Science.gov

Sample records for groups cross section

  1. Extension of the Bgl Broad Group Cross Section Library

    NASA Astrophysics Data System (ADS)

    Kirilova, Desislava; Belousov, Sergey; Ilieva, Krassimira

    2009-08-01

    The broad group cross-section libraries BUGLE and BGL are applied for reactor shielding calculation using the DOORS package based on discrete ordinates method and multigroup approximation of the neutron cross-sections. BUGLE and BGL libraries are problem oriented for PWR or VVER type of reactors respectively. They had been generated by collapsing the problem independent fine group library VITAMIN-B6 applying PWR and VVER one-dimensional radial model of the reactor middle plane using the SCALE software package. The surveillance assemblies (SA) of VVER-1000/320 are located on the baffle above the reactor core upper edge in a region where geometry and materials differ from those of the middle plane and the neutron field gradient is very high which would result in a different neutron spectrum. That is why the application of the fore-mentioned libraries for the neutron fluence calculation in the region of SA could lead to an additional inaccuracy. This was the main reason to study the necessity for an extension of the BGL library with cross-sections appropriate for the SA region. Comparative analysis of the neutron spectra of the SA region calculated by the VITAMIN-B6 and BGL libraries using the two-dimensional code DORT have been done with purpose to evaluate the BGL applicability for SA calculation.

  2. A Multigroup Reaction Cross-Section Collapsing Code and Library of 154-Group Fission-Product Cross Sections.

    Energy Science and Technology Software Center (ESTSC)

    1983-03-23

    Version 01/02 The code reads multigroup cross sections from a compatible data file and collapses user-selected reaction cross sections to any few-group structure using one of a variety of user neutron flux spectrum options given below: Option Flux description 1 Built-in function including Maxwellian, fission, fusion and slowing-down regions and requiring user-specified parameters and energy-region boundaries. 2 Set of log-log flux-energy interpolation points read from input cross-section data file. 3 Set of log-log flux-energy interpolationmore » points read from user-supplied card input. 4 - 6 Histogram flux values read from user-supplied card input in arbitrary group structure in units of flux-per unit-energy, flux-per-unit lethargy, or integral group flux. LAFPX-E may be used to collapse any set of multigroup reaction cross sections furnished in the required format. However, the code was developed for, and is furnished with, a library of 154-group fission-product cross sections processed from ENDF/B-IV with a typical light water reactor (LWR) flux spectrum and temperature. Four-group radiative capture cross sections produced for LWR calculations are tabulated in the code documentation and are incorporated in the EPRI-CINDER data library, RSIC Code Package CCC-309.« less

  3. 70 Group Neutron Fast Reactor Cross Section Set and 25 Group Neutron Fast Reactor Cross Section Set.

    Energy Science and Technology Software Center (ESTSC)

    1984-10-29

    Version 00 These multigroup cross sections are used in fast reactor calculations. The benchmark calculations for the 23 fast critical assemblies used in the benchmark tests of JFS-2 were performed with one-dimensional diffusion theory by using the JFS-3-J2 set.

  4. Nonnegative Anisotropic Group Cross Sections: A Hybrid Monte Carlo-Discrete Elements-Discrete Ordinates Approach

    SciTech Connect

    DelGrande, J. Mark; Mathews, Kirk A.

    2001-09-15

    Conventional discrete ordinates transport calculations often produce negative fluxes due to unphysical negative scattering cross sections and/or as artifacts of spatial differencing schemes such as diamond difference. Inherently nonnegative spatial methods, such as the nonlinear, exponential characteristic spatial quadrature, eliminate negative fluxes while providing excellent accuracy, presuming the group-to-group, ordinate-to-ordinate cross sections are all nonnegative. A hybrid approach is introduced in which the flow from spatial cell to spatial cell uses discrete ordinates spatial quadratures, while anisotropic scattering of flux from one energy-angle bin (energy group and discrete element of solid angle) to another such bin is modeled using a Monte Carlo simulation to evaluate the bin-to-bin cross sections. The directional elements tile the sphere of directions; the ordinates for the spatial quadrature are at the centroids of the elements. The method is developed and contrasted with previous schemes for positive cross sections. An algorithm for evaluating the Monte Carlo (MC)-discrete elements (MC-DE) cross sections is described, and some test cases are presented. Transport calculations using MC-DE cross sections are compared with calculations using conventional cross sections and with MCNP calculations. In this testing, the new method is about as accurate as the conventional approach, and often is more accurate. The exponential characteristic spatial quadrature, using the MC-DE cross sections, is shown to provide useful results where linear characteristic and spherical harmonics provide negative scalar fluxes in every cell in a region.

  5. A program for the conversion of fine group flux density and cross section data to coarse group values

    NASA Astrophysics Data System (ADS)

    Rieffe, H. C.

    1981-04-01

    The computer program FITOCO is described which converts neutron spectrum data and group cross section data from a fine group structure into a coarser group structure. This type of conversion has to be used often in neutron activation spectrometry when unfolding procedures are applied. The program requires as input a representation of the weighing spectrum and a neutron cross section library, both in the fine group structure of the SAND-II type. The output group structure is determined by the input cards of the program. The program can calculate also the effective coarse group cross section values for a cross section of a material inside a detector cover (i.e., B-10 or Cd).

  6. Code System to Create Broad-Group Cross Sections with Resonance Interference and Self-Shielding from Fine-Group and Pointwise Cross Sections.

    Energy Science and Technology Software Center (ESTSC)

    2007-10-31

    Version: 02 RSICC received MICROX‑2 through the NEADB (identifier is NEA‑1562/02.) This is an improved version of the original MICROX-2 two-region spectrum code, which was developed at General Atomic, to prepare broad group neutron cross sections for use in diffusion-and/or transport theory codes from an input library of fine group and pointwise cross sections. The MICROX-2 code can explicitly account for the overlap and interference effects between resonances in both the resonance and thermal neutronmore » energy ranges and allows the simulta?neous treatment of leakage and resonance self-shielding in doubly heterogeneous lattice cells. MICROR runs as a module of NJOY 89.62; the NJOY calling module is included in the package. This release has been changed in that the MODER module from NJOY 94.0, too, has been included as subprogramm of NJOY 89.62, so as to make the code system completely selfconsistent, i.e. without requiring the use of some NJOY version to convert pendf and gendf from coded to binary. Using data from pointwise and groupwise NJOY tapes, the stand-alone MICROR reformatting program produces files containing basic nuclear data to be used by MICROX-2. MICROR edits PENDF and GENDF data files from NJOY to create FDTAP?E, GGTA?PE and GARTA?PE input files for MICROX-2. NJOY is not included in this package. Some data libraries are included for example cases; these data were generated from data in 193 groups as well as from point-wise cross sections from NJOY (Edition 89.62).« less

  7. Language Factors Associated with Achievement Grouping in Math Classrooms: A Cross-Sectional and Longitudinal Study

    ERIC Educational Resources Information Center

    Chang, Mido; Singh, Kusum; Filer, Kimberly

    2009-01-01

    The study examines the effects of classroom achievement grouping (AG) practices on the early mathematics performance of language-minority students and compares their mathematics achievement to that of English-speaking majority students. Using a nationally representative database of the USA, both cross-sectional and longitudinal analyses were done.…

  8. Analysis of human hair cross sections from two different population groups by Nuclear Microscopy

    NASA Astrophysics Data System (ADS)

    Pineda-Vargas, C. A.; Eisa, M. E. M.

    2010-06-01

    Trace element analysis of hair is used as a screening technique to assess body-nutrient levels and/or toxicity due to environmental pollutants. With the aim to compare element content and spatial distribution within scalp hair-shaft cross sections of two distinct human population groups, and to assess possible similarities and/or differences, hair samples from Sudan and South Africa were collected. Proton backscattering and Micro-PIXE were used to determine the matrix composition and content of light and middle transition elements, with beam energies of 1.5 and 3.0 MeV. Mapping analysis showed a relatively similar content distribution for S, Cl, K and Ca within each group. However significant differences, particularly for heavier metals, such as Fe and Zn were also found. Correspondence Analysis of the data showed a clear separation between the two groups when the total content over the hair cross section was considered.

  9. Sensitivity Analysis of Nuclide Importance to One-Group Neutron Cross Sections

    SciTech Connect

    Sekimoto, Hiroshi; Nemoto, Atsushi; Yoshimura, Yoshikane

    2001-07-15

    The importance of nuclides is useful when investigating nuclide characteristics in a given neutron spectrum. However, it is derived using one-group microscopic cross sections, which may contain large errors or uncertainties. The sensitivity coefficient shows the effect of these errors or uncertainties on the importance.The equations for calculating sensitivity coefficients of importance to one-group nuclear constants are derived using the perturbation method. Numerical values are also evaluated for some important cases for fast and thermal reactor systems.Many characteristics of the sensitivity coefficients are derived from the derived equations and numerical results. The matrix of sensitivity coefficients seems diagonally dominant. However, it is not always satisfied in a detailed structure. The detailed structure of the matrix and the characteristics of coefficients are given.By using the obtained sensitivity coefficients, some demonstration calculations have been performed. The effects of error and uncertainty of nuclear data and of the change of one-group cross-section input caused by fuel design changes through the neutron spectrum are investigated. These calculations show that the sensitivity coefficient is useful when evaluating error or uncertainty of nuclide importance caused by the cross-section data error or uncertainty and when checking effectiveness of fuel cell or core design change for improving neutron economy.

  10. Revised methods for few-group cross sections generation in the Serpent Monte Carlo code

    SciTech Connect

    Fridman, E.; Leppaenen, J.

    2012-07-01

    This paper presents new calculation methods, recently implemented in the Serpent Monte Carlo code, and related to the production of homogenized few-group constants for deterministic 3D core analysis. The new methods fall under three topics: 1) Improved treatment of neutron-multiplying scattering reactions, 2) Group constant generation in reflectors and other non-fissile regions and 3) Homogenization in leakage-corrected criticality spectrum. The methodology is demonstrated by a numerical example, comparing a deterministic nodal diffusion calculation using Serpent-generated cross sections to a reference full-core Monte Carlo simulation. It is concluded that the new methodology improves the results of the deterministic calculation, and paves the way for Monte Carlo based group constant generation. (authors)

  11. 30-Group Neutron, 12-Group Photon Cross Sections from ENDF/B-V in MATSX Format.

    Energy Science and Technology Software Center (ESTSC)

    1985-12-30

    Version: 00 The library was prepared with a fusion + fission + l/E + thermal Maxwellian weight function and has proved useful for many high energy calculations, including criticals such as GODIVA. It works reasonably well for many shielding problems where resonance selfshielding is not too important. The energy group structures for MATXSSA are listed in Table 1, the materials with neutron scattering data in Table 2, those with photon production data in Table 3,more » and those with photon scattering data In Table 4.« less

  12. 30-Group Neutron, 12-Group Photon Cross Sections from ENDF/B-IV in MATXS Format.

    Energy Science and Technology Software Center (ESTSC)

    1985-12-30

    Version: 00 The library was prepared with a fusion + fission + l/E + thermal Maxwellian weight function and has proved useful for many high energy calculations, including criticals such as GODIVA. It works reasonably well for many shielding problems where resonance selfshielding is not too important. The energy group structures for MATXSl are listed in Table 1, the materials with neutron scattering data in Table 2, those with photon production data in Table 3,more » and those with photon scattering data in Table 4.« less

  13. Nuclear Data Uncertainty Propagation in Depletion Calculations Using Cross Section Uncertainties in One-group or Multi-group

    SciTech Connect

    Díez, C.J.; Cabellos, O.; Martínez, J.S.

    2015-01-15

    Several approaches have been developed in last decades to tackle nuclear data uncertainty propagation problems of burn-up calculations. One approach proposed was the Hybrid Method, where uncertainties in nuclear data are propagated only on the depletion part of a burn-up problem. Because only depletion is addressed, only one-group cross sections are necessary, and hence, their collapsed one-group uncertainties. This approach has been applied successfully in several advanced reactor systems like EFIT (ADS-like reactor) or ESFR (Sodium fast reactor) to assess uncertainties on the isotopic composition. However, a comparison with using multi-group energy structures was not carried out, and has to be performed in order to analyse the limitations of using one-group uncertainties.

  14. Nuclear Data Uncertainty Propagation in Depletion Calculations Using Cross Section Uncertainties in One-group or Multi-group

    NASA Astrophysics Data System (ADS)

    Díez, C. J.; Cabellos, O.; Martínez, J. S.

    2015-01-01

    Several approaches have been developed in last decades to tackle nuclear data uncertainty propagation problems of burn-up calculations. One approach proposed was the Hybrid Method, where uncertainties in nuclear data are propagated only on the depletion part of a burn-up problem. Because only depletion is addressed, only one-group cross sections are necessary, and hence, their collapsed one-group uncertainties. This approach has been applied successfully in several advanced reactor systems like EFIT (ADS-like reactor) or ESFR (Sodium fast reactor) to assess uncertainties on the isotopic composition. However, a comparison with using multi-group energy structures was not carried out, and has to be performed in order to analyse the limitations of using one-group uncertainties.

  15. Code System to Calculate Group-Averaged Cross Sections Using the Collision Probability Method.

    Energy Science and Technology Software Center (ESTSC)

    1995-05-17

    Version 00 This program calculates group-averaged cross sections for specific zones in a one-dimensional geometry. ROLAIDS-CPM is an extension of ROLAIDS from the PSR-315/AMPX-77 package. The main extension is the capability to use the collision probability method for a slab- or cylinder-geometry rather than the interface-currents method. This new version allows slowing down of neutrons in the energy range where the scattering is elastic and upscattering does not occur. The scattering sources are assumed tomore » be flat and isotropic in the different zones. The extra assumption of cosine currents at the interfaces of the zones (interface currents method) is not necessary for the collision probability method.« less

  16. Code System to Calculate Group-Averaged Cross Sections Using the Collision Probability Method.

    SciTech Connect

    KRUIJF, W. D.

    1995-05-17

    Version 00 This program calculates group-averaged cross sections for specific zones in a one-dimensional geometry. ROLAIDS-CPM is an extension of ROLAIDS from the PSR-315/AMPX-77 package. The main extension is the capability to use the collision probability method for a slab- or cylinder-geometry rather than the interface-currents method. This new version allows slowing down of neutrons in the energy range where the scattering is elastic and upscattering does not occur. The scattering sources are assumed to be flat and isotropic in the different zones. The extra assumption of cosine currents at the interfaces of the zones (interface currents method) is not necessary for the collision probability method.

  17. Many-Group Cross-Section Adjustment Techniques for Boiling Water Reactor Adaptive Simulation

    SciTech Connect

    Jessee, Matthew Anderson

    2011-01-01

    Computational capability has been developed to adjust multigroup neutron cross sections, including self-shielding correction factors, to improve the fidelity of boiling water reactor (BWR) core modeling and simulation. The method involves propagating multigroup neutron cross-section uncertainties through various BWR computational models to evaluate uncertainties in key core attributes such as core k{sub eff}, nodal power distributions, thermal margins, and in-core detector readings. Uncertainty-based inverse theory methods are then employed to adjust multigroup cross sections to minimize the disagreement between BWR core modeling predictions and observed (i.e., measured) plant data. For this paper, observed plant data are virtually simulated in the form of perturbed three-dimensional nodal power distributions with the perturbations sized to represent actual discrepancies between predictions and real plant data. The major focus of this work is to efficiently propagate multigroup neutron cross-section uncertainty through BWR lattice physics and core simulator calculations. The data adjustment equations are developed using a subspace approach that exploits the ill-conditioning of the multigroup cross-section covariance matrix to minimize computation and storage burden. Tikhonov regularization is also employed to improve the conditioning of the data adjustment equations. Expressions are also provided for posterior covariance matrices of both the multigroup cross-section and core attributes uncertainties.

  18. Measurement committee of the US cross section evaluation working group. Annual report, 1995

    SciTech Connect

    Smith, D.L.; McLane, V.

    1995-08-01

    The Cross Section Evaluation Working Group is a long-standing committee charged with the responsibility for organizing and overseeing the U.S. cross-section evaluation effort. It`s main product is the official U.S. evaluated nuclear data file, ENDF; the current version of this file is Version VI. All evaluations included in ENDF are reviewed and approved by CSEWG and issued by the U.S. Nuclear Data Center, Brookhaven National Laboratory. CSEWG is comprised of volunteers from the U.S. nuclear data community who possess expertise in evaluation methodologies and who collectively have been responsible for producing most of the evaluations included in ENDF. In 1992 CSEWG added the Measurements Committee to its list of standing committees and subcommittees. This was based on recognition of the importance of experimental data in the evaluation process as well as the realization that measurement activities in the U.S. were declining at an alarming rate. The mission of the Committee is to establish a network of experimentalists in the U.S. which would provide encouragement to the national nuclear data measurement effort through improved communication and facilitation of collaborative activities. The Committee currently has 19 members, and interested scientists are welcome to join the network simply by contacting the Chairman. For reference, the names of the current members and contact information are contained in this report. This annual report is the first such document issued by the Committee. It contains voluntary contributions from 10 laboratories in the U.S. which have been prepared by members of the Committee and submitted to the Chairman for compilation and editing. This report is being distributed in hard copy and is also available on-line via the National Nuclear Data Center, Brookhaven National Laboratory. It is hoped that the information provided here on the work that is going on at the reporting laboratories will prove interesting and stimulating to the readers.

  19. Validation of Nuclear Criticality Safety Software and 27 energy group ENDF/B-IV cross sections

    SciTech Connect

    Lee, B.L. Jr.

    1994-08-01

    The validation documented in this report is based on calculations that were executed during June through August 1992, and was completed in June 1993. The statistical analyses in Appendix C and Appendix D were completed in October 1993. This validation gives Portsmouth NCS personnel a basis for performing computerized KENO V.a calculations using the Martin Marietta Nuclear Criticality Safety Software. The first portion of the document outlines basic information in regard to validation of NCSS using ENDF/B-IV 27-group cross sections on the IBM 3090 at ORNL. A basic discussion of the NCSS system is provided, some discussion on the validation database and validation in general. Then follows a detailed description of the statistical analysis which was applied. The results of this validation indicate that the NCSS software may be used with confidence for criticality calculations at the Portsmouth Gaseous Diffusion Plant. When the validation results are treated as a single group, there is 95% confidence that 99.9% of future calculations of similar critical systems will have a calculated K{sub eff} > 0.9616. Based on this result the Portsmouth Nuclear Criticality Safety Department has adopted the calculational acceptance criteria that a k{sub eff} + 2{sigma} {le} 0.95 is safety subcritical. The validation of NCSS on the IBM 3090 at ORNL was extended to include NCSS on the IBM 3090 at K-25.

  20. 70 Group Neutron Fast Reactor Cross Section Set Based on JENDL-2B.

    Energy Science and Technology Software Center (ESTSC)

    1984-02-06

    Version 00 These multigroup cross sections are used in fast reactor calculations. The benchmark calculations for the 23 fast critical assemblies used in the benchmark tests of JFS-2 were performed with one-dimensional diffusion theory by using the JFS-3-J2 set.

  1. BOXER: Fine-flux Cross Section Condensation, 2D Few Group Diffusion and Transport Burnup Calculations

    Energy Science and Technology Software Center (ESTSC)

    2010-02-01

    Neutron transport, calculation of multiplication factor and neutron fluxes in 2-D configurations: cell calculations, 2-D diffusion and transport, and burnup. Preparation of a cross section library for the code BOXER from a basic library in ENDF/B format (ETOBOX).

  2. Association of Group B Streptococcus Colonization and Bovine Exposure: A Prospective Cross-Sectional Cohort Study

    PubMed Central

    Manning, Shannon D.; Springman, A. Cody; Million, Amber D.; Milton, Nicole R.; McNamara, Sara E.; Somsel, Patricia A.; Bartlett, Paul; Davies, H. Dele

    2010-01-01

    Background While Group B Streptococcus (GBS) human colonization and infection has long been suspected as originating from cows, several investigators have suggested that ongoing interspecies GBS transmission is unlikely due to genotyping data demonstrating that human and bovine-derived GBS strains represent mostly distinct populations. The possibility of ongoing transmission between humans and their livestock has not been systematically examined. Methodology/Principal Findings To examine ongoing interspecies transmission, we conducted a prospective cross-sectional cohort study of 68 families and their livestock. Stool specimens were collected from 154 people and 115 livestock; GBS was detected in 19 (12.3%) humans and 2 (1.7%) animals (bovine and sheep). Application of multilocus sequence typing (MLST) identified 8 sequence types (STs or clones), with STs 1 and 23 predominating. There were 11 families in which two members submitted stools and at least one had GBS colonization. In 3 of these families, both members (consisting of couples) were colonized, yielding a co-colonization rate of 27% (95% CI: 7%–61%). Two of these couples had strains with identical MLST, capsule (cps) genotype, susceptibility, and RAPD profiles. One couple co-colonized with ST-1 (cps5) strains also had a bovine colonized with the identical strain type. On multivariate analysis of questionnaire data, cattle exposure was a predictor of GBS colonization, with each unit increase in days of cattle exposure increasing the odds of colonization by 20% (P = 0.02). These results support interspecies transmission with additional evidence for transmission provided by the epidemiological association with cattle exposure. Conclusions/Significance Although GBS uncommonly colonizes livestock stools, increased frequency of cattle exposure was significantly associated with human colonization and one couple shared the same GBS strains as their bovine suggesting intraspecies transmission. These results

  3. Comparison of Serpent and HELIOS-2 as applied for the PWR few-group cross section generation

    SciTech Connect

    Fridman, E.; Leppaenen, J.; Wemple, C.

    2013-07-01

    This paper discusses recent modifications to the Serpent Monte Carlo code methodology and related to the calculation of few-group diffusion coefficients and reflector discontinuity factors The new methods were assessed in the following manner. First, few-group homogenized cross sections calculated by Serpent for a reference PWR core were compared with those generated 1 commercial deterministic lattice transport code HELIOS-2. Second, Serpent and HELIOS-2 fe group cross section sets were later employed by nodal diffusion code DYN3D for the modeling the reference PWR core. Finally, the nodal diffusion results obtained using the both cross section sets were compared with the full core Serpent Monte Carlo solution. The test calculations show that Serpent can calculate the parameters required for nodal analyses similar to conventional deterministic lattice codes. (authors)

  4. Fine-Group Cross Section Library Based on JEFF3.1 for Nuclear Fission Applications.

    Energy Science and Technology Software Center (ESTSC)

    2009-10-16

    Version 00 The NJOY-99.160 data processing system was used for the MATJEFF31.BOLIB library generation to assure the consistency with the previous generation of the VITJEFF31.BOLIB /6/ twin library, based on the same GENDF cross section data file. In particular it used a revised version of the GROUPR /7/ module, originally developed in ENEA-Bologna before the free release of an analogous GROUPR revised version with NJOY-99.161, in order to correctly deal with the non-Cartesian interpolation schemes,more » contained in 69 JEFF-3.1 evaluated nuclear data files. The TRANSX-2.15 /8/ code was then used to obtain the total (prompt + delayed) fission spectra for U-235, U-238 and Pu-239. These data, contained in the MATJEFF31.BOLIB package, are available in tabulated form as in the VITJEFF31.BOLIB library package. On the contrary the VITAMIN-B6, VITJEF22.BOLIB /9/ and MATJEF22.BOLIB /10/ similar library packages contain in tabulated form only the prompt components. MATJEFF31.BOLIB is a pseudo-problem-independent library based on the Bondarenko /11/ (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. The library contains 176 nuclides at 4 temperatures, obtained for the most part with 6 to 8 values for the background cross section. Thermal scattering cross sections were processed at all temperatures available in the JEFF-3.1 thermal scattering law data file for 6 additional bound nuclides (H-1 in light water (H-H2O), H-1 in polyethylene (H-CH2), H-1 in zirconium hydride (H-ZrH) (not contained in VITAMIN-B6, VITJEF22.BOLIB and MATJEF22.BOLIB), H-2 in heavy water (H2-D2O), C in graphite (C-GPH) and Be in beryllium metal (Be-TH)). From MATJEFF31.BOLIB it is easily possible to generate, with the use of the TRANSX code, working libraries of collapsed and self-shielded cross sections in GOXS or FIDO-ANISN format for calculations with the DOORS /12/, DANTSYS /13/ and PARTISN /14/ deterministic transport systems and the MORSE /15/ Monte

  5. Fine-Group Cross Section Library Based on JEFF3.1 for Nuclear Fission Applications.

    SciTech Connect

    ROBERTO,; ORSI,

    2009-10-16

    Version 00 The NJOY-99.160 data processing system was used for the MATJEFF31.BOLIB library generation to assure the consistency with the previous generation of the VITJEFF31.BOLIB /6/ twin library, based on the same GENDF cross section data file. In particular it used a revised version of the GROUPR /7/ module, originally developed in ENEA-Bologna before the free release of an analogous GROUPR revised version with NJOY-99.161, in order to correctly deal with the non-Cartesian interpolation schemes, contained in 69 JEFF-3.1 evaluated nuclear data files. The TRANSX-2.15 /8/ code was then used to obtain the total (prompt + delayed) fission spectra for U-235, U-238 and Pu-239. These data, contained in the MATJEFF31.BOLIB package, are available in tabulated form as in the VITJEFF31.BOLIB library package. On the contrary the VITAMIN-B6, VITJEF22.BOLIB /9/ and MATJEF22.BOLIB /10/ similar library packages contain in tabulated form only the prompt components. MATJEFF31.BOLIB is a pseudo-problem-independent library based on the Bondarenko /11/ (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. The library contains 176 nuclides at 4 temperatures, obtained for the most part with 6 to 8 values for the background cross section. Thermal scattering cross sections were processed at all temperatures available in the JEFF-3.1 thermal scattering law data file for 6 additional bound nuclides (H-1 in light water (H-H2O), H-1 in polyethylene (H-CH2), H-1 in zirconium hydride (H-ZrH) (not contained in VITAMIN-B6, VITJEF22.BOLIB and MATJEF22.BOLIB), H-2 in heavy water (H2-D2O), C in graphite (C-GPH) and Be in beryllium metal (Be-TH)). From MATJEFF31.BOLIB it is easily possible to generate, with the use of the TRANSX code, working libraries of collapsed and self-shielded cross sections in GOXS or FIDO-ANISN format for calculations with the DOORS /12/, DANTSYS /13/ and PARTISN /14/ deterministic transport systems and the MORSE /15/ Monte Carlo

  6. Obstetric interventions in two groups of hospitals in Catalonia: a cross-sectional study

    PubMed Central

    2014-01-01

    Background Childbirth assistance in highly technological settings and existing variability in the interventions performed are cause for concern. In recent years, numerous recommendations have been made concerning the importance of the physiological process during birth. In Spain and Catalonia, work has been carried out to implement evidence-based practices for childbirth and to reduce unnecessary interventions. To identify obstetric intervention rates among all births, determine whether there are differences in interventions among full-term single births taking place in different hospitals according to type of funding and volume of births attended to, and to ascertain whether there is an association between caesarean section or instrumental birth rates and type of funding, the volume of births attended to and women’s age. Methods Cross-sectional study, taking the hospital as the unit of analysis, obstetric interventions as dependent variables, and type of funding, volume of births attended to and maternal age as explanatory variables. The analysis was performed in three phases considering all births reported in the MBDS Catalonia 2011 (7,8570 births), full-term single births and births coded as normal. Results The overall caesarean section rate in Catalonia is 27.55% (CI 27.23 to 27.86). There is a significant difference in caesarean section rates between public and private hospitals in all strata. Both public and private hospitals with a lower volume of births have higher obstetric intervention rates than other hospitals (49.43%, CI 48.04 to 50.81). Conclusions In hospitals in Catalonia, both the type of funding and volume of births attended to have a significant effect on the incidence of caesarean section, and type of funding is associated with the use of instruments during delivery. PMID:24731410

  7. A broad-group cross-section library based on ENDF/B-VII.0 for fast neutron dosimetry Applications

    SciTech Connect

    Alpan, F.A.

    2011-07-01

    A new ENDF/B-VII.0-based coupled 44-neutron, 20-gamma-ray-group cross-section library was developed to investigate the latest evaluated nuclear data file (ENDF) ,in comparison to ENDF/B-VI.3 used in BUGLE-96, as well as to generate an objective-specific library. The objectives selected for this work consisted of dosimetry calculations for in-vessel and ex-vessel reactor locations, iron atom displacement calculations for reactor internals and pressure vessel, and {sup 58}Ni(n,{gamma}) calculation that is important for gas generation in the baffle plate. The new library was generated based on the contribution and point-wise cross-section-driven (CPXSD) methodology and was applied to one of the most widely used benchmarks, the Oak Ridge National Laboratory Pool Critical Assembly benchmark problem. In addition to the new library, BUGLE-96 and an ENDF/B-VII.0-based coupled 47-neutron, 20-gamma-ray-group cross-section library was generated and used with both SNLRML and IRDF dosimetry cross sections to compute reaction rates. All reaction rates computed by the multigroup libraries are within {+-} 20 % of measurement data and meet the U. S. Nuclear Regulatory Commission acceptance criterion for reactor vessel neutron exposure evaluations specified in Regulatory Guide 1.190. (authors)

  8. 69-Group Thermal-Reactor Neutron Cross Section Data from ENDF/B-V in MATXS Format.

    Energy Science and Technology Software Center (ESTSC)

    1985-12-30

    Version: 00 The library contains 80 materials (no photon production) and includes self-shielded cross sections for the important actinides. Thermal scattering data are given for all materials, with bound scattering for the important moderators. The group structure contains 42 thermal groups extending to 4 eV. The data were generated with PSR-171/NJOY-II [2]. The energy group structure for MATXS7A is listed in Table 1, the materials with neutron scattering data in Table 2, and those withmore » thermal scattering data in Table 3.« less

  9. Jet inclusive cross sections

    SciTech Connect

    Del Duca, V.

    1992-11-01

    Minijet production in jet inclusive cross sections at hadron colliders, with large rapidity intervals between the tagged jets, is evaluated by using the BFKL pomeron. We describe the jet inclusive cross section for an arbitrary number of tagged jets, and show that it behaves like a system of coupled pomerons.

  10. Vulnerability to unhealthy behaviours across different age groups in Swedish Adolescents: a cross-sectional study

    PubMed Central

    Paulsson Do, Ulrica; Edlund, Birgitta; Stenhammar, Christina; Westerling, Ragnar

    2014-01-01

    Purpose: There is lack of evidence on the effects of health-promoting programmes among adolescents. Health behaviour models and studies seldom compare the underlying factors of unhealthy behaviours between different adolescent age groups. The main objective of this study was to investigate factors including sociodemographic parameters that were associated with vulnerability to health-damaging behaviours and non-adoption of health-enhancing behaviours in different adolescent age groups. Methods: A survey was conducted among 10,590 pupils in the age groups of 13–14, 15–16 and 17–18 years. Structural equation modelling was performed to determine whether health-damaging behaviours (smoking and alcohol consumption) and non-adoption of health-enhancing behaviours (regular meal habits and physical activity) shared an underlying vulnerability. This method was also used to determine whether gender and socio-economic status were associated with an underlying vulnerability to unhealthy behaviours. Results: The findings gave rise to three models, which may reflect the underlying vulnerability to health-damaging behaviours and non-adoption of health-enhancing behaviours at different ages during adolescence. The four behaviours shared what was interpreted as an underlying vulnerability in the 15–16-year-old age group. In the youngest group, all behaviours except for non-participation in physical activity shared an underlying vulnerability. Similarly, alcohol consumption did not form part of the underlying vulnerability in the oldest group. Lower socio-economic status was associated with an underlying vulnerability in all the age groups; female gender was associated with vulnerability in the youngest adolescents and male gender among the oldest adolescents. Conclusions: These results suggest that intervention studies should investigate the benefits of health-promoting programmes designed to prevent health-damaging behaviours and promote health-enhancing behaviours in

  11. Chronic low back pain patient groups in primary care – A cross sectional cluster analysis

    PubMed Central

    2013-01-01

    Background Due to the heterogeneous nature of chronic low back pain (CLBP), it is necessary to identify patient groups and evaluate treatments within these groups. We aimed to identify groups of patients with CLBP in the primary care setting. Methods We performed a k-means cluster analysis on a large data set (n = 634) of primary care patients with CLBP. Variables of sociodemographic data, pain characteristics, psychological status (i.e., depression, anxiety, somatization), and the patient resources of resilience and coping strategies were included. Results We found three clusters that can be characterized as “pensioners with age-associated pain caused by degenerative diseases”, “middle-aged patients with high mental distress and poor coping resources”, and “middle-aged patients who are less pain-affected and better positioned with regard to their mental health”. Conclusions Our results supported current knowledge concerning groups of CLBP patients in primary care. In particular, we identified a group that was most disabled and distressed, and which was mainly characterized by psychological variables. As shown in our study, pain-related coping strategies and resilience were low in these patients and might be addressed in differentiating treatment strategies. Future studies should focus on the identification of this group in order to achieve effective treatment allocation. Trial registration German Clinical Trial Register DRKS00003123 PMID:24131707

  12. Comparison of Some Risk Factors for Diabetes Across Different Social Groups: A Cross-Sectional Study

    PubMed Central

    Banerjee, A; Rathod, HK; Konda, M; Bhawalkar, JS

    2014-01-01

    Background: In fast, developing economies such as India, the population is undergoing rapid social transition, which can increase the risk profile for diabetes. Market forces promoting lifestyles such as sedentary habits, alcohol and tobacco use, which earlier were more prevalent among affluent urban populations are now trickling into the urban poor and rural populations. Aim: The aim of the present research was to compare the prevalence of risk factors for diabetes among three distinct social groups-the urban affluent, the urban poor and the rural poor. Subjects and Methods: A total of 775 adult population over 18 years and belonging to both genders were surveyed for prevalence of some of the risk factors for diabetes such as physical inactivity, obesity, alcohol, and tobacco use. The sample comprised of three distinct social groups as follows; 125 medical students representing the affluent, 400 subjects from urban slums, and 250 subjects from rural areas. Obesity was measured by body mass index (BMI) while central obesity was ascertained by waist hip ratio (WHR). Alcohol and tobacco use were elicited by interview. Results: The overall response rate was 88.52% (686/775). Medical students were more sedentary with mean hours spent each day sitting or reclining at 10.47 (3.25) h, compared to corresponding figures of 6.34 (3.1) h and 7.49 (3.74) h for the rural and urban slum residents respectively (P < 0.001). However, all types of leisure time physical activities were significantly more among the medical students compared to the other groups (P < 0.001). BMI was significantly highest among the rural population with mean of 24.22 (4.17) kg/m2 when compared to the other groups, (P < 0.001). Villagers also had higher WHR and had a higher proportion of persons above the WHR cut-off for gender (P < 0.001). Experimentation with alcohol was more prevalent among the medical students while the urban slum residents were more frequent and heavy drinkers. Smoking was most

  13. Determinants of caregivers’ vaccination intention with respect to child age group: a cross-sectional survey in South Korea

    PubMed Central

    Paek, Hye-Jin; Shin, Kyung-Ah; Park, Kisoo

    2015-01-01

    Objective This study examined how knowledge, risk perception, health beliefs and multidimensional health locus of control (HLC) were associated with caregivers’ intention to vaccinate their child, and how these associations varied across child age groups. Setting South Korea. Methods The cross-sectional survey was conducted via a face-to-face interview among 1017 nationally representative caregivers who had children aged 12 or younger. The outcome variable was caregivers’ intention to vaccinate their children. Results Hierarchical regression analysis indicated that risk perception was negatively associated with vaccination intention only among the age group 4–6 (β=−0.127, p<0.05). Perceived benefit was the only significant predictor of the outcome variables for all three age groups. In contrast, perceived barrier was negatively related to vaccination intention only among the age group 7–12 (β=−0.104, p<0.05). Internal HLC was positively related to vaccination intention only among the age group 7–12 (β=0.151, p<0.001), while chance HLC was negatively related to vaccination intention only among the age group 0–3 (β=−0.121, p<0.05). Conclusions This study identifies key vaccination intention determinants that are differentially associated with caregivers’ children's age groups. To improve vaccination rates, it suggests the need for strategies tailored to children's age. PMID:26408283

  14. Internet addiction in a group of medical students: a cross sectional study.

    PubMed

    Pramanik, T; Sherpa, M T; Shrestha, R

    2012-03-01

    The use of Internet for education, recreation and communication is increasing day by day. Nevertheless, the possibility of exploitation and addiction leading to impairment in academic performance and emotional balance cannot be denied, especially among young population. The study was aimed to measure the degree of Internet addiction among a group of medical students. Internet addiction test questionnaire developed by Young was used to assess mild, moderate and severe addiction. Amongst the study population (n=130, age 19-23 years), 40% had mild addiction. Moderate and severe addiction was found in 41.53% and 3.07% of the participants respectively. The study revealed that 24% often and 19.2% always found themselves using Internet longer than they had planned or thought. Late night Internet surfing leading to sleep deprivation was found in 31.53% of the participants. Almost one fourth of them (25.38%) occasionally tried to cut down the time they spent on the Internet but failed and 31.53% sometimes experienced restlessness when deprived of Internet access. Results reflected that a significant number of participants suffered from mild to moderate addiction. The role of counseling and education should be emphasized for prevention of Internet addiction. PMID:23441494

  15. Measurement and Basic Physics Committee of the U.S. Cross-Section Evaluation Working Group annual report 1997

    SciTech Connect

    Smith, D.L.; McLane, V.

    1997-10-01

    The Cross-Section Evaluation Working Group (CSEWG) is a long-standing committee charged with responsibility for organizing and overseeing the US cross-section evaluation effort. It`s main product is the official US evaluated nuclear data file, ENDF. In 1992 CSEWG added the Measurements Committee to its list of standing committees and subcommittees. This action was based on a recognition of the importance of experimental data in the evaluation process as well as the realization that measurement activities in the US were declining at an alarming rate and needed considerable encouragement to avoid the loss of this resource. The mission of the Committee is to maintain contact with experimentalists in the Us and to encourage them to contribute to the national nuclear data effort. Improved communication and the facilitation of collaborative activities are among the tools employed in achieving this objective. In 1994 the Committee was given an additional mission, namely, to serve as an interface between the applied interests represented in CSEWG and the basic nuclear science community. Accordingly, its name was changed to the Measurement and Basic Physics Committee. The present annual report is the third such document issued by the Committee. It contains voluntary contributions from several laboratories in the US. Their contributions were submitted to the Chairman for compilation and editing.

  16. One-group fission cross sections for plutonium and minor actinides inserted in calculated neutron spectra of fast reactor cooled with lead-208 or lead-bismuth eutectic

    SciTech Connect

    Khorasanov, G. L.; Blokhin, A. I.

    2012-07-01

    The paper is dedicated to one-group fission cross sections of Pu and MA in LFRs spectra with the aim to increase these values by choosing a coolant which hardens neutron spectra. It is shown that replacement of coolant from Pb-Bi with Pb-208 in the fast reactor RBEC-M, designed in Russia, leads to increasing the core mean neutron energy. As concerns fuel Pu isotopes, their one-group fission cross sections become slightly changed, while more dramatically Am-241 one-group fission cross section is changed. Another situation occurs in the lateral blanket containing small quantities of minor actinides. It is shown that as a result of lateral blanket mean neutron energy hardening the one-group fission cross sections of Np-237, Am-241 and Am-243 increases up to 8-11%. This result allows reducing the time of minor actinides burning in FRs. (authors)

  17. Trials of large group teaching in Malaysian private universities: a cross sectional study of teaching medicine and other disciplines

    PubMed Central

    2011-01-01

    Background This is a pilot cross sectional study using both quantitative and qualitative approach towards tutors teaching large classes in private universities in the Klang Valley (comprising Kuala Lumpur, its suburbs, adjoining towns in the State of Selangor) and the State of Negeri Sembilan, Malaysia. The general aim of this study is to determine the difficulties faced by tutors when teaching large group of students and to outline appropriate recommendations in overcoming them. Findings Thirty-two academics from six private universities from different faculties such as Medical Sciences, Business, Information Technology, and Engineering disciplines participated in this study. SPSS software was used to analyse the data. The results in general indicate that the conventional instructor-student approach has its shortcoming and requires changes. Interestingly, tutors from Medicine and IT less often faced difficulties and had positive experience in teaching large group of students. Conclusion However several suggestions were proposed to overcome these difficulties ranging from breaking into smaller classes, adopting innovative teaching, use of interactive learning methods incorporating interactive assessment and creative technology which enhanced students learning. Furthermore the study provides insights on the trials of large group teaching which are clearly identified to help tutors realise its impact on teaching. The suggestions to overcome these difficulties and to maximize student learning can serve as a guideline for tutors who face these challenges. PMID:21902839

  18. Measurement and Basic Physics Committee of the US cross-section evaluation working group. Annual report 1996

    SciTech Connect

    Smith, D.L.; McLane, V.

    1996-11-01

    The Cross-Section Evaluation Working Group (CSEWG) is a long-standing committee charged with the responsibility for organizing and overseeing the U.S. cross-section evaluation effort. It`s main product is the official U.S. evaluated nuclear data file, ENDF. The current version of this file is Version VI. All evaluations included in ENDF are reviewed and approved by CSEWG and issued by the U.S. Nuclear Data Center, Brookhaven National Laboratory. CSEWG is comprised of volunteers from the U.S. nuclear data community who possess expertise in evaluation methodologies and who collectively have been responsible for producing most of the evaluations included in ENDF. In 1992 CSEWG added the Measurements Committee to its list of standing committees and subcommittees. This action was based on a recognition of the importance of experimental data in the evaluation process as well as the realization that measurement activities in the U.S. were declining at an alarming rate and needed all possible encouragement to avoid the loss of this resource. The mission of the Committee is to maintain a network of experimentalists in the U.S. that would provide needed encouragement to the national nuclear data measurement effort through improved communication and facilitation of collaborative activities. In 1994, an additional charge was added to the responsibilities of this Committee, namely, to serve as an interface between the more applied interests represented in CSEWG and the basic nuclear science community. This annual report is the second such document issued by the Committee. It contains voluntary contributions from eleven laboratories in the U.S. which have been prepared by members of the Committee and submitted to the Chairman for compilation and editing. It is hoped that the information provided here on the work that is going on at the reporting laboratories will prove interesting and stimulating to the readers.

  19. MEASUREMENT AND BASIC PHYSICS COMMITTEE OF THE U.S. CROSS-SECTION EVALUATION WORKING GROUP, ANNUAL REPORT 1997

    SciTech Connect

    SMITH,D.L.; MCLANE,V.

    1998-10-20

    The Cross-Section Evaluation Working Group (CSEWG) is a long-standing committee charged with responsibility for organizing and overseeing the US cross-section evaluation effort. Its main product is the official US evaluated nuclear data file, ENDF. The current version of this file is Version VI. All evaluations included in ENDF, as well as periodic modifications and updates to the file, are reviewed and approved by CSEWG and issued by the US Nuclear Data Center, Brookhaven National Laboratory. CSEWG is comprised of volunteers from the US nuclear data community who possess expertise in evaluation methodologies and who collectively have been responsible for producing most of the evaluations included in ENDF. In 1992 CSEWG added the Measurements Committee to its list of standing committees and subcommittees. This action was based on a recognition of the importance of experimental data in the evaluation process as well as the realization that measurement activities in the US were declining at an alarming rate and needed considerable encouragement to avoid the loss of this resource. The mission of the Committee is to maintain contact with experimentalists in the US and to encourage them to contribute to the national nuclear data effort. Improved communication and the facilitation of collaborative activities are among the tools employed in achieving this objective. In 1994 the Committee was given an additional mission, namely, to serve as an interface between the applied interests represented in CSEWG and the basic nuclear science community. Accordingly, its name was changed to the Measurement and Basic Physics Committee. The present annual report is the third such document issued by the Committee. It contains voluntary contributions from several laboratories in the US. Their contributions were submitted to the Chairman for compilation and editing.

  20. Validation of nuclear criticality safety software and 27 energy group ENDF/B-IV cross sections. Revision 1

    SciTech Connect

    Lee, B.L. Jr.; D`Aquila, D.M.

    1996-01-01

    The original validation report, POEF-T-3636, was documented in August 1994. The document was based on calculations that were executed during June through August 1992. The statistical analyses in Appendix C and Appendix D were completed in October 1993. This revision is written to clarify the margin of safety being used at Portsmouth for nuclear criticality safety calculations. This validation gives Portsmouth NCS personnel a basis for performing computerized KENO V.a calculations using the Lockheed Martin Nuclear Criticality Safety Software. The first portion of the document outlines basic information in regard to validation of NCSS using ENDF/B-IV 27-group cross sections on the IBM3090 at ORNL. A basic discussion of the NCSS system is provided, some discussion on the validation database and validation in general. Then follows a detailed description of the statistical analysis which was applied. The results of this validation indicate that the NCSS software may be used with confidence for criticality calculations at the Portsmouth Gaseous Diffusion Plant. For calculations of Portsmouth systems using the specified codes and systems covered by this validation, a maximum k{sub eff} including 2{sigma} of 0.9605 or lower shall be considered as subcritical to ensure a calculational margin of safety of 0.02. The validation of NCSS on the IBM 3090 at ORNL was extended to include NCSS on the IBM 3090 at K-25.

  1. Association between quality management and performance indicators in Dutch diabetes care groups: a cross-sectional study

    PubMed Central

    Campmans-Kuijpers, Marjo J E; Baan, Caroline A; Lemmens, Lidwien C; Klomp, Maarten L H; Romeijnders, Arnold C M; Rutten, Guy E H M

    2015-01-01

    Objectives To enhance the quality of diabetes care in the Netherlands, so-called care groups with three to 250 general practitioners emerged to organise and coordinate diabetes care. This introduced a new quality management level in addition to the quality management of separate general practices. We hypothesised that this new level of quality management might be associated with the aggregate performance indicators on the patient level. Therefore, we aimed to explore the association between quality management at the care group level and its aggregate performance indicators. Design A cross-sectional study. Setting All Dutch care groups (n=97). Participants 23 care groups provided aggregate register-based performance indicators of all their practices as well as data on quality management measured with a questionnaire filled out by 1 or 2 of their quality managers. Primary outcomes The association between quality management, overall and in 6 domains (‘organisation of care’, ‘multidisciplinary teamwork’, ‘patient centredness’, ‘performance management’, ‘quality improvement policy’ and ‘management strategies’) on the one hand and 3 process indicators (the percentages of patients with at least 1 measurement of glycated haemoglobin, lipid profile and systolic blood pressure), and 3 intermediate outcome indicators (the percentages of patients with glycated haemoglobin below 53 mmol/mol (7%); low-density lipoprotein cholesterol below 2.5 mmol/L; and systolic blood pressure below 140 mm Hg) by weighted univariable linear regression. Results The domain ‘management strategies’ was significantly associated with the percentage of patients with a glycated haemoglobin <53 mmol/mol (β 0.28 (0.09; 0.46) p=0.01) after correction for multiple testing. The other domains as well as overall quality management were not associated with aggregate process or outcome indicators. Conclusions This first exploratory study on quality management showed weak

  2. Attitudes About Sexual Activity Among Postmenopausal Women in Different Ethnic Groups: A Cross-sectional Study in Jahrom, Iran

    PubMed Central

    Jamali, Safieh; Javadpour, Shohreh; Mosalanejad, Leili; Parnian, Razieh

    2016-01-01

    Background: Sexual function is affected by personal and interpersonal factors, familial and social traditions, culture, religion, menopause, and aging. So, ethnicity is a determining factor in sexual function. The present study aimed to investigate the prevalence of sexual dysfunction and attitudes towards sexuality in postmenopausal women among three different ethnic groups in Iran. Methods: This cross-sectional study was conducted on 746 postmenopausal women between 50 and 89 years who referred to Honoree clinic, Jahrom in 2013. Among the study participants, 42.4% were Arab, 33.5% were Persian, and 24.1% were Lor. Data were collected about women's socio-demographic characteristics, attitudes regarding sexuality and sexual function. The descriptive statistics were used for demographic variables. Moreover, ANOVA, post hoc (LSD) was used. Besides, p<0.05 was considered statistically significant. Results: The participants' mean age was 60.10±6.89 years and the total mean score of Female Sexual Function Index (FSFI) was 19.31±8.5. In addition, 81.5% of the women had sexual dysfunction (FSFI <26.55) and only 147 women (18.5%) had normal sexual function (FSFI >26.55). Sexual dysfunction was 75.3% in Arabs, 83.2% in Persians, and 86.1% in Lors. Besides, the most prevalent sexual dysfunction was dyspareunia in Arabs and arousal disorder in Persians and Lors. Conclusion: The results of this study showed that sexual dysfunction is considerable among postmenopausal women. The most prevalent sexual dysfunction was dyspareunia in Arabs and arousal disorder in Persians and Lors. PMID:26962483

  3. CSEWG SYMPOSIUM, A CSWEG RETROSPECTIVE. 35TH ANNIVERSARY CROSS SECTION EVALUATION WORKING GROUP, NOV. 5, 2001, BROOKHAVEN NATIONAL LABORATORY.

    SciTech Connect

    DUNFORD, C.; HOLDEN, N.; PEARLSTEIN, S.

    2001-11-05

    This publication has been prepared to record some of the history of the Cross Section Evaluation Working Group (CSEWG). CSEWG is responsible for creating the evaluated nuclear data file (ENDF/B) which is widely used by scientists and engineers who are involved in the development and maintenance of applied nuclear technologies. This organization has become the model for the development of nuclear data libraries throughout the world. The data format (ENDF) has been adopted as the international standard. On November 5, 2001, a symposium was held at Brookhaven National Laboratory to celebrate the 50 th meeting of the CSEWG organization and the 35 th anniversary of its first meeting in November 1966. The papers presented in this volume were prepared by present and former CSEWG members for presentation at the November 2001 symposium. All but two of the presentations are included. I have included an appendix to list all of the CSEWG members and their affiliations, which has been compiled from the minutes of each of the CSEWG meetings. Minutes exist for all meetings except the 4 th meeting held in January 1968. The list includes 348 individuals from 71 organizations. The dates for each of the 50 CSEWG meetings are listed. The committee structure and chairmen of all committees and subcommittees are also included in the appendix. This volume is dedicated to three individuals whose foresight and talents made CSEWG possible and successful. They are Henry Honeck who lead the effort to develop the ENDF format and the CSEWG system, Ira Zartman, the Atomic Energy Commission program manager who provided the programmatic direction and support, and Sol Pearlstein who led the development of the CESWG organization and the ENDF/B evaluated nuclear data library.

  4. Processing and validation of JEFF-3.1.1 and ENDF/B-VII.0 group-wise cross section libraries for shielding calculations

    NASA Astrophysics Data System (ADS)

    Pescarini, M.; Sinitsa, V.; Orsi, R.; Frisoni, M.

    2013-03-01

    This paper presents a synthesis of the ENEA-Bologna Nuclear Data Group programme dedicated to generate and validate group-wise cross section libraries for shielding and radiation damage deterministic calculations in nuclear fission reactors, following the data processing methodology recommended in the ANSI/ANS-6.1.2-1999 (R2009) American Standard. The VITJEFF311.BOLIB and VITENDF70.BOLIB finegroup coupled n-γ (199 n + 42 γ - VITAMIN-B6 structure) multi-purpose cross section libraries, based on the Bondarenko method for neutron resonance self-shielding and respectively on JEFF-3.1.1 and ENDF/B-VII.0 evaluated nuclear data, were produced in AMPX format using the NJOY-99.259 and the ENEA-Bologna 2007 Revision of the SCAMPI nuclear data processing systems. Two derived broad-group coupled n-γ (47 n + 20 γ - BUGLE-96 structure) working cross section libraries in FIDO-ANISN format for LWR shielding and pressure vessel dosimetry calculations, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, were generated by the revised version of SCAMPI, through problem-dependent cross section collapsing and self-shielding from the cited fine-group libraries. The validation results on the criticality safety benchmark experiments for the fine-group libraries and the preliminary validation results for the broad-group working libraries on the PCA-Replica and VENUS-3 engineering neutron shielding benchmark experiments are reported in synthesis.

  5. Radar cross section of insects

    NASA Astrophysics Data System (ADS)

    Riley, J. R.

    1985-02-01

    X-band measurements of radar cross section as a function of the angle between insect body axis and the plane of polarization are presented. A finding of particular interest is that in larger insects, maximum cross section occurs when the E-vector is perpendicular to the body axis. A new range of measurements on small insects (aphids, and planthoppers) is also described, and a comprehensive summary of insect cross-section data at X-band is given.

  6. Brominated 7-hydroxycoumarin-4-ylmethyls: Photolabile protecting groups with biologically useful cross-sections for two photon photolysis

    PubMed Central

    Furuta, Toshiaki; Wang, Samuel S.-H.; Dantzker, Jami L.; Dore, Timothy M.; Bybee, Wendy J.; Callaway, Edward M.; Denk, Winfried; Tsien, Roger Y.

    1999-01-01

    Photochemical release (uncaging) of bioactive messengers with three-dimensional spatial resolution in light-scattering media would be greatly facilitated if the photolysis could be powered by pairs of IR photons rather than the customary single UV photons. The quadratic dependence on light intensity would confine the photolysis to the focus point of the laser, and the longer wavelengths would be much less affected by scattering. However, previous caged messengers have had very small cross sections for two-photon excitation in the IR region. We now show that brominated 7-hydroxycoumarin-4-ylmethyl esters and carbamates efficiently release carboxylates and amines on photolysis, with one- and two-photon cross sections up to one or two orders of magnitude better than previously available. These advantages are demonstrated on neurons in brain slices from rat cortex and hippocampus excited by glutamate uncaged from N-(6-bromo-7-hydroxycoumarin-4-ylmethoxycarbonyl)-l-glutamate (Bhc-glu). Conventional UV photolysis of Bhc-glu requires less than one-fifth the intensities needed by one of the best previous caged glutamates, γ-(α-carboxy-2-nitrobenzyl)-l-glutamate (CNB-glu). Two-photon photolysis with raster-scanned femtosecond IR pulses gives the first three-dimensionally resolved maps of the glutamate sensitivity of neurons in intact slices. Bhc-glu and analogs should allow more efficient and three-dimensionally localized uncaging and photocleavage, not only in cell biology and neurobiology but also in many technological applications. PMID:9990000

  7. XCOM: Photon Cross Sections Database

    National Institute of Standards and Technology Data Gateway

    SRD 8 XCOM: Photon Cross Sections Database (Web, free access)   A web database is provided which can be used to calculate photon cross sections for scattering, photoelectric absorption and pair production, as well as total attenuation coefficients, for any element, compound or mixture (Z <= 100) at energies from 1 keV to 100 GeV.

  8. The total charm cross section

    SciTech Connect

    Vogt, R

    2007-09-14

    We assess the theoretical uncertainties on the total charm cross section. We discuss the importance of the quark mass, the scale choice and the parton densities on the estimate of the uncertainty. We conclude that the uncertainty on the total charm cross section is difficult to quantify.

  9. o-nitrobenzyl photolabile protecting groups with red-shifted absorption: syntheses and uncaging cross-sections for one- and two-photon excitation.

    PubMed

    Aujard, Isabelle; Benbrahim, Chouaha; Gouget, Marine; Ruel, Odile; Baudin, Jean-Bernard; Neveu, Pierre; Jullien, Ludovic

    2006-09-01

    We evaluated the o-nitrobenzyl platform for designing photolabile protecting groups with red-shifted absorption that could be photolyzed upon one- and two-photon excitation. Several synthetic pathways to build different conjugated o-nitrobenzyl backbones, as well as to vary the benzylic position, are reported. Relative to the reference 4,5-dimethoxy-2-nitrobenzyl group, several o-nitrobenzyl derivatives exhibit a large and red-shifted one-photon absorption within the near-UV range. Uncaging after one-photon excitation was studied by measuring UV-visible absorption and steady-state fluorescence emission on model caged ethers and esters. In the whole series investigated, the caged substrates were released cleanly upon photolysis. Quantum yields of uncaging after one-photon absorption lie within the 0.1-1 % range. We observed that these drop as the maximum wavelength absorption of the o-nitrobenzyl protecting group is increased. A new method based on fluorescence correlation spectroscopy (FCS) after two-photon excitation was used to measure the action uncaging cross section for two-photon excitation. The series of o-nitrobenzyl caged fluorescent coumarins investigated exhibit values within the 0.1-0.01 Goeppert-Mayer (GM) range. Such results are in line with the low quantum yields of uncaging associated with cross-sections of 1-50 GM for two-photon absorption. Although the cross-sections for one- and two-photon absorption of o-nitrobenzyl photolabile protecting groups can be readily improved, we emphasize the difficulty in enlarging the corresponding action uncaging cross-sections in view of the observed trend of their quantum yield of uncaging. PMID:16763952

  10. Sensitisation to mites in a group of patients with asthma in Yaounde, Cameroon: a cross-sectional study

    PubMed Central

    Pefura-Yone, Eric Walter; Kengne, André Pascal; Kuaban, Christopher

    2014-01-01

    Objectives Sensitisation of asthmatic patients to mites in sub-Saharan Africa has been less described. The aim of this study was to assess the prevalence and determinants of sensitisation to mites in asthmatic adolescents and adults in Yaounde, Cameroon. Design This was a cross-sectional study. Logistic regression models were employed to investigate the determinants of sensitisation to mites. Setting This study was carried out at the Jamot Hospital and CEDIMER private centre, in Yaounde, capital city of Cameroon. Participants All asthmatic patients received in consultations from January 2012 to June 2013 and in whom prick-skin tests for perennial aeroallergens were performed were included. Outcome measures Prevalence of sensitisation to mites and associated factors. Results In total, 201 patients (132 being women, 65.7%), with a median age of 36 (25th–75th centiles: 20–54) years were included, with 135 (67.2%) having a positive skin test for mites. Sensitisation to Dermatophagoïdes pteronyssinus, Dermatophagoides farinae and Blomia tropicalis was found in 53.2%, 49.8% and 47.8% of the patients, respectively. Intermittent rhinitis (16.3% vs 7.6%) and persistent rhinitis (43.0% vs 22.7%) were more frequent in sensitised patients than in the non-sensitised ones (p<0.010). Independent allergological determinants of sensitisation to mites were sensitisation to Alternaria alternata (adjusted OR 14.98 (95% CIs 1.96 to 114.4)) and sensitisation to Blattella germanica (3.48 (1.34 to 9.00)). Conclusions Sensitisation to mites was found in about two-thirds of asthmatic patients in this setting, with a frequent multiple sensitisations to A alternata and Blattella germanica. Systematically investigating asthmatic patients for mites' sensitisation and determinants will help optimising the care in this setting by combining the aetiological treatment for the allergy with symptomatic treatment for asthma, in order to modify the natural course of the disease. PMID:24390384

  11. Cross sections at hadron colliders

    SciTech Connect

    Paige, F.E.

    1982-01-01

    The predicted cross sections are given for new Z'/sup 0/ bosons, for the Drell-Yan continuum of ..mu../sup +/..mu../sup -/ pairs, for high p/sub T/ hadron jets, for high p/sub T/ single photons, and for the associated production of heavy quarks. These processes have been selected not to cover the most interesting physics, but to provide a representative selection of cross sections for which to compare various energies and luminosities.

  12. 242Amm fission cross section

    NASA Astrophysics Data System (ADS)

    Browne, J. C.; White, R. M.; Howe, R. E.; Landrum, J. H.; Dougan, R. J.; Dupzyk, R. J.

    1984-06-01

    The neutron-induced fission cross section of 242Amm has been measured over the energy region from 10-3 eV to ~20 MeV in a series of experiments utilizing a linac-produced "white" neutron source and a monoenergetic source of 14.1 MeV neutrons. The cross section was measured relative to that of 235U in the thermal (0.001 to ~3 eV) and high energy (1 keV to ~20 MeV) regions and normalized to the ENDF/B-V 235U(n,f) evaluated cross section. In the resonance energy region (0.5 eV to 10 keV) the neutron flux was measured using thin lithium glass scintillators and the relative cross section thus obtained was normalized to the thermal energy measurement. This procedure allowed a consistency check between the thermal and high energy data. The cross section data have a statistical accuracy of ~0.5% at thermal energies and in the 1-MeV energy region, and a systematic uncertainty of ~5%. We confirmed that 242Amm has the largest thermal fission cross section known with a 2200 m/sec value of 6328 b. Results of a Breit-Wigner sum-of-single-levels analysis of 48 fission resonances up to 20 eV are presented and the connection of these resonance properties to the large thermal cross section is discussed. Our measurements are compared with previously reported results.

  13. Assessment of Degree of Applicability of Benchmarks for Gadolinium Using KENO V.a and the 238-Group SCALE Cross-Section Library

    SciTech Connect

    Goluoglu, S.

    2003-12-01

    A review of the degree of applicability of benchmarks containing gadolinium using the computer code KENO V.a and the gadolinium cross sections from the 238-group SCALE cross-section library has been performed for a system that contains {sup 239}Pu, H{sub 2}O, and Gd{sub 2}O{sub 3}. The system (practical problem) is a water-reflected spherical mixture that represents a dry-out condition on the bottom of a sludge receipt and adjustment tank around steam coils. Due to variability of the mixture volume and the H/{sup 239}Pu ratio, approximations to the practical problem, referred to as applications, have been made to envelop possible ranges of mixture volumes and H/{sup 239}Pu ratios. A newly developed methodology has been applied to determine the degree of applicability of benchmarks as well as the penalty that should be added to the safety margin due to insufficient benchmarks.

