An Examination of Cross Sectional Change in Student's Metaphorical Perceptions towards Heat, Temperature and Energy Concepts

ERIC Educational Resources Information Center

Celik, Harun

2016-01-01

In science teaching, metaphors are important tools for understanding meaningful learning and conceptual formation by the help of daily life language. This study aims to evaluate how the concepts of heat, temperature and energy are perceived by students in secondary school science classes and how the perceptions of these concepts vary in terms of…

Study of an advanced transport airplane design concept known as Flatbed

NASA Technical Reports Server (NTRS)

Smethers, R. G.; Caldwell, E. W.; Warnock, W. E.; Wilson, J. M., Jr.

1980-01-01

The design concept and configuration of the Flatbed transport aircraft are presented. The Flatbed configuration combines into one frame, the ability to haul cargo, virtually unrestrained by cross sectional dimensions of the fuselage. The feasibility and capability of the Flatbed is discussed in depth.

Interactions in hydrogen of relativistic neon to nickel projectiles: Total charge-changing cross sections

NASA Astrophysics Data System (ADS)

Chen, C.-X.; Albergo, S.; Caccia, Z.; Costa, S.; Crawford, H. J.; Cronqvist, M.; Engelage, J.; Ferrando, P.; Fonte, R.; Greiner, L.; Guzik, T. G.; Insolia, A.; Jones, F. C.; Knott, C. N.; Lindstrom, P. J.; Mitchell, J. W.; Potenza, R.; Romanski, J.; Russo, G. V.; Soutoul, A.; Testard, O.; Tull, C. E.; Tuvé, C.; Waddington, C. J.; Webber, W. R.; Wefel, J. P.; Zhang, X.

1994-06-01

A liquid hydrogen target was used to study the nuclear fragmentation of beams of relativistic heavy ions, 22Ne to 58Ni, over an energy range 400 to 900 MeV/nucleon. The experiments were carried out at the Lawrence Berkeley Laboratory Bevalac HISS facility, using the charge-velocity-rigidity method to identify the charged fragments. Here we describe the general concept of the experiment and present total charge-changing cross sections obtained from 17 separate runs. These new measured cross sections display an energy dependence which follows semiempirical model predictions. The mass dependence of the cross sections behaves as predicted by optical models, but within the experimental energy range, the optical model parameters display a clear energy dependence. The isospin of the projectile nuclei also appears to be an important factor in the interaction process.

Piano Students' Conceptions of Musical Scores as External Representations: A Cross-Sectional Study

ERIC Educational Resources Information Center

Bautista, Alfredo; Perez Echeverria, Ma del Puy; Pozo, J. Ignacio; Brizuela, Barbara M.

2009-01-01

Musical scores are some of the most important learning tools for musicians' acquisition of musical knowledge. However, despite their educational relevance, very little is known about how music students "conceive" of these cultural external representations. Given that these conceptions might act as mediators of students' learning…

On the use of the cross section concept as applied to pulsed CO2 laser dynamics

NASA Technical Reports Server (NTRS)

Flamant, P. H.; Menzies, R. T.

1985-01-01

The 'cross sections' which are commonly used in combination with the molecular vibrational level densities to describe induced transition rates are time dependent in a pulsed discharge. This greatly affects the relative rates of buildup of radiation at the various lines of a molecular gain medium in a nondispersive cavity, and the consequences for line selection by injection in a TEA-CO2 laser are discussed.

Alternative approximation concepts for space frame synthesis

NASA Technical Reports Server (NTRS)

Lust, R. V.; Schmit, L. A.

1985-01-01

A structural synthesis methodology for the minimum mass design of 3-dimensionall frame-truss structures under multiple static loading conditions and subject to limits on displacements, rotations, stresses, local buckling, and element cross-sectional dimensions is presented. A variety of approximation concept options are employed to yield near optimum designs after no more than 10 structural analyses. Available options include: (A) formulation of the nonlinear mathematcal programming problem in either reciprocal section property (RSP) or cross-sectional dimension (CSD) space; (B) two alternative approximate problem structures in each design space; and (C) three distinct assumptions about element end-force variations. Fixed element, design element linking, and temporary constraint deletion features are also included. The solution of each approximate problem, in either its primal or dual form, is obtained using CONMIN, a feasible directions program. The frame-truss synthesis methodology is implemented in the COMPASS computer program and is used to solve a variety of problems. These problems were chosen so that, in addition to exercising the various approximation concepts options, the results could be compared with previously published work.

i-TED: A novel concept for high-sensitivity (n,γ) cross-section measurements

NASA Astrophysics Data System (ADS)

Domingo-Pardo, C.

2016-07-01

A new method for measuring (n , γ) cross-sections aiming at enhanced signal-to-background ratio is presented. This new approach is based on the combination of the pulse-height weighting technique with a total energy detection system that features γ-ray imaging capability (i-TED). The latter allows one to exploit Compton imaging techniques to discriminate between true capture γ-rays arising from the sample under study and background γ-rays coming from contaminant neutron (prompt or delayed) captures in the surrounding environment. A general proof-of-concept detection system for this application is presented in this paper together with a description of the imaging method and a conceptual demonstration based on Monte Carlo simulations.

Special Course on Fundamentals of Fighter Aircraft Design

DTIC Science & Technology

1987-10-01

mounted centrally on a cylindrical fuselage of circular cross-section. Here the fuselage interference is shown by a calculation with an exact...M. and Schiff, L.B., "Aerodynamic Mathematical Modeling - Basic Concepts", AGARD-LS-114, 1981, Lecture 1. 30. Malcolm, G.N., "Rotary and Magnus ...thin cylindrical Intake 1.5.3. Real Intake equivalence 1.5.4. Lip thickness and auxiliary intake design 1.6. AIR INTAKE RADAR CROSS SECTION (R.C.S

Mathematics Undergraduate Student Teachers' Conceptions of Guided Inductive and Deductive Teaching Approaches

ERIC Educational Resources Information Center

Ndemo, Zakaria; Zindi, Fred; Mtetwa, David

2017-01-01

This contribution aimed at developing an understanding of student teachers' conceptions of guided discovery teaching approaches. A cross-sectional survey design involving eleven secondary mathematics teachers who had enrolled for an in-service mathematics education degree was used to address the research question: What are undergraduate student…

Comparison of different liquid hydrogen tank integration concepts for the ELAC-1 research configuration

NASA Astrophysics Data System (ADS)

Albus, J.; Oery, H.

1993-04-01

One of the main problems associated with the structural design of a hypersonic aircraft is the conception of the cryogenic tank. Therefore two essential questions, in consideration of structural weight, volumetric efficiency and the aspects as well of inspection, maintenance and repair, as of exchangeability in case of leakage (leak before burst) and safety in operation, have to be answered. These questions concern the choice of the tank integration concept and the tank cross section. To get an idea how much the take-off weight depends on the tank integration concept, at the Institut fuer Leichtbau of the RWTH Aachen a program for weight estimation of hypersonic aircraft has been developed. Herewith the goal was to define well suited substitute models which allow the performance of parametric studies within a wide range of parameters in a tolerable amount of time. In the following the mass model and calculation methods used will be shortly introduced and finally the results achieved will be presented and discussed. On this occasion also comments on structural efficiency of different tank cross sections will be given.

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.

Absence of nonresponse bias in a study of sport-caught Great Lakes fish consumption and conception failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stein, A.D.; Tay, E.; Courval, J.M.

1999-04-01

The authors have reported that men`s lifetime sport-caught Great Lakes fish consumption was associated with lifetime prevalence of conception delay or failure. Those cross-sectional data were based on responses to a postal questionnaire. The present study was conducted to evaluate whether nonresponse bias could explain the cross-sectional findings. The authors conducted telephone interviews with 230 men and 38 women who did not respond to the original responders with respect to key demographic, behavioral, and reproductive characteristics. Nonresponders were approximately 1.5 years older at interview, were more likely to be Caucasian, and reported higher incomes than responders. Among men, nonresponders hadmore » fished fewer days in the past year. Almost one half of nonresponders reported no fish consumption in the past year, compared to one quarter of responders. Nonresponders were more likely than responders to have ever conceived a live-born child, had more children, and were less likely to intend to have additional children in the next 5 years. Among both responders and nonresponders there was an increased prevalence of a period of conception failure among men who reported consuming greater quantities of sport-caught Great Lakes fish. The study provides support for the cross-sectional analyses presented previously, insofar as nonresponse bias is unlikely to have a major role in the observed association.« less

Measurement of the 242Pu neutron capture cross section

NASA Astrophysics Data System (ADS)

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

2015-10-01

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

Partial wave analysis for folded differential cross sections

NASA Astrophysics Data System (ADS)

Machacek, J. R.; McEachran, R. P.

2018-03-01

The value of modified effective range theory (MERT) and the connection between differential cross sections and phase shifts in low-energy electron scattering has long been recognized. Recent experimental techniques involving magnetically confined beams have introduced the concept of folded differential cross sections (FDCS) where the forward (θ ≤ π/2) and backward scattered (θ ≥ π/2) projectiles are unresolved, that is the value measured at the angle θ is the sum of the signal for particles scattered into the angles θ and π - θ. We have developed an alternative approach to MERT in order to analyse low-energy folded differential cross sections for positrons and electrons. This results in a simplified expression for the FDCS when it is expressed in terms of partial waves and thereby enables one to extract the first few phase shifts from a fit to an experimental FDCS at low energies. Thus, this method predicts forward and backward angle scattering (0 to π) using only experimental FDCS data and can be used to determine the total elastic cross section solely from experimental results at low-energy, which are limited in angular range.

Estimating onset time from longitudinal and cross-sectional data with an application to estimating gestational age from longitudinal maternal anthropometry during pregnancy and neonatal anthropometry at birth.

PubMed

Ortega-Villa, Ana Maria; Grantz, Katherine L; Albert, Paul S

2018-06-01

Determining the date of conception is important for estimating gestational age and monitoring whether the fetus and mother are on track in their development and pregnancy. Various methods based on ultrasound have been proposed for dating a pregnancy in high resource countries. However, such techniques may not be available in under-resourced countries. We develop a shared random parameter model for estimating the date of conception using longitudinal assessment of multiple maternal anthropometry and cross-sectional neonatal anthropometry. The methodology is evaluated with a training-test set paradigm as well as with simulations to examine the robustness of the method to model misspecification. We illustrate this new methodology with data from the NICHD Fetal Growth Studies.

WRAP-RIB antenna technology development

NASA Technical Reports Server (NTRS)

Freeland, R. E.; Garcia, N. F.; Iwamoto, H.

1985-01-01

The wrap-rib deployable antenna concept development is based on a combination of hardware development and testing along with extensive supporting analysis. The proof-of-concept hardware models are large in size so they will address the same basic problems associated with the design fabrication, assembly and test as the full-scale systems which were selected to be 100 meters at the beginning of the program. The hardware evaluation program consists of functional performance tests, design verification tests and analytical model verification tests. Functional testing consists of kinematic deployment, mesh management and verification of mechanical packaging efficiencies. Design verification consists of rib contour precision measurement, rib cross-section variation evaluation, rib materials characterizations and manufacturing imperfections assessment. Analytical model verification and refinement include mesh stiffness measurement, rib static and dynamic testing, mass measurement, and rib cross-section characterization. This concept was considered for a number of potential applications that include mobile communications, VLBI, and aircraft surveillance. In fact, baseline system configurations were developed by JPL, using the appropriate wrap-rib antenna, for all three classes of applications.

The Trajectory of Elementary and Middle School Students' Perceptions of the Concept of History

ERIC Educational Resources Information Center

Altun, Adnan

2014-01-01

The current study aims to reveal the trajectory (change) of the perception of the concept of history during elementary and middle school years through students' responses to the question, "What is history in your opinion?" The cross-sectional research design was the preferred method to provide stronger opportunity for the current study…

Structural efficiency studies of corrugated compression panels with curved caps and beaded webs

NASA Technical Reports Server (NTRS)

Davis, R. C.; Mills, C. T.; Prabhakaran, R.; Jackson, L. R.

1984-01-01

Curved cross-sectional elements are employed in structural concepts for minimum-mass compression panels. Corrugated panel concepts with curved caps and beaded webs are optimized by using a nonlinear mathematical programming procedure and a rigorous buckling analysis. These panel geometries are shown to have superior structural efficiencies compared with known concepts published in the literature. Fabrication of these efficient corrugation concepts became possible by advances made in the art of superplastically forming of metals. Results of the mass optimization studies of the concepts are presented as structural efficiency charts for axial compression.

Learning Illustrated: An Exploratory Cross-Sectional Drawing Analysis of Students' Conceptions of Learning

ERIC Educational Resources Information Center

Hsieh, Wen-Min; Tsai, Chin-Chung

2018-01-01

Using the draw-a-picture technique, the authors explored the learning conceptions held by students across grade levels. A total of 1,067 Taiwanese students in Grades 2, 4, 6, 8, 10, and 12 participated in this study. Participants were asked to use drawing to illustrate how they conceptualize learning. A coding checklist was developed to analyze…

The Influence of Cooperative Education and Reflection upon Previous Work Experiences on University Graduates' Vocational Self-Concept

ERIC Educational Resources Information Center

Drewery, David; Nevison, Colleen; Pretti, T. Judene

2016-01-01

Purpose: The purpose of this paper is to assess the relative effects of participation in cooperative education (co-op) and engagement in reflection upon previous work experiences on undergraduate students' vocational self-concept (VSC) at graduation. Design/methodology/approach: A cross-sectional survey of graduating students (n = 1,483) from a…

Material dependence of 2H(d,p)3H cross section at the very low energies

NASA Astrophysics Data System (ADS)

Kılıç, Ali İhsan; Czerski, Konrad; Kuştan-Kılıç, Fadime; Targosz-Sleczka, Natalia; Weissbach, Daniel; Huke, Armin; Ruprecht, Götz

2017-09-01

Calculations of the material dependence of 2H(d,p)3H cross section and neutron-to-proton branching ratio of d+d reactions have been performed including a concept of the 0+ threshold single particle resonance. The resonance has been assumed to explain the enhanced electron screening effect observed in the d+d reaction for different metallic targets. Here, we have included interference effects between the flat and resonance part of the cross section, which allowed us to enlighten observed suppression of the neutron channel in some metals such as Sr and Li. Since the position of the resonance depends on the screening energy that strongly depends on the local electron density. The resonance width, observed for the d+d reactions in the very hygroscopic metals (Sr and Li) and therefore probably contaminated by oxides, should be much larger than for other metals. Thus, the interference term of the cross section depending on the total resonance width provides the material dependences.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, C.; Albergo, S.; Caccia, Z.

A liquid hydrogen target was used to study the nuclear fragmentation of beams of relativistic heavy ions, [sup 22]Ne to [sup 58]Ni, over an energy range 400 to 900 MeV/nucleon. The experiments were carried out at the Lawrence Berkeley Laboratory Bevalac HISS facility, using the charge-velocity-rigidity method to identify the charged fragments. Here we describe the general concept of the experiment and present total charge-changing cross sections obtained from 17 separate runs. These new measured cross sections display an energy dependence which follows semiempirical model predictions. The mass dependence of the cross sections behaves as predicted by optical models, butmore » within the experimental energy range, the optical model parameters display a clear energy dependence. The isospin of the projectile nuclei also appears to be an important factor in the interaction process.« less

Nomadic concepts in the history of biology.

PubMed

Surman, Jan; Stráner, Katalin; Haslinger, Peter

2014-12-01

The history of scientific concepts has firmly settled among the instruments of historical inquiry. In our section we approach concepts from the perspective of nomadic concepts (Isabelle Stengers). Instead of following the evolution of concepts within one disciplinary network, we see them as subject to constant reification and change while crossing and turning across disciplines and non-scientific domains. This introduction argues that understanding modern biology is not possible without taking into account the constant transfers and translations that affected concepts. We argue that this approach does not only engage with nomadism between disciplines and non-scientific domains, but reflects on and involves the metaphoric value of concepts as well. Copyright © 2014 Elsevier Ltd. All rights reserved.

Descriptive Developmental Research: Why Only Time?

ERIC Educational Resources Information Center

Labouvie, Erich W.

1975-01-01

The usefulness of the concepts of cohort and time of measurement in descriptive developmental research was examined by comparing the time-specific cross-sectional and cohort-specific longitudinal age gradients of stable and unstable children. (Author/ED)

Structural Configuration Systems Analysis for Advanced Aircraft Fuselage Concepts

NASA Technical Reports Server (NTRS)

Mukhopadhyay, Vivek; Welstead, Jason R.; Quinlan, Jesse R.; Guynn, Mark D.

2016-01-01

Structural configuration analysis of an advanced aircraft fuselage concept is investigated. This concept is characterized by a double-bubble section fuselage with rear mounted engines. Based on lessons learned from structural systems analysis of unconventional aircraft, high-fidelity finite-element models (FEM) are developed for evaluating structural performance of three double-bubble section configurations. Structural sizing and stress analysis are applied for design improvement and weight reduction. Among the three double-bubble configurations, the double-D cross-section fuselage design was found to have a relatively lower structural weight. The structural FEM weights of these three double-bubble fuselage section concepts are also compared with several cylindrical fuselage models. Since these fuselage concepts are different in size, shape and material, the fuselage structural FEM weights are normalized by the corresponding passenger floor area for a relative comparison. This structural systems analysis indicates that an advanced composite double-D section fuselage may have a relative structural weight ratio advantage over a conventional aluminum fuselage. Ten commercial and conceptual aircraft fuselage structural weight estimates, which are empirically derived from the corresponding maximum takeoff gross weight, are also presented and compared with the FEM- based estimates for possible correlation. A conceptual full vehicle FEM model with a double-D fuselage is also developed for preliminary structural analysis and weight estimation.

Staff Perspectives on the Use of a Computer-Based Concept for Lifestyle Intervention Implemented in Primary Health Care

ERIC Educational Resources Information Center

Carlfjord, Siw; Johansson, Kjell; Bendtsen, Preben; Nilsen, Per; Andersson, Agneta

2010-01-01

Objective: The aim of this study was to evaluate staff experiences of the use of a computer-based concept for lifestyle testing and tailored advice implemented in routine primary health care (PHC). Design: The design of the study was a cross-sectional, retrospective survey. Setting: The study population consisted of staff at nine PHC units in the…

Portuguese Primary School Children's Conceptions about Digestion: Identification of Learning Obstacles. Research Report

ERIC Educational Resources Information Center

Carvalho, Graca; Silva, Rui; Lima, Nelson; Coquet, Eduarda; Clement, Pierre

2004-01-01

A cross-sectional study of Portuguese primary school pupils' conceptions on digestion and the digestive tract was carried out before and after teaching this topic. Pupils of the prior four school years (5/6 to 9/10 year old) drew what happens to a cookie inside their body. In some cases they also wrote a short text or were interviewed. To identify…

Future Scenarios in Communications. [Student's Guide.] Preparing for Tomorrow's World.

ERIC Educational Resources Information Center

Iozzi, Louis A.; And Others

The purpose of this module is to introduce students (grades 7-8) to the concept of change and factors influencing change. The module is composed of two major sections. Section 1 examines the development of the telephone system in the United States and introduces four futures forecasting techniques (Delphi probe, cross-impact matrix, trend…

Digitalization in roll forming manufacturing

NASA Astrophysics Data System (ADS)

Sedlmaier, A.; Dietl, T.; Ferreira, P.

2017-09-01

Roll formed profiles are used in automotive chassis production as building blocks for the body-in-white. The ability to produce profiles with discontinuous cross sections, both in width and in depth, allows weight savings in the final automotive chassis through the use of load optimized cross sections. This has been the target of the 3D Roll Forming process. A machine concept is presented where a new forming concept for roll formed parts in combination with advanced robotics allowing freely positioned roll forming tooling in 3D space enables the production of complex shapes by roll forming. This is a step forward into the digitalization of roll forming manufacturing by making the process flexible and capable of rapid prototyping and production of small series of parts. Moreover, data collection in a large scale through the control system and integrated sensors lead to an increased understanding of the process and provide the basis to develop self-optimizing roll forming machines, increasing the productivity, quality and predictability of the roll-forming process. The first parts successfully manufactured with this new forming concept are presented.

Examining the progression and consistency of thermal concepts: a cross-age study

NASA Astrophysics Data System (ADS)

Adadan, Emine; Yavuzkaya, Merve Nur

2018-03-01

This cross-sectional study examined how the progression and consistency of students' understanding of thermal concepts in everyday contexts changes across the grade levels. A total of 656 Turkish students from Grade 8 (age 13-14), Grade 10 (age 15-16), and the first year of college (age 19-20) participated in the study. The data were analysed using statistical procedures (descriptive and inferential). Findings indicated a substantial progression in the students' scientific understanding of thermal concepts across grade levels. In addition, the students' alternative conceptions about thermal concepts generally decreased in frequency across grade levels, but certain alternative conceptions were observed in every grade level to a similar extent. Even though the number of students who consistently used scientific ideas increased across grade levels, the number of students who consistently used non-scientific ideas decreased across grade levels. However, the number of students who used scientific and non-scientific ideas inconsistently generally increased as they progressed in the science curriculum. These findings can be associated with either fragmentation or alternative conceptions that result from the gradual enrichment processes students experience when they try to integrate scientific concepts into their conceptual frameworks.

The self-adjusting file (SAF). Part 1: respecting the root canal anatomy--a new concept of endodontic files and its implementation.

PubMed

Metzger, Zvi; Teperovich, Ehud; Zary, Raviv; Cohen, Raphaela; Hof, Rafael

2010-04-01

To introduce a new concept, the self-adjusting file (SAF), and discuss its unique features compared with current rotary nickel-titanium file systems. The SAF file is hollow and designed as a thin cylindrical nickel-titanium lattice that adapts to the cross-section of the root canal. A single file is used throughout the procedure. It is inserted into a path initially prepared by a # 20 K-file and operated with a transline- (in-and-out) vibration. The resulting circumferential pressure allows the file's abrasive surface to gradually remove a thin uniform hard-tissue layer from the entire root canal surface, resulting in a canal with a similar cross-section but of larger dimensions. This holds also for canals with an oval or flat cross-section, which will be enlarged to a flat or oval cross-section of larger dimensions. The straightening of curved canals is also reduced because of the high pliability of the file and the absence of a rigid metal core. Thus, the original shape of the root canal is respected both longitudinally and in cross-section. The hollow SAF file is operated with a constant flow of irrigant that enters the full length of the canal and that is activated by the vibration and is replaced continuously throughout the procedure. This results in effective cleaning even at the cul de sac apical part of the canal. The SAF has high mechanical endurance; file separation does not occur; and mechanical failure, if it occurs, is limited to small tears in the latticework. The SAF represents a new step forward in endodontic file development that may overcome many of the shortcomings of current rotary nickel-titanium file systems. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Investigating Children's Conceptions of the Brain: First Steps

ERIC Educational Resources Information Center

Bartoszeck, Amauri Betini; Bartoszeck, Flavio Kulevicz

2012-01-01

This paper reports data, part of a cross-sectional study about the use of pupil's drawings as a means of probing the development of 195 Brazilian pre-school children (4 to 6 year-olds) and 681 primary school pupils 1st Grade through 4th Grade (7 to 10 years of age) conceptions of the human brain. The aims of the present study is to analyze how the…

Design concepts for pressurized lunar shelters utilizing indigenous materials

NASA Technical Reports Server (NTRS)

Happel, John Amin; Willam, Kaspar; Shing, Benson

1991-01-01

The objective is to design a pressurized shelter build of indigenous lunar material. The topics are presented in viewgraph form and include the following: lunar conditions which impact design; secondary factors; review of previously proposed concepts; cross section of assembly facility; rationale for indigenous materials; indigenous material choices; cast basalt properties; design variables; design 1, cylindrical segments; construction sequence; design 2, arch-slabs with post-tensioned ring girders; and future research.

Concept for a large multi-mission amphibian aircraft

NASA Technical Reports Server (NTRS)

Vaughan, J. C., III; Earl, T. D.

1979-01-01

A very large aircraft has been proposed for meeting both civil cargo and military transport needs for 1995 and beyond. The concept includes a wide noncircular fuselage cross section with a low wing, thick inner wing section, fuselage-mounted engines, and an air cushion landing gear. The civil freighter operates independently of congested passenger airports, using sheltered water as a runway and a waterfront land site for parking and ground operations. The military transport can operate from a wide variety of surfaces and temporary bases. The air cushion landing gear weighs substantially less than conventional gear and permits the use of extended takeoff distance resulting in improved payload/gross weight ratio.

Multidimensional Sexual Perfectionism and Female Sexual Function: A Longitudinal Investigation.

PubMed

Stoeber, Joachim; Harvey, Laura N

2016-11-01

Research on multidimensional sexual perfectionism differentiates four forms: self-oriented, partner-oriented, partner-prescribed, and socially prescribed. Self-oriented sexual perfectionism reflects perfectionistic standards people apply to themselves as sexual partners; partner-oriented sexual perfectionism reflects perfectionistic standards people apply to their sexual partner; partner-prescribed sexual perfectionism reflects people's beliefs that their sexual partner imposes perfectionistic standards on them; and socially prescribed sexual perfectionism reflects people's beliefs that society imposes such standards on them. Previous studies found partner-prescribed and socially prescribed sexual perfectionism to be maladaptive forms of sexual perfectionism associated with a negative sexual self-concept and problematic sexual behaviors, but only examined cross-sectional relationships. The present article presents the first longitudinal study examining whether multidimensional sexual perfectionism predicts changes in sexual self-concept and sexual function over time. A total of 366 women aged 17-69 years completed measures of multidimensional sexual perfectionism, sexual esteem, sexual anxiety, sexual problem self-blame, and sexual function (cross-sectional data). Three to six months later, 164 of the women completed the same measures again (longitudinal data). Across analyses, partner-prescribed sexual perfectionism emerged as the most maladaptive form of sexual perfectionism. In the cross-sectional data, partner-prescribed sexual perfectionism showed positive relationships with sexual anxiety, sexual problem self-blame, and intercourse pain, and negative relationships with sexual esteem, desire, arousal, lubrication, and orgasmic function. In the longitudinal data, partner-prescribed sexual perfectionism predicted increases in sexual anxiety and decreases in sexual esteem, arousal, and lubrication over time. The findings suggest that partner-prescribed sexual perfectionism contributes to women's negative sexual self-concept and female sexual dysfunction.

Theoretical study of the ionospheric G factor

NASA Technical Reports Server (NTRS)

Hagenbuch, K. M.

1972-01-01

A derivation from kinetic theory of the energy balance equation used in wave interaction work is reviewed. Then G is defined and two models for G are presented: one, a model based on Gerjuoy-Stein cross sections for both O2 and N2; the other based on a more recent model for O2 cross sections. The two models differ considerably in their temperature dependence. The limits of applicability of the useful energy balance equation (hence of the concept of G) are discussed and it is found that no difficulty arises unless the transmitter power is more than 1000 times that now employed at the present operating frequency.

Ergodicity of financial indices

NASA Astrophysics Data System (ADS)

Kolesnikov, A. V.; Rühl, T.

2010-05-01

We introduce the concept of the ensemble averaging for financial markets. We address the question of equality of ensemble and time averaging in their sequence and investigate if these averagings are equivalent for large amount of equity indices and branches. We start with the model of Gaussian-distributed returns, equal-weighted stocks in each index and absence of correlations within a single day and show that even this oversimplified model captures already the run of the corresponding index reasonably well due to its self-averaging properties. We introduce the concept of the instant cross-sectional volatility and discuss its relation to the ordinary time-resolved counterpart. The role of the cross-sectional volatility for the description of the corresponding index as well as the role of correlations between the single stocks and the role of non-Gaussianity of stock distributions is briefly discussed. Our model reveals quickly and efficiently some anomalies or bubbles in a particular financial market and gives an estimate of how large these effects can be and how quickly they disappear.

Ultra wide band 3-D cross section (RCS) holography

NASA Astrophysics Data System (ADS)

Collins, H. D.; Hall, T. E.

1992-07-01

Ultra wide band impulse holography is an exciting new concept for predictive radar cross section (RCS) evaluation employing near-field measurements. Reconstruction of the near-field hologram data maps the target's scattering areas, and uniquely identifies the 'hot spot' locations on the target. In addition, the target and calibration sphere's plane wave angular spectrums are computed (via digital algorithm) and used to generate the target's far-field RCS values in three dimensions for each frequency component in the impulse. Thin and thick targets are defined in terms of their near-field amplitude variations in range. Range gating and computer holographic techniques are applied to correct these variations. Preliminary experimental results on various targets verify the concept of RCS holography. The unique 3-D presentation (i.e., typically containing 524,288 RCS values for a 1024 (times) 512 sampled aperture for every frequency component) illustrates the efficacy of target recognition in terms of its far-field plane wave angular spectrum image. RCS images can then be viewed at different angles for target recognition, etc.

A cross-sectional study of drinking patterns, prelicensure nursing education, and professional identity formation.

PubMed

Hensel, Desiree; Middleton, Mary Jean; Engs, Ruth C

2014-05-01

Professional identity has been described as being an important outcome of nursing education, but how this identity forms is not well understood. Even less is known about how students' personal substance use/abuse patterns factor into their professional identity formation. The purpose of this study was to describe drinking behaviors and professional identity formation among baccalaureate of nursing students. This cross-sectional, descriptive study used a survey design. The study took place on three campuses of a large system university in the Midwestern United States. The convenience sample consisted of 333 students enrolled in the first semester of the second, third, and last year of a traditional baccalaureate of nursing program. Data were collected using the Nurse Self-Concept Questionnaire and the Student Alcohol Questionnaire. ANOVA and Pearson r statistical tests were used to analyze data. Self-perceptions related to leadership were found to be the weakest aspect of the students' self-concepts, and the only dimensions of professional self-concept that differed significantly among students enrolled at varying program levels were knowledge and communication. A negative relationship was found between increased alcohol use and general self-concept and communication, but the associations were very weak. More research is needed to understand how best to facilitate the acquisition of an identity consistent with the profession's values and how to recruit candidates that embody nursing's preferred future. © 2013.

A survey on clinical governance awareness among clinical staff: a cross-sectional study.

PubMed

Ravaghi, Hamid; Zarnaq, Rahim Khodayari; Adel, Amin; Badpa, Mahnaz; Adel, Moein; Abolhassani, Nazanin

2014-06-25

Clinical Governance (CG) program has been raised in Iran in order to improve the quality of clinical care. The purpose of this study is to investigate the awareness of clinical governance program among clinical staff working in selected teaching hospitals in Tehran, Iran. To investigate the CG awareness, a cross-sectional survey was conducted among 345 clinical staff working in 20 selected public hospitals in Tehran. Data were gathered using the standardized clinical governance awareness questionnaire. Descriptive statistics were used to analyze the data. The results showed that the level of staff awareness about the concept of CG was low. They perceived continuous quality improvement, responsibility, medical errors reduction and patient safety as the main concepts of the CG framework. Reaching agreement of standards concepts among staff and positive changes in attitudes were considered as two most observed changes. The main perceived barriers to the implementation of clinical governance included lack of proper management and leadership, lack of full support, inappropriate organizational culture, lack of knowledge, poor communication system and insufficient training. The concepts and goals of clinical governance have not been effectively conveyed to the staff and despite its implementation in the hospitals, there has been low clinical governance awareness among the staff. Clinical Governance must be implemented through comprehensive management support and participation of all staff and health professionals at both hospital and policy making level.

Antiproton-Hydrogen Atom Annihilation.

DTIC Science & Technology

1986-05-01

Morgan, Jr., Concepts for the Design of an Antimatter Annihilation ’Rocket, Journal of the British Interplanetary Society 35, 405 (1982). 2. D.L. Morgan...Matter- Antimatter Annihilation, Phys. Rev. D 2, 1389 (1970). (Notes: results for p - H are equivalent to 5 -H; the bare + p annihilation cross section is

Motivational Interviewing Skills are Positively Associated with Nutritionist Self-Efficacy

ERIC Educational Resources Information Center

Marley, Scott C.; Carbonneau, Kira; Lockner, Donna; Kibbe, Debra; Trowbridge, Frederick

2011-01-01

Objective: To examine the relationships between physical and social self-concepts, motivational interviewing (MI), and nutrition assessment skills with dimensions of counseling self-efficacy. Design: Cross-sectional survey. Setting: Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinics. Participants: Sixty-five WIC…

Development of a New Unmanned Semi- Submersible (USS) Vehicle

DTIC Science & Technology

2010-06-01

radio systems. All of the concept hulls fall into the categories of semi-submersible hull types and semi- floater hull types. Both hulls have the bulk...of their volume below the water surface. The semi- floater would have a large cross-section of surface expression whereas the semi-submersible would

Development of the Levey-Nowak Embedded Librarian Presence Instrument: A Preliminary Study

ERIC Educational Resources Information Center

Levey, Janet A.; Nowak, Karen L.

2015-01-01

A cross-sectional descriptive design was used to examine the initial psychometric properties and feasibility of the newly developed Levey-Nowak Embedded Librarian Presence Instrument. The instrument was structured by a literature review identifying reoccurring concepts of presence, helpfulness, confidence, and collaboration within the embedded…

Education in Urban Areas. Cross-National Dimensions.

ERIC Educational Resources Information Center

Stromquist, Nelly P., Ed.

This book provides a collection of articles that covers urban education from both developed and developing countries. It presents five studies focused on the United States and other industrialized countries, two studies on Asia, two on Africa, and one on Latin American. Major sections discuss concepts and trends in urban education, the…

Entropic Damping of the Motion of a Piston

ERIC Educational Resources Information Center

Mungan, Carl E.

2017-01-01

The concept of an "entropic force" can be introduced by considering a familiar setup, namely a horizontal cylinder enclosing an ideal monatomic gas by a piston of cross-sectional area "A" and mass "m" that can slide without friction. The surrounding atmospheric pressure P[subscript atm] keeps the piston from flying…

COGITA network has constructed a glossary of diagnostic reasoning terms.

PubMed

Barais, Marie; Hauswaldt, Johannes; Dinant, Geert-Jan; van de Wiel, Margje; Stolper, C F Erik; Van Royen, Paul

2017-12-01

The role of gut feelings in diagnostic reasoning is recognized by most GPs throughout Europe, and probably throughout the world. Studies on this topic have emerged from different countries but there is the risk that authors will use different terms for similar concepts. The European Expert Group on Cognitive and Interactive Processes in Diagnosis and Management in General Practice, COGITA for short, was founded in 2008 to conduct cross-border research in the area of non-analytical diagnostic reasoning. Academic GPs, PhD students, psychologists, linguists and students meet once a year to share their experiences, exchange results and initiate new studies on the topic. A milestone in their research is this publication of a short glossary of diagnostic reasoning terms relating to the gut feelings research topic. It was constructed by the COGITA group members following a literature review, which aimed to define salient terms used in their publications. They described the terms, cross-reviewed the wording and reached consensus within the group. Two sections were created: (1) a diagnostic reasoning section that describes concepts such as analytical and non-analytical reasoning, clinical mind lines, and intuition, and (2) a research methods section describing concepts such as linguistic validity and saturation. The glossary, including relevant literature, has been published on the website http://www.gutfeelingsingeneralpractice.eu . In the future, the glossary will be modified if necessary and completed by members of the COGITA group. [Box: see text].

Relativistic effects in ab initio electron-nucleus scattering

NASA Astrophysics Data System (ADS)

Rocco, Noemi; Leidemann, Winfried; Lovato, Alessandro; Orlandini, Giuseppina

2018-05-01

The electromagnetic responses obtained from Green's function Monte Carlo (GFMC) calculations are based on realistic treatments of nuclear interactions and currents. The main limitations of this method comes from its nonrelativistic nature and its computational cost, the latter hampering the direct evaluation of the inclusive cross sections as measured by experiments. We extend the applicability of GFMC in the quasielastic region to intermediate momentum transfers by performing the calculations in a reference frame that minimizes nucleon momenta. Additional relativistic effects in the kinematics are accounted for employing the two-fragment model. In addition, we developed a novel algorithm, based on the concept of first-kind scaling, to compute the inclusive electromagnetic cross section of 4He through an accurate and reliable interpolation of the response functions. A very good agreement is obtained between theoretical and experimental cross sections for a variety of kinematical setups. This offers a promising prospect for the data analysis of neutrino-oscillation experiments that requires an accurate description of nuclear dynamics in which relativistic effects are fully accounted for.

Designing tools for oil exploration using nuclear modeling

NASA Astrophysics Data System (ADS)

Mauborgne, Marie-Laure; Allioli, Françoise; Manclossi, Mauro; Nicoletti, Luisa; Stoller, Chris; Evans, Mike

2017-09-01

When designing nuclear tools for oil exploration, one of the first steps is typically nuclear modeling for concept evaluation and initial characterization. Having an accurate model, including the availability of accurate cross sections, is essential to reduce or avoid time consuming and costly design iterations. During tool response characterization, modeling is benchmarked with experimental data and then used to complement and to expand the database to make it more detailed and inclusive of more measurement environments which are difficult or impossible to reproduce in the laboratory. We present comparisons of our modeling results obtained using the ENDF/B-VI and ENDF/B-VII cross section data bases, focusing on the response to a few elements found in the tool, borehole and subsurface formation. For neutron-induced inelastic and capture gamma ray spectroscopy, major obstacles may be caused by missing or inaccurate cross sections for essential materials. We show examples of the benchmarking of modeling results against experimental data obtained during tool characterization and discuss observed discrepancies.

Why Do Silver Trimers Intercalated in DNA Exhibit Unique Nonlinear Properties That Are Promising for Applications?

PubMed

Bonačić-Koutecký, Vlasta; Perić, Martina; Sanader, Željka

2018-05-17

Our investigation of one-photon absorption (OPA) and nonlinear optical (NLO) properties such as two-photon absorption (TPA) of silver trimer intercalated in DNA based on TDDFT approach allowed us to propose a mechanism responsible for large TPA cross sections of such NLO-phores. We present a concept that illustrates the key role of quantum cluster as well as of nucleotide bases from the immediate neighborhood. For this purpose, different surroundings consisting of guanine-cytosine and adenine-thymine such as (GCGC) and (ATAT) have been investigated that are exhibiting substantially different values of TPA cross sections. This has been confirmed by extending the immediate surroundings as well as using the two-layer quantum mechanics/molecular mechanics (QM/MM) approach. We focus on the cationic closed-shell system and illustrate that the neutral open-shell system shifts OPA spectra into the NIR regime, which is suitable for applications. Thus, in this contribution, we propose novel NLO-phores inducing large TPA cross sections, opening the route for multiphoton imaging.

Getting to know me: social role experiences and age differences in self-concept clarity during adulthood.

PubMed

Lodi-Smith, Jennifer; Roberts, Brent W

2010-10-01

The current research had 2 aims: (1) to determine the cross-sectional age differences in self-concept clarity during adulthood and (2) to examine the importance of social role experiences for age differences in self-concept clarity. These aims were addressed in 2 large samples of adults ranging in age from 18 to 94 years. In both studies, self-concept clarity had a curvilinear relation to age such that self-concept clarity was positively related to age from young adulthood through middle age and negatively related to age in older adulthood. This relationship was moderated by annual income and community investment. In addition, annual income and health-related social role limitations mediated age differences in self-concept clarity. Findings are discussed in terms of modern theories of identity development.

Tomographic sensing and localization of fluorescently labeled circulating cells in mice in vivo

NASA Astrophysics Data System (ADS)

Zettergren, Eric; Swamy, Tushar; Runnels, Judith; Lin, Charles P.; Niedre, Mark

2012-07-01

Sensing and enumeration of specific types of circulating cells in small animals is an important problem in many areas of biomedical research. Microscopy-based fluorescence in vivo flow cytometry methods have been developed previously, but these are typically limited to sampling of very small blood volumes, so that very rare circulating cells may escape detection. Recently, we described the development of a ‘diffuse fluorescence flow cytometer’ (DFFC) that allows sampling of much larger blood vessels and therefore circulating blood volumes in the hindlimb, forelimb or tail of a mouse. In this work, we extend this concept by developing and validating a method to tomographically localize circulating fluorescently labeled cells in the cross section of a tissue simulating optical flow phantom and mouse limb. This was achieved using two modulated light sources and an array of six fiber-coupled detectors that allowed rapid, high-sensitivity acquisition of full tomographic data sets at 10 Hz. These were reconstructed into two-dimensional cross-sectional images using Monte Carlo models of light propagation and the randomized algebraic reconstruction technique. We were able to obtain continuous images of moving cells in the sample cross section with 0.5 mm accuracy or better. We first demonstrated this concept in limb-mimicking optical flow photons with up to four flow channels, and then in the tails of mice with fluorescently labeled multiple myeloma cells. This approach increases the overall diagnostic utility of our DFFC instrument.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peter H. Titus and Ali Zolfaghari

A critical design feature of any tokamak is the space taken up by the inner leg of the toroidal field (TF) coil. The radial build needed for the TF inner leg, along with shield thickness , size of the central solenoid and plasma minor radius set the major radius of the machine. The cost of the tokamak core roughly scales with the cube of the major radius. Small reductions in the TF build can have a big impact on the overall cost of the reactor. The cross section of the TF inner leg must structurally support the centering force andmore » that portion of the vertical separating force that is not supported by the outer structures. In this paper, the TF inner leg equatorial plane cross sections are considered. Out-of- Plane (OOP) forces must also be supported, but these are largest away from the equatorial plane, in the inner upper and lower corners and outboard sections of the TF coil. OOP forces are taken by structures that are not closely coupled with the radial build of the central column at the equatorial plane. The "Vertical Access AT Pilot Plant" currently under consideration at PPPL is used as a starting point for the structural, field and current requirements. Other TF structural concepts are considered. Most are drawn from existing designs such as ITER's circular conduits in radial plates bearing on a heavy nose section, and TPX's square conduits in a case, Each of these concepts can rely on full wedging, or partial wedging. Vaulted TF coils are considered as are those with some component of bucking against a central solenoid or bucking post. With the expectation that the pilot plant will be a steady state machine, a static stress criteria is used for all the concepts. The coils are assumed to be superconducting, with the superconductor not contributing to the structural strength. Limit analysis is employed to assess the degree of conservatism in the static criteria as it is applied to a linear elastic stress analysis. TF concepts, and in particular the PPPL AT PILOT plate concept are evaluated based on amount of space needed for structure and the amount of space left for superconductor.« less

Predicting sugar-sweetened behaviours with theory of planned behaviour constructs: Outcome and process results from the SIPsmartER behavioural intervention.

PubMed

Zoellner, Jamie M; Porter, Kathleen J; Chen, Yvonnes; Hedrick, Valisa E; You, Wen; Hickman, Maja; Estabrooks, Paul A

2017-05-01

Guided by the theory of planned behaviour (TPB) and health literacy concepts, SIPsmartER is a six-month multicomponent intervention effective at improving SSB behaviours. Using SIPsmartER data, this study explores prediction of SSB behavioural intention (BI) and behaviour from TPB constructs using: (1) cross-sectional and prospective models and (2) 11 single-item assessments from interactive voice response (IVR) technology. Quasi-experimental design, including pre- and post-outcome data and repeated-measures process data of 155 intervention participants. Validated multi-item TPB measures, single-item TPB measures, and self-reported SSB behaviours. Hypothesised relationships were investigated using correlation and multiple regression models. TPB constructs explained 32% of the variance cross sectionally and 20% prospectively in BI; and explained 13-20% of variance cross sectionally and 6% prospectively. Single-item scale models were significant, yet explained less variance. All IVR models predicting BI (average 21%, range 6-38%) and behaviour (average 30%, range 6-55%) were significant. Findings are interpreted in the context of other cross-sectional, prospective and experimental TPB health and dietary studies. Findings advance experimental application of the TPB, including understanding constructs at outcome and process time points and applying theory in all intervention development, implementation and evaluation phases.

Be the Volume: A Classroom Activity to Visualize Volume Estimation

ERIC Educational Resources Information Center

Mikhaylov, Jessica

2011-01-01

A hands-on activity can help multivariable calculus students visualize surfaces and understand volume estimation. This activity can be extended to include the concepts of Fubini's Theorem and the visualization of the curves resulting from cross-sections of the surface. This activity uses students as pillars and a sheet or tablecloth for the…

Contact, Attitude and Motivation in the Learning of Catalan at Advanced Levels

ERIC Educational Resources Information Center

Hamilton, Colleen; Serrano, Raquel

2015-01-01

The theoretical complexity of current understandings of second language (L2) identity has brought the study of language learning motivations from basic concepts of intrinsic, integrative and instrumental motives to a more dynamic construct that interacts with background factors, learning contexts and proficiency levels. This cross-sectional study…

Students' Ideas and Attitudes about Air Quality

ERIC Educational Resources Information Center

Skamp, Keith; Boyes, Eddie; Stanisstreet, Martin

2004-01-01

The results of a large scale (N=1001) cross-sectional (Years 6, 8 and 10) study of students' ideas about the composition of unpolluted air, the nature of air pollution, the biological consequences of air pollution, and about acid rain and the Greenhouse Effect are reported. A range of persistent alternative conceptions were identified, in some…

Young Children's Conceptions of Science and Scientists

ERIC Educational Resources Information Center

Lee, Tiffany R.

2010-01-01

This study explores young children's images of science and scientists, their sources for scientific knowledge, and the nature of their science-related experiences. A cross-sectional design was used to study how students' ideas differ over the first three years of elementary school. A modified version of the Draw-a-Scientist Test (DAST) and a…

Nuclear Analysis

NASA Technical Reports Server (NTRS)

Clement, J. D.; Kirby, K. D.

1973-01-01

Exploratory calculations were performed for several gas core breeder reactor configurations. The computational method involved the use of the MACH-1 one dimensional diffusion theory code and the THERMOS integral transport theory code for thermal cross sections. Computations were performed to analyze thermal breeder concepts and nonbreeder concepts. Analysis of breeders was restricted to the (U-233)-Th breeding cycle, and computations were performed to examine a range of parameters. These parameters include U-233 to hydrogen atom ratio in the gaseous cavity, carbon to thorium atom ratio in the breeding blanket, cavity size, and blanket size.

A method for (n,alpha) and (n,p) cross section measurements using a lead slowing-down spectrometer

NASA Astrophysics Data System (ADS)

Thompson, Jason Tyler

The need for nuclear data comes from several sources including astrophysics, stockpile stewardship, and reactor design. Photodisintegration, neutron capture, and charged particle out reactions on stable or short-lived radioisotopes play crucial roles during stellar evolution and forming solar isotopic abundances whereas these reactions can affect the safety of our national weapons stockpile or criticality and safety calculations for reactors. Although models can be used to predict some of these values, these predictions are only as good as the experimental data that constrains them. For neutron-induced emission of α particles and protons ((n,α) and (n,p) reactions) at energies below 1 MeV, the experimental data is at best scarce and models must rely on extrapolations from unlike situations, (i.e. different reactions, isotopes, and energies) providing ample room for uncertainty. In this work a new method of measuring energy dependent (n,α) and (n,p) cross sections was developed for the energy range of 0.1 eV - ˜100 keV using a lead slowing-down spectrometer (LSDS). The LSDS provides a ˜10 4 neutron flux increase over the more conventionally used time-of-flight (ToF) methods at equivalent beam conditions, allowing for the measurement of small cross sections (µb’s to mb’s) while using small sample masses (µg’s to mg’s). Several detector concepts were designed and tested, including specially constructed Canberra passivated, implanted, planar silicon (PIPS) detectors; and gas-electron-multiplier (GEM) foils. All designs are compensated to minimize γ-flash problems. The GEM detector was found to function satisfactory for (n,α) measurements, but the PIPS detectors were found to be better suited for (n,p) reaction measurements. A digital data acquisition (DAQ) system was programmed such that background can be measured simultaneously with the reaction cross section. Measurements of the 147Sm(n,α)144Nd and 149 Sm(n,α)146Nd reaction cross sections were performed as proofs of concept. The measurement of 147Sm verified and extended a previous measurement while the measurement of 149Sm is the first over the majority of the 0.1 eV to 100 keV energy region.

Inter-Satellite Communications Considerations and Requirements for Distributed Spacecraft and Formation Flying Systems

NASA Technical Reports Server (NTRS)

Kwadrat, Carl F.; Horne, William D.; Edwards, Bernard L.

2002-01-01

In order to avoid selecting inadequate inter-spacecraft cross-link communications standards for Distributed Spacecraft System (DSS) missions, it is first necessary to identify cross-link communications strategies and requirements common to a cross-section of proposed missions. This paper addresses the cross-link communication strategies and requirements derived from a survey of 39 DSS mission descriptions that are projected for potential launch within the next 20 years. The inter-spacecraft communications strategies presented are derived from the topological and communications constraints from the DSS missions surveyed. Basic functional requirements are derived from an analysis of the fundamental activities that must be undertaken to establish and maintain a cross-link between two DSS spacecraft. Cross-link bandwidth requirements are derived from high-level assessments of mission science objectives and operations concepts. Finally, a preliminary assessment of possible cross-link standards is presented within the context of the basic operational and interoperability requirements.

Modeling spanwise nonuniformity in the cross-sectional analysis of composite beams

NASA Astrophysics Data System (ADS)

Ho, Jimmy Cheng-Chung

Spanwise nonuniformity effects are modeled in the cross-sectional analysis of beam theory. This modeling adheres to an established numerical framework on cross-sectional analysis of uniform beams with arbitrary cross-sections. This framework is based on two concepts: decomposition of the rotation tensor and the variational-asymptotic method. Allowance of arbitrary materials and geometries in the cross-section is from discretization of the warping field by finite elements. By this approach, dimensional reduction from three-dimensional elasticity is performed rigorously and the sectional strain energy is derived to be asymptotically-correct. Elastic stiffness matrices are derived for inputs into the global beam analysis. Recovery relations for the displacement, stress, and strain fields are also derived with care to be consistent with the energy. Spanwise nonuniformity effects appear in the form of pointwise and sectionwise derivatives, which are approximated by finite differences. The formulation also accounts for the effects of spanwise variations in initial twist and/or curvature. A linearly tapered isotropic strip is analyzed to demonstrate spanwise nonuniformity effects on the cross-sectional analysis. The analysis is performed analytically by the variational-asymptotic method. Results from beam theory are validated against solutions from plane stress elasticity. These results demonstrate that spanwise nonuniformity effects become significant as the rate at which the cross-sections vary increases. The modeling of transverse shear modes of deformation is accomplished by transforming the strain energy into generalized Timoshenko form. Approximations in this transformation procedure from previous works, when applied to uniform beams, are identified. The approximations are not used in the present work so as to retain more accuracy. Comparison of present results with those previously published shows that these approximations sometimes change the results measurably and thus are inappropriate. Static and dynamic results, from the global beam analysis, are calculated to show the differences between using stiffness constants from previous works and the present work. As a form of validation of the transformation procedure, calculations from the global beam analysis of initially twisted isotropic beams from using curvilinear coordinate axes featuring twist are shown to be equivalent to calculations using Cartesian coordinates.

Effects of track structure and cell inactivation on the calculation of heavy ion mutation rates in mammalian cells

NASA Technical Reports Server (NTRS)

Cucinotta, F. A.; Wilson, J. W.; Shavers, M. R.; Katz, R.

