Proton-Nucleus Elastic Cross Sections Using Two-Body In-Medium Scattering Amplitudes
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.
2001-01-01
Recently, a method was developed of extracting nucleon-nucleon (NN) cross sections in the medium directly from experiment. The in-medium NN cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. The ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium NN cross sections to calculate elastic proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.
Proton-Nucleus Total Cross Sections in Coupled-Channel Approach
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Wilson, John W.; Cucinotta, Francis A.
2000-01-01
Recently, nucleon-nucleon (N-N) cross sections in the medium have been extracted directly from experiment. The in-medium N-N cross sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the Langley Research Center. In the present study the ratio of the real to the imaginary part of the two-body scattering amplitude in the medium was investigated. These ratios are used in combination with the in-medium N-N cross sections to calculate total proton-nucleus cross sections. The agreement is excellent with the available experimental data. These cross sections are needed for the radiation risk assessment of space missions.
Client Assessment in an Industrial Setting: A Cross-Sectional Method.
ERIC Educational Resources Information Center
Yamatani, Hide
1988-01-01
Used cross-sectional method for evaluating social service programs in industrial setting to estimate numbers of workers needing social services, levels of program use, and penetration and to examine program outcome. Workers served by social service or employee assistance programs can be examined to determine additional services needed, adequacy of…
Subtraction method of computing QCD jet cross sections at NNLO accuracy
NASA Astrophysics Data System (ADS)
Trócsányi, Zoltán; Somogyi, Gábor
2008-10-01
We present a general subtraction method for computing radiative corrections to QCD jet cross sections at next-to-next-to-leading order accuracy. The steps needed to set up this subtraction scheme are the same as those used in next-to-leading order computations. However, all steps need non-trivial modifications, which we implement such that that those can be defined at any order in perturbation theory. We give a status report of the implementation of the method to computing jet cross sections in electron-positron annihilation at the next-to-next-to-leading order accuracy.
Exclusive Reactions Involving Pions and Nucleons
NASA Technical Reports Server (NTRS)
Norbury, John W.; Blattnig, Steve R.; Tripathi, R. K.
2002-01-01
The HZETRN code requires inclusive cross sections as input. One of the methods used to calculate these cross sections requires knowledge of all exclusive processes contributing to the inclusive reaction. Conservation laws are used to determine all possible exclusive reactions involving strong interactions between pions and nucleons. Inclusive particle masses are subsequently determined and are needed in cross-section calculations for inclusive pion production.
Cross sections for n+{sup 14}N from an R-matrix analysis of the {sup 15}N system
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hale, G.M.; Young, P.G.; Chadwick, M.B.
1994-06-01
As part of the Hiroshima-Nagasaki Dose Reevaluation Program, a new evaluation of the neutron cross sections for {sup 14}N was made for ENDF/B-VI, based at energies below 2.5 MeV on a multichannel R-matrix analysis of reactions in the {sup 15}N system. The types of data used in the analysis, and the resulting cross sections and resonance structure for {sup 15}N are briefly described. The resonant features of the neutron cross sections were especially well determined by including precise, high-resolution neutron total cross section measurements from ORNL. While the new evaluated cross section appear to be significant improvements over the earliermore » ones, they still need to be tested more extensively against recent measurements of the differential elastic cross section from Oak Ridge.« less
Simple, empirical approach to predict neutron capture cross sections from nuclear masses
DOE Office of Scientific and Technical Information (OSTI.GOV)
Couture, Aaron Joseph; Casten, Richard F.; Cakirli, R. B.
Here, neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40%, and has limited predictive power, with predictions from different models rapidly differing by an order ofmore » magnitude a few nucleons from the last measurement.« less
Simple, empirical approach to predict neutron capture cross sections from nuclear masses
Couture, Aaron Joseph; Casten, Richard F.; Cakirli, R. B.
2017-12-20
Here, neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40%, and has limited predictive power, with predictions from different models rapidly differing by an order ofmore » magnitude a few nucleons from the last measurement.« less
FY16 Status Report on NEAMS Neutronics Activities
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, C. H.; Shemon, E. R.; Smith, M. A.
2016-09-30
The goal of the NEAMS neutronics effort is to develop a neutronics toolkit for use on sodium-cooled fast reactors (SFRs) which can be extended to other reactor types. The neutronics toolkit includes the high-fidelity deterministic neutron transport code PROTEUS and many supporting tools such as a cross section generation code MC 2-3, a cross section library generation code, alternative cross section generation tools, mesh generation and conversion utilities, and an automated regression test tool. The FY16 effort for NEAMS neutronics focused on supporting the release of the SHARP toolkit and existing and new users, continuing to develop PROTEUS functions necessarymore » for performance improvement as well as the SHARP release, verifying PROTEUS against available existing benchmark problems, and developing new benchmark problems as needed. The FY16 research effort was focused on further updates of PROTEUS-SN and PROTEUS-MOCEX and cross section generation capabilities as needed.« less
Excitation of vibrational quanta in furfural by intermediate-energy electrons
NASA Astrophysics Data System (ADS)
Jones, D. B.; Neves, R. F. C.; Lopes, M. C. A.; da Costa, R. F.; Varella, M. T. do N.; Bettega, M. H. F.; Lima, M. A. P.; García, G.; Blanco, F.; Brunger, M. J.
2015-12-01
We report cross sections for electron-impact excitation of vibrational quanta in furfural, at intermediate incident electron energies (20, 30, and 40 eV). The present differential cross sections are measured over the scattered electron angular range 10°-90°, with corresponding integral cross sections subsequently being determined. Furfural is a viable plant-derived alternative to petrochemicals, being produced via low-temperature plasma treatment of biomass. Current yields, however, need to be significantly improved, possibly through modelling, with the present cross sections being an important component of such simulations. To the best of our knowledge, there are no other cross sections for vibrational excitation of furfural available in the literature, so the present data are valuable for this important molecule.
A method for calculating proton-nucleus elastic cross-sections
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.
2002-01-01
Recently [Nucl. Instr. and Meth. B 145 (1998) 277; Extraction of in-medium nucleon-nucleon amplitude from experiment, NASA-TP, 1998], we developed a method of extracting nucleon-nucleon (N-N) cross-sections in the medium directly from experiment. The in-medium N-N cross-sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the NASA Langley Research Center. We investigated [Proton-nucleus total cross-sections in coupled-channel approach, NASA/TP, 2000; Nucl. Instr. and Meth. B 173-174 (2001) 391] the ratio of real to imaginary part of the two body scattering amplitude in the medium. These ratios are used in combination with the in-medium N-N cross-sections to calculate proton-nucleus elastic cross-sections. The agreement is excellent with the available experimental data. These cross-sections are needed for the radiation risk assessment of space missions. c2002 Elsevier Science B.V. All rights reserved.
NASA Astrophysics Data System (ADS)
Shakhatov, V. A.; Lebedev, Yu. A.
2018-01-01
A review is given of experimental and theoretical data on the cross sections for ionization, excitation, and deexcitation of atomic hydrogen. The set of the cross sections required to calculate the electron energy distribution function and find the level-to-level rate coefficients needed to solve balance equations for the densities of neutral and charged particles in hydrogen plasma is determined.
Medium modified two-body scattering amplitude from proton-nucleus total cross-sections
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Wilson, J. W.; Cucinotta, F. A.
2001-01-01
Recently (R.K. Tripathi, J.W. Wilson, F.A. Cucinotta, Nucl. Instr. and Meth. B 145 (1998) 277; R.K. Tripathi, F.A. Cucinotta, J.W. Wilson, NASA-TP-1998-208438), we have extracted nucleon-nucleon (N-N) cross-sections in the medium directly from experiment. The in-medium N-N cross-sections form the basic ingredients of several heavy-ion scattering approaches including the coupled-channel approach developed at the NASA Langley Research Center. Here, we investigate the ratio of real to imaginary part of the two-body scattering amplitude in the medium. These ratios are used in combination with the in-medium N-N cross-sections to calculate total proton-nucleus cross-sections. The agreement is excellent with the available experimental data. These cross-sections are needed for the radiation risk assessment of space missions. c2001 Elsevier Science B.V. All rights reserved.
Pion polarizabilities from a γ γ → π π analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dai, Ling -Yun; Pennington, Michael R.
Here, we present results for pion polarizabilities predicted using dispersion relations from our earlier Amplitude Analysis of world data on two photon production of meson pairs. The helicity-zero polarizabilities are rather stable and insensitive to uncertainties in cross-channel exchanges. The need is first to confirm the recent result onmore » $$(\\alpha_1-\\beta_1)$$ for the charged pion by COMPASS at CERN to an accuracy of 10% by measuring the $$\\gamma\\gamma\\to\\pi^+\\pi^-$$ cross-section to an uncertainty of ~1\\%. Then the same polarizability, but for the $$\\pi^0$$, is fixed to be $$(\\alpha_1-\\beta_1)_{\\pi^0}=(0.9\\pm0.2)\\times 10^{-4}$$ fm$$^{3}$$. By analyzing the correlation between uncertainties in the meson polarizability and those in $$\\gamma\\gamma$$ cross-sections, we suggest experiments need to measure these cross-sections between $$\\sqrt{s}\\simeq 350$$ and 600~MeV. The $$\\pi^0\\pi^0$$ cross-section then makes the $$(\\alpha_2-\\beta_2)_{\\pi^0}$$ the easiest helicity-two polarizability to determine.« less
Pion polarizabilities from a γ γ → π π analysis
Dai, Ling -Yun; Pennington, Michael R.
2016-12-30
Here, we present results for pion polarizabilities predicted using dispersion relations from our earlier Amplitude Analysis of world data on two photon production of meson pairs. The helicity-zero polarizabilities are rather stable and insensitive to uncertainties in cross-channel exchanges. The need is first to confirm the recent result onmore » $$(\\alpha_1-\\beta_1)$$ for the charged pion by COMPASS at CERN to an accuracy of 10% by measuring the $$\\gamma\\gamma\\to\\pi^+\\pi^-$$ cross-section to an uncertainty of ~1\\%. Then the same polarizability, but for the $$\\pi^0$$, is fixed to be $$(\\alpha_1-\\beta_1)_{\\pi^0}=(0.9\\pm0.2)\\times 10^{-4}$$ fm$$^{3}$$. By analyzing the correlation between uncertainties in the meson polarizability and those in $$\\gamma\\gamma$$ cross-sections, we suggest experiments need to measure these cross-sections between $$\\sqrt{s}\\simeq 350$$ and 600~MeV. The $$\\pi^0\\pi^0$$ cross-section then makes the $$(\\alpha_2-\\beta_2)_{\\pi^0}$$ the easiest helicity-two polarizability to determine.« less
NASA Astrophysics Data System (ADS)
Metusala, D.
2017-07-01
This alternative method provides a simple and faster procedure for preparing cross-sections of leaves and roots in herbaceous plants, especially for living specimens of orchids (Orchidaceae). This method used a clamp-on hand sliding microtome to make cross-sections of leaves and roots, with sections preserved inside the microtubes containing preservation liquid. This preservation technique allowed the sections to be restained and to be used for further usage in future. This method was more practical than the paraffin embedding method because it does not need the additional steps of paraffin embedding and deparaffinization. It may also provide better cross-section results than free-hand sectioning method. The procedure is very feasible and is recommended for use in plant anatomy observation.
Scaling Cross Sections for Ion-atom Impact Ionization
DOE Office of Scientific and Technical Information (OSTI.GOV)
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,more » and so forth) are discussed using, as examples, the ionization cross sections of hydrogen and helium atoms by various fully stripped ions.« less
Fusion materials high energy-neutron studies. A status report
DOE Office of Scientific and Technical Information (OSTI.GOV)
Doran, D.G.; Guinan, M.W.
1980-01-01
The objectives of this paper are (1) to provide background information on the US Magnetic Fusion Reactor Materials Program, (2) to provide a framework for evaluating nuclear data needs associated with high energy neutron irradiations, and (3) to show the current status of relevant high energy neutron studies. Since the last symposium, the greatest strides in cross section development have been taken in those areas providing FMIT design data, e.g., source description, shielding, and activation. In addition, many dosimetry cross sections have been tentatively extrapolated to 40 MeV and integral testing begun. Extensive total helium measurements have been made inmore » a variety of neutron spectra. Additional calculations are needed to assist in determining energy dependent cross sections.« less
Measuring excitation functions needed to interpret cosmogenic nuclide production in lunar rocks
NASA Technical Reports Server (NTRS)
Sisterson, J. M.; Kim, K.; Beverding, A.; Englert, P. A. J.; Caffee, M. W.; Vincent, J.; Castaneda, C.; Reedy, R. C.
1997-01-01
Radionuclides produced in lunar rocks by cosmic ray interactions are measured using Accelerator Mass Spectrometry or gamma-ray spectroscopy. From these measurements, estimates of the solar proton flux over time periods characterized by the half-life of the isotope under study can be made, if all the cross sections for all the reactions of all cosmic ray particles with all elements found in lunar rocks are known. Proton production cross sections are very important because (approximately) 98% of solar cosmic rays and (approximately) 87% of galactic cosmic rays are protons in the lunar environment. Many of the needed cross sections have never been measured. Targets of C, Al, Si, SiO2, mg, K, Ca, Fe and Ni have been irradiated using three accelerators to cover a proton energy range of 25-500 MeV. Excitation functions for Be-7, Be-10, Na-22, and Al-26 production from Mg and Al will be reported, and the consequences of using these new cross section values to estimate solar proton fluxes discussed.
NASA Astrophysics Data System (ADS)
Ullmann, J. L.; Kawano, T.; Bredeweg, T. A.; Couture, A.; Haight, R. C.; Jandel, M.; O'Donnell, J. M.; Rundberg, R. S.; Vieira, D. J.; Wilhelmy, J. B.; Becker, J. A.; Chyzh, A.; Wu, C. Y.; Baramsai, B.; Mitchell, G. E.; Krtička, M.
2014-03-01
Background: Accurate knowledge of the U238(n,γ) cross section is important for developing theoretical nuclear reaction models and for applications. However, capture cross sections are difficult to calculate accurately and often must be measured. Purpose: We seek to confirm previous measurements and test cross-section calculations with an emphasis on the unresolved resonance region from 1 to 500 keV. Method: Cross sections were measured from 10 eV to 500 keV using the DANCE detector array at the LANSCE spallation neutron source. The measurements used a thin target, 48 mg/cm2 of depleted uranium. Gamma cascade spectra were also measured to provide an additional constraint on calculations. The data are compared to cross-section calculations using the code CoH3 and cascade spectra calculations made using the code dicebox. Results: This new cross-section measurement confirms the previous data. The measured gamma-ray spectra suggest the need for additional low-lying dipole strength in the radiative strength function. New Hauser-Feshbach calculations including this strength accurately predict the capture cross section without renormalization. Conclusions: The present cross-section data confirm previous measurements. Including additional low-lying dipole strength in the radiative strength function may lead to more accurate cross-section calculations in nuclei where <Γγ> has not been measured.
Data Evaluation of Actinide Cross Sections: 238Pu, 237Pu, and 236Pu
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guaglioni, S.; Jurgenson, E.; Descalle, M. A.
This report documents the recent evaluation of the 236Pu, 237Pu, and 238Pu cross section sets. Nuclear data evaluation is the fundamental interface that takes measured nuclear cross section data and turns them into a continuous curve that 1) is consistent with other measurements and nuclear reaction theory/models, and 2) is required by down-stream users. All experiments that generate nuclear data need to include an evaluation step for their data to be broadly useful to the end users.
Review of Nuclear Physics Experiments for Space Radiation
NASA Technical Reports Server (NTRS)
Norbury, John W.; Miller, Jack; Adamczyk, Anne M.; Heilbronn, Lawrence H.; Townsend, Lawrence W.; Blattnig, Steve R.; Norman, Ryan B.; Guetersloh, Stephen B.; Zeitlin, Cary J.
2011-01-01
Human space flight requires protecting astronauts from the harmful effects of space radiation. The availability of measured nuclear cross section data needed for these studies is reviewed in the present paper. The energy range of interest for radiation protection is approximately 100 MeV/n to 10 GeV/n. The majority of data are for projectile fragmentation partial and total cross sections, including both charge changing and isotopic cross sections. The cross section data are organized into categories which include charge changing, elemental, isotopic for total, single and double differential with respect to momentum, energy and angle. Gaps in the data relevant to space radiation protection are discussed and recommendations for future experiments are made.
A new compilation of experimental nuclear data for total reaction cross sections
NASA Astrophysics Data System (ADS)
Lantz, Mattias; Sihver, L.
The nucleon-nucleus and nucleus-nucleus total reaction cross sections are of importance in many different fields, both for a better theoretical understanding as well as for a number of applications, including space radiation dosimetry. We have performed a comprehensive literature study in order to find all available experimental data on total reaction cross sections, σR , and interaction cross sections, σI , for neutrons, protons, and all stable and exotic heavy ions. Excluded from the data base are measurements where the cross sections have been derived through model-dependent calculations from other kinds of measurements. The objective of the study is to identify where more measurements are needed in view of different applications, and to make the data easily available for model developers and experimentalists. We will present some examples from the study, which is in the stage of quality control of all the gathered data.
Electron-impact Multiple-ionization Cross Sections for Atoms and Ions of Helium through Zinc
NASA Astrophysics Data System (ADS)
Hahn, M.; Müller, A.; Savin, D. W.
2017-12-01
We compiled a set of electron-impact multiple-ionization (EIMI) cross section for astrophysically relevant ions. EIMIs can have a significant effect on the ionization balance of non-equilibrium plasmas. For example, it can be important if there is a rapid change in the electron temperature or if there is a non-thermal electron energy distribution, such as a kappa distribution. Cross section for EIMI are needed in order to account for these processes in plasma modeling and for spectroscopic interpretation. Here, we describe our comparison of proposed semiempirical formulae to available experimental EIMI cross-section data. Based on this comparison, we interpolated and extrapolated fitting parameters to systems that have not yet been measured. A tabulation of the fit parameters is provided for 3466 EIMI cross sections and the associated Maxwellian plasma rate coefficients. We also highlight some outstanding issues that remain to be resolved.
SASS-1--SUBASSEMBLY STRESS SURVEY CODE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Friedrich, C.M.
1960-01-01
SASS-1, an IBM-704 FORTRAN code, calculates pressure, thermal, and combined stresses in a nuclear reactor core subassembly. In addition to cross- section stresses, the code calculates axial shear stresses needed to keep plane cross sections plane under axial variations of temperature. The input and output nomenclature, arrangement, and formats are described. (B.O.G.)
Raman backscatter measurement research on water vapor systems
NASA Technical Reports Server (NTRS)
Workman, G. L.
1975-01-01
Raman backscatter techniques proved to be a useful remote sensing tool, whose full potential has not been realized. The types of information available from laser probes in atmospheric studies are reviewed. Detection levels for known Raman cross sections are calculated using the laser radar equation. Laboratory experiments performed for H2O, N2, SO2, O2 and HCL indicate that accurate wavelength cross sections need to be obtained, as well as more emphasis on obtaining accurate Raman cross sections of molecular species at wavelengths in the ultraviolet spectra.
Midgley, S M
2004-01-21
A novel parameterization of x-ray interaction cross-sections is developed, and employed to describe the x-ray linear attenuation coefficient and mass energy absorption coefficient for both elements and mixtures. The new parameterization scheme addresses the Z-dependence of elemental cross-sections (per electron) using a simple function of atomic number, Z. This obviates the need for a complicated mathematical formalism. Energy dependent coefficients describe the Z-direction curvature of the cross-sections. The composition dependent quantities are the electron density and statistical moments describing the elemental distribution. We show that it is possible to describe elemental cross-sections for the entire periodic table and at energies above the K-edge (from 6 keV to 125 MeV), with an accuracy of better than 2% using a parameterization containing not more than five coefficients. For the biologically important elements 1 < or = Z < or = 20, and the energy range 30-150 keV, the parameterization utilizes four coefficients. At higher energies, the parameterization uses fewer coefficients with only two coefficients needed at megavoltage energies.
NASA Technical Reports Server (NTRS)
Scruggs, T.; Moraguez, M.; Patankar, K.; Fitz-Coy, N.; Liou, J.-C.; Sorge, M.; Huynh, T.
2016-01-01
Debris fragments from the hypervelocity impact testing of DebriSat are being collected and characterized for use in updating existing satellite breakup models. One of the key parameters utilized in these models is the ballistic coefficient of the fragment which is directly related to its area-to-mass ratio. However, since the attitude of fragments varies during their orbital lifetime, it is customary to use the average cross-sectional area in the calculation of the area-to-mass ratio. The average cross-sectional area is defined as the average of the projected surface areas perpendicular to the direction of motion and has been shown to be equal to one-fourth of the total surface area of a convex object. Unfortunately, numerous fragments obtained from the DebriSat experiment show significant concavity (i.e., shadowing) and thus we have explored alternate methods for computing the average cross-sectional area of the fragments. An imaging system based on the volumetric reconstruction of a 3D object from multiple 2D photographs of the object was developed for use in determining the size characteristic (i.e., characteristics length) of the DebriSat fragments. For each fragment, the imaging system generates N number of images from varied azimuth and elevation angles and processes them using a space-carving algorithm to construct a 3D point cloud of the fragment. This paper describes two approaches for calculating the average cross-sectional area of debris fragments based on the 3D imager. Approach A utilizes the constructed 3D object to generate equally distributed cross-sectional area projections and then averages them to determine the average cross-sectional area. Approach B utilizes a weighted average of the area of the 2D photographs to directly compute the average cross-sectional area. A comparison of the accuracy and computational needs of each approach is described as well as preliminary results of an analysis to determine the "optimal" number of images needed for the 3D imager to accurately measure the average cross sectional area of objects with known dimensions.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greebler, P.; Goldman, E.
1962-12-19
Doppler calculations for large fast ceramic reactors (FCR), using recent cross section information and improved methods, are described. Cross sections of U/sup 238/, Pu/sup 239/, and Pu/sup 210/ with fuel temperature variations needed for perturbation calculations of Doppler reactivity changes are tabulated as a function of potential scattering cross section per absorber isotope at energies below 400 kev. These may be used in Doppler calculations for anv fast reactor. Results of Doppler calculations on a large fast ceramic reactor are given to show the effects of the improved calculation methods and of recent cross secrion data on the calculated Dopplermore » coefficient. The updated methods and cross sections used yield a somewhat harder spectrum and accordingly a somewhat smaller Doppler coefficient for a given FCR core size and composition than calculated in earlier work, but they support the essential conclusion derived earlier that the Doppler effect provides an important safety advantage in a large FCR. 28 references. (auth)« less
Influence of strut cross-section of stents on local hemodynamics in stented arteries
NASA Astrophysics Data System (ADS)
Jiang, Yongfei; Zhang, Jun; Zhao, Wanhua
2016-05-01
Stenting is a very effective treatment for stenotic vascular diseases, but vascular geometries altered by stent implantation may lead to flow disturbances which play an important role in the initiation and progression of restenosis, especially in the near wall in stented arterial regions. So stent designs have become one of the indispensable factors needed to be considered for reducing the flow disturbances. In this paper, the structural designs of strut cross-section are considered as an aspect of stent designs to be studied in details. Six virtual stents with different strut cross-section are designed for deployments in the same ideal arterial model. Computational fluid dynamics (CFD) methods are performed to study how the shape and the aspect ratio (AR) of strut cross-section modified the local hemodynamics in the stented segments. The results indicate that stents with different strut cross-sections have different influence on the hemodynamics. Stents with streamlined cross-sectional struts for circular arc or elliptical arc can significantly enhance wall shear stress (WSS) in the stented segments, and reduce the flow disturbances around stent struts. The performances of stents with streamlined cross-sectional struts are better than that of stents with non-streamlined cross-sectional struts for rectangle. The results also show that stents with a larger AR cross-section are more conductive to improve the blood flow. The present study provides an understanding of the flow physics in the vicinity of stent struts and indicates that the shape and AR of strut cross-section ought to be considered as important factors to minimize flow disturbance in stent designs.
Ivanova, Iva; Salmon, David P; Gollan, Tamar H
2014-05-01
In this study, we investigated dual-language decline in non-balanced bilinguals with probable Alzheimer's disease (AD) both longitudinally and cross-sectionally. We examined patients' naming accuracy on the Boston Naming Test (BNT: Kaplan et al., 1983) over three testing sessions (longitudinal analysis) and compared their performance to that of matched controls (cross-sectional analysis). We found different longitudinal and cross-sectional patterns of decline: Longitudinally, the non-dominant language seemed to decline more steeply than the dominant language, but, cross-sectionally, differences between patients and controls were larger for the dominant than for the non-dominant language, especially at the initial testing session. This differential pattern of results for cross-sectional versus longitudinal decline was supported by correlations between decline measures and BNT item characteristics. Further studies will be needed to better characterize the nature of linguistic decline in bilinguals with AD; however, these results suggest that representational robustness of individual lexical representations, rather than language membership, might determine the time course of decline for naming in bilinguals with AD.
Study of the Bistatic Radar Cross Section of a 155-mm Artillery Round
2017-06-01
study . Section 3 compares the accuracy of the 2 EM modeling software packages used in this work. In Section 4, we discuss the relevant Approved for...ARL-TR-8045 ● JUNE 2017 US Army Research Laboratory Study of the Bistatic Radar Cross Section of a 155-mm Artillery Round by...when it is no longer needed. Do not return it to the originator. ARL-TR-8045 ● JUNE 2017 US Army Research Laboratory Study of the
Awareness about Autism among School Teachers in Oman: A Cross-Sectional Study
ERIC Educational Resources Information Center
Al-Sharbati, Marwan M.; Al-Farsi, Yahya M.; Ouhtit, Allal; Waly, Mostafa I.; Al-Shafaee, Mohamed; Al-Farsi, Omar; Al-Khaduri, Maha; Al-Said, Mona F.; Al-Adawi, Samir
2015-01-01
Children with special needs such as those with autism spectrum disorder have been recorded as ostracized and stigmatized in many parts of the world. Little is known about whether such negative views are present among mainstream teachers in Oman. A cross-sectional study was conducted to evaluate school teachers' awareness about autism spectrum…
Measuring Two Key Parameters of H3 Color Centers in Diamond
NASA Technical Reports Server (NTRS)
Roberts, W. Thomas
2005-01-01
A method of measuring two key parameters of H3 color centers in diamond has been created as part of a continuing effort to develop tunable, continuous-wave, visible lasers that would utilize diamond as the lasing medium. (An H3 color center in a diamond crystal lattice comprises two nitrogen atoms substituted for two carbon atoms bonded to a third carbon atom. H3 color centers can be induced artificially; they also occur naturally. If present in sufficient density, they impart a yellow hue.) The method may also be applicable to the corresponding parameters of other candidate lasing media. One of the parameters is the number density of color centers, which is needed for designing an efficient laser. The other parameter is an optical-absorption cross section, which, as explained below, is needed for determining the number density. The present method represents an improvement over prior methods in which optical-absorption measurements have been used to determine absorption cross sections or number densities. Heretofore, in order to determine a number density from such measurements, it has been necessary to know the applicable absorption cross section; alternatively, to determine the absorption cross section from such measurements, it has been necessary to know the number density. If, as in this case, both the number density and the absorption cross section are initially unknown, then it is impossible to determine either parameter in the absence of additional information.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koehler, Paul E.
2014-03-05
There are many (n,γ) cross sections of great interest to radiochemical diagnostics and to nuclear astrophysics which are beyond the reach of current measurement techniques, and likely to remain so for the foreseeable future. In contrast, total neutron cross sections currently are feasible for many of these nuclides and provide almost all the information needed to accurately calculate the (n,γ) cross sections via the nuclear statistical model (NSM). I demonstrate this for the case of 151Sm; NSM calculations constrained using average resonance parameters obtained from total cross section measurements made in 1975, are in excellent agreement with recent 151Sm (n,γ)more » measurements across a wide range of energy. Furthermore, I demonstrate through simulations that total cross section measurements can be made at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center for samples as small as 10μg. Samples of this size should be attainable for many nuclides of interest. Finally, I estimate that over half of the radionuclides identified ~20 years ago as having (n,γ) cross sections of importance to s-process nucleosynthesis studies (24/43) and radiochemical diagnostics (11/19), almost none of which have been measured, can be constrained using this technique.« less
Molecular processes in a high temperature shock layer
NASA Technical Reports Server (NTRS)
Guberman, S. L.
1985-01-01
The development of techniques for the calculation of electron capture widths, electronic wave functions, cross sections and rates needed for the description of the dissociative recombination (DR) of molecular ions with electrons were described. The cross sections and rates were calculated by using harmonic oscillator wave functions for the ion and a delta function approximation for the continuum vibrational wave function in the repulsive dissociative channel. In order to obtain DR cross sections of quantitative accuracy, a computer program which solves the one dimensional nuclear motion wave equation was revised to calculate the cross sections and rates. The program and the new results are described. Included is a discussion of large windows found in the dissociative recombination cross sections from excited ion vibrational levels. These windows have not been previously reported in the literature. The magnitude of the DR cross sections for several dissociative routes are sensitive to the location of the crossing of the neutral and ion potential curves. Studies of the effects of basis set and CI wave function size on vertical excitation energies are described. Preliminary studies on N2 and O2 using large scale wave functions are also reported.
Thick-target transmission method for excitation functions of interaction cross sections
NASA Astrophysics Data System (ADS)
Aikawa, M.; Ebata, S.; Imai, S.
2016-09-01
We propose a method, called as thick-target transmission (T3) method, to obtain an excitation function of interaction cross sections. In an ordinal experiment to measure the excitation function of interaction cross sections by the transmission method, we need to change the beam energy for each cross section. In the T3 method, the excitation function is derived from the beam attenuations measured at the targets of different thicknesses without changing the beam energy. The advantage of the T3 method is the simplicity and availability for radioactive beams. To confirm the availability, we perform a simulation for the 12C + 27Al system with the PHITS code instead of actual experiments. Our results have large uncertainties but well reproduce the tendency of the experimental data.
Accurate universal parameterization of absorption cross sections III--light systems
NASA Technical Reports Server (NTRS)
Tripathi, R. K.; Cucinotta, F. A.; Wilson, J. W.
1999-01-01
Our prior nuclear absorption cross sections model [R.K. Tripathi, F.A. Cucinotta, J.W. Wilson, Nucl. Instr. and Meth. B 117 (1996) 347; R.K. Tripathi, J.W. Wilson, F.A. Cucinotta, Nucl. Instr. and Meth. B 129 (1997) 11] is extended for light systems (A < or = 4) where either both projectile and target are light particles or one is light particle and the other is medium or heavy nucleus. The agreement with experiment is excellent for these cases as well. Present work in combination with our original model provides a comprehensive picture of absorption cross sections for light, medium and heavy systems. As a result the extended model can reliably be used in all studies where there is a need for absorption cross sections.
A program to measure new energetic particle nuclear interaction cross sections
NASA Astrophysics Data System (ADS)
Guzik, T. G.; Albergo, S.; Chen, C.-X.; Costa, S.; Crawford, H. J.; Engelage, J.; Ferrando, P.; Flores, I.; Greiner, L.; Jones, F. C.; Knott, C. N.; Ko, S.; Lindstrom, P. J.; Mazotta, J.; Mitchell, J. W.; Romanski, J.; Potenza, R.; Soutoul, A.; Testard, O.; Tull, C. E.; Tuve, C.; Waddington, C. J.; Webber, W. R.; Wefel, J. P.; Zhang, X.
1994-10-01
The Transport Collaboration, consisting of researchers from institutions in France, Germany, Italy, and the USA, has established a program to make new measurements of nuclear interaction cross sections for heavy projectiles (Z greater than or equal to 2) in targets of liquid H2, He and heavier materials. Such cross sections directly affect calculations of galactic and solar cosmic ray transport through matter and are needed for accurate radiation hazard assessment. To date, the collaboration has obtained data using the Lawrence Berkeley Laboratory Bevalac HISS facility with 20 projectiles from He-4 to Ni-58 in the energy range 393-910 MeV/nucleon. Preliminary results from the analysis of these data are presented here and compared to other measurements and to cross section prediction formulae.
A program to measure new energetic particle nuclear interaction cross sections
NASA Technical Reports Server (NTRS)
Guzik, T. G.; Albergo, S.; Chen, C. X.; Costa, S.; Crawford, H. J.; Engelage, J.; Ferrando, P.; Flores, I.; Greiner, L.; Jones, F. C.
1994-01-01
The Transport Collaboration, consisting of researchers from institutions in France, Germany, Italy, and the USA, has established a program to make new measurements of nuclear interaction cross sections for heavy projectiles (Z greater than or equal to 2) in targets of liquid H2, He and heavier materials. Such cross sections directly affect calculations of galactic and solar cosmic ray transport through matter and are needed for accurate radiation hazard assessment. To date, the collaboration has obtained data using the Lawrence Berkeley Laboratory Bevalac HISS facility with 20 projectiles from He-4 to Ni-58 in the energy range 393-910 MeV/nucleon. Preliminary results from the analysis of these data are presented here and compared to other measurements and to cross section prediction formulae.
Ultraviolet absorption cross-sections of hot carbon dioxide
NASA Astrophysics Data System (ADS)
Oehlschlaeger, Matthew A.; Davidson, David F.; Jeffries, Jay B.; Hanson, Ronald K.
2004-12-01
The temperature-dependent ultraviolet absorption cross-section for CO 2 has been measured in shock-heated gases between 1500 and 4500 K at 216.5, 244, 266, and 306 nm. Continuous-wave lasers provide the spectral brightness to enable precise time-resolved measurements with the microsecond time-response needed to monitor thermal decomposition of CO 2 at temperatures above 3000 K. The photophysics of the highly temperature dependent cross-section is discussed. The new data allows the extension of CO 2 absorption-based temperature sensing methods to higher temperatures, such as those found in behind detonation waves.
Simple, empirical approach to predict neutron capture cross sections from nuclear masses
NASA Astrophysics Data System (ADS)
Couture, A.; Casten, R. F.; Cakirli, R. B.
2017-12-01
Background: Neutron capture cross sections are essential to understanding the astrophysical s and r processes, the modeling of nuclear reactor design and performance, and for a wide variety of nuclear forensics applications. Often, cross sections are needed for nuclei where experimental measurements are difficult. Enormous effort, over many decades, has gone into attempting to develop sophisticated statistical reaction models to predict these cross sections. Such work has met with some success but is often unable to reproduce measured cross sections to better than 40 % , and has limited predictive power, with predictions from different models rapidly differing by an order of magnitude a few nucleons from the last measurement. Purpose: To develop a new approach to predicting neutron capture cross sections over broad ranges of nuclei that accounts for their values where known and which has reliable predictive power with small uncertainties for many nuclei where they are unknown. Methods: Experimental neutron capture cross sections were compared to empirical mass observables in regions of similar structure. Results: We present an extremely simple method, based solely on empirical mass observables, that correlates neutron capture cross sections in the critical energy range from a few keV to a couple hundred keV. We show that regional cross sections are compactly correlated in medium and heavy mass nuclei with the two-neutron separation energy. These correlations are easily amenable to predict unknown cross sections, often converting the usual extrapolations to more reliable interpolations. It almost always reproduces existing data to within 25 % and estimated uncertainties are below about 40 % up to 10 nucleons beyond known data. Conclusions: Neutron capture cross sections display a surprisingly strong connection to the two-neutron separation energy, a nuclear structure property. The simple, empirical correlations uncovered provide model-independent predictions of neutron capture cross sections, extending far from stability, including for nuclei of the highest sensitivity to r -process nucleosynthesis.
Rayleigh scattering cross-section measurements of nitrogen, argon, oxygen and air
NASA Astrophysics Data System (ADS)
Thalman, Ryan; Zarzana, Kyle J.; Tolbert, Margaret A.; Volkamer, Rainer
2014-11-01
Knowledge about Rayleigh scattering cross sections is relevant to predictions about radiative transfer in the atmosphere, and needed to calibrate the reflectivity of mirrors that are used in high-finesse optical cavities to measure atmospheric trace gases and aerosols. In this work we have measured the absolute Rayleigh scattering cross-section of nitrogen at 405.8 and 532.2 nm using cavity ring-down spectroscopy (CRDS). Further, multi-spectral measurements of the scattering cross-sections of argon, oxygen and air are presented relative to that of nitrogen from 350 to 660 nm using Broadband Cavity Enhanced Spectroscopy (BBCES). The reported measurements agree with refractive index based theory within 0.2±0.4%, and have an absolute accuracy of better than 1.3%. Our measurements expand the spectral range over which Rayleigh scattering cross section measurements of argon, oxygen and air are available at near-ultraviolet wavelengths. The expressions used to represent the Rayleigh scattering cross-section in the literature are evaluated to assess how uncertainties affect quantities measured by cavity enhanced absorption spectroscopic (CEAS) techniques. We conclude that Rayleigh scattering cross sections calculated from theory provide accurate data within very low error bounds, and are suited well to calibrate CEAS measurements of atmospheric trace gases and aerosols.
Reducing Uncertainties in Neutron-Induced Fission Cross Sections Using a Time Projection Chamber
NASA Astrophysics Data System (ADS)
Manning, Brett; Niffte Collaboration
2015-10-01
Neutron-induced fission cross sections for actinides have long been of great interest for nuclear energy and stockpile stewardship. Traditionally, measurements were performed using fission chambers which provided limited information about the detected fission events. For the case of 239Pu(n,f), sensitivity studies have shown a need for more precise measurements. Recently the Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) has developed the fission Time Projection Chamber (fissionTPC) to measure fission cross sections to better than 1% uncertainty by providing 3D tracking of fission fragments. The fissionTPC collected data to calculate the 239Pu(n,f) cross section at the Weapons Neutron Research facility at the Los Alamos Neutron Science Center during the 2014 run cycle. Preliminary analysis has been focused on studying particle identification and target and beam non-uniformities to reduce the uncertainty on the cross section. Additionally, the collaboration is investigating other systematic errors that could not be well studied with a traditional fission chamber. LA-UR-15-24906.
Electron Impact Multiple Ionization Cross Sections for Solar Physics
NASA Astrophysics Data System (ADS)
Hahn, M.; Savin, D. W.; Mueller, A.
2017-12-01
We have compiled a set of electron-impact multiple ionization (EIMI) cross sections for astrophysically relevant ions. EIMI can have a significant effect on the ionization balance of non-equilibrium plasmas. For example, it can be important if there is a rapid change in the electron temperature, as in solar flares or in nanoflare coronal heating. EIMI is also likely to be significant when the electron energy distribution is non-thermal, such as if the electrons follow a kappa distribution. Cross sections for EIMI are needed in order to account for these processes in plasma modeling and for spectroscopic interpretation. Here, we describe our comparison of proposed semiempirical formulae to the available experimental EIMI cross section data. Based on this comparison, we have interpolated and extrapolated fitting parameters to systems that have not yet been measured. A tabulation of the fit parameters is provided for thousands of EIMI cross sections. We also highlight some outstanding issues that remain to be resolved.
Reference Cross Sections for Charged-particle Monitor Reactions
NASA Astrophysics Data System (ADS)
Hermanne, A.; Ignatyuk, A. V.; Capote, R.; Carlson, B. V.; Engle, J. W.; Kellett, M. A.; Kibédi, T.; Kim, G.; Kondev, F. G.; Hussain, M.; Lebeda, O.; Luca, A.; Nagai, Y.; Naik, H.; Nichols, A. L.; Nortier, F. M.; Suryanarayana, S. V.; Takács, S.; Tárkányi, F. T.; Verpelli, M.
2018-02-01
Evaluated cross sections of beam-monitor reactions are expected to become the de-facto standard for cross-section measurements that are performed over a very broad energy range in accelerators in order to produce particular radionuclides for industrial and medical applications. The requirements for such data need to be addressed in a timely manner, and therefore an IAEA coordinated research project was launched in December 2012 to establish or improve the nuclear data required to characterise charged-particle monitor reactions. An international team was assembled to recommend more accurate cross-section data over a wide range of targets and projectiles, undertaken in conjunction with a limited number of measurements and more extensive evaluations of the decay data of specific radionuclides. Least-square evaluations of monitor-reaction cross sections including uncertainty quantification have been undertaken for charged-particle beams of protons, deuterons, 3He- and 4He-particles. Recommended beam monitor reaction data with their uncertainties are available at the IAEA-NDS medical portal http://www-nds.iaea.org/medical/monitor_reactions.html.
Watts, Kristen; Lagalante, Anthony
2018-06-06
Art conservation science is in need of a relatively nondestructive way of rapidly identifying the binding media within a painting cross-section and isolating binding media to specific layers within the cross-section. Knowledge of the stratigraphy of cross-sections can be helpful for removing possible unoriginal paint layers on the artistic work. Desorption electrospray ionization-mass spectrometry (DESI-MS) was used in ambient mode to study cross-sections from mock-up layered paint samples and samples from a 17th century baroque painting. The DESI spray was raster scanned perpendicular to the cross-section layers to maximize lateral resolution then analyzed with a triple quadrupole mass analyzer in linear ion trap mode. From these scans, isobaric mass maps were created to map the locations of masses indicative of particular binding media onto the cross-sections. Line paint-outs of pigments in different binding media showed specific and unique ions to distinguish between the modern acrylic media and the lipid containing binding media. This included: OP (EO) 9 surfactant in positive ESI for acrylic (m/z 621), and oleic (m/z 281), stearic (m/z 283), and azelaic (m/z 187) acids in negative ESI for oil and egg tempera. DESI-MS maps of mock-up cross-sections of layered pigmented binding media showed correlation between these ions and the layers with a spatial resolution of 100 μm. DESI-MS is effective in monitoring binding media within an intact painting cross-section via mass spectrometric methods. This includes distinguishing between lipid-containing and modern binding materials present in a known mockup cross section matrix as well as identifying lipid binding media in a 17th century baroque era painting. This article is protected by copyright. All rights reserved.
USDA-ARS?s Scientific Manuscript database
Accurate, nonintrusive, and inexpensive techniques are needed to measure energy expenditure (EE) in free-living populations. Our primary aim in this study was to validate cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on observable participant cha...
NASA Technical Reports Server (NTRS)
Parkinson, W. H.; Yoshino, K.
1997-01-01
An account is given of progress during the period 8/l/96-7/31/97 on work on (a) cross section measurements of O2 S-R using a Fourier transform spectrometer (FTS) at the Photon Factory in Japan; (b) the determination of the predissociation linewidths of the Schumann-Runge bands (S-R) of 02; (c) cross section measurements of 02 Herzberg bands using a Fourier transform spectrometer (FTS) at Imperial College; and (d) cross section measurements of H2O in the wavelength region 120-188 nm. The experimental investigations are effected at high resolution with a 6.65 m scanning spectrometer and with the Fourier transform spectrometer. Below 175 nm, synchrotron radiation is most suitable for cross section measurements in combination with spectrometers at the Photon Factory Japan. Cross section measurements of the Doppler limited bands depend on using the very high resolution, available with the Fourier transform spectrometer, (0.025/cm resolution). All of these spectroscopic measurements are needed for accurate calculations of the production of atomic oxygen, the penetration of solar radiation into the Earth's atmosphere, and photochemistry of minor molecules.
NASA Astrophysics Data System (ADS)
Dunn, Michael
2008-10-01
For over 30 years, the Oak Ridge National Laboratory (ORNL) has performed research and development to provide more accurate nuclear cross-section data in the resonance region. The ORNL Nuclear Data (ND) Program consists of four complementary areas of research: (1) cross-section measurements at the Oak Ridge Electron Linear Accelerator; (2) resonance analysis methods development with the SAMMY R-matrix analysis software; (3) cross-section evaluation development; and (4) cross-section processing methods development with the AMPX software system. The ND Program is tightly coupled with nuclear fuel cycle analyses and radiation transport methods development efforts at ORNL. Thus, nuclear data work is performed in concert with nuclear science and technology needs and requirements. Recent advances in each component of the ORNL ND Program have led to improvements in resonance region measurements, R-matrix analyses, cross-section evaluations, and processing capabilities that directly support radiation transport research and development. Of particular importance are the improvements in cross-section covariance data evaluation and processing capabilities. The benefit of these advances to nuclear science and technology research and development will be discussed during the symposium on Nuclear Physics Research Connections to Nuclear Energy.
Neutron-induced fission cross section of 242Pu from 15 MeV to 20 MeV
NASA Astrophysics Data System (ADS)
Jovančević, N.; Salvador-Castineira, P.; Daraban, L.; Vidali, M.; Heyse, J.; Oberstedt, S.; Hambsch, F.-J.; Bonaldi, C.; Geerts, W.
2017-09-01
Accurate nuclear-data needs in the fast-neutron-energy region have been recently addressed for the development of next generation nuclear power plants (GEN-IV) by the OECD Nuclear Energy Agency (NEA). This sensitivity study has shown that of particular interest is the 242Pu(n,f) cross section for fast reactor systems. Measurements have been performed with quasi-monoenergetic neutrons in the energy range from 15 MeV to 20 MeV produced by the Van de Graaff accelerator of the JRC-Geel. A twin Frisch-grid ionization chamber has been used in a back-to-back configuration as fission fragment detector. The 242Pu(n,f) cross section has been normalized to 238U(n,f) cross section data. The results were compared with existing literature data and show acceptable agreement within 5%.
Development of ORIGEN Libraries for Mixed Oxide (MOX) Fuel Assembly Designs
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mertyurek, Ugur; Gauld, Ian C.
In this research, ORIGEN cross section libraries for reactor-grade mixed oxide (MOX) fuel assembly designs have been developed to provide fast and accurate depletion calculations to predict nuclide inventories, radiation sources and thermal decay heat information needed in safety evaluations and safeguards verification measurements of spent nuclear fuel. These ORIGEN libraries are generated using two-dimensional lattice physics assembly models that include enrichment zoning and cross section data based on ENDF/B-VII.0 evaluations. Using the SCALE depletion sequence, burnup-dependent cross sections are created for selected commercial reactor assembly designs and a representative range of reactor operating conditions, fuel enrichments, and fuel burnup.more » The burnup dependent cross sections are then interpolated to provide problem-dependent cross sections for ORIGEN, avoiding the need for time-consuming lattice physics calculations. The ORIGEN libraries for MOX assembly designs are validated against destructive radiochemical assay measurements of MOX fuel from the MALIBU international experimental program. This program included measurements of MOX fuel from a 15 × 15 pressurized water reactor assembly and a 9 × 9 boiling water reactor assembly. The ORIGEN MOX libraries are also compared against detailed assembly calculations from the Phase IV-B numerical MOX fuel burnup credit benchmark coordinated by the Nuclear Energy Agency within the Organization for Economic Cooperation and Development. Finally, the nuclide compositions calculated by ORIGEN using the MOX libraries are shown to be in good agreement with other physics codes and with experimental data.« less
Development of ORIGEN Libraries for Mixed Oxide (MOX) Fuel Assembly Designs
Mertyurek, Ugur; Gauld, Ian C.
2015-12-24
In this research, ORIGEN cross section libraries for reactor-grade mixed oxide (MOX) fuel assembly designs have been developed to provide fast and accurate depletion calculations to predict nuclide inventories, radiation sources and thermal decay heat information needed in safety evaluations and safeguards verification measurements of spent nuclear fuel. These ORIGEN libraries are generated using two-dimensional lattice physics assembly models that include enrichment zoning and cross section data based on ENDF/B-VII.0 evaluations. Using the SCALE depletion sequence, burnup-dependent cross sections are created for selected commercial reactor assembly designs and a representative range of reactor operating conditions, fuel enrichments, and fuel burnup.more » The burnup dependent cross sections are then interpolated to provide problem-dependent cross sections for ORIGEN, avoiding the need for time-consuming lattice physics calculations. The ORIGEN libraries for MOX assembly designs are validated against destructive radiochemical assay measurements of MOX fuel from the MALIBU international experimental program. This program included measurements of MOX fuel from a 15 × 15 pressurized water reactor assembly and a 9 × 9 boiling water reactor assembly. The ORIGEN MOX libraries are also compared against detailed assembly calculations from the Phase IV-B numerical MOX fuel burnup credit benchmark coordinated by the Nuclear Energy Agency within the Organization for Economic Cooperation and Development. Finally, the nuclide compositions calculated by ORIGEN using the MOX libraries are shown to be in good agreement with other physics codes and with experimental data.« less
Bartholomew, Kimberley J; Ntoumanis, Nikos; Ryan, Richard M; Bosch, Jos A; Thøgersen-Ntoumani, Cecilie
2011-11-01
Drawing from self-determination theory, three studies explored the social-environmental conditions that satisfy versus thwart psychological needs and, in turn, affect psychological functioning and well-being or ill-being. In cross-sectional Studies 1 and 2, structural equation modeling analyses supported latent factor models in which need satisfaction was predicted by athletes' perceptions of autonomy support, and need thwarting was better predicted by coach control. Athletes' perceptions of need satisfaction predicted positive outcomes associated with sport participation (vitality and positive affect), whereas need thwarting more consistently predicted maladaptive outcomes (disordered eating, burnout, depression, negative affect, and physical symptoms). In addition, athletes' perceptions of psychological need thwarting were significantly associated with perturbed physiological arousal (elevated levels of secretory immunoglobulin A) prior to training. The final study involved the completion of a diary and supported the relations observed in the cross-sectional studies at a daily level. These findings have important implications for the operationalization and measurement of interpersonal styles and psychological needs.
Bednarska, Agnieszka J; Wyżga, Bartłomiej; Mikuś, Paweł; Kędzior, Renata
2018-01-01
Effects of passive restoration of mountain rivers on the organisms inhabiting exposed riverine sediments are considerably less understood than those concerning aquatic biota. Thus, the effects of a recovery of the Raba River after abandonment of maintenance of its channelization scheme on ground beetle (Coleoptera: Carabidae) communities were investigated by comparing 6 unmanaged cross-sections and 6 cross-sections from adjacent channelized reaches. In each cross-section, ground beetles were collected from 12 sampling sites in spring, summer, and autumn, and 8 habitat parameters characterizing the cross-sections and sampling sites were determined. Within a few years after abandonment of the Raba River channelization scheme, the width of this gravel-bed river increased up to three times and its multi-thread pattern became re-established. Consequently, unmanaged river cross-sections had significantly larger channel width and more low-flow channels and eroding cutbanks than channelized cross-sections. Moreover, sampling sites in the unmanaged cross-sections were typified by significantly steeper average surface slope and larger average distance from low-flow channels than the sites in channelized cross-sections. In total, 3992 individuals from 78 taxa were collected during the study. The ground beetle assemblages were significantly more abundant and richer in species in the unmanaged than in the channelized cross-sections but no significant differences in carabid diversity indices between the two cross-section types were recorded. Redundancy Analysis indicated active river zone width as the only variable explaining differences in abundance and species richness among the cross-sections. Multiple regression analysis indicated species diversity to predominantly depend on the degree of plant cover and substrate grain size. The study showed that increased availability of exposed sediments in the widened river reaches allowed ground beetles to increase their abundance and species richness within a few years after the onset of river restoration, but more time may be needed for development of more diverse carabid communities. Copyright © 2017 Elsevier B.V. All rights reserved.
Study of activation of metal samples from LDEF-1 and Spacelab-2
NASA Technical Reports Server (NTRS)
Laird, C. E.
1991-01-01
The activation of metal samples and other material orbited onboard the Long Duration Exposure Facility (LDEF) and Spacelab-2 were studied. Measurements of the radioactivities of spacecraft materials were made, and corrections for self-absorption and efficiency were calculated. Activation cross sections for specific metal samples were updated while cross sections for other materials were tabulated from the scientific literature. Activation cross sections for 200 MeV neutrons were experimentally determined. Linear absorption coefficients, half lives, branching ratios and other pertinent technical data needed for LDEF sample analyses were tabulated. The status of the sample counting at low background facilities at national laboratories is reported.
Microwave and video sensor fusion for the shape extraction of 3D space objects
NASA Technical Reports Server (NTRS)
Shaw, Scott W.; Defigueiredo, Rui J. P.; Krishen, Kumar
1987-01-01
A new system for the fusion of optical image data and polarized radar scattering cross-sections is presented. By considering the scattering data in conjunction with image data, the problem of ambiguity can be reduced. Only a small part of the surface needs to be reconstructed from the radar cross-sections; the remaining portion is constrained by the optical image.
NASA Astrophysics Data System (ADS)
Booysen, A. J.; Pistorius, C. W. I.; Malherbe, J. A. G.
1991-06-01
The radar cross section of the leading edge of a conducting wing-shaped structure is reduced by replacing part of the structure with a lossless dielectric material. The structure retains its original external shape, thereby ensuring that the aerodynamic properties are not altered by the structural changes needed to reduce the radar cross section.
ERIC Educational Resources Information Center
Ramirez, Dulce M.
2017-01-01
The increasing use of online pedagogy in higher education has revealed a need to analyze factors contributing to student engagement in online courses. Throughout the past decade, social media has been a growing influence in higher education. This quantitative cross-sectional study examined the attitudes of students and faculty towards computer…
Duan, Qiangling; Xiao, Huahua; Gao, Wei; Gong, Liang; Sun, Jinhua
2016-12-15
An experimental investigation of spontaneous ignition and flame propagation at high-pressure hydrogen release via cylindrical tubes with varying cross-section is presented. Tubes with different transverse cross-sections are considered in the experiments: (1) local contraction, (2) local enlargement, (3) abrupt contraction, and (4) abrupt enlargement. The results show that the presence of the varying cross-section geometries can significantly promote the occurrence of spontaneous ignition. Compared to the tube with constant cross-section, the minimum pressure release needed for spontaneous ignition for the varying cross-sections tubes is considerably lower. Moreover, the initial ignition location is closer to the disk in the presence of varying cross-section geometries in comparison with straight channel. As the flame emerges from the outlet of the tube, the velocity of the flame front in the vicinity of the nozzle increases sharply. Then, a deflagration develops across the mixing zone of hydrogen/air mixture. The maximum deflagration overpressure increases linearly with the release pressure. Subsequently, a hydrogen jet flame is produced and evolves different shapes at different release stages. A fireball is formed after the jet flame spouts in the open air. Later, the fireball develops into a jet flame which shifts upward and continues to burn in the vertical direction. Copyright © 2016 Elsevier B.V. All rights reserved.
Frivold, Gro; Slettebø, Åshild; Heyland, Daren K; Dale, Bjørg
2018-01-01
The aim of this study was to explore family members' satisfaction with care and decision-making during the intensive care units stay and their follow-up needs after the patient's discharge or death. A cross-sectional survey study was conducted. Family members of patients recently treated in an ICU were participating. The questionnaire contented of background variables, the instrument Family Satisfaction in ICU (FS-ICU 24) and questions about follow-up needs. Descriptive and non-parametric statistics and a multiple linear regression were used in the analysis. A total of 123 (47%) relatives returned the questionnaire. Satisfaction with care was higher scored than satisfaction with decision-making. Follow- up needs after the ICU stay was reported by 19 (17%) of the participants. Gender and length of the ICU stay were shown as factors identified to predict follow-up needs.
Validation of Cross Sections with Criticality Experiment and Reaction Rates: the Neptunium Case
NASA Astrophysics Data System (ADS)
Leong, L. S.; Tassan-Got, L.; Audouin, L.; Berthier, B.; Le Naour, C.; Stéphan, C.; Paradela, C.; Tarrío, D.; Duran, I.
2014-04-01
The 237Np neutron-induced fission cross section has been recently measured in a large energy range (from eV to GeV) at the n_TOF facility at CERN. When compared to previous measurements the n_TOF fission cross section appears to be higher by 5-7% beyond the fission threshold. To check the relevance of the n_TOF data, we considered a criticality experiment performed at Los Alamos with a 6 kg sphere of 237Np, surrounded by uranium highly enriched in 235U so as to approach criticality with fast neutrons. The multiplication factor keff of the calculation is in better agreement with the experiment when we replace the ENDF/B-VII.0 evaluation of the 237Np fission cross section by the n_TOF data. We also explored the hypothesis of deficiencies of the inelastic cross section in 235U which has been invoked by some authors to explain the deviation of 750 pcm. The large modification needed to reduce the deviation seems to be incompatible with existing inelastic cross section measurements. Also we show that the νbar of 237Np can hardly be incriminated because of the high accuracy of the existing data. Fission rate ratios or averaged fission cross sections measured in several fast neutron fields seem to give contradictory results on the validation of the 237Np cross section but at least one of the benchmark experiments, where the active deposits have been well calibrated for the number of atoms, favors the n_TOF data set. These outcomes support the hypothesis of a higher fission cross section of 237Np.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koehler, Paul E.; Hayes-Sterbenz, Anna C.; Bredeweg, Todd Allen
Total-cross-section measurements are feasible on a much wider range of radioactive samples than (n,γ) cross-section measurements, and information extracted from the former can be used to set tight constraints on the latter. There are many (n,γ) cross sections of great interest to radiochemical diagnostics, nuclear forensics, and nuclear astrophysics which are beyond the reach of current direct measurement, that could be obtained in this way. Our simulations indicate that measurements can be made at the Manuel Lujan Jr. Neutron Scattering Center at the Los Alamos Neutron Science Center for samples as small as 10μg. There are at least 40 high-interestmore » nuclides which should be measurable, including 88Y, 167,168,170,171Tm, 173,174Lu, and 189,190,192Ir.« less
Theoretical and Experimental K+ + Nucleus Total and Reaction Cross Sections from the KDP-RIA Model
NASA Astrophysics Data System (ADS)
Kerr, L. K.; Clark, B. C.; Hama, S.; Ray, L.; Hoffmann, G. W.
2000-02-01
The 5-dimensional spin-0 form of the Kemmer-Duffin-Petiau (KDP) equation is used to calculate scattering observables [elastic differential cross sections (dσ / dΩ), total cross sections (σ Tot ), and total reaction cross sections (σ Reac )] and to deduce σ Tot and σReac from transmission data for K+ + 6Li, 12C, 28Si and 40Ca at several momenta in the range 488 - 714 MeV / c. Realistic uncertainties are generated for the theoretical predictions. These errors, mainly due to uncertainties associated with the elementary K+ + nucleon amplitudes, are large, which may account for some of the disagreement between experimental and theoretical σTot and σReac. The results suggest that the K+ + nucleon amplitudes need to be much better determined before further improvement in the understanding of these data can occur.
Experimental and evaluated photoneutron cross sections for 197Au
NASA Astrophysics Data System (ADS)
Varlamov, V.; Ishkhanov, B.; Orlin, V.
2017-10-01
There is a serious well-known problem of noticeable disagreements between the partial photoneutron cross sections obtained in various experiments. Such data were mainly determined using quasimonoenergetic annihilation photon beams and the method of neutron multiplicity sorting at Lawrence Livermore National Laboratory (USA) and Centre d'Etudes Nucleaires of Saclay (France). The analysis of experimental cross sections employing new objective physical data reliability criteria has shown that many of those are not reliable. The IAEA Coordinated Research Project (CRP) on photonuclear data evaluation was approved. The experimental and previously evaluated cross sections of the partial photoneutron reactions (γ ,1 n ) and (γ ,2 n ) on 197Au were analyzed using the new data reliability criteria. The data evaluated using the new experimental-theoretical method noticeably differ from both experimental data and data previously evaluated using nuclear modeling codes gnash, gunf, alice-f, and others. These discrepancies needed to be resolved.
NASA Technical Reports Server (NTRS)
Orphal, Johannes; Staehelin, Johannes; Tamminen, Johanna; Braathen, Geir; De Backer, Marie-Renee; Bais, Alkiviadis; Balis, Dimitris; Barbe, Alain; Bhartia, Pawan K.; Birk, Manfred;
2016-01-01
The activity Absorption Cross-Sections of Ozone (ACSO) started in 2008 as a joint initiative of the International Ozone Commission (IO3C), the World Meteorological Organization (WMO) and the IGACO (Integrated Global Atmospheric Chemistry Observations) O3/UV subgroup to study, evaluate, and recommend the most suitable ozone absorption cross-section laboratory data to be used in atmospheric ozone measurements. The evaluation was basically restricted to ozone absorption cross-sections in the UV range with particular focus on the Huggins band. Up until now, the data of Bass and Paur published in 1985 (BP, 1985) are still officially recommended for such measurements. During the last decade it became obvious that BP (1985) cross-section data have deficits for use in advanced space-borne ozone measurements. At the same time, it was recognized that the origin of systematic differences in ground-based measurements of ozone required further investigation, in particular whether the BP (1985) cross-section data might contribute to these differences. In ACSO, different sets of laboratory ozone absorption cross-section data (including their dependence on temperature) of the group of Reims (France) (Brion et al., 1993, 1998, 1992, 1995, abbreviated as BDM, 1995) and those of Serdyuchenko et al. (2014), and Gorshelev et al. (2014), (abbreviated as SER, 2014) were examined for use in atmospheric ozone measurements in the Huggins band. In conclusion, ACSO recommends:(a) The spectroscopic data of BP (1985) should no longer be used for retrieval of atmospheric ozone measurements.(b) For retrieval of ground-based instruments of total ozone and ozone profile measurements by the Umkehr method performed by Brewer and Dobson instruments data of SER (2014) are recommended to be used. When SER (2014) is used, the difference between total ozone measurements of Brewer and Dobson instruments are very small and the difference between Dobson measurements at AD and CD wavelength pairs are diminished.(c) For ground-based Light Detection and Ranging (LIDAR) measurements the use of BDM (1995) or SER (2014) is recommended.(d) For satellite retrieval the presently widely used data of BDM (1995) should be used because SER (2014) seems less suitable for retrievals that use wavelengths close to 300 nm due to a deficiency in the signal-to-noise ratio in the SER (2014) dataset.The work of ACSO also showed: The need to continue laboratory cross-section measurements of ozone of highest quality. The importance of careful characterization of the uncertainties of the laboratory measurements. The need to extend the scope of such studies to other wavelength ranges (particularly to cover not only the Huggins band but also the comparison with the mid-infrared region). The need for regular cooperation of experts in spectral laboratory measurements and specialists in atmospheric (ozone) measurements.
Richter, Christiane; Kotz, Frederik; Giselbrecht, Stefan; Helmer, Dorothea; Rapp, Bastian E
2016-06-01
The fluid mechanics of microfluidics is distinctively simpler than the fluid mechanics of macroscopic systems. In macroscopic systems effects such as non-laminar flow, convection, gravity etc. need to be accounted for all of which can usually be neglected in microfluidic systems. Still, there exists only a very limited selection of channel cross-sections for which the Navier-Stokes equation for pressure-driven Poiseuille flow can be solved analytically. From these equations, velocity profiles as well as flow rates can be calculated. However, whenever a cross-section is not highly symmetric (rectangular, elliptical or circular) the Navier-Stokes equation can usually not be solved analytically. In all of these cases, numerical methods are required. However, in many instances it is not necessary to turn to complex numerical solver packages for deriving, e.g., the velocity profile of a more complex microfluidic channel cross-section. In this paper, a simple spreadsheet analysis tool (here: Microsoft Excel) will be used to implement a simple numerical scheme which allows solving the Navier-Stokes equation for arbitrary channel cross-sections.
Braun, Lindsay M; Rodríguez, Daniel A; Evenson, Kelly R; Hirsch, Jana A; Moore, Kari A; Diez Roux, Ana V
2016-05-01
We used data from 3227 older adults in the Multi-Ethnic Study of Atherosclerosis (2004-2012) to explore cross-sectional and longitudinal associations between walkability and cardiometabolic risk factors. In cross-sectional analyses, linear regression was used to estimate associations of Street Smart Walk Score® with glucose, triglycerides, HDL and LDL cholesterol, systolic and diastolic blood pressure, and waist circumference, while logistic regression was used to estimate associations with odds of metabolic syndrome. Econometric fixed effects models were used to estimate longitudinal associations of changes in walkability with changes in each risk factor among participants who moved residential locations between 2004 and 2012 (n=583). Most cross-sectional and longitudinal associations were small and statistically non-significant. We found limited evidence that higher walkability was cross-sectionally associated with lower blood pressure but that increases in walkability were associated with increases in triglycerides and blood pressure over time. Further research over longer time periods is needed to understand the potential for built environment interventions to improve cardiometabolic health. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Parkinson, W. H.; Yoshino, K.; Freeman, D. E.