  14. Association of ABO Blood Group and Rh factor with Periodontal Disease in a Population of Virajpet, Karnataka: A Cross-Sectional Study

    PubMed Central

    Vivek, S; Jain, Jithesh; Simon, Sequiera Peter; Battur, Hemanth; Supreetha, S; Haridas, Reshmi

    2013-01-01

    Background: The purpose of the present study was to determine whether there was an association between periodontal diseases and ABO blood groups. Materials & Methods: An epidemiological study was was carried out on 220 subjects who were randomly selected from individuals referred for periodontal treatment or for other reasons regarding Oral health at Coorg Institute of Dental Sciences. Results: The findings of our study revealed that subject’s blood group O (65.8) and Rh positive (73.33%) had a greater propensity for periodontitis. Conclusion: The results of the present study revealed blood groups and Rh factor can act as a determinant of periodontitis. How to cite this article: Vivek S, Jain J, Simon SP, Battur H, Supreetha S, Haridas R. Association of ABO Blood Group and Rh factor with Periodontal Disease in a Population of Virajpet, Karnataka: A Cross-Sectional Study. J Int Oral Health 2013; 5(4):30-34. PMID:24155617

  15. Accurate Cross Sections for Microanalysis

    PubMed Central

    Rez, Peter

    2002-01-01

    To calculate the intensity of x-ray emission in electron beam microanalysis requires a knowledge of the energy distribution of the electrons in the solid, the energy variation of the ionization cross section of the relevant subshell, the fraction of ionizations events producing x rays of interest and the absorption coefficient of the x rays on the path to the detector. The theoretical predictions and experimental data available for ionization cross sections are limited mainly to K shells of a few elements. Results of systematic plane wave Born approximation calculations with exchange for K, L, and M shell ionization cross sections over the range of electron energies used in microanalysis are presented. Comparisons are made with experimental measurement for selected K shells and it is shown that the plane wave theory is not appropriate for overvoltages less than 2.5 V. PMID:27446747

  16. International Evaluation of Neutron Cross Section Standards

    NASA Astrophysics Data System (ADS)

    Carlson, A. D.; Pronyaev, V. G.; Smith, D. L.; Larson, N. M.; Chen, Zhenpeng; Hale, G. M.; Hambsch, F.-J.; Gai, E. V.; Oh, Soo-Youl; Badikov, S. A.; Kawano, T.; Hofmann, H. M.; Vonach, H.; Tagesen, S.

    2009-12-01

    Neutron cross section standards are the basis for the determination of most neutron cross sections. They are used for both measurements and evaluations of neutron cross sections. Not many cross sections can be obtained absolutely - most cross sections are measured relative to the cross section standards and converted using evaluations of the standards. The previous complete evaluation of the neutron cross section standards was finished in 1987 and disseminated as the NEANDC/INDC and ENDF/B-VI standards. R-matrix model fits for the light elements and non-model least-squares fits for all the cross sections in the evaluation were the basis of the combined fits for all of the data. Some important reactions and constants are not standards, but they assist greatly in the determination of the standard cross sections and reduce their uncertainties - these data were also included in the combined fits. The largest experimental database used in the evaluation was prepared by Poenitz and included about 400 sets of experimental data with covariance matrices of uncertainties that account for all cross-energy, cross-reaction and cross-material correlations. For the evaluation GMA, a least-squares code developed by Poenitz, was used to fit all types of cross sections (absolute and shape), their ratios, spectrum-averaged cross sections and thermal constants in one full analysis. But, the uncertainties derived in this manner, and especially those obtained in the R-matrix model fits, have been judged to be too low and unrealistic. These uncertainties were substantially increased prior to their release in the recommended data files of 1987. Modified percentage uncertainties were reassigned by the United States Cross Section Evaluation Working Group's Standards Subcommittee for a wide range of energies, and no covariance (or correlation) matrices were supplied at that time. The need to re-evaluate the cross section standards is based on the appearance of a significant amount of precise

  17. Low Energy Neutrino Cross Sections: Data from DOE laboratory experiments as compiled in data reviews by the Durham High Energy Physics Database Group

    DOE Data Explorer

    This large collection of low-energy (less than 30 GEV) neutrino cross sections is extracted from the results of many experiments from 1973 through 2002. The experiments, facilities, and collaborations include ANL, BNL, and FNAL in the U.S., along with CERN, Gargamelle, SKAT, LSND, and others. The data are presented in both tabular and plotted formats. The Durham High Energy Physics Database Group makes these data available in one place, easy to access and compare. The data are also included in the Durham HEP Reaction Data Database, which can be searched at http://hepdata.cedar.ac.uk/reaction

  18. A nuclear cross section data handbook

    SciTech Connect

    Fisher, H.O.M.

    1989-12-01

    Isotopic information, reaction data, data availability, heating numbers, and evaluation information are given for 129 neutron cross-section evaluations, which are the source of the default cross sections for the Monte Carlo code MCNP. Additionally, pie diagrams for each nuclide displaying the percent contribution of a given reaction to the total cross section are given at 14 MeV, 1 MeV, and thermal energy. Other information about the evaluations and their availability in continuous-energy, discrete-reaction, and multigroup forms is provided. The evaluations come from ENDF/B-V, ENDL85, and the Los Alamos Applied Nuclear Science Group T-2. Graphs of all neutron and photon production cross-section reactions for these nuclides have been categorized and plotted. 21 refs., 5 tabs.

  19. Neutrino cross-sections: Experiments

    SciTech Connect

    Sánchez, F.

    2015-07-15

    Neutrino-nucleus cross-sections are as of today the main source of systematic errors for oscillation experiments together with neutrino flux uncertainties. Despite recent experimental and theoretical developments, future experiments require even higher precisions in their search of CP violation. We will review the experimental status and explore possible future developments required by next generation of experiments.

  20. Sedimentological cross section of Cambro-Ordovician carbonate shelf (Knox group, Conassauga Formation) in central Alabama: facies, diagenesis, potential reservoirs

    SciTech Connect

    Sternbach, L.R.

    1984-04-01

    Cambro-Ordovician thrust-imbricated carbonates in central Alabama are the focus of renewed exploration interest. Samples from east-west-trending core holes within the surface-most thrust plates reconstruct the carbonate shelf and shelf-edge facies before deformation. The Upper Cambrian shelf margin now is in the subsurface of Talledega County; coeval dolostones in the western part of the state represent the former shelf interior. Rock analogs to former environments include the following. (1) Barrier shoals (Conasauga Formation) - dark colored, partially dolomitized ooid and skeletal grainstones. (2) Submerged back-barrier and offshelf dolomitized sediments (lower Knox Group) - western belt: finely crystalline algal thrombolites, fenestral dolopelmicrites, rippled beds; eastern belt: finely laminated dolostones, slope-derived pebbles and graded beds. (3) Tidal flats (upper Knox Group) - light-colored, crystalline dolostones, dolomitized pellet grainstones, algal laminites, pseudomorphs after sulfates and early diagenetic chertification. (4) Former emergent shelf -(Knox unconformity)-pelmicrite, skeletal wackestones, erosional chert pebble conglomerate. Multiple possibilities for hydrocarbon reservoirs appear throughout the sequence. Vuggy and intercrystalline dolostone porosity is primarily in the lower Knox formations. Primary interparticle pores are retained in lower Knox algal buildups. Breccia porosity occurs in the strata below the Knox unconformity through solution of the underlying Knox Group. Fractures in the subsurface are believed to enhance permeability in all porosity types.

  1. Sedimentological cross section of Cambro-Ordovician carbonate shelf (Knox group, Conasauga Formation) in central Alabama: facies, diagenesis, potential reservoirs

    SciTech Connect

    Sternbach, L.R.

    1984-04-01

    Cambro-Ordovician thrust-imbricated carbonates in central Alabama are the focus of renewed exploration interest. Samples from east-west-trending core holes within the surface-most thrust plates reconstruct the carbonate shelf and shelf-edge facies before deformation. The Upper Cambrian shelf margin now is in the subsurface of Talledega County; coeval dolostones in the western part of the state represent the former shelf interior. Rock analogs to former environments include the following. (1) Barrier shoals (Conasauga Formation) - dark colored, partially dolomitized ooid and skeletal grainstones. (2) Submerged back-barrier and offshelf dolomitized sediments (lower Knox Group) - western belt: finely crystalline algal thrombolites, fenestral dolopelmicrites, rippled beds; eastern belt: finely laminated dolostones, slope-derived pebbles and graded beds. (3) Tidal flats (upper Knox Group) - light-colored, crystalline dolostones, dolomitized pellet grainstones, algal laminites, pseudomorphs after sulfates and early diagenetic chertification. (4) Former emergent shelf -(Knox unconformity)-pelmicrite, skeletal wackestones, erosional chert pebble conglomerate. Multiple possibilities for hydrocarbon reservoirs appear throughout the sequence. Vuggy and intercrystalline dolostone porosity is primarily in the lower Knox formations. Primary interparticle pores are retained in lower Knox algal buildups. Breccia porosity occurs in the strata below the Knox unconformity through solution of the underlying Knox Group. Fractures in the subsurface are believed to enhance permeability in all porosity types.

  2. Unintended consequences of cigarette price changes for alcohol drinking behaviors across age groups: evidence from pooled cross sections

    PubMed Central

    2012-01-01

    Background Raising prices through taxation on tobacco and alcohol products is a common strategy to raise revenues and reduce consumption. However, taxation policies are product specific, focusing either on alcohol or tobacco products. Several studies document interactions between the price of cigarettes and general alcohol use and it is important to know whether increased cigarette prices are associated with varying alcohol drinking patterns among different population groups. To inform policymaking, this study investigates the association of state cigarette prices with smoking, and current, binge, and heavy drinking by age group. Methods The 2001-2006 Behavioral Risk Factor Surveillance System surveys (n = 1,323,758) were pooled and analyzed using multiple regression equations to estimate changes in smoking and drinking pattern response to an increase in cigarette price, among adults aged 18 and older. For each outcome, a multiple linear probability model was estimated which incorporated terms interacting state cigarette price with age group. State and year fixed effects were included to control for potential unobserved state-level characteristics that might influence smoking and drinking. Results Increases in state cigarette prices were associated with increases in current drinking among persons aged 65 and older, and binge and heavy drinking among persons aged 21-29. Reductions in smoking were found among persons aged 30-64, drinking among those aged 18-20, and binge drinking among those aged 65 and older. Conclusions Increases in state cigarette prices may increase or decrease smoking and harmful drinking behaviors differentially by age. Adults aged 21-29 and 65 and older are more prone to increased drinking as a result of increased cigarette prices. Researchers, practitioners, advocates, and policymakers should work together to understand and prepare for these unintended consequences of tobacco taxation policy. PMID:22784412

  3. Path forward for dosimetry cross sections

    SciTech Connect

    Griffin, P.J.; Peters, C.D.

    2011-07-01

    In the 1980's the dosimetry community embraced the need for a high fidelity quantification of uncertainty in nuclear data used for dosimetry applications. This led to the adoption of energy-dependent covariance matrices as the accepted manner of quantifying the uncertainty data. The trend for the dosimetry community to require high fidelity treatment of uncertainty estimates has continued to the current time where requirements on nuclear data are codified in standards such as ASTM E 1018. This paper surveys the current state of the dosimetry cross sections and investigates the quality of the current dosimetry cross section evaluations by examining calculated-to-experimental ratios in neutron benchmark fields. In recent years more nuclear-related technical areas are placing an emphasis on uncertainty quantification. With the availability of model-based cross sections and covariance matrices produced by nuclear data codes, some nuclear-related communities are considering the role these covariance matrices should play. While funding within the dosimetry community for cross section evaluations has been very meager, other areas, such as the solar-related astrophysics community and the US Nuclear Criticality Safety Program, have been supporting research in the area of neutron cross sections. The Cross Section Evaluation Working Group (CSEWG) is responsible for the creation and maintenance of the ENDF/B library which has been the mainstay for the reactor dosimetry community. Given the new trends in cross section evaluations, this paper explores the path forward for the US nuclear reactor dosimetry community and its use of the ENDF/B cross-sections. The major concern is maintenance of the sufficiency and accuracy of the uncertainty estimate when used for dosimetry applications. The two major areas of deficiency in the proposed ENDF/B approach are: 1) the use of unrelated covariance matrices in ENDF/B evaluations and 2) the lack of 'due consideration' of experimental data

  4. Parenting, identity development, internalizing symptoms, and alcohol use: a cross-sectional study in a group of Italian adolescents

    PubMed Central

    Pellerone, Monica; Tolini, Giacomo; Polopoli, Caterina

    2016-01-01

    Background Literature has demonstrated the adaptive function of identity development and parenting toward manifestation of problem behaviors in adolescence. These dimensions act on both internalizing and externalizing symptoms. Methods The objective is to investigate the relationship between identity status, parenting, and adolescent problems, which may manifest through internalized (phobias, obsessions, depression, eating disorders, entropy) and externalized modes (alcohol use and school discomfort). The research involved 198 Italian students (104 males and 94 females) in the 4th year (mean =16.94 years, standard deviation =0.35) and 5th year (mean =17.94 years, standard deviation =0.43) of senior secondary schools, who live in Caltanissetta, a town located in Sicily, Italy. The research lasted for 1 school year. The general group consisted of 225 students with a mortality rate of 12%. They completed an anamnestic questionnaire to provide 1) basic information, 2) alcohol consumption attitude in the past 30 days, and 3) their beliefs about alcohol; the “Ego Identity Process Questionnaire” to investigate identity development; the “Parental Bonding Instrument” to measure the perception of parenting during childhood; and the “Constraints of Mind” to value the presence of internalizing symptoms. Results Data show that identity status influences alcohol consumption. Low-profile identity and excessive maternal control affect the relational dependence and the tendency to perfectionism in adolescents. Among the predictors of alcohol use, there are socioeconomic status, parental control, and the presence of internalizing symptoms. Conclusion Family is the favored context of learning beliefs, patterns, and values that affect the broader regulatory social environment, and for this reason, it is considered the privileged context on which to intervene to reduce the adolescents’ behavior problems. This deviance could be an external manifestation of the difficulty

  5. Poor reproductive health among a group of socially damaged Middle Eastern women: a cross-sectional study

    PubMed Central

    Mohammadi, Gohar; Amiraliakbari, Sedigheh; Ramezankhani, Ali; Majd, Hamid Alavi

    2011-01-01

    . Contraception was completely ignored in 44.6% of participants. Among eligible women, 53.3% never participated in cervical cancer screening examination. Mean sexual performance scale score was 21.9 (5.5) and 75 (83.3%) participants scored less than 28. Conclusion A high prevalence of poor reproductive health was documented among a group of Middle Eastern socially damaged women. PMID:22140328

  6. Drell-Yan Cross Sections: Data from DOE laboratory experiments as compiled in data reviews by the Durham High Energy Physics Database Group

    DOE Data Explorer

    Stirling, W. J.; Whalley, M. R.

    A compilation of data on Drell-Yan cross sections above a lepton-pair mass of 4 GeV/c2 is presented. The relevant experiments at Fermilab and CERN are included dating from approximately 1977 to the present day, covering p, p and pi +or- beams on a variety of nuclear and hydrogen targets, with centre-of-mass energies from 8.6 GeV to 630 GeV. The type of data presented include d sigma /dm, d2 sigma /dm dx and d2 sigma /dm dy distributions as well as other variations of these, and also transverse momentum distributions. The data are compared with a standard theoretical model, and a phenomenological 'K-factor' for each set is calculated. (Taken from the abstract of A Compilation of Drell-Yan Cross sections, W.J. Stirling and M.R. Whalley, Journal of Physics G (Nuclear and Particle Physics), Volume 19, Data Review, 1993.) The Durham High Energy Physics (HEP) Database Group makes these data, extracted from papers and data reviews, available in one place in an easy-to-access format. These data are also included in the Durham HEP Reaction Data Database which can be searched at http://hepdata.cedar.ac.uk/reaction

  7. Hadronic Total Cross Sections (R) in E+E- Interactions: Data from DOE laboratory experiments as compiled in data reviews by the Durham High Energy Physics Database Group

    DOE Data Explorer

    Whalley, M. R.

    A comprehensive compilation of experimental data on total hadronic cross sections, and R ratios, in e+e- interactions is presented. Published data from the Novosibirsk, Orsay, Frascati, SLAC, CORNELL, DESY, KEK and CERN e+e- colliders on both exclusive and inclusive final particle states are included from threshold energies to the highest LEP energies. The data are presented in tabular form supplemented by compilation plots of different exclusive final particle states and of different energy regions. (Taken from abstract of paper, A Compilation of Data on Hadronic Total Cross Sections in E+E- Interactions, M.R. Whalley, Journal of Physics G (Nuclear and Particle Physics), Volume 29, Number 12A, 2003). The Durham High Energy Physics (HEP) Database Group makes these data, extracted from papers and data reviews, available in one place in an easy-to-access format. The data are also included in the Durham HEP Reaction Data Database, which can be searched at http://hepdata.cedar.ac.uk/reaction

  8. Improved cross section calculations for astrophysical applications

    NASA Technical Reports Server (NTRS)

    Silberberg, R.; Tsao, C. H.; Letaw, J. R.

    1985-01-01

    Modifications are proposed for the semiempirical equations and parameters of Silberberg and Tsao (1973) for partial cross section calculations of proton-nucleus reactions in cosmic rays. These modifications include: adjustment of general parameters; modification of energy dependence; effects of nuclear alpha-particle structure, deuteron emission, and even-charged products; peripheral reactions; fission reactions; averaging cross sections near boundaries of different parameters; elimination of certain special cases; and treatment of the Pt to Pb group that cannot yet be generalized to Z(t) less than 76.

  9. Provision of group psychoeducation for relatives of persons in inpatient depression treatment – a cross-sectional survey of acute care hospitals in Germany

    PubMed Central

    2014-01-01

    Background Depressive disorders are often recurrent and place a high burden on patients and their relatives. Psychoeducational groups for relatives may reduce relatives’ burden, help prevent relapses in patients, and are recommended by the German “National Disease Management Guideline Unipolar Depression”. Since there is limited knowledge on the provision of psychoeducational groups for relatives of persons in inpatient depression treatment, we conducted a survey among acute care hospitals in Germany. Methods We conducted a two-step cross-sectional survey. Step I consisted of a questionnaire asking the heads of all psychiatric/psychosomatic acute care hospitals in Germany (N = 512) whether psychoeducational groups for relatives were provided within depression treatment, and if not, the reasons for not implementing them. In group offering hospitals the person responsible for conducting psychoeducational groups received a detailed questionnaire on intervention characteristics (step II). We performed descriptive data analysis. Results The response rate was 50.2% (N = 257) in step I and 58.4% in step II (N = 45). 35.4% of the responding hospitals offered psychoeducational groups for relatives of patients with depressive disorders. According to the estimates of the respondents, relatives of about one in five patients took part in psychoeducational groups in 2011. Groups were mostly provided by two moderators (62.2%) as continuous groups (77.8%), without patients’ participation (77.8%), with up to ten participants (65.9%), consisting of four or fewer sessions (51.5%) which lasted between one and one and a half hours each (77.8%). The moderators in charge were mostly psychologists (43.9%) or physicians (26.8%). Approximately one third used published manuals. Reasons for not conducting such psychoeducational groups were lack of manpower (60.1%), time (44.9%) and financial constraints (24.1%). 25.3% mentioned adequate concepts of intervention as a

  10. Recommended Dosimetry Cross Section Compendium.

    Energy Science and Technology Software Center (ESTSC)

    1994-07-11

    Version 00 The data is recommended for spectrum determination applications and for the prediction of neutron activation of typical radiation sensor materials. The library has been tested for consistency of the cross sections in a wide variety of neutron environments. The results and cautions from this testing have been documented. The data has been interfaced with radiation transport codes, such as TWODANT-SYS (CCC-547) and MCNP (CCC-200), in order to compare calculated and measured activities formore » benchmark reactor experiments.« less

  11. (Fast neutron cross section measurements)

    SciTech Connect

    Not Available

    1991-01-01

    In the 14 MeV Neutron Laboratory, we have continued the development of a facility that is now the only one of its kind in operation in the United States. We have refined the klystron bunching system described in last year's report to the point that 1.2 nanosecond pulses have been directly measured. We have tested the pulse shape discrimination capability of our primary NE 213 neutron detector. We have converted the RF sweeper section of the beamline to a frequency of 1 MHz to replace the function of the high voltage pulser described in last year's report which proved to be difficult to maintain and unreliable in its operation. We have also overcome several other significant experimental difficulties, including a major problem with a vacuum leak in the main accelerator column. We have completed additional testing to prove the remainder of the generation and measurement systems, but overcoming some of these experimental difficulties has delayed the start of actual data taking. We are now in a position to begin our first series of ring geometry elastic scattering measurements, and these will be underway before the end of the current contract year. As part of our longer term planning, we are continuing the conceptual analysis of several schemes to improve the intensity of our current pulsed beam. These include the provision of a duoplasmatron ion source and/or the provision of preacceleration bunching. Additional details are given later in this report. A series of measurements were carried out at the Tandem Dynamatron Facility involving the irradiation of a series of yttrium foils and the determination of activation cross sections using absolute counting techniques. The experimental work has been completed, and final analysis of the cross section data will be completed within several months.

  12. Cross-Sectional and Longitudinal Comparisons of the Predominant Fecal Microbiota Compositions of a Group of Pediatric Patients with Cystic Fibrosis and Their Healthy Siblings▿†

    PubMed Central

    Duytschaever, Gwen; Huys, Geert; Bekaert, Maarten; Boulanger, Linda; De Boeck, Kris; Vandamme, Peter

    2011-01-01

    Although only poorly documented, it can be assumed that intensive antibiotic treatments of chronic lung infections in patients with cystic fibrosis (CF) also affect the diversity and metabolic functioning of the gastrointestinal microbiota and potentially lead to a state of dysbiosis. A better knowledge of the differences in gut microbiota composition and stability between patients with CF and healthy subjects could lead to optimization of current antibiotic therapies and/or development of add-on therapies. Using conventional culturing and population fingerprinting by denaturing gradient gel electrophoresis (DGGE) of 16S rRNA amplicons, we compared the predominant fecal microbiota of 21 patients with CF and 24 healthy siblings in a cross-sectional study. General medium counts, as well as counts on media specific for lactic acid bacteria, clostridia, Bifidobacterium spp., Veillonella spp., and Bacteroides-Prevotella spp., were consistently higher in sibling samples than in CF samples, whereas the reverse was found for enterobacterial counts. DGGE fingerprinting uncovered large intersubject variations in both study groups. On the other hand, the cross-sectional data indicated that the predominant fecal microbiota of patients and siblings had comparable species richness. In addition, a longitudinal study was performed on 7 or 8 consecutive samples collected over a 2-year period from two patients and their respective siblings. For these samples, DGGE profiling indicated an overall trend toward lower temporal stability and lower species richness in the predominant fecal CF microbiota. The observed compositional and dynamic perturbations provide the first evidence of a general dysbiosis in children with CF compared to their siblings. PMID:21926193

  13. Electron-Impact Ionization Cross Section Database

    National Institute of Standards and Technology Data Gateway

    SRD 107 Electron-Impact Ionization Cross Section Database (Web, free access)   This is a database primarily of total ionization cross sections of molecules by electron impact. The database also includes cross sections for a small number of atoms and energy distributions of ejected electrons for H, He, and H2. The cross sections were calculated using the Binary-Encounter-Bethe (BEB) model, which combines the Mott cross section with the high-incident energy behavior of the Bethe cross section. Selected experimental data are included.

  14. Production and testing of the VITAMIN-B6 fine-group and the BUGLE-93 broad-group neutron/photon cross-section libraries derived from ENDF/B-VI nuclear data

    SciTech Connect

    Ingersoll, D.T.; White, J.E.; Wright, R.Q.; Hunter, H.T.; Slater, C.O.; Greene, N.M.; MacFarlane, R.E.

    1993-11-01

    A new multigroup cross-section library based on ENDF/B-VI data has been produced and tested for light water reactor shielding and reactor pressure vessel dosimetry applications. The broad-group library is designated BUGLE-93. The processing methodology is consistent with ANSI/ANS 6.1.2, since the ENDF data were first processed into a fine-group, ``pseudo problem-independent`` format and then collapsed into the final broad-group format. The fine-group library is designated VITAMIN-B6. An extensive integral data testing effort was also performed. In general, results using the new data show significant improvements relative to earlier ENDF data.

  15. Production and Testing of the VITAMIN-B6 Fine Group and the BUGLE-93 Broad-Group Neutron/Photon Cross-Section Libraries Derived from ENDF/B-VI Nuclear Data

    SciTech Connect

    White, J.E.

    2001-04-19

    A revised multigroup cross-section library based on Release 3 of ENDF/B-VI data has been produced and tested for light-water-reactor shielding and reactor pressure vessel dosimetry applications. This new broad-group library, which is designated BUGLE-96, represents an improvement over the BUGLE-93 data library released in February 1994 and replaces the data package for BUGLE-93 in the Radiation Safety Information Computational Center (formerly RSIC). The processing methodology is the same as that used for producing BUGLE-93 and is consistent with ANSI/ANS 6.1.2. The ENDF data were first processed into a fine-group, pseudo-problem-independent format and then collapsed into the final broad-group format. The fine-group library, which is designated VITAMIN-B6, contains 120 nuclides. The BUGLE-96 47-neutron-group/20-gamma-ray-group library contains the same 120 nuclides processed as infinitely dilute and collapsed using a weighting spectrum typical of a concrete shield. Additionally, nuclides processed with resonance self-shielding and weighted using spectra specific to BWR and PWR material compositions and reactor models are available. As an added feature of BUGLE-96, cross-section sets having upscatter data for four thermal neutron groups are included. The upscattering data should improve the application of BUGLE-96 to the calculation of more accurate thermal fluences, although more computer time will be required. Several new dosimetry response functions and kerma factors for all 120 nuclides are also included in the library. The incorporation of feedback from users has resulted in a data library that addresses a wider spectrum of user needs.

  16. Photoproduction total cross section and shower development

    NASA Astrophysics Data System (ADS)

    Cornet, F.; García Canal, C. A.; Grau, A.; Pancheri, G.; Sciutto, S. J.

    2015-12-01

    The total photoproduction cross section at ultrahigh energies is obtained using a model based on QCD minijets and soft-gluon resummation and the ansatz that infrared gluons limit the rise of total cross sections. This cross section is introduced into the Monte Carlo system AIRES to simulate extended air showers initiated by cosmic ray photons. The impact of the new photoproduction cross section on common shower observables, especially those related to muon production, is compared with previous results.

  17. Testing WIMS-D4M cross sections and the ANL ENDF/B-V 69 group library. Results from global diffusion and Monte Carlo calculations compared with measurements in the Romanian 14-MW TRIGA reactor

    SciTech Connect

    Bretscher, M.M.

    1993-12-31

    The WIMS-D4 code has been modified (WIMS-D4M) to produce microscopic isotopic cross sections in ISOTXS format for use in diffusion and transport calculations. Beginning with 69-group libraries based on ENDF/B-V data, numerous cell calculations have been made to prepare a set of broad group cross sections for use in diffusion calculations. Global calculations have been made for two control rod states of the Romanian steady state TRIGA reactor with 29 fresh HEU fuel clusters. Detailed Monte Carlo calculations also have been performed for the same reactor configurations using data based on ENDF/B-V. Results from these global calculations are compared with each other and with the measured excess reactivities. Although region-averaged macroscopic principal cross sections obtained from WIMS-D4M are in good agreement with the corresponding Monte Carlo values, problems exist with the high energy (E > 10 keV) microscopic hydrogen transport cross sections.

  18. Cross Sections: No. 1 Hold section at Fr 24 Looking ...

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

    Cross Sections: No. 1 Hold section at Fr 24 Looking Fwd, No 1 Hold Section at Fr 28 Looking Aft, No 2 Hold Section at Fr 48 Looking Aft, No 3 Hold Section at Fr 70 Looking Aft, No 4 Hold Section at Fr 90 Looking Aft - General John Pope, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  19. Electron Photon Interaction Cross Sections

    Energy Science and Technology Software Center (ESTSC)

    2014-11-01

    Version 00 The Electron Photon Interaction Cross Sections, EPICS, provides the atomic data needed to perform coupled Electron-Photon transport calculations, to produce accurate macroscopic results, such as energy deposit and dose. Atomic data is provided for elements, Z = 1 to 100, over the energy range 10 eV to 100 GeV; note that nuclear data, such as photo-nuclear, and data for compounds, are not included. All data is in a simple computer independent text formatmore » that is standard and presented to a high precision that can be easily read by computer codes written in any computer language, e.g., C, C++, and FORTRAN. EPICS includes four separate data bases that are designed to be used in combination, these include, • The Evaluated Electron Data Library (EEDL), to describe the interaction of electrons with matter. • The Evaluated Photon Data Library (EPDL), to describe the interaction of photons with matter. • The Evaluated Atomic Data Library (EADL), to describe the emission of electrons and photons back to neutrality following an ionizing event, caused by either electron or photon interactions. • The Evaluated Excitation Data Library (EXDL), to describe the excitation of atoms due to photon interaction. All of these are available in the Extended ENDL format (ENDLX) in which the evaluations were originally performed. The first three are also available in the ENDF format; as yet ENDF does not include formats to handle excitation data (EXDL).« less

  20. Electron Photon Interaction Cross Sections

    SciTech Connect

    Cullen, D. E.

    2014-11-01

    Version 00 The Electron Photon Interaction Cross Sections, EPICS, provides the atomic data needed to perform coupled Electron-Photon transport calculations, to produce accurate macroscopic results, such as energy deposit and dose. Atomic data is provided for elements, Z = 1 to 100, over the energy range 10 eV to 100 GeV; note that nuclear data, such as photo-nuclear, and data for compounds, are not included. All data is in a simple computer independent text format that is standard and presented to a high precision that can be easily read by computer codes written in any computer language, e.g., C, C++, and FORTRAN. EPICS includes four separate data bases that are designed to be used in combination, these include, • The Evaluated Electron Data Library (EEDL), to describe the interaction of electrons with matter. • The Evaluated Photon Data Library (EPDL), to describe the interaction of photons with matter. • The Evaluated Atomic Data Library (EADL), to describe the emission of electrons and photons back to neutrality following an ionizing event, caused by either electron or photon interactions. • The Evaluated Excitation Data Library (EXDL), to describe the excitation of atoms due to photon interaction. All of these are available in the Extended ENDL format (ENDLX) in which the evaluations were originally performed. The first three are also available in the ENDF format; as yet ENDF does not include formats to handle excitation data (EXDL).

  1. [Fast neutron cross section measurements

    SciTech Connect

    Knoll, G.F.

    1992-10-26

    From its inception, the Nuclear Data Project at the University of Michigan has concentrated on two major objectives: (1) to carry out carefully controlled nuclear measurements of the highest possible reliability in support of the national nuclear data program, and (2) to provide an educational opportunity for students with interests in experimental nuclear science. The project has undergone a successful transition from a primary dependence on our photoneutron laboratory to one in which our current research is entirely based on a unique pulsed 14 MeV fast neutron facility. The new experimental facility is unique in its ability to provide nanosecond bursts of 14 MeV neutrons under conditions that are clean'' and as scatter-free as possible, and is the only one of its type currently in operation in the United States. It has been designed and put into operation primarily by graduate students, and has met or exceeded all of its important initial performance goals. We have reached the point of its routine operation, and most of the data are now in hand that will serve as the basis for the first two doctoral dissertations to be written by participating graduate students. Our initial results on double differential neutron cross sections will be presented at the May 1993 Fusion Reactor Technology Workshop. We are pleased to report that, after investing several years in equipment assembly and optimization, the project has now entered its data production'' phase.

  2. Relationship between Body mass index (BMI) and body fat percentage, estimated by bioelectrical impedance, in a group of Sri Lankan adults: a cross sectional study

    PubMed Central

    2013-01-01

    Background Body Mass Index (BMI) is used as a useful population-level measure of overweight and obesity. It is used as the same for both sexes and for all ages of adults. The relationship between BMI and body fat percentage (BF %) has been studied in various ethnic groups to estimate the capacity of BMI to predict adiposity. We aimed to study the BMI–BF% relationship, in a group of South Asian adults who have a different body composition compared to presently studied ethnic groups. We examined the influence of age, gender in this relationship and assessed its’ linearity or curvilinearity. Methods A cross sectional study was conducted, where adults of 18–83 years were grouped into young (18–39 years) middle aged (40–59 years) and elderly (>60 years). BF% was estimated from bioelectrical impedance analysis. Pearsons’ correlation coefficient(r) was calculated to see the relationship between BMI-BF% in the different age groups. Multiple regression analysis was performed to determine the effect of age and gender in the relationship and polynomial regression was carried out to see its’ linearity. The relationships between age-BMI, age-BF % were separately assessed. Results Out of 1114 participants, 49.1% were males. The study sample represented a wide range of BMI values (14.8-41.1 kg/m2,Mean 23.8 ± 4.2 kg/m2). A significant positive correlation was observed between BMI-BF%, in males (r =0.75, p < 0.01; SEE = 4.17) and in females (r = 0.82, p < 0.01; SEE = 3.54) of all ages. Effect of age and gender in the BMI-BF% relationship was significant (p < 0.001); with more effect from gender. Regression line found to be curvilinear in nature at higher BMI values where females (p < 0.000) having a better fit of the curve compared to males (p < 0.05). In both genders, with increase of age, BMI seemed to increase in curvilinear fashion, whereas BF% increased in a linear fashion. Conclusions BMI strongly correlate with BF

  3. Recent fission cross section standards measurements

    SciTech Connect

    Wasson, O.A.

    1985-01-01

    The /sup 235/U(n,f) reaction is the standard by which most neutron induced fission cross sections are determined. Most of these cross sections are derived from relatively easy ratio measurements to /sup 235/U. However, the more difficult /sup 235/U(n,f) cross section measurements require the use of advanced neutron detectors for the determination of the incident neutron fluence. Examples of recent standard cross section measurements are discussed, various neutron detectors are described, and the status of the /sup 235/U(n,f) cross section standard is assessed. 23 refs., 8 figs., 4 tabs.

  4. SNL RML recommended dosimetry cross section compendium

    SciTech Connect

    Griffin, P.J.; Kelly, J.G.; Luera, T.F.; VanDenburg, J.

    1993-11-01

    A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty and variation in cross sections presented by state-of-the-art evaluations.

  5. Physical activity and cardiovascular risk factors among rural and urban groups and rural-to-urban migrants in Peru: a cross-sectional study

    PubMed Central

    Creber, Ruth M. Masterson; Smeeth, Liam; Gilman, Robert H.; Miranda, J. Jaime

    2010-01-01

    Objectives To compare physical activity and sedentary behavior patterns of rural-to-urban migrants in Peru versus lifetime rural and urban residents and to determine any associations between low physical activity and four cardiovascular risk factors: obesity (body mass index ≥ 30 kg/m2), systolic and diastolic blood pressure, hypertension, and metabolic syndrome. Methods The PERU MIGRANT (PEru’s Rural to Urban MIGRANTs) cross-sectional study was designed to measure physical activity among rural, urban, and rural-to-urban migrants with the International Physical Activity Questionnaire (IPAQ). Results The World Health Organization (WHO) age-standardized prevalence of low physical activity was 2.2% in lifetime rural residents, 32.2% in rural-to-urban migrants, and 39.2% in lifetime urban residents. The adjusted odds ratios for low physical activity were 21.43 and 32.98 for migrant and urban groups respectively compared to the rural group. The adjusted odds ratio for being obese was 1.94 for those with low physical activity. There was no evidence of an association between low physical activity and blood pressure levels, hypertension, or metabolic syndrome. Conclusions People living in a rural area had much higher levels of physical activity and lower risk of being overweight and obese compared to those living in an urban area of Lima. Study participants from the same rural area who had migrated to Lima had levels of physical inactivity and obesity similar to those who had always lived in Lima. Interventions aimed at maintaining higher levels of physical activity among rural-to-urban migrants may help reduce the epidemic of obesity in urban areas. PMID:20857014

  6. Calculation of improved spallation cross sections

    NASA Technical Reports Server (NTRS)

    Tsao, C. H.; Silberberg, R.; Letaw, J. R.

    1985-01-01

    Several research groups have recently carried out highly precise measurements (to about 10 percent) of high-energy nuclear spallation cross sections. These measurements, above 5 GeV, cover a broad range of elements: V, Fe, Cu, Ag, Ta and Au. Even the small cross sections far off the peak of the isotopic distribution curves have been measured. The semiempirical calculations are compared with the measured values. Preliminary comparisons indicate that the parameters of our spallation relations (Silberberg and Tsao, 1973) for atomic numbers 20 to 83 need modifications, e.g. a reduced slope of the mass yield distribution, broader isotopic distributions, and a shift of the isotopic distribution toward the neutron-deficient side. The required modifications are negligible near Fe and Cu, but increase with increasing target mass.

  7. Group A β-hemolytic Streptococcal Infection in Children and the Resultant Neuro-psychiatric Disorder; a Cross Sectional Study; Tehran, Iran

    PubMed Central

    Ebrahimi Taj, Farideh; Noorbakhsh, Samileh; Ghavidel Darestani, Sahar; Shirazi, Elham; Javadinia, Shima

    2015-01-01

    Introduction: Group A Beta-Hemolytic Streptococcus (GABHS) can induce PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection). GABHS is the most important and common bacterial cause of acute pharyngitis in Iranian children. We studied the role of GABHS (anti-streptococcal antibodies) in suspected cases of PANDAS in a cross sectional studies. Methods: Across sectional study was done in 2 pediatric psychiatric/and neurologic clinics in Tehran (Rasul Akram and Aliasghar Hospital) during 2008–2010. We studied serum anti-streptococcal antibodies (anti streptolysin O, anti Deoxyribonuclease B, and anti-streptokinase (ABcam-ELISA, USA) in 76 cases with psychiatric manifestation (OCD, ADHD) in compare with 39 healthy controls. These antibodies were studied in 53 cases with movement disorders (Tic/Tourette syndrome) in compare with 76 healthy controls. Sensitivity, specificity and positive predictive value of tests were calculated. Results: In movement disorders ASOT, Anti-DNase and Anti streptokinase was significantly higher than controls (P<0.0001, P=0.000, P<0.00001) ASOT (cut off level> 200 IU/ml) had 75% sensitivity; 84% specificity and 80% PPV; Anti-streptokinase (cut off level > 332 IU/ml) had 34% sensitivity; 85% specificity, and 72% PPV; Anti-DNase (cut off level > 140 IU/ml) had 70% sensitivity; 99% specificity and PPV 90% for differentiating the group. ASOT, Anti-DNase and Anti streptokinase titer was significantly higher than controls (P<0.0001, P=0.000, P<0.0001). ASOT had 90% sensitivity; 82% specificity, PPV 92%; Anti streptokinase: 82% sensitivity; 82% specificity, PPV 95%; Anti DNase: 92% sensitivity; 82% specificity, PPV 92% for differentiation the cases from normal controls. Discussion: These findings support that a post infectious immune mechanism to GABHS may play a role in the pathogenesis of PANDAS in our children. A combination of throat culture, rapid antigen detection test, and serologic testing for GABHS

  8. Cross Sections: No 6 Hold Section at Fr 178 Looking ...

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

    Cross Sections: No 6 Hold Section at Fr 178 Looking Fwd, No 7 Hold Section at No 154 Looking Fwd, No 7 Hold Section at Fr 195 Looking Fwd Showing Trans 194, No 7 Hold Section at Fr 198 Looking Fwd - General John Pope, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  9. Patients with unexplained physical symptoms have poorer quality of life and higher costs than other patient groups: a cross-sectional study on burden

    PubMed Central

    2013-01-01

    Background To determine whether healthcare resources are allocated fairly, it is helpful to have information on the quality of life (QoL) of patients with Unexplained Physical Symptoms (UPS) and on the costs associated with them, and on how these relate to corresponding data in other patient groups. As studies to date have been limited to specific patient populations with UPS, the objective of this study was to assess QoL and costs in a general sample of patients with UPS using generic measures. Methods In a cross-sectional study, 162 patients with UPS reported on their QoL, use of healthcare resources and lost productivity in paid and unpaid work. To assess QoL, the generic SF-36 questionnaire was used, from which multidimensional quality-of-life scores and a one-dimensional score (utility) using the SF-6D scorings algorithm were derived. To assess costs, the TiC-P questionnaire was used. Results Patients with UPS reported a poor QoL. Their QoL was mostly decreased by limitations in functioning due to physical health, and the least by limitations in functioning due to emotional problems. The median of utilities was 0.57, and the mean was 0.58 (SD = .09). The cost for the use of healthcare services was estimated to be €3,123 (SD = €2,952) per patient per year. This cost was enlarged by work-related costs: absence from work (absenteeism), lower on-the-job productivity (presenteeism), and paid substitution of domestic tasks. The resulting mean total cost was estimated to be €6,815 per patient per year. Conclusions These findings suggest that patients with UPS have a high burden of disease and use a considerable amount of healthcare resources. In comparison with other patient groups, the QoL values of patients with UPS were among the poorest and their costs were among the highest of all patient groups. The burden for both patients and society helps to justify the allocation of sufficient resources to effective treatment for patients with UPS. Trial

  10. 66 Neutron, 22 Gamma-Ray Group Cross Sections for Radiation Transport for Neutron Energies Up to 400 MeV.

    Energy Science and Technology Software Center (ESTSC)

    1995-12-12

    Version 00 For a variety of applications (accelerator shielding, the use of neutrons in radiotherapy, radiation damage studies, etc.) It is necessary to carry out transport calculations involving medium-energy neutrons. HILO86R multigroup cross sections are in the form needed for the CCC-254/ANISN-ORNL and CCC-543/TORT-DORT discrete ordinates codes and in the CCC-474/MORSE-CGA Monte Carlo code.

  11. A Multi-Country Cross-Sectional Study of Vaginal Carriage of Group B Streptococci (GBS) and Escherichia coli in Resource-Poor Settings: Prevalences and Risk Factors

    PubMed Central

    Cools, Piet; Jespers, Vicky; Hardy, Liselotte; Crucitti, Tania; Delany-Moretlwe, Sinead; Mwaura, Mary; Ndayisaba, Gilles F.; van de Wijgert, Janneke H. H. M.; Vaneechoutte, Mario

    2016-01-01

    Background One million neonates die each year in low- and middle-income countries because of neonatal sepsis; group B Streptococcus (GBS) and Escherichia coli are the leading causes. In sub-Saharan Africa, epidemiological data on vaginal GBS and E. coli carriage, a prerequisite for GBS and E. coli neonatal sepsis, respectively, are scarce but necessary to design and implement prevention strategies. Therefore, we assessed vaginal GBS and E. coli carriage rates and risk factors and the GBS serotype distribution in three sub-Saharan countries. Methods A total of 430 women from Kenya, Rwanda and South Africa were studied cross-sectionally. Vaginal carriage of GBS and E. coli, and GBS serotype were assessed using molecular techniques. Risk factors for carriage were identified using multivariable logistic regression analysis. Results Vaginal carriage rates in reference groups from Kenya and South Africa were 20.2% (95% CI, 13.7–28.7%) and 23.1% (95% CI, 16.2–31.9%), respectively for GBS; and 25.0% (95% CI, 17.8–33.9%) and 27.1% (95% CI, 19.6–36.2%), respectively for E. coli. GBS serotypes Ia (36.8%), V (26.3%) and III (14.0%) were most prevalent. Factors independently associated with GBS and E. coli carriage were Candida albicans, an intermediate vaginal microbiome, bacterial vaginosis, recent vaginal intercourse, vaginal washing, cervical ectopy and working as a sex worker. GBS and E. coli carriage were positively associated. Conclusions Reduced vaginal GBS carriage rates might be accomplished by advocating behavioral changes such as abstinence from sexual intercourse and by avoidance of vaginal washing during late pregnancy. It might be advisable to explore the inclusion of vaginal carriage of C. albicans, GBS, E. coli and of the presence of cervical ectopy in a risk- and/or screening-based administration of antibiotic prophylaxis. Current phase II GBS vaccines (a trivalent vaccine targeting serotypes Ia, Ib, and III, and a conjugate vaccine targeting serotype

  12. Vertically stabilized elongated cross-section tokamak

    DOEpatents

    Sheffield, George V.

    1977-01-01

    This invention provides a vertically stabilized, non-circular (minor) cross-section, toroidal plasma column characterized by an external separatrix. To this end, a specific poloidal coil means is added outside a toroidal plasma column containing an endless plasma current in a tokamak to produce a rectangular cross-section plasma column along the equilibrium axis of the plasma column. By elongating the spacing between the poloidal coil means the plasma cross-section is vertically elongated, while maintaining vertical stability, efficiently to increase the poloidal flux in linear proportion to the plasma cross-section height to achieve a much greater plasma volume than could be achieved with the heretofore known round cross-section plasma columns. Also, vertical stability is enhanced over an elliptical cross-section plasma column, and poloidal magnetic divertors are achieved.

  13. Cross Sections for Electron Collisions with Methane

    SciTech Connect

    Song, Mi-Young Yoon, Jung-Sik; Cho, Hyuck; Itikawa, Yukikazu; Karwasz, Grzegorz P.; Kokoouline, Viatcheslav; Nakamura, Yoshiharu; Tennyson, Jonathan

    2015-06-15

    Cross section data are compiled from the literature for electron collisions with methane (CH{sub 4}) molecules. Cross sections are collected and reviewed for total scattering, elastic scattering, momentum transfer, excitations of rotational and vibrational states, dissociation, ionization, and dissociative attachment. The data derived from swarm experiments are also considered. For each of these processes, the recommended values of the cross sections are presented. The literature has been surveyed through early 2014.

  14. Theoretical antideuteron-nucleus absorptive cross sections

    NASA Technical Reports Server (NTRS)

    Buck, W. W.; Norbury, J. W.; Townsend, L. W.; Wilson, J. W.

    1993-01-01

    Antideuteron-nucleus absorptive cross sections for intermediate to high energies are calculated using an ion-ion optical model. Good agreement with experiment (within 15 percent) is obtained in this same model for (bar p)-nucleus cross sections at laboratory energies up to 15 GeV. We describe a technique for estimating antinucleus-nucleus cross sections from NN data and suggest that further cosmic ray studies to search for antideuterons and other antinuclei be undertaken.

  15. Annular-Cross-Section CFE Chamber

    NASA Technical Reports Server (NTRS)

    Sharnez, Rizwan; Sammons, David W.

    1994-01-01

    Proposed continuous-flow-electrophoresis (CFE) chamber of annular cross section offers advantages over conventional CFE chamber, and wedge-cross-section chamber described in "Increasing Sensitivity in Continuous-Flow Electrophoresis" (MFS-26176). In comparison with wedge-shaped chamber, chamber of annular cross section virtually eliminates such wall effects as electro-osmosis and transverse gradients of velocity. Sensitivity enhanced by incorporating gradient maker and radial (collateral) flow.

  16. Absolute partial photoionization cross sections of ozone.

    SciTech Connect

    Berkowitz, J.; Chemistry

    2008-04-01

    Despite the current concerns about ozone, absolute partial photoionization cross sections for this molecule in the vacuum ultraviolet (valence) region have been unavailable. By eclectic re-evaluation of old/new data and plausible assumptions, such cross sections have been assembled to fill this void.

  17. Neutrino flux predictions for cross section measurements

    SciTech Connect

    Hartz, Mark

    2015-05-15

    Experiments that measure neutrino interaction cross sections using accelerator neutrino sources require a prediction of the neutrino flux to extract the interaction cross section from the measured neutrino interaction rate. This article summarizes methods of estimating the neutrino flux using in-situ and ex-situ measurements. The application of these methods by current and recent experiments is discussed.

  18. Use and Uptake of eHealth in General Practice: A Cross-Sectional Survey and Focus Group Study Among Health Care Users and General Practitioners

    PubMed Central

    Krijgsman, Johan W; Brabers, Anne E; Jong, Judith D De; Friele, Roland D

    2016-01-01

    Background Policy makers promote the use of eHealth to widen access to health care services and to improve the quality and safety of care. Nevertheless, the enthusiasm among policy makers for eHealth does not match its uptake and use. eHealth is defined in this study as “health services delivered or enhanced through the Internet and related information and communication technologies.” Objective The objective of this study was to investigate (1) the current use of eHealth in the Netherlands by general practitioners (GPs) and health care users, (2) the future plans of GPs to provide eHealth and the willingness of health care users to use eHealth services, and (3) the perceived positive effects and barriers from the perspective of GPs and health care users. Methods A cross-sectional survey of a sample of Dutch GPs and members of the Dutch Health Care Consumer Panel was conducted in April 2014. A pre-structured questionnaire was completed by 171 GPs (12% response) and by 754 health care users (50% response). In addition, two focus groups were conducted in June 2014: one group with GPs (8 participants) and one with health care users (10 participants). Results Three-quarters of Dutch GPs that responded to the questionnaire (67.3%, 115/171) offered patients the possibility of requesting a prescription via the Internet, and half of them offered patients the possibility of asking a question via the Internet (49.1%, 84/171). In general, they did intend to provide future eHealth services. Nonetheless, many of the GPs perceived barriers, especially concerning its innovation (eg, insufficient reliable, secure systems) and the sociopolitical context (eg, lack of financial compensation for the time spent on implementation). By contrast, health care users were generally not aware of existing eHealth services offered by their GPs. Nevertheless, half of them were willing to use eHealth services when offered by their GP. In general, health care users have positive attitudes

  19. Cross Section Evaluations for Arsenic Isotopes

    SciTech Connect

    Pruet, J; McNabb, D P; Ormand, W E

    2005-03-10

    The authors present an evaluation of cross sections describing reactions with neutrons incident on the arsenic isotopes with mass numbers 75 and 74. Particular attention is paid to (n,2n) reactions. The evaluation for {sup 75}As, the only stable As isotope, is guided largely by experimental data. Evaluation for {sup 74}As is made through calculations with the EMPIRE statistical-model reaction code. Cross sections describing the production and destruction of the 26.8 ns isomer in {sup 74}As are explicitly considered. Uncertainties and covariances in some evaluated cross sections are also estimated.

  20. Nucleon-Nucleon Total Cross Section

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2008-01-01

    The total proton-proton and neutron-proton cross sections currently used in the transport code HZETRN show significant disagreement with experiment in the GeV and EeV energy ranges. The GeV range is near the region of maximum cosmic ray intensity. It is therefore important to correct these cross sections, so that predictions of space radiation environments will be accurate. Parameterizations of nucleon-nucleon total cross sections are developed which are accurate over the entire energy range of the cosmic ray spectrum.

  1. Reactivity effects in VVER-1000 of the third unit of the kalinin nuclear power plant at physical start-up. Computations in ShIPR intellectual code system with library of two-group cross sections generated by UNK code

    NASA Astrophysics Data System (ADS)

    Zizin, M. N.; Zimin, V. G.; Zizina, S. N.; Kryakvin, L. V.; Pitilimov, V. A.; Tereshonok, V. A.

    2010-12-01

    The ShIPR intellectual code system for mathematical simulation of nuclear reactors includes a set of computing modules implementing the preparation of macro cross sections on the basis of the two-group library of neutron-physics cross sections obtained for the SKETCH-N nodal code. This library is created by using the UNK code for 3D diffusion computation of first VVER-1000 fuel loadings. Computation of neutron fields in the ShIPR system is performed using the DP3 code in the two-group diffusion approximation in 3D triangular geometry. The efficiency of all groups of control rods for the first fuel loading of the third unit of the Kalinin Nuclear Power Plant is computed. The temperature, barometric, and density effects of reactivity as well as the reactivity coefficient due to the concentration of boric acid in the reactor were computed additionally. Results of computations are compared with the experiment.

  2. Reactivity effects in VVER-1000 of the third unit of the kalinin nuclear power plant at physical start-up. Computations in ShIPR intellectual code system with library of two-group cross sections generated by UNK code

    SciTech Connect

    Zizin, M. N.; Zimin, V. G.; Zizina, S. N. Kryakvin, L. V.; Pitilimov, V. A.; Tereshonok, V. A.

    2010-12-15

    The ShIPR intellectual code system for mathematical simulation of nuclear reactors includes a set of computing modules implementing the preparation of macro cross sections on the basis of the two-group library of neutron-physics cross sections obtained for the SKETCH-N nodal code. This library is created by using the UNK code for 3D diffusion computation of first VVER-1000 fuel loadings. Computation of neutron fields in the ShIPR system is performed using the DP3 code in the two-group diffusion approximation in 3D triangular geometry. The efficiency of all groups of control rods for the first fuel loading of the third unit of the Kalinin Nuclear Power Plant is computed. The temperature, barometric, and density effects of reactivity as well as the reactivity coefficient due to the concentration of boric acid in the reactor were computed additionally. Results of computations are compared with the experiment.

  3. The radar cross section of dielectric disks

    NASA Technical Reports Server (NTRS)

    Levine, D. M.

    1982-01-01

    A solution is presented for the backscatter (nonstatic) radar cross section of dielectric disks of arbitrary shape, thickness and dielectric constant. The result is obtained by employing a Kirchhoff type approximation to obtain the fields inside the disk. The internal fields induce polarization and conduction currents from which the scattered fields and the radar cross section can be computed. The solution for the radar cross section obtained in this manner is shown to agree with known results in the special cases of normal incidence, thin disks and perfect conductivity. The solution can also be written as a product of the reflection coefficient of an identically oriented slab times the physical optics solution for the backscatter cross section of a perfectly conducting disk of the same shape. This result follows directly from the Kirchhoff type approximation without additional assumptions.

  4. MODELING AND FISSION CROSS SECTIONS FOR AMERICIUM.

    SciTech Connect

    ROCHMAN, D.; HERMAN, M.; OBLOZINSKY, P.

    2005-05-01

    This is the final report of the work performed under the LANL contract on the modeling and fission cross section for americium isotopes (May 2004-June 2005). The purpose of the contract was to provide fission cross sections for americium isotopes with the nuclear reaction model code EMPIRE 2.19. The following work was performed: (1) Fission calculations capability suitable for americium was implemented to the EMPIRE-2.19 code. (2) Calculations of neutron-induced fission cross sections for {sup 239}Am to {sup 244g}Am were performed with EMPIRE-2.19 for energies up to 20 MeV. For the neutron-induced reaction of {sup 240}Am, fission cross sections were predicted and uncertainties were assessed. (3) Set of fission barrier heights for each americium isotopes was chosen so that the new calculations fit the experimental data and follow the systematics found in the literature.

  5. Absorption cross section of canonical acoustic holes

    SciTech Connect

    Crispino, Luis C. B.; Oliveira, Ednilton S.; Matsas, George E. A.

    2007-11-15

    We compute numerically the absorption cross section of a canonical acoustic hole for sound waves with arbitrary frequencies. Our outputs are in full agreement with the expected low- and high-frequency limits.

  6. Bibliography of photoabsorption cross-section data

    NASA Technical Reports Server (NTRS)

    Hudson, R. D.; Kieffer, L. J.

    1970-01-01

    This bibliography contains only references which report a measured or calculated photoabsorption cross section (relative or normalized) in regions of continuous absorption. The bibliography is current as of January 1, 1970.

  7. Shuttle orbiter radar cross-sectional analysis

    NASA Technical Reports Server (NTRS)

    Cooper, D. W.; James, R.

    1979-01-01

    Theoretical and model simulation studies on signal to noise levels and shuttle radar cross section are described. Pre-mission system calibrations, system configuration, and postmission system calibration of the tracking radars are described. Conversion of target range, azimuth, and elevation into radar centered east north vertical position coordinates are evaluated. The location of the impinging rf energy with respect to the target vehicles body axis triad is calculated. Cross section correlation between the two radars is presented.

  8. Reaction cross sections of unstable nuclei

    SciTech Connect

    Ozawa, Akira

    2006-11-02

    Experimental studies on reaction cross sections are reviewed. The recent developments of radioactive nuclear beams have enabled us to measure reaction cross-sections for unstable nuclei. Using Glauber-model analysis, effective nuclear matter density distributions of unstable nuclei can be studied. Recent measurements in RIBLL at IMP and RIPS at RIKEN are introduced. The effective matter density distributions for 14-18C are also mentioned.

  9. Ultraviolet absorption cross sections of hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Lin, C. L.; Rohatgi, N. K.; Demore, W. B.

    1978-01-01

    Absorption cross-sections of hydrogen peroxide vapor and of neutral aqueous solutions of hydrogen peroxide were measured in the wavelength range from 195 to 350 nm at 296 K. The spectrophotometric procedure is described, and the reported cross-sections are compared with values obtained by other researchers. Photodissociation coefficients of atmospheric H2O2 were calculated for direct absorption of unscattered solar radiation, and the vertical distributions of these coefficients are shown for various solar zenith angles.

  10. 14 CFR Section 04 - Air Carrier Groupings

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 4 2014-01-01 2014-01-01 false Air Carrier Groupings Section 04 Section 04... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS Section 04 Air Carrier Groupings (a) All large certificated air carriers are placed into three basic air carrier groupings...

  11. 14 CFR Section 04 - Air Carrier Groupings

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 4 2013-01-01 2013-01-01 false Air Carrier Groupings Section 04 Section 04... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS Section 04 Air Carrier Groupings (a) All large certificated air carriers are placed into three basic air carrier groupings...

  12. 14 CFR Section 04 - Air Carrier Groupings

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false Air Carrier Groupings Section 04 Section 04... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS Section 04 Air Carrier Groupings (a) All large certificated air carriers are placed into three basic air carrier groupings...

  13. 14 CFR Section 04 - Air Carrier Groupings

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false Air Carrier Groupings Section 04 Section 04... REGULATIONS UNIFORM SYSTEM OF ACCOUNTS AND REPORTS FOR LARGE CERTIFICATED AIR CARRIERS Section 04 Air Carrier Groupings (a) All large certificated air carriers are placed into three basic air carrier groupings...

  14. Predicting the Total Charm Cross Section

    SciTech Connect

    Vogt, R

    2008-05-29

    We discuss the energy dependence of the total charm cross section and some of its theoretical uncertainties including the quark mass, scale choice and the parton densities. Extracting the total charm cross section from data is a non-trivial task. To go from a finite number of measured D mesons in a particular decay channel to the total c{bar c} cross section one must: divide by the branching ratio for that channel; correct for the luminosity, {sigma}{sub D} = N{sub D}/Lt; extrapolate to full phase space from the finite detector acceptance; divide by two to get the pair cross section from the single Ds; and multiply by a correction factor to account for unmeasured charm hadrons. Early fixed-target data were at rather low p{sub T}, making the charm quark mass the most relevant scale. At proton and ion colliders, although the RHIC experiments can access the full pT range and thus the total cross section, the data reach rather high p{sub T}, p{sub T} >> m, making p{sub T} (m{sub T}) the most relevant scale. Here we focus on the total cross section calculation where the quark mass is the only relevant scale.

  15. QuickSite Cross Section Processing

    Energy Science and Technology Software Center (ESTSC)

    2003-05-27

    This AGEM-developed system produces cross sections by inputting data in both standard and custom file formats and outputting a graphic file that can be printed or further modified in a commercial graphic program. The system has evolved over several years in order to combine and visualize a changing set of field data more rapidly than was possible with commercially available cross section software packages. It uses some commercial packages to produce the input and tomore » modify the output files. Flexibility is provided by a dynamic set of programs that are customized to accept varying input and accomodate varying output requirements. There are two basic types of routines: conversion routines and cross section generation routines. The conversion routines convery various data files to logger file format which is compatible with a standard file format for LogPlot 98, a commonly used commercial log plotting program. The cross section routines generate cross sections and apply topography to these cross sections. All of the generation routines produce a standard graphic DXF file, which is the format used in AutoCAD and can then be modified in a number of available graphics programs.« less

  16. abo-cross: Hydrogen broadening cross-section calculator

    NASA Astrophysics Data System (ADS)

    Barklem, P. S.; Anstee, S. D.; O'Mara, B. J.

    2015-07-01

    Line broadening cross sections for the broadening of spectral lines by collisions with neutral hydrogen atoms have been tabulated by Anstee & O'Mara (1995), Barklem & O'Mara (1997) and Barklem, O'Mara & Ross (1998) for s-p, p-s, p-d, d-p, d-f and f-d transitions. abo-cross, written in Fortran, interpolates in these tabulations to make these data more accessible to the end user. This code can be incorporated into existing spectrum synthesis programs or used it in a stand-alone mode to compute line broadening cross sections for specific transitions.

  17. Revised cross section for RHIC dipole magnets

    SciTech Connect

    Thompson, P.A.; Gupta, R.C.; Kahn, S.A.; Hahn, H.; Morgan, G.H.; Wanderer, P.J.; Willen, E.

