Science.gov

Sample records for neutron quality factor

  1. Neutron quality factor

    SciTech Connect

    1995-06-01

    Both the International Commission on Radiological Protection (ICRP) and the National Council on Radiation Protection and Measurements (NCRP) have recommended that the radiation quality weighting factor for neutrons (Q{sub n}, or the corresponding new modifying factor, w{sub R}) be increased by a value of two for most radiation protection practices. This means an increase in the recommended value for Q{sub n} from a nominal value of 10 to a nominal value of 20. This increase may be interpreted to mean that the biological effectiveness of neutrons is two times greater than previously thought. A decision to increase the value of Q{sub n} will have a major impact on the regulations and radiation protection programs of Federal agencies responsible for the protection of radiation workers. Therefore, the purposes of this report are: (1) to examine the general concept of {open_quotes}quality factor{close_quotes} (Q) in radiation protection and the rationale for the selection of specific values of Q{sub n}; and (2) to make such recommendations to the Federal agencies, as appropriate. This report is not intended to be an exhaustive review of the scientific literature on the biological effects of neutrons, with the aim of defending a particular value for Q{sub n}. Rather, the working group examined the technical issues surrounding the current recommendations of scientific advisory bodies on this matter, with the aim of determining if these recommendations should be adopted by the Federal agencies. Ultimately, the group concluded that there was no compelling basis for a change in Q{sub n}. The report was prepared by Federal scientists working under the auspices of the Science Panel of the Committee on Interagency Radiation Research and Policy Coordination (CIRRPC).

  2. Neutrons in proton pencil beam scanning: parameterization of energy, quality factors and RBE.

    PubMed

    Schneider, Uwe; Hälg, Roger A; Baiocco, Giorgio; Lomax, Tony

    2016-08-21

    The biological effectiveness of neutrons produced during proton therapy in inducing cancer is unknown, but potentially large. In particular, since neutron biological effectiveness is energy dependent, it is necessary to estimate, besides the dose, also the energy spectra, in order to obtain quantities which could be a measure of the biological effectiveness and test current models and new approaches against epidemiological studies on cancer induction after proton therapy. For patients treated with proton pencil beam scanning, this work aims to predict the spatially localized neutron energies, the effective quality factor, the weighting factor according to ICRP, and two RBE values, the first obtained from the saturation corrected dose mean lineal energy and the second from DSB cluster induction. A proton pencil beam was Monte Carlo simulated using GEANT. Based on the simulated neutron spectra for three different proton beam energies a parameterization of energy, quality factors and RBE was calculated. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed parameterizations in order to calculate the spatially localized neutron energy, quality factors and RBE for each treated patient. The parameterization represents the simple quantification of neutron energy in two energy bins and the quality factors and RBE with a satisfying precision up to 85 cm away from the proton pencil beam when compared to the results based on 3D Monte Carlo simulations. The root mean square error of the energy estimate between Monte Carlo simulation based results and the parameterization is 3.9%. For the quality factors and RBE estimates it is smaller than 0.9%. The model was successfully integrated into the PSI treatment planning system. It was found that the parameterizations for neutron energy, quality factors and RBE were independent of proton energy in the investigated energy range of interest for proton therapy. The pencil beam algorithm has

  3. Neutrons in proton pencil beam scanning: parameterization of energy, quality factors and RBE

    NASA Astrophysics Data System (ADS)

    Schneider, Uwe; Hälg, Roger A.; Baiocco, Giorgio; Lomax, Tony

    2016-08-01

    The biological effectiveness of neutrons produced during proton therapy in inducing cancer is unknown, but potentially large. In particular, since neutron biological effectiveness is energy dependent, it is necessary to estimate, besides the dose, also the energy spectra, in order to obtain quantities which could be a measure of the biological effectiveness and test current models and new approaches against epidemiological studies on cancer induction after proton therapy. For patients treated with proton pencil beam scanning, this work aims to predict the spatially localized neutron energies, the effective quality factor, the weighting factor according to ICRP, and two RBE values, the first obtained from the saturation corrected dose mean lineal energy and the second from DSB cluster induction. A proton pencil beam was Monte Carlo simulated using GEANT. Based on the simulated neutron spectra for three different proton beam energies a parameterization of energy, quality factors and RBE was calculated. The pencil beam algorithm used for treatment planning at PSI has been extended using the developed parameterizations in order to calculate the spatially localized neutron energy, quality factors and RBE for each treated patient. The parameterization represents the simple quantification of neutron energy in two energy bins and the quality factors and RBE with a satisfying precision up to 85 cm away from the proton pencil beam when compared to the results based on 3D Monte Carlo simulations. The root mean square error of the energy estimate between Monte Carlo simulation based results and the parameterization is 3.9%. For the quality factors and RBE estimates it is smaller than 0.9%. The model was successfully integrated into the PSI treatment planning system. It was found that the parameterizations for neutron energy, quality factors and RBE were independent of proton energy in the investigated energy range of interest for proton therapy. The pencil beam algorithm has

  4. Quality factors

    SciTech Connect

    Kerr, G.D.

    1986-01-01

    The quality factor, Q, is a dimensionless modifier used in converting absorbed dose, expressed in rads (or grays), to dose equivalent, expressed in rems (or seiverts). The dose equivalent is used in radiation protection to account for the biological effectiveness of different kinds of radiation. The quality factor is related to both the linear energy transfer (LET) and relative biological effectiveness (RBE). The RBE's obtained from biological experiments depend in a complex way on the observed biological effect, the specific test organism, and the experimental conditions. Judgement is involved, therefore, in the choice of the quality factor. Questions regarding the adequacy of current Q values for neutrons were raised first in a 1980 statement by the National Council on Radiation Protection (NCRP) and later in a 1985 statement by the International Commission on Radiological Protection (ICRP). In 1980, the NCRP alerted the technical community to possible future increases between a factor of three and ten in the Q for neutrons, and in 1985, the ICRP suggested an increase by a factor of two in Q for neutrons. Both the ICRP and NRCP are now recommending essentially the same guidance with regard to Q for neutrons: an increase by a factor of two. The Q for neutrons is based on a large, albeit unfocused, body of experimental data. In spite of the lack of focus, the data supporting a change in the neutron quality factor are substantial. However, the proposed doubling of Q for neutrons is clouded by other issues regarding its application. 33 refs., 4 figs., 6 tabs.

  5. Photon and neutron dose contributions and mean quality factors in phantoms of different size irradiated by monoenergetic neutrons

    SciTech Connect

    Dietze, G.; Siebert, B.R.L.