1993-01-01
An account is given of progress during the six-month period 1 Nov. 1992 to 30 Apr. 1993 on work on (1) cross section measurements of the Schumann-Runge continuum; (2) the determination of the predissociation linewidths of the Schumann-Runge bands of O2; (3) the determination of the molecular constants of the ground state of O2; (4) cross section measurements of CO2 in wavelength region 120-170 nm; and (4) determination of dissociation energy of O2. The experimental investigations are effected at high resolution with a 6.65 m scanning spectrometer which is, by virtue of its small instrumental width (FWHM = 0.0013 nm), uniquely suitable for cross section measurements of molecular bands with discrete rotational structure. Below 175 nm and in the region of the S-R continuum, synchrotron radiation is suitable for cross section measurements. All of these spectroscopic measurements are needed for accurate calculations of the production of atomic oxygen and penetration of solar radiation into the Earth's atmosphere.
The Effect of New Ozone Cross Sections Applied to SBUV and TOMS Retrievals
NASA Technical Reports Server (NTRS)
McPeters, Richard D.; Labow, Gordon J.
2010-01-01
The ozone cross sections as measured by Bass and Paur have been used for processing of SBUV and TOMS data since 1986. While these cross sections were a big improvement over those previously available, there were known minor problems with accuracy for wavelengths longward of 330 nm and with the temperature dependance. Today's requirements to separate stratospheric ozone from tropospheric ozone and for the derivation of minor species such as BrO and N02 place stringent new requirements on the accuracy needed. The ozone cross section measurements of Brion, Daumont, and Malicet (BDM) are being considered for use in UV-based ozone retrievals. They have much better resolution, an extended wavelength range, and a more consistent temperature dependance. Tests show that BDM retrievals exhibit lower retrieval residuals in the satellite data; i.e., they explain our measured atmospheric radiances more accurately. Total column ozone retrieved by the TOMS instruments is about 1.5% higher than before. Ozone profiles retrieved from SBUV using the new cross sections are lower in the upper stratosphere and higher in the lower stratosphere and troposphere.
Bradu, Adrian; Kapinchev, Konstantin; Barnes, Frederick; Podoleanu, Adrian
2015-07-01
In a previous report, we demonstrated master-slave optical coherence tomography (MS-OCT), an OCT method that does not need resampling of data and can be used to deliver en face images from several depths simultaneously. In a separate report, we have also demonstrated MS-OCT's capability of producing cross-sectional images of a quality similar to those provided by the traditional Fourier domain (FD) OCT technique, but at a much slower rate. Here, we demonstrate that by taking advantage of the parallel processing capabilities offered by the MS-OCT method, cross-sectional OCT images of the human retina can be produced in real time. We analyze the conditions that ensure a true real-time B-scan imaging operation and demonstrate in vivo real-time images from human fovea and the optic nerve, with resolution and sensitivity comparable to those produced using the traditional FD-based method, however, without the need of data resampling.
Open charm production and low x gluons
NASA Astrophysics Data System (ADS)
de Oliveira, E. G.; Martin, A. D.; Ryskin, M. G.
2018-04-01
We compare the rapidity, y , and the beam energy, √{s } , behaviors of the cross section of the data for D meson production in the forward direction that were measured by the LHCb Collaboration. We describe the observed cross sections using NLO perturbative QCD, and choose the optimal factorization scale for the LO contribution which provides the resummation of the large double logarithms. We emphasize the inconsistency observed in the y and √{s } behaviors of the D meson cross sections. The y behavior indicates a very flat x dependence of the gluon PDF in the unexplored low x region around x ˜1 0-5 . However, to describe the √{s } dependence of the data we need a steeper gluon PDF with decreasing x . Moreover, an even steeper behavior is needed to provide an extrapolation which matches on to the well known gluons found in the global PDF analyses for x ˜1 0-3 . The possible role of nonperturbative effects is briefly discussed.
Electron scattering on molecules: search for semi-empirical indications
NASA Astrophysics Data System (ADS)
Fedus, Kamil; Karwasz, Grzegorz P.
2017-06-01
Reliable cross-sections for electron-molecule collisions are urgently needed for numerical modeling of various processes important from technological point of view. Unfortunately, a significant progress in theory and experiment over the last decade is not usually accompanied by the convergence of cross-sections measured at different laboratories and calculated with different methods. Moreover the most advanced contemporary theories involve such large basis sets and complicated equations that they are not easily applied to each specific molecule for which data are needed. For these reasons the search for semi-empirical indications in angular and energy dependencies of scattering cross-section becomes important. In this paper we make a brief review of the applicability of the Born-dipole approximation for elastic, rotational, vibrational and ionization processes that can occur during electron-molecule collisions. We take into account the most recent experimental findings as the reference points. Contribution to the Topical Issue "Atomic and Molecular Data and Their Applications", edited by Gordon W.F. Drake, Jung-Sik Yoon, Daiji Kato, and Grzegorz Karwasz.
Application of Computer Axial Tomography (CAT) to measuring crop canopy geometry. [corn and soybeans
NASA Technical Reports Server (NTRS)
Bauer, M. E.; Vanderbilt, V. C. (Principal Investigator); Kilgore, R. W.
1981-01-01
The feasibility of using the principles of computer axial topography (CAT) to quantify the structure of crop canopies was investigated because six variables are needed to describe the position-orientation with time of a small piece of canopy foliage. Several cross sections were cut through the foliage of healthy, green corn and soybean canopies in the dent and full pod development stages, respectively. A photograph of each cross section representing the intersection of a plane with the foliage was enlarged and the air-foliage boundaries delineated by the plane were digitized. A computer program was written and used to reconstruct the cross section of the canopy. The approach used in applying optical computer axial tomography to measuring crop canopy geometry shows promise of being able to provide needed geometric information for input data to canopy reflectance models. The difficulty of using the CAT scanner to measure large canopies of crops like corn is discussed and a solution is proposed involving the measurement of plants one at a time.
Evaluation of the Neutron Data Standards
DOE Office of Scientific and Technical Information (OSTI.GOV)
Carlson, A. D.; Pronyaev, V. G.; Capote, R.
With the need for improving existing nuclear data evaluations, (e.g., ENDF/B-VIII.0 and JEFF-3.3 releases) the first step was to evaluate the standards for use in such a library. This new standards evaluation made use of improved experimental data and some developments in the methodology of analysis and evaluation. In addition to the work on the traditional standards, this work produced the extension of some energy ranges and includes new reactions that are called reference cross sections. Since the effort extends beyond the traditional standards, it is called the neutron data standards evaluation. This international effort has produced new evaluations ofmore » the following cross section standards: the H(n,n), 6Li(n,t), 10B(n,α), 10B(n,α 1γ), natC(n,n), Au(n,γ), 235U(n,f) and 238U(n,f). Also in the evaluation process the 238U(n,γ) and 239Pu(n,f) cross sections that are not standards were evaluated. Evaluations were also obtained for data that are not traditional standards: the Maxwellian spectrum averaged cross section for the Au(n,γ) cross section at 30 keV; reference cross sections for prompt γ-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the 252Cf spontaneous fission neutron spectrum and the 235U prompt fission neutron spectrum induced by thermal incident neutrons; and the thermal neutron constants. The data and covariance matrices of the uncertainties were obtained directly from the evaluation procedure.« less
Evaluation of the Neutron Data Standards
Carlson, A. D.; Pronyaev, V. G.; Capote, R.; ...
2018-02-01
With the need for improving existing nuclear data evaluations, (e.g., ENDF/B-VIII.0 and JEFF-3.3 releases) the first step was to evaluate the standards for use in such a library. This new standards evaluation made use of improved experimental data and some developments in the methodology of analysis and evaluation. In addition to the work on the traditional standards, this work produced the extension of some energy ranges and includes new reactions that are called reference cross sections. Since the effort extends beyond the traditional standards, it is called the neutron data standards evaluation. This international effort has produced new evaluations ofmore » the following cross section standards: the H(n,n), 6Li(n,t), 10B(n,α), 10B(n,α 1γ), natC(n,n), Au(n,γ), 235U(n,f) and 238U(n,f). Also in the evaluation process the 238U(n,γ) and 239Pu(n,f) cross sections that are not standards were evaluated. Evaluations were also obtained for data that are not traditional standards: the Maxwellian spectrum averaged cross section for the Au(n,γ) cross section at 30 keV; reference cross sections for prompt γ-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the 252Cf spontaneous fission neutron spectrum and the 235U prompt fission neutron spectrum induced by thermal incident neutrons; and the thermal neutron constants. The data and covariance matrices of the uncertainties were obtained directly from the evaluation procedure.« less
Breakup fusion theory of nuclear reactions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mastroleo, R.C.
1987-01-01
Continuum spectra of particles emitted in incomplete fusion reactions are one of the major interests in current nuclear reaction studies. Based on an idea of the so-called breakup fusion (BF) reaction, several authors derived closed formulas for the singles cross section of the particles that are emitted. There have been presented, however, two conflicting cross section formulas for the same BF reaction. For convenience, we shall call one of them the IAV (Ichimura, Austern and Vincent) and the other UT (Udagawa and Tamura) cross section formulas. In this work, the formulation of the UT cross section formula (prior-form) is presented,more » and the post-form version of the IAV cross section formula is evaluted for a few {alpha}- and d-induced reactions based on the exact finite range method. It is shown that the values thus calculated are larger by an order of magnitude as compared with the experimental cross sections for the {alpha}-induced reactions, while they are comparable with the experimental cross sections for the d-induced reactions. A possible origin of why such a large cross section is resulted in the case of {alpha}-induced reactions is also discussed. Polarization of the residual compound nucleus produced in breakup fusion reactions are calculated and compared with experiments. It is shown that the polarization is rather sensitive to the deflection angles of the strongly absortive partial waves and to obtain a good fit with the experimental data a l-dependent potential in the incident channel is needed in order to stress the lower partial waves.« less
Evaluation of the Neutron Data Standards
NASA Astrophysics Data System (ADS)
Carlson, A. D.; Pronyaev, V. G.; Capote, R.; Hale, G. M.; Chen, Z.-P.; Duran, I.; Hambsch, F.-J.; Kunieda, S.; Mannhart, W.; Marcinkevicius, B.; Nelson, R. O.; Neudecker, D.; Noguere, G.; Paris, M.; Simakov, S. P.; Schillebeeckx, P.; Smith, D. L.; Tao, X.; Trkov, A.; Wallner, A.; Wang, W.
2018-02-01
With the need for improving existing nuclear data evaluations, (e.g., ENDF/B-VIII.0 and JEFF-3.3 releases) the first step was to evaluate the standards for use in such a library. This new standards evaluation made use of improved experimental data and some developments in the methodology of analysis and evaluation. In addition to the work on the traditional standards, this work produced the extension of some energy ranges and includes new reactions that are called reference cross sections. Since the effort extends beyond the traditional standards, it is called the neutron data standards evaluation. This international effort has produced new evaluations of the following cross section standards: the H(n,n), 6Li(n,t), 10B(n,α), 10B(n,α1 γ), natC(n,n), Au(n,γ), 235U(n,f) and 238U(n,f). Also in the evaluation process the 238U(n,γ) and 239Pu(n,f) cross sections that are not standards were evaluated. Evaluations were also obtained for data that are not traditional standards: the Maxwellian spectrum averaged cross section for the Au(n,γ) cross section at 30 keV; reference cross sections for prompt γ-ray production in fast neutron-induced reactions; reference cross sections for very high energy fission cross sections; the 252Cf spontaneous fission neutron spectrum and the 235U prompt fission neutron spectrum induced by thermal incident neutrons; and the thermal neutron constants. The data and covariance matrices of the uncertainties were obtained directly from the evaluation procedure.
NASA Technical Reports Server (NTRS)
Lee, Long C.; Srivastava, Santosh K.
1990-01-01
Electron-impact ionization and electron attachment cross sections of radicals and excited molecules were measured using an apparatus that consists of an electron beam, a molecular beam and a laser beam. The information obtained is needed for the pulse power applications in the areas of high power gaseous discharge switches, high energy lasers, particle beam experiments, and electromagnetic pulse systems. The basic data needed for the development of optically-controlled discharge switches were also investigated. Transient current pulses induced by laser irradiation of discharge media were observed and applied for the study of electron-molecule reaction kinetics in gaseous discharges.
Nuclear model calculations and their role in space radiation research
NASA Technical Reports Server (NTRS)
Townsend, L. W.; Cucinotta, F. A.; Heilbronn, L. H.
2002-01-01
Proper assessments of spacecraft shielding requirements and concomitant estimates of risk to spacecraft crews from energetic space radiation requires accurate, quantitative methods of characterizing the compositional changes in these radiation fields as they pass through thick absorbers. These quantitative methods are also needed for characterizing accelerator beams used in space radiobiology studies. Because of the impracticality/impossibility of measuring these altered radiation fields inside critical internal body organs of biological test specimens and humans, computational methods rather than direct measurements must be used. Since composition changes in the fields arise from nuclear interaction processes (elastic, inelastic and breakup), knowledge of the appropriate cross sections and spectra must be available. Experiments alone cannot provide the necessary cross section and secondary particle (neutron and charged particle) spectral data because of the large number of nuclear species and wide range of energies involved in space radiation research. Hence, nuclear models are needed. In this paper current methods of predicting total and absorption cross sections and secondary particle (neutrons and ions) yields and spectra for space radiation protection analyses are reviewed. Model shortcomings are discussed and future needs presented. c2002 COSPAR. Published by Elsevier Science Ltd. All right reserved.
Frano, Kristen A; Mayhew, Hannah E; Svoboda, Shelley A; Wustholz, Kristin L
2014-12-21
The analysis of paint cross-sections can reveal a remarkable amount of information about the layers and materials in a painting without visibly altering the artwork. Although a variety of analytical approaches are used to detect inorganic pigments as well as organic binders, proteins, and lipids in cross-sections, they do not provide for the unambiguous identification of natural, organic colorants. Here, we develop a novel combined surface-enhanced Raman scattering (SERS), light microscopy, and normal Raman scattering (NRS) approach for the identification of red organic and inorganic pigments in paint cross-sections obtained from historic 18th and 19th century oil paintings. In particular, Ag nanoparticles are directly applied to localized areas of paint cross-sections mounted in polyester resin for SERS analysis of the organic pigments. This combined extractionless non-hydrolysis SERS and NRS approach provides for the definitive identification of carmine lake, madder lake, and vermilion in multiple paint layers. To our knowledge, this study represents the first in situ identification of natural, organic pigments within paint cross-sections from oil paintings. Furthermore, the combination of SERS and normal Raman, with light microscopy provides conservators with a more comprehensive understanding of a painting from a single sample and without the need for sample pretreatment.
Martín-Hernández, G; Mastinu, P F; Praena, J; Dzysiuk, N; Capote Noy, R; Pignatari, M
2012-08-01
The need of neutron capture cross section measurements for astrophysics motivates present work, where calculations to generate stellar neutron spectra at different temperatures are performed. The accelerator-based (7)Li(p,n)(7)Be reaction is used. Shaping the proton beam energy and the sample covering a specific solid angle, neutron activation for measuring stellar-averaged capture cross section can be done. High-quality Maxwell-Boltzmann neutron spectra are predicted. Assuming a general behavior of the neutron capture cross section a weighted fit of the spectrum to Maxwell-Boltzmann distributions is successfully introduced. Copyright © 2012 Elsevier Ltd. All rights reserved.
Cross Section High Resolution Imaging of Polymer-Based Materials
NASA Astrophysics Data System (ADS)
Delaportas, D.; Aden, P.; Muckle, C.; Yeates, S.; Treutlein, R.; Haq, S.; Alexandrou, I.
This paper describes a methodology for preparing cross sections of organic layers suitable for transmission electron microscopy (TEM) at high resolution. Our principal aim is to prepare samples that are tough enough to allow the slicing into sub-150 nm sections. We also need strong contrast at the organic layer area to make it identifiable during TEM. Our approach is to deposit organic layers on flexible substrates and prepare thin cross sections using ultra-microtomy. We sandwich the organic layer between two metal thin films in order to isolate it and improve contrast. Our methodology is used to study the microstructure of polymer/nanotube composites, allowing us to accurately measure the organic layer thickness, determine nanotube dispersion and assess the effect of nanotube clustering on film structural stability.
Elastic and inelastic neutron scattering cross sections for 12C at En = 5.9, 6.1, and 7.0 MeV
NASA Astrophysics Data System (ADS)
Lyons, Elizabeth; Hicks, Sally; Morin, Theodore; Derdeyn, Elizabeth; Peters, Erin
2017-09-01
Measurements of neutron elastic and inelastic scattering differential cross sections from 12C have been performed at incident neutron energies of 5.9, 6.1, and 7.0 MeV. Comparisons of existing experimental cross sections (NNDC) at these incident neutron energies reveal large discrepancies. Accurate measurements of 12C cross sections are vital to facilitate precise calculations regarding criticality conditions for nuclear reactors, advances in security screening methods, and better understanding astrophysical and nuclear phenomenon. During preliminary measurements of 12C cross sections at the University of Kentucky Accelerator Laboratory (UKAL), we realized the relative efficiency of the deuterated benzene (main) detector was needed over an unusually large range of neutron energies due to the high Q value of the first excited state of 12C. Those experiments were repeated during the summer of 2017 to measure in situ the relative detector efficiency with better beam conditions and a better understanding of background observed from the 2H(d, n)3He source reaction. The resulting improved detector efficiency was used in determining the neutron elastic and inelastic scattering cross sections. While the former were found to be in excellent agreement with evaluated cross sections from ENDF, the latter show some discrepancies, especially at 6.1 MeV. Our results will be presented. Research is supported by USDOE-NNSA-SSAP: NA0002931, NSF: PHY-1606890, and the Donald A. Cowan Physics Institute at the University of Dallas.
NASA Astrophysics Data System (ADS)
Bilsley, N. A.; Cook, H. M.
2016-12-01
Although most geology students feel the joy of interpreting geologic cross sections, few experience the challenges career geologists face in order to create these visual representations. Without a hefty budget and a drill rig, students generally miss out on the challenge of extrapolating subsurficial features from limited datasets, and jump to narrating geologic time through beautifully pre-drawn cross sections. Although this method allows students to practice relative dating techniques, they miss the practical step of learning how we have come to understand what the subsurface looks like in the first place. This activity was designed to close that gap, while giving students the opportunity to engage in peer learning by strategizing in groups, critiquing each other's work, and evaluating their own work. Broken into groups, students are instructed to create a geologic cross section that must include specific structural features. The cross sections are traded with another group, who reviews and provides feedback on the drawing before returning it back to the original group. The feedback is reviewed and incorporated, before the cross sections are colored and covered with black coated, clear scratch-art paper. The hidden cross sections are traded with a new group, who must decide where and how deep to scratch, or "core", on their cross section. Utilizing the data obtained from the cores, the students interpret and draw a new cross section. Finally, the scratch-art paper is removed, and the original cross section revealed. The differences between the original and interpreted subsurface as well as evaluation of sampling methods (e.g. location and depth of cores) are discussed within the groups and with the class. This activity bridges the gap between developing the intuition needed to create cross sections with realistic geoscientific techniques and utilizing cross sections to understand geologic time. In addition, not only does the activity require few supplies and minimal time of the instructor, but its peer-based learning approach stimulates creativity, allows students to effectively generate and communicate constructive feedback, and encourages students to evaluate and critique their methods and assumptions.
Time Evolution of Meson Density During Formation of Expanding Quark-Antiquark System
NASA Astrophysics Data System (ADS)
Ghaffary, Tooraj
2018-04-01
Recently some researchers (Sepehri and Shoorvazi Astrophys. Spaces Sci. 344(2), 521-527, 2013) have considered the Universe as an acceleration cylindrical system. Motivated by their work and using their method in QCD, this paper has been cleared that because the acceleration of expansion in quark-antiquark system is relatively very large, one horizon is appeared outside the system. To obtain the total cross section of meson near this horizon, we need to multiply the production cross section for appeared horizon by the density of meson produced outside the system. As it can be seen by an observer who is outside the meson formation process, this cross section depends on time so the event horizon is now a time depended process.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguado, Alfredo; Roncero, Octavio; Zanchet, Alexandre
The impact of the photodissociation of HCN and HNC isomers is analyzed in different astrophysical environments. For this purpose, the individual photodissociation cross sections of HCN and HNC isomers have been calculated in the 7–13.6 eV photon energy range for a temperature of 10 K. These calculations are based on the ab initio calculation of three-dimensional adiabatic potential energy surfaces of the 21 lower electronic states. The cross sections are then obtained using a quantum wave packet calculation of the rotational transitions needed to simulate a rotational temperature of 10 K. The cross section calculated for HCN shows significant differencesmore » with respect to the experimental one, and this is attributed to the need to consider non-adiabatic transitions. Ratios between the photodissociation rates of HCN and HNC under different ultraviolet radiation fields have been computed by renormalizing the rates to the experimental value. It is found that HNC is photodissociated faster than HCN by a factor of 2.2 for the local interstellar radiation field and 9.2 for the solar radiation field, at 1 au. We conclude that to properly describe the HNC/HCN abundance ratio in astronomical environments illuminated by an intense ultraviolet radiation field, it is necessary to use different photodissociation rates for each of the two isomers, which are obtained by integrating the product of the photodissociation cross sections and ultraviolet radiation field over the relevant wavelength range.« less
Electron-neutrino scattering off nuclei from two different theoretical perspectives
NASA Astrophysics Data System (ADS)
Martini, M.; Jachowicz, N.; Ericson, M.; Pandey, V.; Van Cuyck, T.; Van Dessel, N.
2016-07-01
We analyze charged-current electron-neutrino cross sections on carbon. We consider two different theoretical approaches, on one hand the continuum random phase approximation (CRPA) which allows a description of giant resonances and quasielastic excitations, on the other hand the RPA-based calculations which are able to describe multinucleon emission and coherent and incoherent pion production as well as quasielastic excitations. We compare the two approaches in the genuine quasielastic channel, and find a satisfactory agreement between them at large energies while at low energies the collective giant resonances show up only in the CRPA approach. We also compare electron-neutrino cross sections with the corresponding muon-neutrino ones in order to investigate the impact of the different charged-lepton masses. Finally, restricting to the RPA-based approach, we compare the sum of quasielastic, multinucleon emission, coherent, and incoherent one-pion production cross sections (folded with the electron-neutrino T2K flux) with the charged-current inclusive electron-neutrino differential cross sections on carbon measured by T2K. We find a good agreement with the data. The multinucleon component is needed in order to reproduce the T2K electron-neutrino inclusive cross sections.
NASA Astrophysics Data System (ADS)
Horst, Felix; Schuy, Christoph; Weber, Uli; Brinkmann, Kai-Thomas; Zink, Klemens
2017-08-01
4He ions are considered to be used for hadron radiotherapy due to their favorable physical and radiobiological properties. For an accurate dose calculation the fragmentation of the primary 4He ions occurring as a result of nuclear collisions must be taken into account. Therefore precise nuclear reaction models need to be implemented in the radiation transport codes used for dose calculation. A fragmentation experiment using thin graphite targets was conducted at the Heidelberg Ion Beam Therapy Center (HIT) to obtain new and precise 4He-nucleus cross section data in the clinically relevant energy range. Measured values for the charge-changing cross section, mass-changing cross section, as well as the inclusive 3He production cross section for 4He+12C collisions at energies between 80 and 220 MeV /u are presented. These data are compared to the 4He-nucleus reaction model by DeVries and Peng as well as to the parametrizations by Tripathi et al. and by Cucinotta et al., which are implemented in the treatment planning code trip98 and several other radiation transport codes.
NASA Astrophysics Data System (ADS)
Sakarya, Doǧan Uǧur
2017-05-01
Drag force effect is an important aspect of range performance in missile applications especially for long flight time. However, old fashioned gimbal approaches force to increase missile diameter. This increase has negative aspect of rising in both drag force and radar cross sectional area. A new gimbal approach was proposed recently. It uses a beam steering optical arrangement. Therefore, it needs less volume envelope for same field of regard and same optomechanical assembly than the old fashioned gimbal approaches. In addition to longer range performance achieved with same fuel in the new gimbal approach, this method provides smaller cross sectional area which can be more invisible in enemies' radar. In this paper, the two gimbal approaches - the old fashioned one and the new one- are compared in order to decrease drag force and radar cross sectional area in missile application. In this study; missile parameters are assumed to generate gimbal and optical design parameters. Optical design is performed according to these missile criteria. Two gimbal configurations are designed with respect to modeled missile parameters. Also analyzes are performed to show decreased drag force and radar cross sectional area in the new approach for comparison.
ERIC Educational Resources Information Center
Hassiotis, A.; Turk, J.
2012-01-01
Background: Little research has been conducted on the mental health needs of adolescents with intellectual disability, despite the severity and rates of such needs being high throughout childhood and in adulthood. We have investigated the prevalence and predictors of mental health needs and service use in adolescents with intellectual…
Unmet Health Care Needs in Children with Cerebral Palsy: A Cross-Sectional Study
ERIC Educational Resources Information Center
Jackson, Katie E.; Krishnaswami, Shanthi; McPheeters, Melissa
2011-01-01
Children with potentially severe health conditions such as cerebral palsy (CP) are at risk for unmet health care needs. We sought to determine whether children with CP had significantly greater unmet health care needs than children with other special health care needs (SHCN), and whether conditions associated with CP increased the odds of unmet…
Precise 238U(n,2n)237U reaction cross-section measurements using the activation facility at TUNL
NASA Astrophysics Data System (ADS)
Krishichayan, Fnu; Bhike, M.; Tornow, W.
2014-09-01
Accurate neutron-induced 238U(n,2n)237U reaction data are required for many practical applications, especially in the field of nuclear energy, including advanced heavy water reactors, where 238U is used as the breeding material to regenerate the fissile material 239Pu. Precise (n,2n) cross-section measurements of 238U are underway at TUNL with mono-energetic neutrons in the 8.0 to 14.0 MeV energy range in steps of 0.25 MeV using the activation technique. After activation of the 0.5 inch diameter and 442 mg 238U foil, the activity of the 208 keV characteristic γ-line is tracked for 6 weeks with a high efficient HPGe clover detector to determine the initial activity needed for the cross-section determination. Results of the cross-section measurements, determined relative to 27Al and 197Au neutron activation monitor foils, and the comparison with theoretical models will be presented during the meeting.
Savukov, I. M.; Filin, D. V.
2014-12-29
Many applications are in need of accurate photoionization cross sections, especially in the case of complex atoms. Configuration-interaction relativistic-many-body-perturbation theory (CI-RMBPT) has been successful in predicting atomic energies, matrix elements between discrete states, and other properties, which is quite promising, but it has not been applied to photoionization problems owing to extra complications arising from continuum states. In this paper a method that will allow the conversion of discrete CI-(R)MPBT oscillator strengths (OS) to photoionization cross sections with minimal modifications of the codes is introduced and CI-RMBPT cross sections of Ne, Ar, Kr, and Xe are calculated. A consistent agreementmore » with experiment is found. RMBPT corrections are particularly significant for Ar, Kr, and Xe and improve agreement with experimental results compared to the particle-hole CI method. As a result, the demonstrated conversion method can be applied to CI-RMBPT photoionization calculations for a large number of multivalence atoms and ions.« less
NASA Technical Reports Server (NTRS)
Parkinson, W. H.; Yoshino, K.
1999-01-01
We have studied the spectroscopy and the cross sections of the simple molecules of atmospheric interest such as oxygen, nitric oxide, carbon dioxide, and water. We have made cross section measurements on an absolute base without the effects from the limited instrumental resolution. We have used the following different instruments- the grating spectrometer (6.65-m at CfA, 3-m at Photon Factory), VUV Fourier transform spectrometer at Imperial College, and then moved the same one to the Photon Factory. Selection of the instruments depend on the appearance of molecular bands, and their wavelength region. For example, the cross section measurements of Doppler limited bands can been done with the Fourier transform spectrometer at the very high resolution (0.025/ cm resolution). All of these spectroscopic measurements are needed for accurate calculations of the production of atomic oxygen penetration of solar radiation into the Earth's atmosphere, and photochemistry of minor molecules.
Prospects for Precision Neutrino Cross Section Measurements
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, Deborah A.
2016-01-28
The need for precision cross section measurements is more urgent now than ever before, given the central role neutrino oscillation measurements play in the field of particle physics. The definition of precision is something worth considering, however. In order to build the best model for an oscillation experiment, cross section measurements should span a broad range of energies, neutrino interaction channels, and target nuclei. Precision might better be defined not in the final uncertainty associated with any one measurement but rather with the breadth of measurements that are available to constrain models. Current experience shows that models are better constrainedmore » by 10 measurements across different processes and energies with 10% uncertainties than by one measurement of one process on one nucleus with a 1% uncertainty. This article describes the current status of and future prospects for the field of precision cross section measurements considering the metric of how many processes, energies, and nuclei have been studied.« less
Psychosocial Support Issues Affecting Older Patients: A Cross-sectional Paramedic Perspective.
Ross, Linda; Jennings, Paul; Williams, Brett
2017-01-01
This research aimed to gain an understanding of the psychosocial support needs of older patients in the out-of-hospital setting from the perspective of paramedics. Specifically, we investigate if and how paramedics are able to meet the needs of older adults, and the barriers preventing them from achieving this. This study was a cross-sectional study utilizing a sequential design with both quantitative and qualitative methodologies. All participants agreed or strongly agreed that older patients have needs beyond the physical and that they would like to do more for older patients. Paramedics discussed that psychosocial support issues are rarely in isolation and straightforward but were often coupled with broader, longer term physical health and social support issues. They would like to be able to do more for patients but feel hamstrung by lack of time, resources, and know-how.
Khalil, Mohammed K; Paas, Fred; Johnson, Tristan E; Su, Yung K; Payer, Andrew F
2008-01-01
This research is an effort to best utilize the interactive anatomical images for instructional purposes based on cognitive load theory. Three studies explored the differential effects of three computer-based instructional strategies that use anatomical cross-sections to enhance the interpretation of radiological images. These strategies include: (1) cross-sectional images of the head that can be superimposed on radiological images, (2) transparent highlighting of anatomical structures in radiological images, and (3) cross-sectional images of the head with radiological images presented side-by-side. Data collected included: (1) time spent on instruction and on solving test questions, (2) mental effort during instruction and test, and (3) students' performance to identify anatomical structures in radiological images. Participants were 28 freshmen medical students (15 males and 13 females) and 208 biology students (190 females and 18 males). All studies used posttest-only control group design, and the collected data were analyzed by either t test or ANOVA. In self-directed computer-based environments, the strategies that used cross sections to improve students' ability to recognize anatomic structures in radiological images showed no significant positive effects. However, when increasing the complexity of the instructional materials, cross-sectional images imposed a higher cognitive load, as indicated by higher investment of mental effort. There is not enough evidence to claim that the simultaneous combination of cross sections and radiological images has no effect on the identification of anatomical structures in radiological images for novices. Further research that control for students' learning and cognitive style is needed to reach an informative conclusion.
NASA Technical Reports Server (NTRS)
Ko, William L.; Richards, W. Lance; Fleischer, Van Tran
2009-01-01
The Ko displacement theory, formulated for weak nonuniform (slowly changing cross sections) cantilever beams, was applied to the deformed shape analysis of the doubly-tapered wings of the Ikhana unmanned aircraft. The two-line strain-sensing system (along the wingspan) was used for sensing the bending strains needed for the wing-deformed shapes (deflections and cross-sectional twist) analysis. The deflection equation for each strain-sensing line was expressed in terms of the bending strains evaluated at multiple numbers of strain-sensing stations equally spaced along the strain-sensing line. For the preflight shape analysis of the Ikhana wing, the strain data needed for input to the displacement equations for the shape analysis were obtained from the nodal-stress output of the finite-element analysis. The wing deflections and cross-sectional twist angles calculated from the displacement equations were then compared with those computed from the finite-element computer program. The Ko displacement theory formulated for weak nonlinear cantilever beams was found to be highly accurate in the deformed shape predictions of the doubly-tapered Ikhana wing.
Hongal, S; Torwane, Na; Chandrashekhar, Br; Saxena, V; Chavan, Kr
2014-11-01
Eunuchs are considered as the most vulnerable, frustrated, and insecure community. The accessibility to medical and dental facilities for the eunuchs is nearly nonexistent. Due to these reasons, they might be at a high risk of developing severe dental problems like tooth loss. The present cross-sectional study aimed to evaluate the dental prosthetic status and prosthetic needs among eunuchs residing in Bhopal city, Madhya Pradesh, India. On the basis of convenient nonprobability snowball sampling technique, all the self-identified eunuchs residing in the city of Bhopal along with a matched control consisting of cross section of the general population residing in the same locality was examined to evaluate the prosthetic status and prosthetic needs of the population. All the obtained data were entered into a personal computer on Microsoft excel sheet and analyzed using the software; Statistical Package for Social Science version 20. Data comparison was done by applying Chi-square test. A total of 639 subjects comprised of 207 eunuchs, 218 males and 214 females. Among all participants, 2.8% (18/639) were having prosthesis. The overall prosthetic status among males was 3.2% (7/218) followed by 2.9% (6/207) eunuchs and 2.3% (5/214) females. However, need for multi-unit and combination of one and more unit prosthesis for upper and lower jaws was higher in males compared to females and eunuchs, but the difference was not statistically significant. The findings of this study clearly demonstrate a high unmet need for prosthetic care among the population surveyed.
Sebire, Simon J; Jago, Russell; Fox, Kenneth R; Edwards, Mark J; Thompson, Janice L
2013-09-26
Understanding children's physical activity motivation, its antecedents and associations with behavior is important and can be advanced by using self-determination theory. However, research among youth is largely restricted to adolescents and studies of motivation within certain contexts (e.g., physical education). There are no measures of self-determination theory constructs (physical activity motivation or psychological need satisfaction) for use among children and no previous studies have tested a self-determination theory-based model of children's physical activity motivation. The purpose of this study was to test the reliability and validity of scores derived from scales adapted to measure self-determination theory constructs among children and test a motivational model predicting accelerometer-derived physical activity. Cross-sectional data from 462 children aged 7 to 11 years from 20 primary schools in Bristol, UK were analysed. Confirmatory factor analysis was used to examine the construct validity of adapted behavioral regulation and psychological need satisfaction scales. Structural equation modelling was used to test cross-sectional associations between psychological need satisfaction, motivation types and physical activity assessed by accelerometer. The construct validity and reliability of the motivation and psychological need satisfaction measures were supported. Structural equation modelling provided evidence for a motivational model in which psychological need satisfaction was positively associated with intrinsic and identified motivation types and intrinsic motivation was positively associated with children's minutes in moderate-to-vigorous physical activity. The study provides evidence for the psychometric properties of measures of motivation aligned with self-determination theory among children. Children's motivation that is based on enjoyment and inherent satisfaction of physical activity is associated with their objectively-assessed physical activity and such motivation is positively associated with perceptions of psychological need satisfaction. These psychological factors represent potential malleable targets for interventions to increase children's physical activity.
Characterizing the astrophysical S factor for 12C+12C fusion with wave-packet dynamics
NASA Astrophysics Data System (ADS)
Diaz-Torres, Alexis; Wiescher, Michael
2018-05-01
A quantitative study of the astrophysically important subbarrier fusion of 12C+12C is presented. Low-energy collisions are described in the body-fixed reference frame using wave-packet dynamics within a nuclear molecular picture. A collective Hamiltonian drives the time propagation of the wave packet through the collective potential-energy landscape. The fusion imaginary potential for specific dinuclear configurations is crucial for understanding the appearance of resonances in the fusion cross section. The theoretical subbarrier fusion cross sections explain some observed resonant structures in the astrophysical S factor. These cross sections monotonically decline towards stellar energies. The structures in the data that are not explained are possibly due to cluster effects in the nuclear molecule, which need to be included in the present approach.
An instrument for monitoring stump oedema and shrinkage in amputees.
Fernie, G R; Holliday, P J; Lobb, R J
1978-08-01
A new system for measuring the cross-sectional area profiles of amputation stumps and whole limbs has been designed at the Amputee Research Centre. The instrument consists of a cylindrical tank supported on an elevator. The tank is raised to the height of the amputation stump and filled with water. A graph of the cross-sectional area profile of the amputation stump is generated by a mini-computer as the elevator descends. The cross-sectional area (A) is calculated from the expression: formula: (see text) where Hw = height of water in the tank He = height of the elevator Ac = a constant, related to the size of the measuring tank. This paper describes the instrument, which may find application in many other areas where there is a need to study shape.
NASA Astrophysics Data System (ADS)
Khan, Urooj; Tuteja, Narendra; Ajami, Hoori; Sharma, Ashish
2014-05-01
While the potential uses and benefits of distributed catchment simulation models is undeniable, their practical usage is often hindered by the computational resources they demand. To reduce the computational time/effort in distributed hydrological modelling, a new approach of modelling over an equivalent cross-section is investigated where topographical and physiographic properties of first-order sub-basins are aggregated to constitute modelling elements. To formulate an equivalent cross-section, a homogenization test is conducted to assess the loss in accuracy when averaging topographic and physiographic variables, i.e. length, slope, soil depth and soil type. The homogenization test indicates that the accuracy lost in weighting the soil type is greatest, therefore it needs to be weighted in a systematic manner to formulate equivalent cross-sections. If the soil type remains the same within the sub-basin, a single equivalent cross-section is formulated for the entire sub-basin. If the soil type follows a specific pattern, i.e. different soil types near the centre of the river, middle of hillslope and ridge line, three equivalent cross-sections (left bank, right bank and head water) are required. If the soil types are complex and do not follow any specific pattern, multiple equivalent cross-sections are required based on the number of soil types. The equivalent cross-sections are formulated for a series of first order sub-basins by implementing different weighting methods of topographic and physiographic variables of landforms within the entire or part of a hillslope. The formulated equivalent cross-sections are then simulated using a 2-dimensional, Richards' equation based distributed hydrological model. The simulated fluxes are multiplied by the weighted area of each equivalent cross-section to calculate the total fluxes from the sub-basins. The simulated fluxes include horizontal flow, transpiration, soil evaporation, deep drainage and soil moisture. To assess the accuracy of equivalent cross-section approach, the sub-basins are also divided into equally spaced multiple hillslope cross-sections. These cross-sections are simulated in a fully distributed settings using the 2-dimensional, Richards' equation based distributed hydrological model. The simulated fluxes are multiplied by the contributing area of each cross-section to get total fluxes from each sub-basin referred as reference fluxes. The equivalent cross-section approach is investigated for seven first order sub-basins of the McLaughlin catchment of the Snowy River, NSW, Australia, and evaluated in Wagga-Wagga experimental catchment. Our results show that the simulated fluxes using an equivalent cross-section approach are very close to the reference fluxes whereas computational time is reduced of the order of ~4 to ~22 times in comparison to the fully distributed settings. The transpiration and soil evaporation are the dominant fluxes and constitute ~85% of actual rainfall. Overall, the accuracy achieved in dominant fluxes is higher than the other fluxes. The simulated soil moistures from equivalent cross-section approach are compared with the in-situ soil moisture observations in the Wagga-Wagga experimental catchment in NSW, and results found to be consistent. Our results illustrate that the equivalent cross-section approach reduces the computational time significantly while maintaining the same order of accuracy in predicting the hydrological fluxes. As a result, this approach provides a great potential for implementation of distributed hydrological models at regional scales.
Psychosocial Support Issues Affecting Older Patients: A Cross-sectional Paramedic Perspective
Ross, Linda; Jennings, Paul; Williams, Brett
2017-01-01
This research aimed to gain an understanding of the psychosocial support needs of older patients in the out-of-hospital setting from the perspective of paramedics. Specifically, we investigate if and how paramedics are able to meet the needs of older adults, and the barriers preventing them from achieving this. This study was a cross-sectional study utilizing a sequential design with both quantitative and qualitative methodologies. All participants agreed or strongly agreed that older patients have needs beyond the physical and that they would like to do more for older patients. Paramedics discussed that psychosocial support issues are rarely in isolation and straightforward but were often coupled with broader, longer term physical health and social support issues. They would like to be able to do more for patients but feel hamstrung by lack of time, resources, and know-how. PMID:28965434
van de Ven, Hardy A; Brouwer, Sandra; Koolhaas, Wendy; Goudswaard, Anneke; de Looze, Michiel P; Kecklund, Göran; Almansa, Josue; Bültmann, Ute; van der Klink, Jac J L
2016-09-01
In this cross-sectional study associations were examined between eight shift schedule characteristics with shift-specific sleep complaints and need for recovery and generic health and performance measures. It was hypothesized that shift schedule characteristics meeting ergonomic recommendations are associated with better sleep, need for recovery, health and performance. Questionnaire data were collected from 491 shift workers of 18 companies with 9 regular (semi)-continuous shift schedules. The shift schedule characteristics were analyzed separately and combined using multilevel linear regression models. The hypothesis was largely not confirmed. Relatively few associations were found, of which the majority was in the direction as expected. In particular early starts of morning shifts and many consecutive shifts seem to be avoided. The healthy worker effect, limited variation between included schedules and the cross-sectional design might explain the paucity of significant results. Copyright © 2016 Elsevier Ltd. All rights reserved.
Recognizing the Needs of the Homeless.
ERIC Educational Resources Information Center
France, Joseph B.
This paper summarizes reports and research on the homeless in the United States, presents findings of a survey of Red Cross chapters on services to the homeless, and describes programs for the homeless of selected Red Cross chapters. Section 1 discusses definitions of homelessness and methodologies used to count homeless people. The homeless are…
Van Meerbeek, B; Conn, L J; Duke, E S; Schraub, D; Ghafghaichi, F
1995-03-01
focused ion-beam (FIB) etching, commonly used as a cross-sectioning technique for failure analysis of semiconductor devices, has recently been applied to biological tissues to expose their ultrastructure for examination. It was the aim of this investigation to determine the practical utility of FIB to cross-section resin-dentin interfaces in order to morphologically evaluate the completeness of resin penetration into the exposed collagen scaffold at the resin-dentin bond interface. Two representative commercially available dentin adhesive systems were bonded to mid-coronal dentin. After appropriate fixation and dehydration of the resin-bonded dentin samples, a scanned focused ion-beam of a few tens of nano-meters in diameter was used to cross=section the resin-dentin interface. Examination of the interfacial ultrastructure was accomplished using a field-emission SEM. Results indicate possible artifact production at the cross-sectioned interface, hiding its actual ultrastructure, probably due to a heat-effect with possible recrystallization. Further studies of FIB are needed to optimize its usefulness for resin-dentin interface examinations and other biological tissue applications. Complete resin saturation of the demineralized dentin surface-layer has been claimed to be the key factor for a long-lasting resin-dentin bond. A "clean" artifact-free micro-cross-sectioning technique may provide indisputable ultra-structural information about the depth of resin penetration into the demineralized zone. Such a test would be useful in the development of dentin adhesive systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Schinke, R.; Korsch, H.J.; Poppe, D.
1982-12-15
Rainbow structures in rotationally elastic and inelastic differential cross sections in atom--diatom collisions are investigated by comparison of three model potential energy surfaces labeled I, II, and III which are represented by V(R,..gamma..) = V/sub 0/(R)+V/sub 2/(R)P/sub 2/(cos ..gamma..). The cross sections are calculated within the quantal infinite-order-sudden (IOS) approximation. The anisotropic part V/sub 2/ is the same for all potentials and purely repulsive. The isotropic part V/sub 0/ for potential I is also repulsive and the differential cross sections show the well-studied rotational rainbow structures. Structural changes occur for collisions in potential II and III which have V/sub 0/more » terms being attractive at intermediate and large atom--molecule separations and having well depths of 10% and 25% of the collision energy, respectively. For example, the elastic cross section has no classical rainbow in the case of potential I but three in the case of potential III. The rainbow structures are analyzed within the classical and semiclassical versions of the IOS approximation and interpreted in terms of catastrophe theory. The quantitative comparison of the classical with the quantal IOS cross sections manifests possible quantum effects, i.e., tunneling into nonclassical regions and interference effects due to the superposition of several contributions (up to six in the present study). They can be very prominent and thus we conclude that much caution is needed if experimental data are compared with classical calculations. The accuracy of the IOS approximation is tested by comparison of classical IOS cross sections with cross sections obtained from exact classical trajectory calculations. The agreement is generally good with the exemption of the rainbow region and small angle, rotationally elastic scattering.« less
Karlsson, Anette; Leinhard, Olof Dahlqvist; Åslund, Ulrika; West, Janne; Romu, Thobias; Smedby, Örjan; Zsigmond, Peter; Peolsson, Anneli
2016-10-01
Study Design Cross-sectional study. Background Findings of fat infiltration in cervical spine multifidus, as a sign of degenerative morphometric changes due to whiplash injury, need to be verified. Objectives To develop a method using water/fat magnetic resonance imaging (MRI) to investigate fat infiltration and cross-sectional area of multifidus muscle in individuals with whiplash-associated disorders (WADs) compared to healthy controls. Methods Fat infiltration and cross-sectional area in the multifidus muscles spanning the C4 to C7 segmental levels were investigated by manual segmentation using water/fat-separated MRI in 31 participants with WAD and 31 controls, matched for age and sex. Results Based on average values for data spanning C4 to C7, participants with severe disability related to WAD had 38% greater muscular fat infiltration compared to healthy controls (P = .03) and 45% greater fat infiltration compared to those with mild to moderate disability related to WAD (P = .02). There were no significant differences between those with mild to moderate disability and healthy controls. No significant differences between groups were found for multifidus cross-sectional area. Significant differences were observed for both cross-sectional area and fat infiltration between segmental levels. Conclusion Participants with severe disability after a whiplash injury had higher fat infiltration in the multifidus compared to controls and to those with mild/moderate disability secondary to WAD. Earlier reported findings using T1-weighted MRI were reproduced using refined imaging technology. The results of the study also indicate a risk when segmenting single cross-sectional slices, as both cross-sectional area and fat infiltration differ between cervical levels. J Orthop Sports Phys Ther 2016;46(10):886-893. Epub 2 Sep 2016. doi:10.2519/jospt.2016.6553.
NASA Astrophysics Data System (ADS)
Aguado, Alfredo; Roncero, Octavio; Zanchet, Alexandre; Agúndez, Marcelino; Cernicharo, José
2017-03-01
The impact of the photodissociation of HCN and HNC isomers is analyzed in different astrophysical environments. For this purpose, the individual photodissociation cross sections of HCN and HNC isomers have been calculated in the 7-13.6 eV photon energy range for a temperature of 10 K. These calculations are based on the ab initio calculation of three-dimensional adiabatic potential energy surfaces of the 21 lower electronic states. The cross sections are then obtained using a quantum wave packet calculation of the rotational transitions needed to simulate a rotational temperature of 10 K. The cross section calculated for HCN shows significant differences with respect to the experimental one, and this is attributed to the need to consider non-adiabatic transitions. Ratios between the photodissociation rates of HCN and HNC under different ultraviolet radiation fields have been computed by renormalizing the rates to the experimental value. It is found that HNC is photodissociated faster than HCN by a factor of 2.2 for the local interstellar radiation field and 9.2 for the solar radiation field, at 1 au. We conclude that to properly describe the HNC/HCN abundance ratio in astronomical environments illuminated by an intense ultraviolet radiation field, it is necessary to use different photodissociation rates for each of the two isomers, which are obtained by integrating the product of the photodissociation cross sections and ultraviolet radiation field over the relevant wavelength range.
A five-year review of vertical HIV transmission in a specialized service: cross-sectional study.
Hoffmann, Izabel Cristina; Santos, Wendel Mombaque Dos; Padoin, Stela Maris de Mello; Barros, Sonia Maria Oliveira de
2016-01-01
Healthcare professionals need to instill the process of prevention, control and treatment of people infected with HIV into care practice. Through maintaining preventive treatment among HIV-infected pregnant women, it has been demonstrated that prophylactic antiretroviral therapy, scheduled cesarean section and the prohibition of breastfeeding significantly reduce vertical HIV transmission. This study aimed to assess the rates of vertical HIV transmission in a specialized service and identify the factors associated with it. Cross-sectional study developed at the University Hospital of Santa Maria (RS), Brazil. A cross-sectional study was conducted on a sample of 198 notification forms and medical records of HIV-positive pregnant women and exposed children. The vertical transmission rate was 2.4%, and three children had been infected by vertical HIV transmission. The statistically significant risk factor was the use of injectable drugs. Delayed reporting of pregnancy, absence of antiretroviral therapy during pregnancy, lack of proper prenatal care, incapacity to perform viral load detection tests and CD4+ T cell counts and obstetric and maternal clinical complications were reported. The vertical transmission rate was high and the recommended intervention measures were not adopted in full. Adequate prophylactic measures need to be implemented in HIV-positive pregnant women prenatally and during the antenatal, delivery and postpartum periods.
Study of the Integration of the CNU-TS-1 Mobile Tunnel Monitoring System.
Du, Liming; Zhong, Ruofei; Sun, Haili; Zhu, Qiang; Zhang, Zhen
2018-02-01
A rapid, precise and automated means for the regular inspection and maintenance of a large number of tunnels is needed. Based on the depth study of the tunnel monitoring method, the CNU-TS-1 mobile tunnel monitoring system (TS1) is developed and presented. It can efficiently obtain the cross-sections that are orthogonal to the tunnel in a dynamic way, and the control measurements that depend on design data are eliminated. By using odometers to locate the cross-sections and correcting the data based on longitudinal joints of tunnel segment lining, the cost of the system has been significantly reduced, and the interval between adjacent cross-sections can reach 1-2 cm when pushed to collect data at a normal walking speed. Meanwhile, the relative deformation of tunnel can be analyzed by selecting cross-sections from original data. Through the measurement of the actual tunnel, the applicability of the system for tunnel deformation detection is verified, and the system is shown to be 15 times more efficient than that of the total station. The simulation experiment of the tunnel deformation indicates that the measurement accuracy of TS1 for cross-sections is 1.1 mm. Compared with the traditional method, TS1 improves the efficiency as well as increases the density of the obtained points.
Unmet Needs of Families of School-Aged Children with an Autism Spectrum Disorder
ERIC Educational Resources Information Center
Brown, Hilary K.; Ouellette-Kuntz, Helene; Hunter, Duncan; Kelley, Elizabeth; Cobigo, Virginie
2012-01-01
Background: To aid decision making regarding the allocation of limited resources, information is needed on the perceived unmet needs of parents of school-aged children with an autism spectrum disorder. Materials and Methods: A cross-sectional survey was conducted of 101 Canadian families of school-aged children with an autism spectrum disorder.…
A probabilistic methodology for radar cross section prediction in conceptual aircraft design
NASA Astrophysics Data System (ADS)
Hines, Nathan Robert
System effectiveness has increasingly become the prime metric for the evaluation of military aircraft. As such, it is the decision maker's/designer's goal to maximize system effectiveness. Industry and government research documents indicate that all future military aircraft will incorporate signature reduction as an attempt to improve system effectiveness and reduce the cost of attrition. Today's operating environments demand low observable aircraft which are able to reliably take out valuable, time critical targets. Thus it is desirable to be able to design vehicles that are balanced for increased effectiveness. Previous studies have shown that shaping of the vehicle is one of the most important contributors to radar cross section, a measure of radar signature, and must be considered from the very beginning of the design process. Radar cross section estimation should be incorporated into conceptual design to develop more capable systems. This research strives to meet these needs by developing a conceptual design tool that predicts radar cross section for parametric geometries. This tool predicts the absolute radar cross section of the vehicle as well as the impact of geometry changes, allowing for the simultaneous tradeoff of the aerodynamic, performance, and cost characteristics of the vehicle with the radar cross section. Furthermore, this tool can be linked to a campaign theater analysis code to demonstrate the changes in system and system of system effectiveness due to changes in aircraft geometry. A general methodology was developed and implemented and sample computer codes applied to prototype the proposed process. Studies utilizing this radar cross section tool were subsequently performed to demonstrate the capabilities of this method and show the impact that various inputs have on the outputs of these models. The F/A-18 aircraft configuration was chosen as a case study vehicle to perform a design space exercise and to investigate the relative impact of shaping parameters on radar cross section. Finally, two unique low observable configurations were analyzed to examine the impact of shaping for stealthiness.
NASA Astrophysics Data System (ADS)
Tel, E.; Durgu, C.; Aydın, A.; Bölükdemir, M. H.; Kaplan, A.; Okuducu, Ş.
2009-12-01
In the next century the world will face the need for new energy sources. Nuclear fusion can be one of the most attractive sources of energy from the viewpoint of safety and minimal environmental impact. Fusion will not produce CO2 or SO2 and thus will not contribute to global warming or acid rain. Achieving acceptable performance for a fusion power system in the areas of economics, safety and environmental acceptability, is critically dependent on performance of the blanket and diverter systems which are the primary heat recovery, plasma purification, and tritium breeding systems. Tritium self-sufficiency must be maintained for a commercial power plant. The hybrid reactor is a combination of the fusion and fission processes. For self-sustaining (D-T) fusion driver tritium breeding ratio should be greater than 1.05. So working out the systematics of ( n, t) reaction cross-sections are of great importance for the definition of the excitation function character for the given reaction taking place on various nuclei at energies up to 20 MeV. In this study, we have calculated non-elastic cross-sections by using optical model for ( n, t) reactions at 14-15 MeV energy. We have investigated the excitation function character and reaction Q-values depending on the asymmetry term effect for the ( n, t) reaction cross-sections. We have obtained new coefficients for the ( n, t) reaction cross-sections. We have suggested semi-empirical formulas including optical model nonelastic effects by fitting two parameters for the ( n, t) reaction cross-sections at 14-15 MeV. We have discussed the odd-even effect and the pairing effect considering binding energy systematic of the nuclear shell model for the new experimental data and new cross-sections formulas ( n, t) reactions developed by Tel et al. We have determined a different parameter groups by the classification of nuclei into even-even, even-odd and odd-even for ( n, t) reactions cross-sections. The obtained cross-section formulas with new coefficients have been discussed and compared with the available experimental data.
Elastic and inelastic neutron scattering cross sections for fission reactor applications
NASA Astrophysics Data System (ADS)
Hicks, S. F.; Chakraborty, A.; Combs, B.; Crider, B. P.; Downes, L.; Girgis, J.; Kersting, L. J.; Kumar, A.; Lueck, C. J.; McDonough, P. J.; McEllistrem, M. T.; Peters, E. E.; Prados-Estevz, F. M.; Schniederjan, J.; Sidwell, L.; Sigillito, A. J.; Vanhoy, J. R.; Watts, D.; Yates, S. W.
2013-04-01
Nuclear data important for the design and development of the next generation of light-water reactors and future fast reactors include neutron elastic and inelastic scattering cross sections on important structural materials, such as Fe, and on coolant materials, such as Na. These reaction probabilities are needed since neutron reactions impact fuel performance during irradiations and the overall efficiency of reactors. While neutron scattering cross sections from these materials are available for certain incident neutron energies, the fast neutron region, particularly above 2 MeV, has large gaps for which no measurements exist, or the existing uncertainties are large. Measurements have been made at the University of Kentucky Accelerator Laboratory to measure neutron scattering cross sections on both Fe and Na in the region where these gaps occur and to reduce the uncertainties on scattering from the ground state and first excited state of these nuclei. Results from measurements on Fe at incident neutron energies between 2 and 4 MeV will be presented and comparisons will be made to model calculations available from data evaluators.
NASA Technical Reports Server (NTRS)
Frederick, J. E.; Blake, A. J.; Freeman, D. E.; Nicholls, R. W.; Ogawa, T.; Simon, P. C.
1983-01-01
The information presently available on the absorption cross sections of O2 and O3 with attention to the application of these data in middle atmospheric science is reviewed. The cross sections values reported by different groups are intercompared in tabular form where feasible, and specific values are recommended when there is a basis for preferring a particular set of results over other available data. When no such basis exists, the differences among published cross sections then serve to indicate a range of uncertainty. In these cases the need for additional work is indicated. Specific topics addressed are the absorption of molecular oxygen at Lyman alpha, in the Schumann-Runge continuum, in the Schumann-Runge bands, and in the Herzberg continuum. For ozone, the Hartley and Huggins bands are considered.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sartori, E.; Roussin, R.W.
This paper presents a brief review of computer codes concerned with checking, plotting, processing and using of covariances of neutron cross-section data. It concentrates on those available from the computer code information centers of the United States and the OECD/Nuclear Energy Agency. Emphasis will be placed also on codes using covariances for specific applications such as uncertainty analysis, data adjustment and data consistency analysis. Recent evaluations contain neutron cross section covariance information for all isotopes of major importance for technological applications of nuclear energy. It is therefore important that the available software tools needed for taking advantage of this informationmore » are widely known as hey permit the determination of better safety margins and allow the optimization of more economic, I designs of nuclear energy systems.« less
Searches for New Physics Using High Mass Dimuons at the CDF II Experiment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Karagoz Unel, Muge
2004-12-01
This work describes the measurement of inclusive jets cross section in the D0 experiment. This cross section is computed as a function of jet transverse momentum, in several rapidity intervals. This quantity is sensitive to the proton structure and is crucial for the determination of parton distribution functions (PDF), essentially for the gluon at high proton momentum fraction. The measurement presented here gives the first values obtained for Tevatron Run II for the cross section in several rapidity intervals, for an integrated luminosity of 143 pb -1. The results are in agreement, within the uncertainties, with theoretical Standard Model predictions,more » showing no evidence for new physics. This work points out the aspects of the detector which need better understanding to reach Run I precision and to constrain the PDFs.« less
NASA Astrophysics Data System (ADS)
Serdyuchenko, Anna; Gorshelev, Victor; Chehade, Wissam; Weber, Mark; Burrows, John P.
We report on the work devoted to the up-to-date measurements of the ozone absorption cross-sections. The main goal of the project is to produce a consolidated and consistent set of high resolution cross-sections for satellite spectrometers series that allows a derivation of the harmonized long term data set. The generation of long-term datasets of atmospheric trace gases is a major need and prerequisite for climate and air quality related studies. At present there are three atmospheric chemistry instruments (GOME1, SCIAMACHY and GOME2) in operation and two more spectrometers (GOME2) to be launched five years apart in the next decade resulting in a time series covering two or more decades of ozone observations. Information from different sensors has to be com-bined for a consistent long-term data record, since the lifetime of individual satellite missions is limited. The harmonization of cross-sections is carried out by combination of new experimental work with re-evaluation of the existing cross-sections data. New laboratory measurements of ozone cross-section are underway that will improve a) absolute scaling of cross-sections, b) temper-ature dependence of cross-sections (using very low temperatures starting at 190 K and higher sampling of temperatures up to room temperature) and c) improved wavelength calibration. We take advantage of a Fourier transform spectrometer (visible, near IR) and Echelle spectropho-tometer (UV, visible) to extend the dynamic range of the system (covering several orders of magnitude in cross-sections from UV up to the near IR). We plan to cover the spectral range 220 -1000 nm at a spectral resolution of 0.02 nm in UV/VIS with absolute intensity accuracy of at least 2%, and wavelength accuracy better than 0.001 nm in the temperature range 193-293 K in 10 K steps. A lot of attention is paid to the accuracy of determining the temperature of the ozone flow and new methods for absolute calibration of relative spectra. This work is in progress. Based on the results of the work, it is expected that the ozone data quality and time series will improve significantly as required for climate, air quality, and strato-spheric ozone trend studies. Updated ozone cross-sections will be available for reprocessing with satellite spectrometers and to the scientific community as well.
NASA Technical Reports Server (NTRS)
Huestis, David L.
2006-01-01
We propose to establish a long-term program of critical evaluation by domain experts of the rates and cross sections for atomic and molecular processes that are needed for understanding and modeling the atmospheres in the solar system. We envision data products resembling those of the JPL/NASA Panel for Data Evaluation and the similar efforts of the international combustion modeling community funded by US DoE and its European counterpart.
Hard matching for boosted tops at two loops
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoang, Andre H.; Pathak, Aditya; Pietrulewicz, Piotr
2015-12-10
Here, cross sections for top quarks provide very interesting physics opportunities, being both sensitive to new physics and also perturbatively tractable due to the large top quark mass. Rigorous factorization theorems for top cross sections can be derived in several kinematic scenarios, including the boosted regime in the peak region that we consider here. In the context of the corresponding factorization theorem for e +e – collisions we extract the last missing ingredient that is needed to evaluate the cross section differential in the jet-mass at two-loop order, namely the matching coefficient at the scale μ≃m t. Our extraction alsomore » yields the final ingredients needed to carry out logarithmic re-summation at next-to-next-to-leading logarithmic order (or N 3LL if we ignore the missing 4-loop cusp anomalous dimension). This coefficient exhibits an amplitude level rapidity logarithm starting at O(α 2 s) due to virtual top quark loops, which we treat using rapidity renormalization group (RG) evolution. Interestingly, this rapidity RG evolution appears in the matching coefficient between two effective theories around the heavy quark mass scale μ ≃ m t.« less
ERIC Educational Resources Information Center
Breslin, Gavin; Shannon, Stephen; Fitzpatrick, Ben; Hanna, Donncha; Belton, Sarahjane; Brennan, Deirdre
2017-01-01
Need-supportive environments have been shown to predict children's physical activity levels, and in a few cases to well-being. Grounded in self-determination theory (SDT), this cross-sectional study aimed to determine the influence of psychological need (competence and social relatedness) satisfaction on physical activity levels and well-being in…
Spinal Cord Gray Matter Atrophy in Amyotrophic Lateral Sclerosis.
Paquin, M-Ê; El Mendili, M M; Gros, C; Dupont, S M; Cohen-Adad, J; Pradat, P-F
2018-01-01
There is an emerging need for biomarkers to better categorize clinical phenotypes and predict progression in amyotrophic lateral sclerosis. This study aimed to quantify cervical spinal gray matter atrophy in amyotrophic lateral sclerosis and investigate its association with clinical disability at baseline and after 1 year. Twenty-nine patients with amyotrophic lateral sclerosis and 22 healthy controls were scanned with 3T MR imaging. Standard functional scale was recorded at the time of MR imaging and after 1 year. MR imaging data were processed automatically to measure the spinal cord, gray matter, and white matter cross-sectional areas. A statistical analysis assessed the difference in cross-sectional areas between patients with amyotrophic lateral sclerosis and controls, correlations between spinal cord and gray matter atrophy to clinical disability at baseline and at 1 year, and prediction of clinical disability at 1 year. Gray matter atrophy was more sensitive to discriminate patients with amyotrophic lateral sclerosis from controls ( P = .004) compared with spinal cord atrophy ( P = .02). Gray matter and spinal cord cross-sectional areas showed good correlations with clinical scores at baseline ( R = 0.56 for gray matter and R = 0.55 for spinal cord; P < .01). Prediction at 1 year with clinical scores ( R 2 = 0.54) was improved when including a combination of gray matter and white matter cross-sectional areas ( R 2 = 0.74). Although improvements over spinal cord cross-sectional areas were modest, this study suggests the potential use of gray matter cross-sectional areas as an MR imaging structural biomarker to monitor the evolution of amyotrophic lateral sclerosis. © 2018 by American Journal of Neuroradiology.