    1991-01-01

    Using the experience gained in designing and building Relativistic Heavy Ion Collider (RHIC) dipole prototype magnets an improved cross section has been developed. Significant features of this design include the use of only three wedges for field shaping and wedge cross sections which are sectors of an annulus. To aid in the understanding of the actual magnets, one has been sectioned, and detailed mechanical and photographic measurements made of the wire positions. The comparison of these measurements with the magnetic field measurements will is presented. 2 refs, 3 figs., 2 tabs.

  18. Actinide cross section program at ORELA

    SciTech Connect

    Dabbs, J.W.T.

    1980-01-01

    The actinide cross section program at ORELA, the Oak Ridge Electron Linear Accelerator, is aimed at obtaining accurate neutron cross sections (primarily fission, capture, and total) for actinide nuclides which occur in fission reactors. Such cross sections, measured as a function of neutron energy over as wide a range of energies as feasible, comprise a data base that permits calculated predictions of the formation and removal of these nuclides in reactors. The present program is funded by the Division of Basic Energy Sciences of DOE, and has components in several divisions at ORNL. For intensively ..cap alpha..-active nuclides, many of the existing fission cross section data have been provided by underground explosions. New measurement techniques, developed at ORELA, now permit linac measurements on fissionable nuclides with alpha half-lives as short as 28 years. Capture and capture-plus-fission measurements utilize scintillation detectors (of capture ..gamma.. rays and fission neutrons) in which pulse shape discrimination plays an important role. Total cross sections can be measured at ORELA on samples of only a few milligrams. A simultaneous program of chemical and isotopic analyses of samples irradiated in EBR-II is in progress to provide benchmarks for the existing differential measurements. These analyses are being studied with updated versions of ORIGEN and with sensitivity determinations. Calculations of the sensitivity to cross section changes of various aspects of the nuclear fuel cycle are also being made. Even in this relatively mature field, many cross sections still require improvements to provide an adequate data base. Examples of recent techniques and measurements are presented. 12 figures, 3 tables.

  19. Determinants of long acting and permanent contraceptive methods utilization among married women of reproductive age groups in western Ethiopia: a cross-sectional study

    PubMed Central

    Melka, Alemu Sufa; Tekelab, Tesfalidet; Wirtu, Desalegn

    2015-01-01

    Introduction In Ethiopia information on the level of utilization of the long term and permanent contraceptive methods and associated factorsis lacking. The aim of this study was to understand the determinant factors of long acting and permanent contraceptive methods use among married women of reproductive age in Western Ethiopia. Methods A community based cross- sectional study design was employed. Multi stage sampling was used to select 1003 study participants. Data was collected from April 10 to April 25,2014 using a pre- tested structured questionnaire. The data were entered using Epi-info version 3.5.1 and exported to SPSS version 20 for analysis. Multivariate logistic regression analysis was done to identify predictors of long acting and permanent contraceptive methods at 95% CL. Results Use of long acting and permanent contraceptive methods in this study was found to be 20%. Survey results showed a significant positive association between utilization of long acting and permanent contraceptive methods and women's education (AOR = 1.72, 95%CI = 1.02 - 3.05), women's occupation (AOR = 2.01, 95% CI = 1.11 -3.58), number of live children (AOR = 2.42, 95% CI: 1.46- 4.02), joint fertility related decision (AOR = 6.11, 95% CI: 2.29- 16.30), having radio/TV (AOR = 2.31, 95% CI: 1.40 - 3.80), and discussion with health care provider about long acting and permanent contraceptive methods (AOR = 13.72, 95% CI: 8.37 - 22.47). Conclusion Efforts need to be aimed at women empowerment, health education, and encouraging open discussion of family planning by couples PMID:26523185

  20. Psychosocial risk factors, job characteristics and self-reported health in the Paris Military Hospital Group (PMHG): a cross-sectional study

    PubMed Central

    Verret, Catherine; Trichereau, Julie; Rondier, Jean-Philippe; Viance, Patrice; Migliani, René

    2012-01-01

    Objectives To investigate the associations between psychosocial risk factors and self-reported health, taking into account other occupational risk factors. Design Cross-sectional survey using a self-administered questionnaire. Setting The three military hospitals in Paris, France. Participants Surveys were distributed to 3173 employees (1807 military and 1336 civilian), a total of 1728 employees completed surveys. Missing data prohibited the use of 26 surveys. Primary and secondary outcome measures The authors used Karasek's model in order to identify psychosocial factors (psychological demands, decisional latitude, social support) in the workplace. The health indicator studied was self-reported health. Adjustments were made for covariates: age, gender, civil or military status, work injury, ergonomic score, physical and chemical exposures, and occupational profile. Occupational profile was defined by professional category, department, work schedule, supervisor status and service-related length in the hospital. Results Job strain (defined as high psychological demands and low decisional latitude) (adjusted OR 2.1, 95% CI 1.5 to 2.8, p<0.001) and iso-strain (job strain with low social support) were significantly associated with moderate or poor self-reported health. Among covariates, occupational profile (p<0.001) and an unsatisfactory ergonomic score (adjusted OR 2.3 95% CI 1.6 to 3.2, p<0.001) were also significantly associated with moderate or poor self-reported health. Conclusions The results support findings linking moderate or poor self-reported health to psychosocial risk factors. The results of this study suggest that workplace interventions that aim to reduce exposure to psychological demands as well as to increase decisional latitude and social support could help improve self-reported health. PMID:22855624

  1. Undergraduate Measurements of Neutron Cross Sections

    NASA Astrophysics Data System (ADS)

    Hicks, S. F.; Vanhoy, J. R.; French, A. J.; Santonil, Z. C.; Crider, B. P.; Peters, E. E.; McEllistrem, M. T.; Prados-Estévez, F. M.; Ross, T. J.; Yates, S. W.

    Undergraduate students at the University of Dallas have investigated basic properties of nuclei through γ-ray and neutron spectroscopy following neutron scattering. The former has been used primarily for nuclear structure investigations, while the latter has been used to measure neutron scattering cross sections important for fission reactor applications. A series of (n,n') and (n,n'γ) measurements have been made on 54Fe and 56Fe to determine neutron cross sections for scattering to excited levels in these nuclei. The former provides the cross sections directly and the latter are used to deduce inelastic neutron scattering cross sections by measuring the γ-ray production cross sections to states not easily resolved in neutron spectroscopy. All measurements have been completed at the University of Kentucky Accelerator Laboratory using a 7-MV Model CN Van de Graaff accelerator, along with the neutron production and neutron and γ-ray detection systems located there. Students participate in accelerator operation, experimental setup, data acquisition, and data analyses. An overview of the research program and student contributions is presented.

  2. Reduction Methods for Total Reaction Cross Sections

    NASA Astrophysics Data System (ADS)

    Gomes, P. R. S.; Mendes Junior, D. R.; Canto, L. F.; Lubian, J.; de Faria, P. N.

    2016-03-01

    The most frequently used methods to reduce fusion and total reaction excitation functions were investigated in a very recent paper Canto et al. (Phys Rev C 92:014626, 2015). These methods are widely used to eliminate the influence of masses and charges in comparisons of cross sections for weakly bound and tightly bound systems. This study reached two main conclusions. The first is that the fusion function method is the most successful procedure to reduce fusion cross sections. Applying this method to theoretical cross sections of single channel calculations, one obtains a system independent curve (the fusion function), that can be used as a benchmark to fusion data. The second conclusion was that none of the reduction methods available in the literature is able to provide a universal curve for total reaction cross sections. The reduced single channel cross sections keep a strong dependence of the atomic and mass numbers of the collision partners, except for systems in the same mass range. In the present work we pursue this problem further, applying the reduction methods to systems within a limited mass range. We show that, under these circumstances, the reduction of reaction data may be very useful.

  3. Modeling the heavy ion upset cross section

    NASA Astrophysics Data System (ADS)

    Connell, L. W.; McDaniel, P. J.; Prinja, A. K.; Sexton, F. W.

    1995-04-01

    The standard Rectangular Parallelepiped (RPP) construct is used to derive a closed form expression for, sigma-bar (theta, phi, L) the directional-spectral heavy ion upset cross section. This is an expected value model obtained by integrating the point-value cross section model, sigma (theta, phi, L, E), also developed here, with the Weibull density function, f(E), assumed to govern the stochastic behavior of the upset threshold energy, E. A comparison of sigma-bar (theta, phi, L) with experimental data show good agreement, lending strong credibility to the hypothesis that E-randomness is responsible for the shape of the upset cross section curve. The expected value model is used as the basis for a new, rigorous mathematical formulation of the effective cross section concept. The generalized formulation unifies previous corrections to the inverse cosine scaling, collapsing to Petersen's correction, (cos theta - (h/l) sin theta)(sup -1), near threshold and Sexton's, (cos theta + (h/l) sin theta)(sup -1), near saturation. The expected value cross section model therefore has useful applications in both upset rate prediction and test data analysis.

  4. Algorithmic analysis of quantum radar cross sections

    NASA Astrophysics Data System (ADS)

    Lanzagorta, Marco; Venegas-Andraca, Salvador

    2015-05-01

    Sidelobe structures on classical radar cross section graphs are a consequence of discontinuities in the surface currents. In contrast, quantum radar theory states that sidelobe structures on quantum radar cross section graphs are due to quantum interference. Moreover, it is conjectured that quantum sidelobe structures may be used to detect targets oriented off the specular direction. Because of the high data bandwidth expected from quantum radar, it may be necessary to use sophisticated quantum signal analysis algorithms to determine the presence of stealth targets through the sidelobe structures. In this paper we introduce three potential quantum algorithmic techniques to compute classical and quantum radar cross sections. It is our purpose to develop a computer science-oriented tool for further physical analysis of quantum radar models as well as applications of quantum radar technology in various fields.

  5. The cross section for double Compton scattering

    NASA Technical Reports Server (NTRS)

    Gould, R. J.

    1984-01-01

    Employing elementary methods in nonrelativistic quantum electrodynamics, the cross section for gamma sub 0 + e yields e + gamma + gamma is computed for arbitrary energy in the spectrum of the outgoing photons. The final result is given, differential in the energy of one of these photons, for the case where the incident photon is unpolarized and has energy E sub 0 much less than mc-squared, a polarization sum and angular integration being performed for the final-state photons. The cross section has a simple algebraic form resulting from contributions from the sum of squared direct and exchange amplitudes; interference terms from these amplitudes do not contribute to the angular-integrated cross section.

  6. Top differential cross section measurements (Tevatron)

    SciTech Connect

    Jung, Andreas W.

    2012-01-01

    Differential cross sections in the top quark sector measured at the Fermilab Tevatron collider are presented. CDF used 2.7 fb{sup -1} of data and measured the differential cross section as a function of the invariant mass of the t{bar t} system. The measurement shows good agreement with the standard model and furthermore is used to derive limits on the ratio {kappa}/M{sub Pl} for gravitons which decay to top quarks in the Randall-Sundrum model. D0 used 1.0 fb{sup -1} of data to measure the differential cross section as a function of the transverse momentum of the top-quark. The measurement shows a good agreement to the next-to-leading order perturbative QCD prediction and various other standard model predictions.

  7. Chronic disease prevalence and care among the elderly in urban and rural Beijing, China - a 10/66 Dementia Research Group cross-sectional survey

    PubMed Central

    Liu, Zhaorui; Albanese, Emiliano; Li, Shuran; Huang, Yueqin; Ferri, Cleusa P; Yan, Fang; Sousa, Renata; Dang, Weimin; Prince, Martin

    2009-01-01

    Background Demographic ageing is occurring at an unprecedented rate in China. Chronic diseases and their disabling consequences will become much more common. Public policy has a strong urban bias, and older people living in rural areas may be especially vulnerable due to limited access to good quality healthcare, and low pension coverage. We aim to compare the sociodemographic and health characteristics, health service utilization, needs for care and informal care arrangements of representative samples of older people in two Beijing communities, urban Xicheng and rural Daxing. Methods A one-phase cross-sectional survey of all those aged 65 years and over was conducted in urban and rural catchment areas in Beijing, China. Assessments included questionnaires, a clinical interview, physical examination, and an informant interview. Prevalence of chronic diseases, self-reported impairments and risk behaviours was calculated adjusting for household clustering. Poisson working models were used to estimate the independent effect of rural versus urban residence, and to explore the predictors of health services utilization. Results We interviewed 1002 participants in rural Daxing, and 1160 in urban Xicheng. Those in Daxing were more likely to be younger, widowed, less educated, not receiving a pension, and reliant on family transfers. Chronic diseases were more common in Xicheng, when based on self-report rather than clinical assessment. Risk exposures were more common in Daxing. Rural older people were much less likely to access health services, controlling for age and health. Community health services were ineffective, particularly in Daxing, where fewer than 3% of those with hypertension were adequately controlled. In Daxing, care was provided by family, who had often given up work to do so. In Xicheng, 45% of those needing care were supported by paid caregivers. Caregiver strain was higher in Xicheng. Dementia was strongly associated with care needs and caregiver strain

  8. New Parameterization of Neutron Absorption Cross Sections

    NASA Technical Reports Server (NTRS)

    Tripathi, Ram K.; Wilson, John W.; Cucinotta, Francis A.

    1997-01-01

    Recent parameterization of absorption cross sections for any system of charged ion collisions, including proton-nucleus collisions, is extended for neutron-nucleus collisions valid from approx. 1 MeV to a few GeV, thus providing a comprehensive picture of absorption cross sections for any system of collision pairs (charged or uncharged). The parameters are associated with the physics of the problem. At lower energies, optical potential at the surface is important, and the Pauli operator plays an increasingly important role at intermediate energies. The agreement between the calculated and experimental data is better than earlier published results.

  9. Precise neutron inelastic cross section measurements

    SciTech Connect

    Negret, Alexandru

    2012-11-20

    The design of a new generation of nuclear reactors requires the development of a very precise neutron cross section database. Ongoing experiments performed at dedicated facilities aim to the measurement of such cross sections with an unprecedented uncertainty of the order of 5% or even smaller. We give an overview of such a facility: the Gamma Array for Inelastic Neutron Scattering (GAINS) installed at the GELINA neutron source of IRMM, Belgium. Some of the most challenging difficulties of the experimental approach are emphasized and recent results are shown.

  10. Cross sections of neutron-induced reactions

    SciTech Connect

    Mukhopadhyay, Tapan; Lahiri, Joydev; Basu, D. N.

    2010-10-15

    We study the properties of the neutron-nucleus total and reaction cross sections for several nuclei. We have applied an analytical model, the nuclear Ramsauer model, justified it from the nuclear reaction theory approach, and extracted the values of 12 parameters used in the model. The given parametrization has an advantage as phenomenological optical model potentials are limited up to 150-200 MeV. The present model provides good estimates of the total cross sections for several nuclei particularly at high energies.

  11. Covariance Evaluation Methodology for Neutron Cross Sections

    SciTech Connect

    Herman,M.; Arcilla, R.; Mattoon, C.M.; Mughabghab, S.F.; Oblozinsky, P.; Pigni, M.; Pritychenko, b.; Songzoni, A.A.

    2008-09-01

    We present the NNDC-BNL methodology for estimating neutron cross section covariances in thermal, resolved resonance, unresolved resonance and fast neutron regions. The three key elements of the methodology are Atlas of Neutron Resonances, nuclear reaction code EMPIRE, and the Bayesian code implementing Kalman filter concept. The covariance data processing, visualization and distribution capabilities are integral components of the NNDC methodology. We illustrate its application on examples including relatively detailed evaluation of covariances for two individual nuclei and massive production of simple covariance estimates for 307 materials. Certain peculiarities regarding evaluation of covariances for resolved resonances and the consistency between resonance parameter uncertainties and thermal cross section uncertainties are also discussed.

  12. Neutron capture cross section of 136 Xe

    NASA Astrophysics Data System (ADS)

    Daugherty, Sean; Albert, Joshua; Johnson, Tessa; O'Conner, Thomasina; Kaufman, Lisa

    2015-04-01

    136 Xe is an important 0 νββ candidate, studied in experiments such as EXO-200 and, in the future, nEXO. These experiments require a precise study of neutron capture for their background models. The neutron capture cross section of 136 Xe has been measured at the Detector for Advanced Capture Experiments (DANCE) at the Los Alamos Neutron Science Center. A neutron beam ranging from thermal energy to 100 keV was incident on a gas cell filled with isotopically pure 136 Xe . We will discuss the measurement of partial neutron capture cross sections at thermal and first neutron resonance energies along with corresponding capture gamma cascades.

  13. Neutron Capture Cross Section of 239Pu

    NASA Astrophysics Data System (ADS)

    Mosby, S.; Arnold, C.; Bredeweg, T. A.; Couture, A.; Jandel, M.; O'Donnell, J. M.; Rusev, G.; Ullmann, J. L.; Chyzh, A.; Henderson, R.; Kwan, E.; Wu, C. Y.

    2014-09-01

    The 239Pu(n,γ) cross section has been measured over the energy range 10 eV - 10 keV using the Detector for Advanced Neutron Capture Experiments (DANCE) as part of a campaign to produce precision (n,γ) measurements on 239Pu in the keV region. Fission coincidences were measured with a PPAC and used to characterize the prompt fission γ-ray spectrum in this region. The resulting spectra will be used to better characterize the fission component of another experiment with a thicker target to extend the (n,γ) cross section measurement well into the keV region.

  14. Optical Model and Cross Section Uncertainties

    SciTech Connect

    Herman,M.W.; Pigni, M.T.; Dietrich, F.S.; Oblozinsky, P.

    2009-10-05

    Distinct minima and maxima in the neutron total cross section uncertainties were observed in model calculations using spherical optical potential. We found this oscillating structure to be a general feature of quantum mechanical wave scattering. Specifically, we analyzed neutron interaction with 56Fe from 1 keV up to 65 MeV, and investigated physical origin of the minima.We discuss their potential importance for practical applications as well as the implications for the uncertainties in total and absorption cross sections.

  15. Infrared absorption cross sections of alternative CFCs

    NASA Technical Reports Server (NTRS)

    Clerbaux, Cathy; Colin, Reginald; Simon, Paul C.

    1994-01-01

    Absorption cross sections have obtained in the infrared atmospheric window, between 600 and 1500 cm(exp -1), for 10 alternative hydrohalocarbons: HCFC-22, HCFC-123, HCFC-124, HCFC-141b, HCFC-142b, HCFC-225ca, HCFC-225cb, HFC-125, HFC-134a, and HFC-152a. The measurements were made at three temperatures (287K, 270K and 253K) with a Fourier transform spectrometer operating at 0.03 cm(exp -1) apodized resolution. Integrated cross sections are also derived for use in radiative models to calculate the global warming potentials.

  16. Cross sections for actinide burner reactors

    SciTech Connect

    Difilippo, F.C.

    1991-01-01

    Recent studies have shown the feasibility of burning higher actinides (i.e., transuranium (TRU) elements excluding plutonium) in ad hoc designed reactors (Actinide Burner Reactors: ABR) which, because of their hard neutron spectra, enhance the fission of TRU. The transmutation of long-lived radionuclides into stable or short-lived isotopes reduces considerably the burden of handling high-level waste from either LWR or Fast Breeder Reactors (FBR) fuels. Because of the large concentrations of higher actinides in these novel reactor designs the Doppler effect due to TRU materials is the most important temperature coefficient from the point of view of reactor safety. Here we report calculations of energy group-averaged capture and fission cross sections as function of temperature and dilution for higher actinides in the resolved and unresolved resonance regions. The calculations were done with the codes SAMMY in the resolved region and URR in the unresolved regions and compared with an independent calculation. 4 refs., 2 figs., 2 tabs.

  17. Testing (Validating?) Cross Sections with ICSBEP Benchmarks

    SciTech Connect

    Kahler, Albert C. III

    2012-06-28

    We discuss how to use critical benchmarks from the International Handbook of Evaluated Criticality Safety Benchmark Experiments to determine the applicability of specific cross sections to the end-user's problem of interest. Particular attention is paid to making sure the selected suite of benchmarks includes the user's range of applicability (ROA).

  18. Cross-sectional structural parameters from densitometry

    NASA Technical Reports Server (NTRS)

    Cleek, Tammy M.; Whalen, Robert T.

    2002-01-01

    Bone densitometry has previously been used to obtain cross-sectional properties of bone from a single X-ray projection across the bone width. Using three unique projections, we have extended the method to obtain the principal area moments of inertia and orientations of the principal axes at each scan cross-section along the length of the scan. Various aluminum phantoms were used to examine scanner characteristics to develop the highest accuracy possible for in vitro non-invasive analysis of cross-sectional properties. Factors considered included X-ray photon energy, initial scan orientation, the angle spanned by the three scans (included angle), and I(min)/I(max) ratios. Principal moments of inertia were accurate to within +/-3.1% and principal angles were within +/-1 degrees of the expected value for phantoms scanned with included angles of 60 degrees and 90 degrees at the higher X-ray photon energy (140 kVp). Low standard deviations in the error (0.68-1.84%) also indicate high precision of calculated measurements with these included angles. Accuracy and precision decreased slightly when the included angle was reduced to 30 degrees. The method was then successfully applied to a pair of excised cadaveric tibiae. The accuracy and insensitivity of the algorithms to cross-sectional shape and changing isotropy (I(min)/I(max)) values when various included angles are used make this technique viable for future in vivo studies.

  19. Cross sections relevant to gamma ray astronomy

    NASA Technical Reports Server (NTRS)

    Dyer, P.; Bodansky, D.; Maxson, D. R.

    1978-01-01

    Gamma-ray production cross sections were measured for protons and alpha particles incident on targets consisting of nuclei of high cosmic abundance: C-12, N-14, O-16, Ne-20, Mg-24, Si-28 and Fe-56. Solid or gaseous targets were bombarded by monoenergetic beams of protons and alpha particles, and gamma rays were detected by two Ge(Li) detectors. The proton energy for each target was varied from threshold to about 24 MeV (lab); for alphas the range was from threshold to about 27 MeV. For most transitions, it was possible to measure the total cross section by placing the detectors at 30.5 deg and 109.9 deg where the fourth-order Legendre polynomial is zero. For the case of the 16O (E sub gamma = 6.13 MeV, multipolarity E3) cross sections, yields were measured at four angles. Absolute cross sections were obtained by integrating the beam current and by measuring target thicknesses and detector efficiencies. The Ge(Li) detector resolution was a few keV (although the peak widths were greater, due to Doppler broadening).

  20. Photoelectric absorption cross sections with variable abundances

    NASA Technical Reports Server (NTRS)

    Balucinska-Church, Monika; Mccammon, Dan

    1992-01-01

    Polynomial fit coefficients have been obtained for the energy dependences of the photoelectric absorption cross sections of 17 astrophysically important elements. These results allow the calculation of X-ray absorption in the energy range 0.03-10 keV in material with noncosmic abundances.

  1. Cross Sections From Scalar Field Theory

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Dick, Frank; Norman, Ryan B.; Nasto, Rachel

    2008-01-01

    A one pion exchange scalar model is used to calculate differential and total cross sections for pion production through nucleon- nucleon collisions. The collisions involve intermediate delta particle production and decay to nucleons and a pion. The model provides the basic theoretical framework for scalar field theory and can be applied to particle production processes where the effects of spin can be neglected.

  2. Neutron Capture Cross Sections for Radioactive Nuclei

    NASA Astrophysics Data System (ADS)

    Tonchev, Anton; Bedrossian, Peter; Escher, Jutta; Scielzo, Nicholas

    2015-10-01

    Accurate neutron-capture cross sections for radioactive nuclei near or far away from the line of beta stability are crucial for understanding the nucleosynthesis of heavy elements. However, neutron-capture cross sections for short-lived radionuclides are difficult to measure due to the fact that the measurements require both highly radioactive samples and intense neutron sources. Essential ingredients for describing the γ decays following neutron capture are the γ-ray strength function and level densities. We will compare different indirect approaches for obtaining observables that can constrain Hauser-Feshbach statistical model calculations of capture cross sections. Specifically, we will consider photon scattering, transfer reactions, and beta-delayed neutron emission. Challenges that exist on the path to obtaining neutron-capture cross sections for reactions on isotopes far from stability will be discussed. This work was performed under the auspices of US DOE by LLNL under contract DE-AC52-07NA27344. Funding was provided via the LDRD-ERD-069 project.

  3. Electron impact excitation cross sections for carbon

    NASA Astrophysics Data System (ADS)

    Ganas, P. S.

    1981-04-01

    A realistic analytic atomic independent particle model is used to generate wave functions for the valence and excited states of carbon. Using these wave functions in conjunction with the Born approximation and the Russell-Saunders LS-coupling scheme, we calculate generalized oscillator strengths and integrated cross sections for various excitations from the 2p 2( 3P O) valence state.

  4. A Multilevel Approach on Self-Reported Dental Caries in Subjects of Minority Ethnic Groups: A Cross-Sectional Study of 6440 Adults.

    PubMed

    Ardila, Carlos M; Posada-López, Adriana; Agudelo-Suárez, Andrés A

    2016-02-01

    Regional contextual factors and dental caries using multilevel modeling related to adults in minority ethnic groups have been scantily explored. The influence of the socioeconomic context on self-reported dental caries (SRDC) in individuals of minority ethnic groups (IEG) in Colombia was studied. Data from the 2007 National Public Health Survey were collected in 34,843 participants of the population. The influence of different factors on SRDC in IEG was investigated with logistic and multilevel regression analyses. A total of 6440 individuals belonged to an ethnic group. Multilevel analysis showed a significant variance in SRDC that was smaller in IEG level than between states. Multilevel multivariate analysis also associated SRDC with increasing age, lower education level, last dental visit >1 year, unmet dental need and low Gross Domestic Product (GDP). Minority ethnic groups were at risk to report higher dental caries, where low GDP was an important variable to be considered. PMID:25963050

  5. Differential Cross Sections for Positrons Scattered from Molecules

    NASA Astrophysics Data System (ADS)

    Przybyla, D. A.; Addo-Asah, W.; Kauppila, W. E.; Stein, T. S.

    1998-05-01

    We have measured relative quasi-elastic (elastic scattering plus vibrational and rotational excitations) differential cross sections (DCS's) for positrons scattered at 30^o to 135^o from CH_4, N_2, O_2, CO, CO2 , and SF6 at energies extending from below the positronium (Ps) formation thresholds to well above them.(D. A. Przybyla, Nucl. Instr. and Meth. in Phys. Res. B, to be pub.) For each molecule we find (by extrapolating our DCS's to 0^o and 180^o) that below the Ps formation threshold there are significant large angle contributions to the total quasi-elastic cross sections. This observation is consistent with Ps formation cross sections measured by our group(C. K. Kwan, Nucl. Instr. and Meth. in Phys. Res. B, to be pub.), where we make "upper limit" measurements using a beam-transmisson technique with the angular discrimination deliberately made as poor as possible. In that case, there are still significant upper limit cross section values below the Ps formation threshold which must be due to elastically scattered positrons removed from the beam by scattering into large angles and the backward hemisphere. Below the Ps formation threshold, molecules with the greatest large angle DCS's have "upper limit" cross sections that are the greatest percentage of the total cross section.

  6. Validation of the Monte Carlo criticality program KENO IV and the Hansen-Roach sixteen-energy-group-cross sections for high-assay uranium systems. [KENO IV criticality code

    SciTech Connect

    Handley, G. R.; Masters, L. C.; Stachowiak, R. V.

    1981-04-10

    Validation of the Monte Carlo criticality code, KENO IV, and the Hansen-Roach sixteen-energy-group cross sections was accomplished by calculating the effective neutron multiplication constant, k/sub eff/, of 29 experimentally critical assemblies which had uranium enrichments of 92.6% or higher in the uranium-235 isotope. The experiments were chosen so that a large variety of geometries and of neutron energy spectra were covered. Problems, calculating the k/sub eff/ of systems with high-uranium-concentration uranyl nitrate solution that were minimally reflected or unreflected, resulted in the separate examination of five cases.

  7. BUGJEFF311.BOLIB (JEFF-3.1.1) and BUGENDF70.BOLIB (ENDF/B-VII.0) - Generation Methodology and Preliminary Testing of two ENEA-Bologna Group Cross Section Libraries for LWR Shielding and Pressure Vessel Dosimetry

    NASA Astrophysics Data System (ADS)

    Pescarini, Massimo; Sinitsa, Valentin; Orsi, Roberto; Frisoni, Manuela

    2016-02-01

    Two broad-group coupled neutron/photon working cross section libraries in FIDO-ANISN format, dedicated to LWR shielding and pressure vessel dosimetry applications, were generated following the methodology recommended by the US ANSI/ANS-6.1.2-1999 (R2009) standard. These libraries, named BUGJEFF311.BOLIB and BUGENDF70.BOLIB, are respectively based on JEFF-3.1.1 and ENDF/B-VII.0 nuclear data and adopt the same broad-group energy structure (47 n + 20 γ) of the ORNL BUGLE-96 similar library. They were respectively obtained from the ENEA-Bologna VITJEFF311.BOLIB and VITENDF70.BOLIB libraries in AMPX format for nuclear fission applications through problem-dependent cross section collapsing with the ENEA-Bologna 2007 revision of the ORNL SCAMPI nuclear data processing system. Both previous libraries are based on the Bondarenko self-shielding factor method and have the same AMPX format and fine-group energy structure (199 n + 42 γ) as the ORNL VITAMIN-B6 similar library from which BUGLE-96 was obtained at ORNL. A synthesis of a preliminary validation of the cited BUGLE-type libraries, performed through 3D fixed source transport calculations with the ORNL TORT-3.2 SN code, is included. The calculations were dedicated to the PCA-Replica 12/13 and VENUS-3 engineering neutron shielding benchmark experiments, specifically conceived to test the accuracy of nuclear data and transport codes in LWR shielding and radiation damage analyses.

  8. Learning of cross-sectional anatomy using clay models.

    PubMed

    Oh, Chang-Seok; Kim, Ji-Young; Choe, Yeon Hyeon

    2009-01-01

    We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students in a clay modeling group responded positively to this approach, and their average score on CT examination was higher than that of a group that did not use clay models. Clay modeling appears to be a useful supplement to conventional anatomy or radiologic anatomy education. It can be applied to any part of human body, and its effectiveness will be greater when a more complicated understanding of cross-sectional anatomy is required. PMID:19588481

  9. Absolute np and pp cross section determinations aimed at improving the standard for cross section measurements

    SciTech Connect

    Laptev, Alexander B; Haight, Robert C; Tovesson, Fredrik; Arndt, Richard A; Briscoe, William J; Paris, Mark W; Strakovsky, Igor I; Workman, Ron L

    2010-01-01

    Purpose of present research is a keeping improvement of the standard for cross section measurements of neutron-induced reactions. The cross sections for np and pp scattering below 1000 MeV are determined based on partial-wave analyses (PW As) of nucleon-nucleon scattering data. These cross sections are compared with the most recent ENDF/B-V11.0 and JENDL-4.0 data files, and the Nijmegen PWA. Also a comparison of evaluated data with recent experimental data was made to check a quality of evaluation. Excellent agreement was found between the new experimental data and our PWA predictions.

  10. Absolute np and pp Cross Section Determinations Aimed At Improving The Standard For Cross Section Measurements

    SciTech Connect

    Laptev, A. B.; Haight, R. C.; Tovesson, F.; Arndt, R. A.; Briscoe, W. J.; Paris, M. W.; Strakovsky, I. I.; Workman, R. L.

    2011-06-01

    Purpose of present research is a keeping improvement of the standard for cross section measurements of neutron-induced reactions. The cross sections for np and pp scattering below 1 GeV are determined based on partial-wave analyses (PWAs) of nucleon-nucleon scattering data. These cross sections are compared with the most recent ENDF/B-VII.0 and JENDL-4.0 data files, and the Nijmegen PWA. Also a comparison of evaluated data with recent experimental data was made to check a quality of evaluation. Excellent agreement was found between the new experimental data and our PWA predictions.

  11. Tables of nuclear cross sections for galactic cosmic rays: Absorption cross sections

    NASA Technical Reports Server (NTRS)

    Townsend, L. W.; Wilson, J. W.

    1985-01-01

    A simple but comprehensive theory of nuclear reactions is presented. Extensive tables of nucleon, deuteron, and heavy-ion absorption cross sections over a broad range of energies are generated for use in cosmic ray shielding studies. Numerous comparisons of the calculated values with available experimental data show agreement to within 3 percent for energies above 80 MeV/nucleon and within approximately 10 percent for energies as low as 30 MeV/nucleon. These tables represent the culmination of the development of the absorption cross section formalism and supersede the preliminary absorption cross sections published previously in NASA TN D-8107, NASA TP-2138, and NASA TM-84636.

  12. Universal Parameterization of Absorption Cross Sections

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, Francis A.; Wilson, John W.

    1997-01-01

    This paper presents a simple universal parameterization of total reaction cross sections for any system of colliding nuclei that is valid for the entire energy range from a few AMeV to a few AGeV. The universal picture presented here treats proton-nucleus collision as a special case of nucleus-nucleus collision, where the projectile has charge and mass number of one. The parameters are associated with the physics of the collision system. In general terms, Coulomb interaction modifies cross sections at lower energies, and the effects of Pauli blocking are important at higher energies. The agreement between the calculated and experimental data is better than all earlier published results.

  13. Cross sections required for FMIT dosimetry

    SciTech Connect

    Gold, R.; McElroy, W.N.; Lippincott, E.P.; Mann, F.M.; Oberg, D.L.; Roberts, J.H.; Ruddy, F.H.

    1980-05-02

    The Fusion Materials Irradiation Test (FMIT) facility, currently under construction, is designed to produce a high flux of high energy neutrons for irradiation effects experiments on fusion reactor materials. Characterization of the flux-fluence-spectrum in this rapidly varying neutron field requires adaptation and extension of currently available dosimetry techniques. This characterization will be carried out by a combination of active, passive, and calculational dosimetry. The goal is to provide the experimenter with accurate neutron flux-fluence-spectra at all positions in the test cell. Plans have been completed for a number of experimental dosimetry stations and provision for these facilities has been incorporated into the FMIT design. Overall needs of the FMIT irradiation damage program delineate goal accuracies for dosimetry that, in turn, create new requirements for high energy neutron cross section data. Recommendations based on these needs have been derived for required cross section data and accuracies.

  14. Inclusive jet cross section at D0

    SciTech Connect

    Bhattacharjee, M.

    1996-09-01

    Preliminary measurement of the central ({vert_bar}{eta}{vert_bar} {<=} 0.5) inclusive jet cross sections for jet cone sizes of 1.0, 0.7, and 0.5 at D{null} based on the 1992-1993 (13.7 {ital pb}{sup -1}) and 1994-1995 (90 {ital pb}{sup -1}) data samples are presented. Comparisons to Next-to-Leading Order (NLO) Quantum Chromodynamics (QCD) calculations are made.

  15. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1985-01-01

    The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

  16. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1982-01-01

    The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

  17. {sup 231}Pa photofission cross section

    SciTech Connect

    Soldatov, A.S.; Rudnikov, V.E.; Smirenkin, G.N.

    1995-12-01

    The measurements of the {sup 231}Pa yield and cross section photofission in the energy range 7-9 MeV are presented. These measurements are a continuation of similar measurements performed for the {gamma}-ray energy range 4.8-7 MeV. The entire collection of experimental data which combine the results obtained in the present work and in Ref. 1 was analyzed.

  18. Neutron cross section standards and instrumentation

    NASA Astrophysics Data System (ADS)

    1992-09-01

    This report from the National Institute of Standards and Technology contains a summary of the accomplishments of the Neutron Cross Section Standards and Instrumentation Project during the second year of a three-year interagency agreement. This program includes a broad range of data measurements and evaluations. An emphasis has been focused on the (sup 10)B cross sections where serious discrepancies in the nuclear data base remain. In particular, there are important problems with the interpretation of the helium gas production associated with diagnostic measurements of interest in nuclear technology. The enhanced use of this isotope for medical treatment is also of significance. New measurements of neutron reaction cross sections for (sup 10)B are in progress in collaboration with scientists at the Oak Ridge National Laboratory. New experiments are in progress on the important dosimetry standards (sup 237)Np(n,f) and (sup 239)Pu(n,f) below 1 MeV neutron energy. In addition, new measurements of charged-particle production in basic biological elements for medical applications are underway. Further measurements are planned or in progress in collaborations which include fission fragment energy and angular distributions, and neutron energy spectra and angular distributions from neutron-induced fission. Also measurements of angular distributions of neutrons from scattering on protons, and determinations of capture cross section of gold are planned for a later time. Data evaluation will shift to include a unified international effort to motivate new measurements and evaluations. In response to the requests of the measurement community, NIST is beginning the formation of a national depository for fissionable isotope mass standards. This action will preserve for future measurements the valuable and irreplaceable critical samples whose masses and composition have been carefully determined and documented over the past 30 years of the nuclear program.

  19. How to Calculate Colourful Cross Sections Efficiently

    SciTech Connect

    Gleisberg, Tanju; Hoeche, Stefan; Krauss, Frank

    2008-09-03

    Different methods for the calculation of cross sections with many QCD particles are compared. To this end, CSW vertex rules, Berends-Giele recursion and Feynman-diagram based techniques are implemented as well as various methods for the treatment of colours and phase space integration. We find that typically there is only a small window of jet multiplicities, where the CSW technique has efficiencies comparable or better than both of the other two methods.

  20. Fusion cross sections measurements with MUSIC

    NASA Astrophysics Data System (ADS)

    Carnelli, P. F. F.; Fernández Niello, J. O.; Almaraz-Calderon, S.; Rehm, K. E.; Albers, M.; Digiovine, B.; Esbensen, H.; Henderson, D.; Jiang, C. L.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Ugalde, C.; Paul, M.; Alcorta, M.; Bertone, P. F.; Lai, J.; Marley, S. T.

    2014-09-01

    The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. The interaction between exotic nuclei plays an important role for understanding the reaction mechanism of the fusion processes as well as for the energy production in stars. With the advent of radioactive beams new frontiers for fusion reaction studies have become accessible. We have performed the first measurements of the total fusion cross sections in the systems 10 , 14 , 15C + 12C using a newly developed active target-detector system (MUSIC). Comparison of the obtained cross sections with theoretical predictions show a good agreement in the energy region accessible with existing radioactive beams. This type of comparison allows us to calibrate the calculations for cases that cannot be studied in the laboratory with the current experimental capabilities. The high efficiency of this active detector system will allow future measurements with even more neutron-rich isotopes. This work is supported by the U.S. DOE Office of Nuclear Physics under Contract No. DE-AC02-06CH11357 and the Universidad Nacional de San Martin, Argentina, Grant SJ10/39.

  1. Inclusive jet cross section measurement at CDF

    SciTech Connect

    Pagliarone, C.

    1996-08-01

    The CDF Collaboration has measured the inclusive jet cross section using 1992-93 collider data at 1.8 TeV. The CDF measurement is in very good agreement with NLO QCD predictions for transverse energies (E{sub T}) below 200 GeV. However, it is systematically higher than NLO QCD predictions for E{sub T} above 200 GeV.

  2. Quality Quantification of Evaluated Cross Section Covariances

    SciTech Connect

    Varet, S.; Dossantos-Uzarralde, P.

    2015-01-15

    Presently, several methods are used to estimate the covariance matrix of evaluated nuclear cross sections. Because the resulting covariance matrices can be different according to the method used and according to the assumptions of the method, we propose a general and objective approach to quantify the quality of the covariance estimation for evaluated cross sections. The first step consists in defining an objective criterion. The second step is computation of the criterion. In this paper the Kullback-Leibler distance is proposed for the quality quantification of a covariance matrix estimation and its inverse. It is based on the distance to the true covariance matrix. A method based on the bootstrap is presented for the estimation of this criterion, which can be applied with most methods for covariance matrix estimation and without the knowledge of the true covariance matrix. The full approach is illustrated on the {sup 85}Rb nucleus evaluations and the results are then used for a discussion on scoring and Monte Carlo approaches for covariance matrix estimation of the cross section evaluations.

  3. Validation of SCALE 4.0 -- CSAS25 module and the 27-group ENDF/B-IV cross-section library for low-enriched uranium systems

    SciTech Connect

    Jordan, W.C.

    1993-02-01

    A version of KENO V.a and the 27-group library in SCALE-4.0 were validated for use in evaluating the nuclear criticality safety of low-enriched uranium systems. A total of 59 critical systems were analyzed. A statistical analysis of the results was performed, and subcritical acceptanced criteria are established.

  4. Validation of SCALE 4. 0 -- CSAS25 module and the 27-group ENDF/B-IV cross-section library for low-enriched uranium systems

    SciTech Connect

    Jordan, W.C.

    1993-02-01

    A version of KENO V.a and the 27-group library in SCALE-4.0 were validated for use in evaluating the nuclear criticality safety of low-enriched uranium systems. A total of 59 critical systems were analyzed. A statistical analysis of the results was performed, and subcritical acceptanced criteria are established.

  5. BMI Group-Related Differences in Physical Fitness and Physical Activity in Preschool-Age Children: A Cross-Sectional Analysis

    ERIC Educational Resources Information Center

    Niederer, Iris; Kriemler, Susi; Zahner, Lukas; Burgi, Flavia; Ebenegger, Vincent; Marques- Vidal, Pedro; Puder, Jardena J.

    2012-01-01

    In the Ballabeina study, we investigated age- and BMI-group-related differences in aerobic fitness (20 m shuttle run), agility (obstacle course), dynamic (balance beam) and static balance (balance platform), and physical activity (PA, accelerometers) in 613 children (M age = 5.1 years, SD = 0.6). Normal weight (NW) children performed better than…

  6. Clinical, physical and lifestyle variables and relationship with cognition and mood in aging: a cross-sectional analysis of distinct educational groups

    PubMed Central

    Santos, Nadine C.; Costa, Patrício S.; Cunha, Pedro; Portugal-Nunes, Carlos; Amorim, Liliana; Cotter, Jorge; Cerqueira, João J.; Palha, Joana A.; Sousa, Nuno

    2013-01-01

    It is relevant to unravel the factors that may mediate the cognitive decline observed during aging. Previous reports indicate that education has a positive influence on cognitive performance, while age, female gender and, especially, depressed mood were associated with poorer performances across multiple cognitive dimensions (memory and general executive function). Herein, the present study aimed to characterize the cognitive performance of community-dwelling individuals within distinct educational groups categorized by the number of completed formal school years: “less than 4,” “4, completed primary education,” and “more than 4.” Participants (n = 1051) were randomly selected from local health registries and representative of the Portuguese population for age and gender. Neurocognitive and clinical assessments were conducted in local health care centers. Structural equation modeling was used to derive a cognitive score, and hierarchical linear regressions were conducted for each educational group. Education, age and depressed mood were significant variables in directly explaining the obtained cognitive score, while gender was found to be an indirect variable. In all educational groups, mood was the most significant factor with effect on cognitive performance. Specifically, a depressed mood led to lower cognitive performance. The clinical disease indices cardiac and stroke associated with a more negative mood, while moderate increases in BMI, alcohol consumption and physical activity associated positively with improved mood and thus benefitted cognitive performance. Results warrant further research on the cause-effect (longitudinal) relationship between clinical indices of disease and risk factors and mood and cognition throughout aging. PMID:24605100

  7. Three-Dimensional (X,Y,Z) Deterministic Analysis of the PCA-Replica Neutron Shielding Benchmark Experiment using the TORT-3.2 Code and Group Cross Section Libraries for LWR Shielding and Pressure Vessel Dosimetry

    NASA Astrophysics Data System (ADS)

    Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela

    2016-02-01

    The PCA-Replica 12/13 (H2O/Fe) neutron shielding benchmark experiment was analysed using the ORNL TORT-3.2 3D SN code. PCA-Replica, specifically conceived to test the accuracy of nuclear data and transport codes employed in LWR shielding and radiation damage calculations, reproduces a PWR ex-core radial geometry with alternate layers of water and steel including a PWR pressure vessel simulator. Three broad-group coupled neutron/photon working cross section libraries in FIDO-ANISN format with the same energy group structure (47 n + 20 γ) and based on different nuclear data were alternatively used: the ENEA BUGJEFF311.BOLIB (JEFF-3.1.1) and BUGENDF70.BOLIB (ENDF/B-VII.0) libraries and the ORNL BUGLE-96 (ENDF/B-VI.3) library. Dosimeter cross sections derived from the IAEA IRDF-2002 dosimetry file were employed. The calculated reaction rates for the Rh-103(n,n')Rh-103 m, In-115(n,n')In-115m and S-32(n,p)P-32 threshold activation dosimeters and the calculated neutron spectra are compared with the corresponding experimental results.

  8. Disparities in mammographic screening for Asian women in California: a cross-sectional analysis to identify meaningful groups for targeted intervention

    PubMed Central

    Gomez, Scarlett Lin; Tan, Susanna; Keegan, Theresa HM; Clarke, Christina A

    2007-01-01

    Background Breast cancer is the most commonly diagnosed cancer among the rapidly growing population of Asian Americans; it is also the most common cause of cancer mortality among Filipinas. Asian women continue to have lower rates of mammographic screening than women of most other racial/ethnic groups. While prior studies have described the effects of sociodemographic and other characteristics of women on non-adherence to screening guidelines, they have not identified the distinct segments of the population who remain at highest risk of not being screened. Methods To better describe characteristics of Asian women associated with not having a mammogram in the last two years, we applied recursive partitioning to population-based data (N = 1521) from the 2001 California Health Interview Survey (CHIS), for seven racial/ethnic groups of interest: Chinese, Japanese, Filipino, Korean, South Asian, Vietnamese, and all Asians combined. Results We identified two major subgroups of Asian women who reported not having a mammogram in the past two years and therefore, did not follow mammography screening recommendations: 1) women who have never had a pap exam to screen for cervical cancer (68% had no mammogram), and 2) women who have had a pap exam, but have no women's health issues (osteoporosis, using menopausal hormone therapies, and/or hysterectomy) nor a usual source of care (62% had no mammogram). Only 19% of Asian women who have had pap screening and have women's health issues did not have a mammogram in the past two years. In virtually all ethnic subgroups, having had pap or colorectal screening were the strongest delineators of mammography usage. Other characteristics of women least likely to have had a mammogram included: Chinese non-U.S. citizens or citizens without usual source of health care, Filipinas with no health insurance, Koreans without women's health issues and public or no health insurance, South Asians less than age 50 who were unemployed or non

  9. Malaria in pregnancy in rural Gabon: a cross-sectional survey on the impact of seasonality in high-risk groups

    PubMed Central

    2013-01-01

    Background Malaria remains one of the most important infectious diseases in pregnancy in sub-Saharan Africa. Whereas seasonal malaria chemoprevention is advocated as public health intervention for children in certain areas of highly seasonal malaria transmission, the impact of seasonality on malaria in pregnancy has not yet been investigated for stable, hyper-endemic transmission settings of Equatorial Africa. The aim of this study was to investigate the influence of seasonality on the prevalence of malaria in pregnancy in Gabon. Methods The study was conducted at a rural district hospital in Gabon between January 2008 and December 2011. At first antenatal care visits demographic data, parity, age, and gestational age of pregnant women were documented and thick blood smears were performed for the diagnosis of malaria. Seasonality and established risk factors were evaluated in univariate and multivariate analysis for their association with Plasmodium falciparum infection. Results 1,661 pregnant women were enrolled in this study. Participants presenting during high transmission seasons were at significantly higher risk for P. falciparum infection compared to low transmission seasons (adjusted odds ratio [AOR] 1.91, 95% confidence interval [CI] 1.39-2.63, p < 0.001). Established risk factors including parity (AOR 0.45, CI 0.30-0.69, p < 0.001 for multipara versus paucipara) and age (AOR, CI and p-value for women aged 13–17, 18–22, 23–27 and ≥28 years, respectively: AOR 0.59, CI 0.40-0.88; AOR 0.57, CI 0.34-0.97; AOR 0.51, CI 0.29-0.91) were significant risk factors for P. falciparum infection. High-risk groups including nulli- and primipara and younger women aged 13–17 years showed a disproportionately increased risk for malaria in high transmission seasons from 17% to 64% prevalence in low and high transmission periods, respectively. Conclusion Seasonal variations lead to important differences in the risk for P. falciparum infection in pregnancy

  10. Preliminary cross section of Englebright Lake sediments

    USGS Publications Warehouse

    Snyder, Noah P.; Hampton, Margaret A.

    2003-01-01

    Overview -- The Upper Yuba River Studies Program is a CALFED-funded, multidisciplinary investigation of the feasibility of introducing anadromous fish species to the Yuba River system upstream of Englebright Dam. Englebright Lake (Figure 1 on poster) is a narrow, 14-km-long reservoir located in the northern Sierra Nevada, northeast of Marysville, CA. The dam was completed in 1941 for the primary purpose of trapping sediment derived from mining operations in the Yuba River watershed. Possible management scenarios include lowering or removing Englebright Dam, which could cause the release of stored sediments and associated contaminants, such as mercury used extensively in 19th-century hydraulic gold mining. Transport of released sediment to downstream areas could increase existing problems including flooding and mercury bioaccumulation in sport fish. To characterize the extent, grain size, and chemistry of this sediment, a coring campaign was done in Englebright Lake in May and June 2002. More than twenty holes were drilled at 7 different locations along the longitudinal axis of the reservoir (Figure 4 on poster), recovering 6 complete sequences of post-reservoir deposition and progradation. Here, a longitudinal cross section of Englebright Lake is presented (Figure 5 on poster), including pre-dam and present-day topographic profiles, and sedimentologic sections for each coring site. This figure shows the deltaic form of the reservoir deposit, with a thick upper section consisting of sand and gravel overlying silt, a steep front, and a thinner lower section dominated by silt. The methodologies used to create the reservoir cross section are discussed in the lower part of this poster.

  11. Evaluation of oral health attitude and behavior among a group of dental students in Puducherry, India: A preliminary cross-sectional study

    PubMed Central

    Muthu, Jananni; Priyadarshini, Gayathri; Muthanandam, Sivaramakrishnan; Ravichndran, Saravanakumar; Balu, Pratebha

    2015-01-01

    Context: Oral behavior reflects individual perception on oral health. Behavior and attitude of oral health providers, especially dentists, towards oral health affect their capacity to deliver oral health care services. This attitude plays a important role in determining the oral health condition of population. Aim: The purpose of this study is to evaluate the oral health attitude and behavior among a group of dental students in India and to find any gender-based differences in terms of oral health attitude and behavior. Materials and Methods: A total of 282 dental students of Indira Gandhi Institute of Dental Sciences, SBV University, Puducherry, India participated in the study. A simplified English version of Hiroshima University Dental-Behavioral Inventory (HU-DBI) was adopted. Statistical Analysis Used: SSP version 2.80 software was used to analyze the data. Chi-square test was used to find the differences in the distribution of “yes” among students from the different academic year as well as between male and female students. Statistical significance was set at P ≤ 0.05. Results: Statistical significance was observed for the responses between the students from different academic years brushing frequency, careful brushing of teeth, using brush with hard bristles, careful self-evaluation of brushing and satisfied appearance of teeth and gums. Male students preferred to use a tooth brush with hard bristles and regular mouth washes than female students. With regards to worrying about bad breath, male students had more “yes” responses than females. Conclusions: Oral health attitude and behavior increased with the increasing levels of dental education, and no significant differences were observed among male and female dental students. PMID:26941521

  12. Averaging cross section data so we can fit it

    SciTech Connect

    Brown, D.

    2014-10-23

    The 56Fe cross section we are interested in have a lot of fluctuations. We would like to fit the average of the cross section with cross sections calculated within EMPIRE. EMPIRE is a Hauser-Feshbach theory based nuclear reaction code, requires cross sections to be smoothed using a Lorentzian profile. The plan is to fit EMPIRE to these cross sections in the fast region (say above 500 keV).

  13. Identity development, intelligence structure, and interests: a cross-sectional study in a group of Italian adolescents during the decision-making process

    PubMed Central

    Pellerone, Monica; Passanisi, Alessia; Bellomo, Mario Filippo Paolo

    2015-01-01

    Background Forming one’s identity is thought to be the key developmental task of adolescence, but profound changes in personality traits also occur in this period. The negotiation of complex social settings, the creation of an integrated identity, and career choice are major tasks of adolescence. The adolescent, having to make choices for his or her future, has not only to consider his or her own aspirations and interests but also to possess a capacity for exploration and commitment; in fact, career commitments can be considered as a fit between the study or career that is chosen and personal values, skills, and preferences. Methods The objective of the study reported here was to investigate the role of identity on profile of interests; the relation between identity and decisional style; the correlation between identity, aptitudes, interests, and school performance; and the predictive variables to school success. The research involved 417 Italian students who live in Enna, a small city located in Sicily, Italy, aged 16–19 years (197 males and 220 females) in the fourth year (mean =17.2, standard deviation =0.52) and the fifth year (mean =18.2, standard deviation =0.64) of senior secondary school. The research lasted for one school year; the general group of participants consisted of 470 students, and although all participants agreed to be part of the research, there was a dropout rate of 11.28%. They completed the Ego Identity Process Questionnaire to measure their identity development, the Intelligence Structure Test to investigate aptitudes, the Self-Directed Search to value interests, and General Decision Making Style questionnaire to describe their individual decisional style. Results The data showed that high-school performance was positively associated with rational decision-making style and identity diffusion predicted the use of avoidant style. Interests were related to identity exploration; the differentiation of preferences was related to identity

  14. The calculation of radar cross sections

    NASA Astrophysics Data System (ADS)

    Pizer, R.

    1980-04-01

    The FORTRAN program CHAOS, used for calculating cross sections is described including the physical approximations used to simplify Maxwell's equations. The scattering bodies are extended to both open and closed surfaces. The numerical methods used are supplied. The problems of wire junctions, of finite conductivity and the attaching of lumped loads to the structure are considered. Techniques for dealing with bodies having rotational or left-right symmetries are examined as well as the sparse matrix approximation and the complex frequency version of CHAOS. The formula used to calculate the impedance matrix elements, and the conventions adopted concerning coordinate systems and polarization are included.

  15. Correlation cross sections along the international border

    SciTech Connect

    Martiniuk, C.D. ); Le Fever, J.A.; Anderson, S.B. )

    1991-06-01

    The Manitoba-North Dakota (Canada-US) stratigraphic correlation project is a joint study between the Petroleum Branch of Manitoba Energy and Mines and the North Dakota Geological Survey. It is an attempt to correlate the differing stratigraphic terminologies established in the two jurisdictions by providing a reference cross section across the international boundary. The study involves the subsurface correlation of logs of the Paleozoic and Mesozoic sequences in the Manitoba and North Dakota portions of the Williston basin. The Paleozoic and Mesozoic sequences are subdivided for presentation into the following stratigraphic intervals: (a) Cambrian-Ordovician-Silurian, (b) Devonian, (c) Mississippian, (d) Jurassic, and (e) Cretaceous. Wireline logs show the actual stratigraphic correlations. A nomenclature chart is also presented from each sequence. In addition, the sections include a generalized description of lithologies, thicknesses, environments of deposition, and petroleum potential for each geographic area.

  16. Windowed multipole for cross section Doppler broadening

    NASA Astrophysics Data System (ADS)

    Josey, C.; Ducru, P.; Forget, B.; Smith, K.

    2016-02-01

    This paper presents an in-depth analysis on the accuracy and performance of the windowed multipole Doppler broadening method. The basic theory behind cross section data is described, along with the basic multipole formalism followed by the approximations leading to windowed multipole method and the algorithm used to efficiently evaluate Doppler broadened cross sections. The method is tested by simulating the BEAVRS benchmark with a windowed multipole library composed of 70 nuclides. Accuracy of the method is demonstrated on a single assembly case where total neutron production rates and 238U capture rates compare within 0.1% to ACE format files at the same temperature. With regards to performance, clock cycle counts and cache misses were measured for single temperature ACE table lookup and for windowed multipole. The windowed multipole method was found to require 39.6% more clock cycles to evaluate, translating to a 7.9% performance loss overall. However, the algorithm has significantly better last-level cache performance, with 3 fewer misses per evaluation, or a 65% reduction in last-level misses. This is due to the small memory footprint of the windowed multipole method and better memory access pattern of the algorithm.

  17. Actinide Targets for Neutron Cross Section Measurements

    SciTech Connect

    John D. Baker; Christopher A. McGrath

    2006-10-01

    The Advanced Fuel Cycle Initiative (AFCI) and the Generation IV Reactor Initiative have demonstrated a lack of detailed neutron cross-sections for certain "minor" actinides, those other than the most common (235U, 238U, and 239Pu). For some closed-fuel-cycle reactor designs more than 50% of reactivity will, at some point, be derived from "minor" actinides that currently have poorly known or in some cases not measured (n,?) and (n,f) cross sections. A program of measurements under AFCI has begun to correct this. One of the initial hurdles has been to produce well-characterized, highly isotopically enriched, and chemically pure actinide targets on thin backings. Using a combination of resurrected techniques and new developments, we have made a series of targets including highly enriched 239Pu, 240Pu, and 242Pu. Thus far, we have electrodeposited these actinide targets. In the future, we plan to study reductive distillation to achieve homogeneous, adherent targets on thin metal foils and polymer backings. As we move forward, separated isotopes become scarcer, and safety concerns become greater. The chemical purification and electodeposition techniques will be described.

  18. Neutronic Cross Section Calculations on Fluorine Nucleus

    NASA Astrophysics Data System (ADS)

    Kara, A.; Tel, E.

    2013-06-01

    Certain light nuclei such as Lithium (Li), Beryllium (Be), Fluorine (F) (which are known as FLİBE) and its molten salt compounds (LiF, BeF2 and NaF) can serve as a coolant which can be used at high temperatures without reaching a high vapor pressure. These molten salt compounds are also a good neutron moderator. In this study, cross sections of neutron induced reactions have been calculated for fluorine target nucleus. The new calculations on the excitation functions of 19F( n, 2n), 19F( n, p), 19F( n, xn), 19F( n, xp) have been made. In these calculations, the pre-equilibrium and equilibrium effects have been investigated. The pre-equilibrium calculations involve the full exciton model and the cascade exciton model. The equilibrium effects are calculated according to the Weisskopf-Ewing model. Also in the present work, the ( n, 2n) and ( n, p) reaction cross sections have calculated by using evaluated empirical formulas developed by Tel et al. at 14-15 MeV energy. The multiple pre-equilibrium mean free path constant from internal transition have been investigated for 19F nucleus. The obtained results have been discussed and compared with the available experimental data.

  19. Accurate universal parameterization of absorption cross sections II--neutron absorption cross sections

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.

    1997-01-01

    A recent parameterization (here after referred as paper I, Ref. [4]) of absorption cross sections for any system of charged ions collisions including proton -nucleus collisions, is extended for neutron-nucleus collisions valid from approximately 1 MeV to a few GeV, thus providing a comprehensive picture of absorption cross sections for any system of collision pair (charged and/or uncharged). The parameters are associated with the physics of the problem. At lower energies, the optical potential at the surface is important and the Pauli operator plays an increasingly important role at intermediate energies. The agreement between the calculated and experimental data is better than earlier published results.

  20. FTR Set 500: a multigroup cross-section set for FTR analysis

    SciTech Connect

    Mann, F M

    1982-02-01

    FTR Set 500 is a 53-neutron-group, 20-photon-group, cross-section set based on ENDF/B-V cross sections and neutron spectra typical of the Fast Test Reactor (FTR). This report describes the specifications and processing of Set 500 and provides one-group values of this set for use in limited FTR analyses.

  1. Photofission cross section of /sup 232/Th

    SciTech Connect

    Zhang, H.X.; Yeh, T.R.; Lancman, H.

    1986-10-01

    The photofission cross section of /sup 232/Th was measured in the 5.8-12 MeV energy range with an average photon energy resolution of 600 eV. Intermediate structure was observed at 5.91, 5.97, and 6.31 MeV. The experimental fission probability and various properties of the intermediate structure were compared with calculated values based on a double-humped fission barrier as well as a triple-humped one. The results favor, though not decisively, the presence of a shallow third well in the barrier. Certain features of both barriers, a rather high first hump and a deep secondary well, are quite different from those predicted by current theoretical barrier calculations.

  2. Lunar Radar Cross Section at Low Frequency

    NASA Technical Reports Server (NTRS)

    Rodriguez, P.; Kennedy, E. J.; Kossey, P.; McCarrick, M.; Kaiser, M. L.; Bougeret, J.-L.; Tokarev, Y. V.

    2002-01-01

    Recent bistatic measurements of the lunar radar cross-section have extended the spectrum to long radio wavelength. We have utilized the HF Active Auroral Research Program (HAARP) radar facility near Gakona, Alaska to transmit high power pulses at 8.075 MHz to the Moon; the echo pulses were received onboard the NASA/WIND spacecraft by the WAVES HF receiver. This lunar radar experiment follows our previous use of earth-based HF radar with satellites to conduct space experiments. The spacecraft was approaching the Moon for a scheduled orbit perturbation when our experiment of 13 September 2001 was conducted. During the two-hour experiment, the radial distance of the satellite from the Moon varied from 28 to 24 Rm, where Rm is in lunar radii.

  3. Top cross section measurement at CDF

    SciTech Connect

    Compostella, Gabriele; /INFN, CNAF /Padua U.