    1994-10-01

    The International Commission on Radiological Protection (ICRP) in its Publication 60 introduced important changes in the concept of risk-related quantities. For external neutron radiation in particular the introduction of the equivalent dose with the radiation weighting factor w{sub R} instead of the dose equivalent concept with the quality factor Q(L) has many consequences. The value of w{sub R} is defined by the external neutron radiation field, while the radiation quality in the phantom depends on the radiation field at the position of interest and hence on the size of and the position in the phantom. It has been investigated to what extent the size of the phantom influences the mean irradiation quality in the phantoms. For incident monoenergetic neutrons, mean photon dose contributions and mean quality factors have been calculated. Results are presented for various phantoms which characterize the conditions for a mouse, a rat, the ICRU sphere and a human body. 9 refs., 2 figs., 1 tab.

  6. Options for the modified radiation weighting factor of neutrons.

    PubMed

    Kellerer, A M; Leuthold, G; Mares, V; Schraube, H

    2004-01-01

    The recent ICRP Report 92 has noted that the current radiation weighting factor, wR, depends on the energy of the incident neutrons in a manner that differs substantially from the dependence, which results from the current convention, QL. At all neutron energies, but most conspicuously below 1 MeV, the values of wR exceed those of the effective quality factor, qE. The discrepancy is largely due to the fact that--in the absence of computed values of the effective quality factor for neutrons--wR has been patterned after the values of the ambient quality factor, which accounts insufficiently for the low-linear energy transfer (LET) gamma ray component from neutron capture in the human body. There are different options to remove the discrepancy. Option 1 is to reduce wR substantially at all neutron energies to make it equal to qE for a standard condition, such as isotropic incidence of the neutrons. Since such a reduction may cause problems in those countries where the current wR values are already legally implemented, ICRP 92 has proposed what is here termed Option 2. It recommended to replace QL by the increased value 1.6 QL - 0.6 and, accordingly, to make the radiation weighting factor equal to 1.6 qE - 0.6. With Option 2 the radiation weighting factor needs to be decreased appreciably at low neutron energies, but for fission neutron spectra the overall changes are minor. To guide--regardless which option is chosen--the selection of the numerical values, the effective quality factor, qE, is computed here for different directional distributions of neutrons incident on the anthropomorphic phantoms ADAM and EVA. None of the sex averaged numerical values is found to deviate much from those for isotropic incidence. Isotropic incidence can, thus, be used as an adequate standard condition. A numerical approximation is proposed for the standard qE that is nearly equivalent to a formula invoked by ICRP 92, but is somewhat simpler and provides realistic values of qE even for

  7. Analyzing the effect of geometric factors on designing neutron radiography system.

    PubMed

    Amini, Moharam; Fadaei, Amir Hosein; Gharib, Morteza

    2015-11-01

    Neutron radiography is one of the main applications of research reactors. It is a powerful tool to conduct nondestructive testing of materials. The parameters that affect the quality of a radiographic image must be considered during the design of a neutron radiography system. Hence, this study aims to investigate the effect of geometric factors on the quality of the neutron radiography system. The results show that the performance of the mentioned system can be increased by regulating the geometric factors. PMID:26343340

  8. Neutron charge radius and the neutron electric form factor

    SciTech Connect

    Gentile, T. R.; Crawford, C. B.

    2011-05-15

    For nearly forty years, the Galster parametrization has been employed to fit existing data for the neutron electric form factor, G{sub E}{sup n}, vs the square of the four-momentum transfer, Q{sup 2}. Typically this parametrization is constrained to be consistent with experimental data for the neutron charge radius. However, we find that the Galster form does not have sufficient freedom to accommodate reasonable values of the radius without constraining or compromising the fit. In addition, the G{sub E}{sup n} data are now at sufficient precision to motivate a two-parameter fit (or three parameters if we include thermal neutron data). Here we present a modified form of a two-dipole parametrization that allows this freedom and fits both G{sub E}{sup n} (including recent data at both low and high four-momentum transfer) and the charge radius well with simple, well-defined parameters. Analysis reveals that the Galster form is essentially a two-parameter approximation to the two-dipole form but becomes degenerate if we try to extend it naturally to three parameters.

  9. Factors Affecting Medical Service Quality

    PubMed Central

    MOSADEGHRAD, Ali Mohammad

    2014-01-01

    Abstract Background A better understanding of factors influencing quality of medical service can pinpoint better strategies for quality assurance in medical services. This study aimed to identify factors affecting the quality of medical services provided by Iranian physicians. Methods Exploratory in-depth individual interviews were conducted with sixty-four physicians working in various medical institutions in Iran. Results Individual, organizational and environmental factors enhance or inhibit the quality of medical services. Quality of medical services depends on the personal factors of the physician and patient, and factors pertaining to the healthcare setting and the broader environment. Conclusion Differences in internal and external factors such as availability of resources, patient cooperation and collaboration among providers affect the quality of medical services and patient outcomes. Supportive leadership, proper planning, education and training and effective management of resources and processes improve the quality of medical services. This article contributes to healthcare theory and practice by developing a conceptual framework for understanding factors that influence medical services quality. PMID:26060745

  10. Electric Form Factor of the Neutron

    SciTech Connect

    Feuerbach, Robert

    2007-10-13

    Recent polarization-based precision measurements of the nucleons' elastic electric form factors have led to surprising results. The measurement of the ratio of the proton's electromagnetic form factors, $\\mu_p G_E^p/G_M^p$, was found to drop nearly linearly with $Q^2$ out to at least $5 \\mathrm{GeV}^2$, inconsistent with the older Rosenbluth-type experiments. A recent measurement of $G_E^n$, the neutron's electric form-factor saw $G_E^n$ does not fall off as quickly as commonly expected up to $Q^2 \\approx 1.5 \\mathrm{GeV}^2$. Extending this study, a precision measurement of $G_E^n$ up to $Q^2=3.5 \\mathrm{GeV}^2$ was completed in Hall A at Jefferson Lab. The ratio $G_E^n/G_M^n$ was measured through the beam-target asymmetry $A_\\perp$ of electrons quasi-elastically scattered off polarized neutrons in the reaction ${}^{3}\\overrightarrow{He}(\\overrightarrow{e},e' n)$. The experiment took full advantage of the electron beam, recent target developments, as well as two detectors new to Jefferson Lab. The measurement used the accelerator's 100\\% duty-cycle high-polarization (typically 84\\%) electron beam and a new, hybrid optically-pumped polarized ${}^{3}\\overrightarrow{He}$ target which achieved in-beam polarizations in excess of 50\\%. A medium acceptance (80msr) open-geometry magnetic spectrometer (BigBite) detected the scattered electron, while a geometrically matched neutron detector observed the struck neutron. Preliminary results from this measurement will be discussed and compared to modern calculations of $G_E^n$.

