop immediately after exposure to solar UVB. The sunburns may occur within hours; but cancer development and detection may take years, even decades. Hence the observed skin cancer increase since 1974 (no data available for earlier periods) must have occurred due to exposure to solar UVB in the 1950s and 1960s, when there was no ozone depletion. Thus, the skin cancer increase must be attributed to harmful solar UVB levels existing even in the 1960s, accentuated later not by ozone depletion (which started only much later, by 1979) but by other causes, such as a longer human life span, better screening, increasing tendencies of sunbathing at beaches, etc., in affluent societies. On the other hand, the recent ozone depletion and the associated UVB increases will certainly take their toll; only that the effects will not be noticed now but years or decades from now. The concern for the future expressed in the Montreal Protocol for reducing ozone depletion by controlling CFC production is certainly justified, especially because increased UVB is harmful to animal and

  15. Global Storm-Time Depletion of the Outer Electron Belt

    NASA Astrophysics Data System (ADS)

    Ukhorskiy, A. Y.; Sitnov, M. I.; Millan, R. M.; Kress, B. T.; Fennell, J. F.

    2014-12-01

    The outer radiation belt consists of relativistic (≳0.5 MeV) electrons trapped on closed trajectories around Earth where its magnetic field is nearly dipolar. During increased geomagnetic activity electron intensities in the belt can vary by orders of magnitude at different spatial and temporal scale. The main phase of geomagnetic storms often produces deep depletions of electron intensities over broad regions of the outer belt. Previous studies identified three possible processes that can contribute to the depletions: fully adiabatic inflation of electron drift orbits caused the ring current growth, electron loss into the atmosphere due to pitch-angle scattering by plasma waves (e.g., EMIC and whistler waves), and electron escape through the magnetopause boundary. In this paper we investigate the relative importance of the magnetopause losses to the rapid depletion of the outer belt observed at the Van Allen Probes spacecraft during the main phase of March 17, 2013 storm. The intensities of > 1 MeV electrons were depleted by more that an order of magnitude over the entire radial extent of the belt in less than 6 hours after the sudden storm commencement. For the analysis we used three-dimensional test-particle simulations of global evolution of the outer belt in the Tsyganenko-Sitnov (TS07D) magnetic field model with the inductive electric field. The comparison of the simulation results with electron measurements from the MagEIS experiment shows that the magnetopause losses in the model accounts for most of the observed depletion. The individual electron motion the process is non-adiabatic; the third invariant is violated by global variations of the inner magnetospheric fields caused by the magnetopause compressions and the buildup of ring current, while the second invariant is violated at drift orbit bifurcations. The analysis shows that the observed deep depletion of radiation belt intensities is enabled by the change in the global configuration of magnetic

  16. Mercury depletion events over Antarctic and Arctic oceans

    NASA Astrophysics Data System (ADS)

    Nerentorp Mastromonaco, M. G.; Gardfeldt, K.; Wangberg, I.; Jourdain, B.; Dommergue, A.; Kuronen, P.; Pirrone, N.; Jacobi, H.

    2013-12-01

    Mercury is a global pollutant and in its elemental form it is spread by air to remote areas far away from point sources. In Antarctic and Arctic regions the airborne mercury may be oxidized, followed by deposition of the metal on land and sea surfaces. It is previously known that during early spring in these regions, processes involving halogen radical photochemistry induce an oxidation of gaseous elemental mercury (GEM) in air. This phenomenon is known as an atmospheric mercury depletion event (AMDE) and is characterized by sudden and remarkable decreases in GEM that occurs within hours or days. All or most part of the GEM in air is transformed into gaseous oxidized mercury (GOM) and particulate mercury (HgP). Equivalent ozone depletion events (ODE) do also occur in Antarctic and Arctic regions and the halogen radical photolytic processes involved for AMDEs and ODEs are interrelated. During two oceanographic campaigns at the Weddell Sea onboard RV Polarstern, ANTXXIX/6 (130608-130812) and ANTXXIX/7 (130814-131016), continuous measurements of GEM, GOM and HgP in air were performed using the Tekran mercury speciation system 1130/35. This is the first time such long time series of GEM-, GOM- and HgP data has been achieved over water in the Antarctic during winter and spring. Several mercury depletion events were detected as early as in the middle of July and are correlated and verified with ozone measurements onboard the ship. The observed depletion events were characterised by sudden major decreases in both GEM and ozone concentrations and highly elevated values of HgP. A depletion event is a local phenomenon but evidences show that traces of such events can be detected far away from its origin. During a spring campaign at the Pallas-Matorova station in northern Finland (68o00'N, 24o14'E), GEM, GOM and HgP were measured during three weeks in April 2012 using the Tekran mercury speciation system 1130/35. Traces of remote AMDEs were observed by sudden decreases of GEM

  17. Calcium depletion in a Southeastern United States forest ecosystem

    USGS Publications Warehouse

    Huntington, T.G.; Hooper, R.P.; Johnson, C.E.; Aulenbach, Brent T.; Cappellato, R.; Blum, A.E.

    2000-01-01

    Forest soil Ca depletion through leaching and vegetation uptake may threaten long-term sustainability of forest productivity in the southeastern USA. This study was conducted to assess Ca pools and fluxes in a representative southern Piedmont forest to determine the soil Ca depletion rate. Soil Ca storage, Ca inputs in atmospheric deposition, and outputs in soil leaching and vegetation uptake were investigated at the Panola Mountain Research Watershed (PMRW) near Atlanta, GA. Average annual outputs of 12.3 kg ha-1 yr-1 in uptake into merchantable wood and 2.71 kg ha-1 yr-1 soil leaching exceeded inputs in atmospheric deposition of 2.24 kg ha-1 yr-1. The annual rate of Ca uptake into merchantable wood exceeds soil leaching losses by a factor of more than five. The potential for primary mineral weathering to provide a substantial amount of Ca inputs is low. Estimates of Ca replenishment through mineral weathering in the surface 1 m of soil and saprolite was estimated to be 0.12 kg ha-1 yr-1. The weathering rate in saprolite and partially weathered bedrock below the surface 1 m is similarly quite low because mineral Ca is largely depleted. The soil Ca depletion rate at PMRW is estimated to be 12.7 kg ha-1 yr-1. At PMRW and similar hardwood-dominated forests in the Piedmont physiographic province, Ca depletion will probably reduce soil reserves to less than the requirement for a merchantable forest stand in ???80 yr. This assessment and comparable analyses at other southeastern USA forest sites suggests that there is a strong potential for a regional problem in forest nutrition in the long term.Forest soil Ca depletion through leaching and vegetation uptake may threaten long-term sustainability of forest productivity in the southeastern USA. This study was conducted to assess Ca pools and fluxes in a representative southern Piedmont forest to determine the soil Ca depletion rate. Soil Ca storage, Ca inputs in atmospheric deposition, and outputs in soil leaching and

  18. Mechanistic and Kinetic Differences between Reverse Transcriptases of Vpx Coding and Non-coding Lentiviruses*

    PubMed Central

    Lenzi, Gina M.; Domaoal, Robert A.; Kim, Dong-Hyun; Schinazi, Raymond F.; Kim, Baek

    2015-01-01

    Among lentiviruses, HIV Type 2 (HIV-2) and many simian immunodeficiency virus (SIV) strains replicate rapidly in non-dividing macrophages, whereas HIV Type 1 (HIV-1) replication in this cell type is kinetically delayed. The efficient replication capability of HIV-2/SIV in non-dividing cells is induced by a unique, virally encoded accessory protein, Vpx, which proteasomally degrades the host antiviral restriction factor, SAM domain- and HD domain-containing protein 1 (SAMHD1). SAMHD1 is a dNTPase and kinetically suppresses the reverse transcription step of HIV-1 in macrophages by hydrolyzing and depleting cellular dNTPs. In contrast, Vpx, which is encoded by HIV-2/SIV, kinetically accelerates reverse transcription by counteracting SAMHD1 and then elevating cellular dNTP concentration in non-dividing cells. Here, we conducted the pre-steady-state kinetic analysis of reverse transcriptases (RTs) from two Vpx non-coding and two Vpx coding lentiviruses. At all three sites of the template tested, the two RTs of the Vpx non-coding viruses (HIV-1) displayed higher kpol values than the RTs of the Vpx coding HIV-2/SIV, whereas there was no significant difference in the Kd values of these two groups of RTs. When we employed viral RNA templates that induce RT pausing by their secondary structures, the HIV-1 RTs showed more efficient DNA synthesis through pause sites than the HIV-2/SIV RTs, particularly at low dNTP concentrations found in macrophages. This kinetic study suggests that RTs of the Vpx non-coding HIV-1 may have evolved to execute a faster kpol step, which includes the conformational changes and incorporation chemistry, to counteract the limited dNTP concentration found in non-dividing cells and still promote efficient viral reverse transcription. PMID:26483545

  19. Mechanistic and Kinetic Differences between Reverse Transcriptases of Vpx Coding and Non-coding Lentiviruses.

    PubMed

    Lenzi, Gina M; Domaoal, Robert A; Kim, Dong-Hyun; Schinazi, Raymond F; Kim, Baek

    2015-12-11

    Among lentiviruses, HIV Type 2 (HIV-2) and many simian immunodeficiency virus (SIV) strains replicate rapidly in non-dividing macrophages, whereas HIV Type 1 (HIV-1) replication in this cell type is kinetically delayed. The efficient replication capability of HIV-2/SIV in non-dividing cells is induced by a unique, virally encoded accessory protein, Vpx, which proteasomally degrades the host antiviral restriction factor, SAM domain- and HD domain-containing protein 1 (SAMHD1). SAMHD1 is a dNTPase and kinetically suppresses the reverse transcription step of HIV-1 in macrophages by hydrolyzing and depleting cellular dNTPs. In contrast, Vpx, which is encoded by HIV-2/SIV, kinetically accelerates reverse transcription by counteracting SAMHD1 and then elevating cellular dNTP concentration in non-dividing cells. Here, we conducted the pre-steady-state kinetic analysis of reverse transcriptases (RTs) from two Vpx non-coding and two Vpx coding lentiviruses. At all three sites of the template tested, the two RTs of the Vpx non-coding viruses (HIV-1) displayed higher kpol values than the RTs of the Vpx coding HIV-2/SIV, whereas there was no significant difference in the Kd values of these two groups of RTs. When we employed viral RNA templates that induce RT pausing by their secondary structures, the HIV-1 RTs showed more efficient DNA synthesis through pause sites than the HIV-2/SIV RTs, particularly at low dNTP concentrations found in macrophages. This kinetic study suggests that RTs of the Vpx non-coding HIV-1 may have evolved to execute a faster kpol step, which includes the conformational changes and incorporation chemistry, to counteract the limited dNTP concentration found in non-dividing cells and still promote efficient viral reverse transcription. PMID:26483545

  20. Accumulate Repeat Accumulate Coded Modulation

    NASA Technical Reports Server (NTRS)

    Abbasfar, Aliazam; Divsalar, Dariush; Yao, Kung

    2004-01-01

    In this paper we propose an innovative coded modulation scheme called 'Accumulate Repeat Accumulate Coded Modulation' (ARA coded modulation). This class of codes can be viewed as serial turbo-like codes, or as a subclass of Low Density Parity Check (LDPC) codes that are combined with high level modulation. Thus at the decoder belief propagation can be used for iterative decoding of ARA coded modulation on a graph, provided a demapper transforms the received in-phase and quadrature samples to reliability of the bits.

  1. Fundamental differences between Arctic and Antarctic ozone depletion.

    PubMed

    Solomon, Susan; Haskins, Jessica; Ivy, Diane J; Min, Flora

    2014-04-29

    Antarctic ozone depletion is associated with enhanced chlorine from anthropogenic chlorofluorocarbons and heterogeneous chemistry under cold conditions. The deep Antarctic "hole" contrasts with the generally weaker depletions observed in the warmer Arctic. An unusually cold Arctic stratospheric season occurred in 2011, raising the question of how the Arctic ozone chemistry in that year compares with others. We show that the averaged depletions near 20 km across the cold part of each pole are deeper in Antarctica than in the Arctic for all years, although 2011 Arctic values do rival those seen in less-depleted years in Antarctica. We focus not only on averages but also on extremes, to address whether or not Arctic ozone depletion can be as extreme as that observed in the Antarctic. This information provides unique insights into the contrasts between Arctic and Antarctic ozone chemistry. We show that extreme Antarctic ozone minima fall to or below 0.1 parts per million by volume (ppmv) at 18 and 20 km (about 70 and 50 mbar) whereas the lowest Arctic ozone values are about 0.5 ppmv at these altitudes. At a higher altitude of 24 km (30-mbar level), no Arctic data below about 2 ppmv have been observed, including in 2011, in contrast to values more than an order of magnitude lower in Antarctica. The data show that the lowest ozone values are associated with temperatures below -80 °C to -85 °C depending upon altitude, and are closely associated with reduced gaseous nitric acid concentrations due to uptake and/or sedimentation in polar stratospheric cloud particles. PMID:24733920

  2. Iron depletion enhances the effect of sorafenib in hepatocarcinoma.

    PubMed

    Urano, Shinichi; Ohara, Toshiaki; Noma, Kazuhiro; Katsube, Ryoichi; Ninomiya, Takayuki; Tomono, Yasuko; Tazawa, Hiroshi; Kagawa, Shunsuke; Shirakawa, Yasuhiro; Kimura, Fumiaki; Nouso, Kazuhiro; Matsukawa, Akihiro; Yamamoto, Kazuhide; Fujiwara, Toshiyoshi

    2016-06-01

    ABSTACT Human hepatocellular carcinoma (HCC) is known to have a poor prognosis. Sorafenib, a molecular targeted drug, is most commonly used for HCC treatment. However, its effect on HCC is limited in clinical use and therefore new strategies regarding sorafenib treatment are required. Iron overload is known to be associated with progression of chronic hepatitis and increased risk of HCC. We previously reported that iron depletion inhibited cancer cell proliferation and conversely induced angiogenesis. Indeed iron depletion therapy including iron chelator needs to be combined with anti-angiogenic drug for its anti-cancer effect. Since sorafenib has an anti-angiogenic effect by its inhibitory targeting VEGFR, we hypothesized that sorafenib could complement the anti-cancer effect of iron depletion. We retrospectively analyzed the relationship between the efficacy of sorafenib and serum iron-related markers in clinical HCC patients. In clinical cases, overall survival was prolonged in total iron binding capacity (TIBC) high- and ferritin low-patients. This result suggested that the low iron-pooled patients, who could have a potential of more angiogenic properties in/around HCC tumors, could be adequate for sorafenib treatment. We determined the effect of sorafenib (Nexavar®) and/or deferasirox (EXJADE®) on cancer cell viability, and on cell signaling of human hepatocarcinoma HepG2 and HLE cells. Both iron depletion by deferasirox and sorafenib revealed insufficient cytotoxic effect by each monotherapy, however, on the basis of increased angiogenesis by iron depletion, the addition of deferasirox enhanced anti-proliferative effect of sorafenib. Deferasirox was confirmed to increase vascular endothelial growth factor (VEGF) secretion into cellular supernatants by ELISA analysis. In in vivo study sorafenib combined with deferasirox also enhanced sorafenib-induced apoptosis. These results suggested that sorafenib combined with deferasirox could be a novel combination

  3. Studies on Mechanisms of Hypocalcemia of Magnesium Depletion

    PubMed Central

    Reddy, Chilumula R.; Coburn, Jack W.; Hartenbower, David L.; Friedler, Robert M.; Brickman, Arnold S.; Massry, Shaul G.; Jowsey, Jenifer

    1973-01-01

    Studies were carried out to evaluate the mechanism of hypocalcemia in magnesium depletion. Day old chicks fed a magnesium deficient diet developed marked hypocalcemia, with a direct relation between serum calcium (y) and magnesium (x): y = 2.68 x + 4.24, r = 0.84 (both in mg/100 ml). Injections of parathyroid extract that increased serum calcium 2-3 mg/100 ml in normals had no effect in Mg-depleted birds. Very large dietary supplements of calcium or vitamin D3 increased mean serum calcium only from 5.3 to 7.7 and 7.8 mg/100 ml, respectively, while a normal magnesium diet for 3 days increased calcium from 5.3 to 9.9 mg/100 ml despite absence of dietary calcium. Intestinal calcium transport, studied in vitro, and the calcium concentration of the carcass was significantly increased in magnesium-depleted chicks, making it unlikely that reduced intestinal absorption of calcium caused the hypocalcemia. In magnesium-deficient chicks, the bone content of magnesium was decreased by 74%, the calcium content was unchanged, and the cortical thickness of bone was markedly increased. After 3 days of magnesium-repletion, cortical thickness was reduced with increased endosteal resorption. There was an increase in unmineralized osteoid tissue in the magnesium-depleted chicks. Parathyroid gland size and histology did not differ in magnesium-depleted and control birds. The results suggest that hypocalcemia develops due to altered equilibrium of calcium between extracellular fluid and bone, favoring increased net movement into the latter. Failure of parathyroid gland function could also exist, and unresponsiveness to parathyroid hormone (PTH) may also contribute to the hypocalcemia. However, failure of PTH action is probably due to the presence of excess osteoid tissue rather than a primary event leading to hypocalcemia. Images PMID:4750437