Disability and the impact of need for periodontal care on quality of life: A cross-sectional study
AlAgl, Adel
2017-01-01
Objective The need for periodontal care may negatively impact daily life. We compared the need for periodontal care and its impact on daily life between disabled and healthy adults in the Eastern Province, Saudi Arabia. Methods In this cross-sectional study of 819 adults, a questionnaire was used to assess personal background factors; the impact of periodontitis on pain, avoiding foods, embarrassment, sleeplessness, work absence, and discontinuing daily activities; and risk factors (smoking, diabetes, toothbrushing, insurance, professional tooth cleaning, and dental visits). The outcome was clinically assessed need for periodontal care impacting daily life. The relationship between the outcome and risk factors adjusted for personal background and disability was assessed using ordinal regression. Results Healthy and disabled persons had a high need for periodontal care (66.8%). Current smokers had a higher likelihood and health-insured persons had a lower likelihood of need for periodontal care impacting daily life regardless of whether disability was considered. Conclusions Most adults needed periodontal care, and disabled persons experienced a greater impact on life. Current smokers and uninsured persons were more likely to need periodontal care impacting daily life. Our findings are important for the prevention of periodontitis through tobacco cessation and extending insurance coverage. PMID:28635358
Dissociative Recombination without a Curve Crossing
NASA Technical Reports Server (NTRS)
Guberman, Steven L.
1994-01-01
Ab initio calculations show that a curve crossing is not always needed for a high dissociative- recombination cross section. For HeH(+), in which no neutral states cross the ion potential curve, dissociative recombination is driven by the nuclear kinetic-energy operator on adiabatic potential curves. The kinetic-energy derivative operator allows for capture into repulsive curves that are outside of the classical turning points for the nuclear motion. The dominant dissociative route is the C (2)Sigma(+) state leading to H(n = 2) atoms. An analogous mechanism is proposed for the dissociative recombination of H3(+).
Direct and compound reactions induced by unstable helium beams near the Coulomb barrier
DOE Office of Scientific and Technical Information (OSTI.GOV)
Navin, A.; Tripathi, V.; Chatterjee, A.
2004-10-01
Reactions induced by radioactive {sup 6,8}He beams from the SPIRAL facility were studied on {sup 63,65}Cu and {sup 188,190,192}Os targets and compared to reactions with the stable {sup 4}He projectiles from the Mumbai Pelletron. Partial residue cross sections for fusion and neutron transfer obtained from the measured intensities of characteristic in-beam {gamma} rays for the {sup 6}He+{sup 63,65}Cu systems are presented. Coincidence measurements of heavy reaction products, identified by their characteristic {gamma} rays, with projectilelike charged particles, provide direct evidence for a large transfer cross section with Borromean nuclei {sup 6}He at 19.5 and 30 MeV and {sup 8}He atmore » 27 MeV. Reaction cross sections were also obtained from measured elastic angular distributions for {sup 6,8}He+Cu systems. Cross sections for fusion and direct reactions with {sup 4,6}He beams on heavier targets of {sup 188,192}Os at 30 MeV are also presented. The present work underlines the need to distinguish between various reaction mechanisms leading to the same products before drawing conclusions about the effect of weak binding on the fusion process. The feasibility of extracting small cross sections from inclusive in-beam {gamma}-ray measurements for reaction studies near the Coulomb barrier with low intensity isotope separation on-line beams is highlighted.« less
Rowan, Elisabeth L.
2006-01-01
Introduction: Three regional-scale, cross sectional (2-D) burial and thermal history models are presented for the central Appalachian basin based on the detailed geologic cross sections of Ryder and others (2004), Crangle and others (2005), and Ryder, R.T., written communication. The models integrate the available thermal and geologic information to constrain the burial, uplift, and erosion history of the region. The models are restricted to the relatively undeformed part of the basin and extend from the Rome trough in West Virginia and Pennsylvania northwestward to the Findlay arch in Ohio. This study expands the scope of previous work by Rowan and others (2004) which presented a preliminary burial/thermal history model for a cross section (E-E') through West Virginia and Ohio. In the current study, the burial/thermal history model for E-E' is revised, and integrated with results of two additional cross sectional models (D-D' and C-C'). The burial/thermal history models provide calculated thermal maturity (Ro%) values for the entire stratigraphic sequence, including hydrocarbon source rocks, along each of the three cross sections. In contrast, the Ro and conodont CAI data available in the literature are sparse and limited to specific stratigraphic intervals. The burial/thermal history models also provide the regional temperature and pressure framework that is needed to model hydrocarbon migration.
A new beam theory using first-order warping functions
NASA Technical Reports Server (NTRS)
Ie, C. A.; Kosmatka, J. B.
1990-01-01
Due to a certain type of loading and geometrical boundary conditions, each beam will respond differently depending on its geometrical form of the cross section and its material definition. As an example, consider an isotropic rectangular beam under pure bending. Plane sections perpendicular to the longitudinal axis of the beam will remain plane and perpendicular to the deformed axis after deformation. However, due to the Poisson effect, particles in the planes will move relative to each other resulting in a form of anticlastic deformation. In other words, even in pure bending of an isotropic beam, each cross section will deform in the plane. If the material of the beam above is replaced by a generally anisotropic material, then the cross sections will not only deform in the plane, but also out of plane. Hence, in general, both in-plane deformation and out-of-plane warping will exist and depend on the geometrical form and material definition of the cross sections and also on the loadings. For the purpose of explanation, an analogy is made. The geometrical forms of the bodies of each individual are unique. Hence, different sizes of clothes are needed. Finding the sizes of clothes for individuals is like determining the warping functions in beams. A new beam theory using first-order warping functions is introduced. Numerical examples will be presented for an isotropic beam with rectangular cross section. The theory can be extended for composite beams.
Integral cross sections for electron impact excitation of electronic states of N2
NASA Astrophysics Data System (ADS)
Campbell, L.; Brunger, M. J.; Nolan, A. M.; Kelly, L. J.; Wedding, A. B.; Harrison, J.; Teubner, P. J. O.; Cartwright, D. C.; McLaughlin, B.
2001-04-01
We report integral cross sections (ICSs) for electron impact excitation of the A 3Σ+u, B 3Πg, W 3Δu, B' 3Σ-u, a' 1Σ-u, a 1Πg, ω1Δu, C 3Πu, E 3Σ+g and a'' 1Σ+g electronic states of N2. The present data, for each state, were derived at five incident electron energies in the range 15-50 eV, from the earlier crossed-beam differential cross section (DCS) measurements of our group. This was facilitated by using a molecular phase shift analysis technique to extrapolate the measured DCSs to 0° and 180°, before performing the integration. A comprehensive comparison of the present ICSs with the results of earlier experimental studies, both crossed beam and electron swarm, and theoretical calculations is provided. This comparison clearly indicates that some of the previous estimates for these excited electronic-state cross sections need to be reassessed. In addition, we have used the present ICSs in a Monte Carlo simulation for modelling the behaviour of an electron swarm in the bulk of a low current N2 discharge. The macroscopic transport parameters determined from this simulation are compared against those measured from independent swarm-based experiments and the self-consistency of our ICSs evaluated.
Ayazi, Touraj; Swartz, Leslie; Eide, Arne H; Lien, Lars; Hauff, Edvard
2015-08-19
To examine the current perceived needs of the general population in a war-affected setting, and to study the influence of perceived needs on the participants' mental health status and functional impairment across genders. A cross-sectional community survey (n=464) was conducted in war-affected South Sudan. Three regression models were analysed. Perceived needs were assessed with the Humanitarian Emergency Settings Perceived Needs Scale. Psychological distress was measured with the General Health Questionnaire and level of functioning by the Short Form Health Survey (SF-12). The most frequently expressed needs were related to drinking water, alcohol and drug use in the community and access to sanitation facilities. No gender differences were found regarding the level of perceived needs or the number of traumatic events. Higher level of perceived needs significantly predicted psychological distress and lower level of functioning even when numbers of experienced trauma events were taken into account. The associations of higher level of needs and trauma experiences, on the one hand, and negative health outcomes on the other, necessitate a greater integration of interventions directed towards the population's perceived needs and mental health, particularly for those who have been exposed to trauma. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Kirane, Akhilesh G; Gaikwad, Nandkishor B; Bhingare, Prashant E; Mule, Vidya D
2015-12-01
Better diagnosis and early referral due to increased health care coverage have increased the cesarean deliveries at tertiary-care hospitals of India. Improvements in the health care system raise many concerns and need of cross-checking system in place to counter the problems pertaining to patient education and participation of patient. While most of the cesarean sections are done in good faith for the patient, it does not escape the purview of consumer awareness and protection. This cross-sectional study was undertaken at a tertiary level government institution to understand the level of awareness of 220 patients regarding the various aspects of cesarean delivery which are essential for women to know before giving an informed consent. 71 % of the women had knowledge about the indication and need to do cesarean delivery. Of these, only one-third (25 % of total women) were properly explained about procedure and complications. Other demographic and social characteristics were also evaluated. While the health care schemes have had their improved results, the onus lies upon the caregivers to improve and maintain the quality of health care in these tertiary-care government hospitals in proportion to the increase in patient load. The results of this study highlight the need for proper counseling of patients regarding complications of cesarean section. The fact that only 25 % of total cases were explained proper procedure and complication as opposed to 71 % of patients having proper knowledge about the indication of cesarean section points out the lack of information in seemingly "informed" consent. To bring about awareness about the risks and complications of cesarean section, there is a need that patients be counseled during the antenatal visits, specifically when patients visit near term for antenatal check up.
DIFFERENTIAL CROSS SECTION ANALYSIS IN KAON PHOTOPRODUCTION USING ASSOCIATED LEGENDRE POLYNOMIALS
DOE Office of Scientific and Technical Information (OSTI.GOV)
P. T. P. HUTAURUK, D. G. IRELAND, G. ROSNER
2009-04-01
Angular distributions of differential cross sections from the latest CLAS data sets,6 for the reaction γ + p→K+ + Λ have been analyzed using associated Legendre polynomials. This analysis is based upon theoretical calculations in Ref. 1 where all sixteen observables in kaon photoproduction can be classified into four Legendre classes. Each observable can be described by an expansion of associated Legendre polynomial functions. One of the questions to be addressed is how many associated Legendre polynomials are required to describe the data. In this preliminary analysis, we used data models with different numbers of associated Legendre polynomials. We thenmore » compared these models by calculating posterior probabilities of the models. We found that the CLAS data set needs no more than four associated Legendre polynomials to describe the differential cross section data. In addition, we also show the extracted coefficients of the best model.« less
NASA Astrophysics Data System (ADS)
Dodig, H.
2017-11-01
This contribution presents the boundary integral formulation for numerical computation of time-harmonic radar cross section for 3D targets. Method relies on hybrid edge element BEM/FEM to compute near field edge element coefficients that are associated with near electric and magnetic fields at the boundary of the computational domain. Special boundary integral formulation is presented that computes radar cross section directly from these edge element coefficients. Consequently, there is no need for near-to-far field transformation (NTFFT) which is common step in RCS computations. By the end of the paper it is demonstrated that the formulation yields accurate results for canonical models such as spheres, cubes, cones and pyramids. Method has demonstrated accuracy even in the case of dielectrically coated PEC sphere at interior resonance frequency which is common problem for computational electromagnetic codes.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Frederick, J.E.; Blake, A.J.; Freeman, D.E.
1983-07-01
The information presently available on the absorption cross sections of O2 and O3 with attention to the application of these data in middle atmospheric science is reviewed. The cross sections values reported by different groups are intercompared in tabular form where feasible, and specific values are recommended when there is a basis for preferring a particular set of results over other available data. When no such basis exists, the differences among published cross sections then serve to indicate a range of uncertainty. In these cases the need for additional work is indicated. Specific topics addressed are the absorption of molecularmore » oxygen at Lyman alpha, in the Schumann-Runge continuum, in the Schumann-Runge bands, and in the Herzberg continuum. For ozone, the Hartley and Huggins bands are considered.« less
Stieger, Stefan; Gumhalter, Nora; Tran, Ulrich S.; Voracek, Martin; Swami, Viren
2013-01-01
The present study utilized a repeated cross-sectional survey design to examine belief in conspiracy theories about the abduction of Natascha Kampusch. At two time points (October 2009 and October 2011), participants drawn from independent cross-sections of the Austrian population (Time Point 1, N = 281; Time Point 2, N = 277) completed a novel measure of belief in conspiracy theories concerning the abduction of Kampusch, as well as measures of general conspiracist ideation, self-esteem, paranormal and superstitious beliefs, cognitive ability, and media exposure to the Kampusch case. Results indicated that although belief in the Kampusch conspiracy theory declined between testing periods, the effect size of the difference was small. In addition, belief in the Kampusch conspiracy theory was significantly predicted by general conspiracist ideation at both time points. The need to conduct further longitudinal tests of conspiracist ideation is emphasized in conclusion. PMID:23745118
ERIC Educational Resources Information Center
Lin, Lan-Ping; Lin, Pei-Ying; Chu, Cordia M.; Lin, Jin-Ding
2011-01-01
Although many previous studies have begun to address the reproductive health needs of women with intellectual disabilities; however, the supportive behaviors of caregivers to assist their reproductive health is not well understood. Data from a cross-sectional survey of ""2009 National Survey on Reproductive Health Care Needs and Health…
Ko, Naomi Yu; Battaglia, Tracy A; Gupta-Lawrence, Rebecca; Schiller, Jessica; Gunn, Christine; Festa, Kate; Nelson, Kerrie; Flacks, JoHanna; Morton, Samantha J; Rosen, Jennifer E
2016-06-14
Social and economic conditions that affect one's ability to satisfy life's most basic needs such as lack of affordable housing, restricted access to education and employment, or inadequate income are increasingly well-documented barriers to optimal health. The burden of these challenges among vulnerable patients accessing cancer care services is unknown. We conducted a cross-sectional survey of patients presenting for ambulatory cancer care services (screening and treatment) at an urban safety-net hospital to assess socio-legal concerns (social problems related to meeting life's basic needs supported by public policy or programming and potentially remedied through legal advocacy/action). Among 104 respondents, 80 (77 %) reported concerns with one or more socio-legal needs in the past month, with a mean of 5.75 concerns per participant. The most common socio-legal concerns related to income supports, housing, and employment/education. Our findings support the need for innovations in cancer care delivery to address socio-legal concerns of a vulnerable patient population.
2013-01-01
Background Understanding children’s physical activity motivation, its antecedents and associations with behavior is important and can be advanced by using self-determination theory. However, research among youth is largely restricted to adolescents and studies of motivation within certain contexts (e.g., physical education). There are no measures of self-determination theory constructs (physical activity motivation or psychological need satisfaction) for use among children and no previous studies have tested a self-determination theory-based model of children’s physical activity motivation. The purpose of this study was to test the reliability and validity of scores derived from scales adapted to measure self-determination theory constructs among children and test a motivational model predicting accelerometer-derived physical activity. Methods Cross-sectional data from 462 children aged 7 to 11 years from 20 primary schools in Bristol, UK were analysed. Confirmatory factor analysis was used to examine the construct validity of adapted behavioral regulation and psychological need satisfaction scales. Structural equation modelling was used to test cross-sectional associations between psychological need satisfaction, motivation types and physical activity assessed by accelerometer. Results The construct validity and reliability of the motivation and psychological need satisfaction measures were supported. Structural equation modelling provided evidence for a motivational model in which psychological need satisfaction was positively associated with intrinsic and identified motivation types and intrinsic motivation was positively associated with children’s minutes in moderate-to-vigorous physical activity. Conclusions The study provides evidence for the psychometric properties of measures of motivation aligned with self-determination theory among children. Children’s motivation that is based on enjoyment and inherent satisfaction of physical activity is associated with their objectively-assessed physical activity and such motivation is positively associated with perceptions of psychological need satisfaction. These psychological factors represent potential malleable targets for interventions to increase children’s physical activity. PMID:24067078
Gambhir, Ramandeep S.; Sogi, Girish M.; Veeresha, Koratagere Lingappa; Sohi, Ramandeep K.; Randhawa, Amaninder; Kakar, Heena
2013-01-01
Aim: To assess the dental health status and treatment needs of transport workers working in Chandigarh Transport Undertaking (C.T.U.) buses, Chandigarh. Materials and Methods: A cross-sectional study was conducted on all the available C.T.U. workers at all three bus depots. The data were recorded on a modified W.H.O. format (1997). A total of 1008 subjects constituted the final sample size. Results: The mean age of the subjects was 45.3 ± 7.8 years, and 97% (978) were males. Prevalence of dental caries was 63.4% and mean DMFT was 5.02. 47.6% of subjects needed some prosthesis in the maxillary arch while 53.3% needed some prosthesis in the mandibular arch. Regarding highest CPI (Community Periodontal Index) score, 8.13% of the subjects had healthy periodontium while maximum subjects (73.2%) had a score 2 (Calculus). Conclusion: Mean DMFT (Decayed, Missing and Filled Teeth) was satisfactory. Prosthetic need of the subjects was high with only a few subjects possessing prosthesis. Advanced periodontal disease (CPI score, 4) affected small number of subjects with maximum subjects (73%) having a CPI score of 2. PMID:24082750
Analytic integration of real-virtual counterterms in NNLO jet cross sections II
NASA Astrophysics Data System (ADS)
Bolzoni, Paolo; Moch, Sven-Olaf; Somogyi, Gábor; Trócsányi, Zoltán
2009-08-01
We present analytic expressions of all integrals required to complete the explicit evaluation of the real-virtual integrated counterterms needed to define a recently proposed subtraction scheme for jet cross sections at next-to-next-to-leading order in QCD. We use the Mellin-Barnes representation of these integrals in 4 - 2epsilon dimensions to obtain the coefficients of their Laurent expansions around epsilon = 0. These coefficients are given by linear combinations of multidimensional Mellin-Barnes integrals. We compute the coefficients of such expansions in epsilon both numerically and analytically by complex integration over the Mellin-Barnes contours.
A Cross-sectional Study of Midwives' Perspectives Towards their Professional Educational Needs.
Abedian, Kobra; Charati, Jamshid Yazdani; Samadaee, Keshvar; Shahhosseini, Zohreh
2014-06-01
Midwives are one of the most important health care providers and meeting their professional educational needs can be effective in maternal and child health promotion. The aim of this study was to investigate the midwives' perspectives towards their educational needs. In this cross-sectional study which was conducted in 2012 in Sari, North of Iran, 223 midwives during a convenience sampling method expressed their educational needs. The instrument of the data collection was a self-administered 64-question researcher- made questionnaire about the participants' educational needs in 10 fields related to midwifery profession. The mean age and employment record of the participants were 33.87±10.49 and 10.09±8.14 years respectively, and the majority (65.02%) of them was employed in the health care centers. Findings showed that the highest score of midwives' educational need was related to need to education about labor and delivery care (75.14±21.13%) which was followed by the need to education about pre marriage counseling (74.04±19.95%) and pre conception counseling (71.33±21.89%). Owing to the emergence of new dimensions of tasks in midwifery practice and due to developing some changes in the educational needs of midwives, it's necessary to implement an updated educational package in order to deliver the recommended standards of care and to increase midwives' participation in continuing education programs.
Neutrino-nucleus cross sections for oscillation experiments
NASA Astrophysics Data System (ADS)
Katori, Teppei; Martini, Marco
2018-01-01
Neutrino oscillations physics is entering an era of high precision. In this context, accelerator-based neutrino experiments need a reduction in systematic errors to the level of a few percent. Today, one of the most important sources of systematic errors are neutrino-nucleus cross sections which, in the energy region of hundreds of MeV to a few GeV, are known to a precision not exceeding 20%. In this article we review the present experimental and theoretical knowledge of neutrino-nucleus interaction physics. After introducing neutrino-oscillation physics and accelerator-based neutrino experiments, we give an overview of general aspects of neutrino-nucleus cross sections, from both the theoretical and experimental point of view. Then, we focus on these cross sections in different reaction channels. We start with the quasi-elastic and quasi-elastic-like cross section, placing a special emphasis on the multinucleon emission channel, which has attracted a lot of attention in the last few years. We review the main aspects of the different microscopic models for this channel by discussing analogies and the differences among them. The discussion is always driven by a comparison with the experimental data. We then consider the one-pion production channel where agreement between data and theory remains highly unsatisfactory. We describe how to interpret pion data, and then analyze, in particular, the puzzle related to the difficulty of theoretical models and Monte Carlo to simultaneously describe MiniBooNE and MINERvA experimental results. Inclusive cross sections are also discussed, as well as the comparison between the {ν }μ and {ν }e cross sections, relevant for the charge-conjugation-parity violation experiments. The impact of nuclear effects on the reconstruction of neutrino energy and on the determination of the neutrino-oscillation parameters is also reviewed. Finally, we look to the future by discussing projects and efforts in relation to future detectors, beams, and analysis.
NASA Astrophysics Data System (ADS)
Monfared, Shabnam; Buttler, William; Schauer, Martin; Lalone, Brandon; Pack, Cora; Stevens, Gerald; Stone, Joseph; Special Technologies Laboratory Collaboration; Los Alamos National Laboratory Team
2014-03-01
Los Alamos National Laboratory is actively engaged in the study of material failure physics to support the hydrodynamic models development, where an important failure mechanism of explosively shocked metals causes mass ejection from the backside of a shocked surface with surface perturbations. Ejecta models are in development for this situation. Our past work has clearly shown that the total ejected mass and mass-velocity distribution sensitively link to the wavelength and amplitude of these perturbations. While we have had success developing ejecta mass and mass-velocity models, we need to better understand the size and size-velocity distributions of the ejected mass. To support size measurements we have developed a dynamic Mie scattering diagnostic based on a CW laser that permits measurement of the forward attenuation cross-section combined with a dynamic mass-density and mass-velocity distribution, as well as a measurement of the forward scattering cross-section at 12 angles (5- 32.5 degrees) in increments of 2.5 degrees. We compare size distribution followed from Beers law with attenuation cross-section and mass measurement to the dynamic size distribution determined from scattering cross-section alone. We report results from our first quality experiments.
Note on measuring electronic stopping of slow ions
NASA Astrophysics Data System (ADS)
Sigmund, P.; Schinner, A.
2017-11-01
Extracting stopping cross sections from energy-loss measurements requires careful consideration of the experimental geometry. Standard procedures for separating nuclear from electronic stopping treat electronic energy loss as a friction force, ignoring its dependence on impact parameter. In the present study we find that incorporating this dependence has a major effect on measured stopping cross sections, in particular for light ions at low beam energies. Calculations have been made for transmission geometry, nuclear interactions being quantified by Bohr-Williams theory of multiple scattering on the basis of a Thomas-Fermi-Molière potential, whereas electronic interactions are characterized by Firsov theory or PASS code. Differences between the full and the restricted stopping cross section depend on target thickness and opening angle of the detector and need to be taken into account in comparisons with theory as well as in applications of stopping data. It follows that the reciprocity principle can be violated when checked on restricted instead of full electronic stopping cross sections. Finally, we assert that a seeming gas-solid difference in stopping of low-energy ions is actually a metal-insulator difference. In comparisons with experimental results we mostly consider proton data, where nuclear stopping is only a minor perturbation.
NASA Astrophysics Data System (ADS)
Divay, C.; Colin, J.; Cussol, D.; Finck, Ch.; Karakaya, Y.; Labalme, M.; Rousseau, M.; Salvador, S.; Vanstalle, M.
2017-04-01
During a carbon therapy treatment, the beam undergoes inelastic nuclear reactions leading to the production of secondary fragments. These nuclear interactions tend to delocate a part of the dose into healthy tissues and create a mixed radiation field. In order to accurately estimate the dose deposited into the tissues, the production rate of these fragments all along the beam path have to be taken into account. But the double differential carbon fragmentation cross sections are not well known in the energy range needed for a treatment (up to 400 MeV/nucleon). Therefore, a series of experiments aiming to measure the double differential fragmentation cross sections of carbon on thin targets of medical interest has been started by our collaboration. In March 2015 we performed an experiment to study the fragmentation of a 50 MeV/nucleon 12C beam on thin targets at GANIL. During this experiment, energy and angular cross-section distributions on H, C, O, Al, and natTi have been measured. The experimental set-up will be detailed as well as the systematic error study and all the experimental results will be presented.
First measurement of coherent ϕ -meson photoproduction from 4He near threshold
NASA Astrophysics Data System (ADS)
Hiraiwa, T.; Yosoi, M.; Niiyama, M.; Morino, Y.; Nakatsugawa, Y.; Sumihama, M.; Ahn, D. S.; Ahn, J. K.; Chang, W. C.; Chen, J. Y.; Daté, S.; Fujimura, H.; Fukui, S.; Hicks, K.; Hotta, T.; Hwang, S. H.; Ishikawa, T.; Kato, Y.; Kawai, H.; Kohri, H.; Kon, Y.; Lin, P. J.; Maeda, Y.; Miyabe, M.; Mizutani, K.; Muramatsu, N.; Nakano, T.; Nozawa, Y.; Ohashi, Y.; Ohta, T.; Oka, M.; Rangacharyulu, C.; Ryu, S. Y.; Saito, T.; Sawada, T.; Shimizu, H.; Strokovsky, E. A.; Sugaya, Y.; Suzuki, K.; Tokiyasu, A. O.; Tomioka, T.; Tsunemi, T.; Uchida, M.; Yorita, T.; LEPS Collaboration
2018-03-01
The differential cross sections and decay angular distributions for coherent ϕ -meson photoproduction from helium-4 are measured for the first time at forward angles with linearly polarized photons in the energy range Eγ=1.685 -2.385 GeV . Thanks to the target with spin-parity JP=0+ , unnatural-parity exchanges are absent, and thus natural-parity exchanges can be investigated clearly. The decay asymmetry with respect to photon polarization is shown to be very close to the maximal value. This ensures the strong dominance (>94 %) of natural-parity exchanges in this reaction. To evaluate the contribution from natural-parity exchanges to the forward cross section (θ =0∘ ) for the γ p →ϕ p reaction near threshold, the energy dependence of the forward cross section (θ =0∘ ) for the γ 4He →ϕ 4He reaction is analyzed. The comparison to γ p →ϕ p data suggests that enhancement of the forward cross section arising from natural-parity exchanges and/or destructive interference between natural-parity and unnatural-parity exchanges is needed in the γ p →ϕ p reaction near threshold.
State-resolved Photodissociation and Radiative Association Data for the Molecular Hydrogen Ion
NASA Astrophysics Data System (ADS)
Zammit, Mark C.; Savage, Jeremy S.; Colgan, James; Fursa, Dmitry V.; Kilcrease, David P.; Bray, Igor; Fontes, Christopher J.; Hakel, Peter; Timmermans, Eddy
2017-12-01
We present state-resolved (electronic, vibrational, and rotational) cross sections and rate coefficients for the photodissociation (PD) of {{{H}}}2+ and radiative association (RA) of H–H+. We developed a fully quantum mechanical approach within the nonrelativistic Born–Oppenheimer approximation to describe {{{H}}}2+ and calculate the data for transitions between the ground electronic state 1s{σ }g and the 2p{σ }u, 2p{π }u, 3p{σ }u, 3p{π }u, 4p{σ }u, 4f{σ }u, 4f{π }u, and 4p{π }u electronic states (i.e., up to {{{H}}}2+ n = 4). Tables of the dipole-matrix elements and energies needed to calculate state-resolved cross sections and rate coefficients will be made publicly available. These data could be important in astrophysical models when dealing with photon wavelengths (or radiation temperature distributions that are weighted toward such wavelengths) around 100 nm. For example, at these wavelengths and a material temperature of 8400 K, the LTE-averaged PD cross section via the (second electronically excited) 2p{π }u state is over three times larger than the PD cross section via the (first electronically excited) 2p{σ }u state.
Isotope production and target preparation for nuclear astrophysics data
NASA Astrophysics Data System (ADS)
Schumann, Dorothea; Dressler, Rugard; Maugeri, Emilio Andrea; Heinitz, Stephan
2017-09-01
Targets are in many cases an indispensable ingredient for successful experiments aimed to produce nuclear data. With the recently observed shift to study nuclear reactions on radioactive targets, this task can become extremely challenging. Concerted actions of a certain number of laboratories able to produce isotopes and manufacture radioactive targets are urgently needed. We present here some examples of successful isotope and target production at PSI, in particular the production of 60Fe samples used for half-life measurements and neutron capture cross section experiments, the chemical processing and fabrication of lanthanide targets for capture cross section experiments at n_TOF (European Organization for Nuclear Research (CERN), Switzerland) as well as the recently performed manufacturing of highly-radioactive 7Be targets for the measurement of the 7Be(n,α)4He cross section in the energy range of interest for the Big-Bang nucleosynthesis contributing to the solving of the cosmological Li-problem. The two future projects: "Determination of the half-life and experiments on neutron capture cross sections of 53Mn" and "32Si - a new chronometer for nuclear dating" are briefly described. Moreover, we propose to work on the establishment of a dedicated network on isotope and target producing laboratories.
Origami tubes with reconfigurable polygonal cross-sections.
Filipov, E T; Paulino, G H; Tachi, T
2016-01-01
Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings.
Origami tubes with reconfigurable polygonal cross-sections
Filipov, E. T.; Paulino, G. H.; Tachi, T.
2016-01-01
Thin sheets can be assembled into origami tubes to create a variety of deployable, reconfigurable and mechanistically unique three-dimensional structures. We introduce and explore origami tubes with polygonal, translational symmetric cross-sections that can reconfigure into numerous geometries. The tubular structures satisfy the mathematical definitions for flat and rigid foldability, meaning that they can fully unfold from a flattened state with deformations occurring only at the fold lines. The tubes do not need to be straight and can be constructed to follow a non-linear curved line when deployed. The cross-section and kinematics of the tubular structures can be reprogrammed by changing the direction of folding at some folds. We discuss the variety of tubular structures that can be conceived and we show limitations that govern the geometric design. We quantify the global stiffness of the origami tubes through eigenvalue and structural analyses and highlight the mechanical characteristics of these systems. The two-scale nature of this work indicates that, from a local viewpoint, the cross-sections of the polygonal tubes are reconfigurable while, from a global viewpoint, deployable tubes of desired shapes are achieved. This class of tubes has potential applications ranging from pipes and micro-robotics to deployable architecture in buildings. PMID:26997894
Converting point-wise nuclear cross sections to pole representation using regularized vector fitting
NASA Astrophysics Data System (ADS)
Peng, Xingjie; Ducru, Pablo; Liu, Shichang; Forget, Benoit; Liang, Jingang; Smith, Kord
2018-03-01
Direct Doppler broadening of nuclear cross sections in Monte Carlo codes has been widely sought for coupled reactor simulations. One recent approach proposed analytical broadening using a pole representation of the commonly used resonance models and the introduction of a local windowing scheme to improve performance (Hwang, 1987; Forget et al., 2014; Josey et al., 2015, 2016). This pole representation has been achieved in the past by converting resonance parameters in the evaluation nuclear data library into poles and residues. However, cross sections of some isotopes are only provided as point-wise data in ENDF/B-VII.1 library. To convert these isotopes to pole representation, a recent approach has been proposed using the relaxed vector fitting (RVF) algorithm (Gustavsen and Semlyen, 1999; Gustavsen, 2006; Liu et al., 2018). This approach however needs to specify ahead of time the number of poles. This article addresses this issue by adding a poles and residues filtering step to the RVF procedure. This regularized VF (ReV-Fit) algorithm is shown to efficiently converge the poles close to the physical ones, eliminating most of the superfluous poles, and thus enabling the conversion of point-wise nuclear cross sections.
Evaporation residue cross-section measurements for 48Ti-induced reactions
NASA Astrophysics Data System (ADS)
Sharma, Priya; Behera, B. R.; Mahajan, Ruchi; Thakur, Meenu; Kaur, Gurpreet; Kapoor, Kushal; Rani, Kavita; Madhavan, N.; Nath, S.; Gehlot, J.; Dubey, R.; Mazumdar, I.; Patel, S. M.; Dhibar, M.; Hosamani, M. M.; Khushboo, Kumar, Neeraj; Shamlath, A.; Mohanto, G.; Pal, Santanu
2017-09-01
Background: A significant research effort is currently aimed at understanding the synthesis of heavy elements. For this purpose, heavy ion induced fusion reactions are used and various experimental observations have indicated the influence of shell and deformation effects in the compound nucleus (CN) formation. There is a need to understand these two effects. Purpose: To investigate the effect of proton shell closure and deformation through the comparison of evaporation residue (ER) cross sections for the systems involving heavy compound nuclei around the ZCN=82 region. Methods: A systematic study of ER cross-section measurements was carried out for the 48Ti+Nd,150142 , 144Sm systems in the energy range of 140 -205 MeV . The measurement has been performed using the gas-filled mode of the hybrid recoil mass analyzer present at the Inter University Accelerator Centre (IUAC), New Delhi. Theoretical calculations based on a statistical model were carried out incorporating an adjustable barrier scaling factor to fit the experimental ER cross section. Coupled-channel calculations were also performed using the ccfull code to obtain the spin distribution of the CN, which was used as an input in the calculations. Results: Experimental ER cross sections for 48Ti+Nd,150142 were found to be considerably smaller than the statistical model predictions whereas experimental and statistical model predictions for 48Ti+144Sm were of comparable magnitudes. Conclusion: Though comparison of experimental ER cross sections with statistical model predictions indicate considerable non-compound-nuclear processes for 48Ti+Nd,150142 reactions, no such evidence is found for the 48Ti+144Sm system. Further investigations are required to understand the difference in fusion probabilities of 48Ti+142Nd and 48Ti+144Sm systems.
The electron-furfural scattering dynamics for 63 energetically open electronic states
NASA Astrophysics Data System (ADS)
da Costa, Romarly F.; do N. Varella, Márcio T.; Bettega, Márcio H. F.; Neves, Rafael F. C.; Lopes, Maria Cristina A.; Blanco, Francisco; García, Gustavo; Jones, Darryl B.; Brunger, Michael J.; Lima, Marco A. P.
2016-03-01
We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C5H4O2). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (Nopen) at either the static-exchange (Nopen ch-SE) or the static-exchange-plus-polarisation (Nopen ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channel coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.
An evaluation of fruit and vegetable consumption and cigarette smoking among youth.
Haibach, Jeffrey P; Homish, Gregory G; Collins, R Lorraine; Ambrosone, Christine B; Giovino, Gary A
2015-06-01
Research across the past 4 decades has supported a cross-sectional association between adult cigarette smoking and lower fruit and vegetable consumption (FVC), and emerging research suggests higher FVC may predict cessation. Among youth, findings are limited to a few cross-sectional studies with somewhat mixed results. Here we evaluated the FVC-smoking association among youth both cross-sectionally and longitudinally. We analyzed data from a subsample of the National Longitudinal Survey of Youth 1979: Child and Young Adult. The subsample included adolescents aged 14-18 years at baseline in the year 2004. Multivariable cross-sectional analyses assessed whether baseline FVC was associated with smoking frequency among ever-smokers (n = 578). Longitudinally, the study assessed whether baseline FVC predicted smoking progression among baseline never-smokers who tried a cigarette by 4-year follow-up (n = 388). Multivariable regression models adjusted for age, gender, race/ethnicity, parental education, and health behavior orientation. Cross-sectionally, youth who consumed fruit ≥2 times per day were 53% less likely (RR = 0.47; p < .05) than those who typically did not consume fruit to be in a higher smoking frequency category. Longitudinally, the fruit consumption and smoking association was not significant (RR = 0.61; p = .282). There were no significant associations observed between vegetable consumption and smoking. Fruit consumption, but not vegetable consumption, was inversely associated with smoking frequency cross-sectionally but not longitudinally. Further research is needed to provide information on the consistency of the FVC-smoking relationship among youth and may help to elucidate possible explanatory mechanisms. © The Author 2014. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rakotondravohitra, Laza
2015-08-18
Neutrino physics is one of the most active fields in the domaine of high energy physics during the last century. The need of precise measurement of neutrino-nucleus interactions required by the neutrino oscillation experiments is a an exiting step. These measurements of cross-section are more than essential for neutrino oscillation experiment. Over the year, many measurements from varieties of experiments have been presented. MINERνA is one of the world leaders in measuring cross-section of neutrino and antineutrino -nucleus interactions. MINERνA is a neutrino-nucleus scattering experiment installed in the few-GeV NuMI beam line at Fermilab. In order to study nuclear dependence,more » MINERνA is endowed with different types of solid nuclear targets as well are liquid targets such as helium and water. This thesis presents measurements of cross-section of antineutrino scattering off nucleons using a variety of solid nuclear targets, carbon, iron, lead and also polystyrene scintillator (CH). The data set of antineutrino used for this analysis was taken between March and July 2010 with a total of 1.60X10 20 protons on target. Charged current inclusive interactions were selected by requiring a positive muon and kinematics limitation of acceptance of the muon spectrometer are applied. The analysis requires neutrino energy between 2GeV et 20GeV and the angle of muon θ mu < 17degree . The absolute cross-section # as function of neutrino energy and the differential cross-section dσ/ dx bj measured and shown the corresponding systematics for each nuclear targets. Data results are compared with prediction of the models implemented in the neutrino events generators GENIE 2.6.2 used by the experiment.« less
The electron-furfural scattering dynamics for 63 energetically open electronic states
DOE Office of Scientific and Technical Information (OSTI.GOV)
Costa, Romarly F. da; Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, São Paulo 09210-580; Varella, Márcio T. do N
We report on integral-, momentum transfer- and differential cross sections for elastic and electronically inelastic electron collisions with furfural (C{sub 5}H{sub 4}O{sub 2}). The calculations were performed with two different theoretical methodologies, the Schwinger multichannel method with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR) that now incorporates a further interference (I) term. The SMCPP with N energetically open electronic states (N{sub open}) at either the static-exchange (N{sub open} ch-SE) or the static-exchange-plus-polarisation (N{sub open} ch-SEP) approximation was employed to calculate the scattering amplitudes at impact energies lying between 5 eV and 50 eV, using a channelmore » coupling scheme that ranges from the 1ch-SEP up to the 63ch-SE level of approximation depending on the energy considered. For elastic scattering, we found very good overall agreement at higher energies among our SMCPP cross sections, our IAM-SCAR+I cross sections and the experimental data for furan (a molecule that differs from furfural only by the substitution of a hydrogen atom in furan with an aldehyde functional group). This is a good indication that our elastic cross sections are converged with respect to the multichannel coupling effect for most of the investigated intermediate energies. However, although the present application represents the most sophisticated calculation performed with the SMCPP method thus far, the inelastic cross sections, even for the low lying energy states, are still not completely converged for intermediate and higher energies. We discuss possible reasons leading to this discrepancy and point out what further steps need to be undertaken in order to improve the agreement between the calculated and measured cross sections.« less
Influence of fibre design and curvature on crosstalk in multi-core fibre
NASA Astrophysics Data System (ADS)
Egorova, O. N.; Astapovich, M. S.; Melnikov, L. A.; Salganskii, M. Yu; Mishkin, V. P.; Nishchev, K. N.; Semjonov, S. L.; Dianov, E. M.
2016-03-01
We have studied the influence of cross-sectional structure and bends on optical cross-talk in a multicore fibre. A reduced refractive index layer produced between the cores of such fibre with a small centre-to-centre spacing between neighbouring cores (27 μm) reduces optical cross-talk by 20 dB. The cross-talk level achieved, 30 dB per kilometre of the length of the multicore fibre, is acceptable for a number of applications where relatively small lengths of fibre are needed. Moreover, a significant decrease in optical cross-talk has been ensured by reducing the winding diameter of multicore fibres with identical cores.
Needs and Concerns of Male Combat Veterans with Mild Traumatic Brain Injury
2013-01-01
is bothering me . . . . I bought an old house and I’ve been remodeling it. And I found some old dressers from an old house, I’ve been refin- ishing...EW, Tong EC, Yip SC, Lui WF, Lam CS. Health services needs and quality of life assessment of individuals with brain injuries: a pilot cross -sectional
Unmet Healthcare and Social Services Needs of Older Canadian Adults with Developmental Disabilities
ERIC Educational Resources Information Center
Shooshtari, Shahin; Naghipur, Saba; Zhang, Jin
2012-01-01
The authors sought to create a demographic, socioeconomic, and health-related profile of older (40+) Canadian adults with developmental disabilities (DD) residing in their communities, and to enhance current knowledge of their unmet health and social support services needs. They provide a secondary analysis of cross-sectional data from the 2001…
ERIC Educational Resources Information Center
Al-Bataineh, Mohammad T.
2013-01-01
This study used a cross-sectional survey design to examine the attitudes of Jordanian seventh to twelfth-grade social studies teachers toward technology, and their perceptions of the competency needed for implementing technology in their classrooms. It also explored the relationship between teachers' attitudes and their percptions of competency…
Gender differences in living with schizophrenia. A cross-sectional European multi-site study.
Thornicroft, Graham; Leese, Morven; Tansella, Michele; Howard, Louise; Toulmin, Hilary; Herran, Andres; Schene, Aart
2002-10-01
The EPSILON project (European Psychistric Services: Inputs Linked to Outcomes and Needs) is a cross-sectional study of the clinical and social characteristics, needs, satisfaction with services, quality of life, and service utilisation and costs for people with schizophrenia in five European sites (Amsterdam, Copenhagen, London, Santander, and Verona). This study examined five hypotheses: (1) Men will have more total needs and more unmet needs for: 'accommodation', 'substance misuse', 'psychotic symptoms', 'harm to others', and 'sexual expression', whereas women will have more total needs and more unmet needs in the domains of 'childcare' and 'harm to self'. (2) Caregivers of male patients will show higher rates of psychological distress, and higher scores for 'supervision' and 'urging' than caregivers of female patients. (3) Male and female patients will show similar levels of satisfaction with services, both in total scores and subscores. (4) Male patients will show lower objective quality of life, but similar subjective quality of life compared with women. (5) Service utilization for men and women will differ, and patterns will vary by site. The results confirmed hypotheses 1 (in part) and 3, but failed to support hypotheses 2, 4 and 5. Graphical models were used to generate hypotheses for future research. The implications for planning separate services for male and female schizophrenic patients are discussed.
Scaled plane-wave Born cross sections for atoms and molecules
NASA Astrophysics Data System (ADS)
Tanaka, H.; Brunger, M. J.; Campbell, L.; Kato, H.; Hoshino, M.; Rau, A. R. P.
2016-04-01
Integral cross sections for optically allowed electronic-state excitations of atoms and molecules by electron impact, by applying scaled plane-wave Born models, are reviewed. Over 40 years ago, Inokuti presented an influential review of charged-particle scattering, based on the theory pioneered by Bethe forty years earlier, which emphasized the importance of reliable cross-section data from low eV energies to high keV energies that are needed in many areas of radiation science with applications to astronomy, plasmas, and medicine. Yet, with a couple of possible exceptions, most computational methods in electron-atom scattering do not, in general, overlap each other's validity range in the region from threshold up to 300 eV and, in particular, in the intermediate region from 30 to 300 eV. This is even more so for electron-molecule scattering. In fact this entire energy range is of great importance and, to bridge the gap between the two regions of low and high energy, scaled plane-wave Born models were developed to provide reliable, comprehensive, and absolute integral cross sections, first for ionization by Kim and Rudd and then extended to optically allowed electronic-state excitation by Kim. These and other scaling models in a broad, general application to electron scattering from atoms and molecules, their theoretical basis, and their results for cross sections along with comparison to experimental measurements are reviewed. Where possible, these data are also compared to results from other computational approaches.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wright, R.Q.; Renier, J.P.; Bucholz, J.A.
1995-08-01
The original ANSL-V cross-section libraries (ORNL-6618) were developed over a period of several years for the physics analysis of the ANS reactor, with little thought toward including the materials commonly needed for shielding applications. Materials commonly used for shielding applications include calcium barium, sulfur, phosphorous, and bismuth. These materials, as well as {sup 6}Li, {sup 7}Li, and the naturally occurring isotopes of hafnium, have been added to the ANSL-V libraries. The gamma-ray production and gamma-ray interaction cross sections were completely regenerated for the ANSL-V 99n/44g library which did not exist previously. The MALOCS module was used to collapse the 99n/44gmore » coupled library to the 39n/44g broad- group library. COMET was used to renormalize the two-dimensional (2- D) neutron matrix sums to agree with the one-dimensional (1-D) averaged values. The FRESH module was used to adjust the thermal scattering matrices on the 99n/44g and 39n/44g ANSL-V libraries. PERFUME was used to correct the original XLACS Legendre polynomial fits to produce acceptable distributions. The final ANSL-V 99n/44g and 39n/44g cross-section libraries were both checked by running RADE. The AIM module was used to convert the master cross-section libraries from binary coded decimal to binary format (or vice versa).« less
Nuclear Data Needs for Generation IV Nuclear Energy Systems
NASA Astrophysics Data System (ADS)
Rullhusen, Peter
2006-04-01
Nuclear data needs for generation IV systems. Future of nuclear energy and the role of nuclear data / P. Finck. Nuclear data needs for generation IV nuclear energy systems-summary of U.S. workshop / T. A. Taiwo, H. S. Khalil. Nuclear data needs for the assessment of gen. IV systems / G. Rimpault. Nuclear data needs for generation IV-lessons from benchmarks / S. C. van der Marck, A. Hogenbirk, M. C. Duijvestijn. Core design issues of the supercritical water fast reactor / M. Mori ... [et al.]. GFR core neutronics studies at CEA / J. C. Bosq ... [et al]. Comparative study on different phonon frequency spectra of graphite in GCR / Young-Sik Cho ... [et al.]. Innovative fuel types for minor actinides transmutation / D. Haas, A. Fernandez, J. Somers. The importance of nuclear data in modeling and designing generation IV fast reactors / K. D. Weaver. The GIF and Mexico-"everything is possible" / C. Arrenondo Sánchez -- Benmarks, sensitivity calculations, uncertainties. Sensitivity of advanced reactor and fuel cycle performance parameters to nuclear data uncertainties / G. Aliberti ... [et al.]. Sensitivity and uncertainty study for thermal molten salt reactors / A. Biduad ... [et al.]. Integral reactor physics benchmarks- The International Criticality Safety Benchmark Evaluation Project (ICSBEP) and the International Reactor Physics Experiment Evaluation Project (IRPHEP) / J. B. Briggs, D. W. Nigg, E. Sartori. Computer model of an error propagation through micro-campaign of fast neutron gas cooled nuclear reactor / E. Ivanov. Combining differential and integral experiments on [symbol] for reducing uncertainties in nuclear data applications / T. Kawano ... [et al.]. Sensitivity of activation cross sections of the Hafnium, Tanatalum and Tungsten stable isotopes to nuclear reaction mechanisms / V. Avrigeanu ... [et al.]. Generating covariance data with nuclear models / A. J. Koning. Sensitivity of Candu-SCWR reactors physics calculations to nuclear data files / K. S. Kozier, G. R. Dyck. The lead cooled fast reactor benchmark BREST-300: analysis with sensitivity method / V. Smirnov ... [et al.]. Sensitivity analysis of neutron cross-sections considered for design and safety studies of LFR and SFR generation IV systems / K. Tucek, J. Carlsson, H. Wider -- Experiments. INL capabilities for nuclear data measurements using the Argonne intense pulsed neutron source facility / J. D. Cole ... [et al.]. Cross-section measurements in the fast neutron energy range / A. Plompen. Recent measurements of neutron capture cross sections for minor actinides by a JNC and Kyoto University Group / H. Harada ... [et al.]. Determination of minor actinides fission cross sections by means of transfer reactions / M. Aiche ... [et al.] -- Evaluated data libraries. Nuclear data services from the NEA / H. Henriksson, Y. Rugama. Nuclear databases for energy applications: an IAEA perspective / R. Capote Noy, A. L. Nichols, A. Trkov. Nuclear data evaluation for generation IV / G. Noguère ... [et al.]. Improved evaluations of neutron-induced reactions on americium isotopes / P. Talou ... [et al.]. Using improved ENDF-based nuclear data for candu reactor calculations / J. Prodea. A comparative study on the graphite-moderated reactors using different evaluated nuclear data / Do Heon Kim ... [et al.].
aMC fast: automation of fast NLO computations for PDF fits
NASA Astrophysics Data System (ADS)
Bertone, Valerio; Frederix, Rikkert; Frixione, Stefano; Rojo, Juan; Sutton, Mark
2014-08-01
We present the interface between M adG raph5_ aMC@NLO, a self-contained program that calculates cross sections up to next-to-leading order accuracy in an automated manner, and APPL grid, a code that parametrises such cross sections in the form of look-up tables which can be used for the fast computations needed in the context of PDF fits. The main characteristic of this interface, which we dub aMC fast, is its being fully automated as well, which removes the need to extract manually the process-specific information for additional physics processes, as is the case with other matrix-element calculators, and renders it straightforward to include any new process in the PDF fits. We demonstrate this by studying several cases which are easily measured at the LHC, have a good constraining power on PDFs, and some of which were previously unavailable in the form of a fast interface.
Lee, Shin-Young; Lee, Eunice E
2015-02-01
The purpose of this study was to report the instrument modification and validation processes to make existing health belief model scales culturally appropriate for Korean Americans (KAs) regarding colorectal cancer (CRC) screening utilization. Instrument translation, individual interviews using cognitive interviewing, and expert reviews were conducted during the instrument modification phase, and a pilot test and a cross-sectional survey were conducted during the instrument validation phase. Data analyses of the cross-sectional survey included internal consistency and construct validity using exploratory and confirmatory factor analysis. The main issues identified during the instrument modification phase were (a) cultural and linguistic translation issues and (b) newly developed items reflecting Korean cultural barriers. Cross-sectional survey analyses during the instrument validation phase revealed that all scales demonstrate good internal consistency reliability (Cronbach's alpha=.72~.88). Exploratory factor analysis showed that susceptibility and severity loaded on the same factor, which may indicate a threat variable. Items with low factor loadings in the confirmatory factor analysis may relate to (a) lack of knowledge about fecal occult blood testing and (b) multiple dimensions of the subscales. Methodological, sequential processes of instrument modification and validation, including translation, individual interviews, expert reviews, pilot testing and a cross-sectional survey, were provided in this study. The findings indicate that existing instruments need to be examined for CRC screening research involving KAs.
The supportive care needs for prostate cancer patients in Sarawak.
Cheah, Whye Lian; Ling, Ngok Chuo; Chang, Kam Hock
2016-02-01
This cross-sectional study aimed to determine the prevalence of unmet supportive care needs among prostate cancer patients. The cross-sectional study was conducted among all prostate cancer patients at the Sarawak General Hospital. Interview was done using the Supportive Care Needs Survey-Short Form (SCNS-SF) and the Health Service Utilization Questionnaires (HSUQ). Data were analysed using Statistical Package for the Social Sciences (SPSS) 20. A total of ninety-five patients participated, with majority were aged 65 and above and of primary educational level. The two most frequently reported unmet supportive care needs were "informed about cancer which is under control or diminishing" and "informed about things you can do to help yourself to get well" under the domain Health System and Information. Respondents who were older (65 years and above) had significant lower unmet needs in psychology (P<0.01), and sexuality compared to the younger group below 65 years (P<0.01). Except for physical and daily living, respondents with primary school level had significant lower unmet needs in all domains compared to secondary school level. Respondents with known stages of cancer had higher unmet needs in all domains compared to those who did not know. Healthcare providers should provide more responsive, emotionally sensitive and client-centered care to patients with prostate cancer, particularly in the area of Health System and Information, and psychological support.
Cleary, M; Hunt, G E; Walter, G; Freeman, A
2006-10-01
This cross-sectional study was conducted across inpatient facilities of a metropolitan mental health service in Sydney, Australia. Given shorter lengths of stay in acute inpatient facilities, it is important to ascertain differences between patients' and carers' perceptions of need and support in order to guide delivery of care in the community. The objectives were to: (1) assess the needs of patients recently admitted to hospital and ascertain the level of carer involvement while in hospital; (2) compare the degree of agreement between patients' and carers' perceptions of need and caregiver burden; and (3) determine the relationship between levels of need and carer burden prior to hospitalization. Over a 2-month period, consecutive patients (n = 200) were interviewed using the Camberwell Assessment of Need Short Appraisal Schedule and a modified version of the Involvement Evaluation Questionnaire to assess basic needs and patient perceptions of caregiver burden, respectively. Of the 200 patients interviewed, 68% (n = 135) identified a carer. Patients with schizophrenia had most met needs, those with affective disorders had most unmet needs and patients with other diagnoses recorded the lowest number of needs overall. The level of agreement between patient and carer perceptions of need was low, possibly because of confusion about the definition of need or different views about the support required to fulfil a need. Patients underestimated the consequences of caregiving, especially the impact of strained atmosphere, global burden, worrying about their future and encouragement to undertake an activity, indicating that carers were more burdened than patients perceived them to be.
Photoabsorption and photodissociation of molecules important in the interstellar medium
NASA Technical Reports Server (NTRS)
Lee, Long C.; Suto, Masako
1991-01-01
The photoabsorption, photodissociation, and fluorescence cross sections of interstellar molecules are measured at 90 to 250 nm. These quantitative optical data are needed for the understanding of the formation and destruction processes of molecules under the intense interstellar UV radiation field. Research covering the following topics is presented: (1) fluorescences from photoexcitation of CH4, CH3OH, and CH3SH; (2) NO gamma emission from photoexcitation of NO; (3) photoexcitation cross sections of aromatic molecules; (4) IR emission from UV excitation of HONO2; (5) IR emission from UV excitation of benzene and methyl-derivitives; and (6) IR emission from UV excitation of polycyclic aromatic hydrocarbon molecules.
ERIC Educational Resources Information Center
Al Bataineh, Mohammad; Anderson, Sharon
2015-01-01
This study used a cross-sectional, ten-point Likert-type scale survey design, to examine the perception of Jordanian seventh to twelfth-grade social studies teachers of the competency needed for technology implementation in their classrooms. The instrument for this study was a modified version of a survey developed by Kelly (2003) called the…
ERIC Educational Resources Information Center
Morgan, Debra G.; Kosteniuk, Julie G.; O'Connell, Megan E.; Dal Bello-Haas, Vanina; Stewart, Norma J.; Karunanayake, Chandima
2016-01-01
An understanding of the specific dementia learning needs of home care staff is needed to plan relevant continuing education (CE) programs and supports. The study's objective was to examine frequency and perceived competence in performing 20 dementia-related work activities, and identify CE priorities among home care staff. A cross-sectional survey…
Novak, Iona; Smithers-Sheedy, Hayley; Morgan, Cathy
2012-01-01
Children with cerebral palsy (CP) routinely use assistive equipment to improve their independence. Specialist equipment is expensive and therefore not always available to the child when needed. The aim of this study was to determine whether the assistive equipment needs of children with CP and the associated costs could be predicted. A cross-sectional study using a chart audit was completed. Two hundred forty-two children met eligibility criteria and were included in the study. Data abstracted from files pertained to the child's CP, associated impairments and assistive equipment prescribed. The findings were generated using linear regression modelling. Gross Motor Function Classification System (GMFCS) level [B = 3.01 (95% CI, 2.36-3.57), p = 0.000] and the presence of epilepsy [B = 2.35 (95% CI, 0.64-4.06), p = 0.008] predicted the prescription of assistive equipment. The more severely affected the gross motor function impairment, the more equipment that was required and the more the equipment cost. The equipment needs of children with CP can be predicted for the duration of childhood. This information may be useful for families and for budget and service planning.
Influence of fibre design and curvature on crosstalk in multi-core fibre
DOE Office of Scientific and Technical Information (OSTI.GOV)
Egorova, O N; Astapovich, M S; Semjonov, S L
2016-03-31
We have studied the influence of cross-sectional structure and bends on optical cross-talk in a multicore fibre. A reduced refractive index layer produced between the cores of such fibre with a small centre-to-centre spacing between neighbouring cores (27 μm) reduces optical cross-talk by 20 dB. The cross-talk level achieved, 30 dB per kilometre of the length of the multicore fibre, is acceptable for a number of applications where relatively small lengths of fibre are needed. Moreover, a significant decrease in optical cross-talk has been ensured by reducing the winding diameter of multicore fibres with identical cores. (fiber optics)
Slanted baffle mist eliminator
Vance, Richard F.
1995-11-07
An apparatus for the elimination of mist from off-gas during vitrification f nuclear waste, where baffles are installed on a slant toward the flow of the off-gasses eliminating the need to expand the cross-sectional area of the duct size.
Feasibility of in Vivo SAXS Imaging for Detection of Alzheiemer's Disease
NASA Astrophysics Data System (ADS)
Choi, Mina
Small-angle x-ray scattering (SAXS) imaging has been proposed as a technique to characterize and selectively image structures based on electron density structure which allows for discriminating materials based on their scatter cross sections. This dissertation explores the feasibility of SAXS imaging for the detection of Alzheimer's disease (AD) amyloid plaques. The inherent scatter cross sections of amyloid plaque serve as biomarkers in vivo without the need of injected molecular tags. SAXS imaging can also assist in a better understanding of how these biomarkers play a role in Alzheimer's disease which in turn can lead to the development of more effective disease-modifying therapies. I implement simulations of x-ray transport using Monte Carlo methods for SAXS imaging enabling accurate calculation of radiation dose and image quality in SAXS-computed tomography (CT). I describe SAXS imaging phantoms with tissue-mimicking material and embedded scatter targets as a way of demonstrating the characteristics of SAXS imaging. I also performed a comprehensive study of scattering cross sections of brain tissue from measurements of ex-vivo sections of a wild-type mouse brain and reported generalized cross sections of gray matter, white matter, and corpus callosum obtained and registered by planar SAXS imaging. Finally, I demonstrate the ability of SAXS imaging to locate an amyloid fibril pellet within a brain section. This work contributes to novel application of SAXS imaging for Alzheimer's disease detection and studies its feasibility as an imaging tool for AD biomarkers.
NASA Astrophysics Data System (ADS)
Bartlett, P. L.; Stelbovics, A. T.; Rescigno, T. N.; McCurdy, C. W.
2007-11-01
Calculations are reported for four-body electron-helium collisions and positron-hydrogen collisions, in the S-wave model, using the time-independent propagating exterior complex scaling (PECS) method. The PECS S-wave calculations for three-body processes in electron-helium collisions compare favourably with previous convergent close-coupling (CCC) and time-dependent exterior complex scaling (ECS) calculations, and exhibit smooth cross section profiles. The PECS four-body double-excitation cross sections are significantly different from CCC calculations and highlight the need for an accurate representation of the resonant helium final-state wave functions when undertaking these calculations. Results are also presented for positron-hydrogen collisions in an S-wave model using an electron-positron potential of V12 = - (8 + (r1 - r2)2)-1/2. This model is representative of the full problem, and the results demonstrate that ECS-based methods can accurately calculate scattering, ionization and positronium formation cross sections in this three-body rearrangement collision.
Sisk, Matthew L.; Shea, John J.
2011-01-01
Despite a body of literature focusing on the functionality of modern and stylistically distinct projectile points, comparatively little attention has been paid to quantifying the functionality of the early stages of projectile use. Previous work identified a simple ballistics measure, the Tip Cross-Sectional Area, as a way of determining if a given class of stone points could have served as effective projectile armatures. Here we use this in combination with an alternate measure, the Tip Cross-Sectional Perimeter, a more accurate proxy of the force needed to penetrate a target to a lethal depth. The current study discusses this measure and uses it to analyze a collection of measurements from African Middle Stone Age pointed stone artifacts. Several point types that were rejected in previous studies are statistically indistinguishable from ethnographic projectile points using this new measure. The ramifications of this finding for a Middle Stone Age origin of complex projectile technology is discussed. PMID:21755048
Quasi-heterogeneous efficient 3-D discrete ordinates CANDU calculations using Attila
DOE Office of Scientific and Technical Information (OSTI.GOV)
Preeti, T.; Rulko, R.
2012-07-01
In this paper, 3-D quasi-heterogeneous large scale parallel Attila calculations of a generic CANDU test problem consisting of 42 complete fuel channels and a perpendicular to fuel reactivity device are presented. The solution method is that of discrete ordinates SN and the computational model is quasi-heterogeneous, i.e. fuel bundle is partially homogenized into five homogeneous rings consistently with the DRAGON code model used by the industry for the incremental cross-section generation. In calculations, the HELIOS-generated 45 macroscopic cross-sections library was used. This approach to CANDU calculations has the following advantages: 1) it allows detailed bundle (and eventually channel) power calculationsmore » for each fuel ring in a bundle, 2) it allows the exact reactivity device representation for its precise reactivity worth calculation, and 3) it eliminates the need for incremental cross-sections. Our results are compared to the reference Monte Carlo MCNP solution. In addition, the Attila SN method performance in CANDU calculations characterized by significant up scattering is discussed. (authors)« less
Tallness versus shrinkage: do women shrink with age or grow taller with recent birth date?
Davies, K M; Recker, R R; Stegman, M R; Heaney, R P
1991-10-01
This paper presents evidence that much of the high rate of age-related height loss in women reported in cross-sectional studies is actually a cohort effect rather than an aging effect. Data from a large cross-sectional study of healthy, white American women indicate that there has been a gain in peak adult height of 1.0 cm per decade for several decades from 1900 through 1965. Data from the HES, HANES I, and HANES II studies concur on this point. By contrast, data from a longitudinal study of 191 healthy white U.S. women show only a trivial rate of decline from peak adult height in the fifth and sixth decades of life. In an unselected population, some apparent height loss with age is probably due to disease processes, such as vertebral collapse. Caution is needed in using aging to interpret differences in height and in height-dependent variables, such as bone density, in cross-sectional studies.
An overview of DANCE: a 4II BaF[2] detector for neutron capture measurements at LANSCE.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ullmann, J. L.
2004-01-01
The Detector for Advanced Neutron Capture experiments (DANCE) is a 162-element, 4{pi} BaF{sub 2} array designed to make neutron capture cross-section measurements on rare or radioactive targets with masses as little as 1 mg. Accurate capture cross sections are needed in many research areas, including stellar nucleosynthesis, advanced nuclear fuel cycles, waste transmutation, and other applied programs. These cross sections are difficult to calculate accurately and must be measured. Up to now, except for a few long-lived nuclides there are essentially no differential capture measurements on radioactive nuclei. The DANCE array is located at the Lujan Neutron Scattering Center atmore » LANSCE, which is a continuous-spectrum neutron source with useable energies from below thermal to about 100 keV. Data acquisition is done with 320 fast waveform digitizers. The design and initial performance results, including background minimization, will be discussed.« less
Measurement of the inelastic proton-proton cross-section at √s=7 TeV with the ATLAS detector.
2011-09-06
The dependence of the rate of proton-proton interactions on the centre-of-mass collision energy, √s, is of fundamental importance for both hadron collider physics and particle astrophysics. The dependence cannot yet be calculated from first principles; therefore, experimental measurements are needed. Here we present the first measurement of the inelastic proton-proton interaction cross-section at a centre-of-mass energy, √s, of 7 TeV using the ATLAS detector at the Large Hadron Collider. Events are selected by requiring hits on scintillation counters mounted in the forward region of the detector. An inelastic cross-section of 60.3 ± 2.1 mb is measured for ξ > 5×10⁻⁶, where ξ is calculated from the invariant mass, M(X), of hadrons selected using the largest rapidity gap in the event. For diffractive events, this corresponds to requiring at least one of the dissociation masses to be larger than 15.7 GeV.