  11. Factors influencing healthcare service quality

    PubMed Central

    Mosadeghrad, Ali Mohammad

    2014-01-01

    Background: The main purpose of this study was to identify factors that influence healthcare quality in the Iranian context. Methods: Exploratory in-depth individual and focus group interviews were conducted with 222 healthcare stakeholders including healthcare providers, managers, policy-makers, and payers to identify factors affecting the quality of healthcare services provided in Iranian healthcare organisations. Results: Quality in healthcare is a production of cooperation between the patient and the healthcare provider in a supportive environment. Personal factors of the provider and the patient, and factors pertaining to the healthcare organisation, healthcare system, and the broader environment affect healthcare service quality. Healthcare quality can be improved by supportive visionary leadership, proper planning, education and training, availability of resources, effective management of resources, employees and processes, and collaboration and cooperation among providers. Conclusion: This article contributes to healthcare theory and practice by developing a conceptual framework that provides policy-makers and managers a practical understanding of factors that affect healthcare service quality. PMID:25114946

  12. Calibration factors for the SNOOPY NP-100 neutron dosimeter

    NASA Astrophysics Data System (ADS)

    Moscu, D. F.; McNeill, F. E.; Chase, J.

    2007-10-01

    Within CANDU nuclear power facilities, only a small fraction of workers are exposed to neutron radiation. For these individuals, roughly 4.5% of the total radiation equivalent dose is the result of exposure to neutrons. When this figure is considered across all workers receiving external exposure of any kind, only 0.25% of the total radiation equivalent dose is the result of exposure to neutrons. At many facilities, the NP-100 neutron dosimeter, manufactured by Canberra Industries Incorporated, is employed in both direct and indirect dosimetry methods. Also known as "SNOOPY", these detectors undergo calibration, which results in a calibration factor relating the neutron count rate to the ambient dose equivalent rate, using a standard Am-Be neutron source. Using measurements presented in a technical note, readings from the dosimeter for six different neutron fields in six source-detector orientations were used, to determine a calibration factor for each of these sources. The calibration factor depends on the neutron energy spectrum and the radiation weighting factor to link neutron fluence to equivalent dose. Although the neutron energy spectra measured in the CANDU workplace are quite different than that of the Am-Be calibration source, the calibration factor remains constant - within acceptable limits - regardless of the neutron source used in the calibration; for the specified calibration orientation and current radiation weighting factors. However, changing the value of the radiation weighting factors would result in changes to the calibration factor. In the event of changes to the radiation weighting factors, it will be necessary to assess whether a change to the calibration process or resulting calibration factor is warranted.

  13. Spectral correction factors for conventional neutron dosemeters used in high-energy neutron environments.

    PubMed

    Lee, K W; Sheu, R J

    2015-04-01

    High-energy neutrons (>10 MeV) contribute substantially to the dose fraction but result in only a small or negligible response in most conventional moderated-type neutron detectors. Neutron dosemeters used for radiation protection purpose are commonly calibrated with (252)Cf neutron sources and are used in various workplace. A workplace-specific correction factor is suggested. In this study, the effect of the neutron spectrum on the accuracy of dose measurements was investigated. A set of neutron spectra representing various neutron environments was selected to study the dose responses of a series of Bonner spheres, including standard and extended-range spheres. By comparing (252)Cf-calibrated dose responses with reference values based on fluence-to-dose conversion coefficients, this paper presents recommendations for neutron field characterisation and appropriate correction factors for responses of conventional neutron dosemeters used in environments with high-energy neutrons. The correction depends on the estimated percentage of high-energy neutrons in the spectrum or the ratio between the measured responses of two Bonner spheres (the 4P6_8 extended-range sphere versus the 6″ standard sphere). PMID:25280480

  14. Human factors and quality improvement.

    PubMed

    Handyside, James; Suresh, Gautham

    2010-03-01

    Human factors analysis (HFE) presents a formidable contribution to quality improvement (QI) in the neonatal intensive care unit (NICU). The science behind the fundamental principles concerning the design of work systems that match the needs of the people who work in them is sound and is applied widely in other safety critical situations. Early application of HFE in NICUs has shown the usefulness of these methods for frontline teams working to improve quality, reliability, and safety. The inclusion of human factors considerations in the design of structure and process has the potential to improve outcomes for patients and families and to improve the comfort and usability of work systems for providers who work in them. New technologies and continual change must be informed and designed through the application of HFE methods and principles to realize the full potential of QI. PMID:20363451

  15. Towards in vivo monitoring of neutron distributions for quality control of BNCT

    NASA Astrophysics Data System (ADS)

    Verbakel, W. F. A. R.; Hideghety, K.; Morrissey, J.; Sauerwein, W.; Stecher-Rasmussen, F.

    2002-04-01

    Dose delivery in boron neutron capture therapy (BNCT) is complex because several components contribute to the dose absorbed in tissue. This dose is largely determined by local boron concentration, thermal neutron distribution and patient positioning. In vivo measurements of these factors would considerably improve quality control and safety. During therapy, a γ-ray telescope measures the γ-rays emitted following neutron capture by hydrogen and boron in a small volume of the head of a patient. Scans of hydrogen γ-ray emissions could be used to verify the actual distribution of thermal neutrons during neutron irradiation. The method was first tested on different phantoms. These measurements showed good agreement with calculations based on thermal neutron distributions derived from a treatment planning program and from Monte Carlo N-particle (MCNP) simulations. Next, the feasibility of telescope scans during patient irradiation therapy was demonstrated. Measurements were reproducible between irradiation fractions. In theory, this method can be used to verify the positioning of the patient in vivo and the delivery of thermal neutrons in tissue. However, differences between measurements and calculations based on a routine treatment planning program were observed. These differences could be used to refine the treatment planning. Further developments will be necessary for this method to become a standard quality control system.

  16. Parameters affecting image quality with Time-Resolved Optical Integrative Neutron (TRION) detector

    NASA Astrophysics Data System (ADS)

    Mor, I.; Vartsky, D.; Feldman, G.; Dangendorf, V.; Bar, D.; Goldberg, M. B.; Tittelmeier, K.; Bromberger, B.; Weierganz, M.; Brandis, M.

    2011-06-01

    We have investigated by simulations and experimentally the parameters that affect image quality (contrast and spatial-resolution) of the fast neutron TRION detector. A scintillating fiber screen with 0.5×0.5 mm 2 square fibers, few centimeters thick, provides superior spatial-resolution to that of a slab scintillator of the same thickness. A detailed calculation of the neutron interaction processes that influence the point-spread function (PSF) in the scintillating screen has been performed using the GEANT 3.21 code. The calculations showed that neutron scattering within the screen accounts for a significant loss of image contrast. The factors that limit the spatial-resolution of the image are the cross-sectional scintillating-fiber dimensions within the screen and the spatial response of the image-intensifier. A deconvolution method has been applied for restoring the contrast and the spatial-resolution of the fast neutron image.