  4. Fundamental differences between Arctic and Antarctic ozone depletion

    PubMed Central

    Solomon, Susan; Haskins, Jessica; Ivy, Diane J.; Min, Flora

    2014-01-01

    Antarctic ozone depletion is associated with enhanced chlorine from anthropogenic chlorofluorocarbons and heterogeneous chemistry under cold conditions. The deep Antarctic “hole” contrasts with the generally weaker depletions observed in the warmer Arctic. An unusually cold Arctic stratospheric season occurred in 2011, raising the question of how the Arctic ozone chemistry in that year compares with others. We show that the averaged depletions near 20 km across the cold part of each pole are deeper in Antarctica than in the Arctic for all years, although 2011 Arctic values do rival those seen in less-depleted years in Antarctica. We focus not only on averages but also on extremes, to address whether or not Arctic ozone depletion can be as extreme as that observed in the Antarctic. This information provides unique insights into the contrasts between Arctic and Antarctic ozone chemistry. We show that extreme Antarctic ozone minima fall to or below 0.1 parts per million by volume (ppmv) at 18 and 20 km (about 70 and 50 mbar) whereas the lowest Arctic ozone values are about 0.5 ppmv at these altitudes. At a higher altitude of 24 km (30-mbar level), no Arctic data below about 2 ppmv have been observed, including in 2011, in contrast to values more than an order of magnitude lower in Antarctica. The data show that the lowest ozone values are associated with temperatures below −80 °C to −85 °C depending upon altitude, and are closely associated with reduced gaseous nitric acid concentrations due to uptake and/or sedimentation in polar stratospheric cloud particles. PMID:24733920

  5. Mouse liver protein sulfhydryl depletion after acetaminophen exposure.

    PubMed

    Yang, Xi; Greenhaw, James; Shi, Qiang; Roberts, Dean W; Hinson, Jack A; Muskhelishvili, Levan; Davis, Kelly; Salminen, William F

    2013-01-01

    Acetaminophen (APAP)-induced liver injury is the leading cause of acute liver failure in many countries. This study determined the extent of liver protein sulfhydryl depletion not only in whole liver homogenate but also in the zonal pattern of sulfhydryl depletion within the liver lobule. A single oral gavage dose of 150 or 300 mg/kg APAP in B6C3F1 mice produced increased serum alanine aminotransferase levels, liver necrosis, and glutathione depletion in a dose-dependent manner. Free protein sulfhydryls were measured in liver protein homogenates by labeling with maleimide linked to a near infrared fluorescent dye followed by SDS-polyacrylamide gel electrophoresis. Global protein sulfhydryl levels were decreased significantly (48.4%) starting at 1 hour after the APAP dose and maintained at this reduced level through 24 hours. To visualize the specific hepatocytes that had reduced protein sulfhydryl levels, frozen liver sections were labeled with maleimide linked to horseradish peroxidase. The centrilobular areas exhibited dramatic decreases in free protein sulfhydryls while the periportal regions were essentially spared. These protein sulfhydryl-depleted regions correlated with areas exhibiting histopathologic injury and APAP binding to protein. The majority of protein sulfhydryl depletion was due to reversible oxidation since the global- and lobule-specific effects were essentially reversed when the samples were reduced with tris(2-carboxyethy)phosphine before maleimide labeling. These temporal and zonal pattern changes in protein sulfhydryl oxidation shed new light on the importance that changes in protein redox status might play in the pathogenesis of APAP hepatotoxicity. PMID:23093024

  6. Oceanic bromoform emissions weighted by their ozone depletion potential

    NASA Astrophysics Data System (ADS)

    Tegtmeier, S.; Ziska, F.; Pisso, I.; Quack, B.; Velders, G. J. M.; Yang, X.; Krüger, K.

    2015-12-01

    At present, anthropogenic halogens and oceanic emissions of very short-lived substances (VSLSs) both contribute to the observed stratospheric ozone depletion. Emissions of the long-lived anthropogenic halogens have been reduced and are currently declining, whereas emissions of the biogenic VSLSs are expected to increase in future climate due to anthropogenic activities affecting oceanic production and emissions. Here, we introduce a new approach for assessing the impact of oceanic halocarbons on stratospheric ozone by calculating their ozone depletion potential (ODP)-weighted emissions. Seasonally and spatially dependent, global distributions are derived within a case-study framework for CHBr3 for the period 1999-2006. At present, ODP-weighted emissions of CHBr3 amount up to 50 % of ODP-weighted anthropogenic emissions of CFC-11 and to 9 % of all long-lived ozone depleting halogens. The ODP-weighted emissions are large where strong oceanic emissions coincide with high-reaching convective activity and show pronounced peaks at the Equator and the coasts with largest contributions from the Maritime Continent and western Pacific Ocean. Variations of tropical convective activity lead to seasonal shifts in the spatial distribution of the trajectory-derived ODP with the updraught mass flux, used as a proxy for trajectory-derived ODP, explaining 71 % of the variance of the ODP distribution. Future climate projections based on the RCP 8.5 scenario suggest a 31 % increase of the ODP-weighted CHBr3 emissions by 2100 compared to present values. This increase is related to a larger convective updraught mass flux in the upper troposphere and increasing emissions in a future climate. However, at the same time, it is reduced by less effective bromine-related ozone depletion due to declining stratospheric chlorine concentrations. The comparison of the ODP-weighted emissions of short- and long-lived halocarbons provides a new concept for assessing the overall impact of oceanic

  7. Depleted uranium hexafluoride: The source material for advanced shielding systems

    SciTech Connect

    Quapp, W.J.; Lessing, P.A.; Cooley, C.R.

    1997-02-01

    The U.S. Department of Energy (DOE) has a management challenge and financial liability problem in the form of 50,000 cylinders containing 555,000 metric tons of depleted uranium hexafluoride (UF{sub 6}) that are stored at the gaseous diffusion plants. DOE is evaluating several options for the disposition of this UF{sub 6}, including continued storage, disposal, and recycle into a product. Based on studies conducted to date, the most feasible recycle option for the depleted uranium is shielding in low-level waste, spent nuclear fuel, or vitrified high-level waste containers. Estimates for the cost of disposal, using existing technologies, range between $3.8 and $11.3 billion depending on factors such as the disposal site and the applicability of the Resource Conservation and Recovery Act (RCRA). Advanced technologies can reduce these costs, but UF{sub 6} disposal still represents large future costs. This paper describes an application for depleted uranium in which depleted uranium hexafluoride is converted into an oxide and then into a heavy aggregate. The heavy uranium aggregate is combined with conventional concrete materials to form an ultra high density concrete, DUCRETE, weighing more than 400 lb/ft{sup 3}. DUCRETE can be used as shielding in spent nuclear fuel/high-level waste casks at a cost comparable to the lower of the disposal cost estimates. Consequently, the case can be made that DUCRETE shielded casks are an alternative to disposal. In this case, a beneficial long term solution is attained for much less than the combined cost of independently providing shielded casks and disposing of the depleted uranium. Furthermore, if disposal is avoided, the political problems associated with selection of a disposal location are also avoided. Other studies have also shown cost benefits for low level waste shielded disposal containers.

  8. STRMDEPL08 - An Extended Version of STRMDEPL with Additional Analytical Solutions to Calculate Streamflow Depletion by Nearby Pumping Wells

    USGS Publications Warehouse

    Reeves, Howard W.

    2008-01-01

    STRMDEPL, a one-dimensional model using two analytical solutions to calculate streamflow depletion by a nearby pumping well, was extended to account for two additional analytical solutions. The extended program is named STRMDEPL08. The original program incorporated solutions for a stream that fully penetrates the aquifer with and without streambed resistance to ground-water flow. The modified program includes solutions for a partially penetrating stream with streambed resistance and for a stream in an aquitard subjected to pumping from an underlying leaky aquifer. The code also was modified to allow the user to input pumping variations at other than 1-day intervals. The modified code is shown to correctly evaluate the analytical solutions and to provide correct results for half-day time intervals.

  9. Multiple trellis coded modulation

    NASA Technical Reports Server (NTRS)

    Simon, Marvin K. (Inventor); Divsalar, Dariush (Inventor)

    1990-01-01

    A technique for designing trellis codes to minimize bit error performance for a fading channel. The invention provides a criteria which may be used in the design of such codes which is significantly different from that used for average white Gaussian noise channels. The method of multiple trellis coded modulation of the present invention comprises the steps of: (a) coding b bits of input data into s intermediate outputs; (b) grouping said s intermediate outputs into k groups of s.sub.i intermediate outputs each where the summation of all s.sub.i,s is equal to s and k is equal to at least 2; (c) mapping each of said k groups of intermediate outputs into one of a plurality of symbols in accordance with a plurality of modulation schemes, one for each group such that the first group is mapped in accordance with a first modulation scheme and the second group is mapped in accordance with a second modulation scheme; and (d) outputting each of said symbols to provide k output symbols for each b bits of input data.

  10. Code of Ethics.

    ERIC Educational Resources Information Center

    American Sociological Association, Washington, DC.

    The American Sociological Association's code of ethics for sociologists is presented. For sociological research and practice, 10 requirements for ethical behavior are identified, including: maintaining objectivity and integrity; fully reporting findings and research methods, without omission of significant data; reporting fully all sources of…

  11. Sharing the Code.

    ERIC Educational Resources Information Center

    Olsen, Florence

    2003-01-01

    Colleges and universities are beginning to consider collaborating on open-source-code projects as a way to meet critical software and computing needs. Points out the attractive features of noncommercial open-source software and describes some examples in use now, especially for the creation of Web infrastructure. (SLD)

  12. Electrical Circuit Simulation Code

    Energy Science and Technology Software Center (ESTSC)

    2001-08-09

    Massively-Parallel Electrical Circuit Simulation Code. CHILESPICE is a massively-arallel distributed-memory electrical circuit simulation tool that contains many enhanced radiation, time-based, and thermal features and models. Large scale electronic circuit simulation. Shared memory, parallel processing, enhance convergence. Sandia specific device models.

  13. The Redox Code

    PubMed Central

    Jones, Dean P.

    2015-01-01

    Abstract Significance: The redox code is a set of principles that defines the positioning of the nicotinamide adenine dinucleotide (NAD, NADP) and thiol/disulfide and other redox systems as well as the thiol redox proteome in space and time in biological systems. The code is richly elaborated in an oxygen-dependent life, where activation/deactivation cycles involving O2 and H2O2 contribute to spatiotemporal organization for differentiation, development, and adaptation to the environment. Disruption of this organizational structure during oxidative stress represents a fundamental mechanism in system failure and disease. Recent Advances: Methodology in assessing components of the redox code under physiological conditions has progressed, permitting insight into spatiotemporal organization and allowing for identification of redox partners in redox proteomics and redox metabolomics. Critical Issues: Complexity of redox networks and redox regulation is being revealed step by step, yet much still needs to be learned. Future Directions: Detailed knowledge of the molecular patterns generated from the principles of the redox code under defined physiological or pathological conditions in cells and organs will contribute to understanding the redox component in health and disease. Ultimately, there will be a scientific basis to a modern redox medicine. Antioxid. Redox Signal. 23, 734–746. PMID:25891126

  14. Environmental Fluid Dynamics Code

    EPA Science Inventory

    The Environmental Fluid Dynamics Code (EFDC)is a state-of-the-art hydrodynamic model that can be used to simulate aquatic systems in one, two, and three dimensions. It has evolved over the past two decades to become one of the most widely used and technically defensible hydrodyn...

  15. Heuristic dynamic complexity coding

    NASA Astrophysics Data System (ADS)

    Škorupa, Jozef; Slowack, Jürgen; Mys, Stefaan; Lambert, Peter; Van de Walle, Rik

    2008-04-01

    Distributed video coding is a new video coding paradigm that shifts the computational intensive motion estimation from encoder to decoder. This results in a lightweight encoder and a complex decoder, as opposed to the predictive video coding scheme (e.g., MPEG-X and H.26X) with a complex encoder and a lightweight decoder. Both schemas, however, do not have the ability to adapt to varying complexity constraints imposed by encoder and decoder, which is an essential ability for applications targeting a wide range of devices with different complexity constraints or applications with temporary variable complexity constraints. Moreover, the effect of complexity adaptation on the overall compression performance is of great importance and has not yet been investigated. To address this need, we have developed a video coding system with the possibility to adapt itself to complexity constraints by dynamically sharing the motion estimation computations between both components. On this system we have studied the effect of the complexity distribution on the compression performance. This paper describes how motion estimation can be shared using heuristic dynamic complexity and how distribution of complexity affects the overall compression performance of the system. The results show that the complexity can indeed be shared between encoder and decoder in an efficient way at acceptable rate-distortion performance.

  16. Code of Ethics.

    ERIC Educational Resources Information Center

    Association of College Unions-International, Bloomington, IN.

    The code of ethics for the college union and student activities professional is presented by the Association of College Unions-International. The preamble identifies the objectives of the college union as providing campus community centers and social programs that enhance the quality of life for members of the academic community. Ethics for…

  17. Dual Coding in Children.

    ERIC Educational Resources Information Center

    Burton, John K.; Wildman, Terry M.

    The purpose of this study was to test the applicability of the dual coding hypothesis to children's recall performance. The hypothesis predicts that visual interference will have a small effect on the recall of visually presented words or pictures, but that acoustic interference will cause a decline in recall of visually presented words and…

  18. The revised genetic code

    NASA Astrophysics Data System (ADS)

    Ninio, Jacques

    1990-03-01

    Recent findings on the genetic code are reviewed, including selenocysteine usage, deviations in the assignments of sense and nonsense codons, RNA editing, natural ribosomal frameshifts and non-orthodox codon-anticodon pairings. A multi-stage codon reading process is presented.

  19. Dress Codes and Uniforms.

    ERIC Educational Resources Information Center

    Lumsden, Linda; Miller, Gabriel

    2002-01-01

    Students do not always make choices that adults agree with in their choice of school dress. Dress-code issues are explored in this Research Roundup, and guidance is offered to principals seeking to maintain a positive school climate. In "Do School Uniforms Fit?" Kerry White discusses arguments for and against school uniforms and summarizes the…

  20. Code Optimization Techniques

    SciTech Connect

    MAGEE,GLEN I.

    2000-08-03

    Computers transfer data in a number of different ways. Whether through a serial port, a parallel port, over a modem, over an ethernet cable, or internally from a hard disk to memory, some data will be lost. To compensate for that loss, numerous error detection and correction algorithms have been developed. One of the most common error correction codes is the Reed-Solomon code, which is a special subset of BCH (Bose-Chaudhuri-Hocquenghem) linear cyclic block codes. In the AURA project, an unmanned aircraft sends the data it collects back to earth so it can be analyzed during flight and possible flight modifications made. To counter possible data corruption during transmission, the data is encoded using a multi-block Reed-Solomon implementation with a possibly shortened final block. In order to maximize the amount of data transmitted, it was necessary to reduce the computation time of a Reed-Solomon encoding to three percent of the processor's time. To achieve such a reduction, many code optimization techniques were employed. This paper outlines the steps taken to reduce the processing time of a Reed-Solomon encoding and the insight into modern optimization techniques gained from the experience.

  1. An Automated, Multi-Step Monte Carlo Burnup Code System.

    Energy Science and Technology Software Center (ESTSC)

    2003-07-14

    Version 02 MONTEBURNS Version 2 calculates coupled neutronic/isotopic results for nuclear systems and produces a large number of criticality and burnup results based on various material feed/removal specifications, power(s), and time intervals. MONTEBURNS is a fully automated tool that links the LANL MCNP Monte Carlo transport code with a radioactive decay and burnup code. Highlights on changes to Version 2 are listed in the transmittal letter. Along with other minor improvements in MONTEBURNS Version 2,more » the option was added to use CINDER90 instead of ORIGEN2 as the depletion/decay part of the system. CINDER90 is a multi-group depletion code developed at LANL and is not currently available from RSICC. This MONTEBURNS release was tested with various combinations of CCC-715/MCNPX 2.4.0, CCC-710/MCNP5, CCC-700/MCNP4C, CCC-371/ORIGEN2.2, ORIGEN2.1 and CINDER90. Perl is required software and is not included in this distribution. MCNP, ORIGEN2, and CINDER90 are not included.« less

  2. Development status of the lattice physics code in COSINE project

    SciTech Connect

    Chen, Y.; Yu, H.; Li, S.; Liu, Z.; Yan, Y.

    2013-07-01

    LATC is an essential part of COSINE code package, which stands for Core and System Integrated Engine for design and analysis. LATC performs 2D multi-group assembly transport calculation and generates few group constants and the required cross-section data for CORE, the core simulator code. LATC is designed to have the capability of modeling the API 000 series assemblies. The development is a continuously improved process. Currently, LATC uses well-proven technology to achieve the key functions. In the next stage, more advanced methods and modules will be implemented. At present, WIMS and WIMS improved format library could be read in LATC code. For resonance calculation, equivalent relation with rational approximations is utilized. For transport calculation, two options are available. One choice is collision probability method in cell homogenization while discrete coordinate method in assembly homogenization, the other is method of characteristics in assembly homogenization directly. For depletion calculation, an improved linear rate 'constant power' depletion method has been developed. (authors)

  3. An Automated, Multi-Step Monte Carlo Burnup Code System.

    SciTech Connect

    TRELLUE, HOLLY R.

    2003-07-14

    Version 02 MONTEBURNS Version 2 calculates coupled neutronic/isotopic results for nuclear systems and produces a large number of criticality and burnup results based on various material feed/removal specifications, power(s), and time intervals. MONTEBURNS is a fully automated tool that links the LANL MCNP Monte Carlo transport code with a radioactive decay and burnup code. Highlights on changes to Version 2 are listed in the transmittal letter. Along with other minor improvements in MONTEBURNS Version 2, the option was added to use CINDER90 instead of ORIGEN2 as the depletion/decay part of the system. CINDER90 is a multi-group depletion code developed at LANL and is not currently available from RSICC. This MONTEBURNS release was tested with various combinations of CCC-715/MCNPX 2.4.0, CCC-710/MCNP5, CCC-700/MCNP4C, CCC-371/ORIGEN2.2, ORIGEN2.1 and CINDER90. Perl is required software and is not included in this distribution. MCNP, ORIGEN2, and CINDER90 are not included.