Gómez Santos, Santiago Felipe; Estévez Santiago, Rocío; Palacios Gil-Antuñano, Nieves; Leis Trabazo, Maria Rosaura; Tojo Sierra, Rafael; Cuadrado Vives, Carmen; Beltrán de Miguel, Beatriz; Ávila Torres, José Manuel; Varela Moreiras, Gregorio; Casas Esteve, Rafael
2015-12-01
childhood obesity is one of the main public health concerns. The multifactorial and multilevel causes require complex interventions such the community based interventions (CBI). Thao-Child Health Programme is a CBI implemented in Spain since 2007. show the Thao methodology and the latest cross-sectional and longitudinal results. longitudinal cohort study (4 years of follow- up) and cross sectional study. the longitudinal study found an increase of 1% in the overweight prevalence after a follow-up of 4 years of Thao-Programme implementation in 10 municipalities with 6 697 children involved. The cross-sectional study carried out with 20 636 children from 22 municipalities found a childhood overweight prevalence of 26.6%. currently a brake in the increase of childhood overweight prevalence is considered a success due to the high prevalence worldwide. More studies well methodologically performed are needed to know the efficacy of the CBI's in this field. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Measurements of the total cross section of natBe with thermal neutrons from a photo-neutron source
NASA Astrophysics Data System (ADS)
Liu, L. X.; Wang, H. W.; Ma, Y. G.; Cao, X. G.; Cai, X. Z.; Chen, J. G.; Zhang, G. L.; Han, J. L.; Zhang, G. Q.; Hu, J. F.; Wang, X. H.; Li, W. J.; Yan, Z.; Fu, H. J.
2017-11-01
The total neutron cross sections of natural beryllium in the neutron energy region of 0.007 to 0.1 eV were measured by using a time-of-flight (TOF) technique at the Shanghai Institute of Applied Physics (SINAP). The low energy neutrons were obtained by moderating the high energy neutrons from a pulsed photo-neutron source generated from a 16 MeV electron linac. The time dependent neutron background component was determined by employing the 12.8 cm boron-loaded polyethylene (PEB) (5% w.t.) to block neutron TOF path and using the Monte Carlo simulation methods. The present data was compared with the fold Harvey data with the response function of the photo-neutron source (PNS, phase-1). The present measurement of total cross section of natBe for thermal neutrons based on PNS has been developed for the acquisition of nuclear data needed for the Thorium Molten Salt Reactor (TMSR).
Sun, Lingyun; Yang, Yufei; Vertosick, Emily; Jo, SungHwa; Sun, Guilan
2017-01-01
Purpose We aimed to quantify Chinese cancer survivors’ perceived needs for survivorship care and to evaluate whether these needs could impact their willingness to use traditional Chinese medicine (TCM). Methods We conducted a cross-sectional survey with members of the Beijing Anti-Cancer Association in China. We measured perceived needs with the seven-item Brief Chinese Cancer Survivorship Needs Scale that assesses psychological, functional, nutritional, social, body image, pain, and symptom needs. The outcome variable was willingness to use TCM for survivorship care. We performed multivariable logistic regression analyses to evaluate whether perceived needs are associated with willingness. Results A total of 600 patients were invited, with a response rate of 81%. The mean (standard deviation) score of the perceived needs scale (0 to 10) was 4.4 (2.2), with the majority of participants endorsing nutritional (72%), symptom (65%), and psychological (54%) needs. Among survivors, 387 (80%; 95% CI, 76% to 83%) were willing to use TCM for survivorship care. In multivariable analysis, a higher perceived needs score (adjusted odds ratio [OR], 1.33; 95% CI, 1.14 to 1.56; P < .001) was associated with greater willingness to use TCM. Specifically, nutritional (OR, 3.17; 95% CI, 1.79 to 5.62; P < .001) and symptom needs (OR, 3.15; 95% CI, 1.79 to 5.55; P < .001) had the strongest relationship. Conclusion A higher level of perceived needs, especially in the areas of nutrition and symptoms, was associated with greater willingness to use TCM for survivorship care. PMID:29244994
Closing Report for NASA Cooperative Agreement NASA-1-242
NASA Technical Reports Server (NTRS)
Maung, Khin Maung
1999-01-01
Reliable estimates of exposures due to ionizing radiations are of paramount importance in achieving human exploration and development of space, and in several technologically important and scientifically significant areas impacting on industrial and public health. For proper assessment of radiation exposures reliable transport codes are needed. An essential input to the transport codes is the information about the interaction of ions and neutrons with the matter. Most of the information about this interaction is put in by nuclear cross section data. In order to obtain an accurate parameterization of cross sections data, theoretical input is indispensable especially for the processes where there is little or no experimental data available. In the grant period reliable data base was developed and a phenomenological model was developed for the total absorption cross sections valid for any charged/uncharged light, medium and heavy collision pairs valid for the entire energy range. It is gratifying to note the success of the model. The cross sections model has been adopted and is in use in NASA cosmic ray detector development projects, the radiation protection and shielding programs and several DoE laboratories and institutions. A list of the publications based on the work done during the grant period is given below and a sample copy of one of the papers is enclosed with this report.
Constraining the Sea Quark Distributions Through W+/- Cross Section Ratio Measurements at STAR
NASA Astrophysics Data System (ADS)
Posik, Matthew; STAR Collaboration
2017-09-01
Over the years, extractions of parton distribution functions (PDFs) have become more precise, however there are still regions where more data are needed to improve constraints. One such distribution is the sea quark distribution near the valence region, in particular the d / u distribution. Currently, measurements in the high-x region still have large uncertainties and suggest different trends for this distribution. The charged W cross section ratio is sensitive to the unpolarized sea quark distributions and could be used to help constrain the d / u distribution. Through pp collisions, the STAR experiment at RHIC, is well equipped to measure the e+/- leptonic decays of W+/- bosons in the mid-rapidity range
Hydraulic geometry of river cross sections; theory of minimum variance
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)
On-the-fly Doppler broadening of unresolved resonance region cross sections
Walsh, Jonathan A.; Forget, Benoit; Smith, Kord S.; ...
2017-07-29
In this paper, two methods for computing temperature-dependent unresolved resonance region cross sections on-the-fly within continuous-energy Monte Carlo neutron transport simulations are presented. The first method calculates Doppler broadened cross sections directly from zero-temperature average resonance parameters. In a simulation, at each event that requires cross section values, a realization of unresolved resonance parameters is generated about the desired energy and temperature-dependent single-level Breit-Wigner resonance cross sections are computed directly via the analytical Ψ-x Doppler integrals. The second method relies on the generation of equiprobable cross section magnitude bands on an energy-temperature mesh. Within a simulation, the bands are sampledmore » and interpolated in energy and temperature to obtain cross section values on-the-fly. Both of the methods, as well as their underlying calculation procedures, are verified numerically in extensive code-to-code comparisons. Energy-dependent pointwise cross sections calculated with the newly-implemented procedures are shown to be in excellent agreement with those calculated by a widely-used nuclear data processing code. Relative differences at or below 0.1% are observed. Integral criticality benchmark results computed with the proposed methods are shown to reproduce those computed with a state-of-the-art processed nuclear data library very well. In simulations of fast spectrum systems which are highly-sensitive to the representation of cross section data in the unresolved region, k-eigenvalue and neutron flux spectra differences of <10 pcm and <1.0% are observed, respectively. The direct method is demonstrated to be well-suited to the calculation of reference solutions — against which results obtained with a discretized representation may be assessed — as a result of its treatment of the energy, temperature, and cross section magnitude variables as continuous. Also, because there is no pre-processed data to store (only temperature-independent average resonance parameters) the direct method is very memory-efficient. Typically, only a few kB of memory are needed to store all required unresolved region data for a single nuclide. However, depending on the details of a particular simulation, performing URR cross section calculations on-the-fly can significantly increase simulation times. Alternatively, the method of interpolating equiprobable probability bands is demonstrated to produce results that are as accurate as the direct reference solutions, to within arbitrary precision, with high computational efficiency in terms of memory requirements and simulation time. Analyses of a fast spectrum system show that interpolation on a coarse energy-temperature mesh can be used to reproduce reference k-eigenvalue results obtained with cross sections calculated continuously in energy and directly at an exact temperature to within <10 pcm. Probability band data on a mesh encompassing the range of temperatures relevant to reactor analysis usually require around 100 kB of memory per nuclide. Finally, relative to the case in which probability table data generated at a single, desired temperature are used, minor increases in simulation times are observed when probability band interpolation is employed.« less
Scaling Deviations for Neutrino Reactions in Aysmptotically Free Field Theories
DOE R&D Accomplishments Database
Wilczek, F. A.; Zee, A.; Treiman, S. B.
1974-11-01
Several aspects of deep inelastic neutrino scattering are discussed in the framework of asymptotically free field theories. We first consider the growth behavior of the total cross sections at large energies. Because of the deviations from strict scaling which are characteristic of such theories the growth need not be linear. However, upper and lower bounds are established which rather closely bracket a linear growth. We next consider in more detail the expected pattern of scaling deviation for the structure functions and, correspondingly, for the differential cross sections. The analysis here is based on certain speculative assumptions. The focus is on qualitative effects of scaling breakdown as they may show up in the X and y distributions. The last section of the paper deals with deviations from the Callan-Gross relation.
Damage accumulation in closed cross-section, laminated, composite structures
NASA Technical Reports Server (NTRS)
Bucinell, Ronald B.
1996-01-01
The need for safe, lightweight, less expensive, and more reliable launch vehicle components is being driven by the competitiveness of the commercial launch market. The United States has lost 2/3 of the commercial lunch market to Europe. As low cost Russian and Chinese vehicles become available, the US market share could be reduced even further. This international climate is driving the Single Stage To Orbit (SSTO) program at NASA. The goal of the SSTO program is to radically reduce the cost of safe, routine transportation to and from space with a totally reusable launch vehicle designed for low-cost aircraft-like operations. Achieving this goal will require more efficient uses of materials. Composite materials can provide this program with the material and structural efficiencies needed to stay competitive in the international launch market place. In satellite systems the high specific properties, design flexibility, improved corrosion and wear resistance, increased fatigue life, and low coefficient of thermal expansion that are characteristic of composite materials can all be used to improve the overall satellite performance. Some of the satellites that may be able to take advantage of these performance characteristics are the Tethered Satellite Systems (TOSCIFER, AIRSEDS, TSS2, SEDS1, and SEDS2), AXAF, GRO, and the next generation Hubble Space Telescope. These materials can also be utilized in projects at the NASAIMSFC Space Optics Technology and System Center of Excellence. The successful implementation of composite materials requires accurate performance characterization. Materials characterization data for composite materials is typically generated using flat coupons of finite width. At the free edge of these coupons the stress state is exacerbated by the presence of stiffness and geometric discontinuities. The exacerbated stress state has been shown to dominate the damage accumulation in these materials and to have a profound affect on the material constants. Space structures typically have closed cross-sections, absent of free edges. As a result, composite material characterization data generated using finite width flat specimens does not accurately reflect the performance of the composite materials used in a closed cross-section structural configuration. Several investigators have recognized the need to develop characterization techniques for composite materials in closed cross-sectioned structures. In these investigations test methods were developed and cylindrical specimens were evaluated. The behavior of the cylindrical specimens were observed to depart from behavior typical of flat coupons. However, no attempts were made to identify and monitor the progression of damage in these cylindrical specimens during loading. The identification and monitoring of damage is fundamental to the characterization of composite materials in closed cross-section configurations. In the study reported here, a closed cross-sectioned test method was developed to monitor damage progression in 2 in. diameter cylindrical specimens and 1.5 in. finite width flat coupons subjected to quasi-static, tensile loading conditions. Damage in these specimen configurations was monitored using pulse echo ultrasonic, acoustic emission, and X-ray techniques.
Büssing, Arndt; Waßermann, Undine; Christian Hvidt, Niels; Längler, Alfred; Thiel, Michael
2018-04-01
Spirituality is part of the basic needs of all humans, yet often undervalued by health professionals. Less is known about the spiritual needs of mothers of preterm or sick new born children. Identify unmet psychosocial and spiritual needs of these mothers, and to relate these needs to their perceived stress and impairments of life concerns. Anonymous cross-sectional survey with standardized instruments (e.g., Spiritual Needs Questionnaire) among 125 mothers of two paediatric departments in Germany. Mothers felt supported by their partner and hospital staff, and hospital staff assured 82% of them that they must not worry about their child's prognosis. They nevertheless did have specific unmet spiritual needs. Religious Needs and Existentialistic Needs scored lowest, while Giving/Generativity Needs were of moderate and Inner Peace Needs of strongest relevance. With respect to the expected diagnosis and prognosis of their child, there were no significant differences for their secular spiritual needs scores, but significant differences for Religious Needs which scored highest in mothers with children having an unclear prognosis (F=8.6; p=.004). Particularly Inner Peace Needs correlated with their stress perception (r=.34), impairments of life concerns (r=.25) and grief (r=.23). Mothers of sick born/premature children felt supported by the hospital team and their partner, but nevertheless experienced stress and daily life impairments, and particularly have unmet Inner Peace Needs. Addressing mothers' specific needs may help support them in their struggle with their difficult situation avoiding fears and insecurity and thus facilitating positive bonding to their child. Copyright © 2017 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Radiation Transport and Shielding for Space Exploration and High Speed Flight Transportation
NASA Technical Reports Server (NTRS)
Maung, Khin Maung; Trapathi, R. K.
1997-01-01
Transportation of ions and neutrons in matter is of direct interest in several technologically important and scientific areas, including space radiation, cosmic ray propagation studies in galactic medium, nuclear power plants and radiological effects that impact industrial and public health. For the proper assessment of radiation exposure, both reliable transport codes and accurate data are needed. Nuclear cross section data is one of the essential inputs into the transport codes. In order to obtain an accurate parametrization of cross section data, theoretical input is indispensable especially for processes where there is little or no experimental data available. In this grant period work has been done on the studies of the use of relativistic equations and their one-body limits. The results will be useful in choosing appropriate effective one-body equation for reaction calculations. Work has also been done to improve upon the data base needed for the transport codes used in the studies of radiation transport and shielding for space exploration and high speed flight transportation. A phenomenological model was developed for the total absorption cross sections valid for any system of charged and/or uncharged collision pairs for the entire energy range. The success of the model is gratifying. It is being used by other federal agencies, national labs and universities. A list of publications based on the work during the grant period is given below and copies are enclosed with this report.
Herts, Kate L; Khaled, Mona M; Stanton, Annette L
2017-03-01
The primary objective of this review was to summarize the literature regarding factors associated with self-efficacy for disease management (SEDM) in cross-sectional studies and the efficacy/effectiveness of psychosocial interventions that are designed to improve SEDM in adolescent and young adult (AYA) cancer survivors. The secondary aim was to assess the quality of included studies. We conducted a systematic review using PsycINFO and PubMed to identify studies for review. Eligible studies were conducted in AYA cancer survivors ages 15 to 39; included a measure of SEDM assessed as an outcome or in a cross-sectional analysis; and were published in a peer-reviewed, English-language journal. From the 2,910 records screened, 7 cross-sectional studies and 4 intervention studies met criteria for inclusion. Eleven of the 12 SEDM measures in the studies were author-constructed, limiting the ability to draw conclusions across studies. All cross-sectional studies met at least 21 of 26 relevant quality assessment criteria, and intervention studies met between 4 and 11 of 14 criteria. Cross-sectional findings indicate that SEDM is positively associated with health-promoting behaviors and inversely related to physical and mental health problems. The intervention studies demonstrated that behavioral and educational interventions have the potential to increase SEDM. Directions for research include the need for validated measures of SEDM for AYA cancer survivors, as well as interventions that target both the health care team's and the patient's role in promoting SEDM. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
William T. Simpson
2005-01-01
To use small-diameter trees effectively as square timbers, we need to be able to estimate the amount of time it takes for these timbers to air-dry. Since experimental data on estimating air-drying time for small-diameter logs have been developed, this study looked at a way to relate that method to square timbers. Drying times were determined for a group of round cross-...
De Souza, Tanisha; Stevenson, Fiona; King, Michael; Osborn, David; Morant, Nicola
2018-01-01
People bereaved by suicide are at increased risk of suicide, but evidence is lacking that available interventions reduce suicide risk. Few large-scale studies have described the views of suicide-bereaved people regarding their needs for support. Our objective was to explore the nature of young adults’ experiences of support after bereavement by suicide and their views on valued and unhelpful aspects. We conducted a cross-sectional study of staff and students aged 18–40 at 37 United Kingdom (UK) higher educational institutions in 2010, eliciting qualitative responses to two questions probing experiences of support and unmet needs after the suicide of a close contact. We conducted thematic analysis of responses from 420 adults bereaved by suicide, of whom 75% had received support after the loss. We identified three broad descriptive areas corresponding to important aspects of support: value and experiences of the support received; views on specific support needs; and reasons for not seeking support. We found that needs for emotional support exist throughout the social networks of people who die by suicide but are often hidden. Our findings suggest a need for proactive offers of support from family, friends, and professionals after suicide, repeated regularly in case a bereaved person does not feel ready for support early on. PMID:29614053
Andersson, Els-Marie; Axelsson, Stefan; Katsaris, Kristoffer P
2016-07-01
To describe the arch morphology and the prevalence and severity of malocclusions in 8-year-old children with DS, and to evaluate their need for treatment using the Norwegian Need for Orthodontic Treatment Index (NOTI), and comparing the findings with a control group. This population-based cross-sectional study was part of a national prospective study evaluating upper airway function, hearing, dental, and craniofacial characteristics in a cohort of children with DS in Norway. The cohort consisted of 32 children with DS and represented 57% of all children born with DS in Norway in 2002. Dental arch morphology and malocclusion were assessed on dental casts. Data were collected prospectively at the TAKO-centre, National Resource Center for Oral Health in Rare Medical Conditions. All the children with DS (100%) had objectively assessed needs for orthodontic treatment, compared with 30% of the normative comparison group. Among the children with DS, 68% were objectively categorized as being in "great need" (Category B) for treatment and the 75% were categorized as having "obvious need" (Category C). In comparison, only 20% of children without DS were in Category B, and 44% were in Category C. This study indicates significantly higher prevalence and severity of malocclusions in 8-year-old children with DS compared with control group. © 2016 Special Care Dentistry Association and Wiley Periodicals, Inc.
Transverse liquid fuel jet breakup, burning, and ignition. M.S. Thesis
NASA Technical Reports Server (NTRS)
Li, Hsi-Shang
1990-01-01
An analytical study of the breakup, burning, and ignition of liquid fuels injected transversely into a hot air stream is conducted. The non-reacting liquid jet breakup location is determined by the local sonic point criterion. Two models, one employing analysis of an elliptical jet cross-section and the other employing a two-dimensional blunt body to represent the transverse jet, were used for sonic point calculations. An auxiliary criterion based on surface tension stability is used as a separate means of determining the breakup location. For the reacting liquid jet problem, a diffusion flame supported by a one-step chemical reaction within the gaseous boundary layer is solved along the ellipse surface in subsonic cross flow. Typical flame structures and concentration profiles were calculated for various locations along the jet cross-section as a function of upstream Mach numbers. The integration reaction rate along the jet cross-section is used to predict ignition position, which is found to be situated near the stagnation point. While a multi-step reaction is needed to represent the ignition process more accurately, the present calculation does yield reasonable predictions concerning ignition along a curved surface.
Association between vertebral cross-sectional area and lumbar lordosis angle in adolescents.
Wren, Tishya A L; Aggabao, Patricia C; Poorghasamians, Ervin; Chavez, Thomas A; Ponrartana, Skorn; Gilsanz, Vicente
2017-01-01
Lumbar lordosis (LL) is more prominent in women than in men, but the mechanisms responsible for this discrepancy are poorly defined. A recent study indicates that newborn girls have smaller vertebral cross-sectional area (CSA) when compared to boys-a difference that persists throughout life and is independent of body size. We determined the relations between vertebral cross-sectional area (CSA) and LL angle and whether sex differences in lumbar lordosis are related to sex differences in vertebral CSA. Using multi-planar magnetic resonance imaging (MRI), we measured vertebral cross-sectional area (CSA) and vertebral height of the spine of 40 healthy boys and 40 girls, ages 9-13 years. Measures of the CSA of the lumbar vertebrae significantly differed between sexes (9.38 ± 1.46 vs. 7.93 ± 0.69 in boys and girls, respectively; P < 0.0001), while the degree of LL was significantly greater in girls than in boys (23.7 ± 6.1 vs. 27.6 ± 8.0 in boys and girls, respectively; P = 0.02). When all subjects were analyzed together, values for LL angle were negatively correlated to vertebral CSA (r = -0.47; P < 0.0001); this was also true when boys and girls were analyzed separately. Multivariate regression analysis indicated that vertebral CSA was independently associated with LL, even after accounting for sex, age, height or vertebral height, and weight. Similar negative relations were present when thoracic vertebrae were analyzed (Model P < 0.0001, R2 = 0.37, thoracic vertebral CSA slope P < 0.0001), suggesting that deficient vertebral cross-sectional dimensions are not merely the consequence of the anterior lumbar curvature. We conclude that vertebral CSA is negatively associated with LL, and that the greater degree of LL in females could, at least in part, be due to smaller vertebral cross-sectional dimensions. Studies are needed to examine the potential relations between vertebral CSA and spinal conditions known to be associated with increased LL, such as spondylolysis and spondylolisthesis.
Prediction of energy expenditure and physical activity in preschoolers
USDA-ARS?s Scientific Manuscript database
Accurate, nonintrusive, and feasible methods are needed to predict energy expenditure (EE) and physical activity (PA) levels in preschoolers. Herein, we validated cross-sectional time series (CSTS) and multivariate adaptive regression splines (MARS) models based on accelerometry and heart rate (HR) ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zylstra, A. B.; Frenje, J. A.; Gatu Johnson, M.
Few-body nuclear physics often relies upon phenomenological models, with new efforts at the ab initio theory reported recently; both need high-quality benchmark data, particularly at low center-of-mass energies. We use high-energy-density plasmas to measure the proton spectra from 3He + T and 3He + 3He fusion. The data disagree with R -matrix predictions constrained by neutron spectra from T + T fusion. Here, we present a new analysis of the 3He + 3He proton spectrum; these benchmarked spectral shapes should be used for interpreting low-resolution data, such as solar fusion cross-section measurements.
NASA Astrophysics Data System (ADS)
Zylstra, A. B.; Frenje, J. A.; Gatu Johnson, M.; Hale, G. M.; Brune, C. R.; Bacher, A.; Casey, D. T.; Li, C. K.; McNabb, D.; Paris, M.; Petrasso, R. D.; Sangster, T. C.; Sayre, D. B.; Séguin, F. H.
2017-12-01
Few-body nuclear physics often relies upon phenomenological models, with new efforts at the ab initio theory reported recently; both need high-quality benchmark data, particularly at low center-of-mass energies. We use high-energy-density plasmas to measure the proton spectra from 3He +T and 3He + 3He fusion. The data disagree with R -matrix predictions constrained by neutron spectra from T +T fusion. We present a new analysis of the 3He + 3He 3 proton spectrum; these benchmarked spectral shapes should be used for interpreting low-resolution data, such as solar fusion cross-section measurements.
Zylstra, A. B.; Frenje, J. A.; Gatu Johnson, M.; ...
2017-11-29
Few-body nuclear physics often relies upon phenomenological models, with new efforts at the ab initio theory reported recently; both need high-quality benchmark data, particularly at low center-of-mass energies. We use high-energy-density plasmas to measure the proton spectra from 3He + T and 3He + 3He fusion. The data disagree with R -matrix predictions constrained by neutron spectra from T + T fusion. Here, we present a new analysis of the 3He + 3He proton spectrum; these benchmarked spectral shapes should be used for interpreting low-resolution data, such as solar fusion cross-section measurements.
NASA Technical Reports Server (NTRS)
Lin, Zi-wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most effect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space exploration.
NASA Technical Reports Server (NTRS)
Lin, Zi-Wei
2004-01-01
Space radiation from cosmic ray particles is one of the main challenges for long-term human space explorations such as a permanent moon base or a trip to Mars. Material shielding may provide significant radiation protection to astronauts, and models have been developed in order to evaluate the effectiveness of different shielding materials and to predict radiation environment inside the spacecraft. In this study we determine the nuclear fragmentation cross sections which will most affect the radiation risk behind typical radiation shielding materials. These cross sections thus need more theoretical studies and accurate experimental measurements in order for us to more precisely predict the radiation risk in human space explorations.
NASA Technical Reports Server (NTRS)
Smith, Peter L.; Rufus, J.; Yoshino, K.; Parkinson, W. H.; Stark, Glenn; Pickering, Juliet C.; Thorne, A. P.
2002-01-01
We report high-resolution laboratory measurements of photoabsorption cross sections of CO, N2, and SO2 in the wavelength range 80 to 320 nm. The motivation is to provide the quantitative data that are needed to analyze observations of absorption by, and to model photochemical processes in, the interstellar medium and a number of planetary atmospheres. Because of the high resolution of the spectrometers used, we can minimize distortion of the spectrum that occurs when instrument widths are greater than the widths of spectral features being measured. In many cases, we can determine oscillator strengths of individual rotational lines - a unique feature of our work.
Analytic integration of real-virtual counterterms in NNLO jet cross sections I
NASA Astrophysics Data System (ADS)
Aglietti, Ugo; Del Duca, Vittorio; Duhr, Claude; Somogyi, Gábor; Trócsányi, Zoltán
2008-09-01
We present analytic evaluations of some integrals needed to give explicitly the integrated real-virtual counterterms, based on a recently proposed subtraction scheme for next-to-next-to-leading order (NNLO) jet cross sections. After an algebraic reduction of the integrals, integration-by-parts identities are used for the reduction to master integrals and for the computation of the master integrals themselves by means of differential equations. The results are written in terms of one- and two-dimensional harmonic polylogarithms, once an extension of the standard basis is made. We expect that the techniques described here will be useful in computing other integrals emerging in calculations in perturbative quantum field theories.
Needs of fathers during labour and childbirth: A cross-sectional study.
Eggermont, Katrijn; Beeckman, Dimitri; Van Hecke, Ann; Delbaere, Ilse; Verhaeghe, Sofie
2017-08-01
Fathers play an important role in the childbearing process, but are sometimes sidelined by midwives. The objectives were: identify fathers' needs during the labor and childbirth process; determine if their needs were met by midwives; and identify variables influencing these needs. The questionnaire was designed based on a systematic literature search and validated by a multistage consensus method. Data were collected during a cross-sectional study in two maternity wards in Belgium, where a medical-led model is used. Fathers present during natural childbirth were recruited via consecutive sampling. Based on multivariate analyses, fathers with a higher education level and multiparous fathers needed less information about the process of birth compared to less educated fathers (p<0.05; OR=4.08; 95% CI=1.02-16.31) or first-time fathers (p<0.001; OR=0.04; 95% CI=0.01-0.18). For multiparous fathers, a tour of the delivery room was less important than for primiparous fathers (p=0.005; OR=0.14; 95% CI=0.03-0.54). Married fathers needed less information on how to support their partners physically (p<0.005; OR=0.18; 95% CI=0.06-0.59) and emotionally (p=0.01; OR=0.24; 95% CI=0.08-0.72) compared to cohabiting fathers. Information needs are more important to fathers compared to needs focusing on the birth experience or their involvement. Socio-demographic variables like educational level, parity, and marital status were associated with fathers' needs. Midwives need to be aware of fathers' needs during the birth process and to fulfill these needs appropriately. Copyright © 2016 Australian College of Midwives. Published by Elsevier Ltd. All rights reserved.
Miller, David S.; Weiser, Glen C.; Aune, Keith; Roeder, Brent; Atkinson, Mark; Anderson, Neil; Roffe, Thomas J.; Keating, Kim A.; Chapman, Phillip L.; Kimberling, Cleon; Rhyan, Jack; Clarke, P. Ryan
2011-01-01
Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents. PMID:22195293
Miller, David S; Weiser, Glen C; Aune, Keith; Roeder, Brent; Atkinson, Mark; Anderson, Neil; Roffe, Thomas J; Keating, Kim A; Chapman, Phillip L; Kimberling, Cleon; Rhyan, Jack; Clarke, P Ryan
2011-01-01
Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents.
Miller, David S.; Weiser, Glen C.; Aune, Keith; Roeder, Brent; Atkinson, Mark; Anderson, Neil; Roffe, Thomas J.; Keating, Kim A.; Chapman, Phillip L.; Kimberling, Cleon; Rhyan, Jack C.; Clarke, P. Ryan
2011-01-01
Transmission of infectious agents from livestock reservoirs has been hypothesized to cause respiratory disease outbreaks in bighorn sheep (Ovis canadensis), and land management policies intended to limit this transmission have proven controversial. This cross-sectional study compares the infectious agents present in multiple populations of bighorn sheep near to and distant from their interface with domestic sheep (O. aries) and domestic goat (Capra hircus) and provides critical baseline information needed for interpretations of cross-species transmission risks. Bighorn sheep and livestock shared exposure to Pasteurellaceae, viral, and endoparasite agents. In contrast, although the impact is uncertain, Mycoplasma sp. was isolated from livestock but not bighorn sheep. These results may be the result of historic cross-species transmission of agents that has resulted in a mosaic of endemic and exotic agents. Future work using longitudinal and multiple population comparisons is needed to rigorously establish the risk of outbreaks from cross-species transmission of infectious agents.
Heterosexual Interests of Suburban Youth
ERIC Educational Resources Information Center
Broderick, Carlfred B.
1971-01-01
Extensive cross sectional data suggest a real continuity between prepubertal attitudes and experience and those of adolescence. The preteen years (10-13) represent a period of preparation for later heterosexual involvement. These findings suggest need to modify traditional points of view regarding patterns of sociosexual development. (Author/CJ)
Semi-inclusive production of two back-to-back hadron pairs in e+e- annihilation revisited
NASA Astrophysics Data System (ADS)
Matevosyan, Hrayr H.; Bacchetta, Alessandro; Boer, Daniël; Courtoy, Aurore; Kotzinian, Aram; Radici, Marco; Thomas, Anthony W.
2018-04-01
The cross section for back-to-back hadron pair production in e+e- annihilation provides access to the dihadron fragmentation functions (DiFF) needed to extract nucleon parton distribution functions from the semi-inclusive deep inelastic scattering (SIDIS) experiments with two detected final state hadrons. Particular attention is given to the so-called interference DiFF (IFF), which makes it possible to extract the transversity parton distribution of the nucleon in the collinear framework. However, previously unnoticed discrepancies were recently highlighted between the definitions of the IFFs appearing in the collinear kinematics when reconstructed from DiFFs entering the unintegrated fully differential cross sections of SIDIS and e+e- annihilation processes. In this work, to clarify this problem we re-derive the fully differential cross section for e+e- annihilation at the leading-twist approximation. We find a mistake in the definition of the kinematics in the original expression that systematically affects a subset of terms and that leads to two significant consequences. First, the discrepancy between the IFF definitions in the cross sections for SIDIS and e+e- annihilation is resolved. Second, the previously derived azimuthal asymmetry for accessing the helicity dependent DiFF G1⊥ in e+e- annihilation vanishes, which explains the nonobservation of this asymmetry in the recent experimental searches by the BELLE collaboration. We discuss the recently proposed alternative option to extract G1⊥.
NASA Astrophysics Data System (ADS)
Shimobaba, Tomoyoshi; Kakue, Takashi; Ito, Tomoyoshi
2014-06-01
We propose acceleration of color computer-generated holograms (CGHs) from three-dimensional (3D) scenes that are expressed as texture (RGB) and depth (D) images. These images are obtained by 3D graphics libraries and RGB-D cameras: for example, OpenGL and Kinect, respectively. We can regard them as two-dimensional (2D) cross-sectional images along the depth direction. The generation of CGHs from the 2D cross-sectional images requires multiple diffraction calculations. If we use convolution-based diffraction such as the angular spectrum method, the diffraction calculation takes a long time and requires large memory usage because the convolution diffraction calculation requires the expansion of the 2D cross-sectional images to avoid the wraparound noise. In this paper, we first describe the acceleration of the diffraction calculation using "Band-limited double-step Fresnel diffraction," which does not require the expansion. Next, we describe color CGH acceleration using color space conversion. In general, color CGHs are generated on RGB color space; however, we need to repeat the same calculation for each color component, so that the computational burden of the color CGH generation increases three-fold, compared with monochrome CGH generation. We can reduce the computational burden by using YCbCr color space because the 2D cross-sectional images on YCbCr color space can be down-sampled without the impairing of the image quality.
Niedhammer, I; Chea, M
2003-01-01
Background: Psychosocial factors at work have been found to be significant contributors to health, especially cardiovascular health. Aims: To explore the relation between psychosocial factors at work and self reported health, using cross sectional and prospective analyses for a large occupational cohort of men and women. Methods: Psychosocial factors at work were evaluated using the Karasek questionnaire, designed to measure psychological demands, decision latitude, social support, and physical demands. Self reported health was used as health outcome. Covariates included chronic diseases, and sociodemographic, occupational, and behavioural factors. The cross sectional and prospective analyses concerned respectively 11 447 and 7664 workers. Men and women were analysed separately. Results: Cross sectional analysis revealed significant associations between psychological demands, decision latitude, social support, and physical demands, and self reported health for both men and women. Prospective analysis showed that high psychological demands for both genders, low decision authority for men, and low social support and high physical demands for women were predictive of poor self reported health. These results were independent of potential confounding variables. Conclusions: Results highlight the predictive effects of psychosocial factors at work on self reported health in a one year follow up study. They also underline the need for longitudinal study design and separate analyses for men and women in the field of psychosocial factors at work. PMID:12819285
Improved Neutronics Treatment of Burnable Poisons for the Prismatic HTR
DOE Office of Scientific and Technical Information (OSTI.GOV)
Y. Wang; A. A. Bingham; J. Ortensi
2012-10-01
In prismatic block High Temperature Reactors (HTR), highly absorbing material such a burnable poison (BP) cause local flux depressions and large gradients in the flux across the blocks which can be a challenge to capture accurately with traditional homogenization methods. The purpose of this paper is to quantify the error associated with spatial homogenization, spectral condensation and discretization and to highlight what is needed for improved neutronics treatments of burnable poisons for the prismatic HTR. A new triangular based mesh is designed to separate the BP regions from the fuel assembly. A set of packages including Serpent (Monte Carlo), Xuthosmore » (1storder Sn), Pronghorn (diffusion), INSTANT (Pn) and RattleSnake (2ndorder Sn) is used for this study. The results from the deterministic calculations show that the cross sections generated directly in Serpent are not sufficient to accurately reproduce the reference Monte Carlo solution in all cases. The BP treatment produces good results, but this is mainly due to error cancellation. However, the Super Cell (SC) approach yields cross sections that are consistent with cross sections prepared on an “exact” full core calculation. In addition, very good agreement exists between the various deterministic transport and diffusion codes in both eigenvalue and power distributions. Future research will focus on improving the cross sections and quantifying the error cancellation.« less
NASA Astrophysics Data System (ADS)
Kohri, H.; Shiu, S. H.; Chang, W. C.; Yanai, Y.; Ahn, D. S.; Ahn, J. K.; Chen, J. Y.; Daté, S.; Ejiri, H.; Fujimura, H.; Fujiwara, M.; Fukui, S.; Gohn, W.; Hicks, K.; Hosaka, A.; Hotta, T.; Hwang, S. H.; Imai, K.; Ishikawa, T.; Joo, K.; Kato, Y.; Kon, Y.; Lee, H. S.; Maeda, Y.; Mibe, T.; Miyabe, M.; Morino, Y.; Muramatsu, N.; Nakano, T.; Nakatsugawa, Y.; Nam, S. i.; Niiyama, M.; Noumi, H.; Ohashi, Y.; Ohta, T.; Oka, M.; Parker, J. D.; Rangacharyulu, C.; Ryu, S. Y.; Sawada, T.; Shimizu, H.; Strokovsky, E. A.; Sugaya, Y.; Sumihama, M.; Tsunemi, T.; Uchida, M.; Ungaro, M.; Wang, S. Y.; Yosoi, M.; LEPS Collaboration
2018-05-01
Differential cross sections and photon-beam asymmetries for the γ → p →π-Δ++(1232 ) reaction have been measured for 0.7
Barbagallo, M; Musumarra, A; Cosentino, L; Maugeri, E; Heinitz, S; Mengoni, A; Dressler, R; Schumann, D; Käppeler, F; Colonna, N; Finocchiaro, P; Ayranov, M; Damone, L; Kivel, N; Aberle, O; Altstadt, S; Andrzejewski, J; Audouin, L; Bacak, M; Balibrea-Correa, J; Barros, S; Bécares, V; Bečvář, F; Beinrucker, C; Berthoumieux, E; Billowes, J; Bosnar, D; Brugger, M; Caamaño, M; Calviani, M; Calviño, F; Cano-Ott, D; Cardella, R; Casanovas, A; Castelluccio, D M; Cerutti, F; Chen, Y H; Chiaveri, E; Cortés, G; Cortés-Giraldo, M A; Cristallo, S; Diakaki, M; Domingo-Pardo, C; Dupont, E; Duran, I; Fernandez-Dominguez, B; Ferrari, A; Ferreira, P; Furman, W; Ganesan, S; García-Rios, A; Gawlik, A; Glodariu, T; Göbel, K; Gonçalves, I F; González-Romero, E; Griesmayer, E; Guerrero, C; Gunsing, F; Harada, H; Heftrich, T; Heyse, J; Jenkins, D G; Jericha, E; Katabuchi, T; Kavrigin, P; Kimura, A; Kokkoris, M; Krtička, M; Leal-Cidoncha, E; Lerendegui, J; Lederer, C; Leeb, H; Lo Meo, S; Lonsdale, S J; Losito, R; Macina, D; Marganiec, J; Martínez, T; Massimi, C; Mastinu, P; Mastromarco, M; Mazzone, A; Mendoza, E; Milazzo, P M; Mingrone, F; Mirea, M; Montesano, S; Nolte, R; Oprea, A; Pappalardo, A; Patronis, N; Pavlik, A; Perkowski, J; Piscopo, M; Plompen, A; Porras, I; Praena, J; Quesada, J; Rajeev, K; Rauscher, T; Reifarth, R; Riego-Perez, A; Rout, P; Rubbia, C; Ryan, J; Sabate-Gilarte, M; Saxena, A; Schillebeeckx, P; Schmidt, S; Sedyshev, P; Smith, A G; Stamatopoulos, A; Tagliente, G; Tain, J L; Tarifeño-Saldivia, A; Tassan-Got, L; Tsinganis, A; Valenta, S; Vannini, G; Variale, V; Vaz, P; Ventura, A; Vlachoudis, V; Vlastou, R; Vollaire, J; Wallner, A; Warren, S; Weigand, M; Weiß, C; Wolf, C; Woods, P J; Wright, T; Žugec, P
2016-10-07
The energy-dependent cross section of the ^{7}Be(n,α)^{4}He reaction, of interest for the so-called cosmological lithium problem in big bang nucleosynthesis, has been measured for the first time from 10 meV to 10 keV neutron energy. The challenges posed by the short half-life of ^{7}Be and by the low reaction cross section have been overcome at n_TOF thanks to an unprecedented combination of the extremely high luminosity and good resolution of the neutron beam in the new experimental area (EAR2) of the n_TOF facility at CERN, the availability of a sufficient amount of chemically pure ^{7}Be, and a specifically designed experimental setup. Coincidences between the two alpha particles have been recorded in two Si-^{7}Be-Si arrays placed directly in the neutron beam. The present results are consistent, at thermal neutron energy, with the only previous measurement performed in the 1960s at a nuclear reactor. The energy dependence reported here clearly indicates the inadequacy of the cross section estimates currently used in BBN calculations. Although new measurements at higher neutron energy may still be needed, the n_TOF results hint at a minor role of this reaction in BBN, leaving the long-standing cosmological lithium problem unsolved.
NASA Astrophysics Data System (ADS)
Wachter, J. A.; Miranda, P. A.; Morales, J. R.; Cancino, S. A.; Correa, R.
2015-02-01
The experimental production cross section for the reaction natZn(p,x)67Ga has been measured in the energy range from 1.678 to 2.444 MeV. The methodology used in this work is based on characteristic X-ray emitted after irradiation by the daughter nuclei that decays by electron capture (EC) and the use of a complementary PIXE experiment. By doing so, expressions needed to determine cross section values are simplified since experimental factors such as geometric setup and an detector efficiency are avoided. 67Ga is a radionuclide particularly suited for this method since it decays by electron capture in 100% and the subsequent characteristic X-ray emission is easily detected. Natural zinc targets were fabricated by PVD technique and afterwards their thicknesses were determined by Rutherford Backscattering Spectrometry. Cross sections measurements were carried out by using the Van de Graaff accelerator located at Faculty of Sciences, University of Chile. It was found that our data for the natZn(p,x)67Ga reaction are, in general, in good agreement when compared to existing experimental data and to those calculated ALICE/ASH nuclear code. On the other hand, values predicted by Talys-1.6 are showing systematically lower magnitudes than our measured data.
2018-01-01
Victim support services, in mature societies, aim to help victims recover after suffering a traumatic event. The effectiveness of victim support has traditionally been evaluated through rates of service utilization and incidence of psychopathology such as posttraumatic stress disorder. The current study, instead, inquires into service users’ unmet needs and satisfaction, and identifies factors that mediate such subjective measures, using data from a national cross-sectional survey on victims and surviving families of violent crime in Taiwan in 2011. The results reveal: 1) a gap between available and expected services, and 2) a correlation between service utilization and satisfaction, both consistent with previous studies. In addition, the current study identifies unsatisfied service users: They are homicidally bereaved, live with their spouse, suffer from post-crime financial distress and are still waiting for a court verdict on the incident. Victim support that helps victims heal through tailored services incorporating relationship counseling is proposed. PMID:29466463
Slow Control System for the NIFFTE Collaboration TPC
NASA Astrophysics Data System (ADS)
Ringle, Erik; Niffte Collaboration Collaboration
2011-10-01
As world energy concerns continue to dominate public policy in the 21st century, the need for cleaner and more efficient nuclear power is necessary. In order to effectively design and implement plans for generation IV nuclear reactors, more accurate fission cross-section measurements are necessary. The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration, in an effort to meet this need, has constructed a Time Projection Chamber (TPC) which aims to reduce the uncertainty of the fission cross-section to less than 1%. Using the Maximum Integration Data Acquisition System (MIDAS) framework, slow control measurements are integrated into a single interface to facilitate off-site monitoring. The Hart Scientific 1560 Black Stack will be used with two 2564 Thermistor Scanner Modules to monitor internal temperature of the TPC. A Prologix GPIB to Ethernet controller will be used to interface the hardware with MIDAS. This presentation will detail the design and implementation of the slow control system for the TPC. This work was supported by the U.S. Department of Energy Division of Energy Research.
A study for the installation of the TEXT heavy-ion beam probe on DIII-D
NASA Astrophysics Data System (ADS)
Edmonds, P. H.; Solano, E. R.; Bravenec, R. V.; Wootton, A. J.; Schoch, P. M.; Crowley, T. P.; Hickok, R. L.; West, W. P.; Leuer, J.; Anderson, P.
1997-01-01
An assessment of the feasibility of installing the TEXT 2 MeV heavy-ion beam probe on the DIII-D tokamak has been completed. Detailed drawings of the machine cross section were imported into the CAD application AutoCAD. A set of programs written in AutoLisp were used to generate trajectories. Displays of the accessible cross section of the plasma, scan lines for the entire range of primary beam energy and injection angle ranges, and sample-volume dimensions can be rapidly generated. Because of the large deflection between the primary input beam and the emergent secondary beam, either the analyzer needs to be tracked over a ±20° angle or secondary poloidal deflector plates need to be installed at the exit port. Toroidal deflector plates will be installed at both the injection and exit ports to compensate for toroidal displacements and deflections. The sample volumes generated by this procedure are within a few centimeters of the locations derived from a full three-dimensional calculation.
Collisional perturbation of radio-frequency E1 transitions in an atomic beam of dysprosium
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cingoez, A.; Lapierre, Alain; Nguyen, A.-T.
2005-12-15
We have studied collisional perturbations of radio-frequency (rf) electric-dipole (E1) transitions between the nearly degenerate opposite-parity levels in atomic dysprosium (Dy) in the presence of 10 to 80 {mu}Torr of H{sub 2}, N{sub 2}, He, Ar, Ne, Kr, and Xe. Collisional broadening and shift of the resonance, as well as the attenuation of the signal amplitude are observed to be proportional to the foreign-gas density with the exception of H{sub 2} and Ne, for which no shifts were observed. Corresponding rates and cross sections are presented. In addition, rates and cross sections for O{sub 2} are extracted from measurements usingmore » air as foreign gas. The primary motivation for this study is the need for accurate determination of the shift rates, which are needed in a laboratory search for the temporal variation of the fine-structure constant [A. T. Nguyen, D. Budker, S. K. Lamoreaux, and J. R. Torgerson, Phys. Rev. A 69, 22105 (2004)].« less
ERIC Educational Resources Information Center
Bellin, Melissa H.; Osteen, Philip; Heffernan, Caitlin; Levy, Judy M.; Snyder-Vogel, Mary E.
2011-01-01
A family-centered approach to health care for children with special health care needs (CSHCN) is widely acknowledged as the ideal model of service delivery, but less is known about the actual practice of family-centered care (FCC), especially from the viewpoints of parents and health care professionals. This cross-sectional research compared…
Neutron-induced fission cross section of 240Pu from 0.5 MeV to 3 MeV
NASA Astrophysics Data System (ADS)
Salvador-Castiñeira, P.; Bryś, T.; Eykens, R.; Hambsch, F.-J.; Göök, A.; Moens, A.; Oberstedt, S.; Sibbens, G.; Vanleeuw, D.; Vidali, M.; Pretel, C.
2015-07-01
240Pu has recently been pointed out by a sensitivity study of the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency (NEA) to be one of the isotopes whose fission cross section lacks accuracy to meet the upcoming needs for the future generation of nuclear power plants (GEN-IV). In the High Priority Request List (HPRL) of the OECD, it is suggested that the knowledge of the 240Pu(n ,f ) cross section should be improved to an accuracy within 1-3 %, compared to the present 5%. A measurement of the 240Pu cross section has been performed at the Van de Graaff accelerator of the Joint Research Center (JRC) Institute for Reference Materials and Measurements (IRMM) using quasi-monoenergetic neutrons in the energy range from 0.5 MeV to 3 MeV. A twin Frisch-grid ionization chamber (TFGIC) has been used in a back-to-back configuration as fission fragment detector. The 240Pu(n ,f ) cross section has been normalized to three different isotopes: 237Np(n ,f ) , 235U (n ,f ) , and 238U (n ,f ) . Additionally, the secondary standard reactions were benchmarked through measurements against the primary standard reaction 235U (n ,f ) in the same geometry. A comprehensive study of the corrections applied to the data and the associated uncertainties is given. The results obtained are in agreement with previous experimental data at the threshold region. For neutron energies higher than 1 MeV, the results of this experiment are slightly lower than the ENDF/B-VII.1 evaluation, but in agreement with the experiments of Laptev et al. (2004) as well as Staples and Morley (1998).
Digital floodplain mapping and an analysis of errors involved
Hamblen, C.S.; Soong, D.T.; Cai, X.
2007-01-01
Mapping floodplain boundaries using geographical information system (GIS) and digital elevation models (DEMs) was completed in a recent study. However convenient this method may appear at first, the resulting maps potentially can have unaccounted errors. Mapping the floodplain using GIS is faster than mapping manually, and digital mapping is expected to be more common in the future. When mapping is done manually, the experience and judgment of the engineer or geographer completing the mapping and the contour resolution of the surface topography are critical in determining the flood-plain and floodway boundaries between cross sections. When mapping is done digitally, discrepancies can result from the use of the computing algorithm and digital topographic datasets. Understanding the possible sources of error and how the error accumulates through these processes is necessary for the validation of automated digital mapping. This study will evaluate the procedure of floodplain mapping using GIS and a 3 m by 3 m resolution DEM with a focus on the accumulated errors involved in the process. Within the GIS environment of this mapping method, the procedural steps of most interest, initially, include: (1) the accurate spatial representation of the stream centerline and cross sections, (2) properly using a triangulated irregular network (TIN) model for the flood elevations of the studied cross sections, the interpolated elevations between them and the extrapolated flood elevations beyond the cross sections, and (3) the comparison of the flood elevation TIN with the ground elevation DEM, from which the appropriate inundation boundaries are delineated. The study area involved is of relatively low topographic relief; thereby, making it representative of common suburban development and a prime setting for the need of accurately mapped floodplains. This paper emphasizes the impacts of integrating supplemental digital terrain data between cross sections on floodplain delineation. ?? 2007 ASCE.
Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chadwick, M.B.; Blann, M.; Cox, L.
1995-04-11
A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements wheremore » they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.« less
Scanlan, Justin Newton; Hancock, Nicola; Honey, Anne
2018-03-01
There is a need for robust outcome measures for use in psychiatric services. Particularly lacking are self-rated recovery measures with evidence of sensitivity to change. This study was established to examine the convergent validity and sensitivity to change over time (responsiveness) of the Recovery Assessment Scale - Domains and Stages (RAS-DS), in comparison to level of unmet need as measured by the Camberwell Assessment of Need - Short Appraisal Scale (CANSAS). Convergent validity was examined through cross-sectional correlations between 540 CANSAS and RAS-DS scores collected on the same day for the same individuals. Sensitivity to change was examined using correlations between change scores in CANSAS and RAS-DS where both were collected on the same day and the two time points were separated by 90 days or more (n = 498). Results demonstrated moderate, significant cross-sectional correlations between CANSAS scores and RAS-DS total and domain scores and between change scores of both instruments. Results suggest that the RAS-DS is sensitive enough to detect change over time. Only moderate correlation between the RAS-DS and CANSAS suggests that, in the context of recovery-oriented service provision, it is important to measure self-reported recovery in addition to level of unmet needs. Copyright © 2018 Elsevier B.V. All rights reserved.
Liu, Hsin-Yun; Yang, Ching-Tzu; Wang, Yu-Nu; Hsu, Wen-Chuin; Huang, Tzu-Hsin; Lin, Yueh-E; Liu, Chin-Yi; Shyu, Yea-Ing L
2017-12-01
To examine the role of balancing competing needs in the relationship between caregiving demand and caregiving outcomes (caregivers' role strain and depressive symptoms). Caregivers who do not balance competing needs are more likely to experience negative caregiving outcomes, suggesting that balance mediates between caregiving demand and caregiving outcomes. Identifying a mediator of negative caregiving effects may help in developing tailored interventions for family caregivers of persons with dementia. A cross-sectional, correlational design. Data were collected from family caregivers' self-completed questionnaires between March 2013 - April 2014. A convenience sample of 120 family caregivers and care receivers with dementia was enrolled. We examined whether balance mediated the relationship between caregiving demand and caregiving outcomes (caregivers' role strain and depressive symptoms) by multiple regression analysis. To evaluate the significance of the indirect effect of caregiver balance, we used the Sobel test and Monte Carlo method, an alternative approach to testing mediation. Balancing competing needs completely mediated the association of caregiving demand with depressive symptoms and partially mediated the association of caregiving demand with role strain. Assessing caregivers' self-perceived sense of balance may help to identify caregivers at high risk for role strain and depressive symptoms. Interventions to enhance caregivers' perceived sense of balance between competing needs may provide a strategy for reducing the negative effects of caregiving. © 2017 John Wiley & Sons Ltd.
Socio-economic inequalities in health services utilization: a cross-sectional study.
Ranjbar Ezzatabadi, Mohammad; Khosravi, Ameneh; Bahrami, Mohammad Amin; Rafiei, Sima
2018-02-12
Purpose Developing country workers mainly face important challenges when examining equality in health services utilization among the population and identifying influential factors. The purpose of this paper us to: understand health service use among households with different socio-economic status in Isfahan province; and to investigate probable inequality determinants in service utilization. Design/methodology/approach Almost 1,040 households living in Isfahan province participated in this cross-sectional study in 2013. Data were collected by a questionnaire with three sections: demographic characteristics; socio-economic status; and health services utilization. The concentration index was applied to measure inequality. Analysts used STATA 11. Findings Economic status, educational level, insurance coverage and household gender were the most influential factors on health services utilization. Those with a high socio-economic level were more likely to demand and use such services; although self-medication patterns showed an opposite trend. Practical implications Female-headed families face with more difficulties in access to basic human needs including health. Supportive policies are needed to meet their demands. Originality/value The authors used principle component analysis to assess households' economic situation, which reduced the variables into a single index.
Ro, Young Sun; Shin, Sang Do; Jeong, Joongsik; Kim, Min Jung; Jung, Young Hee; Kamgno, Joseph; Alain, Etoundi Mballa Georges; Hollong, Bonaventure
2017-01-01
Objectives To assess the burden of emergent illnesses and emergency care system usage by Yaoundé residents and to evaluate unmet needs for emergency care and associated barriers. Design A cross-sectional study using a community-based survey. Setting Yaoundé, Cameroon. Participants All residents living in Yaoundé were selected as the target population to investigate the needs and usage of emergency care in Yaoundé. 14 households in every health area (47 in total) were selected using 2-stage sampling. Primary outcome measures Unmet needs for emergency care. Results Among the 3201 participants from 619 households who completed the survey, 1113 (34.8%) with median age of 22 experienced 1 or more emergency conditions in the previous year. Respondents who experienced emergency conditions used emergency units (7.0%), outpatient clinics (46.5%) or hospitalisation (13.0%), and in overall, 68.8% of them reported unmet needs for emergency care. The primary reasons for not seeking healthcare were economic issues (37.2%) and use of complementary medicine (22.2%). Young age (adjusted OR (95% CI) 1.80 (1.23 to 2.62)), rental housing (1.50 (1.11 to 2.03)) and moderate household income (0.60 (0.36 to 0.99)) were associated with unmet needs for emergency care. Conclusions Residents of Yaoundé had a high demand for emergency care, and high unmet needs were observed due to low emergency care usage. Development of a cost-effective, universal emergency care system is urgently needed in Cameroon. PMID:28167749
Dehghan, Reza; Mafimoradi, Shiva; Hadi, Mohammad
2015-01-01
Reviewing the human resources management literature shows an absence of attention given to the employee's benefits. Taking a look at functions of the Tehran University of Medical Sciences' wellbeing services system, it uncovers a gap between employees' real needs and what is delivered to meet their needs. So it requires an improved comprehensive system for delivering wellbeing services (financial, insurance, health care services, educational and training services, etc). Wellbeing need assessment can helps planners to identify vital needs of employee and response to them effectively. Moreover it can be used to evaluate the effectiveness of the current services which are delivered. Thus, the aim of this study is to assess wellbeing services of staffs working in TUMS to (1) evaluate the satisfactory rate of services which are delivered, and (2) exploring those wellbeing needs which were not fulfilled by the organization. Being a cross-sectional and analytic-descriptive survey including 98 responding participants, it is conducted by a questionnaire collecting employees' demographic information, their satisfactory rate of the implemented services, and determines unfulfilled wellbeing needs which were not already covered. Results indicated that services related to financial, educational, non-financial, insurance, occupational health and tourism/recreational services were the most satisfactory services successively. 'Staff's unwillingness to receive services' and 'poor announcement' (unawareness on the wellbeing services),' were found to be the most frequent reasons for not receiving the existing wellbeing services. To increase the satisfaction rate and responsiveness to the real needs of the staff, the current delivery system of wellbeing services in the TUMS should be redesigned by defining new wellbeing packages.
NASA Astrophysics Data System (ADS)
Szücs, T.; Kiss, G. G.; Gyürky, Gy.; Halász, Z.; Fülöp, Zs.; Rauscher, T.
2018-01-01
The stellar reaction rates of radiative α-capture reactions on heavy isotopes are of crucial importance for the γ process network calculations. These rates are usually derived from statistical model calculations, which need to be validated, but the experimental database is very scarce. This paper presents the results of α-induced reaction cross section measurements on iridium isotopes carried out at first close to the astrophysically relevant energy region. Thick target yields of 191Ir(α,γ)195Au, 191Ir(α,n)194Au, 193Ir(α,n)196mAu, 193Ir(α,n)196Au reactions have been measured with the activation technique between Eα = 13.4 MeV and 17 MeV. For the first time the thick target yield was determined with X-ray counting. This led to a previously unprecedented sensitivity. From the measured thick target yields, reaction cross sections are derived and compared with statistical model calculations. The recently suggested energy-dependent modification of the α + nucleus optical potential gives a good description of the experimental data.
Limit Theory for Panel Data Models with Cross Sectional Dependence and Sequential Exogeneity.
Kuersteiner, Guido M; Prucha, Ingmar R
2013-06-01
The paper derives a general Central Limit Theorem (CLT) and asymptotic distributions for sample moments related to panel data models with large n . The results allow for the data to be cross sectionally dependent, while at the same time allowing the regressors to be only sequentially rather than strictly exogenous. The setup is sufficiently general to accommodate situations where cross sectional dependence stems from spatial interactions and/or from the presence of common factors. The latter leads to the need for random norming. The limit theorem for sample moments is derived by showing that the moment conditions can be recast such that a martingale difference array central limit theorem can be applied. We prove such a central limit theorem by first extending results for stable convergence in Hall and Hedye (1980) to non-nested martingale arrays relevant for our applications. We illustrate our result by establishing a generalized estimation theory for GMM estimators of a fixed effect panel model without imposing i.i.d. or strict exogeneity conditions. We also discuss a class of Maximum Likelihood (ML) estimators that can be analyzed using our CLT.
Van Loon, Linda M A; Van de Ven, Monique O M; Van Doesum, Karin T M; Hosman, Clemens M H; Witteman, Cilia L M
2017-03-01
When adolescents live with a parent with mental illness, they often partly take over the parental role. Little is known about the consequences of this so-called parentification on the adolescents' internalizing and externalizing problems. This survey study examined this effect cross-sectionally and longitudinally in a sample of 118 adolescents living with a parent suffering from mental health problems. In addition, the study examined a possible indirect effect via perceived stress. Path analyses were used to examine the direct associations between parentification and problem behavior as well as the indirect relations via perceived stress. The results showed that parentification was associated with both internalizing and externalizing problems cross-sectionally, but it predicted only internalizing problems 1 year later. An indirect effect of parentification on adolescent internalizing and externalizing problems via perceived stress was found, albeit only cross-sectionally. These findings imply that parentification can be stressful for adolescents who live with a parent with mental health problems, and that a greater awareness of parentification is needed to prevent adolescents from developing internalizing problems. © 2015 Family Process Institute.
Lu, Yu; Van Ouytsel, Joris; Walrave, Michel; Ponnet, Koen; Temple, Jeff R
2018-06-01
The purpose of this study was to investigate the cross-sectional and temporal associations between cyber dating abuse victimization (CDAV) and mental health (i.e., anxiety, PTSD, and depression), and substance use (i.e., alcohol, cigarettes, marijuana and hard drugs). We used data from the 5th and 6th waves of an ongoing longitudinal study of ethnically diverse adolescents from seven public high schools in Texas, U.S. Participants were 641 adolescents (63.3% female) with a mean age of 19.1 years (SD = .79) at Wave 5. Analyses suggested that while CDAV was associated with mental health and substance use cross-sectionally, when examining over time, it was only associated with past year hard drug and past month marijuana use. Although long-term mental health effects of CDAV did not emerge in the current study, we identified a temporal link to marijuana and hard drugs, highlighting the need for prevention efforts to incorporate messages about substance use. Copyright © 2018 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Electron Impact Ionization of Atoms and Ions
NASA Astrophysics Data System (ADS)
Saha, B. C.; Basak, A. K.
2006-10-01
Electron impact ionization cross sections are at the heart of many active fields ranging from astro- to medical- physics. These applications require cross sections for a wide range of species as a function of projectile energies. This demand, however, is very hard to fulfill neither by experiments nor ab initio calculations. Various analytical and semi-classical models are commonly used to generate such a vast ionization cross sections. We recently applied a modified version [1] of the Bell et. al. equations [2] including both the ionic and relativistic corrections. We will show in this presentation how to generalize the much-needed MBELL parameters for treating the orbital quantum numbers nl dependency; comparing our results with experimental findings tests the accuracy of this procedure; very good agreements are obtained even in relativistic energies. Details will be presented at the meeting. [1] A. K. F. Haque, M. A. Uddin, A. K. Basak, K. R. Karim and B. C. Saha, Phys. Rev. A73, 052703 (2006). [2] K. L. Bell, H. B. Gilbody, J. G. Hughes, A. E. Kingston, and F. J. Smith, J. Phys. Chem. Ref. Data 12, 891 (1983).
NASA Technical Reports Server (NTRS)
Brucker, G. J.; Stassinopoulos, E. G.
1991-01-01
An analysis of the expected space radiation effects on the single event upset (SEU) properties of CMOS/bulk memories onboard the Combined Release and Radiation Effects Satellite (CRRES) is presented. Dose-imprint data from ground test irradiations of identical devices are applied to the predictions of cosmic-ray-induced space upset rates in the memories onboard the spacecraft. The calculations take into account the effect of total dose on the SEU sensitivity of the devices as the dose accumulates in orbit. Estimates of error rates, which involved an arbitrary selection of a single pair of threshold linear energy transfer (LET) and asymptotic cross-section values, were compared to the results of an integration over the cross-section curves versus LET. The integration gave lower upset rates than the use of the selected values of the SEU parameters. Since the integration approach is more accurate and eliminates the need for an arbitrary definition of threshold LET and asymptotic cross section, it is recommended for all error rate predictions where experimental sigma-versus-LET curves are available.
Skyrme forces and the fusion-fission dynamics of the 132Sn+64Ni→196Pt* reaction
NASA Astrophysics Data System (ADS)
Jain, Deepika; Kumar, Raj; Sharma, Manoj K.; Gupta, Raj K.
2012-02-01
The dependence of the fusion-fission process on Skyrme forces is studied by using the dynamical cluster-decay model (DCM) and the ℓ-summed extended-Wong model in the 132Sn+64Ni→196Pt* reaction, where the nuclear proximity potential is obtained by using the semiclassical extended Thomas-Fermi (ETF) approach in the Skyrme energy density formalism (SEDF) under the frozen density approximation. The DCM gives an excellent fit to the measured fusion evaporation residue (ER) and the fission cross sections below and above barrier energies, with ER data needing “barrier lowering” at below-barrier energies for each Skyrme force (an in-built property of the DCM). The fission cross sections show a contribution of quasifission (qf) at the above-barrier two or three highest energies, depending on the Skyrme force. Calculations are illustrated for three Skyrme forces, GSkI, SSk, and SIII. Another interesting result is that there is a change of fission mass distribution from a predominantly asymmetric one to a symmetric one with a decrease in the N/Z ratio of the compound nucleus, independent of the choice of nuclear interaction potential, which gives an opportunity to address the isospin effects in the Pt* nucleus. Within the ℓ-summed extended-Wong model we find that the GSkI and SSk forces fit the total fusion cross-section data exactly, whereas the SIII force needs “barrier modification” in order to fit the data at below-barrier energies. This happens because the isospin and neutron-proton asymmetry nature of GSkI and SSk forces is different from that of the SIII force, and because the center-of-mass energy Ec.m. dependence of the barrier height for the SIII force and that of Blocki [Ann. Phys. (NY)10.1016/0003-4916(77)90249-4 105, 427 (1977)] differs strongly (by a constant amount of ˜7 MeV) from those for GSKI and SSk forces. Note that, because of the associated preformation factor with each fragment, the DCM has the advantage of treating various decay processes separately, whereas the Wong model describes only the total fusion cross section, a sum of cross sections due to all contributing processes.
Photoeffect cross sections of some rare-earth elements at 145.4 keV
NASA Astrophysics Data System (ADS)
Umesh, T. K.; Ranganathaiah, C.; Sanjeevaiah, B.