    2010-01-01

    This paper describes the latest measurements of the t{bar t} pair production cross section performed by the CDF Collaboration analyzing p{bar p} collisions at a center-of-mass energy of 1.96 TeV from Fermilab Tevatron, as presented at the XVIII International Workshop on Deep-Inelastic Scattering and Related Subjects. In order to test Standard Model predictions, several analysis methods are explored and all the top decay channels are considered, to better constrain the properties of the top quark and to search for possible sources of new physics affecting the pair production mechanism. Experimental results using an integrated luminosity up to 5.1 fb{sup -1} are presented.

  4. Absolute photoneutron cross sections of Sm isotopes

    SciTech Connect

    Gheorghe, I.; Glodariu, T.; Utsunomiya, H.; Filipescu, D.; Nyhus, H.-T.; Renstrom, T.; Tesileanu, O.; Shima, T.; Takahisa, K.; Miyamoto, S.

    2015-02-24

    Photoneutron cross sections for seven samarium isotopes, {sup 144}Sm, {sup 147}Sm, {sup 148}Sm, {sup 149}Sm, {sup 150}Sm, {sup 152}Sm and {sup 154}Sm, have been investigated near neutron emission threshold using quasimonochromatic laser-Compton scattering γ-rays produced at the synchrotron radiation facility NewSUBARU. The results are important for nuclear astrophysics calculations and also for probing γ-ray strength functions in the vicinity of neutron threshold. Here we describe the neutron detection system and we discuss the related data analysis and the necessary method improvements for adapting the current experimental method to the working parameters of the future Gamma Beam System of Extreme Light Infrastructure - Nuclear Physics facility.

  5. Geophysical Fluid Flow Cell (GFFC) Cross Section

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This drawing shows a cross-section view of the test cell at the heart of the Geophysical Fluid Flow Cell (GFFC) that flew on two Spacelab missions. The middle and lower drawings depict the volume of the silicone oil layer that served as the atmosphere as the steel ball rotated and an electrostatic field pulled the oil inward to mimic gravity's effects during the experiments. The GFFC thus produced flow patterns that simulated conditions inside the atmospheres of Jupiter and the Sun and other stars. The principal investigator was John Hart of the University of Colorado at Boulder. It was managed by NASA's Marshall Space Flight Center (MSFC). An Acrobat PDF copy of this drawing is available at http://microgravity.nasa.gov/gallery. (Credit: NASA/Marshall Space Flight Center)

  6. Collision cross sections for structural proteomics.

    PubMed

    Marklund, Erik G; Degiacomi, Matteo T; Robinson, Carol V; Baldwin, Andrew J; Benesch, Justin L P

    2015-04-01

    Ion mobility mass spectrometry (IM-MS) allows the structural interrogation of biomolecules by reporting their collision cross sections (CCSs). The major bottleneck for exploiting IM-MS in structural proteomics lies in the lack of speed at which structures and models can be related to experimental data. Here we present IMPACT (Ion Mobility Projection Approximation Calculation Tool), which overcomes these twin challenges, providing accurate CCSs up to 10(6) times faster than alternative methods. This allows us to assess the CCS space presented by the entire structural proteome, interrogate ensembles of protein conformers, and monitor molecular dynamics trajectories. Our data demonstrate that the CCS is a highly informative parameter and that IM-MS is of considerable practical value to structural biologists. PMID:25800554

  7. New Fission Cross Section Measurements using a Time Projection Chamber

    NASA Astrophysics Data System (ADS)

    Sadler, Michael

    2008-03-01

    A group of six universities (ACU, California Polytechnic, Colorado School of Mines, Georgia Institute of Technology, Ohio, and Oregon State) and three national laboratories (Los Alamos, Lawrence Livermore, and Idaho) have undertaken the task of building a Time Projection Chamber (TPC) to measure the fission cross sections needed for the next generation of nuclear reactors. The fission TPC concept will be presented, and why we think we can improve on 50 years of fission study.

  8. Experiments on Antiprotons: Antiproton-Nucleon Cross Sections

    DOE R&D Accomplishments Database

    Chamberlain, Owen; Keller, Donald V.; Mermond, Ronald; Segre, Emilio; Steiner, Herbert M.; Ypsilantis, Tom

    1957-07-22

    In this paper experiments are reported on annihilation and scattering of antiprotons in H{sub 2}O , D{sub 2}O, and O{sub 2}. From the data measured it is possible to obtain an antiproton-proton and an antiproton-deuteron cross section at 457 Mev (lab). Further analysis gives the p-p and p-n cross sections as 104 mb for the p-p reaction cross section and 113 mb for the p-n reaction cross section. The respective annihilation cross sections are 89 and 74 mb. The Glauber correction necessary in order to pass from the p-d to the p-n cross section by subtraction of the p-p cross section is unfortunately large and somewhat uncertain. The data are compared with the p-p and p-n cross sections and with other results on p-p collisions.

  9. Single-level resonance parameters fit nuclear cross-sections

    NASA Technical Reports Server (NTRS)

    Drawbaugh, D. W.; Gibson, G.; Miller, M.; Page, S. L.

    1970-01-01

    Least squares analyses of experimental differential cross-section data for the U-235 nucleus have yielded single level Breit-Wigner resonance parameters that fit, simultaneously, three nuclear cross sections of capture, fission, and total.

  10. Electron Elastic-Scattering Cross-Section Database

    National Institute of Standards and Technology Data Gateway

    SRD 64 NIST Electron Elastic-Scattering Cross-Section Database (PC database, no charge)   This database provides values of differential elastic-scattering cross sections, corresponding total elastic-scattering cross sections, phase shifts, and transport cross sections for elements with atomic numbers from 1 to 96 and for electron energies between 50 eV and 20,000 eV (in steps of 1 eV).

  11. Electron cross section set for CHF{sub 3}

    SciTech Connect

    Morgan, W. Lowell; Winstead, Carl; McKoy, Vincent

    2001-08-15

    We describe the development of a consistent set of low-energy electron collision cross sections for trifluoromethane, CHF{sub 3}. First-principles calculations are used to obtain key elastic and inelastic cross sections. These are combined with literature values of the ionization cross section and with vibrational excitation cross sections obtained from the Born approximation to form a preliminary set, which is then adjusted to achieve consistency with measured swarm parameters. {copyright} 2001 American Institute of Physics.

  12. Mental Visualization of Objects from Cross-Sectional Images

    ERIC Educational Resources Information Center

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2012-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object…

  13. A simple approach to SEU cross section evaluation

    SciTech Connect

    Miroshkin, V.V.; Tverskoy, M.G.

    1998-12-01

    The simplified method for determination of proton induced SEU cross section is presented. The method is based on results of the analysis of experimental SEU cross sections initiated by fast nucleons. The possibility of SEU cross section measurement at single proton energy for SEU rate prediction is shown.

  14. Viscous Flow through Pipes of Various Cross-Sections

    ERIC Educational Resources Information Center

    Lekner, John

    2007-01-01

    An interesting variety of pipe cross-sectional shapes can be generated, for which the Navier-Stokes equations can be solved exactly. The simplest cases include the known solutions for elliptical and equilateral triangle cross-sections. Students can find pipe cross-sections from solutions of Laplace's equation in two dimensions, and then plot the…

  15. Normalization of experimental electron cross sections.

    NASA Astrophysics Data System (ADS)

    Avdonina, N.; Felfli, Z.; Msezane, A. Z.

    1997-10-01

    Absolute experimental electron-impact differential cross sections (DCSs) can be obtained through an extrapolation of the relative generalized oscillator strength (GOS) values at some given impact energy E to zero momentum transfer squared K^2, the optical oscillator strength (OOS) [1]. We propose to normalize the relative experimental DCS data to the corresponding OOS value by extrapolating the GOS to K^2 = 0 without involving the nonphysical region. This is possible only by simultaneously increasing E and decreasing K^2 so that K^2 = 0 corresponds to E = ∞. Thus is avoided a divergence of fracd(GOS)d(K^2) at K^2 = 0 [2]. Another advantage of our method is that, over a wide range of small K^2 values the contribution of higher order terms of the Born series to the GOS function is negligible, contrary to the constant E case in which even order K^2 terms are non-Born [2]. Thus first Born approximation can be used to normalize relative experimental DCSs to the OOS. This method is applicable to both the excitation and ionization of atomic and molecular targets by electron impact. The latter case generalizes the method of ref. [3]. ^*Supported by AFOSR, NSF and DoE Div. of Chemical Sciences, OBES. ^1 E. N. Lassettre et al., J. Chem. Phys \\underline50, (1829) ^2 W. M. Huo, J. Chem. Phys \\underline71, 1593 (1979) ^3 A. Saenz, W Weyrich and P. Froelich, J. Phys. B \\underline29, 97 (1996)

  16. APPARATUS FOR MEASURING TOTAL NEUTRON CROSS SECTIONS

    DOEpatents

    Cranberg, L.

    1959-10-13

    An apparatus is described for measuring high-resolution total neutron cross sections at high counting rate in the range above 50-kev neutron energy. The pulsed-beam time-of-flight technique is used to identify the neutrons of interest which are produced in the target of an electrostatic accelerator. Energy modulation of the accelerator . makes it possible to make observations at 100 energy points simultaneously. 761O An apparatus is described for monitoring the proton resonance of a liquid which is particulariy useful in the continuous purity analysis of heavy water. A hollow shell with parallel sides defines a meander chamber positioned within a uniform magnetic fieid. The liquid passes through an inlet at the outer edge of the chamber and through a spiral channel to the central region of the chamber where an outlet tube extends into the chamber perpendicular to the magnetic field. The radiofrequency energy for the monitor is coupled to a coil positioned coaxially with the outlet tube at its entrance point within the chamber. The improvement lies in the compact mechanical arrangement of the monitor unit whereby the liquid under analysis is subjected to the same magnetic field in the storage and sensing areas, and the entire unit is shielded from external electrostatic influences.

  17. [Fast neutron cross section measurements]. Progress report

    SciTech Connect

    Knoll, G.F.

    1992-10-26

    From its inception, the Nuclear Data Project at the University of Michigan has concentrated on two major objectives: (1) to carry out carefully controlled nuclear measurements of the highest possible reliability in support of the national nuclear data program, and (2) to provide an educational opportunity for students with interests in experimental nuclear science. The project has undergone a successful transition from a primary dependence on our photoneutron laboratory to one in which our current research is entirely based on a unique pulsed 14 MeV fast neutron facility. The new experimental facility is unique in its ability to provide nanosecond bursts of 14 MeV neutrons under conditions that are ``clean`` and as scatter-free as possible, and is the only one of its type currently in operation in the United States. It has been designed and put into operation primarily by graduate students, and has met or exceeded all of its important initial performance goals. We have reached the point of its routine operation, and most of the data are now in hand that will serve as the basis for the first two doctoral dissertations to be written by participating graduate students. Our initial results on double differential neutron cross sections will be presented at the May 1993 Fusion Reactor Technology Workshop. We are pleased to report that, after investing several years in equipment assembly and optimization, the project has now entered its ``data production`` phase.

  18. SCAMPI: A code package for cross-section processing

    SciTech Connect

    Parks, C.V.; Petrie, L.M.; Bowman, S.M.; Broadhead, B.L.; Greene, N.M.; White, J.E.

    1996-04-01

    The SCAMPI code package consists of a set of SCALE and AMPX modules that have been assembled to facilitate user needs for preparation of problem-specific, multigroup cross-section libraries. The function of each module contained in the SCANTI code package is discussed, along with illustrations of their use in practical analyses. Ideas are presented for future work that can enable one-step processing from a fine-group, problem-independent library to a broad-group, problem-specific library ready for a shielding analysis.

  19. Electron-impact-ionization cross section for the hydrogen atom

    NASA Astrophysics Data System (ADS)

    Hu, W.; Fang, D.; Wang, Y.; Yang, F.

    1994-02-01

    A distorted-wave Born exchange approximation was used to calculate the cross section for electron-impact ionization of the hydrogen atoms. Both the integral and energy-differential cross section were calculated. The results were compared with the latest experimental data and other theoretical calculations. Comparison shows that the calculations agree with differential cross-section measurements in general. For integral cross sections the calculation shows a better agreement with an earlier measurement [M.B. Shah, D. S. Elliott, and H. B. Gilbody, J. Phys. B 20, 3501 (1987)] in which the cross sections are normalized to the first Born approximation.

  20. Fast-neutron scattering cross sections of elemental silver

    SciTech Connect

    Smith, A.B.; Guenther, P.T.

    1982-05-01

    Differential neutron elastic- and inelastic-scattering cross sections of elemental silver are measured from 1.5 to 4.0 MeV at intervals of less than or equal to 200 keV and at 10 to 20 scattering angles distributed between 20 and 160/sup 0/. Inelastically-scattered neutron groups are observed corresponding to the excitation of levels at; 328 +- 13, 419 +- 50, 748 +- 25, 908 +- 26, 1150 +- 38, 1286 +- 25, 1507 +- 20, 1623 +- 30, 1835 +- 20 and 1944 +- 26 keV. The experimental results are used to derive an optical-statistical model that provides a good description of the observed cross sections. The measured values are compared with corresponding quantities given in ENDF/B-V.

  1. Quantifying and predicting interpretational uncertainty in cross-sections

    NASA Astrophysics Data System (ADS)

    Randle, Charles; Bond, Clare; Monaghan, Alison; Lark, Murray

    2015-04-01

    Cross-sections are often constructed from data to create a visual impression of the geologist's interpretation of the sub-surface geology. However as with all interpretations, this vision of the sub-surface geology is uncertain. We have designed and carried out an experiment with the aim of quantifying the uncertainty in geological cross-sections created by experts interpreting borehole data. By analysing different attributes of the data and interpretations we reflect on the main controls on uncertainty. A group of ten expert modellers at the British Geological Survey were asked to interpret an 11.4 km long cross-section from south-east Glasgow, UK. The data provided consisted of map and borehole data of the superficial deposits and shallow bedrock. Each modeller had a unique set of 11 boreholes removed from their dataset, to which their interpretations of the top of the bedrock were compared. This methodology allowed quantification of how far from the 'correct answer' each interpretation is at 11 points along each interpreted cross-section line; through comparison of the interpreted and actual bedrock elevations in the boreholes. This resulted in the collection of 110 measurements of the error to use in further analysis. To determine the potential control on uncertainty various attributes relating to the modeller, the interpretation and the data were recorded. Modellers were asked to fill out a questionnaire asking for information; such as how much 3D modelling experience they had, and how long it took them to complete the interpretation. They were also asked to record their confidence in their interpretations graphically, in the form of a confidence level drawn onto the cross-section. Initial analysis showed the majority of the experts' interpreted bedrock elevations within 5 metres of those recorded in the withheld boreholes. Their distribution is peaked and symmetrical about a mean of zero, indicating that there was no tendency for the experts to either under

  2. Hydraulic geometry of river cross sections; theory of minimum variance

    USGS Publications Warehouse

    Williams, Garnett P.

    1978-01-01

    This study deals with the rates at which mean velocity, mean depth, and water-surface width increase with water discharge at a cross section on an alluvial stream. Such relations often follow power laws, the exponents in which are called hydraulic exponents. The Langbein (1964) minimum-variance theory is examined in regard to its validity and its ability to predict observed hydraulic exponents. The variables used with the theory were velocity, depth, width, bed shear stress, friction factor, slope (energy gradient), and stream power. Slope is often constant, in which case only velocity, depth, width, shear and friction factor need be considered. The theory was tested against a wide range of field data from various geographic areas of the United States. The original theory was intended to produce only the average hydraulic exponents for a group of cross sections in a similar type of geologic or hydraulic environment. The theory does predict these average exponents with a reasonable degree of accuracy. An attempt to forecast the exponents at any selected cross section was moderately successful. Empirical equations are more accurate than the minimum variance, Gauckler-Manning, or Chezy methods. Predictions of the exponent of width are most reliable, the exponent of depth fair, and the exponent of mean velocity poor. (Woodard-USGS)

  3. Humeral cross-sectional shape in suspensory primates and sloths.

    PubMed

    Patel, Biren A; Ruff, Christopher B; Simons, Erin L R; Organ, Jason M

    2013-04-01

    Studies on the cross-sectional geometry of long bones in African apes have documented that shape ratios derived from second moments of area about principle axes (e.g., Imax /Imin ) are often correlated with habitual locomotor behaviors. For example, humeral cross-sections tend to appear more circular in more arboreal and forelimb suspensory chimpanzees compared with terrestrial quadrupedal gorillas. These data support the hypothesis that cross-sections that are more circular in shape are adapted for multidirectional loading regimes and bending moments encountered when using acrobatic locomotor behaviors. Whether a more circular humerus reflects greater use of forelimb suspension in other primates and nonprimate mammals is unknown. In this study, cross-sections at or near midshaft of the humerus were obtained from anthropoid primates that differ in their use of forelimb suspension, as well as from two genera of suspensory sloths. Imax /Imin ratios were compared within and between groups, and correlations were made with behavioral data. In broad comparisons, observed differences in morphology follow predicted patterns. Humeri of suspensory sloths are circular. Humeri of the more suspensory hominoids tend to be more circular than those of quadrupedal taxa. Humeri of the suspensory atelines are similar to hominoids, while those of Cebus are more like nonsuspensory cercopithecoids. There is, however, considerable overlap between taxa and within finer comparisons variation between species are not in the predicted direction. Thus, although Imax /Imin ratios of the humerus are informative for characterizing generalized locomotor modes (i.e., forelimb suspensory vs. quadrupedal), additional structural information is needed for more fine-grained assessments of locomotion. PMID:23408647

  4. Generation of Collapsed Cross Sections for Hatch 1 Cycles 1-3

    SciTech Connect

    Ade, Brian J

    2012-11-01

    Under NRC JCN V6361, Oak Ridge National Laboratory (ORNL) was tasked to develop and run SCALE/TRITON models for generation of collapsed few-group cross sections and to convert the cross sections to PMAXS format using the GENPMAXS conversion utility for use in PARCS/PATHS simulations of Hatch Unit 1, cycles 1-3. This letter report documents the final models used to produce the Hatch collapsed cross sections.

  5. Experimental verification of theoretical cross sections for FIB PIXE

    NASA Astrophysics Data System (ADS)

    Streib, Kenneth L.; Alford, Terry L.; Mayer, James W.

    2006-08-01

    X-ray production cross sections were found for films of Cr, Cu, Ge, Ag, W and Au, using incident H+ and Be+ ions at energies from 300 keV to 3.5 MeV. These experimental cross section results were compared with the cross section results obtained using software which calculates inner shell ionization and X-ray production cross sections. The software uses the ECPSSR-UA approach to finding X-ray production cross sections. This program was found to be useful for predicting cross sections for H+ and Be+ ions at the energies in this study. The software was then used to predict results for Li+, Be+ and B+ ions at 280 keV, energies available in the Arizona State University focused ion beam laboratory.

  6. Partial Photoneutron Cross Sections for 207,208Pb

    NASA Astrophysics Data System (ADS)

    Kondo, T.; Utsunomiya, H.; Goriely, S.; Iwamoto, C.; Akimune, H.; Yamagata, T.; Toyokawa, H.; Harada, H.; Kitatani, F.; Lui, Y.-W.; Hilaire, S.; Koning, A. J.

    2014-05-01

    Using linearly-polarized laser-Compton scattering γ-rays, partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near neutron threshold by measuring anisotropies in photoneutron emission. Separately, total photoneutron cross sections were measured for 207,208Pb with a high-efficiency 4π neutron detector. The partial cross section measurement provides direct evidence for the presence of pygmy dipole resonance (PDR) in 207,208Pb in the vicinity of neutron threshold. The strength of PDR amounts to 0.32%-0.42% of the Thomas-Reiche-Kuhn sum rule. Several μN2 units of B(M1)↑ strength were observed in 207,208Pb just above neutron threshold, which correspond to M1 cross sections less than 10% of the total photoneutron cross sections.

  7. Charge exchange cross sections for the Io plasma torus

    NASA Astrophysics Data System (ADS)

    McGrath, M. A.; Johnson, R. E.

    1989-03-01

    An impact parameter method for calculating cross sections as a function of incident ion energy is used in conjunction with an improved exchange energy formulation to update several of the charge exchange cross sections currently used in Io plasma torus modeling. New cross sections for S(+) + S(2+) yielding S(2+) + S(+) and Na(+) on neutral targets, useful in analyzing the fast Na jets observed at Io, are also calculated.

  8. Analytical formulation of the quantum electromagnetic cross section

    NASA Astrophysics Data System (ADS)

    Brandsema, Matthew J.; Narayanan, Ram M.; Lanzagorta, Marco

    2016-05-01

    It has been found that the quantum radar cross section (QRCS) equation can be written in terms of the Fourier transform of the surface atom distribution of the object. This paper uses this form to provide an analytical formulation of the quantum radar cross section by deriving closed form expressions for various geometries. These expressions are compared to the classical radar cross section (RCS) expressions and the quantum advantages are discerned from the differences in the equations. Multiphoton illumination is also briefly discussed.

  9. Projectile and Lab Frame Differential Cross Sections for Electromagnetic Dissociation

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Adamczyk, Anne; Dick, Frank

    2008-01-01

    Differential cross sections for electromagnetic dissociation in nuclear collisions are calculated for the first time. In order to be useful for three - dimensional transport codes, these cross sections have been calculated in both the projectile and lab frames. The formulas for these cross sections are such that they can be immediately used in space radiation transport codes. Only a limited amount of data exists, but the comparison between theory and experiment is good.

  10. Single event upset cross sections at various data rates

    SciTech Connect

    Reed, R.A.; Marshall, C.J.; McMorrow, D.; Carts, M.A.; Marshall, P.W.; Buchner, S.; La Macchia, M.; Mathes, B.

    1996-12-01

    The authors present data which show that Single Event Upset (SEU) cross section varies linearly with frequency for most devices tested. They show that the SEU cross section can increase dramatically away from a linear relationship when the test setup is not optimized, or when testing near the maximum operating frequency. They also observe non-linear behavior in some complex circuit topologies. Knowledge of the relationship between SEU cross section and frequency is important for estimates of on-orbit SEU rates.

  11. Measured microwave scattering cross sections of three meteorite specimens

    NASA Technical Reports Server (NTRS)

    Hughes, W. E.

    1972-01-01

    Three meteorite specimens were used in a microwave scattering experiment to determine the scattering cross sections of stony meteorites and iron meteorites in the frequency range from 10 to 14 GHz. The results indicate that the stony meteorites have a microwave scattering cross section that is 30 to 50 percent of their projected optical cross section. Measurements of the iron meteorite scattering were inconclusive because of specimen surface irregularities.

  12. High E{sub T} jet cross sections at CDF

    SciTech Connect

    Flaugher, B.; CDF Collaboration

    1996-08-01

    The inclusive jet cross section for {ital p}{ital {anti p}} collisions at {radical}s = 1.8 TeV as measured by the CDF collaboration will be presented. Preliminary CDF measurements of the {Sigma} E{sub T} cross section at {radical}s = 1.8 TeV and the central inclusive jet cross section at {radical}s = 0.630 TeV will also be shown.

  13. Positive Scattering Cross Sections using Constrained Least Squares

    SciTech Connect

    Dahl, J.A.; Ganapol, B.D.; Morel, J.E.

    1999-09-27

    A method which creates a positive Legendre expansion from truncated Legendre cross section libraries is presented. The cross section moments of order two and greater are modified by a constrained least squares algorithm, subject to the constraints that the zeroth and first moments remain constant, and that the standard discrete ordinate scattering matrix is positive. A method using the maximum entropy representation of the cross section which reduces the error of these modified moments is also presented. These methods are implemented in PARTISN, and numerical results from a transport calculation using highly anisotropic scattering cross sections with the exponential discontinuous spatial scheme is presented.

  14. Neutron-capture Cross Sections from Indirect Measurements

    SciTech Connect

    Escher, J E; Burke, J T; Dietrich, F S; Ressler, J J; Scielzo, N D; Thompson, I J

    2011-10-18

    Cross sections for compound-nuclear reactions play an important role in models of astrophysical environments and simulations of the nuclear fuel cycle. Providing reliable cross section data remains a formidable task, and direct measurements have to be complemented by theoretical predictions and indirect methods. The surrogate nuclear reactions method provides an indirect approach for determining cross sections for reactions on unstable isotopes, which are difficult or impossible to measure otherwise. Current implementations of the method provide useful cross sections for (n,f) reactions, but need to be improved upon for applications to capture reactions.

  15. Documentation of Uncertainties in Experimental Cross Sections for EXFOR

    SciTech Connect

    Otuka, N.; Smith, D.L.

    2014-06-15

    Documentation of uncertainties and covariances in experimental nuclear reaction cross sections has been assessed. Following consideration of the importance of covariances for nuclear data in various nuclear applications, and presentation of a simple numerical example to demonstrate this point, the minimum basic concepts (mean, covariance, standard derivation, partial uncertainties, micro- and macro-correlation coefficients) are introduced. A deterministic approach to propagating the covariances in primary measured parameters (e.g., counts) to the derived cross sections is discussed, using a neutron-induced activation cross section measurement as an example. Finally, various approaches to documentation (publication, compilation) of experimental cross sections to facilitate their use in future evaluations are mentioned.

  16. Electron-Impact Total Ionization Cross Sections of Hydrocarbon Ions

    PubMed Central

    Irikura, Karl K.; Kim, Yong-Ki; Ali, M. A.

    2002-01-01

    The Binary-Encounter-Bethe (BEB) model for electron-impact total ionization cross sections has been applied to CH2+, CH3+, CH4+, C2H2+, C2H4+, C2H6+ and H3O+. The cross sections for the hydrocarbon ions are needed for modeling cool plasmas in fusion devices. No experimental data are available for direct comparison. Molecular constants to generate total ionization cross sections at arbitrary incident electron energies using the BEB formula are presented. A recent experimental result on the ionization of H3O+ is found to be almost 1/20 of the present theory at the cross section peak.

  17. Derivation of reaction cross sections from experimental elastic backscattering probabilities

    NASA Astrophysics Data System (ADS)

    Sargsyan, V. V.; Adamian, G. G.; Antonenko, N. V.; Gomes, P. R. S.

    2013-10-01

    The relationship between the backward elastic scattering probabilities and the reaction cross sections is derived. This is a very simple and useful method to extract reaction cross sections for heavy-ion systems. We compare the results of our method with those that use the traditional full elastic scattering angular distributions for several systems at energies near and above the Coulomb barrier. From the calculated reaction and capture cross sections that use the present method, we derive the cross sections of other mechanisms for weak nearly spherical systems.

  18. DBCC Software as Database for Collisional Cross-Sections

    NASA Astrophysics Data System (ADS)

    Moroz, Daniel; Moroz, Paul

    2014-10-01

    Interactions of species, such as atoms, radicals, molecules, electrons, and photons, in plasmas used for materials processing could be very complex, and many of them could be described in terms of collisional cross-sections. Researchers involved in plasma simulations must select reasonable cross-sections for collisional processes for implementing them into their simulation codes to be able to correctly simulate plasmas. However, collisional cross-section data are difficult to obtain, and, for some collisional processes, the cross-sections are still not known. Data on collisional cross-sections can be obtained from numerous sources including numerical calculations, experiments, journal articles, conference proceedings, scientific reports, various universities' websites, national labs and centers specifically devoted to collecting data on cross-sections. The cross-sections data received from different sources could be partial, corresponding to limited energy ranges, or could even not be in agreement. The DBCC software package was designed to help researchers in collecting, comparing, and selecting cross-sections, some of which could be constructed from others or chosen as defaults. This is important as different researchers may place trust in different cross-sections or in different sources. We will discuss the details of DBCC and demonstrate how it works and why it is beneficial to researchers working on plasma simulations.

  19. A cross-sectional survey of experts’ opinions about the relative effectiveness of tobacco control strategies for the general population versus disadvantaged groups: what do we choose in the absence of evidence?

    PubMed Central

    2013-01-01

    Background There is a clear disparity in smoking rates according to social disadvantage. In the absence of sufficiently robust data regarding effective strategies for reducing smoking prevalence in disadvantaged populations, understanding the views of tobacco control experts can assist with funding decisions and research agendas. Methods A web-based cross-sectional survey was conducted with 192 respondents (response rate 65%) sampled from the Australian and New Zealand Tobacco Control Contacts list and a literature search. Respondents were asked to indicate whether a number of tobacco control strategies were perceived to be effective for each of: the general population; Aboriginal and Torres Strait Islander people; those with a low income; and people with a mental illness. Results A high proportion of respondents indicated that mass media and increased tobacco taxation (84% and 89% respectively) were effective for the general population. Significantly lower proportions reported these two strategies were effective for sub-populations, particularly Aboriginal and Torres Strait Islanders (58% and 63% respectively, p’s < .0001). Subsidised medication was the only strategy associated with a greater proportion of respondents perceiving it to be effective in disadvantaged sub-populations compared to the general population. Tailored quit programs and culturally relevant programs were nominated as additional effective strategies for disadvantaged populations. Conclusions Views about subsidised medications in particular, suggest the need for robust cost-effectiveness data relevant to disadvantaged groups to avoid wastage of scarce tobacco control resources. Strategies perceived to be effective for disadvantaged populations such as tailored or culturally relevant programs require rigorous evaluation so that potential adoption of these approaches is evidence-based. PMID:24314097

  20. Using a Cross Section to Train Veterinary Students To Visualize Anatomical Structures in Three Dimensions.

    ERIC Educational Resources Information Center

    Provo, Judy; Lamar, Carlton; Newby, Timothy

    2002-01-01

    Uses a cross section to enhance three-dimensional knowledge of the anatomy of a canine head. Involves (n=124) veterinary students dissecting the head and experimental groups also identifying structures on a cross section of the head. Reports a positive impact of this experience on participant students. (Contains 52 references.) (Author/YDS)

  1. Electron impact cross sections for surrogates of DNA sugar phosphate backbone

    NASA Astrophysics Data System (ADS)

    Bhowmik, Pooja; Joshipura, K. N.; Pandya, Siddharth

    2012-11-01

    Ionization and elastic cross sections by electron impact on H3PO4 and OP(OCH3)3 which are substitutes for the components of DNA phosphate group. We have employed the Complex Scattering Potential-ionization contribution (CSP-ic) formalism to calculate the cross sections in the energy range from ionization threshold to 2000 eV.

  2. Cross Sections for Inner-Shell Ionization by Electron Impact

    SciTech Connect

    Llovet, Xavier; Powell, Cedric J.; Salvat, Francesc; Jablonski, Aleksander

    2014-03-15

    An analysis is presented of measured and calculated cross sections for inner-shell ionization by electron impact. We describe the essentials of classical and semiclassical models and of quantum approximations for computing ionization cross sections. The emphasis is on the recent formulation of the distorted-wave Born approximation by Bote and Salvat [Phys. Rev. A 77, 042701 (2008)] that has been used to generate an extensive database of cross sections for the ionization of the K shell and the L and M subshells of all elements from hydrogen to einsteinium (Z = 1 to Z = 99) by electrons and positrons with kinetic energies up to 1 GeV. We describe a systematic method for evaluating cross sections for emission of x rays and Auger electrons based on atomic transition probabilities from the Evaluated Atomic Data Library of Perkins et al. [Lawrence Livermore National Laboratory, UCRL-ID-50400, 1991]. We made an extensive comparison of measured K-shell, L-subshell, and M-subshell ionization cross sections and of Lα x-ray production cross sections with the corresponding calculated cross sections. We identified elements for which there were at least three (for K shells) or two (for L and M subshells) mutually consistent sets of cross-section measurements and for which the cross sections varied with energy as expected by theory. The overall average root-mean-square deviation between the measured and calculated cross sections was 10.9% and the overall average deviation was −2.5%. This degree of agreement between measured and calculated ionization and x-ray production cross sections was considered to be very satisfactory given the difficulties of these measurements.

  3. Section Builder: A finite element tool for analysis and design of composite beam cross-sections

    NASA Astrophysics Data System (ADS)

    Chakravarty, Uttam Kumar

    SectionBuilder is an innovative finite element based tool, developed for analysis and design of composite beam cross-sections. The tool can handle the cross-sections with parametric shapes and arbitrary configurations. It can also handle arbitrary lay-ups for predefined beam cross-section geometries in a consistent manner. The material properties for each layer of the cross-section can be defined on the basis of the design requirements. This tool is capable of dealing with multi-cell composite cross-sections with arbitrary lay-ups. It has also the benefit of handling the variation of thickness of skin and D-spars for beams such as rotor blades. A typical cross-section is considered as a collection of interconnected walls. Walls with arbitrary lay-ups based on predefined geometries and material properties are generated first. The complex composite beam cross-sections are developed by connecting the walls using various types of connectors. These connectors are compatible with the walls, i.e., the thickness of the layers of the walls must match with those of the connectors at the place of connection. Cross-sections are often reinforced by core material for constructing realistic rotor blade cross-sections. The tool has the ability to integrate core materials into the cross-sections. A mapped mesh is considered for meshing parametric shapes, walls and various connectors, whereas a free mesh is considered for meshing the core materials. A new algorithm based on the Delaunay refinement algorithm is developed for creating the best possible free mesh for core materials. After meshing the cross-section, the tool determines the sectional properties using finite element analysis. This tool computes sectional properties including stiffness matrix, compliance matrix, mass matrix, and principal axes. A visualization environment is integrated with the tool for visualizing the stress and strain distributions over the cross-section.

  4. Determination of Electron Collision Cross Sections Set for Tetramethysilane

    NASA Astrophysics Data System (ADS)

    Bordage, Marie-Claude

    2007-12-01

    A swarm analysis technique based on the solution of the Boltzmann equation is used to derive low energy electron collision cross sections for tetramethylsilane (TMS). The calculated swarm parameters with this first available cross sections set is consistent with measured values of the swarm parameters. Calculations of transport parameters in mixtures of TMS with argon are also presented.

  5. Temperature dependence of the HNO3 UV absorption cross sections

    NASA Technical Reports Server (NTRS)

    Burkholder, James B.; Talukdar, Ranajit K.; Ravishankara, A. R.; Solomon, Susan

    1993-01-01

    The temperature dependence of the HNO3 absorption cross sections between 240 and 360 K over the wavelength range 195 to 350 nm has been measured using a diode array spectrometer. Absorption cross sections were determined using both (1) absolute pressure measurements at 298 K and (2) a dual absorption cell arrangement in which the absorption spectrum at various temperatures is measured relative to the room temperature absorption spectrum. The HNO3 absorption spectrum showed a temperature dependence which is weak at short wavelengths but stronger at longer wavelengths which are important for photolysis in the lower stratosphere. The 298 K absorption cross sections were found to be larger than the values currently recommended for atmospheric modeling (DeMore et al., 1992). Our absorption cross section data are critically compared with the previous measurements of both room temperature and temperature-dependent absorption cross sections. Temperature-dependent absorption cross sections of HNO3 are recommended for use in atmospheric modeling. These temperature dependent HNO3 absorption cross sections were used in a two-dimensional dynamical-photochemical model to demonstrate the effects of the revised absorption cross sections on loss rate of HNO3 and the abundance of NO2 in the stratosphere.

  6. Benchmark Calculations of Electron-Impact Differential Cross Sections

    SciTech Connect

    Bray, I.; Bostock, C. J.; Fursa, D. V.; Hines, C. W.; Kadyrov, A. S.; Stelbovics, A. T.

    2011-05-11

    The calculation of electron-atom excitation and ionization cross section is considered in both the non-relativistic and relativistic scattering theory. We consider electron collisions with H, He, Cs, and Hg. Differential cross sections for elastic scattering and ionization are presented.

  7. Cross Sections for Electron Collisions with Carbon Monoxide

    SciTech Connect

    Itikawa, Yukikazu

    2015-03-15

    Cross section data are collected and reviewed for electron collisions with carbon monoxide. Collision processes included are total scattering, elastic scattering, momentum transfer, excitations of rotational, vibrational and electronic states, ionization, and dissociation. For each process, recommended values of the cross sections are presented, when possible. The literature has been surveyed through to the end of 2013.

  8. The energy dependence of the total charm cross section

    SciTech Connect

    Vogt, R

    2007-10-18

    We discuss the energy dependence of the total charm cross section and some of its theoretical uncertainties including the quark mass, scale choice and the parton densities. We compare the next-to-leading order calculation of the total cross section with results obtained using PYTHIA.

  9. Analysis of cross sections using various nuclear potential

    SciTech Connect

    Aziz, Azni Abdul; Kassim, Hasan Abu; Yusof, Norhasliza; Muhammad Zamrun, F.

    2014-05-02

    The relevant astrophysical reaction rates which are derived from the reaction cross sections are necessary input to the reaction network. In this work, we analyse several theoretical models of the nuclear potential which give better prediction of the cross sections for some selected reactions.

  10. Learning of Cross-Sectional Anatomy Using Clay Models

    ERIC Educational Resources Information Center

    Oh, Chang-Seok; Kim, Ji-Young; Choe, Yeon Hyeon

    2009-01-01

    We incorporated clay modeling into gross anatomy and neuro-anatomy courses to help students understand cross-sectional anatomy. By making clay models, cutting them and comparing cut surfaces to CT and MR images, students learned how cross-sectional two-dimensional images were created from three-dimensional structure of human organs. Most students…

  11. Temperature-dependent high resolution absorption cross sections of propane

    NASA Astrophysics Data System (ADS)

    Beale, Christopher A.; Hargreaves, Robert J.; Bernath, Peter F.

    2016-10-01

    High resolution (0.005 cm-1) absorption cross sections have been measured for pure propane (C3H8). These cross sections cover the 2550-3500 cm-1 region at five temperatures (from 296 to 700 K) and were measured using a Fourier transform spectrometer and a quartz cell heated by a tube furnace. Calibrations were made by comparison to the integrated cross sections of propane from the Pacific Northwest National Laboratory. These are the first high resolution absorption cross sections of propane for the 3 μm region at elevated temperatures. The cross sections provided may be used to monitor propane in combustion environments and in astronomical sources such as the auroral regions of Jupiter, brown dwarfs and exoplanets.

  12. Consistent set of electron cross sections for methane

    NASA Astrophysics Data System (ADS)

    Alves, L. L.; Guerra, V.; Pintassilgo, C. D.

    2013-09-01

    This contribution presents a complete consistent set of electron-impact cross sections for methane (CH4) , recently made available on the IST-LISBON database with the LXCat website. The set is based on the cross sections originally compiled and adjusted in and first used in. The elementary processes taken into account are elastic momentum-transfer, vibrational excitation of the (1,3) and (2,4) modes, total dissociation into neutrals, and ionization producing CH4+and CH3++ H. For the latter two processes we have adjusted the partial ionization cross section of Chatham et al. as to reproduce their measured total ionization. The new cross-section set is validated by comparing calculated and measured electron swarm parameters for E / N = 0.1-400 Td. A discussion of similarities and differences with sets of CH4 cross sections from other databases is also presented. Work partially supported by FCT (Pest-OE/SADG/LA0010/2011).

  13. Temperature-dependent absorption cross sections for hydrogen peroxide vapor

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Wine, P. H.

    1988-01-01

    Relative absorption cross sections for hydrogen peroxide vapor were measured over the temperature ranges 285-381 K for lambda = 230 nm-295 nm and 300-381 K for lambda = 193 nm-350 nm. The well established 298 K cross sections at 202.6 and 228.8 nm were used as an absolute calibration. A significant temperature dependence was observed at the important tropospheric photolysis wavelengths lambda over 300 nm. Measured cross sections were extrapolated to lower temperatures, using a simple model which attributes the observed temperature dependence to enhanced absorption by molecules possessing one quantum of O-O stretch vibrational excitation. Upper tropospheric photodissociation rates calculated using the extrapolated cross sections are about 25 percent lower than those calculated using currently recommended 298 K cross sections.

  14. Fission cross section measurements of actinides at LANSCE

    SciTech Connect

    Tovesson, Fredrik; Laptev, Alexander B; Hill, Tony S

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications. By combining measurement at two LANSCE facilities, Lujan Center and the Weapons Neutron Research center (WNR), differential cross sections can be measured from sub-thermal energies up to 200 MeV. Incident neutron energies are determined using the time-of-flight method, and parallel-plate ionization chambers are used to measure fission cross sections relative to the {sup 235}U standard. Recent measurements include the {sup 233,238}U, {sup 239,242}Pu and {sup 243}Am neutron-induced fission cross sections. In this paper preliminary results for cross section data of {sup 243}Am and {sup 233}U will be presented.

  15. Spectral history correction of microscopic cross sections for the PBR using the slowing down balance

    SciTech Connect

    Hudson, N.; Rahnema, F.

    2006-07-01

    A method has been formulated to account for depletion effects on microscopic cross sections within a Pebble Bed Reactor (PBR) spectral zone without resorting to calls to the spectrum (cross section generation) code or relying upon table interpolation between data at different values of burnup. In this method, infinite medium microscopic cross sections, fine group fission spectra, and modulation factors are pre-computed at selected isotopic states. This fine group information is used with the local spectral zone nuclide densities to generate new cross sections for each spectral zone. The local spectrum used to generate these microscopic cross sections is estimated through the solution to the cell-homogenized, infinite medium slowing down balance equation during the flux calculation. This technique is known as Spectral History Correction (SHC), and it is formulated to specifically account for burnup within a spectral zone. It was found that the SHC technique accurately calculates local broad group microscopic cross sections with local burnup information. Good agreement is obtained with cross sections generated directly by the cross section generator. Encouraging results include improvement in the converged fuel cycle eigenvalue, the power peaking factor, and the flux. It was also found that the method compared favorably to the benchmark problem in terms of the computational speed. (authors)

  16. Electron impact rotationally elastic total cross section for formamide

    SciTech Connect

    Vinodkumar, Minaxi; Limbachiya, Chetan; Desai, Hardik Vinodkumar, P. C.

    2014-09-28

    This paper reports computational results of the total cross sections for electron impact on formamide (HCONH₂) over a wide range of energies from 0.01 eV to 5 keV. Total cross sections over such a wide range are reported for the first time as the earlier reported data is up to maximum of 12 eV. Below ionization threshold of the target, we performed ab initio calculations using UK molecular R-Matrix code within static, exchange plus polarization (SEP), and close coupling approximations. Twenty eight target states are included in close coupling formalism. Total 350 channels and 2410 configuration state functions are included in the calculations. We observe a π* shape resonance at 3.41 eV and a σ* resonance at 15.3 eV as against similar resonances reported at 3.77 eV and 14.9 eV, respectively, by Goumans et al. [J. Chem. Theory Comput. 5, 217 (2009)] using SEP model. The cross sections at higher energies are evaluated using the spherical complex optical potential formalism. The two methods are found to be consistent with a smooth cross over at 18 eV. The vertical excitation energies, electronic excitation cross sections, differential cross sections, momentum transfer, and total cross sections are computed. In absence of experimental data, we compared our computed total cross sections with available other theoretical results.

  17. Electron impact rotationally elastic total cross section for formamide

    NASA Astrophysics Data System (ADS)

    Vinodkumar, Minaxi; Limbachiya, Chetan; Desai, Hardik; Vinodkumar, P. C.

    2014-09-01

    This paper reports computational results of the total cross sections for electron impact on formamide (HCONH2) over a wide range of energies from 0.01 eV to 5 keV. Total cross sections over such a wide range are reported for the first time as the earlier reported data is up to maximum of 12 eV. Below ionization threshold of the target, we performed ab initio calculations using UK molecular R-Matrix code within static, exchange plus polarization (SEP), and close coupling approximations. Twenty eight target states are included in close coupling formalism. Total 350 channels and 2410 configuration state functions are included in the calculations. We observe a π* shape resonance at 3.41 eV and a σ* resonance at 15.3 eV as against similar resonances reported at 3.77 eV and 14.9 eV, respectively, by Goumans et al. [J. Chem. Theory Comput. 5, 217 (2009)] using SEP model. The cross sections at higher energies are evaluated using the spherical complex optical potential formalism. The two methods are found to be consistent with a smooth cross over at 18 eV. The vertical excitation energies, electronic excitation cross sections, differential cross sections, momentum transfer, and total cross sections are computed. In absence of experimental data, we compared our computed total cross sections with available other theoretical results.

  18. MOX Cross-Section Libraries for ORIGEN-ARP

    SciTech Connect

    Gauld, I.C.

    2003-07-01

    The use of mixed-oxide (MOX) fuel in commercial nuclear power reactors operated in Europe has expanded rapidly over the past decade. The predicted characteristics of MOX fuel such as the nuclide inventories, thermal power from decay heat, and radiation sources are required for design and safety evaluations, and can provide valuable information for non-destructive safeguards verification activities. This report describes the development of computational methods and cross-section libraries suitable for the analysis of irradiated MOX fuel with the widely-used and recognized ORIGEN-ARP isotope generation and depletion code of the SCALE (Standardized Computer Analyses for Licensing Evaluation) code system. The MOX libraries are designed to be used with the Automatic Rapid Processing (ARP) module of SCALE that interpolates appropriate values of the cross sections from a database of parameterized cross-section libraries to create a problem-dependent library for the burnup analysis. The methods in ORIGEN-ARP, originally designed for uranium-based fuels only, have been significantly upgraded to handle the larger number of interpolation parameters associated with MOX fuels. The new methods have been incorporated in a new version of the ARP code that can generate libraries for low-enriched uranium (LEU) and MOX fuel types. The MOX data libraries and interpolation algorithms in ORIGEN-ARP have been verified using a database of declared isotopic concentrations for 1042 European MOX fuel assemblies. The methods and data are validated using a numerical MOX fuel benchmark established by the Organization for Economic Cooperation and Development (OECD) Working Group on burnup credit and nuclide assay measurements for irradiated MOX fuel performed as part of the Belgonucleaire ARIANE International Program.

  19. Advanced Neutron Source Cross Section Libraries (ANSL-V): ENDF/B-V based multigroup cross-section libraries for advanced neutron source (ANS) reactor studies

    SciTech Connect

    Ford, W.E. III; Arwood, J.W.; Greene, N.M.; Moses, D.L.; Petrie, L.M.; Primm, R.T. III; Slater, C.O.; Westfall, R.M.; Wright, R.Q.

    1990-09-01

    Pseudo-problem-independent, multigroup cross-section libraries were generated to support Advanced Neutron Source (ANS) Reactor design studies. The ANS is a proposed reactor which would be fueled with highly enriched uranium and cooled with heavy water. The libraries, designated ANSL-V (Advanced Neutron Source Cross Section Libraries based on ENDF/B-V), are data bases in AMPX master format for subsequent generation of problem-dependent cross-sections for use with codes such as KENO, ANISN, XSDRNPM, VENTURE, DOT, DORT, TORT, and MORSE. Included in ANSL-V are 99-group and 39-group neutron, 39-neutron-group 44-gamma-ray-group secondary gamma-ray production (SGRP), 44-group gamma-ray interaction (GRI), and coupled, 39-neutron group 44-gamma-ray group (CNG) cross-section libraries. The neutron and SGRP libraries were generated primarily from ENDF/B-V data; the GRI library was generated from DLC-99/HUGO data, which is recognized as the ENDF/B-V photon interaction data. Modules from the AMPX and NJOY systems were used to process the multigroup data. Validity of selected data from the fine- and broad-group neutron libraries was satisfactorily tested in performance parameter calculations.

  20. The correction of pebble bed reactor nodal cross sections for the effects of leakage and depletion history

    NASA Astrophysics Data System (ADS)

    Hudson, Nathanael Harrison

    An accurate and computationally fast method to generate nodal cross sections for the Pebble Bed Reactor (PBR) was presented. In this method, named Spectral History Correction (SHC), a set of fine group microscopic cross section libraries, pre-computed at specified depletion and moderation states, was coupled with the nodal nuclide densities and group bucklings to compute the new fine group spectrum for each node. The relevant fine group cross-section library was then recollapsed to the local broad group cross-section structure with this new fine group spectrum. This library set was tracked in terms of fuel isotopic densities. Fine group modulation factors (to correct the homogeneous flux for heterogeneous effects) and fission spectra were also stored with the cross section library. As the PBR simulation converges to a steady state fuel cycle, the initial nodal cross section library becomes inaccurate due to the burnup of the fuel and the neutron leakage into and out of the node. Because of the recirculation of discharged fuel pebbles with fresh fuel pebbles, a node can consist of a collection of pebbles at various burnup stages. To account for the nodal burnup, the microscopic cross sections were combined with nodal averaged atom densities to approximate the fine group macroscopic cross-sections for that node. These constructed, homogeneous macroscopic cross sections within the node were used to calculate a numerical solution for the fine group spectrum with B1 theory. This new fine spectrum was used to collapse the pre-computed microscopic cross section library to the broad group structure employed by the fuel cycle code. This SHC technique was developed and practically implemented as a subroutine within the PBR fuel cycle code PEBBED. The SHC subroutine was called to recalculate the broad group cross sections during the code convergence. The result was a fast method that compared favorably to the benchmark scheme of cross section calculation with the lattice

  1. Cross Section Sensitivity and Propagated Errors in HZE Exposures

    NASA Technical Reports Server (NTRS)

    Heinbockel, John H.; Wilson, John W.; Blatnig, Steve R.; Qualls, Garry D.; Badavi, Francis F.; Cucinotta, Francis A.

    2005-01-01

    It has long been recognized that galactic cosmic rays are of such high energy that they tend to pass through available shielding materials resulting in exposure of astronauts and equipment within space vehicles and habitats. Any protection provided by shielding materials result not so much from stopping such particles but by changing their physical character in interaction with shielding material nuclei forming, hopefully, less dangerous species. Clearly, the fidelity of the nuclear cross-sections is essential to correct specification of shield design and sensitivity to cross-section error is important in guiding experimental validation of cross-section models and database. We examine the Boltzmann transport equation which is used to calculate dose equivalent during solar minimum, with units (cSv/yr), associated with various depths of shielding materials. The dose equivalent is a weighted sum of contributions from neutrons, protons, light ions, medium ions and heavy ions. We investigate the sensitivity of dose equivalent calculations due to errors in nuclear fragmentation cross-sections. We do this error analysis for all possible projectile-fragment combinations (14,365 such combinations) to estimate the sensitivity of the shielding calculations to errors in the nuclear fragmentation cross-sections. Numerical differentiation with respect to the cross-sections will be evaluated in a broad class of materials including polyethylene, aluminum and copper. We will identify the most important cross-sections for further experimental study and evaluate their impact on propagated errors in shielding estimates.

  2. Modeling elastic momentum transfer cross-sections from mobility data

    NASA Astrophysics Data System (ADS)

    Nikitović, Ž. D.; Stojanović, V. D.; Raspopović, Z. M.

    2016-04-01

    In this letter we present a new method to simply obtain the elastic momentum transfer cross-section which predicts a maximum of reduced mobility and its sensitivity to the temperature variation at low energies. We first determined the transport cross-section which resembles mobility data for similar closed-shell systems by using the Monte Carlo method. Second, we selected the most probable reactive processes and compiled cross-sections from experimental and theoretical data. At the end, an elastic momentum transfer cross-section is obtained by subtracting the compiled cross-sections from the momentum transfer cross-section, taking into account the effects of the angular scattering distributions. Finally, the cross-section set determined in such a way is used as an input in a final Monte Carlo code run, to calculate the flux and bulk reduced mobility for Ne+ + CF4 which were discussed as functions of the reduced electric field E/N (N is the gas density) for the temperature T = 300 K.

  3. Cross sections for electron scattering by atomic potassium

    SciTech Connect

    Msezane, A.Z.; Awuah, P.; Hiamang, S. Center for Theoretical Studies of Physical Systems, Clark Atlanta University, Atlanta, Georgia 30314 ); Allotey, F.K.A. )

    1992-12-01

    Electron elastic and collisional excitation cross sections from the ground state of potassium are calculated using the noniterative integral-equation method of Henry, Rountree, and Smith (Comput. Phys. Commun. 23, 233 (1981)) in the electron energy range 4{le}{ital E}{le}200 eV. Configuration-interaction target wave functions that take account of correlation and polarization effects are used to represent the ground state and the six lowest excited states 4{ital p} {sup 2}{ital P}{degree}, 5{ital s} {sup 2}{ital S}, 3{ital d} {sup 2}{ital D}, 5{ital p} {sup 2}{ital P}{degree}, 4{ital d} {sup 2}{ital D}, and 6{ital s} {sup 2}{ital S}. Elastic and discrete excitation cross sections are obtained in a seven-state close-coupling (7CC) approximation. The 7CC elastic and excitation cross sections are compared and contrasted. Near threshold the elastic cross section dominates the resonance, 4{ital s} {sup 2}{ital S}{r arrow}4{ital p} {sup 2}{ital P}{degree}, and the sum of the other remaining excitation cross sections. Comparison of our total cross sections with some available experimental and theoretical data is also effected. The discrepancy between the recent measurement of the total cross section by Kwan {ital et} {ital al}. (Phys. Rev. A 44, 1620 (1991)) on the one hand and other measurements near threshold on the other hand is explained.

  4. Cross-Sectional Drawing Techniques And The Artist

    NASA Astrophysics Data System (ADS)

    Berry, William A.

    1980-07-01

    Although Democritus, a Greek pholosopher of the fifth century B.C. described the use of cross-sections in analyzing a solid form, this method was not extensively developed in art until the Renaissance. The earliest treatise documenting the integration of the cross-section and linear perspective is Piero della Francesca's De prospective pingendi (c. 1480), in which a drawing of the human head is mathematically conceived and plotted by means of cross-section contours. Piero's method anticipates contemporary biostereometric techniques and current theories of visual perception. Outside of theoretical treatises the complete cross-section rarely occurs in art, though certain pictorial elements such as the religious halo can be interpreted as cross-sections. The chan-ging representation of the halo in art of the Medieval, Renaissance and Baroque periods parallels the development of the artist's concepts and techniques for representing form and space. During the Renaissance and Baroque periods the widespread use of contour hatching, a drawing technique based on the cross-section, indicates that the cross-section concept has played a greater role in pictorial representation than has generally been recognized.

  5. Review of electron impact excitation cross sections for copper atom

    SciTech Connect

    Winter, N.W.; Hazi, A.U.

    1982-02-01

    Excitation of atomic copper by electron impact plays an important role in the copper vapor laser and accurate cross sections are needed for understanding and modeling laser performance. During the past seven years, there have been several attempts to normalize the relative elastic and inelastic cross sections measured by Trajmar and coworkers. However, each of these efforts have yielded different cross sections, and the uncertainty in the correct normalization of the data has been a source of confusion and concern for the kinetic modeling efforts. This difficulty has motivated us to review previous work on the electron impact excitation of copper atom and to perform new calculations of the inelastic cross sections using the impact parameter method. In this memorandum we review the previous attempts to normalize the experimental data and provide a critical assessment of the accuracy of the resulting cross sections. We also present new theoretical cross sections for the electron impact excitation of the /sup 2/S ..-->.. /sup 2/P/sup 0/ and /sup 2/S ..-->.. /sup 2/D transitions in copper. When the experimental cross sections are renormalized to the results of the impact parameter calculations, they are a factor of three smaller than those published in the latest paper of Trajmar et. al. At impact energies above 60 eV the excitation cross sections obtained with the impact parameter method agree well with the results of the very recent, unpublished, close-coupling calculations of Henry. This agreement suggests that the present normalization of the experimental cross sections is probably the most reliable one obtained to date.

  6. Electron impact ionization cross sections of beryllium-tungsten clusters*

    NASA Astrophysics Data System (ADS)

    Sukuba, Ivan; Kaiser, Alexander; Huber, Stefan E.; Urban, Jan; Probst, Michael

    2016-01-01

    We report calculated electron impact ionization cross sections (EICSs) of beryllium-tungsten clusters, BenW with n = 1,...,12, from the ionization threshold to 10 keV using the Deutsch-Märk (DM) and the binary-encounter-Bethe (BEB) formalisms. The positions of the maxima of DM and BEB cross sections are mostly close to each other. The DM cross sections are more sensitive with respect to the cluster size. For the clusters smaller than Be4W they yield smaller cross sections than BEB and vice versa larger cross sections than BEB for clusters larger than Be6W. The maximum cross section values for the singlet-spin groundstate clusters range from 7.0 × 10-16 cm2 at 28 eV (BeW) to 54.2 × 10-16 cm2 at 43 eV (Be12W) for the DM cross sections and from 13.5 × 10-16 cm2 at 43 eV (BeW) to 38.9 × 10-16 cm2 at 43 eV (Be12W) for the BEB cross sections. Differences of the EICSs in different isomers and between singlet and triplet states are also explored. Both the DM and BEB cross sections could be fitted perfectly to a simple expression used in modeling and simulation codes in the framework of nuclear fusion research. Contribution to the Topical Issue "Atomic Cluster Collisions (7th International Symposium)", edited by Gerardo Delgado Barrio, Andrey Solov'Yov, Pablo Villarreal, Rita Prosmiti.Supplementary material in the form of one pdf file available from the Journal web page at http://dx.doi.org/10.1140/epjd/e2015-60583-7

  7. Relative charge transfer cross section from Rb (4d)

    NASA Astrophysics Data System (ADS)

    Shah, M. H.; Camp, H. A.; Trachy, M. L.; Fléchard, X.; Gearba, M. A.; Nguyen, H.; Brédy, R.; Lundeen, S. R.; Depaola, B. D.

    2005-08-01

    Relative charge transfer cross section measurements for the excited state Rb(4d) with 7keV Na+ is reported. The specific channels reported are Na++Rb(4d5/2)→Na(nl)+Rb+ , where the dominant transfer cross sections channels were nl=3d and 4s . Using a combination of a magneto-optical trap and recoil ion momentum spectroscopy (MOTRIMS methodology), the cross sections were measured relative to the previously studied Na++Rb(5s,5p) systems at the same collision energy.

  8. Relative charge transfer cross section from Rb(4d)

    SciTech Connect

    Shah, M.H.; Camp, H.A.; Trachy, M.L.; De Paola, B.D.; Flechard, X.; Gearba, M.A.; Nguyen, H.; Bredy, R.; Lundeen, S.R.

    2005-08-15

    Relative charge transfer cross section measurements for the excited state Rb(4d) with 7 keV Na{sup +} is reported. The specific channels reported are Na{sup +}+Rb(4d{sub 5/2}){yields}Na(nl)+Rb{sup +}, where the dominant transfer cross sections channels were nl=3d and 4s. Using a combination of a magneto-optical trap and recoil ion momentum spectroscopy (MOTRIMS methodology), the cross sections were measured relative to the previously studied Na{sup +}+Rb(5s,5p) systems at the same collision energy.

  9. Momentum transfer cross sections for the heavy noble gases

    NASA Astrophysics Data System (ADS)

    McEachran, R. P.; Stauffer, A. D.

    2014-06-01

    We present momentum transfer cross sections for elastic electron scattering from argon, krypton and xenon atoms over the energy range from zero to 1 keV. These have been calculated using the Dirac equations with a relativistic complex optical potential which includes polarization of the target atom by the incident electron and allows for the absorption of some of the incident electron flux into channels representing excitation and ionization of the atom. In order to aid in plasma modelling calculations, we provide simple analytic fits to these cross sections as well as to the elastic scattering cross sections. Comparisons are made with previous experimental and theoretical results.

  10. Actinide neutron-induced fission cross section measurements at LANSCE

    SciTech Connect

    Tovesson, Fredrik K; Laptev, Alexander B; Hill, Tony S

    2010-01-01

    Fission cross sections of a range of actinides have been measured at the Los Alamos Neutron Science Center (LANSCE) in support of nuclear energy applications in a wide energy range from sub-thermal energies up to 200 MeV. A parallel-plate ionization chamber are used to measure fission cross sections ratios relative to the {sup 235}U standard while incident neutron energies are determined using the time-of-flight method. Recent measurements include the {sup 233,238}U, {sup 239-242}Pu and {sup 243}Am neutron-induced fission cross sections. Obtained data are presented in comparison with ex isting evaluations and previous data.

  11. Cross sections for electron scattering from α-tetrahydrofurfuryl alcohol

    NASA Astrophysics Data System (ADS)

    Duque, H. V.; Chiari, L.; Jones, D. B.; Thorn, P. A.; Pettifer, Z.; da Silva, G. B.; Limão-Vieira, P.; Duflot, D.; Hubin-Franskin, M.-J.; Delwiche, J.; Blanco, F.; García, G.; Lopes, M. C. A.; Ratnavelu, K.; White, R. D.; Brunger, M. J.

    2014-07-01

    We report on measurements of integral cross sections (ICSs) for electron impact excitation of a series of Rydberg electronic-states in α-tetrahydrofurfuryl alcohol. The energy range of these experiments was 20-50 eV. There are currently no other results against which we can directly compare those measured data. We also report results from our independent atom model with screened additivity rule correction computations, namely for the total cross section, elastic ICS, inelastic ICS (all discrete electronic states and neutral dissociation) and the total ionisation ICS. Where possible, our calculated cross sections are compared to the limited available data of each scattering process.

  12. Fission cross sections in the intermediate energy region

    SciTech Connect

    Lisowski, P.W.; Gavron, A.; Parker, W.E.; Ullmann, J.L.; Balestrini, S.J. ); Carlson, A.D.; Wasson, O.A. ); Hill, N.W. )

    1991-01-01

    Until recently there has been very little cross section data for neutron-induced fission in the intermediate energy region, primarily because no suitable neutron source has existed. At Los Alamos, the WNR target-4 facility provides a high-intensity source of neutrons nearly ideal for fission measurements extending from a fraction of a MeV to several hundred MeV. This paper summarizes the status of fission cross section data in the intermediate energy range (En > 30 MeV) and presents our fission cross section data for {sup 235}U and {sup 238}U compared to intranuclear cascade and statistical model predictions.