  4. The influence of ego depletion on sprint start performance in athletes without track and field experience

    PubMed Central

    Englert, Chris; Persaud, Brittany N.; Oudejans, Raôul R. D.; Bertrams, Alex

    2015-01-01

    We tested the assumption that ego depletion would affect the sprint start in a sample of N = 38 athletes without track and field experience in an experiment by applying a mixed between- (depletion vs. non-depletion) within- (T1: before manipulation of ego depletion vs. T2: after manipulation of ego depletion) subjects design. We assumed that ego depletion would increase the possibility for a false start, as regulating the impulse to initiate the sprinting movement too soon before the starting signal requires self-control. In line with our assumption, we found a significant interaction as there was only a significant increase in the number of false starts from T1 to T2 for the depletion group while this was not the case for the non-depletion group. We conclude that ego depletion has a detrimental influence on the sprint start in athletes without track and field experience. PMID:26347678

  5. Offsetting Streamflow Depletion from Well Pumpage by Capture of Evapotranspiration

    NASA Astrophysics Data System (ADS)

    Konikow, L. F.

    2014-12-01

    It is well established that groundwater pumpage must be balanced by a loss of water elsewhere. This loss comes primarily from storage depletion at early times and increasingly from capture at later times. Capture includes some combination of increases in recharge to the aquifer and decreases in discharge from the aquifer induced by the pumpage. Most capture is manifested as streamflow depletion (e.g., through induced infiltration and/or reductions in baseflow). However, decreasing evapotransirative discharge from an aquifer would constitute a type of capture that does not affect streamflow. In his classic 1940 paper Theis recommends that wells be placed in areas where groundwater "is being lost by evaporation or transpiration by non-productive vegetation," thereby utilizing this "lost" water with a minimal lowering of the water table. This study uses numerical simulation of a hypothetical unconfined stream-aquifer system in an arid climate, where streamflow depletion is typically a major concern, to assess how capture of evapotranspiration (ET) can influence the sources of water for a pumping well when the ET losses are directly affected by spatial and temporal changes in the depth to the water table. Consequently, streamflow depletion for a given pumping rate can be affected by capture of ET and how that varies with well location and the history of development and drawdown. We assume the standard MODFLOW linear model for changes in groundwater ET as the water table declines to a specified extinction depth. In one scenario in which about half the recharge to the aquifer is lost to ET under predevelopment conditions, the percentage of well discharge balanced by decreased ET changed from 1.1% after one year to 18% after 200 years of simulated pumpage. The actual ET rate decreased from 5,372 m3/d under predevelopment conditions to 5,001 m3/d after 200 years of development (a 7% reduction in total ET losses). At this same time, 77% of pumpage is derived from streamflow

  6. Evaluating groundwater depletion as computed by a global water model

    NASA Astrophysics Data System (ADS)

    Schuh, Carina; Doell, Petra; Mueller Schmied, Hannes; Portmann, Felix

    2013-04-01

    When groundwater abstraction occurs faster than its replenishment over a long time and in a large area, the result is an overexploitation or depletion of groundwater. The problem is aggravated in areas where a growing population relies on freshwater resources for an intensive irrigation agriculture that is meant to guarantee food security. Especially in semi-arid and arid regions, the dominant use for groundwater is irrigation, reaching more than 95% of total water use. Therefore, the hot spots for groundwater depletion are the world's major irrigation areas like the central United States, north-western India and north China. Groundwater depletion presents a major threat to securing agricultural productivity and domestic water supply in these parts of the world. Besides, the environmental consequences that accompany the abstraction of groundwater are severe. Within the scientific community there is a common understanding that high-quality data on globally existing groundwater resources are deficient. In order to allow a sustainable management of the world's available groundwater resources, especially in areas under current water stress, the quantification of groundwater depletion is of high importance. WaterGAP (Water - Global Assessment and Prognosis) is a global model of water availability and water use which can serve to estimate the impact of groundwater and surface water withdrawals on groundwater storage. The new WaterGAP version 2.2a was modified to allow for an improved analysis of groundwater storage changes in semi-arid and arid regions. Now, groundwater recharge from surface water bodies is simulated in semi-arid and arid areas. Estimation of net groundwater abstractions was modified with respect of irrigation water use efficiency for groundwater and return flow fractions. In addition, irrigation consumptive use has been set to 70% of optimal irrigation consumptive use, assuming deficit irrigation to prevail in these parts of the world. Based on time

  7. The follicle-deplete mouse ovary produces androgen.

    PubMed

    Mayer, Loretta P; Devine, Patrick J; Dyer, Cheryl A; Hoyer, Patricia B

    2004-07-01

    The follicle-depleted postmenopausal ovary is enriched in interstitial cells that produce androgens. This study was designed to cause follicle depletion in mice using the industrial chemical, 4-vinylcyclohexene diepoxide (VCD), and characterize the steroidogenic capacity of cells in the residual ovarian tissue. From a dose-finding study, the optimal daily concentration of VCD was determined to be 160 mg/kg. Female B6C3F(1) immature mice were treated daily with vehicle control or VCD (160 mg kg(-1) day(-1), 15 days, i.p.). Ovaries were removed and processed for histological evaluation. On Day 15 following onset of treatment, primordial follicles were depleted and primary follicles were reduced to about 10% of controls. On Day 46, primary follicles were depleted and secondary and antral follicles were reduced to 0.7% and 2.6% of control, respectively. Seventy-five percent of treated mice displayed disruptions in estrous cyclicity. All treated mice were in persistent diestrus (acyclic) by Day 58. Plasma FSH levels were increased (P < 0.05) relative to controls on Day 37 and had plateaued by Day 100. Relative to age-matched cyclic controls, by Day 127, the significant differences in VCD-treated mice included reduced ovarian and uterine weights, elevated plasma LH and FSH, and reduced plasma progesterone and androstenedione. Furthermore, plasma 17beta-estradiol levels were nondetectable. Unlike controls, immunostaining for LH receptor, and the high density lipoprotein receptor (SR-BI), was diffuse in ovarian sections from VCD-treated animals. Ovaries from Day 120 control and VCD-treated animals were dissociated and dispersed cells were placed in culture. Cultured cells from ovaries of VCD-treated animals produced less LH-stimulated progesterone than control cells. Androstenedione production was nondetectable in cells from cyclic control animals. Conversely, cells from VCD-treated animals produced androstenedione that was doubled in the presence of insulin and LH (1 and

  8. Binary coding for hyperspectral imagery

    NASA Astrophysics Data System (ADS)

    Wang, Jing; Chang, Chein-I.; Chang, Chein-Chi; Lin, Chinsu

    2004-10-01

    Binary coding is one of simplest ways to characterize spectral features. One commonly used method is a binary coding-based image software system, called Spectral Analysis Manager (SPAM) for remotely sensed imagery developed by Mazer et al. For a given spectral signature, the SPAM calculates its spectral mean and inter-band spectral difference and uses them as thresholds to generate a binary code word for this particular spectral signature. Such coding scheme is generally effective and also very simple to implement. This paper revisits the SPAM and further develops three new SPAM-based binary coding methods, called equal probability partition (EPP) binary coding, halfway partition (HP) binary coding and median partition (MP) binary coding. These three binary coding methods along with the SPAM well be evaluated for spectral discrimination and identification. In doing so, a new criterion, called a posteriori discrimination probability (APDP) is also introduced for performance measure.

  9. Sinusoidal transform coding

    NASA Technical Reports Server (NTRS)

    Mcaulay, Robert J.; Quatieri, Thomas F.

    1988-01-01

    It has been shown that an analysis/synthesis system based on a sinusoidal representation of speech leads to synthetic speech that is essentially perceptually indistinguishable from the original. Strategies for coding the amplitudes, frequencies and phases of the sine waves have been developed that have led to a multirate coder operating at rates from 2400 to 9600 bps. The encoded speech is highly intelligible at all rates with a uniformly improving quality as the data rate is increased. A real-time fixed-point implementation has been developed using two ADSP2100 DSP chips. The methods used for coding and quantizing the sine-wave parameters for operation at the various frame rates are described.

  10. Finite Element Analysis Code

    Energy Science and Technology Software Center (ESTSC)

    2006-03-08

    MAPVAR-KD is designed to transfer solution results from one finite element mesh to another. MAPVAR-KD draws heavily from the structure and coding of MERLIN II, but it employs a new finite element data base, EXODUS II, and offers enhanced speed and new capabilities not available in MERLIN II. In keeping with the MERLIN II documentation, the computational algorithms used in MAPVAR-KD are described. User instructions are presented. Example problems are included to demonstrate the operationmore » of the code and the effects of various input options. MAPVAR-KD is a modification of MAPVAR in which the search algorithm was replaced by a kd-tree-based search for better performance on large problems.« less

  11. Confocal coded aperture imaging

    DOEpatents

    Tobin, Jr., Kenneth William; Thomas, Jr., Clarence E.

    2001-01-01

    A method for imaging a target volume comprises the steps of: radiating a small bandwidth of energy toward the target volume; focusing the small bandwidth of energy into a beam; moving the target volume through a plurality of positions within the focused beam; collecting a beam of energy scattered from the target volume with a non-diffractive confocal coded aperture; generating a shadow image of said aperture from every point source of radiation in the target volume; and, reconstructing the shadow image into a 3-dimensional image of the every point source by mathematically correlating the shadow image with a digital or analog version of the coded aperture. The method can comprise the step of collecting the beam of energy scattered from the target volume with a Fresnel zone plate.

  12. CTI Correction Code

    NASA Astrophysics Data System (ADS)

    Massey, Richard; Stoughton, Chris; Leauthaud, Alexie; Rhodes, Jason; Koekemoer, Anton; Ellis, Richard; Shaghoulian, Edgar

    2013-07-01

    Charge Transfer Inefficiency (CTI) due to radiation damage above the Earth's atmosphere creates spurious trailing in images from Charge-Coupled Device (CCD) imaging detectors. Radiation damage also creates unrelated warm pixels, which can be used to measure CTI. This code provides pixel-based correction for CTI and has proven effective in Hubble Space Telescope Advanced Camera for Surveys raw images, successfully reducing the CTI trails by a factor of ~30 everywhere in the CCD and at all flux levels. The core is written in java for speed, and a front-end user interface is provided in IDL. The code operates on raw data by returning individual electrons to pixels from which they were unintentionally dragged during readout. Correction takes about 25 minutes per ACS exposure, but is trivially parallelisable to multiple processors.

  13. Status of MARS Code

    SciTech Connect

    N.V. Mokhov

    2003-04-09

    Status and recent developments of the MARS 14 Monte Carlo code system for simulation of hadronic and electromagnetic cascades in shielding, accelerator and detector components in the energy range from a fraction of an electronvolt up to 100 TeV are described. these include physics models both in strong and electromagnetic interaction sectors, variance reduction techniques, residual dose, geometry, tracking, histograming. MAD-MARS Beam Line Build and Graphical-User Interface.

  14. VAC: Versatile Advection Code

    NASA Astrophysics Data System (ADS)

    Tóth, Gábor; Keppens, Rony

    2012-07-01

    The Versatile Advection Code (VAC) is a freely available general hydrodynamic and magnetohydrodynamic simulation software that works in 1, 2 or 3 dimensions on Cartesian and logically Cartesian grids. VAC runs on any Unix/Linux system with a Fortran 90 (or 77) compiler and Perl interpreter. VAC can run on parallel machines using either the Message Passing Interface (MPI) library or a High Performance Fortran (HPF) compiler.

  15. Reeds computer code

    NASA Technical Reports Server (NTRS)

    Bjork, C.

    1981-01-01

    The REEDS (rocket exhaust effluent diffusion single layer) computer code is used for the estimation of certain rocket exhaust effluent concentrations and dosages and their distributions near the Earth's surface following a rocket launch event. Output from REEDS is used in producing near real time air quality and environmental assessments of the effects of certain potentially harmful effluents, namely HCl, Al2O3, CO, and NO.

  16. MELCOR computer code manuals

    SciTech Connect

    Summers, R.M.; Cole, R.K. Jr.; Smith, R.C.; Stuart, D.S.; Thompson, S.L.; Hodge, S.A.; Hyman, C.R.; Sanders, R.L.

    1995-03-01

    MELCOR is a fully integrated, engineering-level computer code that models the progression of severe accidents in light water reactor nuclear power plants. MELCOR is being developed at Sandia National Laboratories for the U.S. Nuclear Regulatory Commission as a second-generation plant risk assessment tool and the successor to the Source Term Code Package. A broad spectrum of severe accident phenomena in both boiling and pressurized water reactors is treated in MELCOR in a unified framework. These include: thermal-hydraulic response in the reactor coolant system, reactor cavity, containment, and confinement buildings; core heatup, degradation, and relocation; core-concrete attack; hydrogen production, transport, and combustion; fission product release and transport; and the impact of engineered safety features on thermal-hydraulic and radionuclide behavior. Current uses of MELCOR include estimation of severe accident source terms and their sensitivities and uncertainties in a variety of applications. This publication of the MELCOR computer code manuals corresponds to MELCOR 1.8.3, released to users in August, 1994. Volume 1 contains a primer that describes MELCOR`s phenomenological scope, organization (by package), and documentation. The remainder of Volume 1 contains the MELCOR Users Guides, which provide the input instructions and guidelines for each package. Volume 2 contains the MELCOR Reference Manuals, which describe the phenomenological models that have been implemented in each package.

  17. Bar coded retroreflective target

    DOEpatents

    Vann, Charles S.

    2000-01-01

    This small, inexpensive, non-contact laser sensor can detect the location of a retroreflective target in a relatively large volume and up to six degrees of position. The tracker's laser beam is formed into a plane of light which is swept across the space of interest. When the beam illuminates the retroreflector, some of the light returns to the tracker. The intensity, angle, and time of the return beam is measured to calculate the three dimensional location of the target. With three retroreflectors on the target, the locations of three points on the target are measured, enabling the calculation of all six degrees of target position. Until now, devices for three-dimensional tracking of objects in a large volume have been heavy, large, and very expensive. Because of the simplicity and unique characteristics of this tracker, it is capable of three-dimensional tracking of one to several objects in a large volume, yet it is compact, light-weight, and relatively inexpensive. Alternatively, a tracker produces a diverging laser beam which is directed towards a fixed position, and senses when a retroreflective target enters the fixed field of view. An optically bar coded target can be read by the tracker to provide information about the target. The target can be formed of a ball lens with a bar code on one end. As the target moves through the field, the ball lens causes the laser beam to scan across the bar code.

  18. Suboptimum decoding of block codes

    NASA Technical Reports Server (NTRS)

    Lin, Shu; Kasami, Tadao

    1991-01-01

    This paper investigates a class of decomposable codes, their distance and structural properties. it is shown that this class includes several classes of well known and efficient codes as subclasses. Several methods for constructing decomposable codes or decomposing codes are presented. A two-stage soft decision decoding scheme for decomposable codes, their translates or unions of translates is devised. This two-stage soft-decision decoding is suboptimum, and provides an excellent trade-off between the error performance and decoding complexity for codes of moderate and long block length.

  19. Preliminary Assessment of Turbomachinery Codes

    NASA Technical Reports Server (NTRS)

    Mazumder, Quamrul H.

    2007-01-01

    This report assesses different CFD codes developed and currently being used at Glenn Research Center to predict turbomachinery fluid flow and heat transfer behavior. This report will consider the following codes: APNASA, TURBO, GlennHT, H3D, and SWIFT. Each code will be described separately in the following section with their current modeling capabilities, level of validation, pre/post processing, and future development and validation requirements. This report addresses only previously published and validations of the codes. However, the codes have been further developed to extend the capabilities of the codes.

  20. Structural coding versus free-energy predictive coding.

    PubMed

    van der Helm, Peter A

    2016-06-01

    Focusing on visual perceptual organization, this article contrasts the free-energy (FE) version of predictive coding (a recent Bayesian approach) to structural coding (a long-standing representational approach). Both use free-energy minimization as metaphor for processing in the brain, but their formal elaborations of this metaphor are fundamentally different. FE predictive coding formalizes it by minimization of prediction errors, whereas structural coding formalizes it by minimization of the descriptive complexity of predictions. Here, both sides are evaluated. A conclusion regarding competence is that FE predictive coding uses a powerful modeling technique, but that structural coding has more explanatory power. A conclusion regarding performance is that FE predictive coding-though more detailed in its account of neurophysiological data-provides a less compelling cognitive architecture than that of structural coding, which, for instance, supplies formal support for the computationally powerful role it attributes to neuronal synchronization. PMID:26407895

  1. Effects of Stratospheric Ozone Depletion the Environment and Agriculture

    NASA Astrophysics Data System (ADS)

    Ali, S. M.; Dash, Nutan Ku; Pradhan, Arjyadhara; Mishra, Sthita Prajna

    2012-09-01

    Ozone depletion results in greater amounts of UV-B radiation that had an impact on terrestrial and aquatic biogeochemical systems. Biogeochemical cycles were the complex interactions of physical, chemical, geological and biological processes that control the transport and transformation of substances in the natural environment and therefore the conditions that humans experience in Earth's system. The increased UV-B radiation impinging on terrestrial and aquatic systems, due to ozone depletion, results in changes in the trace gas exchange between the continents, oceans and the atmosphere. This had result in complex alterations to atmospheric chemistry, the global elemental cycles such as the carbon cycle, and had an impact on the survival and health of all organisms on Earth, including humans.

  2. Mass depletion: A new parameter for quantitative jet modification

    NASA Astrophysics Data System (ADS)

    Majumder, A.; Putschke, J.