1985-08-01
Total attenuation cross sections in the elements La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, and Er were derived from the measured total cross sections of their simple oxide compounds, by employing the mixture rule at 145.4-keV photon energy. The compound cross sections have been measured by performing transmission experiments in a good geometry setup. From the derived total cross sections of elements, photoeffect cross sections have been obtained by subtracting the theoretical scattering cross sections. A good agreement is observed between the present data of photoeffect cross sections and Scofield's theoretical data.
Mukherjee, Satarupa; Roy, Prithwish; Mitra, Souvik; Samanta, Moumita; Chatterjee, Sukanta
2013-01-01
Objective The neonatal mortality rate (NMR) continues to remain quite high, one important cause being preterm deliveries. The main obstacle in the pathway towards decreasing NMR is identification of babies in need of extra care. To analyze the utility of newborn foot length as a proxy measure for birth weight and gestational age. Methods A cross-sectional study done in a hospital of eastern India with 351 babies during 4 months. Right foot length of each recorded using a plastic, stiff ruler. Findings 48.1% babies were preterm, 51.8% low birth weight (LBW) and 33.3% very low birth weight (VLBW). Foot length less than 7.75 cm has 92.3% sensitivity and 86.3% specificity for identification of preterm neonates. For identification of LBW babies (<2500 gm) a foot length less than 7.85cm has 100% sensitivity and 95.3% specificity. Foot length less than 6.85 cm has 100% sensitivity and 94.9% specifity for identification of VLBW babies (<1500 gm). Conclusion Foot length may be used in the identification of LBW and preterm babies who are in need of extra care. PMID:24800008
Research on Sociocultural Influences on Motivation and Learning, Volume 1.
ERIC Educational Resources Information Center
McInerney, Dennis M., Ed.; Van Etten, Shawn, Ed.
This collection of papers explores sociocultural influences on motivation and learning across a broad range of settings and content areas. There are 16 papers in five sections. "Introduction" includes: (1) "Modern Education Needs Cross-Cultural Psychology" (Harry Triandis). Part 1, "The Motivation Context," includes:…
The challenges of female adolescents' health needs.
Shahhosseini, Z; Simbar, M; Ramezankhani, A; Alavi Majd, H; Moslemizadeh, Narges
2013-12-01
Due to adolescents' future crucial roles, their health needs should be included in the national health system policy. In this cross-sectional study 2010 female adolescents were recruited from randomly selected schools in Iran. To obtain their health needs, the participants completed a self-administrated questionnaire. It was revealed that emotional needs were the most important health needs of adolescents. Furthermore, there was a meaningful relationship between health needs' score with the adolescents' age and their mothers' education level. Finally, the mean score of health needs was significantly higher in urban adolescents. Therefore, it is suggested that adolescents' emotional health needs to be paid attention; otherwise irrecoverable serious problems may occur in the next generation's health.
Equity in access to health care in a rural population in Malaysia: A cross-sectional study.
Lim, Ka Keat; Sivasampu, Sheamini; Mahmud, Fatihah
2017-04-01
To examine the extent of equity in access to health care, their determinants and reasons of unmet need of a rural population in Malaysia. Exploratory cross-sectional survey administered by trained interviewers among participants of a health screening program. A rural plantation estate in the West Coast of Peninsular Malaysia. One hundred and thirty out of 142 adults above 18 years old who attended the program. Percentages of respondents reporting realised access and unmet need to health care, determinants of both access indicators and reasons for unmet need. Realised access associated with need but not predisposing or enabling factors and unmet need not associated with any variables were considered equitable. A total of 88 (67.7%) respondents had visited a doctor (realised access) in the past 6 months and 24.8% (n = 31) experienced unmet need in the past 12 months. Using logistic regression, realised access was associated with presence of chronic disease (OR 6.97, P < 0.001), whereas unmet need was associated with low education level (OR 6.50, P < 0.05), 'poor' or 'fair' self-assessed health status (OR 6.03, P < 0.05) and highest income group (> RM 2000 per month) (OR 51.27, P < 0.05). Personal choice (67.7%) was more commonly expressed than barriers (54.8%) as reasons for unmet need. The study found equity in realised access and inequity in unmet need among the rural population, the latter associated with education level, subjective health status and income. Despite not being generalisable, the findings highlight the need for a national level study on equity in access before the country reforms its health system. © 2016 National Rural Health Alliance Inc.
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.
Lee, Bokim; Jung, Hye-Sun
2012-01-01
The researchers conducted a cross-sectional survey to determine the relationship between handling heavy items during pregnancy and spontaneous abortion among working women in South Korea. One thousand working women were selected from a database of those eligible for maternity benefits under the National Employment Insurance Plan. Study results showed that handling heavy items during pregnancy was associated with an increased risk of spontaneous abortion after adjusting for general characteristics of the participants and their work environment. A collective effort is needed on the parts of employers, employees, occupational health nurses, and the government to protect working women from lifting heavy items while pregnant. Copyright 2012, SLACK Incorporated.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harper, J.A.; Abel, K.D.; Piotrowski, R.G.
Ten cross sections were completed and drafted, and blueline copies were sent to DOE, Morgantown, WV, for review. These cross sections were used as the basis with which all other logs in the study area were correlated. The data has been encoded from 228 logs that were used. Two isopach, 2 structure contour, and 3 lithofacies maps have been completed and are awaiting drafting. A production and show map has been drafted and blueline copies were sent to DOE, Morgantown, WV, for review. The schedule of work was delayed due to the state budget problems the need to correct workmore » previously completed and sent to DOE, Morgantown, WV, and lack of a reproduction contract.« less
Different methods of image segmentation in the process of meat marbling evaluation
NASA Astrophysics Data System (ADS)
Ludwiczak, A.; Ślósarz, P.; Lisiak, D.; Przybylak, A.; Boniecki, P.; Stanisz, M.; Koszela, K.; Zaborowicz, M.; Przybył, K.; Wojcieszak, D.; Janczak, D.; Bykowska, M.
2015-07-01
The level of marbling in meat assessment based on digital images is very popular, as computer vision tools are becoming more and more advanced. However considering muscle cross sections as the data source for marbling level evaluation, there are still a few problems to cope with. There is a need for an accurate method which would facilitate this evaluation procedure and increase its accuracy. The presented research was conducted in order to compare the effect of different image segmentation tools considering their usefulness in meat marbling evaluation on the muscle anatomical cross - sections. However this study is considered to be an initial trial in the presented field of research and an introduction to ultrasonic images processing and analysis.
Hutchens, Amy; Soltero, Erica G; Barquera, Simón; Lévesque, Lucie; Jauregui, Edtna; López Y Taylor, Juan; Lee, Rebecca E
2016-01-01
This cross sectional study aims to determine the effects of gender and parental perception of safety at school on children's physical activity (PA) levels. Parents of school aged Mexican children residing in Guadalajara, Mexico City, and Puerto Vallarta, completed surveys about their children's PA measures. The physical activity indicators were evaluated using linear and logistical regression models. Analysis did not indicate that gender moderated the relationship between parental perception of safety and PA measures, but significant gender issues exist with girls participating less than boys in the three measures of PA in this study (p<0.001). Results suggest the need for additional interventions promoting physical activity in girls in Mexico.
NASA Astrophysics Data System (ADS)
Lique, François; Jiménez-Serra, Izaskun; Viti, Serena; Marinakis, Sarantos
2018-01-01
We present the first ab initio potential energy surfaces (PESs) for the PO(X2Π)-He van der Waals system. The PESs were obtained using the open-shell partially spin-restricted coupled cluster approach with single, double and perturbative triple excitations [UCCSD(T)]. The augmented correlation-consistent polarized valence triple-zeta (aug-cc-pVTZ) basis set was employed supplemented by mid-bond functions. Integral and differential cross sections for the rotational excitation in PO-He collisions were calculated using the new PES and compared with results in similar systems. Finally, our work presents the first hyperfine-resolved cross sections for this system that are needed for accurate modelling in astrophysical environments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peters, William A; Smith, Michael Scott; Clement, Ryan
2013-10-01
The goal of this proposal is to enable neutron detection for precision Non-Destructive Assays (NDAs) of actinide-fluoride samples. Neutrons are continuously generated from a UFx matrix in a container or sample as a result of the interaction of alpha particles from uranium-decay α particles with fluorine nuclei in the matrix. Neutrons from 19F(α,n)22Na were once considered a poorly characterized background for assays of UFx samples via 238U spontaneous fission neutron detection [SMI2010B]. However, the yield of decay-α-driven neutrons is critical for 234,235U LEU and HEU assays, as it can used to determine both the total amount of uranium and themore » enrichment [BER2010]. This approach can be extremely valuable in a variety of safeguard applications, such as cylinder monitoring in underground uranium storage facilities, nuclear criticality safety studies, nuclear materials accounting, and other nonproliferation applications. The success of neutron-based assays critically depends on an accurate knowledge of the cross section of the (α,n) reaction that generates the neutrons. The 40% uncertainty in the 19F(α,n)22Na cross section currently limits the precision of such assays, and has been identified as a key factor in preventing accurate enrichment determinations [CRO2003]. The need for higher quality cross section data for (α,n) reactions has been a recurring conclusion in reviews of the nuclear data needs to support safeguards. The overarching goal of this project is to enable neutron detection to be used for precision Non- Destructive Assays (NDAs) of actinide-fluoride samples. This will significantly advance safeguards verification at existing declared facilities, nuclear materials accounting, process control, nuclear criticality safety monitoring, and a variety of other nonproliferation applications. To reach this goal, Idaho National Laboratory (INL), in partnership with Oak Ridge National Laboratory (ORNL), Rutgers University (RU), and the University of Notre Dame (UND), will focus on three specific items: (1) making a precision (better than 10 %) determination of the absolute cross section of the 19F(α,n)22Na reaction as a function of energy; (2) determining the spectrum of neutrons and γ-rays emitted from 19F(α,n)22Na over an energy range pertinent to NDA; and (3) performing simulations with this new cross section to extract the neutron yield (neutrons/gram/second) and resulting neutron- and gamma ray-spectra when α particles interact with fluorine nuclei in actinide samples, to aid in the design and reduce uncertainty of future NDA measurements and simulations.« less
Stiffness Characteristics of Composite Rotor Blades With Elastic Couplings
NASA Technical Reports Server (NTRS)
Piatak, David J.; Nixon, Mark W.; Kosmatka, John B.
1997-01-01
Recent studies on rotor aeroelastic response and stability have shown the beneficial effects of incorporating elastic couplings in composite rotor blades. However, none of these studies have clearly identified elastic coupling limits and the effects of elastic couplings on classical beam stiffnesses of representative rotor blades. Knowledge of these limits and effects would greatly enhance future aeroelastic studies involving composite rotor blades. The present study addresses these voids and provides a preliminary design database for investigators who may wish to study the effects of elastic couplings on representative blade designs. The results of the present study should provide a basis for estimating the potential benefits associated with incorporating elastic couplings without the need for first designing a blade cross section and then performing a cross-section analysis to obtain the required beam section properties as is customary in the usual one-dimensional beam-type approach.
Berenbrock, Charles E.
2015-01-01
The effects of reduced cross-sectional data points on steady-flow profiles were also determined. Thirty-five cross sections of the original steady-flow model of the Kootenai River were used. These two methods were tested for all cross sections with each cross section resolution reduced to 10, 20 and 30 data points, that is, six tests were completed for each of the thirty-five cross sections. Generally, differences from the original water-surface elevation were smaller as the number of data points in reduced cross sections increased, but this was not always the case, especially in the braided reach. Differences were smaller for reduced cross sections developed by the genetic algorithm method than the standard algorithm method.
Understanding Broadscale Wildfire Risks in a Human-Dominated Landscape
Jeffrey P. Prestemon; John M. Pye; David T. Butry; Thomas P. Holmes; D. Evan Mercer
2002-01-01
Broadscale statistical evaluations of wildfire incidence can answer policy relevant questions about the effectiveness of microlevel vegetation management and can identify subjects needing further study. A dynamic time series cross-sectional model was used to evaluate the statistical links between forest wildfire and vegetation management, human land use, and climatic...
Cross-Sectional Predictors of "Risk" for School Failure
ERIC Educational Resources Information Center
Petridou, Alexandra; Karagiorgi, Yiasemina
2016-01-01
Since school failure has detrimental effects on students and on society, education policy needs to address students "at risk," and support them to reach their potential. This study used data from the longitudinal national Programme for Functional Literacy (PfL) conducted in Cyprus to identify students "at risk" and aimed to…
Public vs. Private: Time for an Honest Discussion That Could Benefit All Schools.
ERIC Educational Resources Information Center
DeBlois, Robert
1997-01-01
Notes there are many worthwhile educational programs serving a cross-section of students featuring elements of both public and private sectors. Reform initiatives recognize that schools need to form real partnerships with local businesses, community-based organizations, universities, and other organizations. Maintains that although Education…
Racial and Socioeconomic Disparities in Nutrition Behaviors: Targeted Interventions Needed
ERIC Educational Resources Information Center
Fahlman, Mariane M.; McCaughtry, Nate; Martin, Jeffrey; Shen, Bo
2010-01-01
Objective: To compare dietary knowledge, behaviors and self-efficacy of black middle school students of low socioeconomic status with their white counterparts of higher socioeconomic status. Design: Cross-sectional, school-based survey. Setting: Large metropolitan area in the United States. Participants: Middle school students (1,208 of low…
Aydoğan, Cihan
2018-05-22
To investigate the effects of personality traits to moderate the relationships between orthodontic treatment need and oral health-related quality of life (OHRQoL) in adolescents. A cross-sectional study was performed that included 230 subjects (125 girls and 105 boys) aged 11-14 years. Orthodontic treatment need was measured using the Index of Complexity, Outcome and Need (ICON). The Child Perceptions Questionnaire, the Basic Personality Traits Inventory (BPTI), and the Revised Life Orientation Test were used to assess the OHRQoL, basic personality dimensions, and dispositional optimism respectively. Potential moderation effects were evaluated with Spearman's correlations and multiple regression analyses. There were weak correlations between orthodontic treatment need and quality of life with social and emotional well-being dimensions ( r = 0.238, r = 0.296 and r = 0.209). A moderating effect of extraversion was observed in the relationship between orthodontic treatment need and OHRQoL, emotional well-being, and social well-being (SWB) (Δ R 2 = 0.03, Δ R 2 = 0.02, and Δ R 2 = 0.04, respectively). Openness to experience affected relationships between orthodontic treatment need and OHRQoL, and emotional well-being (EWB) (Δ R 2 = 0.03 and Δ R 2 = 0.04, respectively). In children with higher extraversion, the increase in ICON scores resulted in less increase in CPQ total, EWB, and SWB scores. In children with higher openness to experience, the increase influenced CPQ total and EWB scores similarly. The relationship between orthodontic treatment need and quality of life is moderated by personality traits. Early adolescents with higher extraversion and openness to experience are less affected by increased orthodontic treatment need.
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.
Study of BenW (n = 1-12) clusters: An electron collision perspective
NASA Astrophysics Data System (ADS)
Modak, Paresh; Kaur, Jaspreet; Antony, Bobby
2017-08-01
This article explores electron scattering cross sections by Beryllium-Tungsten clusters (BenW). Beryllium and tungsten are important elements for plasma facing wall components, especially for the deuterium/tritium phase of ITER and in the recently installed JET. The present study focuses on different electron impact interactions in terms of elastic cross section (Qel), inelastic cross section (Qinel), ionization cross section (Qion), and momentum transfer cross section (Qmtcs) for the first twelve clusters belonging to the BenW family. It also predicts the evolution of the cross section with the size of the cluster. These cross sections are used as an input to model processes in plasma. The ionization cross section presented here is compared with the available reported data. This is the first comprehensive report on cross section data for all the above-mentioned scattering channels, to the best of our knowledge. Such broad analysis of cross section data gives vital insight into the study of local chemistry of electron interactions with BenW (n = 1-12) clusters in plasma.
Averaging cross section data so we can fit it
DOE Office of Scientific and Technical Information (OSTI.GOV)
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).
New cross sections for H on H2 collisional transitions
NASA Astrophysics Data System (ADS)
Zou, Qianxia
2011-12-01
The cross section for H on H2 collisions is important for astrophysics as well as our understanding of the simple chemical systems. This is the simplest atom-molecule cross section. With a new H3 potential surface by Mielke et al., we have modified the ABC code by Skouteris, Castillo and Manolopoulos to calculate new cross sections. These cross sections are compared to previous cross section calculations.
A computer program for analyzing channel geometry
Regan, R.S.; Schaffranek, R.W.
1985-01-01
The Channel Geometry Analysis Program (CGAP) provides the capability to process, analyze, and format cross-sectional data for input to flow/transport simulation models or other computational programs. CGAP allows for a variety of cross-sectional data input formats through use of variable format specification. The program accepts data from various computer media and provides for modification of machine-stored parameter values. CGAP has been devised to provide a rapid and efficient means of computing and analyzing the physical properties of an open-channel reach defined by a sequence of cross sections. CGAP 's 16 options provide a wide range of methods by which to analyze and depict a channel reach and its individual cross-sectional properties. The primary function of the program is to compute the area, width, wetted perimeter, and hydraulic radius of cross sections at successive increments of water surface elevation (stage) from data that consist of coordinate pairs of cross-channel distances and land surface or channel bottom elevations. Longitudinal rates-of-change of cross-sectional properties are also computed, as are the mean properties of a channel reach. Output products include tabular lists of cross-sectional area, channel width, wetted perimeter, hydraulic radius, average depth, and cross-sectional symmetry computed as functions of stage; plots of cross sections; plots of cross-sectional area and (or) channel width as functions of stage; tabular lists of cross-sectional area and channel width computed as functions of stage for subdivisions of a cross section; plots of cross sections in isometric projection; and plots of cross-sectional area at a fixed stage as a function of longitudinal distance along an open-channel reach. A Command Procedure Language program and Job Control Language procedure exist to facilitate program execution on the U.S. Geological Survey Prime and Amdahl computer systems respectively. (Lantz-PTT)
Association between vertebral cross-sectional area and lumbar lordosis angle in adolescents
Aggabao, Patricia C.; Poorghasamians, Ervin; Chavez, Thomas A.
2017-01-01
Lumbar lordosis (LL) is more prominent in women than in men, but the mechanisms responsible for this discrepancy are poorly defined. A recent study indicates that newborn girls have smaller vertebral cross-sectional area (CSA) when compared to boys—a difference that persists throughout life and is independent of body size. We determined the relations between vertebral cross-sectional area (CSA) and LL angle and whether sex differences in lumbar lordosis are related to sex differences in vertebral CSA. Using multi-planar magnetic resonance imaging (MRI), we measured vertebral cross-sectional area (CSA) and vertebral height of the spine of 40 healthy boys and 40 girls, ages 9–13 years. Measures of the CSA of the lumbar vertebrae significantly differed between sexes (9.38 ± 1.46 vs. 7.93 ± 0.69 in boys and girls, respectively; P < 0.0001), while the degree of LL was significantly greater in girls than in boys (23.7 ± 6.1 vs. 27.6 ± 8.0 in boys and girls, respectively; P = 0.02). When all subjects were analyzed together, values for LL angle were negatively correlated to vertebral CSA (r = -0.47; P < 0.0001); this was also true when boys and girls were analyzed separately. Multivariate regression analysis indicated that vertebral CSA was independently associated with LL, even after accounting for sex, age, height or vertebral height, and weight. Similar negative relations were present when thoracic vertebrae were analyzed (Model P < 0.0001, R2 = 0.37, thoracic vertebral CSA slope P < 0.0001), suggesting that deficient vertebral cross-sectional dimensions are not merely the consequence of the anterior lumbar curvature. We conclude that vertebral CSA is negatively associated with LL, and that the greater degree of LL in females could, at least in part, be due to smaller vertebral cross-sectional dimensions. Studies are needed to examine the potential relations between vertebral CSA and spinal conditions known to be associated with increased LL, such as spondylolysis and spondylolisthesis. PMID:28245271
Almont, Thierry; Delannes, Martine; Ducassou, Anne; Corman, André; Bondil, Pierre; Moyal, Elizabeth; Schover, Leslie; Huyghe, Eric
2017-04-01
Providing early and better care in onco-sexuality and a better understanding of the sexual health care needs of patients before they start treatment is required. To assess sexual quality of life and need for sexology care of patients when they are starting radiotherapy. We performed a cross-sectional study of adult patients with cancer admitted for radiotherapy treatment in a regional comprehensive cancer center. We selected all consecutive adult patients scheduled to start radiotherapy within a 3-month period and excluded patients who could not complete the questionnaires. Patients were asked to complete the Sexual Quality of Life Questionnaire (SQoL) and a needs-assessment questionnaire. Total score on the SQoL and willingness (yes or no) to get help for a sexual problem. The study sample was composed of 77 men and 123 women. The average SQoL scores were 68.4 ± 20.9 and 47.1 ± 13.0 for men and women, respectively (P < .001). Of sexually active patients, 58% had decreased frequency of intercourse or had completely stopped sexual activity after their cancer diagnosis. Half the participants wanted care for their sexual concerns. The proportion desiring specific types of care varied from 28.5% (couple counseling) to 54.5% (sexual physician) with variation by sex or type of cancer. Furthermore, 11.5% of participants declared their willingness to join support groups. Early interventions before radiotherapy could improve sexual quality of life, particularly in women. Strengths are the SQoL validated in men and women, the original window for assessment, and the study location. Limitations are the monocentric design, the potential recall bias for data before cancer diagnosis, and the fact that some patients had treatments before radiotherapy. Our data suggest the need to examine the sexual health trajectory in a prospective fashion from diagnosis to survivorship. Almont T, Delannes M, Ducasson A, et al. Sexual Quality of Life and Needs for Sexology Care of Cancer Patients Admitted for Radiotherapy: A 3-Month Cross-Sectional Study in a Regional Comprehensive Reference Cancer Center. J Sex Med 2017;14:566-576. Copyright © 2017 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.
Low-voltage cross-sectional EBIC for characterisation of GaN-based light emitting devices.
Moldovan, Grigore; Kazemian, Payam; Edwards, Paul R; Ong, Vincent K S; Kurniawan, Oka; Humphreys, Colin J
2007-01-01
Electron beam induced current (EBIC) characterisation can provide detailed information on the influence of crystalline defects on the diffusion and recombination of minority carriers in semiconductors. New developments are required for GaN light emitting devices, which need a cross-sectional approach to provide access to their complex multi-layered structures. A sample preparation approach based on low-voltage Ar ion milling is proposed here and shown to produce a flat cross-section with very limited surface recombination, which enables low-voltage high resolution EBIC characterisation. Dark defects are observed in EBIC images and correlation with cathodoluminescence images identify them as threading dislocations. Emphasis is placed on one-dimensional quantification which is used to show that junction delineation with very good spatial resolution can be achieved, revealing significant roughening of this GaN p-n junction. Furthermore, longer minority carrier diffusion lengths along the c-axis are found at dislocation sites, in both p-GaN and the multi-quantum well (MQW) region. This is attributed to gettering of point defects at threading dislocations in p-GaN and higher escape rate from quantum wells at dislocation sites in the MQW region, respectively. These developments show considerable promise for the use of low-voltage cross-sectional EBIC in the characterisation of point and extended defects in GaN-based devices and it is suggested that this technique will be particularly useful for degradation analysis.
On the feasibility to perform integral transmission experiments in the GELINA target hall at IRMM
NASA Astrophysics Data System (ADS)
Leconte, Pierre; Jean, Cyrille De Saint; Geslot, Benoit; Plompen, Arjan; Belloni, Francesca; Nyman, Markus
2017-09-01
Shielding experiments are relevant to validate elastic and inelastic scattering cross sections in the fast energy range. In this paper, we are focusing on the possibility to use the pulsed white neutron time-of-flight facility GELINA to perform this kind of measurement. Several issues need to be addressed: neutron source intensity, room return effect, distance of the materials to be irradiated from the source, and the sensitivity of various reaction rate distributions through the material to different input cross sections. MCNP6 and TRIPOLI4 calculations of the outgoing neutron spectrum are compared, based on electron/positron/gamma/neutron simulations. A first guess of an integral transmission experiment through a 238U slab is considered. It shows that a 10 cm thickness of uranium is sufficient to reach a high sensitivity to the 238U inelastic scattering cross section in the [2-5 MeV] energy range, with small contributions from elastic and fission cross sections. This experiment would contribute to reduce the uncertainty on this nuclear data, which has a significant impact on the power distribution in large commercial reactors. Other materials that would be relevant for the ASTRID 4th generation prototype reactor are also tested, showing that a sufficient sensitivity to nuclear data would be obtained by using a 50 to 100cm thick slab of side 60x60cm. This study concludes on the feasibility and interest of such experiments in the target hall of the GELINA facility.
Multistrand superconductor cable
Borden, A.R.
1984-03-08
Improved multistrand Rutherford-type superconductor cable is produced by using strands which are preformed, prior to being wound into the cable, so that each strand has a variable cross section, with successive portions having a substantially round cross section, a transitional oval cross section, a rectangular cross section, a transitional oval cross section, a round cross section and so forth, in repetitive cycles along the length of the strand. The cable is wound and flattened so that the portions of rectangular cross section extend across the two flat sides of the cable at the strand angle. The portions of round cross section are bent at the edges of the flattened cable, so as to extend between the two flat sides. The rectangular portions of the strands slide easil
Social Roles, Basic Need Satisfaction, and Psychological Health: The Central Role of Competence
Talley, Amelia E.; Kocum, Lucie; Schlegel, Rebecca J.; Molix, Lisa; Bettencourt, B. Ann
2016-01-01
The authors propose that competence need fulfillment within valued role domains (i.e., spouse, parent, worker) will account, in part, for associations between autonomy and relatedness need fulfillment and psychological health. Testing these assertions in cross-sectional and longitudinal surveys of women in two independent community samples, the findings are the first to formally examine whether the satisfaction of competence needs within social roles accounts for associations between other types of need satisfaction and affective outcomes as well as depressive symptomology. Evidence supporting the hypothesis was stronger when examining individuals’ affective health as compared to their depressive symptoms. Implications of the findings are discussed with regard to need fulfillment within social roles. PMID:22215698
Social roles, basic need satisfaction, and psychological health: the central role of competence.
Talley, Amelia E; Kocum, Lucie; Schlegel, Rebecca J; Molix, Lisa; Bettencourt, B Ann
2012-02-01
The authors propose that competence need fulfillment within valued role domains (i.e., spouse, parent, worker) will account, in part, for associations between autonomy and relatedness need fulfillment and psychological health. Testing these assertions in cross-sectional and longitudinal surveys of women in two independent community samples, the findings are the first to formally examine whether the satisfaction of competence needs within social roles accounts for associations between other types of need satisfaction and affective outcomes as well as depressive symptomology. Evidence supporting the hypothesis was stronger when examining individuals' affective health as compared to their depressive symptoms. Implications of the findings are discussed with regard to need fulfillment within social roles.
Dehghan, Reza; Mafimoradi, Shiva; Hadi, Mohammad
2015-01-01
Background: Reviewing the human resources management literature shows an absence of attention given to the employee's benefits. Taking a look at functions of the Tehran University of Medical Sciences’ wellbeing services system, it uncovers a gap between employees’ real needs and what is delivered to meet their needs. So it requires an improved comprehensive system for delivering wellbeing services (financial, insurance, health care services, educational and training services, etc). Wellbeing need assessment can helps planners to identify vital needs of employee and response to them effectively. Moreover it can be used to evaluate the effectiveness of the current services which are delivered. Thus, the aim of this study is to assess wellbeing services of staffs working in TUMS to (1) evaluate the satisfactory rate of services which are delivered, and (2) exploring those wellbeing needs which were not fulfilled by the organization. Material and Methods: Being a cross-sectional and analytic-descriptive survey including 98 responding participants, it is conducted by a questionnaire collecting employees’ demographic information, their satisfactory rate of the implemented services, and determines unfulfilled wellbeing needs which were not already covered. Result: Results indicated that services related to financial, educational, non-financial, insurance, occupational health and tourism/recreational services were the most satisfactory services successively. ‘Staff's unwillingness to receive services’ and ‘poor announcement’ (unawareness on the wellbeing services),’ were found to be the most frequent reasons for not receiving the existing wellbeing services. Conclusion: To increase the satisfaction rate and responsiveness to the real needs of the staff, the current delivery system of wellbeing services in the TUMS should be redesigned by defining new wellbeing packages. PMID:25767818
Ro, Young Sun; Shin, Sang Do; Jeong, Joongsik; Kim, Min Jung; Jung, Young Hee; Kamgno, Joseph; Alain, Etoundi Mballa Georges; Hollong, Bonaventure
2017-02-06
To assess the burden of emergent illnesses and emergency care system usage by Yaoundé residents and to evaluate unmet needs for emergency care and associated barriers. A cross-sectional study using a community-based survey. Yaoundé, Cameroon. All residents living in Yaoundé were selected as the target population to investigate the needs and usage of emergency care in Yaoundé. 14 households in every health area (47 in total) were selected using 2-stage sampling. Unmet needs for emergency care. Among the 3201 participants from 619 households who completed the survey, 1113 (34.8%) with median age of 22 experienced 1 or more emergency conditions in the previous year. Respondents who experienced emergency conditions used emergency units (7.0%), outpatient clinics (46.5%) or hospitalisation (13.0%), and in overall, 68.8% of them reported unmet needs for emergency care. The primary reasons for not seeking healthcare were economic issues (37.2%) and use of complementary medicine (22.2%). Young age (adjusted OR (95% CI) 1.80 (1.23 to 2.62)), rental housing (1.50 (1.11 to 2.03)) and moderate household income (0.60 (0.36 to 0.99)) were associated with unmet needs for emergency care. Residents of Yaoundé had a high demand for emergency care, and high unmet needs were observed due to low emergency care usage. Development of a cost-effective, universal emergency care system is urgently needed in Cameroon. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.
Arvieu, Jean-Jacques; Aegerter, Philippe; Robine, Jean-Marie; Ankri, Joël
2014-01-01
Background: Unmet health care needs are associated with negative health outcomes, yet there is a paucity of data on this problem among older people. Objective: To identify unmet health care needs and associated factors among older people in France. Methods: This is a cross-sectional population study of people aged 70 years or older in which 2350 respondents were interviewed in 2008–10. During a standardized interview, a nurse examined health problems, functional abilities and use of health care resources. Unmet health care needs were defined as situations in which a participant needed health care and did not receive it. Results: The mean age was 83.2 ± 7.4 years. Almost all participants reporting a chronic disease (98.6%) had consulted a physician in the previous 6 months. Unmet health care needs were found in 23.0% of the sample and mainly consisted of lack of dental care (prevalence of 17.7%), followed by lack of management of visual or hearing impairments (prevalence of 4.4% and 3.1%, respectively). Age was the main factor associated with unmet health care needs [compared with people aged 70–79: odds ratio80–89 years = 2.26 (1.70–3.03), odds ratio90 years and over = 3.85 (2.71–5.45)]. Other associated factors were regular smoking, homebound status, poor socioeconomic conditions, depression, limitations in instrumental activities of daily living and low medical density. Conclusion: Unmet health care needs affect almost one-quarter of older people in France. Efforts should be made to improve oral health and develop home care, especially for the oldest-olds. PMID:24287029
Moreland-Russell, Sarah; Cyr, Julianne; Benson, Peter; Colditz, Graham; Pulley, Deren; Barnoya, Joaquin
2012-01-01
This cross-sectional study provides information about secondhand smoke exposure across the St. Louis metro area and perceptions and attitudes about tobacco and health within the local hospitality industry. Results from this study support the need for passage and implementation of comprehensive smoke-free laws throughout Missouri, particularly in St. Louis City and County where efforts to pass comprehensive smoke-free laws have been unsuccessful.
Point prevalence of mental disorder in unconvicted male prisoners in England and Wales.
Brooke, D.; Taylor, C.; Gunn, J.; Maden, A.
1996-01-01
OBJECTIVES: To determine prevalence of mental disorder among male unconvicted prisoners and to assess the treatment needs of this population. DESIGN: Semi-structured interview and case note review of randomly selected cross section of male remand population. Non-attenders were replaced by the next name on prison roll. SETTING: Three young offenders' institutions and 13 adult men's prisons. SUBJECTS: 750 prisoners, representing 9.4% cross sectional sample of male unconvicted population. MAIN OUTCOME MEASURES: Prevalence of ICD-10 diagnoses of mental disorder, and associated treatment needs. RESULTS: Psychiatric disorder was diagnosed in 469 (63%) inmates. The main diagnoses were: substance misuse, 285 (38%); neurotic illness, 192 (26%); personality disorder, 84 (11%); psychosis, 36 (5%); other and uncertain, 36 (0.5%). Subjects could have more than one diagnosis. The average refusal rate was 18%. In total 414 inmates (55%) were judged to have an immediate treatment need: transfer to an NHS bed, 64 (9%); treatment by prison health care services, 131 (17%); motivational interviewing for substance misuse, 115 (15%); and therapeutic community placement, 104 (14%). CONCLUSIONS: Mental disorder was common among male unconvicted prisoners. Psychosis was present at four or five times the level found in the general population. Extrapolation of our results suggests that remand population as a whole probably contains about 680 men who need transfer to hospital for psychiatric treatment, including about 380 prisoners with serious mental illness. PMID:8978228
Milne, Nikki; Choy, Nancy Low; Leong, Gary M; Hughes, Roger; Hing, Wayne
2016-01-01
This study explored current physiotherapy practice trends for management of children who are overweight or obese. The professional needs of physiotherapists working with this population were also assessed, including the perceived need for physiotherapy clinical guidelines for prevention and management of children with obesity. A cross-sectional survey design was used, with questionnaires purposefully distributed through 13 key physiotherapy services throughout Australia. Snowball sampling resulted in completed questionnaires from 64 physiotherapists who provided services to children. Half (n=33, 52%) of respondents provided services specifically to overweight or obese children. Of those providing services, one-quarter had prior training specific to working with this population. Most used multi-disciplinary models (n=16, 76%) and provided under 5h of obesity-related services each week (n=29, 88%). Half (n=16, 49%) used body mass index as an outcome measure but more (n=25, 76%) used bodyweight. Only 14 (42%) assessed motor skills. The majority of respondents (n=57, 89%) indicated a need for physiotherapy guidelines to best manage overweight and obese children. Professional development priorities included: 'Educating children and families', 'Assessment methods' and 'Exercise prescription' for overweight and obese children. This data provides workforce intelligence to guide future professional training and inform development of clinical guidelines for physiotherapists in prevention and management of children with obesity and related chronic disease.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Favorite, Jeffrey A.
SENSMG is a tool for computing first-order sensitivities of neutron reaction rates, reaction-rate ratios, leakage, k eff, and α using the PARTISN multigroup discrete-ordinates code. SENSMG computes sensitivities to all of the transport cross sections and data (total, fission, nu, chi, and all scattering moments), two edit cross sections (absorption and capture), and the density for every isotope and energy group. It also computes sensitivities to the mass density for every material and derivatives with respect to all interface locations. The tool can be used for one-dimensional spherical (r) and two-dimensional cylindrical (r-z) geometries. The tool can be used formore » fixed-source and eigenvalue problems. The tool implements Generalized Perturbation Theory (GPT) as discussed by Williams and Stacey. Section II of this report describes the theory behind adjoint-based sensitivities, gives the equations that SENSMG solves, and defines the sensitivities that are output. Section III describes the user interface, including the input file and command line options. Section IV describes the output. Section V gives some notes about the coding that may be of interest. Section VI discusses verification, which is ongoing. Section VII lists needs and ideas for future work. Appendix A lists all of the input files whose results are presented in Sec. VI.« less
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.
Kasai, Takehiro; Ishiguro, Naoki; Matsui, Yasumoto; Harada, Atsushi; Takemura, Marie; Yuki, Atsumu; Kato, Yuki; Otsuka, Rei; Ando, Fujiko; Shimokata, Hiroshi
2015-06-01
Sex- and age-related differences in mid-thigh composition and muscle quality remain unclear. The present study aimed to clarify these differences using computed tomography in middle-aged and elderly Japanese. A total of 2310 participants (age 40-89 years), who were randomly selected from the local residents, underwent computed tomography examination of the right mid-thigh. Thigh circumference and cross-sectional areas of the thigh, muscle, quadriceps, non-quadriceps, fat, and bone were measured. Knee extension strength and muscle quality index (knee extension strength/quadriceps cross-sectional area) were also assessed. Sex- and age-related differences in these indices were analyzed. The thigh cross-sectional area in men and women decreased by 0.6% and 0.5%/year, respectively, because of a decrease in muscle cross-sectional area (men 75.2%, women 40.6%), fat cross-sectional area (men 24.4%, women 59.6%) and bone cross-sectional area (men 0.5%, women -0.2%). Muscle cross-sectional area in men and women decreased by 0.6% and 0.4%/year, respectively, because of a decrease in quadriceps cross-sectional area (men 65.6%, women 81.6%) and non-quadriceps cross-sectional area (men 34.4%, women 18.4%). Muscle quality in men and women decreased by 0.4% and 0.3%/year, respectively. Thigh cross-sectional area decreased with age mainly because of a decrease in muscle cross-sectional area in men and fat cross-sectional area in women. The rate of decrease in muscle cross-sectional area was 1.5-fold higher in men than in women. Muscle cross-sectional area decreased with age mainly because of a decrease in quadriceps cross-sectional area, especially in women. Decrease in muscle quality with age was similar in both sexes. © 2014 Japan Geriatrics Society.
Benchmarking electronic-state excitation cross sections for electron-N{sub 2} collisions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kato, Hidetoshi; Suzuki, Daisuke; Ohkawa, Mizuha
2010-04-15
We report differential cross sections for electron impact excitation of the a {sup 1{Pi}}{sub g}, C {sup 3{Pi}}{sub u}, E {sup 3{Sigma}}{sub g}{sup +}, a{sup ''} {sup 1{Sigma}}{sub g}{sup +}, b {sup 1{Pi}}{sub u}, c{sub 3} {sup 1{Pi}}{sub u}, o{sub 3} {sup 1{Pi}}{sub u}, b{sup '} {sup 1{Sigma}}{sub u}{sup +}, c{sub 4}{sup '} {sup 1{Sigma}}{sub u}{sup +}, G {sup 3{Pi}}{sub u}, and F {sup 3{Pi}}{sub u} electronic states in N{sub 2}. The incident electron energies are 20, 30, and 40 eV, while the scattered electron angles are 10 deg. and 20 deg. These kinematic conditions were specifically targeted in ordermore » to try and shed new light on the worrying discrepancies that exist in the literature for the a {sup 1{Pi}}{sub g}, C {sup 3{Pi}}{sub u}, E {sup 3{Sigma}}{sub g}{sup +}, and a{sup ''} {sup 1{Sigma}}{sub g}{sup +} cross sections, and in general the present measurements confirm that those from the more recent results of the University of California, Fullerton, and the Jet Propulsion Laboratory [M. A. Khakoo, P. V. Johnson, I. Ozkay, P. Yan, S. Trajmar, and I. Kanik, Phys. Rev. A 71, 062703 (2005); C. P. Malone, P. V. Johnson, I. Kanik, B. Ajdari, and M. A. Khakoo, Phys. Rev. A 79, 032704 (2009)] are reliable. In addition, we provide a rigorous cross-check for the remaining seven electronic states, where the only recent comprehensive study is from Khakoo and colleagues [Phys. Rev. A 77, 012704 (2008)]. Here, however, some of those cross sections are confirmed and others are not, suggesting that further work is still needed.« less
Lienhardt, Andrea; Rabenschlag, Franziska; Panfil, Eva-Maria
2018-06-08
The practice of special observation in adults in the German-speaking part of Switzerland - a descriptive cross-sectional study Abstract. Psychiatric Special Observation (PSO) is an intervention often used by nurses to prevent service users of harming themselves or to protect others. The intervention ranges between control and therapy and is resource intensive. Despite the widespread use of PSO, there is still no data on the practice of the intervention in Switzerland. What is the current practice of PSO in adults in psychiatric hospitals in the German-speaking part of Switzerland? Descriptive cross-sectional study. Nurses from inpatient psychiatric services in the German-speaking part of Switzerland completed a questionnaire based on a concept analysis of PSO. 538 questionnaires were analysed. PSO was more often conducted intermittent than as constant observation. In more than one out of four cases, suicidality reasoned as a cause for prescription. Nurses generally used standardized instruments to assess the risk of harming oneself or others. The duration of PSO lasted eight hours or more in three out of four cases. In every fifth case, there was no validation of the need of the intervention taking place during one shift. Nurses have a neutral attitude towards the intervention and are experiencing no or weak negative feelings during performance of PSO. The results suggest that there is an inconsistent performance of PSO in Switzerland as well as in other countries. The validation of the need of the intervention is insufficient. To facilitate PSO as a justified performance, the preparation of an interprofessional guideline is recommended.
Barah, F; Gonçalves, V
2010-05-01
Antibiotic misuse contributes to the growing problem of microbial resistance. To understand the current knowledge and practices regarding antibiotic use among Syrians, we conducted a cross-sectional study of 430 randomly selected adult residents of Kalamoon in the Syrian Arab Republic using a questionnaire. A high proportion (85%) had taken antibiotics in the past 4 weeks and 34% were not aware of the dangers of antibiotics. Of 365 participants, only 43% were prescribed the antibiotic by a physician to treat the condition, while 57% used an old prescription or took someone else's advice. Males, younger individuals, and those with low and medium income and lower educational status showed poorer practice and lower knowledge towards antibiotics. Educational efforts are needed to reduce patient demand for antibiotics.
Dissociative recombination of O2(+), NO(+) and N2(+)
NASA Technical Reports Server (NTRS)
Guberman, S. L.
1983-01-01
A new L(2) approach for the calculation of the threshold molecular capture width needed for the determination of DR cross sections was developed. The widths are calculated with Fermi's golden rule by substituting Rydberg orbitals for the free electron continuum coulomb orbital. It is shown that the calculated width converges exponentially as the effective principal quantum number of the Rydberg orbital increases. The threshold capture width is then easily obtained. Since atmospheric recombination involves very low energy electrons, the threshold capture widths are essential to the calculation of DR cross sections for the atmospheric species studied here. The approach described makes use of bound state computer codes already in use. A program that collects width matrix elements over CI wavefunctions for the initial and final states is described.
NASA Astrophysics Data System (ADS)
Reifarth, R.; Dababneh, S.; Fiebiger, S.; Glorius, J.; Göbel, K.; Heil, M.; Hillmann, P.; Heftrich, T.; Langer, C.; Meusel, O.; Plag, R.; Schmidt, S.; Slavkovská, Z.; Veltum, D.; Weigand, M.; Wiesner, C.; Wolf, C.; Zadeh, A.
2018-01-01
The neutron capture cross section of radioactive isotopes for neutron energies in the keV region will be measured by a time-of-flight (TOF) experiment. NAUTILUS will provide a unique facility realizing the TOF technique with an ultra-short flight path at the FRANZ setup at Goethe-University Frankfurt am Main, Germany. A highly optimized spherical photon calorimeter will be built and installed at an ultra-short flight path. This new method allows the measurement of neutron capture cross sections on extremely small sample as needed in the case of 85Kr, which will be produced as an isotopically pure radioactive sample. The successful measurement will provide insights into the dynamics of the late stages of stars, an important independent check of the evolution of the Universe and the proof of principle.
Data Needs and Modeling of the Upper Atmosphere
NASA Astrophysics Data System (ADS)
Brunger, M. J.; Campbell, L.
2007-04-01
We present results from our enhanced statistical equilibrium and time-step codes for atmospheric modeling. In particular we use these results to illustrate the role of electron-driven processes in atmospheric phenomena and the sensitivity of the model results to data inputs such as integral cross sections, dissociative recombination rates and chemical reaction rates.
Discrepancies Confer Vulnerability to Depressive Symptoms: A Three-Wave Longitudinal Study
ERIC Educational Resources Information Center
Sherry, Simon B.; Mackinnon, Sean P.; Macneil, Matthew A.; Fitzpatrick, Skye
2013-01-01
Discrepancies (i.e., a subjective sense of falling short of one's own standards) are a key part of the perfectionism construct. Theory suggests discrepancies confer vulnerability to depressive symptoms. Since most research in this area is cross-sectional, longitudinal research is needed to disentangle directionality of relationships and to permit…
Carer Knowledge and Perceptions of Healthy Lifestyles for Adults with Intellectual Disabilities
ERIC Educational Resources Information Center
Melville, Craig A.; Hamilton, Sarah; Miller, Susan; Boyle, Susan; Robinson, Nicola; Pert, Carol; Hankey, Catherine R.
2009-01-01
Background: Carers can have a significant impact supporting people with intellectual disabilities to make healthy lifestyle choices. This study examines carers' training needs on diet and physical activity. Methods: A cross-sectional survey was undertaken of the knowledge and perceptions of carers supporting adults with intellectual disabilities.…
Factors Contributing to the Uptake and Maintenance of Regular Exercise Behaviour in Emerging Adults
ERIC Educational Resources Information Center
Langdon, Jody; Johnson, Chad; Melton, Bridget
2017-01-01
Objective: To identify the influence of parental autonomy support, basic need satisfaction and motivation on emerging adults' physical activity level and exercise behaviours. Design: Cross-sectional survey. Setting: This study convenience-sampled approximately 435 college students identified as emerging adults--aged 18-25 years, who did not have a…
What Leaders Need to Know and Do: A Leadership Competencies Scorecard
ERIC Educational Resources Information Center
Ruben, Brent D.
2006-01-01
Brent Ruben introduces readers to a framework that surveys, summarizes, and synthesizes a broad cross section of the contemporary writings on leadership. The book organizes that literature into five broad competency areas, each of which is composed of a number of themes, and provides a Leadership Competencies Scorecard Inventory that allows…
Evaluation of AM2 2 1 Lay Pattern Over a 25 CBR Subgrade
2018-04-30
penetrometer in shallow pavement applications. Designation : D 6951. West Conshohocken, PA: ASTM International. ____. 2010. Standard test method for...Department of the Army position unless so designated by other authorized documents. DESTROY THIS REPORT WHEN NO LONGER NEEDED. DO NOT RETURN IT TO...27 Figure 3.21. Surveying designated cross section
Changes in Student Motivational Structure During Adolescence: A Pilot Study.
ERIC Educational Resources Information Center
Gnagey, William J.
This is a cross-sectional, descriptive study of the motivational profiles of 524 students from grade 7 through the freshman year in college. A new Motivation Inventory was administered to all students. This instrument measures six classes of needs referred to by Abraham Maslow as physiological, safety, love and belonging, esteem,…
Factors Associated with Aggressive Behavior among Nursing Home Residents with Dementia
ERIC Educational Resources Information Center
Whall, Ann L.; Colling, Kathleen B.; Kolanowski, Ann; Kim, HyoJeong; Hong, Gwi-Ryung Son; DeCicco, Barry; Ronis, David L.; Richards, Kathy C.; Algase, Donna; Beck, Cornelia
2008-01-01
Purpose: In an attempt to more thoroughly describe aggressive behavior in nursing home residents with dementia, we examined background and proximal factors as guided by the Need-Driven Dementia-Compromised Behavior model. Design and Methods: We used a multivariate cross-sectional survey with repeated measures; participants resided in nine randomly…
ERIC Educational Resources Information Center
Fountain, Lily
2011-01-01
This cross-sectional descriptive study of the Model of Domain Learning, which describes learners' progress from acclimation through competence to proficiency through the interplay of knowledge, interest and strategic processing/critical thinking (CT), examined its extension to maternity nursing. Based on the identified need for valid, reliable…
Stage Sequences of Adolescent Substance Use: A Prospective Longitudinal Approach.
ERIC Educational Resources Information Center
Collins, Linda M; And Others
Past research based primarily on cross-sectional data, has suggested a Guttman scale of substance use onset where marijuana use is preceded by alcohol use, and where sometimes tobacco is placed between alcohol and marijuana. Prospective longitudinal data is needed to determine whether the stages form a temporal sequence. A new statistical…
ERIC Educational Resources Information Center
Pisani, Anthony R.; Wyman, Peter A.; Petrova, Mariya; Schmeelk-Cone, Karen; Goldston, David B.; Xia, Yinglin; Gould, Madelyn S.
2013-01-01
To develop and refine interventions to prevent youth suicide, knowledge is needed about specific processes that reduce risk at a population level. Using a cross-sectional design, the present study tested hypotheses regarding associations between self-reported suicide attempts, emotion regulation difficulties, and positive youth-adult relationships…
Whitebark pine diameter growth response to removal of competition
Robert E. Keane; Kathy L. Gray; Laura J. Dickinson
2007-01-01
Silvicultural cutting treatments may be needed to restore whitebark pine (Pinus albicaulis) forests, but little is known of the response of this species to removal of competition through prescribed burning or silvicultural cuttings. We analyzed stem cross-sections from 48 whitebark pine trees in Montana around which most of the competing vegetation...
Common Perceptions of Parents Requesting Personal Exemption from Vaccination
ERIC Educational Resources Information Center
Luthy, Karlen E.; Beckstrand, Renea L.; Meyers, Carly J. H.
2013-01-01
School nurses, as vaccination advocates, need to be aware of parents' common concerns regarding vaccines, so the nurse can develop strategies to communicate with parents. The purpose of this cross sectional, descriptive study was to identify common reasons parents in Utah seek exempting rather than vaccinating their children. Data were collected…
Interagency Collaboration with High-Risk Gang Youth.
ERIC Educational Resources Information Center
Okamoto, Scott K.
This article describes the results of a study on interagency collaboration required to make major systemic changes in order to address the needs of emotionally and behaviorally disturbed youth. Interviews were conducted with practitioners from a cross-section of agencies that worked with high-risk gang youth. The intent was to examine both the…
Piloting a European Employer Survey on Skill Needs: Illustrative Findings. Research Paper No 36
ERIC Educational Resources Information Center
Sofroniou, Nicholas, Ed.; Zukersteinova, Alena, Ed.
2013-01-01
Today, information and data on skills development come mainly from household and employees surveys: trends in the labour market, demand and supply of skills, data on skill mismatch and skills obsolescence. Recurrent analysis of individual cross-sectional data and their extrapolation into the future indicates significant structural changes over…
A study for the installation of the TEXT heavy-ion beam probe on DIII-D
DOE Office of Scientific and Technical Information (OSTI.GOV)
Edmonds, P.H.; Solano, E.R.; Bravenec, R.V.
1997-01-01
An assessment of the feasibility of installing the TEXT 2 MeV heavy-ion beam probe on the DIII-D tokamak has been completed. Detailed drawings of the machine cross section were imported into the CAD application AutoCAD. A set of programs written in AutoLisp were used to generate trajectories. Displays of the accessible cross section of the plasma, scan lines for the entire range of primary beam energy and injection angle ranges, and sample{endash}volume dimensions can be rapidly generated. Because of the large deflection between the primary input beam and the emergent secondary beam, either the analyzer needs to be tracked overmore » a {plus_minus}20{degree} angle or secondary poloidal deflector plates need to be installed at the exit port. Toroidal deflector plates will be installed at both the injection and exit ports to compensate for toroidal displacements and deflections. The sample volumes generated by this procedure are within a few centimeters of the locations derived from a full three-dimensional calculation.{copyright} {ital 1997 American Institute of Physics.}« less
Cross-Section Measurements in the Fast Neutron Energy Range
NASA Astrophysics Data System (ADS)
Plompen, Arjan
2006-04-01
Generation IV focuses research for advanced nuclear reactors on six concepts. Three of these concepts, the lead, gas and sodium fast reactors (LFR, GFR and SFR) have fast neutron spectra, whereas a fourth, the super-critical water reactor (SCWR), can be configured to have a fast spectrum. Such fast neutron spectra are essential to meet the sustainability objective of GenIV. Nuclear data requirements for GenIV concepts will therefore emphasize the energy region from about 1 keV to 10 MeV. Here, the potential is illustrated of the GELINA neutron time-of-flight facility and the Van de Graaff laboratory at IRMM to measure the relevant nuclear data in this energy range: the total, capture, fission and inelastic-scattering cross sections. In particular, measurement results will be shown for lead and bismuth inelastic scattering for which the need was recently expressed in a quantitative way by Aliberti et al. for Accelerator Driven Systems. Even without completion of the quantitative assessment of the data needs for GenIV concepts at ANL it is clear that this particular effort is of relevance to LFR system studies.
Ishaq, Rabia; Baloch, Nosheen Sikander; Iqbal, Qaiser; Saleem, Fahad; Hassali, Mohamed Azmi; Iqbal, Javeid; Ahmed, Fiaz Ud Din; Anwar, Mohammad; Haider, Sajjad; Godman, Brian
2017-08-01
There is increasing prevalence of caesarean sections (CS) worldwide; however, there are concerns about their rates in some countries, including potential fears among mothers. Consequently, we aimed to determine the frequency of CS, and explore patient's perception towards CS attending public hospitals in Pakistan, to provide future guidance. A two-phased study design (retrospective and cross sectional) was adopted. A retrospective study was conducted to assess the frequency of CS over one year among four public hospitals. A cross sectional study was subsequently conducted to determine patients' perception towards CS attending the four tertiary care public hospitals in Quetta city, Pakistan, which is where most births take place. Overall prevalence of CS was 13.1% across the four hospitals. 728 patients were approached and 717 responded to the survey. Although 78.8% perceived CS as dangerous, influenced by education (p = 0.004), locality (p = 0.001) and employment status (p = 0.001), 74.5% of patients were in agreement that this is the best approach to save mother's and baby's lives if needed. 62% of respondents reported they would like to avoid CS if they could due to post-operative pain, and 58.9% preferred a normal delivery. There was also a significant association with education (p = 0.001) and locality (p = 0.001) where respondents considered normal vaginal delivery as painful. The overall frequency of CS approximates to WHO recommendations, although there is appreciable variation among the four hospitals. When it comes to perception towards CS, women had limited information. There is a need to provide mothers with education during the antenatal period, especially those with limited education, to accept CS where needed.
Twist-3 contributions to wide-angle photoproduction of pions
NASA Astrophysics Data System (ADS)
Kroll, P.; Passek-Kumerički, K.
2018-04-01
We investigate wide-angle π0 photoproduction within the handbag approach to twist-3 accuracy. In contrast to earlier work both the 2-particle as well as the 3-particle twist-3 contributions are taken into account. It is shown that both are needed for consistent results that respect gauge invariance and crossing properties. The numerical studies reveal the dominance of the twist-3 contribution. With it fair agreement with the recent CLAS measurement of the π0 cross section is obtained. We briefly comment also on wide-angle photoproduction of other pseudoscalar mesons.
NASA Technical Reports Server (NTRS)
Diana, L. M.; Chaplin, R. L.; Brooks, D. L.; Adams, J. T.; Reyna, L. K.
1990-01-01
An improved technique is presented for employing the 2.3m spectrometer to measure total ionization cross sections, Q sub ion, for positrons incident on He. The new ionization cross section agree with the values reported earlier. Estimates are also presented of total elastic scattering cross section, Q sub el, obtained by subtracting from total scattering cross sections, Q sub tot, reported in the literature, the Q sub ion and Q sub Ps (total positronium formation cross sections) and total excitation cross sections, Q sub ex, published by another researcher. The Q sub ion and Q sub el measured with the 3m high resolution time-of-flight spectrometer for 54.9eV positrons are in accord with the results from the 2.3m spectrometer. The ionization cross sections are in fair agreement with theory tending for the most part to be higher, especially at 76.3 and 88.5eV. The elastic cross section agree quite well with theory to the vicinity of 50eV, but at 60eV and above the experimental elastic cross sections climb to and remain at about 0.30 pi a sub o sq while the theoretical values steadily decrease.
Nano-fabricated plasmonic optical transformer
Choo, Hyuck; Cabrini, Stefano; Schuck, P. James; Liang, Xiaogan; Yablonovitch, Eli
2015-06-09
The present invention provides a plasmonic optical transformer to produce a highly focuses optical beam spot, where the transformer includes a first metal layer, a dielectric layer formed on the first metal layer, and a second metal layer formed on the dielectric layer, where the first metal layer, the dielectric layer, and the second layer are patterned to a shape including a first section having a first cross section, a second section following the first section having a cross-section tapering from the first section to a smaller cross-section, and a third section following the second section having a cross-section matching the tapered smaller cross-section of the second section.
Ryder, Robert T.; Trippi, Michael H.; Swezey, Christopher S.; Crangle, Robert D.; Hope, Rebecca S.; Rowan, Elisabeth L.; Lentz, Erika E.
2012-01-01
Geologic cross section C-C' is the third in a series of cross sections constructed by the U.S. Geological Survey (USGS) to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section C-C' provides a regional view of the structural and stratigraphic framework of the Appalachian basin from north-central Ohio to the Valley and Ridge province in south-central Pennsylvania, a distance of approximately 260 miles (mi). This cross section is a companion to cross sections E-E' and D-D' that are located about 50 to 125 mi and 25 to 50 mi, respectively, to the southwest. Cross section C-C' contains much information that is useful for evaluating energy resources in the Appalachian basin. Although specific petroleum systems are not identified on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and preferred migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on what is shown on the cross section. Cross section C-C' also provides a general framework (stratigraphic units and general rock types) for the coal-bearing section, although the cross section lacks the detail to illustrate key elements of coal systems (such as paleoclimate, coal quality, and coal rank). In addition, cross section C-C' may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.
Transfer couplings and hindrance far below the barrier for 40 Ca + 96 Zr
Stefanini, A. M.; Montagnoli, G.; Esbensen, H.; ...
2015-01-29
The sub-barrier fusion excitation function of 40Ca + 96Zr has been measured down to cross sections ≃2.4µb, i.e. two orders of magnitude smaller than obtained in the previous experiment, where the sub-barrier fusion of this system was found to be greatly enhanced with respect to 40Ca + 90Zr, and the need of coupling to transfer channels was suggested. The purpose of this work was to investigate the behavior of 40Ca + 96Zr fusion far below the barrier. The smooth trend of the excitation function has been found to continue, and the logarithmic slope increases very slowly. No indication of hindrancemore » shows up, and a comparison with 48Ca + 96Zr is very useful in this respect. A new CC analysis of the complete excitation function has been performed, including explicitly one- and two-nucleon Q >0 transfer channels. Such transfer couplings bring significant cross section enhancements, even at the level of a few µb. Locating the hindrance threshold, if any, in 40Ca + 96Zr would require challenging measurements of cross sections in the sub-µb range.« less
Transverse liquid fuel jet breakup, burning, and ignition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Li, Hsi-shang
1990-01-01
An analytical/numerical study of the breakup, burning, and ignition of liquid fuels injected transversely into a hot air stream is conducted. The non-reacting liquid jet breakup location is determined by the local sonic point criterion first proposed by Schetz, et al. (1980). Two models, one employing analysis of an elliptical jet cross-section and the other employing a two-dimensional blunt body to represent the transverse jet, have been used for sonic point calculations. An auxiliary criterion based on surface tension stability is used as a separate means of determining the breakup location. For the reacting liquid jet problem, a diffusion flamemore » supported by a one-step chemical reaction within the gaseous boundary layer is solved along the ellipse surface in subsonic crossflow. Typical flame structures and concentration profiles have been calculated for various locations along the jet cross-section as a function of upstream Mach numbers. The integrated reaction rate along the jet cross-section is used to predict ignition position, which is found to be situated near the stagnation point. While a multi-step reaction is needed to represent the ignition process more accurately, the present calculation does yield reasonable predictions concerning ignition along a curved surface.« less
The reflection of airborne UV laser pulses from the ocean
NASA Technical Reports Server (NTRS)
Hoge, F. E.; Krabill, W. B.; Swift, R. N.
1984-01-01
It is experimentally shown here for the first time that the normalized laser backscatter cross-section of the sea surface is a function of elevation or height position on teh ocean wave. All data were taken off-nadir, resulting in incidence angles of about 6.5 deg measured relative to the normal to mean sea level (MSL). In the limited data sets analyzed to date, the normalized backscatter cross-section was found to be higher in wave crest regions and lower in wave troughs for a swell-dominated sea over which the wind speed was 5 m/s. The reverse was found to be the case for a sea that was driven by a 14 m/s wind. These isolated results show that the MSL, as measured by an off-nadir and/or multibeam type satellite laser altimeter, will be found above, at, or below the true MSL, depending on the local sea conditions existing in the footprint of the altimeter. Airborne nadir-pointed laser altimeter data for a wide variety of sea conditions are needed before a final determination can be made of the effect of sea state on the backscatter cross-section as measured by a down-looking satellite laser system.
Limit Theory for Panel Data Models with Cross Sectional Dependence and Sequential Exogeneity
Kuersteiner, Guido M.; Prucha, Ingmar R.
2013-01-01
The paper derives a general Central Limit Theorem (CLT) and asymptotic distributions for sample moments related to panel data models with large n. The results allow for the data to be cross sectionally dependent, while at the same time allowing the regressors to be only sequentially rather than strictly exogenous. The setup is sufficiently general to accommodate situations where cross sectional dependence stems from spatial interactions and/or from the presence of common factors. The latter leads to the need for random norming. The limit theorem for sample moments is derived by showing that the moment conditions can be recast such that a martingale difference array central limit theorem can be applied. We prove such a central limit theorem by first extending results for stable convergence in Hall and Hedye (1980) to non-nested martingale arrays relevant for our applications. We illustrate our result by establishing a generalized estimation theory for GMM estimators of a fixed effect panel model without imposing i.i.d. or strict exogeneity conditions. We also discuss a class of Maximum Likelihood (ML) estimators that can be analyzed using our CLT. PMID:23794781
NASA Astrophysics Data System (ADS)
Weissman, David E.; Davidson, Kenneth L.; Brown, Robert A.; Friehe, Carl A.; Li, Fuk
1994-05-01
The Frontal Air-Sea Interaction Experiment (FASINEX) provided a unique data set with coincident airborne scatterometer measurements of the ocean surface radar cross section (RCS) (at Ku band) and near-surface wind and wind stress. These data have been analyzed to study new model functions which relate wind speed and surface friction velocity (square root of the kinematic wind stress) to the radar cross section and to better understand the processes in the boundary layer that have a strong influence on the radar backscatter. Studies of data from FASINEX indicate that the RCS has a different relation to the friction velocity than to the wind speed. The difference between the RCS models using these two variables depends on the polarization and the incidence angle. The radar data have been acquired from the Jet Propulsion Laboratory airborne scatterometer. These data span 10 different flight days. Stress measurements were inferred from shipboard instruments and from aircraft flying at low altitudes, closely following the scatterometer. Wide ranges of radar incidence angles and environmental conditions needed to fully develop algorithms are available from this experiment.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sandmeier, H.A.; Hansen, G.E.; Seamon, R.E.