  17. DIANE stationary neutron radiography system image quality and industrial applications

    NASA Astrophysics Data System (ADS)

    Cluzeau, S.; Huet, J.; Le Tourneur, P.

    1994-05-01

    The SODERN neutron radiography laboratory has operated since February 1993 using a sealed tube generator (GENIE 46). An experimental programme of characterization (dosimetry, spectroscopy) has confirmed the expected performances concerning: neutron flux intensity, neutron energy range, residual gamma flux. Results are given in a specific report [2]. This paper is devoted to the image performance reporting. ASTM and specific indicators have been used to test the image quality with various converters and films. The corresponding modulation transfer functions are to be determined from image processing. Some industrial applications have demonstrated the capabilities of the system: corrosion detection in aircraft parts, ammunitions filling testing, detection of polymer lacks in sandwich steel sheets, detection of moisture in a probe for geophysics, residual ceramic cores imaging in turbine blades. Various computerized electronic imaging systems will be tested to improve the industrial capabilities.

  18. Field calibration of PADC track etch detectors for local neutron dosimetry in man using different radiation qualities

    NASA Astrophysics Data System (ADS)

    Hälg, Roger A.; Besserer, Jürgen; Boschung, Markus; Mayer, Sabine; Clasie, Benjamin; Kry, Stephen F.; Schneider, Uwe

    2012-12-01

    In order to quantify the dose from neutrons to a patient for contemporary radiation treatment techniques, measurements inside phantoms, representing the patient, are necessary. Published reports on neutron dose measurements cover measurements performed free in air or on the surface of phantoms and the doses are expressed in terms of personal dose equivalent or ambient dose equivalent. This study focuses on measurements of local neutron doses inside a radiotherapy phantom and presents a field calibration procedure for PADC track etch detectors. An initial absolute calibration factor in terms of Hp(10) for personal dosimetry is converted into neutron dose equivalent and additional calibration factors are derived to account for the spectral changes in the neutron fluence for different radiation therapy beam qualities and depths in the phantom. The neutron spectra used for the calculation of the calibration factors are determined in different depths by Monte Carlo simulations for the investigated radiation qualities. These spectra are used together with the energy dependent response function of the PADC detectors to account for the spectral changes in the neutron fluence. The resulting total calibration factors are 0.76 for a photon beam (in- and out-of-field), 1.00 (in-field) and 0.84 (out-of-field) for an active proton beam and 1.05 (in-field) and 0.91 (out-of-field) for a passive proton beam, respectively. The uncertainty for neutron dose measurements using this field calibration method is less than 40%. The extended calibration procedure presented in this work showed that it is possible to use PADC track etch detectors for measurements of local neutron dose equivalent inside anthropomorphic phantoms by accounting for spectral changes in the neutron fluence.

  19. Experimental setup for the determination of the correction factors of the neutron doseratemeters in fast neutron fields

    SciTech Connect

    Iliescu, Elena; Bercea, Sorin; Dudu, Dorin; Celarel, Aurelia

    2013-12-16

    The use of the U-120 Cyclotron of the IFIN-HH allowed to perform a testing bench with fast neutrons in order to determine the correction factors of the doseratemeters dedicated to neutron measurement. This paper deals with researchers performed in order to develop the irradiation facility testing the fast neutrons flux generated at the Cyclotron. This facility is presented, together with the results obtain in determining the correction factor for a doseratemeter dedicated to the neutron dose equivalent rate measurement.

  20. Quality factors in interventional neuroradiology.

    PubMed

    Lasjaunias, P

    2001-01-01

    The interest we take in medical economics and strategy is like the one we take in politics: we may scorn politics, but it cannot be denied that it commands our entire life. For this reason, we must try to determine the conditions required to evaluate the quality of interventional neuroradiology, its operators, its practice, its advances, its teaching, and to maintain this quality. It is probably vital to the freedom of our future therapeutic decisions that we contribute effectively to this discussion before the standard is forced upon us by an exclusively economical or administrative logic. On the other hand, any advance can only be turned into progress if it is diffused and applied. There is no doubt that several levels of quality are acceptable, thus the best approach will be to look for and identify the minimum standard for quality or the limits of non-quality. We shall refrain from suggesting that the level of excellence at a given moment should be imposed upon all operators and constitute the standard level of practice. Practice is based on knowledge and competence. The most skilled surgical act cannot guarantee safe medical treatment if it is not supported by sufficient knowledge about the diseases and their symptoms. Mastership of the decision process requires a thorough vision of the therapeutic decision tree involved. Quality is a composition of global view and detailed analysis to allow a fuzzy gestion of the performance. Regardless of the plan chosen, openmindedness should be kept to allow adaptation, correction or interruption of a given therapeutic process in view of unpredicted pieces of information. Such input is a predictable possibility that should be explained to the patient prior to starting the procedure. Dealing with human beings, the attitude along with the technical management will be of paramount importance in the overall quality assessment. PMID:11840701

  1. Neutron and Gamma-Ray Kerma Factors Based on LLNL Nuclear Data Files.

    Energy Science and Technology Software Center (ESTSC)

    1991-07-08

    Version 00 Kerma factors are used extensively in biomedical applications. Specifically, neutron kerma factors are used in determining heating in materials of interest from neutron-induced reactions in fission or fusion power applications.

  2. Neutron Spectroscopic factors of 56Ni

    NASA Astrophysics Data System (ADS)

    Sanetullaev, A.; Ghosh, T. K.; Lynch, W. G.; Bazin, D.; Chajecki, Z.; Coupland, Daniel; Hodges, R.; Lee, Jenny; Henzl, V.; Henzlova, D.; Rogers, A. M.; Sun, Z. Y.; Tsang, M. B.; Winkelbauer, J.; Youngs, M.; Famiano, M.; Clement, R. R. C.; Howard, M. E.; Cizewski, J. A.; O'Malley, P. D.; Manning, B.; Charity, R. J.; Charity, L. G.; Shapira, D.; Shmitt, K. T.

    2011-10-01

    The exact shell-structure of the unstable doubly-magic nucleus 56Ni has attracted a lot of interest recently. To test if 56Ni is a good core, 56Ni(p, d)55Ni transfer reactions were measured using 56Ni beam at two different energies, 37 MeV/u and 80 MeV/u, in inverse kinematics in two experiments. The second measurement was done in order to test the sensitivity of reaction cross sections and models to reaction energies. The measurements were performed at NSCL using HiRA array and S800 spectrometer. Spectroscopic factors have been extracted for the first experiment. The results show good agreement with shell-model calculations. Preliminary results of the measurements with 80 MeV/u beam will be presented as well. This work is funded by NSF under Grant No. PHY-0606007.