  13. Cross-sectional study of health effects of cryolite production.

    PubMed

    Friis, H; Clausen, J; Gyntelberg, F

    1989-01-01

    A cross-sectional health study of 101 cryolite workers was performed, using spirometry and a questionnaire. Multiple regression analysis revealed a significant correlation between the index of smoking and a decrease in FEV1 (per cent). There was no significant correlation between work-related exposure and lung function. Many cryolite workers described a group of symptoms appearing after 15 to 30 min of heavy dust exposure: nausea, followed by epigastric pain with relief after spontaneous or provoked vomiting. Thirty-four (33.6 per cent) workers complained of nausea, vomiting or diarrhoea in relation to work, compared to 3.8 per cent of 1752 men participating in the Copenhagen Male Study. PMID:2622142

  14. Cross polarization caused by perturbed circular cross sections of waveguides and horn antennas

    NASA Astrophysics Data System (ADS)

    Lier, Erik

    1987-03-01

    The cross polarization caused by a perturbed cross section of the conical hybrid-mode horn is analyzed. The perturbed cross section is assumed to be slightly elliptical. The theory of Lier and Bergh (1986) for cross polarization in a smooth-walled waveguide supporting the TE11-mode is referred and applied to the HE11 mode as well. Simple analytical formulas which are sufficiently accurate for small ellipticites of the cross-section ellipse are presented. These show that the tolerances on the waveguide diameter are extremely strong, typically on the order of 0.02-0.04 mm in the horn throat for typical horn geometries at 12 GHz.

  15. Topological Optimization of Beam Cross Section by Employing Extrusion Constraint

    NASA Astrophysics Data System (ADS)

    Zuberi, Rehan H.; Zhengxing, Zuo; Kai, Long

    2010-05-01

    Optimal cross-section design of beams plays a characteristic role which signifies the rigidity of the member in bending, shear and torsion load conditions. Practically modern overhead crane girders, railway bridge girders or rail tracks etc. require constant cross-section along the axial direction. Conventional topological optimization modeling procedures in such cases prove inadequate for the reason that these procedures generate non-uniform topologies along the axis of the bending member. To examine optimal topology of those structural bending members which commonly possess constant cross-section along the axis the topology optimization with extrusion constraint is more appropriate. The extrusion constraint method suggests a fresh approach to investigate optimal topologies of beam cross-section under the influence of realistic loading condition across the section at the beginning of design cycle. Presented study is focused upon the influence of various configuration and location of the load and boundary conditions on the topology of the of the beam cross-section which was not possible prior to the materialization of the extrusion or stamping constraint method. Several realistic loads and boundary conditions have been applied on the 3D beam model and optimal cross-section topologies obtained have uniform compliance history and convergent solutions. The lowest compliance criteria have been suggested to choose topologies as furthers shape and size optimization candidates during beam design process.

  16. A genetic algorithm to reduce stream channel cross section data

    USGS Publications Warehouse

    Berenbrock, C.

    2006-01-01

    A genetic algorithm (GA) was used to reduce cross section data for a hypothetical example consisting of 41 data points and for 10 cross sections on the Kootenai River. The number of data points for the Kootenai River cross sections ranged from about 500 to more than 2,500. The GA was applied to reduce the number of data points to a manageable dataset because most models and other software require fewer than 100 data points for management, manipulation, and analysis. Results indicated that the program successfully reduced the data. Fitness values from the genetic algorithm were lower (better) than those in a previous study that used standard procedures of reducing the cross section data. On average, fitnesses were 29 percent lower, and several were about 50 percent lower. Results also showed that cross sections produced by the genetic algorithm were representative of the original section and that near-optimal results could be obtained in a single run, even for large problems. Other data also can be reduced in a method similar to that for cross section data.

  17. Differential cross sections of positron–hydrogen collisions

    NASA Astrophysics Data System (ADS)

    Rong-Mei, Yu; Chun-Ying, Pu; Xiao-Yu, Huang; Fu-Rong, Yin; Xu-Yan, Liu; Li-Guang, Jiao; Ya-Jun, Zhou

    2016-07-01

    We make a detailed study on the angular differential cross sections of positron–hydrogen collisions by using the momentum-space coupled-channels optical (CCO) method for incident energies below the H ionization threshold. The target continuum and the positronium (Ps) formation channels are included in the coupled-channels calculations via a complex equivalent-local optical potential. The critical points, which show minima in the differential cross sections, as a function of the scattering angle and the incident energy are investigated. The resonances in the angular differential cross sections are reported for the first time in this energy range. The effects of the target continuum and the Ps formation channels on the different cross sections are discussed. Project supported by the Nanyang Normal University Science Foundation of China (Grant No. ZX2013017) and the National Natural Science Foundation of China (Grant Nos. 11174066, 61306007, and U1304114).

  18. 56. CROSS SECTION OF POWERHOUSE, PROJECT 1933, EXHIBIT F, SANTA ...

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

    56. CROSS SECTION OF POWERHOUSE, PROJECT 1933, EXHIBIT F, SANTA ANA POWERHOUSE NO. 1. SCE drawing no. 5206856 (no date; FERC no. 1933-46). - Santa Ana River Hydroelectric System, SAR-1 Powerhouse, Redlands, San Bernardino County, CA

  19. Photocopy of longitudinal, cross sections and roof plan of the ...

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

    Photocopy of longitudinal, cross sections and roof plan of the C.B. & Q. R.R. roundhouse and locomotive shops. June 1980. - Chicago, Burlington & Quincy Railroad, Roundhouse & Shops, Broadway & Spring Streets, Aurora, Kane County, IL

  20. Photocopy of "sheet 6 of 8" showing cross section of ...

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

    Photocopy of "sheet 6 of 8" showing cross section of house, front elevation, fire finder stand, hip roof cap, and shiplap roof sheathing. - Badger Mountain Lookout, .125 mile northwest of Badger Mountain summit, East Wenatchee, Douglas County, WA

  1. 12. CLOSEUP VIEW OF CROSS SECTION OF SPILLWAY FIFTY FEET ...

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

    12. CLOSE-UP VIEW OF CROSS SECTION OF SPILLWAY FIFTY FEET FROM LAKESHORE, SHOWING REMAINS OF SPILLWAY TIMBERS, LOOKING WEST - Three Bears Lake & Dams, North of Marias Pass, East Glacier Park, Glacier County, MT

  2. 4. DETAIL VIEW OF CROSS SECTION OF STRUCTURE, SHOWING EXTERIOR ...

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

    4. DETAIL VIEW OF CROSS SECTION OF STRUCTURE, SHOWING EXTERIOR FACINGS LINED WITH RUBBLE BACKING AND EARTH INFILL, LOOKING EAST - Rock Wall, North side of Battle Creek Canyon, Shingletown, Shasta County, CA

  3. Local Deplanation Of Double Reinforced Beam Cross Section Under Bending

    NASA Astrophysics Data System (ADS)

    Baltov, Anguel; Yanakieva, Ana

    2015-12-01

    Bending of beams, double reinforced by means of thin composite layers, is considered in the study. Approximate numerical solution is proposed, considering transitional boundary areas, where smooth quadratic transition of the elasticity modulus and deformations take place. Deplanation of the cross section is also accounted for in the areas. Their thickness is found equalizing the total stiffness of the cross section and the layer stiffness. Deplanation of the cross section of the transitional area is determined via the longitudinal deformation in the reinforcing layer, accounting for the equilibrium between the internal and the external moment, generated by the longitudinal stresses in the cross section. A numerical example is given as an illustration demonstrating model's plausibility. The model allows the design and the calculation of recycled concrete beams double reinforced by means of thin layers. The approach is in agreement with modern design of nearly zero energy buildings (NZEB).

  4. Viscosity cross sections for the heavy noble gases

    NASA Astrophysics Data System (ADS)

    McEachran, Robert P.; Stauffer, Allan Daniel

    2015-04-01

    We have calculated viscosity cross sections for argon, krypton and xenon from zero to 1 keV using the phase shifts from our previous publication [R.P. McEachran, A.D. Stauffer, Eur. Phys. J. D 68, 153 (2014)] which presented total elastic and momentum transfer cross sections for these gases. As previously, we present simple analytic fits to our results to aid in modelling plasmas containing these atoms. By using the current results and those in reference [R.P. McEachran, A.D. Stauffer, Eur. Phys. J. D 68, 153 (2014)] the first two `partial cross sections' used in the general moment method of solving the Boltzmann equation can be obtained. The agreement of our viscosity cross sections with experimentally derived results indicates the overall reliability of our calculations.

  5. 8. VIEW OF CROSS SECTION OF THE EASTERNMOST WALL SEGMENT ...

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

    8. VIEW OF CROSS SECTION OF THE EASTERNMOST WALL SEGMENT THAT SHOWS THE TRENCHING AND 1960 PIPELINE CORRIDOR BETWEEN THE WALL SEGMENTS, LOOKING WEST-NORTHWEST - Rock Wall, North side of Battle Creek Canyon, Shingletown, Shasta County, CA

  6. 15. Power plant elevations and cross sections, sheet 64 of ...

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

    15. Power plant elevations and cross sections, sheet 64 of 130 - Naval Air Station Fallon, Power Plant, 800 Complex, off Carson Road near intersection of Pasture & Berney Roads, Fallon, Churchill County, NV

  7. Photoionization cross section for He in the hyperspherical coordinate method

    SciTech Connect

    Miller, D.L.; Starace, A.F.

    1980-01-01

    In order to more fully explore the role of electron correlations in the photoionization process the hyperspherical coordinate method of Macek was employed in calculating photoionization cross sections of He. Results are presented and discussed. (WHK)

  8. Radiative neutron capture cross sections on 176Lu at DANCE

    NASA Astrophysics Data System (ADS)

    Roig, O.; Jandel, M.; Méot, V.; Bond, E. M.; Bredeweg, T. A.; Couture, A. J.; Haight, R. C.; Keksis, A. L.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.

    2016-03-01

    The cross section of the neutron capture reaction 176Lu(n ,γ ) has been measured for a wide incident neutron energy range with the Detector for Advanced Neutron Capture Experiments at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be (1912 ±132 ) b for one of the Lu natural isotopes, 176Lu. The resonance part was measured and compared to the Mughabghab's atlas using the R -matrix code, sammy. At higher neutron energies the measured cross sections are compared to ENDF/B-VII.1, JEFF-3.2, and BRC evaluated nuclear data. The Maxwellian averaged cross sections in a stellar plasma for thermal energies between 5 keV and 100 keV were extracted using these data.

  9. Scaling Cross Sections for Ion-atom Impact Ionization

    SciTech Connect

    Igor D. Kaganovich; Edward Startsev; Ronald C. Davidson

    2003-06-06

    The values of ion-atom ionization cross sections are frequently needed for many applications that utilize the propagation of fast ions through matter. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. This paper briefly summarizes the most important theoretical results and approaches to cross section calculations in order to place the discussion in historical perspective and offer a concise introduction to the topic. Based on experimental data and theoretical predictions, a new fit for ionization cross sections is proposed. The range of validity and accuracy of several frequently used approximations (classical trajectory, the Born approximation, and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.

  10. Totem Results on Elastic Scattering and Total Cross-Section

    NASA Astrophysics Data System (ADS)

    Kašpar, Jan

    2015-06-01

    TOTEM is an LHC experiment dedicated to forward hadronic physics. In this contribution, an update on two main parts of its physics programme is given: proton-proton elastic scattering and total cross-section.

  11. 56. CROSS SECTIONS OF CANAL AND TUNNELS. POWER CANAL, SALT ...

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

    56. CROSS SECTIONS OF CANAL AND TUNNELS. POWER CANAL, SALT RIVER RESERVOIR Courtesy of U.S.G.S., Reclamation Service - Roosevelt Power Canal & Diversion Dam, Parallels Salt River, Roosevelt, Gila County, AZ

  12. A new technique for dosimetry reaction cross-section evaluation

    SciTech Connect

    Badikov, S.A.

    2011-07-01

    Document available in abstract form only, full text of document follows: An objective of this paper is a unification of the procedure for dosimetry reaction cross-section evaluation. A set of requirements for the unified evaluation procedure is presented. A new code (ORTHO) was developed in order to meet these requirements. A statistical model, an algorithm, and the basic formulae employed in the code are described. The code was used for Ti48(n,p) reaction cross-section evaluation. The results of the evaluation are compared to International Reactor Dosimetry File (IRDF)-2002 data. The evaluated cross-sections and their correlations from this work are in good agreement with the IRDF-2002 evaluated data, whereas the uncertainties of the evaluated cross-sections are inconsistent. (authors)

  13. 36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER ...

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

    36. CROSS SECTIONAL VIEW OF ORIGINAL HORSE MESA DAM POWER PLANT, LOOKING NORTH. ONLY TWO OF THE THREE UNITS ARE VISIBLE - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  14. 20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY ...

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

    20. CROSS SECTIONAL VIEW OF HORSE MESA, SHOWING RIGHT SPILLWAY SUPERSTRUCTURE AND CONCRETE PLACEMENT LINES August 2, 1927 - Horse Mesa Dam, Salt River, 65 miles East of Phoenix, Phoenix, Maricopa County, AZ

  15. Section B, general view of steel cross with new World ...

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

    Section B, general view of steel cross with new World Trade Center 7 in background, looking northwest. (BH) - World Trade Center Site, Bounded by Vesey, Church, Liberty Streets, & Route 9A, New York County, NY

  16. Extraordinarily Large Optical Cross Section for Localized Single Nanoresonator

    NASA Astrophysics Data System (ADS)

    Zhou, Ming; Shi, Lei; Zi, Jian; Yu, Zongfu

    2015-07-01

    Using an optical nanoresonator to realize extreme concentration of light at subwavelength nanoscale dimensions is of both fundamental and practical significance. Unfortunately, the optical cross section of an isotropic nanoresonator is determined by the resonant wavelength, which unfavorably limits the highest concentration ratio. Here we show that the cross section of a localized subwavelength resonator can be drastically enhanced by orders of magnitude. A single microscopic nanoresonator could exhibit a macroscopic optical cross section. We further show that the enhancement can be implemented in simple dielectric structures that are readily compatible with optoelectronic integration. The giant optical cross section of a nano-object provides a versatile platform to create extremely strong light-matter interactions at the nanoscale.

  17. On the interweaving of partial cross sections of different parity

    NASA Technical Reports Server (NTRS)

    Devries, P. L.; George, T. F.

    1979-01-01

    Partial cross sections of definite parity, calculated for electronic-rotational energy transfer in the F +H2 collision system, interweave with increasing total angular momentum J. An explanation, in terms of diabatic curve crossings induced by the centrifugal potential in the body-fixed coordinate system, predicts the interweaving to occur only in systems having half-integer J.

  18. Nucleon-nucleon cross sections in nuclear matter

    SciTech Connect

    Schulze, H.; Schnell, A.; Roepke, G.; Lombardo, U.

    1997-06-01

    We provide a microscopic calculation of neutron-proton and neutron-neutron cross sections in symmetric nuclear matter at various densities, using the Brueckner-Hartree-Fock approximation scheme with the Paris potential. We investigate separately the medium effects on the effective mass and on the scattering amplitude. We determine average cross sections suitable for application in the dynamical simulation of heavy ion collisions, including a parametrization of their energy and density dependence. {copyright} {ital 1997} {ital The American Physical Society}

  19. Differential double capture cross sections in p+He collisions

    SciTech Connect

    Schulz, M.; Brand, J. A.; Vajnai, T.

    2007-02-15

    We have measured differential double capture cross sections for 15 to 150 keV p+He collisions. We also analyzed differential double to single capture ratios, where we find pronounced peak structures. An explanation of these structures probably requires a quantum-mechanical description of elastic scattering between the projectile and the target nucleus. Strong final-state correlations have a large effect on the magnitude of the double capture cross sections.

  20. Top Quark Pair Production Cross Section at the Tevatron

    SciTech Connect

    Peters, Reinhild Yvonne

    2015-09-25

    The top quark, discovered in 1995 by the CDF and D0 collaborations at the Tevatron proton antiproton collider at Fermilab, has undergone intense studies in the last 20 years. Currently, CDF and D0 converge on their measurements of top-antitop quark production cross sections using the full Tevatron data sample. In these proceedings, the latest results on inclusive and differential measurements of top-antitop quark production cross sections at the Tevatron are reported.

  1. Absorption cross sections of the ClO dimer

    NASA Technical Reports Server (NTRS)

    Huder, K. J.; DeMore, W. B.

    1995-01-01

    The absorption cross sections of the ClO dimer, ClOOCl, are important to the photochemistry of ozone depletion in the Antarctic. In this work, new measurements were made of the dimer cross sections at 195 K. the results yield somewhat lower values in the long wavelength region, compared to those currently recommended in the NASA data evaluation (JPL 94-26). The corresponding solar photodissociation rates in the Antarctic are reduced by about 40%.

  2. Experimental nuclear cross sections for spacecraft shield analysis

    NASA Technical Reports Server (NTRS)

    Peelle, R. W.

    1972-01-01

    Experiments have been performed to validate and to supplement the intranuclear cascade model as a method for estimating cross sections of importance to spacecraft shield design. The experimental situation is inconclusive particularly for neutron-producing reactions, but is relatively sound for reaction cross sections and for proton spectra at several hundred MeV at medium forward angles. Secondary photon contributions are imprecisely known.

  3. Studies of 54,56Fe Neutron Scattering Cross Sections

    NASA Astrophysics Data System (ADS)

    Hicks, S. F.; Vanhoy, J. R.; French, A. J.; Henderson, S. L.; Howard, T. J.; Pecha, R. L.; Santonil, Z. C.; Crider, B. P.; Liu, S.; McEllistrem, M. T.; Peters, E. E.; Prados-Estévez, F. M.; Ross, T. J.; Yates, S. W.

    2015-05-01

    Elastic and inelastic neutron scattering differential cross sections and γ-ray production cross sections have been measured on 54,56Fe at several incident energies in the fast neutron region between 1.5 and 4.7 MeV. All measurements were completed at the University of Kentucky Accelerator Laboratory (UKAL) using a 7-MV Model CN Van de Graaff accelerator, along with the neutron production and neutron and γ-ray detection systems located there. The facilities at UKAL allow the investigation of both elastic and inelastic scattering with nearly mono-energetic incident neutrons. Time-of-flight techniques were used to detect the scattered neutrons for the differential cross section measurements. The measured cross sections are important for fission reactor applications and also for testing global model calculations such as those found at ENDF, since describing both the elastic and inelastic scattering is important for determining the direct and compound components of the scattering mechanism. The γ-ray production cross sections are used to determine cross sections to unresolved levels in the neutron scattering experiments. Results from our measurements and comparisons to model calculations are presented.

  4. Methodology Series Module 3: Cross-sectional Studies

    PubMed Central

    Setia, Maninder Singh

    2016-01-01

    Cross-sectional study design is a type of observational study design. In a cross-sectional study, the investigator measures the outcome and the exposures in the study participants at the same time. Unlike in case–control studies (participants selected based on the outcome status) or cohort studies (participants selected based on the exposure status), the participants in a cross-sectional study are just selected based on the inclusion and exclusion criteria set for the study. Once the participants have been selected for the study, the investigator follows the study to assess the exposure and the outcomes. Cross-sectional designs are used for population-based surveys and to assess the prevalence of diseases in clinic-based samples. These studies can usually be conducted relatively faster and are inexpensive. They may be conducted either before planning a cohort study or a baseline in a cohort study. These types of designs will give us information about the prevalence of outcomes or exposures; this information will be useful for designing the cohort study. However, since this is a 1-time measurement of exposure and outcome, it is difficult to derive causal relationships from cross-sectional analysis. We can estimate the prevalence of disease in cross-sectional studies. Furthermore, we will also be able to estimate the odds ratios to study the association between exposure and the outcomes in this design. PMID:27293245

  5. Updating the IST-LISBON electron cross sections for nitrogen

    NASA Astrophysics Data System (ADS)

    Alves, L. L.; Sombreireiro, L.; Viegas, P.; Guerra, V.

    2013-09-01

    In this work we update the complete and consistent set of nitrogen (N2) electron-impact cross-section with the IST-LISBON database, available on the LXCat website. The update has extended, in energy scale up to 1 keV, the cross sections for effective momentum-transfer, excitation to electronic states and ionization. The set further accounts for excitation to rotational and vibrational excited states. Calculations using BOLSIG + with the new cross sections give swarm parameters in very good agreement with available experimental data for the reduced mobility, the characteristic energy and the reduced ionization coefficient, for a very extended E / N range up to 1000 Td. The influence of rotational excitations/de-excitations at low E / N and different rotational temperatures is discussed. A critical evaluation of similarities and differences with sets of N2 cross sections from other databases is carried out. Moreover, the procedure to de-convolute global cross sections into state-to-state vibrational level dependent cross sections is outlined and discussed. Work partially supported by FCT (Pest-OE/SADG/LA0010/2011).

  6. Absolute cross section for recoil detection of deuterium

    NASA Astrophysics Data System (ADS)

    Besenbacher, F.; Stensgaard, I.; Vase, P.

    1986-04-01

    The D( 4He, D) 4He cross section used for recoil detection of deuterium (D) has been calibrated on an absolute scale against the cross section of the D( 3He, α)p nuclear reaction which is often used for D profiling. For 4He energies ranging from 0.8 to ~1.8 MeV. the D( 4He, D) 4He cross section varies only slightly with incident energy and recoil angle θ (for 0° ⩽ 8 ⩽ 35°) and has a value of ~ 500 mb/sr which is significantly higher than the ~ 65 mb/sr c.m.s. cross section of the D( 3He, α)p nuclear reaction. For 4He energies ranging from ~ 1.9 to ~ 2.3 MeV, the D( 4He,D) 4He cross section exhibits a fairly narrow resonance peak (fwhm ~ 70 keV), with a maximum value (for θ = 0°) of ~ 8.5 b/sr, corresponding to a 4He energy of ~ 2130 keV. The large values of the cross section in connection with the described energy dependence makes the use of forward-recoil detection of D attractive for many purposes, e.g., D Jepth profiling (with an extreme gain in sensitivity), absolute concentration or coverage measurements, and lattice-location experiments by transmission channeling.

  7. Mental visualization of objects from cross-sectional images

    PubMed Central

    Wu, Bing; Klatzky, Roberta L.; Stetten, George D.

    2011-01-01

    We extended the classic anorthoscopic viewing procedure to test a model of visualization of 3D structures from 2D cross-sections. Four experiments were conducted to examine key processes described in the model, localizing cross-sections within a common frame of reference and spatiotemporal integration of cross sections into a hierarchical object representation. Participants used a hand-held device to reveal a hidden object as a sequence of cross-sectional images. The process of localization was manipulated by contrasting two displays, in-situ vs. ex-situ, which differed in whether cross sections were presented at their source locations or displaced to a remote screen. The process of integration was manipulated by varying the structural complexity of target objects and their components. Experiments 1 and 2 demonstrated visualization of 2D and 3D line-segment objects and verified predictions about display and complexity effects. In Experiments 3 and 4, the visualized forms were familiar letters and numbers. Errors and orientation effects showed that displacing cross-sectional images to a remote display (ex-situ viewing) impeded the ability to determine spatial relationships among pattern components, a failure of integration at the object level. PMID:22217386

  8. Thermoelastic damping in microrings with circular cross-section

    NASA Astrophysics Data System (ADS)

    Li, Pu; Fang, Yuming; Zhang, Jianrun

    2016-01-01

    Predicting thermoelastic damping (TED) is crucial in the design of high Q micro-resonators. Microrings are often critical components in many micro-resonators. Some analytical models for TED in microrings have already been developed in the past. However, the previous works are limited to the microrings with rectangular cross-section. The temperature field in the rectangular cross-section is one-dimensional. This paper deals with TED in the microrings with circular cross-section. The temperature field in the circular cross-section is two-dimensional. This paper first presents a 2-D analytical model for TED in the microrings with circular cross-section. Only the two-dimensional heat conduction in the circular cross-section is considered. The heat conduction along the circumferential direction of the microring is neglected in the 2-D model. Then the 2-D model has been extended to cover the circumferential heat conduction, and a 3-D analytical model for TED has been developed. The analytical results from the present 2-D and 3-D models show good agreement with the numerical results of FEM model. The limitations of the present 2-D analytical model are assessed.

  9. General Constraints on Cross Sections Deduced from Surrogate Reactions

    SciTech Connect

    Younes, W

    2003-08-14

    Cross sections that cannot be measured in the laboratory, e.g. because the target lifetime is too short, can be inferred indirectly from a different reaction forming the same compound system, but with a more accessible beam/target combination (the ''surrogate-reaction'' technique). The reactions share the same compound system and a common decay mechanism, but they involve different formation processes. Therefore, an implicit constraint is imposed on the inferred cross section deduced from the measured surrogate-reaction data, through the common decay mechanism. In this paper, the mathematical consequences of this implicit constraint are investigated. General formulas are derived from upper and lower bounds on the inferred cross section, estimated from surrogate data in a procedure which does not require any modeling of the common decay process. As an example, the formulas developed here are applied to the case of the {sup 235}U(n,f) cross section, deduced from {sup 234}U(t,pf) surrogate data. The calculated bounds are not very tight in this particular case. However, by introducing a few qualitative assumptions about the physics of the fission process, meaningful bounds on the deduced cross section are obtained. Upper and lower limits for the cross-section ratio of the (n,f) reaction on the {sup 235}U isomer at E{sub x} = 77 eV relative to the (n,f) reaction on the ground state are also calculated. The generalization of this technique to other surrogate reactions is discussed.

  10. Updated ozone absorption cross section will reduce air quality compliance

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-12-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been re-evaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding 50 years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross-section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  11. Updated ozone absorption cross section will reduce air quality compliance

    NASA Astrophysics Data System (ADS)

    Sofen, E. D.; Evans, M. J.; Lewis, A. C.

    2015-07-01

    Photometric ozone measurements rely upon an accurate value of the ozone absorption cross section at 253.65 nm. This has recently been reevaluated by Viallon et al. (2015) as 1.8 % smaller than the accepted value (Hearn, 1961) used for the preceding fifty years. Thus, ozone measurements that applied the older cross section systematically underestimate the amount of ozone in air. We correct the reported historical surface data from North America and Europe and find that this modest change in cross section has a significant impact on the number of locations that are out of compliance with air quality regulations if the air quality standards remain the same. We find 18, 23, and 20 % increases in the number of sites that are out of compliance with current US, Canadian, and European ozone air quality health standards for the year 2012. Should the new cross section value be applied, it would impact attainment of air quality standards and compliance with relevant clean air acts, unless the air quality target values themselves were also changed proportionately. We draw attention to how a small change in gas metrology has a global impact on attainment and compliance with legal air quality standards. We suggest that further laboratory work to evaluate the new cross section is needed and suggest three possible technical and policy responses should the new cross section be adopted.

  12. Krypton charge exchange cross sections for Hall effect thruster models

    SciTech Connect

    Hause, Michael L.; Prince, Benjamin D.; Bemish, Raymond J.

    2013-04-28

    Following discharge from a Hall effect thruster, charge exchange occurs between ions and un-ionized propellant atoms. The low-energy cations produced can disturb operation of onboard instrumentation or the thruster itself. Charge-exchange cross sections for both singly and doubly charged propellant atoms are required to model these interactions. While xenon is the most common propellant currently used in Hall effect thrusters, other propellants are being considered, in particular, krypton. We present here guided-ion beam measurements and comparisons to semiclassical calculations for Kr{sup +} + Kr and Kr{sup 2+} + Kr cross sections. The measurements of symmetric Kr{sup +} + Kr charge exchange are in good agreement with both the calculations including spin-orbit effects and previous measurements. For the symmetric Kr{sup 2+} + Kr reaction, we present cross section measurements for center-of-mass energies between 1 eV and 300 eV, which spans energies not previously examined experimentally. These cross section measurements compare well with a simple one-electron transfer model. Finally, cross sections for the asymmetric Kr{sup 2+} + Kr {yields} Kr{sup +} + Kr{sup +} reaction show an onset near 12 eV, reaching cross sections near constant value of 1.6 A{sup 2} with an exception near 70-80 eV.

  13. Influence of knee alignment on quadriceps cross-sectional area.

    PubMed

    Sogabe, Akitoshi; Mukai, Naoki; Miyakawa, Shunpei; Mesaki, Noboru; Maeda, Kazuaki; Yamamoto, Tadashi; Gallagher, Philip M; Schrager, Matt; Fry, Andrew C

    2009-10-16

    Previous studies of methods for stimulating the individual muscles composing the quadriceps femoris have not considered the structural features of a subject's knee joint. In this study, we compared the ratios of the individual muscles composing the quadriceps between subjects with different knee alignments using magnetic resonance (MR) imaging. A total of 18 healthy males were examined: 6 normal knees (age, 23.0+/-0.6 yr; femorotibial angle (FTA), 176.8+/-0.4 degrees), 6 genu varum (age, 21.8+/-2.9 yr; FTA, 181.7+/-2.6 degrees) and 6 genu valgum (age, 21.0+/-1.6 yr; FTA, 172.3+/-1.5 degrees). The cross-sectional areas (CSAs) of quadriceps muscles were obtained by MR imaging of the entire left thigh. The CSAs of the vastus lateralis (VL), rectus femoris (RF), vastus medialis (VM) and vastus intermedius (VI) muscles were obtained by MR imaging of the entire left thigh in a supine position. The VM/VL ratio was also obtained by dividing the CSA of the VM by that of the VL and compared among the three groups of subjects with different knee alignments. The genu varum group showed a significantly higher %CSA of VM in the CSA of the quadriceps (VM/Quad) (49.0+/-2.6%) than values for the other two groups. The genu valgum group showed significantly higher values of RF/Quad (15.2+/-2.1%) and VL/Quad (40.6+/-4.0%) than the other groups. The VM/VL ratio was significantly higher in the genu varum than in values for the other two groups. This difference in CSA, in respect to knee alignment, may be considered when devising muscle training programs. PMID:19698946

  14. SCWR Once-Through Calculations for Transmutation and Cross Sections

    SciTech Connect

    ganda, francesco

    2012-07-01

    It is the purpose of this report to document the calculation of (1) the isotopic evolution and of (2) the 1-group cross sections as a function of burnup of the reference Super Critical Water Reactor (SCWR), in a format suitable for the Fuel Cycle Option Campaign Transmutation Data Library. The reference SCWR design was chosen to be that described in [McDonald, 2005]. Super Critical Water Reactors (SCWR) are intended to operate with super-critical water (i.e. H2O at a pressure above 22 MPa and a temperature above 373oC) as a cooling – and possibly also moderating – fluid. The main mission of the SCWR is to generate lower cost electricity, as compared to current standard Light Water Reactors (LWR). Because of the high operating pressure and temperature, SCWR feature a substantially higher thermal conversion efficiency than standard LWR – i.e. about 45% versus 33%, mostly due to an increase in the exit water temperature from ~300oC to ~500oC – potentially resulting in a lower cost of generated electricity. The coolant remains single phase throughout the reactor and the energy conversion system, thus eliminating the need for pressurizers, steam generators, steam separators and dryers, further potentially reducing the reactor construction capital cost. The SCWR concept presented here is based on existing LWR technology and on a large number of existing fossil-fired supercritical boilers. However, it was concluded in [McDonald, 2005], that: “Based on the results of this study, it appears that the reference SCWR design is not feasible.” This conclusion appears based on the strong sensitivity of the design to small deviations in nominal conditions leading to small effects having a potentially large impact on the peak cladding temperature of some fuel rods. “This was considered a major feasibility issue for the SCWR” [McDonald, 2005]. After a description of the reference SCWR design, the Keno V 3-D single assembly model used for this analysis, as well as the

  15. Transport model based on three-dimensional cross-section generation for TRIGA core analysis

    NASA Astrophysics Data System (ADS)

    Kriangchaiporn, Nateekool

    This dissertation addresses the development of a reactor core physics model based on 3-D transport methodology utilizing 3-D multigroup fuel lattice cross-section generation and core calculation for PSBR. The proposed 3-D transport calculation scheme for reactor core simulations is based on the TORT code. The methodology includes development of algorithms for 2-D and 3-D cross-section generation. The fine- and broad-group structures for the TRIGA cross-section generation problems were developed based on the CPXSD (Contributon and Point-wise Cross-Section Driven) methodology that selects effective group structure. Along with the study of cross section generation, the parametric studies for SN calculations were performed to evaluate the impact of the spatial meshing, angular, and scattering order variables and to obtain the suitable values for cross-section collapsing of the TRIGA cell problem. The TRIGA core loading 2 is used to verify and validate the selected effective group structures. Finally, the 13 group structure was selected to use for core calculations. The results agree with continuous energy for eigenvalues and normalized pin power distribution. The Monte Carlo solutions are used as the references.

  16. A design method for entrance sections of transonic wind tunnels with rectangular cross sections

    NASA Technical Reports Server (NTRS)

    Lionel, L.; Mcdevitt, J. B.

    1975-01-01

    A mathematical technique developed to design entrance sections for transonic or high-speed subsonic wind tunnels with rectangular cross sections is discribed. The transition from a circular cross-section setting chamber to a rectangular test section is accomplished smoothly so as not to introduce secondary flows (vortices or boundary-layer separation) into a uniform test stream. The results of static-pressure measurements in the transition region and of static and total-pressure surveys in the test section of a pilot model for a new facility at the Ames Research Center are presented.

  17. /sup 242/Am/sup m/ fission cross section

    SciTech Connect

    Browne, J.C.; White, R.M.; Howe, R.E.; Landrum, J.H.; Dougan, R.J.; Dupzyk, R.J.

    1984-06-01

    The neutron-induced fission cross section of /sup 242/Am/sup m/ has been measured over the energy region from 10/sup -3/ eV to approx.20 MeV in a series of experiments utilizing a linac-produced ''white'' neutron source and a monoenergetic source of 14.1 MeV neutrons. The cross section was measured relative to that of /sup 235/U in the thermal (0.001 to approx.3 eV) and high energy (1 keV to approx.20 MeV) regions and normalized to the ENDF/B-V /sup 235/U(n,f) evaluated cross section. In the resonance energy region (0.5 eV to 10 keV) the neutron flux was measured using thin lithium glass scintillators and the relative cross section thus obtained was normalized to the thermal energy measurement. This procedure allowed a consistency check between the thermal and high energy data. The cross section data have a statistical accuracy of approx.0.5% at thermal energies and in the 1-MeV energy region, and a systematic uncertainty of approx.5%. We confirmed that /sup 242/Am/sup m/ has the largest thermal fission cross section known with a 2200 m/sec value of 6328 b. Results of a Breit-Wigner sum-of-single-levels analysis of 48 fission resonances up to 20 eV are presented and the connection of these resonance properties to the large thermal cross section is discussed. Our measurements are compared with previously reported results.

  18. ACTIV87: Fast Neutron Activation Cross Section File

    Energy Science and Technology Software Center (ESTSC)

    1993-08-01

    4. HISTORICAL BACKGROUND AND INFORMATION ACTIV87 is a compilation of fast neutron induced activation reaction cross-sections. The compilation covers energies from threshold to 20 MeV and is based on evaluated data taken from other evaluated data libraries and individual evaluations. The majority of these evaluations were performed by using available experimental data. The aforementioned available experimental data were used in the selection of needed parameters for theoretical computations and for normalizing the results of suchmore » computations. Theoretical calculations were also used for interpolation and extrapolation of experimental cross-section data. All of the evaluated data curves were compared with experimental data that had been reported over the four year period preceding 1987. Only those cross-sections not in contradiction with experimental data that was current in 1987 were retained in the activation file, ACTIV87. In cases of several conflicting evaluations, that evaluation was chosen which best corresponded to the experimental data. A few evaluated curves were renormalized in accordance with the results of the latest precision measurements. 5. APPLICATION OF THE DATA 6. SOURCE AND SCOPE OF DATA The following libraries and individual files of evaluated neutron cross-section data were used for the selection of the activation cross-sections: the BOSPOR Library, the Activation File of the Evaluated Nuclear Data Library, the Evaluated Neutron Data File (ENDF/B-V) Activation File, the International Reactor Dosimetry File (IRDF-82), and individual evaluations carried out under various IAEA research contracts. The file of selected reactions contains 206 evaluated cross-section curves of the (n,2n), (n,p) and (n,a) reactions which lead to radioactive products and may be used in many practical applications of neutron activation analysis. Some competing activation reactions, usually with low cross-section values, are given for completeness.« less

  19. Measurement of the 242Pu neutron capture cross section

    NASA Astrophysics Data System (ADS)

    Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; Bucher, B.; Bredeweg, T. A.; Baramsai, B.; Couture, A.; Jandel, M.; Mosby, S.; O'Donnell, J. M.; Ullmann, J. L.; Chyzh, A.; Dance Collaboration

    2015-10-01

    Precision (n,f) and (n, γ) cross sections are important for the network calculations of the radiochemical diagnostic chain for the U.S. DOE's Stockpile Stewardship Program. 242Pu(n, γ) cross section is relevant to the network calculations of Pu and Am. Additionally, new reactor concepts have catalyzed considerable interest in the measurement of improved cross sections for neutron-induced reactions on key actinides. To date, little or no experimental data has been reported on 242Pu(n, γ) for incident neutron energy below 50 keV. A new measurement of the 242Pu(n, γ) reaction was performed with the DANCE together with an improved PPAC for fission-fragment detection at LANSCE during FY14. The relative scale of the 242Pu(n, γ) cross section spans four orders of magnitude for incident neutron energies from thermal to ~ 30 keV. The absolute scale of the 242Pu(n, γ) cross section is set according to the measured 239Pu(n,f) resonance at 7.8 eV; the target was spiked with 239Pu for this measurement. The absolute 242Pu(n, γ) neutron capture cross section is ~ 30% higher than the cross section reported in ENDF for the 2.7 eV resonance. Latest results to be reported. Funded by U.S. DOE Contract No. DE-AC52-07NA27344 (LLNL) and DE-AC52-06NA25396 (LANL). U.S. DOE/NNSA Office of Defense Nuclear Nonproliferation Research and Development. Isotopes (ORNL).

  20. SN-detection in LAr-TPC and the quest for (ν-Ar) cross sections

    SciTech Connect

    Cavanna, F.

    2015-05-15

    Neutrino-nucleus cross sections are of relevance to supernova astrophysics. These cross-sections can be grouped into three categories, those that affect supernova dynamics, supernova nucleosynthesis, and terrestrial supernova neutrino detection, each of which would benefit from experimental study. In this report only the relevance of an accurate knowledge of neutrino-target nucleus cross sections for SN detection will be discussed, in particular for the case of Argon, the active target material of LAr-TPC detectors currently under construction or proposed for future very massive underground experiments.

  1. Error Assessment of Homogenized Cross Sections Generation for Whole Core Neutronic Calculation

    SciTech Connect

    Hursin, Mathieu; Kochunas, Brendan; Downar, Thomas J.

    2007-10-26

    The objective of the work here was to assess the errors introduced by using 2D, few group homogenized cross sections to perform neutronic analysis of BWR problems with significant axial heterogeneities. The 3D method of characteristics code DeCART is used to generate 2-group assembly homogenized cross sections first using a conventional 2D lattice model and then using a full 3D solution of the assembly. A single BWR fuel assembly model based on an advanced BWR lattice design is used with a typical void distribution applied to the fuel channel coolant. This model is validated against an MCNP model. A comparison of the cross sections is performed for the assembly homogenized planar cross sections from the DeCART 3D and DeCART 2D solutions.

  2. Proton Radiography: Cross Section Measurements and Detector Development

    SciTech Connect

    Michael J. Longo; H. R. Gustafson: Durga Rajaram; Turgun Nigmanov

    2010-04-16

    Proton radiography has become an important tool for predicting the performance of stockpiled nuclear weapons. Current proton radiography experiments at LANSCE are confined to relatively small targets on the order of centimeters in size because of the low beam energy. LANL scientists have made radiographs with 12 and 24 GeV protons produced by the accelerator at Brookhaven National Laboratory. These energies are in the range required for hydrotest radiography. The design of a facility for hydrotest radiography requires knowledge of the cross sections for producing high-energy particles in the forward direction, which are incorporated into the Monte Carlo simulation used in designing the beam and detectors. There are few existing measurements of neutron production cross sections for proton-nuclei interactions in the 50 GeV range, and almost no data exist for forward neutron production, especially for heavy target nuclei. Thus the data from the MIPP EMCAL and HCAL, for which our group was responsible, are critical to proton radiography. Since neutrons and photons cannot be focused by magnets, they cause a background “fog” on the images. This problem can be minimized by careful design of the focusing system and detectors. The purpose of our research was to measure forward production of neutrons produced by high-energy proton beams striking a variety of targets. The forward-going particles carry most of the energy from a high-energy proton interaction, so these are the most important to proton radiography. This work was carried out in conjunction with the Fermilab E-907 (MIPP) collaboration. Our group was responsible for designing and building the E907 forward neutron and photon calorimeters. With the support of our Stewardship Science Academic Alliances grants, we were able to design, build, and commission the calorimeters on budget and ahead of schedule. The MIPP experiment accumulated a large amount of data in the first run that ended in early 2006. Our group has

  3. Improved Actinide Neutron Capture Cross Sections Using Accelerator Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Bauder, W.; Pardo, R. C.; Kondev, F. G.; Kondrashev, S.; Nair, C.; Nusair, O.; Palchan, T.; Scott, R.; Seweryniak, D.; Vondrasek, R.; Collon, P.; Paul, M.; Youinou, G.; Salvatores, M.; Palmotti, G.; Berg, J.; Maddock, T.; Imel, G.

    2014-09-01

    The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are developing a technique to inject solid material into the ECR with laser ablation. With laser ablation, we can better control material injection and potentially increase efficiency in the ECR, thus creating less contamination in the source and reducing cross talk. I will present work on the laser ablation system and preliminary results from our AMS measurements. The MANTRA (Measurement of Actinide Neutron TRAnsmutations) project will improve energy-integrated neutron capture cross section data across the actinide region. These data are incorporated into nuclear reactor models and are an important piece in understanding Generation IV reactor designs. We will infer the capture cross sections by measuring isotopic ratios from actinide samples, irradiated in the Advanced Test Reactor at INL, with Accelerator Mass Spectrometry (AMS) at ATLAS (ANL). The superior sensitivity of AMS allows us to extract multiple cross sections from a single sample. In order to analyze the large number of samples needed for MANTRA and to meet the goal of extracting multiple cross sections per sample, we have made a number of modifications to the AMS setup at ATLAS. In particular, we are

  4. Inclined Bodies of Various Cross Sections at Supersonic Speeds

    NASA Technical Reports Server (NTRS)

    Jorgensen, Leland H.

    1958-01-01

    To aid in assessing effects of cross-sectional shape on body aerodynamics, the forces and moments have been measured for bodies with circular, elliptic, square, and triangular cross sections at Mach numbers 1.98 and 3.88. Results for bodies with noncircular cross sections have been compared with results for bodies of revolution having the same axial distribution of cross-sectional area (and, thus, the same equivalent fineness ratio). Comparisons have been made for bodies of fineness ratios 6 and 10 at angles of attack from 0 deg to about 20 deg and for Reynolds numbers, based on body length, of 4.0 x 10(exp 6) and 6.7 x 10(exp 6). The results of this investigation show that distinct aerodynamic advantages can be obtained by using bodies with noncircular cross sections. At certain angles of bank, bodies with elliptic, square, and triangular cross sections develop considerably greater lift and lift-drag ratios than equivalent bodies of revolution. For bodies with elliptic cross sections, lift and pitching-moment coefficients can be correlated with corresponding coefficients for equivalent circular bodies. It has been found that the ratios of lift and pitching-moment coefficients for an elliptic body to those for an equivalent circular body are practically constant with change in both angle of attack and Mach number. These lift and moment ratios are given very accurately by slender-body theory. As a result of this agreement, the method of NACA Rep. 1048 for computing forces and moments for bodies of revolution has been simply extended to bodies with elliptic cross sections. For the cases considered (elliptic bodies of fineness ratios 6 and 10 having cross-sectional axis ratios of 1.5 and 2), agreement of theory with experiment is very good. As a supplement to the force and moment results, visual studies of the flow over bodies have been made by use of the vapor-screen, sublimation, and white-lead techniques. Photographs from these studies are included in the report.

  5. Employee engagement within the NHS: a cross-sectional study

    PubMed Central

    Jeve, Yadava Bapurao; Oppenheimer, Christina; Konje, Justin

    2015-01-01

    Background: Employee engagement is the emotional commitment of the employee towards the organisation. We aimed to analyse baseline work engagement using Utrecht Work Engagement Scale (UWES) at a teaching hospital. Methods: We have conducted a cross-sectional study within the National Health Service (NHS) Teaching Hospital in the UK. All participants were working age population from both genders directly employed by the hospital. UWES has three constituting dimensions of work engagement as vigor, dedication, and absorption. We conducted the study using UWES-9 tool. Outcome measures were mean score for each dimension of work engagement (vigor, dedication, absorption) and total score compared with control score from test manual. Results: We found that the score for vigor and dedication is significantly lower than comparison group (P< 0.0001 for both). The score for absorption was significantly higher than comparison group (P< 0.0001). However, total score is not significantly different. Conclusion: The study shows that work engagement level is below average within the NHS employees. Vigor and dedication are significantly lower, these are characterised by energy, mental resilience, the willingness to invest one’s effort, and persistence as well as a sense of significance, enthusiasm, inspiration, pride, and challenge. The NHS employees are immersed in work. Urgent need to explore strategies to improve work engagement as it is vital for improving productivity, safety and patient experience PMID:25674571

  6. Electromagnetic Dissociation Cross Sections using Weisskopf-Ewing Theory

    NASA Technical Reports Server (NTRS)

    Adamczyk, Anne M.; Norbury, John W.

    2011-01-01

    It is important that accurate estimates of crew exposure to radiation are obtained for future long-term space missions. Presently, several space radiation transport codes exist to predict the radiation environment, all of which take as input particle interaction cross sections that describe the nuclear interactions between the particles and the shielding material. The space radiation transport code HZETRN uses the nuclear fragmentation model NUCFRG2 to calculate Electromagnetic Dissociation (EMD) cross sections. Currently, NUCFRG2 employs energy independent branching ratios to calculate these cross sections. Using Weisskopf-Ewing (WE) theory to calculate branching ratios, however, is more advantageous than the method currently employed in NUCFRG2. The WE theory can calculate not only neutron and proton emission, as in the energy independent branching ratio formalism used in NUCFRG2, but also deuteron, triton, helion, and alpha particle emission. These particles can contribute significantly to total exposure estimates. In this work, photonuclear cross sections are calculated using WE theory and the energy independent branching ratios used in NUCFRG2 and then compared to experimental data. It is found that the WE theory gives comparable, but mainly better agreement with data than the energy independent branching ratio. Furthermore, EMD cross sections for single neutron, proton, and alpha particle removal are calculated using WE theory and an energy independent branching ratio used in NUCFRG2 and compared to experimental data.

  7. Theoretical Formalism To Estimate the Positron Scattering Cross Section.

    PubMed

    Singh, Suvam; Dutta, Sangita; Naghma, Rahla; Antony, Bobby

    2016-07-21

    A theoretical formalism is introduced in this article to calculate the total cross sections for positron scattering. This method incorporates positron-target interaction in the spherical complex optical potential formalism. The study of positron collision has been quite subtle until now. However, recently, it has emerged as an interesting area due to its role in atomic and molecular structure physics, astrophysics, and medicine. With the present method, the total cross sections for simple atoms C, N, and O and their diatomic molecules C2, N2, and O2 are obtained and compared with existing data. The total cross section obtained in the present work gives a more consistent shape and magnitude than existing theories. The characteristic dip below 10 eV is identified due to the positronium formation. The deviation of the present cross section with measurements at energies below 10 eV is attributed to the neglect of forward angle-discrimination effects in experiments, the inefficiency of additivity rule for molecules, empirical treatment of positronium formation, and the neglect of annihilation reactions. In spite of these deficiencies, the present results show consistent behavior and reasonable agreement with previous data, wherever available. Besides, this is the first computational model to report positron scattering cross sections over the energy range from 1 to 5000 eV. PMID:27333337

  8. Updated compilation of electron-Cl2 scattering cross sections

    NASA Astrophysics Data System (ADS)

    Gregório, J.; Pitchford, L. C.

    2012-06-01

    We present a set of cross sections for electron scattering from ground state neutral chlorine molecules in the energy range from 0.01 to 100 eV. This cross section set is based on the recommendations in the review paper by Christophorou and Olthoff (1999 J. Phys. Chem. Ref. Data 28 131) and on more recently published theoretical and experimental results. These cross sections are used as input to a Boltzmann equation solver to yield the electron energy distribution as a function of E/N, the ratio of the electric field strength to neutral density, from which electron transport and rate coefficients (swarm parameters) in gas mixtures containing Cl2 are obtained. Reasonable agreement with the more reliable of the measured swarm parameters is obtained after slightly adjusting the magnitudes of some of the cross sections. While this agreement validates to some extent the cross section set, it is important to note that swarm data in Cl2-containing mixtures are limited and that there is a critical need for further measurements.

  9. Electron collision cross sections for H{sub 2} II

    SciTech Connect

    Itoh, H.; Wada, H.; Ikuta, N.

    1993-12-01

    It is now an open but serious problem that the vibrational excitation cross sections of H{sub 2} molecule theoretically obtained by Morrison and that deduced by England from the swarm data disagree to each other. The results of beam experiment, on the other hand, agree with the theoretical cross section. Examinations in order to find the cause of these discrepancies have been carried out using the FTI method. The authors obtained the cross sections which fit to the drift velocity data and the D{sub {tau}}/{mu} data independently, but it has been impossible to obtain a cross section that fits to both of them. Theoretically derived cross section for vibrational excitation by Morrison can not give swarm parameters that agree with the data of swarm experiments. These facts show that there may be a fault in the present swarm theory. A possible cause of errors is the anisotropy in scatterings which has not been strictly included to the analyses.

  10. EDDIX--a database of ionisation double differential cross sections.

    PubMed

    MacGibbon, J H; Emerson, S; Liamsuwan, T; Nikjoo, H

    2011-02-01

    The use of Monte Carlo track structure is a choice method in biophysical modelling and calculations. To precisely model 3D and 4D tracks, the cross section for the ionisation by an incoming ion, double differential in the outgoing electron energy and angle, is required. However, the double differential cross section cannot be theoretically modelled over the full range of parameters. To address this issue, a database of all available experimental data has been constructed. Currently, the database of Experimental Double Differential Ionisation Cross sections (EDDIX) contains over 1200 digitalised experimentally measured datasets from the 1960s to present date, covering all available ion species (hydrogen to uranium) and all available target species. Double differential cross sections are also presented with the aid of an eight parameter functions fitted to the cross sections. The parameters include projectile species and charge, target nuclear charge and atomic mass, projectile atomic mass and energy, electron energy and deflection angle. It is planned to freely distribute EDDIX and make it available to the radiation research community for use in the analytical and numerical modelling of track structure. PMID:21113060

  11. Simulation of multistatic and backscattering cross sections for airborne radar

    NASA Astrophysics Data System (ADS)

    Biggs, Albert W.

    1986-07-01

    In order to determine susceptibilities of airborne radar to electronic countermeasures and electronic counter-countermeasures simulations of multistatic and backscattering cross sections were developed as digital modules in the form of algorithms. Cross section algorithms are described for prolate (cigar shape) and oblate (disk shape) spheroids. Backscattering cross section algorithms are also described for different categories of terrain. Backscattering cross section computer programs were written for terrain categorized as vegetation, sea ice, glacial ice, geological (rocks, sand, hills, etc.), oceans, man-made structures, and water bodies. PROGRAM SIGTERRA is a file for backscattering cross section modules of terrain (TERRA) such as vegetation (AGCROP), oceans (OCEAN), Arctic sea ice (SEAICE), glacial snow (GLASNO), geological structures (GEOL), man-made structures (MAMMAD), or water bodies (WATER). AGCROP describes agricultural crops, trees or forests, prairies or grassland, and shrubs or bush cover. OCEAN has the SLAR or SAR looking downwind, upwind, and crosswind at the ocean surface. SEAICE looks at winter ice and old or polar ice. GLASNO is divided into a glacial ice and snow or snowfields. MANMAD includes buildings, houses, roads, railroad tracks, airfields and hangars, telephone and power lines, barges, trucks, trains, and automobiles. WATER has lakes, rivers, canals, and swamps. PROGRAM SIGAIR is a similar file for airborne targets such as prolate and oblate spheroids.

  12. Can cross sections be accurately known for priori?

    SciTech Connect

    Pigni,M.T.; Dietrich, F.S.; Herman, M.; Oblozinsky, P.

    2008-06-24

    Distinct maxima and minima in the neutron total cross section uncertainties were observed in our large scale covariance calculations using a spherical optical potential. In this contribution we investigate the physical origin of this oscillating structure. Specifically, we analyze the case of neutron reactions on {sup 56}Fe, for which total cross section uncertainties are characterized by the presence of five distinct minima at 0.1, 1.1, 5, 25, and 70 MeV. To investigate their origin, we calculated total cross sections by perturbing the real volume depth V{sub v} by its expected uncertainty {+-}{Delta}V{sub v}. Inspecting the effect of this perturbation on the partial wave cross sections we found that the first minimum (at 0.1 MeV) is exclusively due to the contribution of the s-wave. On the other hand, the same analysis at 1.1 MeV showed that the minimum is the result of the interplay between s-, p-, and d-waves; namely the change in the s-wave happens to be counterbalanced by changes in the p- and d-waves. Similar considerations can be extended for the third minimum, although it can be also explained in terms of the Ramsauer effect as well as the other ones (at 25 and 70 MeV). We discuss the potential importance of these minima for practical applications as well as the implications of this work for the uncertainties in total and absorption cross sections.

  13. Electron Impact Ionization Cross Sections in Rb and Cs.

    NASA Astrophysics Data System (ADS)

    Reddish, T. J.; Lukomski, M.; Sutton, S.; Kedzierski, W.; McConkey, J. W.; Bartschat, K.; Bartlett, P. L.; Stelbovics, A. T.; Bray, I.

    2006-05-01

    We present a new atom trapping technique for determining absolute, total ionisation cross sections (TICS) out of an excited atom. The novel feature of this method is in utilizing Doppler cooling of neutral atoms to determine ionisation cross sections. This fluorescence-monitoring experiment, which is a variant of the `trap loss' technique, has enabled us to obtain the experimental electron impact ionisation cross sections out of the Cs 6^2P3/2 excited state between 7 - 400 eV. New CCC, R-Matrix with Pseudo-States (RMPS), and Born approximation single ionisation cross sections (SICS) are also presented for both the ground and excited states of Cs and Rb, and compared with the available experimental data. The comparison of the results reveals the importance of the autoionisation and multiple ionisation contributions to the TICS. The autoionisation contribution appears to be substantial for ionisation out of the Cs 6^2P and Rb 5^2P excited states; ˜ 3-4 larger than the direct ionisation contribution predicted by CCC at ˜ 30-50 eV. This surprising result shows the importance of multi-electron processes in determining the ionisation cross sections of heavy alkali atoms.

  14. Experience With the SCALE Criticality Safety Cross Section Libraries

    SciTech Connect

    Bowman, S.M.

    2000-08-21

    This report provides detailed information on the SCALE criticality safety cross-section libraries. Areas covered include the origins of the libraries, the data on which they are based, how they were generated, past experience and validations, and performance comparisons with measured critical experiments and numerical benchmarks. The performance of the SCALE criticality safety cross-section libraries on various types of fissile systems are examined in detail. Most of the performance areas are demonstrated by examining the performance of the libraries vs critical experiments to show general trends and weaknesses. In areas where directly applicable critical experiments do not exist, performance is examined based on the general knowledge of the strengths and weaknesses of the cross sections. In this case, the experience in the use of the cross sections and comparisons with the results of other libraries on the same systems are relied on for establishing acceptability of application of a particular SCALE library to a particular fissile system. This report should aid in establishing when a SCALE cross-section library would be expected to perform acceptably and where there are known or suspected deficiencies that would cause the calculations to be less reliable. To determine the acceptability of a library for a particular application, the calculational bias of the library should be established by directly applicable critical experiments.

  15. Systematic analysis of reaction cross sections of carbon isotopes

    SciTech Connect

    Horiuchi, W.; Suzuki, Y.; Abu-Ibrahim, B.; Kohama, A.

    2007-04-15

    We systematically analyze total reaction cross sections of carbon isotopes with N= 6-16 on a {sup 12}C target for wide range of incident energy. The intrinsic structure of the carbon isotope is described by a Slater determinant generated from a phenomenological mean-field potential, which reasonably well reproduces the ground-state properties for most of the even N isotopes. We need separate studies not only for odd nuclei but also for {sup 16}C and {sup 22}C to improve their wave functions. The density of the carbon isotope is constructed by eliminating the effect of the center-of-mass motion. For the calculations of the cross sections, we take two schemes, the Glauber approximation and the eikonal model using a global optical potential. Both the reaction models successfully reproduce low and high incident energy data on the cross sections of {sup 12}C, {sup 13}C, and {sup 16}C on {sup 12}C. The calculated reaction cross sections of {sup 15}C are found to be considerably smaller than the empirical values observed at low energy. We find a consistent parametrization of the nucleon-nucleon scattering amplitude, differently from previous ones. Finally, we predict the total reaction cross section of {sup 22}C on {sup 12}C.

  16. AFCI-2.0 Neutron Cross Section Covariance Library

    SciTech Connect

    Herman, M.; Herman, M; Oblozinsky, P.; Mattoon, C.M.; Pigni, M.; Hoblit, S.; Mughabghab, S.F.; Sonzogni, A.; Talou, P.; Chadwick, M.B.; Hale, G.M.; Kahler, A.C.; Kawano, T.; Little, R.C.; Yount, P.G.

    2011-03-01

    materials and fission products, and 20 actinides. Covariances are given in 33-energy groups, from 10?5 eV to 19.6 MeV, obtained by processing with LANL processing code NJOY using 1/E flux. In addition to these 110 files, the library contains 20 files with nu-bar covariances, 3 files with covariances of prompt fission neutron spectra (238,239,240-Pu), and 2 files with mu-bar covariances (23-Na, 56-Fe). Over the period of three years several working versions of the library have been released and tested by ANL and INL reactor analysts. Useful feedback has been collected allowing gradual improvements of the library. In addition, QA system was developed to check basic properties and features of the whole library, allowing visual inspection of uncertainty and correlations plots, inspection of uncertainties of integral quantities with independent databases, and dispersion of cross sections between major evaluated libraries. The COMMARA-2.0 beta version of the library was released to ANL and INL reactor analysts in October 2010. The final version, described in the present report, was released in March 2011.

  17. Gonorrhoea in inner London: results of a cross sectional study.

    PubMed Central

    Low, N.; Daker-White, G.; Barlow, D.; Pozniak, A. L.

    1997-01-01

    OBJECTIVES: To estimate population based incidence rates of gonorrhoea in an inner London area and examine relations with age, ethnic group, and socioeconomic deprivation. DESIGN: Cross sectional study. SETTING: 11 departments of genitourinary medicine in south and central London. SUBJECTS: 1978 first episodes of gonorrhoea diagnosed in 1994 and 1995 in residents of 73 electoral wards in the boroughs of Lambeth, Southwark, and Lewisham who attended any of the departments of genitourinary medicine. MAIN OUTCOME MEASURES: Yearly age, sex, and ethnic group specific rates of gonorrhoea per 100,000 population aged 15-59 years; rate ratios for the effects of age and ethnic group on gonorrhoea rates in women and men before and after adjustment for confounding factors. RESULTS: Overall incidence rates of gonorrhoea in residents of Lambeth, Southwark, and Lewisham were 138.3 cases yearly per 100,000 women and 291.9 cases yearly per 100,000 men aged 15-59 years. At all ages gonorrhoea rates were higher in non-white minority ethnic groups. Rate ratios for the effect of age adjusted for ethnic group and underprivilege were 15.2 (95% confidence interval 11.6 to 19.7) for women and 2.0 (1.7 to 2.5) for men aged 15-19 years compared with those over 30. After deprivation score and age were taken into account, women from black minority groups were 10.5 (8.6 to 12.8) times as likely and men 11.0 (9.7 to 12.6) times as likely as white people to experience gonorrhoea. CONCLUSIONS: Gonorrhoea rates in Lambeth, Southwark, and Lewisham in 1994-5 were six to seven times higher than for England and Wales one year earlier. The presentation of national trends thus hides the disproportionate contribution of ongoing endemic transmission in the study area. Teenage women and young adult men, particularly those from black minority ethnic groups, are the most heavily affected, even when socioeconomic underprivilege is taken into account. There is urgent need for resources for culturally

  18. Measurement of the NP Elastic Cross Section by Neutron Transmission

    NASA Astrophysics Data System (ADS)

    Daub, Brian; Kovash, Michael; Henzl, Vladimir; Shoniyozov, Khayrullo

    2010-11-01

    There are very few previous measurements of the cross section for neutron-proton elastic scattering at energies between 200 and 500 keV. To improve this situation, we used a pulsed proton beam from the Van de Graaff accelerator at the University of Kentucky to produce 200-800 keV neutrons via the ^7Li(p,n)^7Be reaction. We determined the total n-p elastic cross section by measuring the transmission of the neutron beam in samples of CH2 and carbon, using a BC501 liquid scintillator. The cross section obtained by taking ratios between normalized sample-in and sample-out yields is independent of both detector efficiency and dead time.