This report lists 42-group, coupled, neutron -gamma cross sections for H, D, T, /sup 3/He, /sup 4/He, /sup 6/Li, /sup 7/Li, Be, /sup 10/B, /sup 11/B, C, N, O, Na, Mg, Ai, Si, Cl, A, K, Ca, Fe, Cu, W, Pb, /sup 235/U, /sup 238/U, / sup 239/Pu, and /sup 240/Pu. Most of these materials are used in nuclear- weaponseffects calculations, where the elements for air, ground, and sea water are needed. Further, lists are given of cross sections for materials used in nuclear weapons vulnerability calculations, such as the elements of high explosives as well as materials that willmore » undergo fusion and fission. Most of the common reactor materials are also listed. The 42 coupled neutron-gamma groups are split into 30 neutron groups (17 MeV through 1.39 x 10/sup -4/ eV) and 12 gamma groups (10 MeV through 0.01 MeV). Data sources and averaging schemes used for the development of these multigroup parameters are given. (119 tables) (auth)« less
Exploring students' conceptions of science learning via drawing: a cross-sectional analysis
NASA Astrophysics Data System (ADS)
Hsieh, Wen-Min; Tsai, Chin-Chung
2017-02-01
This cross-sectional study explored students' conceptions of science learning via drawing analysis. A total of 906 Taiwanese students in 4th, 6th, 8th, 10th, and 12th grade were asked to use drawing to illustrate how they conceptualise science learning. Students' drawings were analysed using a coding checklist to determine the presence or absence of specified attributes. Data analysis showed that the majority of students pictured science learning as school-based, involving certain types of experiment or teacher lecturing. In addition, notable cross-sectional differences were found in the 'Activity' and 'Emotions and attitudes' categories in students' drawings. Three major findings were made: (1) lower grade level students conceptualised science learning with a didactic approach, while higher graders might possess a quantitative view of science learning (i.e. how much is learned, not how well it is learned), (2) students' positive and negative emotions and attitudes toward science learning reversed around middle school, and (3) female students expressed significantly more positive emotions and attitudes than their male counterparts. In conclusion, higher graders' unfruitful conceptions of science learning warrant educators' attention. Moreover, further investigation of girls' more positive emotions and attitudes found in this study is needed.
Robust mode space approach for atomistic modeling of realistically large nanowire transistors
NASA Astrophysics Data System (ADS)
Huang, Jun Z.; Ilatikhameneh, Hesameddin; Povolotskyi, Michael; Klimeck, Gerhard
2018-01-01
Nanoelectronic transistors have reached 3D length scales in which the number of atoms is countable. Truly atomistic device representations are needed to capture the essential functionalities of the devices. Atomistic quantum transport simulations of realistically extended devices are, however, computationally very demanding. The widely used mode space (MS) approach can significantly reduce the numerical cost, but a good MS basis is usually very hard to obtain for atomistic full-band models. In this work, a robust and parallel algorithm is developed to optimize the MS basis for atomistic nanowires. This enables engineering-level, reliable tight binding non-equilibrium Green's function simulation of nanowire metal-oxide-semiconductor field-effect transistor (MOSFET) with a realistic cross section of 10 nm × 10 nm using a small computer cluster. This approach is applied to compare the performance of InGaAs and Si nanowire n-type MOSFETs (nMOSFETs) with various channel lengths and cross sections. Simulation results with full-band accuracy indicate that InGaAs nanowire nMOSFETs have no drive current advantage over their Si counterparts for cross sections up to about 10 nm × 10 nm.
NASA Technical Reports Server (NTRS)
Weissman, David E.; Davidson, Kenneth L.; Brown, Robert A.; Friehe, Carl A.; Li, Fuk
1994-01-01
The Frontal Air-Sea Interaction Experiment (FASINEX) provided a unique data set with coincident airborne scatterometer measurements of the ocean surface radar cross section (RCS)(at Ku band) and near-surface wind and wind stress. These data have been analyzed to study new model functions which relate wind speed and surface friction velocity (square root of the kinematic wind stress) to the radar cross section and to better understand the processes in the boundary layer that have a strong influence on the radar backscatter. Studies of data from FASINEX indicate that the RCS has a different relation to the friction velocity than to the wind speed. The difference between the RCS models using these two variables depends on the polarization and the incidence angle. The radar data have been acquired from the Jet Propulsion Laboratory airborne scatterometer. These data span 10 different flight days. Stress measurements were inferred from shipboard instruments and from aircraft flying at low altitudes, closely following the scatterometer. Wide ranges of radar incidence angles and environmental conditions needed to fully develop algorithms are available from this experiment.
Multistrand superconductor cable
Borden, Albert R.
1985-01-01
Improved multistrand Rutherford-type superconductor cable is produced by using strands which are preformed, prior to being wound into the cable, so that each strand has a variable cross section, with successive portions having a substantially round cross section, a transitional oval cross section, a rectangular cross section, a transitional oval cross section, a round cross section and so forth, in repetitive cycles along the length of the strand. The cable is wound and flattened so that the portions of rectangular cross section extend across the two flat sides of the cable at the strand angle. The portions of round cross section are bent at the edges of the flattened cable, so as to extend between the two flat sides. The rectangular portions of the strands slide easily over one another, so as to facilitate flexing and bending of the cable, while also minimizing the possibility of causing damage to the strands by such flexing or bending. Moreover, the improved cable substantially maintains its compactness and cross-sectional shape when the cable is flexed or bent.
Letamo, Gobopamang; Navaneetham, Kannan
2015-03-31
The objectives of this study are: (1) to estimate the prevalence of unmet need for family planning among married women using Botswana Family Health Survey 2007 data and (2) to identify risk factors for unmet need for family planning among married women. This study used secondary data from a cross-sectional survey that was conducted to provide a snapshot of health issues in Botswana. Nationally representative population survey data. 2601 married or in union women aged 15-49 years who participated in the 2007 Botswana Family Health Survey were included in the analysis. Unmet need for family planning, which was defined as the percentage of all fecund married women who are not using a method of contraception even though they do not want to get pregnant. Married women who had unmet need for family planning were 9.6% in 2007. Most of the unmet need was for limiting (6.7%) compared to spacing (2.9%). Unmet need for family planning was more likely to be among women whose partners disapproved of family planning, non-Christians, had one partner and had never discussed family planning with their partner. Women of low parity, aged 25-34 years, and greater exposure to mass media, were less likely to have experienced unmet need. The patterns and magnitude of covariates differed between unmet need for limiting and for spacing. The prevalence of unmet need for family planning was low in Botswana compared to other sub-Saharan African countries. The findings from this study reemphasise the importance of women's empowerment and men's involvement in women's sexual and reproductive healthcare needs and services. Different approaches are needed to satisfy the demand for family planning for spacing and limiting. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Pion Production Data Needed for Space Radiation
NASA Technical Reports Server (NTRS)
Norbury, John W.
2010-01-01
A recent discovery concerning the importance of hadron production in space radiation is that pions can contribute up to twenty percent of the dose from galactic cosmic ray interactions (S. Aghara, S. Blattnig, J. Norbury, R. Singleterry, Nuclear Instruments and Methods, Vol. 267, 2009, p. 1115). Although the contribution for dose equivalent will be smaller, the dose contribution could be important for fluence based radiation models. Pion production cross sections will be an essential ingredient to such models, and it is of interest to investigate the adequacy of the pion production experimental data base for energies relevant to space radiation. The pion production threshold in nucleon - nucleon reactions is at 280 MeV and, in an interesting accident of nature, this lies near the peak of the galactic cosmic ray proton spectrum. Therefore, pion production data are needed from threshold up to energies around 50 GeV/nucleon, where the galactic cosmic ray fluence is of decreasing importance. Total and differential cross section data for pion production in this energy range will be reviewed. The availability and accuracy of theoretical models will also be discussed. It will be shown that there are a significant lack of data in this important energy range and that theoretical models still need improvement.
Bethge, Matthias; Spanier, Katja; Neugebauer, Tjark; Mohnberg, Inka; Radoschewski, Friedrich Michael
2015-11-01
The purpose of this study was to assess associations of self-reported work ability as measured by the Work Ability Index (WAI) with modifiable behavioral and occupational health risks, health service utilization, and intended rehabilitation and pension requests. This is a cross-sectional study of a random sample of German employees aged 40-54 yrs on sickness benefits in 2012 (trial registration: DRKS00004824). In total, 1312 male and 1502 female employees were included in the analyses. Low WAI scores (i.e., <37 points) were associated with a higher prevalence of occupational and behavioral health risks; a higher likelihood of frequent visits to general, somatic, and psychologic specialists as well as hospital stays; and four to six times higher risks of intended rehabilitation and pension requests. A two-item version of the WAI was as strongly associated with intended rehabilitation and pension requests as the total score. This study indicates that the WAI is a sensitive screening tool to identify workers on sick leave with a probable need for rehabilitation. The WAI could support the assessment of need for rehabilitation by occupational health services in return-to-work strategies, which include the opportunity to access multiprofessional rehabilitation.
Nand, Khushboo Yamima; Oommen, Anu Mary; Chacko, Rabin Kurudamannil; Abraham, Vinod Joseph
2017-01-01
Chronic periodontitis is a common cause of poor oral health globally. Those at higher risk of this preventable and easily treatable condition need to be identified so that efforts can be taken to decrease disease burden and subsequent consequences. The aims of the study were (1) To compare the prevalence of chronic periodontitis among individuals with and without type 2 diabetes, aged 35-65 years from a rural block in Vellore, Tamil Nadu and (2) to assess risk factors for chronic periodontitis among individuals with diabetes. A cross-sectional study was done in nine villages of Kaniyambadi block, Vellore, between October 2015 and July 2016 among participants aged 35-65 years of a previous cross-sectional survey which had identified individuals with and without type 2 diabetes. Chronic periodontitis was assessed using the Community Periodontal Index and Treatment Needs index. Oral hygiene was assessed clinically using the Simplified Oral Hygiene Index. Diabetes was defined as on medication for type 2 diabetes or detected to have fasting blood glucose ≥126 mg/dl (in a previous survey). Chi-square test and odds ratios (adjusted using logistic regression) were used to study risk factors for periodontitis among those with diabetes. Prevalence of chronic periodontitis was 45.9% (95% confidence interval [CI]: 40.88%-50.9%) among 98 individuals with diabetes and 35.6% (95% CI: 30.91-40.29%) among 104 individuals without diabetes. Poor oral hygiene (odds ratio: 8.33, 95% CI: 3.33-25.00), low socioeconomic status (odds ratio: 3.19, 95% CI: 1.00-10.12), and smoking (odds ratio: 3.51, 95% CI: 1.17-10.51) were associated with periodontitis among diabetics. Individuals with type 2 diabetes have a higher prevalence of periodontitis. As poor oral hygiene is a strong risk factor for periodontitis, there is a need for targeted education regarding dental hygiene to reduce this preventable condition.
Ahern, Tracey; Gardner, Anne; Courtney, Mary
2016-08-01
This study investigated whether use of services of a breast care nurse (BCN) at any time during treatment for breast cancer led to reduced unmet needs and increased self-efficacy among women with breast cancer. A secondary aim was to analyse comparisons between urban and rural and remote dwellers. Participants were Australian women who completed treatment for breast cancer at least 6 months before the survey date, recruited through two national databases of women diagnosed with breast cancer. The cross-sectional online survey consisted of two well validated measures, the SCNS-SF34 and the CASE-Cancer Scale. Statistical data were analysed using SPSS, with chi-square used to measure statistical significance. A total of 902 participants responded to the survey. Unmet needs in the psychological domain were most prominent. Respondents who used the services of a BCN were significantly less likely to report unmet needs regarding tiredness, anxiety; future outlook; feelings about death and dying; patient care and support from medical staff; and provision of health systems and information. Scores of self-efficacy showed women using the services of a BCN had significantly higher self-efficacy when seeking and obtaining information (ρ ≤ 0.001) and understanding and participating in care (ρ = 0.032). Urban dwellers were more likely to have choice of health care service, but overall neither unmet needs nor perceived self-efficacy varied statistically significantly by remoteness. Women with breast cancer experience a range of unmet needs; however those using BCN services demonstrated positive outcomes in terms of decreased unmet needs and increased self-efficacy. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kyagaba, Emmanuel; Asamoah, Benedict Oppong; Emmelin, Maria; Agardh, Anette
2014-08-01
In 2010, unmet medical care and sexual health counseling needs were assessed among students at a Ugandan University. Unmet medical care need was associated with poor mental health, experience of sexual coercion, and poor self-rated health. Unmet sexual health counseling need was significantly associated with being female, coming from an urban area, low social participation, poor mental health status, experience of sexual coercion, poor self-rated health, inconsistent condom use, and having multiple sexual partners. Gender differences, poor mental health, sexual coercion, poor self-rated health, and risky sexual behavior must be considered when designing intervention models to reduce unmet health care needs among young people in this setting.
GRAPhEME: a setup to measure (n, xn γ) reaction cross sections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Henning, Greg; Bacquias, A.; Capdevielle, O.
2015-07-01
Most of nuclear reactor developments are using evaluated data base for numerical simulations. However, the considered databases present still large uncertainties and disagreements. To improve their level of precision, new measurements are needed, in particular for (n, xn) reactions, which are of great importance as they modify the neutron spectrum, the neutron population, and produce radioactive species. The IPHC group started an experimental program to measure (n, xn gamma) reaction cross sections using prompt gamma spectroscopy and neutron energy determination by time of flight. Measurements of (n, xn gamma) cross section have been performed for {sup 235,238}U, {sup 232}Th, {supmore » nat,182,183,184,186}W, {sup nat}Zr. The experimental setup is installed at the neutron beam at GELINA (Geel, Belgium). The setup has recently been upgraded with the addition of a highly segmented 36 pixels planar HPGe detector. Significant efforts have been made to reduce radiation background and electromagnetic perturbations. The setup is equipped with a high rate digital acquisition system. The analysis of the segmented detector data requires a specific procedure to account for cross signals between pixels. An overall attention is paid to the precision of the measurement. The setup characteristic and the analysis procedure will be presented along with the acquisition and analysis challenges. Examples of results and their impact on models will be discussed. (authors)« less
Risk cross sections and their application to risk estimation in the galactic cosmic-ray environment
NASA Technical Reports Server (NTRS)
Curtis, S. B.; Nealy, J. E.; Wilson, J. W.; Chatterjee, A. (Principal Investigator)
1995-01-01
Radiation risk cross sections (i.e. risks per particle fluence) are discussed in the context of estimating the risk of radiation-induced cancer on long-term space flights from the galactic cosmic radiation outside the confines of the earth's magnetic field. Such quantities are useful for handling effects not seen after low-LET radiation. Since appropriate cross-section functions for cancer induction for each particle species are not yet available, the conventional quality factor is used as an approximation to obtain numerical results for risks of excess cancer mortality. Risks are obtained for seven of the most radiosensitive organs as determined by the ICRP [stomach, colon, lung, bone marrow (BFO), bladder, esophagus and breast], beneath 10 g/cm2 aluminum shielding at solar minimum. Spectra are obtained for excess relative risk for each cancer per LET interval by calculating the average fluence-LET spectrum for the organ and converting to risk by multiplying by a factor proportional to R gamma L Q(L) before integrating over L, the unrestricted LET. Here R gamma is the risk coefficient for low-LET radiation (excess relative mortality per Sv) for the particular organ in question. The total risks of excess cancer mortality obtained are 1.3 and 1.1% to female and male crew, respectively, for a 1-year exposure at solar minimum. Uncertainties in these values are estimated to range between factors of 4 and 15 and are dominated by the biological uncertainties in the risk coefficients for low-LET radiation and in the LET (or energy) dependence of the risk cross sections (as approximated by the quality factor). The direct substitution of appropriate risk cross sections will eventually circumvent entirely the need to calculate, measure or use absorbed dose, equivalent dose and quality factor for such a high-energy charged-particle environment.
Asres, Yihunie Hibstie; Mathuthu, Manny; Birhane, Marelgn Derso
2018-04-22
This study provides current evidence about cross-section production processes in the theoretical and experimental results of neutron induced reaction of uranium isotope on projectile energy range of 1-100 MeV in order to improve the reliability of nuclear stimulation. In such fission reactions of 235 U within nuclear reactors, much amount of energy would be released as a product that able to satisfy the needs of energy to the world wide without polluting processes as compared to other sources. The main objective of this work is to transform a related knowledge in the neutron-induced fission reactions on 235 U through describing, analyzing and interpreting the theoretical results of the cross sections obtained from computer code COMPLET by comparing with the experimental data obtained from EXFOR. The cross section value of 235 U(n,2n) 234 U, 235 U(n,3n) 233 U, 235 U(n,γ) 236 U, 235 U(n,f) are obtained using computer code COMPLET and the corresponding experimental values were browsed by EXFOR, IAEA. The theoretical results are compared with the experimental data taken from EXFOR Data Bank. Computer code COMPLET has been used for the analysis with the same set of input parameters and the graphs were plotted by the help of spreadsheet & Origin-8 software. The quantification of uncertainties stemming from both experimental data and computer code calculation plays a significant role in the final evaluated results. The calculated results for total cross sections were compared with the experimental data taken from EXFOR in the literature, and good agreement was found between the experimental and theoretical data. This comparison of the calculated data was analyzed and interpreted with tabulation and graphical descriptions, and the results were briefly discussed within the text of this research work. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.
Unified continuum damage model for matrix cracking in composite rotor blades
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pollayi, Hemaraju; Harursampath, Dineshkumar
This paper deals with modeling of the first damage mode, matrix micro-cracking, in helicopter rotor/wind turbine blades and how this effects the overall cross-sectional stiffness. The helicopter/wind turbine rotor system operates in a highly dynamic and unsteady environment leading to severe vibratory loads present in the system. Repeated exposure to this loading condition can induce damage in the composite rotor blades. These rotor/turbine blades are generally made of fiber-reinforced laminated composites and exhibit various competing modes of damage such as matrix micro-cracking, delamination, and fiber breakage. There is a need to study the behavior of the composite rotor system undermore » various key damage modes in composite materials for developing Structural Health Monitoring (SHM) system. Each blade is modeled as a beam based on geometrically non-linear 3-D elasticity theory. Each blade thus splits into 2-D analyzes of cross-sections and non-linear 1-D analyzes along the beam reference curves. Two different tools are used here for complete 3-D analysis: VABS for 2-D cross-sectional analysis and GEBT for 1-D beam analysis. The physically-based failure models for matrix in compression and tension loading are used in the present work. Matrix cracking is detected using two failure criterion: Matrix Failure in Compression and Matrix Failure in Tension which are based on the recovered field. A strain variable is set which drives the damage variable for matrix cracking and this damage variable is used to estimate the reduced cross-sectional stiffness. The matrix micro-cracking is performed in two different approaches: (i) Element-wise, and (ii) Node-wise. The procedure presented in this paper is implemented in VABS as matrix micro-cracking modeling module. Three examples are presented to investigate the matrix failure model which illustrate the effect of matrix cracking on cross-sectional stiffness by varying the applied cyclic load.« less
Measurement of the n-p elastic scattering angular distribution at E{sub n}=14.9 MeV
DOE Office of Scientific and Technical Information (OSTI.GOV)
Boukharouba, N.; Bateman, F. B.; Carlson, A. D.
2010-07-15
The relative differential cross section for the elastic scattering of neutrons by protons was measured at an incident neutron energy E{sub n}=14.9 MeV and for center-of-mass scattering angles ranging from about 60 deg. to 180 deg. Angular distribution values were obtained from the normalization of the integrated data to the n-p total elastic scattering cross section. Comparisons of the normalized data to the predictions of the Arndt et al. phase-shift analysis, those of the Nijmegen group, and with the ENDF/B-VII.0 evaluation are sensitive to the value of the total elastic scattering cross section used to normalize the data. The resultsmore » of a fit to a first-order Legendre polynomial expansion are in good agreement in the backward scattering hemisphere with the predictions of the Arndt et al. phase-shift analysis, those of the Nijmegen group, and to a lesser extent, with the ENDF/B-VII.0 evaluation. A fit to a second-order expansion is in better agreement with the ENDF/B-VII.0 evaluation than with the other predictions, in particular when the total elastic scattering cross section given by Arndt et al. and the Nijmegen group is used to normalize the data. A Legendre polynomial fit to the existing n-p scattering data in the 14 MeV energy region, excluding the present measurement, showed that a best fit is obtained for a second-order expansion. Furthermore, the Kolmogorov-Smirnov test confirms the general agreement in the backward scattering hemisphere and shows that significant differences between the database and the predictions occur in the angular range between 60 deg. and 120 deg. and below 20 deg. Although there is good overall agreement in the backward scattering hemisphere, more precision small-angle scattering data and a better definition of the total elastic cross section are needed for an accurate determination of the shape and magnitude of the angular distribution.« less
A meta-analysis on progressive atrophy in intractable temporal lobe epilepsy
Caciagli, Lorenzo; Bernasconi, Andrea; Wiebe, Samuel; Koepp, Matthias J.; Bernasconi, Neda
2017-01-01
Objective: It remains unclear whether drug-resistant temporal lobe epilepsy (TLE) is associated with cumulative brain damage, with no expert consensus and no quantitative syntheses of the available evidence. Methods: We conducted a systematic review and meta-analysis of MRI studies on progressive atrophy, searching PubMed and Ovid MEDLINE databases for cross-sectional and longitudinal quantitative MRI studies on drug-resistant TLE. Results: We screened 2,976 records and assessed eligibility of 248 full-text articles. Forty-two articles met the inclusion criteria for quantitative evaluation. We observed a predominance of cross-sectional studies, use of different clinical indices of progression, and high heterogeneity in age-control procedures. Meta-analysis of 18/1 cross-sectional/longitudinal studies on hippocampal atrophy (n = 979 patients) yielded a pooled effect size of r = −0.42 for ipsilateral atrophy related to epilepsy duration (95% confidence interval [CI] −0.51 to −0.32; p < 0.0001; I2 = 65.22%) and r = −0.35 related to seizure frequency (95% CI −0.47 to −0.22; p < 0.0001; I2 = 61.97%). Sensitivity analyses did not change the results. Narrative synthesis of 25/3 cross-sectional/longitudinal studies on whole brain atrophy (n = 1,504 patients) indicated that >80% of articles reported duration-related progression in extratemporal cortical and subcortical regions. Detailed analysis of study design features yielded low to moderate levels of evidence for progressive atrophy across studies, mainly due to dominance of cross-sectional over longitudinal investigations, use of diverse measures of seizure estimates, and absence of consistent age control procedures. Conclusions: While the neuroimaging literature is overall suggestive of progressive atrophy in drug-resistant TLE, published studies have employed rather weak designs to directly demonstrate it. Longitudinal multicohort studies are needed to unequivocally differentiate aging from disease progression. PMID:28687722
Escaravage, Jody Hearn
2014-01-01
This cross-sectional secondary data analysis examined the ecological factors influencing the outcomes of families receiving services from a local department of social services to address child maltreatment risk and incidence. The results indicated that families that experienced repeated maltreatment also experienced greater poverty and material need than families with more successful outcomes. This study highlights the responsibility of the child welfare system to address deep-seated poverty issues of families experiencing child maltreatment risk and incidence.
Tsakos, G; Marcenes, W; Sheiham, A
2001-12-01
To examine whether there are significant cross-cultural differences in oral health-related quality of life and perceived treatment need between older people of similar clinical oral status living in Greece and Britain. Cross-sectional surveys of adults living independently aged 65 years or older. In Britain, data from the national diet and nutrition survey were used, while the Greek sample was drawn from two municipalities in Athens. Participants 753 in Britain and 681 in Greece. Oral health-related quality of life, assessed through the modified Oral Impacts on Daily Performance (OIDP) indicator, and perceived need for dental treatment. Thirty-nine per cent of Greek and 12.3% of British dentate and 47.6% of Greek and 16.3% of British edentulous participants had experienced oral impacts affecting their daily life in the last six months. The most prevalent impact was difficulty eating. Apart from that, 56.3% of Greek and 37.1% of British dentate and 33.5% of Greek and 25.3% of British edentulous participants perceived dental treatment need. After controlling for sociodemographic variables, perceived general health and clinical oral status, Greek dentate and edentulous participants were significantly more likely to experience oral impacts than their British counterparts, while in relation to perceived treatment need significant cross-cultural differences existed only between dentate respondents. The results indicated an independent cultural influence in the perception of oral impacts in older people.
AMPX: a modular code system for generating coupled multigroup neutron-gamma libraries from ENDF/B
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greene, N.M.; Lucius, J.L.; Petrie, L.M.
1976-03-01
AMPX is a modular system for producing coupled multigroup neutron-gamma cross section sets. Basic neutron and gamma cross-section data for AMPX are obtained from ENDF/B libraries. Most commonly used operations required to generate and collapse multigroup cross-section sets are provided in the system. AMPX is flexibly dimensioned; neutron group structures, and gamma group structures, and expansion orders to represent anisotropic processes are all arbitrary and limited only by available computer core and budget. The basic processes provided will (1) generate multigroup neutron cross sections; (2) generate multigroup gamma cross sections; (3) generate gamma yields for gamma-producing neutron interactions; (4) combinemore » neutron cross sections, gamma cross sections, and gamma yields into final ''coupled sets''; (5) perform one-dimensional discrete ordinates transport or diffusion theory calculations for neutrons and gammas and, on option, collapse the cross sections to a broad-group structure, using the one-dimensional results as weighting functions; (6) plot cross sections, on option, to facilitate the ''evaluation'' of a particular multigroup set of data; (7) update and maintain multigroup cross section libraries in such a manner as to make it not only easy to combine new data with previously processed data but also to do it in a single pass on the computer; and (8) output multigroup cross sections in convenient formats for other codes. (auth)« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
In FY 1990 Robotics Technology Development Program (RTDP) planning teams visited five DOE sites. These sites were selected by the Office of Technology Development to provide a needs basis for developing a 5-Year Plan. Visits to five DOE sites provided identification of needs for robotics technology development to support Environmental Restoration and Waste Management (ER WM) projects at those sites. Additional site visits will be conducted in the future to expand the planning basis. This volume summarizes both the results of the site visits and the needs and requirements of the priority ER WM activities at the sites, including potentialmore » needs for robotics and remote systems technology. It also discusses hazards associated with the site activities and any problems or technical uncertainties associated with dealing with the hazards in the performance of the ER WM work. Robotic or remote systems currently under development for remediation projects or waste operations are also discussed. The information in this document is organized principally by site, activity, and priority. Section 2.0, Site Needs, is based on information from the site visit reports and provides a summary which focuses on the site needs and requirements for each priority activity. Section 2.0 also records evaluations and discussions by the RTDP team following the site visit. Section 3.0, Commonality Assessment, documents similar site needs where common, or cross-cutting, robotics technology might be applied to several activities. Section 4.0 contains a summary of the site needs and requirements in tabular form. 1 tab.« less
Oberoi, Devesh; White, Victoria M; Seymour, John F; Miles Prince, H; Harrison, Simon; Jefford, Michael; Winship, Ingrid; Hill, David; Bolton, Damien; Kay, Anne; Millar, Jeremy; Doo, Nicole Wong; Giles, Graham
2017-11-01
This paper aims to examine the cross-sectional and longitudinal associations between patient-reported unmet needs and anxiety and depression for survivors of diffuse large B cell lymphoma (DLBCL) and multiple myeloma (MM). In a longitudinal study design, self-reported data were collected through telephone interviews at two time points approximately 7 (T1) and 15 (T2) months post-diagnosis. The sample was recruited through the population-based Victorian Cancer Registry. At T1 and T2, the study outcomes, anxiety and depression, were assessed using the Hospital Anxiety and Depression Scale (HADS) and unmet needs were measured using the Supportive Care Needs Survey (SCNS-SF34). Questions related to social/family problems, relationship problems and financial problems were also asked. A three-step multivariable hierarchical logistic regression analysis examined the relative role of T1 anxiety and depression, T1 and T2 unmet needs and other psychosocial factors with T2 anxiety and depression. Both cross-sectional and longitudinal associations were observed between unmet needs and psychological distress. T2 anxiety was associated with T1 anxiety (OR 4.75, 95% CI 1.86-11.09), T2 psychological needs (OR 1.68, 95% CI 1.34-2.11) and with T1 social problems (OR 2.33, 95% CI 1.03-5.05) in multivariate analysis. T2 depression was associated with both T1 (OR 1.28, 95% CI 1.06-1.57) and T2 psychological needs (OR 1.35, 95% CI 1.06-1.70), T2 physical needs (OR 1.89, 95% CI 1.27-2.81) and T1 depression (OR 4.52, 95% CI 1.88-10.86). Unmet needs that manifest following diagnosis and treatment may persist into early survivorship and contribute to psychological distress. Addressing these needs during treatment may diminish the risk of current and future anxiety and depression.
Farr, Olivia M; Rifas-Shiman, Sheryl L; Oken, Emily; Taveras, Elsie M; Mantzoros, Christos S
2017-11-01
Obstructive sleep apnea (OSA), typically manifested as snoring, is closely associated with obesity. However, the directionality of associations of OSA with cardiometabolic risk markers is unclear, as obesity increases risk for OSA, and OSA results in excess weight gain and its metabolic consequences. Less is known about how obesity and OSA may relate in children and adolescents and whether maternal OSA may influence the development of obesity and cardiometabolic dysfunction in offspring. Among 1078 children from the Project Viva cohort, we examined cross-sectionally and prospectively associations of parent-reported child or maternal snoring with cardiometabolic outcomes, including adiposity, adipokines, and insulin resistance. Cross-sectionally, child snoring was related to adiposity and metabolic risk, particularly body mass index (BMI; β 0.61kg/m 2 , 95% CI 0.33, 0.89; p<0.001), trunk fat mass index (β 0.23kg/m 2 , CI 0.12, 0.34; p<0.001), high-density lipoprotein cholesterol (β -1.47mg/dL, CI -2.69, -0.25; p=0.02), and metabolic risk z-score (β 0.08, CI 0.02, 0.14; p=0.01) after correction for covariates. Prospectively, adiposity (BMI, trunk fat, fat mass, and waist circumference) and cardiometabolic (leptin, HOMA-IR, CRP, and global metabolic risk) measures at mid-childhood (~7y) were associated with child snoring at the early teen visit (~12y) after correction for covariates. Child snoring at ~9y was related to changes in adiposity between mid-childhood and early teen visits. Child but not maternal snoring, was related to child adiposity and cardiometabolic outcomes. Adiposity and child snoring are associated with each other cross-sectionally and are each predictive of the other among children/adolescents prospectively. These results suggest similar mechanisms in pediatric/adolescent populations as in adults for the development of sleep-disordered breathing and sleep apnea that will need to be confirmed in randomized clinical trials. Importantly, this research points to the need to target both sleep and obesity in order to break this vicious cycle. Copyright © 2017 Elsevier Inc. All rights reserved.
Salazar, Ricardo; Dwivedi, Alok Kumar; Royall, Donald R
2017-01-01
In this cross-sectional study, we examined the neuropsychiatric profile of mild cognitive impairment (MCI) and Alzheimer's disease (AD) using the Neuropsychiatric Inventory Questionnaire (NPI-Q). Data were available on 875 controls, 339 MCI cases, and 975 AD participants. Surprisingly, differences in neuropsychiatric symptom (NPS) severity by ethnicity in subjects with AD, but not with MCI, were found. More so, in Hispanics with AD, a higher frequency in most of the individual NPI-Q symptom items of the scale was observed, except for apathy. After adjustment for clinical features, some individual NPI-Q symptoms also showed an association with Hispanic ethnicity in the control group that nearly reached statistical significance. There may be cross-ethnic differences in the neuropsychiatric presentation of AD in Hispanics versus non-Hispanic whites. Future studies are needed to clarify the etiology of these differences, and to assess the need for ethnicity-specific treatment and care-giving interventions.
Sions, Jaclyn Megan; Smith, Andrew Craig; Hicks, Gregory Evan; Elliott, James Matthew
2016-08-01
To evaluate intra- and inter-examiner reliability for the assessment of relative cross-sectional area, muscle-to-fat infiltration indices, and relative muscle cross-sectional area, i.e., total cross-sectional area minus intramuscular fat, from T1-weighted magnetic resonance images obtained in older adults with chronic low back pain. Reliability study. n = 13 (69.3 ± 8.2 years old) After lumbar magnetic resonance imaging, two examiners produced relative cross-sectional area measurements of multifidi, erector spinae, psoas, and quadratus lumborum by tracing regions of interest just inside fascial borders. Pixel-intensity summaries were used to determine muscle-to-fat infiltration indices; relative muscle cross-sectional area was calculated. Intraclass correlation coefficients were used to estimate intra- and inter-examiner reliability; standard error of measurement was calculated. Intra-examiner intraclass correlation coefficient point estimates for relative cross-sectional area, muscle-to-fat infiltration indices, and relative muscle cross-sectional area were excellent for multifidi and erector spinae across levels L2-L5 (ICC = 0.77-0.99). At L3, intra-examiner reliability was excellent for relative cross-sectional area, muscle-to-fat infiltration indices, and relative muscle cross-sectional area for both psoas and quadratus lumborum (ICC = 0.81-0.99). Inter-examiner intraclass correlation coefficients ranged from poor to excellent for relative cross-sectional area, muscle-to-fat infiltration indices, and relative muscle cross-sectional area. Assessment of relative cross-sectional area, muscle-to-fat infiltration indices, and relative muscle cross-sectional area in older adults with chronic low back pain can be reliably determined by one examiner from T1-weighted images. Such assessments provide valuable information, as muscle-to-fat infiltration indices and relative muscle cross-sectional area indicate that a substantial amount of relative cross-sectional area may be magnetic resonance-visible intramuscular fat in older adults with chronic low back pain. © 2015 American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Singh, Suvam; Naghma, Rahla; Kaur, Jaspreet; Antony, Bobby
2016-07-01
The total and ionization cross sections for electron scattering by benzene, halobenzenes, toluene, aniline, and phenol are reported over a wide energy domain. The multi-scattering centre spherical complex optical potential method has been employed to find the total elastic and inelastic cross sections. The total ionization cross section is estimated from total inelastic cross section using the complex scattering potential-ionization contribution method. In the present article, the first theoretical calculations for electron impact total and ionization cross section have been performed for most of the targets having numerous practical applications. A reasonable agreement is obtained compared to existing experimental observations for all the targets reported here, especially for the total cross section.
Parameterized Cross Sections for Pion Production in Proton-Proton Collisions
NASA Technical Reports Server (NTRS)
Blattnig, Steve R.; Swaminathan, Sudha R.; Kruger, Adam T.; Ngom, Moussa; Norbury, John W.; Tripathi, R. K.
2000-01-01
An accurate knowledge of cross sections for pion production in proton-proton collisions finds wide application in particle physics, astrophysics, cosmic ray physics, and space radiation problems, especially in situations where an incident proton is transported through some medium and knowledge of the output particle spectrum is required when given the input spectrum. In these cases, accurate parameterizations of the cross sections are desired. In this paper much of the experimental data are reviewed and compared with a wide variety of different cross section parameterizations. Therefore, parameterizations of neutral and charged pion cross sections are provided that give a very accurate description of the experimental data. Lorentz invariant differential cross sections, spectral distributions, and total cross section parameterizations are presented.
Campbell, Rachel; Vansteenkiste, Maarten; Delesie, Liesbeth; Soenens, Bart; Tobback, Els; Vogelaers, Dirk; Mariman, An
2016-11-01
Research has not yet examined the relationship between psychological need satisfaction, sleep, mindfulness, and health-related quality of life in people living with HIV. This cross-sectional study ( N = 101; 84% male; mean age = 45.48, SD = 12.75) found need satisfaction to relate positively to physical and mental health. Sleep quality fully mediated the association with physical health and partially mediated the association with mental health. Furthermore, mindfulness related to higher sleep quality through higher need satisfaction. Findings underscore the role of need satisfaction in determining health-related quality of life and sleep quality in people living with HIV and suggest that mindfulness may facilitate need satisfaction.
Malik, Sarah Alam; Watt, Graeme
2014-02-05
We motivate a measurement of various ratios of W and Z cross sections at the Large Hadron Collider (LHC) at large values of the boson transverse momentum (p T ≳ M W,Z ). We study the dependence of predictions for these cross-section ratios on the multiplicity of associated jets, the boson p T and the LHC centre-of-mass energy. We present the flavour decomposition of the initial-state partons and an evaluation of the theoretical uncertainties. We also show that the W + /W - ratio is sensitive to the up-quark to down-quark ratio of parton distribution functions (PDFs), while other theoreticalmore » uncertainties are negligible, meaning that a precise measurement of the W + /W - ratio at large boson p T values could constrain the PDFs at larger momentum fractions x than the usual inclusive W charge asymmetry. The W ± /Z ratio is insensitive to PDFs and most other theoretical uncertainties, other than possibly electroweak corrections, and a precise measurement will therefore be useful in validating theoretical predictions needed in data-driven methods, such as using W (→ ℓν) + jets events to estimate the Z(→ νν¯) + jets background in searches for new physics at the LHC. Furthermore, the differential W and Z cross sections themselves, dσ/dp T , have the potential to constrain the gluon distribution, provided that theoretical uncertainties from higher-order QCD and electroweak corrections are brought under control, such as by inclusion of anticipated next-to-next-to-leading order QCD corrections.« less
Electron ionization cross-section calculations for liquid water at high impact energies
NASA Astrophysics Data System (ADS)
Bousis, C.; Emfietzoglou, D.; Hadjidoukas, P.; Nikjoo, H.; Pathak, A.
2008-04-01
Cross-sections for the ionization of liquid water is perhaps the most essential set of data needed for modeling electron transport in biological matter. The complexity of ab initio calculations for any multi-electron target has led to largely heuristic semi-empirical models which take advantage elements of the Bethe, dielectric and binary collision theories. In this work we present various theoretical models for calculating total ionization cross-sections (TICSs) for liquid water over the 10 keV-1 MeV electron energy range. In particular, we extend our recent dielectric model calculations for liquid water to relativistic energies using both the appropriate kinematic corrections and the transverse part. Comparisons are made with widely used atomic and molecular TICS models such as those of Khare and co-workers, Kim-Rudd, Deutsch-Märk, Vriens and Gryzinski. The required dipole oscillator strength was provided by our recent optical-data model which is based on the latest experimental data for liquid water. The TICSs computed by the above models differ by up to 40% from the dielectric results. The best agreement (to within ∼10%) was obtained by Khare's original model and an approximate form of Gryzinski's model. In contrast, the binary-encounter-dipole (BED) models of both Kim-Rudd and Khare and co-workers resulted in ∼10-20% higher TICS values, while discrepancies increased to ∼30-40% when their simpler binary-encounter-Bethe (BEB) versions were used. Finally, we discuss to what extent the accuracy of the TICS is indicative of the reliability of the underlying differential cross-sections.
Asmar, Melissa; Wachtel, Heather; Yan, Yan; Fraker, Douglas L; Cohen, Debbie; Trerotola, Scott O
2015-08-01
Adrenal venous sampling (AVS) is the definitive evaluation for primary aldosteronism (PA). Pre-AVS cross-sectional imaging does not reduce the need for AVS. The goal of this study was to examine whether performing AVS prior to imaging could decrease the use of imaging in the evaluation of PA at a high volume, experienced center. We performed a retrospective analysis of all AVS procedures (n = 337) done for PA from 2001-2013. Patients whose cross-sectional imaging reports were unavailable (n = 90) or AVS was non-diagnostic (n = 12) were excluded. AVS was performed using modified Mayo technique. Univariate analysis utilized the χ² test and fisher's exact test. Of the 235 patients analyzed, 63% (n = 148) were male. The mean age was 55 ± 11 years. AVS was non-lateralizing in 43% (n = 101); these patients might have avoided imaging with an AVS-first approach. Imaging and AVS were concordant in 52% (n = 123). In patients ≤40yo (n = 23), 35% (n = 8) had no lateralization on AVS, and might have avoided imaging in an AVS-first approach. Imaging and AVS were concordant in 52% (n = 12) of patients ≤ 40yo, versus 52% (n = 111) of patients > 40 yo (P = 0.987). An AVS-first, imaging-second approach could have avoided CT/MRI in 43% of patients. At a high volume, experienced center, performing AVS first on patients with PA may reduce unnecessary cross-sectional imaging studies. © 2015 Wiley Periodicals, Inc.
An investigation of MCNP6.1 beryllium oxide S(α, β) cross sections
Sartor, Raymond F.; Glazener, Natasha N.
2016-03-08
In MCNP6.1, materials are constructed by identifying the constituent isotopes (or elements in a few cases) individually. This list selects the corresponding microscopic cross sections calculated from the free-gas model to create the material macroscopic cross sections. Furthermore, the free-gas model and the corresponding material macroscopic cross sections assume that the interactions of atoms do not affect the nuclear cross sections.
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.
Teacher Time Spent on Student Health Issues and School Nurse Presence
ERIC Educational Resources Information Center
Hill, Nina Jean; Hollis, Marianne
2012-01-01
Elementary school teacher time spent on student health issues and the relationship to school nurse services was the focus of this 2-year study. A cross-sectional design was used to survey traditional and exceptional (special needs) classroom teachers about the time they spent on health issues and their perception of school nurse presence. The…
Surveying Older Adults' Opinions on Housing: Recommendations for Policy
ERIC Educational Resources Information Center
Wagner, Shannon L.; Shubair, Mamdouh M.; Michalos, Alex C.
2010-01-01
There is paucity of research investigating opinions and attitudes of seniors 55 years of age and older in relation to housing accommodation and services sensitive to the needs of the senior population. We describe the results of a cross-sectional survey soliciting opinions and attitudes of seniors with respect to a variety of housing issues…
ERIC Educational Resources Information Center
Kanwit, Matthew; Geeslin, Kimberly L.
2014-01-01
The present study fills a need for investigations of learner and native speaker (NS) interpretation of the Spanish subjunctive in contexts that allow variation. The analysis compares responses by NSs and three levels of learners on a written interpretation task in which each item contained a temporal indicator ("cuando" "when",…
Parental Education Level Positively Affects Self-Esteem of Turkish Adolescents
ERIC Educational Resources Information Center
Sahin, Ertugrul; Barut, Yasar; Ersanli, Ercüment
2013-01-01
Although the literature on self-esteem has a long and prolific history in Turkey regarding which demographics may influence the self-esteem of adolescents. The research findings are intricate and undermine the need of further research in Turkey. This cross-sectional study re-examined the effects of age, grade level and education level of a mother…
Background: The relationship between traffic-related air pollution (TRAP) and risk factors for cardiovascular disease needs to be better understood in order to address the adverse impact o.f air pollution on human health.Objective: We examined associations between roadway proximi...
ERIC Educational Resources Information Center
Goodboy, Alan K.
2017-01-01
For decades, instructional communication scholars have relied predominantly on cross-sectional survey methods to generate empirical associations between effective teaching and student learning. These studies typically correlate students' perceptions of their instructor's teaching behaviors with subjective self-report assessments of their own…
Evaluation of the Effects of Vocational Choice and Practical Training on Students' Employability
ERIC Educational Resources Information Center
Kagaari, James R. K.
2007-01-01
Purpose: The purpose of this article is to demonstrate the need for Kyambogo to pay special attention to students' vocational choices, university based training and employability. Design/methodology/approach: The sample of 46 final year students, 90 graduates and 50 supervisors using cross sectional survey design was used to collect data.…
Computer Self-Efficacy of Patients in Urban Health Centers for Web-Based Health Education
ERIC Educational Resources Information Center
Leung, Margaret P.
2014-01-01
Internet-based health information has become increasingly important for ensuring health equity for all populations. The lack of studies reporting on Internet use among patients of public health clinics has obscured the needs of diverse patient groups. Guided by social cognitive theory, this quantitative cross-sectional study used a 30-question…
ERIC Educational Resources Information Center
Shaikh, Ulfat; Nettiksimmons, Jasmine; Romano, Patrick
2011-01-01
Objective: To determine health care provider needs related to pediatric obesity management in rural California and to explore strategies to improve care through telehealth. Methods: Cross-sectional survey of health care providers who treated children and adolescents at 41 rural clinics with existing telehealth connectivity. Results: Most of the…
ERIC Educational Resources Information Center
Galloway, Kelli R.; Bretz, Stacey Lowery
2015-01-01
Research on laboratory learning points to the need to better understand what and how students learn in the undergraduate chemistry laboratory. The Meaningful Learning in the Laboratory Instrument (MLLI) was administered to general and organic chemistry students from 15 colleges and universities across the United States in order to measure the…
Examining the Need for a Code of Conduct in New Jersey Teacher Union Contracts
ERIC Educational Resources Information Center
Guarneri, Cristina M.
2009-01-01
The purpose of this cross-sectional, comparison study attempted to investigate if a code of conduct existed in New Jersey teacher union contracts to nursing/hospital union contracts. Archived data of public school district and nursing/hospital union contracts held with the New Jersey Public Employment Relations Committee (NJ PERC) and Health…
Continuing Education of Nurses in Lebanon: Evaluation and Unmet Needs
ERIC Educational Resources Information Center
Salameh, Pascale R.; Barbour, Bernadette
2006-01-01
In the nursing profession it is necessary for a nurse to engage in continuing education to keep up to date. In Lebanon efforts to establish such continuing education are being made. However, a cross-sectional study conducted on a representative sample of 254 nurses found that 60 per cent attend an insufficient number of continuing education…
ERIC Educational Resources Information Center
Frederick, Heidi R.; Wood, James A.; West, George R.; Winston, Bruce E.
2016-01-01
One salient aspect of authentic leadership is the possibility that it can be developed (Walumbwa, Avolio, Gardner, Wernsing, & Peterson, 2008). However, the relative paucity of research on authentic leadership as a dependent variable needs to be addressed. The purpose of this cross-sectional quantitative study is to examine the three factors…
Ryder, Robert T.; Swezey, Christopher S.; Crangle, Robert D.; Trippi, Michael H.
2008-01-01
Geologic cross section E-E' is the first in a series of cross sections planned by the U.S. Geological Survey (USGS) to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section E-E' provides a regional view of the structural and stratigraphic framework of the basin from the Findlay arch in northwestern Ohio to the Valley and Ridge province in eastern West Virginia, a distance of approximately 380 miles (mi) (fig. 1, on sheet 1). Cross section E-E' updates earlier geologic cross sections through the central Appalachian basin by Renfro and Feray (1970), Bennison (1978), and Bally and Snelson (1980) and a stratigraphic cross section by Colton (1970). Although other published cross sections through parts of the basin show more structural detail (for example, Shumaker, 1985; Kulander and Dean, 1986) and stratigraphic detail (for example, Ryder, 1992; de Witt and others, 1993; Hettinger, 2001), these other cross sections are of more limited extent geographically and stratigraphically. Although specific petroleum systems in the Appalachian basin are not identified on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and preferred migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on information shown on the cross section. Cross section E-E' lacks the detail to illustrate key elements of coal systems (such as paleoclimate, coal quality, and coal rank), but it does provide a general framework (stratigraphic units and general rock types) for the coal-bearing section. Also, cross section E-E' may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste (for example, Colton, 1961; Lloyd and Reid, 1990) or for the sequestration of carbon dioxide (for example, Smith and others, 2002; Lucier and others, 2006).
Optimization of Production Lines and Cross-sections of Fiberglass Rebar
NASA Astrophysics Data System (ADS)
Maksimov, S. P.; Dildin, A. N.; Maksimova, A. E.
2017-11-01
The article substantiates the need of the construction industry in new lightweight and durable materials that ensure reduction in the cost of work and increase in the operational characteristics of the constructed facilities. These materials include fiberglass reinforcement which is an auxiliary bar made of heavy-duty glass fibers impregnated with a polymer adhesive composition and additionally entwined to create a ribbed surface and tight fit with fiberglass threads. This fitting has undeniable advantages in comparison with steel fittings. The polymer composite is resistant to corroding medium, does not corrode, does not conduct electricity, has high elastic properties, low thermal conductivity, increased tensile strength, etc. It is shown that the issues related to the improvement of technology and the form of a fiberglass rebar section are relevant for the construction industry. So, in particular, the presented developments will significantly reduce the consumption of adhesive composition for impregnating roving threads, reduce production costs by eliminating the loss of adhesive composition in impregnating vessels and pull-guide rollers, increasing the environmental friendliness of production and increasing the line productivity. In addition, it is possible to improve the strength characteristics by optimizing the cross-section and longitudinal cross-sections of the resulting fiberglass reinforcement. The presented changes in the design and technology of fiberglass reinforcement production can be realized as a separate independent module. It is easy to integrate into existing lines during repair work or routine maintenance of equipment.
Weaknesses in the reporting of cross-sectional studies according to the STROBE statement
Malaga, German; Miranda, Jaime
2015-01-01
Introduction: The inadequate reporting of cross-sectional studies, as in the case of the prevalence of metabolic syndrome, could cause problems in the synthesis of new evidence and lead to errors in the formulation of public policies. Objective: To evaluate the reporting quality of the articles regarding metabolic syndrome prevalence in Peruvian adults using the STROBE recommendations. Methods: We conducted a thorough literature search with the terms "Metabolic Syndrome", "Sindrome Metabolico" and "Peru" in MEDLINE/PubMed, LILACS, SciELO, LIPECS and BVS-Peru until December 2014. We selected those who were population-based observational studies with randomized sampling that reported prevalence of metabolic syndrome in adults aged 18 or more of both sexes. Information was analysed through the STROBE score per item and recommendation. Results: Seventeen articles were included in this study. All articles met the recommendations related to the report of the study's rationale, design, and provision of summary measures. The recommendations with the lowest scores were those related to the sensitivity analysis (8%, n= 1/17), participant flowchart (18%, n= 3/17), missing data analysis (24%, n= 4/17), and number of participants in each study phase (24%, n= 4/17). Conclusion: Cross-sectional studies regarding the prevalence of metabolic syndrome in peruvian adults have an inadequate reporting on the methods and results sections. We identified a clear need to improve the quality of such studies. PMID:26848197
Tapia, Jose Carlos; Ruiz, Eloy F; Ponce, Oscar J; Malaga, German; Miranda, Jaime
2015-12-30
The inadequate reporting of cross-sectional studies, as in the case of the prevalence of metabolic syndrome, could cause problems in the synthesis of new evidence and lead to errors in the formulation of public policies. To evaluate the reporting quality of the articles regarding metabolic syndrome prevalence in Peruvian adults using the STROBE recommendations. We conducted a thorough literature search with the terms "Metabolic Syndrome", "Sindrome Metabolico" and "Peru" in MEDLINE/PubMed, LILACS, SciELO, LIPECS and BVS-Peru until December 2014. We selected those who were population-based observational studies with randomized sampling that reported prevalence of metabolic syndrome in adults aged 18 or more of both sexes. Information was analysed through the STROBE score per item and recommendation. Seventeen articles were included in this study. All articles met the recommendations related to the report of the study's rationale, design, and provision of summary measures. The recommendations with the lowest scores were those related to the sensitivity analysis (8%, n= 1/17), participant flowchart (18%, n= 3/17), missing data analysis (24%, n= 4/17), and number of participants in each study phase (24%, n= 4/17). Cross-sectional studies regarding the prevalence of metabolic syndrome in peruvian adults have an inadequate reporting on the methods and results sections. We identified a clear need to improve the quality of such studies.
A comparison of total reaction cross section models used in particle and heavy ion transport codes
NASA Astrophysics Data System (ADS)
Sihver, Lembit; Lantz, M.; Takechi, M.; Kohama, A.; Ferrari, A.; Cerutti, F.; Sato, T.
To be able to calculate the nucleon-nucleus and nucleus-nucleus total reaction cross sections with precision is very important for studies of basic nuclear properties, e.g. nuclear structure. This is also of importance for particle and heavy ion transport calculations because, in all particle and heavy ion transport codes, the probability function that a projectile particle will collide within a certain distance x in the matter depends on the total reaction cross sections. Furthermore, the total reaction cross sections will also scale the calculated partial fragmentation cross sections. It is therefore crucial that accurate total reaction cross section models are used in the transport calculations. In this paper, different models for calculating nucleon-nucleus and nucleus-nucleus total reaction cross sections are compared and discussed.
Vertically stabilized elongated cross-section tokamak
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.
Rao, Danish Ahmed; Aman, Aiysha; Muhammad Mubeen, Syed; Shah, Ahmed
2017-07-01
Stethoscopes routinely used for clinical examination of patients may potentially transfer micro-organisms and cause iatrogenic infections. This study was undertaken to detect the presence of microorganisms on stethoscopes used clinically in hospitals of Karachi, Pakistan and to ascertain the infection control practices of healthcare workers (HCWs). In a cross-sectional study, 118 samples were collected from public and private institutions. Samples were tested for the presence and sensitivity of pathogenic microorganisms. Microorganisms were found on diaphragms of 33/64 (51.6%) and 19/57 (33.3%) stethoscopes in public and private sector hospitals, respectively. Methycillin resistance was identified in all staphylococcally contaminated samples. Only 33 (18%) respondents reported cleaning their stethoscopes regularly. We highlight the need for more and better on-the-job routines for decontaminating stethoscopes among HCWs in Karachi.
Prevalence of Autism Spectrum Disorder in Nurseries in Lebanon: A Cross Sectional Study.
Chaaya, Monique; Saab, Dahlia; Maalouf, Fadi T; Boustany, Rose-Mary
2016-02-01
In Lebanon, no estimate for autism prevalence exists. This cross-sectional study examines the prevalence of Autism spectrum disorder (ASD) in toddlers in nurseries in Beirut and Mount-Lebanon. The final sample included 998 toddlers (16-48 months) from 177 nurseries. We sent parents the Modified Checklist for Autism in Toddlers (M-CHAT) for screening, and a self-administered questionnaire (associated factors). We imputed missing M-CHAT data with successful answers. Since there were no follow-up interviews for the M-CHAT, we used the positive predictive value (0.058) from a large study for prevalence estimates. ASD prevalence was 1 in 66 children (comparable to US). Ratios were: male/female: 1.05; Beirut/Mount-Lebanon: 1.2. Using a more representative sample and ascertaining results are needed for better prevalence estimates in Lebanon.
Milner, Allison; Page, Kathryn; Witt, Katrina; LaMontagne, Anthony
2016-06-01
This study examined the relationship between psychosocial working factors such as job control, job demands, job insecurity, supervisor support, and workplace bullying as risk factors for suicide ideation. We used a logistic analytic approach to assess risk factors for thoughts of suicide in a cross-sectional sample of working Australians. Potential predictors included psychosocial job stressors (described above); we also controlled for age, gender, occupational skill level, and psychological distress. We found that workplace bullying or harassment was associated with 1.54 greater odds of suicide ideation (95% confidence interval 1.64 to 2.05) in the model including psychological distress. Results also suggest that higher job control and security were associated with lower odds of suicide ideation. These results suggest the need for organizational level intervention to address psychosocial job stressors, including bullying.
Deodhar, Jayita Kedar; Muckaden, Mary Ann
2015-01-01
Training programs for volunteers prior to their working in palliative care are well-established in India. However, few studies report on continuing professional development programs for this group. To conduct a preliminary assessment of educational needs of volunteers working in palliative care for developing a structured formal continuing professional development program for this group. Cross-sectional observational study conducted in the Department of Palliative Medicine of a tertiary care cancer institute in India. Participant volunteers completed a questionnaire, noting previous training, years of experience, and a comprehensive list of topics for inclusion in this program, rated in order of importance according to them. Descriptive statistics for overall data and Chi-square tests for categorical variables for group comparisons were applied using Statistical Package for Social Sciences version 18. Fourteen out of 17 volunteers completed the questionnaire, seven having 5-10-years experience in working in palliative care. A need for continuing professional development program was felt by all participants. Communication skills, more for children and elderly specific issues were given highest priority. Spiritual-existential aspects and self-care were rated lower in importance than psychological, physical, and social aspects in palliative care. More experienced volunteers (>5 years of experience) felt the need for self-care as a topic in the program than those with less (<5-years experience) (P < 0.05). Understanding palliative care volunteers' educational needs is essential for developing a structured formal continuing professional development program and should include self-care as a significant component.
BACKSCAT Lidar Simulation Version 3.0: Technical Documentation and Users Guide
1992-12-03
Raman Cross Section of Some Simple Gases, J. Opt. Soc. Am., 63:73. 20 Penny, C.M., St. Peters, R.L., and Lapp, M., (1974) Absolute Rotational Raman...of the molecule, and the remaining columns list the relative normalized cross sections for the respective excitation wavelength. The absolute Raman...cross section is obtained by simply multiplying the relative normalized cross section for a molecular species of interest by the absolute cross section
A FODO racetrack ring for nuSTORM: design and optimization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, A.; Bross, A.; Neuffer, D.
2017-07-01
The goal of nuSTORM is to provide well-defined neutrino beams for precise measurements of neutrino cross-sections and oscillations. The nuSTORM decay ring is a compact racetrack storage ring with a circumference of ~ 480 m that incorporates large aperture (60 cm diameter) magnets. There are many challenges in the design. In order to incorporate the Orbit Combination section (OCS), used for injecting the pion beam into the ring, a dispersion suppressor is needed adjacent to the OCS . Concurrently, in order to maximize the number of useful muon decays, strong bending dipoles are needed in the arcs to minimize the arcmore » length. These dipoles create strong chromatic effects, which need to be corrected by nonlinear sextupole elements in the ring. In this paper, a FODO racetrack ring design and its optimization using sextupolar fields via both a Genetic Algorithm (GA) and a Simulated Annealing (SA) algorithm will be discussed.« less
Energy and Mass-Number Dependence of Hadron-Nucleus Total Reaction Cross Sections
NASA Astrophysics Data System (ADS)
Kohama, Akihisa; Iida, Kei; Oyamatsu, Kazuhiro
2016-09-01
We thoroughly investigate how proton-nucleus total reaction cross sections depend on the target mass number A and the proton incident energy. In doing so, we systematically analyze nuclear reaction data that are sensitive to nuclear size, namely, proton-nucleus total reaction cross sections and differential elastic cross sections, using a phenomenological black-sphere approximation of nuclei that we are developing. In this framework, the radius of the black sphere is found to be a useful length scale that simultaneously accounts for the observed proton-nucleus total reaction cross section and first diffraction peak in the proton elastic differential cross section. This framework, which is shown here to be applicable to antiprotons, is expected to be applicable to any kind of projectile that is strongly attenuated in the nucleus. On the basis of a cross-section formula constructed within this framework, we find that a less familiar A1/6 dependence plays a crucial role in describing the energy dependence of proton-nucleus total reaction cross sections.
Activation cross section and isomeric cross-section ratio for the 151Eu(n,2n)150m,gEu process
NASA Astrophysics Data System (ADS)
Luo, Junhua; Li, Suyuan; Jiang, Li
2018-07-01
The cross sections of 151Eu(n,2n)150m,gEu reactions and their isomeric cross section ratios σm/σt have been measured experimentally. Cross sections are measured, relative to a reference 93Nb(n,2n)92mNb reaction cross section, by means of the activation technique at three neutron energies 13.5, 14.1, and 14.8 MeV. Monoenergetic neutron beams were formed via the 3H(d,n)4He reaction and both Eu2O3 samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The activities induced in the reaction products were measured using high-resolution gamma ray spectroscopy. Cross sections were also evaluated theoretically using the numerical nuclear model code, TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.
Total reaction cross sections in CEM and MCNP6 at intermediate energies
Kerby, Leslie M.; Mashnik, Stepan G.
2015-05-14
Accurate total reaction cross section models are important to achieving reliable predictions from spallation and transport codes. The latest version of the Cascade Exciton Model (CEM) as incorporated in the code CEM03.03, and the Monte Carlo N-Particle transport code (MCNP6), both developed at Los Alamos National Laboratory (LANL), each use such cross sections. Having accurate total reaction cross section models in the intermediate energy region (50 MeV to 5 GeV) is very important for different applications, including analysis of space environments, use in medical physics, and accelerator design, to name just a few. The current inverse cross sections used inmore » the preequilibrium and evaporation stages of CEM are based on the Dostrovsky et al. model, published in 1959. Better cross section models are now available. Implementing better cross section models in CEM and MCNP6 should yield improved predictions for particle spectra and total production cross sections, among other results.« less
Total reaction cross sections in CEM and MCNP6 at intermediate energies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kerby, Leslie M.; Mashnik, Stepan G.
Accurate total reaction cross section models are important to achieving reliable predictions from spallation and transport codes. The latest version of the Cascade Exciton Model (CEM) as incorporated in the code CEM03.03, and the Monte Carlo N-Particle transport code (MCNP6), both developed at Los Alamos National Laboratory (LANL), each use such cross sections. Having accurate total reaction cross section models in the intermediate energy region (50 MeV to 5 GeV) is very important for different applications, including analysis of space environments, use in medical physics, and accelerator design, to name just a few. The current inverse cross sections used inmore » the preequilibrium and evaporation stages of CEM are based on the Dostrovsky et al. model, published in 1959. Better cross section models are now available. Implementing better cross section models in CEM and MCNP6 should yield improved predictions for particle spectra and total production cross sections, among other results.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, Suvam; Naghma, Rahla; Kaur, Jaspreet
The total and ionization cross sections for electron scattering by benzene, halobenzenes, toluene, aniline, and phenol are reported over a wide energy domain. The multi-scattering centre spherical complex optical potential method has been employed to find the total elastic and inelastic cross sections. The total ionization cross section is estimated from total inelastic cross section using the complex scattering potential-ionization contribution method. In the present article, the first theoretical calculations for electron impact total and ionization cross section have been performed for most of the targets having numerous practical applications. A reasonable agreement is obtained compared to existing experimental observationsmore » for all the targets reported here, especially for the total cross section.« less
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.
Rubin, G James; Page, Lisa; Morgan, Oliver; Pinder, Richard J; Riley, Paul; Hatch, Stephani; Maguire, Helen; Catchpole, Mike; Simpson, John; Wessely, Simon
2007-12-01
To identify public perceptions of the risk to health after the poisoning of Alexander Litvinenko with polonium-210 (210Po) in London and to assess the impact of public health communications. Cross sectional telephone survey and qualitative interviews. London, United Kingdom. 1000 people completed the cross sectional survey and 86 potentially exposed people completed the qualitative interviews. Perception of risk to personal health after the 210Po incident. Qualitative interviews were analysed with an emphasis on information needs. 11.7% of the survey sample (n=117) perceived their health to be at risk. Aside from personal variables the main predictors of perceived risk to health were believing that the incident was related to terrorism (odds ratio 2.7, 95% confidence interval 1.5 to 4.6) rather than to espionage, that it was targeted at the wider public rather than one person (5.9, 3.2 to 10.9), and that it could affect people who had not been in the contaminated area (3.2, 2.1 to 5.1). Participants in the qualitative interviews were generally satisfied with the information they had received, although they would have preferred more information about their individual risk of exposure, the results of their urine tests, and the health implications of the incident. Perceptions of the public that the 210Po incident in London in 2006 was related to espionage helped to reassure them that the risks to personal health were low. In the event of future incidents it is important to ensure that detailed, comprehensible information about the risks of any exposure is available.
Page, Lisa; Morgan, Oliver; Pinder, Richard J; Riley, Paul; Hatch, Stephani; Maguire, Helen; Catchpole, Mike; Simpson, John; Wessely, Simon
2007-01-01
Objectives To identify public perceptions of the risk to health after the poisoning of Alexander Litvinenko with polonium-210 (210Po) in London and to assess the impact of public health communications. Design Cross sectional telephone survey and qualitative interviews. Setting London, United Kingdom. Participants 1000 people completed the cross sectional survey and 86 potentially exposed people completed the qualitative interviews. Main outcome measures Perception of risk to personal health after the 210Po incident. Qualitative interviews were analysed with an emphasis on information needs. Results 11.7% of the survey sample (n=117) perceived their health to be at risk. Aside from personal variables the main predictors of perceived risk to health were believing that the incident was related to terrorism (odds ratio 2.7, 95% confidence interval 1.5 to 4.6) rather than to espionage, that it was targeted at the wider public rather than one person (5.9, 3.2 to 10.9), and that it could affect people who had not been in the contaminated area (3.2, 2.1 to 5.1). Participants in the qualitative interviews were generally satisfied with the information they had received, although they would have preferred more information about their individual risk of exposure, the results of their urine tests, and the health implications of the incident. Conclusions Perceptions of the public that the 210Po incident in London in 2006 was related to espionage helped to reassure them that the risks to personal health were low. In the event of future incidents it is important to ensure that detailed, comprehensible information about the risks of any exposure is available. PMID:17975252
Mick, Paul; Parfyonov, Maksim; Wittich, Walter; Phillips, Natalie; Kathleen Pichora-Fuller, M
2018-01-01
To determine if hearing loss, vision loss, and dual sensory loss were associated with social network diversity, social participation, availability of social support, and loneliness, respectively, in a population-based sample of older Canadians and to determine whether age or sex modified the associations. Cross-sectional population-based study. Canada. The sample included 21 241 participants in the Canadian Longitudinal Study on Aging tracking cohort. The sample was nationally representative of English- and French-speaking, non-institutionalized 45- to 89-year-old Canadians who did not live on First Nations reserves and who had normal cognition. Participants with missing data for any of the variables in the multivariable regression models were excluded from analysis. Hearing and vision loss were determined by self-report. Dual sensory loss was defined as reporting both hearing and vision loss. Univariate analyses were performed to assess cross-sectional associations between hearing, vision, and dual sensory loss, and social, demographic, and medical variables. Multivariable regression models were used to analyze cross-sectional associations between each type of sensory loss and social network diversity, social participation, availability of social support, and loneliness. Vision loss (in men) and dual sensory loss (in 65- to 85-year-olds) were independently associated with reduced social network diversity. Vision loss and dual sensory loss (in 65- to 85-year-olds) were each independently associated with reduced social participation. All forms of sensory loss were associated with both low availability of social support and loneliness. Sensory impairment is associated with reduced social function in older Canadians. Interventions and research that address the social needs of older individuals with sensory loss are needed. Copyright© the College of Family Physicians of Canada.