  3. Performance of non-conventional factorization approaches for neutron kinetics

    SciTech Connect

    Bulla, S.; Nervo, M.

    2013-07-01

    The use of factorization techniques provides a interesting option for the simulation of the time-dependent behavior of nuclear systems with a reduced computational effort. While point kinetics neglects all spatial and spectral effects, quasi-statics and multipoint kinetics allow to produce results with a higher accuracy for transients involving relevant modifications of the neutron distribution. However, in some conditions these methods can not work efficiently. In this paper, we discuss some possible alternative formulations for the factorization process for neutron kinetics, leading to mathematical models of reduced complications that can allow an accurate simulation of transients involving spatial and spectral effects. The performance of these innovative approaches are compared to standard techniques for some test cases, showing the benefits and shortcomings of the method proposed. (authors)

  4. Neutron kerma factors and water equivalence of some tissue substitutes.

    PubMed

    Singh, V P; Badiger, N M; Vega-Carrillo, Hector Rene

    2015-09-01

    The Kerma factors and Kerma relative to the air and water of 24 compounds that are used as tissue substitutes were calculated for neutron energies ranging from 2.53×10(-8) to 29 MeV. The Kerma ratios of the tissue substitutes relative to air and water were calculated. The water equivalence of the selected tissue substitutes was observed above neutron energies of 100 eV. The Kerma ratio relative to the air for poly-vinylidene fluoride and Teflon were nearest to unity at very low energy (up to 1 eV) and above 63 eV, respectively. It was found that the natural rubber was a water-equivalent tissue substitute compound. The results of the Kerma factors in our investigation show good agreement with those published in ICRU-44. We found that at higher neutron energies, the Kerma factors and Kerma ratios of the selected tissue substitute compounds were approximately the same, but though the differences were large for energies below 100 eV. PMID:26073270

  5. Factors Affecting the Quality of Staff Development.

    ERIC Educational Resources Information Center

    Purcell, Larry O.

    A review of the literature concerning the effectiveness and quality of staff development programs focuses on factors that affect the success of such programs. These factors include: individual concerns, training activities, applications, qualifications of consultants, scheduling, strategies, facilities, feedback, collaboration, and outcomes. It is…

  6. Nonmotion factors which can affect ride quality

    NASA Technical Reports Server (NTRS)

    Conner, D. W.

    1975-01-01

    Data pertaining to nonmotion factors affecting ride quality of transport aircraft were obtained as part of NASA in-house and sponsored research studies carried out onboard commuter-airline and research aircraft. From these data, quantitative effects on passenger discomfort of seat width, seat legroom, change in cabin pressure, and cabin noise are presented. Visual cue effects are also discussed.

  7. Factors Affecting School Quality in Florida

    ERIC Educational Resources Information Center

    Thornton, Barry; Arbogast, Gordon

    2014-01-01

    This paper examines the factors that are theorized to be determinants of school quality in the 67 counties of Florida from 2000 to 2011. The model constructed for this purpose is comprised of a mix of independent variables that include county educational attainment (number of high school graduates and State University System enrollees) and…

  8. Factors that Predict Quality Classroom Technology Use

    ERIC Educational Resources Information Center

    Hastings, Tricia A.

    2009-01-01

    Despite technological advancements intended to enhance teaching and learning in the 21st century, numerous teacher and school factors continue to impede quality classroom technology use. Determining the effectiveness of educational technology is challenging and requires a detailed understanding of multifaceted, complex, contextual relationships.…

  9. Factors affecting water quality in Cherokee Reservoir

    SciTech Connect

    Iwanski, M.L.; Higgins, J.M.; Kim, B.R.; Young, R.C.

    1980-07-01

    The purpose was to: (1) define reservoir problems related to water quality conditions; (2) identify the probable causes of these problems; and (3) recommend procedures for achieving needed reservoir water quality improvements. This report presents the project findings to date and suggests steps for upgrading the quality of Cherokee Reservoir. Section II presents background information on the characteristics of the basin, the reservoir, and the beneficial uses of the reservoir. Section III identifies the impacts of existing reservoir water quality on uses of the reservoir for water supply, fishery resources, recreation, and waste assimilation. Section IV presents an assessment of cause-effect relationships. The factors affecting water quality addressed in Section IV are: (1) reservoir thermal stratification and hydrodynamics; (2) dissolved oxygen depletion; (3) eutrophication; (4) toxic substances; and (5) reservoir fisheries. Section V presents a preliminary evaluation of alternatives for improving the quality of Cherokee Reservoir. Section VI presents preliminary conclusions and recommendations for developing and implementing a reservoir water quality management plan. 7 references, 22 figures, 21 tables.

  10. High quality factor indium oxide mechanical microresonators

    SciTech Connect

    Bartolomé, Javier Cremades, Ana; Piqueras, Javier

    2015-11-09

    The mechanical resonance behavior of as-grown In{sub 2}O{sub 3} microrods has been studied in this work by in-situ scanning electron microscopy (SEM) electrically induced mechanical oscillations. Indium oxide microrods grown by a vapor–solid method are naturally clamped to an aluminum oxide ceramic substrate, showing a high quality factor due to reduced energy losses during mechanical vibrations. Quality factors of more than 10{sup 5} and minimum detectable forces of the order of 10{sup −16} N/Hz{sup 1/2} demonstrate their potential as mechanical microresonators for real applications. Measurements at low-vacuum using the SEM environmental operation mode were performed to study the effect of extrinsic damping on the resonators behavior. The damping coefficient has been determined as a function of pressure.

  11. The Neutron Magnetic Form Factor at High Q{sup 2}: Experimental Status, Future Measurements

    SciTech Connect

    Will Brooks

    2002-05-01

    Recent progress in improving our knowledge of the four nucleon form factors G{sup p}{sub M}, G{sup p}{sub E}, G{sup n}{sub M}, G{sup n}{sub E} at high momentum transfer is stimulating a new wave of theoretical efforts to describe these fundamental quantities. Both model calculations and lattice QCD can predict the elastic form factors; a definitive, stringent test of these efforts is to predict all of them simultaneously. However, the limited range and quality of the data for the neutron magnetic form factor G{sup n}{sub M} presently reduce the discriminating power of such a test. The present status of our knowledge of G{sup n}{sub M} is discussed, and prospects for future improvements are presented.

  12. [Factors that affect inpatients' quality of sleep].