  19. High Energy Measurement of the Deuteron Photodisintegration Differential Cross Section

    SciTech Connect

    Elaine Schulte

    2002-05-01

    New measurements of the high energy deuteron photodisintegration differential cross section were made at the Thomas Jefferson National Accelerator Facility in Newport News, Virginia. Two experiments were performed. Experiment E96-003 was performed in experimental Hall C. The measurements were designed to extend the highest energy differential cross section values to 5.5 GeV incident photon energy at forward angles. This builds upon previous high energy measurements in which scaling consistent with the pQCD constituent counting rules was observed at 90 degrees and 70 degrees in the center of mass. From the new measurements, a threshold for the onset of constituent counting rule scaling seems present at transverse momentum approximately 1.3 GeV/c. The second experiment, E99-008, was performed in experimental Hall A. The measurements were designed to explore the angular distribution of the differential cross section at constant energy. The measurements were made symmetric about 90 degrees

  20. Cross section versus time delay and trapping probability

    NASA Astrophysics Data System (ADS)

    Luna-Acosta, G. A.; Fernández-Marín, A. A.; Méndez-Bermúdez, J. A.; Poli, Charles

    2016-07-01

    We study the behavior of the s-wave partial cross section σ (k), the Wigner-Smith time delay τ (k), and the trapping probability P (k) as function of the wave number k. The s-wave central square well is used for concreteness, simplicity, and to elucidate the controversy whether it shows true resonances. It is shown that, except for very sharp structures, the resonance part of the cross section, the trapping probability, and the time delay, reach their local maxima at different values of k. We show numerically that τ (k) > 0 at its local maxima, occurring just before the resonant part of the cross section reaches its local maxima. These results are discussed in the light of the standard definition of resonance.

  1. pi+- p differential cross sections at low energies

    SciTech Connect

    H. Denz; P. Amaudruz; J.T. Brack; J. Breitschopf; P. Camerini; J.L. Clark; H. Clement; L. Felawka; E. Fragiacomo; E.F. Gibson; N. Grion; G.J. Hofman; B. Jamieson; E.L. Mathie; R. Meier; G. Moloney; D. Ottewell; O. Patarakin; J.D. Patterson; M.M. Pavan; S. Piano; K. Raywood; R.A. Ristinen; R. Rui; M.E. Sevior; G.R. Smith; J. Stahov; R. Tacik; G.J. Wagner; F. von Wrochem; D.M. Yeomans

    2005-12-03

    Differential cross sections for pi- p and pi+ p elastic scattering were measured at five energies between 19.9 and 43.3 MeV. The use of the CHAOS magnetic spectrometer at TRIUMF, supplemented by a range telescope for muon background suppression, provided simultaneous coverage of a large part of the full angular range, thus allowing very precise relative cross section measurements. The absolute normalization was determined with a typical accuracy of 5 %. This was verified in a simultaneous measurement of muon proton elastic scattering. The measured cross sections show some deviations from phase shift analysis predictions, in particular at large angles and low energies. From the new data we determine the real part of the isospin forward scattering amplitude.

  2. Cross-Sectional Transport Imaging in a Multijunction Solar Cell

    SciTech Connect

    Haegel, Nancy M.; Ke, Chi-Wen; Taha, Hesham; Guthrey, Harvey; Fetzer, C. M.; King, Richard

    2015-06-14

    Combining highly localized electron-beam excitation at a point with the spatial resolution capability of optical near-field imaging, we have imaged carrier transport in a cross-sectioned multijunction (GaInP/GaInAs/Ge) solar cell. We image energy transport associated with carrier diffusion throughout the full width of the middle (GaInAs) cell and luminescent coupling from point excitation in the top cell GaInP to the middle cell. Supporting cathodoluminescence and near-field photoluminescence measurements demonstrate excitation-dependent Fermi level splitting effects that influence cross-sectioned spectroscopy results as well as transport limitations on the spatial resolution of cross-sectional measurements.

  3. Photoabsorption cross section of acetylene in the EUV region

    NASA Technical Reports Server (NTRS)

    Wu, C. Y. R.; Judge, D. L.

    1985-01-01

    The measurement of the absolute photoabsorption cross sections of C2H2 in the 175-740 A region by means of a double ionization chamber is reported. The continuum background source is the synchrotron radiation emitted by the Wisconsin 240 MeV electron storage ring. It is found that the cross sections range from 2 to a maximum of 36 Mb. Two new Rydberg series are identified and the cross section data are applied in the analysis of various sum rules. From the rules, it is shown that the data of C2H2 in the 580-1088 A range may be too low, while the measured ionization transition moment may be too high.

  4. Application of simple ramsauer model to neutron total cross sections

    SciTech Connect

    Bauer, R.W.; Anderson, J.D.; Grimes, S.M.; Madsen, V.A.

    1997-04-29

    The simple nuclear Ramsauer model has been used successfully to fit neutron cross sections for three decades, but has not been widely used because the foundations of the model seem to be so unrealistic. We have shown that the Glauber calculations with the inclusion of refraction and optical model calculations essentially validate this simple model for neutron total cross sections in the neutron energy range of 5-50 MeV. This model yields a simple formula for parameterizing the energy dependence of the neutron cross section. We have applied the model to nuclei ranging from vanadium to bismuth. With the addition of a single parameter, we can improve these fits to less than 1.5%.

  5. Pion Total Cross Section in Nucleon - Nucleon Collisions

    NASA Technical Reports Server (NTRS)

    Norbury, John W.

    2009-01-01

    Total cross section parameterizations for neutral and charged pion production in nucleon - nucleon collisions are compared to experimental data over the projectile momentum range from threshold to 300 GeV. Both proton - proton and proton - neutron reactions are considered. Overall excellent agreement between parameterizations and experiment is found, except for notable disagreements near threshold. In addition, the hypothesis that the neutral pion production cross section can be obtained from the average charged pion cross section is checked. The theoretical formulas presented in the paper obey this hypothesis for projectile momenta below 500 GeV. The results presented provide a test of engineering tools used to calculate the pion component of space radiation.

  6. Measurement of Neutron Capture Cross Sections of Selenium Isotopes

    NASA Astrophysics Data System (ADS)

    Dearmon, Howard D.; Krane, Kenneth S.

    2011-10-01

    There have been numerous measurements of the neutron capture cross sections of the stable Se isotopes, most dating from at least 40 years ago. The various results for individual isotopes are often in poor agreement with one another, but as yet there has been no attempt at a systematic measurement of the capture cross sections leading to all seven radioisotopes formed from capture by natural Se, which range in halflife from 17 s to 120 d. Using cadmium-shielded and unshielded irradiations of natural Se in various irradiation sites in OSU's TRIGA reactor, we have determined the thermal cross sections and resonance integrals for captures leading to ^75,77m,79m,81g,81m,83g,83mSe.

  7. Bias in cross-sectional analyses of longitudinal mediation.

    PubMed

    Maxwell, Scott E; Cole, David A

    2007-03-01

    Most empirical tests of mediation utilize cross-sectional data despite the fact that mediation consists of causal processes that unfold over time. The authors considered the possibility that longitudinal mediation might occur under either of two different models of change: (a) an autoregressive model or (b) a random effects model. For both models, the authors demonstrated that cross-sectional approaches to mediation typically generate substantially biased estimates of longitudinal parameters even under the ideal conditions when mediation is complete. In longitudinal models where variable M completely mediates the effect of X on Y, cross-sectional estimates of the direct effect of X on Y, the indirect effect of X on Y through M, and the proportion of the total effect mediated by M are often highly misleading. PMID:17402810

  8. Lanl Neutron-Induced Fission Cross Section Measurement Program

    NASA Astrophysics Data System (ADS)

    Laptev, A. B.; Tovesson, F.; Hill, T. S.

    2014-09-01

    A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). Combining measurements at two LANSCE facilities, the Lujan Center and the Weapons Neutron Research facility (WNR), cover neutron energies over 10 orders of magnitude: from sub-thermal up to 200 MeV. A parallel-plate fission ionization chamber was used as a fission fragment detector. The 235U(n,f) standard was used as the reference. Fission cross sections have been measured for multiple actinides. The new data presented here completes the suite of long-lived Uranium isotopes that were investigated with this experimental approach. The cross section data are presented in comparison with existing evaluations and previous measurements.

  9. 63Ni (n ,γ ) cross sections measured with DANCE

    NASA Astrophysics Data System (ADS)

    Weigand, M.; Bredeweg, T. A.; Couture, A.; Göbel, K.; Heftrich, T.; Jandel, M.; Käppeler, F.; Lederer, C.; Kivel, N.; Korschinek, G.; Krtička, M.; O'Donnell, J. M.; Ostermöller, J.; Plag, R.; Reifarth, R.; Schumann, D.; Ullmann, J. L.; Wallner, A.

    2015-10-01

    The neutron capture cross section of the s -process branch nucleus 63Ni affects the abundances of other nuclei in its region, especially 63Cu and 64Zn. In order to determine the energy-dependent neutron capture cross section in the astrophysical energy region, an experiment at the Los Alamos National Laboratory has been performed using the calorimetric 4 π BaF2 array DANCE. The (n ,γ ) cross section of 63Ni has been determined relative to the well-known 197Au standard with uncertainties below 15%. Various 63Ni resonances have been identified based on the Q value. Furthermore, the s -process sensitivity of the new values was analyzed with the new network calculation tool NETZ.

  10. Inelastic cross sections for positron scattering from atomic hydrogen

    SciTech Connect

    Weber, M.; Hofmann, A.; Raith, W.; Sperber, W.; Jacobsen, F.; Lynn, K.G.

    1994-12-31

    Positronium formation (Ps) cross sections for positrons impinging on atomic hydrogen were measured in the impact energy range from 13eV to 255eV at the High Intensity Positron (HIP) beam at Brookhaven National Laboratory (BNL). The Ps-formation cross section was found to rise rapidly from the threshold at 6.8eV to a maximum value of (2.98 {plus_minus} 0.18) {times} 10{sup {minus}16} cm{sup 2} for {approx} 15eV positrons. By 75eV it drops below the detection limit of 0.17 {times} 10{sup {minus}16} cm{sup 2} which is the present level of statistical uncertainty. The experiment was modified to enable the measurement of doubly differential scattering cross sections.

  11. Aerodynamic characteristics of bodies with rectangular cross section

    NASA Astrophysics Data System (ADS)

    Knoche, H. G.; Schamel, W.; Esch, H.; Schneider, W.

    Systematic wind tunnel tests for a series of missile bodies were conducted by varying cross section shape and body length in the subsonic Mach number range and up to high angles of attack. Tests with a body-wing and a body-tail configuration were performed in order to investigate the body-wing and body-tail interference for bodies of revolution and bodies with rectangular cross section. At a constant angle of attack, the boxlike body supplies far more normal force than the body of revolution with the same cross section area. The boxlike body shows strong coupling effects between the pitch, yaw and roll. The interference effect of the wing and body can be described well, in the case of boxlike bodies with wings in high or low wing positions, by the known slender body interference factors, assuming the width of the box to be the diameter of an equivalent, axially symetrical body.

  12. Recent advances in modeling fission cross sections over intermediate structures

    SciTech Connect

    Bouland, Olivier; Lynn, J. Eric; Talou, Patrick

    2009-01-01

    More accurate fission cross section calculations in presence of underlying intermediate structure are strongly desired. This paper recalls the common approximations used below the fission threshold and quantifies their impact. In particular, an exact expanded R-matrix Monte Carlo calculation of the intermediate structure, deeply mixed with the fluctuations of the class-I and II decay amplitudes, is shown. This paper also insists on the microscopic structure of the level densities as a function of the nucleus deformation and show preliminary neutron induced fission cross section calculations for {sup 239}Pu and {sup 240}Pu using newly calculated combinatorial level densities. Comparisons with recent evaluated and measured fission cross sections are made.

  13. Association Between Grading of Oral Submucous Fibrosis With Frequency and Consumption of Areca Nut and Its Derivatives in a Wide Age Group: A Multi-centric Cross Sectional Study From Karachi, Pakistan

    PubMed Central

    Hosein, Mervyn; Mohiuddin, Sidra; Fatima, Nazish

    2015-01-01

    Background: Oral submucous fibrosis (OSMF) is a chronic, premalignant condition of the oral mucosa and one of the commonest potentially malignant disorders amongst the Asian population. The objective of this study was to investigate the association of etiologic factors with: age, frequency, duration of consumption of areca nut and its derivatives, and the severity of clinical manifestations. Methods: A cross-sectional, multi centric study was conducted over 8 years on clinically diagnosed OSMF cases (n = 765) from both public and private tertiary care centers. Sample size was determined by World Health Organization sample size calculator. Consumption of areca nut in different forms, frequency of daily usage, years of chewing, degree of mouth opening and duration of the condition were recorded. Level of significance was kept at P ≤ 0.05. Results: A total of 765 patients of OSMF were examined, of whom 396 (51.8%) were male and 369 (48.2%) female with a mean age of 29.17 years. Mild OSMF was seen in 61 cases (8.0%), moderate OSMF in 353 (46.1%) and severe OSMF in 417 (54.5%) subjects. Areca nut and other derivatives were most frequently consumed and showed significant risk in the severity of OSMF (P ≤ 0.0001). Age of the sample and duration of chewing years were also significant (P = 0.012). Conclusions: The relative risk of OSMF increased with duration and frequency of areca nut consumption especially from an early age of onset. PMID:26473161

  14. Total cross section of electron scattering by fluorocarbon molecules

    NASA Astrophysics Data System (ADS)

    Yamada, T.; Ushiroda, S.; Kondo, Y.

    2008-12-01

    A compact linear electron transmission apparatus was used for the measurement of the total electron scattering cross section at 4-500 eV. Total cross sections of chlorofluorocarbon (CCl2F2), hydrochlorofluorocarbon (CHClF2), perfluoropropane (C3F8), perfluoro-n-pentane (C5F12), perfluoro-n-hexane (C6F14) and perfluoro-n-octane (C8F18) were obtained experimentally and compared with the values obtained from a theoretical calculation and semi-empirical model calculation.

  15. MINING INTEGRAL ACTINIDES CROSS SECTIONS FROM REACTOR DATA

    SciTech Connect

    PUIGH RJ

    2009-09-11

    The conclusions of this paper are: (1) mining of actinide cross-sections from reactor data is a viable and inexpensive approach to confirm burn-up codes; (2) extensive data for actinides in Hanford test data ({approx} 200 radiochemical analyses); (3) not only cross-section values and reaction rates can be established but also possible benchmark like data can be constructed to test and validate reactor and criticality safety codes such as SCALE/KENO or MCNPX; and (4) analysis along multiple transmutation paths can be evaluated to show consistency.

  16. Neutron removal cross section as a measure of neutron skin

    SciTech Connect

    Fang, D. Q.; Ma, Y. G.; Cai, X. Z.; Tian, W. D.; Wang, H. W.

    2010-04-15

    We study the relation between neutron removal cross section (sigma{sub -N}) and neutron skin thickness for finite neutron-rich nuclei using the statistical abrasion ablation model. Different sizes of neutron skin are obtained by adjusting the diffuseness parameter of neutrons in the Fermi distribution. It is demonstrated that there is a good linear correlation between sigma{sub -N} and the neutron skin thickness for neutron-rich nuclei. Further analysis suggests that the relative increase of neutron removal cross section could be used as a quantitative measure for neutron skin thickness in neutron-rich nuclei.

  17. SEU cross sections derived from a diffusion analysis

    SciTech Connect

    Edmonds, L.D.

    1996-12-01

    A simple theoretical prediction of single-event upset (SEU) cross section versus linear energy transfer (LET) is derived from a diffusion analysis, and the result is compared to some real device curves. It was found that at least some real device curves show two regimes. One regime (high-LET) is characterized by a very good fit to the theoretical prediction, and the other (low-LET) is characterized by a very bad fit. The existence of a high-LET regime provides additional credibility for the increasingly popular postulate that diffusion has an important effect on the shape of the cross-sectional curve.

  18. SU-E-I-43: Photoelectric Cross Section Revisited

    SciTech Connect

    Haga, A; Nakagawa, K; Kotoku, J; Horikawa, Y

    2015-06-15

    Purpose: The importance of the precision in photoelectric cross-section value increases for recent developed technology such as dual energy computed tomography, in which some reconstruction algorithms require the energy dependence of the photo-absorption in each material composition of human being. In this study, we revisited the photoelectric cross-section calculation by self-consistent relativistic Hartree-Fock (HF) atomic model and compared with that widely distributed as “XCOM database” in National Institute of Standards and Technology, which was evaluated with localdensity approximation for electron-exchange (Fock)z potential. Methods: The photoelectric cross section can be calculated with the electron wave functions in initial atomic state (bound electron) and final continuum state (photoelectron). These electron states were constructed based on the selfconsistent HF calculation, where the repulsive Coulomb potential from the electron charge distribution (Hartree term) and the electron exchange potential with full electromagnetic interaction (Fock term) were included for the electron-electron interaction. The photoelectric cross sections were evaluated for He (Z=2), Be (Z=4), C (Z=6), O (Z=8), and Ne (Z=10) in energy range of 10keV to 1MeV. The Result was compared with XCOM database. Results: The difference of the photoelectric cross section between the present calculation and XCOM database was 8% at a maximum (in 10keV for Be). The agreement tends to be better as the atomic number increases. The contribution from each atomic shell has a considerable discrepancy with XCOM database except for K-shell. However, because the photoelectric cross section arising from K-shell is dominant, the net photoelectric cross section was almost insensitive to the different handling in Fock potential. Conclusion: The photoelectric cross-section program has been developed based on the fully self-consistent relativistic HF atomic model. Due to small effect on the Fock

  19. Photon gluon fusion cross sections at HERA energy

    NASA Astrophysics Data System (ADS)

    Engelen, J. J.; Dejong, S. J.; Poletiek, M.; Vermaseren, J. A. M.

    1988-01-01

    Cross sections for heavy flavor production through photon gluon fusion in electron proton collisions are presented. The electron photon vertex is taken into account explicitly, and the Q sq of the exchanged photon ranges from nearly zero (almost real photon) to the kinematically allowed maximum. The QCD scale is set by the mass of the produced quarks. The formalism is also applicable to the production of light quarks as long as the invariant mass of the pair is sufficiently high, so cross sections for u anti-u, d anti-d, and s anti-s production are also given.

  20. Inclusive jet cross section measurement at D0

    SciTech Connect

    Voutilainen, M.; /Nebraska U. /Helsinki Inst. of Phys.

    2006-09-01

    We present a new preliminary measurement of the inclusive jet cross section in p{bar p} collisions based on a integrated luminosity of about 0.8 fb{sup -1}. The data were acquired using the D0 detector between 2002 and 2005. Jets are reconstructed using an iterative cone algorithm with radius R{sub cone} = 0.7. The inclusive jet cross section is presented as a function of transverse jet momentum and rapidity. Predictions from perturbative QCD in next-to-leading order, plus threshold corrections in 2-loop accuracy describe the shape in the transverse jet momentum.

  1. Uncertainty quantification in fission cross section measurements at LANSCE

    SciTech Connect

    Tovesson, F.

    2015-01-09

    Neutron-induced fission cross sections have been measured for several isotopes of uranium and plutonium at the Los Alamos Neutron Science Center (LANSCE) over a wide range of incident neutron energies. The total uncertainties in these measurements are in the range 3–5% above 100 keV of incident neutron energy, which results from uncertainties in the target, neutron source, and detector system. The individual sources of uncertainties are assumed to be uncorrelated, however correlation in the cross section across neutron energy bins are considered. The quantification of the uncertainty contributions will be described here.

  2. Neutron capture cross section standards for BNL 325, Fourth Edition

    SciTech Connect

    Holden, N.E.

    1981-01-01

    This report evaluates the experimental data and recommends values for the thermal neutron cross sections and resonance integrals for the neutron capture reactions: /sup 55/Mn(n,..gamma..), /sup 59/Co(n,..gamma..) and /sup 197/Au(n,..gamma..). The failure of lithium and boron as standards due to the natural variation of the absorption cross sections of these elements is discussed. The Westcott convention, which describes the neutron spectrum as a thermal Maxwellian distribution with an epithermal component, is also discussed.

  3. Light ray tracing through a leaf cross section

    NASA Technical Reports Server (NTRS)

    Kumar, R.; Silva, L. F.

    1973-01-01

    A light ray, incident at about 5 deg to the normal, is geometrically plotted through the drawing of the cross section of a soybean leaf using Fresnel's equations and Snell's law. The optical mediums of the leaf considered for ray tracing are: air, cell sap, chloroplast, and cell wall. The ray is also drawn through the same leaf cross section with cell wall and air as the only optical mediums. The values of the reflection and transmission found from the ray tracing tests agree closely with the experimental results obtained using a Beckman Dk-2A Spectroreflector.

  4. Light ray tracing through a leaf cross section

    NASA Technical Reports Server (NTRS)

    Kumar, R.; Silva, L.

    1973-01-01

    A light ray, incident at about 5 deg to the normal, is geometrically plotted through the drawing of the cross section of a soybean leaf using Fresnel's equations and Snell's law. The optical mediums of the leaf considered for ray tracing are air, cell sap, chloroplast, and cell wall. The above ray is also drawn through the same leaf cross section considering cell wall and air as the only optical mediums. The values of the reflection and transmission found from ray tracing agree closely with the experimental results obtained using a Beckman DK-2A spectroreflectometer.

  5. Photoabsorption cross sections of OH at 115-183 nm

    NASA Technical Reports Server (NTRS)

    Nee, J. B.; Lee, L. C.

    1984-01-01

    The absorption spectrum for OH was obtained in the 115-183 nm region. The OH radicals were produced by a pulse discharge of trace H2O in few torr of Ar. Absorption cross sections were obtained by calibration with absorption of the OH (X 2 Pi to A 2 Sigma +) transition. The features in the absorption spectrum are correlated with the excited states 1 2 Sigma -, D 2 Sigma -, 1 2 Delta, B 2 Sigma + and possibly others calculated by van Dishoeck, Langhoff, and Dalgarno. The measured cross sections are comparable with the calculated values.

  6. Fast-neutron scattering cross sections of elemental zirconium

    SciTech Connect

    Smith, A.B.; Guenther, P.T.

    1982-12-01

    Differential neturon-elastic-scattering cross sections of elemental zirconium are measured from 1.5 to 4.0 MeV at intervals of less than or equal to 200 keV. Inelastic-neutron-scattering cross sections corresponding to the excitation of levels at observed energies of: 914 +- 25, 1476 +- 37, 1787 +- 23, 2101 +- 26, 2221 +- 17, 2363 +- 14, 2791 +- 15 and 3101 +- 25 keV are determined. The experimental results are interpreted in terms of the optical-statistical model and are compared with corresponding quantities given in ENDF/B-V.

  7. Charge Influence on Mini Black Hole's Cross Section

    NASA Astrophysics Data System (ADS)

    Caraça, R. S.; Malheiro, M.

    In this work we study the electric charge effect on the cross section production of charged mini black holes (MBH) in accelerators. We analyze the charged MBH solution using the fat brane approximation in the context of the ADD model. The maximum charge-mass ratio condition for the existence of a horizon radius is discussed. We show that the electric charge causes a decrease in this radius and, consequently, in the cross section. This reduction is negligible for protons and light-ions but can be important for heavy-ions.

  8. Differential Cross Sections for Proton-Proton Elastic Scattering

    NASA Technical Reports Server (NTRS)

    Norman, Ryan B.; Dick, Frank; Norbury, John W.; Blattnig, Steve R.

    2009-01-01

    Proton-proton elastic scattering is investigated within the framework of the one pion exchange model in an attempt to model nucleon-nucleon interactions spanning the large range of energies important to cosmic ray shielding. A quantum field theoretic calculation is used to compute both differential and total cross sections. A scalar theory is then presented and compared to the one pion exchange model. The theoretical cross sections are compared to proton-proton scattering data to determine the validity of the models.

  9. Evaluation of the /sup 238/U neutron total cross section

    SciTech Connect

    Smith, A.; Poenitz, W.P.; Howerton, R.J.

    1982-12-01

    Experimental energy-averaged neutron total cross sections of /sup 238/U were evaluated from 0.044 to 20.0 MeV using regorous numerical methods. The evaluated results are presented together with the associated uncertainties and correlation matrix. They indicate that this energy-averaged neutron total cross section is known to better than 1% over wide energy regions. There are somwewhat larger uncertainties at low energies (e.g., less than or equal to 0.2 MeV), near 8 MeV and above 15 MeV. The present evaluation is compard with values given in ENDF/B-V.

  10. Uncertainty Quantification in Fission Cross Section Measurements at LANSCE

    SciTech Connect

    Tovesson, F.

    2015-01-15

    Neutron-induced fission cross sections have been measured for several isotopes of uranium and plutonium at the Los Alamos Neutron Science Center (LANSCE) over a wide range of incident neutron energies. The total uncertainties in these measurements are in the range 3–5% above 100 keV of incident neutron energy, which results from uncertainties in the target, neutron source, and detector system. The individual sources of uncertainties are assumed to be uncorrelated, however correlation in the cross section across neutron energy bins are considered. The quantification of the uncertainty contributions will be described here.

  11. Hadronic absorption cross sections of B{sub c}

    SciTech Connect

    Lodhi, M. A. K.; Akram, Faisal; Irfan, Shaheen

    2011-09-15

    The cross sections of B{sub c} absorption by {pi} mesons are calculated using a hadronic Lagrangian based on the SU(5) flavor symmetry. Calculated cross sections are found to be in the ranges 2-7 mb and 0.2-2 mb for the processes B{sub c}{sup +}{pi}{yields}DB and B{sub c}{sup +}{pi}{yields}D*B*, respectively, when the monopole form factor is included. These results could be useful in calculating the production rate of B{sub c} mesons in relativistic heavy ion collisions.

  12. Inelastic cross sections from gamma-ray measurements

    SciTech Connect

    Nelson, Ronald Owen

    2010-12-06

    Measurements of gamma rays following neutron induced reactions have been studied with the Germanium Array for Neutron-induced Excitations (GEANIE) at the Los Alamos Neutron Science Center (LANSCE) for many years. Gamma-ray excitation functions and coincidence studies provide insight into nuclear reaction mechanisms as well as expanding our knowledge of energy levels and gamma-rays. Samples studied with Ge detectors at LANSCE range from Be to Pu. Fe, Cr and Ti have been considered for use as reference cross sections. An overview of the measurements and efforts to create a reliable neutron-induced gamma-ray reference cross section will be presented.

  13. Review of Current and Future Neutrino Cross-Section Experiments

    SciTech Connect

    Schmitz, D.; /Fermilab

    2009-07-01

    There has been a surge of progress and published results in neutrino cross-section physics in recent years. In many cases, absolute differential cross-sections are being measured for the first time and can be compared to interaction models first developed decades ago. These measurements are important input for the next generation of accelerator-based neutrino oscillation experiments where precise understanding of both signal and background channels will be critical to the observation of sub-dominant oscillation effects. This paper discusses recent results from several experiments and describes new experiments currently under construction dedicated to making these measurements with unprecedented precision.

  14. Review of Current and Future Neutrino Cross-Section Experiments

    SciTech Connect

    Schmitz, D.

    2010-03-30

    There has been a surge of progress and published results in neutrino cross-section physics in recent years. In many cases, absolute differential cross-sections are being measured for the first time and can be compared to interaction models first developed decades ago. These measurements are important input for the next generation of accelerator-based neutrino oscillation experiments where precise understanding of both signal and background channels will be critical to the observation of sub-dominant oscillation effects. This paper discusses recent results from several experiments and describes new experiments currently under construction dedicated to making these measurements with unprecedented precision.

  15. Propagation of sound waves in tubes of noncircular cross section

    NASA Technical Reports Server (NTRS)

    Richards, W. B.

    1986-01-01

    Plane-acoustic-wave propagation in small tubes with a cross section in the shape of a flattened oval is described. Theoretical descriptions of a plane wave propagating in a tube with circular cross section and between a pair of infinite parallel plates, including viscous and thermal damping, are expressed in similar form. For a wide range of useful duct sizes, the propagation constant (whose real and imaginary parts are the amplitude attenuation rate and the wave number, respectively) is very nearly the same function of frequency for both cases if the radius of the circular tube is the same as the distance between the parallel plates. This suggests that either a circular-cross-section model or a flat-plate model can be used to calculate wave propagation in flat-oval tubing, or any other shape tubing, if its size is expressed in terms of an equivalent radius, given by g = 2 x (cross-sectional area)/(length of perimeter). Measurements of the frequency response of two sections of flat-oval tubing agree with calculations based on this idea. Flat-plate formulas are derived, the use of transmission-line matrices for calculations of plane waves in compound systems of ducts is described, and examples of computer programs written to carry out the calculations are shown.

  16. Writing Groups: Cross-Cultural Issues.

    ERIC Educational Resources Information Center

    Carson, Joan G.; Nelson, Gayle L.

    1994-01-01

    Writing groups, used in many English-as-a-Second-Language (ESL) composition classrooms, pose problems for some students from collectivistic cultures such as Japan and China. Suggested reasons are the individual benefit goal, the need for feedback rather than group harmony, and strained group dynamics. (Contains 41 references.) (Author/LB)

  17. Thermal Neutron Capture Cross Sections of the PalladiumIsotopes

    SciTech Connect

    Firestone, R.B.; Krticka, M.; McNabb, D.P.; Sleaford, B.; Agvaanluvsan, U.; Belgya, T.; Revay, Zs.

    2006-07-17

    Precise gamma-ray thermal neutron capture cross sectionshave been measured at the Budapest Reactor for all elements withZ=1-83,92 except for He and Pm. These measurements and additional datafrom the literature been compiled to generate the Evaluated Gamma-rayActivation File (EGAF), which is disseminated by LBNL and the IAEA. Thesedata are nearly complete for most isotopes with Z<20 so the totalradiative thermal neutron capture cross sections can be determineddirectly from the decay scheme. For light isotopes agreement with therecommended values is generally satisfactory although large discrepanciesexist for 11B, 12,13C, 15N, 28,30Si, 34S, 37Cl, and 40,41K. Neutroncapture decay data for heavier isotopes are typically incomplete due tothe contribution of unresolved continuum transitions so only partialradiative thermal neutron capture cross sections can be determined. Thecontribution of the continuum to theneutron capture decay scheme arisesfrom a large number of unresolved levels and transitions and can becalculated by assuming that the fluctuations in level densities andtransition probabilities are statistical. We have calculated thecontinuum contribution to neutron capture decay for the palladiumisotopes with the Monte Carlo code DICEBOX. These calculations werenormalized to the experimental cross sections deexciting low excitationlevels to determine the total radiative thermal neutron capture crosssection. The resulting palladium cross sections values were determinedwith a precision comparable to the recommended values even when only onegamma-ray cross section was measured. The calculated and experimentallevel feedings could also be compared to determine spin and parityassignments for low-lying levels.

  18. Radial Eigenmodes for a Toroidal Waveguide with Rectangular Cross Section

    SciTech Connect

    Rui Li

    2012-07-01

    In applying mode expansion to solve the CSR impedance for a section of toroidal vacuum chamber with rectangular cross section, we identify the eigenvalue problem for the radial eigenmodes which is different from that for cylindrical structures. In this paper, we present the general expressions of the radial eigenmodes, and discuss the properties of the eigenvalues on the basis of the Sturm-Liouville theory.

  19. 42. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

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

    42. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION 8, BUILDINGS NO. H-1 TO H-10 INCL., GRINDING, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (NashVille, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  20. 29. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

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

    29. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION 8, BUILDINGS NO. D-1 TO D-10 INCL., NITRATION, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  1. 35. Photograph of a line drawing. 'CROSS SECTION OF PART ...

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

    35. Photograph of a line drawing. 'CROSS SECTION OF PART III, SECTION 1, EQUIPMENT LAYOUT, BUILDINGS E-1 TO E-10 INCL., WASHING, MANUFACTURING AREA, PLANT 'B'.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  2. 30. Photograph of a line drawing. 'CROSS SECTION OF PART ...

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

    30. Photograph of a line drawing. 'CROSS SECTION OF PART III, SECTION 1, EQUIPMENT LAYOUT, BUILDINGS D-1 TO D-10 INCL., NITRATION, MANUFACTURING AREA, PLANT 'B'.' From U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  3. 34. Photograph of a line drawing. 'CROSS SECTION AND PLAN ...

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

    34. Photograph of a line drawing. 'CROSS SECTION AND PLAN LAYOUT OF PART I, SECTION B, BUILDINGS NO. E-1 TO E-10 INCL., WASHING, MANUFACTURING AREA, PLANT B AS OF 4-24-44.' From the U.S. Army Corps of Engineers. Industrial Facilities Inventory, Holston Ordnance Works, Kingsport, Tennessee. Plant B, Parts II, III. (Nashville, TN: Office of the District Engineer, 1944). - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  4. Emergency Department Crowding Disparity: a Nationwide Cross-Sectional Study

    PubMed Central

    2016-01-01

    In this study, we evaluated national differences in emergency department (ED) crowding to identify factors significantly associated with crowding in institutes and communities across Korea. This was a cross-sectional nationwide observational study using data abstracted from the National Emergency Department Information System (NEDIS). We calculated mean occupancy rates to quantify ED crowding status and divided EDs into three groups according to their occupancy rates (cutoffs: 0.5 and 1.0). Factors potentially related to ED crowding were collected from the NEDIS. We performed a multivariate regression analysis to identify variables significantly associated with ED crowding. A total of 120 EDs were included in the final analysis. Of these, 73 were categorized as 'low crowded' (LC, occupancy rate < 0.50), 37 as 'middle crowded' (MC, 0.50 ≤ occupancy rate < 1.00), 10 EDs as 'high crowded' (HC, 1.00 ≤ occupancy rate). The mean ED occupancy rate varied widely, from 0.06 to 2.33. The median value was 0.39 with interquartile ranges (IQRs) from 0.20 to 0.71. Multivariate analysis revealed that after adjustment, ED crowding was significantly associated with the number of visits, percentage of patients referred, number of nurses, and ED disposition. This nationwide study observed significant variety in ED crowding. Several input, throughput, and output factors were associated with crowding. PMID:27478347

  5. Respiratory hazards in hard metal workers: a cross sectional study.

    PubMed Central

    Meyer-Bisch, C; Pham, Q T; Mur, J M; Massin, N; Moulin, J J; Teculescu, D; Carton, B; Pierre, F; Baruthio, F

    1989-01-01

    A cross sectional study was conducted on 513 employees at three hard metal plants: 425 exposed workers (351 men, 74 women) and 88 controls (69 men, 19 women). Cough and sputum were more frequent in workers engaged in "soft powder" and presintering workshops compared with controls (12.5% and 16.5% v 3.5%). Spirometric abnormalities were more frequent among women in sintering and finishing workshops compared with control women (56.8% v 23.8%) and abnormalities of carbon monoxide test were more frequent in exposed groups than in controls; this difference was more pronounced in women (31.4% v 5.6%) than in men (18.5% v 13%). No significant correlation was observed between duration of exposure and age adjusted lung function tests. Slight abnormalities of chest radiographs (0/1, 1/1 according to ILO classification) were more frequent in exposed men than controls (12.8% v 1.9%) and mostly in soft powder workers. In subjects with abnormal chest radiographs FVC, FEV1 and carbon monoxide indices (fractional uptake of CO or CO transfer index or both) were lower compared with those with normal chest radiographs. Although relatively mild, the clinical, radiological, and functional abnormalities uncovered call for a regular supervision of workers exposed to hard metal dust. PMID:2787666

  6. Emergency Department Crowding Disparity: a Nationwide Cross-Sectional Study.

    PubMed

    Cha, Won Chul; Ahn, Ki Ok; Shin, Sang Do; Park, Jeong Ho; Cho, Jin Sung

    2016-08-01

    In this study, we evaluated national differences in emergency department (ED) crowding to identify factors significantly associated with crowding in institutes and communities across Korea. This was a cross-sectional nationwide observational study using data abstracted from the National Emergency Department Information System (NEDIS). We calculated mean occupancy rates to quantify ED crowding status and divided EDs into three groups according to their occupancy rates (cutoffs: 0.5 and 1.0). Factors potentially related to ED crowding were collected from the NEDIS. We performed a multivariate regression analysis to identify variables significantly associated with ED crowding. A total of 120 EDs were included in the final analysis. Of these, 73 were categorized as 'low crowded' (LC, occupancy rate < 0.50), 37 as 'middle crowded' (MC, 0.50 ≤ occupancy rate < 1.00), 10 EDs as 'high crowded' (HC, 1.00 ≤ occupancy rate). The mean ED occupancy rate varied widely, from 0.06 to 2.33. The median value was 0.39 with interquartile ranges (IQRs) from 0.20 to 0.71. Multivariate analysis revealed that after adjustment, ED crowding was significantly associated with the number of visits, percentage of patients referred, number of nurses, and ED disposition. This nationwide study observed significant variety in ED crowding. Several input, throughput, and output factors were associated with crowding. PMID:27478347

  7. Daily practice management of myelodysplastic syndromes in France: data from 907 patients in a one-week cross-sectional study by the Groupe Francophone des Myélodysplasies

    PubMed Central

    Kelaidi, Charikleia; Stamatoullas, Aspasia; Beyne-Rauzy, Odile; Raffoux, Emmanuel; Quesnel, Bruno; Guerci, Agnes; Dreyfus, François; Brechignac, Sabine; Berthou, Christian; Prebet, Thomas; Hicheri, Yosr; Hacini, Maya; Delaunay, Jacques; Gourin, Marie-Pierre; Camo, Jean-Marie; Zerazhi, Hacene; Taksin, Anne-Laure; Legros, Laurence; Choufi, Bachra; Fenaux, Pierre

    2010-01-01

    Background There is little published information on the everyday clinical management of myelodysplastic syndromes in real world practice. Design and Methods We conducted a cross-sectional study of all patients with myelodysplastic syndromes attending 74 French centers in a 1-week period for inpatient admission, day-hospital care or outpatient visits. Results Nine hundred and seven patients were included; 67.3% had lower-risk myelodysplastic syndromes (International Prognostic Scoring System: low or intermediate-1). Karyotype had been analyzed in 82.5% of the cases and was more often of intermediate or poor risk in patients under 65 years old compared with those who were older. Red blood cell transfusions accounted for as many as 31.4% of the admissions. Endogenous erythropoietin level was less than 500 IU/L in 88% of the patients tested. Erythroid stimulating agents had been or were being used in 36.8% of the lower risk patients, iron chelation in 31% of lower risk patients requiring red blood cell transfusions and lenalidomide in 41% of lower risk patients with del 5q. High-dose chemotherapy, hypomethylating agents, low dose cytarabine and allogeneic stem cell transplantation had been or were being used in 14.8%, 31.1%, 8.8% and 5.1%, respectively, of higher-risk patients. Conclusions Karyotype is now assessed in most patients with myelodysplastic syndromes, and patients under 65 years old may have more aggressive disease. Apart from erythroid-stimulating agents and, in higher-risk myelodysplastic syndromes, hypomethylating agents, specific treatments are used in a minority of patients with myelodysplastic syndromes and red blood cell transfusions still represent the major reason for hospital admission. PMID:20015890

  8. Total Electron-Impact Ionization Cross-Sections of CFx and NFx (x = 1 - 3)

    NASA Technical Reports Server (NTRS)

    Huo, Winifred M.; Tarnovsky, Vladimir; Becker, Kurt H.; Kwak, Dochan (Technical Monitor)

    2001-01-01

    The discrepancy between experimental and theoretical total electron-impact ionization cross sections for a group of fluorides, CFx, and NFx, (x = 1 - 3), is attributed to the inadequacies in previous theoretical models. Cross-sections calculated using a recently developed siBED (simulation Binary-Encounter-Dipole) model that takes into account the shielding of the long-range dipole potential between the scattering electron and target are in agreement with experimentation. The present study also carefully reanalyzed the previously reported experimental data to account for the possibility of incomplete collection of fragment ions and the presence of ion-pair formation channels. For NF3, our experimental and theoretical cross-sections compare well with the total ionization cross-sections recently reported by Haaland et al. in the region below dication formation.

  9. Transport model based on three-dimensional cross-section generation for TRIGA core analysis

    SciTech Connect

    Kriangchaiporn, N.; Ivanov, K.; Haghighat, A.; Sears, C. F.

    2006-07-01

    The development of a three-dimensional (3-D) transport model for TRIGA core analysis based on the discrete ordinates (S{sub n}) method has been conducted. The effective fine- and broad- group structures for the TRIGA cross-section libraries were selected based on CPXSD (Contribution and Point-wise Cross-Section Driven) methodology. Different 3-D pin/core configurations are used to verify and validate the selected effective group structures. Thirteen-group structure was finally selected to be used for core analysis. The results agree with continuous energy cross-section Monte Carlo calculations for eigenvalues and normalized pin power distributions, which are used as a reference in this research. (authors)

  10. 55. CROSS SECTION OF POWER HOUSE, EXHIBIT L, SANTA ANA ...

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

    55. CROSS SECTION OF POWER HOUSE, EXHIBIT L, SANTA ANA RIVER NO. 1 PROJECT, APR. 30, 1945. SCE drawing no. 523199 (sheet no. 9, for filing with Federal Power Commission). - Santa Ana River Hydroelectric System, SAR-1 Powerhouse, Redlands, San Bernardino County, CA

  11. Cross section measurements via residual nuclear decays: Analysis methods

    SciTech Connect

    Zhou Fengqun; Gao Lei; Li Kuohu; Song Yueli; Zhang Fang; Kong Xiangzhong; Luo Junhua

    2009-11-15

    We develop an approach to calculating the pure cross section of the ground state of artificial radioactive nuclides that subtracts the effect of an excited state on the ground state. We apply a formalism to obtaining pure cross sections by subtracting the effect of excited states in the reactions {sup 122}Te(n,2n){sup 121}Te{sup g} and {sup 128}Te(n,2n){sup 127}Te{sup g}, induced by neutrons of about 14 MeV. The cross sections are measured by an activation relative to the {sup 93}Nb(n,2n){sup 92}Nb{sup m} reaction and are compared with results that take into account the effect of the excited state. Measurements are carried out by {gamma} detection using a coaxial high-purity germanium (HPGe) detector. As samples, spectroscopically pure Te powder is used. The fast neutrons are produced by the {sup 3}H(d,n){sup 4}He reaction. The neutron energies in these measurements are determined using the method of cross-section ratios between the {sup 90}Zr(n,2n){sup 89}Zr{sup m+g} and {sup 93}Nb(n,2n){sup 92}Nb{sup m} reactions.

  12. 44. CROSS SECTION OF GRAND CANAL (not to scale, but ...

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

    44. CROSS SECTION OF GRAND CANAL (not to scale, but representative of all six canals) Plan Sheet D-29976, Venice Canals Rehabilitation, Sheet No. 7 of 26 (delineated by T. Wu and E. Lee, March 1991) - Venice Canals, Community of Venice, Los Angeles, Los Angeles County, CA

  13. UV-visible absorption cross sections of nitrous acid

    NASA Astrophysics Data System (ADS)

    Stutz, J.; Kim, E. S.; Platt, U.; Bruno, P.; Perrino, C.; Febo, A.

    2000-06-01

    Nitrous acid, HONO, is a source of OH radicals in the polluted atmosphere. Although the atmospheric chemistry of HONO is qualitatively understood, not much quantitative information exists. The magnitude of the OH production by HONO photolysis depends on the spectrum of its absorption cross sections; therefore the knowledge of σ'HONO(λ) is essential. The spectrum of the differential cross sections σ'HONO(λ) is needed to detect HONO in the atmosphere by differential optical absorption spectroscopy (DOAS). Here we present measurements of the HONO UV-visible absorption cross sections with a spectral resolution better than 0.1 nm and a high signal-to-noise ratio. The maximum value of the absorption cross sections is σHONO (354 nm) = (5.19±0.26) × 10-19 cm2 and agrees well with literature data. Nevertheless, calculations based on data from this work and on literature data reveal that an uncertainty of ˜15% remains for the HONO photolysis rates. The new σHONO(λ) has been employed in DOAS measurements in Milan, Italy.

  14. 35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December ...

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

    35. 'Firing Pier, Cross Sections, Looking South,' submitted 29 December 1941 by John Brackett, Consulting Engineer, to Public Works Department, Bureau of Yards & Docks. PW Drawing 3874-46, Y&D Drawing 190848. Scale 1/8' = 1'. - Naval Torpedo Station, Firing Pier, North end of Gould Island in Narragansett Bay, Newport, Newport County, RI

  15. 7. Photograph of a line drawing. SHEET 7, CROSS SECTION ...

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

    7. Photograph of a line drawing. SHEET 7, CROSS SECTION ON LINE CC AND DD; 9-16-1940. Assembly Building for Tank Plant for the Chrysler Corporation, Macomb County, Michigan. Delineator: E.B. - Detroit Arsenal, 6501 East Eleven Mile Road, Warren, Macomb County, MI

  16. Commentary: Mediation Analysis, Causal Process, and Cross-Sectional Data

    ERIC Educational Resources Information Center

    Shrout, Patrick E.

    2011-01-01

    Maxwell, Cole, and Mitchell (2011) extended the work of Maxwell and Cole (2007), which raised important questions about whether mediation analyses based on cross-sectional data can shed light on longitudinal mediation process. The latest article considers longitudinal processes that can only be partially explained by an intervening variable, and…

  17. C+C Fusion Cross Sections Measurements for Nuclear Astrophysics

    DOE PAGESBeta

    Almaraz-Calderon, S.; Carnelli, P. F. F.; Rehm, K. E.; Albers, M.; Alcorta, M.; Bertone, P. F.; Digiovine, B.; Esbensen, H.; Fernandez Niello, J. O.; Henderson, D.; et al

    2015-06-02

    Total fusion cross section of carbon isotopes were obtained using the newly developed MUSIC detector. MUSIC is a highly efficient, active target-detector system designed to measure fusion excitation functions with radioactive beams. The present measurements are relevant for understanding x-ray superbursts. The results of the first MUSIC campaign as well as the astrophysical implications are presented in this work.

  18. Stellar neutron capture cross sections of the Lu isotopes

    SciTech Connect

    Wisshak, K.; Voss, F.; Kaeppeler, F.; Kazakov, L.

    2006-01-15

    The neutron capture cross sections of {sup 175}Lu and {sup 176}Lu have been measured in the energy range 3-225 keV at the Karlsruhe 3.7 MV Van de Graaff accelerator. Neutrons were produced via the {sup 7}Li(p,n){sup 7}Be reaction by bombarding metallic Li targets with a pulsed proton beam, and capture events were registered with the Karlsruhe 4{pi} barium fluoride detector. The cross sections were determined relative to the gold standard using isotopically enriched as well as natural lutetium oxide samples. Overall uncertainties of {approx}1% could be achieved in the final cross section ratios to the gold standard, about a factor of 5 smaller than in previous works. Maxwellian averaged neutron capture cross sections were calculated for thermal energies between kT = 8 and 100 keV. These values are systematically larger by {approx}7% than those reported in recent evaluations. These results are of crucial importance for the assessment of the s-process branchings at A 175/176.

  19. Uptake of atmospheric molecules by ice nanoparticles: Pickup cross sections

    NASA Astrophysics Data System (ADS)

    Lengyel, J.; Kočišek, J.; Poterya, V.; Pysanenko, A.; Svrčková, P.; Fárník, M.; Zaouris, D. K.; Fedor, J.

    2012-07-01

    Uptake of several atmospheric molecules on free ice nanoparticles was investigated. Typical examples were chosen: water, methane, NOx species (NO, NO2), hydrogen halides (HCl, HBr), and volatile organic compounds (CH3OH, CH3CH2OH). The cross sections for pickup of these molecules on ice nanoparticles (H2O)N with the mean size of bar{N} ≈ 260 (diameter ˜2.3 nm) were measured in a molecular beam experiment. These cross sections were determined from the cluster beam velocity decrease due to the momentum transfer during the pickup process. For water molecules molecular dynamics simulations were performed to learn the details of the pickup process. The experimental results for water are in good agreement with the simulations. The pickup cross sections of ice particles of several nanometers in diameter can be more than 3 times larger than the geometrical cross sections of these particles. This can have significant consequences in modelling of atmospheric ice nanoparticles, e.g., their growth.

  20. RZ calculations for self shielded multigroup cross sections

    SciTech Connect

    Li, M.; Sanchez, R.; Zmijarevic, I.; Stankovski, Z.

    2006-07-01

    A collision probability method has been implemented for RZ geometries. The method accounts for white albedo, specular and translation boundary condition on the top and bottom surfaces of the geometry and for a white albedo condition on the outer radial surface. We have applied the RZ CP method to the calculation of multigroup self shielded cross sections for Gadolinia absorbers in BWRs. (authors)

  1. Skin Diseases: Cross-section of human skin

    MedlinePlus

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  2. 11. Photograph of a line drawing. 'CROSS SECTION OF GAS ...

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

    11. Photograph of a line drawing. 'CROSS SECTION OF GAS PRODUCER.' From George R. Cooper (Wilputte Corporation). 'Operating Overview of a Producer Gas Plant (12 Machines) at Kingsport, Tennessee.' Presented at the Fifth Annual International Conference on Coal Gasification, Liquefaction and Conversion to Electricity. University of Pittsburgh, August 2, 1978. - Holston Army Ammunition Plant, Producer Gas Plant, Kingsport, Sullivan County, TN

  3. Diffractive dijet cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Breitweg, J.; Derrick, M.; Krakauer, D.; Magill, S.; Mikunas, D.; Musgrave, B.; Repond, J.; Stanek, R.; Talaga, R. L.; Yoshida, R.; Zhang, H.; Mattingly, M. C. K.; Anselmo, F.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Romeo, G. Cara; Castellini, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Coppola, N.; Corradi, M.; de Pasquale, S.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Polini, A.; Sartorelli, G.; Garcia, Y. Zamora; Zichichi, A.; Amelung, C.; Bornheim, A.; Brock, I.; Coböken, K.; Crittenden, J.; Deffner, R.; Eckert, M.; Grothe, M.; Hartmann, H.; Heinloth, K.; Heinz, L.; Hilger, E.; Jakob, H.-P.; Kappes, A.; Katz, U. F.; Kerger, R.; Paul, E.; Pfeiffer, M.; Stamm, J.; Wieber, H.; Bailey, D. S.; Campbell-Robson, S.; Cottingham, W. N.; Foster, B.; Hall-Wilton, R.; Heath, G. P.; Heath, H. F.; McFall, J. D.; Piccioni, D.; Roff, D. G.; Tapper, R. J.; Ayad, R.; Capua, M.; Iannotti, L.; Schioppa, M.; Susinno, G.; Kim, J. Y.; Lee, J. H.; Lim, I. T.; Pac, M. Y.; Caldwell, A.; Cartiglia, N.; Jing, Z.; Liu, W.; Mellado, B.; Parsons, J. A.; Ritz, S.; Sampson, S.; Sciulli, F.; Straub, P. B.; Zhu, Q.; Borzemski, P.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Klimek, K.; Przybycień, M. B.; Zawiejski, L.; Adamczyk, L.; Bednarek, B.; Bukowy, M.; Czermak, A. M.; Jeleń, K.; Kisielewska, D.; Kowalski, T.; Przybycień, M.; Rulikowska-Zarbska, E.; Suszycki, L.; Zajc, J.; Duliński, Z.; Kotański, A.; Abbiendi, G.; Bauerdick, L. A. T.; Behrens, U.; Beier, H.; Bienlein, J. K.; Desler, K.; Drews, G.; Fricke, U.; Gialas, I.; Goebel, F.; Göttlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hasell, D.; Hebbel, K.; Johnson, K. F.; Kasemann, M.; Koch, W.; Kötz, U.; Kowalski, H.; Lindemann, L.; Löhr, B.; Milewski, J.; Milite, M.; Monteiro, T.; Ng, J. S. T.; Notz, D.; Park, I. H.; Pellegrino, A.; Pelucchi, F.; Piotrzkowski, K.; Rohde, M.; Roldán, J.; Ryan, J. J.; Savin, A. A.; Schneekloth, U.; Schwarzer, O.; Selonke, F.; Stonjek, S.; Surrow, B.; Tassi, E.; Westphal, D.; Wolf, G.; Wollmer, U.; Youngman, C.; Zeuner, W.; Burow, B. D.; Coldewey, C.; Grabosch, H. J.; Meyer, A.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P.; Maccarrone, G.; Votano, L.; Bamberger, A.; Eisenhardt, S.; Markun, P.; Raach, H.; Trefzger, T.; Wölfle, S.; Bromley, J. T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; MacDonald, N.; Saxon, D. H.; Sinclair, L. E.; Skillicorn, I. O.; Strickland, E.; Waugh, R.; Bohnet, I.; Gendner, N.; Holm, U.; Meyer-Larsen, A.; Salehi, H.; Wick, K.; Garfagnini, A.; Gladilin, L. K.; Horstmann, D.; Kçira, D.; Klanner, R.; Lohrmann, E.; Poelz, G.; Schott, W.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Cole, J. E.; Howell, G.; Lamberti, L.; Long, K. R.; Miller, D. B.; Pavel, N.; Prinias, A.; Sedgbeer, J. K.; Sideris, D.; Walker, R.; Mallik, U.; Wang, S. M.; Wu, J. T.; Cloth, P.; Filges, D.; Fleck, J. I.; Ishii, T.; Kuze, M.; Suzuki, I.; Tokushuku, K.; Yamada, S.; Yamauchi, K.; Yamazaki, Y.; Hong, S. J.; Lee, S. B.; Nam, S. W.; Park, S. K.; Barreiro, F.; Fernández, J. P.; García, G.; Glasman, C.; Hernández, J. M.; Hervás, L.; Labarga, L.; Martínez, M.; Peso, J. Del; Puga, J.; Terrón, J.; Trocóniz, J. F. De; Corriveau, F.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Murray, W. N.; Ochs, A.; Riveline, M.; Stairs, D. G.; St-Laurent, M.; Ullmann, R.; Tsurugai, T.; Bashkirov, V.; Dolgoshein, B. A.; Stifutkin, A.; Bashindzhagyan, G. L.; Ermolov, P. F.; Golubkov, Yu. A.; Khein, L. A.; Korotkova, N. A.; Korzhavina, I. A.; Kuzinin, V. A.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Solomin, A. N.; Zotkin, S. A.; Bokel, C.; Botje, M.; Brümmer, N.; Engelen, J.; Koffeman, E.; Kooijman, P.; van Sighem, A.; Tiecke, H.; Tuning, N.; Verkerke, W.; Vossebeld, J.; Wiggers, L.; Wolf, E. De; Acosta, D.; Bylsma, B.; Durkin, L. S.; Gilmore, J.; Ginsburg, C. M.; Kim, C. L.; Ling, T. Y.; Nylander, P.; Romanowski, T. A.; Blaikley, H. E.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Edmonds, J. K.; Große-Knetter, J.; Harnew, N.; Nath, C.; Noyes, V. A.; Quadt, A.; Ruske, O.; Tickner, J. R.; Walczak, R.; Waters, D. S.; Bertolin, A.; Brugnera, R.; Carlin, R.; Corso, F. Dal; Dosselli, U.; Limentani, S.; Morandin, M.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Bulmahn, J.; Oh, B. Y.; Okrasiński, J. R.; Toothacker, W. S.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Raso, M.; Hart, J. C.; McCubbin, N. A.; Shah, T. P.; Epperson, D.; Heusch, C.; Rahn, J. T.; Sadrozinski, H. F.-W.; Seiden, A.; Wichmann, R.; Williams, D. C.; Abramowicz, H.; Briskin, G.; Dagan, S.; Kananov, S.; Levy, A.; Abe, T.; Fusayasu, T.; Inuzuka, M.; Nagano, K.; Umemori, K.; Yamashita, T.; Hamatsu, R.; Hirose, T.; Homma, K.; Kitamura, S.; Matsushita, T.; Arneodo, M.; Cirio, R.; Costa, M.; Ferrero, M. I.; Maselli, S.; Monaco, V.; Peroni, C.; Petrucci, M. C.; Ruspa, M.; Sacchi, R.; Solano, A.; Staiano, A.; Dardo, M.; Bailey, D. C.; Fagerstroem, C.-P.; Galea, R.; Hartner, G. F.; Joo, K. K.; Levman, G. M.; Martin, J. F.; Orr, R. S.; Polenz, S.; Sabetfakhri, A.; Simmons, D.; Teuscher, R. J.; Butterworth, J. M.; Catterall, C. D.; Hayes, M. E.; Jones, T. W.; Lane, J. B.; Saunders, R. L.; Sutton, M. R.; Wing, M.; Ciborowski, J.; Grzelak, G.; Kasprzak, M.; Nowak, R. J.; Pawlak, J. M.; Pawlak, R.; Tymieniecka, T.; Wróblewski, A. K.; Zakrzewski, J. A.; Zarnecki, A. F.; Adamus, M.; Deppe, O.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Badgett, W. F.; Chapin, D.; Cross, R.; Dasu, S.; Foudas, C.; Loveless, R. J.; Mattingly, S.; Reeder, D. D.; Smith, W. H.; Vaiciulis, A.; Wodarczyk, M.; Deshpande, A.; Dhawan, S.; Hughes, V. W.; Bhadra, S.; Frisken, W. R.; Khakzad, M.; Schmidke, W. B.

    1998-08-01

    Differential dijet cross sections have been measured with the ZEUS detector for photoproduction events in which the hadronic final state containing the jets is separated with respect to the outgoing proton direction by a large rapidity gap. The cross section has been measured as a function of the fraction of the photon (ϰγ OBS) and pomeron (β OBS) momentum participating in the production of the dijet system. The observed ϰγ OBS dependence shows evidence for the presence of a resolved- as well as a direct-photon component. The measured cross section da/dβ OBS increases as β OBS increases indicating that there is a sizeable contribution to dijet production from those events in which a large fraction of the pomeron momentum participates in the hard scattering. These cross sections and the ZEUS measurements of the diffractive structure function can be described by calculations based on parton densities in the pomeron which evolve according to the QCD evolution equations and include a substantial hard momentum component of gluons in the pomeron.