Almoosawi, S; Vingeliene, S; Karagounis, L G; Pot, G K
2016-11-01
The importance of the circadian rhythm in regulating human food intake behaviour and metabolism has long been recognised. However, little is known as to how energy intake is distributed over the day in existing populations, and its potential association with obesity. The present review describes global trends in time-of-day of energy intake in the general population based on data from cross-sectional surveys and longitudinal cohorts. Evidence of the association between time-of-day of energy intake and obesity is also summarised. Overall, there were a limited number of cross-sectional surveys and longitudinal cohorts that provided data on time-of-day of energy intake. In the identified studies, a wide variation in time-of-day of energy intake was observed, with patterns of energy distribution varying greatly by country and geographical area. In relation to obesity, eight cross-sectional surveys and two longitudinal cohorts were identified. The association between time-of-day of energy intake and obesity varied widely, with several studies reporting a positive link between evening energy intake and obesity. In conclusion, the current review summarises global trends in time-of-day of energy intake. The large variations across countries and global regions could have important implications to health, emphasising the need to understand the socio-environmental factors guiding such differences in eating patterns. Evidence of the association between time-of-day of energy intake and BMI also varied. Further larger scale collaborations between various countries and regions are needed to sum data from existing surveys and cohorts, and guide our understanding of the role of chrono-nutrition in health.
Nano, J; Muka, T; Cepeda, M; Voortman, T; Dhana, K; Brahimaj, A; Dehghan, A; Franco, O H
2016-12-01
Emerging evidence suggests that bilirubin levels might be associated with the metabolic syndrome (MetS) and type 2 diabetes (T2D), although the nature of the association remains unclear. This systematic review and meta-analysis investigated the relationship between total plasma bilirubin and the risk of MetS and T2D. Relevant studies were identified using five databases (Embase, Medline [Ovid], Web of Science, PubMed, Cochrane Central and Google Scholar), with the last search done on 21 October 2015. Study references were checked and authors contacted to identify additional studies. Randomized controlled trials, and cohort, case-control and cross-sectional studies of adults examining the association between blood bilirubin levels and MetS and T2D were included, irrespective of language and date of publication. Abstract and full-text selection was done by two independent reviewers, with a third reviewer available in case of disagreement. Data were extracted by two independent reviewers using a predesigned data collection form. MetS and T2D. Summary estimates were obtained by random-effects meta-analysis. Of the 2313 searched references, 16 observational studies (11 cross-sectional, two prospective, one that was both cross-sectional and prospective, two retrospective and one national survey) met our inclusion criteria. Overall, data were available for 175,911 non-overlapping participants, including 7414 MetS cases and 9406 T2D cases. In the meta-analysis of seven cross-sectional studies, the pooled odds ratio (95% confidence interval) for MetS in a comparison of extreme tertiles of serum bilirubin levels was 0.70 (95% CI: 0.62, 0.78), whereas no significant association was found for the pooled estimated relative risk between two prospective studies (0.57, 95% CI: 0.11, 2.94). The corresponding estimate was 0.77 (95% CI: 0.67, 0.87) for T2D from four cross-sectional studies. The available evidence, mainly from cross-sectional studies, supports an inverse association of bilirubin levels with adverse metabolic outcomes. Large-scale prospective studies are now needed to establish whether bilirubin levels may be useful in the prevention of MetS and T2D. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Cross sections for direct and dissociative ionization of NH3 and CS2 by electron impact
NASA Technical Reports Server (NTRS)
Rao, M. V. V. S.; Srivastava, S. K.
1991-01-01
A crossed electron beam-molecular beam collision geometry is used to measure cross sections for the production of positive ions by electron impact on NH3 and CS2. Ionization cross-section data for NH3 and the values of various cross sections are presented, as well as ionization efficiency curves for CS2. Considerable differences are found between the various results on NH3. The present values are close to the data of Djuric et al. (1981). The semiempirical calculations of Hare and Meath (1987) differ considerably in the absolute values of cross sections. Discrepancies were observed in comparisons of cross sections of other fragment ions resulting from the ionization and dissociate ionization of NH3.
NASA Astrophysics Data System (ADS)
Sauerwein, A.; Endres, J.; Netterdon, L.; Zilges, A.; Foteinou, V.; Provatas, G.; Konstantinopoulos, T.; Axiotis, M.; Ashley, S. F.; Harissopulos, S.; Rauscher, T.
2012-09-01
Background: Astrophysical models studying the origin of the neutron-deficient p nuclides require knowledge of proton capture cross sections at low energy. The production site of the p nuclei is still under discussion but a firm basis of nuclear reaction rates is required to address the astrophysical uncertainties. Data at astrophysically relevant interaction energies are scarce. Problems with the prediction of charged particle capture cross sections at low energy were found in the comparisons between previous data and calculations in the Hauser-Feshbach statistical model of compound reactions.Purpose: A measurement of 74Ge(p,γ)75As at low proton energies, inside the astrophysically relevant energy region, is important in several respects. The reaction is directly important because it is a bottleneck in the reaction flow which produces the lightest p nucleus 74Se. It is also an important addition to the data set required to test reaction-rate predictions and to allow an improvement in the global p+nucleus optical potential required in such calculations.Method: An in-beam experiment was performed, making it possible to measure in the range 2.1≤Ep≤3.7MeV, which is for the most part inside the astrophysically relevant energy window. Angular distributions of the γ-ray transitions were measured with high-purity germanium detectors at eight angles relative to the beam axis. In addition to the total cross sections, partial cross sections for the direct population of 12 levels were determined.Results: The resulting cross sections were compared to Hauser-Feshbach calculations using the code smaragd. Only a constant renormalization factor of the calculated proton widths allowed a good reproduction of both total and partial cross sections. The accuracy of the calculation made it possible to check the spin assignment of some states in 75As. In the case of the 1075-keV state, a double state with spins and parities of 3/2- and 5/2- is needed to explain the experimental partial cross sections. A change in parity from 5/2+ to 5/2- is required for the state at 401 keV. Furthermore, in the case of 74Ge, studying the combination of total and partial cross sections made it possible to test the γ width, which is essential in the calculation of the astrophysical 74As(n,γ)75As rate.Conclusions: Between data and statistical model prediction a factor of about two was found. Nevertheless, the improved astrophysical reaction rate of 74Ge(p,γ) (and its reverse reaction) is only 28% larger than the previous standard rate. The prediction of the 74As(n,γ)75As rate (and its reverse) was confirmed, the newly calculated rate differs only by a few percent from the previous prediction. The in-beam method with high-efficiency detectors proved to be a powerful tool for studies in nuclear astrophysics and nuclear structure.
Nuclear Forensics and Radiochemistry: Cross Sections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rundberg, Robert S.
The neutron activation of components in a nuclear device can provide useful signatures of weapon design or sophistication. This lecture will cover some of the basics of neutron reaction cross sections. Nuclear reactor cross sections will also be presented to illustrate the complexity of convolving neutron energy spectra with nuclear excitation functions to calculate useful effective reactor cross sections. Deficiencies in the nuclear database will be discussed along with tools available at Los Alamos to provide new neutron cross section data.
Fragmentation Cross Sections of Medium-Energy 35Cl, 40Ar, and 48TiBeams on Elemental Targets
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zeitlin, C.; Guetersloh, S.; Heilbronn, L.
Charge-changing and fragment production cross sections at 0degrees have been obtained for interactions of 290, 400, and 650MeV/nucleon 40Ar beams, 650 and 1000 MeV/nucleon 35Cl beams, and a 1000MeV/nucleon 48Ti beam. Targets of C, CH2, Al, Cu, Sn, and Pb were used.Using standard analysis methods, we obtain fragment cross sections forcharges as low as 8 for Cl and Ar beams, and as low as 10 for the Tibeam. Using data obtained with small-acceptance detectors, we reportfragment production cross sections for charges as low as 5, corrected foracceptance using a simple model of fragment angular distributions. Withthe lower-charged fragment cross sections,more » we cancompare the data topredictions from several models (including NUCFRG2, EPAX2, and PHITS) ina region largely unexplored in earlier work. As found in earlier workwith other beams, NUCFRG2 and PHITS predictions agree reasonably wellwith the data for charge-changing cross sections, but do not accuratelypredict the fragment production cross sections. The cross sections forthe lightest fragments demonstrate the inadequacy of several models inwhich the cross sections fall monotonically with the charge of thefragment. PHITS, despite not agreeing particularly well with the fragmentproduction cross sections on average, nonetheless qualitativelyreproduces somesignificant features of the data that are missing from theother models.« less
NASA Technical Reports Server (NTRS)
Yoshino, K.; Esmond, J. R.; Cheung, A. S.-C.; Freeman, D. E.; Parkinson, W. H.
1992-01-01
Results are presented on measurements, conducted in the wavelength region 180-195 nm, and at different pressures of oxygen (between 2.5-760 torr) in order to separate the pressure-dependent absorption from the main cross sections, of the absorption cross sections of the Schumann-Runge bands in the window region between the rotational lines of S-R bands of O2. The present cross sections supersede the earlier published cross sections (Yoshino et al., 1983). The combined cross sections are presented graphically; they are available at wavenumber intervals of about 0.1/cm from the National Space Science Data Center. The Herzberg continuum cross sections are derived after subtracting calculated contributions from the Schumann-Runge bands. These are significantly smaller than any previous measurements.
DOE Office of Scientific and Technical Information (OSTI.GOV)
2015-10-19
CEPXS is a multigroup-Legendre cross-section generating code. The cross sections produced by CEPXS enable coupled electron-photon transport calculations to be performed with multigroup radiation transport codes, e.g. MITS and SCEPTRE. CEPXS generates multigroup-Legendre cross sections for photons, electrons and positrons over the energy range from 100 MeV to 1.0 keV. The continuous slowing-down approximation is used for those electron interactions that result in small-energy losses. The extended transport correction is applied to the forward-peaked elastic scattering cross section for electrons. A standard multigroup-Legendre treatment is used for the other coupled electron-photon cross sections. CEPXS extracts electron cross-section information from themore » DATAPAC data set and photon cross-section information from Biggs-Lighthill data. The model that is used for ionization/relaxation in CEPXS is essentially the same as that employed in ITS.« less
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.
Patients' Care Needs: Documentation Analysis in General Hospitals.
Paans, Wolter; Müller-Staub, Maria
2015-10-01
The purpose of the study is (a) to describe care needs derived from records of patients in Dutch hospitals, and (b) to evaluate whether nurses employed the NANDA-I classification to formulate patients' care needs. A stratified cross-sectional random-sampling nursing documentation audit was conducted employing the D-Catch instrument in 10 hospitals comprising 37 wards. The most prevalent nursing diagnoses were acute pain, nausea, fatigue, and risk for impaired skin integrity. Most care needs were determined in physiological health patterns and few in psychosocial patterns. To perform effective interventions leading to high-quality nursing-sensitive outcomes, nurses should also diagnose patients' care needs in the health management, value-belief, and coping stress patterns. © 2014 NANDA International, Inc.
Ryder, Robert T.; Crangle, Robert D.; Trippi, Michael H.; Swezey, Christopher S.; Lentz, Erika E.; Rowan, Elisabeth L.; Hope, Rebecca S.
2009-01-01
Geologic cross section D-D' is the second in a series of cross sections constructed by the U.S. Geological Survey to document and improve understanding of the geologic framework and petroleum systems of the Appalachian basin. Cross section D-D' provides a regional view of the structural and stratigraphic framework of the Appalachian basin from the Findlay arch in northwestern Ohio to the Valley and Ridge province in eastern West Virginia, a distance of approximately 290 miles. The information shown on the cross section is based on geological and geophysical data from 13 deep drill holes, several of which penetrate the Paleozoic sedimentary rocks of the basin and bottom in Mesoproterozoic (Grenville-age) crystalline basement rocks. This cross section is a companion to cross section E-E' (Ryder and others, 2008) that is located about 25 to 50 mi to the southwest. Although specific petroleum systems in the Appalachian basin are not identified on the cross section, many of their key elements (such as source rocks, reservoir rocks, seals, and traps) can be inferred from lithologic units, unconformities, and geologic structures shown on the cross section. Other aspects of petroleum systems (such as the timing of petroleum generation and preferred migration pathways) may be evaluated by burial history, thermal history, and fluid flow models based on information shown on the cross section. Cross section D-D' lacks the detail to illustrate key elements of coal systems (such as paleoclimate, coal quality, and coal rank), but it does provide a general geologic framework (stratigraphic units and general rock types) for the coal-bearing section. Also, cross section D-D' may be used as a reconnaissance tool to identify plausible geologic structures and strata for the subsurface storage of liquid waste or for the sequestration of carbon dioxide.
Electron impact excitation of SO2 - Differential, integral, and momentum transfer cross sections
NASA Technical Reports Server (NTRS)
Vuskovic, L.; Trajmar, S.
1982-01-01
Electron impact excitation of the electronic states of SO2 was investigated. Differential, integral, and inelastic momentum transfer cross sections were obtained by normalizing the relative measurements to the elastic cross sections. The cross sections are given for seven spectral ranges of the energy-loss spectra extending from the lowest electronic state to near the first ionization limit. Most of the regions represent the overlap of several electronic transitions. No measurements for these cross sections have been reported previously.
NASA Technical Reports Server (NTRS)
Green, T. J.
1973-01-01
Computer programs were used to calculate the total electron excitation cross-section for atoms and the partial ionization cross-section. The approximations to the scattering amplitude used are as follows: (1) Born, Bethe, and Modified Bethe for non-exchange excitation; (2) Ochkur for exchange excitation; and (3) Coulomb-Born of non-exchange ionization. The amplitudes are related to the differential cross-sections which are integrated to give the total excitation (or partial ionization) cross-section for the collision. The atomic wave functions used are Hartree-Fock-Slater functions for bound states and the coulomb wave function for the continuum. The programs are presented and the results are examined.
Electron impact scattering study of hypohalous acids HOX (X = F, Cl, Br, I)
NASA Astrophysics Data System (ADS)
Yadav, Hitesh; Bhutadia, Harshad; Prajapati, Dinesh; Desai, Hardik; Vinodkumar, Minaxi; Vinodkumar, P. C.
2018-05-01
In this article we aim to report total cross sections (TCS) QT, total elastic cross sections (Qel), total inelastic cross sections (Qinel) i.e. (total ionizations cross sections (Qion)+total electronic excitation cross sections (Qexc)) from threshold of the target to 5000 eV energy range. We have used a well-defined theoretical methodology Spherical Complex Optical Potential (SCOP) to compute QT, Qel and Qinel and Complex Scattering Potential - ionization contribution (CSP - ic) method to report the (Qion). The cross-sectional data reported here for the Hypohalous Acids is for the first time and the present data can become a guideline for the experimentalist to study these targets.
Benefits of regular aerobic exercise for executive functioning in healthy populations.
Guiney, Hayley; Machado, Liana
2013-02-01
Research suggests that regular aerobic exercise has the potential to improve executive functioning, even in healthy populations. The purpose of this review is to elucidate which components of executive functioning benefit from such exercise in healthy populations. In light of the developmental time course of executive functions, we consider separately children, young adults, and older adults. Data to date from studies of aging provide strong evidence of exercise-linked benefits related to task switching, selective attention, inhibition of prepotent responses, and working memory capacity; furthermore, cross-sectional fitness data suggest that working memory updating could potentially benefit as well. In young adults, working memory updating is the main executive function shown to benefit from regular exercise, but cross-sectional data further suggest that task-switching and post error performance may also benefit. In children, working memory capacity has been shown to benefit, and cross-sectional data suggest potential benefits for selective attention and inhibitory control. Although more research investigating exercise-related benefits for specific components of executive functioning is clearly needed in young adults and children, when considered across the age groups, ample evidence indicates that regular engagement in aerobic exercise can provide a simple means for healthy people to optimize a range of executive functions.
Nuclear effects in (anti)neutrino charge-current quasielastic scattering at MINER νA kinematics
NASA Astrophysics Data System (ADS)
Ivanov, M. V.; Antonov, A. N.; Megias, G. D.; González-Jiménez, R.; Barbaro, M. B.; Caballero, J. A.; Donnelly, T. W.; Udías, J. M.
2018-05-01
We compare the characteristics of the charged-current quasielastic (anti)neutrino scattering obtained in two different nuclear models, the phenomenological SuperScaling Approximation and the model using a realistic spectral function S(p, ɛ) that gives a scaling function in accordance with the (e, e‧ ) scattering data, with the recent data published by the MiniBooNE, MINER νA, and NOMAD collaborations. The spectral function accounts for the nucleon-nucleon (NN) correlations by using natural orbitals from the Jastrow correlation method and has a realistic energy dependence. Both models provide a good description of the MINER νA and NOMAD data without the need of an ad hoc increase of the value of the mass parameter in the axial-vector dipole form factor. The models considered in this work, based on the the impulse approximation (IA), underpredict the MiniBooNE data for the flux-averaged charged-current quasielastic {ν }μ ({\\bar{ν }}μ ){+}12\\text{C} differential cross section per nucleon and the total cross sections, although the shape of the cross sections is represented by the approaches. The discrepancy is most likely due to missing of the effects beyond the IA, e.g., those of the 2p–2h meson exchange currents that have contribution in the transverse responses.
Xu, Joanna Xiuzhu; Hu, Juan; Zhang, Dongmao
2018-05-25
Presented herein is the ratiometric bandwidth-varied polarized resonance synchronous spectroscopy (BVPRS2) method for quantification of material optical activity spectra. These include the sample light absorption and scattering cross-section spectrum, the scattering depolarization spectrum, and the fluorescence emission cross-section and depolarization spectrum in the wavelength region where the sample both absorbs and emits. This ratiometric BVPRS2 spectroscopic method is a self-contained technique capable of quantitatively decoupling material fluorescence and light scattering signal contribution to its ratiometric BVPRS2 spectra through the linear curve-fitting of the ratiometric BVPRS2 signal as a function of the wavelength bandwidth used in the PRS2 measurements. Example applications of this new spectroscopic method are demonstrated with materials that can be approximated as pure scatterers, simultaneous photon absorbers/emitters, simultaneous photon absorbers/scatterers, and finally simultaneous photon absorbers/scatterers/emitters. Because the only instruments needed for this ratiometric BVPRS2 technique are the conventional UV-vis spectrophotometer and spectrofluorometer, this work should open doors for routine decomposition of material UV-vis extinction spectrum into its absorption and scattering component spectra. The methodology and insights provided in this work should be of broad significance to all chemical research that involves photon/matter interactions.
Religion and body weight: a review of quantitative studies.
Yeary, Karen Hye-Cheon Kim; Sobal, Jeffery; Wethington, Elaine
2017-10-01
Increasing interest in relationships between religion and health has encouraged research about religion and body weight, which has produced mixed findings. We systematically searched 11 bibliographic databases for quantitative studies of religion and weight, locating and coding 85 studies. We conducted a systematic review, analysing descriptive characteristics of the studies as well as relevant religion-body weight associations related to study characteristics. We summarized findings for two categories of religion variables: religious affiliation and religiosity. For religious affiliation, we found evidence for significant associations with body weight in both cross-sectional and longitudinal studies. In particular, Seventh-Day Adventists had lower body weight than other denominations in cross-sectional analyses. For religiosity, significant associations occurred between greater religiosity and higher body weight in both cross-sectional and longitudinal studies. In particular, greater religiosity was significantly associated with higher body weight in bivariate analyses but less so in multivariate analyses. A greater proportion of studies that used a representative sample, longitudinal analyses, and samples with only men reported significant associations between religiosity and weight. Evidence in seven studies suggested that health behaviours and psychosocial factors mediate religion-weight relationships. More longitudinal studies and analyses of mediators are needed to provide stronger evidence and further elucidate religion-weight relationships. © 2017 World Obesity Federation.
Nuclear Astrophysics in underground laboratories: the LUNA experiment
NASA Astrophysics Data System (ADS)
2017-11-01
One of the main ingredients of nuclear astrophysics is the knowledge of the thermonuclear reactions responsible for powering the stellar engine and for the synthesis of the chemical elements. At astrophysical energies the cross section of nuclear processes is extremely reduced by the effect of the Coulomb barrier. The low value of cross sections prevents their measurement at stellar energies on Earth surface and often extrapolations are needed. The Laboratory for Underground Nuclear Astrophysics (LUNA) is placed under the Gran Sasso mountain and thanks to the cosmic-ray background reduction provided by its position can investigate cross sections at energies close to the Gamow peak in stellar scenarios. Many crucial reactions involved in hydrogen burning has been measured directly at astrophysical energies with both the LUNA-50kV and the LUNA-400kV accelerators, and this intense work will continue with the installation of a MV machine able to explore helium and carbon burnings. Based on this progress, currently there are efforts in several countries to construct new underground accelerators. In this talk, the typical techniques adopted in underground nuclear astrophysics will be described and the most relevant results achieved by LUNA will be reviewed. The exciting science that can be probed with the new facilities will be highlighted.
Topics in electron capture by fast ions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsin, S.H.
1987-01-01
The post-collision interaction (PCI) model was applied, together with the eikonal approximation, to study the (n = 2,3) capture cross sections in p + H(ls) collisions. The results indeed improve the previous eikonal calculations for l = 0 cases, and agree quite well with present experimental data. Calculations using the strong-potential Born (SPB) approximation, with the Sil and McGuire technique, for capture into the np, nd levels are also presented. While these cross sections are smaller than cross sections for capture into the ns levels at high velocities, nevertheless the Thomas peak is clearly evident in both the absolute valuemore » m = 2, absolute value m = 1 and m = 0 magnetic substates in p + H(ls) collisions. Also calculated were corrections to the SPB using the Distorted-Wave Born formalism of Taulbjerg and Briggs. In the sense of a plane-wave Born expansion, all terms of the third Born approximation and all single switching fourth Born terms are included, but a peaking approximation is needed to reduce the calculation to tractable form. Effects of the higher terms are most visible in the valley between the Thomas peak and the forward peak. The Thomas peak is visible in the correction term, even though it includes no second Born contributions.« less
NASA Astrophysics Data System (ADS)
Newton, Joseph
Classical novae are explosive binary systems involving the accretion of hydrogen rich material from a main sequence star onto the surface of a white dwarf partner, reaching peak temperatures of T = 0.1-0.4 GK. Observed elemental abundances from the ejecta provide much needed constraints for the modeling of these explosions. Novae are thought to be the most significant source of 15 N and 17 O in the universe. The 17 O(p,g) 18 F and 17 O(p,g) 14 N reactions have an important effect on nucleosynthesis in novae, since they determine the creation and destruction of 17 O and 18 F, which produces detectable g- radiation. The dominant contributor to the 17 O(p,g) 14 N reaction is a resonance at [Special characters omitted.] = 193 keV. The strength of this resonance has been measured and the results are presented. For the 17 O(p,g) 18 F reaction, the dominant contribution comes from the nonresonant direct capture process. The literature direct capture cross sections currently differ by a factor of two. This cross section has been measured in the current work and the results are also presented. New reaction rates have been calculated with these measured cross sections using a new Monte Carlo technique and these new rates have significantly reduced uncertainties compared to the current literature.
Carvalho, Janessa O; Tommet, Doug; Crane, Paul K; Thomas, Michael L; Claxton, Amy; Habeck, Christian; Manly, Jennifer J; Romero, Heather R
2015-07-01
To evaluate the effects of vascular conditions and education quality on cognition over time in White and African American (AA) older adults. We investigated cross-sectional and longitudinal racial differences in executive functioning (EF) and memory composites among Whites (n = 461) and AAs (n = 118) enrolled in a cohort study. We examined whether cerebrovascular risk factors and Shipley Vocabulary scores (a proxy for education quality) accounted for racial differences. On average, AAs had lower quality of education and more cerebrovascular risk factors including hypertension, diabetes, and obesity. AAs had lower mean EF and memory at baseline, but there were no group differences in rates of decline. Cross-sectional racial differences in EF and memory persisted after controlling for vascular disease, but disappeared when controlling for Shipley Vocabulary. Quality of education appears to be more important than cerebrovascular risk factors in explaining cross-sectional differences in memory and EF performance between White and AA older adults. Further investigation is needed regarding the relative contribution of education quality and cerebrovascular risk factors to cognitive decline among ethnically/racially diverse older adults. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
The Ultimate Monte Carlo: Studying Cross-Sections With Cosmic Rays
NASA Technical Reports Server (NTRS)
Wilson, Thomas L.
2007-01-01
The high-energy physics community has been discussing for years the need to bring together the three principal disciplines that study hadron cross-section physics - ground-based accelerators, cosmic-ray experiments in space, and air shower research. Only recently have NASA investigators begun discussing the use of space-borne cosmic-ray payloads to bridge the gap between accelerator physics and air shower work using cosmic-ray measurements. The common tool used in these three realms of high-energy hadron physics is the Monte Carlo (MC). Yet the obvious has not been considered - using a single MC for simulating the entire relativistic energy range (GeV to EeV). The task is daunting due to large uncertainties in accelerator, space, and atmospheric cascade measurements. These include inclusive versus exclusive cross-section measurements, primary composition, interaction dynamics, and possible new physics beyond the standard model. However, the discussion of a common tool or ultimate MC might be the very thing that could begin to unify these independent groups into a common purpose. The Offline ALICE concept of a Virtual MC at CERN s Large Hadron Collider (LHC) will be discussed as a rudimentary beginning of this idea, and as a possible forum for carrying it forward in the future as LHC data emerges.
Sutton, Jeffrey A; Driscoll, James F
2004-11-15
Rayleigh scattering cross sections are measured for nine combustion species (Ar, N2, O2, CO2, CO, H2, H2O, CH4, and C3H8) at wavelengths of 266, 355, and 532 nm and at temperatures ranging from 295 to 1525 K. Experimental results show that, as laser wavelengths become shorter, polarization effects become important and the depolarization ratio of the combustion species must be accounted for in the calculation of the Rayleigh scattering cross section. Temperature effects on the scattering cross section are also measured. Only a small temperature dependence is measured for cross sections at 355 nm, resulting in a 2-8% increase in cross section at temperatures of 1500 K. This temperature dependence increases slightly for measurements at 266 nm, resulting in a 5-11% increase in cross sections at temperatures of 1450 K.
Electron impact cross sections for the 2,2P state excitation of lithium
NASA Technical Reports Server (NTRS)
Vuskovic, L.; Trajmar, S.; Register, D. F.
1982-01-01
Electron impact excitation of the 2p 2P state of Li was studied at 10, 20, 60, 100, 150 and 200 eV. Relative differential cross sections in the angular range 3-120 deg were measured and then normalized to the absolute scale by using the optical f value. Integral and momentum transfer cross sections were obtained by extrapolating the differential cross sections to 0 deg and to 180 deg. The question of normalizing electron-metal-atom collision cross sections in general was examined and the method of normalization to optical f values in particular was investigated in detail. It has been concluded that the extrapolation of the apparent generalized oscillator strength (obtained from the measured differential cross sections) to the zero momentum transfer limit with an expression using even powers of the momentum transfer and normalization of the limit to the optical f value yields reliable absolute cross sections.
The 75As(n,2n) Cross Sections into the 74As Isomer and Ground State
DOE Office of Scientific and Technical Information (OSTI.GOV)
Younes, W; Garrett, P E; Becker, J A
2003-06-30
The {sup 75}As(n, 2n) cross section for the population of the T{sub 1/2} = 26.8-ns isomer at E{sub x} = 259.3 keV in {sup 74}As has been measured as a function of incident neutron energy, from threshold to E{sub n} = 20 MeV. The cross section was measured using the GEANIE spectrometer at LANSCE/WNR. For convenience, the {sup 75}As(n, 2n) population cross section for the {sup 74}As ground state has been deduced as the difference between the previously-known (n, 2n) reaction cross section and the newly measured {sup 75}As(n, 2n){sup 74}As{sup m} cross section. The (n, 2n) reaction, ground-state, andmore » isomer population cross sections are tabulated in this paper.« less
Total and partial photoneutron cross sections for Pb isotopes
NASA Astrophysics Data System (ADS)
Kondo, T.; Utsunomiya, H.; Goriely, S.; Daoutidis, I.; Iwamoto, C.; Akimune, H.; Okamoto, A.; Yamagata, T.; Kamata, M.; Itoh, O.; Toyokawa, H.; Lui, Y.-W.; Harada, H.; Kitatani, F.; Hilaire, S.; Koning, A. J.
2012-07-01
Using quasimonochromatic laser-Compton scattering γ rays, total photoneutron cross sections were measured for 206,207,208Pb near neutron threshold with a high-efficiency 4π neutron detector. Partial E1 and M1 photoneutron cross sections along with total cross sections were determined for 207,208Pb at four energies near threshold by measuring anisotropies in photoneutron emission with linearly polarized γ rays. The E1 strength dominates over the M1 strength in the neutron channel where E1 photoneutron cross sections show extra strength of the pygmy dipole resonance in 207,208Pb near the neutron threshold corresponding 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 an M1 cross section less than 10% of the total photoneutron cross section.
Data Needs for Stellar Atmosphere and Spectrum Modeling
NASA Technical Reports Server (NTRS)
Short, C. I.
2006-01-01
The main data need for stellar atmosphere and spectrum modeling remains atomic and molecular transition data, particularly energy levels and transition cross-sections. We emphasize that data is needed for bound-free (b - f) as well as bound-bound (b - b), and collisional as well as radiative transitions. Data is now needed for polyatomic molecules as well as atoms, ions, and diatomic molecules. In addition, data for the formation of, and extinction due to, liquid and solid phase dust grains is needed. A prioritization of species and data types is presented, and gives emphasis to Fe group elements, and elements important for the investigation of nucleosynthesis and Galactic chemical evolution, such as the -elements and n-capture elements. Special data needs for topical problems in the modeling of cool stars and brown dwarfs are described.
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…
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…
Activation cross section and isomeric cross section ratio for the 76Ge(n,2n)75m,gGe process
NASA Astrophysics Data System (ADS)
Luo, Junhua; Jiang, Li; Wang, Xinxing
2018-04-01
We measured neutron-induced reaction cross sections for the 76Ge(n,2n)75m,gGe reactions and their isomeric cross section ratios σm/σg at three neutron energies between 13 and 15MeV by an activation and off-line γ-ray spectrometric technique using the K-400 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). Ge samples and Nb monitor foils were activated together to determine the reaction cross section and the incident neutron flux. The monoenergetic neutron beams were formed via the 3H( d, n)4He reaction. The pure cross section of the ground state was derived from the absolute cross section of the metastable state and the residual nuclear decay analysis. The cross sections were also calculated using the nuclear model code TALYS-1.8 with different level density options at neutron energies varying from the reaction threshold to 20MeV. Results are discussed and compared with the corresponding literature data.
O2 absorption cross sections /187-225 nm/ from stratospheric solar flux measurements
NASA Technical Reports Server (NTRS)
Herman, J. R.; Mentall, J. E.
1982-01-01
The absorption cross sections of molecular oxygen are calculated in the wavelength range from 187 to 230 nm from solar flux measurements obtained within the stratosphere. Within the Herzberg continuum wavelength region the molecular oxygen cross sections are found to be about 30% smaller than the laboratory results of Shardanand and Rao (1977) from 200 to 210 nm and about 50% smaller than those of Hasson and Nicholls (1971). At wavelengths longer than 210 nm the cross sections agree with those of Shardanand and Rao. The effective absorption cross sections of O2 in the Schumann-Runge band region from 187 to 200 nm are calculated and compared to the empirical fit given by Allen and Frederick (1982). The calculated cross sections indicate that the transmissivity of the atmosphere may be underestimated by the use of the Allen and Frederic cross sections between 195 and 200 nm. The ozone column content between 30 and 40 km and the relative ozone cross sections are determined from the same solar flux data set.
NASA Astrophysics Data System (ADS)
Battistella, C.; Robinson, D.; McQuarrie, N.; Ghoshal, S.
2017-12-01
Multiple valid balanced cross sections can be produced from mapped surface and subsurface data. By integrating low temperature thermochronologic data, we are better able to predict subsurface geometries. Existing valid balanced cross section for far western Nepal are few (Robinson et al., 2006) and do not incorporate thermochronologic data because the data did not exist. The data published along the Simikot cross section along the Karnali River since then include muscovite Ar, zircon U-Th/He and apatite fission track. We present new mapping and a new valid balanced cross section that takes into account the new field data as well as the limitations that thermochronologic data places on the kinematics of the cross section. Additional constrains include some new geomorphology data acquired since 2006 that indicate areas of increased vertical uplift, which indicate locations of buried ramps in the Main Himalayan thrust and guide the locations of Lesser Himalayan ramps in the balanced cross section. Future work will include flexural modeling, new low temperature thermochronometic data, and 2-D thermokinematic models from a sequentially forward modeled balanced cross sections in far western Nepal.
NASA Technical Reports Server (NTRS)
Fahr, A.; Braun, W.; Kurylo, M. J.
1993-01-01
Ultraviolet absorption cross sections of CH3CFCl2(HCFC-141b) were determined in the gas phase (190-260 nm) and liquid phase (230-260 mm) at 298 K. The liquid phase absorption cross sections were then converted into accurate gas phase values using a previously described procedure. It has been demonstrated that scattered light from the shorter-wavelength region (as little as several parts per thousand) can seriously compromise the absorption cross-section measurement, particularly at longer wavelengths where cross sections are low, and can be a source of discrepancies in the cross sections of weakly absorbing halocarbons reported in the literature. A modeling procedure was developed to assess the effect of scattered light on the measured absorption cross section in our experiments, thereby permitting appropriate corrections to be made on the experimental values. Modeled and experimental results were found to be in good agreement. Experimental results from this study were compared with other available determinations and provide accurate input for calculating the atmospheric lifetime of HCFC-141b.
Low-energy proton induced M X-ray production cross sections for 70Yb, 81Tl and 82Pb
NASA Astrophysics Data System (ADS)
Shehla; Mandal, A.; Kumar, Ajay; Roy Chowdhury, M.; Puri, Sanjiv; Tribedi, L. C.
2018-07-01
The cross sections for production of Mk (k = Mξ, Mαβ, Mγ, Mm1) X-rays of 70Yb, 81Tl and 82Pb induced by 50-250 keV protons have been measured in the present work. The experimental cross sections have been compared with the earlier reported values and those calculated using the ionization cross sections based on the ECPSSR (Perturbed (P) stationary(S) state(S), incident ion energy (E) loss, Coulomb (C) deflection and relativistic (R) correction) model, the X-ray emission rates based on the Dirac-Fock model, the fluorescence and Coster-Kronig yields based on the Dirac-Hartree-Slater (DHS) model. In addition, the present measured proton induced X-ray production cross sections have also been compared with those calculated using the Dirac-Hartree-Slater (DHS) model based ionization cross sections and those based on the Plane wave Born Approximation (PWBA). The measured M X-ray production cross sections are, in general, found to be higher than the ECPSSR and DHS model based values and lower than the PWBA model based cross sections.
Positron induced scattering cross sections for hydrocarbons relevant to plasma
NASA Astrophysics Data System (ADS)
Singh, Suvam; Antony, Bobby
2018-05-01
This article explores positron scattering cross sections by simple hydrocarbons such as ethane, ethene, ethyne, propane, and propyne. Chemical erosion processes occurring on the surface due to plasma-wall interactions are an abundant source of hydrocarbon molecules which contaminate the hydrogenic plasma. These hydrocarbons play an important role in the edge plasma region of Tokamak and ITER. In addition to this, they are also one of the major components in the planetary atmospheres and astrophysical mediums. The present work focuses on calculation of different positron impact interactions with simple hydrocarbons in terms of the total cross section (Qtot), elastic cross section (Qel), direct ionization cross section (Qion), positronium formation cross section (Qps), and total ionization cross section (Qtion). Knowing that the positron-plasma study is one of the trending fields, the calculated data have diverse plasma and astrophysical modeling applications. A comprehensive study of Qtot has been provided where the inelastic cross sections have been reported for the first time. Comparisons are made with those available from the literature, and a good agreement is obtained with the measurements.
Rachel White; Randy Molina
2006-01-01
The USDA Forest Service Pacific Northwest Research Station's Biodiversity Initiative seeks to determine the types of science tools needed by natural resource professionals to meet diverse and complex biodiversity goals. During the scoping phase of this Initiative, we asked a broad cross-section of people whose work involves managing for biodiversity, from state...
ERIC Educational Resources Information Center
Frei, Simone; Frei, Balz; Bobe, Gerd
2014-01-01
Are Extension healthy youth programs needed in highly educated U.S. communities? To answer this question, 175 children from four public elementary schools in Corvallis, Oregon, self-reported in a cross-sectional study their dietary intake, and 71 children provided a blood sample for measuring vitamin D concentrations. Most children had…
ERIC Educational Resources Information Center
Kim-Godwin, Yeoun Soo; Clements, Carrie; Bullers, Susan; Maume, Michael; Demski, Elizabeth
2007-01-01
Considering that current trends in sexual behavior and alcohol use among adolescents pose a significant public health risk, more research is needed in this area. Using a cross-sectional design, this study examined sex and alcohol behaviors among middle school and high school students in southeastern North Carolina. The findings suggested that…
ERIC Educational Resources Information Center
Bina, Rena; Yum, Joohee; Hall, Diane M. Harnek; Sowbel, Lynda; Mollette, Angela; Jani, Jayshree; Smith-Osborne, Alexa
2008-01-01
As frontline mental health care providers, social workers need to be prepared to confront and properly manage substance abuse issues in practice. This study examined predictors of recent master of social work (MSW) graduates' perceptions of preparedness to practice in the area of substance abuse. A cross-sectional design was used, and 232 recent…
Raising Health Literacy and Promoting Empowerment to Meet the Challenges of Aging in Hong Kong
ERIC Educational Resources Information Center
Chau, Pui Hing; Mak, Benise; Choy, Shuk Yi; Chan, Kam Che; Cheung, Sai Hei; Woo, Jean
2010-01-01
This study aimed to determine the educational needs of members of the public and related professional disciplines in order to improve health literacy in elderly issues. A cross-sectional survey was conducted in 2007; 2,694 subjects were recruited from the noninstitutional Hong Kong population aged 16 years and over. Undergraduate students of…
ERIC Educational Resources Information Center
Baillie, Lesley; Merritt, Jane; Cox, Janet; Crichton, Nicola
2015-01-01
Older people who are living with dementia often need healthcare, including hospital admissions, due to additional health conditions. Caring for older people who are living with dementia is, therefore, a core nursing role. This study investigated student nurses' expectations of, and confidence about, caring for older people with dementia and the…
DEBRIS: a computer program for analyzing channel cross sections
Patrick Deenihan; Thomas E. Lisle
1988-01-01
DEBRIS is a menu-driven, interactive computer program written in FORTRAN 77 for recording and plotting survey data and for computing hydraulic variables and depths of scour and fill. It was developed for use with the USDA Forest Service's Data General computer system, with the AOS/VS operation system. By using menus, the operator does not need to know any...
ERIC Educational Resources Information Center
Kahveci, Ajda
2009-01-01
The curricula of teacher education need periodic revisions to respond to the evolution of educational objectives. Teachers' beliefs, as well as their characteristics, teaching attitudes and competency in their subject matter play a decisive role in the success of any reform. In this study, a cross-sectional survey was conducted across years 1-5 of…
Post-Mortem and Effective Measure of Science Programs: A Study of Bangladesh Open University
ERIC Educational Resources Information Center
Numan, Sharker Md.; Islam, Md. Anwarul; Shah, A. K. M. Azad
2013-01-01
Distance education can be more learners centered if distance educators are aware of the problems, needs, attitudes and characteristics of their learners. The aim of this study was to compare the learners' profile in terms of their attitude and demography between the learners of computer science and health science. A cross-sectional study design…
ERIC Educational Resources Information Center
Muus, Kyle J.; Knudson, Alana D.; Klug, Marilyn G.; Wynne, Joshua
2011-01-01
Context/Purpose: Most rural hospitals can provide medical care to acute myocardial infarction (AMI) patients, but a need for advanced cardiac care requires timely transfer to a tertiary hospital. There is little information on AMI in-hospital mortality predictors among rural transfer patients. Methods: Cross-sectional retrospective analyses on…
DEBRIS: A computer program for analyzing channel cross sections
Patrick Deenihan; Thomas E. Lisle
1988-01-01
DEBRIS is a menu-driven, interactive computer program written in FORTRAN 77 for recording and platting survey data and for computing hydraulic variables and depths of scour and fill. It was developed for use with the USDA Forest Service's Data General computer system, with the AOS/VS operating system. By using menus, the operator does not need to know any...
Work Stressors and the Quality of Life in Long-Term Care Units
ERIC Educational Resources Information Center
Pekkarinen, Laura; Sinervo, Timo; Perala, Marja-Leena; Elovainio, Marko
2004-01-01
Purpose. The purpose of this work was to examine how structural factors, residents' needs for physical and psychosocial assistance, and the work stressors experienced by employees are related to the quality of life of elderly residents in long-term care. Design and Methods. Cross-sectional survey data were collected from 1,194 employees and 1,079…
Drug use, mental health and problems related to crime and violence: cross-sectional study1
Claro, Heloísa Garcia; de Oliveira, Márcia Aparecida Ferreira; Bourdreaux, Janet Titus; Fernandes, Ivan Filipe de Almeida Lopes; Pinho, Paula Hayasi; Tarifa, Rosana Ribeiro
2015-01-01
Objective: to investigate the correlation between disorders related to the use of alcohol and other drugs and symptoms of mental disorders, problems related to crime and violence and to age and gender. Methods: cross-sectional descriptive study carried out with 128 users of a Psychosocial Care Center for Alcohol and other Drugs, in the city of São Paulo, interviewed by means of the instrument entitled Global Appraisal of Individual Needs - Short Screener. Univariate and multiple linear regression models were used to verify the correlation between the variables. Results: using univariate regression models, internalizing and externalizing symptoms and problems related to crime/violence proved significant and were included in the multiple model, in which only the internalizing symptoms and problems related to crime and violence remained significant. Conclusions: there is a correlation between the severity of problems related to alcohol use and severity of mental health symptoms and crime and violence in the study sample. The results emphasize the need for an interdisciplinary and intersectional character of attention to users of alcohol and other drugs, since they live in a socially vulnerable environment. PMID:26626010
Post-traumatic stress disorder among Syrian refugees in Turkey: a cross-sectional study.
Alpak, Gokay; Unal, Ahmet; Bulbul, Feridun; Sagaltici, Eser; Bez, Yasin; Altindag, Abdurrahman; Dalkilic, Alican; Savas, Haluk A
2015-03-01
Refugees have had major challenges to meet their health care needs throughout history especially in war zones and natural disaster times. The health care needs of Syrian refugees have been becoming an increasingly important issue. We aimed to examine the prevalence of post-traumatic stress disorder (PTSD) and explore its relation with various socioeconomic variables among Syrian refugees, who sought asylum in Turkey. This cross-sectional study was conducted in a tent city. Sample size calculation yielded 352 and the participants of the study were determined randomly. Experienced and native Arabic speaking, psychiatrist evaluated the participants. The frequency of PTSD was 33.5%. Through the binary logistic regression analysis, we calculated that the probability of having PTSD among Syrian refugees in our sample was 71%, if they had the following features: with female gender; being diagnosed with psychiatric disorder in the past; having a family history of psychiatric disorder; and experiencing 2 or more traumas. The findings of our study suggest that PTSD among Syrian refugees in Turkey might be an important mental health issue in refugee camps especially among female refugees, who were exposed to 2 or more traumatic events and had a personal or family history of psychiatric disorder.
Neutron induced fission of 237Np - status, challenges and opportunities
NASA Astrophysics Data System (ADS)
Ruskov, Ivan; Goverdovski, Andrei; Furman, Walter; Kopatch, Yury; Shcherbakov, Oleg; Hambsch, Franz-Josef; Oberstedt, Stephan; Oberstedt, Andreas
2018-03-01
Nowadays, there is an increased interest in a complete study of the neutron-induced fission of 237Np. This is due to the need of accurate and reliable nuclear data for nuclear science and technology. 237Np is generated (and accumulated) in the nuclear reactor core during reactor operation. As one of the most abundant long-lived isotopes in spent fuel ("waste"), the incineration of 237Np becomes an important issue. One scenario for burning of 237Np and other radio-toxic minor actinides suggests they are to be mixed into the fuel of future fast-neutron reactors, employing the so-called transmutation and partitioning technology. For testing present fission models, which are at the basis of new generation nuclear reactor developments, highly accurate and detailed neutron-induced nuclear reaction data is needed. However, the EXFOR nuclear database for 237Np on neutron-induced capture cross-section, σγ, and fission cross-section, σf, as well as on the characteristics of capture and fission resonance parameters (Γγ, Γf, σoΓf, fragments mass-energy yield distributions, multiplicities of neutrons vn and γ-rays vγ), has not been updated for decades.
Low energy electron-molecule scattering using the R-matrix method
NASA Astrophysics Data System (ADS)
Gorfinkiel, Jimena
2014-10-01
The study of electron-molecule collisions continues to attract significant interest stimulated, in no small part, by the need for collisional data to model a number of physical environments and applied processes (e.g. the modelling of focused electron beam induced deposition and the description of the interaction of radiation with biological matter). This need for electron scattering data (cross sections but also information on the temporary negative ions, TNI, that can be formed) has motivated the renewed development of theoretical methodology and their computational implementation. I will present the latest developments in the study of low energy electron scattering from molecules and molecular clusters using the R-matrix method. Recent calculations on electron collisions with biologically relevant molecules have shed light on the formation of core-excited TNI these larger targets. The picture that emerges is much more complex than previously thought. I will discuss some examples as well as current and future developments of the methodology and software in order to provide more accurate collisional data (in particular cross sections) for bigger targets. In collaboration with Zdenek Masin, The Open University. This work was partially supported by EPSRC.
Unanue, Wenceslao; Gómez, Marcos E.; Cortez, Diego; Oyanedel, Juan C.; Mendiburo-Seguel, Andrés
2017-01-01
The link between job satisfaction and life satisfaction has been extensively explored in the relevant literature. However, the great majority of past research has been carried out using cross-sectional analyses, and almost exclusively in the Western world. Moreover, the underlying psychological mechanisms explaining the link are not yet completely understood. Thus, we report the first research to date which uses both cross-sectional and longitudinal data among workers in Chile—a fast-developing Latin American economy—and which aims to tackle previous limitations. Three studies consistently support a positive link between the constructs. Study 1 (N = 636) found that higher job satisfaction predicted higher life satisfaction both contemporaneously and longitudinally, and vice versa, above and beyond several key control variables. Study 2 (N = 725) and Study 3 (N = 703) replicated Study 1 results, but tested for the first time the role of satisfaction of basic psychological needs (as stated by self-determination theory) in the job–life satisfaction link. This is the most novel contribution of our paper. Key implications not only for individual quality of life, but also for companies' human resource practices emerge from our findings. PMID:28536541
Gupta, Ritu; Acharya, Arun Kumar
2016-01-01
Background and Objectives. Pregnancy can be a risk factor for dental diseases as oral tissues are liable to changes due to hormonal variations. The aim of the study was to assess the oral health status and treatment needs among pregnant women of Raichur district, Karnataka, India. Methods. Cross-sectional data was collected from 300 primigravidae from all the 5 taluks of Raichur district visiting the respective community health centre at taluk headquarters. A specially designed questionnaire was used to assess the demographic variables and oral hygiene practices. A clinical examination was done according to WHO (World Health Organization) criteria 1997 and recorded using WHO Oral Health Assessment Form. Results. The mean age of the pregnant women in the study was 21.8 (2.12) years. The prevalence of caries and periodontal diseases was 62.7% and 95%, respectively. The mean DT, MT, FT, and DMFT were 2.06 (2.5), 0.03 (0.17), 0.04 (0.27), and 2.13 (2.54), respectively. The mean OHI-S was 2.87 (1.27). Chi-square test showed that CPI scores increased with the trimester of pregnancy. Conclusion. The present study demonstrates poor oral hygiene and high prevalence of periodontal diseases, as well as a large proportion of unmet dental treatment needs among pregnant women of Raichur district, India.
A Cross-Sectional Study of the Psychological Needs of Adults Living with Cystic Fibrosis
Pakhale, Smita; Baron, Justine; Armstrong, Michael; Tasca, Georgio; Gaudet, Ena; Aaron, Shawn; Cameron, William; Balfour, Louise
2015-01-01
Background Depression and anxiety are prevalent in people with cystic fibrosis (CF), yet psychological services are rarely accessible in CF clinics. This cross-sectional single center study reports on a psychological needs assessment of people with CF. Methods We asked adults attending a CF clinic, without integrated psychological services, to complete a psychological needs assessment survey that included items on: a) past access to psychological services (via a CF referral service), b) concerns relevant to discuss with a psychologist, and c) their likelihood of accessing psychological services if available at the CF clinic, and standardized measures of depression (CES-D) and anxiety (GAD-7). Results We enrolled 49 participants and 45 (91.8%) completed the survey. Forty percent reported elevated symptoms of depression and 13% had elevated anxiety. A majority of individuals (72.2% and 83.3%, respectively) indicated they would be likely to use psychological services, if available at the clinic. Concerns considered most relevant to discuss with a psychologist were: 1) worries (51.1%), 2) mood (44.4%), 3) life stress (46.6%), 4) adjustment to CF (42.2%), 5) life transitions (42.2%) and 6) quality of life (42.2%). Conclusions This study highlights the rationale for screening adults with CF for depression and anxiety, and to facilitate provision of psychological services and preventative mental health interventions as an integral component of multi-disciplinary CF care. PMID:26102351
Acharya, Arun Kumar
2016-01-01
Background and Objectives. Pregnancy can be a risk factor for dental diseases as oral tissues are liable to changes due to hormonal variations. The aim of the study was to assess the oral health status and treatment needs among pregnant women of Raichur district, Karnataka, India. Methods. Cross-sectional data was collected from 300 primigravidae from all the 5 taluks of Raichur district visiting the respective community health centre at taluk headquarters. A specially designed questionnaire was used to assess the demographic variables and oral hygiene practices. A clinical examination was done according to WHO (World Health Organization) criteria 1997 and recorded using WHO Oral Health Assessment Form. Results. The mean age of the pregnant women in the study was 21.8 (2.12) years. The prevalence of caries and periodontal diseases was 62.7% and 95%, respectively. The mean DT, MT, FT, and DMFT were 2.06 (2.5), 0.03 (0.17), 0.04 (0.27), and 2.13 (2.54), respectively. The mean OHI-S was 2.87 (1.27). Chi-square test showed that CPI scores increased with the trimester of pregnancy. Conclusion. The present study demonstrates poor oral hygiene and high prevalence of periodontal diseases, as well as a large proportion of unmet dental treatment needs among pregnant women of Raichur district, India. PMID:27293984
Technical Data to Justify Full Burnup Credit in Criticality Safety Licensing Analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Enercon Services, Inc.
2011-03-14
Enercon Services, Inc. (ENERCON) was requested under Task Order No.2 to identify scientific and technical data needed to benchmark and justify Full Burnup Credit, which adds 16 fission products and 4 minor actinides1 to Actinide-Only burnup credit. The historical perspective for Full Burnup Credit is discussed, and interviews of organizations participating in burnup credit activities are summarized as a basis for identifying additional data needs and making recommendation. Input from burnup credit participants representing two segments of the commercial nuclear industry is provided. First, the Electric Power Research Institute (EPRI) has been very active in the development of Full Burnupmore » Credit, representing the interests of nuclear utilities in achieving capacity gains for storage and transport casks. EPRI and its utility customers are interested in a swift resolution of the validation issues that are delaying the implementation of Full Burnup Credit [EPRI 2010b]. Second, used nuclear fuel storage and transportation Cask Vendors favor improving burnup credit beyond Actinide-Only burnup credit, although their discussion of specific burnup credit achievements and data needs was limited citing business sensitive and technical proprietary concerns. While Cask Vendor proprietary items are not specifically identified in this report, the needs of all nuclear industry participants are reflected in the conclusions and recommendations of this report. In addition, Oak Ridge National Laboratory (ORNL) and Sandia National Laboratory (SNL) were interviewed for their input into additional data needs to achieve Full Burnup Credit. ORNL was very open to discussions of Full Burnup Credit, with several telecoms and a visit by ENERCON to ORNL. For many years, ORNL has provided extensive support to the NRC regarding burnup credit in all of its forms. Discussions with ORNL focused on potential resolutions to the validation issues for the use of fission products. SNL was helpful in ENERCON's understanding of the difficult issues related to obtaining and analyzing additional cross section test data to support Full Burnup Credit. A PIRT (Phenomena Identification and Ranking Table) analysis was performed by ENERCON to evaluate the costs and benefits of acquiring different types of nuclear data in support of Full Burnup Credit. A PIRT exercise is a formal expert elicitation process with the final output being the ranking tables. The PIRT analysis (Table 7-4: Results of PIRT Evaluation) showed that the acquisition of additional Actinide-Only experimental data, although beneficial, was associated with high cost and is not necessarily needed. The conclusion was that the existing Radiochemical Assay (RCA) data plus the French Haut Taux de Combustion (HTC)2 and handbook Laboratory Critical Experiment (LCE) data provide adequate benchmark validation for Actinide-Only Burnup Credit. The PIRT analysis indicated that the costs and schedule to obtain sufficient additional experimental data to support the addition of 16 fission products to Actinide-Only Burnup Credit to produce Full Burnup Credit are quite substantial. ENERCON estimates the cost to be $50M to $100M with a schedule of five or more years. The PIRT analysis highlights another option for fission product burnup credit, which is the application of computer-based uncertainty analyses (S/U - Sensitivity/Uncertainty methodologies), confirmed by the limited experimental data that is already available. S/U analyses essentially transform cross section uncertainty information contained in the cross section libraries into a reactivity bias and uncertainty. Recent work by ORNL and EPRI has shown that a methodology to support Full Burnup Credit is possible using a combination of traditional RCA and LCE validation plus S/U validation for fission product isotopics and cross sections. Further, the most recent cross section data (ENDF/B-VII) can be incorporated into the burnup credit codes at a reasonable cost compared to the acquisition of equivalent experimental data. ENERCON concludes that even with the costs of code data library updating, the use of S/U analysis methodologies could be accomplished on a shorter schedule and a lower cost than the gathering of sufficient experimental data. ENERCON estimates of the costs of an updated S/U computer code and data suite are $5M to $10M with a schedule of two to three years. Recent ORNL analyses using the S/U analysis method show that the bias and uncertainty values for fission product cross sections are smaller than previously expected. This result is confirmed by a similar EPRI approach using different data and computer codes. ENERCON also found that some issues regarding the implementation of burnup credit appear to have been successfully resolved especially the axial burnup profile issue and the depletion parameter issue. These issues were resolved through data gathering activities at the Yucca Mountain Project and ORNL.« less
Electron induced inelastic and ionization cross section for plasma modeling
NASA Astrophysics Data System (ADS)
Verma, Pankaj; Mahato, Dibyendu; Kaur, Jaspreet; Antony, Bobby
2016-09-01
The present paper reports electron impact total inelastic and ionization cross section for silicon, germanium, and tin tetrahalides at energies varying from ionization threshold of the target to 5000 eV. These cross section data over a wide energy domain are very essential to understand the physico-chemical processes involved in various environments such as plasma modeling, semiconductor etching, atmospheric sciences, biological sciences, and radiation physics. However, the cross section data on the above mentioned molecules are scarce. In the present article, we report the computation of total inelastic cross section using spherical complex optical potential formalism and the estimation of ionization cross section through a semi-empirical method. The present ionization cross section result obtained for SiCl4 shows excellent agreement with previous measurements, while other molecules have not yet been investigated experimentally. Present results show more consistent behaviour than previous theoretical estimates. Besides cross sections, we have also studied the correlation of maximum ionization cross section with the square root of the ratio of polarizability to ionization potential for the molecules with known polarizabilities. A linear relation is observed between these quantities. This correlation is used to obtain approximate polarizability volumes for SiBr4, SiI4, GeCl4, GeBr4, and GeI4 molecules.
Breakup and fusion cross sections of the 6Li nucleus with targets of mass A = 58, 144 and 208
NASA Astrophysics Data System (ADS)
Mukeru, B.; Rampho, G. J.; Lekala, M. L.
2018-04-01
We use the continuum discretized coupled channels method to investigate the effects of continuum-continuum coupling on the breakup and fusion cross sections of the weakly bound 6Li nucleus with the 58Ni, 144Sm and 208Pb nuclear targets. The cross sections were analyzed at incident energies E cm below, close to and above the Coulomb barrier V B. We found that for the medium and heavy targets, the breakup cross sections are enhanced at energies below the Coulomb barrier (E cm/V B ≤ 0.8) owing to these couplings. For the lighter target, relatively small enhancement of the breakup cross sections appear at energies well below the barrier (E cm/V B ≤ 0.6). At energies E cm/V B > 0.8 for medium and heavy targets, and E cm/V B > 0.6 for the light target, the continuum-continuum couplings substantially suppress the breakup cross sections. On the other hand, the fusion cross sections are enhanced at energies E cm/V B < 1.4, E cm/V B < 1.2 and E cm/V B < 0.8 for the light, medium and heavy target, respectively. The enhancement decreases as the target mass increases. Above the indicated respective energies, these couplings suppress the fusion cross sections. We also compared the breakup and fusion cross sections, and found that below the barrier, the breakup cross sections are more dominant regardless of whether continuum-continuum couplings are included.
Model selection for pion photoproduction
Landay, J.; Doring, M.; Fernandez-Ramirez, C.; ...
2017-01-12
Partial-wave analysis of meson and photon-induced reactions is needed to enable the comparison of many theoretical approaches to data. In both energy-dependent and independent parametrizations of partial waves, the selection of the model amplitude is crucial. Principles of the S matrix are implemented to a different degree in different approaches; but a many times overlooked aspect concerns the selection of undetermined coefficients and functional forms for fitting, leading to a minimal yet sufficient parametrization. We present an analysis of low-energy neutral pion photoproduction using the least absolute shrinkage and selection operator (LASSO) in combination with criteria from information theory andmore » K-fold cross validation. These methods are not yet widely known in the analysis of excited hadrons but will become relevant in the era of precision spectroscopy. As a result, the principle is first illustrated with synthetic data; then, its feasibility for real data is demonstrated by analyzing the latest available measurements of differential cross sections (dσ/dΩ), photon-beam asymmetries (Σ), and target asymmetry differential cross sections (dσ T/d≡Tdσ/dΩ) in the low-energy regime.« less
Assessing the HIV prevention capacity building needs of community-based organizations.
Richter, D L; Prince, M S; Potts, L H; Reininger, B M; Thompson, M V; Fraser, J P; Fulmer, S L
2000-07-01
Community-based organizations (CBOs) have been providing HIV prevention services to priority populations for many years. Recent research suggests that CBOs could benefit from capacity building to strengthen their public health prevention knowledge and skills, including ability to access and use behavioral science to guide prevention efforts. A cross-sectional survey of 316 CBOs was conducted to assess desire and preferences for training, support for training at the organizational level, motivation for training at the individual level, barriers to training, and factors associated with the perceived need for training. Results suggest the need for a national training initiative to increase CBO capacity.
McDougal, Robert R.; Waltermire, Robert G.; Aldridge, Cameron L.; Germaine, Stephen S.; Nielsen, Scott E.; Nielsen, Charlene C.; Hanson, Leanne; Bowen, Zachary H.
2008-01-01
Based on these results, there are identifiable management considerations. Toilet and rest sites need to be carefully located relative to where sensitive vegetation or soils occur. The analyses presented here indicate that limiting motorized vehicle use needs to be a priority over that of adjusting the number of trekkers. Additionally, monitoring of the Trail from Sixth Crossing to Rock Creek Hollow segment needs to consider explicit management targets, such as minimum acceptable levels of bare ground or trail width, and the establishment of permanent monitoring plots to evaluate targets and measure responses to altered management activities.
Parental Concerns about the Health of Adolescents with Intellectual Disability: A Brief Report
Tucker, Madonna; Taylor Gomez, Miriam; Rey-Conde, Therese; Lennox, Nicholas
2011-01-01
Background. Parents of adolescents with intellectual disability are concerned about the future health and well-being needs of their children. Method. Qualitative data was collected as part of a cross-sectional descriptive study and semi-structured interviews were conducted with 32 parents. The results were themed. Results. Most parents discussed areas of their children's health which made them anxious about the future. These concerns were collated into five themes. Conclusion. The health and well-being themes were dependency, general health, challenging behaviours, and increasing support needs. PMID:22295180
Experimental and Theoretical Understanding of Neutron Capture on Uranium Isotopes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ullmann, John Leonard
2017-09-21
Neutron capture cross sections on uranium isotopes are important quantities needed to model nuclear explosion performance, nuclear reactor design, nuclear test diagnostics, and nuclear forensics. It has been difficult to calculate capture accurately, and factors of 2 or more be- tween calculation and measurements are not uncommon, although normalization to measurements of the average capture width and nuclear level density can improve the result. The calculations of capture for 233,235,237,239U are further complicated by the need to accurately include the fission channel.
NASA Astrophysics Data System (ADS)
Olree, E.; Robinson, D. M.; McQuarrie, N.; Ghoshal, S.; Olsen, J.
2016-12-01
Using balanced cross sections, one can visualize a valid and admissible interpretation of the surface and subsurface data. Khanal (2014) and Cross (2014) produced two valid and admissible cross sections along the Marsyandi River in central Nepal. However, thermochronologic data adds another dimension that must be adhered to when producing valid and admissible balanced cross sections. Since the previous cross sections were produced, additional zircon-helium (ZHe) cooling ages along the Marsyandi River show ages of 1 Ma near the Main Central thrust in the hinterland to 4 Ma near the Main Boundary thrust closer to the foreland. This distribution of cooling ages requires recent uplift in the hinterland, which is not present in the cross sections. Although a restored version of the Khanal (2014) cross section is sequentially deformed using 2D Move, the kinematic sequence implied in the cross section is inconsistent with the ZHe age distribution. The hinterland dipping duplex proposed by Khanal would require cooling ages that are oldest near the Main Central thrust and young southwards toward the active ramp located 80 km north of the Main Frontal thrust. Instead, the 4 Ma age near the Main Boundary thrust and the increasingly younger ages to the north could be produced by either a foreland-dipping Lesser Himalayan duplex, which would keep active uplift in the north, or by translation of the hinterland dipping duplex southward over the ramp, moving the active thrust ramp northward. To address this problem, a new balanced cross section was produced using both new mapping through the region and the ZHe age distribution as additional constraints. The section was then restored and sequentially deformed in 2D Move. This study illustrates that multiple cross sections can be viable and admissible; however, they can still be incorrect. Thermochronology places additional constraints on the permissible geometries, and thus increases our ability to predict subsurface geometries. The next step of this project is to link the uplift and erosion implied by the kinematic sequence of the new cross section to the measured cooling history by importing the cross section kinematics into advection diffusion modeling software that predicts cooling ages.