    PubMed

    da Costa, Shíntia Viana; Ceolim, Maria Filomena

    2013-02-01

    The aim of this study was to identify factors that interfere with the sleep quality of patients admitted to a university hospital in a city in the state of São Paulo, Brazil. This was an exploratory, cross sectional study using non-probability sampling. Participants were 117 patients (59% men, mean age 48.0 years, standard deviation 16.9) hospitalized for at least 72 hours in stable clinical condition. The data were collected with an identification questionnaire and the Factors Affecting Sleep Quality (FASQ) questionnaire. Data processing was performed with descriptive statistics; each item of the FASQ underwent a test and a retest. The factors most often reported were waking up early (55.6%), disrupted sleep (52.1%), excessive lighting (34.2%), receipt of care by nursing staff (33.3%) and organic disorders such as pain and fatigue (26.5%). It is suggested that nurses should plan interventions to modify factors that require intense noise and lighting at night in order to reduce disruption and, consequently, sleep deprivation among patients. PMID:23515802

  13. 7 CFR 52.810 - Allowances for quality factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Allowances for quality factors. 52.810 Section 52.810 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... for Quality Factors § 52.810 Allowances for quality factors. Table I—Allowances for Quality...

  14. 7 CFR 52.782 - Allowances for quality factors.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Allowances for quality factors. 52.782 Section 52.782 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... for Quality Factors § 52.782 Allowances for quality factors. Table IV—Allowances for Quality...

  15. Neutron-Proton Asymmetry Dependence of Spectroscopic Factors in Ar Isotopes

    SciTech Connect

    Lee, Jenny; Tsang, Betty; Shapira, Dan

    2010-01-01

    Spectroscopic factors have been extracted for proton-rich 34Ar and neutron-rich 46Ar using the (p, d) neutron transfer reaction. The experimental results show little reduction of the ground state neutron spectroscopic factor of the proton-rich nucleus 34Ar compared to that of 46Ar. The results suggest that correlations, which generally reduce such spectroscopic factors, do not depend strongly on the neutron-proton asymmetry of the nucleus in this isotopic region as was reported in knockout reactions. The present results are consistent with results from systematic studies of transfer reactions but inconsistent with the trends observed in knockout reaction measurements.

  16. Neutron-Proton Asymmetry Dependence of Spectroscopic Factors in Ar Isotopes

    NASA Astrophysics Data System (ADS)

    Lee, Jenny; Tsang, M. B.; Bazin, D.; Coupland, D.; Henzl, V.; Henzlova, D.; Kilburn, M.; Lynch, W. G.; Rogers, A. M.; Sanetullaev, A.; Signoracci, A.; Sun, Z. Y.; Youngs, M.; Chae, K. Y.; Charity, R. J.; Cheung, H. K.; Famiano, M.; Hudan, S.; O'Malley, P.; Peters, W. A.; Schmitt, K.; Shapira, D.; Sobotka, L. G.

    2010-03-01

    Spectroscopic factors have been extracted for proton-rich Ar34 and neutron-rich Ar46 using the (p, d) neutron transfer reaction. The experimental results show little reduction of the ground state neutron spectroscopic factor of the proton-rich nucleus Ar34 compared to that of Ar46. The results suggest that correlations, which generally reduce such spectroscopic factors, do not depend strongly on the neutron-proton asymmetry of the nucleus in this isotopic region as was reported in knockout reactions. The present results are consistent with results from systematic studies of transfer reactions but inconsistent with the trends observed in knockout reaction measurements.

  17. Vocal quality factors: analysis, synthesis, and perception.

    PubMed

    Childers, D G; Lee, C K

    1991-11-01

    The purpose of this study was to examine several factors of vocal quality that might be affected by changes in vocal fold vibratory patterns. Four voice types were examined: modal, vocal fry, falsetto, and breathy. Three categories of analysis techniques were developed to extract source-related features from speech and electroglottographic (EGG) signals. Four factors were found to be important for characterizing the glottal excitations for the four voice types: the glottal pulse width, the glottal pulse skewness, the abruptness of glottal closure, and the turbulent noise component. The significance of these factors for voice synthesis was studied and a new voice source model that accounted for certain physiological aspects of vocal fold motion was developed and tested using speech synthesis. Perceptual listening tests were conducted to evaluate the auditory effects of the source model parameters upon synthesized speech. The effects of the spectral slope of the source excitation, the shape of the glottal excitation pulse, and the characteristics of the turbulent noise source were considered. Applications for these research results include synthesis of natural sounding speech, synthesis and modeling of vocal disorders, and the development of speaker independent (or adaptive) speech recognition systems. PMID:1837797

  18. Nodal weighting factor method for ex-core fast neutron fluence evaluation

    SciTech Connect

    Chiang, R. T.

    2012-07-01

    The nodal weighting factor method is developed for evaluating ex-core fast neutron flux in a nuclear reactor by utilizing adjoint neutron flux, a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV, the unit fission source, and relative assembly nodal powers. The method determines each nodal weighting factor for ex-core neutron fast flux evaluation by solving the steady-state adjoint neutron transport equation with a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV as the adjoint source, by integrating the unit fission source with a typical fission spectrum to the solved adjoint flux over all energies, all angles and given nodal volume, and by dividing it with the sum of all nodal weighting factors, which is a normalization factor. Then, the fast neutron flux can be obtained by summing the various relative nodal powers times the corresponding nodal weighting factors of the adjacent significantly contributed peripheral assembly nodes and times a proper fast neutron attenuation coefficient over an operating period. A generic set of nodal weighting factors can be used to evaluate neutron fluence at the same location for similar core design and fuel cycles, but the set of nodal weighting factors needs to be re-calibrated for a transition-fuel-cycle. This newly developed nodal weighting factor method should be a useful and simplified tool for evaluating fast neutron fluence at selected locations of interest in ex-core components of contemporary nuclear power reactors. (authors)

  19. Improvements in the Image Quality of Neutron Radiograms of NUR Neutron Radiography Facility by Using Several Exposure Techniques

    NASA Astrophysics Data System (ADS)

    Zergoug, T.; Nedjar, A.; Mokeddem, M. Y.; Mammou, L.

    2008-03-01

    Since the construction of NUR reactor neutron radiography facility in 1991, only transfer exposure method was used as a non destructive technique. The reason is the excess of gamma rays in the neutron beam. To improve radiation performances of the NR system, a stainless steal hollow conical cylinder is introduced at the bottom of the facility beam port, this filter reduce gamma infiltration through the edges of the NR structure without disturbing neutron beam arriving from the in pool divergent collimator. First results confirm our prediction; a gamma rays diminution and a relatively stable neutron flux at the point object are confirmed, consequently the n/γ ratio reaches a value of 2.104 n/cm2 mR. Radiograms obtained by using the direct exposure method reveal the feasibility of the technique in the new NR configuration facility, but a weak resolution and contrast of the image is observed. In this paper, we describe a procedure to improve the image quality obtained by direct exposure technique. The process consists of using digitized images obtained by several exposure techniques (NR, gamma radiography or X radiography) for a comparison study and then better image definition can be attained.