  4. High-mass dijet cross sections in photoproduction at HERA

    NASA Astrophysics Data System (ADS)

    Chekanov, S.; Derrick, M.; Krakauer, D.; Magill, S.; Musgrave, B.; Pellegrino, A.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; De Pasquale, S.; Giusti, P.; Iacobucci, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Palmonari, F.; Pesci, A.; Sartorelli, G.; Zichichi, A.; Aghuzumtsyan, G.; Bartsch, D.; Brock, I.; Crittenden, J.; Goers, S.; Hartmann, H.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kappes, A.; Katz, U. F.; Kerger, R.; Kind, O.; Paul, E.; Rautenberg, J.; Renner, R.; Schnurbusch, H.; Stifutkin, A.; Tandler, J.; Voss, K. C.; Weber, A.; Wessoleck, H.; Bailey, D. S.; Brook, N. H.; Cole, J. E.; Foster, B.; Heath, G. P.; Heath, H. F.; Robins, S.; Rodrigues, E.; Scott, J.; Tapper, R. J.; Wing, M.; Capua, M.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Jeoung, H. Y.; Kim, J. Y.; Lee, J. H.; Lim, I. T.; Ma, K. J.; Pac, M. Y.; Caldwell, A.; Helbich, M.; Liu, X.; Mellado, B.; Paganis, S.; Schmidke, W. B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Olkiewicz, K.; Przybycień, M. B.; Stopa, P.; Zawiejski, L.; Bednarek, B.; Grabowska-Bold, I.; Jeleń, K.; Kisielewska, D.; Kowal, A. M.; Kowal, M.; Kowalski, T.; Mindur, B.; Przybycień, M.; Rulikowska-Zarȩbska, E.; Suszycki, L.; Szuba, D.; Szuba, J.; Kotański, A.; Słomiński, W.; Bauerdick, L. A. T.; Behrens, U.; Borras, K.; Chiochia, V.; Dannheim, D.; Desler, K.; Drews, G.; Fourletova, J.; Fox-Murphy, A.; Fricke, U.; Geiser, A.; Goebel, F.; Göttlicher, P.; Graciani, R.; Haas, T.; Hain, W.; Hartner, G. F.; Hillert, S.; Kötz, U.; Kowalski, H.; Labes, H.; Lelas, D.; Löhr, B.; Mankel, R.; Martens, J.; Martínez, M.; Moritz, M.; Notz, D.; Petrucci, M. C.; Polini, A.; Schneekloth, U.; Selonke, F.; Stonjek, S.; Surrow, B.; Whitmore, J. J.; Wichmann, R.; Wolf, G.; Youngman, C.; Zeuner, W.; Coldewey, C.; Lopez-Duran Viani, A.; Meyer, A.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Genta, C.; Pelfer, P. G.; Bamberger, A.; Benen, A.; Coppola, N.; Markun, P.; Raach, H.; Wölfle, S.; Bell, M.; Bussey, P. J.; Doyle, A. T.; Glasman, C.; Hanlon, S.; Lee, S. W.; Lupi, A.; McCance, G. J.; Saxon, D. H.; Skillicorn, I. O.; Bodmann, B.; Holm, U.; Salehi, H.; Wick, K.; Ziegler, A.; Ziegler, Ar.; Carli, T.; Gialas, I.; Klimek, K.; Lohrmann, E.; Milite, M.; Collins-Tooth, C.; Foudas, C.; Gonçalo, R.; Long, K. R.; Metlica, F.; Miller, D. B.; Tapper, A. D.; Walker, R.; Cloth, P.; Filges, D.; Kuze, M.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Ahn, S. H.; Lee, S. B.; Park, S. K.; Lim, H.; Son, D.; Barreiro, F.; García, G.; González, O.; Labarga, L.; del Peso, J.; Redondo, I.; Terrón, J.; Vázquez, M.; Barbi, M.; Bertolin, A.; Corriveau, F.; Ochs, A.; Padhi, S.; Stairs, D. G.; St-Laurent, M.; Tsurugai, T.; Antonov, A.; Bashkirov, V.; Danilov, P.; Dolgoshein, B. A.; Gladkov, D.; Sosnovtsev, V.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Golubkov, Yu. A.; Katkov, I. I.; Khein, L. A.; Korotkova, N. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Solomin, A. N.; Vlasov, N. N.; Zotkin, S. A.; Bokel, C.; Engelen, J.; Grijpink, S.; Koffeman, E.; Kooijman, P.; Maddox, E.; Schagen, S.; Tassi, E.; Tiecke, H.; Tuning, N.; Velthuis, J. J.; Wiggers, L.; de Wolf, E.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Gilmore, J.; Ginsburg, C. M.; Kim, C. L.; Ling, T. Y.; Boogert, S.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Ferrando, J.; Matsushita, T.; Rigby, M.; Ruske, O.; Sutton, M. R.; Walczak, R.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Parenti, A.; Posocco, M.; Stanco, L.; Turcato, M.; Adamczyk, L.; Oh, B. Y.; Saull, P. R. B.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cormack, C.; Hart, J. C.; McCubbin, N. A.; Heusch, C.; Park, I. H.; Pavel, N.; Abramowicz, H.; Dagan, S.; Gabareen, A.; Kananov, S.; Kreisel, A.; Levy, A.; Abe, T.; Fusayasu, T.; Kohno, T.; Umemori, K.; Yamashita, T.; Hamatsu, R.; Hirose, T.; Inuzuka, M.; Kitamura, S.; Matsuzawa, K.; Nishimura, T.; Arneodo, M.; Cartiglia, N.; Cirio, R.; Costa, M.; Ferrero, M. I.; Maselli, S.; Monaco, V.; Peroni, C.; Ruspa, M.; Sacchi, R.; Solano, A.; Staiano, A.; Galea, R.; Koop, T.; Levman, G. M.; Martin, J. F.; Mirea, A.; Sabetfakhri, A.; Butterworth, J. M.; Gwenlan, C.; Hall-Wilton, R.; Hayes, M. E.; Heaphy, E. A.; Jones, T. W.; Lane, J. B.; Lightwood, M. S.; West, B. J.; Ciborowski, J.; Ciesielski, R.; Grzelak, G.; Nowak, R. J.; Pawlak, J. M.; Smalska, B.; Sztuk, J.; Tymieniecka, T.; Ukleja, A.; Ukleja, J.; Zakrzewski, J. A.; Żarnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Gladilin, L. K.; Hochman, D.; Karshon, U.; Breitweg, J.; Chapin, D.; Cross, R.; Kçira, D.; Lammers, S.; Reeder, D. D.; Savin, A. A.; Smith, W. H.; Deshpande, A.; Dhawan, S.; Hughes, V. W.; Straub, P. B.; Bhadra, S.; Catterall, C. D.; Fourletov, S.; Menary, S.; Soares, M.; Standage, J.; ZEUS Collaboration

    2002-04-01

    Dijet differential cross sections for the reaction e+p→e++ jet + jet + X in the photoproduction regime have been measured with the ZEUS detector at HERA using an integrated luminosity of 42.7 pb-1. The cross sections are given for photon-proton centre-of-mass energies in the range 134cross sections as a function of the dijet mass, Mjj, and of the dijet angular variables have been measured for 47cross section for Z0 photoproduction of σe+p→e+Z0X<5.9 pb. Upper limits on the photoproduction of new heavy resonances decaying into two jets are also presented for masses in the range between 60 GeV and 155 GeV.

  5. Exponentiation of eikonal cross sections in nonabelian gauge theories

    NASA Astrophysics Data System (ADS)

    Gatheral, J. G. M.

    1983-12-01

    A theorem is presented which generalises the well-known exponentiation property of eikonal cross sections in abelian gauge theories to the nonabelian case. Address after September 1, 1983: Bank of America, 25 Cannon Street, London EC4P 4HN, UK.

  6. Service building. Cross section thru dry dock nos. 4 & ...

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

    Service building. Cross section thru dry dock nos. 4 & 5 showing service bldg & 20-75-150 ton cranes (dry dock associates, May 23, 1941). In files of Cushman & Wakefield, building no. 501, Philadelphia Naval Business Center. - Naval Base Philadelphia-Philadelphia Naval Shipyard, Service Building, Dry Docks No. 4 & 5, League Island, Philadelphia, Philadelphia County, PA

  7. Radar cross sections of standard and complex shape targets

    NASA Technical Reports Server (NTRS)

    Sohel, M. S.

    1974-01-01

    The theoretical, analytical, and experimental results are described for radar cross sections (RCS) of different-shaped targets. Various techniques for predicting RCS are given, and RCS of finite standard targets are presented. Techniques used to predict the RCS of complex targets are made, and the RCS complex shapes are provided.

  8. Accurate momentum transfer cross section for the attractive Yukawa potential

    SciTech Connect

    Khrapak, S. A.

    2014-04-15

    Accurate expression for the momentum transfer cross section for the attractive Yukawa potential is proposed. This simple analytic expression agrees with the numerical results better than to within ±2% in the regime relevant for ion-particle collisions in complex (dusty) plasmas.

  9. Medium Modified Nucleon-Nucleon Cross Sections in a Nucleus

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Cucinotta, F. A.; Wilson, J. W.

    1999-01-01

    A simple reliable formalism is presented for obtaining nucleon-nucleon cross sections within a nucleus in nuclear collisions for a given projectile and target nucleus combination at a given energy for use in transport, Monte Carlo and other calculations. The method relies on extraction of these values from experiments and has been tested for absorption experiments to give excellent results.

  10. Photoabsorption cross section of OD at 115-180 nm

    NASA Technical Reports Server (NTRS)

    Nee, J. B.; Lee, L. C.

    1984-01-01

    The photoabsorption cross sections of OD in the 115-180 nm region were measured. The OD radicals were produced from a pulsed discharge in a mixture containing a trace of D2O in a few Torr of argon. Results are compared with the photoabsorption of OH previously measured.

  11. Total hadronic cross sections and π∓π+ scattering

    NASA Astrophysics Data System (ADS)

    Halzen, Francis; Igi, Keiji; Ishida, Muneyuki; Kim, C. S.

    2012-04-01

    Recent measurements of the inelastic and total proton-proton cross section at the LHC, and at cosmic ray energies by the Auger experiment, have quantitatively confirmed fits to lower energy data constrained by the assumption that the proton is asymptotically a black disk of gluons. We show that data on p¯(p)p, π∓p, and K∓p forward scattering support the related expectation that the asymptotic behavior of all cross sections is flavor independent. By using the most recent measurements from ATLAS, CMS, TOTEM, and Auger, we predict σtotpp(s=8TeV)=100.6±2.9mb and σtotpp(s=14TeV)=110.8±3.5mb, as well as refine the total cross section σtotpp(s=57TeV)=139.6±5.4mb. Our analysis also predicts the total π∓π+ cross sections as a function of s.

  12. Neutrino Cross-Section Measurements at the Spallation Neutron Source

    SciTech Connect

    Stancu, Ion

    2008-02-21

    In this paper we discuss the proposal to build a neutrino facility at the recently-completed Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory (ORNL). This facility can host an extensive, long-term program to study neutrino-nucleus cross-sections in the range of interest for nuclear astrophysics and nuclear theory.

  13. 10. Historic American Buildings Survey CROSS SECTION ST. PATRICK'S ...

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

    10. Historic American Buildings Survey CROSS SECTION - ST. PATRICK'S R. C. CHURCH c. 1839 - JAMES GALLIER, ARCHITECT, IN COLLECTION OF THE LOUISIANA STATE MUSEUM, JACKSON SQUARE, NEW ORLEANS, LA. - St. Patrick's Roman Catholic Church, 724 Camp Street, New Orleans, Orleans Parish, LA

  14. Absolute photoionization cross-section of the propargyl radical

    SciTech Connect

    Savee, John D.; Welz, Oliver; Taatjes, Craig A.; Osborn, David L.; Soorkia, Satchin; Selby, Talitha M.

    2012-04-07

    Using synchrotron-generated vacuum-ultraviolet radiation and multiplexed time-resolved photoionization mass spectrometry we have measured the absolute photoionization cross-section for the propargyl (C{sub 3}H{sub 3}) radical, {sigma}{sub propargyl}{sup ion}(E), relative to the known absolute cross-section of the methyl (CH{sub 3}) radical. We generated a stoichiometric 1:1 ratio of C{sub 3}H{sub 3} : CH{sub 3} from 193 nm photolysis of two different C{sub 4}H{sub 6} isomers (1-butyne and 1,3-butadiene). Photolysis of 1-butyne yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(26.1{+-}4.2) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(23.4{+-}3.2) Mb, whereas photolysis of 1,3-butadiene yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(23.6{+-}3.6) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(25.1{+-}3.5) Mb. These measurements place our relative photoionization cross-section spectrum for propargyl on an absolute scale between 8.6 and 10.5 eV. The cross-section derived from our results is approximately a factor of three larger than previous determinations.

  15. Neutron capture cross section of {sup 241}Am

    SciTech Connect

    Jandel, M.; Bredeweg, T. A.; Bond, E. M.; Chadwick, M. B.; Clement, R. R.; Couture, A.; O'Donnell, J. M.; Haight, R. C.; Kawano, T.; Reifarth, R.; Rundberg, R. S.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Agvaanluvsan, U.; Parker, W. E.; Wu, C. Y.; Becker, J. A.

    2008-09-15

    The neutron capture cross section of {sup 241}Am for incident neutrons from 0.02 eV to 320 keV has been measured with the detector for advanced neutron capture experiments (DANCE) at the Los Alamos Neutron Science Center. The thermal neutron capture cross section was determined to be 665{+-}33 b. Our result is in good agreement with other recent measurements. Resonance parameters for E{sub n}<12 eV were obtained using an R-matrix fit to the measured cross section. The results are compared with values from the ENDF/B-VII.0, Mughabghab, JENDL-3.3, and JEFF-3.1 evaluations. {gamma}{sub n} neutron widths for the first three resonances are systematically larger by 5-15% than the ENDF/B-VII.0 values. The resonance integral above 0.5 eV was determined to be 1553{+-}7 b. Cross sections in the resolved and unresolved energy regions above 12 eV were calculated using the Hauser-Feshbach theory incorporating the width-fluctuation correction of Moldauer. The calculated results agree well with the measured data, and the extracted averaged resonance parameters in the unresolved resonance region are consistent with those for the resolved resonances.

  16. Breakdown of conventional factorization for isolated photon cross sections

    SciTech Connect

    Berger, E.L.; Guo, Xiaofeng; Qiu, Jianwei

    1996-10-01

    Using {ital e{sup +}e{sup -} {r_arrow} {gamma} + X} as an example, we show that the conventional factorization theorem of perturbative QCD breaks down for isolated photon cross sections in a specific part of phase space. Implications are discussed.

  17. Elastic photonuclear cross sections for bremsstrahlung from relativistic ions

    NASA Astrophysics Data System (ADS)

    Mikkelsen, Rune E.; Sørensen, Allan H.; Uggerhøj, Ulrik I.

    2016-04-01

    In this paper, we provide a procedure to calculate the bremsstrahlung spectrum for virtually any relativistic bare ion with charge 6e or beyond, Z ⩾ 6 , in ultraperipheral collisions with target nuclei. We apply the Weizsäcker-Williams method of virtual quanta to model the effect of the distribution of nuclear constituents on the interaction of the ion with the radiation target. This leads to a bremsstrahlung spectrum peaking at 2 γ times the energy of the giant dipole resonance (γ is the projectile energy in units of its rest energy). A central ingredient in the calculation is the cross section for elastic scattering of photons on the ion. This is only available in the literature for a few selected nuclei and, usually, only in a rather restricted parameter range. Hence we develop a procedure applicable for all Z ⩾ 6 to estimate the elastic scattering. The elastic cross section is obtained at low to moderate photon energies, somewhat beyond the giant dipole resonance, by means of the optical theorem, a dispersion relation, and data on the total absorption cross section. The cross section is continued at higher energies by invoking depletion due to loss of coherence in the scattering. Our procedure is intended for any ion where absorption data is available and for moderate to high energies, γ ≳ 10 .

  18. Neutrino Cross-Section Measurements at the Spallation Neutron Source

    NASA Astrophysics Data System (ADS)

    Stancu, Ion

    2008-02-01

    In this paper we discuss the proposal to build a neutrino facility at the recently-completed Spallation Neutron Source (SNS) at the Oak Ridge National Laboratory (ORNL). This facility can host an extensive, long-term program to study neutrino-nucleus cross-sections in the range of interest for nuclear astrophysics and nuclear theory.

  19. Low-Energy Neutrino Cross-Section Measurements at SNS

    NASA Astrophysics Data System (ADS)

    Stancu, Ion

    2006-05-01

    We discuss the proposal to build a neutrino facility at the Spallation Neutron Source (SNS) presently under construction at the Oak Ridge National Laboratory (ORNL). This facility can host an extensive, long-term program to study neutrino-nucleus cross-sections in the range of interest for nuclear astrophysics and nuclear theory.

  20. Photoionization cross sections and oscillator strengths of neutral cesium

    NASA Astrophysics Data System (ADS)

    Haq, S. U.; Nadeem, Ali; Nawaz, M.

    2012-11-01

    The absolute photoionization cross sections from the 6p 2P1/2 excited state of cesium at threshold and above the threshold region have been measured using the saturation absorption technique. The photoionization cross section at the ionization threshold is determined as 22.6±3.6 Mb, whereas in the region above threshold its value ranges from 22 to 20 Mb for photoelectron energies up to 0.1 eV. A comparison of the photoionization cross sections with earlier reported theoretical and experimental data have been presented and are in good agreement within the uncertainty. In addition, the oscillator strengths of the 6p 2P1/2→n d 2D3/2 (21≤n≤60) Rydberg transitions of cesium have been calibrated using the threshold value of the photoionization cross section. A complete picture of the oscillator strengths from the present work and previously reported data from n=5-60 is presented.

  1. Stellar neutron capture cross sections of the tin isotopes

    SciTech Connect

    Wisshak, K.; Voss, F.; Theis, C.; Kaeppeler, F.; Guber, K.; Kazakov, L.; Kornilov, N.; Reffo, G.

    1996-09-01

    The neutron capture cross sections of {sup 114}Sn, {sup 115}Sn, {sup 116}Sn, {sup 117}Sn, {sup 118}Sn, and {sup 120}Sn were measured in the energy range from 3 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the {sup 7}Li({ital p},{ital n}){sup 7}Be reaction using a pulsed proton beam. Capture events were registered with the Karlsruhe 4{pi} barium fluoride detector. The experiment was complicated by the small ({ital n},{gamma}) cross sections of the proton magic tin isotopes and by the comparably low enrichment of the rare isotopes {sup 114}Sn and {sup 115}Sn. Despite significant corrections for capture of scattered neutrons and for isotopic impurities, the high efficiency and the spectroscopic quality of the BaF{sub 2} detector allowed the determination of the cross-section ratios with overall uncertainties of 1{endash}2{percent}, five times smaller compared to existing data. Based on these results, Maxwellian averaged ({ital n},{gamma}) cross sections were calculated for thermal energies between {ital kT}=10 and 100 keV. These data are used for a discussion of the solar tin abundance and for an improved determination of the isotopic {ital s}- and {ital r}-process components. {copyright} {ital 1996 The American Physical Society.}

  2. C+C Fusion Cross Sections Measurements for Nuclear Astrophysics

    NASA Astrophysics Data System (ADS)

    Almaraz-Calderon, S.; Carnelli, P. F. F.; Rehm, K. E.; Albers, M.; Alcorta, M.; Bertone, P. F.; Digiovine, B.; Esbensen, H.; Fernandez Niello, J. O.; Henderson, D.; Jiang, C. L.; Lai, J.; Marley, S. T.; Nusair, O.; Palchan-Hazan, T.; Pardo, R. C.; Paul, M.; Ugalde, C.

    2015-06-01

    Total fusion cross section of carbon isotopes were obtained using the newly developed MUSIC detector. MUSIC is a highly efficient, active target-detector system designed to measure fusion excitation functions with radioactive beams. The present measurements are relevant for understanding x-ray superbursts. The results of the first MUSIC campaign as well as the astrophysical implications are presented in this work.

  3. Reaction cross sections of carbon isotopes incident on a proton

    SciTech Connect

    Abu-Ibrahim, B.; Horiuchi, W.; Kohama, A.; Suzuki, Y.

    2008-03-15

    We systematically study total reaction cross sections of carbon isotopes with N=6-16 on a proton target for wide range of incident energies. An emphasis is put on the difference from the case of a carbon target. The calculations include the reaction cross sections of {sup 19,20,22}C at 40A MeV, the data of which have recently been measured at RIKEN. The Glauber theory is used to calculate the reaction cross sections. To describe the intrinsic structure of the carbon isotopes, we use a Slater determinant generated from a phenomenological mean-field potential, and construct the density distributions. To go beyond the simple mean-field model, we adopt two types of dynamical models: One is a core+n model for odd-neutron nuclei, and the other is a core+n+n model for {sup 16}C and {sup 22}C. We propose empirical formulas which are useful in predicting unknown cross sections.

  4. Thermal neutron capture cross sections of the potassium isotopes

    NASA Astrophysics Data System (ADS)

    Firestone, R. B.; Krtička, M.; Révay, Zs.; Szentmiklosi, L.; Belgya, T.

    2013-02-01

    Precise thermal neutron capture γ-ray cross sections σγ for 39,40,41K were measured on a natural potassium target with the guided neutron beam at the Budapest Reactor. The cross sections were internally standardized using a stoichiometric KCl target with well-known 35Cl(n,γ) γ-ray cross sections [Révay and Molnár, Radiochimica ActaRAACAP0033-823010.1524/ract.91.6.361.20027 91, 361 (2003); Molnár, Révay, and Belgya, Nucl. Instrum. Meth. Phys. Res. BNIMBEU0168-583X10.1016/S0168-583X(03)01529-5 213, 32 (2004)]. These data were combined with γ-ray intensities from von Egidy [von Egidy, Daniel, Hungerford, Schmidt, Lieb, Krusche, Kerr, Barreau, Borner, Brissot , J. Phys. G. Nucl. Phys.JPHGBM0305-461610.1088/0305-4616/10/2/013 10, 221 (1984)] and Krusche [Krusche, Lieb, Ziegler, Daniel, von Egidy, Rascher, Barreau, Borner, and Warner, Nucl. Phys. ANUPABL0375-947410.1016/0375-9474(84)90506-2 417, 231 (1984); Krusche, Winter, Lieb, Hungerford, Schmidt, von Egidy, Scheerer, Kerr, and Borner, Nucl. Phys. ANUPABL0375-947410.1016/0375-9474(85)90429-4 439, 219 (1985)] to generate nearly complete capture γ-ray level schemes. Total radiative neutron cross sections were deduced from the total γ-ray cross section feeding the ground state, σ0=Σσγ(GS) after correction for unobserved statistical γ-ray feeding from levels near the neutron capture energy. The corrections were performed with Monte Carlo simulations of the potassium thermal neutron capture decay schemes using the computer code dicebox where the simulated populations of low-lying levels are normalized to the measured cross section depopulating those levels. Comparisons of the simulated and experimental level feeding intensities have led to proposed new spins and parities for selected levels in the potassium isotopes where direct reactions are not a significant contribution. We determined the total radiative neutron cross sections σ0(39K)=2.28±0.04 b, σ0(40K)=90±7 b, and σ0(41K)=1.62±0.03 b from the

  5. Absolute photoionization cross-section of the methyl radical.

    SciTech Connect

    Taatjes, C. A.; Osborn, D. L.; Selby, T.; Meloni, G.; Fan, H.; Pratt, S. T.; Chemical Sciences and Engineering Division; SNL

    2008-01-01

    The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH{sub 3} photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; {sigma}{sub CH}(10.2 eV) = (5.7 {+-} 0.9) x 10{sup -18} cm{sup 2} and {sigma}{sub CH{sub 3}}(11.0 eV) = (6.0 {+-} 2.0) x 10{sup -18} cm{sup 2}. The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH{sub 3} and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.460 eV, (5.5 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.466 eV, and (4.9 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

  6. Section Preequating under the Equivalent Groups Design without IRT

    ERIC Educational Resources Information Center

    Guo, Hongwen; Puhan, Gautam

    2014-01-01

    In this article, we introduce a section preequating (SPE) method (linear and nonlinear) under the randomly equivalent groups design. In this equating design, sections of Test X (a future new form) and another existing Test Y (an old form already on scale) are administered. The sections of Test X are equated to Test Y, after adjusting for the…

  7. Prevalence of Myopia in France: A Cross-Sectional Analysis.

    PubMed

    Matamoros, Emilie; Ingrand, Pierre; Pelen, François; Bentaleb, Yacine; Weber, Michel; Korobelnik, Jean-François; Souied, Eric; Leveziel, Nicolas

    2015-11-01

    Refractive error (RE), particularly myopia, is the first cause of visual impairment throughout the world. This study aimed to depict the prevalence of myopia in a multicentric series of French individuals.This cross-sectional analysis was carried out between January 2012 and November 2013 in eye clinics dedicated to REs. Data collection included age, gender, best-corrected visual acuity, RE, and any relevant medical history involving laser refractive surgery and cataract surgery. Exclusion criteria consisted of monophthalm patients or those with incomplete demographic data.Prevalences in the overall population, by gender and by age groups were reported for mild myopia (-0.50 to -2.75 diopter [D]), moderate myopia (-3 to -5.75 D), high myopia (less than -6 D), and very high myopia (less than -10 D).The analysis included 100,429 individuals, mean age 38.5 years (± 16.9). Overall prevalence of myopia was 39.1% (95% CI 38.8-39.4). Prevalences of mild, moderate, high and very high myopia were respectively 25.1% (95% CI 25.4-24.9), 10.6% (95% CI 10.4-10.8), 3.4% (95% CI 3.3-3.5) and 0.5% (95% CI 0.48-0.57).Even if possible bias occurred in recruitment, our results are similar to RE data collected in nationally representative samples of Caucasians in other studies. This is to our knowledge, one of the largest European series of individuals dedicated to myopia prevalences in different age groups. These results confirm the importance of myopia as a major health issue in Western countries. PMID:26559276

  8. Stellar neutron capture cross sections of the Nd isotopes

    SciTech Connect

    Wisshak, K.; Voss, F.; Kaeppeler, F.; Kazakov, L.; Reffo, G.

    1998-01-01

    The neutron capture cross sections of {sup 142}Nd, {sup 143}Nd, {sup 144}Nd, {sup 145}Nd, {sup 146}Nd, and {sup 148}Nd have been measured in the energy range from 3 to 225 keV at the Karlsruhe 3.75 MV Van de Graaff accelerator. Neutrons were produced via the {sup 7}Li(p,n){sup 7}Be reaction by bombarding metallic Li targets with a pulsed proton beam. Capture events were registered with the Karlsruhe 4{pi} Barium Fluoride Detector. The cross sections were determined relative to the gold standard. The experiment was difficult due to the small cross sections of the even isotopes at or near the magic neutron number N=82, and also since the isotopic enrichment of some samples was comparably low. The necessary corrections for capture of scattered neutrons and for isotopic impurities could be determined reliably thanks to the high efficiency and the spectroscopic quality of the BaF{sub 2} detector, resulting in a consistent set of (n,{gamma}) cross sections for the six stable neodymium isotopes involved in the s process with typical uncertainties of 1.5{endash}2{percent}. From these data, Maxwellian averaged cross sections were calculated between kT=10 and 100 keV. The astrophysical implications of these results were investigated in an s-process analysis, which deals with the role of the s-only isotope {sup 142}Nd for the N{sub s}{l_angle}{sigma}{r_angle} systematics near the magic neutron number N=82, the decomposition of the Nd abundances into the respective r-, s-, and p-process components, and the interpretation of isotopic anomalies in meteoritic material. {copyright} {ital 1998} {ital The American Physical Society}

  9. Equity in the delivery of community healthcare to older people: findings from 10/66 Dementia Research Group cross-sectional surveys in Latin America, China, India and Nigeria

    PubMed Central

    2011-01-01

    Background To describe patterns of recent health service utilisation, and consequent out-of-pocket expenses among older people in countries with low and middle incomes, and to assess the equity with which services are accessed and delivered. Methods 17,944 people aged 65 years and over were assessed in one-phase population-based cross-sectional surveys in geographically-defined catchment areas in nine countries - urban and rural sites in China, India, Mexico and Peru, urban sites in Cuba, Dominican Republic, Puerto Rico and Venezuela, and a rural site in Nigeria. The main outcome was use of community health care services in the past 3 months. Independent associations were estimated with indicators of need (dementia, depression, physical impairments), predisposing factors (age, sex, and education), and enabling factors (household assets, pension receipt and health insurance) using Poisson regression to generate prevalence ratios and fixed effects meta-analysis to combine them. Results The proportion using healthcare services varied from 6% to 82% among sites. Number of physical impairments (pooled prevalence ratio 1.37, 95% CI 1.26-1.49) and ICD-10 depressive episode (pooled PR 1.21, 95% CI 1.07-1.38) were associated with service use, but dementia was inversely associated (pooled PR 0.93, 95% CI 0.90-0.97). Other correlates were female sex, higher education, more household assets, receiving a pension, and health insurance. Standardisation for age, sex, physical impairments, depression and dementia did not explain variation in service use. There was a strong borderline significant ecological correlation between the proportion of consultations requiring out-of-pocket costs and the prevalence of health service use (r = -0.50, p = 0.09). Conclusions While there was little evidence of ageism, inequity was apparent in the independent enabling effects of education and health insurance cover, the latter particularly in sites where out-of-pocket expenses were common, and

  10. Calculation of photoionization cross section near auto-ionizing lines and magnesium photoionization cross section near threshold

    NASA Technical Reports Server (NTRS)

    Moore, E. N.; Altick, P. L.

    1972-01-01

    The research performed is briefly reviewed. A simple method was developed for the calculation of continuum states of atoms when autoionization is present. The method was employed to give the first theoretical cross section for beryllium and magnesium; the results indicate that the values used previously at threshold were sometimes seriously in error. These threshold values have potential applications in astrophysical abundance estimates.

  11. Ion dipole capture cross sections at low ion and rotational energies - Comparison of integrated capture cross sections with reaction cross sections for NH3 and H2O parent-ion collisions.

    NASA Technical Reports Server (NTRS)

    Dugan, J. V., Jr.; Canright, R. B., Jr.

    1972-01-01

    The numerical capture cross section is calculated from the capture ratio, defined as the fraction of trajectories reaching a prescribed minimum separation of 3 A. The calculated capture cross sections for a rotational temperature of 77 K suggest large reaction cross sections in 80 K experiments for the large dipole-moment target, methyl cyanide.

  12. Developing Scientific Reasoning Through Drawing Cross-Sections

    NASA Astrophysics Data System (ADS)

    Hannula, K. A.

    2012-12-01

    Cross-sections and 3D models of subsurface geology are typically based on incomplete information (whether surface geologic mapping, well logs, or geophysical data). Creating and evaluating those models requires spatial and quantitative thinking skills (including penetrative thinking, understanding of horizontality, mental rotation and animation, and scaling). However, evaluating the reasonableness of a cross-section or 3D structural model also requires consideration of multiple possible geometries and geologic histories. Teaching students to create good models requires application of the scientific methods of the geosciences (such as evaluation of multiple hypotheses and combining evidence from multiple techniques). Teaching these critical thinking skills, especially combined with teaching spatial thinking skills, is challenging. My Structural Geology and Advanced Structural Geology courses have taken two different approaches to developing both the abilities to visualize and to test multiple models. In the final project in Structural Geology (a 3rd year course with a pre-requisite sophomore mapping course), students create a viable cross-section across part of the Wyoming thrust belt by hand, based on a published 1:62,500 geologic map. The cross-section must meet a number of geometric criteria (such as the template constraint), but is not required to balance. Each student tries many potential geometries while trying to find a viable solution. In most cases, the students don't visualize the implications of the geometries that they try, but have to draw them and then erase their work if it does not meet the criteria for validity. The Advanced Structural Geology course used Midland Valley's Move suite to test the cross-sections that they made in Structural Geology, mostly using the flexural slip unfolding algorithm and testing whether the resulting line lengths balanced. In both exercises, students seemed more confident in the quality of their cross-sections when the

  13. Validity of Hansen-Roach cross sections in low-enriched uranium systems

    SciTech Connect

    Busch, R.D. ); O'Dell, R.D. )

    1991-01-01

    Within the nuclear criticality safety community, the Hansen-Roach 16 group cross section set has been the standard'' for use in k{sub eff} calculations over the past 30 years. Yet even with its widespread acceptance, there are still questions about its validity and adequacy, about the proper procedure for calculating the potential scattering cross section, {sigma}{sub p}, for uranium and plutonium, and about the concept of resonance self shielding and its impact on cross sections. This paper attempts to address these questions. It provides a brief background on the Hansen-Roach cross sections. Next is presented a review of resonances in cross sections, self shielding of these resonances, and the use of {sigma}{sub p} to characterize resonance self shielding. Three prescriptions for calculating {sigma}{sub p} are given. Finally, results of several calculations of k{sub eff} on low-enriched uranium systems are provided to confirm the validity of the Hansen-Roach cross sections when applied to such systems.

  14. Hypovitaminosis D in Delirium: a Retrospective Cross-sectional Study

    PubMed Central

    Ford, Jennifer; Hategan, Ana; Bourgeois, James A.; Tisi, Daniel K.; Xiong, Glen L.

    2013-01-01

    Background As vitamin D may have a neuroprotective effect, the authors studied the association of biomarkers of vitamin D status and delirium to see if low vitamin D status was common in delirium cases. Methods Biochemical measures of vitamin D (25-hydroxyvitamin D [25-OHD]) and calcium metabolism were used in this retrospective cross-sectional analysis of adult in-patients with delirium, admitted at three Canadian academic hospitals from January 2011 to July 2012. Primary outcome was to determine estimates of the prevalence of hypovitaminosis D in this group in whom vitamin D was checked. Results Seventy-one (5.8%) out of 1,232 delirium inpatients had their vitamin D measured. Thirty-nine (55%) showed vitamin D insufficiency (25-OHD of 25-75 nmol/L) and 8 (11%) showed vitamin D deficiency (25-OHD < 25 nmol/L). Mean serum 25-OHD levels were lower in males (57.1±7.7 nmol/L) than in females (78.2±6.1 nmol/L), p = .01, even when controlled for age and season. Men were younger than the women (74.4±2.3 vs. 82.4±1.7, p = .005). Mean age was 78.7±1.5 years, and 33 (47%) were male. Conclusions Although vitamin D is rarely checked during delirium workup and/or management, high rates of hypovitaminosis D were found to be common in the delirium in-patients in whom it was checked. Larger studies would be needed to estimate the prevalence of hypovitaminosis D in delirium and whether hypovitaminosis D plays a role in the pathogenesis of delirium. PMID:24278095

  15. Choroidal thickness in pregnant women: a cross-sectional study

    PubMed Central

    Liu, Ru; Kuang, Guo-Ping; Luo, Di-Xian; Lu, Xiao-He

    2016-01-01

    AIM To investigate choroidal thickness in pregnant women and compare the measurements with those of normal nonpregnant women. METHODS Using enhanced depth imaging optical coherence tomography (EDI-OCT), choroidal thickness was measured at the fovea and at 1 mm and 3 mm superior, inferior, temporal, and nasal to the fovea in both healthy pregnant women and nonpregnant women. Pearson correlation analysis was performed to evaluate the relationships between subfoveal choroidal thickness (SFCT) and the demographic and ocular parameters. Pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects model when Meta-analyses were conducted. RESULTS Comparison of choroidal thickness between the groups showed that it was significantly greater in healthy pregnant women's eyes than in normal nonpregnant women's eyes at all locations except at 3 mm superior and 3 mm temporal from the fovea (P<0.05). The mean SFCT was 344.13±50.94 µm in healthy pregnant women's eyes and 315.03±60.57 µm in normal nonpregnant women's eyes, with a statistically significant difference (P=0.008). Pearson correlation analysis showed that age and axial length were significantly related to SFCT in healthy pregnant women, normal nonpregnant women, and all subjects. The results of our cross-sectional study were consistent with the results of the further Meta-analysis, with a pooled weighted mean difference (WMD) of 33.66 µm (95% CI: 26.16 to 41.15) for SFCT. CONCLUSION Our results, along with the comprehensive Meta-analysis, suggest that choroidal thickness in healthy pregnant women is greater than that in normal nonpregnant women. PMID:27588276

  16. Improved multimodal admittance method in varying cross section waveguides.

    PubMed

    Maurel, Agnès; Mercier, Jean-François; Pagneux, Vincent

    2014-04-01

    An improved version of the multimodal admittance method in acoustic waveguides with varying cross sections is presented. This method aims at a better convergence with respect to the number of transverse modes that are taken into account. It is based on an enriched modal expansion of the pressure: the N first modes are the local transverse modes and a supplementary (N+1)th mode, called boundary mode, is a well-chosen transverse function orthogonal to the N first modes. This expansion leads to the classical form of the coupled mode equations where the component of the boundary mode is of evanescent character. Under this form, the multimodal admittance method based on the Riccati equation on the admittance matrix (the Dirichlet-to-Neumann operator) is straightforwardly implemented. With this supplementary mode, in addition to the improvement of the convergence of the pressure field, results show a superconvergence of the scattered field outside of the varying cross sections region. PMID:24711716

  17. Elastic breakup cross sections of well-bound nucleons

    NASA Astrophysics Data System (ADS)

    Wimmer, K.; Bazin, D.; Gade, A.; Tostevin, J. A.; Baugher, T.; Chajecki, Z.; Coupland, D.; Famiano, M. A.; Ghosh, T. K.; Grinyer, G. F.; Howard, M. E.; Kilburn, M.; Lynch, W. G.; Manning, B.; Meierbachtol, K.; Quarterman, P.; Ratkiewicz, A.; Sanetullaev, A.; Showalter, R. H.; Stroberg, S. R.; Tsang, M. B.; Weisshaar, D.; Winkelbauer, J.; Winkler, R.; Youngs, M.

    2014-12-01

    The 9Be(28Mg,27Na ) one-proton removal reaction with a large proton separation energy of Sp(28Mg ) =16.79 MeV is studied at intermediate beam energy. Coincidences of the bound 27Na residues with protons and other light charged particles are measured. These data are analyzed to determine the percentage contributions to the proton removal cross section from the elastic and inelastic nucleon removal mechanisms. These deduced contributions are compared with the eikonal reaction model predictions and with the previously measured data for reactions involving the removal of more weakly bound protons from lighter nuclei. The role of transitions of the proton between different bound single-particle configurations upon the elastic breakup cross section is also quantified in this well-bound case. The measured and calculated elastic breakup fractions are found to be in good agreement.

  18. Experimental validation of lead cross sections for scale and MCNP

    SciTech Connect

    Henrikson, D.J.

    1995-12-01

    Moving spent nuclear fuel between facilities often requires the use of lead-shielded casks. Criticality safety that is based upon calculations requires experimental validation of the fuel matrix and lead cross section libraries. A series of critical experiments using a high-enriched uranium-aluminum fuel element with a variety of reflectors, including lead, has been identified. Twenty-one configurations were evaluated in this study. The fuel element was modelled for KENO V.a and MCNP 4a using various cross section sets. The experiments addressed in this report can be used to validate lead-reflected calculations. Factors influencing calculated k{sub eff} which require further study include diameters of styrofoam inserts and homogenization.

  19. Accurate Development of Thermal Neutron Scattering Cross Section Libraries

    SciTech Connect

    Hawari, Ayman; Dunn, Michael

    2014-06-10

    The objective of this project is to develop a holistic (fundamental and accurate) approach for generating thermal neutron scattering cross section libraries for a collection of important enutron moderators and reflectors. The primary components of this approach are the physcial accuracy and completeness of the generated data libraries. Consequently, for the first time, thermal neutron scattering cross section data libraries will be generated that are based on accurate theoretical models, that are carefully benchmarked against experimental and computational data, and that contain complete covariance information that can be used in propagating the data uncertainties through the various components of the nuclear design and execution process. To achieve this objective, computational and experimental investigations will be performed on a carefully selected subset of materials that play a key role in all stages of the nuclear fuel cycle.

  20. Evolving roles of cross-sectional imaging in Crohn's disease.

    PubMed

    Magarotto, Andrea; Orlando, Stefania; Coletta, Marina; Conte, Dario; Fraquelli, Mirella; Caprioli, Flavio

    2016-09-01

    The implementation of cross-sectional imaging techniques for the clinical management of Crohn's disease patients has steadily grown over the recent years, thanks to a series of technological advances, including the evolution of contrast media for magnetic resonance, computed tomography and bowel ultrasound. This has resulted in a continuous improvement of diagnostic accuracy and capability to detect Crohn's disease-related complications. Additionally, a progressive widening of indications for cross-sectional imaging in Crohn's disease has been put forward, thus leading to hypothesize that in the near future imaging techniques can increasingly complement endoscopy in most clinical settings, including the grading of disease activity and the assessment of mucosal healing or Crohn's disease post-surgical recurrence. PMID:27338853

  1. Torsion of Flanged Members with Cross Sections Restrained Against Warping

    NASA Technical Reports Server (NTRS)

    Hill, H N

    1943-01-01

    The longitudinal stresses and the stiffness of flange members - I-beams, channels, and Z-bars - were investigated when these members were subjected to torque with constraint against cross-sectional warping. Measured angles of rotation agreed with corresponding calculated values in which the torsion bending factor of the cross section was involved; the agreement was better for the I-beam and the Z-bar than for the channel. Longitudinal stresses measured at the mid-span were found to agree with the calculated values that involved unit warping as well as the torsion-bending factors: the channel showed the greatest discrepancy between measured and calculated values. When commonly given expressions for rotations and maximum longitudinal stresses in a twisted I-beam were applied to the channel and to the Z-bar, values were obtained that were in reasonably good agreement with values obtained by the method of torsion-bending constant and unit warping.

  2. Vortex breakdown in closed containers with polygonal cross sections

    SciTech Connect

    Naumov, I. V. Dvoynishnikov, S. V.; Kabardin, I. K.; Tsoy, M. A.

    2015-12-15

    The vortex breakdown bubble in the confined flow generated by a rotating lid in closed containers with polygonal cross sections was analysed both experimentally and numerically for the height/radius aspect ratio equal to 2. The stagnation point locations of the breakdown bubble emergence and the corresponding Reynolds number were determined experimentally and in addition computed numerically by STAR-CCM+ CFD software for square, pentagonal, hexagonal, and octagonal cross section configurations. The flow pattern and the velocity were observed and measured by combining the seeding particle visualization and the temporal accuracy of laser Doppler anemometry. The vortex breakdown size and position on the container axis were determined for Reynolds numbers, ranging from 1450 to 2400. The obtained results were compared with the flow structure in the closed container of cubical and cylindrical configurations. It is shown that the measured evolution of steady vortex breakdown is in close agreement with the numerical results.

  3. Radar cross section of a planar fractal tree

    NASA Astrophysics Data System (ADS)

    Demiris, John

    1989-03-01

    Electromagnetic scattering from trees and vegetation is of prime importance in radar and remote sensing. The actual problem of scattering from trees is rather complicated and involves three dimensional scattering from lossy, electrically large, and randomly oriented objects. In this thesis, the radar cross section of a planar fractal tree is considered. Although a planar tree is far from being real, scattering from it shed light on the scattering phenomenon from an actual tree. The planar tree is generated using fractal geometry and its branches are considered perfectly conducting. The tree is illuminated by a plane wave and the problem is solved using the moment method. Data is presented for the radar cross section for different branching angles of the tree and at different frequencies.

  4. Cross-Section Measurements with the Radioactive Isotope Accelerator (RIA)

    SciTech Connect

    Stoyer, M A; Moody, K J; Wild, J F; Patin, J B; Shaughnessy, D A; Stoyer, N J; Harris, L J

    2002-11-19

    RIA will produce beams of exotic nuclei of unprecedented luminosity. Preliminary studies of the feasibility of measuring cross-sections of interest to the science based stockpile stewardship (SBSS) program will be presented, and several experimental techniques will be discussed. Cross-section modeling attempts for the A = 95 mass region will be shown. In addition, several radioactive isotopes could be collected for target production or medical isotope purposes while the main in-beam experiments are running. The inclusion of a broad range mass analyzer (BRAMA) capability at RIA will enable more effective utilization of the facility, enabling the performance of multiple experiments at the same time. This option will be briefly discussed.

  5. Evaluation of Neutron Resonance Cross Section Data at GELINA

    NASA Astrophysics Data System (ADS)

    Schillebeeckx, P.; Becker, B.; Capote, R.; Emiliani, F.; Guber, K.; Heyse, J.; Kauwenberghs, K.; Kopecky, S.; Lampoudis, C.; Massimi, C.; Mondelaers, W.; Moxon, M.; Noguere, G.; Plompen, A. J. M.; Pronyaev, V.; Siegler, P.; Sirakov, I.; Trkov, A.; Volev, K.; Zerovnik, G.

    2014-05-01

    Over the last decade, the EC-JRC-IRMM, in collaboration with other institutes such as INRNE Sofia (BG), INFN Bologna (IT), ORNL (USA), CEA Cadarache (FR) and CEA Saclay (FR), has made an intense effort to improve the quality of neutron-induced cross section data in the resonance region. These improvements relate to both the infrastructure of the facility and the measurement setup, and the data reduction and analysis procedures. As a result total and reaction cross section data in the resonance region with uncertainties better than 0.5 % and 2 %, respectively, can be produced together with evaluated data files for both the resolved and unresolved resonance region. The methodology to produce full ENDF compatible files, including covariances, is illustrated by the production of resolved resonance parameter files for 241Am, Cd and W and an evaluation for 197Au in the unresolved resonance region.

  6. Simultaneously Produced Upsilon and Jpsi Production Cross Section

    NASA Astrophysics Data System (ADS)

    Dilsiz, Kamuran; CMS Collaboration

    2016-03-01

    The observation and cross section of simultaneously produced Γ and J / Ψ mesons are performed using 20 fb-1 integrated luminosity in proton-proton collisions at 8 TeV energy recorded with the CMS detector. Both mesons are fully reconstructed from their final states. To extract the signal yield, an extended maximum likelihood fit is used on two (invariant mass of Γ and J / Ψ) and three (invariant mass of Γ and J / Ψ , and c τ) event variables. A data-based method is used to study muon reconstruction, trigger and offline selection efficiencies. The cross section in the fiducial region, defined as pTμ > 3 . 5 GeV/c and | ημ | < 2 . 4 for Γ meson and as pTμ > 2 GeV/c and | ημ | < 2 . 4 for J / Ψ meson, will be reported.

  7. Vortex breakdown in closed containers with polygonal cross sections

    NASA Astrophysics Data System (ADS)

    Naumov, I. V.; Dvoynishnikov, S. V.; Kabardin, I. K.; Tsoy, M. A.

    2015-12-01

    The vortex breakdown bubble in the confined flow generated by a rotating lid in closed containers with polygonal cross sections was analysed both experimentally and numerically for the height/radius aspect ratio equal to 2. The stagnation point locations of the breakdown bubble emergence and the corresponding Reynolds number were determined experimentally and in addition computed numerically by STAR-CCM+ CFD software for square, pentagonal, hexagonal, and octagonal cross section configurations. The flow pattern and the velocity were observed and measured by combining the seeding particle visualization and the temporal accuracy of laser Doppler anemometry. The vortex breakdown size and position on the container axis were determined for Reynolds numbers, ranging from 1450 to 2400. The obtained results were compared with the flow structure in the closed container of cubical and cylindrical configurations. It is shown that the measured evolution of steady vortex breakdown is in close agreement with the numerical results.

  8. Improved activation cross sections for vanadium and titanium

    SciTech Connect

    Muir, D.W.; Arthur, E.D.

    1983-01-01

    Vanadium alloys such as V-20Ti and V-Cr-Ti are attractive candidates for use as structural materials in fusion-reactor blankets. The virtual absence of long-lived activation products in these alloys suggest the possibility of reprocessing on an intermediate time scale. We have employed the modern Hauser-Feshbach nuclear-model code GNASH to calculate cross sections for neutron-activation reactions in /sup 50/V and /sup 51/V, to allow a more accurate assessment of induced radioactivity in vanadium alloys. In addition, cross sections are calculated for the reactions /sup 46/Ti(n,2n) and /sup 45/Ti(n,2n) in order to estimate the production of /sup 44/Ti, a 1.2-MeV gamma-ray source with a half-life of 47 years.

  9. Impact dynamics of granular jets with noncircular cross sections.

    PubMed

    Cheng, Xiang; Gordillo, Leonardo; Zhang, Wendy W; Jaeger, Heinrich M; Nagel, Sidney R

    2014-04-01

    Using high-speed photography, we investigate two distinct regimes of the impact dynamics of granular jets with noncircular cross sections. In the steady-state regime, we observe the formation of thin granular sheets with anisotropic shapes and show that the degree of anisotropy increases with the aspect ratio of the jet's cross section. Our results illustrate the liquidlike behavior of granular materials during impact and demonstrate that a collective hydrodynamic flow emerges from strongly interacting discrete particles. We discuss the analogy between our experiments and those from the Relativistic Heavy Ion Collider, where similar anisotropic ejecta from a quark-gluon plasma have been observed in heavy-ion impact. PMID:24827235

  10. Cross-Section Measurements with the Radioactive Isotope Accelerator (ria)

    NASA Astrophysics Data System (ADS)

    Stoyer, M. A.; Moody, K. J.; Wild, J. F.; Patin, J. B.; Shaughnessy, D. A.; Stoyer, N. J.; Harris, L. J.

    2003-10-01

    RIA will produce beams of exotic nuclei of unprecedented luminosity. Preliminary studies of the feasibility of measuring cross-sections of interest to the science based stockpile stewardship (SBSS) program will be presented, and several experimental techniques will be discussed. Cross-section modeling attempts for the A = 95 mass region will be shown. In addition, several radioactive isotopes could be collected for target production or medical isotope purposes while the main in-beam experiments are running. The inclusion of a broad range mass analyzer (BRAMA) capability at RIA will enable more effective utilization of the facility, enabling the performance of multiple experiments at the same time. This option will be briefly discussed.

  11. Neutron Capture Cross Sections of 236U and 234U

    NASA Astrophysics Data System (ADS)

    Rundberg, R. S.; Bredeweg, T. A.; Bond, E. M.; Haight, R. C.; Hunt, L. F.; Kronenberg, A.; O'Donnell, J. M.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.

    2006-03-01

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-π solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations.

  12. Neutron Capture Cross Sections of 236U and 234U

    SciTech Connect

    Rundberg, R. S.; Bredeweg, T. A.; Bond, E. M.; Haight, R. C.; Hunt, L. F.; O'Donnell, J. M.; Schwantes, J. M.; Ullmann, J. L.; Vieira, D. J.; Wilhelmy, J. B.; Wouters, J. M.; Kronenberg, A.

    2006-03-13

    Accurate neutron capture cross sections of the actinide elements at neutron energies up to 1 MeV are needed to better interpret archived nuclear test data, for post-detonation nuclear attribution, and the Advanced Fuel Cycle Initiative. The Detector for Advance Neutron Capture Experiments, DANCE, has unique capabilities that allow the differentiation of capture gamma rays from fission gamma rays and background gamma rays from scattered neutrons captured by barium isotopes in the barium fluoride scintillators. The DANCE array has a high granularity, 160 scintillators, high efficiency, and nearly 4-{pi} solid angle. Through the use of cuts in cluster multiplicity and calorimetric energy the capture gamma-rays are differentiated from other sources of gamma rays. The preliminary results for the capture cross sections of 236U are in agreement with the ENDF/B-VI evaluation. The preliminary results for 234U lower are than ENDF/B-VI evaluation and are closer to older evaluations.

  13. Optimization of negative central shear discharges in shaped cross sections

    SciTech Connect

    Turnbull, A.D., Chu, M.S., Taylor, T.S., Casper, T.A., Rice, B.W.; Greene, J.M., Greenfield, C.M., La Haye, R.J., Lao, L.L., Lee, B.J.; Miller, R.L., Ren, C., Strait, E.J., Tritz, K.; Rettig, C.L., Rhodes, T.L.; Sauter, O.

    1996-10-01

    Magnetohydrodynamic (MHD) stability analyses of Negative Central Shear (NCS) equilibria have revealed a new understanding of the limiting MHD instabilities in NCS experiments. Ideal stability calculations show a synergistic effect between cross section shape and pressure profile optimization; strong shaping and broader pressure independently lead to moderately higher {Beta} limits, but broadening of the pressure profile in a strongly dee-shaped cross- section leads to a dramatic increase in the ideal {Beta} limit. Localized resistive interchange (RI) modes can be unstable in the negative shear region and are most restrictive for peaked pressure profiles. Resistive global modes can also be destabilized significantly below the ideal P limit. Experiments largely confirm the general trends, and diagnostic measurements and numerical stability calculations are found to be in good qualitative agreement. Observed disruptions in NCS discharges with L-mode edge and strongly peaked pressure, appear to be initiated by interactions between the RI, and the global ideal and resistive modes.

  14. Uncertainties in Measurements and Calculations of Nonelastic Cross Sections

    SciTech Connect

    Dietrich, F S

    2008-08-05

    Scatter in presently available measurements of the nonelastic cross section indicates that this quantity is rather poorly known (approximately 5-10%). We will show examples of this, together with results from a new technique that shows promise of reducing these uncertainties to {approx}2-3% in the range of a few MeV to a few tens of MeV. Comparison of results obtained using this new technique with optical model calculations suggests that global optical potentials are not reliable for predicting nonelastic cross sections to better than roughly 5%. In view of these results, we suggest that a limited set of high-precision measurements should be made to clarify the experimental picture and guide the further development of optical models.

  15. Intermanifold similarities in partial photoionization cross sections of helium

    NASA Astrophysics Data System (ADS)

    Schneider, Tobias; Liu, Chien-Nan; Rost, Jan-Michael

    2002-04-01

    Using the eigenchannel R-matrix method we calculate partial photoionization cross sections from the ground state of the helium atom for incident photon energies up to the N=9 manifold. The wide energy range covered by our calculations permits a thorough investigation of general patterns in the cross sections which were first discussed by Menzel and coworkers [Phys. Rev. A 54, 2080 (1996)]. The existence of these patterns can easily be understood in terms of propensity rules for autoionization. As the photon energy is increased the regular patterns are locally interrupted by perturber states until they fade out indicating the progressive breakdown of the propensity rules and the underlying approximate quantum numbers. We demonstrate that the destructive influence of isolated perturbers can be compensated with an energy-dependent quantum defect.

  16. SECTION D, WITH FLAT GROUP BURIAL MARKER AT RIGHT FOREGROUND. ...

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

    SECTION D, WITH FLAT GROUP BURIAL MARKER AT RIGHT FOREGROUND. VIEW TO NORTHWEST. - Rock Island National Cemetery, Rock Island Arsenal, 0.25 mile north of southern tip of Rock Island, Rock Island, Rock Island County, IL

  17. Inclusive jet cross-section measurement at CDF

    SciTech Connect

    Norniella, Olga; /Barcelona, IFAE

    2007-05-01

    The CDF Collaboration has measured the inclusive jet cross section using 1992-93 collider data at 1.8 TeV. The CDF measurement is in very good agreement with NLO QCD predictions for transverse energies (E{sub T}) below 200 GeV. However, it is systematically higher than NLO QCD predictions for E{sub T} above 200 GeV.

  18. Top Quark Production Cross Section at the Tevatron

    SciTech Connect

    Shabalina, E.; /Chicago U.

    2006-05-01

    An overview of the preliminary results of the top quark pair production cross section measurements at a center-of-mass energy of 1.96 TeV carried out by the CDF and D0 collaborations is presented. The data samples used for the analyses are collected in the current Tevatron run and correspond to an integrated luminosity from 360 pb{sup -1} up to 760 pb{sup -1}.

  19. 13. Photocopy of drawing dated January 20, 1958, CROSS SECTION, ...

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

    13. Photocopy of drawing dated January 20, 1958, CROSS SECTION, REHABILITATION OF PIERSHED AT FOOT OF 29TH ST. city of New York Department of Marine and Aviation, Contract 3049, Drawing 3. (On file, City of New York Department of Ports and Trade). - South Brooklyn Freight Terminal, 29th Street Pier, Opposite end of Twenty-ninth Street on upper New York Bay, Brooklyn, Kings County, NY

  20. Radar cross-sectional study using noise radar

    NASA Astrophysics Data System (ADS)

    Freundorfer, A. P.; Siddiqui, J. Y.; Antar, Y. M. M.

    2015-05-01

    A noise radar system is proposed with capabilities to measure and acquire the radar cross-section (RCS) of targets. The proposed system can cover a noise bandwidth of near DC to 50 GHz. The noise radar RCS measurements were conducted for selective targets like spheres and carpenter squares with and without dielectric bodies for a noise band of 400MHz-5000MHz. The bandwidth of operation was limited by the multiplier and the antennae used.

  1. Cross-section data for selected Puerto Rico streams

    USGS Publications Warehouse

    Colon-Dieppa, Eloy; Gonzalez, Ralph

    1978-01-01

    The data presented are for delineating the inundation which could be expected by floods of selected magnitudes in Puerto Rico. These cross section data can be used in Flood Insurance Administration studies and in other studies related to the planning, development, and management of flood plains. The data were collected by the Caribbean District of the Water Resources Division of the U.S. Geological Survey in cooperation with the Puerto Rico Department of Natural Resources. (Woodard-USGS)

  2. Differential collision cross-sections for atomic oxygen

    NASA Technical Reports Server (NTRS)

    Torr, Douglas G.

    1991-01-01

    Differential collision cross-sections of O on N2 and other gases were measured to understand vehicle-environmental contamination effects in orbit. The following subject areas are also covered: groundbased scientific observations of rocket releases during NICARE-1; data compression study for the UVI; science priorities for UV imaging in the mid-1990's; and assessment of optimizations possible in UV imaging systems.

  3. W and Z cross sections at the Tevatron

    SciTech Connect

    T. Dorigo

    2003-07-01

    The CDF and D0 experiments at the Tevatron have used p{bar p} collisions at {radical}s = 1.96 TeV to measure the cross section of W and Z boson production using several leptonic final states. An indirect measurement of the total W width has been extracted, and the lepton charge asymmetry in Drell-Yan production has been studied up to invariant masses of 600 GeV/c{sup 2}.

  4. Overview of recent U235 neutron cross section evaluation work

    SciTech Connect

    Lubitz, C.

    1998-10-01

    This report is an overview (through 1997) of the U235 neutron cross section evaluation work at Oak Ridge National Laboratory (ORNL), AEA Technology (Harwell) and Lockheed Martin Corp.-Schenectady (LMS), which has influenced, or appeared in, ENDF/B-VI through Release 5. The discussion is restricted to the thermal and resolved resonance regions, apart from some questions about the unresolved region which still need investigation. The important role which benchmark testing has played will be touched on.

  5. Top-Quark Cross Section and Properties at the Tevatron

    SciTech Connect

    Wagner, Wolfgang; /Wuppertal U.

    2009-09-01

    At the Tevatron, the collider experiments CDF and D0 have data sets at their disposal that compromise several hundreds of reconstructed top-antitop-quark pairs and allow for precision measurements of the cross section and production and decay properties. Besides comparing the measurements to standard model predictions, these data sets open a window to physics beyond the standard model. Dedicated analyses look for new heavy gauge bosons, fourth generation quarks, and flavor-changing neutral currents.

  6. Neutrino and Antineutrino Cross sections at MiniBooNE

    SciTech Connect

    Dharmapalan, Ranjan; /Alabama U.

    2011-10-01

    The MiniBooNE experiment has reported a number of high statistics neutrino and anti-neutrino cross sections -among which are the charged current quasi-elastic (CCQE) and neutral current elastic (NCE) neutrino scattering on mineral oil (CH2). Recently a study of the neutrino contamination of the anti-neutrino beam has concluded and the analysis of the anti-neutrino CCQE and NCE scattering is ongoing.

  7. Top quark pair production cross section at the Tevatron

    SciTech Connect

    Cortiana, Giorgio; /INFN, Padua /Padua U.

    2008-04-01

    Top quark pair production cross section has been measured at the Tevatron by CDF and D0 collaborations using different channels and methods, in order to test standard model predictions, and to search for new physics hints affecting the t{bar t} production mechanism or decay. Measurements are carried out with an integrated luminosity of 1.0 to 2.0 fb{sup -1}, and are found to be consistent with standard model expectations.

  8. Cross-sectional echocardiographic diagnosis of systemic venous return.

    PubMed Central

    Huhta, J C; Smallhorn, J F; Macartney, F J; Anderson, R H; de Leval, M

    1982-01-01

    To determine the sensitivity and specificity of cross-sectional echocardiography in diagnosing anomalous systemic venous return we used the technique in 800 consecutive children with congenital heart disease and whom the diagnosis was ultimately confirmed by angiography. Cross-sectional echocardiography was performed without prior knowledge of the diagnosis in all but 11 patients, who were recalled because of a known abnormality of atrial situs. The sensitivity of cross-sectional echocardiographic detection of various structures was as follows: right superior vena cava 792/792 (100%); left superior vena cava 46/48 (96%); bilateral superior vena cava 38/40 (95%); bridging innominate vein with bilateral superior vena cava 13/18 (72%); connection of superior caval segment to heart (coronary sinus or either atrium) (100%); absence of suprarenal inferior vena cava 23/23 (100%); azygos continuation of the inferior vena cava 31/33 (91%); downstream connection of azygos continuation, once seen, 21/21 (100%); partial anomalous hepatic venous connection (one hepatic vein not connected to the inferior vena cava) 1/1 (100%); total anomalous hepatic venous connection (invariably associated with left isomerism) 23/23 (100%). The specificity of each above diagnoses was 100% except in one infant with exomphalos in whom absence of the suprarenal inferior vena cava was incorrectly diagnosed. Thus cross-sectional echocardiography is an extremely specific and highly sensitive method of recognizing anomalous systemic venous return. It is therefore of great value of planning both cardiac catheterisation and cannulation for open heart surgery. Images PMID:6751361

  9. Vibrational cross sections for positron scattering by nitrogen molecules

    SciTech Connect

    Mazon, K. T.; Tenfen, W.; Michelin, S. E.; Arretche, F.; Lee, M.-T.; Fujimoto, M. M.

    2010-09-15

    We present a systematic study of low-energy positron collision with nitrogen molecules. Vibrational elastic and excitation cross sections are calculated using the multichannel version of the continued fractions method in the close-coupling scheme for the positron incident energy up to 20 eV. The interaction potential is treated within the static-correlation-polarization approximation. The comparison of our calculated data with existing theoretical and experimental results is encouraging.

  10. Workshop on a Cross Section of Archean Crust

    NASA Technical Reports Server (NTRS)

    Ashwal, L. D. (Editor); Card, K. D. (Editor)

    1983-01-01

    Various topics relevant to crustal genesis, especially the relationship between Archean low - and high-grade terrains, were discussed. The central Superior Province of the Canadian Shield was studied. Here a 120 km-wide transition from subgreenschist facies rocks of the Michipicoten greenstone belt to granulite facies rocks of the Kapuskasing structural zone represents an oblique cross section through some 20 km of crust, uplifted along a northwest-dipping thrust fault.