2013-01-01
Background There is an increased risk of obesity amongst socioeconomically disadvantaged populations and emerging evidence suggests that psychological stress may be a key factor in this relationship. This paper reports the results of cross-sectional and longitudinal analyses of relationships between perceived stress, weight and weight-related behaviours in a cohort of socioeconomically disadvantaged women. Methods This study used baseline and follow-up self-report survey data from the Resilience for Eating and Activity Despite Inequality study, comprising a cohort of 1382 women aged 18 to 46 years from 80 of the most socioeconomically disadvantaged neighbourhoods in Victoria, Australia. Women reported their height (baseline only), weight, sociodemographic characteristics, perceived stress, leisure-time physical activity, sedentary and dietary behaviours at baseline and three-year follow-up. Linear and multinomial logistic regression were used to examine cross-sectional and longitudinal associations between stress (predictor) and weight, and weight-related behaviours. Results Higher perceived stress in women was associated with a higher BMI, and to increased odds of being obese in cross-sectional and longitudinal analyses. Cross-sectional and longitudinal associations were found between stress and both less leisure-time physical activity, and more frequent fast food consumption. Longitudinal associations were also found between stress and increased television viewing time. Conclusion The present study contributes to the literature related to the effects of stress on weight and weight-related behaviours. The findings suggest that higher stress levels could contribute to obesity risk in women. Further research is needed to fully understand the mechanisms underlying these associations. However, interventions that incorporate stress management techniques might help to prevent rising obesity rates among socioeconomically disadvantaged women. PMID:24020677
Track structure simulations at relativistic energies: an update on cross section calculations
NASA Astrophysics Data System (ADS)
Dingfelder, Michael
Charged particle track structure simulations follow the primary, as well as all (produced) sec-ondary particles in an event-by-event matter, from starting or ejection energies down to total stopping. They provide detailed information on the spacial distributions of energy depositions, interaction types, and radical species produced. These quantities provide a starting point to describe the interaction of the radiation with matter of biological interest and to explore and estimate the effects of radiation quality on various biological responses of these systems. Of special interest is liquid water which serves as surrogate for soft tissue. Ionization and excitation cross sections for bare charged particles can be calculated within the framework of the (relativistic) plane-wave Born approximation or the (relativistic) Bethe approximation. Both theories rely on a realistic model of the dielectric response function of the material under consideration and need to address relativistic medium polarization effects like the Fermi-density effect in a consistent way. In this talk we will review and present new and updated aspects of charged particle cross section calculations for relativistic heavy ions with liquid water and other materials of biological interest. This includes an updated model for the dielectric response function of liquid water to better reflect new data from inelastic X-ray scattering (IXS) experiments using synchrotron radiation and a model for the dielectric response function of calcium, which serves as a bone surrogate. We will also discuss the implementation of relativistic effect, especially of the Fermi-density effect into the cross section calculations. This work is supported by the National Aeronautics and Space Administration (NASA), grant no. NNJ04HF39G.
Li, Junxin; Cacchione, Pamela Z; Hodgson, Nancy; Riegel, Barbara; Keenan, Brendan T; Scharf, Mathew T; Richards, Kathy C; Gooneratne, Nalaka S
2017-02-01
To examine the cross-sectional associations between self-reported postlunch napping and structured cognitive assessments in Chinese older adults. Cross-sectional cohort study. China. Individuals aged 65 and older from the baseline national wave of the China Health and Retirement Longitudinal Study (CHARLS) (N = 2,974). Interview-based cognitive assessments of orientation and attention, episodic memory, visuospatial abilities, and a combined global cognition score incorporating these assessments. Other self-reported or interview-based assessments included postlunch napping duration, nighttime sleep duration, demographic characteristics, health habits, comorbidities, functional status and social activities. According to reported napping duration, older adults were categorized as non-nappers (0 minutes), short nappers (<30 minutes), moderate nappers (30-90 minutes), and extended nappers (>90 minutes). Postlunch napping was reporting in 57.7% of participants for a mean of 63 minutes. Cognitive function was significantly associated with napping (P < .001). Between-group comparisons showed that moderate nappers had better overall cognition than nonnappers (P < .001) or extended nappers (P = .01). Nonnappers also had significantly poorer cognition than short nappers (P = .03). In multiple regression analysis, moderate napping was significantly associated with better cognition than non- (P = .004), short (P = .04), and extended napping (P = .002), after controlling for demographic characteristics, body mass index, depression, instrumental activities of daily living, social activities, and nighttime sleep duration. A cross-sectional association was found between moderate postlunch napping and better cognition in Chinese older adults. The cross-sectional design and self-reported measures of sleep limited the findings. Longitudinal studies with objective napping measures are needed to further test this hypothesis. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.
Lugaro, M.; Tagliente, Giuseppe; Karakas, Amanda I.; ...
2013-12-13
We present model predictions for the Zr isotopic ratios produced by slow neutron captures in C-rich asymptotic giant branch (AGB) stars of masses 1.25-4 M-circle dot and metallicities Z = 0.01-0.03, and compare them to data from single meteoritic stardust silicon carbide (SiC) and high-density graphite grains that condensed in the outflows of these stars. We compare predictions produced using the Zr neutron-capture cross sections from Bao et al. and from n_TOF experiments at CERN, and present a new evaluation for the neutron-capture cross section of the unstable isotope Zr-95, the branching point leading to the production of Zr-96. Themore » new cross sections generally present an improved match with the observational data, except for the Zr-92/Zr-94 ratios, which are on average still substantially higher than predicted. The Zr-96/Zr-94 ratios can be explained using our range of initial stellar masses, with the most Zr-96-depleted grains originating from AGB stars of masses 1.8-3 M-circle dot and the others from either lower or higher masses. The Zr-90,Zr-91/Zr-94 variations measured in the grains are well reproduced by the range of stellar metallicities considered here, which is the same needed to cover the Si composition of the grains produced by the chemical evolution of the Galaxy. The Zr-92/Zr-94 versus Si-29/Si-28 positive correlation observed in the available data suggests that stellar metallicity rather than rotation plays the major role in covering the Zr-90,Zr-91,Zr-92/Zr-94 spread« less
Circulating linoleic acid and alpha-linolenic acid and glucose metabolism: the Hoorn Study.
Cabout, Mieke; Alssema, Marjan; Nijpels, Giel; Stehouwer, Coen D A; Zock, Peter L; Brouwer, Ingeborg A; Elshorbagy, Amany K; Refsum, Helga; Dekker, Jacqueline M
2017-09-01
Data on the relation between linoleic acid (LA) and alpha-linolenic acid (ALA) and type 2 diabetes mellitus (T2DM) risk are scarce and inconsistent. The aim of this study was to investigate the association of serum LA and ALA with fasting and 2 h post-load plasma glucose and glycated hemoglobin (HbA1c). This study included 667 participants from third examination (2000) of the population-based Hoorn study in which individuals with glucose intolerance were overrepresented. Fatty acid profiles in serum total lipids were measured at baseline, in 2000. Diabetes risk markers were measured at baseline and follow-up in 2008. Linear regression models were used in cross-sectional and prospective analyses. In cross-sectional analyses (n = 667), serum LA was inversely associated with plasma glucose, both in fasting conditions (B = -0.024 [-0.045, -0.002]) and 2 h after glucose tolerance test (B = -0.099 [-0.158, -0.039]), but not with HbA1c (B = 0.000 [-0.014, 0.013]), after adjustment for relevant factors. In prospective analyses (n = 257), serum LA was not associated with fasting (B = 0.003 [-0.019, 0.025]) or post-load glucose (B = -0.026 [-0.100, 0.049]). Furthermore, no significant associations were found between serum ALA and glucose metabolism in cross-sectional or prospective analyses. In this study, serum LA was inversely associated with fasting and post-load glucose in cross-sectional, but not in prospective analyses. Further studies are needed to elucidate the exact role of serum LA and ALA levels and dietary polyunsaturated fatty acids in glucose metabolism.
Ruhdorfer, AS; Dannhauer, T; Wirth, W; Cotofana, S; Roemer, F; Nevitt, M; Eckstein, F
2014-01-01
Objective To compare cross-sectional and longitudinal side-differences in thigh muscle anatomical cross-sectional areas (ACSAs), muscle strength, and specific strength (strength/ACSA), between knees with early radiographic change vs. knees without radiographic knee osteoarthritis (RKOA), in the same person. Design 55 (of 4796) Osteoarthritis Initiative participants fulfilled the inclusion criteria of early RKOA in one limb (definite tibiofemoral osteophytes; no radiographic joint space narrowing [JSN]) vs. no RKOA (no osteophyte; no JSN) in the contralateral limb. ACSAs of the thigh muscles and quadriceps heads were determined using axial MRIs at 33%/30% femoral length (distal to proximal). Isometric extensor and flexor muscle strength were measured (Good Strength Chair). Baseline quadriceps ACSA and extensor (specific) strength represented the primary analytic focus, and two-year changes of quadriceps ACSAs the secondary focus. Results No statistically significant side-differences in quadriceps (or other thigh muscle) ACSAs, muscle strength, or specific strength were observed between early RKOA vs. contralateral limbs without RKOA (p≥0.44), neither in men nor in women. The two-year reduction in quadriceps ACSA in limbs with early RKOA was −0.9±6% (mean ± standard deviation) vs. −0.5±6% in limbs without RKOA (statistical difference p=0.85). Conclusion Our results do not provide evidence that early unilateral radiographic changes, i.e. presence of osteophytes, are associated with cross-sectional or longitudinal differences in quadriceps muscle status compared with contralateral knees without RKOA. At the stage of early unilateral RKOA there thus appears to be no clinical need for countervailing a potential dys-balance in quadriceps ACSAs and strength between both knees. PMID:25278072
Flow Duct Data for Validation of Acoustic Liner Codes for Impedance Eduction
NASA Technical Reports Server (NTRS)
Ahuja, K. K.; Munro, Scott; Gaeta, R. J., Jr.
2000-01-01
The objective of the study reported here was to acquire acoustic and flow data with hard and lined duct wall duct sections for validation of a liner prediction code being developed at NASA LaRC. Both the mean flowfield and acoustic flowfields were determined in a cross-plane of the rectangular duct. A flow duct facility with acoustic drivers connected to a rectangular (4.7 x 2.0 inch) source section and a linear acoustic liner mounted downstream of the source section was used in this study. The liner section was designed to allow liner materials to be placed on all 4 walls of the duct. The test liner was of the locally-reacting type and was made from a ceramic material. The material, consisting of a tubular structure, was provided by NASA LaRC. The liner was approximately 8.89 cm (3.5 inches) thick. For the current study, only the two "short" sides of the duct were lined with liner material. The other two sides were hard walls. Two especially built instrumentation sections were attached on either sides of the liner section to allow acoustic and flow measurements to be made upstream and downstream of the liner. The two instrumentation duct sections were built to allow measurement of acoustic and flow properties at planes perpendicular to flow upstream and downstream of the liner section. The instrumentation section was also designed to provide a streamwise gradient in acoustic (complex) pressure from which the acoustic particle velocity, needed for the model validation, can be computed. Flow measurements included pressure, temperature, and velocity profiles upstream of the liner section. The in-flow sound pressure levels and phases were obtained with a microphone probe equipped with a nose cone in two cross planes upstream of the liner and two cross plane downstream of the liner. In addition to the acoustic measurements at the cross planes. axial centerline acoustic data was acquired using an axially traversing microphone probe which was traversed from a location upstream of the liner to some distance downstream of the liner. All probes used here had to be calibrated with respect to a standard microphone equipped with a nose cone to allow for the effects of flow.
CESAR5.3: Isotopic depletion for Research and Testing Reactor decommissioning
NASA Astrophysics Data System (ADS)
Ritter, Guillaume; Eschbach, Romain; Girieud, Richard; Soulard, Maxime
2018-05-01
CESAR stands in French for "simplified depletion applied to reprocessing". The current version is now number 5.3 as it started 30 years ago from a long lasting cooperation with ORANO, co-owner of the code with CEA. This computer code can characterize several types of nuclear fuel assemblies, from the most regular PWR power plants to the most unexpected gas cooled and graphite moderated old timer research facility. Each type of fuel can also include numerous ranges of compositions like UOX, MOX, LEU or HEU. Such versatility comes from a broad catalog of cross section libraries, each corresponding to a specific reactor and fuel matrix design. CESAR goes beyond fuel characterization and can also provide an evaluation of structural materials activation. The cross-sections libraries are generated using the most refined assembly or core level transport code calculation schemes (CEA APOLLO2 or ERANOS), based on the European JEFF3.1.1 nuclear data base. Each new CESAR self shielded cross section library benefits all most recent CEA recommendations as for deterministic physics options. Resulting cross sections are organized as a function of burn up and initial fuel enrichment which allows to condensate this costly process into a series of Legendre polynomials. The final outcome is a fast, accurate and compact CESAR cross section library. Each library is fully validated, against a stochastic transport code (CEA TRIPOLI 4) if needed and against a reference depletion code (CEA DARWIN). Using CESAR does not require any of the neutron physics expertise implemented into cross section libraries generation. It is based on top quality nuclear data (JEFF3.1.1 for ˜400 isotopes) and includes up to date Bateman equation solving algorithms. However, defining a CESAR computation case can be very straightforward. Most results are only 3 steps away from any beginner's ambition: Initial composition, in core depletion and pool decay scenario. On top of a simple utilization architecture, CESAR includes a portable Graphical User Interface which can be broadly deployed in R&D or industrial facilities. Aging facilities currently face decommissioning and dismantling issues. This way to the end of the nuclear fuel cycle requires a careful assessment of source terms in the fuel, core structures and all parts of a facility that must be disposed of with "industrial nuclear" constraints. In that perspective, several CESAR cross section libraries were constructed for early CEA Research and Testing Reactors (RTR's). The aim of this paper is to describe how CESAR operates and how it can be used to help these facilities care for waste disposal, nuclear materials transport or basic safety cases. The test case will be based on the PHEBUS Facility located at CEA - Cadarache.
Fragmentation of Ar-40 at 100 GeV/c
NASA Technical Reports Server (NTRS)
Lindstrom, P. J.; Greiner, D. E.; Heckman, H. H.; Cork, B.; Bieser, F. S.
1975-01-01
The delta Z is greater than or equal to 1 reaction cross section for 1.8 GeV/n Ar-40 have been measured on targets ranging from H to Pb. Comparing these cross sections with H-1, C-12, and O-16 reaction cross sections at relativistic energies yields a formula for nucleus-nucleus reaction cross sections.
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.
NASA Technical Reports Server (NTRS)
Yoshino, K.; Esmond, J. R.; Freeman, D. E.; Parkinson, W. H.
1993-01-01
Laboratory measurements of the relative absorption cross sections of ozone at temperatures 195, 228, and 295 K have been made throughout the 185 to 254 nm wavelength region. The absolute absorption cross sections at the same temperatures have been measured at several discrete wavelengths in the 185 to 250 nm region. The absolute cross sections of ozone have been used to put the relative cross sections on a firm absolute basis throughout the 185 to 255 nm region. These recalibrated cross sections are slightly lower than those of Molina and Molina (1986), but the differences are within a few percent and would not be significant in atmospheric applications.
Fragmentation cross sections of O-16 between 0.9 and 200 GeV/nucleon
NASA Technical Reports Server (NTRS)
Hirzebruch, S. E.; Heinrich, W.; Tolstov, K. D.; Kovalenko, A. D.; Benton, E. V.
1995-01-01
Inclusive cross sections for high energy interactions at 0.9, 2.3, 3.6, and 13.5 GeV/nucleon of O-16 with C, CR-39 (C12H18O7), CH2, Al, Cu, Ag, and Pb targets were measured. The total charge-changing cross sections and partial charge-changing cross sections for the production of fragments with charge Z = 6 and Z = 7 are compared to previous experiments at 60 and 200 GeV/nucleon. The contributions of Coulomb dissociation to the total cross sections are calculated. Using factorization rules the partial electromagnetic cross sections are separated from the nuclear components. Energy dependence of both components are investigated and discussed.
Nuclear annihilation by antinucleons
Lee, Teck-Ghee; Wong, Cheuk-Yin
2016-01-25
We examine the momentum dependence ofmore » $$\\bar{p}$$p and $$\\bar{n}$$p annihilation cross sections by considering the transmission through a nuclear potential and the $$\\bar {p}$$p Coulomb interaction. Compared to the $$\\bar{n}$$p annihilation cross section, the $$\\bar{p}$$p annihilation cross section is significantly enhanced by the Coulomb interaction for projectile momenta below p lab < 500 MeV/c, and the two annihilation cross sections approach the Pomeranchuk's equality limit [JETP 30, 423 (1956)] at p lab ~500 MeV/c. Using these elementary cross sections as the basic input data, the extended Glauber model is employed to evaluate the annihilation cross sections for $$\\bar{n}$$ and $$\\bar{p}$$ interaction with nuclei and the results compare well with experimental data.« less
Using 171,173Yb(d,p) to benchmark a surrogate reaction for neutron capture
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hatarik, R; Bersntein, L; Burke, J
2008-08-08
Neutron capture cross sections on unstable nuclei are important for many applications in nuclear structure and astrophysics. Measuring these cross sections directly is a major challenge and often impossible. An indirect approach for measuring these cross sections is the surrogate reaction method, which makes it possible to relate the desired cross section to a cross section of an alternate reaction that proceeds through the same compound nucleus. To benchmark the validity of using the (d,p{gamma}) reaction as a surrogate for (n,{gamma}), the {sup 171,173}Yb(d,p{gamma}) reactions were measured with the goal to reproduce the known [1] neutron capture cross section ratiosmore » of these nuclei.« less
Photoeffect cross sections of several rare-earth elements for 323-keV photons
NASA Astrophysics Data System (ADS)
Umesh, T. K.; Anasuya, S. J.; Shylaja Kumari, J.; Gowda, Channe; Gopinathan Nair, K. P.; Gowda, Ramakrishna
1992-02-01
Total-attenuation cross sections of the oxides of rare-earth elements such as La, Ce, Pr, Nd, Sm, Gd, Dy, Ho, and Er, and also NaNO3 and NaNO2 have been measured in a narrow-beam geometry setup at 323 keV. The total-attenuation cross section for oxygen was obtained as the difference in NaNO3 and NaNO2 cross sections. Using this, the total-attenuation cross sections of the individual lanthanides have been obtained with the aid of the mixture rule. From these, the photoeffect cross sections were derived by subtracting the scattering contribution. These values are found to agree well with Scofield's theoretical data [University of California Report No. UCRL 51326, 1973 (unpublished)].
One-jet inclusive cross section at order a(s)-cubed - Gluons only
NASA Technical Reports Server (NTRS)
Ellis, Stephen D.; Kunszt, Zoltan; Soper, Davison E.
1989-01-01
A complete calculation of the hadron jet cross-section at one order beyond the Born approximation is performed for the simplified case in which there are only gluons. The general structure of the differences from the lowest-order cross-section are described. This step allows two important improvements in the understanding of the theoretical hadron jet cross-section: first, the cross section at this order displays explicit dependence on the jet cone size, so that explicit account can be taken of the differences in jet definitions employed by different experiments; second, the magnitude of the uncertainty of the theoretical cross-section due to the arbitrary choice of the factorization scale has been reduced by a factor of two to three.
Zafred, Paolo R [Murrysville, PA; Draper, Robert [Pittsburgh, PA
2012-01-17
A solid oxide fuel cell (400) is made having a tubular, elongated, hollow, active section (445) which has a cross-section containing an air electrode (452) a fuel electrode (454) and solid oxide electrolyte (456) between them, where the fuel cell transitions into at least one inactive section (460) with a flattened parallel sided cross-section (462, 468) each cross-section having channels (472, 474, 476) in them which smoothly communicate with each other at an interface section (458).
Nuclear reactor control column
Bachovchin, Dennis M.
1982-01-01
The nuclear reactor control column comprises a column disposed within the nuclear reactor core having a variable cross-section hollow channel and containing balls whose vertical location is determined by the flow of the reactor coolant through the column. The control column is divided into three basic sections wherein each of the sections has a different cross-sectional area. The uppermost section of the control column has the greatest cross-sectional area, the intermediate section of the control column has the smallest cross-sectional area, and the lowermost section of the control column has the intermediate cross-sectional area. In this manner, the area of the uppermost section can be established such that when the reactor coolant is flowing under normal conditions therethrough, the absorber balls will be lifted and suspended in a fluidized bed manner in the upper section. However, when the reactor coolant flow falls below a predetermined value, the absorber balls will fall through the intermediate section and into the lowermost section, thereby reducing the reactivity of the reactor core and shutting down the reactor.
The MPI-Mainz UV/VIS Spectral Atlas of Gaseous Molecules of Atmospheric Interest
NASA Astrophysics Data System (ADS)
Sander, Rolf; Keller-Rudek, Hannelore; Moortgat, Geert; Sörensen, Rüdiger
2014-05-01
Measurements from satellites can be used to obtain global concentration maps of atmospheric trace constituents. Critical parameters needed in the analysis of the satellite data are the absorption cross sections of the observed molecules. Here, we present the MPI-Mainz UV/VIS Spectral Atlas, which is a large collection of more than 5000 absorption cross section and quantum yield data files in the ultraviolet and visible (UV/VIS) wavelength region for gaseous molecules and radicals primarily of atmospheric interest. The data files contain results of individual measurements, covering research of almost a whole century. To compare and visualize the data sets, multicoloured graphical representations have been created. The Spectral Atlas is available on the internet at http://www.uv-vis-spectral-atlas-mainz.org. It has been completely overhauled and now appears with improved browse and search options, based on PostgreSQL, Django and Python database software. The web pages are continuously updated.
NASA Technical Reports Server (NTRS)
James, G. K.; Ajello, J. M.; Kanik, I.; Slevin, J.; Franklin, B.; Shemansky, D.
1993-01-01
The electron-atomic hydrogen scattering system is an important testing ground for theoretical models and has received a great deal of attention from experimentalists and theoreticians alike over the years. A complete description of the excitation process requires a knowledge of many different parameters, and experimental measurements of these parameters have been performed in various laboratories around the world. As far as total cross section data are concerned it has been noted that the discrepancy between the data of Long et al. and Williams for n = 2 excitations needs to be resolved in the interests of any further refinement of theory. We report new measurements of total cross sections and atomic line polarizations for both n=2 and n=3 excitations at energies from threshold to 2000 eV...
NASA Astrophysics Data System (ADS)
Yano, Takatomi; 2012B0025 Collaboration; 2014B0126 Collaboration
2017-02-01
Recently, several scientific applications of gadolinium are found in neutrino physics experiments. Gadolinium-157 is the nucleus, which has the largest thermal neutron capture cross-section among all stable nuclei. Gadolinium-155 also has the large cross-section. These neutron capture reactions provide the gamma-ray cascade with the total energy of about 8 MeV. This reaction is applied for several neutrino experiments, e.g. reactor neutrino experiments and Gd doped large water Cherenkov detector experiments, to recognize inverse-beta-decay reaction. A good Gd(n,γ) simulation model is needed to evaluate the detection efficiency of the neutron capture reaction, i.e. the efficiency of IBD detection. In this presentation, we will report the development and study status of a Gd(n,γ) calculation model and comparison with our experimental data taken at ANNRI/MLF beam line, J-PARC.
Quantum molecular dynamics and multistep-direct analyses of multiple preequilibrium emission
NASA Astrophysics Data System (ADS)
Chadwick, M. B.; Chiba, S.; Niita, K.; Maruyama, T.; Iwamoto, A.
1995-11-01
We study multiple preequilibrium emission in nucleon induced reactions at intermediate energies, and compare quantum molecular dynamics (QMD) calculations with multistep-direct Feshbach-Kerman-Koonin results [M. B. Chadwick, P. G. Young, D. C. George, and Y. Watanabe, Phys. Rev. C 50, 996 (1994)]. When the theoretical expressions of this reference are reformulated so that the definitions of primary and multiple emission correspond to those used in QMD, the two theories yield similar results for primary and multiple preequilibrium emission. We use QMD as a tool to determine the multiplicities of fast preequilibrium nucleons as a function of incident energy. For fast particle cross sections to exceed 5% of the inclusive preequilibrium emission cross sections we find that two particles should be included in reactions above 50 MeV, three above about 180 MeV, and four are only needed when the incident energy exceeds about 400 MeV.
NASA Astrophysics Data System (ADS)
Shishko, Victor A.; Konoshonkin, Alexander V.; Kustova, Natalia V.; Borovoi, Anatoli G.
2017-11-01
This work presents the estimation of contribution of the main types of optical beams to the light backscatter for randomly oriented hexagonal ice column, the right dihedral angle of which was distorted within the range of 0° (regular particle) to 10°. Calculations were obtained within the physical optics approximation. The wavelength was 532 nm and the refractive index was 1.3116. The results showed that the total contribution of the main types of optical beams to the total backscattering cross section reach the value of 85% at small distortion angle of the hexagonal column and at substantial distortion angle the total contribution of the main types of optical beams decrease up to 55% of the total backscattering cross section. The obtained conclusions can significantly reduce the calculation time in the case when there is no need for high accuracy of the calculation.
Motivational maturity and helping behavior.
Haymes, M; Green, L
1977-12-01
This study was undertaken to examine the independent influences of conative development (the Maslow needs hierarchy) upon behavioral aspects of prosocial orientations. It provides a behavioral demonstration of conative effects in a helping paradigm, among college-age men. A comparison of the conative data across the ages of 15-22 provided a cross-sectional view of conative development itself. Conative maturity was found to be predictive of greater helping among college-age men. Situational demands were demonstrated which tended to mask, but not override, these predispositional influences on helping. The cross-sectional data on conative development point to probable movement to early esteem concerns among high school men who have reached the conative level of love and belonging. On the other hand, the stability across the years of 15-22 of proportion of safety concerns suggests fixation of such concerns in those exhibiting them in high school. Results are discussed in terms of conative growth for development of prosocial orientations.
Quality of life after percutaneous coronary intervention: part 1.
Cassar, Stephen; R Baldacchino, Donia
Quality of life (QOL) is a complex concept comprised of biopsychosocial, spiritual and environmental dimensions. However, the majority of research addresses only its physical function perspectives. This two-part series examines the holistic perspective of QOL of patients after percutaneous coronary intervention (PCI). Part 1 explains the research process of a cross-sectional descriptive study and its limitations. Data were collected by a mailed WHOQOL-BREF questionnaire in Maltese from a systematic sample of patients who had undergone PCI; the response rate was 64% (n=228; males n=169, females n=59, age 40-89 years). Part 1 also considers limitations, such as its cross-sectional design and retrospective data collection. The hierarchy of human needs theory (Maslow, 1999) guided the study. Part 2 gives the findings on the holistic view of QOL. Having social and family support, as a characteristic of Maltese culture appeared to contribute towards a better QOL.
Job Strain and Ambulatory Blood Pressure: A Meta-Analysis and Systematic Review
Dobson, Marnie; Koutsouras, George; Schnall, Peter
2013-01-01
We reviewed evidence of the relationship between job strain and ambulatory blood pressure (ABP) in 29 studies (1985–2012). We conducted a quantitative meta-analysis on 22 cross-sectional studies of a single exposure to job strain. We systematically reviewed 1 case–control study, 3 studies of cumulative exposure to job strain, and 3 longitudinal studies. Single exposure to job strain in cross-sectional studies was associated with higher work systolic and diastolic ABP. Associations were stronger in men than women and in studies of broad-based populations than those with limited occupational variance. Biases toward the null were common, suggesting that our summary results underestimated the true association. Job strain is a risk factor for blood pressure elevation. Workplace surveillance programs are needed to assess the prevalence of job strain and high ABP and to facilitate workplace cardiovascular risk reduction interventions. PMID:23327240
Traffic congestion and blood pressure elevation: A comparative cross-sectional study in Lebanon.
Bou Samra, Patrick; El Tomb, Paul; Hosni, Mohammad; Kassem, Ahmad; Rizk, Robin; Shayya, Sami; Assaad, Sarah
2017-12-01
This comparative cross-sectional study examines the association between traffic congestion and elevation of systolic and/or diastolic blood pressure levels among a convenience sample of 310 drivers. Data collection took place during a gas station pause at a fixed time of day. Higher average systolic (142 vs 123 mm Hg) and diastolic (87 vs 78 mm Hg) blood pressures were detected among drivers exposed to traffic congestion compared with those who were not exposed (P<.001), while controlling for body mass index, age, sex, pack-year smoking, driving hours per week, and occupational driving. Moreover, among persons exposed to traffic congestion, longer exposure time was associated with higher systolic and diastolic blood pressures. Further studies are needed to better understand the mechanisms of the significant association between elevated blood pressure and traffic congestion. ©2017 Wiley Periodicals, Inc.
NASA Astrophysics Data System (ADS)
Radulović, Vladimir; Trkov, Andrej; Jaćimović, Radojko; Gregoire, Gilles; Destouches, Christophe
2016-12-01
A recent experimental irradiation and measurement campaign using containers made from boron nitride (BN) at the Jožef Stefan Institute (JSI) TRIGA Mark II reactor in Ljubljana, Slovenia, has shown the applicability of BN for neutron spectrum characterization and cross-section validation in the epithermal range through integral activation measurements. The first part of the paper focuses on the determination of the transmission function of a BN container through Monte Carlo calculations and experimental measurements. The second part presents the process of tayloring the sensitivity of integral activation measurements to specific needs and a selection of suitable radiative capture reactions for neutron spectrum characterization in the epithermal range. A BN container used in our experiments and its qualitative effect on the neutron spectrum in the irradiation position employed is displayed in the Graphical abstract.
NASA Technical Reports Server (NTRS)
Thibault, Franck; Boulet, Christian; Ma, Qiancheng
2014-01-01
We present quantum calculations of the relaxation matrix for the Q branch of N2 at room temperature using a recently proposed N2-N2 rigid rotor potential. Close coupling calculations were complemented by coupled states studies at high energies and provide about 10200 two-body state-to state cross sections from which the needed one-body cross-sections may be obtained. For such temperatures, convergence has to be thoroughly analyzed since such conditions are close to the limit of current computational feasibility. This has been done using complementary calculations based on the energy corrected sudden formalism. Agreement of these quantum predictions with experimental data is good, but the main goal of this work is to provide a benchmark relaxation matrix for testing more approximate methods which remain of a great utility for complex molecular systems at room (and higher) temperatures.
Awareness about autism among school teachers in Oman: a cross-sectional study.
Al-Sharbati, Marwan M; Al-Farsi, Yahya M; Ouhtit, Allal; Waly, Mostafa I; Al-Shafaee, Mohamed; Al-Farsi, Omar; Al-Khaduri, Maha; Al-Said, Mona F; Al-Adawi, Samir
2015-01-01
Children with special needs such as those with autism spectrum disorder have been recorded as ostracized and stigmatized in many parts of the world. Little is known about whether such negative views are present among mainstream teachers in Oman. A cross-sectional study was conducted to evaluate school teachers' awareness about autism spectrum disorder in an urban region in Oman. A total of 164 teachers were randomly enrolled from five schools. Misconceptions about autism spectrum disorder were found to be common among mainstream teachers in the country. We posit that such lack of awareness was likely to be rooted with sociocultural patterning as well as conflicting views often "spun" by the scientific community and mass media. Enlightened views toward children with autism spectrum disorder should be presented to Omani teachers to overcome misconceptions and negative attitudes toward children with autism spectrum disorder. © The Author(s) 2013.
Zhou, Wenjie; Ma, Rui; Sharma, Manoj; Zhao, Yong
This article aimed at understanding nutritional knowledge, attitudes, and behaviors of homosexual persons living with HIV/AIDS in Chongqing, China. A cross sectional design using a valid and reliable survey was used. The survey was completed in Chongqing, Southwest China (n = 172). Knowledge of nutrition was deficient regarding sources of nutrients such as calcium and iron, relationships between diet/nutrients and disease, and only 36.1% of participants knew about the Balanced Diet Pagoda for Chinese. Eating habits did not meet the nutritional requirements, and a majority (59.3%) did not eat breakfast every day. The average score on the knowledge quiz was 51.8%. This study showed that homosexual persons with HIV/AIDS in China longed for nutrition knowledge, and this was supported by objective data. Efforts and targeted education programs aiming to improve their nutrition knowledge, attitudes, and behaviors need to be emphasized.
Occupational stress and subclinical atherosclerosis: a systematic review.
Wilson, Mark D; Conroy, Lorraine M; Dorevitch, Samuel
2014-10-01
Stress is a common hazard in the work environment and is associated with multiple adverse health effects. The association between work-related stress (WRS) and cardiovascular disease has been established in a number of epidemiological studies. A systematic review was conducted according to the PRISMA statement of the English literature involving WRS and carotid artery intima media thickness (CIMT). Four cohorts and six cross-sectional studies of occupational stress and CIMT were identified. All cohorts and five of the cross-sectional studies reported a significant positive association, while one reported an inverse association of WRS and CIMT. The weight of the evidence that we were able to identify suggests that occupational stress results in an increased risk of atherosclerosis, assessed via CIMT. Studies that include longitudinal measures of stress and intermediate cardiac endpoints, with adequate accounting for confounders, are needed. Interventional studies should also be conducted to determine whether CIMT progression can be prevented with workplace stress reduction.
Psychological need satisfaction, control, and disordered eating.
Froreich, Franzisca V; Vartanian, Lenny R; Zawadzki, Matthew J; Grisham, Jessica R; Touyz, Stephen W
2017-03-01
Unfulfilled basic psychological needs have been associated with disordered eating behaviours, but the mechanisms underlying that associations are not well understood. This study examined a two-stage path model linking basic psychological need satisfaction to disordered eating behaviours via issues of control. Female university students (N = 323; M age = 19.61), community participants (N = 371; M age = 29.75), and women who self-reported having been diagnosed with an eating disorder (ED; N = 41; M age = 23.88) completed measures of psychological need satisfaction (i.e., autonomy and competence), issues of control (i.e., feelings of ineffectiveness and fear of losing self-control [FLC]), and ED pathology. Path analysis revealed that unsatisfied needs of autonomy and competence were indirectly related to disordered eating behaviours through feelings of ineffectiveness and FLC. The results indicate that issues of control might be one of the mechanisms through which lack of psychological need satisfaction is associated with disordered eating. Although the model was constructed using cross-sectional data, these findings suggest potential targets for prevention and treatment efforts aimed at reducing disordered eating in young females. Our results indicate that young women with chronically unfulfilled basic psychological needs might be vulnerable to developing disordered eating behaviours. The observed patterns suggest that persistent experience of need frustration may engender an internal sense of ineffectiveness and lack of control, which then compels individuals to engage in disordered eating behaviours in an attempt to regain autonomy and competence. Interventions for eating disorders may be most effective when emphasizing the promotion of people's needs for autonomy and competence. Limitations The model was constructed using cross-sectional data. Future experimental and longitudinal studies are needed to confirm the temporal sequence from basic psychological needs to issues of control. The sample only consisted of young women. Further research should explore how thwarting of psychological need satisfaction functions in men. Our clinical sample was small and diagnosis was not confirmed through clinical interview; therefore, those data should be interpreted with caution. © 2016 The British Psychological Society.
Durbin, Anna; Sirotich, Frank; Antoniou, Tony; Roesslein, Kay; Durbin, Janet; Lunsky, Yona
2016-07-01
While community-based mental health services play an important role in caring for persons with HIV (human immunodeficiency virus) and co-existing mental health disorders, the extent to which their support needs are addressed in this setting is unknown. Accordingly, we examined if HIV infection was associated with unmet support needs among men living with and without HIV receiving community mental health care. This cross-sectional study examined 215 men (135 living with HIV and 80 without HIV) receiving case management services in urban Ontario. Using the Camberwell Assessment of Need, we ascertained the prevalence of support needs in 13 domains grouped into three clusters: Basic needs (accommodation, food, benefits, and money management); self-care/functional needs (daytime activities, self-care, and looking after the home); and health/safety needs (physical, psychological distress, psychotic symptoms, safety to self, and safety to others). We used generalized estimating equations with a logit link to examine the association between HIV and unmet need in each domain. Compared to HIV-negative men, men with HIV were more likely to have mood and concurrent disorders, and intellectual and developmental disabilities. Following multivariable analyses, men with HIV had greater unmet needs related to food (odds ratio + 95% confidence interval: 9.36 (4.03, 21.75), p < 0.001); money (OR: 1.90 (1.04, 3.47), p = 0.036) [basic need domains]; psychological distress (OR: 2.39 (1.68, 3.41), p < 0.001); drug use (OR: 5.10 (2.16, 12.08) p < 0.001); and safety to self (OR: 3.35 (1.51, 7.52), p < 0.003) [health and safety domains]. Despite living in a setting with universal health insurance, men with HIV receiving community mental health support had greater unmet need in basic and health domains than HIV-negative men receiving such support. Further research is required to develop and evaluate interventions to best support community-dwelling persons with HIV and mental health disorders.
Three-rooted premolar analyzed by high-resolution and cone beam CT.
Marca, Caroline; Dummer, Paul M H; Bryant, Susan; Vier-Pelisser, Fabiana Vieira; Só, Marcus Vinicius Reis; Fontanella, Vania; Dutra, Vinicius D'avila; de Figueiredo, José Antonio Poli
2013-07-01
The aim of this study was to analyze the variations in canal and root cross-sectional area in three-rooted maxillary premolars between high-resolution computed tomography (μCT) and cone beam computed tomography (CBCT). Sixteen extracted maxillary premolars with three distinct roots and fully formed apices were scanned using μCT and CBCT. Photoshop CS software was used to measure root and canal cross-sectional areas at the most cervical and the most apical points of each root third in images obtained using the two tomographic computed (CT) techniques, and at 30 root sections equidistant from both root ends using μCT images. Canal and root areas were compared between each method using the Student t test for paired samples and 95 % confidence intervals. Images using μCT were sharper than those obtained using CBCT. There were statistically significant differences in mean area measurements of roots and canals between the μCT and CBCT techniques (P < 0.05). Root and canal areas had similar variations in cross-sectional μCT images and became proportionally smaller in a cervical to apical direction as the cementodentinal junction was approached, from where the area then increased apically. Although variation was similar in the roots and canals under study, CBCT produced poorer image details than μCT. Although CBCT is a strong diagnosis tool, it still needs improvement to provide accuracy in details of the root canal system, especially in cases with anatomical variations, such as the three-rooted maxillary premolars.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zeitlin, C.; Guetersloh, S.; Heilbronn, L.
Charge-changing and fragment production cross sections at 0 deg. have been obtained for interactions of 290, 400, and 650 MeV/nucleon {sup 40}Ar beams, 650 and 1000 MeV/nucleon {sup 35}Cl beams, and a 1000 MeV/nucleon {sup 48}Ti beam. Targets of C, CH{sub 2}, Al, Cu, Sn, and Pb were used. Using standard analysis methods, we obtained fragment cross sections for charges as low as 8 for Cl and Ar beams and as low as 10 for the Ti beam. Using data obtained with small-acceptance detectors, we report fragment production cross sections for charges as low as 5, corrected for acceptance usingmore » a simple model of fragment angular distributions. With the lower-charged fragment cross sections, we can compare the data to predictions from several models (including NUCFRG2, EPAX2, and PHITS) in a region largely unexplored in earlier work. As found in earlier work with other beams, NUCFRG2 and PHITS predictions agree reasonably well with the data for charge-changing cross sections, but these models do not accurately predict the fragment production cross sections. The cross sections for the lightest fragments demonstrate the inadequacy of several models in which the cross sections fall monotonically with the charge of the fragment. PHITS, despite its not agreeing particularly well with the fragment production cross sections on average, nonetheless qualitatively reproduces some significant features of the data that are missing from the other models.« less
The Production of FRW Universe and Decay to Particles in Multiverse
NASA Astrophysics Data System (ADS)
Ghaffary, Tooraj
2017-09-01
In this study, first, it will be shown that as the Hubble parameter, " H", increases the production cross section for closed and flat Universes increases rapidly at smaller values of " H" and becomes constant for higher values of " H". However in the case of open Universe, the production cross section has been encountered a singularity. Before this singularity, as the H parameter increases, the cross section increases, for smaller H, ( H < 2.5), exhibits a turn-over at moderate values of H, (2.5 < H < 3.5), decreases for larger amount of H After that and for a special value of H, the cross section has been encountered with a singularity. Although the cross section cannot be defined at this singularity but before and after this point, it is certainly equal to zero. After this singularity, the cross section increases rapidly, when H increases. It is shown that if the production cross section of Universe happens before this singularity, it can't achieve to higher values of Hubble parameter after singularity. More over if the production cross section of Universe situates after the singularity, it won't get access to values of Hubble parameter less than the singularity. After that the thermal distribution for particles inside the FRW Universes are obtained. It is found that a large amount of particles are produced near apparent horizon due to their variety in their energy and their probabilities. Finally, comparing the particle production cross sections for flat, closed and open Universes, it is concluded that as the value of k increases, the cross section decreases.
Poster - 18: New features in EGSnrc for photon cross sections
DOE Office of Scientific and Technical Information (OSTI.GOV)
Ali, Elsayed; Mainegra-Hing, Ernesto; Rogers, Davi
2016-08-15
Purpose: To implement two new features in the EGSnrc Monte Carlo system. The first is an option to account for photonuclear attenuation, which can contribute a few percent to the total cross section at the higher end of the energy range of interest to medical physics. The second is an option to use exact NIST XCOM photon cross sections. Methods: For the first feature, the photonuclear total cross sections are generated from the IAEA evaluated data. In the current, first-order implementation, after a photonuclear event, there is no energy deposition or secondary particle generation. The implementation is validated against deterministicmore » calculations and experimental measurements of transmission signals. For the second feature, before this work, if the user explicitly requested XCOM photon cross sections, EGSnrc still used its own internal incoherent scattering cross sections. These differ by up to 2% from XCOM data between 30 keV and 40 MeV. After this work, exact XCOM incoherent scattering cross sections are an available option. Minor interpolation artifacts in pair and triplet XCOM cross sections are also addressed. The default for photon cross section in EGSnrc is XCOM except for the new incoherent scattering cross sections, which have to be explicitly requested. The photonuclear, incoherent, pair and triplet data from this work are available for elements and compounds for photon energies from 1 keV to 100 GeV. Results: Both features are implemented and validated in EGSnrc.Conclusions: The two features are part of the standard EGSnrc distribution as of version 4.2.3.2.« less
Cross sections for H(-) and Cl(-) production from HCl by dissociative electron attachment
NASA Technical Reports Server (NTRS)
Orient, O. J.; Srivastava, S. K.
1985-01-01
A crossed target beam-electron beam collision geometry and a quadrupole mass spectrometer have been used to conduct dissociative electron attachment cross section measurements for the case of H(-) and Cl(-) production from HCl. The relative flow technique is used to determine the absolute values of cross sections. A tabulation is given of the attachment energies corresponding to various cross section maxima. Error sources contributing to total errors are also estimated.
Measurements of neutron capture cross sections on 70Zn at 0.96 and 1.69 MeV
NASA Astrophysics Data System (ADS)
Punte, L. R. M.; Lalremruata, B.; Otuka, N.; Suryanarayana, S. V.; Iwamoto, Y.; Pachuau, Rebecca; Satheesh, B.; Thanga, H. H.; Danu, L. S.; Desai, V. V.; Hlondo, L. R.; Kailas, S.; Ganesan, S.; Nayak, B. K.; Saxena, A.
2017-02-01
The cross sections of the 70Zn(n ,γ )Zn71m (T1 /2=3.96 ±0.05 -h ) reaction have been measured relative to the 197Au(n ,γ )198Au cross sections at 0.96 and 1.69 MeV using a 7Li(p ,n )7Be neutron source and activation technique. The cross section of this reaction has been measured for the first time in the MeV region. The new experimental cross sections have been compared with the theoretical prediction by talys-1.6 with various level-density models and γ -ray strength functions as well as the tendl-2015 library. The talys-1.6 calculation with the generalized superfluid level-density model and Kopecky-Uhl generalized Lorentzian γ -ray strength function predicted the new experimental cross sections at both incident energies. The 70Zn(n ,γ ) g+m 71Zn total capture cross sections have also been derived by applying the evaluated isomeric ratios in the tendl-2015 library to the measured partial capture cross sections. The spectrum averaged total capture cross sections derived in the present paper agree well with the jendl-4.0 library at 0.96 MeV, whereas it lies between the tendl-2015 and the jendl-4.0 libraries at 1.69 MeV.
NASA Astrophysics Data System (ADS)
Friedman, B.; DuCharme, G.
2017-06-01
We present a semi-empirical scaling law for non-resonant ion-atom single charge exchange cross sections for collisions with velocities from {10}7 {{t}}{{o}} {10}9 {cm} {{{s}}}-1 and ions with positive charge q< 8. Non-resonant cross sections tend to have a velocity peak at collision velocities v≲ 1 {{a}}{{u}} with exponential decay around this peak. We construct a scaling formula for the location of this peak then choose a functional form for the cross section curve and scale it. The velocity at which the cross section peaks, v m, is proportional to the energy defect of the collision, {{Δ }}E, which we predict with the decay approximation. The value of the cross section maximum is proportional to the charge state q, inversely proportional to the target ionization energy I T, and inversely proportional to v m. For the shape of the cross section curve, we use a function that decays exponentially asymptotically at high and low velocities. We scale this function with parameters {v}{{m}},{I}{{T}},{Z}{{T}},{and} {Z}{{P}}, where the {Z}{{T},{{P}}} are the target and projectile atomic numbers. For the more than 100 cross section curves that we use to find the scaling rules, the scaling law predicts cross sections within a little over a factor of 2 on average.
Sonographic evaluation of the greater occipital nerve in unilateral occipital neuralgia.
Cho, John Chin-Suk; Haun, Daniel W; Kettner, Norman W
2012-01-01
Occipital neuralgia is a headache that may result from greater occipital nerve entrapment. Entrapped peripheral nerves typically have an increase in cross-sectional area. The purpose of this study was to measure the cross-sectional area and circumference of symptomatic and asymptomatic greater occipital nerves in patients with unilateral occipital neuralgia and to correlate the greater occipital nerve cross-sectional area with headache severity, sex, and body mass index. Both symptomatic and contralateral asymptomatic greater occipital nerve cross-sectional areas and circumferences were measured by a single examiner using sonography in 17 patients. The Wilcoxon signed rank test and Spearman rank order correlation coefficient were used to analyze the data. Significant differences between the cross-sectional areas and circumferences of the symptomatic and asymptomatic greater occipital nerves were noted (P < .001). No difference existed in cross-sectional area (P = .40) or circumference (P = .10) measurements of the nerves between male and female patients. A significant correlation existed between the body mass index and symptomatic (r = 0.424; P = .045) and asymptomatic (r = 0.443; P = .037) cross-sectional areas. There was no correlation shown between the cross-sectional area of the symptomatic nerve and the severity of Headache Impact Test 6 scores (r = -0.342; P = .179). We report sonographic evidence showing an increased cross-sectional area and circumference of the symptomatic greater occipital nerve in patients with unilateral occipital neuralgia.
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.
NASA Astrophysics Data System (ADS)
Nekab, M.; Kahoul, A.
2006-04-01
We present in this contribution, semi-empirical production cross sections of the main X-ray lines Lα, Lβ and Lγ for elements from Sn to U and for protons with energies varying from 0.5 to 3.0 MeV. The theoretical X-ray production cross sections are firstly calculated from the theoretical ionization cross sections of the L i ( i = 1, 2, 3) subshell within the ECPSSR theory. The semi-empirical Lα, Lβ and Lγ cross sections are then deduced by fitting the available experimental data normalized to their corresponding theoretical values and give the better representation of the experimental data in some cases. On the other hand, the experimental data are directly fitted to deduce the empirical L X-ray production cross sections. A comparison is made between the semi-empirical cross sections, the empirical cross sections reported in this work and the empirical ones reported by Reis and Jesus [M.A. Reis, A.P. Jesus, Atom. Data Nucl. Data Tables 63 (1996) 1] and those of Strivay and Weber [Strivay, G. Weber, Nucl. Instr. and Meth. B 190 (2002) 112].
Measurement of electron impact collisional excitation cross sections of Ni to Ge-like gold
May, M. J.; Beiersdorfer, P.; Jordan, N.; ...
2017-03-01
We have measured the collisional excitation cross sections for the 3d→4f and 3d→5f excitations in Au ions near the Ni-like charge state by using beam plasmas created in the Livermore electron beam ion trap EBIT-I. The cross sections have been experimentally determined at approximately 1, 2 and 3 keV above the threshold energy, ET, for the 3d→4f excitations (ET ~2.5 keV) and at approximately 0.1, 1 and 2 keV above the threshold energy for the 3d→5f excitations (ET ~3.3 keV). The cross section measurements were made possible by using the GSFC x-ray microcalorimeter at the Livermore EBIT facility. The absolutemore » cross sections are determined from the ratio of the intensity of the collisionally excited bound-bound transitions to the intensity of the radiative recombination lines produced in EBIT-I plasmas. The effects of polarization and Auger decay channels are accounted for in the cross section determination. Measured cross sections are compared with those from HULLAC, DWS and FAC calculations. Finally, the measurements demonstrate that some errors exist in the calculated excitation cross sections.« less
Measurement of electron impact collisional excitation cross sections of Ni to Ge-like gold
NASA Astrophysics Data System (ADS)
May, M. J.; Beiersdorfer, P.; Jordan, N.; Scofield, J. H.; Reed, K. J.; Brown, G. V.; Hansen, S. B.; Porter, F. S.; Kelley, R.; Kilbourne, C. A.; Boyce, K. R.
2017-03-01
We have measured the collisional excitation cross sections for the 3d→4f and 3d→5f excitations in Au ions near the Ni-like charge state by using beam plasmas created in the Livermore electron beam ion trap EBIT-I. The cross sections have been experimentally determined at approximately 1, 2 and 3 keV above the threshold energy, ET, for the 3d→4f excitations (ET ˜ 2.5 keV) and at approximately 0.1, 1 and 2 keV above the threshold energy for the 3d→5f excitations (ET ˜ 3.3 keV). The cross section measurements were made possible by using the GSFC x-ray microcalorimeter at the Livermore EBIT facility. The absolute cross sections are determined from the ratio of the intensity of the collisionally excited bound-bound transitions to the intensity of the radiative recombination lines produced in EBIT-I plasmas. The effects of polarization and Auger decay channels are accounted for in the cross section determination. Measured cross sections are compared with those from HULLAC, DWS and FAC calculations. The measurements demonstrate that some errors exist in the calculated excitation cross sections.
Hoffman, Robert L.; Dunham, Jason B.; Hansen, Bruce P.
2012-01-01
Restoration and maintenance of passage for aquatic organisms at road-stream crossings represents a major management priority, involving an investment of hundreds of millions of dollars (for example, U.S. Government Accounting Office, 2001). In recent years, passage at hundreds of crossings has been restored, primarily by replacing barrier road culverts with bridges or stream simulation culverts designed to pass all species and all life stages of aquatic life and simulate natural hydro-geomorphic processes (U.S. Forest Service, 2008). The current situation has motivated two general questions: 1. Are current design standards for stream simulation culverts adequately re-establishing passage for aquatic biota? and 2. How do we monitor and evaluate effectiveness of passage restoration? To address the latter question, a national workshop was held in March 2010, in Portland, Oregon. The workshop included experts on aquatic organism passage from across the nation (see table of participants, APPENDIX) who addressed four classes of methods for monitoring effectiveness of aquatic organism passage—individual movement, occupancy, demography, and genetics. This report has been written, in part, for field biologists who will be undertaking and evaluating the effectiveness of aquatic organism passage restoration projects at road-stream crossings. The report outlines basic methods for evaluating road-stream crossing passage impairment and restoration and discusses under what circumstances and conditions each method will be useful; what questions each method can potentially answer; how to design and implement an evaluation study; and points out the fundamental reality that most evaluation projects will require special funding and partnerships among researchers and resource managers. The report is organized into the following sections, which can be read independently: 1. Historical context: In this section, we provide a brief history of events leading up to the present situation involving aquatic organism passage as a useful context for the issues covered herein. 2. Importance of connectivity for aquatic organisms: In this section, we provide background information regarding the movement characteristics of aquatic organisms and their vulnerability to passage impairment, and the importance of connectivity for a broad diversity of aquatic vertebrates and invertebrates. This section should be useful for practitioners in selecting what species to monitor in relation to aquatic organism passage. 3. Methods for evaluating aquatic organism passage: In this section, we present a range of perspectives on alternatives for assessing and monitoring aquatic organism passage impairment and the effectiveness of passage restoration actions, including the following methods: Individual Movement, Occupancy Models, Abundance (Demography), and Molecular Genetic Markers. 4. Relevance, strengths, and limitations of the four methods: In this section, we discuss the utility of each of the methods as a tool for assessing and quantifying passage impairment and restoration effectiveness. 5. Guidelines for selecting a method: In this section, we review some fundamental criteria and guidelines to consider when selecting a method for monitoring in the context of answering three important questions that should be addressed when developing a plan for evaluating aquatic organism passage. 6. Study and monitoring design considerations: In this section, we discuss four key design elements that need to be considered when developing a monitoring design for assessing passage impairment and restoration. The basic objectives of the report are to: 1. Review the movement characteristics of five groups of aquatic organisms that inhabit streams and to assess their general vulnerability to passage impairment at road-stream crossings; 2. Review four methods for monitoring aquatic organism passage impairment and the effectiveness of actions to restore passage at road-stream crossing structures; 3. Assess the relevance, strengths, and limitations of each method as a monitoring tool; 4. Identify and discuss guidelines that will be useful for selecting a monitoring method; and 5. Discuss what we have identified as the four key elements that need to be considered when developing a monitoring design for assessing passage impairment and restoration at road-stream crossings.
2010-01-01
Background The two primary objectives of this study were to the assess consultation load of occupational health physicians (OHPs), and their difficulties and needs with regard to their sickness certification tasks in sick-listed employees with severe medical unexplained physical symptoms (MUPS). Third objective was to determine which disease-, patient-, doctor- and practice-related factors are associated with the difficulties and needs of the OHPs. Methods In this cross-sectional study, 43 participating OHPs from 5 group practices assessed 489 sick-listed employees with and without severe MUPS. The OHPs filled in a questionnaire about difficulties concerning sickness certification tasks, consultation time, their needs with regard to consultation with or referral to a psychiatrist or psychologist, and communication with GPs. The OHPs also completed a questionnaire about their personal characteristics. Results OHPs only experienced task difficulties in employees with severe MUPS in relation to their communication with the treating physician. This only occured in cases in which the OHP attributed the physical symptoms to somatoform causes. If they attributed the physical symptoms to mental causes, the OHPs reported a need to consultate a psychiatrist about the diagnosis and treatment. Conclusions OHPs experience few difficulties with their sickness certification tasks and consultation load concerning employees with severe MUPS. However, they encounter problems if the diagnostic uncertainties of the treating physician interfere with the return to work process. OHPs have a need for psychiatric expertise whenever they are uncertain about the psychiatric causes of a delayed return to work process. We recommend further training programs for OHPs. They should also have more opportunity for consultation and referral to a psychiatrist, and their communication with treating physicians should be improved. PMID:21059232
Untreated head and neck surgical disease in Sierra Leone: a cross-sectional, countrywide survey.
Van Buren, Nicholas C; Groen, Reinou S; Kushner, Adam L; Samai, Mohamed; Kamara, Thaim B; Ying, Jian; Meier, Jeremy D
2014-10-01
Demonstrate how the Surgeons OverSeas Assessment of Surgical Need (SOSAS) can be used to determine the burden of head and neck (H&N) surgical disease in developing countries and identify reasons for untreated disease. Cluster randomized, cross-sectional, countrywide survey. Sierra Leone. The survey was administered to 75 of 9671 enumeration areas in Sierra Leone between January 9 and February 3, 2012, with 25 households in each cluster randomly selected for the survey. A household representative and 2 randomly selected household members were interviewed. Need for surgical care was based on participants' responses to whether they had an H&N condition that they believed needed surgical care. Of 1875 households, data were analyzed for 1843 (98%), with 3645 total respondents. Seven hundred and one H&N surgical conditions were reported as occurring during the lifetime of the 3645 respondents (19.2%).The current prevalence of H&N conditions in need of a surgical consultation was 11.8%. No money (60.1%) was the most common reason respondents reported for not receiving medical care. A bivariate analysis demonstrated that age, village type, education, and type of condition may be predictors for seeking health care and/or receiving surgical care. These results show limited access for patients to be evaluated for a potential H&N surgical condition in Sierra Leone. The true incidence of untreated surgical disease is unknown as most respondents were not evaluated by a surgeon. This survey could be used in other countries as health care professionals assess surgical needs throughout the world. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2014.
Need for an (n,α) Apparatus at the LANSCE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Koehler, Paul E.
2014-03-05
There is an urgent need for a new (n,α) measurement capability at the Los Alamos Neutrons Science Center (LANSCE) for several reasons. First, it has been shown that (n,α) measurements on medium- to heavy-mass nuclides can provide some of the best constraints on some of the most important reaction rates for explosive nucleosynthesis studies. A few such measurements have been made, but many more are needed. Second, there are a few (n,p) and (n,α) cross sections on lighter nuclides of importance to nuclear astrophysics that remain unmeasured. Third, it has been shown that (n,α) measurements can constrain photon strength functionsmore » (PSFs) at very low energies. This is important because recent experiments, theory, and astrophysical calculations have demonstrated that enhanced PSFs at these energies can have large impacts on nucleosynthesis occurring in explosive environments. Also, enhanced low-energy PSFs could have significant impact on (n,γ) cross sections of interest to radiochemical diagnostics of nuclear devices. However, the shape of PSFs at low energies is a subject of considerable controversy, so new data are badly needed. Fourth, previous (n,α) data have revealed a number of puzzles and hints of exotic atomic-nuclear interactions. In addition to being interesting in their own light, these interactions could be important for understanding high-energy-density environments such as in nuclear explosion and at the National Ignition Facility. Simulations indicate that the high neutron flux at the Manuel Lujan Jr. Neutron Scattering Center (MLNSC) at the LANSCE will make many more of the needed measurements feasible. Hence, a new (n,α) instrument at the MLNSC would enable a wide range of important and interesting basic and applied science.« less
Richter, Marlise; Chersich, Matthew F; Vearey, Jo; Sartorius, Benn; Temmerman, Marleen; Luchters, Stanley
2014-02-01
Intersections between migration and sex work are underexplored in southern Africa, a region with high internal and cross-border population mobility, and HIV prevalence. Sex work often constitutes an important livelihood activity for migrant women. In 2010, sex workers trained as interviewers conducted cross-sectional surveys with 1,653 female sex workers in Johannesburg (Hillbrow and Sandton), Rustenburg and Cape Town. Most (85.3%) sex workers were migrants (1396/1636): 39.0% (638/1636) internal and 46.3% (758/1636) cross-border. Cross-border migrants had higher education levels, predominately worked part-time, mainly at indoor venues, and earned more per client than other groups. They, however, had 41% lower health service contact (adjusted odds ratio = 0.59; 95% confidence interval = 0.40-0.86) and less frequent condom use than non-migrants. Police interaction was similar. Cross-border migrants appear more tenacious in certain aspects of sex work, but require increased health service contact. Migrant-sensitive, sex work-specific health care and health education are needed.
NASA Astrophysics Data System (ADS)
Pritychenko, B.; Mughabghab, S. F.
2012-12-01
We present calculations of neutron thermal cross sections, Westcott factors, resonance integrals, Maxwellian-averaged cross sections and astrophysical reaction rates for 843 ENDF materials using data from the major evaluated nuclear libraries and European activation file. Extensive analysis of newly-evaluated neutron reaction cross sections, neutron covariances, and improvements in data processing techniques motivated us to calculate nuclear industry and neutron physics quantities, produce s-process Maxwellian-averaged cross sections and astrophysical reaction rates, systematically calculate uncertainties, and provide additional insights on currently available neutron-induced reaction data. Nuclear reaction calculations are discussed and new results are presented. Due to space limitations, the present paper contains only calculated Maxwellian-averaged cross sections and their uncertainties. The complete data sets for all results are published in the Brookhaven National Laboratory report.
NASA Astrophysics Data System (ADS)
Wang, C.-K.; Liao, W.-H.; Wu, H.-M.; Lo, Y.-H.; Lin, T.-R.; Tung, Y.-C.
2017-11-01
Polydimethylsiloxane (PDMS) has become a widely used material to construct microfluidic devices for various biomedical and chemical applications due to its desirable material properties and manufacturability. PDMS microfluidic devices are usually fabricated using soft lithography replica molding methods with master molds made of photolithogrpahy patterned photoresist layers on silicon wafers. The fabricated microfluidic channels often have rectangular cross-sectional geometries with single or multiple heights. In this paper, we develop a single step sequential PDMS wet etching process that can be used to fabricate microfluidic channels with various cross-sectional geometries from single-layer PDMS microfluidic channels. The cross-sections of the fabricated channel can be non-rectangular, and varied along the flow direction. Furthermore, the fabricated cross-sectional geometries can be numerically simulated beforehand. In the experiments, we fabricate microfluidic channels with various cross-sectional geometries using the developed technique. In addition, we fabricate a microfluidic mixer with alternative mirrored cross-sectional geometries along the flow direction to demonstrate the practical usage of the developed technique.
NASA Technical Reports Server (NTRS)
Nieman, R. A.
1971-01-01
The charge exchange cross sections for protons and various alkali atoms are calculated using the classical approximation of Gryzinski. It is assumed that the hydrogen atoms resulting from charge exchange exist in all possible excited states. Charge transfer collisions between protons and potassium as well as protons and sodium atoms are studied. The energy range investigated is between 4 and 30 keV. The theoretical calculations of the capture cross section and the cross section for the creation of metastable 2S hydrogen are compared to experimental values. Good quantitative agreement is found for the capture cross section but only qualitative agreement for the metastable cross section. Analysis of the Lyman alpha window in molecular oxygen suggests that measured values of the metastable cross section may be in error. Thick alkali target data are also presented. This allows the determination of the total electron loss cross section. Finally, some work was done with H2(+).
Angular distributions for H- formation in single collisions of H+ on Mg
NASA Astrophysics Data System (ADS)
Alvarez, I.; Cisneros, C.; Russek, A.
1982-07-01
Absolute differential cross sections have been measured for H- formation in single collisions of H+ on Mg in the energy range from 0.5 to 5.0 keV. Total cross sections, obtained by direct integration of these differential cross sections, are in good agreement with earlier total-cross-section measurements of Morgan and Eriksen in the energy range common to the two experiments and are in good agreement with the calculated total cross sections of Olson and Liu. The differential cross sections are strongly peaked in the forward direction. The functional form and scaling properties of this forward peak strongly indicate that it is a glory maximum, which occurs when the classical deflection function changes over from attractive to repulsive at some finite impact parameter. The differential cross sections from 1.0 to 5.0 keV show no other structure, but below 1.0 keV a τ-dependent structure is observed which becomes more pronounced as the collision energy decreases. 1982 The American Physical Society.