1996-01-01

It has long been suggested that inactivation severely effects the probability of mutation by heavy ions in mammalian cells. Heavy ions have observed cross sections of inactivation that approach and sometimes exceed the geometric size of the cell nucleus in mammalian cells. In the track structure model of Katz the inactivation cross section is found by summing an inactivation probability over all impact parameters from the ion to the sensitive sites within the cell nucleus. The inactivation probability is evaluated using the dose-response of the system to gamma-rays and the radial dose of the ions and may be equal to unity at small impact parameters for some ions. We show how the effects of inactivation may be taken into account in the evaluation of the mutation cross sections from heavy ions in the track structure model through correlation of sites for gene mutation and cell inactivation. The model is fit to available data for HPRT mutations in Chinese hamster cells and good agreement is found. The resulting calculations qualitatively show that mutation cross sections for heavy ions display minima at velocities where inactivation cross sections display maxima. Also, calculations show the high probability of mutation by relativistic heavy ions due to the radial extension of ions track from delta-rays in agreement with the microlesion concept. The effects of inactivation on mutations rates make it very unlikely that a single parameter such as LET or Z*2/beta(2) can be used to specify radiation quality for heavy ion bombardment.

Suicidal and nonsuicidal adolescents: different factors contribute to self-esteem.

PubMed

Grøholt, Berit; Ekeberg, Oivind; Wichstrøm, Lars; Haldorsen, Tor

2005-10-01

Some risk and protective factors differ in their importance to suicidal and nonsuicidal people. In this research we explore the cross-sectional differences between risk factors among suicidal adolescents and nonsuicidal adolescents by focusing on self-esteem. Sixty-five suicidal and 390 nonsuicidal adolescents were compared on Harter's Self-Perceived Profile for Adolescents, self-concept stability, seeking support, loneliness, and depression. Self-concept stability, loneliness, and peer support correlated differently with self-esteem. In multivariate regression analyses, variance in self-esteem was explained by depression and loneliness, and among nonsuicidal adolescents also by self-concept stability, support, and competencies. Loneliness and self-concept stability related differently to self-esteem in suicidal and nonsuicidal adolescents. When the aim is to enhance self-esteem, this difference may delineate suicidal subgroups that need special interventions.

Review of research on the health of caregiving grandparents.

PubMed

Grinstead, Linda Nicholson; Leder, Sharon; Jensen, Susan; Bond, Linda

2003-11-01

To provide a critical review of research literature on the health of grandparents raising grandchildren, and identify directions for future research. Approaches used to access the research studies for this review included a comprehensive search using relevant electronic databases and a thorough examination of the references in each published study. All studies but one were published after 1990. Samples consisted primarily of African-American and Caucasian grandmothers in the United States of America. Earlier studies tended to describe health and other related concepts while more recent studies began to examine relationships between concepts. Most of the studies had a cross-sectional design and only one evaluated interventions. Inconsistencies in the results of these studies were prevalent. Evaluation studies, longitudinal designs, and more varied study samples including cross-cultural comparisons are needed to advance knowledge about grandparent caregivers' health.

Academic and Family Conditions Associated with Intrinsic Academic Motivation in Japanese Medical Students: A Pilot Study

ERIC Educational Resources Information Center

Tanaka, Masaaki; Watanabea, Yasuyoshi

2012-01-01

Objective: Intrinsic academic motivation is one of the most important psychological concepts in education, and it is related to academic outcomes in medical students. This study examined the relationships between academic and family conditions and intrinsic academic motivation. Design: Cross-sectional design. Setting: The study group consisted of…

Cross Section Calculations and Comparison to Experiment

NASA Technical Reports Server (NTRS)

Townsend, L. W.; Ford, W. P.; Dewet, W. C.; Werneth, C. M.

2016-01-01

Understanding fragmentation of galactic cosmic ray nuclei in collisions within spacecraft structures and human tissues is an important element in assessing biological risk to crew members from this radiation source. Over the past four decades, various models have been developed to describe these important processes. Some models invoke semi-classical concepts based upon geometric descriptions of collisions between spherical nuclei.

The Emergence of a Learning Progression in Middle School Chemistry

ERIC Educational Resources Information Center

Johnson, Philip; Tymms, Peter

2011-01-01

Previously, a small scale, interview-based, 3-year longitudinal study (ages 11-14) in one school had suggested a learning progression related to the concept of a substance. This article presents the results of a large-scale, cross-sectional study which used Rasch modeling to test the hypothesis of the learning progression. Data were collected from…

The Relationship between Moral Decision Making and Patterns of Consolidation and Transition in Moral Judgment Development.

ERIC Educational Resources Information Center

Thoma, Stephen J.; Rest, James R.

1999-01-01

Assessed the relationship between a measure of consolidation and transition in moral-judgment development and utility of moral concepts in sociomoral decision making in multiple cross-sectional and longitudinal samples. Found that participants' reliance on a Kohlbergian moral framework was highest during periods of consolidation and lowest during…

The Cognitive Developmental Approach to "Epistemology" and Its Relation to Logical and Moral Stages.

ERIC Educational Resources Information Center

Broughton, John

This paper presents a cross-sectional investigation of adolescents' and young adults' reflective epistemological development. Three groups of 8 subjects (4 male and female) ages 10, 14, and 18 were given Piagetian tasks, the Kohlberg moral judgment questionnaire, and an epistemology interview covering such concepts as knowledge, thought, feeling,…

Technological Change, Employment, Qualifications and Training. A Development of Concepts from a Conference Held in Berlin, November 24-26, 1982.

ERIC Educational Resources Information Center

Sorge, Arndt

A conference examined the socioeconomic challenges of technological and educational change throughout the European community. One hundred fifty representatives from a cross section of countries and agencies involved in education, training, and employment gathered to discuss the following themes: the transition from initial training to employment…

Capabilities of radar as they might relate to entomological studies

NASA Technical Reports Server (NTRS)

Skolnik, M. I.

1979-01-01

A tutoral background of radar capabilities and its potential for insect research is provided. The basic principles and concepts of radar were reviewed. Information on current radar equipment was examined. Specific issues related to insect research included; target cross-section, radar frequency, tracking target recognition and false alarms, clutter reduction, radar transmitter power, and ascertained atmospheric processes.

Hierarchical Linear Modeling (HLM): An Introduction to Key Concepts within Cross-Sectional and Growth Modeling Frameworks. Technical Report #1308

ERIC Educational Resources Information Center

Anderson, Daniel

2012-01-01

This manuscript provides an overview of hierarchical linear modeling (HLM), as part of a series of papers covering topics relevant to consumers of educational research. HLM is tremendously flexible, allowing researchers to specify relations across multiple "levels" of the educational system (e.g., students, classrooms, schools, etc.).…

Perceptions of Present and Future Capability among a Sample of Rural British Columbia Youth Perceptions

ERIC Educational Resources Information Center

Kapil, Meg E.; Shepard, Blythe C.

2011-01-01

A cross-sectional survey explored 96 rural adolescents' perceptions of their rural context and how their self-concept is related to perceptions of capability regarding hopes and fears for the future. The youth surveyed, from the Kootenay Boundary region of British Columbia, indicated ambivalence about staying in their communities after leaving…

Pregnancy Intentions and Safer Pregnancy Knowledge Among Female Sex Workers in Port Elizabeth, South Africa.

PubMed

Rao, Amrita; Baral, Stefan; Phaswana-Mafuya, Nancy; Lambert, Andrew; Kose, Zamakayise; Mcingana, Mfezi; Holland, Claire; Ketende, Sosthenes; Schwartz, Sheree

2016-07-01

To assess the association between human immunodeficiency virus (HIV) and pregnancy intentions and safer conception knowledge among female sex workers in Port Elizabeth, South Africa. This cross-sectional study recruited female sex workers in Port Elizabeth using respondent-driven sampling and completed an interviewer-administered questionnaire alongside HIV testing and counseling. In this secondary analysis, robust Poisson regression was used to model prevalence ratios for positive fertility intentions in this cross-sectional study. Knowledge of safer conception methods by HIV status was compared using Fisher exact tests. Overall 391 women were represented in the analyses. More than 50% had a prior HIV diagnosis, and an additional 12% were diagnosed with HIV during the study. Approximately half (n=185) of the women reported future pregnancy intentions. In univariate analysis, a prior HIV diagnosis was negatively associated with pregnancy intentions as compared with HIV-negative women (prevalence ratio 0.68, 95% confidence interval 0.55-0.85). Only parity remained independently associated with future pregnancy intentions in multivariate regression after controlling for HIV status, age, race, relationship status, and years selling sex. Knowledge of safer conception methods such as timed sex without a condom, preexposure prophylaxis, or self-insemination was low and similar between those with and without future pregnancy plans. Pregnancy intentions did not significantly vary according to HIV status. Fertility intentions were high, however, and knowledge of safer conception methods low, suggesting a need to provide female sex workers with advice around options to conceive safely in the context of high HIV prevalence.

Illness self-concept in Type 1 diabetes: a cross-sectional view on clinical, demographic, and psychosocial correlates.

PubMed

Luyckx, Koen; Rassart, Jessica; Weets, Ilse

2015-01-01

The present study assessed the centrality of one's illness self-concept, or the degree to which chronic illness intrudes upon one's self, in a sample of 478 18-35-year-old patients with Type 1 diabetes. Confirmatory factor analysis indicated that illness self-concept centrality was a one-dimensional construct, despite the fact that three constituting components (i.e. pervasiveness, directionality, and illness self-consciousness) have been forwarded. Further, important demographic and clinical correlates of illness self-concept were identified: women, unemployed individuals, individuals with a lower educational level, and patients with an insulin pump had a more central illness self-concept. Finally, a series of correlation and regression analyses indicated that, despite the fact that illness self-concept centrality was negatively related to emotional stability, self-esteem, and diabetes integration, and positively to perceived consequences of diabetes, illness self-concept had unique predictive value over and above these variables for problem areas in diabetes and depressive symptoms. Implications and suggestions for future research are outlined.

Predicting sugar-sweetened behaviours with theory of planned behaviour constructs: Outcome and process results from the SIPsmartER behavioural intervention

PubMed Central

Zoellner, Jamie M.; Porter, Kathleen J.; Chen, Yvonnes; Hedrick, Valisa E.; You, Wen; Hickman, Maja; Estabrooks, Paul A.

2017-01-01

Objective Guided by the theory of planned behaviour (TPB) and health literacy concepts, SIPsmartER is a six-month multicomponent intervention effective at improving SSB behaviours. Using SIPsmartER data, this study explores prediction of SSB behavioural intention (BI) and behaviour from TPB constructs using: (1) cross-sectional and prospective models and (2) 11 single-item assessments from interactive voice response (IVR) technology. Design Quasi-experimental design, including pre- and post-outcome data and repeated-measures process data of 155 intervention participants. Main Outcome Measures Validated multi-item TPB measures, single-item TPB measures, and self-reported SSB behaviours. Hypothesised relationships were investigated using correlation and multiple regression models. Results TPB constructs explained 32% of the variance cross sectionally and 20% prospectively in BI; and explained 13–20% of variance cross sectionally and 6% prospectively. Single-item scale models were significant, yet explained less variance. All IVR models predicting BI (average 21%, range 6–38%) and behaviour (average 30%, range 6–55%) were significant. Conclusion Findings are interpreted in the context of other cross-sectional, prospective and experimental TPB health and dietary studies. Findings advance experimental application of the TPB, including understanding constructs at outcome and process time points and applying theory in all intervention development, implementation and evaluation phases. PMID:28165771

Agreement and disagreement on health care quality concepts among academic health professionals: the Saudi case.

PubMed

Mahrous, Mohamed Saad

2014-01-01

A systematic and rigorous implementation of quality improvement processes is likely to improve the well-being of staff members and heighten their job satisfaction. Assessing professionals' perceptions of health care quality should lead to the betterment of health care services. In Saudi Arabia, no previous studies examine how university health professionals view health care quality concepts. A cross-sectional analytical study employing a self-administered questionnaire with 43 statements assessing quality perceptions of academic health care professionals was used. Despite the agreement of health professionals on numerous quality concepts addressed in this study, there was insufficient agreement on 10 core quality concepts, 3 of which were the following: "quality focuses on customers" (50%), "quality is tangible and therefore measurable" (29.3%), and "quality is data-driven" (62%). Hence, providing health professionals with relevant training likely will generate a better understanding of quality concepts and optimize their performance.

Cross-sectional changes in lung volume measured by electrical impedance tomography are representative for the whole lung in ventilated preterm infants.

PubMed

van der Burg, Pauline S; Miedema, Martijn; de Jongh, Frans H; Frerichs, Inez; van Kaam, Anton H

2014-06-01

Electrical impedance tomography measures lung volume in a cross-sectional slice of the lung. Whether these cross-sectional volume changes are representative of the whole lung has only been investigated in adults, showing conflicting results. This study aimed to compare cross-sectional and whole lung volume changes using electrical impedance tomography and respiratory inductive plethysmography. A prospective, single-center, observational, nonrandomized study. The study was conducted in a neonatal ICU in the Netherlands. High-frequency ventilated preterm infants with respiratory distress syndrome. Cross-sectional and whole lung volume changes were continuously and simultaneously measured by, respectively, electrical impedance tomography and respiratory inductive plethysmography during a stepwise recruitment procedure. End-expiratory lung volume changes were assessed by mapping the inflation and deflation limbs using both the pressure/impedance and pressure/inductance pairs and characterized by calculating the inflection points. In addition, oscillatory tidal volume changes were assessed at each pressure step. Twenty-three infants were included in the study. Of these, eight infants had to be excluded because the quality of the registration was insufficient for analysis (two electrical impedance tomography and six respiratory inductive plethysmography). In the remaining 15 infants (gestational age 28.0 ± 2.6 wk; birth weight 1,027 ± 514 g), end-expiratory lung volume changes measured by electrical impedance tomography were significantly correlated to respiratory inductive plethysmography measurements in 12 patients (mean r = 0.93 ± 0.05). This was also true for the upper inflection point on the inflation (r = 0.91, p < 0.01) and deflation limb (r = 0.83, p < 0.01). In 13 patients, impedance and inductance data also correlated significantly on oscillatory tidal volume/pressure relationships (mean r = 0.81 ± 0.18). This study shows that cross-sectional lung volume changes measured by electrical impedance tomography are representative for the whole lung and that this concept also applies to newborn infants.

Electromagnetic fission of238U at 600 and 1000 MeV per nucleon

NASA Astrophysics Data System (ADS)

Rubehn, Th.; Müller, W. F. J.; Bassini, R.; Begemann-Blaich, M.; Blaich, Th.; Ferrero, A.; Groß, C.; Imme, G.; Iori, I.; Kunde, G. J.; Kunze, W. D.; Lindenstruth, V.; Lynen, U.; Möhlenkamp, T.; Moretto, L. G.; Ocker, B.; Pochodzalla, J.; Raciti, G.; Reito, S.; Sann, H.; Schüttauf, A.; Seidel, W.; Serfling, V.; Trautmann, W.; Trzcinski, A.; Verde, G.; Wörner, A.; Zude, E.; Zwieglinski, B.

1995-06-01

Electromagnetic fission of238U projectiles at E/A =600 and 1000 MeV was studied with the ALADIN spectrometer at the heavy-ion synchrotron SIS. Seven different targets (Be, C, Al, Cu, In, Au and U) were used. By considering only those fission events where the two charges added up to 92, most of the nuclear interactions were excluded. The nuclear contributions to the measured fission cross sections were determined by extrapolating from beryllium to the heavier targets with the concept of factorization. The obtained cross sections for electromagnetic fission are well reproduced by extended Weizsäcker-Williams calculations which include E1 and E2 excitations. The asymmetry of the fission fragments' charge distribution gives evidence for the excitation of the double giant-dipole resonance in uranium.

The concentration principle applied to spaceborne solar arrays. AGORA mission: Studies synthesis

NASA Astrophysics Data System (ADS)

Laget, R.

1986-01-01

Studies that led to selection of the distributed 25 kW SARA LOUVRE concept for the solar cell generator to be flown on the AGORA asteroid mission, and the major characteristics of such a spaceborne solar array are summarized. In the SARA LOUVRE concept, a parabolic cross section reflector concentrates incident light over the rear face of the identical, preceding reflector dish. The whole set of reflectors is pivotally commanded, thus compensating the effects of depointing. Geometric concentration factor is 10. End of life power level at 2.5 AU is 4.5 kW.

A Cross-Sectional Descriptive Study of Graduate Students' Perceptions of Learning Effectiveness in Face-to-Face and Online Courses

ERIC Educational Resources Information Center

Evans, Nicole Stayton

2013-01-01

The measurement of student perceptions of learning effectiveness is often used as a tool at universities to enhance the quality of course offerings. The recent growth in online course offerings creates new challenges in evaluating learning effectiveness. This study used three principles of adult learning theory, foundation, self-concept, and…

Diagrammatic exponentiation for products of Wilson lines

NASA Astrophysics Data System (ADS)

Mitov, Alexander; Sterman, George; Sung, Ilmo

2010-11-01

We provide a recursive diagrammatic prescription for the exponentiation of gauge theory amplitudes involving products of Wilson lines and loops. This construction generalizes the concept of webs, originally developed for eikonal form factors and cross sections with two eikonal lines, to general soft functions in QCD and related gauge theories. Our coordinate space arguments apply to arbitrary paths for the lines.

Effects of an Intervention on Children's Conceptions of Angle Measurement

ERIC Educational Resources Information Center

Culllen, Amanda L.; Cullen, Craig J.; O'Hanlon, Wendy A.

2018-01-01

In this article, we report on the findings of a study investigating the effects of an intervention designed to provide students in Grades 3-5 with opportunities to work with dynamic and static models of angles in a dynamic geometry environment. We utilized the microgenetic method in this cross-sectional study to observe and document changes in…

Heat pipes and their use in technology

NASA Technical Reports Server (NTRS)

Vasilyev, L.

1977-01-01

Heat pipes may be employed as temperature regulators, heat diodes, transformers, storage batteries, or utilized for transforming thermal energy into mechanical, electric, or other forms of energy. General concepts were established for the analysis of the transfer process in heat pipes. A system of equations was developed to describe the thermodynamics of steam passage through a cross section of a heat pipe.

Correlates of Quality of Life in New Migrants to Hong Kong from Mainland China

ERIC Educational Resources Information Center

Wong, Winky K. F.; Chou, Kee-Lee; Chow, Nelson W. S.

2012-01-01

The concept of Quality of life (QOL) has received considerable attention from different disciplines. The aim of this study was to identify what are the correlates of QOL among Chinese new immigrants in Hong Kong. Data were collected through a cross-sectional survey among 449 Hong Kong new immigrants from Mainland China. Bivariate and multiple…

The Public Library, Democracy and Rancière's Poetics of Politics

ERIC Educational Resources Information Center

Huzar, Timothy Jozef

2013-01-01

Introduction: This paper applies the thought of Jacques Rancière to the concept of democracy as it is traditionally understood in library studies literature. Methods: The paper reviews a cross-section of instances of the link between democracy and the public library in library studies literature. It offers a close textual analysis of Michael…

Exploring Chemistry Teacher Candidates' Profile Characteristics, Teaching Attitudes and Beliefs, and Chemistry Conceptions

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…

Virtopsy - the concept of a centralized database in forensic medicine for analysis and comparison of radiological and autopsy data.

PubMed

Aghayev, Emin; Staub, Lukas; Dirnhofer, Richard; Ambrose, Tony; Jackowski, Christian; Yen, Kathrin; Bolliger, Stephan; Christe, Andreas; Roeder, Christoph; Aebi, Max; Thali, Michael J

2008-04-01

Recent developments in clinical radiology have resulted in additional developments in the field of forensic radiology. After implementation of cross-sectional radiology and optical surface documentation in forensic medicine, difficulties in the validation and analysis of the acquired data was experienced. To address this problem and for the comparison of autopsy and radiological data a centralized database with internet technology for forensic cases was created. The main goals of the database are (1) creation of a digital and standardized documentation tool for forensic-radiological and pathological findings; (2) establishing a basis for validation of forensic cross-sectional radiology as a non-invasive examination method in forensic medicine that means comparing and evaluating the radiological and autopsy data and analyzing the accuracy of such data; and (3) providing a conduit for continuing research and education in forensic medicine. Considering the infrequent availability of CT or MRI for forensic institutions and the heterogeneous nature of case material in forensic medicine an evaluation of benefits and limitations of cross-sectional imaging concerning certain forensic features by a single institution may be of limited value. A centralized database permitting international forensic and cross disciplinary collaborations may provide important support for forensic-radiological casework and research.

Comparison of options for reduction of noise in the test section of the NASA Langley 4x7m wind tunnel, including reduction of nozzle area

NASA Technical Reports Server (NTRS)

Hayden, R. E.

1984-01-01

The acoustically significant features of the NASA 4X7m wind tunnel and the Dutch-German DNW low speed tunnel are compared to illustrate the reasons for large differences in background noise in the open jet test sections of the two tunnels. Also introduced is the concept of reducing test section noise levels through fan and turning vane source reductions which can be brought about by reducing the nozzle cross sectional area, and thus the circuit mass flow for a particular exit velocity. The costs and benefits of treating sources, paths, and changing nozzle geometry are reviewed.

Formulation and Analysis of the Quantum Radar Cross Section

NASA Astrophysics Data System (ADS)

Brandsema, Matthew J.

In radar, the amount of returns that an object sends back to the receiver after being struck by an electromagnetic wave is characterized by what is known as the radar cross section, denoted by sigma typically. There are many mechanisms that affect how much radiation is reflected back in the receiver direction, such as reflectivity, physical contours and dimensions, attenuation properties of the materials, projected cross sectional area and so on. All of these characteristics are lumped together in a single value of sigma, which has units of m2. Stealth aircrafts for example are designed to minimize its radar cross section and return the smallest amount of radiation possible in the receiver direction. A new concept has been introduced called quantum radar, that uses correlated quantum states of photons as well as the unique properties of quantum mechanics to ascertain information on a target at a distance. At the time of writing this dissertation, quantum radar is very much in its infancy. There still exist fundamental questions about the feasibility of its implementation, especially in the microwave spectrum. However, what has been theoretically determined, is that quantum radar has a fundamental advantage over classical radar in terms of resolution and returns in certain regimes. Analogous to the classical radar cross section (CRCS), the concept of the quantum radar cross section (QRCS) has been introduced. This quantity measures how an object looks to a quantum radar be describing how a single photon, or small cluster of photons scatter off of a macroscopic target. Preliminary simulations of the basic quantum radar cross section equation have yielded promising results showing an advantage in sidelobe response in comparison to the classical RCS. This document expands upon this idea by providing insight as to where this advantage originates, as well as developing more rigorous simulation analysis, and greatly expanding upon the theory. The expanded theory presented in this document includes re-deriving the QRCS formula to be a general bistatic formula, as the current equation is only valid for monostatic radar geometries. This re-derivation process also leads to the addition of terms that capture the effect of photon polarization, something that is not properly taken into account in the current literature. Most importantly, a new formulation of the QRCS formula will be derived that includes writing the equation in terms of Fourier transforms. This has a profound impact on the analysis of the theory of the QRCS as it allows for the derivation of closed form solutions of certain geometries, something that has never been possible due to the form of the current QRCS equation. All together, this document will provide a complete and general theory of the QRCS. After deriving the necessary equations, there will be extensive work in the utilization of these equations in deriving geometry dependent responses and comparing the closed form solutions to the classical solutions as well as comparing the solutions to the numerical simulations. The current literature relies exclusively on numerical simulations to analyze the behavior of the QRCS. The simulations done do not take into account the macroscopic nature of the target. Because the atoms are so numerous, and because of the underlying Fourier transform relationship, there are many issues of sampling that must be taken into account when performing simulations. Simulating an object with too few samples results in an aliased and incorrect version of the QRCS response. An extensive error analysis is presented which ensures an accurate simulation result based on sample number. Finally, possible future work endeavors will be presented which include QRCS diffraction, shadowing, more accurate simulation concepts, and the effect of quantum tunneling on the QRCS response.

Influence of perceived difficulty of cases on student osteopaths' diagnostic reasoning: a cross sectional study.

PubMed

Noyer, Aurelien L; Esteves, Jorge E; Thomson, Oliver P

2017-01-01

Diagnostic reasoning refers to the cognitive processes by which clinicians formulate diagnoses. Despite the implications for patient safety and professional identity, research on diagnostic reasoning in osteopathy remains largely theoretical. The aim of this study was to investigate the influence of perceived task difficulty on the diagnostic reasoning of students osteopaths. Using a single-blinded, cross sectional study design, sixteen final year pre-registration osteopathy students diagnosed two standardized cases under two context conditions (complex versus control). Context difficulty was manipulated via verbal manipulation and case order was randomized and counterbalanced across subjects to ensure that each case was diagnosed evenly under both conditions (i.e. half of the subjects performed either case A or B first). After diagnosis, participants were presented with items (literal, inferred and filler) designed to represent analytical and non-analytical reasoning. Response time and error rate for each item were measured. A repeated measures analysis of variance (concept type x context) was performed to identify differences across conditions and make inferences on diagnostic reasoning. Participants made significantly more errors when judging literal concepts and took significantly less time to recognize filler concepts in the complex context. No significant difference in ability to judge inferred concepts across contexts was found. Although speculative and preliminary, our findings suggest the perception of complexity led to an increased reliance on analytical reasoning at the detriment of non-analytical reasoning. To reduce the associated cognitive load, osteopathic educational institutions could consider developing the intuitive diagnostic capabilities of pre-registration students. Postgraduate mentorship opportunities could be considered to enhance the diagnostic reasoning of professional osteopaths, particularly recent graduates. Further research exploring the influence of expertise is required to enhance the validity of this study.

Design and analysis of variable-twist tiltrotor blades using shape memory alloy hybrid composites

NASA Astrophysics Data System (ADS)

Park, Jae-Sang; Kim, Seong-Hwan; Jung, Sung Nam; Lee, Myeong-Kyu

2011-01-01

The tiltrotor blade, or proprotor, acts as a rotor in the helicopter mode and as a propeller in the airplane mode. For a better performance, the proprotor should have different built-in twist distributions along the blade span, suitable for each operational mode. This paper proposes a new variable-twist proprotor concept that can adjust the built-in twist distribution for given flight modes. For a variable-twist control, the present proprotor adopts shape memory alloy hybrid composites (SMAHC) containing shape memory alloy (SMA) wires embedded in the composite matrix. The proprotor of the Korea Aerospace Research Institute (KARI) Smart Unmanned Aerial Vehicle (SUAV), which is based on the tiltrotor concept, is used as a baseline proprotor model. The cross-sectional properties of the variable-twist proprotor are designed to maintain the cross-sectional properties of the original proprotor as closely as possible. However, the torsion stiffness is significantly reduced to accommodate the variable-twist control. A nonlinear flexible multibody dynamic analysis is employed to investigate the dynamic characteristics of the proprotor such as natural frequency and damping in the whirl flutter mode, the blade structural loads in a transition flight and the rotor performance in hover. The numerical results show that the present proprotor is designed to have a strong similarity to the baseline proprotor in dynamic and load characteristics. It is demonstrated that the present proprotor concept could be used to improve the hover performance adaptively when the variable-twist control using the SMAHC is applied appropriately.

The Gap Concept as a Quality of Life Measure: Validation Study of the Child Quality of Life Systemic Inventory

ERIC Educational Resources Information Center

Etienne, Anne-Marie; Dupuis, Gilles; Spitz, Elisabeth; Lemetayer, Fabienne; Missotten, Pierre

2011-01-01

The objective was to determine the interest and psychometric properties of a new QOL self-assessment questionnaire suitable for children 8-12 years old measuring alpha, beta and gamma changes: the "Inventaire Systemique de Qualite de vie pour Enfants" (ISQV-E[C]). This was a cross-sectional validation study. 288 children have completed…

Holding Cargo in Place With Foam

NASA Technical Reports Server (NTRS)

Fisher, T. T.

1985-01-01

Foam fills entire container to protect cargo from shock and vibration. Originally developed for stowing space debris and spent satellites in Space Shuttle for return to Earth, encapsulation concept suitable for preparing shipments carried by truck, boat, or airplane. Equipment automatically injects polyurethane foam into its interior to hold cargo securely in place. Container of rectangular or other cross section built to match shape of vehicle used.

Cell inactivation, repair and mutation induction in bacteria after heavy ion exposure: results from experiments at accelerators and in space.

PubMed

Horneck, G; Schafer, M; Baltschukat, K; Weisbrod, U; Micke, U; Facius, R; Bucker, H

1989-01-01

To understand the mechanisms of accelerated heavy ions on biological matter, the responses of spores of B. subtilis to this structured high LET radiation was investigated applying two different approaches. 1) By the use of the Biostack concept, the inactivation probability as a function of radial distance to single particles' trajectory (i.e. impact parameter) was determined in space experiments as well as at accelerators using low fluences of heavy ions. It was found that spores can survive even a central hit and that the effective range of inactivation extends far beyond impact parameters where inactivation by delta-ray dose would be effective. Concerning the space experiment, the inactivation cross section exceeds those from comparable accelerator experiments by roughly a factor of 20. 2) From fluence effect curves, cross sections for inactivation and mutation induction, and the efficiency of repair processes were determined. They are influenced by the ions characteristics in a complex manner. According to dependence on LET, at least 3 LET ranges can be differentiated: A low LET range (app. < 200 keV/micrometers), where cross sections for inactivation and mutation induction follow a common curve for different ions and where repair processes are effective; an intermediate LET range of the so-called saturation cross section with negligible mutagenic and repair efficiency; and a high LET range (>1000 keV/micrometers) where the biological endpoints are majorly dependent on atomic mass and energy of the ion under consideration.

Middle cerebral artery diameter changes during rhythmic handgrip exercise in humans.

PubMed

Verbree, J; Bronzwaer, Agt; van Buchem, M A; Daemen, Mjap; van Lieshout, J J; van Osch, Mjp

2017-08-01

Transcranial Doppler (TCD) sonography is a frequently employed technique for quantifying cerebral blood flow by assuming a constant arterial diameter. Given that exercise increases arterial pressure by sympathetic activation, we hypothesized that exercise might induce a change in the diameter of large cerebral arteries. Middle cerebral artery (MCA) cross-sectional area was assessed in response to handgrip exercise by direct magnetic resonance imaging (MRI) observations. Twenty healthy subjects (11 female) performed three 5 min bouts of rhythmic handgrip exercise at 60% maximum voluntary contraction, alternated with 5 min of rest. High-resolution 7 T MRI scans were acquired perpendicular to the MCA. Two blinded observers manually determined the MCA cross-sectional area. Sufficient image quality was obtained in 101 MCA-scans of 19 subjects (age-range 20-59 years). Mixed effects modelling showed that the MCA cross-sectional area decreased by 2.1 ± 0.8% (p = 0.01) during handgrip, while the heart rate increased by 11 ± 2% (p < 0.001) at constant end-tidal CO 2 (p = 0.10). In conclusion, the present study showed a 2% decrease in MCA cross-sectional area during rhythmic handgrip exercise. This further strengthens the current concept of sympathetic control of large cerebral arteries, showing in vivo vasoconstriction during exercise-induced sympathetic activation. Moreover, care must be taken when interpreting TCD exercise studies as diameter constancy cannot be assumed.

The role of urgency in maladaptive behaviors.

PubMed

Anestis, Michael D; Selby, Edward A; Joiner, Thomas E

2007-12-01

Prior work on maladaptive behaviors has cited impulsivity as a risk factor. The concept of impulsivity, however, fails to address the potential role of negative affect in such behaviors. The UPPS Impulsive Behavior Scale addresses this weakness by dividing impulsivity into four subscales: Urgency, Sensation Seeking, (lack of) Premeditation, and (lack of) Perseverance. We predicted that urgency, defined as the tendency, specifically in the face of negative affect, to act quickly and without planning, would predict elevations on three maladaptive behaviors--excessive reassurance seeking, drinking to cope, and bulimic symptoms as measured by the Eating Disorder Inventory--in both cross-sectional and longitudinal analyses in an undergraduate sample (N=70). Participants were assessed at two time points, 3-4 weeks apart. Urgency significantly predicted all three outcome variables cross-sectionally at both Time 1 and Time 2. Time 1 urgency significantly predicted Time 2 excessive reassurance seeking. Changes in urgency from Time 1 to Time 2 predicted changes in all three outcome variables. Results indicate a clear cross-sectional relationship between urgency and certain maladaptive behaviors. Additionally, some form of longitudinal relationship may exist between these variables, although the use of residual change scores precluded distinction between true change and change due to error.

Carbon nanotube-based mode-locked wavelength-switchable fiber laser via net gain cross section alteration

NASA Astrophysics Data System (ADS)

Latif, A. A.; Mohamad, H.; Abu Bakar, M. H.; Muhammad, F. D.; Mahdi, M. A.

2016-02-01

We have proposed and demonstrated a carbon nanotube-based mode-locked erbium-doped fiber laser with switchable wavelength in the C-band wavelength region by varying the net gain cross section of erbium. The carbon nanotube is coated on a tapered fiber to form the saturable absorber for the purpose of mode-locking by exploiting the concept of evanescent field interaction on the tapered fiber with the carbon nanotube in a ring cavity configuration. The propagation loss is adjusted by inducing macrobend losses of the optical fiber in the cavity through a fiber spooling technique. Since the spooling radius can be gradually adjusted to achieve continuous tuning of attenuation, this passive tuning approach can be an alternative to optical tunable attenuator, with freedom of external device integration into the laser cavity. Based on this alteration, the net gain cross section of the laser system can be tailored to three different lasing wavelength ranges; 1533, 1560 nm and both (1533 and 1560 nm) with the minimum pulse duration of 734 fs. The proposed design is simple and stable with high beam quality and good reliability for multiple applications.

Static shape control for adaptive wings

NASA Astrophysics Data System (ADS)

Austin, Fred; Rossi, Michael J.; van Nostrand, William; Knowles, Gareth; Jameson, Antony

1994-09-01

A theoretical method was developed and experimentally validated, to control the static shape of flexible structures by employing internal translational actuators. A finite element model of the structure, without the actuators present, is employed to obtain the multiple-input, multiple-output control-system gain matrices for actuator-load control as well as actuator-displacement control. The method is applied to the quasistatic problem of maintaining an optimum-wing cross section during various transonic-cruise flight conditions to obtain significant reductions in the shock-induced drag. Only small, potentially achievable, adaptive modifications to the profile are required. The adaptive-wing concept employs actuators as truss elements of active ribs to reshape the wing cross section by deforming the structure. Finite element analyses of an adaptive-rib model verify the controlled-structure theory. Experiments on the model were conducted, and arbitrarily selected deformed shapes were accurately achieved.

A flexible telecom satellite repeater based on microwave photonic technologies

NASA Astrophysics Data System (ADS)

Sotom, Michel; Benazet, Benoît; Maignan, Michel

2017-11-01

Future telecom satellite based on geo-stationary Earth orbit (GEO) will require advanced payloads in Kaband so as to receive, route and re-transmit hundreds of microwave channels over multiple antenna beams. We report on the proof-of-concept demonstration of a analogue repeater making use of microwave photonic technologies for supporting broadband, transparent, and flexible cross-connectivity. It has microwave input and output sections, and features a photonic core for LO distribution, frequency down-conversion, and cross-connection of RF channels. With benefits such as transparency to RF frequency, infinite RF isolation, mass and volume savings, such a microwave photonic cross-connect would compare favourably with microwave implementations, and based on optical MEMS switches could grow up to large port counts.

Factors relating to professional self-concept among nurse managers.

PubMed

Kantek, Filiz; Şimşek, Belkıs

2017-12-01

To investigate the self-concept in nurse managers in Turkey and the effects of certain variables on professional self-concept. Professional self-concept plays a significant role in improving certain professional behaviours. Nursing managers have the potential to influence other members of the profession with their attitudes and behaviours. The study was designed as a cross-sectional descriptive study. This study was conducted with 159 nurse managers in nine different hospitals. The study data were collected with a Personal Information Form and Professional Self-concept Nursing Inventory, and the data analysis was accomplished with descriptive statistics, Cronbach's alpha coefficients and Chi-squared Automatic Interaction Detector analyses. The professional self-concept score of nurse managers was 3·33 (SD = 0·308). Professional competence subdimension had the highest scores, while professional satisfaction subdimension had the lowest. The types of hospital were found to be influential on professional self-concept. The types of hospital were reported to influence the professional self-concept of nurses. Nursing managers are visionaries who can potentially influence nursing practices and decisions. Nursing leaders must monitor and administer strategies to improve their professional self-concept. © 2017 John Wiley & Sons Ltd.

Supersonic aerodynamic characteristics of some reentry concepts for angles of attack up to 90 deg

NASA Technical Reports Server (NTRS)

Spearman, M. L.

1985-01-01

Past studies of reentry vehicles tested to high angles of attack (up to 90 deg) in the Mach number range from 2 to 4.8 have provided some fundamental insights into the aerodynamic characteristics of such vehicles. Two basic planforms are considered in this paper: highly swept deltas, and circular. The delta concepts include variations in cross section (and thus volume) and in camber distribution. The effectiveness of various types of aerodynamic control devices is also included. The purpose of the paper is to examine the characteristics of the vehicles with a view toward the potential usefulness of such concepts in a flight regime that would include reentry from space into the atmosphere, followed by a transition to sustained atmospheric flight.

On the attenuation of sound by three-dimensionally segmented acoustic liners in a rectangular duct

NASA Technical Reports Server (NTRS)

Koch, W.

1979-01-01

Axial segmentation of acoustically absorbing liners in rectangular, circular or annual duct configurations is a very useful concept for obtaining higher noise attenuation with respect to the bandwidth of absorption as well as the maximum attenuation. As a consequence, advanced liner concepts are proposed which induce a modal energy transfer in both cross-sectional directions to further reduce the noise radiated from turbofan engines. However, these advanced liner concepts require three-dimensional geometries which are difficult to treat theoretically. A very simple three-dimensional problem is investigated analytically. The results show a strong dependence on the positioning of the liner for some incident source modes while the effect of three-dimensional segmentation appears to be negligible over the frequency range considered.

Lunar surface structural concepts and construction studies

NASA Technical Reports Server (NTRS)

Mikulas, Martin

1991-01-01

The topics are presented in viewgraph form and include the following: lunar surface structures construction research areas; lunar crane related disciplines; shortcomings of typical mobile crane in lunar base applications; candidate crane cable suspension systems; NIST six-cable suspension crane; numerical example of natural frequency; the incorporation of two new features for improved performance of the counter-balanced actively-controlled lunar crane; lunar crane pendulum mechanics; simulation results; 1/6 scale lunar crane testbed using GE robot for global manipulation; basic deployable truss approaches; bi-pantograph elevator platform; comparison of elevator platforms; perspective of bi-pantograph beam; bi-pantograph synchronously deployable tower/beam; lunar module off-loading concept; module off-loader concept packaged; starburst deployable precision reflector; 3-ring reflector deployment scheme; cross-section of packaged starburst reflector; and focal point and thickness packaging considerations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walters, C.T.; Dulaney, J.L.; Campbell, B.E.

Demonstrations of operation of a compact neodymium glass laser with average output powers greater than 1 kW for several seconds are reported. The laser is based on the thermal inertia laser (TIL) concept wherein a neodymium-doped glass rod is pumped uniformly without cooling during a burst mode of laser operation. Design principles for TIL devices and scaling to 100 kW class lasers are discussed. Experimental results for a low repetition-rate proof-of-concept pulsed device (30 J, 0.2 Hz) and a high repetition-rate pulsed prototype (40 J, 36 Hz) are presented and compared to numerical solutions for the laser rate equations withmore » temperature dependent cross-sections.« less

Quantitative research.

PubMed

Watson, Roger

2015-04-01

This article describes the basic tenets of quantitative research. The concepts of dependent and independent variables are addressed and the concept of measurement and its associated issues, such as error, reliability and validity, are explored. Experiments and surveys – the principal research designs in quantitative research – are described and key features explained. The importance of the double-blind randomised controlled trial is emphasised, alongside the importance of longitudinal surveys, as opposed to cross-sectional surveys. Essential features of data storage are covered, with an emphasis on safe, anonymous storage. Finally, the article explores the analysis of quantitative data, considering what may be analysed and the main uses of statistics in analysis.

Logic and memory concepts for all-magnetic computing based on transverse domain walls

NASA Astrophysics Data System (ADS)

Vandermeulen, J.; Van de Wiele, B.; Dupré, L.; Van Waeyenberge, B.

2015-06-01

We introduce a non-volatile digital logic and memory concept in which the binary data is stored in the transverse magnetic domain walls present in in-plane magnetized nanowires with sufficiently small cross sectional dimensions. We assign the digital bit to the two possible orientations of the transverse domain wall. Numerical proofs-of-concept are presented for a NOT-, AND- and OR-gate, a FAN-out as well as a reading and writing device. Contrary to the chirality based vortex domain wall logic gates introduced in Omari and Hayward (2014 Phys. Rev. Appl. 2 044001), the presented concepts remain applicable when miniaturized and are driven by electrical currents, making the technology compatible with the in-plane racetrack memory concept. The individual devices can be easily combined to logic networks working with clock speeds that scale linearly with decreasing design dimensions. This opens opportunities to an all-magnetic computing technology where the digital data is stored and processed under the same magnetic representation.

The initial treatment of the concept of function in the selected secondary school mathematics textbooks in the US and China

NASA Astrophysics Data System (ADS)

Son, Ji-Won; Hu, Qintong

2016-05-01

In order to provide insight into cross-national differences in students' achievement, this study compares the initial treatment of the concept of function sections of Chinese and US textbooks. The number of lessons, contents, and mathematical problems were analyzed. The results show that the US curricula introduce the concept of function one year earlier than the Chinese curriculum and provide strikingly more problems for students to work on. However, the Chinese curriculum emphasizes developing both concepts and procedures and includes more problems that require explanations, visual representations, and problem solving in worked-out examples that may help students formulate multiple solution methods. This result could indicate that instead of the number of problems and early introduction of the concept, the cognitive demands of textbook problems required for student thinking could be one reason for differences in American and Chinese students' performances in international comparative studies. Implications of these findings for curriculum developers, teachers, and researchers are discussed.

Controlling Sample Rotation in Acoustic Levitation

NASA Technical Reports Server (NTRS)

Barmatz, M. B.; Stoneburner, J. D.

1985-01-01

Rotation of acoustically levitated object stopped or controlled according to phase-shift monitoring and control concept. Principle applies to square-cross-section levitation chamber with two perpendicular acoustic drivers operating at same frequency. Phase difference between X and Y acoustic excitation measured at one corner by measuring variation of acoustic amplitude sensed by microphone. Phase of driver adjusted to value that produces no rotation or controlled rotation of levitated object.

Investigation of Truncated Waveguides

NASA Technical Reports Server (NTRS)

Lourie, Nathan P.; Chuss, David T.; Henry, Ross M.; Wollack, Edward J.

2013-01-01

The design, fabrication, and performance of truncated circular and square waveguide cross-sections are presented. An emphasis is placed upon numerical and experimental validation of simple analytical formulae that describe the propagation properties of these structures. A test component, a 90-degree phase shifter, was fabricated and tested at 30 GHz. The concepts explored can be directly applied in the design, synthesis and optimization of components in the microwave to sub-millimeter wavebands.

Media Exposure in Very Young Girls: Prospective and Cross-Sectional Relationships with BMIz, Self-Esteem and Body Size Stereotypes

ERIC Educational Resources Information Center

Rodgers, Rachel F.; Damiano, Stephanie R.; Wertheim, Eleanor H.; Paxton, Susan J.

2017-01-01

Media exposure among young children has been suggested to influence self-concept and the adoption of social stereotypes regarding body weight, as well as being associated with increased weight. The aim of this study was to examine the role of TV/DVD viewing in the development of positive stereotypes toward thinness, self-esteem and body mass index…

Social responsibility of the hospitals in Isfahan city, Iran: Results from a cross-sectional survey

PubMed Central

Keyvanara, Mahmoud; Sajadi, Haniye Sadat

2015-01-01

Background: Changes in modern societies develop the perception that the external environment is essential in organization’s practices, especially in the way they deal with aspects such as human rights, community needs, market demands and environmental interests. These issues are usually under the umbrella of the concept of social responsibility. Given the importance of this concept in the context of health care delivery, suggesting a new paradigm in hospital governance, the aim of this study was to measure the social responsibility in hospitals. Methods: A cross-sectional survey was employed to collect data from a sample of 946 hospital staff of Isfahan city. Data was obtained by structured and valid self-administrated questionnaire and analyzed by descriptive and analytic statistics using SPSS. Results: The mean score of hospitals’ social responsibility was 3.0 compared with the justified range from 1.0 to 5.0. Results showed that there was a significant relationship between social responsibility score and hospitals’ ownership (public or private). Also, there was no significant relationship between social responsibility and type of hospital specialty. Conclusion: It is recommended that hospital managers develop and apply appropriate policies and strategies to improve their hospitals’ social responsibility level, especially through concentrating on their staff’s working environment. PMID:26340391

Social responsibility of the hospitals in Isfahan city, Iran: Results from a cross-sectional survey.

PubMed

Keyvanara, Mahmoud; Sajadi, Haniye Sadat

2015-02-12

Changes in modern societies develop the perception that the external environment is essential in organization's practices, especially in the way they deal with aspects such as human rights, community needs, market demands and environmental interests. These issues are usually under the umbrella of the concept of social responsibility. Given the importance of this concept in the context of health care delivery, suggesting a new paradigm in hospital governance, the aim of this study was to measure the social responsibility in hospitals. A cross-sectional survey was employed to collect data from a sample of 946 hospital staff of Isfahan city. Data was obtained by structured and valid self-administrated questionnaire and analyzed by descriptive and analytic statistics using SPSS. The mean score of hospitals' social responsibility was 3.0 compared with the justified range from 1.0 to 5.0. Results showed that there was a significant relationship between social responsibility score and hospitals' ownership (public or private). Also, there was no significant relationship between social responsibility and type of hospital specialty. It is recommended that hospital managers develop and apply appropriate policies and strategies to improve their hospitals' social responsibility level, especially through concentrating on their staff's working environment. © 2015 by Kerman University of Medical Sciences.

Teachers and Coaches in Adolescent Social Networks Are Associated With Healthier Self-Concept and Decreased Substance Use

PubMed Central

Dudovitz, Rebecca N.; Chung, Paul J.; Wong, Mitchell D.

2017-01-01

Background Poor academic (eg, “I am a bad student”) and behavioral (eg, “I am a troublemaker”) self-concepts are strongly linked to adolescent substance use. Social networks likely influence self-concept. However, little is understood about the role teachers and athletic coaches play in shaping both academic and behavioral self-concepts. Methods We analyzed cross-sectional surveys of 929 9th-12th grade low-income minority adolescents in Los Angeles assessing self-concept, social networks, and 30-day use of alcohol, marijuana and other drugs. We performed generalized estimating equations, accounting for clustering at the school level and controlling for family and peer influences and contextual factors. We also tested whether self-concept-mediated associations between relationships with teachers or coaches and 30-day substance use. Results More perceived teacher support was associated with lower odds of marijuana and other drug use and better academic and behavioral self-concepts. Behavioral self-concept mediated the associations between teacher support and substance use. Conclusions By facilitating relationships with adults and improving teachers' capacity to build supportive environments, schools may positively shape how adolescents see themselves, which might help reduce adolescent substance use. PMID:27917487

Teachers and Coaches in Adolescent Social Networks Are Associated With Healthier Self-Concept and Decreased Substance Use.

PubMed

Dudovitz, Rebecca N; Chung, Paul J; Wong, Mitchell D

2017-01-01

Poor academic (eg, "I am a bad student") and behavioral (eg, "I am a troublemaker") self-concepts are strongly linked to adolescent substance use. Social networks likely influence self-concept. However, little is understood about the role teachers and athletic coaches play in shaping both academic and behavioral self-concepts. We analyzed cross-sectional surveys of 929 9th-12th grade low-income minority adolescents in Los Angeles assessing self-concept, social networks, and 30-day use of alcohol, marijuana and other drugs. We performed generalized estimating equations, accounting for clustering at the school level and controlling for family and peer influences and contextual factors. We also tested whether self-concept-mediated associations between relationships with teachers or coaches and 30-day substance use. More perceived teacher support was associated with lower odds of marijuana and other drug use and better academic and behavioral self-concepts. Behavioral self-concept mediated the associations between teacher support and substance use. By facilitating relationships with adults and improving teachers' capacity to build supportive environments, schools may positively shape how adolescents see themselves, which might help reduce adolescent substance use. © 2016, American School Health Association.

Evaluation of Impinging Stream Vortex Chamber Concepts for Liquid Rocket Engine Applications

NASA Technical Reports Server (NTRS)

Trinh, Huu; Kopicz, Charles; Bullard, Brad; Michaels, Scott

2003-01-01

NASA Marshall Space Flight Center (MSFC) and the U. S. Army are jointly investigating vortex chamber concepts for cryogenic oxygen/hydrocarbon fuel rocket engine applications. One concept, the Impinging Stream Vortex Chamber Concept (ISVC), has been tested with gel propellants at AMCOM at Redstone Arsenal, Alabama. A version of this concept for the liquid oxygen (LOX)/hydrocarbon fuel (RP-1) propellant system is derived from the one for the gel propellant. An unlike impinging injector is employed to deliver the propellants to the chamber. MSFC has also designed two alternative injection schemes, called the chasing injectors, associated with this vortex chamber concept. In these injection techniques, both propellant jets and their impingement point are in the same chamber cross-sectional plane. One injector has a similar orifice size with the original unlike impinging injector. The second chasing injector has small injection orifices. The team has achieved their objectives of demonstrating the self-cooled chamber wall benefits of ISVC and of providing the test data for validating computational fluids dynamics (CFD) models. These models, in turn, will be used to design the optimum vortex chambers in the future.

Physics Structure Analysis of Parallel Waves Concept of Physics Teacher Candidate

NASA Astrophysics Data System (ADS)

Sarwi, S.; Supardi, K. I.; Linuwih, S.

2017-04-01

The aim of this research was to find a parallel structure concept of wave physics and the factors that influence on the formation of parallel conceptions of physics teacher candidates. The method used qualitative research which types of cross-sectional design. These subjects were five of the third semester of basic physics and six of the fifth semester of wave course students. Data collection techniques used think aloud and written tests. Quantitative data were analysed with descriptive technique-percentage. The data analysis technique for belief and be aware of answers uses an explanatory analysis. Results of the research include: 1) the structure of the concept can be displayed through the illustration of a map containing the theoretical core, supplements the theory and phenomena that occur daily; 2) the trend of parallel conception of wave physics have been identified on the stationary waves, resonance of the sound and the propagation of transverse electromagnetic waves; 3) the influence on the parallel conception that reading textbooks less comprehensive and knowledge is partial understanding as forming the structure of the theory.

Quality of life after percutaneous coronary intervention: part 1.

PubMed

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.

Using Cross-Sectional Imaging to Convey Organ Relationships: An Integrated Learning Environment for Students of Gross Anatomy

PubMed Central

Forman, Bruce H.; Eccles, Randy; Piggins, Judith; Raila, Wayne; Estey, Greg; Barnett, G. Octo

1990-01-01

We have developed a visually oriented, computer-controlled learning environment designed for use by students of gross anatomy. The goals of this module are to reinforce the concepts of organ relationships and topography by using computed axial tomographic (CAT) images accessed from a videodisc integrated with color graphics and to introduce students to cross-sectional radiographic anatomy. We chose to build the program around CAT scan images because they not only provide excellent structural detail but also offer an anatomic orientation (transverse) that complements that used in the dissection laboratory (basically a layer-by-layer, anterior-to-posterior, or coronal approach). Our system, built using a Microsoft Windows-386 based authoring environment which we designed and implemented, integrates text, video images, and graphics into a single screen display. The program allows both user browsing of information, facilitated by hypertext links, and didactic sessions including mini-quizzes for self-assessment.