  20. Improvements in the Image Quality of Neutron Radiograms of NUR Neutron Radiography Facility by Using Several Exposure Techniques

    SciTech Connect

    Zergoug, T.; Nedjar, A.; Mokeddem, M. Y.; Mammou, L.

    2008-03-17

    Since the construction of NUR reactor neutron radiography facility in 1991, only transfer exposure method was used as a non destructive technique. The reason is the excess of gamma rays in the neutron beam. To improve radiation performances of the NR system, a stainless steal hollow conical cylinder is introduced at the bottom of the facility beam port, this filter reduce gamma infiltration through the edges of the NR structure without disturbing neutron beam arriving from the in pool divergent collimator. First results confirm our prediction; a gamma rays diminution and a relatively stable neutron flux at the point object are confirmed, consequently the n/{gamma} ratio reaches a value of 2.104 n/cm{sup 2} mR. Radiograms obtained by using the direct exposure method reveal the feasibility of the technique in the new NR configuration facility, but a weak resolution and contrast of the image is observed. In this paper, we describe a procedure to improve the image quality obtained by direct exposure technique. The process consists of using digitized images obtained by several exposure techniques (NR, gamma radiography or X radiography) for a comparison study and then better image definition can be attained.

  1. Biophysics of NASA radiation quality factors.

    PubMed

    Cucinotta, Francis A

    2015-09-01

    NASA has implemented new radiation quality factors (QFs) for projecting cancer risks from space radiation exposures to astronauts. The NASA QFs are based on particle track structure concepts with parameters derived from available radiobiology data, and NASA introduces distinct QFs for solid cancer and leukaemia risk estimates. The NASA model was reviewed by the US National Research Council and approved for use by NASA for risk assessment for International Space Station missions and trade studies of future exploration missions to Mars and other destinations. A key feature of the NASA QFs is to represent the uncertainty in the QF assessments and evaluate the importance of the QF uncertainty to overall uncertainties in cancer risk projections. In this article, the biophysical basis for the probability distribution functions representing QF uncertainties was reviewed, and approaches needed to reduce uncertainties were discussed. PMID:25883309

  2. The neutron electric form factor to Q² = 1.45 (GeV/c)²

    SciTech Connect

    Bradley Plaster

    2004-02-01

    The nucleon elastic electromagnetic form factors are fundamental quantities needed for an understanding of nucleon and nuclear electromagnetic structure. The evolution of the Sachs electric and magnetic form factors with Q2, the square of the four-momentum transfer, is related to the distribution of charge and magnetization within the nucleon. High precision measurements of the nucleon form factors are essential for stringent tests of our current theoretical understanding of confinement within the nucleon. Measurements of the neutron form factors, in particular, those of the neutron electric form factor, have been notoriously difficult due to the lack of a free neutron target and the vanishing integral charge of the neutron. Indeed, a precise measurement of the neutron electric form factor has eluded experimentalists for decades; however, with the advent of high duty-factor polarized electron beam facilities, experiments employing polarization degrees of freedom have finally yielded the first precise measurements of this fundamental quantity. Following a general overview of the experimental and theoretical status of the nucleon form factors, a detailed description of an experiment designed to extract the neutron electric form factor from measurements of the neutron's recoil polarization in quasielastic 2H(e, e')1H scattering is presented. The experiment described here employed the Thomas Jefferson National Accelerator Facility's longitudinally polarized electron beam, a magnetic spectrometer for detection of the scattered electron, and a neutron polarimeter designed specifically for this experiment. Measurements were conducted at three Q2 values of 0.45, 1.13, and 1.45 (GeV/c)2, and the final results extracted from an analysis of the data acquired in this experiment are reported and compared with recent theoretical predictions for the nucleon form factors.

  3. Comment on ``Spectroscopic factors for bound s-wave states derived from neutron scattering lengths''

    NASA Astrophysics Data System (ADS)

    Barker, F. C.

    1997-12-01

    The procedure proposed by Mohr et al. [Phys. Rev. C 55, 1591 (1997)] for extracting the spectroscopic factor for a bound s-wave neutron state from the scattering length appears to be of doubtful validity and accuracy.

  4. Quality factors for alpha particles emitted in tissue

    NASA Technical Reports Server (NTRS)

    Borak, Thomas B.; Chatterjee, A. (Principal Investigator)

    2002-01-01

    A concept of a mean or dose averaged quality factor was defined in ICRP Publication 26 using relationships for quality factor as a function of LET. The concept of radiation weighting factors, wR, was introduced in ICRP Publication 60 in 1990. These are meant to be generalized factors that modify absorbed dose to reflect the risk of stochastic effects as a function of the quality of the radiation incident on the body or emitted by radioactivity within the body. The values of wr are equal to 20 for all alpha particles externally or internally emitted. This note compares the dose averaged quality factor for alpha particles originating in tissue using the old and revised recommendations for quality factor as a function of LET. The dose averaged quality factor never exceeds 20 using the old recommendations and is never less than 20 with the revised recommendations.

  5. Personnel neutron dosimetry

    SciTech Connect

    Hankins, D.

    1982-04-01

    This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs. (ACR)

  6. Calculation of self-shielding factor for neutron activation experiments using GEANT4 and MCNP

    NASA Astrophysics Data System (ADS)

    Romero-Barrientos, Jaime; Molina, F.; Aguilera, Pablo; Arellano, H. F.

    2016-07-01

    The neutron self-shielding factor G as a function of the neutron energy was obtained for 14 pure metallic samples in 1000 isolethargic energy bins from 1.10-5eV to 2.107eV using Monte Carlo simulations in GEANT4 and MCNP6. The comparison of these two Monte Carlo codes shows small differences in the final self-shielding factor mostly due to the different cross section databases that each program uses.

  7. Interpreting the neutron's electric form factor: Rest frame charge distribution or foldy term?

    SciTech Connect

    Nathan Isgur

    1998-12-01

    The neutron's electric form factor contains vital information on nucleon structure, but its interpretation within many models has been obscured by relativistic effects. The author demonstrates that, to leading order in the relativistic expansion of a constituent quark model, the Foldy term cancels exactly against a contribution to the Dirac form factor F{sub 1} to leave intact the naive interpretation of G{sup n}{sub E} as arising from the neutron's rest frame charge distribution.

  8. Neutron dose per fluence and weighting factors for use at high energy accelerators

    SciTech Connect

    Cossairt, J.Donald; Vaziri, Kamran; /Fermilab

    2008-07-01

    In June 2007, the United States Department of Energy incorporated revised values of neutron weighting factors into its occupational radiation protection Regulation 10 CFR Part 835 as part of updating its radiation dosimetry system. This has led to a reassessment of neutron radiation fields at high energy proton accelerators such as those at the Fermi National Accelerator Laboratory (Fermilab). Values of dose per fluence factors appropriate for accelerator radiation fields calculated elsewhere are collated and radiation weighting factors compared. The results of this revision to the dosimetric system are applied to americium-beryllium neutron energy spectra commonly used for instrument calibrations. A set of typical accelerator neutron energy spectra previously measured at Fermilab are reassessed in light of the new dosimetry system. The implications of this revision are found to be of moderate significance.