    2016-05-01

    We propose an extension to classify jet modification in heavy-ion collisions by including the jet mass along with its energy. The mass of a jet, as measured by jet reconstruction algorithms, is constrained by the jet's virtuality, which in turn has a considerable effect on such observables as the fragmentation function and jet shape observables. The leading parton, propagating through a dense medium, experiences substantial virtuality (or mass) depletion along with energy loss. Meaningful comparisons between surviving jets and jets produced in p -p collisions require mass depletion to be taken into account. Using a vacuum event generator, we show the close relationship between the actual jet mass and that after applying a jet reconstruction algorithm. Using an in-medium event generator, we demonstrate the clear difference between the mass of a surviving parton exiting a dense medium and a parton with a similar energy formed in a hard scattering event. Effects of this difference on jet observables are discussed.

  3. Lower hybrid wave phenomena associated with density depletions

    NASA Technical Reports Server (NTRS)

    Seyler, C. E.

    1994-01-01

    A fluid description of lower hybrid, whistler and magnetosonic waves is applied to study wave phenomena near the lower hybrid resonance associated with plasma density depletions. The goal is to understand the nature of lower hybrid cavitons and spikelets often associated with transverse ion acceleration events in the auroral ionosphere. Three-dimensional simulations show the ponderomotive force leads to the formation of a density cavity (caviton) in which lower hybrid wave energy is concentrated (spikelet) resulting in a three-dimensional collapse of the configuration. Plasma density depletions of the order of a few percent are shown to greatly modify the homogeneous linear properties of lower hybrid waves and account for many of the observed features of lower hybrid spikelets.

  4. Neutrophil depletion delays wound repair in aged mice

    PubMed Central

    Nishio, Naomi; Okawa, Yayoi; Sakurai, Hidetoshi

    2008-01-01

    One of the most important clinical problems in caring for elderly patients is treatment of pressure ulcers. One component of normal wound healing is the generation of an inflammatory reaction, which is characterized by the sequential infiltration of neutrophils, macrophages and lymphocytes. Neutrophils migrate early in the wound healing process. In aged C57BL/6 mice, wound healing is relatively inefficient. We examined the effects of neutrophil numbers on wound healing in both young and aged mice. We found that the depletion of neutrophils by anti-Gr-1 antibody dramatically delayed wound healing in aged mice. The depletion of neutrophils in young mice had less effect on the kinetics of wound healing. Intravenous G-CSF injection increased the migration of neutrophils to the wound site. While the rate of wound repair did not change significantly in young mice following G-CSF injection, it increased significantly in old mice. PMID:19424869

  5. Effect of temperature coupling on ozone depletion prediction

    NASA Technical Reports Server (NTRS)

    Chandra, S.; Butler, D. M.; Stolarski, R. S.

    1978-01-01

    The effects of chlorine perturbations on both the temperature and the ozone distribution in the stratosphere have been studied using a simplified radiative-photochemical model. The model solves the hydrostatic equation for total density in a self-consistent manner as the temperature is changed. Radiative coupling is found to have a significant effect on both the thermal structure and the ozone distribution, particularly in the 35-50-km region. By increasing the ClX mixing ratio by 5.0 ppbv, the temperature in this region is decreased by 5 to 10 K with a slight increase below 30 km. The local ozone depletion around 40 km due to added ClX is smaller compared with the estimate made by keeping the temperature fixed to the ambient condition. However, the integrated effect of radiative coupling is to increase the calculated column ozone depletion by 15% to 25% in this model.

  6. Visualization of stratospheric ozone depletion and the polar vortex

    NASA Technical Reports Server (NTRS)

    Treinish, Lloyd A.

    1995-01-01

    Direct analysis of spacecraft observations of stratospheric ozone yields information about the morphology of annual austral depletion. Visual correlation of ozone with other atmospheric data illustrates the diurnal dynamics of the polar vortex and contributions from the upper troposphere, including the formation and breakup of the depletion region each spring. These data require care in their presentation to minimize the introduction of visualization artifacts that are erroneously interpreted as data features. Non geographically registered data of differing mesh structures can be visually correlated via cartographic warping of base geometries without interpolation. Because this approach is independent of the realization technique, it provides a framework for experimenting with many visualization strategies. This methodology preserves the fidelity of the original data sets in a coordinate system suitable for three-dimensional, dynamic examination of atmospheric phenomena.

  7. Currents through Hv1 channels deplete protons in their vicinity

    PubMed Central

    De-la-Rosa, Víctor; Suárez-Delgado, Esteban; Rangel-Yescas, Gisela E.

    2016-01-01

    Proton channels have evolved to provide a pH regulatory mechanism, affording the extrusion of protons from the cytoplasm at all membrane potentials. Previous evidence has suggested that channel-mediated acid extrusion could significantly change the local concentration of protons in the vicinity of the channel. In this work, we directly measure the proton depletion caused by activation of Hv1 proton channels using patch-clamp fluorometry recordings from channels labeled with the Venus fluorescent protein at intracellular domains. The fluorescence of the Venus protein is very sensitive to pH, thus behaving as a genetically encoded sensor of local pH. Eliciting outward proton currents increases the fluorescence intensity of Venus. This dequenching is related to the magnitude of the current and not to channel gating and is dependent on the pH gradient. Our results provide direct evidence of local proton depletion caused by flux through the proton-selective channel. PMID:26809792

  8. Currents through Hv1 channels deplete protons in their vicinity.

    PubMed

    De-la-Rosa, Víctor; Suárez-Delgado, Esteban; Rangel-Yescas, Gisela E; Islas, León D

    2016-02-01

    Proton channels have evolved to provide a pH regulatory mechanism, affording the extrusion of protons from the cytoplasm at all membrane potentials. Previous evidence has suggested that channel-mediated acid extrusion could significantly change the local concentration of protons in the vicinity of the channel. In this work, we directly measure the proton depletion caused by activation of Hv1 proton channels using patch-clamp fluorometry recordings from channels labeled with the Venus fluorescent protein at intracellular domains. The fluorescence of the Venus protein is very sensitive to pH, thus behaving as a genetically encoded sensor of local pH. Eliciting outward proton currents increases the fluorescence intensity of Venus. This dequenching is related to the magnitude of the current and not to channel gating and is dependent on the pH gradient. Our results provide direct evidence of local proton depletion caused by flux through the proton-selective channel. PMID:26809792

  9. Shock induced multi-mode damage in depleted uranium

    SciTech Connect

    Koller, Darcie D; Cerreta, Ellen K; Gray, Ill, George T

    2009-01-01

    Recent dynamic damage studies on depleted uranium samples have revealed mixed mode failure mechanisms leading to incipient cracking as well as ductile failure processes. Results show that delamination of inclusions upon compression may provide nucleation sites for damage initiation in the form of crack tip production. However, under tension the material propagates cracks in a mixed shear localization and mode-I ductile tearing and cracking. Cracks tips appear to link up through regions of severe, shear dominated plastic flow. Shock recovery experiments were conducted on a 50 mm single stage light gas gun. Serial metallographic sectioning was conducted on the recovered samples to characterize the bulk response of the sample. Experiments show delaminated inclusions due to uniaxial compression without damage propagation. Further results show the propagation of the damage through tensile loading to the incipient state, illustrating ductile processes coupled with mixed mode-I tensile ductile tearing, shear localization, and mode-I cracking in depleted uranium.

  10. High pressure elasticity and thermal properties of depleted uranium

    NASA Astrophysics Data System (ADS)

    Jacobsen, M. K.; Velisavljevic, N.

    2016-04-01

    Studies of the phase diagram of uranium have revealed a wealth of high pressure and temperature phases. Under ambient conditions the crystal structure is well defined up to 100 gigapascals (GPa), but very little information on thermal conduction or elasticity is available over this same range. This work has applied ultrasonic interferometry to determine the elasticity, mechanical, and thermal properties of depleted uranium to 4.5 GPa. Results show general strengthening with applied load, including an overall increase in acoustic thermal conductivity. Further implications are discussed within. This work presents the first high pressure studies of the elasticity and thermal properties of depleted uranium metal and the first real-world application of a previously developed containment system for making such measurements.

  11. Copper-triazole interaction and coolant inhibitor depletion

    SciTech Connect

    Bartley, L.S.; Fritz, P.O.; Pellet, R.J.; Taylor, S.A.; Van de Ven, P.

    1999-08-01

    To a large extent, the depletion of tolyltriazole (TTZ) observed in several field tests may be attributed to the formation of a protective copper-triazole layer. Laboratory aging studies, shown to correlate with field experience, reveal that copper-TTZ layer formation depletes coolant TTZ levels in a fashion analogous to changes observed in the field. XPS and TPD-MS characterization of the complex formed indicates a strong chemical bond between copper and the adsorbed TTZ which can be desorbed thermally only at elevated temperatures. Electrochemical polarization experiments indicate that the layer provides good copper protection even when TTZ is absent from the coolant phase. Examination of copper cooling system components obtained after extensive field use reveals the presence of a similar protective layer.

  12. Do antidepressants cause folic acid depletion? A pilot study

    PubMed Central

    Farrell, K.A.; Jamjoom, S.; Donaldson, D.; Dickerson, J.W.T.

    1988-01-01

    Chronic administration of tricyclic antidepressants is common; folic acid depletion is a potential consequence adversely affecting the mental state. In a pilot study prior to research in the community, serum and red cell folate and serum vitamin B 12 levels were measured in the following elderly psychiatric inpatients: 14 controls (patients not receiving any drugs with known antifolate activity), 11 receiving tricyclic antidepressants, 13 receiving antipsychotics (phenothiazines) and four receiving an anticonvulsant (carbamazepine). Patients on prolonged treatment with carbamazepine or phenothiazine drugs had lower concentrations of folate in serum and erythrocytes compared with controls; the decrease was statistically significant for the effect of phenothiazines on serum folate levels. Tricyclic antidepressants, which are in widespread use in the community, did not cause folate depletion during the first two years of treatment. PMID:3204543

  13. Nuclear structure and depletion of nuclear isomers using electron linacs

    SciTech Connect

    Carroll, J. J.; Litz, M. S.; Henriquez, S. L.; Burns, D. A.; Netherton, K. A.; Pereira, N. R.; Karamian, S. A.

    2013-04-19

    Long-lived nuclear excited states (isomers) have proven important to understanding nuclear structure. With some isomers having half-lives of decades or longer, and intrinsic energy densities reaching 10{sup 12} J/kg, they have also been suggested for a wide range of applications. The ability to effectively transfer a population of nuclei from an isomer to shorter-lived levels will determine the feasibility of any applications. Here is described a first demonstration of the induced depletion of a population of the 438 year isomer of {sup 108}Ag to its 2.38 min ground state, using 6 MeV bremsstrahlung from a modified medical electron linac. The experiment suggests refinements to be implemented in the future and how a similar approach might be applied to study induced depletion of the 1200 year isomer of {sup 166}Ho.

  14. Convolutional coding techniques for data protection

    NASA Technical Reports Server (NTRS)

    Massey, J. L.

    1975-01-01

    Results of research on the use of convolutional codes in data communications are presented. Convolutional coding fundamentals are discussed along with modulation and coding interaction. Concatenated coding systems and data compression with convolutional codes are described.

  15. Modeling of the dispersion of depleted uranium aerosol.

    PubMed

    Mitsakou, C; Eleftheriadis, K; Housiadas, C; Lazaridis, M

    2003-04-01

    Depleted uranium is a low-cost radioactive material that, in addition to other applications, is used by the military in kinetic energy weapons against armored vehicles. During the Gulf and Balkan conflicts concern has been raised about the potential health hazards arising from the toxic and radioactive material released. The aerosol produced during impact and combustion of depleted uranium munitions can potentially contaminate wide areas around the impact sites or can be inhaled by civilians and military personnel. Attempts to estimate the extent and magnitude of the dispersion were until now performed by complex modeling tools employing unclear assumptions and input parameters of high uncertainty. An analytical puff model accommodating diffusion with simultaneous deposition is developed, which can provide a reasonable estimation of the dispersion of the released depleted uranium aerosol. Furthermore, the period of the exposure for a given point downwind from the release can be estimated (as opposed to when using a plume model). The main result is that the depleted uranium mass is deposited very close to the release point. The deposition flux at a couple of kilometers from the release point is more than one order of magnitude lower than the one a few meters near the release point. The effects due to uncertainties in the key input variables are addressed. The most influential parameters are found to be atmospheric stability, height of release, and wind speed, whereas aerosol size distribution is less significant. The output from the analytical model developed was tested against the numerical model RPM-AERO. Results display satisfactory agreement between the two models. PMID:12705453

  16. Macrophage depletion ameliorates nephritis induced by pathogenic antibodies

    PubMed Central

    Chalmers, Samantha A.; Chitu, Violeta; Herlitz, Leal C.; Sahu, Ranjit; Stanley, E. Richard; Putterman, Chaim

    2014-01-01

    Objective Kidney involvement affects 40–60% of patients with lupus and is responsible for significant morbidity and mortality. Using depletion approaches, several studies have suggested that macrophages may play a key role in the pathogenesis of lupus nephritis. However, “off target” effects of macrophage depletion, such as altered hematopoiesis or enhanced autoantibody production, impeded the determination of a conclusive relationship. Methods In this study, we investigated the role of macrophages in mice receiving rabbit anti-glomerular antibodies, or nephrotoxic serum (NTS), an experimental model which closely mimics the immune complex mediated disease seen in murine and human lupus nephritis. GW2580, a selective inhibitor of the colony stimulating factor-1 (CSF-1) receptor kinase, was used for macrophage depletion. Results We found that GW2580-treated, NTS challenged mice did not develop the increased levels of proteinuria, serum creatinine, or serum urea seen in control-treated, NTS challenged mice. NTS challenged mice exhibited significantly increased kidney expression of inflammatory cytokines including RANTES, IP-10, VCAM-1 and iNOS, whereas GW2580-treated mice were protected from the robust expression of these inflammatory cytokines that are associated with LN. Quantification of macrophage related gene expression, flow cytometry analysis of kidney single cell suspensions, and immunofluorescence staining confirmed the depletion of macrophages in GW2580-treated mice, specifically within renal glomeruli. Conclusions Our results strongly implicate a specific and necessary role for macrophages in the development of immune glomerulonephritis mediated by pathogenic antibodies, and support the development of macrophage targeting approaches for the treatment of lupus nephritis. PMID:25554644

  17. Stimulated emission depletion microscopy to study amyloid fibril formation

    NASA Astrophysics Data System (ADS)

    Mahou, Pierre; Curry, Nathan; Pinotsi, Dorothea; Kaminski Schierle, Gabriele; Kaminski, Clemens

    2015-03-01

    Aggregation of misfolded proteins is a characteristic hallmark of many neurodegenerative disorders, such as Parkinson's, Alzheimer's and Huntington's diseases. The ability to observe these aggregation processes and the corresponding structures formed in vitro or in situ is therefore a key requirement to understand the molecular mechanisms of these diseases. We report here on the implementation and application of Stimulated Emission Depletion (STED) microscopy to visualize the formation of amyloid fibrils in vitro.

  18. Ozone depletion at temperature warmer than TNAT in the Arctic

    NASA Astrophysics Data System (ADS)

    Pommereau, J.; Goutail, F.; Pazmino, A.; Lefevre, F.; Pitts, M. C.

    2011-12-01

    The unprecedented ozone destruction in the Arctic vortex in 2011 that extended until the end of March offers a unique opportunity for testing the relationship between temperature, responsible for heterogeneous chlorine activation on PSCs and aerosols and the amplitude of ozone loss. Indeed, as shown by the total ozone evolution in the vortex during that winter from the SAOZ network compared to passive ozone simulations from the REPROBUS CTM, most of the total 39% total ozone depletion occurred after mid-February at a rate of near 0.8% /day when relatively low temperatures were still present in the Arctic. The evolution of ozone depletion is shown to fully match that of the cumulative area of temperatures below the chlorine activation threshold weighted by vortex sunlight illumination, assuming, as shown by Drlda and Mueller (2010), that chlorine activation occurs at 195 K at the 475 K level. However, if instead, the total integrated backscatter for combined liquid aerosols/PSCs inside the vortex reported by CALIPSO or the cumulated PSC surface at 191 K aligned to STS threshold are used, PSCs are seen to disappear in early March, that is three weeks before the end of ozone depletion. The suggestion is thus that chlorine activation takes place at temperature significantly warmer than that of NAT or STS PSC formation, on binary aerosol, still present and accounted for in the integrated backscatter, but of smaller surface area. The same analyses applied to all past winters since 1994 confirms the ozone depletion at relatively warm temperature in the absence of PSC. The mechanism involved is explored by a variety of model simulations, including or not, liquid binary aerosols, NAT and STS.