  11. CrossFit athletes exhibit high symmetry of fundamental movement patterns. A cross-sectional study

    PubMed Central

    Tafuri, Silvio; Notarnicola, Angela; Monno, Antonello; Ferretti, Francesco; Moretti, Biagio

    2016-01-01

    Summary Background even if CrossFit training programs accounted actually more than 7500 gyms affiliated in the USA and more than 2000 in Europe and involved today more than 1 million of people, actually there were not several studies about the effect of the CrossFit on the health and sport performance. The aim of these research was to evaluate the performance in 7 fundamental movement patterns using a standardized methods, the Functional Movement Screen (FMS). Methods we enrolled three groups of athletes (age 17–40 years; >6 months of training programs): CrossFitters, body builders and professional weightlifters. FMS test was performed to all people enrolled. Scores of FMS test was examined comparing three groups. Results no differences in the three groups were showed in the mean score values of each test and in total score, except for shoulder mobility test (higher among CrossFitters) and trunk stability push-up test (higher among weightlifter). Agreement between the test performed on the two sides was higher in CrossFit groups for hurdle step (93.2%), in line lung (86%), rotary stability test (95.3%) and shoulder mobility (90.7%; p<0.001). Conclusions CrossFitters seem to have a high level of concordance in the scores achieved in bilateral test. CrossFit seems to produce marked symmetry in some fundamental movements compared to weightlifting and bodybuilding. PMID:27331045

  12. (n,α) reactions cross section research at IPPE

    NASA Astrophysics Data System (ADS)

    Khryachkov, V. A.; Bondarenko, I. P.; Kuzminov, B. D.; Semenova, N. N.; Sergachev, A. I.; Ivanova, T. A.; Giorginis, G.

    2012-02-01

    An experimental set-up based on an ionization chamber with a Frisch grid and wave form digitizer was used for (n,α) cross section measurements. Use of digital signal processing allowed us to select a gaseous cell inside the sensitive area of the ionization chamber and determine the target atoms in it with high accuracy. This kind of approach provided us with a powerful method to suppress background arising from the detector structure and parasitic reactions on the working gas components. This method is especially interesting to study neutron reactions with elements for which solid target preparation is difficult (noble gases for example). In the present experiments we used a set of working gases which contained admixtures of nitrogen, oxygen, neon, argon and boron. Fission of 238U was used as neutron flux monitor. The cross section of the (n,α) reaction for 16O, 14N, 20Ne, 36Ar, 40Ar and the yield ratio α0/α1 of 10B(n,α0) to 10B(n,α1) reactions was measured for neutron energies between 1.5 and 7 MeV. Additionally a measurement of the 50Cr(n,α) cross section using a solid chromium target is also reported.

  13. Coherent set of electron cross sections for argon

    NASA Astrophysics Data System (ADS)

    Alves, L. L.; Ferreira, C. M.

    2011-10-01

    This paper presents a coherent set of electron impact cross sections for argon (elastic momentum-transfer, inelastic for the excitation of 37 levels Ar(4s,4p,3d,5p,4d,6s) and ionization), which was recently uploaded onto the LXcat IST-Lisbon database. The cross section set was validated by comparing calculated swarm parameters (electron mobility and characteristic energy) and rate coefficients (Townsend ionization coefficient and direct + cascade excitation coefficients to the 4s and 4p states) with available experimental data, for E / N = 10-4 - 100 Td and Tg = 300, 77 K. The validation procedure involves the solution to the homogeneous two-term electron Boltzmann equation, resorting to three different solvers: (i) IST-Lisbon's (ii) BOLSIG+ (v1.2) with LXcat; (iii) BOLSIG+ (v1.23). The results obtained with these solvers are compared to evidence the importance of certain numerical features related with both the energy-grid (number of points, grid-type and maximum energy value) and the interpolation scheme adopted for the cross sections. In particular, the latter can cause a 6% variation on the values of swarm parameters at intermediate E/Ns.

  14. Neutron Capture Cross Sections for the Re/Os Clock

    SciTech Connect

    Mosconi, M.; Heil, M.; Kaeppeler, F.; Plag, R.; Voss, F.; Wisshak, K.; Mengoni, A.; Cennini, P.; Chiaveri, E.; Ferrari, A.; Fitzpatrick, L.; Herrera-Martinez, A.; Kadi, Y.; Sarchiapone, L.; Vlachoudis, V.; Wendler, H.; Aerts, G.; Andriamonje, S.; Berthoumieux, E.; Dridi, W.

    2005-05-24

    The radioactive decay of 187Re {yields} 187Os (t1/2 = 43 Gyr) is suited for dating the onset of heavy-element nucleosynthesis. The radiogenic contribution to the 187Os abundance is the difference between the natural abundance and the corresponding s-process component. This component can be obtained via the well-established {sigma}N systematics using the neighboring s-only isotope 186Os, provided the neutron-capture cross sections of both isotopes are known with sufficient accuracy. We report on a new set of experiments performed with a C6D6 detector array at the n{sub T}OF neutron spallation facility of CERN. The capture cross sections of 186Os, 187Os, and 188Os have been measured in the neutron-energy range between 1 eV and 1 MeV, and Maxwellian-averaged cross sections were deduced for the relevant thermal energies from kT=5 keV to 100 keV.

  15. Fission cross section uncertainties with the NIFFTE TPC

    NASA Astrophysics Data System (ADS)

    Sangiorgio, Samuele; Niffte Collaboration

    2014-09-01

    Nuclear data such as neutron-induced fission cross sections play a fundamental role in nuclear energy and defense applications. In recent years, understanding of these systems has become increasingly dependent upon advanced simulation and modeling, where uncertainties in nuclear data propagate in the expected performances of existing and future systems. It is important therefore that uncertainties in nuclear data are minimized and fully understood. For this reason, the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) uses a Time Projection Chamber (TPC) to measure energy-differential (n,f) cross sections with unprecedented precision. The presentation will discuss how the capabilities of the NIFFTE TPC allow to directly measures systematic uncertainties in fission cross sections, in particular for what concerns fission-fragment identification, and target and beam uniformity. Preliminary results from recent analysis of 238U/235U and 239Pu/235U data collected with the TPC will be presented. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  16. Energy Dependent DVCS Cross Sections from JLab Hall A

    NASA Astrophysics Data System (ADS)

    Hyde, Charles; JLab Hall A Collaboration

    2013-10-01

    In 2010, in experiments E07-007 (hydrogen target) and E08-025 (deuterium target), the Jefferson Lab Hall A collaboration measured the helicity-dependent and helicity-independent cross sections at fixed xB = 0 . 36 , at Q2 = 1 . 5 , 1 . 75 , and 2 . 0 GeV2, and at two beam energies, 4.45 and 5.55 GeV. We detected the scattered electron in the Hall A High Resolution Spectrometer (HRS-L), and the coincidence photon in an upgraded 208 element PbF2 calorimeter. Exclusivity is inferred by missing mass in the (e ,e' γ) X reaction. In the unpolarized cross sections, the | DVCS | 2 and ℜe [DVCS† BH ] terms have different kinematic dependencies on the incident beam energy. I present preliminary results on the energy-dependence of the cross sections, and discuss their sensitivity to the Generalized Parton Distributions (GPDs). US DOE, NSF, and French IN2P3 and ANR.

  17. \\ttbar and single top cross sections at the Tevatron

    SciTech Connect

    CDF, Elizaveta Shabalina for; collaborations, D0

    2012-01-01

    We present a summary of the latest measurements of the top pair and single top cross sections performed by the CDF and D0 collaborations at the Fermilab Tevatron collider. The Fermilab Tevatron collider ended its run on September 30, 2011 after delivering more than 10 fb{sup -1} of p{bar p} collision data per experiment at {radical}s = 1.96 TeV. A large sample of top quarks collected by the CDF and D0 experiments allows to perform precision measurements of their production which is predicted to occur within the standard model (SM) either in pairs via strong interactions or as single top events via electroweak interactions. Such measurements represent an important test of the theoretical calculations which predict the t{bar t} and single top production cross sections with a precision of 6% to 8% and 5%, respectively. Precise measurements of top pair cross section ({sigma}{sub t{bar t}}) in different t{bar t} final states and single top production via different production mechanisms are highly desirable as they are sensitive to the non-SM particles that may appear in top quark production or decays.

  18. Deuterium target data for precision neutrino-nucleus cross sections

    DOE PAGESBeta

    Meyer, Aaron S.; Betancourt, Minerba; Gran, Richard; Hill, Richard J.

    2016-06-23

    Amplitudes derived from scattering data on elementary targets are basic inputs to neutrino-nucleus cross section predictions. A prominent example is the isovector axial nucleon form factor, FA(q2), which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of FA from neutrino-deuteron scattering data rely on a dipole shape assumption that introduces an unquantified error. A new analysis of world data for neutrino-deuteron scattering is performed using a model-independent, and systematically improvable, representation of FA. A complete error budget for the nucleon isovector axial radius leads to rA2 = 0.46(22)fm2, with a much larger uncertainty than determined inmore » the original analyses. The quasielastic neutrino-neutron cross section is determined as σ(νμn → μ-p)|Ev=1GeV = 10.1(0.9)×10-39cm2. The propagation of nucleon-level constraints and uncertainties to nuclear cross sections is illustrated using MINERvA data and the GENIE event generator. Furthermore, these techniques can be readily extended to other amplitudes and processes.« less

  19. Electron impact multiple ionization cross sections of heavy ions

    NASA Astrophysics Data System (ADS)

    Zeng, Jiaolong; Liu, Pengfei; Dai, Jiayu; Yuan, Jianmin

    2014-05-01

    Cross sections of electron impact ionization are important in modeling both astrophysical and laboratory plasmas. For heavy ions, accurate determination of this microscopic physical quantity is difficult due to the complex atomic structure. At high incident electron energy, inner-shell excitation and ionization processes can occur, which will result in complicated decay including Auger and radiative decay processes. For deep inner-shell excitation and ionization, cascaded Auger processes are very likely. Under conditions of collisional ionization equilibrium, the balance of electron-ion recombination and electron impact single ionization determines the charge state distribution (CSD). Accurate CSD, which in turn determined by accurate cross sections, is very important in a wide regime of spectroscopic diagnostics to infer the physical conditions of plasmas such as the electron temperature, electron density, and elemental abundance. As an illustrative example, the cross sections from the ground configuration of Sn13+ in forming Sn13+, -Sn16+ are reported in detail. The contributions from the electron impact excitation, electron impact ionization and resonant excitation processes are included.

  20. Three Dimensional Cross-Sectional Properties From Bone Densitometry

    NASA Technical Reports Server (NTRS)

    Cleek, Tammy M.; Whalen, Robert T.; Dalton, Bonnie P. (Technical Monitor)

    2001-01-01

    Bone densitometry has previously been used to obtain cross-sectional properties of bone in a single scan plane. Using three non-coplanar scans, we have extended the method to obtain the principal area Moments of inertia and orientations of the principal axes at each cross-section along the length of the scan. Various 5 aluminum phantoms were used to examine scanner characteristics to develop the highest accuracy possible for in vitro non-invasive analysis of mass distribution. Factors considered included X-ray photon energy, initial scan orientation, the included angle of the 3 scans, and Imin/Imax ratios. Principal moments of inertia were accurate to within 3.1% and principal angles were within 1 deg. of the expected value for phantoms scanned with included angles of 60 deg. and 90 deg. at the higher X-ray photon energy. Low standard deviations in error also 10 indicate high precision of calculated measurements with these included angles. Accuracy and precision decreased slightly when the included angle was reduced to 30 deg. The method was then successfully applied to a pair of excised cadaveric tibiae. The accuracy and insensitivity of the algorithms to cross-sectional shape and changing isotropy (Imin/Imax) values when various included angles are used make this technique viable for future in vivo studies.

  1. A study of radar cross section measurement techniques

    NASA Astrophysics Data System (ADS)

    McDonald, Malcolm W.

    1986-11-01

    Past, present, and proposed future technologies for the measurement of radar cross section were studied. The purpose was to determine which method(s) could most advantageously be implemented in the large microwave anechoic chamber facility which is operated at the antenna test range site. The progression toward performing radar cross section measurements of space vehicles with which the Orbital Maneuvering Vehicle will be called upon to rendezvous and dock is a natural outgrowth of previous work conducted in recent years of developing a high accuracy range and velocity sensing radar system. The radar system was designed to support the rendezvous and docking of the Orbital Maneuvering Vehicle with various other space vehicles. The measurement of radar cross sections of space vehicles will be necessary in order to plan properly for Orbital Maneuvering Vehicle rendezvous and docking assignments. The methods which were studied include: standard far-field measurements; reflector-type compact range measurements; lens-type compact range measurement; near field/far field transformations; and computer predictive modeling. The feasibility of each approach is examined.

  2. Summary of the Workshop on Neutron Cross Section Covariances

    SciTech Connect

    Smith, Donald L.

    2008-12-15

    A Workshop on Neutron Cross Section Covariances was held from June 24-27, 2008, in Port Jefferson, New York. This Workshop was organized by the National Nuclear Data Center, Brookhaven National Laboratory, to provide a forum for reporting on the status of the growing field of neutron cross section covariances for applications and for discussing future directions of the work in this field. The Workshop focused on the following four major topical areas: covariance methodology, recent covariance evaluations, covariance applications, and user perspectives. Attention was given to the entire spectrum of neutron cross section covariance concerns ranging from light nuclei to the actinides, and from the thermal energy region to 20 MeV. The papers presented at this conference explored topics ranging from fundamental nuclear physics concerns to very specific applications in advanced reactor design and nuclear criticality safety. This paper provides a summary of this workshop. Brief comments on the highlights of each Workshop contribution are provided. In addition, a perspective on the achievements and shortcomings of the Workshop as well as on the future direction of research in this field is offered.

  3. Deuterium target data for precision neutrino-nucleus cross sections

    NASA Astrophysics Data System (ADS)

    Meyer, Aaron S.; Betancourt, Minerba; Gran, Richard; Hill, Richard J.

    2016-06-01

    Amplitudes derived from scattering data on elementary targets are basic inputs to neutrino-nucleus cross section predictions. A prominent example is the isovector axial nucleon form factor, FA(q2), which controls charged current signal processes at accelerator-based neutrino oscillation experiments. Previous extractions of FA from neutrino-deuteron scattering data rely on a dipole shape assumption that introduces an unquantified error. A new analysis of world data for neutrino-deuteron scattering is performed using a model-independent, and systematically improvable, representation of FA. A complete error budget for the nucleon isovector axial radius leads to rA2=0.46 (22 ) fm2 , with a much larger uncertainty than determined in the original analyses. The quasielastic neutrino-neutron cross section is determined as σ (νμn →μ-p )|Eν=1GeV=10.1 (0.9 )×10-39 cm2 . The propagation of nucleon-level constraints and uncertainties to nuclear cross sections is illustrated using MINERvA data and the GENIE event generator. These techniques can be readily extended to other amplitudes and processes.

  4. A study of radar cross section measurement techniques

    NASA Technical Reports Server (NTRS)

    Mcdonald, Malcolm W.

    1986-01-01

    Past, present, and proposed future technologies for the measurement of radar cross section were studied. The purpose was to determine which method(s) could most advantageously be implemented in the large microwave anechoic chamber facility which is operated at the antenna test range site. The progression toward performing radar cross section measurements of space vehicles with which the Orbital Maneuvering Vehicle will be called upon to rendezvous and dock is a natural outgrowth of previous work conducted in recent years of developing a high accuracy range and velocity sensing radar system. The radar system was designed to support the rendezvous and docking of the Orbital Maneuvering Vehicle with various other space vehicles. The measurement of radar cross sections of space vehicles will be necessary in order to plan properly for Orbital Maneuvering Vehicle rendezvous and docking assignments. The methods which were studied include: standard far-field measurements; reflector-type compact range measurements; lens-type compact range measurement; near field/far field transformations; and computer predictive modeling. The feasibility of each approach is examined.

  5. Hydrogen and Nitrogen Broadened Ethane and Propane Absorption Cross Sections

    NASA Astrophysics Data System (ADS)

    Hargreaves, Robert J.; Appadoo, Dominique; Billinghurst, Brant E.; Bernath, Peter F.

    2015-06-01

    High-resolution infrared absorption cross sections are presented for the ν9 band of ethane (C2H6) at 823 cm-1. These cross sections make use of spectra recorded at the Australian Synchrotron using a Fourier transform infrared spectrometer with maximum resolution of 0.00096 cm-1. The spectra have been recorded at 150, 120 and 90 K for hydrogen and nitrogen broadened C2H6. They cover appropriate temperatures, pressures and broadening gases associated with the atmospheres of the Outer Planets and Titan, and will improve atmospheric retrievals. The THz/Far-IR beamline at the Australian Synchrotron is unique in combining a high-resolution Fourier transform spectrometer with an 'enclosive flow cooling' (EFC) cell designed to study molecules at low temperatures. The EFC cell is advantageous at temperatures for which the vapor pressure is very low, such as C2H6 at 90 K. Hydrogen broadened absorption cross sections of propane between 700 and 1200 cm-1 will also be presented based on spectra obtained at the Canadian Light Source.

  6. Towards Reliable Cross Sections for National Security Applications

    SciTech Connect

    Escher, J E; Dietrich, F S; Nobre, G A; Thompson, I J

    2011-02-24

    Stockpile stewardship requires the description of weapons performance without resorting to underground nuclear testing. In the earlier tests, selected isotopes were used as detectors, and recovered after irradiation. Aspects of nuclear device performance were inferred by comparing the measured isotopic ratios to those predicted from simulations. The reaction flows that produce the final isotopic distributions proceed through regions of the nuclear chart that include unstable nuclei. Presently, improved nuclear data input is required to reanalyze prior tests and to certify the stockpile's reliability and safety. Many important cross sections are unknown, as is shown in the example of the Yttrium reaction network (Figure 1). The relevant reactions include (n,2n), (n,n'), (n,gamma), (n,p) and other charged-particle emitting reactions. The cross sections have to be calculated or inferred from indirect measurements. In both cases, reliable optical models that are valid a few nucleons away from stability are needed. The UNEDF Nuclear Reaction activities address this need by combining nuclear-structure input from UNEDF structure calculations with modern reaction theory and large-scale computational capabilities to develop microscopic nucleon-nucleus optical potentials that can be extrapolated to unstable nuclei. In addition, the reaction calculation tools and optical models developed in this context are proving valuable for planning and interpreting indirect (surrogate) measurements of the required cross sections.

  7. Radiation pressure cross sections of model fluffy interstellar particles

    NASA Astrophysics Data System (ADS)

    Saija, R.; Iatì, M. A.; Giusto, A.; Denti, P.; Borghese, F.; Cecchi-Pestellini, C.; Aiello, S.; Barsella, B.

    Radiation presssure forces affect the dynamical behaviour of dust particles in several astrophysical environments. For a given grain mass and composition, the optical response and the radiation pressure cross sections are critically dependent on morphology. It is likely that interstellar grains take their origin from aggregation of small particles thus resulting in more or less fluffy aggregates. These kind of structures have been widely exploited in the literature by the use of approximate methods (effective medium theories). In this work we computed the radiation pressure cross sections of composite fluffy grains through the transition matrix method considering silicates aggregates made up of a large number of spherical subunits (up to 200). The results obtained, without resorting to any approximation, show that radiation pressure cross sections decrease with increasing particles fluffiness in the near UV-visible range of the spectrum. This is due to the decrease of the corresponding strenght of the multiple scattering processes that couple the aggregated spheres to each other. As a result, the inertial response to radiation forces of highly porous aggregates tends to become similar to that of the constituents particles. These conclusions are in substantial agreement with the results obtained by Mukai et al.(Astron. Astrophys. 262, 315 (1992)). For an analysis of the dynamical behaviour (expulsion from galaxies) of small aggregates see the results presented in this meeting by S. Aiello et al..

  8. Stripping Cross Sections of Fast Ions in Ion-Atom

    NASA Astrophysics Data System (ADS)

    Kecskemeti, S. R.; Kaganovich, I. D.; Startsev, E. A.; Davidson, R. C.

    2004-11-01

    Knowledge of ion-atom ionization cross sections is of great importance for many accelerator applications. We have recently investigated theoretically and experimentally the stripping of more than 18 different pairs of projectile and target particles in the range of 3-38 MeV/amu to study the range of validity of both the Born approximation and the classical trajectory calculation. In most cases, both approximations give similar results. However, for fast projectile velocities and low ionization potentials, the classical approach is not valid and can overestimate the stripping cross sections by neutral atoms by an order-of-magnitude [1]. Therefore, a hybrid approach has been developed, which automatically chooses between the Born approximation and the classical mechanics approximation depending on the parameters of the collision. When experimental data and theoretical calculations are not available, approximate formulas are frequently used. Based on experimental data and theoretical predictions, a new fit formula for ionization cross sections by fully stripped ions is proposed. [1] I. D. Kaganovich, E. A. Startsev and R. C. Davidson, Phys. Rev. A 68, 022707 (2003). [2] I. D. Kaganovich, E. A. Startsev and R. C. Davidson, Physics of Plasmas 11, 1229 (2004).

  9. Cross Section and Analyzing Power Measurements for Neutron Scattering from Aluminum and Cobalt and Spin - Cross Section Calculations

    NASA Astrophysics Data System (ADS)

    Nagadi, Mahmoud Mohamud

    Differential cross sections and analyzing power data have been measured for ^{27} Al and ^{59}Co at 15.5 MeV. Cross section data was also measured for ^{59}Co at 10, 12, 14, 17, and 19 MeV using standard time-of-flight techniques at the Triangle Universities Nuclear Laboratory (TUNL). Absolute normalization of the sigma(theta) data was performed using n-p scattering measurements. Both sigma(theta) and rm A_{y}(theta) were corrected for finite geometry, attenuation, relative efficiency, and multiple scattering effects using Monte Carlo techniques. A large data base was formed from our data and the existing data on ^{27}Al and ^{59}Co. This data base was used to develop a Dispersive Optical Model (DOM) and a Coupled Channels Model (CCM). The DOM model describes the data quite well above 8 MeV for ^{27 }Al and ^{59}Co. However, for data below 8 MeV the model is not as satisfactory, perhaps because of angular momentum l-dependencies in the absorptive potential. The CCM improved the description of the data over the DOM, but still does not describe the data well at low energies. The DOM and CCM for ^{27} Al and ^{59}Co were used to describe the spin-spin cross section data for ^{27}Al and ^{59}Co. We obtained a good fit for the spin-spin cross section with both the DOM and CCM with the spin-spin real surface parameters of V _{rm ss} = 0.80 MeV, r _{rm ss} = 1.00 fm and a _{rm ss} = 0.654 for both ^{27}Al and ^{59}Co. A surprising relation between the spin-spin cross section and the derivative of the total cross section with respect to energy, was discovered: sigma_{ss } = c {dsigma_{T} over dE} where c is a constant related to the slope of the real central potential and spin-spin potential strength. This observation is not yet understood.

  10. Wavelengths, f-Values, and Cross Sections in the UV Spectra of Astrophysical Atoms, Ions, and Molecules

    NASA Technical Reports Server (NTRS)

    Crane, Phil (Technical Monitor); Raymond, John C.; Parkinson, W. H.

    2004-01-01

    Contents include the following: Improved UV wavelengths, energy levels, and f-values for iron group ions. Update of Kurucz database of wavelengths and f-values. Publication of improved UV photodissociation cross sections for H2O. UV photoabsorption cross sections for CO bands. Service Activities and Data Outreach.

  11. Anatomy of Teaching Anatomy: Do Prosected Cross Sections Improve Students Understanding of Spatial and Radiological Anatomy?

    PubMed Central

    Vithoosan, S.; Kokulan, S.; Dissanayake, M. M.; Dissanayake, Vajira; Jayasekara, Rohan

    2016-01-01

    Introduction. Cadaveric dissections and prosections have traditionally been part of undergraduate medical teaching. Materials and Methods. Hundred and fifty-nine first-year students in the Faculty of Medicine, University of Colombo, were invited to participate in the above study. Students were randomly allocated to two age and gender matched groups. Both groups were exposed to identical series of lectures regarding anatomy of the abdomen and conventional cadaveric prosections of the abdomen. The test group (n = 77, 48.4%) was also exposed to cadaveric cross-sectional slices of the abdomen to which the control group (n = 82, 51.6%) was blinded. At the end of the teaching session both groups were assessed by using their performance in a timed multiple choice question paper as well as ability to identify structures in abdominal CT films. Results. Scores for spatial and radiological anatomy were significantly higher among the test group when compared with the control group (P < 0.05, CI 95%). Majority of the students in both control and test groups agreed that cadaveric cross section may be useful for them to understand spatial and radiological anatomy. Conclusion. Introduction of cadaveric cross-sectional prosections may help students to understand spatial and radiological anatomy better. PMID:27579181

  12. A global reference for caesarean section rates (C-Model): a multicountry cross-sectional study

    PubMed Central

    Souza, JP; Betran, AP; Dumont, A; de Mucio, B; Gibbs Pickens, CM; Deneux-Tharaux, C; Ortiz-Panozo, E; Sullivan, E; Ota, E; Togoobaatar, G; Carroli, G; Knight, H; Zhang, J; Cecatti, JG; Vogel, JP; Jayaratne, K; Leal, MC; Gissler, M; Morisaki, N; Lack, N; Oladapo, OT; Tunçalp, Ö; Lumbiganon, P; Mori, R; Quintana, S; Costa Passos, AD; Marcolin, AC; Zongo, A; Blondel, B; Hernández, B; Hogue, CJ; Prunet, C; Landman, C; Ochir, C; Cuesta, C; Pileggi-Castro, C; Walker, D; Alves, D; Abalos, E; Moises, ECD; Vieira, EM; Duarte, G; Perdona, G; Gurol-Urganci, I; Takahiko, K; Moscovici, L; Campodonico, L; Oliveira-Ciabati, L; Laopaiboon, M; Danansuriya, M; Nakamura-Pereira, M; Costa, ML; Torloni, MR; Kramer, MR; Borges, P; Olkhanud, PB; Pérez-Cuevas, R; Agampodi, SB; Mittal, S; Serruya, S; Bataglia, V; Li, Z; Temmerman, M; Gülmezoglu, AM

    2016-01-01

    Objective To generate a global reference for caesarean section (CS) rates at health facilities. Design Cross-sectional study. Setting Health facilities from 43 countries. Population/Sample Thirty eight thousand three hundred and twenty-four women giving birth from 22 countries for model building and 10 045 875 women giving birth from 43 countries for model testing. Methods We hypothesised that mathematical models could determine the relationship between clinical-obstetric characteristics and CS. These models generated probabilities of CS that could be compared with the observed CS rates. We devised a three-step approach to generate the global benchmark of CS rates at health facilities: creation of a multi-country reference population, building mathematical models, and testing these models. Main outcome measures Area under the ROC curves, diagnostic odds ratio, expected CS rate, observed CS rate. Results According to the different versions of the model, areas under the ROC curves suggested a good discriminatory capacity of C-Model, with summary estimates ranging from 0.832 to 0.844. The C-Model was able to generate expected CS rates adjusted for the case-mix of the obstetric population. We have also prepared an e-calculator to facilitate use of C-Model (www.who.int/reproductivehealth/publications/maternal_perinatal_health/c-model/en/). Conclusions This article describes the development of a global reference for CS rates. Based on maternal characteristics, this tool was able to generate an individualised expected CS rate for health facilities or groups of health facilities. With C-Model, obstetric teams, health system managers, health facilities, health insurance companies, and governments can produce a customised reference CS rate for assessing use (and overuse) of CS. PMID:26259689

  13. Health Problems Among the Elderly: A Cross-Sectional Study

    PubMed Central

    Thakur, RP; Banerjee, A; Nikumb, VB

    2013-01-01

    Background: Estimates of health problems of the elderly in developing countries are required from time to time to predict trends in disease burden and plan health care for the elderly. Developing countries have a poor track record of equitable distribution of health care. Marginalized groups living in urban slums and rural villages have poor penetration of health services. Aims: To identify the geriatric health problems in samples drawn from a slum and a village, and also to explore any gender and urban–rural difference morbidity. Subject and Methods: A community-based cross-sectional study was carried out by house to house survey of all people aged over 60 years in an urban slum and a village in the field practice area of a teaching hospital. The total elderly population in these two areas was 407, with an almost equal representation from urban slum and rural area. Information (most of them self-reported) was collected in a pre-tested instrument, which has been used earlier in a World Health Organization multicentric study in India. Categorical variables were summarized by percentages. Associations were explored with odds ratio (OR) and 95% confidence intervals (CIs). Results: Female elders outnumbered the male elders; widows outnumbered widowers. Tobacco use was very high at 58.97% (240/407). Visual impairment (including uncorrected presbyopia) was the most common handicap with prevalence of 83.29% (339/407), with males more affected than females (OR = 2.52, 95% CI 1.32-4.87). Uncorrected hearing impairment was also common. Urinary complaints were also more common in males (OR = 1.68, 95% CI = 0.93-3.04). More rural elders were living alone than their urban counterpart (OR = 2.87, 95% CI 1.23-6.86). History of weight loss was higher in the rural areas, while tendency to obesity was higher in the urban areas. An appreciable number 29.2% (119/407) had unoperated cataract. Prevalence of hypertension was 30.7% (125/407); 12% (49/407) had diabetes; 7.6% (31

  14. Suicide andthe Representation of Transparency and Cross-Sections on the Rorschach

    ERIC Educational Resources Information Center

    Blatt, Sidney J.; Ritzler, Barry A.

    1974-01-01

    Rorschach protocols of all inpatients since 1960 known to have committed suicide either during or subsequent to hospitalization (n=12) are compared with the Rorschach protocols of a closely matched control group. The results suggest that the presence of transparency and cross-sectional representations is a reliable indicator of suicidal intent.…

  15. Comparing Science Process Skills of Prospective Science Teachers: A Cross-Sectional Study

    ERIC Educational Resources Information Center

    Farsakoglu, Omer Faruk; Sahin, Cigdem; Karsli, Fethiye

    2012-01-01

    This study was conducted with the purpose of examining how Prospective Science Teachers' (PST) Science Process Skills (SPS) develop according to different grades. In this study, a cross-sectional research approach in the form of a case study was used. The sample group consisted of a total number of 102 undergraduate students who were selected from…

  16. 137 and 26 Neutron Multigroup Cross Section Library with the Bondarenko Type Shielding Table.

    Energy Science and Technology Software Center (ESTSC)

    1986-02-16

    Version 00 The basic function of MGCLIB is to generate effective neutron cross section sets in either 137 or 26 group structures for use in the discrete ordinates codes ANISN-JR or DOT 3.5 or in the Monte Carlo codes KENO-IV or MULTI-KENO.

  17. Measuring and modeling the backscattering cross section of a leaf

    NASA Technical Reports Server (NTRS)

    Senior, T. B. A.; Sarabandi, K.; Ulaby, F. T.

    1987-01-01

    Leaves are a significant feature of any vegetation canopy, and for remote sensing purposes it is important to develop an effective model for predicting the scattering from a leaf. From measurements of the X band backscattering cross section of a coleus leaf in varying stages of dryness, it is shown that a uniform resistive sheet constitutes such a model for a planar leaf. The scattering is determined by the (complex) resistivity which is, in turn, entirely specified by the gravimetric moisture content of the leaf. Using an available asymptotic expression for the scattering from a rectangular resistive plate which includes, as a special case, a metallic plate whose resistivity is zero, the computed backscattering cross sections for both principal polarizations are found to be in excellent agreement with data measured for rectangular sections of leaves with different moisture contents. If the resistivity is sufficiently large, the asymptotic expressions do not differ significantly from the physical optics ones, and for naturally shaped leaves as well as rectangular sections, the physical optics approximation in conjunction with the resistive sheet model faithfully reproduces the dominant feataures of the scattering patterns under all moisture conditions.

  18. Biological maturation, body composition, and growth of female gymnasts and control groups of schoolgirls and girl swimmers, aged 8 to 14 years: a cross-sectional survey of 1064 girls.

    PubMed

    Peltenburg, A L; Erich, W B; Bernink, M J; Zonderland, M L; Huisveld, I A

    1984-02-01

    The aim of this study was primarily to investigate differences in onset and progression of puberty, body composition, and growth between groups of young female gymnasts, schoolgirls and girl swimmers, and secondly to determine the relations between the pubertal events and body composition, especially the amount of body fat, or training activities. In 1980, 1981, and 1982, 668 female gymnasts, 298 schoolgirls and 98 girl swimmers were examined. The gymnasts were subdivided into three different groups, namely, the talented, the nontalented, and the selection group. The onset of puberty and menarche was delayed in the gymnastic groups by about 1 or 2 years compared to the schoolgirls and girl swimmers. The gymnasts were on average smaller than the schoolgirls and girl swimmers. These differences became even more pronounced after the age of 10 years. This may be caused by a delayed growth spurt within the gymnastic groups in combination with self-selection. Furthermore, the gymnasts were leaner than the other two groups: the girl swimmers had a greater fat mass and a greater lean body weight, while the schoolgirls had more fat mass. Relations were found between the parameters of pubertal development and calculated fat mass and also between breast development, pubic hair growth and age, body height, body weight, and calculated lean body weight. Only in the swimming group were training hours per week related to body height, body weight, lean body weight, and pubic hair growth. PMID:6607897

  19. From ZZ to ZH : How Low Can These Cross Sections Go or Everybody, Let's Cross Section Limbo!

    SciTech Connect

    Strauss, Emanuel Alexandre

    2009-08-01

    We report on two searches performed at the D0 detector at the Fermi National Laboratory. The first is a search for Z di-boson production with a theoretical cross section of 1.4 pb. The search was performed on 2.6 fb-1 of data and contributed to the first observation of ZZ production at a hadron collider. The second is a search for a low mass Standard Model Higgs in 4.2 fb-1 of data. The Higgs boson is produced in association with a Z boson where the Higgs decays hadronically and the Z decays to two leptons. The ZZ search was performed in both the di-electron and di-muon channels. For the ZH search, we will focus on the muonic decays where we expanded the traditional coverage by considering events in which one of the two muons fails the selection requirement, and is instead reconstructed as an isolated track. We consider Higgs masses between 100 and 150 GeV, with theoretical cross sections ranging from 0.17 to 0.042 pb, and set upper limits on the ZH production cross-section at 95% confidence level.

  20. Evidence of concentration dependence of the two-photon absorption cross section: Determining the "true" cross section value

    NASA Astrophysics Data System (ADS)

    Ajami, Aliasghar; Gruber, Peter; Tromayer, Maximilian; Husinsky, Wolfgang; Stampfl, Jürgen; Liska, Robert; Ovsianikov, Aleksandr

    2015-09-01

    The two-photon absorption (2PA) phenomenon is the basis of many unique applications involving suitable chromophores as photoinitiators. Ideally the 2PA cross section should, therefore, be a unique parameter, allowing quantification and comparing 2PA capabilities of different substances. In this report, the most straightforward and widespread method, the Z-scan technique, was used for determining the 2PA cross-section values of three different synthesized photoinitiators and one laser dye as a standard. It is demonstrated that the experimentally obtained values strongly depend on the molar concentration of a measured solution. A tenfold decrease in substance concentration can lead to the doubling of the 2PA cross-section. A similar concentration dependence was confirmed for all three investigated substances. Among the crucial implications of this observed behavior is the questionable possibility to compare the 2PA characteristics of different compounds based on the values reported in the literature. An example of another important consequence of this effect extends i.e. to the calculation of the dose necessary for killing the tumor cells in 2PA-based photodynamic therapy applications. The possible factors responsible for this contra-intuitive behavior are discussed and investigated. Finally, a reliable measurement protocol for comprehensive characterization of 2PA capability of different substances is proposed. Herewith an attempt to establish a standard method, which takes into account the concentration dependence, is made. This method provides means for faultless comparison of different compounds.

  1. From ZZ to ZH: How low can these cross sections go or everybody, let's cross section limbo!

    NASA Astrophysics Data System (ADS)

    Strauss, Emanuel Alexandre

    We report on two searches performed at the DO detector at the Fermi National Laboratory. The first is a search for Z di-boson production with a theoretical cross section of 1.4 pb. The search was performed on 2.6 fb-1 of data and contributed to the first observation of ZZ production at a hadron collider. The second is a search for a low mass Standard Model Higgs in 4.2 fb-1 of data. The Higgs boson is produced in association with a Z boson where the Higgs decays hadronically and the Z decays to two leptons. The ZZ search was performed in both the di-electron and di-muon channels. For the ZH search, we will focus on the muonic decays where we expanded the traditional coverage by considering events in which one of the two muons fails the selection requirement, and is instead reconstructed as an isolated track. We consider Higgs masses between 100 and 150 GeV, with theoretical cross sections ranging from 0.17 to 0.042 pb, and set upper limits on the ZH production cross-section at 95% confidence level.

  2. Associations of food group and nutrient intake, diet quality, and meal sizes between adults and children in the same household: a cross-sectional analysis of U.S. households

    PubMed Central

    2011-01-01

    Background One might assume that individuals living in the same household have similar dietary intakes of food groups and nutrients. However, the manner in which an adult's dietary intake affects children's food consumption, diet quality (defined as meeting intake recommendations), and meal sizes is understudied to date. The objective of this study was to estimate these relationships between minor children and the female or male head of household. Methods Dietary intakes of one randomly selected child of each age group (2-5, 6-11, or 12-18 years old (n = 2,380)) and that of the female/male head of household ((HH), proxy for mother and father) using multiple 24-hour recalls from the Continuing Survey of Food Intake by Individuals (CSFII) 1994-1996 was coded to reflect food group and nutrient density (servings/grams per 1,000 kcal). Linear or logistic regression models were used to determine the association between intakes, whether individuals' diets trended toward meeting her/his intake recommendations, and whether individuals were in the highest quintile for food group densities at four distinct eating occasions (breakfast, brunch/lunch, supper/dinner, or other) in each subject group. Stata's survey commands were used to fit linear or logistic regression models and obtain adjusted regression coefficients or odds ratios. Results Associations between food group/nutrient densities were significant but weak to moderate. Adults with diets that trended toward meeting their intake recommendations doubled the odds for children to have diets that trended toward meeting the recommendations; for many meals, adults consuming in the highest quintile for food group density predicted that children's intakes were also in the highest quintile. Conclusions Female and male adults living in the same household significantly affect children's food group and nutrient intakes, diet quality, and meal sizes. There is an urgent need for in-depth analysis to elucidate the underlying

  3. Cross-section measurements for electron-impact ionization of atoms

    NASA Astrophysics Data System (ADS)

    Freund, Robert S.; Wetzel, Robert C.; Shul, Randy J.; Hayes, Todd R.

    1990-04-01

    Absolute electron-impact cross sections have been measured from 0 to 200 eV for single ionization of 16 atoms (Mg, Fe, Cu, Ag, Al, Si, Ge, Sn, Pb, P, As, Sb, Bi, S, Se, and Te) with an estimated accuracy of +/-10%. Combined with our recent measurements of He, Ne, Ar, Kr, Xe, F, Cl, Br, I, Ga, and In [Wetzel et al., Phys. Rev. A 35, 559 (1987); Hayes et al., ibid. 35, 578 (1987); Shul, Wetzel, and Freund, ibid. 39, 5588 (1989)], a set of 27 atomic single-ionization cross sections has now been measured with the same apparatus. In addition, cross sections are reported for double ionization of ten atoms and triple ionization of eight atoms. The measurements are made by crossing an electron beam with a 3-keV beam of neutral atoms, prepared by charge-transfer neutralization of a mass-selected ion beam. The critical measurement of absolute neutral beam flux is made with a calibrated pyroelectric crystal. The magnitudes of the single-ionization-peak cross sections decrease monotonically across rows of the periodic table from group IIIA (Al,Ga,In) to group VIIIA (Ar,Kr,Xe), varying much more than predicted by various empirical formulas and classical and quantum-mechanical theories.

  4. Autism Symptoms across Adulthood in Men with Fragile X Syndrome: A Cross-Sectional Analysis

    ERIC Educational Resources Information Center

    Hartley, Sigan L.; Wheeler, Anne C.; Mailick, Marsha R.; Raspa, Melissa; Mihaila, Iulia; Bishop, Ellen; Bailey, Donald B.

    2015-01-01

    A cross-sectional analysis was used to examine age-related differences in ASD symptoms and corresponding differences in disruptive behavior and social skills in 281 adult men with fragile X syndrome. Four age groups were created: 18-21, 22-29, 30-39, and 40-49 years. The 18-21 year-old group was reported to have more impairments in verbal…

  5. Attachment and group psychotherapy: introduction to a special section.

    PubMed

    Tasca, Giorgio A

    2014-03-01

    The application of attachment theory to adult psychotherapy represents a growing area of research and practice. Despite the conceptual overlap between group therapeutic factors, attachment theory, and therapeutic tasks as outlined by Bowlby (1988), there is little research on attachment functioning in group therapy. Hence, there remain substantial questions about the role of attachment theory in understanding group therapy processes and outcomes. The three studies in this special section advance the research in some of these important areas, including showing that positive changes in self-reported attachment insecurity among clients persist long after group therapy ends; attachment anxiety affects the level and rate of interpersonal learning in groups; and change in attachment to the therapy group has an impact on longer term change in individual group members' attachment. Each article also examines the impact of these attachment concepts on treatment outcomes. Numerous areas remain to be explored when it comes to the implications of attachment theory for understanding and conducting group therapy, including the conceptual and practical overlap between attachment concepts such as security and exploration with group therapeutic factors such as cohesion and interpersonal learning. The articles in this special section begin to address some of these issues related to attachment theory and its implications for group therapists. PMID:24377399

  6. Radioactive targets for neutron-induced cross section measurements

    SciTech Connect

    Kronenberg, A.; Bond, E. M.; Glover, S. E.; Rundberg, R. S.; Vieira, D. J.; Esch, E. I.; Reifarth, R.; Ullmann, J. L.; Haight, Robert C.; Rochmann, D.

    2004-01-01

    Measurements using radioactive targets are important for the determination of key reaction path ways associated with the synthesis of the elements in nuclear astrophysics (sprocess), advanced fuel cycle initiative (transmutation of radioactive waste), and stockpile stewardship. High precision capture cross-section measurements are needed to interpret observations, predict elemental or isotopical ratios, and unobserved abundances. There are two new detector systems that are presently being commissioned at Los Alamos National Laboratory for very precise measurements of (n,{gamma}) and (n,f) cross-sections using small quantities of radioactive samples. DANCE (Detector for Advanced Neutron-Capture Experiments), a 4 {pi} gamma array made up of 160 BaF{sub 2} detectors, is designed to measure neutron capture cross-sections of unstable nuclei in the low-energy range (thermal to {approx}500 keV). The high granularity and high detection efficiency of DANCE, combined with the high TOF-neutron flux available at the Lujan Center provides a versatile tool for measuring many important cross section data using radioactive and isotopically enriched targets of about 1 milligram. Another powerful instrument is the Lead-slowing down spectrometer (LSDS), which will enable the measurement of neutron-induced fission cross-section of U-235m and other short-lived actinides in a energy range from 1-200 keV with sample sizes down to 10 nanograms. Due to the short half-life of the U-235m isomer (T{sub 1/2} = 26 minutes), the samples must be rapidly and repeatedly extracted from its {sup 239}Pu parent. Since {sup 239}Pu is itself highly fissile, the separation must not only be rapid, but must also be of very high purity (the Pu must be removed from the U with a decontamination factor >10{sup 12}). Once extracted and purified, the {sup 235m}U isomer would be electrodeposited on solar cells as a fission detector and placed within the LSDS for direct (n,f) cross section measurements. The

  7. Noncircular Cross Sections Could Enhance Mixing in Sprays

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Abdel-Hameed, Hesham

    2003-01-01

    A computational study has shown that by injecting drops in jets of gas having square, elliptical, triangular, or other noncircular injection cross sections, it should be possible to increase (relative to comparable situations having circular cross section) the entrainment and dispersion of liquid drops. This finding has practical significance for a variety of applications in which it is desirable to increase dispersion of drops. For example, in chemical-process sprays, increased dispersion leads to increases in chemical- reaction rates; in diesel engines, increasing the dispersion of drops of sprayed fuel reduces the production of soot; and in household and paint sprays, increasing the dispersion of drops makes it possible to cover larger surfaces. It has been known for some years that single-phase fluid jets that enter flow fields through noncircular inlets entrain more fluid than do comparable jets entering through circular inlets. The computational study reported here was directed in part toward determining whether and how this superior mixing characteristic of noncircular single phase jets translates to a similar benefit in cases of two-phase jets (that is, sprays). The study involved direct numerical simulations of single- and two-phase free jets with circular, elliptical, rectangular, square, and triangular inlet cross sections. The two-phase jets consisted of gas laden with liquid drops randomly injected at the inlets. To address the more interesting case of evaporating drops, the carrier gas in the jets was specified to be initially unvitiated by the vapor of the liquid chemical species and the initial temperature of the drops was chosen to be smaller than that of the gas. The mathematical model used in the study was constructed from the conservation equations for the two-phase flow and included complete couplings of mass, momentum, and energy based on thermodynamically self-consistent specification of the enthalpy, internal energy, and latent heat of

  8. Hadronic Production of psi(2S) Cross section and Polarization

    SciTech Connect

    Chung, Kwangzoo; /Carnegie Mellon U.

    2008-05-01

    The hadronic production cross section and the polarization of {psi}(2S) meson are measured by using the data from p{bar p} collisions at {radical}s = 1.96 TeV collected by the Collider Detector at Fermilab. The datasets used correspond to integrated luminosity of 1.1 fb{sup -1} and 800 pb{sup -1}, respectively. The decay {psi}(2S) {yields} {mu}{sup +}{mu}{sup -} is used to reconstruct {psi}(2S) mesons in the rapidity range |y({psi}(2S))| < 0.6. The coverage of the p{sub T} range is 2.0 GeV/c {le} p{sub T} ({psi}(2S)) < 30 GeV/c for the cross section analysis and pT {ge} 5 GeV/c for the polarization analysis. For events with p{sub T} ({psi}(2S)) > 2 GeV/c the integrated inclusive cross section multiplied by the branching ratio for dimuon decay is 3.17 {+-} 0.04 {+-} 0.28 nb . This result agrees with the CDF Run I measurement considering the increased center-of-mass energy from 1.8 TeV to 1.96 TeV. The polarization of the promptly produced {psi}(2S) mesons is found to be increasingly longitudinal as p{sub T} increases from 5 GeV/c to 30 GeV/c. The result is compared to contemporary theory models.

  9. Propionaldehyde infrared cross-sections and band strengths

    NASA Astrophysics Data System (ADS)

    Köroğlu, Batikan; Loparo, Zachary; Nath, Janardan; Peale, Robert E.; Vasu, Subith S.

    2015-02-01

    The use of oxygenated biofuels reduces the greenhouse gas emissions; however, they also result in increased toxic aldehyde by-products, mainly formaldehyde, acetaldehyde, acrolein, and propionaldehyde. These aldehydes are carcinogenic and/or toxic and therefore it is important to understand their formation and destruction pathways in combustion and atmospheric systems. Accurate information about their infrared cross-sections and integrated strengths are crucially needed for development of quantitative detection schemes and modeling tools. Critical to the development of such diagnostics are accurate characterization of the absorption features of these species. In this study, the gas phase infrared spectra of propionaldehyde (also called propanal, CH3-CH2-CHO), a saturated three carbon aldehyde found in the exhaust emissions of biodiesel or diesel fuels, was studied using high resolution Fourier Transform Infrared (FTIR) spectroscopy over the wavenumber range of 750-3300 cm-1 and at room temperature 295 K. The absorption cross sections of propionaldehyde were recorded at resolutions of 0.08 and 0.096 cm-1 and at seven different pressures (4-33 Torr). The calculated band-strengths were reported and the integrated band intensity results were compared with values taken from the Pacific Northwest National Laboratory (PNNL) database (showing less than 2% discrepancy). The peak positions of the 19 different vibrational bands of propionaldehyde were also compared with previous studies taken at a lower resolution of 1 cm-1. To the best of our knowledge, the current FTIR measurements provide the first highest resolution infrared cross section data for propionaldehyde.

  10. Detailed photonuclear cross-section calculations and astrophysical applications

    SciTech Connect

    Gardner, D.G.; Gardner, M.A.; Hoff, R.W.

    1989-06-15

    We have investigated the role of an isomeric state and its coupling to the ground state (g.s.) via photons and neutron inelastic scattering in a stellar environment by making detailed photonuclear and neutron cross-section calculations for /sup 176/Lu and /sup 210/Bi. In the case of /sup 176/Lu, the g.s. would function as an excellent galactic slow- (s-) process chronometer were it not for the 3.7-h isomer at 123 keV. Our calculations predicted much larger photon cross sections for production of the isomer, as well as a lower threshold, than had been assumed based on earlier measurements. These two factors combine to indicate that an enormous correction, a factor of 10/sup 7/, must be applied to shorten the current estimate of the half-life against photoexcitation of /sup 176/Lu as a function of temperature. This severely limits the use of /sup 176/Lu as a stellar chronometer and indicates a significantly lower temperature at which the two states reach thermal equilibrium. For /sup 210/Bi, our preliminary calculations of the production and destruction of the 3 /times/ 10/sup 6/ y isomeric state by neutrons and photons suggest that the /sup 210/Bi isomer may not be destroyed by photons as rapidly as assumed in certain stellar environments. This leads to an alternate production path of /sup 207/Pb and significantly affects presently interpreted lead isotopic abundances. We have been able to make such detailed nuclear cross-section calculations using: modern statistical-model codes of the Hauser-Feshbach type, with complete conservation of angular momentum and parity; reliable systematics of the input parameters required by these codes, including knowledge of the absolute gamma-ray strength-functions for E1, M1, and E2 transitions; and codes developed to compute large, discrete, nuclear level sets, their associated gamma-ray branchings, and the presence and location of isomeric states. 7 refs., 2 figs.

  11. Neutron Cross Section Covariances for Structural Materials and Fission Products

    NASA Astrophysics Data System (ADS)

    Hoblit, S.; Cho, Y.-S.; Herman, M.; Mattoon, C. M.; Mughabghab, S. F.; Obložinský, P.; Pigni, M. T.; Sonzogni, A. A.

    2011-12-01

    We describe neutron cross section covariances for 78 structural materials and fission products produced for the new US evaluated nuclear reaction library ENDF/B-VII.1. Neutron incident energies cover full range from 10 eV to 20 MeV and covariances are primarily provided for capture, elastic and inelastic scattering as well as (n,2n). The list of materials follows priorities defined by the Advanced Fuel Cycle Initiative, the major application being data adjustment for advanced fast reactor systems. Thus, in addition to 28 structural materials and 49 fission products, the list includes also 23Na which is important fast reactor coolant. Due to extensive amount of materials, we adopted a variety of methodologies depending on the priority of a specific material. In the resolved resonance region we primarily used resonance parameter uncertainties given in Atlas of Neutron Resonances and either applied the kernel approximation to propagate these uncertainties into cross section uncertainties or resorted to simplified estimates based on integral quantities. For several priority materials we adopted MF32 covariances produced by SAMMY at ORNL, modified by us by adding MF33 covariances to account for systematic uncertainties. In the fast neutron region we resorted to three methods. The most sophisticated was EMPIRE-KALMAN method which combines experimental data from EXFOR library with nuclear reaction modeling and least-squares fitting. The two other methods used simplified estimates, either based on the propagation of nuclear reaction model parameter uncertainties or on a dispersion analysis of central cross section values in recent evaluated data files. All covariances were subject to quality assurance procedures adopted recently by CSEWG. In addition, tools were developed to allow inspection of processed covariances and computed integral quantities, and for comparing these values to data from the Atlas and the astrophysics database KADoNiS.

  12. Elliptical Morphology of the Carpal Tunnel Cross Section

    PubMed Central

    Gabra, Joseph N.; Kim, Dong Hee; Li, Zong-Ming

    2015-01-01

    Summary Although the carpal tunnel is known for its anatomical constituents, its morphology is not well recognized. The aim of this study was to investigate the morphometric properties of the carpal tunnel and its surrounding structures. Magnetic resonance, cross-sectional images of the distal carpal tunnel were collected from eight cadaveric hands. Morphological analyses were performed for the cross sections of the carpal tunnel, interior carpus boundary, and exterior carpus boundary. The specimens had a carpal arch width and height of 23.9 ± 2.9 mm and 2.2 ± 0.9 mm, respectively. The carpal tunnel, interior carpus boundary, and exterior carpus boundary had perimeters of 54.8 ± 4.5 mm, 68.5 ± 7.0 mm, and 130.6 ± 11.8 mm, respectively, and areas of 183.5 ± 30.1 mm2, 240.7 ± 40.2 mm2, and 1002.3 ± 183.7 mm2, respectively. The cross sections were characterized by elliptical fitting with aspect ratios of 1.96 ± 0.15, 1.96 ± 0.19, and 1.76 ± 0.19 for the carpal tunnel, interior carpus boundary, and exterior carpus boundary, respectively. The major axis of the boundaries increased in pronation angle, relative to the hamate-trapezium axis, for the exterior carpus (6.0 ± 3.0°), interior carpus (8.2 ± 3.2°), and carpal tunnel (15.9 ± 2.2°). This study advances our understanding of the structural anatomy of the carpal tunnel, and the morphological information is valuable in the identification of structural abnormality, assistance of surgical planning, and evaluation of treatment of effects. PMID:25949095

  13. Constant cross section of loops in the solar corona

    NASA Astrophysics Data System (ADS)

    Peter, H.; Bingert, S.

    2012-12-01

    Context. The corona of the Sun is dominated by emission from loop-like structures. When observed in X-ray or extreme ultraviolet emission, these million K hot coronal loops show a more or less constant cross section. Aims: In this study we show how the interplay of heating, radiative cooling, and heat conduction in an expanding magnetic structure can explain the observed constant cross section. Methods: We employ a three-dimensional magnetohydrodynamics (3D MHD) model of the corona. The heating of the coronal plasma is the result of braiding of the magnetic field lines through footpoint motions and subsequent dissipation of the induced currents. From the model we synthesize the coronal emission, which is directly comparable to observations from, e.g., the Atmospheric Imaging Assembly on the Solar Dynamics Observatory (AIA/SDO). Results: We find that the synthesized observation of a coronal loop seen in the 3D data cube does match actually observed loops in count rate and that the cross section is roughly constant, as observed. The magnetic field in the loop is expanding and the plasma density is concentrated in this expanding loop; however, the temperature is not constant perpendicular to the plasma loop. The higher temperature in the upper outer parts of the loop is so high that this part of the loop is outside the contribution function of the respective emission line(s). In effect, the upper part of the plasma loop is not bright and thus the loop actually seen in coronal emission appears to have a constant width. Conclusions: From this we can conclude that the underlying field-line-braiding heating mechanism provides the proper spatial and temporal distribution of the energy input into the corona - at least on the observable scales. Movies associated to Figs. 1 and 2 are available in electronic form at http://www.aanda.org

  14. Mass Spectra and Ion Collision Cross Sections of Hemoglobin

    NASA Astrophysics Data System (ADS)

    Kang, Yang; Terrier, Peran; Douglas, D. J.

    2011-02-01

    Mass spectra of commercially obtained hemoglobin (Hb) show higher levels of monomer and dimer ions, heme-deficient dimer ions, and apo-monomer ions than hemoglobin freshly prepared from blood. This has previously been attributed to oxidation of commercial Hb. Further, it has been reported that that dimer ions from commercial bovine Hb have lower collision cross sections than low charge state monomer ions. To investigate these effects further, we have recorded mass spectra of fresh human Hb, commercial human and bovine Hb, fresh human Hb oxidized with H2O2, lyophilized fresh human Hb, fresh human Hb both lyophilized and chemically oxidized, and commercial human Hb oxidized with H2O2. Masses of α-monomer ions of all hemoglobins agree with the masses expected from the sequences within 3 Da or better. Mass spectra of the β chains of commercial Hb and oxidized fresh human Hb show a peak or shoulder on the high mass side, consistent with oxidation of the protein. Both commercial proteins and oxidized fresh human Hb produce heme-deficient dimers with masses 32 Da greater than expected and higher levels of monomer and dimer ions than fresh Hb. Lyophilization or oxidation of Hb both produce higher levels of monomer and dimer ions in mass spectra. Fresh human Hb, commercial human Hb, commercial bovine Hb, and oxidized commercial human Hb all give dimer ions with cross sections greater than monomer ions. Thus, neither oxidation of Hb or the difference in sequence between human and bovine Hb make substantial differences to cross sections of ions.

  15. Neutron Cross Section Covariances for Structural Materials and Fission Products

    SciTech Connect

    Hoblit, S.; Hoblit,S.; Cho,Y.-S.; Herman,M.; Mattoon,C.M.; Mughabghab,S.F.; Oblozinsky,P.; Pigni,M.T.; Sonzogni,A.A.

    2011-12-01

    We describe neutron cross section covariances for 78 structural materials and fission products produced for the new US evaluated nuclear reaction library ENDF/B-VII.1. Neutron incident energies cover full range from 10{sup -5} eV to 20 MeV and covariances are primarily provided for capture, elastic and inelastic scattering as well as (n,2n). The list of materials follows priorities defined by the Advanced Fuel Cycle Initiative, the major application being data adjustment for advanced fast reactor systems. Thus, in addition to 28 structural materials and 49 fission products, the list includes also {sup 23}Na which is important fast reactor coolant. Due to extensive amount of materials, we adopted a variety of methodologies depending on the priority of a specific material. In the resolved resonance region we primarily used resonance parameter uncertainties given in Atlas of Neutron Resonances and either applied the kernel approximation to propagate these uncertainties into cross section uncertainties or resorted to simplified estimates based on integral quantities. For several priority materials we adopted MF32 covariances produced by SAMMY at ORNL, modified by us by adding MF33 covariances to account for systematic uncertainties. In the fast neutron region we resorted to three methods. The most sophisticated was EMPIRE-KALMAN method which combines experimental data from EXFOR library with nuclear reaction modeling and least-squares fitting. The two other methods used simplified estimates, either based on the propagation of nuclear reaction model parameter uncertainties or on a dispersion analysis of central cross section values in recent evaluated data files. All covariances were subject to quality assurance procedures adopted recently by CSEWG. In addition, tools were developed to allow inspection of processed covariances and computed integral quantities, and for comparing these values to data from the Atlas and the astrophysics database KADoNiS.

  16. Cross sections and reaction rates of relevance to aeronomy

    SciTech Connect

    Fox, J.L. )

    1991-01-01

    Experimental and theoretical data relevant to models and measurements of the chemical and thermal structures and luminosity of the thermospheres of the earth and planets published during the last four years are surveyed. Among chemical processes, attention is given to ion-molecule reactions, dissociative recombination of molecular ions, and reactions between neutral species. Both reactions between ground state species and species in excited states are considered, including energy transfer and quenching. Measured and calculated cross sections for interactions of solar radiation with atmospheric species, such as photoabsorption, photoionization, and photodissociation and related processes are surveyed.

  17. Cross-sectional Imaging Review of Tuberous Sclerosis.

    PubMed

    Krishnan, Anant; Kaza, Ravi K; Vummidi, Dharshan R

    2016-05-01

    Tuberous sclerosis complex (TSC) is a multisystem, genetic disorder characterized by development of hamartomas in the brain, abdomen, and thorax. It results from a mutation in one of 2 tumor suppressor genes that activates the mammalian target of rapamycin pathway. This article discusses the origins of the disorder, the recently updated criteria for the diagnosis of TSC, and the cross-sectional imaging findings and recommendations for surveillance. Familiarity with the diverse radiological features facilitates diagnosis and helps in treatment planning and monitoring response to treatment of this multisystem disorder. PMID:27153781

  18. An accelerator test of semi-empirical cross-sections

    NASA Technical Reports Server (NTRS)

    Lau, K. H.; Mewaldt, R. A.; Wiedenbeck, M. E.

    1983-01-01

    Experimentally measured yields of isotopes of elements from Mg-12 to K-19 resulting from the fragmentation of Ar-40 are compared with calculated yields based on semiempirical cross-section formulae. The measurements, made at the LBL Bevalac using a beam of 287 MeV/amu Ar-40 incident on a CH2 target, achieve excellent mass resolution (up to 0.2 amu) through the use of a Si(Li) detector telescope. The general agreement between calculation and experiment is good (rms difference of about 24 percent), but some significant differences are reported.

  19. Comprehensive Nuclear Model Code, Nucleons, Ions, Induced Cross-Sections

    Energy Science and Technology Software Center (ESTSC)

    2002-09-27

    EMPIRE-II is a flexible code for calculation of nuclear reactions in the frame of combined op0tical, Multistep Direct (TUL), Multistep Compound (NVWY) and statistical (Hauser-Feshbach) models. Incident particle can be a nucleon or any nucleus (Heavy Ion). Isomer ratios, residue production cross sections and emission spectra for neutrons, protons, alpha- particles, gamma-rays, and one type of Light Ion can be calculated. The energy range starts just above the resonance region for neutron induced reactions andmore » extends up to several hundreds of MeV for the Heavy Ion induced reactions.« less

  20. Proton radiography, nuclear cross sections and multiple Coulomb scattering

    SciTech Connect

    Sjue, Sky K.

    2015-11-04

    The principles behind proton radiography including multiple Coulomb scattering are discussed for a purely imaginary square well nucleus in the eikonal approximation. It is found that a very crude model can reproduce the angular dependence of the cross sections measured at 24 GeV/c. The largest differences are ~3% for the 4.56 mrad data, and ~4% for the 6.68 mrad data. The prospect of understanding how to model deterministically high-energy proton radiography over a very large range of energies is promising, but it should be tested more thoroughly.