Measuring Knowledge Integration Learning of Energy Topics: A two-year longitudinal study

NASA Astrophysics Data System (ADS)

Liu, Ou Lydia; Ryoo, Kihyun; Linn, Marcia C.; Sato, Elissa; Svihla, Vanessa

2015-05-01

Although researchers call for inquiry learning in science, science assessments rarely capture the impact of inquiry instruction. This paper reports on the development and validation of assessments designed to measure middle-school students' progress in gaining integrated understanding of energy while studying an inquiry-oriented curriculum. The assessment development was guided by the knowledge integration framework. Over 2 years of implementation, more than 4,000 students from 4 schools participated in the study, including a cross-sectional and a longitudinal cohort. Results from item response modeling analyses revealed that: (a) the assessments demonstrated satisfactory psychometric properties in terms of reliability and validity; (b) both the cross-sectional and longitudinal cohorts made progress on integrating their understanding energy concepts; and (c) among many factors (e.g. gender, grade, school, and home language) associated with students' science performance, unit implementation was the strongest predictor.

Comparison and experimental validation of two potential resonant viscosity sensors in the kilohertz range

NASA Astrophysics Data System (ADS)

Lemaire, Etienne; Heinisch, Martin; Caillard, Benjamin; Jakoby, Bernhard; Dufour, Isabelle

2013-08-01

Oscillating microstructures are well established and find application in many fields. These include force sensors, e.g. AFM micro-cantilevers or accelerometers based on resonant suspended plates. This contribution presents two vibrating mechanical structures acting as force sensors in liquid media in order to measure hydrodynamic interactions. Rectangular cross section microcantilevers as well as circular cross section wires are investigated. Each structure features specific benefits, which are discussed in detail. Furthermore, their mechanical parameters and their deflection in liquids are characterized. Finally, an inverse analytical model is applied to calculate the complex viscosity near the resonant frequency for both types of structures. With this approach it is possible to determine rheological parameters in the kilohertz range in situ within a few seconds. The monitoring of the complex viscosity of yogurt during the fermentation process is used as a proof of concept to qualify at least one of the two sensors in opaque mixtures.

Seventh Graders' Academic Achievement, Creativity, and Ability to Construct a Cross-Domain Concept Map--A Brain Function Perspective

ERIC Educational Resources Information Center

Yeh, Yu-Chu

2004-01-01

This study proposes an interactive model of "cross-domain" concept mapping with an emphasis on brain functions, and it further investigates the relationships between academic achievement, creative thinking, and cross-domain concept mapping. Sixty-nine seventh graders participated in this study which employed two 50-minute instructional…

Planar spatial correlations, anisotropy, and specific surface area of stationary random porous media

NASA Astrophysics Data System (ADS)

Berryman, James G.

1998-02-01

An earlier result of the author showed that an anisotropic spatial correlation function of a random porous medium could be used to compute the specific surface area when it is stationary as well as anisotropic by first performing a three-dimensional radial average and then taking the first derivative with respect to lag at the origin. This result generalized the earlier result for isotropic porous media of Debye et al. [J. Appl. Phys. 28, 679 (1957)]. The present article provides more detailed information about the use of spatial correlation functions for anisotropic porous media and in particular shows that, for stationary anisotropic media, the specific surface area can be related to the derivative of the two-dimensional radial average of the correlation function measured from cross sections taken through the anisotropic medium. The main concept is first illustrated using a simple pedagogical example for an anisotropic distribution of spherical voids. Then, a general derivation of formulas relating the derivative of the planar correlation functions to surface integrals is presented. When the surface normal is uniformly distributed (as is the case for any distribution of spherical voids), our formulas can be used to relate a specific surface area to easily measurable quantities from any single cross section. When the surface normal is not distributed uniformly (as would be the case for an oriented distribution of ellipsoidal voids), our results show how to obtain valid estimates of specific surface area by averaging measurements on three orthogonal cross sections. One important general observation for porous media is that the surface area from nearly flat cracks may be underestimated from measurements on orthogonal cross sections if any of the cross sections happen to lie in the plane of the cracks. This result is illustrated by taking the very small aspect ratio (penny-shaped crack) limit of an oblate spheroid, but holds for other types of flat surfaces as well.

Load-based approaches for modelling visual clarity in streams at regional scale.

PubMed

Elliott, A H; Davies-Colley, R J; Parshotam, A; Ballantine, D

2013-01-01

Reduction of visual clarity in streams by diffuse sources of fine sediment is a cause of water quality impairment in New Zealand and internationally. In this paper we introduce the concept of a load of optical cross section (LOCS), which can be used for load-based management of light-attenuating substances and for water quality models that are based on mass accounting. In this approach, the beam attenuation coefficient (units of m(-1)) is estimated from the inverse of the visual clarity (units of m) measured with a black disc. This beam attenuation coefficient can also be considered as an optical cross section (OCS) per volume of water, analogous to a concentration. The instantaneous 'flux' of cross section is obtained from the attenuation coefficient multiplied by the water discharge, and this can be accumulated over time to give an accumulated 'load' of cross section (LOCS). Moreover, OCS is a conservative quantity, in the sense that the OCS of two combined water volumes is the sum of the OCS of the individual water volumes (barring effects such as coagulation, settling, or sorption). The LOCS can be calculated for a water quality station using rating curve methods applied to measured time series of visual clarity and flow. This approach was applied to the sites in New Zealand's National Rivers Water Quality Network (NRWQN). Although the attenuation coefficient follows roughly a power relation with flow at some sites, more flexible loess rating curves are required at other sites. The hybrid mechanistic-statistical catchment model SPARROW (SPAtially Referenced Regressions On Watershed attributes), which is based on a mass balance for mean annual load, was then applied to the NRWQN dataset. Preliminary results from this model are presented, highlighting the importance of factors related to erosion, such as rainfall, slope, hardness of catchment rock types, and the influence of pastoral development on the load of optical cross section.

Planar spatial correlations, anisotropy, and specific surface area of stationary random porous media

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berryman, J.G.

1998-02-01

An earlier result of the author showed that an anisotropic spatial correlation function of a random porous medium could be used to compute the specific surface area when it is stationary as well as anisotropic by first performing a three-dimensional radial average and then taking the first derivative with respect to lag at the origin. This result generalized the earlier result for isotropic porous media of Debye {ital et al.} [J. Appl. Phys. {bold 28}, 679 (1957)]. The present article provides more detailed information about the use of spatial correlation functions for anisotropic porous media and in particular shows that,more » for stationary anisotropic media, the specific surface area can be related to the derivative of the two-dimensional radial average of the correlation function measured from cross sections taken through the anisotropic medium. The main concept is first illustrated using a simple pedagogical example for an anisotropic distribution of spherical voids. Then, a general derivation of formulas relating the derivative of the planar correlation functions to surface integrals is presented. When the surface normal is uniformly distributed (as is the case for any distribution of spherical voids), our formulas can be used to relate a specific surface area to easily measurable quantities from any single cross section. When the surface normal is not distributed uniformly (as would be the case for an oriented distribution of ellipsoidal voids), our results show how to obtain valid estimates of specific surface area by averaging measurements on three orthogonal cross sections. One important general observation for porous media is that the surface area from nearly flat cracks may be underestimated from measurements on orthogonal cross sections if any of the cross sections happen to lie in the plane of the cracks. This result is illustrated by taking the very small aspect ratio (penny-shaped crack) limit of an oblate spheroid, but holds for other types of flat surfaces as well.« less

Self-Concept and Self-Esteem: A Cross-Cultural Perspective.

ERIC Educational Resources Information Center

Wood, Melinda

1991-01-01

Describes issues of self-concept and self-esteem that arise when people find themselves living in a cross-cultural environment. Discusses Western definition of self-concept and other self-concept models. Discusses self-esteem and integration and adjustment as it relates to bicultural persons. (ABL)

Differential compaction influences on structure in West Cameron Block 225 field

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finley, W.R.

The concept to be illustrated here is the influence on structural configuration of differential compaction caused by lateral variations in stratigraphy, specifically, changes from sand to shale within the same stratigraphic interval, The example chosen to illustrate this concept is West Cameron Block 225 field. As seen in structural stratigraphic cross sections as well as net sand maps constructed in the example field, several channel sands are seen to strongly influence the structural configuration. The basic structure within the field as defined by well and seismic data consists of a gentle, southerly dipping, north south-oriented ridge, bounded by a down-to-the-eastmore » fault on the west flank and a down-to-the-south fault to the north. Gentle roll into these faults closes the north flank of the structure. The stratigraphic section consists of alternating sands and shales of Miocene and Pliocene age. Several of these sands map out as linear sand bodies interpreted to be channels. These channels, representing thickened sand bodies that grade laterally into predominantly shale facies, are oriented in a general east-west direction. The juxtaposition of the basic structural orientation with the orientation of the channel sand(s) sets up a crossing point(s) on the southern flank of the structure. With the advent of differential compaction between the channel sands and the bounding shale faces, a stratigraphic structure is generated. This resulting compaction structure maps out as a double-lobed or saddled high. This effect is amplified as channels in the shallower section stack out over the southern flank of the structure until the southern crest dominates over the northern one. The overall result is one of migrating structural crests caused by variations in compactibility within the stratigraphic section.« less

GSTARS computer models and their applications, part I: theoretical development

USGS Publications Warehouse

Yang, C.T.; Simoes, F.J.M.

2008-01-01

GSTARS is a series of computer models developed by the U.S. Bureau of Reclamation for alluvial river and reservoir sedimentation studies while the authors were employed by that agency. The first version of GSTARS was released in 1986 using Fortran IV for mainframe computers. GSTARS 2.0 was released in 1998 for personal computer application with most of the code in the original GSTARS revised, improved, and expanded using Fortran IV/77. GSTARS 2.1 is an improved and revised GSTARS 2.0 with graphical user interface. The unique features of all GSTARS models are the conjunctive use of the stream tube concept and of the minimum stream power theory. The application of minimum stream power theory allows the determination of optimum channel geometry with variable channel width and cross-sectional shape. The use of the stream tube concept enables the simulation of river hydraulics using one-dimensional numerical solutions to obtain a semi-two- dimensional presentation of the hydraulic conditions along and across an alluvial channel. According to the stream tube concept, no water or sediment particles can cross the walls of stream tubes, which is valid for many natural rivers. At and near sharp bends, however, sediment particles may cross the boundaries of stream tubes. GSTARS3, based on FORTRAN 90/95, addresses this phenomenon and further expands the capabilities of GSTARS 2.1 for cohesive and non-cohesive sediment transport in rivers and reservoirs. This paper presents the concepts, methods, and techniques used to develop the GSTARS series of computer models, especially GSTARS3. ?? 2008 International Research and Training Centre on Erosion and Sedimentation and the World Association for Sedimentation and Erosion Research.

Representation of Nursing Terminologies in UMLS

PubMed Central

Kim, Tae Youn; Coenen, Amy; Hardiker, Nicholas; Bartz, Claudia C.

2011-01-01

There are seven nursing terminologies or classifications that are considered a standard to support nursing practice in the U.S. Harmonizing these terminologies will enhance the interoperability of clinical data documented across nursing practice. As a first step to harmonize the nursing terminologies, the purpose of this study was to examine how nursing problems or diagnostic concepts from select terminologies were cross-mapped in Unified Medical Language System (UMLS). A comparison analysis was conducted by examining whether cross-mappings available in UMLS through concept unique identifiers were consistent with cross-mappings conducted by human experts. Of 423 concepts from three terminologies, 411 (97%) were manually cross-mapped by experts to the International Classification for Nursing Practice. The UMLS semantic mapping among the 411 nursing concepts presented 33.6% accuracy (i.e., 138 of 411 concepts) when compared to expert cross-mappings. Further research and collaboration among experts in this field are needed for future enhancement of UMLS. PMID:22195127

The associations between perceived distributive, procedural, and interactional organizational justice, self-rated health and burnout.

PubMed

Liljegren, Mats; Ekberg, Kerstin

2009-01-01

The aim of the present study was to examine the cross-sectional and 2-year longitudinal associations between perceived organizational justice, self-rated health and burnout. The study used questionnaire data from 428 Swedish employment officers and the data was analyzed with Structural Equation Modeling, SEM. Two different models were tested: a global organizational justice model (with and without correlated measurement errors) and a differentiated (distributive, procedural and interactional organizational justice) justice model (with and without correlated measurement errors). The global justice model with autocorrelations had the most satisfactory goodness-of-fit indices. Global justice showed statistically significant (p < 0.01) cross-sectional (0.80 {mle 0.84) and longitudinal positive associations (0.76 mle 0.82) between organizational justice and self-rated health, and significant (p < 0.01) negative associations between organizational justice and burnout (cross-sectional: mle = -0.85, longitudinal -0.83 mle -0.84). The global justice construct showed better goodness-of-fit indices than the threefold justice construct but a differentiated organizational justice concept could give valuable information about health related risk factors: if they are structural (distributive justice), procedural (procedural justice) or inter-personal (interactional justice). The two approaches to study organizational justice should therefore be regarded as complementary rather than exclusive.

Measurement and analysis of aircraft and vehicle LRCS in outfield test

NASA Astrophysics Data System (ADS)

Cao, Chang-Qing; Zeng, Xiao-dong; Fan, Zhao-jin; Feng, Zhe-jun; Lai, Zhi

2015-04-01

The measurement of aircraft and vehicle Laser Radar Cross Section (LRCS) is of crucial importance for the detection system evaluation and the characteristic research of the laser scattering. A brief introduction of the measuring theory of the laser scattering from the full-scale aircraft and vehicle targets is presented in this paper. By analyzing the measuring condition in outfield test, the laser systems and test steps are designed for full-scale aircraft and vehicle LRCS and verified by the experiment in laboratory. The processing data error 7% below is obtained of the laser radar cross section by using Gaussian compensation and elimination of sky background for original test data. The study of measurement and analysis proves that the proposed method is effective and correct to get laser radar cross section data in outfield test. The objectives of this study were: (1) to develop structural concepts for different LRCS fuselage configurations constructed of conventional materials; (2) to compare these findings with those of aircrafts or vehicles; (3) to assess the application of advanced materials for each configuration; (4) to conduct an analytical investigation of the aerodynamic loads, vertical drag and mission performance of different LRCS configurations; and (5) to compare these findings with those of the aircrafts or vehicles.

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.

Probing Subdiffraction Limit Separations with Plasmon Coupling Microscopy: Concepts and Applications

PubMed Central

Wu, Linxi

2014-01-01

Due to their advantageous materials properties, noble metal nanoparticles are versatile tools in biosensing and imaging. A characteristic feature of gold and silver nanoparticles is their ability to sustain localized surface plasmons that provide both large optical cross-sections and extraordinary photophysical stability. Plasmon Coupling Microscopy takes advantage of the beneficial optical properties and utilizes electromagnetic near-field coupling between individual noble metal nanoparticle labels to resolve subdiffraction limit separations in an all-optical fashion. This Tutorial provides an introduction into the physical concepts underlying distance dependent plasmon coupling, discusses potential experimental implementations of Plasmon Coupling Microscopy, and reviews applications in the area of biosensing and imaging. PMID:24390574

Mechanisms underlying comprehension of health information in adulthood: the roles of prior knowledge and working memory capacity.

PubMed

Soederberg Miller, Lisa M; Gibson, Tanja N; Applegate, Elizabeth A; de Dios, Jeannette

2011-07-01

Prior knowledge, working memory capacity (WMC), and conceptual integration (attention allocated to integrating concepts in text) are critical within many contexts; however, their impact on the acquisition of health information (i.e. learning) is relatively unexplored.We examined how these factors impact learning about nutrition within a cross-sectional study of adults ages 18 to 81. Results showed that conceptual integration mediated the effects of knowledge and WMC on learning, confirming that attention to concepts while reading is important for learning about health. We also found that when knowledge was controlled, age declines in learning increased, suggesting that knowledge mitigates the effects of age on learning about nutrition.

Intimate relationship quality, self-concept and illness acceptance in those with multiple sclerosis.

PubMed

Wright, Thomas M; Kiropoulos, Litza A

2017-02-01

Lower levels of Intimate Relationship Quality (IRQ) have been found in those with Multiple Sclerosis (MS) compared to the general population. This study examined an MS sample to see whether IRQ was positively associated with self-concept, whether IRQ was positively associated with MS illness acceptance and whether IRQ was predicted by self-concept and illness acceptance. In this cross-sectional study, 115 participants with MS who were in an intimate relationship completed an online survey advertised on MS related websites. The survey assessed demographic variables, MS illness variables and levels of IRQ, self-concept and illness acceptance. Results revealed that IRQ was significantly positively associated with self-concept and with illness acceptance. Multiple hierarchical linear regression analysis revealed that, after controlling for illness duration and level of disability, self-concept significantly predicted IRQ but illness acceptance did not significantly predict IRQ. This study addressed several gaps and methodological flaws in the literature and was the first known to assess predictors of IRQ in those with MS. The results suggest that self-concept could be a potential target for individual and couple psychological interventions to improve IRQ and contribute to improved outcomes for those with MS.

Concept for maritime near-surface surveillance using water Raman scattering

DOE PAGES

Shokair, Isaac R.; Johnson, Mark S.; Schmitt, Randal L.; ...

2018-06-08

Here, we discuss a maritime surveillance and detection concept based on Raman scattering of water molecules. Using a range-gated scanning lidar that detects Raman scattered photons from water, the absence or change of signal indicates the presence of a non-water object. With sufficient spatial resolution, a two-dimensional outline of the object can be generated by the scanning lidar. Because Raman scattering is an inelastic process with a relatively large wavelength shift for water, this concept avoids the often problematic elastic scattering for objects at or very close to the water surface or from the bottom surface for shallow waters. Themore » maximum detection depth for this concept is limited by the attenuation of the excitation and return Raman light in water. If excitation in the UV is used, fluorescence can be used for discrimination between organic and non-organic objects. In this paper, we present a lidar model for this concept and discuss results of proof-of-concept measurements. Using published cross section values, the model and measurements are in reasonable agreement and show that a sufficient number of Raman photons can be generated for modest lidar parameters to make this concept useful for near-surface detection.« less

Concept for maritime near-surface surveillance using water Raman scattering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shokair, Isaac R.; Johnson, Mark S.; Schmitt, Randal L.

Here, we discuss a maritime surveillance and detection concept based on Raman scattering of water molecules. Using a range-gated scanning lidar that detects Raman scattered photons from water, the absence or change of signal indicates the presence of a non-water object. With sufficient spatial resolution, a two-dimensional outline of the object can be generated by the scanning lidar. Because Raman scattering is an inelastic process with a relatively large wavelength shift for water, this concept avoids the often problematic elastic scattering for objects at or very close to the water surface or from the bottom surface for shallow waters. Themore » maximum detection depth for this concept is limited by the attenuation of the excitation and return Raman light in water. If excitation in the UV is used, fluorescence can be used for discrimination between organic and non-organic objects. In this paper, we present a lidar model for this concept and discuss results of proof-of-concept measurements. Using published cross section values, the model and measurements are in reasonable agreement and show that a sufficient number of Raman photons can be generated for modest lidar parameters to make this concept useful for near-surface detection.« less

High adiposity is associated cross-sectionally with low self-concept and body size dissatisfaction among indigenous Cree schoolchildren in Canada

PubMed Central

2013-01-01

Background Obesity and mental health problems are prevalent among indigenous children in Canada and the United States. In this cross-sectional study the associations between adiposity and body size satisfaction, body image and self-concept were examined in indigenous children in grades four to six living in Cree communities in the Province of Quebec (Canada). Methods Weight status and body mass index (BMI) z-scores were derived from children’s measured height and weight using the World Health Organization growth reference. Multivariate regression models that included child’s age and sex were used to assess the association between (a) weight status and physical appearance satisfaction using pictorial and verbal body rating measures in 202 of 263 children, and (b) BMI z-score and self-concept measured using the Piers-Harris Children’s Self-Concept Scale in a subset of 78 children. Results Children (10.67 ± 0.98 years) were predominantly overweight (28.2%) or obese (45.0%). Many (40.0%) children had low global self-concept indicating that they had serious doubts about their self-worth and lacked confidence. About one-third (34.7%) of children did not like the way they looked and 46.3% scored low on the physical appearance and attributes domain of self-concept indicating poor self-esteem in relation to their body image and physical strength, feeling unattractive, or being bothered by specific aspects of their physical appearance. Compared to normal weight children, overweight and obese children were more likely to desire being smaller (OR=4.3 and 19.8, respectively), say their body size was too big (OR=7.7 and 30.6, respectively) and not liking the way they looked (OR=2.4 and 7.8, respectively). Higher BMI z-score was associated with lower scores for global self-concept (β=−1.3), intellectual and school status (β=−1.5) and physical appearance and attributes (β=−1.3) indicating negative self-evaluations in these areas. Despite comparable weight status to boys, girls were more likely to have lower scores for global self-concept (β=−3.8), physical appearance and attributes (β=−4.2), desiring to be smaller (OR=4.3) and not liking the way they looked (OR=2.3). Conclusions The psychosocial correlates of obesity are important considerations for indigenous children, particularly girls, given that poor self-concept and body size dissatisfaction negatively impact mental and emotional qualities of life. PMID:23937909

Nursing intellectual capital theory: operationalization and empirical validation of concepts.

PubMed

Covell, Christine L; Sidani, Souraya

2013-08-01

To present the operationalization of concepts in the nursing intellectual capital theory and the results of a methodological study aimed at empirically validating the concepts. The nursing intellectual capital theory proposes that the stocks of nursing knowledge in an organization are embedded in two concepts, nursing human capital and nursing structural capital. The theory also proposes that two concepts in the work environment, nurse staffing and employer support for nursing continuing professional development, influence nursing human capital. A cross-sectional design. A systematic three-step process was used to operationalize the concepts of the theory. In 2008, data were collected for 147 inpatient units from administrative departments and unit managers in 6 Canadian hospitals. Exploratory factor analyses were conducted to determine if the indicator variables accurately reflect their respective concepts. The proposed indicator variables collectively measured the nurse staffing concept. Three indicators were retained to construct nursing human capital: clinical expertise and experience concept. The nursing structural capital and employer support for nursing continuing professional development concepts were not validated empirically. The nurse staffing and the nursing human capital: clinical expertise and experience concepts will be brought forward for further model testing. Refinement for some of the indicator variables of the concepts is indicated. Additional research is required with different sources of data to confirm the findings. © 2012 Blackwell Publishing Ltd.

A Study of the Relationship Between Nurses' Professional Self-Concept and Professional Ethics in Hospitals Affiliated to Jahrom University of Medical Sciences, Iran.

PubMed

Parandavar, Nehleh; Rahmanian, Afifeh; Badiyepeymaie Jahromi, Zohreh

2015-07-31

Commitment to ethics usually results in nurses' better professional performance and advancement. Professional self-concept of nurses refers to their information and beliefs about their roles, values, and behaviors. The objective of this study is to analyze the relationship between nurses' professional self-concept and professional ethics in hospitals affiliated to Jahrom University of Medical Sciences. This cross sectional-analytical study was conducted in 2014. The 270 participants were practicing nurses and head-nurses at the teaching hospitals of Peimanieh and Motahari in Jahrom University of Medical Science. Sampling was based on sencus method. Data was collected using Cowin's Nurses' self-concept questionnaire (NSCQ) and the researcher-made questionnaire of professional ethics. The average of the sample's professional self-concept score was 6.48±0.03 out of 8. The average of the sample's commitment to professional ethics score was 4.08±0.08 out of 5. Based on Pearson's correlation test, there is a significant relationship between professional ethics and professional self-concept (P=0.01, r=0.16). In view of the correlation between professional self-concept and professional ethics, it is recommended that nurses' self-concept, which can boost their commitment to ethics, be given more consideration.

The effect of perceived organisational support on burnout among community health nurses in China: the mediating role of professional self-concept.

PubMed

Cao, Xiaoyi; Chen, Lin; Tian, Lang; Diao, Yongshu

2016-01-01

To examine the mediating effect of professional self-concept on the association between perceived organisational support and burnout among community health nurses in Chengdu, China. Burnout is a common phenomenon among nurses and previous studies have focused on work environmental factors contributing to burnout. Limited studies have examined the effects of perceived organisational support and professional self-concept on burnout among community health nurses. This was a cross-sectional study with 551 community health nurses in Chengdu, China, which included a two-stage sampling method. Structural equation modelling was used to examine the relationships among perceived organisational support, professional self-concept and burnout. The final sample included 456 nurses (82.7%). Perceived organisational support was a significant positive direct predictor for professional self-concept and a significant negative direct predictor for burnout. Professional self-concept was a significant negative direct contributor to burnout. Professional self-concept had a mediating effect on the relationship between perceived organisational support and burnout. Perceived organisational support may result in reduced burnout by facilitating the development of positive professional self-concept. Strategies such as establishing a supportive work environment and professional competence training may be effective methods for burnout prevention and management among community health nurses. © 2015 John Wiley & Sons Ltd.

A Study of the Relationship Between Nurses’ Professional Self-Concept and Professional Ethics in Hospitals Affiliated to Jahrom University of Medical Sciences, Iran

PubMed Central

Parandavar, Nehleh; Rahmanian, Afifeh; Jahromi, Zohreh Badiyepeymaie

2016-01-01

Background: Commitment to ethics usually results in nurses’ better professional performance and advancement. Professional self-concept of nurses refers to their information and beliefs about their roles, values, and behaviors. The objective of this study is to analyze the relationship between nurses’ professional self-concept and professional ethics in hospitals affiliated to Jahrom University of Medical Sciences. Methods: This cross sectional-analytical study was conducted in 2014. The 270 participants were practicing nurses and head-nurses at the teaching hospitals of Peimanieh and Motahari in Jahrom University of Medical Science. Sampling was based on sencus method. Data was collected using Cowin's Nurses’ self-concept questionnaire (NSCQ) and the researcher-made questionnaire of professional ethics. Results: The average of the sample's professional self-concept score was 6.48±0.03 out of 8. The average of the sample's commitment to professional ethics score was 4.08±0.08 out of 5. Based on Pearson's correlation test, there is a significant relationship between professional ethics and professional self-concept (P=0.01, r=0.16). Conclusion: In view of the correlation between professional self-concept and professional ethics, it is recommended that nurses’ self-concept, which can boost their commitment to ethics, be given more consideration. PMID:26573035

Conformal Cryogenic Tank Trade Study for Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Rivers, H. Kevin

1999-01-01

Future reusable launch vehicles may be lifting bodies with non-circular cross section like the proposed Lockheed-Martin VentureStar(tm). Current designs for the cryogenic tanks of these vehicles are dual-lobed and quad-lobed tanks which are packaged more efficiently than circular tanks, but still have low packaging efficiencies with large gaps existing between the vehicle outer mold line and the outer surfaces of the tanks. In this study, tanks that conform to the outer mold line of a non-circular vehicle were investigated. Four structural concepts for conformal cryogenic tanks and a quad-lobed tank concept were optimized for minimum weight designs. The conformal tank concepts included a sandwich tank stiffened with axial tension webs, a sandwich tank stiffened with transverse tension webs, a sandwich tank stiffened with rings and tension ties, and a sandwich tank stiffened with orthogrid stiffeners and tension ties. For each concept, geometric parameters (such as ring frame spacing, the number and spacing of tension ties or webs, and tank corner radius) and internal pressure loads were varied and the structure was optimized using a finite-element-based optimization procedure. Theoretical volumetric weights were calculated by dividing the weight of the barrel section of the tank concept and its associated frames, webs and tension ties by the volume it circumscribes. This paper describes the four conformal tank concepts and the design assumptions utilized in their optimization. The conformal tank optimization results included theoretical weights, trends and comparisons between the concepts, are also presented, along with results from the optimization of a quad-lobed tank. Also, the effects of minimum gauge values and non-optimum weights on the weight of the optimized structure are described in this paper.

A curvilinear, anisotropic, p-version, brick finite element based on geometric entities

NASA Technical Reports Server (NTRS)

Hinnant, Howard E.

1992-01-01

A 'brick' solid finite element is presently developed on the basis of the p-version analysis, and used to demonstrate the FEM concept of 'geometric entities'. This method eliminates interelement discontinuities between low- and high-order elements, allowing very fine control over the shape-function order in various parts of the model. Attention is given to the illustrative cases of a one-element model of an elliptic pipe, and a square cross-section cantilevered beam.

Comparing the Probability Related Misconceptions of Pupils at Different Education Levels=Usporedba pogrješnih predodžaba o konceptima vjerojatnosti kod ucenika razlicitog stupnja obrazovanja

ERIC Educational Resources Information Center

Gürbüz, Ramazan; Birgin, Osman; Çatlioglu, Hakan

2012-01-01

The aim of the paper is to compare and evaluate the probability-related misconceptions of pupils at different education levels. A cross-sectional/age study was thus conducted with 540 pupils in 5th-8th grades. An instrument, comprising six questions on the concepts of compound events, probability of an event and probability comparisons, was used.…

Portuguese primary school children's conceptions about digestion: identification of learning obstacles

NASA Astrophysics Data System (ADS)

Silva, Rui Graça; Lima, Nelson; Coquet, Eduarda; Clément, Pierre

2004-09-01

A cross-sectional study of Portuguese primary school pupils' conceptions on digestion and the digestive tract was carried out before and after teaching this topic. Pupils of the prior four school years (5/6 to 9/10 year old) drew what happens to a cookie inside their body. In some cases they also wrote a short text or were interviewed. To identify their level of graphic development, they produced a free-hand drawing. The main conceptual changes in explaining digestion were strongly linked to teaching. Children's previous conceptions were not epistemological obstacles to learning about digestion. The main obstacles were of didactical origin, as images of primary school books do not represent (i) the path of food from the intestine into the blood, (associated to the epistemological obstacle of the permeability of the gut wall); (ii) a clear continuous tract from stomach to anus, which causes a specific confusion at the intestine level.

The Role of Family Characteristics for Students' Academic Outcomes: A Person-Centered Approach.

PubMed

Häfner, Isabelle; Flunger, Barbara; Dicke, Anna-Lena; Gaspard, Hanna; Brisson, Brigitte M; Nagengast, Benjamin; Trautwein, Ulrich

2017-04-17

Using data from 1,571 ninth-grade students (M age  = 14.62) from 82 academic track schools in Germany and their predominantly Caucasian middle-class parents, configurations of different family characteristics reported by parents were investigated. Latent profile analyses considering academic involvement, family interest, parents' self-concept, child's need for support, and parents' time and energy identified average, indifferent, motivated and engaged, motivated and disengaged, and involved families. Cross-sectional and longitudinal associations with students' motivational (self-concept, effort, and interest) and achievement outcomes (achievement test and grades) in math were analyzed. Students from families classified as motivated and disengaged showed higher initial levels motivation and achievement. Over 5 months, these students also showed an increase in self-concept and higher achievement than students from other family types. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

Self-Concept Clarity and Emotion Dysregulation in Nonsuicidal Self-Injury.

PubMed

Lear, Mary K; Pepper, Carolyn M

2016-12-01

Recent research has linked identity instability with engagement in nonsuicidal self-injury (NSSI; Claes, Luyckx, & Bijttebier, 2014; Claes et al., 2015). This study examined the relationship between self-concept clarity (SCC), an index of identity stability, and NSSI in a sample of 147 college students, using a cross-sectional survey design. The relationship between SCC and emotion dysregulation in NSSI severity was also examined. SCC was significantly negatively associated with NSSI engagement, as well as NSSI frequency and versatility, above negative affect or age. SCC fully accounted for the variance originally explained by emotion dysregulation in NSSI versatility. NSSI frequency was not significantly predicted by emotion regulation, but self-concept clarity reached marginal significance. These findings provide preliminary support for identity instability as a contributing factor to a relationship between emotion dysregulation and NSSI severity. Possible explanations and future research directions are discussed.

Progress in the Phase 0 Model Development of a STAR Concept for Dynamics and Control Testing

NASA Technical Reports Server (NTRS)

Woods-Vedeler, Jessica A.; Armand, Sasan C.

2003-01-01

The paper describes progress in the development of a lightweight, deployable passive Synthetic Thinned Aperture Radiometer (STAR). The spacecraft concept presented will enable the realization of 10 km resolution global soil moisture and ocean salinity measurements at 1.41 GHz. The focus of this work was on definition of an approximately 1/3-scaled, 5-meter Phase 0 test article for concept demonstration and dynamics and control testing. Design requirements, parameters and a multi-parameter, hybrid scaling approach for the dynamically scaled test model were established. The El Scaling Approach that was established allows designers freedom to define the cross section of scaled, lightweight structural components that is most convenient for manufacturing when the mass of the component is small compared to the overall system mass. Static and dynamic response analysis was conducted on analytical models to evaluate system level performance and to optimize panel geometry for optimal tension load distribution.

Black Adolescent Males: Intersections Among Their Gender Role Identity and Racial Identity and Associations With Self-Concept (Global and School).

PubMed

Buckley, Tamara R

2017-09-12

Intersectional approaches for understanding identity have gained momentum in the social sciences. Black adolescent males are often perceived as threatening, underachieving, and hypermasculine, which is reinforced through media outlets and psychological research that portray them as a monolith rather than a heterogeneous group with multiple intersecting identities. This cross-sectional study of 70 Black adolescent males between 14 and 18 years old simultaneously explores their race and gender identities and associations with self-concept (global and school). Results demonstrated that participants reported a combination of feminine and masculine gender roles, rather than hypermasculine. A canonical correlation analysis found that Black racial identity attitudes (RIAS-L) and gender roles simultaneously contributed to significant relationships with total and school self-concept. Study limitations and future directions for research and practice are discussed. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

CRLH-TL Sensors for Flow Inhomogeneties Detection of Pneumatic Conveyed Pulverized Solids

NASA Astrophysics Data System (ADS)

Angelovski, Aleksandar; Penirschke, Andreas; Jakoby, Rolf

2011-08-01

This paper presents an application of a Composite Right/Left-Handed (CRLH) Transmission Line resonator for a compact mass flow detector which is able to detect inhomogeneous flows. In this concept, series capacitors and shunt inductors are used to synthesize a medium with simultaneously negative permeability and permittivity - the so called metamaterial. The helix shape of the cylindrical CRLH-TL sensor offers the possibility to detect flow inhomogeneities within the pipeline which can be used to correct the detected massflow rate. A combination of two CRLH-TL structures within the same cross-section of the pipeline can improve the angular sensitivity of the sensor. A prototype was realized and tested in a dedicated measurement setup to prove the concept.

Temporal scaling of the growth dependent optical properties of microalgae

NASA Astrophysics Data System (ADS)

Zhao, J. M.; Ma, C. Y.; Liu, L. H.

2018-07-01

The optical properties of microalgae are basic parameters for analyzing light field distribution in photobioreactors (PBRs). With the growth of microalgae cell, their optical properties will vary with growth time due to accumulation of pigment and lipid, cell division and metabolism. In this work, we report a temporal scaling behavior of the growth dependent optical properties of microalgae cell suspensions with both experimental and theoretical evidence presented. A new concept, the temporal scaling function (TSF), defined as the ratio of absorption or scattering cross-sections at growth phase to that at stationary phase, is introduced to characterize the temporal scaling behavior. The temporal evolution and temporal scaling characteristics of the absorption and scattering cross-sections of three example microalgae species, Chlorella vulgaris, Chlorella pyrenoidosa, and Chlorella protothecoides, were experimentally studied at spectral range 380-850 nm. It is shown that the TSFs of the absorption and scattering cross-sections for different microalgae species are approximately constant at different wavelength, which confirms theoretical predictions very well. With the aid of the temporal scaling relation, the optical properties at any growth time can be calculated based on those measured at stationary phase, hence opens a new way to determine the time-dependent optical properties of microalgae. The findings of this work will help the understanding of time dependent optical properties of microalgae and facilitate their applications in light field analysis in PBRs design.

Stroke Volume estimation using aortic pressure measurements and aortic cross sectional area: Proof of concept.

PubMed

Kamoi, S; Pretty, C G; Chiew, Y S; Pironet, A; Davidson, S; Desaive, T; Shaw, G M; Chase, J G

2015-08-01

Accurate Stroke Volume (SV) monitoring is essential for patient with cardiovascular dysfunction patients. However, direct SV measurements are not clinically feasible due to the highly invasive nature of measurement devices. Current devices for indirect monitoring of SV are shown to be inaccurate during sudden hemodynamic changes. This paper presents a novel SV estimation using readily available aortic pressure measurements and aortic cross sectional area, using data from a porcine experiment where medical interventions such as fluid replacement, dobutamine infusions, and recruitment maneuvers induced SV changes in a pig with circulatory shock. Measurement of left ventricular volume, proximal aortic pressure, and descending aortic pressure waveforms were made simultaneously during the experiment. From measured data, proximal aortic pressure was separated into reservoir and excess pressures. Beat-to-beat aortic characteristic impedance values were calculated using both aortic pressure measurements and an estimate of the aortic cross sectional area. SV was estimated using the calculated aortic characteristic impedance and excess component of the proximal aorta. The median difference between directly measured SV and estimated SV was -1.4ml with 95% limit of agreement +/- 6.6ml. This method demonstrates that SV can be accurately captured beat-to-beat during sudden changes in hemodynamic state. This novel SV estimation could enable improved cardiac and circulatory treatment in the critical care environment by titrating treatment to the effect on SV.

Prospects of heavy and superheavy element production via inelastic nucleus-nucleus collisions - from 238U+238U to18O+254Es

NASA Astrophysics Data System (ADS)

Schädel, Matthias

2016-12-01

Multi-nucleon transfer reactions, frequently termed deep-inelastic, between heavy-ion projectiles and actinide targets provide prospects to synthesize unknown isotopes of heavy actinides and superheavy elements with neutron numbers beyond present limits. The 238U on 238U reaction, which revealed essential aspects of those nuclear reactions leading to surviving heavy nuclides, mainly produced in 3n and 4n evaporation channels, is discussed in detail. Positions and widths of isotope distributions are compared. It is shown, as a general rule, that cross sections peak at irradiation energies about 10% above the Coulomb barrier. Heavy target nuclei are essential for maximizing cross sections. Experimental results from the 238U on 248Cm reaction, including empirical extrapolations, are compared with theoretical model calculations predicting relatively high cross sections for neutron-rich nuclei. Experiments to test the validity of such predictions are proposed. Comparisons between rather symmetric heavy-ion reactions like 238U on 248Cm (or heavier targets up to 254Es) with very asymmetric ones like 18O on 254Es reveal that the ones with 238U as a projectile have the highest potential in the superheavy element region while the latter ones can be advantageous for the synthesis of heavy actinide isotopes. Concepts for highly efficient recoil separators designed for transfer products are presented.

A balance for dark matter bound states

NASA Astrophysics Data System (ADS)

Nozzoli, F.

2017-05-01

Massive particles with self interactions of the order of 0.2 barn/GeV are intriguing Dark Matter candidates from an astrophysical point of view. Current and past experiments for direct detection of massive Dark Matter particles are focusing to relatively low cross sections with ordinary matter, however they cannot rule out very large cross sections, σ/M > 0.01 barn/GeV, due to atmosphere and material shielding. Cosmology places a strong indirect limit for the presence of large interactions among Dark Matter and baryons in the Universe, however such a limit cannot rule out the existence of a small sub-dominant component of Dark Matter with non negligible interactions with ordinary matter in our galactic halo. Here, the possibility of the existence of bound states with ordinary matter, for a similar Dark Matter candidate with not negligible interactions, is considered. The existence of bound states, with binding energy larger than ∼ 1 meV, would offer the possibility to test in laboratory capture cross sections of the order of a barn (or larger). The signature of the detection for a mass increasing of cryogenic samples, due to the possible particle accumulation, would allow the investigation of these Dark Matter candidates with mass up to the GUT scale. A proof of concept for a possible detection set-up and the evaluation of some noise sources are described.

Looking to the Future: Non-contact Methods for Measuring Streamflow

USGS Publications Warehouse

Costa, J.E.; Cheng, R.T.; Haeni, F.P.; Melcher, N.B.; Spicer, K.R.; Plant, J.; Keller, W.C.; Hayes, K.; Wahl, T.L.; Pugh, C.A.; Oberg, K.A.; Vermeyen, T.B.

2002-01-01

We have conducted a series of proof-of-concept experiments to demonstrate whether it is possible to make completely non-contact open-channel discharge measurements. After an extensive evaluation of potential technologies, we concluded a combination of high-frequency (microwave) radar (for measuring surface velocity) and low-frequency radar (ground-penetrating radar) for measuring channel cross-section, had the best chance for success. The first experiment in 1999 on the Skagit River, Washington, using non-contact methods, produced a discharge value nearly exactly the same as from an ADCP and current meter. Surface-velocity data were converted to mean velocity based on measurements of the velocity profile (multiplied by 0.85), and radar signal speed in impure fresh water was measured to be 0.11-0.12 ft/ns. The weak link was thought to be the requirement to suspend the GPR antenna over the water, which required a bridge or cableway. Two contractors, expert with radar, were unsuccessful in field experiments to measure channel cross-section from the riverbank. Another series of experiments were designed to demonstrate whether both radar systems could be mounted on a helicopter, flown back and forth across a river, and provide data to compute flow. In Sept. 2000 and May 2001, a series of helicopter flights with mounted radar systems successfully measured surface velocity and channel cross-section of the Cowlitz River, Washington.

Electronically cloaked nanoparticles

NASA Astrophysics Data System (ADS)

Shen, Wenqing

The concept of electronic cloaking is to design objects invisible to conduction electrons. The approach of electronic cloaking has been recently suggested to design invisible nanoparticle dopants with electronic scattering cross section smaller than 1% of the physical cross section (pi a2), and therefore to enhance the carrier mobility of bulk materials. The proposed nanoparticles have core-shell structures. The dopants are incorporated inside the core, while the shell layer serves both as a spacer to separate the charge carriers from their parent atoms and as a cloaking shell to minimize the scattering cross section of the electrons from the ionized nanoparticles. Thermoelectric materials are usually highly doped to have enough carrier density. Using invisible dopants could achieve larger thermoelectric power factors by enhancing the electronic mobility. Core-shell nanoparticles show an advantage over one-layer nanoparticles, which are proposed in three-dimensional modulation doping. However designing such nanoparticles is not easy as there are too many parameters to be considered. This thesis first shows an approach to design hollow nanoparticles by applying constrains on variables. In the second part, a simple mapping approach is introduced where one can identify possible core-shell particles by comparing the dimensionless parameters of chosen materials with provided maps. In both parts of this work, several designs with realistic materials were made and proven to achieve electronic cloaking. Improvement in the thermoelectric power factor compared to the traditional impurity doping method was demonstrated in several cases.

Surface Passivation for Reliable Measurement of Bulk Electronic Properties of Heterojunction Devices.

PubMed

Bissig, Benjamin; Guerra-Nunez, Carlos; Carron, Romain; Nishiwaki, Shiro; La Mattina, Fabio; Pianezzi, Fabian; Losio, Paolo A; Avancini, Enrico; Reinhard, Patrick; Haass, Stefan G; Lingg, Martina; Feurer, Thomas; Utke, Ivo; Buecheler, Stephan; Tiwari, Ayodhya N

2016-10-01

Quantum efficiency measurements of state of the art Cu(In,Ga)Se 2 (CIGS) thin film solar cells reveal current losses in the near infrared spectral region. These losses can be ascribed to inadequate optical absorption or poor collection of photogenerated charge carriers. Insight on the limiting mechanism is crucial for the development of more efficient devices. The electron beam induced current measurement technique applied on device cross-sections promises an experimental access to depth resolved information about the charge carrier collection probability. Here, this technique is used to show that charge carrier collection in CIGS deposited by multistage co-evaporation at low temperature is efficient over the optically active region and collection losses are minor as compared to the optical ones. Implications on the favorable absorber design are discussed. Furthermore, it is observed that the measurement is strongly affected by cross-section surface recombination and an accurate determination of the collection efficiency is not possible. Therefore it is proposed and shown that the use of an Al 2 O 3 layer deposited onto the cleaved cross-section significantly improves the accuracy of the measurement by reducing the surface recombination. A model for the passivation mechanism is presented and the passivation concept is extended to other solar cell technologies such as CdTe and Cu 2 (Zn,Sn)(S,Se) 4 . © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Stress measurement in thick plates using nonlinear ultrasonics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abbasi, Zeynab, E-mail: zabbas5@uic.edu, E-mail: dozevin@uic.edu; Ozevin, Didem, E-mail: zabbas5@uic.edu, E-mail: dozevin@uic.edu

2015-03-31

In this paper the interaction between nonlinear ultrasonic characteristics and stress state of complex loaded thick steel plates using fundamental theory of nonlinear ultrasonics is investigated in order to measure the stress state at a given cross section. The measurement concept is based on phased array placement of ultrasonic transmitter-receiver to scan three angles of a given cross section using Rayleigh waves. The change in the ultrasonic data in thick steel plates is influenced by normal and shear stresses; therefore, three measurements are needed to solve the equations simultaneously. Different thickness plates are studied in order to understand the interactionmore » of Rayleigh wave penetration depth and shear stress. The purpose is that as the thickness becomes smaller, the shear stress becomes negligible at the angled measurement. For thicker cross section, shear stress becomes influential if the depth of penetration of Rayleigh wave is greater than the half of the thickness. The influences of plate thickness and ultrasonic frequency on the identification of stress tensor are numerically studied in 3D structural geometry and Murnaghan material model. The experimental component of this study includes uniaxial loading of the plate while measuring ultrasonic wave at three directions (perpendicular, parallel and angled to the loading direction). Instead of rotating transmitter-receiver pair for each test, a device capable of measuring the three angles is designed.« less

Active buckling control of a beam-column with circular cross-section using piezo-elastic supports and integral LQR control

NASA Astrophysics Data System (ADS)

Schaeffner, Maximilian; Götz, Benedict; Platz, Roland

2016-06-01

Buckling of slender beam-columns subject to axial compressive loads represents a critical design constraint for light-weight structures. Active buckling control provides a possibility to stabilize slender beam-columns by active lateral forces or bending moments. In this paper, the potential of active buckling control of an axially loaded beam-column with circular solid cross-section by piezo-elastic supports is investigated experimentally. In the piezo-elastic supports, lateral forces of piezoelectric stack actuators are transformed into bending moments acting in arbitrary directions at the beam-column ends. A mathematical model of the axially loaded beam-column is derived to design an integral linear quadratic regulator (LQR) that stabilizes the system. The effectiveness of the stabilization concept is investigated in an experimental test setup and compared with the uncontrolled system. With the proposed active buckling control it is possible to stabilize the beam-column in arbitrary lateral direction for axial loads up to the theoretical critical buckling load of the system.

Shape control of structures with semi-definite stiffness matrices for adaptive wings

NASA Astrophysics Data System (ADS)

Austin, Fred; Van Nostrand, William C.; Rossi, Michael J.

1993-09-01

Maintaining an optimum-wing cross section during transonic cruise can dramatically reduce the shock-induced drag and can result in significant fuel savings and increased range. Our adaptive-wing concept employs actuators as truss elements of active ribs to reshape the wing cross section by deforming the structure. In our previous work, to derive the shape control- system gain matrix, we developed a procedure that requires the inverse of the stiffness matrix of the structure without the actuators. However, this method cannot be applied to designs where the actuators are required structural elements since the stiffness matrices are singular when the actuator are removed. Consequently, a new method was developed, where the order of the problem is reduced and only the inverse of a small nonsingular partition of the stiffness matrix is required to obtain the desired gain matrix. The procedure was experimentally validated by achieving desired shapes of a physical model of an aircraft-wing rib. The theory and test results are presented.

Chinese and Australian children's understandings of the Earth: a cross cultural study of conceptual development

NASA Astrophysics Data System (ADS)

Tao, Ying; Oliver, Mary; Venville, Grady

2013-06-01

The purpose of this study was to explore Chinese and Australian primary children's conceptual understandings of the Earth. The research was conducted in the interpretive paradigm and was designed to be descriptive with comparative and cross sectional elements. Participants were Year 3 and Year 6 children from three schools in Hunan Province, central south China ( n = 38) and Year 3 and Year 6 children from three schools in Western Australia ( n = 36). In-depth interviews including drawings were carried out to explore the participants' conceptual understandings of the Earth's shape, gravity, day/night cycle and seasons. The results showed that, regardless of different cultures, children from the same year group constructed similar concepts about the Earth. The Year 3 children were more likely than the Year 6 children to demonstrate intuitive conceptions of a round and flat Earth. The Year 6 children were more likely to demonstrate consistent understandings of a spherical Earth. The findings supported the universality of entrenched presuppositions hypothesis. Cultural mediation was found to have a subtle impact on children's understanding of the Earth. A model of conceptual development is proposed.

Air Vehicle Integrated and Technology Research (AVIATR). Task Order 0027: Lighter Than Air (LTA) and Hybrid Aircraft Concept Assessment Tool Development

DTIC Science & Technology

2014-01-01

airships , was taken into consideration when checking cross section dimensions. The top speed chosen to size the engines was 84 knots. The maximum...paramount to understanding the structural design. Engine choice is also critical since long duration missions, typical for airships , heavily...geometry input pages. This may serve as a starting point for a new airship . • Layout is used to define engine , fin and gondola geometry. • Geometry 1

[Trans-Cultural Prevention of Alcohol-Related Disorders in Elderly Immigrants].

PubMed

Bermejo, I; Frank, F

2015-09-01

In migrants alcohol-related problems increase with increasing age. This group, in particular, is hardly reached by alcohol-specific care offers. Thus our project aimed at the identification of target group-specific barriers to health-care use by means of a cross-sectional study (n=435). Based on these results a trans-cultural concept for alcohol prevention among elderly migrants was developed and evaluated in a cluster-randomised controlled trial (n=176). © Georg Thieme Verlag KG Stuttgart · New York.

Novel Concepts for Conformal Load-Bearing Antenna Structure

DTIC Science & Technology

2008-02-01

through the entire cross-section of a conductor as visualised in the classical “water- through-a-garden- hose ” explanation of DC current flow. Rather, RF...these fabrics were 6k T650 carbon fibre tows braided into unidirectional fabrics. The 6k tows in these fabrics were oriented in the 0° direction and...90]s lay-up 0.050 DSF0302 Standard aerospace prepreg tape [±45]s lay-up 0.061 DSF0601 Braided standard carbon fibres/Standard resin 6k T650

Modular Track System For Positioning Mobile Robots

NASA Technical Reports Server (NTRS)

Miller, Jeff

1995-01-01

Conceptual system for positioning mobile robotic manipulators on large main structure includes modular tracks and ancillary structures assembled easily along with main structure. System, called "tracked robotic location system" (TROLS), originally intended for application to platforms in outer space, but TROLS concept might also prove useful on Earth; for example, to position robots in factories and warehouses. T-cross-section rail keeps mobile robot on track. Bar codes mark locations along track. Each robot equipped with bar-code-recognizing circuitry so it quickly finds way to assigned location.

Aircraft Engine Nacelle Fire Test Simulator. Volume I. Technical.

DTIC Science & Technology

1980-04-01

THIS IPAa@f[h Daal 3MatfeeJ V .. . . .. --.-- - - -- , • PREFACE This report documents the results of the work efforts under Contract No. F33615-76-C...overview of the simulator and its associated equipment capabilities, as compared to the Contract Work Statement performance goals and baseline concepts, is...duct where it pene- trates the roof, and then transitions into a 18" x 36" rectangular cross section of equal area against the east wall of I-Bay. This

Surrogacy and the ECtHR: Reflections on Paradiso and Campanelli v Italy.