  19. Huntington's disease: effect of cysteamine, a somatostatin-depleting agent.

    PubMed

    Shults, C; Steardo, L; Barone, P; Mohr, E; Juncos, J; Serrati, C; Fedio, P; Tamminga, C A; Chase, T N

    1986-08-01

    Somatostatin levels in the basal ganglia are elevated in Huntington's disease. A controlled therapeutic trial of the somatostatin-depleting agent, cysteamine, was therefore conducted in five patients, including one with the rigid-akinetic form. Maximum tolerated dosage for 2 weeks produced no consistent change in extrapyramidal or dementia scores. Somatostatin concentrations were not significantly altered in plasma or CSF. Growth hormone levels, on the other hand, more than doubled, suggesting a functionally significant decrease in central somatostatin levels. PMID:2874527

  20. Mechanisms of enhanced taurine release under Ca2+ depletion.

    PubMed

    Molchanova, Svetlana M; Oja, Simo S; Saransaari, Pirjo

    2005-10-01

    The sulfur-containing amino acid taurine is an inhibitory neuromodulator in the brain of mammals, as well as a key substance in the regulation of cell volumes. The effect of Ca(2+) on extracellular taurine concentrations is of special interest in the context of the regulatory mechanisms of taurine release. The aim of this study was to characterize the basal release of taurine in Ca(2+)-free medium using in vivo microdialysis of the striatum of anesthetized rats. Perfusion of Ca(2+)-free medium via a microdialysis probe evoked a sustained release of taurine (up to 180 % compared to the basal levels). The Ca(2+) chelator EGTA (1mM) potentiated Ca(2+) depletion-evoked taurine release. The substitution of CaCl(2) by choline chloride did not alter the observed effect. Ca(2+)-free solution did not significantly evoke release of taurine from tissue loaded with the competitive inhibitor of taurine transporter guanidinoethanesulfonate (1mM), suggesting that in Ca(2+) depletion taurine is released by the transporter operating in the outward direction. The volume-sensitive chloride channel blocker diisothiocyanostilbene-2,2'-disulfonate (1mM) did not attenuate the taurine release evoked by Ca(2+) depletion. The non-specific blocker of voltage-sensitive Ca(2+) channels NiCl(2) (0.65 mM) enhanced taurine release in the presence of Ca(2+). CdCl(2) (0.25 mM) had no effect under these conditions. However, both CdCl(2) and NiCl(2) attenuated the effect of Ca(2+)-free medium on the release of taurine. The data obtained imply the involvement of both decreased influx of Ca(2+) and increased non-specific influx of Na(+) through voltage-sensitive calcium channels in the regulation of transporter-mediated taurine release in Ca(2+) depletion. PMID:15982785

  1. Gamma-ray line intensities for depleted uranium

    SciTech Connect

    Moss, C.E.

    1985-01-01

    Measurements of the gamma-ray line intensities from depleted uranium allowed us to determine which of two conflicting previous experiments was correct. For the 1001-keV line we obtain a branching ratio of 0.834 +- 0.007, in good agreement with one of the previous experiments. A table compares our intensities for several lines with those obtained in previous experiments. 5 refs., 2 figs., 1 tab.

  2. Response: Depletion and degradation are not the same

    SciTech Connect

    Vincent, J.R. )

    1993-04-01

    This article responses to the Case against Environmental Taxes for Sustainable Forestry. The author points out that in the previous article the implications of continuity of ownership and associate responsibilities are obscured by not clearly distinguishing timber-related depletion costs from nontimber environmental costs. Because the environmental effects of tropical logging are externalities, some type of public policy is neccessary to ensure that private actions coincide with socially optimal behavior. Environmental taxes may not be the only policy action available though.

  3. Chronic sodium depletion increases myocardial calcium content in normotensive rats.

    PubMed

    Rossi, G; Bond, M; Fouad-Tarazi, F M

    1989-03-01

    Increased myocardial contractility was found in the perfused heart isolated from sodium depleted Sprague-Dawley rats. Previously, it was reported that in vitro exposure of different cardiac preparations to low Na+ buffers was associated with both an increased contractility and an increased Ca2+ content in the cells. Therefore, this study was designed to examine increases in ventricular Ca2+ content in the hearts of chronically sodium depleted rats. Two groups of 12-week-old Sprague-Dawley rats were studied. One group (n = 5) received furosemide (5 mg/kg/day IP for 4 days), a low Na+ diet and distilled drinking water for 6 weeks (low sodium plus diuretics group = LSD). The other group (n = 5) received the same low Na+ diet, but 0.5% NaCl was supplemented in drinking water (regular sodium group = RS). Body weight and blood pressure were measured weekly during the dietary period in all rats. At the end of the 6 weeks, heart weight as well as water and electrolyte contents of the heart were measured in all animals. Results showed that both body weight and heart weight were significantly lower in LSD than in RS. Moreover, ventricular Na+ content was reduced while ventricular Ca2+ content was doubled in LSD compared to RS (8.2 +/- 0.2 units vs. 9.2 +/- 0.3 units, p less than .05 and 0.45 +/- 0.13 units vs. 0.23 +/- 0.01 units, p less than .01, respectively). We conclude that in vivo sodium depletion induces an increase in ventricular calcium content; this increased myocardial calcium may be related to the increased in vitro cardiac contractility observed after chronic in vivo sodium depletion, but its distribution between intracellular and extracellular compartments needs to be determined. PMID:2923136

  4. Depletion-induced structure and dynamics in bimodal colloidal suspensions.

    SciTech Connect

    Sikorski, M.; Sandy, A. R.; Narayanan, S.

    2011-05-03

    Combined small angle x-ray scattering and x-ray photon correlation spectroscopy studies of moderately concentrated bimodal hard-sphere colloidal suspensions in the fluid phase show that depletion-induced demixing introduces spatially heterogeneous dynamics with two distinct time scales. The adhesive nature, as well as the mobility, of the large particles is determined by the level of interaction within the monomodal domains. This interaction is driven by osmotic forces, which are governed by the relative concentration of the constituents.

  5. A search for relativistic electron induced stratospheric ozone depletion

    NASA Technical Reports Server (NTRS)

    Aikin, Arthur C.

    1994-01-01

    Possible ozone changes at 1 mb associated with the time variation and precipitation of relativistic electrons are investigated by examining the NIMBUS 7 SBUV ozone data set and corresponding temperatures derived from NMC data. No ozone depletion was observed in high-latitude summer when temperature fluctuations are small. In winter more variation in ozone occurs, but large temperature changes make it difficult to identify specific ozone decreases as being the result of relativistic electron precipitation.

  6. 1,2,3-D Diffusion Depletion Multi-Group

    Energy Science and Technology Software Center (ESTSC)

    1992-04-20

    CITATION is designed to solve problems using the finite difference representation of neutron diffusion theory, treating up to three space dimensions with arbitrary group to group scattering. X-y-z, theta-r-z, hexagonal z, and triagonal z geometries may be treated. Depletion problems may be solved and fuel managed for multi-cycle analysis. Extensive first order perturbation results may be obtained given microscopic data and nuclide concentrations. Statics problems may be solved and perturbation results obtained with microscopic data.

  7. Macrophage depletion ameliorates nephritis induced by pathogenic antibodies.

    PubMed

    Chalmers, Samantha A; Chitu, Violeta; Herlitz, Leal C; Sahu, Ranjit; Stanley, E Richard; Putterman, Chaim

    2015-02-01

    Kidney involvement affects 40-60% of patients with lupus, and is responsible for significant morbidity and mortality. Using depletion approaches, several studies have suggested that macrophages may play a key role in the pathogenesis of lupus nephritis. However, "off target" effects of macrophage depletion, such as altered hematopoiesis or enhanced autoantibody production, impeded the determination of a conclusive relationship. In this study, we investigated the role of macrophages in mice receiving rabbit anti-glomerular antibodies, or nephrotoxic serum (NTS), an experimental model which closely mimics the immune complex mediated disease seen in murine and human lupus nephritis. GW2580, a selective inhibitor of the colony stimulating factor-1 (CSF-1) receptor kinase, was used for macrophage depletion. We found that GW2580-treated, NTS challenged mice did not develop the increased levels of proteinuria, serum creatinine, and BUN seen in control-treated, NTS challenged mice. NTS challenged mice exhibited significantly increased kidney expression of inflammatory cytokines including RANTES, IP-10, VCAM-1 and iNOS, whereas GW2580-treated mice were protected from the robust expression of these inflammatory cytokines that are associated with lupus nephritis. Quantification of macrophage related gene expression, flow cytometry analysis of kidney single cell suspensions, and immunofluorescence staining confirmed the depletion of macrophages in GW2580-treated mice, specifically within renal glomeruli. Our results strongly implicate a specific and necessary role for macrophages in the development of immune glomerulonephritis mediated by pathogenic antibodies, and support the development of macrophage targeting approaches for the treatment of lupus nephritis. PMID:25554644

  8. Safety evaluation for packaging (onsite) depleted uranium waste boxes

    SciTech Connect

    McCormick, W.A.

    1997-08-27

    This safety evaluation for packaging (SEP) allows the one-time shipment of ten metal boxes and one wooden box containing depleted uranium material from the Fast Flux Test Facility to the burial grounds in the 200 West Area for disposal. This SEP provides the analyses and operational controls necessary to demonstrate that the shipment will be safe for the onsite worker and the public.

  9. Heterogeneous reactions important in atmospheric ozone depletion: a theoretical perspective.

    PubMed

    Bianco, Roberto; Hynes, James T

    2006-02-01

    Theoretical studies of the mechanisms of several heterogeneous reactions involving ClONO(2), H(2)O, HCl, HBr, and H(2)SO(4) important in atmospheric ozone depletion are described, focused primarily on reactions on aqueous aerosol surfaces. Among the insights obtained is the active chemical participation of the surface water molecules in several of these reactions. The general methodology adopted allows reduction of these complex chemical problems to meaningful model systems amenable to quantum chemical calculations. PMID:16489736

  10. Spatial Characteristics of Plasma Depletion Layer using Multiple Spacecraft Observations

    NASA Astrophysics Data System (ADS)

    Türk Katircioglu, Filiz; Angelopoulos, V.; Sibeck, David; Kaymaz, Zerefsan

    2016-07-01

    The plasma depletion layer (PDL) is observed occasionally with Themis B and Themis D spacecraft on dayside magnetosheath between the years 2007-2009. PDL characterizes itself with decreased density and increased magnetic field and its presence depends on the IMF and solar wind conditions. It is mostly known to occur under northward IMF conditions. When the IMF and solar wind conditions favor, the layer occurs just in front of the magnetopause. From the single satellite observations, it is very hard to determine the region because of the difficulties arising from the interaction between the magnetosheath field and flow and Earth's dipole field at the magnetopause boundary under certain IMF and solar wind plasma conditions. In this study, we use multiple Themis observations to understand the spatial differentiation of plasma depletion layer. The high resolution plasma and magnetic field data from multiple Themis spacecraft allow us to determine the spatial extend of the depletion layer and help us to understand its spatial variations. Initial results show that PDL is clearly determined at the subsolar region of the magnetopause with a sharp increase in magnetic field within a narrow zone. We also detect PDL along the flanks of the magnetopause as well as above the equatorial plane. In this presentation, we will show examples of PDL from different regions of the magnetopause boundary and discuss their occurrence and formation mechanisms.

  11. Alignment of gold nanorods by angular photothermal depletion

    SciTech Connect

    Taylor, Adam B.; Chow, Timothy T. Y.; Chon, James W. M.

    2014-02-24

    In this paper, we demonstrate that a high degree of alignment can be imposed upon randomly oriented gold nanorod films by angular photothermal depletion with linearly polarized laser irradiation. The photothermal reshaping of gold nanorods is observed to follow quadratic melting model rather than the threshold melting model, which distorts the angular and spectral hole created on 2D distribution map of nanorods to be an open crater shape. We have accounted these observations to the alignment procedures and demonstrated good agreement between experiment and simulations. The use of multiple laser depletion wavelengths allowed alignment criteria over a large range of aspect ratios, achieving 80% of the rods in the target angular range. We extend the technique to demonstrate post-alignment in a multilayer of randomly oriented gold nanorod films, with arbitrary control of alignment shown across the layers. Photothermal angular depletion alignment of gold nanorods is a simple, promising post-alignment method for creating future 3D or multilayer plasmonic nanorod based devices and structures.

  12. Ionospheric heating, upwelling, and depletions in auroral current systems

    NASA Astrophysics Data System (ADS)

    Zettergren, M. D.; Semeter, J. L.

    2010-12-01

    This research investigates aspects of ionospheric dynamics relevant to magnetosphere-ionosphere coupling in auroral arc current systems. Auroral electric fields and particle precipitation deposit energy in the ionosphere, often resulting in enhanced ion or electron temperatures. This heating has a wide variety of consequences for the ionosphere. High ion temperatures alter chemical balance in the lower F-region, resulting in conversion to a molecular ion plasma, faster recombination, and plasma depletions. Pressure enhancements resulting from both ion and electron heating are capable of generating intense ion upflows. Ion upflow and depletion processes redistribute and structure the auroral plasma in ways that are likely of consequence to wave coupling of the magnetosphere and ionosphere. These implications are examined through the use of a fluid-kinetic model of the auroral ionosphere and new incoherent scatter radar data analysis techniques. Results indicate that enhanced recombination of molecular ions in auroral downward current regions may work in concert with well-known electrodynamic depletion processes, in the F-region ionosphere. Furthermore, ionospheric upflows in auroral upward and downward current regions may be quite different in terms of intensity and types of upflowing ions.

  13. [Biomedical and economic consequences of stratosphere ozone depletion].

    PubMed

    Strzhizhovskiĭ, A D

    1998-01-01

    Information on possible human health-changes associated with stratosphere ozone depletion and amplification factor (% increase of the stick rate by 1% decrease of ozone) values for acute (erythema, keratitis, cataract, immunosuppression) and chronic (skin cancer, cataract) effects of natural UV-radiation was analysed. Amplification factor (AF) values for acute UV-effects increase with degree of ozone depletion. For degrees less than 12.5% they are independent of latitude and equal to 1.9 for erythema, 1.3-1.5 for keratitis, 1.7-2.3 for cataract and 0.9-1.1 for immunosuppression. AF values for incidence of non-melanoma skin cancer are independent of age, higher in males than females, and higher for squamous cell carcinoma, than for basal cell carcinoma. Their optimal estimations for whites equal to 2.7 for basal cell and 4.6 for squamous cell carcinoma. AF values for incidence of cutaneous malignant melanoma range between 1 and 2, for melanoma mortality--between 0.3 and 2. AF values for incidence of cataract range between 0.3 and 1.2 with optimal estimations between 0.6 and 0.8. Prognosis of non-melanoma skin cancer and cataract incidences, melanoma mortality and economic loss for different scenarios of stratosphere ozone depletion are presented. PMID:9633627

  14. Frost Induces Respiration and Accelerates Carbon Depletion in Trees.

    PubMed

    Sperling, Or; Earles, J Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A

    2015-01-01

    Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0 °C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq.) cm(-3) yr(-1) on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics. PMID:26629819

  15. Structurally Resolved Abundances and Depletions in the Rho OPH Cloud

    NASA Astrophysics Data System (ADS)

    Seab, C.

    1995-07-01

    The mechanism that determines the pattern of depletion ofelements in the interstellar medium has been a problem for along time. It is clear that some of the most refractoryelements such as Si, Fe, and Mg, are heavily depleted onto theinterstellar grains. On the other hand, some elements such asS and Zn are normally either undepleted or very lightlydepleted. The difference between the two cases is notunderstood. We propose to address this question with adetailed study of the depletion patterns in the Rho Ophiuchicloud. This study is strongly based on a combination of thecapabilities of two modern instruments: the GHRS for high-resolution UV data, and the Ultra High Resolution Facility(UHRF) of the AAT. This instrument has been used to obtain NaI line profiles in the Rho Oph cloud with a resolution ofR=1,000,000. The combination of these two types of data willbe used to resolve the velocity structure of the elementdepletions in the cloud.

  16. Accounting for Depletion of Oil and Gas Resources in Malaysia

    SciTech Connect

    Othman, Jamal Jafari, Yaghoob

    2012-12-15

    Since oil and gas are non-renewable resources, it is important to identify the extent to which they have been depleted. Such information will contribute to the formulation and evaluation of appropriate sustainable development policies. This paper provides an assessment of the changes in the availability of oil and gas resources in Malaysia by first compiling the physical balance sheet for the period 2000-2007, and then assessing the monetary balance sheets for the said resource by using the Net Present Value method. Our findings show serious reduction in the value of oil reserves from 2001 to 2005, due to changes in crude oil prices, and thereafter the depletion rates decreased. In the context of sustainable development planning, albeit in the weak sustainability sense, it will be important to ascertain if sufficient reinvestments of the estimated resource rents in related or alternative capitals are being attempted by Malaysia. For the study period, the cumulative resource rents were to the tune of RM61 billion. Through a depletion or resource rents policy, the estimated quantum may guide the identification of a reinvestment threshold (after considering needed capital investment for future development of the industry) in light of ensuring the future productive capacity of the economy at the time when the resource is exhausted.

  17. Ionization and elemental depletion in the interstellar medium

    NASA Astrophysics Data System (ADS)

    Vladilo, G.; Centurion, M.

    1990-07-01

    The behavior of the elemental depletions in the ISM along lines of sight with a very low value of the average hydrogen density is examined. A simple model in the frame of the McKee-Ostriker (1977) theory has been used to estimate the line-of-sight filling factors as a function of n-bar for those interstellar phases in which a significant degree of ionization is expected. The results show that a substantial fraction of ionized gas outside classical H II regions may well be present along the line of sight when n-bar is less than about 0.1/cu cm. If this effect is neglected, the chemical abundances relative to hydrogen can be overestimated up to 0.5 dex in logarithm, and the depletions underestimated by the same amount. A recent IUE survey of interstellar abundances has been reanalyzed, and it is found that for all the elements investigated the slope of the correlation D(app)-log n-bar is steeper in the low-density range. This disagrees with recent models for elemental depletions.

  18. Inhomogeneous depletion of oxygen ions in metal oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Vykhodets, Vladimir B.; Jarvis, Emily A. A.; Kurennykh, Tatiana E.; Beketov, Igor V.; Obukhov, Sviatoslav I.; Samatov, Oleg M.; Medvedev, Anatoly I.; Davletshin, Andrey E.; Whyte, Travis H.

    2016-02-01

    Zirconia and yttria stabilized zirconia (YSZ) have multiple uses, including catalysis, fuel cells, dental applications, and thermal coatings. We employ nuclear reaction analysis to determine elemental composition of YSZ nanoparticles synthesized by laser evaporation including 18O studies to distinguish between oxide and adsorbed oxygen content as a function of surface area. We see dramatic deviation from stoichiometry that can be traced to loss of oxygen from the oxide near the surface of these nanopowders. Density functional calculations are coupled with these experimental studies to explore the electronic structure of nonstoichiometric surfaces achieved through depletion of oxygen. Our results show oxygen-depleted surfaces present under oxygen potentials where stoichiometric, oxygen-terminated surfaces would be favored thermodynamically for crystalline systems. Oxygen depletion at nanopowder surfaces can create effective two-dimensional surface metallic states while maintaining stoichiometry in the underlying nanoparticle core. This insight into nanopowder surfaces applies to dissimilar oxides of aluminum and zirconium indicating synthesis conditions may be more influential than the inherent oxide properties and displaying need for distinct models for nanopowders of these important engineering materials where surface chemistry dominates performance.

  19. Follicle Depletion Provides a Permissive Environment for Ovarian Carcinogenesis.

    PubMed

    Wang, Ying; Cai, Kathy Qi; Smith, Elizabeth R; Yeasky, Toni M; Moore, Robert; Ganjei-Azar, Parvin; Klein-Szanto, Andres J; Godwin, Andrew K; Hamilton, Thomas C; Xu, Xiang-Xi

    2016-09-15

    We modeled the etiology of postmenopausal biology on ovarian cancer risk using germ cell-deficient white-spotting variant (Wv) mice, incorporating oncogenic mutations. Ovarian cancer incidence is highest in peri- and postmenopausal women, and epidemiological studies have established the impact of reproductive factors on ovarian cancer risk. Menopause as a result of ovarian follicle depletion is thought to contribute to higher cancer risk. As a consequence of follicle depletion, female Wv mice develop ovarian tubular adenomas, a benign epithelial tumor corresponding to surface epithelial invaginations and papillomatosis frequently found in postmenopausal human ovaries. Lineage tracing using MISR2-Cre indicated that the tubular adenomas that developed in Wv mice were largely derived from the MISR2 lineage, which marked only a fraction of ovarian surface and oviduct epithelial cells in wild-type tissues. Deletion of p27, either heterozygous or homozygous, was able to convert the benign tubular adenomas into more proliferative tumors. Restricted deletion of p53 in Wv/Wv mice by either intrabursal injection of adenoviral Cre or inclusion of the MISR2-Cre transgene also resulted in augmented tumor growth. This finding suggests that follicle depletion provides a permissive ovarian environment for oncogenic transformation of epithelial cells, presenting a mechanism for the increased ovarian cancer risk in postmenopausal women. PMID:27354067

  20. Frost Induces Respiration and Accelerates Carbon Depletion in Trees

    PubMed Central

    Sperling, Or; Earles, J. Mason; Secchi, Francesca; Godfrey, Jessie; Zwieniecki, Maciej A.

    2015-01-01

    Cellular respiration depletes stored carbohydrates during extended periods of limited photosynthesis, e.g. winter dormancy or drought. As respiration rate is largely a function of temperature, the thermal conditions during such periods may affect non-structural carbohydrate (NSC) availability and, ultimately, recovery. Here, we surveyed stem responses to temperature changes in 15 woody species. For two species with divergent respirational response to frost, P. integerrima and P. trichocarpa, we also examined corresponding changes in NSC levels. Finally, we simulated respiration-induced NSC depletion using historical temperature data for the western US. We report a novel finding that tree stems significantly increase respiration in response to near freezing temperatures. We observed this excess respiration in 13 of 15 species, deviating 10% to 170% over values predicted by the Arrhenius equation. Excess respiration persisted at temperatures above 0°C during warming and reoccurred over multiple frost-warming cycles. A large adjustment of NSCs accompanied excess respiration in P. integerrima, whereas P. trichocarpa neither excessively respired nor adjusted NSCs. Over the course of the years included in our model, frost-induced respiration accelerated stem NSC consumption by 8.4 mg (glucose eq.) cm-3 yr-1 on average in the western US, a level of depletion that may continue to significantly affect spring NSC availability. This novel finding revises the current paradigm of low temperature respiration kinetics. PMID:26629819

  1. Combinatorial neural codes from a mathematical coding theory perspective.

    PubMed

    Curto, Carina; Itskov, Vladimir; Morrison, Katherine; Roth, Zachary; Walker, Judy L

    2013-07-01

    Shannon's seminal 1948 work gave rise to two distinct areas of research: information theory and mathematical coding theory. While information theory has had a strong influence on theoretical neuroscience, ideas from mathematical coding theory have received considerably less attention. Here we take a new look at combinatorial neural codes from a mathematical coding theory perspective, examining the error correction capabilities of familiar receptive field codes (RF codes). We find, perhaps surprisingly, that the high levels of redundancy present in these codes do not support accurate error correction, although the error-correcting performance of receptive field codes catches up to that of random comparison codes when a small tolerance to error is introduced. However, receptive field codes are good at reflecting distances between represented stimuli, while the random comparison codes are not. We suggest that a compromise in error-correcting capability may be a necessary price to pay for a neural code whose structure serves not only error correction, but must also reflect relationships between stimuli. PMID:23724797

  2. On lossless coding for HEVC

    NASA Astrophysics Data System (ADS)

    Gao, Wen; Jiang, Minqiang; Yu, Haoping

    2013-02-01

    In this paper, we first review the lossless coding mode in the version 1 of the HEVC standard that has recently finalized. We then provide a performance comparison between the lossless coding mode in the HEVC and MPEG-AVC/H.264 standards and show that the HEVC lossless coding has limited coding efficiency. To improve the performance of the lossless coding mode, several new coding tools that were contributed to JCT-VC but not adopted in version 1 of HEVC standard are introduced. In particular, we discuss sample based intra prediction and coding of residual coefficients in more detail. At the end, we briefly address a new class of coding tools, i.e., a dictionary-based coder, that is efficient in encoding screen content including graphics and text.

  3. Geologic Sequestration of CO2 in a Depleted Oil Reservoir: A Field Demonstration

    NASA Astrophysics Data System (ADS)

    Westrich, H. R.; Zhang, D.; Grigg, R. B.

    2002-12-01

    Carbon dioxide (CO2) sequestration in geologic formations is the most direct carbon management strategy for long-term removal of anthropogenic CO2 from the atmosphere, and is likely to be needed for continuation of the US fossil fuel-based economy and high standard of living. Subsurface injection of CO2 into depleted oil reservoirs is a carbon sequestration strategy that might prove to be both cost effective and environmentally safe. However, there are significant R&D gaps that need to be addressed prior to sequestration of CO2 in depleted oil reservoirs, including the need of coupled physicochemical processes involving CO2, water, oil and reservoir rock, better estimates of the capacity of reservoir for long-term sequestration and ultimate fate of injected CO2, and improved geophysical monitoring technologies for accurately determining the presence and location of injected CO2. Our project is part of the DOE Carbon Sequestration program and it is directed at predicting and monitoring the migration and ultimate fate of CO2 after injection in a depleted oil reservoir. We utilize computer simulations of multiphase oil-brine-CO2 flow in the reservoir, laboratory measurements of geochemical brine-rock reactions, and geophysical surveys to monitor CO2 plume migration after injection. A principal component of this project is characterization and validation of predicted CO2 migration and fate through a field demonstration experiment. The reservoir under investigation is part of the West Pearl Queen field in southeastern New Mexico. Geologic modeling and numerical flow simulations (ECLIPSE code) have been used to study the feasibility of injection, and these techniques were used to help in designing geophysical monitoring studies to track the injected plume. Long-term static brine-rock reactions and short-term brine-CO2-oil flow through tests were performed to better understand the likely geochemical reactions that might be influence CO2 sequestration or injection. Results

  4. Ozone depletion and climate change: impacts on UV radiation.

    PubMed

    McKenzie, R L; Aucamp, P J; Bais, A F; Björn, L O; Ilyas, M; Madronich, S

    2011-02-01

    The Montreal Protocol is working, but it will take several decades for ozone to return to 1980 levels. The atmospheric concentrations of ozone depleting substances are decreasing, and ozone column amounts are no longer decreasing. Mid-latitude ozone is expected to return to 1980 levels before mid-century, slightly earlier than predicted previously. However, the recovery rate will be slower at high latitudes. Springtime ozone depletion is expected to continue to occur at polar latitudes, especially in Antarctica, in the next few decades. Because of the success of the Protocol, increases in UV-B radiation have been small outside regions affected by the Antarctic ozone hole, and have been difficult to detect. There is a large variability in UV-B radiation due to factors other than ozone, such as clouds and aerosols. There are few long-term measurements available to confirm the increases that would have occurred as a result of ozone depletion. At mid-latitudes UV-B irradiances are currently only slightly greater than in 1980 (increases less than ~5%), but increases have been substantial at high and polar latitudes where ozone depletion has been larger. Without the Montreal Protocol, peak values of sunburning UV radiation could have been tripled by 2065 at mid-northern latitudes. This would have had serious consequences for the environment and for human health. There are strong interactions between ozone depletion and changes in climate induced by increasing greenhouse gases (GHGs). Ozone depletion affects climate, and climate change affects ozone. The successful implementation of the Montreal Protocol has had a marked effect on climate change. The calculated reduction in radiative forcing due to the phase-out of chlorofluorocarbons (CFCs) far exceeds that from the measures taken under the Kyoto protocol for the reduction of GHGs. Thus the phase-out of CFCs is currently tending to counteract the increases in surface temperature due to increased GHGs. The amount of

  5. Code System for Reactor Physics and Fuel Cycle Simulation.

    Energy Science and Technology Software Center (ESTSC)

    1999-04-21

    Version 00 VSOP94 (Very Superior Old Programs) is a system of codes linked together for the simulation of reactor life histories. It comprises neutron cross section libraries and processing routines, repeated neutron spectrum evaluation, 2-D diffusion calculation based on neutron flux synthesis with depletion and shut-down features, in-core and out-of-pile fuel management, fuel cycle cost analysis, and thermal hydraulics (at present restricted to Pebble Bed HTRs). Various techniques have been employed to accelerate the iterativemore » processes and to optimize the internal data transfer. The code system has been used extensively for comparison studies of reactors, their fuel cycles, and related detailed features. In addition to its use in research and development work for the High Temperature Reactor, the system has been applied successfully to Light Water and Heavy Water Reactors.« less

  6. Code System for Reactor Physics and Fuel Cycle Simulation.

    SciTech Connect

    TEUCHERT, E.

    1999-04-21

    Version 00 VSOP94 (Very Superior Old Programs) is a system of codes linked together for the simulation of reactor life histories. It comprises neutron cross section libraries and processing routines, repeated neutron spectrum evaluation, 2-D diffusion calculation based on neutron flux synthesis with depletion and shut-down features, in-core and out-of-pile fuel management, fuel cycle cost analysis, and thermal hydraulics (at present restricted to Pebble Bed HTRs). Various techniques have been employed to accelerate the iterative processes and to optimize the internal data transfer. The code system has been used extensively for comparison studies of reactors, their fuel cycles, and related detailed features. In addition to its use in research and development work for the High Temperature Reactor, the system has been applied successfully to Light Water and Heavy Water Reactors.

  7. Ly6G-mediated depletion of neutrophils is dependent on macrophages.

    PubMed

    Bruhn, Kevin W; Dekitani, Ken; Nielsen, Travis B; Pantapalangkoor, Paul; Spellberg, Brad

    2016-01-01

    Antibody-mediated depletion of neutrophils is commonly used to study neutropenia. However, the mechanisms by which antibodies deplete neutrophils have not been well defined. We noticed that mice deficient in complement and macrophages had blunted neutrophil depletion in response to anti-Ly6G monoclonal antibody (MAb) treatment. In vitro, exposure of murine neutrophils to anti-Ly6G MAb in the presence of plasma did not result in significant depletion of cells, either in the presence or absence of complement. In vivo, anti-Ly6G-mediated neutrophil depletion was abrogated following macrophage depletion, but not complement depletion, indicating a requirement for macrophages to induce neutropenia by this method. These results inform the use and limitations of anti-Ly6G antibody as an experimental tool for depleting neutrophils in various immunological settings. PMID:26870635

  8. Noiseless Coding Of Magnetometer Signals

    NASA Technical Reports Server (NTRS)

    Rice, Robert F.; Lee, Jun-Ji

    1989-01-01

    Report discusses application of noiseless data-compression coding to digitized readings of spaceborne magnetometers for transmission back to Earth. Objective of such coding to increase efficiency by decreasing rate of transmission without sacrificing integrity of data. Adaptive coding compresses data by factors ranging from 2 to 6.

  9. Energy Codes and Standards: Facilities

    SciTech Connect

    Bartlett, Rosemarie; Halverson, Mark A.; Shankle, Diana L.

    2007-01-01

    Energy codes and standards play a vital role in the marketplace by setting minimum requirements for energy-efficient design and construction. They outline uniform requirements for new buildings as well as additions and renovations. This article covers basic knowledge of codes and standards; development processes of each; adoption, implementation, and enforcement of energy codes and standards; and voluntary energy efficiency programs.

  10. Coding Issues in Grounded Theory

    ERIC Educational Resources Information Center

    Moghaddam, Alireza

    2006-01-01

    This paper discusses grounded theory as one of the qualitative research designs. It describes how grounded theory generates from data. Three phases of grounded theory--open coding, axial coding, and selective coding--are discussed, along with some of the issues which are the source of debate among grounded theorists, especially between its…

  11. Authorship Attribution of Source Code

    ERIC Educational Resources Information Center

    Tennyson, Matthew F.

    2013-01-01

    Authorship attribution of source code is the task of deciding who wrote a program, given its source code. Applications include software forensics, plagiarism detection, and determining software ownership. A number of methods for the authorship attribution of source code have been presented in the past. A review of those existing methods is…

  12. Ethical Codes in the Professions.

    ERIC Educational Resources Information Center

    Schmeiser, Cynthia B.

    1992-01-01

    Whether the measurement profession should consider developing and adopting a code of professional conduct is explored after a brief review of existing references to standards of conduct and a review of other professional codes. Issues include the need for a code of ethics, its usefulness, and its enforcement. (SLD)

  13. Finite Element Analysis Code

    Energy Science and Technology Software Center (ESTSC)

    2005-05-07

    CONEX is a code for joining sequentially in time multiple exodusll database files which all represent the same base mesh topology and geometry. It is used to create a single results or restart file from multiple results or restart files which typically arise as the result of multiple restarted analyses. CONEX is used to postprocess the results from a series of finite element analyses. It can join sequentially the data from multiple results databases intomore » a single database which makes it easier to postprocess the results data.« less

  14. Finite Element Analysis Code

    Energy Science and Technology Software Center (ESTSC)

    2005-06-26

    Exotxt is an analysis code that reads finite element results data stored in an exodusII file and generates a file in a structured text format. The text file can be edited or modified via a number of text formatting tools. Exotxt is used by analysis to translate data from the binary exodusII format into a structured text format which can then be edited or modified and then either translated back to exodusII format or tomore » another format.« less

  15. Low Density Parity Check Codes: Bandwidth Efficient Channel Coding

    NASA Technical Reports Server (NTRS)

    Fong, Wai; Lin, Shu; Maki, Gary; Yeh, Pen-Shu

    2003-01-01

    Low Density Parity Check (LDPC) Codes provide near-Shannon Capacity performance for NASA Missions. These codes have high coding rates R=0.82 and 0.875 with moderate code lengths, n=4096 and 8176. Their decoders have inherently parallel structures which allows for high-speed implementation. Two codes based on Euclidean Geometry (EG) were selected for flight ASIC implementation. These codes are cyclic and quasi-cyclic in nature and therefore have a simple encoder structure. This results in power and size benefits. These codes also have a large minimum distance as much as d,,, = 65 giving them powerful error correcting capabilities and error floors less than lo- BER. This paper will present development of the LDPC flight encoder and decoder, its applications and status.

  16. New quantum codes constructed from quaternary BCH codes

    NASA Astrophysics Data System (ADS)

    Xu, Gen; Li, Ruihu; Guo, Luobin; Ma, Yuena

    2016-07-01

    In this paper, we firstly study construction of new quantum error-correcting codes (QECCs) from three classes of quaternary imprimitive BCH codes. As a result, the improved maximal designed distance of these narrow-sense imprimitive Hermitian dual-containing quaternary BCH codes are determined to be much larger than the result given according to Aly et al. (IEEE Trans Inf Theory 53:1183-1188, 2007) for each different code length. Thus, families of new QECCs are newly obtained, and the constructed QECCs have larger distance than those in the previous literature. Secondly, we apply a combinatorial construction to the imprimitive BCH codes with their corresponding primitive counterpart and construct many new linear quantum codes with good parameters, some of which have parameters exceeding the finite Gilbert-Varshamov bound for linear quantum codes.

  17. Structured error recovery for code-word-stabilized quantum codes

    SciTech Connect

    Li Yunfan; Dumer, Ilya; Grassl, Markus; Pryadko, Leonid P.

    2010-05-15

    Code-word-stabilized (CWS) codes are, in general, nonadditive quantum codes that can correct errors by an exhaustive search of different error patterns, similar to the way that we decode classical nonlinear codes. For an n-qubit quantum code correcting errors on up to t qubits, this brute-force approach consecutively tests different errors of weight t or less and employs a separate n-qubit measurement in each test. In this article, we suggest an error grouping technique that allows one to simultaneously test large groups of errors in a single measurement. This structured error recovery technique exponentially reduces the number of measurements by about 3{sup t} times. While it still leaves exponentially many measurements for a generic CWS code, the technique is equivalent to syndrome-based recovery for the special case of additive CWS codes.