PubMed

Iliadou, Marianna

2018-02-21

This case note analyses the recent judgment of the European Court of Human Rights in Paradiso and Campanelli v Italy and examines its implications for cross-border surrogacy in Europe. It is argued that this judgment is highly significant, because it sets new standards in terms of the concept of family life under Article 8 of the European Convention on Human Rights. This judgment, it is argued, only appears to bring a halt to the (seemingly) backdoor legitimacy of commercial surrogacy established by the findings of the Second Section and previous judgments of the Court. Finally, this case note critiques the Grand Chamber's findings and examines its likely impact on the problem of cross-border surrogacy.

Mechanical restoration of large-scale folded multilayers using the finite element method: Application to the Zagros Simply Folded Belt, N-Iraq

NASA Astrophysics Data System (ADS)

Frehner, Marcel; Reif, Daniel; Grasemann, Bernhard

2010-05-01

There are a large number of numerical finite element studies concerned with modeling the evolution of folded geological layers through time. This body of research includes many aspects of folding and many different approaches, such as two- and three-dimensional studies, single-layer folding, detachment folding, development of chevron folds, Newtonian, power-law viscous and more complex rheologies, influence of anisotropy, pure-shear, simple-shear and other boundary conditions and so forth. In recent years, studies of multilayer folding emerged, thanks to more advanced mesh generator software and increased computational power. Common to all of these studies is the fact that they consider a forward directed time evolution, as in nature. Very few studies use the finite element method for reverse-time simulations. In such studies, folded geological layers are taken as initial conditions for the numerical simulation. The folding process is reversed by changing the signs of the boundary conditions that supposedly drove the folding process. In such studies, the geometry of the geological layers before the folding process is searched and the amount of shortening necessary for the final folded geometry can be calculated. In contrast to a kinematic or geometric fold restoration procedure, the described approach takes the mechanical behavior of the geological layers into account, such as rheology and the relative strength of the individual layers. This approach is therefore called mechanical restoration of folds. In this study, the concept of mechanical restoration is applied to a two-dimensional 50km long NE-SW-cross-section through the Zagros Simply Folded Belt in Iraqi Kurdistan, NE from the city of Erbil. The Simply Folded Belt is dominated by gentle to open folding and faults are either absent or record only minor offset. Therefore, this region is ideal for testing the concept of mechanical restoration. The profile used is constructed from structural field measurements and digital elevation models using the dip-domain method for balancing the cross-section. The lithology consists of Cretaceous to Cenozoic sediments. Massive carbonate rock units act as the competent layers compared to the incompetent behavior of siltstone, claystone and marl layers. We show the first results of the mechanical restoration of the Zagros cross-section and we discuss advantages and disadvantages, as well as some technical aspects of the applied method. First results indicate that a shortening of at least 50% was necessary to create the present-day folded cross-section. This value is higher than estimates of the amount of shortening solely based on kinematic or geometric restoration. One particular problem that is discussed is the presence of (unnaturally) sharp edges in a balanced cross-section produced using the dip-domain method, which need to be eliminated for mechanical restoration calculations to get reasonable results.

Transit vehicle-to-infrastructure (V2I) applications : near term research and development. Transit bus-pedestrian/cyclist crossing safety application : operational concept.

DOT National Transportation Integrated Search

2013-11-01

This document serves as an Operational Concept for the Transit Bus-Pedestrian/Cyclist Crossing Safety application. The purpose of this document is to provide an operational description of how the Transit Bus-Pedestrian/Cyclist Crossing Safety W...

a Time-Dependent Many-Electron Approach to Atomic and Molecular Interactions

NASA Astrophysics Data System (ADS)

Runge, Keith

A new methodology is developed for the description of electronic rearrangement in atomic and molecular collisions. Using the eikonal representation of the total wavefunction, time -dependent equations are derived for the electronic densities within the time-dependent Hartree-Fock approximation. An averaged effective potential which ensures time reversal invariance is used to describe the effect of the fast electronic transitions on the slower nuclear motions. Electron translation factors (ETF) are introduced to eliminate spurious asymptotic couplings, and a local ETF is incorporated into a basis of traveling atomic orbitals. A reference density is used to describe local electronic relaxation and to account for the time propagation of fast and slow motions, and is shown to lead to an efficient integration scheme. Expressions for time-dependent electronic populations and polarization parameters are given. Electronic integrals over Gaussians including ETFs are derived to extend electronic state calculations to dynamical phenomena. Results of the method are in good agreement with experimental data for charge transfer integral cross sections over a projectile energy range of three orders of magnitude in the proton-Hydrogen atom system. The more demanding calculations of integral alignment, state-to-state integral cross sections, and differential cross sections are found to agree well with experimental data provided care is taken to include ETFs in the calculation of electronic integrals and to choose the appropriate effective potential. The method is found to be in good agreement with experimental data for the calculation of charge transfer integral cross sections and state-to-state integral cross sections in the one-electron heteronuclear Helium(2+)-Hydrogen atom system and in the two-electron system, Hydrogen atom-Hydrogen atom. Time-dependent electronic populations are seen to oscillate rapidly in the midst of collision event. In particular, multiple exchanges of the electron are seen to occur in the proton-Hydrogen atom system at low collision energies. The concepts and results derived from the approach provide new insight into the dynamics of nuclear screening and electronic rearrangement in atomic collisions.

[Self-concept level in children with burns sequelae: A comparative study].

PubMed

Castillo C, Carmen; Santander M, Dolores; Solís F, Fresia

2015-01-01

Self-concept is the set of ideas and attitudes that a person has about him/herself. To evaluate whether there are differences in the level of self-concept in children 8-12 years old with and without burns sequelae. To identify predictive variables of self-concept in children with sequelae. A comparative cross-sectional study of self-concept in 109 children with burns sequelae, from 8 to 12 years old, with 109 children without burns sequelae, and of the same age and socioeconomic status. The Piers-Harris self-concept scale is used, which provides a general measurement of self-concept and behavioural, intellectual and school status, appearance, and physical attributes, anxiety, popularity, happiness and satisfaction dimensions. There were no significant differences in the level of general self-concept or their dimensions (P>.05). In the group with burns sequelae, the protective factor was the variable number of sequels was associated with the dimensions of anxiety, popularity, happiness-satisfaction and general self-concept. The location variable emerged as a risk factor for the behavioural dimension. The absence of differences in self-concept between children with burns sequelae and children without them is similar to that reported in the literature. The finding in the risk and protective factors encourages to further research, and perhaps incorporating pre-morbidity and family background. Copyright © 2015 Sociedad Chilena de Pediatría. Publicado por Elsevier España, S.L.U. All rights reserved.

Patients' Dignity and Its Relationship with Contextual Variables: A Cross-Sectional Study.

PubMed

Zirak, Mohammad; Ghafourifard, Mansour; Aliafsari Mamaghani, Ebrahim

2017-03-01

Introduction: Dignity is considered as fundamental human needs and recognized as one of the central concepts in nursing science. The aim of this study was to assess the extent to which patients' dignity is respected and to evalutae its relationship with contextual variables. Methods: This cross-sectional study was conducted on 256 hospitalized patients in the two teaching hospitals affiliated to Zanjan University of medical sciences, Iran. Data were collected by a questionnaire consist of two sections: (a) demographic characteristics, and (b) patient dignity including 32 questions. Data were analyzed by SPSS (ver.13) software using independent t-test, ANOVA and Pearson correlation. Results: The result showed that the mean (standard deviation) of total score of patient's dignity was 108.17 (25.28). According to the result, the majority of the respondents (76.2%) were not aware of patient's rights. There was a significant difference in mean scores of total dignity between single and married persons, living in city or village, and hospitalization in Moosavi and Valiasr hospital. Conclusion: Health care systems should take the provision of the patients' dignity into account through using a comprehensive educational program for informing of patient, family members, and health professionals about patients' dignity.

Visual illusions and ethnocentrism: exemplars for teaching cross-cultural concepts.

PubMed

Keith, Kenneth D

2012-05-01

This article discusses the origins of cross-cultural interest in two concepts fundamental to psychology students' views of the world: simple visual illusions and ethnocentrism. Although students encounter these ideas in introductory psychology, textbooks rarely describe the nature or origin of cross-cultural knowledge about them. The article presents a brief account of the history of these concepts and relates them to contemporary notions of psychology and culture. Using visual perception and ethnocentrism as examples, the article suggests the importance of teaching that different people see the world in different ways and the role of that lesson in a future demanding increased cross-cultural understanding.

Climacteric symptoms and their relation to feminine self-concept.

PubMed

Quiroga, A; Larroy, C; González-Castro, P

2017-06-01

To investigate women's subjective experiences in the climacteric transition, especially the impact of self-concept, quality of life and depression on the severity of climacteric symptoms. Non-experimental, cross-sectional study, purpose sampling. To analyze the results, we proposed a three-way interaction, in which the direct effect of depression on the severity of climacteric symptoms would be buffered by perceived sexual quality of life, and mediated by self-concept. As hypothesized, depression significantly predicted self-concept, which in turn mediated the severity of climacteric symptoms. In a second stage of the model, sexual quality of life moderated the direct effect of depression on climacteric symptoms, such that women with a better sexual quality of life would perceive less severity of climacteric symptoms than those with a less favorable sexual quality of life. Physical quality of life did not significantly buffer the direct effect of depression on climacteric symptoms, nor did vasomotor or psychosocial quality of life. Our study confirmed the impact of subjective factors such as satisfaction, self-concept, and quality of life on climacteric symptoms; specifically, we observed the moderating effect of the sexual quality of life on the previously established correlation between depression and aggravation of climacteric symptoms.

Social capital: theory, evidence, and implications for oral health.

PubMed

Rouxel, Patrick L; Heilmann, Anja; Aida, Jun; Tsakos, Georgios; Watt, Richard G

2015-04-01

In the last two decades, there has been increasing application of the concept of social capital in various fields of public health, including oral health. However, social capital is a contested concept with debates on its definition, measurement, and application. This study provides an overview of the concept of social capital, highlights the various pathways linking social capital to health, and discusses the potential implication of this concept for health policy. An extensive and diverse international literature has examined the relationship between social capital and a range of general health outcomes across the life course. A more limited but expanding literature has also demonstrated the potential influence of social capital on oral health. Much of the evidence in relation to oral health is limited by methodological shortcomings mainly related to the measurement of social capital, cross-sectional study designs, and inadequate controls for confounding factors. Further research using stronger methodological designs should explore the role of social capital in oral health and assess its potential application in the development of oral health improvement interventions. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Motivational interviewing skills are positively associated with nutritionist self-efficacy.

PubMed

Marley, Scott C; Carbonneau, Kira; Lockner, Donna; Kibbe, Debra; Trowbridge, Frederick

2011-01-01

To examine the relationships between physical and social self-concepts, motivational interviewing (MI), and nutrition assessment skills with dimensions of counseling self-efficacy. Cross-sectional survey. Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) clinics. Sixty-five WIC nutritionists. Counseling self-efficacy on topics related to physical activity and nutritional behaviors and in the presence of language and cultural differences. Multiple linear regression. Nutritionists' perception of their own MI skills was positively associated with their self-efficacy for counseling clients of a culture different than their own, when counseling about physical activity, and when counseling about nutrition behavior. Hispanic ethnicity and social self-concept were positively associated with counseling self-efficacy when culture differences were present. Physical self-concept was positively associated with self-efficacy related to physical activity topics. Nutrition assessment skill was negatively associated with self-efficacy for working with non-English-speaking clients. Development of MI skills and strategies to improve social and physical self-concept may increase WIC nutritionists' counseling self-efficacy, particularly when counseling clients from diverse backgrounds. Copyright © 2011 Society for Nutrition Education. Published by Elsevier Inc. All rights reserved.

Screen time, weight status and the self-concept of physical attractiveness in adolescents.

PubMed

Suchert, Vivien; Hanewinkel, Reiner; Isensee, Barbara

2016-04-01

Adolescents in modern societies spend about 3 h per day in front of small recreational screens. The present study aims at investigating the relationships between screen time and different indicators of overweight. In addition, associations with the self-concept of physical attractiveness and perceived weight status will be examined. In a total sample of 1228 students (47.5% girls) aged 12-17 years (M = 13.74, SD = 0.68) cross-sectional associations were determined by conducting multiple linear regression analyses. Screen time showed a significant positive dose-response relationship with body mass index percentile, waist circumference, body fat, waist-to-height-ratio, and a negative association with self-concept of physical attractiveness independent of age, gender and moderate to vigorous physical activity. Thus, screen time seems to be associated with adolescent overweight, abdominal obesity, and body dissatisfaction. Reducing adolescents' screen time could be a promising approach for primary prevention of obesity and for the promotion of a positive physical self-concept. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.

A cross-sectional study of chiropractic students' research readiness using the Academic Self-Concept Analysis Scale.

PubMed

Whillier, Stephney; Au, Kent; Feng, Louie; Su, Helen

2017-10-01

The shift toward evidence-based health care has reoriented tertiary clinical education in a way that necessitates and incorporates research. This study assesses the inclination and suitability of chiropractic students for research over a 5-year educational program. Research attributes of chiropractic students were assessed in this cross-sectional study using a validated and modified academic self-concept analysis scale. Students in first and final year were assessed in 4 domains: creativity, motivation, self-regulation, and general intellectual ability. Univariable differences were assessed using Welch 2-sample t tests, and multivariable analysis was carried out with multiple linear regression models. The response rate was 71% (n = 165). First- and fifth-year students scored highly on all 4 domains (80% to 96%). Compared to first-year students, fifth-year students rated themselves significantly lower in 3 of the domains: general intellectual abilities (t[126] = -2.01; p = 0.047), motivation (t[115] = -4.82; p < 0.001), and creativity (t[136] = -3.00; p = 0.003). Research suitability is high in chiropractic students. Both cohorts scored high in all domains despite the disparity between first and fifth years. First-year students outperformed fifth-year students in 3 domains, indicating a potential decline in the inclination to do research over time. However, unaccounted factors, such as the Dunning-Kruger effect, life changes, and "burnout," may have contributed to these differences. Future studies should include questions about stress, fatigue, clinical orientation, and educational environment to inform the interpretation of findings.

Consumer appeal of nutrition and health claims in three existing product concepts.

PubMed

Verbeke, Wim; Scholderer, Joachim; Lähteenmäki, Liisa

2009-06-01

This paper reports on consumers' reactions towards calcium-enriched fruit juice, omega-3 enriched spread and fibre-enriched cereals, each with a nutrition claim, health claim and reduction of disease risk claim. Cross-sectional data were collected in April 2006 from a sample of 341 consumers in Belgium. Consumers' reactions to the carrier product, functional ingredient and claim combinations were assessed as perceived convincingness of the claim, credibility of the product, attractiveness of the product, and intention to buy the product, while accounting for differences in product familiarity, attitudinal and demographic characteristics. Generally, health claims outperformed nutrition claims, and both of these claim types outperformed reduction of disease risk claims. Comparing consumer reactions across product concepts revealed clear preferences for fibre-enriched cereals as compared to the other two concepts. The interaction effects between claim type and product concept indicated that reduction of disease risk claims are perceived very well in omega-3 enriched spreads, particularly in terms of perceived convincingness of the claim, while not appealing to consumers in the other product concepts. Positive attitudes towards functional foods and familiarity with the concrete functional product category boosted the claim type and product ratings, whereas perceived control over own health and perceiving functional foods as a marketing scam decreased all product concept's appeal.

Effect of professional self-concept on burnout among community health nurses in Chengdu, China: the mediator role of organisational commitment.

PubMed

Cao, Xiaoyi; Chen, Lin; Tian, Lang; Diao, Yongshu; Hu, Xiuying

2015-10-01

To examine the associations among professional self-concept, organisational commitment and burnout, and to analyse the mediating role of organisational commitment on the relationship between professional self-concept and burnout among community health nurses in Chengdu, China. Previous studies have focused on work environmental variables that contributed to burnout in nurses. However, no study has explored the mediating effect of organisational commitment on the correlation between professional self-concept and burnout in community health nurses. A cross-sectional descriptive study. This study was conducted at 36 community health centres in Chengdu, China with 485 nurses sampled using a two-stage sampling method. The measures used in our study included Nurses' Self-concept Questionnaire, Organisational Commitment Scale and Maslach Burnout Inventory. The results of structural equation model techniques indicated that, in the direct approach, positive professional self-concept resulted in increased organisational commitment and reduced burnout. Higher organisational commitment resulted in less burnout. In the indirect approach, organisational commitment performed as a partial mediator on the correlation between professional self-concept and burnout. Positive perception of professional self-concept can result in reduced burnout via enhancing organisational commitment. It is crucial for nursing administrators to develop effective intervention strategies such as skills escalator training and assertive training, and establishing a supportive working environment to enhance nurses' professional self-concept and organisational commitment, and decrease burnout. © 2015 John Wiley & Sons Ltd.

Thermogenic Wet Gas in Immature Caprock Sections: Leakage or Generation.

NASA Astrophysics Data System (ADS)

Abrakasa, Selegha; Beka, Francis; Ndukauba, Egesi

2017-04-01

Gas geochemistry, an aspect of Petroleum Geoscience is a growing science, various concepts has been used to evaluation potential source rock for shale gas while in conventional petroleum exploration similar concepts have been used to determine potential productive formation for liquid hydrocarbons. Prior to the present times, headspace gas data had been used to recognize by pass pays, serve as indicators of petroleum accumulations, evaluate maturity and productive capacity of corresponding formations, evaluate the maturity and source of gas accumulations. Integrating studies in bid to achieve high degree of accuracy, data on direct hydrocarbon indicators (DHIs) such as oil stains, oil shows and seeps have been employed. Currently popular among professionals is the use of gas clouds on seismic cross sections. In contemporary times, advancement in gas geochemistry has witnessed the application of concepts on headspace gas to expound the efficiency of petroleum caprocks whose major role is to foster accumulation and preservation. This enables extricating potential leakage mechanism via caprock reservoir interface and unravel its corresponding migrational pathways. In this study thermogenic wet gas has been used as a dependable tool for delineating caprock leakage by discriminating migrant from indigenous hydrocarbons in caprock rock sections overlying the reservoirs. The thermogenic gas profile in corroboration with the thermogenic signature and maturity data were used. Summary statistics indicates that 60% of the 50 wells studied has wet gas up to 500m above the reservoir-caprock interface and 10% of the leaking wells are fracture prone leakage.The amount of wet gas ranges of up to 200,000 ppm in the caprock sections, this indicates pervasive leakage. Log view plots were modelled using Schlumbergers' Techlog, while descriptive lithologies were modeled using Zetawares' genesis.

Cross support overview and operations concept for future space missions

NASA Technical Reports Server (NTRS)

Stallings, William; Kaufeler, Jean-Francois

1994-01-01

Ground networks must respond to the requirements of future missions, which include smaller sizes, tighter budgets, increased numbers, and shorter development schedules. The Consultative Committee for Space Data Systems (CCSDS) is meeting these challenges by developing a general cross support concept, reference model, and service specifications for Space Link Extension services for space missions involving cross support among Space Agencies. This paper identifies and bounds the problem, describes the need to extend Space Link services, gives an overview of the operations concept, and introduces complimentary CCSDS work on standardizing Space Link Extension services.

Regional curve development and selection of a reference reach in the non-urban, lowland sections of the Piedmont physiographic province, Pennsylvania and Maryland

USGS Publications Warehouse

White, Kirk E.

2001-01-01

Stream-restoration projects utilizing naturalstream designs frequently are based on the bankfull- channel characteristics of a stream reach that is accommodating streamflow and sediment transport without excessive erosion or deposition. The bankfull channel is identified by the use of field indicators and confirmed with tools such as regional curves. Channel dimensions were surveyed at six streamflow-measurement stations operated by the U.S. Geological Survey in the Gettysburg-Newark Lowlands Section and Piedmont Lowlands Section of the Piedmont Physiographic Province in Pennsylvania and Maryland. Regional curves were developed from regression analyses of the relation between drainage area and cross-sectional area, mean depth, width, and streamflow of the bankfull channel. Regional curves were used to confirm the identification of the bankfull channel at a reference reach. Stream dimensions and characteristics of the reference reach were measured for extrapolation into the design of a steam-restoration project on Bermudian Creek in Adams County, Pa.Dimensions for cross-sectional area, mean depth, width, and computed streamflow of the bankfull channel in all surveyed riffle cross sections in the reference reach were within the 95-percent confidence interval bounding the regression line representing bankfull channel geometry in the Lowland Sections of the Piedmont Physiographic Province. The average bankfull cross-sectional area, bankfull mean depth, and computed bankfull discharge for riffle cross sections in the reference reach ranged from 15.4 to 16.5 percent less than estimates determined from the lowland regional curves. Average bankfull channel width was about 2 percent greater than estimates. Cross-sectional area, mean depth, and computed streamflow corresponding to the bankfull stage at the reference reach were 31.4, 44.4, and 9.6 percent less, respectively, than estimates derived from the regional curves developed by Dunne and Leopold in 1978. Average bankfull channel width at the reference reach was 16.7 percent greater than the Dunne and Leopold estimate.The concepts of regional curves and reference reaches can be valuable tools to support efforts in stream restoration. Practitioners of stream restoration need to recognize them as such and realize their limitations. The small number of stations available for analysis is a major limiting factor in the strength of the results of this investigation. Subjective selection criteria may have unnecessarily eliminated streamflow-measurement stations that could have been included in the regional curves. A bankfull discharge with a recurrence interval within the 1- to 2-year range was used as a criteria for confirmation of the bankfull stage at each streamflow-measurement station. Many researchers accept this range for recurrence interval of the bankfull discharge; however, literature provides contradictory evidence. The use of channel-characteristics data from a reference reach without any monitoring data to document the stability of the reference reach over time is a topic of debate.

Students' Energy Understanding Across Biology, Chemistry, and Physics Contexts

NASA Astrophysics Data System (ADS)

Opitz, S. T.; Neumann, K.; Bernholt, S.; Harms, U.

2017-07-01

Energy is considered both as a disciplinary core idea and as a concept cutting across science disciplines. Most previous approaches studied progressing energy understanding in specific disciplinary contexts, while disregarding the relation of understanding across them. Hence, this study provides a systematic analysis of cross-disciplinary energy learning. On the basis of a cross-sectional study with n = 742 students from grades 6, 8, and 10, we analyze students' progression in understanding energy across biology, chemistry, and physics contexts. The study is guided by three hypothetical scenarios that describe how the connection between energy understanding in the three disciplinary contexts changes across grade levels. These scenarios are compared using confirmatory factor analysis (CFA). The results suggest that, from grade 6 to grade 10, energy understanding in the three disciplinary contexts is highly interrelated, thus indicating a parallel progression of energy understanding in the three disciplinary contexts. In our study, students from grade 6 onwards appeared to have few problems to apply one energy understanding across the three disciplinary contexts. These findings were unexpected, as previous research concluded that students likely face difficulties in connecting energy learning across disciplinary boundaries. Potential reasons for these results and the characteristics of the observed cross-disciplinary energy understanding are discussed in the light of earlier findings and implications for future research, and the teaching of energy as a core idea and a crosscutting concept are addressed.

Boricua de pura cepa: Ethnic identity, cultural stress and self-concept in Puerto Rican youth.

PubMed

Zhen-Duan, Jenny; Jacquez, Farrah; Sáez-Santiago, Emily

2018-05-17

The available literature on ethnic identity among Puerto Ricans has focused on those living in the United States, with little to no attention placed on examining ethnic identity and psychological constructs among youth living in Puerto Rico. Using a colonial mentality framework, the current study examined the associations between ethnic identity, cultural stress, and self-concept among adolescent boys and girls living in Puerto Rico. The current cross-sectional study surveyed participants (N = 187) recruited from several junior high schools in the metropolitan area in Puerto Rico. Relations between ethnic identity, cultural stress, and self-concept differed by gender. First, cultural stress was associated with self-concept for boys, such that higher cultural stress predicted lower self-concept. Second, among girls, cultural stress moderated the relation between ethnic identity and self-concept. Specifically, for girls experiencing high cultural stress, exploration and resolution of their ethnic identity was associated with higher ratings of self-concept. Although cultural stress has been widely understood as a phenomena associated with immigrants, our study indicated that cultural stress is important in understanding self-concept of youth living in Puerto Rico. For boys, cultural stress, but not ethnic identity, is particularly important to their self-concept. Among girls experiencing high cultural stress, exploration and resolution of ethnic identity was associated with higher self-concept. Results suggested that the cultural stress associated with the colonial context of Puerto Rico is salient in ethnic identity and self-concept development, even though Puerto Rican youth are the ethnic majority in the island. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Computing under-ice discharge: A proof-of-concept using hydroacoustics and the Probability Concept

NASA Astrophysics Data System (ADS)

Fulton, John W.; Henneberg, Mark F.; Mills, Taylor J.; Kohn, Michael S.; Epstein, Brian; Hittle, Elizabeth A.; Damschen, William C.; Laveau, Christopher D.; Lambrecht, Jason M.; Farmer, William H.

2018-07-01

Under-ice discharge is estimated using open-water reference hydrographs; however, the ratings for ice-affected sites are generally qualified as poor. The U.S. Geological Survey (USGS), in collaboration with the Colorado Water Conservation Board, conducted a proof-of-concept to develop an alternative method for computing under-ice discharge using hydroacoustics and the Probability Concept. The study site was located south of Minturn, Colorado (CO), USA, and was selected because of (1) its proximity to the existing USGS streamgage 09064600 Eagle River near Minturn, CO, and (2) its ease-of-access to verify discharge using a variety of conventional methods. From late September 2014 to early March 2015, hydraulic conditions varied from open water to under ice. These temporal changes led to variations in water depth and velocity. Hydroacoustics (tethered and uplooking acoustic Doppler current profilers and acoustic Doppler velocimeters) were deployed to measure the vertical-velocity profile at a singularly important vertical of the channel-cross section. Because the velocity profile was non-standard and cannot be characterized using a Power Law or Log Law, velocity data were analyzed using the Probability Concept, which is a probabilistic formulation of the velocity distribution. The Probability Concept-derived discharge was compared to conventional methods including stage-discharge and index-velocity ratings and concurrent field measurements; each is complicated by the dynamics of ice formation, pressure influences on stage measurements, and variations in cross-sectional area due to ice formation. No particular discharge method was assigned as truth. Rather one statistical metric (Kolmogorov-Smirnov; KS), agreement plots, and concurrent measurements provided a measure of comparability between various methods. Regardless of the method employed, comparisons between each method revealed encouraging results depending on the flow conditions and the absence or presence of ice cover. For example, during lower discharges dominated by under-ice and transition (intermittent open-water and under-ice) conditions, the KS metric suggests there is not sufficient information to reject the null hypothesis and implies that the Probability Concept and index-velocity rating represent similar distributions. During high-flow, open-water conditions, the comparisons are less definitive; therefore, it is important that the appropriate analytical method and instrumentation be selected. Six conventional discharge measurements were collected concurrently with Probability Concept-derived discharges with percent differences (%) of -9.0%, -21%, -8.6%, 17.8%, 3.6%, and -2.3%. This proof-of-concept demonstrates that riverine discharges can be computed using the Probability Concept for a range of hydraulic extremes (variations in discharge, open-water and under-ice conditions) immediately after the siting phase is complete, which typically requires one day. Computing real-time discharges is particularly important at sites, where (1) new streamgages are planned, (2) river hydraulics are complex, and (3) shifts in the stage-discharge rating are needed to correct the streamflow record. Use of the Probability Concept does not preclude the need to maintain a stage-area relation. Both the Probability Concept and index-velocity rating offer water-resource managers and decision makers alternatives for computing real-time discharge for open-water and under-ice conditions.

Computing under-ice discharge: A proof-of-concept using hydroacoustics and the Probability Concept

USGS Publications Warehouse

Fulton, John W.; Henneberg, Mark F.; Mills, Taylor J.; Kohn, Michael S.; Epstein, Brian; Hittle, Elizabeth A.; Damschen, William C.; Laveau, Christopher D.; Lambrecht, Jason M.; Farmer, William H.

2018-01-01

Under-ice discharge is estimated using open-water reference hydrographs; however, the ratings for ice-affected sites are generally qualified as poor. The U.S. Geological Survey (USGS), in collaboration with the Colorado Water Conservation Board, conducted a proof-of-concept to develop an alternative method for computing under-ice discharge using hydroacoustics and the Probability Concept.The study site was located south of Minturn, Colorado (CO), USA, and was selected because of (1) its proximity to the existing USGS streamgage 09064600 Eagle River near Minturn, CO, and (2) its ease-of-access to verify discharge using a variety of conventional methods. From late September 2014 to early March 2015, hydraulic conditions varied from open water to under ice. These temporal changes led to variations in water depth and velocity. Hydroacoustics (tethered and uplooking acoustic Doppler current profilers and acoustic Doppler velocimeters) were deployed to measure the vertical-velocity profile at a singularly important vertical of the channel-cross section. Because the velocity profile was non-standard and cannot be characterized using a Power Law or Log Law, velocity data were analyzed using the Probability Concept, which is a probabilistic formulation of the velocity distribution. The Probability Concept-derived discharge was compared to conventional methods including stage-discharge and index-velocity ratings and concurrent field measurements; each is complicated by the dynamics of ice formation, pressure influences on stage measurements, and variations in cross-sectional area due to ice formation.No particular discharge method was assigned as truth. Rather one statistical metric (Kolmogorov-Smirnov; KS), agreement plots, and concurrent measurements provided a measure of comparability between various methods. Regardless of the method employed, comparisons between each method revealed encouraging results depending on the flow conditions and the absence or presence of ice cover.For example, during lower discharges dominated by under-ice and transition (intermittent open-water and under-ice) conditions, the KS metric suggests there is not sufficient information to reject the null hypothesis and implies that the Probability Concept and index-velocity rating represent similar distributions. During high-flow, open-water conditions, the comparisons are less definitive; therefore, it is important that the appropriate analytical method and instrumentation be selected. Six conventional discharge measurements were collected concurrently with Probability Concept-derived discharges with percent differences (%) of −9.0%, −21%, −8.6%, 17.8%, 3.6%, and −2.3%.This proof-of-concept demonstrates that riverine discharges can be computed using the Probability Concept for a range of hydraulic extremes (variations in discharge, open-water and under-ice conditions) immediately after the siting phase is complete, which typically requires one day. Computing real-time discharges is particularly important at sites, where (1) new streamgages are planned, (2) river hydraulics are complex, and (3) shifts in the stage-discharge rating are needed to correct the streamflow record. Use of the Probability Concept does not preclude the need to maintain a stage-area relation. Both the Probability Concept and index-velocity rating offer water-resource managers and decision makers alternatives for computing real-time discharge for open-water and under-ice conditions.

STEMing the tide: using ingroup experts to inoculate women's self-concept in science, technology, engineering, and mathematics (STEM).

PubMed

Stout, Jane G; Dasgupta, Nilanjana; Hunsinger, Matthew; McManus, Melissa A

2011-02-01

Three studies tested a stereotype inoculation model, which proposed that contact with same-sex experts (advanced peers, professionals, professors) in academic environments involving science, technology, engineering, and mathematics (STEM) enhances women's self-concept in STEM, attitudes toward STEM, and motivation to pursue STEM careers. Two cross-sectional controlled experiments and 1 longitudinal naturalistic study in a calculus class revealed that exposure to female STEM experts promoted positive implicit attitudes and stronger implicit identification with STEM (Studies 1-3), greater self-efficacy in STEM (Study 3), and more effort on STEM tests (Study 1). Studies 2 and 3 suggested that the benefit of seeing same-sex experts is driven by greater subjective identification and connectedness with these individuals, which in turn predicts enhanced self-efficacy, domain identification, and commitment to pursue STEM careers. Importantly, women's own self-concept benefited from contact with female experts even though negative stereotypes about their gender and STEM remained active. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Self-Identity After Bereavement: Reduced Self-Clarity and Loss-Centrality in Emotional Problems After the Death of a Loved One.

PubMed

Boelen, Paul A

2017-05-01

There is evidence that both the centrality of a loss-event as well as reduced self-concept clarity are involved in emotional problems after the death of a loved one. One issue that is still unexplored is the relative importance of these two concepts in predicting bereavement outcome. The current study examined the degree to which both concepts contribute to emotional distress after loss, both concurrently and longitudinally. Data were available from 124 individuals, all bereaved within the previous half year, who completed measures of prolonged grief, posttraumatic stress, and depression at inclusion into the study and again 6 months later. Loss-centrality and self-unclarity were associated with all three outcome measures, in cross-sectional analyses. Longitudinal analyses indicated that loss-centrality predicted symptom levels of prolonged grief, self-unclarity predicted symptom levels of depression, and both loss-centrality and self-unclarity were associated with posttraumatic stress 6 months after baseline. Implications of these findings are discussed.

Memory-Augmented Active Deep Learning for Identifying Relations Between Distant Medical Concepts in Electroencephalography Reports.

PubMed

Maldonado, Ramon; Goodwin, Travis R; Harabagiu, Sanda M

2018-01-01

The automatic identification of relations between medical concepts in a large corpus of Electroencephalography (EEG) reports is an important step in the development of an EEG-specific patient cohort retrieval system as well as in the acquisition of EEG-specific knowledge from this corpus. EEG-specific relations involve medical concepts that are not typically mentioned in the same sentence or even the same section of a report, thus requiring extraction techniques that can handle such long-distance dependencies. To address this challenge, we present a novel frame work which combines the advantages of a deep learning framework employing Dynamic Relational Memory (DRM) with active learning. While DRM enables the prediction of long-distance relations, active learning provides a mechanism for accurately identifying relations with minimal training data, obtaining an 5-fold cross validationF1 score of 0.7475 on a set of 140 EEG reports selected with active learning. The results obtained with our novel framework show great promise.

Use of various contraceptive methods and time of conception in a community-based population.

PubMed

Kaplan, Boris; Nahum, Ravit; Yairi, Yael; Hirsch, Michael; Pardo, Josef; Yogev, Yariv; Orvieto, Raoul

2005-11-01

To investigate the association between method of contraception and time to conception in a normal community-based population. Prospective, cross-sectional, survey. Large comprehensive ambulatory women's health center. One thousand pregnant women at their first prenatal obstetrics visit were asked to complete a self-report questionnaire. The return to fertility was analyzed by type of contraceptive method, duration of use, and other sociodemographic variables. Response rate was 80% (n=798). Mean age of the patients was 29.9+/-5 years. Seventy-five percent had used a contraceptive before trying to conceive: 80% oral contraceptives, 8% intrauterine device, and 7% barrier methods. Eighty-six percent conceived spontaneously. Contraceptive users had a significantly higher conception rate than nonusers in the first 3 months from their first attempt at pregnancy. Type of contraception was significantly correlated with time to conception. Pregnancy rates within 6 months of the first attempt was 60% for oral contraceptive users compared to 70 and 81% for the intrauterine device and barrier method groups, respectively. There was no correlation between time to conception and parity or duration of contraceptive use. Other factors found to be significantly related to time to conception were older age of both partners and higher body mass index. Contraception use before a planned pregnancy does not appear to affect ease of conception. Type of method used, although not duration of use, may influence the time required to conceive.

Neutron optics concept for the materials engineering diffractometer at the ESS

NASA Astrophysics Data System (ADS)

Šaroun, J.; Fenske, J.; Rouijaa, M.; Beran, P.; Navrátil, J.; Lukáš, P.; Schreyer, A.; Strobl, M.

2016-09-01

The Beamline for European Materials Engineering Research (BEER) has been recently proposed to be built at the European Spallation Source (ESS). The presented concept of neutron delivery optics for this instrument addresses the problems of bi-spectral beam extraction from a small moderator, optimization of neutron guides profile for long-range neutron transport and focusing at the sample under various constraints. They include free space before and after the guides, a narrow guide section with gaps for choppers, closing of direct line of sight and cost reduction by optimization of the guides cross-section and coating. A system of slits and exchangeable focusing optics is proposed in order to match various wavelength resolution options provided by the pulse shaping and modulation choppers, which permits to efficiently trade resolution for intensity in a wide range. Simulated performance characteristics such as brilliance transfer ratio are complemented by the analysis of the histories of “useful” neutrons obtained by back tracing neutrons hitting the sample, which helps to optimize some of the neutron guide parameters such as supermirror coating.

NanoVipa: a miniaturized high-resolution echelle spectrometer, for the monitoring of young stars from a 6U Cubesat

NASA Astrophysics Data System (ADS)

Bourdarot, G.; Le Coarer, E.; Bonfils, X.; Alecian, E.; Rabou, P.; Magnard, Y.

2017-12-01

We introduce to astrophysical instrumentation and space optics the use of virtually imaged phased array (VIPA) to shrink échelle spectrometers and/or increase their resolution. Here, we report on both a concept of an echelle spectrometer with resolution R=50{,}000 (@653nm), which fits a 6U nanosatellite platform ({{1U= 10 cm × 10 cm × 10 cm}}), and on our laboratory tests on a R=200{,}000 demonstrator. The outline of our paper is as follows: Sect. 1 introduces our concept of a 6U payload comprising an échelle spectrometer based on the VIPA. We present also the science cases of monitoring young stars, and the wider science landscape amenable with larger telescopes. Section 2 gives a more detailed description of the VIPA and of its implementation in a cross-dispersed spectrometer. Section 3 shows the first results at R=200{,}000 we already achieved at the Institut de Planétologie et d'Astrophysique de Grenoble (IPAG). Finally, Sect. 4 is a discussion on the remaining technical points to study.

Structure of the Balmer jump. The isolated hydrogen atom

NASA Astrophysics Data System (ADS)

Calvo, F.; Belluzzi, L.; Steiner, O.

2018-06-01

Context. The spectrum of the hydrogen atom was explained by Bohr more than one century ago. We revisit here some of the aspects of the underlying quantum structure, with a modern formalism, focusing on the limit of the Balmer series. Aims: We investigate the behaviour of the absorption coefficient of the isolated hydrogen atom in the neighbourhood of the Balmer limit. Methods: We analytically computed the total cross-section arising from bound-bound and bound-free transitions in the isolated hydrogen atom at the Balmer limit, and established a simplified semi-analytical model for the surroundings of that limit. We worked within the framework of the formalism of Landi Degl'Innocenti & Landolfi (2004, Astrophys. Space Sci. Lib., 307), which permits an almost straight-forward generalization of our results to other atoms and molecules, and which is perfectly suitable for including polarization phenomena in the problem. Results: We analytically show that there is no discontinuity at the Balmer limit, even though the concept of a "Balmer jump" is still meaningful. Furthermore, we give a possible definition of the location of the Balmer jump, and we check that this location is dependent on the broadening mechanisms. At the Balmer limit, we compute the cross-section in a fully analytical way. Conclusions: The Balmer jump is produced by a rapid drop of the total Balmer cross-section, yet this variation is smooth and continuous when both bound-bound and bound-free processes are taken into account, and its shape and location is dependent on the broadening mechanisms.

Vehicle-to-infrastructure rail crossing violation warning : concept of operations.

DOT National Transportation Integrated Search

2016-03-31

This Concept of Operations (ConOps) document describes the operational characteristics of a Vehicle-to-Infrastructure (V2I) Rail Crossing Violation Warning (RCVW) safety application. The development of this document was completed with an advisory tea...

Effects of anisotropic electron-ion interactions in atomic photoelectron angular distributions

NASA Technical Reports Server (NTRS)

Dill, D.; Starace, A. F.; Manson, S. T.

1975-01-01

A summary of the angular momentum transfer formulation of the differential photoionization cross section is presented and photoionization amplitudes in LS coupling are considered. The application of the theoretical concepts and relations developed is illustrated with the aid of an example involving the calculation of the angular distribution of photoelectrons ionized from atomic sulfur according to a certain reaction. The investigation shows that anisotropic electron-ion interactions in atomic sulfur lead to measurable differences between photoelectron angular distribution asymmetry parameters corresponding to alternative ionic term levels.

An ultra-high vacuum chamber for scattering experiments featuring in-vacuum continuous in-plane variation of the angle between entrance and exit vacuum ports

DOE Office of Scientific and Technical Information (OSTI.GOV)

Englund, Carl-Johan; Agåker, Marcus, E-mail: marcus.agaker@physics.uu.se; Fredriksson, Pierre

2015-09-15

A concept that enables in-vacuum continuous variation of the angle between two ports in one plane has been developed and implemented. The vacuum chamber allows for measuring scattering cross sections as a function of scattering angle and is intended for resonant inelastic X-ray scattering experiments. The angle between the ports can be varied in the range of 30°-150°, while the pressure change is less than 2 × 10{sup −10} mbars.

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.

Cross-Cultural Invariance of the Mental Toughness Inventory Among Australian, Chinese, and Malaysian Athletes: A Bayesian Estimation Approach.

PubMed

Gucciardi, Daniel F; Zhang, Chun-Qing; Ponnusamy, Vellapandian; Si, Gangyan; Stenling, Andreas

2016-04-01

The aims of this study were to assess the cross-cultural invariance of athletes' self-reports of mental toughness and to introduce and illustrate the application of approximate measurement invariance using Bayesian estimation for sport and exercise psychology scholars. Athletes from Australia (n = 353, Mage = 19.13, SD = 3.27, men = 161), China (n = 254, Mage = 17.82, SD = 2.28, men = 138), and Malaysia (n = 341, Mage = 19.13, SD = 3.27, men = 200) provided a cross-sectional snapshot of their mental toughness. The cross-cultural invariance of the mental toughness inventory in terms of (a) the factor structure (configural invariance), (b) factor loadings (metric invariance), and (c) item intercepts (scalar invariance) was tested using an approximate measurement framework with Bayesian estimation. Results indicated that approximate metric and scalar invariance was established. From a methodological standpoint, this study demonstrated the usefulness and flexibility of Bayesian estimation for single-sample and multigroup analyses of measurement instruments. Substantively, the current findings suggest that the measurement of mental toughness requires cultural adjustments to better capture the contextually salient (emic) aspects of this concept.

Potentially modifiable lifestyle factors, cognitive reserve, and cognitive function in later life: A cross-sectional study

PubMed Central

Wu, Yu-Tzu

2017-01-01

Background Potentially modifiable lifestyle factors may influence cognitive health in later life and offer potential to reduce the risk of cognitive decline and dementia. The concept of cognitive reserve has been proposed as a mechanism to explain individual differences in rates of cognitive decline, but its potential role as a mediating pathway has seldom been explored using data from large epidemiological studies. We explored the mediating effect of cognitive reserve on the cross-sectional association between lifestyle factors and cognitive function in later life using data from a population-based cohort of healthy older people. Methods and findings We analysed data from 2,315 cognitively healthy participants aged 65 y and over in the Cognitive Function and Ageing Study Wales (CFAS-Wales) cohort collected in 2011–2013. Linear regression modelling was used to investigate the overall associations between five lifestyle factors—cognitive and social activity, physical activity, diet, alcohol consumption, and smoking—and cognition, adjusting for demographic factors and chronic conditions. Mediation analysis tested for indirect effects of the lifestyle factors on cognition via cognitive reserve. After controlling for age, gender, and the presence of chronic conditions, cognitive and social activity, physical activity, healthy diet, and light-to-moderate alcohol consumption were positively associated with cognitive function, together accounting for 20% (95% CI 17%–23%) of variance in cognitive test scores. Cognitive reserve was an important mediator of this association, with indirect effects via cognitive reserve contributing 21% (95% CI 15%–27%) of the overall effect on cognition. The main limitations of the study derive from the cross-sectional nature of the data and the challenges of accurately measuring the latent construct of cognitive reserve. Conclusions Cross-sectional associations support the view that enhancing cognitive reserve may benefit cognition, and maintenance of cognitive health may be supported by a healthy and active lifestyle, in later life. PMID:28323829

Assessing Self-concept as a Mediator Between Anger and Resilience in Adolescents With Cancer in Taiwan.

PubMed

Wu, Wei-Wen; Chang, Joanne T; Tsai, Shao-Yu; Liang, Shu-Yuan

Anger is considered a common method used by patients to relieve emotional frustrations. However, this emotional response is not a common research focus for adolescents with cancer. The aim of this study was to determine whether self-concept mediated the relationship between anger and resilience for adolescent patients currently being treated for cancer. A cross-sectional study of 40 adolescents with cancer was conducted. The instruments included the Chinese Beck Self-Concept Inventory, the Chinese Beck Anger Inventory, and the Chinese Resilience Scale. Mediation analysis was also conducted. The results indicate that (1) variations in anger significantly account for 6.86% of observed variations in self-concept, (2) variations in self-concept significantly account for 52.83% of observed variations in resilience, (3) variations in anger significantly account for 10.96% of observed variations in resilience, and (4) when paths in conditions 1 and 2 were controlled, variations in anger through self-concept significantly account for 54.04% of observed variations in resilience, and variations in anger did not significantly account for observed variations in resilience. Gender and age might affect anger control. Despite worse physical functioning and an impacted appearance, participants had normative-to-positive self-concept levels, suggesting that their self-concept might not be affected by cancer. Self-concept might play a mediating role between anger and resilience, thus helping to bridge this knowledge gap. The current gap in knowledge regarding the mediating relationship necessitates the implementation of a large-scale study designed to verify the mediating role of self-concept between anger and resilience.

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.

Buddhist concepts as implicitly reducing prejudice and increasing prosociality.

PubMed

Clobert, Magali; Saroglou, Vassilis; Hwang, Kwang-Kuo

2015-04-01

Does Buddhism really promote tolerance? Based on cross-cultural and cross-religious evidence, we hypothesized that Buddhist concepts, possibly differing from Christian concepts, activate not only prosociality but also tolerance. Subliminally priming Buddhist concepts, compared with neutral or Christian concepts, decreased explicit prejudice against ethnic, ideological, and moral outgroups among Western Buddhists who valued universalism (Experiment 1, N = 116). It also increased spontaneous prosociality, and decreased, among low authoritarians or high universalists, implicit religious and ethnic prejudice among Westerners of Christian background (Experiment 2, N = 128) and Taiwanese of Buddhist/Taoist background (Experiment 3, N = 122). Increased compassion and tolerance of contradiction occasionally mediated some of the effects. The general idea that religion promotes (ingroup) prosociality and outgroup prejudice, based on research in monotheistic contexts, lacks cross-cultural sensitivity; Buddhist concepts activate extended prosociality and tolerance of outgroups, at least among those with socio-cognitive and moral openness. © 2015 by the Society for Personality and Social Psychology, Inc.

A comparison of response rates in the English Longitudinal Study of Ageing and the Health and Retirement Study

PubMed Central

Cheshire, Hayley; Ofstedal, Mary Beth; Scholes, Shaun; Schroeder, Mathis

2013-01-01

Survey response rates are an important measure of the quality of a survey; this is true for both longitudinal and cross-sectional surveys. However, the concept of a response rate in the context of a panel survey is more complex than is the case for a cross-sectional survey. There are typically many different response rates that can be calculated for a panel survey, each of which may be relevant for a specific purpose. The main objective of our paper is to document and compare response rates for two long-term panel studies of ageing, the English Longitudinal Study of Ageing (ELSA) and the Health and Retirement Study (HRS) in the United States. To guide our selection and calculation of response rates for the two studies, we use a framework that was developed by Peter Lynn (2005) and present several different types of longitudinal response rates for the two surveys. We discuss similarities and differences in the study designs and protocols and how some of the differences affect comparisons of response rates across the two studies. PMID:24432049

Knowledge and attitude towards organ donation of medicine students of a Northwestern Mexico public university

PubMed

Sebastián-Ruiz, María José; Guerra-Sáenz, Elda Karina; Vargas-Yamanaka, Anna Karen; Barboza-Quintana, Oralia; Ríos-Zambudio, Antonio; García-Cabello, Ricardo; Palacios-Saucedo, Gerardo Del Carmen

2017-01-01

To evaluate the knowledge and attitude towards organ donation of medicine students of a Northwestern Mexico public university. A prolective, descriptive, observational, and cross-sectional study. A 34 items cross-sectional survey evaluating knowledge and attitude towards organ donation in 3,056 medicine students during 2013-2015. Descriptive statistics were used as absolute frequencies, percentages, mean and standard deviation, as well as the Chi-square test. A p < 0.05 was considered significant. 74% of students would donate their own organs, mainly due to reciprocity (41%). 26% of students would not donate, 48% of them because of fear that their organs could be taken before death. 86% would donate organs from a relative. 64% have spoken about organ donation and transplantation with their family and 67% with friends. 50% said they had received no information about it. 68% understand the concept of brain death. Students received little information about organ donation during college. Despite that, most of them showed a positive attitude and are willing to donate. Copyright: © 2017 SecretarÍa de Salud

How to measure a complete set of polarization-dependent differential cross sections in a scattering experiment with aligned reagents?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Fengyan, E-mail: fengyanwang@fudan.edu.cn, E-mail: kliu@po.iams.sinica.edu.tw; Department of Chemistry, Fudan University, Shanghai 200433; Lin, Jui-San

2014-02-28

Polarization-dependent differential cross section (PDDCS) is one of the three-vector correlations (k, k{sup ′}, j) in molecular collisions, which provides the most detailed insights into the steric requirements of chemical reactions, i.e., how the reactivity depends on the polarization of reagents. Only quite recently has such quantity been fully realized experimentally in the study of the reaction of the aligned CHD{sub 3}(v{sub 1} = 1, |jK〉 = |10〉) molecules with Cl({sup 2}P{sub 3/2}) atoms. Theoretically, PDDCS is a relatively new concept; experimental realization of the theoretical construct requires some careful considerations that are not readily available in the literature. Here,more » we present the “know-how” behind the full PDDCS measurements to fill the gaps and to provide a clear roadmap for future applications. To make the connection apparent between the methodology presented here and the stereodynamics revealed in previous reports, the same Cl + aligned CHD{sub 3} reaction is used for illustration.« less

Household disrepair and the mental health of low-income urban women.

PubMed

Burdette, Amy M; Hill, Terrence D; Hale, Lauren

2011-02-01

We employ longitudinal survey data from the Welfare, Children, and Families project (1999, 2001) to examine the effects of household disrepair (e.g., living with leaky structures, busted plumbing, broken windows, and pests) on psychological distress among low-income urban women with children. Building on previous research, we adjust for related housing concepts, neighborhood disorder, financial hardship, and a host of relevant background factors. We also formally test the mediating influences of social support and self-esteem. Our cross-sectional analysis indicated that household disrepair is positively associated with recent symptoms of psychological distress. Our longitudinal change score analysis demonstrates two important patterns. First, women living with household disrepair at baseline are not necessarily vulnerable to increases in symptoms of psychological distress over the 2-year study period. Second, women who report an increase in disrepair over the study period are also likely to report a concurrent increase in symptoms of distress. Although social support and self-esteem favor mental health in our cross-sectional and longitudinal analyses, these psychosocial resources fail to mediate or explain the association between disrepair and distress.

A Rigid Mid-Lift-to-Drag Ratio Approach to Human Mars Entry, Descent, and Landing

NASA Technical Reports Server (NTRS)

Cerimele, Christopher J.; Robertson, Edward A.; Sostaric, Ronald R.; Campbell, Charles H.; Robinson, Phil; Matz, Daniel A.; Johnson, Breanna J.; Stachowiak, Susan J.; Garcia, Joseph A.; Bowles, Jeffrey V.;

Bessel Weighted Asymmetries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Avakian, Harut; Gamberg, Leonard; Rossi, Patrizia

We review the concept of Bessel weighted asymmetries for semi-inclusive deep inelastic scattering and focus on the cross section in Fourier space, conjugate to the outgoing hadron’s transverse momentum, where convolutions of transverse momentum dependent parton distribution functions and fragmentation functions become simple products. Individual asymmetric terms in the cross section can be projected out by means of a generalized set of weights involving Bessel functions. The procedure is applied to studies of the double longitudinal spin asymmetry in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator which includes quark intrinsic transverse momentum within the generalized partonmore » model. We observe a few percent systematic offset of the Bessel-weighted asymmetry obtained from Monte Carlo extraction compared to input model calculations, which is due to the limitations imposed by the energy and momentum conservation at the given energy and hard scale Q2. We find that the Bessel weighting technique provides a powerful and reliable tool to study the Fourier transform of TMDs with controlled systematics due to experimental acceptances and resolutions with different TMD model inputs.« less

Influence of nuclear basic data on the calculation of production cross sections of superheavy nuclei

NASA Astrophysics Data System (ADS)

Bao, X. J.; Gao, Y.; Li, J. Q.; Zhang, H. F.