  18. Measuring Diagnoses: ICD Code Accuracy

    PubMed Central

    O'Malley, Kimberly J; Cook, Karon F; Price, Matt D; Wildes, Kimberly Raiford; Hurdle, John F; Ashton, Carol M

    2005-01-01

    Objective To examine potential sources of errors at each step of the described inpatient International Classification of Diseases (ICD) coding process. Data Sources/Study Setting The use of disease codes from the ICD has expanded from classifying morbidity and mortality information for statistical purposes to diverse sets of applications in research, health care policy, and health care finance. By describing a brief history of ICD coding, detailing the process for assigning codes, identifying where errors can be introduced into the process, and reviewing methods for examining code accuracy, we help code users more systematically evaluate code accuracy for their particular applications. Study Design/Methods We summarize the inpatient ICD diagnostic coding process from patient admission to diagnostic code assignment. We examine potential sources of errors at each step and offer code users a tool for systematically evaluating code accuracy. Principle Findings Main error sources along the “patient trajectory” include amount and quality of information at admission, communication among patients and providers, the clinician's knowledge and experience with the illness, and the clinician's attention to detail. Main error sources along the “paper trail” include variance in the electronic and written records, coder training and experience, facility quality-control efforts, and unintentional and intentional coder errors, such as misspecification, unbundling, and upcoding. Conclusions By clearly specifying the code assignment process and heightening their awareness of potential error sources, code users can better evaluate the applicability and limitations of codes for their particular situations. ICD codes can then be used in the most appropriate ways. PMID:16178999

  19. Genetic code for sine

    NASA Astrophysics Data System (ADS)

    Abdullah, Alyasa Gan; Wah, Yap Bee

    2015-02-01

    The computation of the approximate values of the trigonometric sines was discovered by Bhaskara I (c. 600-c.680), a seventh century Indian mathematician and is known as the Bjaskara's I's sine approximation formula. The formula is given in his treatise titled Mahabhaskariya. In the 14th century, Madhava of Sangamagrama, a Kerala mathematician astronomer constructed the table of trigonometric sines of various angles. Madhava's table gives the measure of angles in arcminutes, arcseconds and sixtieths of an arcsecond. The search for more accurate formulas led to the discovery of the power series expansion by Madhava of Sangamagrama (c.1350-c. 1425), the founder of the Kerala school of astronomy and mathematics. In 1715, the Taylor series was introduced by Brook Taylor an English mathematician. If the Taylor series is centered at zero, it is called a Maclaurin series, named after the Scottish mathematician Colin Maclaurin. Some of the important Maclaurin series expansions include trigonometric functions. This paper introduces the genetic code of the sine of an angle without using power series expansion. The genetic code using square root approach reveals the pattern in the signs (plus, minus) and sequence of numbers in the sine of an angle. The square root approach complements the Pythagoras method, provides a better understanding of calculating an angle and will be useful for teaching the concepts of angles in trigonometry.

  20. 26 CFR 1.611-1 - Allowance of deduction for depletion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Allowance of deduction for depletion. 1.611-1 Section 1.611-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.611-1 Allowance of deduction for depletion. (a) Depletion of mines, oil and gas...

  1. 48 CFR 211.271 - Elimination of use of class I ozone-depleting substances.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... class I ozone-depleting substances. 211.271 Section 211.271 Federal Acquisition Regulations System... Using and Maintaining Requirements Documents 211.271 Elimination of use of class I ozone-depleting substances. See subpart 223.8 for restrictions on contracting for ozone-depleting substances....

  2. 48 CFR 211.271 - Elimination of use of class I ozone-depleting substances.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... class I ozone-depleting substances. 211.271 Section 211.271 Federal Acquisition Regulations System... Using and Maintaining Requirements Documents 211.271 Elimination of use of class I ozone-depleting substances. See subpart 223.8 for restrictions on contracting for ozone-depleting substances....

  3. 48 CFR 211.271 - Elimination of use of class I ozone-depleting substances.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... class I ozone-depleting substances. 211.271 Section 211.271 Federal Acquisition Regulations System... Using and Maintaining Requirements Documents 211.271 Elimination of use of class I ozone-depleting substances. See subpart 223.8 for restrictions on contracting for ozone-depleting substances....

  4. 48 CFR 211.271 - Elimination of use of class I ozone-depleting substances.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... class I ozone-depleting substances. 211.271 Section 211.271 Federal Acquisition Regulations System... Using and Maintaining Requirements Documents 211.271 Elimination of use of class I ozone-depleting substances. See subpart 223.8 for restrictions on contracting for ozone-depleting substances....

  5. 48 CFR 211.271 - Elimination of use of class I ozone-depleting substances.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... class I ozone-depleting substances. 211.271 Section 211.271 Federal Acquisition Regulations System... Using and Maintaining Requirements Documents 211.271 Elimination of use of class I ozone-depleting substances. See subpart 223.8 for restrictions on contracting for ozone-depleting substances....

  6. 26 CFR 1.1502-44 - Percentage depletion for independent producers and royalty owners.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sum of the percentage depletion deductions for the taxable year for all oil or gas property owned by... an oil or gas property (other than a gas property with respect to which the depletion allowance for... the maximum allowable percentage depletion deduction among oil and gas properties. Thus, if, after...

  7. 26 CFR 1.1502-44 - Percentage depletion for independent producers and royalty owners.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sum of the percentage depletion deductions for the taxable year for all oil or gas property owned by... an oil or gas property (other than a gas property with respect to which the depletion allowance for... the maximum allowable percentage depletion deduction among oil and gas properties. Thus, if, after...

  8. 26 CFR 1.612-3 - Depletion; treatment of bonus and advanced royalty.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 7 2013-04-01 2013-04-01 false Depletion; treatment of bonus and advanced... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.612-3 Depletion; treatment... the payee as a cost depletion deduction in respect of the bonus an amount equal to that proportion...

  9. 26 CFR 1.612-3 - Depletion; treatment of bonus and advanced royalty.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 7 2014-04-01 2013-04-01 true Depletion; treatment of bonus and advanced... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.612-3 Depletion; treatment... the payee as a cost depletion deduction in respect of the bonus an amount equal to that proportion...

  10. 26 CFR 1.1502-44 - Percentage depletion for independent producers and royalty owners.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... sum of the percentage depletion deductions for the taxable year for all oil or gas property owned by... an oil or gas property (other than a gas property with respect to which the depletion allowance for... the maximum allowable percentage depletion deduction among oil and gas properties. Thus, if, after...

  11. 26 CFR 1.612-3 - Depletion; treatment of bonus and advanced royalty.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 7 2012-04-01 2012-04-01 false Depletion; treatment of bonus and advanced... (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.612-3 Depletion; treatment... the payee as a cost depletion deduction in respect of the bonus an amount equal to that proportion...

  12. 26 CFR 1.1502-44 - Percentage depletion for independent producers and royalty owners.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... sum of the percentage depletion deductions for the taxable year for all oil or gas property owned by... an oil or gas property (other than a gas property with respect to which the depletion allowance for... the maximum allowable percentage depletion deduction among oil and gas properties. Thus, if, after...

  13. 26 CFR 52.4681-1 - Taxes imposed with respect to ozone-depleting chemicals.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...)) for the calendar year in which the sale or use occurs; and (iii) The ozone-depletion factor... 26 Internal Revenue 17 2011-04-01 2011-04-01 false Taxes imposed with respect to ozone-depleting... to ozone-depleting chemicals. (a) Taxes imposed. Sections 4681 and 4682 impose the following...

  14. 26 CFR 52.4681-1 - Taxes imposed with respect to ozone-depleting chemicals.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...)) for the calendar year in which the sale or use occurs; and (iii) The ozone-depletion factor... 26 Internal Revenue 17 2010-04-01 2010-04-01 false Taxes imposed with respect to ozone-depleting... to ozone-depleting chemicals. (a) Taxes imposed. Sections 4681 and 4682 impose the following...

  15. 26 CFR 52.4681-1 - Taxes imposed with respect to ozone-depleting chemicals.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 17 2012-04-01 2012-04-01 false Taxes imposed with respect to ozone-depleting... to ozone-depleting chemicals. (a) Taxes imposed. Sections 4681 and 4682 impose the following taxes with respect to ozone-depleting chemicals (ODCs): (1) Tax on ODCs. Section 4681(a)(1) imposes a tax...

  16. 26 CFR 52.4681-1 - Taxes imposed with respect to ozone-depleting chemicals.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 17 2014-04-01 2014-04-01 false Taxes imposed with respect to ozone-depleting... to ozone-depleting chemicals. (a) Taxes imposed. Sections 4681 and 4682 impose the following taxes with respect to ozone-depleting chemicals (ODCs): (1) Tax on ODCs. Section 4681(a)(1) imposes a tax...

  17. 26 CFR 1.611-1 - Allowance of deduction for depletion.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 7 2011-04-01 2009-04-01 true Allowance of deduction for depletion. 1.611-1 Section 1.611-1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INCOME TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.611-1 Allowance of deduction for depletion. (a) Depletion of mines, oil and gas...

  18. 26 CFR 1.611-1 - Allowance of deduction for depletion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TAX (CONTINUED) INCOME TAXES (CONTINUED) Natural Resources § 1.611-1 Allowance of deduction for depletion. (a) Depletion of mines, oil and gas wells, other natural deposits, and timber—(1) In general... of the property. In the case of other exhaustible natural resources the allowance for depletion...

  19. Determinate-state convolutional codes

    NASA Technical Reports Server (NTRS)

    Collins, O.; Hizlan, M.

    1991-01-01

    A determinate state convolutional code is formed from a conventional convolutional code by pruning away some of the possible state transitions in the decoding trellis. The type of staged power transfer used in determinate state convolutional codes proves to be an extremely efficient way of enhancing the performance of a concatenated coding system. The decoder complexity is analyzed along with free distances of these new codes and extensive simulation results is provided of their performance at the low signal to noise ratios where a real communication system would operate. Concise, practical examples are provided.

  20. Coding for reliable satellite communications

    NASA Technical Reports Server (NTRS)

    Gaarder, N. T.; Lin, S.

    1986-01-01

    This research project was set up to study various kinds of coding techniques for error control in satellite and space communications for NASA Goddard Space Flight Center. During the project period, researchers investigated the following areas: (1) decoding of Reed-Solomon codes in terms of dual basis; (2) concatenated and cascaded error control coding schemes for satellite and space communications; (3) use of hybrid coding schemes (error correction and detection incorporated with retransmission) to improve system reliability and throughput in satellite communications; (4) good codes for simultaneous error correction and error detection, and (5) error control techniques for ring and star networks.

  1. Circular codes, symmetries and transformations.

    PubMed

    Fimmel, Elena; Giannerini, Simone; Gonzalez, Diego Luis; Strüngmann, Lutz

    2015-06-01

    Circular codes, putative remnants of primeval comma-free codes, have gained considerable attention in the last years. In fact they represent a second kind of genetic code potentially involved in detecting and maintaining the normal reading frame in protein coding sequences. The discovering of an universal code across species suggested many theoretical and experimental questions. However, there is a key aspect that relates circular codes to symmetries and transformations that remains to a large extent unexplored. In this article we aim at addressing the issue by studying the symmetries and transformations that connect different circular codes. The main result is that the class of 216 C3 maximal self-complementary codes can be partitioned into 27 equivalence classes defined by a particular set of transformations. We show that such transformations can be put in a group theoretic framework with an intuitive geometric interpretation. More general mathematical results about symmetry transformations which are valid for any kind of circular codes are also presented. Our results pave the way to the study of the biological consequences of the mathematical structure behind circular codes and contribute to shed light on the evolutionary steps that led to the observed symmetries of present codes. PMID:25008961

  2. dc-free coset codes

    NASA Technical Reports Server (NTRS)

    Deng, Robert H.; Herro, Mark A.

    1988-01-01

    A class of block coset codes with disparity and run-length constraints are studied. They are particularly well suited for high-speed optical fiber links and similar channels, where dc-free pulse formats, channel error control, and low-complexity encoder-decoder implementations are required. The codes are derived by partitioning linear block codes. The encoder and decoder structures are the same as those of linear block codes with only slight modifications. A special class of dc-free coset block codes are derived from BCH codes with specified bounds on minimum distance, disparity, and run length. The codes have low disparity levels (a small running digital sum) and good error-correcting capabilities.

  3. Permutation-invariant quantum codes

    NASA Astrophysics Data System (ADS)

    Ouyang, Yingkai

    2014-12-01

    A quantum code is a subspace of a Hilbert space of a physical system chosen to be correctable against a given class of errors, where information can be encoded. Ideally, the quantum code lies within the ground space of the physical system. When the physical model is the Heisenberg ferromagnet in the absence of an external magnetic field, the corresponding ground space contains all permutation-invariant states. We use techniques from combinatorics and operator theory to construct families of permutation-invariant quantum codes. These codes have length proportional to t2; one family of codes perfectly corrects arbitrary weight t errors, while the other family of codes approximately correct t spontaneous decay errors. The analysis of our codes' performance with respect to spontaneous decay errors utilizes elementary matrix analysis, where we revisit and extend the quantum error correction criterion of Knill and Laflamme, and Leung, Chuang, Nielsen and Yamamoto.

  4. Estimation of stream depletion using values of capacitance

    NASA Astrophysics Data System (ADS)

    Baldenkov, Mikhail; Filimonova, Elena

    2014-05-01

    Compensation pumping is used to alleviate deficiencies in streamflow discharge during dry seasons. Short-term groundwater pumping can use aquifer storage instead of catchment-zone water until the drawdown reaches the edge of the stream. Stream-aquifer interactions are the key component of the hydrologic budgets and estimation of stream depletion has top-priority when evaluating the effectiveness of application of seasonal compensation pumping. Numerous analytical equations have been developed to assess the influence of groundwater pumping on nearby streams (C.V. Theis, R.E. Glover, C.G. Balmer, M.S. Hantush, C.T. Jenkins, B. Hunt, J. Bredehoeft, V.A. Zlotnik, E.L. Minkin, N.N. Lapshin, F.M. Bochever and other researchers). R.B. Wallace and Y. Darama obtained solution for cyclic conditions groundwater pumping. Numerical model approaches used in difficult hydrogeological conditions. It is offered to estimate stream depletion by seasonal pumping using values of capacitance (complex, dimensionless parameter of an aquifer system that defines the delayed effect on steamflow when there is groundwater pumping). Capacitance (C) is determined by the following equation: ( ) L* C = f( °---) , TS-Δt where S and T are the aquifer specific yield (or storage coefficient for a confined aquifer) and transmissivity, respectively; Δt is the pumping time inside one cycle, L* is the summarizing distance between the compensation well and stream edge; in some cases it can involve a function of the stream leakance and vertical leakance of the impermeable layer. Three typical hydraulic cases of compensation pumping were classified depending on their capacitance structure (i.e. the relationship between surface water and groundwater): (a) perfect hydraulic connection between the stream and aquifer; (b) imperfect hydraulic connection between the stream and aquifer; and (c) essentially imperfect hydraulic connection between the stream and the underlying confined aquifer. The form of

  5. Making your code citable with the Astrophysics Source Code Library

    NASA Astrophysics Data System (ADS)

    Allen, Alice; DuPrie, Kimberly; Schmidt, Judy; Berriman, G. Bruce; Hanisch, Robert J.; Mink, Jessica D.; Nemiroff, Robert J.; Shamir, Lior; Shortridge, Keith; Taylor, Mark B.; Teuben, Peter J.; Wallin, John F.

    2016-01-01

    The Astrophysics Source Code Library (ASCL, ascl.net) is a free online registry of codes used in astronomy research. With nearly 1,200 codes, it is the largest indexed resource for astronomy codes in existence. Established in 1999, it offers software authors a path to citation of their research codes even without publication of a paper describing the software, and offers scientists a way to find codes used in refereed publications, thus improving the transparency of the research. It also provides a method to quantify the impact of source codes in a fashion similar to the science metrics of journal articles. Citations using ASCL IDs are accepted by major astronomy journals and if formatted properly are tracked by ADS and other indexing services. The number of citations to ASCL entries increased sharply from 110 citations in January 2014 to 456 citations in September 2015. The percentage of code entries in ASCL that were cited at least once rose from 7.5% in January 2014 to 17.4% in September 2015. The ASCL's mid-2014 infrastructure upgrade added an easy entry submission form, more flexible browsing, search capabilities, and an RSS feeder for updates. A Changes/Additions form added this past fall lets authors submit links for papers that use their codes for addition to the ASCL entry even if those papers don't formally cite the codes, thus increasing the transparency of that research and capturing the value of their software to the community.

  6. Practices in Code Discoverability: Astrophysics Source Code Library

    NASA Astrophysics Data System (ADS)

    Allen, A.; Teuben, P.; Nemiroff, R. J.; Shamir, L.

    2012-09-01

    Here we describe the Astrophysics Source Code Library (ASCL), which takes an active approach to sharing astrophysics source code. ASCL's editor seeks out both new and old peer-reviewed papers that describe methods or experiments that involve the development or use of source code, and adds entries for the found codes to the library. This approach ensures that source codes are added without requiring authors to actively submit them, resulting in a comprehensive listing that covers a significant number of the astrophysics source codes used in peer-reviewed studies. The ASCL now has over 340 codes in it and continues to grow. In 2011, the ASCL has on average added 19 codes per month. An advisory committee has been established to provide input and guide the development and expansion of the new site, and a marketing plan has been developed and is being executed. All ASCL source codes have been used to generate results published in or submitted to a refereed journal and are freely available either via a download site or from an identified source. This paper provides the history and description of the ASCL. It lists the requirements for including codes, examines the advantages of the ASCL, and outlines some of its future plans.