2015-07-01

The center of the predicted island of stability of superheavy nuclei (SHN) has not yet been observed experimentally. Many theories are being developed to understand the synthesizing mechanism of superheavy nuclei. However, all of them have to use some basic nuclear data. Three data tables, FRDM1995 [P. Möller et al., At. Data Nucl. Data Tables 59, 185 (1995), 10.1006/adnd.1995.1002], KTUY2005 [H. Koura et al., Prog. Theor. Phys. 113, 305 (2005), 10.1143/PTP.113.305], and WS2010 [Ning Wang et al., Phys. Rev. C 82, 044304 (2010), 10.1103/PhysRevC.82.044304], are used to investigate the SHN production. Based on the dinuclear system concept, the evaporation residue cross sections of SHN for Z =112-118 are calculated for the 48Ca -induced hot fusion reactions. It turns out that unlike the predictions made with the KTUY2005 and WS2010 data, the magic numbers Z =114 and N =184 predicted with the FRDM1995 data do not contradict the experimental data obtained so far.

On Flexible Tubes Conveying Fluid: Geometric Nonlinear Theory, Stability and Dynamics

NASA Astrophysics Data System (ADS)

Gay-Balmaz, François; Putkaradze, Vakhtang

2015-08-01

We derive a fully three-dimensional, geometrically exact theory for flexible tubes conveying fluid. The theory also incorporates the change of the cross section available to the fluid motion during the dynamics. Our approach is based on the symmetry-reduced, exact geometric description for elastic rods, coupled with the fluid transport and subject to the volume conservation constraint for the fluid. We first derive the equations of motion directly, by using an Euler-Poincaré variational principle. We then justify this derivation with a more general theory elucidating the interesting mathematical concepts appearing in this problem, such as partial left (elastic) and right (fluid) invariance of the system, with the added holonomic constraint (volume). We analyze the fully nonlinear behavior of the model when the axis of the tube remains straight. We then proceed to the linear stability analysis and show that our theory introduces important corrections to previously derived results, both in the consistency at all wavelength and in the effects arising from the dynamical change of the cross section. Finally, we derive and analyze several analytical, fully nonlinear solutions of traveling wave type in two dimensions.

Behavioral self-concept as predictor of teen drinking behaviors.

PubMed

Dudovitz, Rebecca N; Li, Ning; Chung, Paul J

2013-01-01

Adolescence is a critical developmental period for self-concept (role identity). Cross-sectional studies link self-concept's behavioral conduct domain (whether teens perceive themselves as delinquent) with adolescent substance use. If self-concept actually drives substance use, then it may be an important target for intervention. In this study, we used longitudinal data from 1 school year to examine whether behavioral self-concept predicts teen drinking behaviors or vice versa. A total of 291 students from a large, predominantly Latino public high school completed a confidential computerized survey in the fall and spring of their 9th grade year. Survey measures included the frequency of alcohol use, binge drinking and at-school alcohol use in the previous 30 days; and the Harter Self-Perception Profile for Adolescents behavioral conduct subscale. Multiple regressions were performed to test whether fall self-concept predicted the frequency and type of spring drinking behavior, and whether the frequency and type of fall drinking predicted spring self-concept. Fall behavioral self-concept predicted both the frequency and type of spring drinking. Students with low versus high fall self-concept had a predicted probability of 31% versus 20% for any drinking, 20% versus 8% for binge drinking and 14% versus 4% for at-school drinking in the spring. However, neither the frequency nor the type of fall drinking significantly predicted spring self-concept. Low behavioral self-concept may precede or perhaps even drive adolescent drinking. If these results are confirmed, then prevention efforts might be enhanced by targeting high-risk teens for interventions that help develop a healthy behavioral self-concept. Copyright © 2013 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.

Reducing cross-sectional data using a genetic algorithm method and effects on cross-section geometry and steady-flow profiles

USGS Publications Warehouse

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.

An optimized top contact design for solar cell concentrators

NASA Technical Reports Server (NTRS)

Desalvo, Gregory C.; Barnett, Allen M.

1985-01-01

A new grid optimization scheme is developed for point focus solar cell concentrators which employs a separated grid and busbar concept. Ideally, grid lines act as the primary current collectors and receive all of the current from the semiconductor region. Busbars are the secondary collectors which pick up current from the grids and carry it out of the active region of the solar cell. This separation of functions leads to a multithickness metallization design, where the busbars are made larger in cross section than the grids. This enables the busbars to carry more current per unit area of shading, which is advantageous under high solar concentration where large current densities are generated. Optimized grid patterns using this multilayer concept can provide a 1.6 to 20 percent increase in output power efficiency over optimized single thickness grids.

PRISM Spectrograph Optical Design

NASA Technical Reports Server (NTRS)

Chipman, Russell A.

1995-01-01

The objective of this contract is to explore optical design concepts for the PRISM spectrograph and produce a preliminary optical design. An exciting optical configuration has been developed which will allow both wavelength bands to be imaged onto the same detector array. At present the optical design is only partially complete because PRISM will require a fairly elaborate optical system to meet its specification for throughput (area*solid angle). The most complex part of the design, the spectrograph camera, is complete, providing proof of principle that a feasible design is attainable. This camera requires 3 aspheric mirrors to fit inside the 20x60 cm cross-section package. A complete design with reduced throughput (1/9th) has been prepared. The design documents the optical configuration concept. A suitable dispersing prism material, CdTe, has been identified for the prism spectrograph, after a comparison of many materials.

Facies in stratigraphy: from 'terrains' to 'terranes'.

USGS Publications Warehouse

Nelson, C.M.

1985-01-01

Concepts of lateral variation in sedimentary rocks and fossil assemblages developed in France from the 1760s; the definitive definition of facies was provided in 1838 by the Swiss geologist Amanz Gressly (1814-65) in his detailed field study of the eastern Jura. His maps and cross-sections of variations in Jurassic and Triassic rocks are illustrated. He believed that variations reflected environmental conditions, as in modern seas, and would eventually permit former depths to be reconstructed. Gressly studied at Strasbourg under Voltz and Thurmann: he collaborated with L.Agassiz, E.Desor and C.Vogt. His work influenced German and French geologists and provided a basis for interpretations of the Alps. But the facies concept was not deeply rooted in American geology until around 1884 (H.S.Williams) and in Britain and Russia until around 1900. I.S.Evans

Knowledge about conception, sexual behavior, and procurement of abortion among female undergraduate students in a Nigerian university.

PubMed

Moronkola, O A; Amosu, A; Okonkwo, C

Of 1,200 questionnaires administered in a cross-sectional study involving University of Ibadan female students, 1000 were found useable for data analysis. Analysis found that a majority of respondents (56.4%) had little knowledge about conception and frequently engaged in sexual intercourse for many reasons, including: to have fun; to show they were mature; and to seek material reward. Also, 61.1% had procured abortion before and most of them did not procure it from government-owned hospitals/clinics, which may likely make them prone to health consequences of unsafe abortion. Part of our recommendations are the need to introduce health education (incorporating sexuality education) into the General Studies Program of the university and that home training on aspects relating to sexuality education be given to and promoted among young people.

The relative effects of entry parameters on thermal protection system weight. [space shuttle orbiters

NASA Technical Reports Server (NTRS)

Hirasaki, P. N.

1971-01-01

Shielding a spacecraft from the severe thermal environment of an atmospheric entry requires a sophisticated thermal protection system (TPS). Thermal computer program models were developed for two such TPS designs proposed for the space shuttle orbiter. The multilayer systems, a reusable surface insulation TPS, and a re-radiative metallic skin TPS, were sized for a cross-section of trajectories in the entry corridor. This analysis indicates the relative influence of the entry parameters on the weight of each TPS concept. The results are summarized graphically. The trajectory variables considered were down-range, cross-range, orbit inclination, entry interface velocity and flight path angle, maximum heating rate level, angle of attack, and ballistic coefficient. Variations in cross-range and flight path angle over the ranges considered had virtually no effect on the required entry TPS weight. The TPS weight was significantly more sensitive to variations in angle of attack than to dispersions in the other trajectory considered.

Load-Direction-Derived Support Structures for Wind Turbines: A Lattice Tower Concept and Preparations for Future Certifications: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jonkman, Jason; Damiani, Rick R; Struve, Achim

The call for more cost-effective and environmentally friendly tower concepts is motivated by tower costs [1] and tower CO2-emission contributions [2], which are high relative to the whole wind turbine system. The proposed rotatable tower concept with yaw bearing at the bottom instead of the top of the tower will provide beneficial economic and environmental impacts to the turbine system. This wind alignment capability indicates a load-direction-derived tower design. By combining this approach with a lattice concept, large material and cost savings for the tower can be achieved. This paper presents a way to analyze and verify the proposed designmore » through aero-servo-elastic simulations, which make future certifications of rotatable tower concepts viable. For this reason, the state-of-the-art, open-source lattice-tower finite-element-method (FEM) module SubDyn [10], developed by the National Renewable Energy Laboratory, has been modified to account for arbitrary member cross-sections. Required changes in the beam element stiffness and mass matrix formulation took place according to an energy method [13]. All validated adaptions will be usable within the aero-servo-elastic simulation framework FAST and are also beneficial for other nonrotatable lattice structures.« less

Developing Intercultural Adaptability in the Warfighter: A Workshop on Cultural Training and Education

DTIC Science & Technology

2010-11-01

operational culture ” concept and teaching of interpersonal skills in advisor training, but emphasizes regional studies both in its pre-deployment...experts and non-experts. Building on earlier discussions, the group focused on the concept of cross- cultural competence and debated whether it is...For skills, the goal is to understand general regional concepts (not region-specific facts) and to develop confidence through cross- cultural

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.

Patients’ Dignity and Its Relationship with Contextual Variables: A Cross-Sectional Study

PubMed Central

Zirak, Mohammad; Ghafourifard, Mansour; Aliafsari Mamaghani, Ebrahim

2017-01-01

Introduction: Dignity is considered as fundamental human needs and recognized as one of the central concepts in nursing science. The aim of this study was to assess the extent to which patients’ dignity is respected and to evalutae its relationship with contextual variables. Methods: This cross-sectional study was conducted on 256 hospitalized patients in the two teaching hospitals affiliated to Zanjan University of medical sciences, Iran. Data were collected by a questionnaire consist of two sections: (a) demographic characteristics, and (b) patient dignity including 32 questions. Data were analyzed by SPSS (ver.13) software using independent t-test, ANOVA and Pearson correlation. Results: The result showed that the mean (standard deviation) of total score of patient’s dignity was 108.17 (25.28). According to the result, the majority of the respondents (76.2%) were not aware of patient’s rights. There was a significant difference in mean scores of total dignity between single and married persons, living in city or village, and hospitalization in Moosavi and Valiasr hospital. Conclusion: Health care systems should take the provision of the patients' dignity into account through using a comprehensive educational program for informing of patient, family members, and health professionals about patients’ dignity. PMID:28299297

Students' Energy Concepts at the Transition Between Primary and Secondary School

NASA Astrophysics Data System (ADS)

Opitz, Sebastian T.; Harms, Ute; Neumann, Knut; Kowalzik, Kristin; Frank, Arne

2015-10-01

Energy is considered both a core idea and a crosscutting concept in science education. A thorough understanding of the energy concept is thought to help students learn about other (related) concepts within and across science subjects, thereby fostering scientific literacy. This study investigates students' progression in understanding the energy concept in biological contexts at the transition from primary to lower secondary school by employing a quantitative, cross-sectional study in grades 3-6 ( N = 540) using complex multiple-choice items. Based on a model developed in a previous study, energy concepts were assessed along four aspects of energy: (1) forms and sources of energy, (2) transfer and transformation, (3) degradation and dissipation, and (4) energy conservation. Two parallel test forms (A and B) indicated energy concept scores to increase significantly by a factor of 2.3 (A)/1.7 (B) from grade 3 to grade 6. Students were observed to progress in their understanding of all four aspects of the concept and scored highest on items for energy forms. The lowest scores and the smallest gain across grades were found for energy conservation. Based on our results, we argue that despite numerous learning opportunities, students lack a more integrated understanding of energy at this stage, underlining the requirement of a more explicit approach to teaching energy to young learners. Likewise, more interdisciplinary links for energy learning between relevant contexts in each science discipline may enable older students to more efficiently use energy as a tool and crosscutting concept with which to analyze complex content.

[Cultural conceptions on dengue in urban contexts in Mexico].

PubMed

Caballero Hoyos, Ramiro; Torres López, Teresa; Chong Villarreal, Francisco; Pineda Lucatero, Alicia; Altuzar González, Marlene; López Coutiño, Berenice

2006-02-01

To explore the conceptual dimensions of dengue in the urban context, aiming at creating hypotheses about community attitudes toward prevention campaigns. An exploratory cross-sectional study was carried out between March and April 2003 comprising 130 people selected by proposition sampling in three municipalities with different dengue prevalences in Mexico. Semi-structured interviews were applied using free lists, pile sorts and triads. Dengue-related terms and groups of conceptual dimensions were investigated. A consensual analysis was performed by factorizing the major components as well as a dimensional analysis with hierarchical clustering and multidimensional scales. The consensual model showed high homogeneity in dengue conceptions (values of 14.5 and 13.5 in the most prevalent contexts, and 5.4 in the least prevalent one). The common dimensions of conceptions were: preventive measures, symptoms, causes and reservoirs of Aedes aegypti (goodness of fit test values: <0.28). In the three contexts studied, a conception of basic prevention based on public actions by health officials predominated while individual and community actions were almost never mentioned. A moral dimension also appeared in the conception based on a notion of hygiene as a differentiating mechanism between the nearby community (clean) and outside people and communities (dirty and sick). The cultural conceptions of dengue do not favor self-managed community involvement in vertical prevention campaigns, and create obstacles to modifying community and individual prevention and control practices.

Nano-Computed Tomography: Technique and Applications.

PubMed

Kampschulte, M; Langheinirch, A C; Sender, J; Litzlbauer, H D; Althöhn, U; Schwab, J D; Alejandre-Lafont, E; Martels, G; Krombach, G A

2016-02-01

Nano-computed tomography (nano-CT) is an emerging, high-resolution cross-sectional imaging technique and represents a technical advancement of the established micro-CT technology. Based on the application of a transmission target X-ray tube, the focal spot size can be decreased down to diameters less than 400 nanometers (nm). Together with specific detectors and examination protocols, a superior spatial resolution up to 400 nm (10 % MTF) can be achieved, thereby exceeding the resolution capacity of typical micro-CT systems. The technical concept of nano-CT imaging as well as the basics of specimen preparation are demonstrated exemplarily. Characteristics of atherosclerotic plaques (intraplaque hemorrhage and calcifications) in a murine model of atherosclerosis (ApoE (-/-)/LDLR(-/-) double knockout mouse) are demonstrated in the context of superior spatial resolution in comparison to micro-CT. Furthermore, this article presents the application of nano-CT for imaging cerebral microcirculation (murine), lung structures (porcine), and trabecular microstructure (ovine) in contrast to micro-CT imaging. This review shows the potential of nano-CT as a radiological method in biomedical basic research and discusses the application of experimental, high resolution CT techniques in consideration of other high resolution cross-sectional imaging techniques. Nano-computed tomography is a high resolution CT-technology for 3D imaging at sub-micrometer resolution. The technical concept bases on a further development of the established ex-vivo-micro-CT technology. By improvement of the spatial resolution, structures at a cellular level become visible (e.g. osteocyte lacunae). © Georg Thieme Verlag KG Stuttgart · New York.

Simultaneous one-dimensional fluorescence lifetime measurements of OH and CO in premixed flames

NASA Astrophysics Data System (ADS)

Jonsson, Malin; Ehn, Andreas; Christensen, Moah; Aldén, Marcus; Bood, Joakim

2014-04-01

A method for simultaneous measurements of fluorescence lifetimes of two species along a line is described. The experimental setup is based on picosecond laser pulses from two tunable optical parametric generator/optical parametric amplifier systems together with a streak camera. With an appropriate optical time delay between the two laser pulses, whose wavelengths are tuned to excite two different species, laser-induced fluorescence can be both detected temporally and spatially resolved by the streak camera. Hence, our method enables one-dimensional imaging of fluorescence lifetimes of two species in the same streak camera recording. The concept is demonstrated for fluorescence lifetime measurements of CO and OH in a laminar methane/air flame on a Bunsen-type burner. Measurements were taken in flames with four different equivalence ratios, namely ϕ = 0.9, 1.0, 1.15, and 1.25. The measured one-dimensional lifetime profiles generally agree well with lifetimes calculated from quenching cross sections found in the literature and quencher concentrations predicted by the GRI 3.0 mechanism. For OH, there is a systematic deviation of approximately 30 % between calculated and measured lifetimes. It is found that this is mainly due to the adiabatic assumption regarding the flame and uncertainty in H2O quenching cross section. This emphasizes the strength of measuring the quenching rates rather than relying on models. The measurement concept might be useful for single-shot measurements of fluorescence lifetimes of several species pairs of vital importance in combustion processes, hence allowing fluorescence signals to be corrected for quenching and ultimately yield quantitative concentration profiles.

A cross-sectional study of chiropractic students' research readiness using the Academic Self-Concept Analysis Scale

PubMed Central

Whillier, Stephney; Au, Kent; Feng, Louie; Su, Helen

2017-01-01

Objective: The shift toward evidence-based health care has reoriented tertiary clinical education in a way that necessitates and incorporates research. This study assesses the inclination and suitability of chiropractic students for research over a 5-year educational program. Methods: Research attributes of chiropractic students were assessed in this cross-sectional study using a validated and modified academic self-concept analysis scale. Students in first and final year were assessed in 4 domains: creativity, motivation, self-regulation, and general intellectual ability. Univariable differences were assessed using Welch 2-sample t tests, and multivariable analysis was carried out with multiple linear regression models. Results: The response rate was 71% (n = 165). First- and fifth-year students scored highly on all 4 domains (80% to 96%). Compared to first-year students, fifth-year students rated themselves significantly lower in 3 of the domains: general intellectual abilities (t[126] = −2.01; p = 0.047), motivation (t[115] = −4.82; p < 0.001), and creativity (t[136] = −3.00; p = 0.003). Conclusion: Research suitability is high in chiropractic students. Both cohorts scored high in all domains despite the disparity between first and fifth years. First-year students outperformed fifth-year students in 3 domains, indicating a potential decline in the inclination to do research over time. However, unaccounted factors, such as the Dunning-Kruger effect, life changes, and “burnout,” may have contributed to these differences. Future studies should include questions about stress, fatigue, clinical orientation, and educational environment to inform the interpretation of findings. PMID:28768108

Visible Geology - Interactive online geologic block modelling

NASA Astrophysics Data System (ADS)

Cockett, R.

2012-12-01

Geology is a highly visual science, and many disciplines require spatial awareness and manipulation. For example, interpreting cross-sections, geologic maps, or plotting data on a stereonet all require various levels of spatial abilities. These skills are often not focused on in undergraduate geoscience curricula and many students struggle with spatial relations, manipulations, and penetrative abilities (e.g. Titus & Horsman, 2009). A newly developed program, Visible Geology, allows for students to be introduced to many geologic concepts and spatial skills in a virtual environment. Visible Geology is a web-based, three-dimensional environment where students can create and interrogate their own geologic block models. The program begins with a blank model, users then add geologic beds (with custom thickness and color) and can add geologic deformation events like tilting, folding, and faulting. Additionally, simple intrusive dikes can be modelled, as well as unconformities. Students can also explore the interaction of geology with topography by drawing elevation contours to produce their own topographic models. Students can not only spatially manipulate their model, but can create cross-sections and boreholes to practice their visual penetrative abilities. Visible Geology is easy to access and use, with no downloads required, so it can be incorporated into current, paper-based, lab activities. Sample learning activities are being developed that target introductory and structural geology curricula with learning objectives such as relative geologic history, fault characterization, apparent dip and thickness, interference folding, and stereonet interpretation. Visible Geology provides a richly interactive, and immersive environment for students to explore geologic concepts and practice their spatial skills.; Screenshot of Visible Geology showing folding and faulting interactions on a ridge topography.

A computer program for analyzing channel geometry

USGS Publications Warehouse

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)

Leading edge embedded fan airfoil concept -- A new powered high lift technology

NASA Astrophysics Data System (ADS)

Phan, Nhan Huu

A new powered-lift airfoil concept called Leading Edge Embedded Fan (LEEF) is proposed for Extremely Short Take-Off and Landing (ESTOL) and Vertical Take-Off and Landing (VTOL) applications. The LEEF airfoil concept is a powered-lift airfoil concept capable of generating thrust and very high lift-coefficient at extreme angles-of attack (AoA). It is designed to activate only at the take-off and landing phases, similar to conventional flaps or slats, allowing the aircraft to operate efficiently at cruise in its conventional configuration. The LEEF concept consists of placing a crossflow fan (CFF) along the leading-edge (LE) of the wing, and the housing is designed to alter the airfoil shape between take-off/landing and cruise configurations with ease. The unique rectangular cross section of the crossflow fan allows for its ease of integration into a conventional subsonic wing. This technology is developed for ESTOL aircraft applications and is most effectively applied to General Aviation (GA) aircraft. Another potential area of application for LEEF is tiltrotor aircraft. Unlike existing powered high-lift systems, the LEEF airfoil uses a local high-pressure air source from cross-flow fans, does not require ducting, and is able to be deployed using distributed electric power systems throughout the wing. In addition to distributed lift augmentation, the LEEF system can provide additional thrust during takeoff and landing operation to supplement the primary cruise propulsion system. Two-dimensional (2D) and three-dimensional (3D) Computational Fluid Dynamics (CFD) simulations of a conventional airfoil/wing using the NACA 63-3-418 section, commonly used in GA, and a LEEF airfoil/wing embedded into the same airfoil section were carried out to evaluate the advantages of and the costs associated with implementing the LEEF concept. Computational results show that significant lift and augmented thrust are available during LEEF operation while requiring only moderate fan power input. The CFD results show that airfoil circulation control is achieved by the varying the CFF intake flow rate and the momentum of the CFF exhaust jet (e.g. through airfoil AoA or fan rotational speed). The presence of the CFF has the effect of moving the stagnation point on the airfoil pressure surface from the CFF airfoil LE region near the CFF to as far back as the airfoil trailing edge. At high AoA operation, LE flow separation on the airfoil suction surface is delayed by flow entrainment of the high-energy jet leaving the CFF. Detailed analysis of the flow field through the crossflow fan and its housing were carried out to understand its fluid-dynamics behavior, and it is found that the airfoil geometry acts as inlet guide vanes to the crossflow fan as the angle-of-attack is varied, thus introducing pre-swirl or co-swirl into the first stage of the crossflow fan. An experimental study of the LEEF concept confirmed that the concept works and it is robust. Finally, as application examples, the LEEF technology is applied to a Remote Control model and to a generic tiltrotor aircraft similar in characteristics to DARPA's Aerial Reconfigurable Embedded System. These aircraft configurations were analyzed using 2D and 3D CFD.

Multistrand superconductor cable

DOEpatents

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

Dimensions and profiles of the generalized health-related self-concept.

PubMed

Wiesmann, Ulrich; Niehörster, Gabriele; Hannich, Hans-Joachim; Hartmann, Ute

2008-11-01

We explore the significance of health as a potentially self-relevant category from the perspective of dynamic self-concept theory. Our intention was to describe the dimensional structure of the generalized health-related self-concept, to identify particular prototypes of health-related self-definition, and to see if these prototypes would differ with respect to appraisals of health behaviour and subjective health. We conducted a cross-sectional questionnaire study involving 545 college students (23.3% male) at the mean age of 22 years. The self-administered questionnaire assessed a relevant spectrum of health-related cognitions denoting their generalized declarative knowledge about their health (the generalized health-related self-concept). Additionally, participants rated their multiple health behaviour, their perceived health, and their anticipated vulnerability. A principal components analysis of the health-related cognitions revealed the following five dimensions: health-protective dispositions, health-protective motivation, vulnerability, health-risky habits, and external, avoidant motivation. A two-step cluster analysis of the five components identified six profiles of health-related self-concept: careless/carefree, omnipotents, risk-takers, mentally affected, reluctant-avoidant, and medically fragile. These prototypes could be successfully reclassified (97.6%). The six profiles differed with respect to their health behaviour and subjective health appraisals. The dimensional structure represents both resources and deficits with respect to an individual's health-related self-concept. An individual's profile of these dimensions might correspond to a characteristic set of particular health needs and motivations. Successful health communications should follow a complementary strategy of affirming the self-concept.

Relationships among sexual self-concept and sexual risk cognition toward sexual self-efficacy in adolescents: cause-and-effect model testing.

PubMed

Hsu, Hsiu-Yueh; Yu, Hsing-Yi; Lou, Jiunn-Horng; Eng, Cheng-Joo

2015-04-01

Sexual self-efficacy plays an important role in adolescents' sexual health. The aim of this study was to test a cause-and-effect model of sexual self-concept and sexual risk cognition toward sexual self-efficacy in adolescents. The study was a cross-sectional survey. Using a random sampling method, a total of 713 junior nursing students were invited to participate in the study, and 465 valid surveys were returned, resulting in a return rate of 65.2%. The data was collected using an anonymous mailed questionnaire. Structural equation modeling was used to test the relationships among sexual self-concept, sexual risk cognition, and sexual self-efficacy, as well as the mediating role of sexual risk cognition. The results revealed that the postulated model fits the data well. Sexual self-concept significantly predicted sexual risk cognition and sexual self-efficacy. Sexual risk cognition significantly predicted sexual self-efficacy and had a mediating effect on the relationship between sexual self-concept and sexual self-efficacy. Based on social cognitive theory and a structural equation model technique, this study confirmed the mediating role of sexual risk cognition in the relationship between sexual self-concept and sexual self-efficacy. Also, sexual self-concept's direct and indirect effects explaining adolescents' sexual self-efficacy were found in this study. © 2014 The Authors. Japan Journal of Nursing Science © 2014 Japan Academy of Nursing Science.

Ion dipole capture cross sections at low ion and rotational energies - Comparison of integrated capture cross sections with reaction cross sections for NH3 and H2O parent-ion collisions.

NASA Technical Reports Server (NTRS)

Dugan, J. V., Jr.; Canright, R. B., Jr.

1972-01-01

The numerical capture cross section is calculated from the capture ratio, defined as the fraction of trajectories reaching a prescribed minimum separation of 3 A. The calculated capture cross sections for a rotational temperature of 77 K suggest large reaction cross sections in 80 K experiments for the large dipole-moment target, methyl cyanide.

Cultural differences in survey responding: Issues and insights in the study of response biases.

PubMed

Kemmelmeier, Markus

2016-12-01

This paper introduces the special section "Cultural differences in questionnaire responding" and discusses central topics in the research on response biases in cross-cultural survey research. Based on current conceptions of acquiescent, extreme, and socially desirable responding, the author considers current data on the correlated nature of response biases and the conditions under which different response styles they emerge. Based on evidence relating different response styles to the cultural dimension of individualism-collectivism, the paper explores how research presented as part of this special section might help resolves some tensions in this literature. The paper concludes by arguing that response styles should not be treated merely as measurement error, but as cultural behaviors in themselves. © 2016 International Union of Psychological Science.

Sex- and age-related differences in mid-thigh composition and muscle quality determined by computed tomography in middle-aged and elderly Japanese.

PubMed

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.

Statistical uncertainty analysis applied to the DRAGONv4 code lattice calculations and based on JENDL-4 covariance data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hernandez-Solis, A.; Demaziere, C.; Ekberg, C.

2012-07-01

In this paper, multi-group microscopic cross-section uncertainty is propagated through the DRAGON (Version 4) lattice code, in order to perform uncertainty analysis on k{infinity} and 2-group homogenized macroscopic cross-sections predictions. A statistical methodology is employed for such purposes, where cross-sections of certain isotopes of various elements belonging to the 172 groups DRAGLIB library format, are considered as normal random variables. This library is based on JENDL-4 data, because JENDL-4 contains the largest amount of isotopic covariance matrixes among the different major nuclear data libraries. The aim is to propagate multi-group nuclide uncertainty by running the DRAGONv4 code 500 times, andmore » to assess the output uncertainty of a test case corresponding to a 17 x 17 PWR fuel assembly segment without poison. The chosen sampling strategy for the current study is Latin Hypercube Sampling (LHS). The quasi-random LHS allows a much better coverage of the input uncertainties than simple random sampling (SRS) because it densely stratifies across the range of each input probability distribution. Output uncertainty assessment is based on the tolerance limits concept, where the sample formed by the code calculations infers to cover 95% of the output population with at least a 95% of confidence. This analysis is the first attempt to propagate parameter uncertainties of modern multi-group libraries, which are used to feed advanced lattice codes that perform state of the art resonant self-shielding calculations such as DRAGONv4. (authors)« less

Preliminary Structural Design Considerations and Mass Efficiencies for Lunar Surface Manipulator Concepts

NASA Technical Reports Server (NTRS)

Dorsey, John T.; Mikulas, Martin M.; Doggett, William R.

2008-01-01

The mass and sizing characteristics of manipulators for Lunar and Mars planetary surface applications are investigated by analyzing three structural configurations: a simple cantilevered boom with a square tubular cross-section; a hybrid cable/boom configuration with a square tubular cross-section support structure; and a hybrid cable/boom configuration with a square truss cross-section support structure. Design procedures are developed for the three configurations and numerical examples are given. A new set of performance parameters are developed that relate the mass of manipulators and cranes to a loading parameter. These parameters enable the masses of different manipulator configurations to be compared over a wide range of design loads and reach envelopes (radii). The use of these parameters is demonstrated in the form of a structural efficiency chart using the newly considered manipulator configurations. To understand the performance of Lunar and Mars manipulators, the design procedures were exercised on the three manipulator configurations assuming graphite/epoxy materials for the tubes and trusses. It is also assumed that the actuators are electric motor, gear reduction systems. Numerical results for manipulator masses and sizes are presented for a variety of manipulator reach and payload mass capabilities. Results are presented that demonstrate the sensitivity of manipulator mass to operational radius, tip force, and actuator efficiency. The effect of the value of gravitational force on the ratio of manipulator-mass to payload-mass is also shown. Finally, results are presented to demonstrate the relative mass reduction for the use of graphite/epoxy compared to aluminum for the support structure.

[The practice of special observation in adults in the German-speaking part of Switzerland - a descriptive cross-sectional study].

PubMed

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.

Development of a critical appraisal tool to assess the quality of cross-sectional studies (AXIS)

PubMed Central

Downes, Martin J; Brennan, Marnie L; Williams, Hywel C; Dean, Rachel S

2016-01-01

Objectives The aim of this study was to develop a critical appraisal (CA) tool that addressed study design and reporting quality as well as the risk of bias in cross-sectional studies (CSSs). In addition, the aim was to produce a help document to guide the non-expert user through the tool. Design An initial scoping review of the published literature and key epidemiological texts was undertaken prior to the formation of a Delphi panel to establish key components for a CA tool for CSSs. A consensus of 80% was required from the Delphi panel for any component to be included in the final tool. Results An initial list of 39 components was identified through examination of existing resources. An international Delphi panel of 18 medical and veterinary experts was established. After 3 rounds of the Delphi process, the Appraisal tool for Cross-Sectional Studies (AXIS tool) was developed by consensus and consisted of 20 components. A detailed explanatory document was also developed with the tool, giving expanded explanation of each question and providing simple interpretations and examples of the epidemiological concepts being examined in each question to aid non-expert users. Conclusions CA of the literature is a vital step in evidence synthesis and therefore evidence-based decision-making in a number of different disciplines. The AXIS tool is therefore unique and was developed in a way that it can be used across disciplines to aid the inclusion of CSSs in systematic reviews, guidelines and clinical decision-making. PMID:27932337

The Keynesian Diagram: A Cross to Bear?

ERIC Educational Resources Information Center

Fleck, Juergen

In elementary economics courses students are often introduced to the basic concepts of macroeconomics through very simplified static models, and the concept of a macroeconomic equilibrium is generally explained with the help of an aggregate demand/aggregate supply (AD/AS) model and an income/expenditure model (via the Keynesian cross diagram).…

Innovative Concepts and Technology for Railroad-Highway Grade Crossing Motorist Warning Systems : Volume 2. The Generation and Analysis of Alternative Concepts

DOT National Transportation Integrated Search

1977-09-01

The report describes the results of a study directed toward the generation, analysis and evaluation of innovative conceptual and technical approaches to train-activated motorist warning systems for use at railroad-highway grade crossings. Particular ...

Innovative Concepts and Technology for Railroad-Highway Grade Crossing Motorist Warning Systems : Volume 1. Overview and Concept Generation and Analysis

DOT National Transportation Integrated Search

1977-09-01

The document includes a general review of innovative conceptual and technical approaches to train-activated motorist warning systems for use at railroad-highway grade crossings, and also contains a specific report describing a study directed toward t...

Contemporary Studies on the Concept of Creativity: The East and the West.

ERIC Educational Resources Information Center

Niu, Weihua; Sternberg, Robert

2002-01-01

This article reviews contemporary studies on the concept of creativity across two cultures, Eastern cultures and Western cultures, by examining people's implicit theories of creativity across different cultures and cross-cultural studies of creativity. Cross-cultural studies revealed that Easterners and Westerners differ, on average, in their…

Predicting Phenotypes from Genetic Crosses: A Mathematical Concept to Help Struggling Biology Students

ERIC Educational Resources Information Center

Baurhoo, Neerusha; Darwish, Shireef

2012-01-01

Predicting phenotypic outcomes from genetic crosses is often very difficult for biology students, especially those with learning disabilities. With our mathematical concept, struggling students in inclusive biology classrooms are now better equipped to solve genetic problems and predict phenotypes, because of improved understanding of dominance…

Border Crossings and Multimodal Composition in the Arts

ERIC Educational Resources Information Center

Morrison, Andrew

2005-01-01

Developmental and development-oriented learning with digital media are discussed in relation to the concepts border crossings and multimodal composition. The first concept refers to a transveral of disciplines and recombinations of elements from them. Local-global relations in knowledge building are covered. The second refers to the collaborative…

The Self-Concept of the Elderly: A Cross-Cultural Comparison.

ERIC Educational Resources Information Center

Katzko, Michael W.; Steverink, Nardi; Dittmann-Kohli, Freya; Herrera, Ramona Rubio

1998-01-01

Examines the self-concept of the elderly from a cross-cultural perspective utilizing a sample of Spanish and Dutch elderly. Analysis focuses on responses to sentences which probed respondents' motivations and future plans and goals. Differences can be interpreted as reflecting an individualistic (Dutch) versus collectivistic (Spanish) distinction…

Self-concept and gender effects in Korean adolescents with epilepsy.

PubMed

Lee, Sang-Ahm; Choi, Eun-Ju; Kwon, Soonhak; Eom, Soyong

2016-08-01

We aimed to determine whether adolescents with epilepsy (AWE) have a compromised self-concept, whether a lower self-concept is related to mental health, and whether there are sex differences in self-concept in AWE. A total of 179 AWE and 259 control adolescents without epilepsy participated in this cross-sectional, multicenter study. Self-concept was measured using the Harter's Self-Perception Profile for Children. Depressive symptoms and anxiety were assessed by the Hospital Anxiety Depression Scale (HADS). A group-by-sex interaction was evaluated using an analysis of covariance controlling for age. Adolescents with epilepsy had a lower level of self-concept, especially in domains of behavioral conduct (partial eta(2): 0.257) and social acceptance (partial eta(2): 0.116), than controls (p<0.05). The level of self-concept did not differ by sex in the group with epilepsy. A group-by-sex interaction effect was found on social acceptance (p=0.042). Unlike the control group, age was not correlated with self-concept in AWE. Physical appearance was negatively correlated with HADS-anxiety scores (r=-0.291, p<0.01) but only in girls with epilepsy. Epilepsy duration was correlated with social acceptance in boys (r=0.211, p<0.05) and physical appearance in girls (r=-0.249, p<0.05). Adolescents with epilepsy had a lower level of self-concept, especially in the domains of behavioral conduct and social acceptance, than controls. Sex differences in self-concept were identified in the control group but not in the group with epilepsy. Physical appearance was negatively correlated with anxiety in girls with epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

Total cross sections for positrons scattered elastically from helium based on new measurements of total ionization cross sections

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

DOEpatents

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.

Geologic cross section C-C' through the Appalachian basin from Erie County, north-central Ohio, to the Valley and Ridge province, Bedford County, south-central Pennsylvania

USGS Publications Warehouse

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.

Multistrand superconductor cable

DOEpatents

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.

Verification and Validation for Flight-Critical Systems (VVFCS)

NASA Technical Reports Server (NTRS)

Graves, Sharon S.; Jacobsen, Robert A.

2010-01-01

On March 31, 2009 a Request for Information (RFI) was issued by NASA s Aviation Safety Program to gather input on the subject of Verification and Validation (V & V) of Flight-Critical Systems. The responses were provided to NASA on or before April 24, 2009. The RFI asked for comments in three topic areas: Modeling and Validation of New Concepts for Vehicles and Operations; Verification of Complex Integrated and Distributed Systems; and Software Safety Assurance. There were a total of 34 responses to the RFI, representing a cross-section of academic (26%), small & large industry (47%) and government agency (27%).

[Quality Manager 2.0 in hospitals: A practical guidance for executive managers, medical directors, senior consultants, nurse managers and practicing quality managers].

PubMed

Pilz, Stefan; Hülsmann, Sylvia; Michallik, Stefan; Rimbach-Schurig, Monika; Schollmeier, Margarita; Sommerhoff, Benedikt; Weßling, Adelheid

2013-01-01

Aiming at the development of perspectives and recommendations for modern quality management in health services the GQMG conducted a study on the role and self-conception of quality managers in hospitals. It seems obvious that the effectiveness of quality management clearly depends on the executive board's skilful installation of quality management, their support of quality managers and, particularly in larger-sized institutions on the coordination of staff units and cross-sectional functions.(As supplied by author). Copyright © 2013. Published by Elsevier GmbH.

A method of predicting the energy-absorption capability of composite subfloor beams

NASA Technical Reports Server (NTRS)

Farley, Gary L.

1987-01-01

A simple method of predicting the energy-absorption capability of composite subfloor beam structure was developed. The method is based upon the weighted sum of the energy-absorption capability of constituent elements of a subfloor beam. An empirical data base of energy absorption results from circular and square cross section tube specimens were used in the prediction capability. The procedure is applicable to a wide range of subfloor beam structure. The procedure was demonstrated on three subfloor beam concepts. Agreement between test and prediction was within seven percent for all three cases.

Flame deformation and entrainment associated with an isothermal transverse fuel jet

NASA Technical Reports Server (NTRS)

Jenkins, D. W.; Karagozian, A. R.

1992-01-01

This paper describes an analytical model of an incompressible, isothermal reacting jet in crossflow. The model represents the flow in the jet cross-section by a counter rotating vortex pair, a flow structure that has been observed to dominate the jet behavior. The reaction surface surrounding the fuel jet is represented as a composite of strained diffusion flames that are stretched and deformed by the vortex pair flow. The results shed new light on the interaction between the vortex pair circulation and flame structure evolution and their relation to the concept of entrainment.

A New Axi-Symmetric Element for Thin Walled Structures

NASA Astrophysics Data System (ADS)

Cardoso, Rui P. R.; Yoon, Jeong Whan; Dick, Robert E.

2010-06-01

A new axi-symmetric finite element for sheet metal forming applications is presented in this work. It uses the solid-shell element's concept with only a single element layer and multiple integration points along the thickness direction. The cross section of the element is composed of four nodes with two degrees of freedom each. The proposed formulation overcomes major locking pathologies including transverse shear locking, Poisson's locking and volumetric locking. Some examples are shown to demonstrate the performance and accuracy of the proposed element with special focus on the numerical simulations for the beverage can industry.

A mobile transporter concept for EVA assembly of future spacecraft

NASA Technical Reports Server (NTRS)

Watson, Judith J.; Bush, Harold G.; Heard, Walter L., Jr.; Lake, Mark S.; Jensen, J. Kermit

1990-01-01

This paper details the ground test program for the NASA Langley Research Center Mobile Transporter concept. The Mobile Transporter would assist EVA astronauts in the assembly of the Space Station Freedom. 1-g and simulated O-g (neutral buoyancy) tests were conducted to evaluate the use of the Mobile Transporter. A three-bay (44 struts) orthogonal tetrahedral truss configuration with a 15-foot-square cross section was repeatedly assembled by a single pair of pressure suited test subjects working from the Mobile Transporter astronaut positioning devices. The average unit assembly time was 28 seconds/strut. The results of these tests indicate that the use of a Mobile Transporter for EVA assembly of Space Station size structure is viable and practical. Additionally, the Mobile Transporter could be used to construct other spacecraft such as the submillimeter astronomical laboratory, space crane, and interplanetary (i.e., Mars and lunar) spacecraft.

Vortex generating flow passage design for increased film-cooling effectiveness and surface coverage. [aircraft engine blade cooling

NASA Technical Reports Server (NTRS)

Papell, S. S.

1984-01-01

The fluid mechanics of the basic discrete hole film cooling process is described as an inclined jet in crossflow and a cusp shaped coolant flow channel contour that increases the efficiency of the film cooling process is hypothesized. The design concept requires the channel to generate a counter rotating vortex pair secondary flow within the jet stream by virture of flow passage geometry. The interaction of the vortex structures generated by both geometry and crossflow was examined in terms of film cooling effectiveness and surface coverage. Comparative data obtained with this vortex generating coolant passage showed up to factors of four increases in both effectiveness and surface coverage over that obtained with a standard round cross section flow passage. A streakline flow visualization technique was used to support the concept of the counter rotating vortex pair generating capability of the flow passage design.

Orbit on demand - Will cost determine best design?

NASA Technical Reports Server (NTRS)

Macconochie, J. O.; Mackley, E. A.; Morris, S. J.; Phillips, W. P.; Breiner, C. A.; Scotti, S. J.

1985-01-01

Eleven design concepts for vertical (V) and horizontal (H) take-off launch-on-demand manned orbital vehicles are discussed. Attention is given to up to three stages, Mach numbers (sub-, 2, or 3), expendable boosters, drop tanks (DT), and storable (S) or cryogenic fuels. All the concepts feature lifting bodies with circular cross-section and most have a 7 ft diam, 15 ft long payload bay as well as a crew compartment. Expendable elements impose higher costs and in some cases reduce all-azimuth launch capabilities. Single-stage vehicles simplify the logistics whether in H or V configuration. A two-stage H vehicle offers launch offset for the desired orbital plane before firing the rocket engines after take-off and subsonic acceleration. A two-stage fully reusable V form has the second lowest weight of the vehicles studied and an all-azimuth launch capability. Better definition of the prospective mission requirements is needed before choosing among the alternatives.

Structural attachments for large space structures

NASA Technical Reports Server (NTRS)

Pruett, E. C.; Loughead, T. E.; Robertson, K. B., III

1980-01-01

The feasibility of fabricating beams in space and using them as components of a large, crew assembled structure, was investigated. Two projects were undertaken: (1) design and development of a ground version of an automated beam builder capable of producing triangular cross section aluminum beams; and (2) design and fabrication of lap joints to connect the beams orthogonally and centroidal end caps to connect beams end to end at any desired angle. The first project produced a beam building machine which fabricates aluminum beams suitable for neutral buoyancy evaluation. The second project produced concepts for the lap joint and end cap. However, neither of these joint concepts was suitable for use by a pressure suited crew member in a zero gravity environment. It is concluded that before the beams can be evaluated the joint designs need to be completed and sufficient joints produced to allow assembly of a complex structure.

Application of transmission loss concept in the evaluation of an acoustic filter for liquid-borne transverse resonance modes in a duct of circular cross section

NASA Technical Reports Server (NTRS)

Iwanicki, L. R.; Chang, Y. M.

1980-01-01

The transmission loss concept is used in the evaluation of an acoustic filter for liquid-borne transverse modes. Tests are conducted to determine the nature of filter element designs required to suppress transverse modes, to verify the presence of transverse modes in the test assembly, to define the acoustic wave incident, and to establish data recording, processing and analysis techniques providing transmission wave filter data. The first, second, and third tangential modes, and the first radial mode are found at frequencies of 2150, 3330, 4420, and 4110 Hz, respectively, and peaks of the tangential modes recede while the radial mode peak remains, demonstrating agreement with theoretical nodal patterns. The present design is found applicable to a liquid-oxygen system, and allows the easy-to-fabricate filter to fit within the available space envelope.

Vortex generating flow passage design for increased film-cooling effectiveness and surface coverage

NASA Astrophysics Data System (ADS)

Papell, S. S.

The fluid mechanics of the basic discrete hole film cooling process is described as an inclined jet in crossflow and a cusp shaped coolant flow channel contour that increases the efficiency of the film cooling process is hypothesized. The design concept requires the channel to generate a counter rotating vortex pair secondary flow within the jet stream by virture of flow passage geometry. The interaction of the vortex structures generated by both geometry and crossflow was examined in terms of film cooling effectiveness and surface coverage. Comparative data obtained with this vortex generating coolant passage showed up to factors of four increases in both effectiveness and surface coverage over that obtained with a standard round cross section flow passage. A streakline flow visualization technique was used to support the concept of the counter rotating vortex pair generating capability of the flow passage design.

Ultrasonic Imaging Modalities for Medical Applications

NASA Astrophysics Data System (ADS)

Ahmed, Mahfuz; Wade, Glen; Wang, Keith

1980-06-01

The ability to "see" with sound has long been an intriguing concept. Certain animals, such as bats and dolphins can do it readily but the human species is not so endowed by nature. However, this lack of natural ability has been overcome by developing an appropriate technology. For example, in various laboratories recently, workers were able to obtain true-focused orthographic images in real time of objects irradiated with sound rather than with light. Cross-sectional images have been available for a much longer period of time stemming from the development of pulse-echo techniques first used in the sonar systems of World War I. By now a wide variety of system concepts for acoustic imaging exist and have been or are being applied for medical diagnosis. The newer systems range from tomographic types using computers to holographic ones using lasers. These are dealt with briefly here.

Tactical missile aerodynamics

NASA Technical Reports Server (NTRS)

Hemsch, Michael J. (Editor); Nielsen, Jack N. (Editor)

1986-01-01

The present conference on tactical missile aerodynamics discusses autopilot-related aerodynamic design considerations, flow visualization methods' role in the study of high angle-of-attack aerodynamics, low aspect ratio wing behavior at high angle-of-attack, supersonic airbreathing propulsion system inlet design, missile bodies with noncircular cross section and bank-to-turn maneuvering capabilities, 'waverider' supersonic cruise missile concepts and design methods, asymmetric vortex sheding phenomena from bodies-of-revolution, and swept shock wave/boundary layer interaction phenomena. Also discussed are the assessment of aerodynamic drag in tactical missiles, the analysis of supersonic missile aerodynamic heating, the 'equivalent angle-of-attack' concept for engineering analysis, the vortex cloud model for body vortex shedding and tracking, paneling methods with vorticity effects and corrections for nonlinear compressibility, the application of supersonic full potential method to missile bodies, Euler space marching methods for missiles, three-dimensional missile boundary layers, and an analysis of exhaust plumes and their interaction with missile airframes.

Subfertility in relation to welding. A case referent study among male welders.

PubMed

Bonde, J P

1990-02-01

A recent report indicates that welding work is associated with increased risk of reduced semen quality. The purpose of this study was to investigate a possible association between welding exposure and male subfertility. A cross-sectional population of 673 metal workers and electricians employed at six major Danish work places in the same geographic area constituted the study population. Data on reproductive and occupational experience was obtained by means of a self-administered postal questionnaire. The response rate was 79 percent among welders and 83 percent among the other workers. A significantly increased rate of delayed conception in relation to welding work at the time of this event was observed when self-reported welding exposure among cases of delayed conception was compared to welding exposure both among age-matched referents and among referents with a child born without delay in conception. However, in the first approach the risk dropped to insignificant levels when adjustments were made for potential confounding factors. This preliminary study has methodological drawbacks, and the association between welding exposure and male fertility should be investigated further.

Sexual Orientation Self-Concept Ambiguity: Scale Adaptation and Validation.

PubMed

Talley, Amelia E; Stevens, Jordan E

2017-07-01

The current article describes the adaptation of a measure of sexual orientation self-concept ambiguity (SSA) from an existing measure of general self-concept clarity. Latent "trait" scores of SSA reflect the extent to which a person's beliefs about their own sexual orientation are perceived as inconsistent, unreliable, or incongruent. Sexual minority and heterosexual women ( n = 348), ages 18 to 30, completed a cross-sectional survey. Categorical confirmatory factor analysis guided the selection of items to form a 10-item, self-report measure of SSA. In the current report, we also examine (a) reliability of the 10-item scale score, (b) measurement invariance based on respondents' sexual identity status and age group, and (c) correlations with preexisting surveys that purport to measure similar constructs and theoretical correlates. Evidence for internal reliability, measurement invariance (based on respondent sex), and convergent validity was also investigated in an independent, validation sample. The lowest SSA scores were reported by women who self-ascribed an exclusively heterosexual or exclusively lesbian/gay sexual identity, whereas those who reported a bisexual, mostly lesbian/gay, or mostly heterosexual identity, reported relatively higher SSA scores.

Study for requirement of advanced long life small modular fast reactor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tak, Taewoo, E-mail: ttwispy@unist.ac.kr; Choe, Jiwon, E-mail: chi91023@unist.ac.kr; Jeong, Yongjin, E-mail: yjjeong09@unist.ac.kr

2016-01-22

To develop an advanced long-life SMR core concept, the feasibility of the long-life breed-and-burn core concept has been assessed and the preliminary selection on the reactor design requirement such as fuel form, coolant material has been performed. With the simplified cigar-type geometry of 8m-tall CANDLE reactor concept, it has demonstrated the strengths of breed-and-burn strategy. There is a saturation region in the graph for the multiplication factors, which means that a steady breeding is being proceeded along the axial direction. The propagation behavior of the CANDLE core can be also confirmed through the evolution of the axial power profile. Coolantmore » material is expected to have low melting point, density, viscosity and absorption cross section and a high boiling point, specific heat, and thermal conductivity. In this respect, sodium is preferable material for a coolant of this nuclear power plant system. The metallic fuel has harder spectrum compared to the oxide and carbide fuel, which is favorable to increase the breeding and extend the cycle length.« less

Study for requirement of advanced long life small modular fast reactor

NASA Astrophysics Data System (ADS)

Tak, Taewoo; Choe, Jiwon; Jeong, Yongjin; Lee, Deokjung; Kim, T. K.

2016-01-01

To develop an advanced long-life SMR core concept, the feasibility of the long-life breed-and-burn core concept has been assessed and the preliminary selection on the reactor design requirement such as fuel form, coolant material has been performed. With the simplified cigar-type geometry of 8m-tall CANDLE reactor concept, it has demonstrated the strengths of breed-and-burn strategy. There is a saturation region in the graph for the multiplication factors, which means that a steady breeding is being proceeded along the axial direction. The propagation behavior of the CANDLE core can be also confirmed through the evolution of the axial power profile. Coolant material is expected to have low melting point, density, viscosity and absorption cross section and a high boiling point, specific heat, and thermal conductivity. In this respect, sodium is preferable material for a coolant of this nuclear power plant system. The metallic fuel has harder spectrum compared to the oxide and carbide fuel, which is favorable to increase the breeding and extend the cycle length.

The self-concept of the elderly: a cross-cultural comparison.

PubMed

Katzko, M W; Steverink, N; Dittmann-Kohli, F; Herrera, R R

1998-01-01

This study examines the self-concept of the elderly in a cross-cultural perspective. An open-ended sentence completion methodology was employed. A sample of elderly Spanish and elderly Dutch were compared to gain an idea of the cross-cultural generality of the content of the self-concept. Analysis focuses on responses to sentences which probed the respondents' motivations and future plans and goals. Differences could be interpreted as reflecting an individualistic (Dutch) vs. collectivistic (Spanish) distinction between the two cultures. Furthermore, the findings had implications for how to interpret dimensions of meaningful aging. For example, a dimension such as "purpose in life" was more generalizable across the two samples than a dimension such as "autonomy."

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

Cross-Disciplinary Thermoregulation and Sweat Analysis Laboratory Experiences for Undergraduate Chemistry and Exercise Science Students

ERIC Educational Resources Information Center

Mulligan, Gregory; Taylor, Nichole; Glen, Mary; Tomlin, Dona; Gaul, Catherine A.

2011-01-01

Cross-disciplinary (CD) learning experiences benefit student understanding of concepts and curriculum by offering opportunities to explore topics from the perspectives of alternate fields of study. This report involves a qualitative evaluation of CD health sciences undergraduate laboratory experiences in which concepts and students from two…

Trunk Muscle Size and Composition Assessment in Older Adults with Chronic Low Back Pain: An Intra-Examiner and Inter-Examiner Reliability Study.

PubMed

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.

Calculation of total and ionization cross sections for electron scattering by primary benzene compounds

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.

Developing high-performance cross-functional teams: Understanding motivations, functional loyalties, and teaming fundamentals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, M.A.

1996-08-01

Teamwork is the key to the future of effective technology management. Today`s technologies and markets have become too complex for individuals to work alone. Global competition, limited resources, cost consciousness, and time pressures have forced organizations and project managers to encourage teamwork. Many of these teams will be cross-functional teams that can draw on a multitude of talents and knowledge. To develop high-performing cross-functional teams, managers must understand motivations, functional loyalties, and the different backgrounds of the individual team members. To develop a better understanding of these issues, managers can learn from experience and from literature on teams and teamingmore » concepts. When studying the literature to learn about cross-functional teaming, managers will find many good theoretical concepts, but when put into practice, these concepts have varying effects. This issue of varying effectiveness is what drives the research for this paper. The teaming concepts were studied to confirm or modify current understanding. The literature was compared with a {open_quotes}ground truth{close_quotes}, a survey of the reality of teaming practices, to examine the teaming concepts that the literature finds to be critical to the success of teams. These results are compared to existing teams to determine if such techniques apply in real-world cases.« less

An investigation of MCNP6.1 beryllium oxide S(α, β) cross sections

DOE PAGES

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.

Ethnic differences in attitudes and bias toward older people comparing White and Asian nursing students.

PubMed

Lee, Young-Shin

2015-03-01

To identify attitudes and bias toward aging between Asian and White students and identify factors affecting attitudes toward aging. A cross-sectional sample of 308 students in a nursing program completed the measure of Attitudes Toward Older People and Aging Quiz electronically. There were no differences in positive attitudes and pro-aged bias between Asian and White groups, but Asian students had significantly more negative attitudes and anti-aged bias toward older people than White students. Multiple regression analysis showed ethnicity/race was the strongest variable to explain negative attitudes toward older people. Feeling uneasy about talking to older adults was the most significant factor to explain all attitudinal concepts. Asian students were uneasy about talking with older people and had negative attitudes toward older adults. To become competent in cross-cultural care and communication in nursing, educational strategies to reduce negative attitudes on aging are necessary. © The Author(s) 2014.

GUST LAT Multiwavelength Planning

NASA Technical Reports Server (NTRS)

Thompson, D. J.

2004-01-01

Because gamma-ray astrophysics profits in powerful ways from multi-wavelength studies, the GLAST Large Area Telescope (LAT) Collaboration has started multiwavelength planning well before the scheduled 2007 launch. Many aspects of this program are of direct interest to observers using VERITAS and other atmospheric Cerenkov telescopes, whose capabilities complement those of GLAST. This talk with describe some of the current developmental concepts for GLAST LAT multiwavelength work, including release of data for transient sources, nearly-continuous monitoring of selected time-variable sources, pulsar timing, follow-on observations for source identification, coordinated blazar campaigns, and cross-calibration with other high-energy telescopes. Although few details are firm at this stage of preparation for GLAST, the LAT Collaboration looks forward to cooperation with a broad cross-section of the multiwave-length community. The GLAST Large Area Telescope is an international effort, with U.S. funding provided by the Department of Energy and NASA.

Do Spanish Medical Students Understand the Concept of Brain Death?

PubMed

Ríos, Antonio; López-Navas, A; López-López, A; Gómez, F J; Iriarte, J; Herruzo, R; Blanco, G; Llorca, F J; Asunsolo, A; Sánchez, P; Gutiérrez, P R; Fernández, A; de Jesús, M T; Alarcón, L Martínez; Del Olivo, M; Fuentes, L; Hernández, J R; Virseda, J; Yelamos, J; Bondía, J A; Hernández, A M; Ayala, M A; Ramírez, P; Parrilla, P

2018-03-01

To analyze the level of understanding of the brain death concept among medical students in universities in Spain. This cross-sectional sociological, interdisciplinary, and multicenter study was performed on 9598 medical students in Spain. The sample was stratified by geographical area and academic year. A previously validated self-reported measure of brain death knowledge (questionnaire Proyecto Colaborativo Internacional Donante sobre la Donación y Transplante de Organos) was completed anonymously by students. Respondents completed 9275 surveys for a completion rate of 95.7%. Of those, 67% (n = 6190) of the respondents understood the brain death concept. Of the rest, 28% (n = 2652) did not know what it meant, and the remaining 5% (n = 433) believed that it did not mean that the patient was dead. The variables related to a correct understanding of the concept were: (1) being older ( P < .001), (2) studying at a public university ( P < .001), (3) year of medical school ( P < .001), (4) studying at one of the universities in the south of Spain ( P = .003), (5) having discussed donation and transplantation with the family ( P < .001), (6) having spoken to friends about the matter ( P < .001), (7) a partner's favorable attitude toward donation and transplantation ( P < .001), and (8) religious beliefs ( P < .001). Sixty-seven percent of medical students know the concept of brain death, and knowledge improved as they advanced in their degree.

Improved structure and long-life blanket concepts for heliotron reactors

NASA Astrophysics Data System (ADS)

Sagara, A.; Imagawa, S.; Mitarai, O.; Dolan, T.; Tanaka, T.; Kubota, Y.; Yamazaki, K.; Watanabe, K. Y.; Mizuguchi, N.; Muroga, T.; Noda, N.; Kaneko, O.; Yamada, H.; Ohyabu, N.; Uda, T.; Komori, A.; Sudo, S.; Motojima, O.

2005-04-01

New design approaches are proposed for the LHD-type heliotron D-T demo-reactor FFHR2 to solve the key engineering issues of blanket space limitation and replacement difficulty. A major radius of over 14 m is selected to permit a blanket-shield thickness of about 1 m and to reduce the neutron wall loading and toroidal field, while achieving an acceptable cost of electricity. Two sets of optimization are successfully carried out. One is to reduce the magnetic hoop force on the helical coil support structures by adjustment of the helical winding coil pitch parameter and the poloidal coils design, which facilitates expansion of the maintenance ports. The other is a long-life blanket concept using carbon armour tiles that soften the neutron energy spectrum incident on the self-cooled flibe-reduced activation ferritic steel blanket. In this adaptation of the spectral-shifter and tritium breeder blanket (STB) concept a local tritium breeding ratio over 1.2 is feasible by optimized arrangement of the neutron multiplier Be in the carbon tiles, and the radiation shielding of the superconducting magnet coils is also significantly improved. Using constant cross sections of a helically winding shape, the 'screw coaster' concept is proposed to replace in-vessel components such as the STB armour tiles. The key R&D issues for developing the STB concept, such as radiation effects on carbon and enhanced heat transfer of Flibe, are elucidated.

Peer Attachment, Perceived Parenting Style, Self-concept, and School Adjustments in Adolescents with Chronic Illness.

PubMed

Ahn, Jeong-Ah; Lee, Sunhee

2016-12-01

The purpose of this study was to identify how peer attachment and parenting style differentially affect self-concept and school adjustment in adolescents with and without chronic illness. A cross-sectional study using multiple group analysis on the Korean panel data was used. A nationwide stratified multistage cluster sampling method was used and the survey was conducted in 2013 on 2,092 first-year middle school students in Korea. We used standardized instruments by the National Youth Policy Institute to measure peer attachment, parenting style, self-concept, and school adjustment. Multiple-group structural equation modeling was used to evaluate the difference of relations for peer attachment, parenting style, self-concept, and school adjustment variable between adolescents with chronic illness and those without chronic illness. The model fit of a multiple-group structural equation modeling was good. The difference of the path from negative parenting style to self-concept between the two groups was significant, and a significant between-group difference in the overall path was found. This indicated that self-concept in adolescents with chronic illness was more negatively affected by negative parenting style than in adolescents without chronic illness. Healthcare providers can promote the process of school adjustment in several ways, such as discussing this issue directly with adolescent patients, along with their parents and peers, examining how the organization and content of the treatment can be modified according to the adolescents' school life. Copyright © 2016. Published by Elsevier B.V.

Geologic Cross Section E-E' through the Appalachian Basin from the Findlay Arch, Wood County, Ohio, to the Valley and Ridge Province, Pendleton County, West Virginia

USGS Publications Warehouse

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).

The Mini-CAPTAIN Neutron Run and Future CAPTAIN Program

NASA Astrophysics Data System (ADS)

Cooper, Robert; CAPTAIN Collaboration

2016-09-01

The Cryogenic Apparatus for Precision Tests of Argon Interaction with Neutrinos (CAPTAIN) is an experimental program to measure critical neutrino interaction cross sections in argon for the DUNE long-baseline program. These cross sections are important for understanding and improving the energy resolution of measurements for neutrino oscillations and supernova detection in argon. The full CAPTAIN detector is a 5-ton fiducial volume liquid argon (LAr) time-projection chamber (TPC) with an independently triggered photon detection system (PDS) for fast-timing capabilities on accelerators. To test the full CAPTAIN concept, the 1-ton fiducial volume mini-CAPTAIN detector has been deployed. Mini-CAPTAIN is another LAr TPC with PDS. It was recently deployed to the Weapons Neutron Research (WNR) facility at Los Alamos National Laboratory to measure high-energy neutron interactions in argon. The WNR is a pulsed accelerator capable of delivering neutrons up to 800 MeV in energy. In this talk, I will report on the analysis of the first time-of-flight tagged, high-energy neutron response in liquid argon from our February 2016 run. I will also highlight a second neutron run at the WNR scheduled for Summer 2017 and discuss the implications these data have on the future CAPTAIN program.

Resilience to suicidal ideation in psychosis: Positive self-appraisals buffer the impact of hopelessness.

PubMed

Johnson, J; Gooding, P A; Wood, A M; Taylor, P J; Pratt, D; Tarrier, N

2010-09-01

Recent years have seen growing interest into concepts of resilience, but minimal research has explored resilience to suicide and none has investigated resilience to suicide amongst clinical groups. The current study aimed to examine whether a proposed resilience factor, positive self-appraisals of the ability to cope with emotions, difficult situations and the ability to gain social support, could buffer against the negative impact of hopelessness amongst individuals with psychosis-spectrum disorders when measured cross-sectionally. Seventy-seven participants with schizophrenia-spectrum disorders completed self-report measures of suicidal ideation, hopelessness and positive self-appraisals. Positive self-appraisals were found to moderate the association between hopelessness and suicidal ideation. For those reporting high levels of positive self-appraisals, increased levels of hopelessness were significantly less likely to lead to suicidality. These results provide cross-sectional evidence suggest that positive self-appraisals may buffer individuals with psychosis against the pernicious impact of a well known clinical risk factor, hopelessness. Accounting for positive self-appraisals may improve identification of individuals at high risk of suicidality, and may be an important area to target for suicide interventions. 2010 Elsevier Ltd. All rights reserved.

Evidence based medicine: teaching, learning and practice: results of a cross-sectional study from Turkey.

PubMed

Avsar, Ummu Zeynep; Avsar, Umit; Cansever, Zeliha; Acemoglu, Hamit; Cayir, Yasemin; Khan, Abdul Sattar

2014-07-01

To assess the level of understanding related to the significance of evidence-based medicine among physicians. The cross-sectional study was conducted between March and October 2012 using an online questionnaire that was sent out to physicians and academics working as faculty at training hospitals across Turkey. The questionnaire consisted of questions about the knowledge, attitude and behaviour towards evidence-based medicine. Seven of the questions pertained to the learning of evidence-based medicine, six were about teaching evidence-based medicine, and six were about its practice. SPSS 20 was used for statistical analyses. The questionnaire was returned duly filled by 79 physicians. Of them, 41 (51.9%) were males; and 57 (72.2%) were part of the faculty. Only 1(1.2%) participant had attended a course about evidence-based medicine during undergraduate education, while 19 (24.05)had attended one after graduation. Besides, 26 (32.9%) academics were teaching some concepts of evidence-based medicine, and 21 (26.6%) were giving some information about clinical guidelines. The study found that levels of learning and teaching of evidence-based medicine among physicians were inadequate. They should be emphasised at both pre- and post-graduate tiers.

Temperature-dependent spectroscopy and microchip laser operation of Nd:KGd(WO4)2

NASA Astrophysics Data System (ADS)

Loiko, P.; Yoon, S. J.; Serres, J. M.; Mateos, X.; Beecher, S. J.; Birch, R. B.; Savitski, V. G.; Kemp, A. J.; Yumashev, K.; Griebner, U.; Petrov, V.; Aguiló, M.; Díaz, F.; Mackenzie, J. I.

2016-08-01

High-resolution absorption and stimulated-emission cross-section spectra are presented for monoclinic Nd:KGd(WO4)2 (Nd:KGW) laser crystals in the temperature range 77-450 K. At room-temperature, the maximum stimulated emission cross-section is σSE = 21.4 × 10-20 cm2 at 1067.3 nm, for light polarization E || Nm. The lifetime of the 4F3/2 state of Nd3+ in KGW is practically temperature independent at 115 ± 5 μs. Measurement of the energy transfer upconversion parameter for a 3 at.% Nd:KGW crystal proved that this was significantly smaller than for alternative hosts, ∼2.5 × 10-17 cm3/s. When cut along the Ng optical indicatrix axis, the Nd:KGW crystal was configured as a microchip laser, generating ∼4 W of continuous-wave output at 1067 nm with a slope efficiency of 61% under diode-pumping. Using a highly-doped (10 at.%) Nd:KGW crystal, the slope efficiency reached 71% and 74% when pumped with a laser diode and a Ti:Sapphire laser, respectively. The concept of an ultrathin (250 μm) Nd:KGW microchip laser sandwiched between two synthetic diamond heat-spreaders is demonstrated.

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

DOEpatents

Sheffield, George V.

1977-01-01

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

A Bag of Concepts Approach for Biomedical Document Classification Using Wikipedia Knowledge*. Spanish-English Cross-language Case Study.

PubMed

Mouriño-García, Marcos A; Pérez-Rodríguez, Roberto; Anido-Rifón, Luis E

2017-10-26

The ability to efficiently review the existing literature is essential for the rapid progress of research. This paper describes a classifier of text documents, represented as vectors in spaces of Wikipedia concepts, and analyses its suitability for classification of Spanish biomedical documents when only English documents are available for training. We propose the cross-language concept matching (CLCM) technique, which relies on Wikipedia interlanguage links to convert concept vectors from the Spanish to the English space. The performance of the classifier is compared to several baselines: a classifier based on machine translation, a classifier that represents documents after performing Explicit Semantic Analysis (ESA), and a classifier that uses a domain-specific semantic annotator (MetaMap). The corpus used for the experiments (Cross-Language UVigoMED) was purpose-built for this study, and it is composed of 12,832 English and 2,184 Spanish MEDLINE abstracts. The performance of our approach is superior to any other state-of-the art classifier in the benchmark, with performance increases up to: 124% over classical machine translation, 332% over MetaMap, and 60 times over the classifier based on ESA. The results have statistical significance, showing p-values < 0.0001. Using knowledge mined from Wikipedia to represent documents as vectors in a space of Wikipedia concepts and translating vectors between language-specific concept spaces, a cross-language classifier can be built, and it performs better than several state-of-the-art classifiers.

BACKSCAT Lidar Simulation Version 3.0: Technical Documentation and Users Guide

DTIC Science & Technology

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

Use of apparent thickness for preprocessing of low-frequency electromagnetic data in inversion-based multibarrier evaluation workflow

NASA Astrophysics Data System (ADS)

Omar, Saad; Omeragic, Dzevat

2018-04-01

The concept of apparent thicknesses is introduced for the inversion-based, multicasing evaluation interpretation workflow using multifrequency and multispacing electromagnetic measurements. A thickness value is assigned to each measurement, enabling the development of two new preprocessing algorithms to remove casing collar artifacts. First, long-spacing apparent thicknesses are used to remove, from the pipe sections, artifacts ("ghosts") caused by the transmitter crossing a casing collar or corrosion. Second, a collar identification, localization, and assignment algorithm is developed to enable robust inversion in collar sections. Last, casing eccentering can also be identified on the basis of opposite deviation of short-spacing phase and magnitude apparent thicknesses from the nominal value. The proposed workflow can handle an arbitrary number of nested casings and has been validated on synthetic and field data.

Academic Self-Concept and Achievement in Polish Primary Schools: Cross-Lagged Modelling and Gender-Specific Effects

ERIC Educational Resources Information Center

Grygiel, Pawel; Modzelewski, Michal; Pisarek, Jolanta

2017-01-01

This study reports relationships between general academic self-concept and achievement in grade 3 and grade 5. Gender-specific effects were investigated using a longitudinal, two-cycle, 3-year autoregressive cross-lagged panel design in a large, representative sample of Polish primary school pupils (N = 4,226). Analysis revealed (a) reciprocal…

Cross-Grade Comparison of Students' Understanding of Energy Concepts

ERIC Educational Resources Information Center

Saglam-Arslan, Aysegul

2010-01-01

The aims of this cross-grade study were (1) to determine the level of understanding of energy concepts of students at different academic grades and the differences in understanding between these grades and (2) to analyse the conceptual development of these students. Two hundred and forty-three students at 3 different levels (high school,…

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

DOE PAGES

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

SU-E-U-02: The Development of a Practical Ultrasonic System for Cross-Sectional Imaging of Small Animals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kamp, J; Karmanos Cancer Institute - International Imaging Center, Detroit, MI; Malyarenko, E

Purpose: To test the feasibility of developing a practical medium frequency ultrasound tomography method for small animal imaging. The ability to produce cross-sectional or full body images of a live small animal using a low-cost tabletop ultrasound scanner without any special license would be very beneficial to long term biological studies, where repeated scanning is often required over an extended period of time. Methods: The cross sectional images were produced by compounding multiple B-scans of a laboratory phantom or an animal acquired at different projection angles. Two imaging systems were used to test the concept. The first system included amore » programmable 64-channel phased array controller driving a 128-channel, 5–10 MHz linear probe to produce 143 B-Mode projections of the spinning object. The second system designed and manufactured in house, produced 64 or 128 B-Mode projections with a single unfocused 8 MHz transducer scanning with a 0.116 mm step size. Results: The phased array system provided good penetration through the phantoms/mice (with the exception of the lungs) and allowed to acquire data in a very short time. The cross-sectional images have enough resolution and dynamic range to detect both high- and low-contrast organs. The single transducer system takes longer to scan, and the data require more sophisticated processing. To date, our images allow seeing details as small as 1–2 mm in the phantoms and in small animals, with the contrast mostly due to highly reflecting bones and air inclusions. Conclusion: The work indicates that very detailed and anatomically correct images can be created by relatively simple and inexpensive means. With more advanced algorithms and improved system design, scan time can be reduced considerably, enabling high-resolution full 3D imaging. This will allow for quick and easy scans that can help monitor tumor growth and/or regression without contributing any dose to the animal. The authors would like to acknowledge the financial and engineering support from Tessonics.« less

Design, manufacturing and measurement of a PV miniconcentrator for front point-contact silicon solar cells

NASA Astrophysics Data System (ADS)

Pérez, D.; Miñano, J. C.; Benítez, P.; Muñoz, F.; Mohedano, R.

2005-08-01

A novel photovoltaic concentrator has been developed in the framework of the European project "High efficiency silicon solar cells concentrator". In this project, front-contacted silicon solar cell have also been designed and manufactured by the project leader (the French LETI). This silicon cell concept is potentially capable to perform well (24% efficiency has been predicted) for much higher concentration levels than the back-contacted cells (and, of course, than the two-side contacted cells). The concentrator is formed by one lens of squared contour with flat entry surface and large-facet Fresnel exit surface, and a secondary that encapsulates the solar cell. On the contrary to the conventional Fresnel lens plus nonimaging secondary concentrators, the primary and secondary are designed simultaneously, leading to better concentration-acceptance angle product without compromise with the compactness. The grid lines in the front-contacted cells are aluminium prisms (which contact the p+ and n+ emitters, alternatively), acting as a linear cone concentrator that concentrates Cg =1.52× in the cross sectional dimension of the prisms. The secondary concentrator has a refractive rotational symmetric top surface that is crossed with two linear flow-line TIR mirror. Then, in the cross section normal to the aluminium prisms, the secondary provides a 2D concentration of Cg =12×, while in the cross section parallel to the prisms it provides a 2D concentration of Cg =24.16× as the grid lines in this dimension. Therefore, the cell is rectangular (1:2.08 aspect ratio), being the grid lines parallel to the shorter rectangle side. The total 3D geometrical concentration is 24.16×(12×1.52) = 455× for the square aperture and rectangular cell, and gets a design acceptance angle α=+/-1.8 degrees. Injection moulded prototypes are have been manufactured and measured, proving an optical efficiency of 79%. Computer modelling of the concentrator performance will also be presented.

Self-concept clarity and religious orientations: prediction of purpose in life and self-esteem.

PubMed

Błażek, Magdalena; Besta, Tomasz

2012-09-01

The present study concerns the relationship between self-concept clarity, religiosity, and well-being, as well as the mediating influence of religiosity on the relationship between self-concept clarity and sense of meaning in life and self-esteem. Self-concept clarity was found to be a significant predictor of sense of meaning in life and self-esteem; intrinsic religious orientation was found to be a predictor of sense of meaning in life, while the quest religious orientation was a predictor for self-esteem. The cross-products of self-concept clarity and intrinsic religious orientation were found to be related to the sense of purpose in life, which would point to religiosity being a mediator of the relationship between self-concept clarity and sense of purpose in life. The cross-products of self-concept clarity and quest religious orientation were found to be a predictor of self-esteem, which indicates a mediating effect of this religious orientation in the relationship of self-concept clarity and self-esteem.

The association between global self-esteem, physical self-concept and actual vs ideal body size rating in Chinese primary school children.

PubMed

Lau, P W C; Lee, A; Ransdell, L; Yu, C W; Sung, R Y T

2004-02-01

To investigate whether the discrepancy between actual and ideal body size rating is related to Chinese children's global self-esteem and global physical self-concept. A cross-sectional study of school children who completed questionnaires related to global self-esteem, global physical self-concept, and actual vs ideal body size. A total of 386 Chinese children (44% girls and 56% boys) aged 7-13 y from a primary school in Hong Kong, China. Global self-esteem and physical self-concept were measured using the physical self-descriptive questionnaire. Actual vs ideal body size discrepancy was established using the silhouette matching task. No significant relationship was found between global self-esteem and actual-ideal body size discrepancy of children. Global physical self-concept had a moderate negative correlation (r=-0.12) with the body size discrepancy score and the discrepancy score explained very limited variance (R(2)=0.015; F(1, 296)=4.51; P<0.05) in global physical self-concept. Three body size discrepancy groups (none, positive, and negative) were examined to see if there were any significant differences in global self-esteem, global physical self-concept, and specific dimensions of physical self-concept. A significant overall difference was found between groups for global physical self-concept (F=3.73, P<0.05) and the physical self-concept subscales of physical activity (F=3.25, P<0.05), body fat (F=61.26, P<0.001), and strength (F=5.26, P<0.01). Boys scored significantly higher than girls on global physical self-concept-especially in the sport competence, strength, and endurance subscales. This study revealed that the actual-ideal body size discrepancy rating of Chinese children was not predictive of global physical self-concept and global self-esteem. These findings are contrary to those reported in Western children, which may mean that culture plays a role in the formation of body attitude.

Similarity and accuracy of mental models formed during nursing handovers: A concept mapping approach.

PubMed

Drach-Zahavy, Anat; Broyer, Chaya; Dagan, Efrat

2017-09-01

Shared mental models are crucial for constructing mutual understanding of the patient's condition during a clinical handover. Yet, scant research, if any, has empirically explored mental models of the parties involved in a clinical handover. This study aimed to examine the similarities among mental models of incoming and outgoing nurses, and to test their accuracy by comparing them with mental models of expert nurses. A cross-sectional study, exploring nurses' mental models via the concept mapping technique. 40 clinical handovers. Data were collected via concept mapping of the incoming, outgoing, and expert nurses' mental models (total of 120 concept maps). Similarity and accuracy for concepts and associations indexes were calculated to compare the different maps. About one fifth of the concepts emerged in both outgoing and incoming nurses' concept maps (concept similarity=23%±10.6). Concept accuracy indexes were 35%±18.8 for incoming and 62%±19.6 for outgoing nurses' maps. Although incoming nurses absorbed fewer number of concepts and associations (23% and 12%, respectively), they partially closed the gap (35% and 22%, respectively) relative to expert nurses' maps. The correlations between concept similarities, and incoming as well as outgoing nurses' concept accuracy, were significant (r=0.43, p<0.01; r=0.68 p<0.01, respectively). Finally, in 90% of the maps, outgoing nurses added information concerning the processes enacted during the shift, beyond the expert nurses' gold standard. Two seemingly contradicting processes in the handover were identified. "Information loss", captured by the low similarity indexes among the mental models of incoming and outgoing nurses; and "information restoration", based on accuracy measures indexes among the mental models of the incoming nurses. Based on mental model theory, we propose possible explanations for these processes and derive implications for how to improve a clinical handover. Copyright © 2017 Elsevier Ltd. All rights reserved.

Knowledge, attitudes, and practices regarding conception and fertility: a population-based survey among reproductive-age United States women.

PubMed

Lundsberg, Lisbet S; Pal, Lubna; Gariepy, Aileen M; Xu, Xiao; Chu, Micheline C; Illuzzi, Jessica L

2014-03-01

To assess overall knowledge, attitudes, and practices related to conception and fertility among reproductive-age women in the United States. Online survey of a cross-sectional sample of 1,000 women. United States, March 2013. Women aged 18-40 years. None. Knowledge, attitudes, and practices regarding selected topics in reproductive health. Forty percent of women across all age groups expressed concerns about their ability to conceive. Yet one-third of women were unaware of adverse implications of sexually transmitted infections, obesity, or irregular menses for procreative success, and one-fifth were unaware of the effects of aging. Approximately 40% were unfamiliar with the ovulatory cycle. Overall, younger women (18-24 years) demonstrated less knowledge regarding conception, fertility, and ovulation, whereas older women tended to believe in common myths and misconceptions. Respondents in all age groups identified women's health care providers (75%) and Web sites (40%) as top sources of reproductive health-related information; however, engagement with providers on specific factors affecting fertility is sparse. Knowledge regarding ovulation, fertility, and conception is limited among this sample of reproductive-age US women. Future initiatives should prioritize improved provider engagement and accurate information dissemination in Web-based venues. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Exploring the Assessment of the DSM-5 Alternative Model for Personality Disorders With the Personality Assessment Inventory.

PubMed

Busch, Alexander J; Morey, Leslie C; Hopwood, Christopher J

2017-01-01

Section III of the Diagnostic and Statistical Manual of Mental Disorders (5th ed. [DSM-5]; American Psychiatric Association, 2013) contains an alternative model for the diagnosis of personality disorder involving the assessment of 25 traits and a global level of overall personality functioning. There is hope that this model will be increasingly used in clinical and research settings, and the ability to apply established instruments to assess these concepts could facilitate this process. This study sought to develop scoring algorithms for these alternative model concepts using scales from the Personality Assessment Inventory (PAI). A multiple regression strategy used to predict scores in 2 undergraduate samples on DSM-5 alternative model instruments: the Personality Inventory for the DSM-5 (PID-5) and the General Personality Pathology scale (GPP; Morey et al., 2011 ). These regression functions resulted in scores that demonstrated promising convergent and discriminant validity across the alternative model concepts, as well as a factor structure in a cross-validation sample that was congruent with the putative structure of the alternative model traits. Results were linked to the PAI community normative data to provide normative information regarding these alternative model concepts that can be used to identify elevated traits and personality functioning level scores.

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.

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.

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.

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

Cross section and γ-ray spectra for U238(n,γ) measured with the DANCE detector array at the Los Alamos Neutron Science Center

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.

High resolution absorption cross sections in the transmission window region of the Schumann-Runge bands and Herzberg continuum of O2

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.

CEPXS

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.

Inelastic cross sections for low-energy electrons in liquid water: exchange and correlation effects.

PubMed

Emfietzoglou, Dimitris; Kyriakou, Ioanna; Garcia-Molina, Rafael; Abril, Isabel; Nikjoo, Hooshang

2013-11-01

Low-energy electrons play a prominent role in radiation therapy and biology as they are the largest contributor to the absorbed dose. However, no tractable theory exists to describe the interaction of low-energy electrons with condensed media. This article presents a new approach to include exchange and correlation (XC) effects in inelastic electron scattering at low energies (below ∼10 keV) in the context of the dielectric theory. Specifically, an optical-data model of the dielectric response function of liquid water is developed that goes beyond the random phase approximation (RPA) by accounting for XC effects using the concept of the many-body local-field correction (LFC). It is shown that the experimental energy-loss-function of liquid water can be reproduced by including into the RPA dispersion relations XC effects (up to second order) calculated in the time-dependent local-density approximation with the addition of phonon-induced broadening in N. D. Mermin's relaxation-time approximation. Additional XC effects related to the incident and/or struck electrons are included by means of the vertex correction calculated by a modified Hubbard formula for the exchange-only LFC. Within the first Born approximation, the present XC corrections cause a significantly larger reduction (∼10-50%) to the inelastic cross section compared to the commonly used Mott and Ochkur approximations, while also yielding much better agreement with the recent experimental data for amorphous ice. The current work offers a manageable, yet rigorous, approach for including non-Born effects in the calculation of inelastic cross sections for low-energy electrons in liquid water, which due to its generality, can be easily extended to other condensed media.

Investigating Elementary Teachers' Conceptions of Animal Classification

ERIC Educational Resources Information Center

Burgoon, Jacob N.; Duran, Emilio

2012-01-01

Numerous studies have been conducted regarding alternative conceptions about animal diversity and classification, many of which have used a cross-age approach to investigate how students' conceptions change over time. None of these studies, however, have investigated teachers' conceptions of animal classification. This study was intended to…

Rapid mix concepts for low emission combustors in gas turbine engines

NASA Technical Reports Server (NTRS)

Talpallikar, Milind V.; Smith, Clifford E.; Lai, Ming-Chia

1990-01-01

NASA LeRC has identified the Rich burn/Quick mix/Lean burn (RQL) combustor as a potential gas turbine combustor concept to reduce NOx emissions in High Speed Civil Transport (HSCT) aircraft. To demonstrate reduced NOx levels, NASA LeRC soon will test a flametube version of an RQL combustor. The critical technology needed for the RQL combustor is a method of quickly mixing combustion air with rich burn gases. Two concepts were proposed to enhance jet mixing in a circular cross-section: the Asymmetric Jet Penetration (AJP) concept; and the Lobed Mixer (LM) concept. In Phase 1, two preliminary configurations of the AJP concept were compared with a conventional 12-jet radial-inflow slot design. The configurations were screened using an advanced 3-D Computational Fluid Dynamics (CFD) code named REFLEQS. Both non-reacting and reacting analyses were performed. For an objective comparison, the conventional design was optimized by parametric variation of the jet-to-mainstream momentum flux (J) ratio. The optimum J was then employed in the AJP simulations. Results showed that the three-jet AJP configuration was superior in overall mixedness compared to the conventional design. However, in regards to NOx emissions, the AJP configuration was inferior. The higher emission level for AJP was caused by a single hot spot located in the wake of the central jet as it entered the combustor. Ways of maintaining good mixedness while eliminating the hot spot were identified for Phase 2 study. Overall, Phase 1 showed the viability of using CFD analyses to evaluate quick-mix concepts. A high probability exists that advancing mixing concepts will reduce NOx emissions in RQL combustors, and should be explored in Phase 2, by parallel numerical and experimental work.

Geologic Cross Section D-D' Through the Appalachian Basin from the Findlay Arch, Sandusky County, Ohio, to the Valley and Ridge Province, Hardy County, West Virginia

USGS Publications Warehouse

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.

COHeRE: Cross-Ontology Hierarchical Relation Examination for Ontology Quality Assurance.

PubMed

Cui, Licong

Biomedical ontologies play a vital role in healthcare information management, data integration, and decision support. Ontology quality assurance (OQA) is an indispensable part of the ontology engineering cycle. Most existing OQA methods are based on the knowledge provided within the targeted ontology. This paper proposes a novel cross-ontology analysis method, Cross-Ontology Hierarchical Relation Examination (COHeRE), to detect inconsistencies and possible errors in hierarchical relations across multiple ontologies. COHeRE leverages the Unified Medical Language System (UMLS) knowledge source and the MapReduce cloud computing technique for systematic, large-scale ontology quality assurance work. COHeRE consists of three main steps with the UMLS concepts and relations as the input. First, the relations claimed in source vocabularies are filtered and aggregated for each pair of concepts. Second, inconsistent relations are detected if a concept pair is related by different types of relations in different source vocabularies. Finally, the uncovered inconsistent relations are voted according to their number of occurrences across different source vocabularies. The voting result together with the inconsistent relations serve as the output of COHeRE for possible ontological change. The highest votes provide initial suggestion on how such inconsistencies might be fixed. In UMLS, 138,987 concept pairs were found to have inconsistent relationships across multiple source vocabularies. 40 inconsistent concept pairs involving hierarchical relationships were randomly selected and manually reviewed by a human expert. 95.8% of the inconsistent relations involved in these concept pairs indeed exist in their source vocabularies rather than being introduced by mistake in the UMLS integration process. 73.7% of the concept pairs with suggested relationship were agreed by the human expert. The effectiveness of COHeRE indicates that UMLS provides a promising environment to enhance qualities of biomedical ontologies by performing cross-ontology examination.

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.

Student-Centered Reliability, Concurrent Validity and Instructional Sensitivity in Scoring of Students' Concept Maps in a University Science Laboratory

ERIC Educational Resources Information Center

Kaya, Osman Nafiz; Kilic, Ziya

2004-01-01

Student-centered approach of scoring the concept maps consisted of three elements namely symbol system, individual portfolio and scoring scheme. We scored student-constructed concept maps based on 5 concept map criteria: validity of concepts, adequacy of propositions, significance of cross-links, relevancy of examples, and interconnectedness. With…

Politics of Leadership and Implementation of Educational Policies and Programmes of Tertiary Institutions in Cross River State, Nigeria

ERIC Educational Resources Information Center

Ekpiken, W. E.; Ifere, Francis O.

2015-01-01

This paper examines issues of politics of leadership and implementation of Educational policies and programmes of tertiary institutions in Cross River State with a view to determine the problems are situated and suggest the way forward. It examines the concept of politics of education, concept of leadership, meaning of planning and generation of…

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.

Calculation of total electron excitation cross-sections and partial electron ionization cross-sections for the elements. Ph.D. Thesis

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.

Rayleigh scattering cross sections of combustion species at 266, 355, and 532 nm for thermometry applications.

PubMed

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.

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

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.

Why live recording sounds better: a case study of Schumann's Träumerei

PubMed Central

Shoda, Haruka; Adachi, Mayumi

2015-01-01

We explore the concept that artists perform best in front of an audience. The negative effects of performance anxiety are much better known than their related cousin on the other shoulder: the positive effects of “social facilitation.” The present study, however, reveals a listener's preference for performances recorded in front of an audience. In Study 1, we prepared two types of recordings of Träumerei performed by 13 pianists: recordings in front of an audience and those with no audience. According to the evaluation by 153 listeners, the recordings performed in front of an audience sounded better, suggesting that the presence of an audience enhanced or facilitated the performance. In Study 2, we analyzed pianists' durational and dynamic expressions. According to the functional principal components analyses, we found that the expression of “Träumerei” consisted of three components: the overall quantity, the cross-sectional contrast between the final and the remaining sections, and the control of the expressive variability. Pianists' expressions were targeted more to the “average” of the cross-sectional variation in the audience-present than in the audience-absent recordings. In Study 3, we explored a model that explained listeners' responses induced by pianists' acoustical expressions, using path analyses. The final model indicated that the cross-sectional variation of the duration and that of the dynamics determined listeners' evaluations of the quality and the emotionally moving experience, respectively. In line with human's preferences for commonality, the more “average” the durational expressions were in live recording, the better the listeners' evaluations were regardless of their musical experiences. Only the well-experienced listeners (at least 16 years of musical training) were moved more by the “deviated” dynamic expressions in live recording, suggesting a link between the experienced listener's emotional experience and the unique dynamics in music. PMID:25620948

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.

Using thermochonology to validate a balanced cross section along the Karnali River, far-western Nepal

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.

Scattered light and accuracy of the cross-section measurements of weak absorptions: Gas and liquid phase UV absorption cross sections of CH3CFCl2

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.

Annual variations of water vapor in the stratosphere and upper troposphere observed by the Stratospheric Aerosol and Gas Experiment II

NASA Technical Reports Server (NTRS)

Mccormick, M. P.; Chiou, E. W.; Mcmaster, L. R.; Chu, W. P.; Larsen, J. C.; Rind, D.; Oltmans, S.

1993-01-01

Data collected by the Stratospheric Aerosol and Gas Experiment II are presented, showing annual variations of water vapor in the stratosphere and the upper troposphere. The altitude-time cross sections of water vapor were found to exhibit annually repeatable patterns in both hemispheres, with a yearly minimum in water vapor appearing in both hemispheres at about the same time, supporting the concept of a common source for stratospheric dry air. A linear regression analysis was applied to the three-year data set to elucidate global values and variations of water vapor ratio.

Design and implementation of distributed multimedia surveillance system based on object-oriented middleware

NASA Astrophysics Data System (ADS)

Cao, Xuesong; Jiang, Ling; Hu, Ruimin

2006-10-01

Currently, the applications of surveillance system have been increasingly widespread. But there are few surveillance platforms that can meet the requirement of large-scale, cross-regional, and flexible surveillance business. In the paper, we present a distributed surveillance system platform to improve safety and security of the society. The system is constructed by an object-oriented middleware called as Internet Communications Engine (ICE). This middleware helps our platform to integrate a lot of surveillance resource of the society and accommodate diverse range of surveillance industry requirements. In the follow sections, we will describe in detail the design concepts of system and introduce traits of ICE.

Nanostructured organosilicon luminophores as a new concept of nanomaterials for highly efficient down-conversion of light

NASA Astrophysics Data System (ADS)

Ponomarenko, Sergey A.; Surin, Nikolay M.; Borshchev, Oleg V.; Skorotetcky, Maxim S.; Muzafarov, Aziz M.

2015-10-01

Nanostructured organosilicon luminophores (NOLs) are branched molecular structures having two types of covalently bonded via silicon atoms organic luminophores with efficient Förster energy transfer between them. They combine the best properties of organic luminophores and inorganic quantum dots: high absorption cross-section, excellent photoluminescence quantum yield, fast luminescence decay time, good processability and low toxicity. A smart choice of organic luminophores allowed us to design and synthesize a library of NOLs, absorbing from VUV to visible region and emitting at the desired wavelengths from 390 to 650 nm. They can be used as unique wavelength shifters in plastic scintillators and other applications.

Resonant inelastic scattering by use of geometrical optics.

PubMed

Schulte, Jörg; Schweiger, Gustav

2003-02-01

We investigate the inelastic scattering on spherical particles that contain one concentric inclusion in the case of input and output resonances, using a geometrical optics method. The excitation of resonances is included in geometrical optics by use of the concept of tunneled rays. To get a quantitative description of optical tunneling on spherical surfaces, we derive appropriate Fresnel-type reflection and transmission coefficients for the tunneled rays. We calculate the inelastic scattering cross section in the case of input and output resonances and investigate the influence of the distribution of the active material in the particle as well as the influence of the inclusion on inelastic scattering.

A multicore optical fiber for distributed sensing

NASA Astrophysics Data System (ADS)

Sun, Xiaoguang; Li, Jie; Burgess, David T.; Hines, Mike; Zhu, Beyuan

2014-06-01

With advancements in optical fiber technology, the incorporation of multiple sensing functionalities within a single fiber structure opens the possibility to deploy dielectric, fully distributed, long-length optical sensors in an extremely small cross section. To illustrate the concept, we designed and manufactured a multicore optical fiber with three graded-index (GI) multimode (MM) cores and one single mode (SM) core. The fiber was coated with both a silicone primary layer and an ETFE buffer for high temperature applications. The fiber properties such as geometry, crosstalk and attenuation are described. A method for coupling the signal from the individual cores into separate optical fibers is also presented.

Morphology-Dependent Resonances of Spherical Droplets with Numerous Microscopic Inclusions

NASA Technical Reports Server (NTRS)

Mishchenko, Michael I.; Liu, Li; Mackowski, Daniel W.

2014-01-01

We use the recently extended superposition T-matrix method to study the behavior of a sharp Lorenz-Mie resonance upon filling a spherical micrometer-sized droplet with tens and hundreds of randomly positioned microscopic inclusions. We show that as the number of inclusions increases, the extinction cross-section peak and the sharp asymmetry-parameter minimum become suppressed, widen, and move toward smaller droplet size parameters, while ratios of diagonal elements of the scattering matrix exhibit sharp angular features indicative of a distinctly nonspherical particle. Our results highlight the limitedness of the concept of an effective refractive index of an inhomogeneous spherical particle.

Methods And Apparatus For Acoustic Fiber Fractionation

DOEpatents

Brodeur, Pierre

1999-11-09

Methods and apparatus for acoustic fiber fractionation using a plane ultrasonic wave field interacting with water suspended fibers circulating in a channel flow using acoustic radiation forces to separate fibers into two or more fractions based on fiber radius, with applications of the separation concept in the pulp and paper industry. The continuous process relies on the use of a wall-mounted, rectangular cross-section piezoelectric ceramic transducer to selectively deflect flowing fibers as they penetrate the ultrasonic field. The described embodiment uses a transducer frequency of approximately 150 kHz. Depending upon the amount of dissolved gas in water, separation is obtained using a standing or a traveling wave field.

Bulky Counterions: Enhancing the Two-Photon Excited Fluorescence of Gold Nanoclusters.

PubMed

Bertorelle, Franck; Moulin, Christophe; Soleilhac, Antonin; Comby-Zerbino, Clothilde; Dugourd, Philippe; Russier-Antoine, Isabelle; Brevet, Pierre-François; Antoine, Rodolphe

2018-01-19

Increasing fluorescence quantum yields of ligand-protected gold nanoclusters has attracted wide research interest. The strategy consisting in using bulky counterions has been found to dramatically enhance the fluorescence. In this Communication, we push forward this concept to the nonlinear optical regime. We show that by an appropriate choice of bulky counterions and of solvent, a 30-fold increase in two-photon excited fluorescence (TPEF) signal at ≈600 nm for gold nanoclusters can be obtained. This would correspond to a TPEF cross-section in the range of 0.1 to 1 GM. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

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.

Kinematic Modeling of Central Nepal: Thermochronometer Cooling Ages as a Constraint for Balanced Cross Sections

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.

Optimization of Orifice Geometry for Cross-Flow Mixing in a Cylindrical Duct

NASA Technical Reports Server (NTRS)

Kroll, J. T.; Sowa, W. A.; Samuelsen, G. S.

1996-01-01

Mixing of gaseous jets in a cross-flow has significant applications in engineering, one example of which is the dilution zone of a gas turbine combustor. Despite years of study, the design of the jet injection in combustors is largely based on practical experience. The emergence of NO(x) regulations for stationary gas turbines and the anticipation of aero-engine regulations requires an improved understanding of jet mixing as new combustor concepts are introduced. For example, the success of the staged combustor to reduce the emission of NO(x) is almost entirely dependent upon the rapid and complete dilution of the rich zone products within the mixing section. It is these mixing challenges to which the present study is directed. A series of experiments was undertaken to delineate the optimal mixer orifice geometry. A cross-flow to core-flow momentum-flux ratio of 40 and a mass flow ratio of 2.5 were selected as representative of a conventional design. An experimental test matrix was designed around three variables: the number of orifices, the orifice length-to- width ratio, and the orifice angle. A regression analysis was performed on the data to arrive at an interpolating equation that predicted the mixing performance of orifice geometry combinations within the range of the test matrix parameters. Results indicate that the best mixing orifice geometry tested involves eight orifices with a long-to-short side aspect ratio of 3.5 at a twenty-three degree inclination from the center-line of the mixing section.

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.

Measurements of absolute absorption cross sections of ozone in the 185- to 254-nm wavelength region and the temperature dependence

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

DOE PAGES

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.

Solid oxide fuel cell with transitioned cross-section for improved anode gas management at the open end

DOEpatents

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

DOEpatents

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.

Technological and cross-border mixture value chain of science and engineering of multi-integrative mechatronics-integronics-adaptronics

NASA Astrophysics Data System (ADS)

Gheorghe, Gh. Ion; Popan, Gheorghe

2013-10-01

This scientific paper presents in national premiere and in original concept of the author, the scientific national and the author's original concept, the technological and cross-border mixture value chain of science and engineering of multi-integrative Mechatronics-Integronics-Adaptronics, as high-tech vector support development, for viability and sustainability of a new intelligent and competitive labour market.

Robert A. Roessel Jr. and Navajo Community College: Cross-Cultural Roles of Key Individuals in its Creation, 1951-1989

ERIC Educational Resources Information Center

Barrett, T. Gregory; Thaxton, Lourene

2007-01-01

This article's thesis is that a cross-cultural brokerage composed of Indians and non-Indians was essential for bringing the Navajo Community College (NCC) to fruition. To explain this brokerage, the study first examines the concept of cultural brokerage and then uses the concept as a lens through which to explore the roles of various…

Cross-Age Tutoring: A Strategy for Increasing Reading Achievement and Improving Self-Concept for Elementary School Children.

ERIC Educational Resources Information Center

Wood, Edwin Leon

This study attempted to determine the effects of a twice-weekly, four-month-long, cross-age tutoring program on children's reading achievement levels and self-concepts. A total of 240 students, stratified by grade and sex, were randomly assigned to four experimental groups. Within each group, students were matched by grade: grade four with grade…

A mobile work station concept for mechanically aided astronaut assembly of large space trusses

NASA Technical Reports Server (NTRS)

Heard, W. L., Jr.; Bush, H. G.; Wallson, R. E.; Jensen, J. K.

1983-01-01

This report presents results of a series of truss assembly tests conducted to evaluate a mobile work station concept intended to mechanically assist astronaut manual assembly of erectable space trusses. The tests involved assembly of a tetrahedral truss beam by a pair of test subjects with and without pressure (space) suits, both in Earth gravity and in simulated zero gravity (neutral buoyancy in water). The beam was assembled from 38 identical graphite-epoxy nestable struts, 5.4 m in length with aluminum quick-attachment structural joints. Struts and joints were designed to closely simulate flight hardware. The assembled beam was approximately 16.5 m long and 4.5 m on each of the four sides of its diamond-shaped cross section. The results show that average in-space assembly rates of approximately 38 seconds per strut can be expected for struts of comparable size. This result is virtually independent of the overall size of the structure being assembled. The mobile work station concept would improve astronaut efficiency for on-orbit manual assembly of truss structures, and also this assembly-line method is highly competitive with other construction methods being considered for large space structures.

Resilience research in schizophrenia: a review of recent developments.

PubMed

Mizuno, Yuya; Wartelsteiner, Fabienne; Frajo-Apor, Beatrice

2016-05-01

The concept of resilience is expected to be relevant in understanding the heterogeneous outcomes associated with schizophrenia. We reviewed recent developments in clinical studies focusing on the biological and psychological aspects of resilience in this population. We aimed to clarify current concepts of resilience in the field, elucidate gaps in the literature, and provide recommendations for future research. A total of 20 articles published between 2014 and 2015 were included. Six studies were neuroimaging studies, while the remaining studies used various psychological assessments. Most studies were cross-sectional except for three studies with naturalistic follow-up, one single-blind randomized controlled trial, and two published protocols of prospective studies. The following patterns of research were evident among the highly heterogeneous literature: studies focusing on protective factors and others emphasizing dynamic processes, studies investigating 'at-risk but resilient' groups (e.g. nonpsychotic siblings of patients with schizophrenia), and studies using psychological scales to measure resilience. The heterogeneity in how reports conceptualize, assess, and interpret resilience likely reflects the multidimensional nature of the concept itself and the lack of a 'gold standard' in assessing resilience in schizophrenia. Further research is needed to make recommendations on how to facilitate resilience in clinical care.

Fragmentation cross sections of medium-energy {sup 35}Cl, {sup 40}Ar, and {sup 48}Ti beams 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 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

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.

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.

The role of disability self-concept in adaptation to congenital or acquired disability.

PubMed

Bogart, Kathleen R

2014-02-01

Current theories of adaptation to disability do not address differences in adaptation to congenital or acquired disability. Although people with congenital disabilities are generally assumed to be better adapted than people with acquired disabilities, few studies have tested this, and even fewer have attempted to explain the mechanisms behind these differences. This study tested the proposition that whether a disability is congenital or acquired plays an important role in the development of the disability self-concept (consisting of disability identity and disability self-efficacy), which in turn, affects satisfaction with life. It was predicted that disability self-concept would be better developed among people with congenital, compared with acquired disabilities, predicting greater satisfaction with life in those with acquired conditions. 226 participants with congenital and acquired mobility disabilities completed a cross-sectional online questionnaire measuring satisfaction with life, self-esteem, disability identity, disability self-efficacy, and demographic information. Self-esteem, disability identity, disability self-efficacy, and income were significant predictors of satisfaction with life. Congenital onset predicted higher satisfaction with life; disability identity and disability self-efficacy, but not self-esteem, partially mediated the relationship. Findings highlight the distinction between adaptation to congenital versus acquired disability and the importance of disability self-concept, which are underresearched constructs. Results suggest that rather than attempting to "normalize" individuals with disabilities, health care professionals should foster their disability self-concept. Possible ways to improve disability self-concept are discussed, such as involvement in the disability community and disability pride. PsycINFO Database Record (c) 2014 APA, all rights reserved.

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.

Semi-empirical scaling for ion-atom single charge exchange cross sections in the intermediate velocity regime

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.

PubMed

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.

Semi-empirical and empirical L X-ray production cross sections for elements with 50 ⩽ Z ⩽ 92 for protons of 0.5 3.0 MeV

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

DOE PAGES

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.