  7. Assessment of Volume Depletion in Children with Malaria

    PubMed Central

    2004-01-01

    ABSTRACT Background The degree of volume depletion in severe malaria is currently unknown, although knowledge of fluid compartment volumes can guide therapy. To assist management of severely ill children, and to test the hypothesis that volume changes in fluid compartments reflect disease severity, we measured body compartment volumes in Gabonese children with malaria. Methods and Findings Total body water volume (TBW) and extracellular water volume (ECW) were estimated in children with severe or moderate malaria and in convalescence by tracer dilution with heavy water and bromide, respectively. Intracellular water volume (ICW) was derived from these parameters. Bioelectrical impedance analysis estimates of TBW and ECW were calibrated against dilution methods, and bioelectrical impedance analysis measurements were taken daily until discharge. Sixteen children had severe and 19 moderate malaria. Severe childhood malaria was associated with depletion of TBW (mean [SD] of 37 [33] ml/kg, or 6.7% [6.0%]) relative to measurement at discharge. This is defined as mild dehydration in other conditions. ECW measurements were normal on admission in children with severe malaria and did not rise in the first few days of admission. Volumes in different compartments (TBW, ECW, and ICW) were not related to hyperlactataemia or other clinical and laboratory markers of disease severity. Moderate malaria was not associated with a depletion of TBW. Conclusions Significant hypovolaemia does not exacerbate complications of severe or moderate malaria. As rapid rehydration of children with malaria may have risks, we suggest that fluid replacement regimens should aim to correct fluid losses over 12–24 h. PMID:15526044

  8. Satellite-based estimates of groundwater depletion in India.

    PubMed

    Rodell, Matthew; Velicogna, Isabella; Famiglietti, James S

    2009-08-20

    Groundwater is a primary source of fresh water in many parts of the world. Some regions are becoming overly dependent on it, consuming groundwater faster than it is naturally replenished and causing water tables to decline unremittingly. Indirect evidence suggests that this is the case in northwest India, but there has been no regional assessment of the rate of groundwater depletion. Here we use terrestrial water storage-change observations from the NASA Gravity Recovery and Climate Experiment satellites and simulated soil-water variations from a data-integrating hydrological modelling system to show that groundwater is being depleted at a mean rate of 4.0 +/- 1.0 cm yr(-1) equivalent height of water (17.7 +/- 4.5 km(3) yr(-1)) over the Indian states of Rajasthan, Punjab and Haryana (including Delhi). During our study period of August 2002 to October 2008, groundwater depletion was equivalent to a net loss of 109 km(3) of water, which is double the capacity of India's largest surface-water reservoir. Annual rainfall was close to normal throughout the period and we demonstrate that the other terrestrial water storage components (soil moisture, surface waters, snow, glaciers and biomass) did not contribute significantly to the observed decline in total water levels. Although our observational record is brief, the available evidence suggests that unsustainable consumption of groundwater for irrigation and other anthropogenic uses is likely to be the cause. If measures are not taken soon to ensure sustainable groundwater usage, the consequences for the 114,000,000 residents of the region may include a reduction of agricultural output and shortages of potable water, leading to extensive socioeconomic stresses. PMID:19675570

  9. Complement depletion aggravates Staphylococcus aureus septicaemia and septic arthritis

    PubMed Central

    Sakiniene, E; Bremell, T; Tarkowski, A

    1999-01-01

    The aim of the study was to assess the role of the complement system in Staphylococcus aureus arthritis and septicaemia. The murine model of haematogenously acquired septic arthritis was used, injecting intravenously toxic shock syndrome toxin-1 (TSST-1), producing S. aureus LS-1. Complement was depleted using cobra venom factor (CVF). Evaluation of arthritis was performed clinically and histopathologically. In addition, the effect of complement depletion on the phagocytic activity of leucocytes was assessed in vivo and in vitro. Six days after inoculation of S. aureus the prevalence of arthritis in decomplemented mice was three-fold higher than that in controls (91% versus 25%). The clinical severity of arthritis at the end of the experiment, expressed as arthritic index, was 7.3 and 1.9, respectively. These findings were confirmed by histological index of synovitis as well as of cartilage and/or bone destruction being significantly higher in decomplemented mice than in controls (9.8 ± 1.7 versus 4.9 ± 1.2, P < 0.05; and 7.9 ± 1.7 versus 3.0 ± 0.9, P < 0.05, respectively). Also, the septicaemia-induced mortality was clearly higher in decomplemented mice compared with the controls. CVF treatment significantly reduced in vivo polymorphonuclear cell-dependent inflammation induced by subcutaneous injection of olive oil and mirroring the capacity of polymorphonuclear cells (PMNC) to migrate and/or extravasate. Besides, the decomplementation procedure significantly impaired phagocytic activity of peripheral blood leucocytes in vitro, since the number of phagocytes being able to ingest bacteria decreased by 50% when the cells were maintained in decomplemented serum compared with those in intact serum. The conclusion is that complement depletion aggravates the clinical course of S. aureus arthritis and septicaemia, possibly by a combination of decreased migration/extravasation of PMNC and an impairment of phagocytosis. PMID:9933426

  10. On the depletion of HCl in the Antarctic polar vortex

    NASA Astrophysics Data System (ADS)

    Wegner, Tobias; Kinnison, Douglas; Garcia, Rolando; Madronich, Sasha; Solomon, Susan; von Hobe, Marc

    2013-04-01

    Satellite observations and numerical modeling are used to constrain the mechanisms that deplete gas-phase HCl in the Antarctic vortex. Our analysis shows that current formulations of heterogeneous chlorine activation cannot explain the observed loss of gas-phase HCl in SD-WACCM. Uncertainties in photochemistry, transport and initial conditions are investigated, and it is shown that ClONO2 formed after photolysis of condensed-phase nitrate increases the loss of HCl through heterogeneous chemistry, especially in the sunlit edge of the vortex. This process eventually produces sufficient NOx to completely deplete gas-phase HCl but this occurs too late compared to observations. Our results suggest that the more likely primary mechanism for decreases in gas-phase HCl from the beginning of the polar night until about the middle of July is active partitioning between the gas and condensed phase. Since the HCl taken up into particles is quickly released upon warming, it does not represent irreversible loss of chlorine, only temporary removal from the gas-phase. With HCl dissolved in STS particles, the associated decrease in gas-phase HCl is not an indicator of chlorine activation. The solubility of HCl in STS is highly sensitive to water vapor and temperature, such that accurate simulation of both is necessary to reproduce the observed depletion of gas-phase HCl. With the reference setup of SD-WACCM hardly any HCl is simulated to be sequestered in STS. A negative offset has to be applied to model temperatures to achieve significant partitioning of HCl into the condensed phase. While our results imply substantial changes in chlorine partitioning during the polar night, the ozone loss is insensitive to them.

  11. PKCι depletion initiates mitotic slippage-induced senescence in glioblastoma.

    PubMed

    Restall, Ian J; Parolin, Doris A E; Daneshmand, Manijeh; Hanson, Jennifer E L; Simard, Manon A; Fitzpatrick, Megan E; Kumar, Ritesh; Lavictoire, Sylvie J; Lorimer, Ian A J

    2015-01-01

    Cellular senescence is a tumor suppressor mechanism where cells enter a permanent growth arrest following cellular stress. Oncogene-induced senescence (OIS) is induced in non-malignant cells following the expression of an oncogene or inactivation of a tumor suppressor. Previously, we have shown that protein kinase C iota (PKCι) depletion induces cellular senescence in glioblastoma cells in the absence of a detectable DNA damage response. Here we demonstrate that senescent glioblastoma cells exhibit an aberrant centrosome morphology. This was observed in basal levels of senescence, in p21-induced senescence, and in PKCι depletion-induced senescence. In addition, senescent glioblastoma cells are polyploid, Ki-67 negative and arrest at the G1/S checkpoint, as determined by expression of cell cycle regulatory proteins. These markers are all consistent with cells that have undergone mitotic slippage. Failure of the spindle assembly checkpoint to function properly can lead to mitotic slippage, resulting in the premature exit of mitotic cells into the G1 phase of the cell cycle. Although in G1, these cells have the replicated DNA and centrosomal phenotype of a cell that has entered mitosis and failed to divide. Overall, we demonstrate that PKCι depletion initiates mitotic slippage-induced senescence in glioblastoma cells. To our knowledge, this is the first evidence of markers of mitotic slippage directly in senescent cells by co-staining for senescence-associated β-galactosidase and immunofluorescence markers in the same cell population. We suggest that markers of mitotic slippage be assessed in future studies of senescence to determine the extent of mitotic slippage in the induction of cellular senescence. PMID:26208522

  12. The relationship between skin cancers, solar radiation and ozone depletion.

    PubMed Central

    Moan, J.; Dahlback, A.

    1992-01-01

    During the period 1957-1984 the annual age-adjusted incidence rate of cutaneous malignant melanoma (CMM) increased by 350% for men and 440% for women in Norway. The annual exposure to carcinogenic sunlight in Norway, calculated by use of measured ozone levels, showed no increasing trend during the same period. Thus, ozone depletion is not a cause of the increasing trend of the incidence rates of skin cancers. The incidence rates of basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) increase with decreasing latitude in Norway. The same is true for CMM in Norway, Sweden, and Finland. Our data were used to estimate the implications of a future ozone depletion for the incidence rates of skin cancer: a 10% ozone depletion was found to give rise to a 16-18% increase in the incidence rate of SCC (men and women), a 19% increase in the incidence rate of CMM for men and a 32% increase in the incidence rate of CMM for women. The difference between the numbers for men and women is almost significant and may be related to a different intermittent exposure pattern to sunlight of the two sexes. The increasing trend in the incidence rates of CMM is strongest for the trunk and lower extremities of women, followed by that for the trunk of men. The increasing incidence rates of skin cancers as well as the changing pattern of incidence on different parts of the body is most likely due to changing habits of sun exposure. Comparisons of relative densities of CMM, SCC, LMM and SCC falling per unit area of skin at different parts of the body indicate that sun exposure is the main cause of these cancer forms although other unknown factors may play significant roles as well. For the population as a whole sun exposure during vacations to sunny countries has so far been of minor importance in skin cancer induction. PMID:1616864

  13. Inhibition of lytic infection of pseudorabies virus by arginine depletion

    SciTech Connect

    Wang, H.-C.; Kao, Y.-C.; Chang, T-J.; Wong, M.-L. . E-mail: mlwong@dragon.nchu.edu.tw

    2005-08-26

    Pseudorabies virus (PRV) is a member of Alphahepesviruses; it is an enveloped virus with a double-stranded DNA genome. Polyamines (such as spermine and spermidine) are ubiquitous in animal cells and participate in cellular proliferation and differentiation. Previous results of our laboratory showed that the PRV can accomplish lytic infection either in the presence of exogenous spermine (or spermidine) or depletion of cellular polyamines. The amino acid arginine is a precursor of polyamine biosynthesis. In this work, we investigated the role of arginine in PRV infection. It was found that the plaque formation of PRV was inhibited by arginase (enzyme catalyzing the conversion of arginine into ornithine and urea) treatment whereas this inhibition can be reversed by exogenous arginine, suggesting that arginine is essential for PRV proliferation. Western blotting was conducted to study the effect of arginine depletion on the levels of structural proteins of PRV in virus-infected cells. Four PRV structural proteins (gB, gE, UL47, and UL48) were chosen for examination, and results revealed that the levels of viral proteins were obviously reduced in long time arginase treatment. However, the overall protein synthesis machinery was apparently not influenced by arginase treatment either in mock or PRV-infected cells. Analyzing with native gel, we found that arginase treatment affected the mobility of PRV structural proteins, suggesting the conformational change of viral proteins by arginine depletion. Heat shock proteins, acting as molecular chaperons, participate in protein folding and translocation. Our results demonstrated that long time arginase treatment could reduce the expression of cellular heat shock proteins 70 (hsc70 and hsp70), and transcriptional suppression of heat shock protein 70 gene promoter was one of the mechanisms involved in this reduced expression.

  14. Lattice physics capabilities of the SCALE code system using TRITON

    SciTech Connect

    DeHart, M. D.

    2006-07-01

    This paper describes ongoing calculations used to validate the TRITON depletion module in SCALE for light water reactor (LWR) fuel lattices. TRITON has been developed to provide improved resolution for lattice physics mixed-oxide fuel assemblies as programs to burn such fuel in the United States begin to come online. Results are provided for coupled TRITON/PARCS analyses of an LWR core in which TRITON was employed for generation of appropriately weighted few-group nodal cross-sectional sets for use in core-level calculations using PARCS. Additional results are provided for code-to-code comparisons for TRITON and a suite of other depletion packages in the modeling of a conceptual next-generation boiling water reactor fuel assembly design. Results indicate that the set of SCALE functional modules used within TRITON provide an accurate means for lattice physics calculations. Because the transport solution within TRITON provides a generalized-geometry capability, this capability is extensible to a wide variety of non-traditional and advanced fuel assembly designs. (authors)

  15. Microstructure of depleted uranium under uniaxial strain conditions

    SciTech Connect

    Zurek, A.K.; Embury, J.D.; Kelly, A.; Thissell, W.R.; Gustavsen, R.L.; Vorthman, J.E.; Hixson, R.H.

    1997-09-01

    Uranium samples of two different purities were used for spall strength measurements. Samples of depleted uranium were taken from very high purity material (38 ppM carbon) and from material containing 280 ppM C. Experimental conditions were chosen to effectively arrest the microstructural damage at two places in the development to full spall separation. Samples were soft recovered and characterized with respect to the microstructure and the form of damage. This allowed determination of the dependence of spall mechanisms on stress level, stress state, and sample purity. This information is used in developing a model to predict the mode of fracture.

  16. Implementation, verification, and application of multicycle depletion perturbation theory

    SciTech Connect

    White, J.R.; Burns, T.J.; Williams, M.L.

    1980-01-01

    Several application-oriented features of generalized depletion perturbation theory (DPT) are analyzed from the viewpoint of the reactor designer. The detailed theory is first reduced to some new terminology necessary for an adequate understanding of DPT. Using this terminology, the main features and computational accuracy of this new technique are illustrated through representative DPT calculations utilizing a CDS-type heterogeneous reactor model. Several examples are presented that indicate the potential of DPT methods as an alternate computational tool for certain types of reactor physics analyses.

  17. Depletion effect of oxide semiconductor analyzed by Hall effects.

    PubMed

    Oh, Teresa

    2014-12-01

    This letter discusses the tunneling behavior of amorphous indium-gallium-zinc-oxide (a-IGZO) analyzed through the observation of its Hall effects. The properties of the a-IGZO changed from those of a majority carrier to those of a minority carrier after the annealing process as a result of the electron-hole recombination due to the thermal activation energy and the formation of a depletion layer with a high-potential Schottky barrier. Therefore, the diffusion current of these minority charge carriers caused ambipolar transfer characteristics, a tunneling behavior, in the metal-oxide semiconductor (MOS) transistor. PMID:25971008

  18. Fuel-Cycle of 'CANDLE' Burnup with Depleted Uranium

    SciTech Connect

    Hiroshi, Sekimoto

    2006-07-01

    A new reactor burnup strategy CANDLE (Constant Axial shape of Neutron flux, nuclide densities and power shape During Life of Energy producing reactor) was proposed, where shapes of neutron flux, nuclide densities and power density distributions remain constant but move upward (or downward) along its core axis. This burnup strategy can derive many merits, especially from safety point of view. The change of excess reactivity along burnup is theoretically zero, and the core characteristics, such as power feedback coefficients and power peaking factor, are not changed along burnup. Application of this burnup strategy to neutron rich fast reactors makes excellent performances. Only natural or depleted uranium is required for the replacing fuels. About 40 % of natural or depleted uranium undergoes fission without the conventional reprocessing and enrichment. If the LWR produced energy of X Joules, the CANDLE reactor can produce about 50 X Joules from the depleted uranium left at the enrichment facility for the LWR fuel. If we can say LWRs have produced energy sufficient for full 20 years, we can produce the energy for 1000 years by using the CANDLE reactors with depleted uranium. We need not mine any uranium ore, and do not need reprocessing facility. The burnup of spent fuel becomes 10 times. Therefore, the spent fuel amount per produced energy is also reduced to one-tenth. The equilibrium core contains a lot of instable materials such as higher actinides and fission products, the enough amounts of which can not be obtained easily. The construction of the initial core is a difficult problem. However, by using enriched uranium substituted for actinides in the equilibrium core, we can construct the initial core whose power profile is similar to the equilibrium one and will reach the equilibrium state without any big change during transient. At present we do not have any material standing for such a high burnup. However, the CANDLE burnup can be realized by employing

  19. Consistent cosmic microwave background spectra from quantum depletion

    NASA Astrophysics Data System (ADS)

    Casadio, Roberto; Kühnel, Florian; Orlandi, Alessio

    2015-09-01

    Following a new quantum cosmological model proposed by Dvali and Gomez, we quantitatively investigate possible modifications to the Hubble parameter and following corrections to the cosmic microwave background spectrum. In this model, scalar and tensor perturbations are generated by the quantum depletion of the background inflaton and graviton condensate respectively. We show how the inflaton mass affects the power spectra and the tensor-to-scalar ratio. Masses approaching the Planck scale would lead to strong deviations, while standard spectra are recovered for an inflaton mass much smaller than the Planck mass.

  20. Dystroglycan depletion inhibits the functions of differentiated HL-60 cells.

    PubMed

    Martínez-Zárate, Alma Delia; Martínez-Vieyra, Ivette; Alonso-Rangel, Lea; Cisneros, Bulmaro; Winder, Steve J; Cerecedo, Doris

    2014-06-01

    Dystroglycan has recently been characterized in blood tissue cells, as part of the dystrophin glycoprotein complex but to date nothing is known of its role in the differentiation process of neutrophils. We have investigated the role of dystroglycan in the human promyelocytic leukemic cell line HL-60 differentiated to neutrophils. Depletion of dystroglycan by RNAi resulted in altered morphology and reduced properties of differentiated HL-60 cells, including chemotaxis, respiratory burst, phagocytic activities and expression of markers of differentiation. These findings strongly implicate dystroglycan as a key membrane adhesion protein involved in the differentiation process in HL-60 cells. PMID:24792180