Neutron Thermal Cross Sections, Westcott Factors, Resonance Integrals, Maxwellian Averaged Cross Sections and Astrophysical Reaction Rates Calculated from the ENDF/B-VII.1, JEFF-3.1.2, JENDL-4.0, ROSFOND-2010, CENDL-3.1 and EAF-2010 Evaluated Data Libraries

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.

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.

Single step sequential polydimethylsiloxane wet etching to fabricate a microfluidic channel with various cross-sectional geometries

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.

The formation of excited atoms during charge exchange between hydrogen ions and alkali atoms. Ph.D. Thesis

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.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schulz, H.

In the updating of the Guidelines for PWR`s of the {open_quotes}Reaktor-Sicherheitskommission{close_quotes} (RSK) in 1981 the requirements on the design have been changed with respect to the postulated leaks and breaks in the primary pressure boundary. The major change was a revision in the requirements for pipe whip protection. As a logical consequence of the {open_quotes}concept of basic safety{close_quotes} a guillotine type break or any other break type resulting in a large opening is not postulated any longer for the calculation of reaction and jet forces. As an upper limit for a leak an area of 0, 1 A (A =more » open cross section of the pipe) is postulated. This decision was based on a general assessment of the present PWR system design in Germany. Since then a number of piping systems have been requalified in the older nuclear power plants to comply with the break preclusion concept. Also a number of extensions of the concept have been developed to cover also leak-assumptions for branch pipes. Furthermore due considerations have been given to other aspects which could contribute to a leak development in the primary circuit, like vessel penetrations, manhole covers, flanges, etc. Now the break preclusion concept originally applied to the main piping has been developed into an integrated concept for the whole pressure boundary within the containment and will be applied also in the periodic safety review of present nuclear power plants.« less

Living with Genetic Risk: Effect on Adolescent Self-Concept

PubMed Central

McConkie-Rosell, Allyn; Spiridigliozzi, Gail A.; Melvin, Elizabeth; Dawson, Deborah V.; Lachiewicz, Ave M.

2009-01-01

The purpose of this study is to describe the interplay of adolescent girls’ self-concept, coping behaviors, and adjustment associated with knowledge of genetic risk for fragile X syndrome. We will report here findings on self concept. Using a multi-group cross-sectional design this study focused on girls ages 14–25 years from families previously diagnosed with fragile X syndrome, who knew they were 1) carriers (n = 20; mean age 18.35 years s.d. 2.5), or 2) noncarriers (n =18; mean age 17.78 years s.d. 2.69), or 3) at-risk to be carriers (n = 15; mean age 17.87 s.d. 3.18). The girls completed the Tennessee Self Concept Scale (TSCS:2), a visual analog scale, and a guided interview. Total and all subscale scores on the TSCS:2 were in the normal range for all three groups. However, threats to self concept were found in personal self (physical self, genetic identity, and parental role), social self, and family self (family genetic identity) as they specifically related to the meaning of genetic information and varied based on risk status. Our findings suggest that risk information itself is threatening and for some girls, may be as threatening as learning one is a carrier. Certainty related to genetic risk status appears to make a positive difference for some girls by allowing them the opportunity to face the challenge of their genetic risk status and to begin to consider the meaning of this information. PMID:18200514

Drug Use among Residents of Juvenile Correctional Center in Kerman, Iran, and its Relationship with Personality Dimensions and Self-concept

PubMed Central

Gousheh, Amin; Ziaaddini, Hassan; Baneshi, Mohammad Reza; Nakhaee, Nouzar

2014-01-01

Background Identifying the status of substance misuse and its psychosocial correlates among residents of juvenile correctional centers, as a high risk group, could potentially illuminate the roadmap to prevention of drug use in this group. Methods In this cross-sectional study, 93 individuals aged 13 to 18 were enrolled. A self-administered questionnaire was completed and dropped in a sealed box. It consisted of 4 parts of Piers-Harris Children’s Self-Concept Scale, NEO Personality Inventory, drug use questions, and demographic variables. All questionnaires were well adapted in the Persian language. MANOVA was used to compare the subscale scores between the drug users and nonusers. Findings All respondents were male and 40% were illiterate. More than 40% had drug dependent fathers. Use of cigarette, opium, and alcohol in the previous 30 days was reported by 31.9, 52.2, and 15.9% of respondents, respectively. In this population, the score of 3 of the 5 personality factors (i.e., neuroticism, extraversion, and openness) were higher than in the general population (P < 0.001). More than 88% of subjects had negative self-concept. Both the scores of personality and self-concept showed no significant difference based on the status of drug use. Conclusion Prevalence of lifetime and last-month drug use was found to be high. Regarding the profiles of personality and self-concept, more comprehensive evidence-based interventions are needed for improvement of their mental health. PMID:25140214

Neutron Fission of 235,237,239U and 241,243Pu: Cross Sections, Integral Cross Sections and Cross Sections on Excited States

DOE Office of Scientific and Technical Information (OSTI.GOV)

Younes, W; Britt, H C

In a recent paper submitted to Phys. Rev. C they have presented estimates for (n,f) cross sections on a series of Thorium, Uranium and Plutonium isotopes over the range E{sub n} = 0.1-2.5 MeV. The (n,f) cross sections for many of these isotopes are difficult or impossible to measure in the laboratory. The cross sections were obtained from previous (t,pf) reaction data invoking a model which takes into account the differences between (t,pf) and (n,f) reaction processes, and which includes improved estimates for the neutron compound formation process. The purpose of this note is: (1) to compare the estimated crossmore » sections to current data files in both ENDF and ENDL databases; (2) to estimate ratios of cross sections relatively to {sup 235}U integrated over the ''tamped flattop'' critical assembly spectrum that was used in the earlier {sup 237}U report; and (3) to show the effect on the integral cross sections when the neutron capturing state is an excited rotational state or an isomer. The isomer and excited state results are shown for {sup 235}U and {sup 237}U.« less

How do Students Conceptualise Health and its Risk Factors? A Study among Iranian Schoolchildren

PubMed Central

Haghdoost, Ali-Akbar; Ashrafi Asgar-Abad, Ahad; Shokoohi, Mostafa; Alam, Mahin; Esmaeili, Maryam; Hojabri, Neda

2013-01-01

Background: To assess the concept of children concerning their health and its risk factors, a group of primary and middle school students were asked to draw a few relevant pictures in order to deeply explore the comprehension of this key group. Methods: In this cross-sectional study 1165 students, aged 7-15 years old, selected through random stratified sampling, were asked to draw a number of eight paintings, four paintings on health concepts, and the other four on health risk factors. The paintings were then assessed by two independent observers, and their themes and contents were abstracted and analysed. Results: The students drew a total of 2330 paintings, 1165 paintings on the concept of health, and 1165 paintings on health risk factors. The most and least expressed health concepts concerned “mental health” and “healthy diet” (73.3% and 4.8%, respectively). Considering health risk factors, “unhealthy diet” and the two concepts of “environmental hazards” and “neglected personal hygiene” had the most (95%) and least (1.4% each) frequencies. Students in public schools, primary level and girls drew more pictures about health concept or/and its risk factors (P<0.05). The association between parents’ education level and the numbers of pictures were not statistically significant. Conclusion: Although students had a broad view about health and its risk factors, generally little attention had been paid to some of the main aspects such as physical activity, healthy diet, mental and oral health, and environmental hazards. In addition, it seems that parents’ educational level, as one of the main socio-economic factors, did not have any significant impact on their concepts. PMID:24596834

Effect of reagent rotation on the integral cross-sections and isotopic branching of the reactions H - + HD and D - + HD

NASA Astrophysics Data System (ADS)

Zhang, Wei; Liu, Yufang; He, Xiaohu

2010-04-01

A quasi-classical trajectory (QCT) method has been used to calculate integral reaction cross-section for H - + HD and D - + HD. The influence of rotation of the reagent on the integral reaction cross-section and the product branching ratios of the title reactions are discussed. The results indicate that the reactive cross-section of H(D) - + HD → HH(D) + D - decreases with an increase of the j for E tran ⩽ 1.5 eV. The results also show that the reactive cross-section of D(H) - + HD → DD(H) + H - decreases with an increase of the j for E tran ⩽ 1.0 eV and that the integral cross-sections of title reactions are sensitive to the reagent rotation.

Evaluation of cross sections for neutron-induced reactions in sodium. [10/sup -5/ eV to 20 MeV

DOE Office of Scientific and Technical Information (OSTI.GOV)

Larson, D.C.

1980-09-01

An evaluation of the neutron-induced cross sections of /sup 23/Na has been done for the energy range from 10/sup -5/ eV to 20 MeV. All significant cross sections are given, including differential cross sections for production of gamma rays. The recommended values are based on experimental data where available, and use results of a consistent model code analysis of available data to predict cross sections where there are no experimental data. This report describes the evaluation that was submitted to the Cross Section Evaluation Working Group (CSEWG) for consideration as a part of the Evaluated Nuclear Data File, Version V,more » and subsequently issued as MAT 1311. 126 references, 130 figures, 14 tables.« less

Three-dimensional object surface identification

NASA Astrophysics Data System (ADS)

Celenk, Mehmet

1995-03-01

This paper describes a computationally efficient matching method for inspecting 3D objects using their serial cross sections. Object regions of interest in cross-sectional binary images of successive slices are aligned with those of the models. Cross-sectional differences between the object and the models are measured in the direction of the gradient of the cross section boundary. This is repeated in all the cross-sectional images. The model with minimum average cross-sectional difference is selected as the best match to the given object (i.e., no defect). The method is tested using various computer generated surfaces and matching results are presented. It is also demonstrated using Symult S-2010 16-node system that the method is suitable for parallel implementation in massage passing processors with the maximum attainable speedup (close to 16 for S-2010).

Polynomial coefficients for calculating O2 Schumann-Runge cross sections at 0.5/cm resolution

NASA Technical Reports Server (NTRS)

Minschwaner, K.; Anderson, G. P.; Hall, L. A.; Yoshino, K.

1992-01-01

O2 cross sections from 49,000 to 57,000/cm have been fitted with temperature dependent polynomial expressions, providing an accurate and efficient means of determining Schumann-Runge band cross sections for temperatures between 130 and 500 K. The least squares fits were carried out on a 0.5/cm spectral grid, using cross sections obtained from a Schumann-Runge line-by-line model that incorporates the most recent spectroscopic data. The O2 cross sections do not include the underlying Herzberg continuum, but they do contain contributions from the temperature dependent Schumann-Runge continuum. The cross sections are suitable for use in UV transmission calculations at high spectral resolution. They should also prove useful for updating existing parameterizations of ultraviolet transmission and O2 photolysis.

An Equivalent cross-section Framework for improving computational efficiency in Distributed Hydrologic Modelling

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.

Assessment of experimental d-PIGE γ-ray production cross sections for 12C, 14N and 16O and comparison with absolute thick target yields

NASA Astrophysics Data System (ADS)

Csedreki, L.; Halász, Z.; Kiss, Á. Z.

2016-08-01

Measured differential cross sections for deuteron induced γ-ray emission from the reactions 12C(d,pγ)13C, (Eγ = 3089 keV), 14N(d,pγ)15N (Eγ = 8310 keV) and 16O(d,pγ)17O (Eγ = 871 keV) available in the literature were assessed. In order to cross check the assessed γ-ray production cross section data, thick target γ-yields calculated from the differential cross sections were compared with available measured thick target yields. Recommended differential cross section data for each reaction were deduced for particle induced γ-ray emission (PIGE) applications.

Electron-impact excitation cross sections for the b /sup 3/. sigma. /sub u//sup +/ state of H/sub 2/

DOE Office of Scientific and Technical Information (OSTI.GOV)

Khakoo, M.A.; Trajmar, S.; McAdams, R.

1987-04-01

Differential and integral cross sections for electron-impact excitation of the b /sup 3/..sigma../sub u//sup +/ state of H/sub 2/ have been determined in the 20--100-eV impact energy region. The calibration of the cross sections was achieved through the H/sub 2/ elastic scattering cross sections, which in turn were normalized to absolute He elastic scattering cross sections. Comparison is made with available experimental data and with theoretical results applying Born-Ochkur-Rudge, distorted-wave, and close-coupling approximations.

New Tools to Prepare ACE Cross-section Files for MCNP Analytic Test Problems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Forrest B.

Monte Carlo calculations using one-group cross sections, multigroup cross sections, or simple continuous energy cross sections are often used to: (1) verify production codes against known analytical solutions, (2) verify new methods and algorithms that do not involve detailed collision physics, (3) compare Monte Carlo calculation methods with deterministic methods, and (4) teach fundamentals to students. In this work we describe 2 new tools for preparing the ACE cross-section files to be used by MCNP ® for these analytic test problems, simple_ace.pl and simple_ace_mg.pl.

Measurement of Charged and Neutral Current e-p Deep Inelastic Scattering Cross Sections at High Q2

NASA Astrophysics Data System (ADS)

Derrick, M.; Krakauer, D.; Magill, S.; Mikunas, D.; Musgrave, B.; Repond, J.; Stanek, R.; Talaga, R. L.; Zhang, H.; Ayad, R.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Bruni, P.; Cara Romeo, G.; Castellini, G.; Chiarini, M.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; Gialas, I.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Margotti, A.; Massam, T.; Nania, R.; Nemoz, C.; Palmonari, F.; Polini, A.; Sartorelli, G.; Timellini, R.; Zamora Garcia, Y.; Zichichi, A.; Bargende, A.; Crittenden, J.; Desch, K.; Diekmann, B.; Doeker, T.; Eckert, M.; Feld, L.; Frey, A.; Geerts, M.; Geitz, G.; Grothe, M.; Haas, T.; Hartmann, H.; Haun, D.; Heinloth, K.; Hilger, E.; Jakob, H.-P.; Katz, U. F.; Mari, S. M.; Mass, A.; Mengel, S.; Mollen, J.; Paul, E.; Rembser, Ch.; Schattevoy, R.; Schramm, D.; Stamm, J.; Wedemeyer, R.; Campbell-Robson, S.; Cassidy, A.; Dyce, N.; Foster, B.; George, S.; Gilmore, R.; Heath, G. P.; Heath, H. F.; Llewellyn, T. J.; Morgado, C. J.; Norman, D. J.; O'Mara, J. A.; Tapper, R. J.; Wilson, S. S.; Yoshida, R.; Rau, R. R.; Arneodo, M.; Iannotti, L.; Schioppa, M.; Susinno, G.; Bernstein, A.; Caldwell, A.; Cartiglia, N.; Parsons, J. A.; Ritz, S.; Sciulli, F.; Straub, P. B.; Wai, L.; Yang, S.; Zhu, Q.; Borzemski, P.; Chwastowski, J.; Eskreys, A.; Piotrzkowski, K.; Zachara, M.; Zawiejski, L.; Adamczyk, L.; Bednarek, B.; Jeleń, K.; Kisielewska, D.; Kowalski, T.; Rulikowska-Zarȩbska, E.; Suszycki, L.; ZajaÇ, J.; Kotański, A.; Przybycień, M.; Bauerdick, L. A.; Behrens, U.; Beier, H.; Bienlein, J. K.; Coldewey, C.; Deppe, O.; Desler, K.; Drews, G.; Flasiński, M.; Gilkinson, D. J.; Glasman, C.; Göttlicher, P.; Grosse-Knetter, J.; Gutjahr, B.; Hain, W.; Hasell, D.; Hessling, H.; Hultschig, H.; Iga, Y.; Joos, P.; Kasemann, M.; Klanner, R.; Koch, W.; Köpke, L.; Kötz, U.; Kowalski, H.; Labs, J.; Ladage, A.; Löhr, B.; Löwe, M.; Lüke, D.; Mańczak, O.; Ng, J. S.; Nickel, S.; Notz, D.; Ohrenberg, K.; Roco, M.; Rohde, M.; Roldán, J.; Schneekloth, U.; Schulz, W.; Selonke, F.; Stiliaris, E.; Surrow, B.; Voss, T.; Westphal, D.; Wolf, G.; Youngman, C.; Zhou, J. F.; Grabosch, H. J.; Kharchilava, A.; Leich, A.; Mattingly, M.; Meyer, A.; Schlenstedt, S.; Wulff, N.; Barbagli, G.; Pelfer, P.; Anzivino, G.; Maccarrone, G.; de Pasquale, S.; Votano, L.; Bamberger, A.; Eisenhardt, S.; Freidhof, A.; Söldner-Rembold, S.; Schroeder, J.; Trefzger, T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; Fleck, J. I.; Saxon, D. H.; Utley, M. L.; Wilson, A. S.; Dannemann, A.; Holm, U.; Horstmann, D.; Neumann, T.; Sinkus, R.; Wick, K.; Badura, E.; Burow, B. D.; Hagge, L.; Lohrmann, E.; Mainusch, J.; Milewski, J.; Nakahata, M.; Pavel, N.; Poelz, G.; Schott, W.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Gallo, E.; Harris, V. L.; Hung, B. Y.; Long, K. R.; Miller, D. B.; Morawitz, P. P.; Prinias, A.; Sedgbeer, J. K.; Whitfield, A. F.; Mallik, U.; McCliment, E.; Wang, M. Z.; Wang, S. M.; Wu, J. T.; Zhang, Y.; Cloth, P.; Filges, D.; An, S. H.; Hong, S. M.; Nam, S. W.; Park, S. K.; Suh, M. H.; Yon, S. H.; Imlay, R.; Kartik, S.; Kim, H.-J.; McNeil, R. R.; Metcalf, W.; Nadendla, V. K.; Barreiro, F.; Cases, G.; Graciani, R.; Hernández, J. M.; Hervás, L.; Labarga, L.; del Peso, J.; Puga, J.; Terron, J.; de Trocóniz, J. F.; Smith, G. R.; Corriveau, F.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Lim, J. N.; Matthews, C. G.; Patel, P. M.; Sinclair, L. E.; Stairs, D. G.; St. Laurent, M.; Ullmann, R.; Zacek, G.; Bashkirov, V.; Dolgoshein, B. A.; Stifutkin, A.; Bashindzhagyan, G. L.; Ermolov, P. F.; Gladilin, L. K.; Golubkov, Y. A.; Kobrin, V. D.; Kuzmin, V. A.; Proskuryakov, A. S.; Savin, A. A.; Shcheglova, L. M.; Solomin, A. N.; Zotov, N. P.; Botje, M.; Chlebana, F.; Dake, A.; Engelen, J.; de Kamps, M.; Kooijman, P.; Kruse, A.; Tiecke, H.; Verkerke, W.; Vreeswijk, M.; Wiggers, L.; de Wolf, E.; van Woudenberg, R.; Acosta, D.; Bylsma, B.; Durkin, L. S.; Honscheid, K.; Li, C.; Ling, T. Y.; McLean, K. W.; Murray, W. N.; Park, I. H.; Romanowski, T. A.; Seidlein, R.; Bailey, D. S.; Blair, G. A.; Byrne, A.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Daniels, D.; Devenish, R. C.; Harnew, N.; Lancaster, M.; Luffman, P. E.; Lindemann, L.; McFall, J. D.; Nath, C.; Noyes, V. A.; Quadt, A.; Uijterwaal, H.; Walczak, R.; Wilson, F. F.; Yip, T.; Abbiendi, G.; Bertolin, A.; Brugnera, R.; Carlin, R.; dal Corso, F.; de Giorgi, M.; Dosselli, U.; Limentani, S.; Morandin, M.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Bulmahn, J.; Butterworth, J. M.; Feild, R. G.; Oh, B. Y.; Whitmore, J. J.; D'Agostini, G.; Marini, G.; Nigro, A.; Tassi, E.; Hart, J. C.; McCubbin, N. A.; Prytz, K.; Shah, T. P.; Short, T. L.; Barberis, E.; Dubbs, T.; Heusch, C.; van Hook, M.; Hubbard, B.; Lockman, W.; Rahn, J. T.; Sadrozinski, H. F.-W.; Seiden, A.; Biltzinger, J.; Schwarzer, O.; Seifert, R. J.; Walenta, A. H.; Zech, G.; Abramowicz, H.; Briskin, G.; Dagan, S.; Levy, A.; Hasegawa, T.; Hazumi, M.; Ishii, T.; Kuze, M.; Mine, S.; Nagasawa, Y.; Nakao, M.; Suzuki, I.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Chiba, M.; Hamatsu, R.; Hirose, T.; Homma, K.; Kitamura, S.; Nakamitsu, Y.; Yamauchi, K.; Cirio, R.; Costa, M.; Ferrero, M. I.; Lamberti, L.; Maselli, S.; Peroni, C.; Sacchi, R.; Solano, A.; Staiano, A.; Dardo, M.; Bailey, D. C.; Bandyopadhyay, D.; Benard, F.; Brkic, M.; Crombie, M. B.; Gingrich, D. M.; Hartner, G. F.; Joo, K. K.; Levman, G. M.; Martin, J. F.; Orr, R. S.; Sampson, C. R.; Teuscher, R. J.; Catterall, C. D.; Jones, T. W.; Kaziewicz, P. B.; Lane, J. B.; Saunders, R. L.; Shulman, J.; Blankenship, K.; Kochocki, J.; Lu, B.; Mo, L. W.; Bogusz, W.; Charchuła, K.; Ciborowski, J.; Gajewski, J.; Grzelak, G.; Kasprzak, M.; Krzyżanowski, M.; Muchorowski, K.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Wróblewski, A. K.; Zakrzewski, J. A.; Żarnecki, A. F.; Adamus, M.; Eisenberg, Y.; Karshon, U.; Revel, D.; Zer-Zion, D.; Ali, I.; Badgett, W. F.; Behrens, B.; Dasu, S.; Fordham, C.; Foudas, C.; Goussiou, A.; Loveless, R. J.; Reeder, D. D.; Silverstein, S.; Smith, W. H.; Vaiciulis, A.; Wodarczyk, M.; Tsurugai, T.; Bhadra, S.; Cardy, M. L.; Fagerstroem, C.-P.; Frisken, W. R.; Furutani, K. M.; Khakzad, M.; Schmidke, W. B.

1995-08-01

Deep inelastic e-p scattering has been studied in both the charged current (CC) and neutral current (NC) reactions at momentum transfers squared Q2 above 400 GeV2 using the ZEUS detector at the HERA ep collider. The CC and NC total cross sections, the NC to CC cross section ratio, and the differential cross sections dσ/dQ2 are presented. From the Q2 dependence of the CC cross section, the mass term in the CC propagator is determined to be MW = 76+/-16+/-13 GeV.

Effects of silicon cross section and neutron spectrum on the radial uniformity in neutron transmutation doping.

PubMed

Kim, Haksung; Ho Pyeon, Cheol; Lim, Jae-Yong; Misawa, Tsuyoshi

2012-01-01

The effects of silicon cross section and neutron spectrum on the radial uniformity of a Si-ingot are examined experimentally with various neutron spectrum conditions. For the cross section effect, the numerical results using silicon single crystal cross section reveal good agreements with experiments within relative difference of 6%, whereas the discrepancy is approximately 20% in free-gas cross section. For the neutron spectrum effect, the radial uniformity in hard neutron spectrum is found to be more flattening than that in soft spectrum. Copyright © 2011 Elsevier Ltd. All rights reserved.

Electron-Impact Total Ionization Cross Sections of CH and C2H2

PubMed Central

Kim, Yong-Ki; Ali, M. Asgar; Rudd, M. Eugene

1997-01-01

Electron-impact total ionization cross sections for the CH radical and C2H2 (acetylene) have been calculated using the Binary-Encounter-Bethe (BEB) model. The BEB model combines the Mott cross section and the asymptotic form of the Bethe theory, and has been shown to generate reliable ionization cross sections for a large variety of molecules. The BEB cross sections for CH and C2H2 are in good agreement with the available experimental data from ionization thresholds to hundreds of eV in incident energies. PMID:27805116

Total reaction cross sections and neutron-removal cross sections of neutron-rich light nuclei measured by the COMBAS fragment-separator

NASA Astrophysics Data System (ADS)

Hue, B. M.; Isataev, T.; Erdemchimeg, B.; Artukh, A. G.; Aznabaev, D.; Davaa, S.; Klygin, S. A.; Kononenko, G. A.; Khuukhenkhuu, G.; Kuterbekov, K.; Lukyanov, S. M.; Mikhailova, T. I.; Maslov, V. A.; Mendibaev, K.; Sereda, Yu M.; Penionzhkevich, Yu E.; Vorontsov, A. N.

2017-12-01

Preliminary results of measurements of the total reaction cross sections σR and neutron removal cross section σ-xn for weakly bound 6He, 8Li, 9Be and 10Be nuclei at energy range (20-35) A MeV with 28Si target is presented. The secondary beams of light nuclei were produced by bombardment of the 22Ne (35 A MeV) primary beam on Be target and separated by COMBAS fragment-separator. In dispersive focal plane a horizontal slit defined the momentum acceptance as 1% and a wedge degrader of 200 μm Al was installed. The Bρ of the second section of the fragment-separator was adjusted for measurements in energy range (20-35) A MeV. Two-neutron removal cross sections for 6He and 10Be and one -neutron removal cross sections 8Li and 9Be were measured.

Bodies with noncircular cross sections and bank-to-turn missiles

NASA Technical Reports Server (NTRS)

Jackson, C. M., Jr.; Sawyer, W. C.

1986-01-01

An evaluation is made of prospective missile applications for noncircular cross section bodies, and of recent developments in bank-to-turn missile configuration aerodynamics. The discussion encompasses cross-flow analysis techniques, as well as study results obtained for bodies with elliptical and square cross sections and with variable cross sections. Attention is given to both the performance advantages and the stability and control problems of bank-to-turn missile configurations; the aerodynamic data presented for monoplanar configurations extend to those incorporating airbreathing propulsion systems.

Are pricing and reimbursement decision-making criteria aligned with public preferences regarding allocation principles in the Polish healthcare sector?

PubMed

Kolasa, Katarzyna

2014-10-01

Given growing interest in multicriteria decision making and multiple cost-effectiveness thresholds' approach, it was decided to investigate its usefulness in Poland. The pricing and reimbursement (P&R) regulations were reviewed and a cross-sectional survey was conducted amongst nurses. The study investigated whether P&R rules are aligned with the preferences of healthcare professional towards the concept of equity. The references to aversion to inequalities in health and capacity to benefit were recognized as the most and least important principle respectively by the group of nurses. Different weightings of health gain dependent on disease severity were accepted by half of the study's population. In the review of legal acts, references to capacity to benefit were frequently found. The opposite was registered for other concepts of equity. There is room for further improvement with respect to the alignment between the Polish P&R decision making criteria and public preferences regarding allocation principles.

Synthesis of carbon nanotubes using green plant extract as catalyst: unconventional concept and its realization

NASA Astrophysics Data System (ADS)

Tripathi, Nishant; Pavelyev, Vladimir; Islam, S. S.

2017-11-01

Green catalyst derived from plants, a cheap and abundant natural source, is used for the synthesis of multi-walled carbon nanotubes (MWNTs). The concept is unconventional and practically realized into existence by simple CVD growth while keeping away the potential hazards caused by metal catalyst on environment and living organisms. The notable points to mention of such growth are: (1) grown CNTs are free from toxic metal catalyst, (2) low growth temperature (575 °C) required and produced high yield vis-à-vis any other catalyst used so far reported, and (3) no need of expensive and complex systems for its synthesis. Besides, growth of SWNT as well as carbon nano-belts with hollow rectangular cross-section is observed when growth temperature increased to 800 °C, specifically, for the wall-nut extract. The samples were characterized by microscopic and spectroscopic analysis and the results verified our study. The present work provides innovative technique and may open up new avenues for CNTs synthesis and its applications.

Participant Perceptions of Character Concepts in a Physical Activity-Based Positive Youth Development Program.

PubMed

Riciputi, Shaina; McDonough, Meghan H; Ullrich-French, Sarah

2016-10-01

Physical activity-based positive youth development (PYD) programs often aim to foster character development. This study examined youth perspectives of character development curricula and the impact these activities have on their lives within and beyond the program. This case study examined youth from low-income families in a physical activity-based summer PYD program that integrated one character concept (respect, caring, responsibility, trust) in each of 4 weeks. Participants (N = 24) included a cross section of age, gender, ethnicity, and past program experience. Semi-structured interviews were analyzed using inductive thematic analysis and constant comparative methods. Thirteen themes were grouped in four categories: building highquality reciprocal relationships; intrapersonal improvement; moral reasoning and understanding; and rejection, resistance, and compliance. The findings provide participant-centered guidance for understanding youth personal and social development through physical activity in ways that are meaningful to participants, which is particularly needed for youth in low-income communities with limited youth programming.

Results of EVA/mobile transporter space station truss assembly tests

NASA Technical Reports Server (NTRS)

Watson, Judith J.; Heard, Walter L., Jr.; Bush, Harold G.; Lake, M. S.; Jensen, J. K.; Wallsom, R. E.; Phelps, J. E.

1988-01-01

Underwater neutral buoyance tests were conducted to evaluate the use of a Mobile Transporter concept in conjunction with EVA astronauts to construct the Space Station Freedom truss structure. A three-bay orthogonal tetrahedral truss configuration with a 15 foot square cross section was repeatedly assembled by a single pair of pressure suited test subjects working from the Mobile Transporter astronaut positioning devices (mobile foot restraints). The average unit assembly time (which included integrated installation of utility trays) was 27.6 s/strut, or 6 min/bay. The results of these tests indicate that EVA assembly of space station size structures can be significantly enhanced when using a Mobile Transporter equipped with astronaut positioning devices. Rapid assembly time can be expected and are dependent primarily on the rate of translation permissible for on-orbit operations. The concept used to demonstate integrated installation of utility trays requires minimal EVA handling and consequentially, as the results show, has little impact on overall assembly time.

Reactor Neutronics: Impact of Fissile Material

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heidet, F.; Hill, R. N.

Here, given a wide variety of reactor designs and fuel types, it can be difficult to identify the underlying cause of basic performance differences such as flux level and enrichment requirement. In this paper, using solely the definitions of the core multiplication factor and core power, simple relations have been derived allowing estimates of the flux ratio and fissile material concentration ratio for any reactor concept when 235U is replaced with 239Pu or vice-versa. These relations are functions of the neutron non-leakage probability, and one only needs to know number of neutrons emitted per fission, and the fission cross-section ratiomore » between the 235U system and the 239Pu system. It is found that for a reactor concept having significant leakage, the achievable flux level when using 239Pu as fissile material can be up to 45% larger than when using 235U as fissile material, and the required fissile concentration of 239Pu is up to 48% lower than that of 235U to achieve criticality.« less

Reactor Neutronics: Impact of Fissile Material

DOE PAGES

Heidet, F.; Hill, R. N.

2017-06-09

Here, given a wide variety of reactor designs and fuel types, it can be difficult to identify the underlying cause of basic performance differences such as flux level and enrichment requirement. In this paper, using solely the definitions of the core multiplication factor and core power, simple relations have been derived allowing estimates of the flux ratio and fissile material concentration ratio for any reactor concept when 235U is replaced with 239Pu or vice-versa. These relations are functions of the neutron non-leakage probability, and one only needs to know number of neutrons emitted per fission, and the fission cross-section ratiomore » between the 235U system and the 239Pu system. It is found that for a reactor concept having significant leakage, the achievable flux level when using 239Pu as fissile material can be up to 45% larger than when using 235U as fissile material, and the required fissile concentration of 239Pu is up to 48% lower than that of 235U to achieve criticality.« less

Effect of stiffness characteristics on the response of composite grid-stiffened structures

NASA Technical Reports Server (NTRS)

Ambur, Damodar R.; Rehfield, Lawrence W.

1991-01-01

A study of the effect of stiffness discontinuities and structural parameters on the response of continuous-filament grid-stiffened flat panels is presented. The buckling load degradation due to manufacturing-introduced stiffener discontinuities associated with a filament cut-and-add approach at the stiffener intersections is investigated. The degradation of buckling resistance in isogrid flat panels subjected to uni-axial compression and combined axial compression and shear loading conditions and induced damage is quantified using FEM. The combined loading case is the most critical one. Nonsolid stiffener cross sections, such as a foam-filled blade or hat with a 0-deg dominant cap, result in grid-stiffened structures that are structurally very efficient for wing and fuselage applications. The results of a study of the ability of grid-stiffened structural concepts to enhance the effective Poisson's ratio of a panel are presented. Grid-stiffened concepts create a highly effective Poisson's ratio, which can produce large camber deformations for certain elastic tailoring applications.

Cross sections for the dissociative attachment of electrons to NO

NASA Technical Reports Server (NTRS)

Krishnakumar, E.; Srivastava, S. K.

1988-01-01

Cross sections for the production of O(-) by electron attachment to NO are reported. It is found that the maximum value of the cross section is about 52 percent higher than the measurement of Rapp and Briglia (1965). Cross sections for the process of polar dissociation, e + NO yields N(+) + O(_), have also been measured, and the threshold energy for this process has been obtained.

Ground beetle communities in a mountain river subjected to restoration: The Raba River, Polish Carpathians.

PubMed

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.

Rock specific hydraulic fracturing and matrix acidizing to enhance a geothermal system — Concepts and field results

NASA Astrophysics Data System (ADS)

Zimmermann, Günter; Blöcher, Guido; Reinicke, Andreas; Brandt, Wulf

2011-04-01

Enhanced geothermal systems (EGS) are engineered reservoirs developed to extract economic amounts of heat from low permeability and/or porosity geothermal resources. To enhance the productivity of reservoirs, a site specific concept is necessary to actively make reservoir conditions profitable using specially adjusted stimulation treatments, such as multi fracture concepts and site specific well path design. The results of previously performed stimulation treatments in the geothermal research well GtGrSk4/05 at Groß Schönebeck, Germany are presented. The reservoir is located at a 4100-4300 m depth within the Lower Permian of the NE German Basin with a bottom-hole temperature of 150 °C. The reservoir rock is classified by two lithological units from bottom to top: volcanic rocks (andesitic rocks) and siliciclastics ranging from conglomerates to fine-grained sandstones (fluvial sediments). The stimulation treatments included multiple hydraulic stimulations and an acid treatment. In order to initiate a cross-flow from the sandstone layer, the hydraulic stimulations were performed in different depth sections (two in the sandstone section and one in the underlying volcanic section). In low permeability volcanic rocks, a cyclic hydraulic fracturing treatment was performed over 6 days in conjunction with adding quartz in low concentrations to maintain a sustainable fracture performance. Flow rates of up to 150 l/s were realized, and a total of 13,170 m 3 of water was injected. A hydraulic connection to the sandstone layer was successfully achieved in this way. However, monitoring of the water level in the offsetting well EGrSk3/90, which is 475 m apart at the final depth, showed a very rapid water level increase due to the stimulation treatment. This can be explained by a connected fault zone within the volcanic rocks. Two gel-proppant treatments were performed in the slightly higher permeability sandstones to obtain long-term access to the reservoir rocks. During each treatment, a total of 100 ton of high strength proppants was injected with 500 m 3 of cross-linked gel. The subsequent production test in conjunction with flowmeter logging showed an improvement of productivity by a factor of more than 4. Due to assumed residual drilling mud (constituents: calcite, dolomite, and aragonite) in the near-wellbore vicinity, an acid matrix stimulation was performed thereafter using a coil tubing unit. The following nitrogen lift test demonstrated another increase of productivity by 30-50% to an overall increase by a factor of 5.5-6.2.

Method Development for Binding Media Analysis in Painting Cross-Sections by Desorption Electrospray Ionization-Mass Spectrometry (DESI-MS).

PubMed

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.

Production cross sections of cosmic antiprotons in the light of new data from the NA61 and LHCb experiments

NASA Astrophysics Data System (ADS)

Korsmeier, Michael; Donato, Fiorenza; Di Mauro, Mattia

2018-05-01

The cosmic-ray flux of antiprotons is measured with high precision by the space-borne particle spectrometers AMS-02. Its interpretation requires a correct description of the dominant production process for antiprotons in our Galaxy, namely, the interaction of cosmic-ray proton and helium with the interstellar medium. In light of new cross section measurements by the NA61 experiment of p +p →p ¯+X and the first ever measurement of p +He →p ¯+X by the LHCb experiment, we update the parametrization of proton-proton and proton-nucleon cross sections. We find that the LHCb p He data constrain a shape for the cross section at high energies and show for the first time how well the rescaling from the p p channel applies to a helium target. By using p p , p He and p C data we estimate the uncertainty on the Lorentz invariant cross section for p +He →p ¯+X . We use these new cross sections to compute the source term for all the production channels, considering also nuclei heavier than He both in cosmic rays and the interstellar medium. The uncertainties on the total source term are up to ±20 % and slightly increase below antiproton energies of 5 GeV. This uncertainty is dominated by the p +p →p ¯+X cross section, which translates into all channels since we derive them using the p p cross sections. The cross sections to calculate the source spectra from all relevant cosmic-ray isotopes are provided in Supplemental Material. We finally quantify the necessity of new data on antiproton production cross sections, and pin down the kinematic parameter space which should be covered by future data.

Electron impact ionization cross sections of beryllium-tungsten clusters*

NASA Astrophysics Data System (ADS)

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

2016-01-01

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

Automatic arteriovenous crossing phenomenon detection on retinal fundus images

NASA Astrophysics Data System (ADS)

Hatanaka, Yuji; Muramatsu, Chisako; Hara, Takeshi; Fujita, Hiroshi

2011-03-01

Arteriolosclerosis is one cause of acquired blindness. Retinal fundus image examination is useful for early detection of arteriolosclerosis. In order to diagnose the presence of arteriolosclerosis, the physicians find the silver-wire arteries, the copper-wire arteries and arteriovenous crossing phenomenon on retinal fundus images. The focus of this study was to develop the automated detection method of the arteriovenous crossing phenomenon on the retinal images. The blood vessel regions were detected by using a double ring filter, and the crossing sections of artery and vein were detected by using a ring filter. The center of that ring was an interest point, and that point was determined as a crossing section when there were over four blood vessel segments on that ring. And two blood vessels gone through on the ring were classified into artery and vein by using the pixel values on red and blue component image. Finally, V2-to-V1 ratio was measured for recognition of abnormalities. V1 was the venous diameter far from the blood vessel crossing section, and V2 was the venous diameter near from the blood vessel crossing section. The crossing section with V2-to-V1 ratio over 0.8 was experimentally determined as abnormality. Twenty four images, including 27 abnormalities and 54 normal crossing sections, were used for preliminary evaluation of the proposed method. The proposed method was detected 73% of crossing sections when the 2.8 sections per image were mis-detected. And, 59% of abnormalities were detected by measurement of V1-to-V2 ratio when the 1.7 sections per image were mis-detected.

Misconceptions impairing the validity of the stopping power tables in the SRIM library and suggestions for doing better in the future

NASA Astrophysics Data System (ADS)

Wittmaack, Klaus

2016-08-01

The popular SRIM library delivers data and simulation codes for describing the slowing down of energetic atoms in matter. This study explored the validity of the tables containing cross sections for electronic and nuclear stopping together with the respective range parameters. The electronic stopping cross sections Se were produced, much like in previous and subsequent attempts of other groups, by bringing together the limited number of available experimental results in the form of ratios, r(Z1, He, υ) = Se(Z1, Z2, υ)/Se(He, Z2, υ). Z1 and Z2 denote the atomic numbers of projectiles (velocity υ) and target atoms, respectively. Reference data for He impact are available in reasonable volume only for about 15% of all solid targets; missing information has to be derived by interpolation. The concept of data evaluation is based on the assumption that the Bethe-Bloch (BB) theory, developed for bare projectiles, can serve as a guide at all velocities. For the purpose in question, the theory features an indispensible property: Z1 and Z2 appear as straight pre-factors, not in coupled form, Se,BB (υ) ∝ Z12 Z2 L (Z2, υ) , with L(Z2, υ) representing the stopping number. Therefore, Z2 and L(Z2, υ) cancel out when taking ratios for fixed Z1 so that data for arbitrary Z2 may be combined in one set of r-values to determine the best fit rfit(Z1, He, υ). The stopping cross sections of interest are then derived as Se(Z1, Z2, υ) = rfit(Z1, He, υ) Se(He, Z2, υ). At low energies these results were often refined, Se ⇒ Se,f, to account for experimental data that did not comply with the anticipated Z2-independent trend. Major findings and suggestions are as follows: (i) At high velocities, υ > 4Z12/3υ0 (Bohr velocity υ0), the SRIM predictions (have to) rely primarily on BB theory. (ii) At intermediate velocities, i.e., around the Bragg peak, SRIM appears to produce reasonable results (ca. ±15%). (iii) Below the Bragg peak the tabulated data often deviate strongly and inconsistently from the predictions of Lindhard-Scharff (LS) theory; they also exhibit various forms of exotic velocity dependence. These deviations are primarily due to the fact that the range of validity of BB theory is artificially extended to velocities at which the 'effective-charge' concept is assumed to be applicable. Coupled Z1,2 scaling as in theories of LS or Firsov would be much more appropriate. Overall, the electronic stopping cross sections by SRIM are of unpredictable value and often strongly misleading below 1 MeV/u. (iv) Another consequence of the tight link to the Z1,2 dependence of BB theory is that only 2 × 92 master sets of electronic stopping cross sections were required to generate all conceivable 89 × 92 tables from Se,f-ratios for elemental targets (the tables for H, He and Li projectiles are derived separately). The information contained in the SRIM library at large thus exhibits a highly redundant character. (v) The nuclear stopping cross sections Sn mirror the predictions of the universal potential due by Ziegler, Biersack and Littmark, which differ from alternative suggestions typically by less than 15%. With this uncertainty, range distributions may be calculated with the TRIM program of SRIM, but only at energies where Sn dominates so that uncertainties in Se play a minor role. (vi) As a side aspect, an example is presented illustrating the efforts required to identify incorrect experimental data, notably when respected authors are accountable. (vii) Other approaches to establish stopping power tables are shown to be subject to the same problems as SRIM. It is recommended to add a warning to all theses tables, informing users at which energies the data are likely to lack reliability. (viii) The currently unacceptable quality of Se,f-data below 1 MeV/u could be improved significantly in the future if the user friendly TRIM(SRIM) code were modified to allow simulations with a free choice of nuclear and electronic stopping cross sections. Researchers would thus be enabled to identify optimum input parameters for reproducing measured range distributions at energies at which Sn and Se are often of similar magnitude so that their contribution to the total energy loss is difficult to quantify without simulations.

Electron impact excitation of H2 - Rydberg band systems and the benchmark dissociative cross section for H Lyman-alpha

NASA Technical Reports Server (NTRS)

Shemansky, D. E.; Hall, D. T.; Ajello, J. M.

1985-01-01

The cross sections sigma R 1 (2p) for excitation of H Ly-alpha emission produced by electron impact on H2 is reexamined. A more accurate estimate for sigma R 1 (2p) is obtained based on Born approximation estimates of the H2 Rydberg system cross sections using measured relative excitation functions. The obtained value is (8.18 + or -1.2) x 10 to the -18th sq cm at 100 eV, a factor of 0.69 below the value universally applied to cross section measurements over the past decade. Cross sections for the H2 Rydberg systems fixed in magnitude by the Born approximation have also been obtained using experimentally determined excitation functions. Accurate analytic expressions for these cross sections allow the direct calculation of rate coefficients.

Creation of problem-dependent Doppler-broadened cross sections in the KENO Monte Carlo code

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hart, Shane W. D.; Celik, Cihangir; Maldonado, G. Ivan

2015-11-06

In this paper, we introduce a quick method for improving the accuracy of Monte Carlo simulations by generating one- and two-dimensional cross sections at a user-defined temperature before performing transport calculations. A finite difference method is used to Doppler-broaden cross sections to the desired temperature, and unit-base interpolation is done to generate the probability distributions for double differential two-dimensional thermal moderator cross sections at any arbitrarily user-defined temperature. The accuracy of these methods is tested using a variety of contrived problems. In addition, various benchmarks at elevated temperatures are modeled, and results are compared with benchmark results. Lastly, the problem-dependentmore » cross sections are observed to produce eigenvalue estimates that are closer to the benchmark results than those without the problem-dependent cross sections.« less

Measurement of neutrino-induced charged-current charged pion production cross sections on mineral oil at Eν˜1GeV

NASA Astrophysics Data System (ADS)

Aguilar-Arevalo, A. A.; Anderson, C. E.; Bazarko, A. O.; Brice, S. J.; Brown, B. C.; Bugel, L.; Cao, J.; Coney, L.; Conrad, J. M.; Cox, D. C.; Curioni, A.; Dharmapalan, R.; Djurcic, Z.; Finley, D. A.; Fleming, B. T.; Ford, R.; Garcia, F. G.; Garvey, G. T.; Grange, J.; Green, C.; Green, J. A.; Hart, T. L.; Hawker, E.; Imlay, R.; Johnson, R. A.; Karagiorgi, G.; Kasper, P.; Katori, T.; Kobilarcik, T.; Kourbanis, I.; Koutsoliotas, S.; Laird, E. M.; Linden, S. K.; Link, J. M.; Liu, Y.; Liu, Y.; Louis, W. C.; Mahn, K. B. M.; Marsh, W.; Mauger, C.; McGary, V. T.; McGregor, G.; Metcalf, W.; Meyers, P. D.; Mills, F.; Mills, G. B.; Monroe, J.; Moore, C. D.; Mousseau, J.; Nelson, R. H.; Nienaber, P.; Nowak, J. A.; Osmanov, B.; Ouedraogo, S.; Patterson, R. B.; Pavlovic, Z.; Perevalov, D.; Polly, C. C.; Prebys, E.; Raaf, J. L.; Ray, H.; Roe, B. P.; Russell, A. D.; Sandberg, V.; Schirato, R.; Schmitz, D.; Shaevitz, M. H.; Shoemaker, F. C.; Smith, D.; Soderberg, M.; Sorel, M.; Spentzouris, P.; Spitz, J.; Stancu, I.; Stefanski, R. J.; Sung, M.; Tanaka, H. A.; Tayloe, R.; Tzanov, M.; van de Water, R.; Wascko, M. O.; White, D. H.; Wilking, M. J.; Yang, H. J.; Zeller, G. P.; Zimmerman, E. D.

2011-03-01

Using a high-statistics, high-purity sample of νμ-induced charged current, charged pion events in mineral oil (CH2), MiniBooNE reports a collection of interaction cross sections for this process. This includes measurements of the CCπ+ cross section as a function of neutrino energy, as well as flux-averaged single- and double-differential cross sections of the energy and direction of both the final-state muon and pion. In addition, each of the single-differential cross sections are extracted as a function of neutrino energy to decouple the shape of the MiniBooNE energy spectrum from the results. In many cases, these cross sections are the first time such quantities have been measured on a nuclear target and in the 1 GeV energy range.

Communication: Electron ionization of DNA bases.

PubMed

Rahman, M A; Krishnakumar, E

2016-04-28

No reliable experimental data exist for the partial and total electron ionization cross sections for DNA bases, which are very crucial for modeling radiation damage in genetic material of living cell. We have measured a complete set of absolute partial electron ionization cross sections up to 500 eV for DNA bases for the first time by using the relative flow technique. These partial cross sections are summed to obtain total ion cross sections for all the four bases and are compared with the existing theoretical calculations and the only set of measured absolute cross sections. Our measurements clearly resolve the existing discrepancy between the theoretical and experimental results, thereby providing for the first time reliable numbers for partial and total ion cross sections for these molecules. The results on fragmentation analysis of adenine supports the theory of its formation in space.

Photon scattering cross sections of H2 and He measured with synchrotron radiation

NASA Technical Reports Server (NTRS)

Ice, G. E.

1977-01-01

Total (elastic + inelastic) differential photon scattering cross sections have been measured for H2 gas and He, using an X-ray beam. Absolute measured cross sections agree with theory within the probable errors. Relative cross sections (normalized to theory at large S) agree to better than one percent with theoretical values calculated from wave functions that include the effect of electron-electron Coulomb correlation, but the data deviate significantly from theoretical independent-particle (e.g., Hartree-Fock) results. The ratios of measured absolute He cross sections to those of H2, at any given S, also agree to better than one percent with theoretical He-to-H2 cross-section ratios computed from correlated wave functions. It appears that photon scattering constitutes a very promising tool for probing electron correlation in light atoms and molecules.

Electron impact ionisation cross section for organoplatinum compounds

NASA Astrophysics Data System (ADS)

Mahato, Dibyendu; Naghma, Rahla; Alam, Mohammad Jane; Ahmad, Shabbir; Antony, Bobby

2016-11-01

This article reports electron impact ionisation cross sections for platinum-based drugs viz., cisplatin (H6N2Cl2Pt), carboplatin (C6H12N2O4Pt), oxaliplatin (C8H14N2O4Pt), nedaplatin (C2H8N2O3Pt) and satraplatin (C10H22ClN2O4Pt) complexes used in the cancer chemotherapy. The multi-scattering centre spherical complex optical potential formalism is used to obtain the inelastic cross section for these large molecules upon electron impact. The ionisation cross section is derived from the inelastic cross section employing complex scattering potential-ionisation contribution method. Comparison is made with previous results, where ever available and overall a reasonable agreement is observed. This is the first attempt to report total ionisation cross sections for nedaplatin and satraplatin complexes.

Effect of wave function on the proton induced L XRP cross sections for 62Sm and 74W

NASA Astrophysics Data System (ADS)

Shehla, Kaur, Rajnish; Kumar, Anil; Puri, Sanjiv

2015-08-01

The Lk(k= 1, α, β, γ) X-ray production cross sections have been calculated for 74W and 62Sm at different incident proton energies ranging 1-5 MeV using theoretical data sets of different physical parameters, namely, the Li(i=1-3) sub-shell X-ray emission rates based on the Dirac-Fork (DF) model, the fluorescence and Coster Kronig yields based on the Dirac- Hartree-Slater (DHS) model and two sets the proton ionization cross sections based on the DHS model and the ECPSSR in order to assess the influence of the wave function on the XRP cross sections. The calculated cross sections have been compared with the measured cross sections reported in the recent compilation to check the reliability of the calculated values.

Comparative analysis of characteristic electron energy loss spectra and inelastic scattering cross-section spectra of Fe

NASA Astrophysics Data System (ADS)

Parshin, A. S.; Igumenov, A. Yu.; Mikhlin, Yu. L.; Pchelyakov, O. P.; Zhigalov, V. S.

2016-05-01

The inelastic electron scattering cross section spectra of Fe have been calculated based on experimental spectra of characteristic reflection electron energy loss as dependences of the product of the inelastic mean free path by the differential inelastic electron scattering cross section on the electron energy loss. It has been shown that the inelastic electron scattering cross-section spectra have certain advantages over the electron energy loss spectra in the analysis of the interaction of electrons with substance. The peaks of energy loss in the spectra of characteristic electron energy loss and inelastic electron scattering cross sections have been determined from the integral and differential spectra. It has been shown that the energy of the bulk plasmon is practically independent of the energy of primary electrons in the characteristic electron energy loss spectra and monotonically increases with increasing energy of primary electrons in the inelastic electron scattering cross-section spectra. The variation in the maximum energy of the inelastic electron scattering cross-section spectra is caused by the redistribution of intensities over the peaks of losses due to various excitations. The inelastic electron scattering cross-section spectra have been analyzed using the decomposition of the spectra into peaks of the energy loss. This method has been used for the quantitative estimation of the contributions from different energy loss processes to the inelastic electron scattering cross-section spectra of Fe and for the determination of the nature of the energy loss peaks.

Peeling Off Neutron Skins from Neutron-Rich Nuclei: Constraints on the Symmetry Energy from Neutron-Removal Cross Sections

NASA Astrophysics Data System (ADS)

Aumann, T.; Bertulani, C. A.; Schindler, F.; Typel, S.

2017-12-01

An experimentally constrained equation of state of neutron-rich matter is fundamental for the physics of nuclei and the astrophysics of neutron stars, mergers, core-collapse supernova explosions, and the synthesis of heavy elements. To this end, we investigate the potential of constraining the density dependence of the symmetry energy close to saturation density through measurements of neutron-removal cross sections in high-energy nuclear collisions of 0.4 to 1 GeV /nucleon . We show that the sensitivity of the total neutron-removal cross section is high enough so that the required accuracy can be reached experimentally with the recent developments of new detection techniques. We quantify two crucial points to minimize the model dependence of the approach and to reach the required accuracy: the contribution to the cross section from inelastic scattering has to be measured separately in order to allow a direct comparison of experimental cross sections to theoretical cross sections based on density functional theory and eikonal theory. The accuracy of the reaction model should be investigated and quantified by the energy and target dependence of various nucleon-removal cross sections. Our calculations explore the dependence of neutron-removal cross sections on the neutron skin of medium-heavy neutron-rich nuclei, and we demonstrate that the slope parameter L of the symmetry energy could be constrained down to ±10 MeV by such a measurement, with a 2% accuracy of the measured and calculated cross sections.

Semi-empirical scaling for ion–atom single charge exchange cross sections in the intermediate velocity regime

DOE PAGES

Friedman, B.; DuCharme, G.

2017-05-11

We present a semi-empirical scaling law for non-resonant ion–atom single charge exchange cross sections for collisions with velocities frommore » $${10}^{7}\\,{\\rm{t}}{\\rm{o}}\\,{10}^{9}\\,\\mathrm{cm}\\,{{\\rm{s}}}^{-1}$$ and ions with positive charge $$q\\lt 8$$. Non-resonant cross sections tend to have a velocity peak at collision velocities $$v\\lesssim 1\\ {\\rm{a}}{\\rm{u}}$$ 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, $${\\rm{\\Delta }}E$$, 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 $${v}_{{\\rm{m}}},{I}_{{\\rm{T}}},{Z}_{{\\rm{T}}},\\mathrm{and}\\ {Z}_{{\\rm{P}}}$$, where the $${Z}_{{\\rm{T}},{\\rm{P}}}$$ are the target and projectile atomic numbers. In conclusion, 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.« less

Blood lipid profiles and factors associated with dyslipidemia assessed by a point-of-care testing device in an outpatient setting: A large-scale cross-sectional study in Southern China.

PubMed

Zhang, Pei-dong; He, Lin-yun; Guo, Yang; Liu, Peng; Li, Gong-xin; Wang, Li-zi; Liu, Ying-feng

2015-06-01

To promote the concept of POCT and to investigate dyslipidemia in Guangzhou, China, we performed a study examining blood lipids assessed by POCT and reported factors associated with dyslipidemia. This multicenter, cross-sectional study enrolled outpatients from 9 Guangzhou hospitals from May through September 2013. After informed consent was obtained, the following information was collected: age; gender; the presence of diabetes mellitus, obesity, and hypertension as well as current use of cigarettes or alcohol. Patients were asked to fast for 8h before the blood examination performed on a POCT device, the CardioChek PA. Of 4012 patients enrolled (1544 males, 2468 females; mean age 60.35±9.41 years), 1993 (49.7%) patients had dyslipidemia, but only 101 (5.1%) took statins. The multivariate tests of associations between demographic variables, comorbidities, and the risk of having dyslipidemia found that the significant predictors of dyslipidemia were male gender, age ≥60 years, being a current smoker or alcohol drinker, and hypertension. Most dyslipidemia patients in Guangzhou remain untreated. POCT in China is feasible, and its widespread use might improve dyslipidemia awareness, treatment and control. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Numerical analysis of the flexible roll forming of an automotive component from high strength steel

NASA Astrophysics Data System (ADS)

Abeyrathna, B.; Abvabi, A.; Rolfe, B.; Taube, R.; Weiss, M.

2016-11-01

Conventional roll forming is limited to components with uniform cross-section; the recently developed flexible roll forming (FRF) process can be used to form components which vary in both width and depth. It has been suggested that this process can be used to manufacture automotive components from Ultra High Strength Steel (UHSS) which has limited tensile elongation. In the flexible roll forming process, the pre-cut blank is fed through a set of rolls; some rolls are computer-numerically controlled (CNC) to follow the 3D contours of the part and hence parts with a variable cross-section can be produced. This paper introduces a new flexible roll forming technique which can be used to form a complex shape with the minimum tooling requirements. In this method, the pre-cut blank is held between two dies and the whole system moves back and forth past CNC forming rolls. The forming roll changes its angle and position in each pass to incrementally form the part. In this work, the process is simulated using the commercial software package Copra FEA. The distribution of total strain and final part quality are investigated as well as related shape defects observed in the process. Different tooling concepts are used to improve the strain distribution and hence the part quality.

Exploratory analysis regarding the domain definitions for computer based analytical models

NASA Astrophysics Data System (ADS)

Raicu, A.; Oanta, E.; Barhalescu, M.

2017-08-01

Our previous computer based studies dedicated to structural problems using analytical methods defined the composite cross section of a beam as a result of Boolean operations with so-called ‘simple’ shapes. Using generalisations, in the class of the ‘simple’ shapes were included areas bounded by curves approximated using spline functions and areas approximated as polygons. However, particular definitions lead to particular solutions. In order to ascend above the actual limitations, we conceived a general definition of the cross sections that are considered now calculus domains consisting of several subdomains. The according set of input data use complex parameterizations. This new vision allows us to naturally assign a general number of attributes to the subdomains. In this way there may be modelled new phenomena that use map-wise information, such as the metal alloys equilibrium diagrams. The hierarchy of the input data text files that use the comma-separated-value format and their structure are also presented and discussed in the paper. This new approach allows us to reuse the concepts and part of the data processing software instruments already developed. The according software to be subsequently developed will be modularised and generalised in order to be used in the upcoming projects that require rapid development of computer based models.

Quality of Life of Adolescents With Transfusion-dependent Thalassemia and Their Siblings: A Cross-sectional Study.

PubMed

Ajij, Mohemmed; Pemde, Harish K; Chandra, Jagdish

2015-04-01

Transfusion-dependent thalassemia (TDT) and its treatment affect the physical, emotional, and social functioning, impairing the quality of life (QoL). There are few studies on QoL of adolescent with TDT. Its effect on their siblings' QoL has not been studied so far. In this cross-sectional study, 40 adolescents with TDT, 28 siblings, and 40 controls were studied to assess the QoL of adolescents thalassemics, and their siblings using the shorter version of World Health Organization Quality of Life instrument, the WHOQOL-BREF. Thalassemics had poor perception of their general health and scored significantly lower in all the subscales compared with the controls. Lowest mean subscale scores were for physical (57.7 vs. 72.4, P<0.001), and psychological domains (56.7 vs. 72.3, P<0.001). Their siblings also scored significantly less in environment domain. Prevalence of school dropout, short stature, and delayed puberty were significantly higher in thalassemics. Pretransfusion hemoglobin, age at onset of anemia, and chronological age were found to be significant predictors of total summary scores. This study showed that the concept of QoL is a cumulative reflection of individual and disease variables and highlights the negative impact of thalassemia on the patients' QoL and some aspects of their siblings' lives also.

Correlation-driven charge migration following double ionization and attosecond transient absorption spectroscopy

NASA Astrophysics Data System (ADS)

Hollstein, Maximilian; Santra, Robin; Pfannkuche, Daniela

2017-05-01

We theoretically investigate charge migration following prompt double ionization. Thereby, we extend the concept of correlation-driven charge migration, which was introduced by Cederbaum and coworkers for single ionization [Chem. Phys. Lett. 307, 205 (1999), 10.1016/S0009-2614(99)00508-4], to doubly ionized molecules. This allows us to demonstrate that compared to singly ionized molecules, in multiply ionized molecules, electron dynamics originating from electronic relaxation and correlation are particularly prominent. In addition, we also discuss how these correlation-driven electron dynamics might be evidenced and traced experimentally using attosecond transient absorption spectroscopy. For this purpose, we determine the time-resolved absorption cross section and find that the correlated electron dynamics discussed are reflected in it with exceptionally great detail. Strikingly, we find that features in the cross section can be traced back to electron hole populations and time-dependent partial charges and hence, can be interpreted with surprising ease. By taking advantage of element-specific core-to-valence transitions even atomic spatial resolution can be achieved. Thus, with the theoretical considerations presented, not only do we predict particularly diverse and correlated electron dynamics in molecules to follow prompt multiple ionization but we also identify a promising route towards their experimental investigation.

Geomorphological hazards and environmental impact: Assessment and mapping

NASA Astrophysics Data System (ADS)

Panizza, Mario

In five sections the author develops the methods for the integration of geomorphological concepts into Environmental Impact and Mapping. The first section introduces the concepts of Impact and Risk through the relationships between Geomorphological Environment and Anthropical Element. The second section proposes a methodology for the determination of Geomorphological Hazard and the identification of Geomorphological Risk. The third section synthesizes the procedure for the compilation of a Geomorphological Hazards Map. The fourth section outlines the concepts of Geomorphological Resource Assessment for the analysis of the Environmental Impact. The fifth section considers the contribution of geomorphological studies and mapping in the procedure for Environmental Impact Assessment.

A concept for holistic whole body MRI data analysis, Imiomics

PubMed Central

Malmberg, Filip; Johansson, Lars; Lind, Lars; Sundbom, Magnus; Ahlström, Håkan; Kullberg, Joel

2017-01-01

Purpose To present and evaluate a whole-body image analysis concept, Imiomics (imaging–omics) and an image registration method that enables Imiomics analyses by deforming all image data to a common coordinate system, so that the information in each voxel can be compared between persons or within a person over time and integrated with non-imaging data. Methods The presented image registration method utilizes relative elasticity constraints of different tissue obtained from whole-body water-fat MRI. The registration method is evaluated by inverse consistency and Dice coefficients and the Imiomics concept is evaluated by example analyses of importance for metabolic research using non-imaging parameters where we know what to expect. The example analyses include whole body imaging atlas creation, anomaly detection, and cross-sectional and longitudinal analysis. Results The image registration method evaluation on 128 subjects shows low inverse consistency errors and high Dice coefficients. Also, the statistical atlas with fat content intensity values shows low standard deviation values, indicating successful deformations to the common coordinate system. The example analyses show expected associations and correlations which agree with explicit measurements, and thereby illustrate the usefulness of the proposed Imiomics concept. Conclusions The registration method is well-suited for Imiomics analyses, which enable analyses of relationships to non-imaging data, e.g. clinical data, in new types of holistic targeted and untargeted big-data analysis. PMID:28241015

Is the shortened dental arch still a satisfactory option?

PubMed

Manola, M; Hussain, F; Millar, B J

2017-07-21

Aims Dental practitioners may hold the view that missing posterior teeth should be replaced to ensure a healthy masticatory system and satisfactory oral function. However, the shortened dental arch (SDA) concept is still in use, but after 35 years is it acceptable? This review searches the literature for the evidence and opinions regarding the suitability of the SDA as a current treatment modality.Methods Medline and PubMed databases were searched for relevant terms, all the abstracts were assessed and articles selected according to the pre-set exclusion and inclusion criteria.Results The search yielded 1,895 articles and after the assessment of the abstracts and application of the exclusion and inclusion criteria, 44 articles were selected for this review. These included 11 cohort studies, two longitudinal studies, two animal studies, three cross sectional studies, eight clinical studies and 18 case control studies. There appears to be a trend over the past three decades for more papers to be opposed to the SDA concept.Conclusion Evidence that the SDA causes pathology is lacking. Clinicians, healthcare authorities and patients have shown favourable attitudes towards the SDA and this continues, although there is an increase in studies opposing the concept and some are dissatisfied with this option. The concept remains viable particularly for the medically compromised patient or where restorations are considered unsuitable but further more specific studies are warranted.

Measured microwave scattering cross sections of three meteorite specimens

NASA Technical Reports Server (NTRS)

Hughes, W. E.

1972-01-01

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

Asymptotic form for the cross section for the Coulomb interacting rearrangement collisions.

NASA Technical Reports Server (NTRS)

Omidvar, K.

1973-01-01

It is shown that in a rearrangement collision leading to the formation of highly excited hydrogenlike states the cross section at high energies behaves as 1/n-squared, with n the principal quantum number, thus invalidating the Brinkman-Kramers approximation for large n. Similarly, in high-energy inelastic electron-hydrogenlike-atom collisions the exchange cross section for sufficiently large n dominates the direct excitation cross section.

Study of the angular coefficients and corresponding helicity cross sections of the W boson in hadron collisions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strologas, John; Errede, Steven; Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801

We present the standard model prediction for the eight angular coefficients of the W boson, which completely describes its differential cross section in hadron collisions. These coefficients are ratios of the W helicity cross sections and the total unpolarized cross section. We also suggest a technique to experimentally extract the coefficients, which we demonstrate in the Collins-Soper azimuthal-angle analysis.

Fragmentation Cross Sections of 290 and 400 MeV/nucleon 12C Beamson 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 0circ have been obtained for interactions of 290 MeV/nucleon and 400MeV/nucleon carbon beams with C, CH2, Al, Cu, Sn, and Pb targets. Thesebeams are relevant to cancer therapy, space radiation, and the productionof radioactive beams. We compare to previously published results using Cand CH2 targets at similar beam energies. Due to ambiguities arising fromthe presence of multiple fragments on many events, previous publicationshave reported only cross sections for B and Be fragments. In this work wehave extracted cross sections for all fragment species, using dataobtained at three distinct values of angular acceptance, supplementedmore » bydata taken with the detector stack placed off the beam axis. A simulationof the experiment with the PHITS Monte Carlo code shows fair agreementwith the data obtained with the large acceptance detectors, but agreementis poor at small acceptance. The measured cross sections are alsocompared to the predictions of the one-dimensional cross section modelsEPAX2 and NUCFRG2; the latter is presently used in NASA's space radiationtransport calculations. Though PHITS and NUCFRG2 reproduce thecharge-changing cross sections with reasonable accuracy, none of themodels is able to accurately predict the fragment cross sections for allfragment species and target materials.« less

Extracting Cross-Sectional Clinical Images Based on Their Principal Axes of Inertia

PubMed Central

Fan, Yuzhou; Djuric, Marija; Li, Zhiyu; Antonijevic, Djordje; Milenkovic, Petar; Sun, Yueyang; Li, Ruining

2017-01-01

Cross-sectional imaging is considered the gold standard in diagnosing a range of diseases. However, despite its widespread use in clinical practice and research, no widely accepted method is available to reliably match cross-sectional planes in several consecutive scans. This deficiency can impede comparison between cross-sectional images and ultimately lead to misdiagnosis. Here, we propose and demonstrate a method for finding the same imaging plane in images obtained during separate scanning sessions. Our method is based on the reconstruction of a “virtual organ” from which arbitrary cross-sectional images can be extracted, independent of the axis orientation in the original scan or cut; the key is to establish unique body coordinates of the organ from its principal axes of inertia. To verify our method a series of tests were performed, and the same cross-sectional plane was successfully extracted. This new approach offers clinicians access, after just a single scanning session, to the morphology and structure of a lesion through cross-sectional images reconstructed along arbitrary axes. It also aids comparable detection of morphological and structural changes in the same imaging plane from scans of the same patient taken at different times—thus potentially reducing the misdiagnosis rate when cross-sectional images are interpreted. PMID:29410714

Extracting Cross-Sectional Clinical Images Based on Their Principal Axes of Inertia.

PubMed

Fan, Yuzhou; Luo, Liangping; Djuric, Marija; Li, Zhiyu; Antonijevic, Djordje; Milenkovic, Petar; Sun, Yueyang; Li, Ruining; Fan, Yifang

2017-01-01

Cross-sectional imaging is considered the gold standard in diagnosing a range of diseases. However, despite its widespread use in clinical practice and research, no widely accepted method is available to reliably match cross-sectional planes in several consecutive scans. This deficiency can impede comparison between cross-sectional images and ultimately lead to misdiagnosis. Here, we propose and demonstrate a method for finding the same imaging plane in images obtained during separate scanning sessions. Our method is based on the reconstruction of a "virtual organ" from which arbitrary cross-sectional images can be extracted, independent of the axis orientation in the original scan or cut; the key is to establish unique body coordinates of the organ from its principal axes of inertia. To verify our method a series of tests were performed, and the same cross-sectional plane was successfully extracted. This new approach offers clinicians access, after just a single scanning session, to the morphology and structure of a lesion through cross-sectional images reconstructed along arbitrary axes. It also aids comparable detection of morphological and structural changes in the same imaging plane from scans of the same patient taken at different times-thus potentially reducing the misdiagnosis rate when cross-sectional images are interpreted.

Use of the Bethe equation for inner-shell ionization by electron impact

DOE Office of Scientific and Technical Information (OSTI.GOV)

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

2016-05-14

We analyzed calculated cross sections for K-, L-, and M-shell ionization by electron impact to determine the energy ranges over which these cross sections are consistent with the Bethe equation for inner-shell ionization. Our analysis was performed with K-shell ionization cross sections for 26 elements, with L-shell ionization cross sections for seven elements, L{sub 3}-subshell ionization cross sections for Xe, and M-shell ionization cross sections for three elements. The validity (or otherwise) of the Bethe equation could be checked with Fano plots based on a linearized form of the Bethe equation. Our Fano plots, which display theoretical cross sections andmore » available measured cross sections, reveal two linear regions as predicted by de Heer and Inokuti [in Electron Impact Ionization, edited by T. D. Märk and G. H. Dunn, (Springer-Verlag, Vienna, 1985), Chap. 7, pp. 232–276]. For each region, we made linear fits and determined values of the two element-specific Bethe parameters. We found systematic variations of these parameters with atomic number for both the low- and the high-energy linear regions of the Fano plots. We also determined the energy ranges over which the Bethe equation can be used.« less

Cross-Sectional Analysis of Longitudinal Mediation Processes.

PubMed

O'Laughlin, Kristine D; Martin, Monica J; Ferrer, Emilio

2018-01-01

Statistical mediation analysis can help to identify and explain the mechanisms behind psychological processes. Examining a set of variables for mediation effects is a ubiquitous process in the social sciences literature; however, despite evidence suggesting that cross-sectional data can misrepresent the mediation of longitudinal processes, cross-sectional analyses continue to be used in this manner. Alternative longitudinal mediation models, including those rooted in a structural equation modeling framework (cross-lagged panel, latent growth curve, and latent difference score models) are currently available and may provide a better representation of mediation processes for longitudinal data. The purpose of this paper is twofold: first, we provide a comparison of cross-sectional and longitudinal mediation models; second, we advocate using models to evaluate mediation effects that capture the temporal sequence of the process under study. Two separate empirical examples are presented to illustrate differences in the conclusions drawn from cross-sectional and longitudinal mediation analyses. Findings from these examples yielded substantial differences in interpretations between the cross-sectional and longitudinal mediation models considered here. Based on these observations, researchers should use caution when attempting to use cross-sectional data in place of longitudinal data for mediation analyses.

Single- and double-photoionization cross sections of atomic nitrogen from threshold to 31 A

NASA Technical Reports Server (NTRS)

Samson, James A. R.; Angel, G. C.

1990-01-01

The relative photoionization cross section of atomic nitrogen for the production of singly and doubly charged ions has been measured from 44.3 to 275 A and from 520 to 852 A. The results have been made absolute by normalization to one-half of the molecular nitrogen cross section at short wavelengths. The smoothed atomic nitrogen cross sections sigma can be accurately represented, at short wavelengths, by the equation sigma(Mb) = 36,700 x (E exp-2.3) as a function of the photon energy E (eV), thereby allowing the cross sections to be extrapolated to the nitrogen K edge at 31 A.

Analysis of the effectiveness of various cross-sections in large-span post-tensioned ceilings

NASA Astrophysics Data System (ADS)

Bednarz, K.

2018-03-01

The correct construction of large span, slim post-tensioned concrete slabs is conditioned by an appropriate cross-section selection. It is generally accepted that the thinnest slab can be constructed using the full cross-section as the largest compression stress storage. However, completely different cross-sections may help to overcome large spans. The paper presents the results of the computational analysis of several types of cross-sections (full, with internal relieving inserts and ribbed) in the application to a post-tensioned slab with a span of 15.0m. Based on the results presented, appropriate conclusions were drawn.

Calculation of the Coulomb Fission Cross Sections for Pb-Pb and Bi-Pb Interactions at 158 A GeV

NASA Technical Reports Server (NTRS)

Poyser, William J.; Ahern, Sean C.; Norbury, John W.; Tripathi, R. K.

2002-01-01

The Weizsacker-Williams (WW) method of virtual quanta is used to make approximate cross section calculations for peripheral relativistic heavy-ion collisions. We calculated the Coulomb fission cross sections for projectile ions of Pb-208 and Bi-209 with energies of 158 A GeV interacting with a Pb-208 target. We also calculated the electromagnetic absorption cross section for Pb-208 ion interacting as described. For comparison we use both the full WW method and a standard approximate WW method. The approximate WW method in larger cross sections compared to the more accurate full WW method.

Lidar cross-sections of soot fractal aggregates: Assessment of equivalent-sphere models

NASA Astrophysics Data System (ADS)

Ceolato, Romain; Gaudfrin, Florian; Pujol, Olivier; Riviere, Nicolas; Berg, Matthew J.; Sorensen, Christopher M.

2018-06-01

This work assesses the ability of equivalent-sphere models to reproduce the optical properties of soot aggregates relevant for lidar remote sensing, i.e. the backscattering and extinction cross sections. Lidar cross-sections are computed with a spectral discrete dipole approximation model over the visible-to-infrared (400-5000 nm) spectrum and compared with equivalent-sphere approximations. It is shown that the equivalent-sphere approximation, applied to fractal aggregates, has a limited ability to calculate such cross-sections well. The approximation should thus be used with caution for the computation of broadband lidar cross-sections, especially backscattering, at small and intermediate wavelengths (e.g. UV to visible).

Self-esteem, general and sexual self-concepts in blind people

PubMed Central

Salehi, Mehrdad; Azarbayejani, Abas; Shafiei, Katayoun; Ziaei, Tayebe; Shayegh, Bahar

2015-01-01

Background: People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. Materials and Methods: This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-concept using Eysenck self-esteem and Rogers’ self-concept questionnaires. The correlation between above two variables was measured using Statistical Package for the Social Sciences (SPSS) software by Pearson correlation test. Results: Mean [± standard deviation (SD)] age of patients was 30.9 ± 8 years. The mean (±SD) of general self-concept score was 11 ± 5.83. The mean (±SD) of self-esteem score was 16.62 ± 2.85. Pearson correlation results showed a significant positive correlation between self-esteem and general self-concept (r = 0.19, P = 0.025). The mean of sexual self-concept scores in five subscales (sexual anxiety, sexual self-efficacy, sexual self-esteem, sexual fear, and sexual depression) were correspondingly 11 ± 4.41, 19.53 ± 4.53, 12.96 ± 4.19, 13.48 ± 1.76, and 5.38 ± 2.36. Self-esteem and self-concept had significant positive correlation with sexual anxiety (r = 0.49; P < 0.001) (r = –.23; P < 0.001) and sexual fear (r = 0.25; P = 0.003) (r = 0.18; P = 0.02) and negative correlation with sexual self-efficacy (r = –0.26; P = 0.002) (r = –0.28; P = 0.001) and sexual-esteem (r = –0.34; P < 0.001) (r = –0.34; P < 0.001). Conclusion: Self-esteem and self-concept had significant correlation with sexual anxiety and sexual fear; and negative correlation with sexual self-efficacy and sexual-esteem. PMID:26929756

Self-esteem, general and sexual self-concepts in blind people.

PubMed

Salehi, Mehrdad; Azarbayejani, Abas; Shafiei, Katayoun; Ziaei, Tayebe; Shayegh, Bahar

2015-10-01

People with visual disability have lower self-esteem and social skills than sighted people. This study was designed to describe self-esteem and general and sexual self-concepts in blind people. This was a cross-sectional study, conducted in the Isfahan University of Medical Sciences in 2013-2014. In this study, 138 visually impaired people participated from Isfahan Province Welfare Organization and were interviewed for measuring of self-esteem and self-concept using Eysenck self-esteem and Rogers' self-concept questionnaires. The correlation between above two variables was measured using Statistical Package for the Social Sciences (SPSS) software by Pearson correlation test. Mean [± standard deviation (SD)] age of patients was 30.9 ± 8 years. The mean (±SD) of general self-concept score was 11 ± 5.83. The mean (±SD) of self-esteem score was 16.62 ± 2.85. Pearson correlation results showed a significant positive correlation between self-esteem and general self-concept (r = 0.19, P = 0.025). The mean of sexual self-concept scores in five subscales (sexual anxiety, sexual self-efficacy, sexual self-esteem, sexual fear, and sexual depression) were correspondingly 11 ± 4.41, 19.53 ± 4.53, 12.96 ± 4.19, 13.48 ± 1.76, and 5.38 ± 2.36. Self-esteem and self-concept had significant positive correlation with sexual anxiety (r = 0.49; P < 0.001) (r = -.23; P < 0.001) and sexual fear (r = 0.25; P = 0.003) (r = 0.18; P = 0.02) and negative correlation with sexual self-efficacy (r = -0.26; P = 0.002) (r = -0.28; P = 0.001) and sexual-esteem (r = -0.34; P < 0.001) (r = -0.34; P < 0.001). Self-esteem and self-concept had significant correlation with sexual anxiety and sexual fear; and negative correlation with sexual self-efficacy and sexual-esteem.

Introducing Economics.

ERIC Educational Resources Information Center

Federal Reserve Bank of Boston, MA.

The booklet outlines and presents examples of basic economics concepts. Objectives are to help elementary and secondary teachers introduce economic concepts in the classroom and to help teachers grasp some of the fundamentals of economics. The document is divided into seven sections. Each section presents concepts, offers three supporting…

Electron capture cross sections by O+ from atomic He

NASA Astrophysics Data System (ADS)

Joseph, Dwayne C.; Saha, Bidhan C.

2009-11-01

The adiabatic representation is used in both the quantal and semi classical molecular orbital close coupling methods (MOCC) to evaluate charge exchange cross sections. Our results show good agreement with experimental cross sections

Single-level resonance parameters fit nuclear cross-sections

NASA Technical Reports Server (NTRS)

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

1970-01-01

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

[Effect of resin infiltration on microhardness of artificial caries lesions].

PubMed

Liu, Yonghong; Deng, Hui; Tang, Longmei; Zhang, Zhiyong

2015-12-01

To compare the changes of enamel surface and cross-sectional microhardness of artificial caries immediately and after the twice demineralization through coating resin infiltration, fluoride varnish and fissure sealant. A total of forty bovine lower incisors enamel samples with artificial caries lesions by the demineralization liquid were used in the experiment. The specimens were then randomly divided into four groups as group A(resin infiltration), B(fluoride varnish), C (fissure sealant), D(control), 10 specimens in each group. The samples were sectioned vertically into two halves through the centre. One half of each sample the surface and cross-sectional microhardness was measured. The other half was put into demineralization liquid for 14 days, then the surface and cross-sectional microhardness was measured again. The cross section morphology of the samples was observed by scanning electron microscope. The surface of enamel had the highest microhardness value, and with the increase of cross- sectional depth, the microhardness value declined gradually. Variance analysis showed that the difference was statistically significant in the cross-section of different depth among the four groups(P<0.05). The microhardness values of the surface and the cross- section at 40 µm of each group in immediate measure showed the values were significantly higher in group A, B and C than in group D. There was no significant difference in the microhardness value of cross-section at 80 µm between group A[(324 ± 17) kg/mm(2)] and group C[(316 ± 20) kg/mm(2)], but they were significantly higher than group D. There was no significant difference between group B[(303 ± 13) kg/mm(2)] and group D[(294 ± 23) kg/mm(2)]. At 120 µm level, the microhardness value of group A was significantly higher than those of the other three groups. After the twice demineralization, the enamel surface microhardness value of the specimens was the same as the first measurement. In the cross-section at 40 µm level, the microhardness value was equal to the value of cross-section at 80 µm level of the first measurement. In the cross- section at 80 µm and 120 µm level, the microhardness value of group A was significantly higher than those of the other three groups. Resin infiltration can effectively strengthen microhardness of enamel surface and cross-section of different depth of artificial caries.

Examination of the 22C radius determination with interaction cross sections

NASA Astrophysics Data System (ADS)

Nagahisa, T.; Horiuchi, W.

2018-05-01

A nuclear radius of 22C is investigated with the total reaction cross sections at medium- to high-incident energies in order to resolve the radius puzzle in which two recent interaction cross-section measurements using 1H and 12C targets show the quite different radii. The cross sections of 22C are calculated consistently for these target nuclei within a reliable microscopic framework, the Glauber theory. To describe appropriately such a reaction involving a spatially extended nucleus, the multiple scattering processes within the Glauber theory are fully taken into account, that is, the multidimensional integration in the Glauber amplitude is evaluated using a Monte Carlo technique without recourse to the optical-limit approximation. We discuss the sensitivity of the spatially extended halo tail to the total reaction cross sections. The root-mean-square matter radius obtained in this study is consistent with that extracted from the recent cross-section measurement on 12C target. We show that the simultaneous reproduction of the two recent measured cross sections is not feasible within this framework.

Measurement of the Am 242 m neutron-induced reaction cross sections

DOE PAGES

Buckner, M. Q.; Wu, C. Y.; Henderson, R. A.; ...

2017-02-17

The neutron-induced reaction cross sections of 242mAm were measured at the Los Alamos Neutron Science Center using the Detector for Advanced Neutron-Capture Experiments array along with a compact parallel-plate avalanche counter for fission-fragment detection. A new neutron-capture cross section was determined, and the absolute scale was set according to a concurrent measurement of the well-known 242mAm(n,f) cross section. The (n,γ) cross section was measured from thermal energy to an incident energy of 1 eV at which point the data quality was limited by the reaction yield in the laboratory. Our new 242mAm fission cross section was normalized to ENDF/B-VII.1 tomore » set the absolute scale, and it agreed well with the (n,f) cross section from thermal energy to 1 keV. Lastly, the average absolute capture-to-fission ratio was determined from thermal energy to E n = 0.1 eV, and it was found to be 26(4)% as opposed to the ratio of 19% from the ENDF/B-VII.1 evaluation.« less

Mixed Legendre moments and discrete scattering cross sections for anisotropy representation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calloo, A.; Vidal, J. F.; Le Tellier, R.

2012-07-01

This paper deals with the resolution of the integro-differential form of the Boltzmann transport equation for neutron transport in nuclear reactors. In multigroup theory, deterministic codes use transfer cross sections which are expanded on Legendre polynomials. This modelling leads to negative values of the transfer cross section for certain scattering angles, and hence, the multigroup scattering source term is wrongly computed. The first part compares the convergence of 'Legendre-expanded' cross sections with respect to the order used with the method of characteristics (MOC) for Pressurised Water Reactor (PWR) type cells. Furthermore, the cross section is developed using piecewise-constant functions, whichmore » better models the multigroup transfer cross section and prevents the occurrence of any negative value for it. The second part focuses on the method of solving the transport equation with the above-mentioned piecewise-constant cross sections for lattice calculations for PWR cells. This expansion thereby constitutes a 'reference' method to compare the conventional Legendre expansion to, and to determine its pertinence when applied to reactor physics calculations. (authors)« less

Thermoelastic damping in microrings with circular cross-section

NASA Astrophysics Data System (ADS)

Li, Pu; Fang, Yuming; Zhang, Jianrun

2016-01-01

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

Measurement of 208Pb(n ,γ )209Pb Maxwellian averaged neutron capture cross section

NASA Astrophysics Data System (ADS)

Weissman, L.; Tessler, M.; Arenshtam, A.; Eliyahu, I.; Halfon, S.; Guerrero, C.; Kaizer, B.; Kijel, D.; Kreisel, A.; Palchan, T.; Paul, M.; Perry, A.; Schimel, G.; Silverman, I.; Shor, A.; Tamim, N.; Vaintraub, S.

2017-07-01

The doubly magic 208Pb nucleus is a bottleneck at the termination of the s -process path due to its very low neutron capture cross section. This cross section is also important for the decomposition of s , r processes and U/Th radiogenic decay contributions to the Pb-Bi solar abundances. The 208Pb(n ,γ )209Pb cross section was measured at the Soreq Applied Research Accelerator Facility Phase I using an intense quasi-Maxwellian neutron source produced by irradiation of the liquid-lithium target with a 1.5-mA continuous-wave proton beam at 1.94 MeV. The cross section was measured by counting the β activity from the irradiated lead target. The measurement allowed us to evaluate the Maxwellian averaged cross section (MACS) at 30 keV obtaining a value of 0.33(2) mb. This has been compared with the earlier activation and time-of-flight measurements found in the literature. The MACS cross-sectional value of the 63Cu(n ,γ )64Cu reaction was determined in the same experiment and is compared to a recent published value.

Multidimensional analysis of fast-spectrum material replacement measurements for systematic estimation of cross section uncertainties

NASA Technical Reports Server (NTRS)

Klann, P. G.; Lantz, E.; Mayo, W. T.

1973-01-01

A series of central core and core-reflector interface sample replacement experiments for 16 materials performed in the NASA heavy-metal-reflected, fast spectrum critical assembly (NCA) were analyzed in four and 13 groups using the GAM 2 cross-section set. The individual worths obtained by TDSN and DOT multidimensional transport theory calculations showed significant differences from the experimental results. These were attributed to cross-section uncertainties in the GAM 2 cross sections. Simultaneous analysis of the measured and calculated sample worths permitted separation of the worths into capture and scattering components which systematically provided fast spectrum averaged correction factors to the magnitudes of the GAM 2 absorption and scattering cross sections. Several Los Alamos clean critical assemblies containing Oy, Ta, and Mo as well as one of the NCA compositions were reanalyzed using the corrected cross sections. In all cases the eigenvalues were significantly improved and were recomputed to within 1 percent of the experimental eigenvalue. A comparable procedure may be used for ENDF cross sections when these are available.

Single and double capture in F9+ + Ar collisions: Comparison of total capture with capture occurring from the Ar K shell

NASA Astrophysics Data System (ADS)

La Mantia, David; Kumara, Nuwan; Kayani, Asghar; Simon, Anna; Tanis, John

2016-05-01

Total cross sections for single and double capture, as well as the corresponding cross sections for capture resulting in the emission of an Ar K x ray, were measured. This work was performed at Western Michigan University with the use of the tandem Van de Graaff accelerator. A 45 MeV beam of fully-stripped fluorine ions was collided with argon gas molecules in a differentially pumped cell. Surface barrier detectors were used to observe the charge changed projectiles and a Si(Li) x-ray detector, placed at 90o to the incident beam, were used to measure coincidences with Ar K x rays. The total capture cross sections are compared to previously measured cross sections in the existing literature. The coincidence cross sections, considerably smaller than the total cross sections, are found to be nearly equal for single and double capture in contrast to the total cross sections, which vary by about an order of magnitude. Possible reasons for this behavior are discussed. Supported in part by the NSF.

On the correlation of absorption cross-section with plasmonic color generation.

PubMed

Rezaei, Soroosh Daqiqeh; Ho, Jinfa; Ng, Ray Jia Hong; Ramakrishna, Seeram; Yang, Joel K W

2017-10-30

Through numerical simulations, we investigate the correlation between the absorption cross-section and the color saturation of plasmonic nanostructures of varying density. Understanding this correlation, enables the prediction of an optimal nanostructure separation, or combinations of different nanostructure sizes for plasmonic color printing applications. Here, we use metal-insulator-metal (MIM) aluminum nanostructures that support gap-plasmons. Large absorption cross-sections were observed that exceed twelve times the physical cross-section of the nanostructure disks. We derive a set of equations to determine the optimal separation for a periodic array using the absorption cross-section of an individual structure to realize saturated colors. Using the optimum pitch and enabled by the large absorption cross-sections of our structures, we employ color mixing strategies to realize a wider color gamut. The simulated color gamut exceeds the sRGB gamut for some colors, and includes dark tones. Color mixing using structures with large absorption cross-sections is a practical approach to generate a broad range of colors, in comparison to fabricating structures with continuously varying sizes.

Shell-model computed cross sections for charged-current scattering of astrophysical neutrinos off 40Ar

NASA Astrophysics Data System (ADS)

Kostensalo, Joel; Suhonen, Jouni; Zuber, K.

2018-03-01

Charged-current (anti)neutrino-40Ar cross sections for astrophysical neutrinos have been calculated. The initial and final nuclear states were calculated using the nuclear shell model. The folded solar-neutrino scattering cross section was found to be 1.78 (23 ) ×10-42cm2 , which is higher than what the previous papers have reported. The contributions from the 1- and 2- multipoles were found to be significant at supernova-neutrino energies, confirming the random-phase approximation (RPA) result of a previous study. The effects of neutrino flavor conversions in dense stellar matter (matter oscillations) were found to enhance the neutrino-scattering cross sections significantly for both the normal and inverted mass hierarchies. For the antineutrino scattering, only a small difference between the nonoscillating and inverted-hierarchy cross sections was found, while the normal-hierarchy cross section was 2-3 times larger than that of the nonoscillating cross section, depending on the adopted parametrization of the Fermi-Dirac distribution. This property of the supernova-antineutrino signal could probably be used to distinguish between the two hierarchies in megaton LAr detectors.

Differentiation between work and nonwork self-aspects as a predictor of presenteeism and engagement: cross-cultural differences.

PubMed

Garczynski, Amy M; Waldrop, Jessica S; Rupprecht, Elizabeth A; Grawitch, Matthew J

2013-10-01

Research on the work-life interface does not specifically account for how individuals cognitively conceptualize their work and nonwork lives in terms of the differentiation between work and nonwork self-aspects. In addition, no cross-cultural research examines self-concept differentiation in conjunction with employee outcomes of presenteeism and engagement, pointing to a need to study these relationships cross-culturally. Results of the current study revealed cultural differences in self-concept differentiation, engagement, mental presenteeism, and physical presenteeism. Indian participants reported lower levels of differentiation and higher levels of engagement, mental presenteeism, and physical presenteeism than American participants. Nationality interacted with self-concept differentiation to predict mental presenteeism, physical presenteeism, and engagement. Among Indian participants, self-concept differentiation did not impact scores on the other variables. However, among American participants, those lower in differentiation reported greater engagement, lower mental presenteeism, and lower physical presenteeism. These results have important implications for the study of the work-life interface, and they provide evidence that engagement and presenteeism may be culturally contingent.

[Design of cross-sectional anatomical model focused on drainage pathways of paranasal sinuses].

PubMed

Zha, Y; Lv, W; Gao, Y L; Zhu, Z Z; Gao, Z Q

2018-05-01

Objective: To design and produce cross-sectional anatomical models of paranasal sinuses for the purpose of demonstrating drainage pathways of each nasal sinus for the young doctors. Method: We reconstructed the three-dimensional model of sinuses area based on CT scan data, and divided it into 5 thick cross-sectional anatomy models by 4 coronal plane，which cross middle points of agger nasi cell, ethmoid bulla, posterior ethmoid sinuses and sphenoid sinus respectively. Then a 3D printerwas used to make anatomical cross-sectional anatomical models. Result: Successfully produced a digital 3D printing cross-sectional models of paranasal sinuses. Sinus drainage pathways were observed on the models. Conclusion: The cross-sectional anatomical models made by us can exactly and intuitively demonstrate the ostia of each sinus cell and they can help the young doctors to understand and master the key anatomies and relationships which are important to the endoscopic sinus surgery. Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.

Determining the partial photoionization cross-sections of ethyl radicals.

PubMed

FitzPatrick, B L; Maienschein-Cline, M; Butler, L J; Lee, S-H; Lin, J J

2007-12-13

Using a crossed laser-molecular beam scattering apparatus, these experiments photodissociate ethyl chloride at 193 nm and detect the Cl and ethyl products, resolved by their center-of-mass recoil velocities, with vacuum ultraviolet photoionization. The data determine the relative partial cross-sections for the photoionization of ethyl radicals to form C2H5+, C2H4+, and C2H3+ at 12.1 and 13.8 eV. The data also determine the internal energy distribution of the ethyl radical prior to photoionization, so we can assess the internal energy dependence of the photoionization cross-sections. The results show that the C2H4++H and C2H3++H2 dissociative photoionization cross-sections strongly depend on the photoionization energy. Calibrating the ethyl radical partial photoionization cross-sections relative to the bandwidth-averaged photoionization cross-section of Cl atoms near 13.8 eV allows us to use these data in conjunction with literature estimates of the Cl atom photoionization cross-sections to put the present bandwidth-averaged cross-sections on an absolute scale. The resulting bandwidth-averaged cross-section for the photoionization of ethyl radicals to C2H5+ near 13.8 eV is 8+/-2 Mb. Comparison of our 12.1 eV data with high-resolution ethyl radical photoionization spectra allows us to roughly put the high-resolution spectrum on the same absolute scale. Thus, one obtains the photoionization cross-section of ethyl radicals to C2H5+ from threshold to 12.1 eV. The data show that the onset of the C2H4++H dissociative photoionization channel is above 12.1 eV; this result offers a simple way to determine whether the signal observed in photoionization experiments on complex mixtures is due to ethyl radicals. We discuss an application of the results for resolving the product branching in the O+allyl bimolecular reaction.

A trend study of self-concept and mathematics achievement in a cross-cultural context

NASA Astrophysics Data System (ADS)

Wang, Jianjun

2007-12-01

The TIMSS 1995, 1999, and 2003 data have been gathered from Hong Kong before and after its sovereignty switch from the United Kingdom to China in 1997. Built on a reciprocal relation theory from the research literature, this investigation is designed to examine models of student self-concept and mathematics achievement during the political transition. Along with a perceived `brain drain' from the population migration, there was a non-monotonic change in the reciprocal relationship between self-concept and mathematics achievement. In addition, indicators of mathematics achievement and self-concept have demonstrated different linkages to the permanent emigration of Hong Kong residents with valued or desirable skills and qualifications. Interpretation of these empirical findings entails a need of enhancing cross-cultural understanding in mathematics education.

Research on the Cross Section Precision of High-strength Steel Tube with Rectangular Section in Rotary Draw Bending

NASA Astrophysics Data System (ADS)

Yang, Hongliang; Zhao, Hao; Xing, Zhongwen

2017-11-01

For the demand of energy conservation and security improvement, high-strength steel (HSS) is increasingly being used to produce safety related automotive components. However, cross-section distortion occurs easily in bending of HSS tube with rectangular section (RS), affecting the forming precision. HSS BR1500HS tube by rotary draw bending is taken as the study object and a description method of cross-section distortion is proposed in this paper. The influence on cross-section precision of geometric parameters including cross-section position, thickness of tube, bend radius etc. are studied by experiment. Besides, simulation of the rotary draw bending of HSS tube with rectangular section by ABAQUS are carried out and compared to the experiment. The results by simulation agree well with the experiment and show that the cross-section is approximately trapezoidal after distortion; the maximum of distortion exists at 45 ∼ 60° of the bending direction; and the absolute and relative distortion values increase with the decreasing of tube thickness or bending radius. Therefore, the results can provide a reference for the design of geometric parameters of HSS tube with rectangular section in rotary draw bending.

Interpretive geologic cross sections for the Death Valley regional flow system and surrounding areas, Nevada and California

USGS Publications Warehouse

Sweetkind, D.S.; Dickerson, R.P.; Blakely, R.J.; Denning, Paul

2001-01-01

This report presents a network of 28 geologic cross sections that portray subsurface geologic relations within the Death Valley regional ground-water system, a ground-water basin that encompasses a 3? x 3? area (approximately 70,000 km2) in southern Nevada and eastern California. The cross sections transect that part of the southern Great Basin that includes Death Valley, the Nevada Test Site, and the potential high-level nuclear waste underground repository at Yucca Mountain. The specific geometric relationships portrayed on the cross sections are discussed in the context of four general sub-regions that have stratigraphic similarities and general consistency of structural style: (1) the Nevada Test Site vicinity; (2) the Spring Mountains, Pahrump Valley and Amargosa Desert region; (3) the Death Valley region; and (4) the area east of the Nevada Test Site. The subsurface geologic interpretations portrayed on the cross sections are based on an integration of existing geologic maps, measured stratigraphic sections, published cross sections, well data, and geophysical data and interpretations. The estimated top of pre-Cenozoic rocks in the cross sections is based on inversion of gravity data, but the deeper parts of the sections are based on geologic conceptual models and are more speculative. The region transected by the cross sections includes part of the southern Basin and Range Province, the northwest-trending Walker Lane belt, the Death Valley region, and the northern Mojave Desert. The region is structurally complex, where a locally thick Tertiary volcanic and sedimentary section unconformably overlies previously deformed Proterozoic through Paleozoic rocks. All of these rocks have been deformed by complex Neogene ex-tensional normal and strike-slip faults. These cross sections form a three-dimensional network that portrays the interpreted stratigraphic and structural relations in the region; the sections form part of the geologic framework that will be incorporated in a complex numerical model of ground-water flow in the Death Valley region.

Morphology of Mesiobuccal Root Canals of Maxillary First Molars: a comparison of CBCT scanning and Cross-sectioning.

PubMed

Lyra, Carina Maria; Delai, Débora; Pereira, Keila Cristina Rausch; Pereira, Guy Martins; Pasternak Júnior, Bráulio; Oliveira, César Augusto Pereira

2015-10-01

The aim of this study was to evaluate the mesiobuccal root of maxillary first molars, according to the root canal configuration, prevalence and location of isthmuses at 3 and 6 mm from the apex, comparing cone-beam computed tomography (CBCT) analysis and cross sectioning of roots by thirds. Images of the mesiobuccal root of 100 maxillary first molars were acquired by CBCT and then roots were cross-sectioned into two parts, starting at 3 mm from the apex. Data were recorded and analyzed according to Weine's classification for root canal configuration, and Hsu and Kim's classification for isthmuses. In the analysis of CBCT images, 8 root canals were classified as type I, 57 as type II, 35 as type III. In the cross-sectioning technique, 19 root canals were classified as type I, 60 as type II, 20 as type III and 1 as type IV. The classification of isthmuses was predominantly type I in both CBCT and cross-sectioning evaluations for sections at 3 mm from the apex, while for sections at 6 mm from the apex, the classification of isthmuses was predominantly types V and II in CBCT and cross-sectioning evaluations, respectively. The cross-sectioning technique showed better results in detection of the internal morphology of root canals than CBCT scanning.

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

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ade, Brian J

2012-11-01

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

Bodies with noncircular cross sections and bank-to-turn missiles

NASA Technical Reports Server (NTRS)

Jackson, C. M., Jr.; Sawyer, W. C.

1992-01-01

A development status evaluation is presented for the aerodynamics of missile configurations with noncircular cross-sections and bank-to-turn maneuvering systems, giving attention to cases with elliptical and square cross-sections, as well as bodies with variable cross-sections. The assessment of bank-to-turn missile performance notes inherent stability/control problems. A summary and index are provided for aerodynamic data on monoplanar configurations, including those which incorporate airbreathing propulsion systems.

Measurement of the inclusive jet cross section at the CERN pp collider

NASA Astrophysics Data System (ADS)

Arnison, G.; Albrow, M. G.; Allkofer, O. C.; Astbury, A.; Aubert, B.; Bacci, C.; Batley, J. R.; Bauer, G.; Bettini, A.; Bézaguet, A.; Bock, R. K.; Bos, K.; Buckley, E.; Bunn, J.; Busetto, G.; Catz, P.; Cennini, P.; Centro, S.; Ceradini, F.; Ciapetti, G.; Cittolin, S.; Clarke, D.; Cline, D.; Cochet, C.; Colas, J.; Colas, P.; Corden, M.; Cox, G.; Dallman, D.; Dau, D.; Debeer, M.; Debrion, J. P.; Degiorgi, M.; della Negra, M.; Demoulin, M.; Denby, B.; Denegri, D.; Diciaccio, A.; Dobrzynski, L.; Dorenbosch, J.; Dowell, J. D.; Duchovni, E.; Edgecock, R.; Eggert, K.; Eisenhandler, E.; Ellis, N.; Erhard, P.; Faissner, H.; Fince Keeler, M.; Flynn, P.; Fontaine, G.; Frey, R.; Frühwirth, R.; Garvey, J.; Gee, D.; Geer, S.; Ghesquière, C.; Ghez, P.; Ghio, F.; Giacomelli, P.; Gibson, W. R.; Giraud-Héraud, Y.; Givernaud, A.; Gonidec, A.; Goodman, M.; Grassmann, H.; Grayer, G.; Guryn, W.; Hansl-Kozanecka, T.; Haynes, W.; Haywood, S. J.; Hoffmann, H.; Holthuizen, D. J.; Homer, R. J.; Homer, R. J.; Honma, A.; Jank, W.; Jimack, M.; Jorat, G.; Kalmus, P. I. P.; Karimäri, V.; Keeler, R.; Kenyon, I.; Kernan, A.; Kienzle, W.; Kinnunen, R.; Kozanecki, W.; Kroll, J.; Kryn, D.; Kyberd, P.; Lacava, F.; Laugier, J. P.; Lees, J. P.; Leuchs, R.; Levegrun, S.; Lévêque, A.; Levi, M.; Linglin, D.; Locci, E.; Long, K.; Markiewicz, T.; Markytan, M.; Martin, T.; Maurin, F.; McMahon, T.; Mendiburu, J.-P.; Meneguzzo, A.; Meyer, O.; Meyer, T.; Minard, M.-N.; Mohammadi, M.; Morgan, K.; Moricca, M.; Moser, H.; Mours, B.; Muller, Th.; Nandi, A.; Naumann, L.; Norton, A.; Paoluzi, L.; Pascoli, D.; Pauss, F.; Perault, C.; Piano Mortari, G.; Pietarinen, E.; Pigot, C.; Pimiä, M.; Pitman, D.; Placci, A.; Porte, J.-P.; Radermacher, E.; Ransdell, J.; Redelberger, T.; Reithler, H.; Revol, J. P.; Richman, J.; Rijssenbeek, M.; Rohlf, J.; Rossi, P.; Roberts, C.; Ruhm, W.; Rubbia, C.; Sajot, G.; Salvini, G.; Sass, J.; Sadoulet, B.; Samyn, D.; Savoy-Navarro, A.; Schinzel, D.; Schwartz, A.; Scott, W.; Scott, W.; Shah, T. P.; Sheer, I.; Siotis, I.; Smith, D.; Sobie, R.; Sphicas, P.; Strauss, J.; Streets, J.; Stubenrauch, C.; Summers, D.; Sumorok, K.; Szonczo, F.; Tao, C.; Ten Have, I.; Thompson, G.; Tscheslog, E.; Tuominiemi, J.; van Eijk, B.; Verecchia, P.; Vialle, J. P.; Virdee, T. S.; von der Schmitt, H.; von Schlippe, W.; Vrana, J.; Vuillemin, V.; Wahl, H. D.; Watkins, P.; Wilke, R.; Wilson, J.; Wingerter, I.; Wimpenny, S. J.; Wulz, C.-E.; Wyatt, T.; Yvert, M.; Zacharov, I.; Zaganidis, N.; Zanello, L.; Zotto, P.

1986-05-01

The inclusive jet cross section has been measured in the UA1 experiment at the CERN pp Collider at centre-of-mass energies √s = 546 GeV and √s = 630 eV. The cross sections are found to be consistent with QCD predictions, The observed change in the cross section with the centre-of-mass energy √s is accounted for in terms of xT scaling.