  9. Calculated neutron KERMA factors based on the LLNL ENDL data file. Volume 27

    SciTech Connect

    Howerton, R.J.

    1986-01-01

    Neutron KERMA factors calculated from the LLNL ENDL data file are tabulated for 15 composite materials and for the isotopes or elements in the ENDL file from Z = 1 to Z = 29. The incident neutron energies range from 1.882 x 10/sup -5/ to 20. MeV for the composite materials and from 1.30 x 10/sup -9/ to 20. MeV for the isotopes and elements.

  10. Factors affecting enhanced video quality preferences

    PubMed Central

    Satgunam, PremNandhini; Woods, Russell L; Bronstad, P Matthew; Peli, Eli

    2013-01-01

    The development of video quality metrics requires methods for measuring perceived video quality. Most such metrics are designed and tested using databases of images degraded by compression and scored using opinion ratings. We studied video quality preferences for enhanced images of normally-sighted participants using the method of paired comparisons with a thorough statistical analysis. Participants (n=40) made pair-wise comparisons of high definition (HD) video clips enhanced at four different levels using a commercially available enhancement device. Perceptual scales were computed with binary logistic regression to estimate preferences for each level and to provide statistical inference of the differences among levels and the impact of other variables. While moderate preference for enhanced videos was found, two unexpected effects were also uncovered: (1) Participants could be broadly classified into two groups: those who preferred enhancement ("Sharp") and those who disliked enhancement ("Smooth"). (2) Enhancement preferences depended on video content, particularly for human faces to be enhanced less. The results suggest that algorithms to evaluate image quality (at least for enhancement) may need to be adjusted or applied differentially based on video content and viewer preferences. The possible impact of similar effects on image quality of compressed video needs to be evaluated. PMID:24107400

  11. Factors Associated With Sleep Quality Among Operating Engineers

    PubMed Central

    Choi, Seung Hee; Terrell, Jeffrey E.; Pohl, Joanne M.; Redman, Richard W.

    2016-01-01

    Blue collar workers generally report high job stress and are exposed to loud noises at work and engage in many of the health behavioral factors, all of which have been associated with poor sleep quality. However, sleep quality of blue collar workers has not been studied extensively, and no studies have focused Operating Engineers (heavy equipment operators) among whom daytime fatigue would place them at high risk for accidents. Therefore, the purpose of this study was to determine variables associated with sleep quality among Operating Engineers. This was a cross-sectional survey design with a dependent variable of sleep quality and independent variables of personal and related health behavioral factors. A convenience sample of 498 Operating Engineers was recruited from approximately 16,000 Operating Engineers from entire State of Michigan in 2008. Linear regression was used to determine personal and related health behavior factors associated with sleep quality. Multivariate analyses showed that personal factors related to poor sleep quality were younger age, female sex, higher pain, more medical comorbidities and depressive symptoms and behavioral factors related to poor sleep quality were nicotine dependence. While sleep scores were similar to population norms, approximately 34% (n=143) showed interest in health services for sleep problems. While many personal factors are not changeable, interventions to improve sleep hygiene as well as interventions to treat pain, depression and smoking may improve sleep quality resulting in less absenteeism, fatal work accidents, use of sick leave, work disability, medical comorbidities, as well as subsequent mortality. PMID:23393021

  12. Neutron spectroscopic factors of Ar34 and Ar46 from (p,d) transfer reactions

    NASA Astrophysics Data System (ADS)

    Lee, Jenny; Tsang, M. B.; Bazin, D.; Coupland, D.; Henzl, V.; Henzlova, D.; Kilburn, M.; Lynch, W. G.; Rogers, A. M.; Sanetullaev, A.; Sun, Z. Y.; Youngs, M.; Charity, R. J.; Sobotka, L. G.; Famiano, M.; Hudan, S.; Shapira, D.; O'Malley, P.; Peters, W. A.; Chae, K. Y.; Schmitt, K.

    2011-01-01

    Single-neutron-transfer measurements using (p,d) reactions have been performed at 33 MeV per nucleon with proton-rich Ar34 and neutron-rich Ar46 beams in inverse kinematics. The extracted spectroscopic factors are compared to the large-basis shell-model calculations. Relatively weak quenching of the spectroscopic factors is observed between Ar34 and Ar46. The experimental results suggest that neutron correlations have a weak dependence on the asymmetry of the nucleus over this isotopic region. The present results are consistent with the systematics established from extensive studies of spectroscopic factors and dispersive optical-model analyses of Ca40-49 isotopes. They are, however, inconsistent with the trends obtained in knockout-reaction measurements.

  13. Reduced neutron spectroscopic factors when using potential geometries constrained by Hartree-Fock calculations

    SciTech Connect

    Lee, Jenny; Brown, B.A.; Delaunay, F.; Lynch, W.G.; Saelim, M. J.; Tsang, M.B.; Tostevin, J.A.

    2006-04-15

    We carry out a systematic analysis of angular distribution measurements for selected ground-state to ground-state (d,p) and (p,d) neutron transfer reactions, including the calcium isotopes. We propose a consistent three-body model reaction methodology in which we constrain the transferred-neutron bound state and nucleon-target optical potential geometries using modern Hartree-Fock calculations. Our deduced neutron spectroscopic factors are found to be suppressed by {approx}30% relative to independent-particle shell-model values, from {sup 40}Ca through {sup 49}Ca. The other nuclei studied, ranging from B to Ti, show similar average suppressions with respect to large-basis shell-model expectations. Our results are consistent with deduced spectroscopic strengths for neutrons and protons from intermediate-energy nucleon knockout reactions and for protons from (e,e{sup '}p) reactions on well-bound nuclei.

  14. Exploring Sleep Quality and Related Factors in Chinese Midlife Women.

    PubMed

    Xu, Qunyan; Zhao, Yue; Chen, Hui; Jing, Jianling

    2016-06-01

    We investigated the percentage of women with poor sleep quality and its related factors among mainland Chinese women. Sleep quality and menopausal status were self-reported. We explored the contribution of possible risk factors, including sociodemographic characteristics, comorbidities, lifestyle, psychological status, stressful life events, and vasomotor symptoms. We found that 38.6% of midlife Chinese women were poor sleepers. This percentage was higher in comparison with women from other Asian countries. Our multiple logistic regression showed that anxiety, comorbidities, perceived stress, and vasomotor symptoms were risk factors for poor sleep quality. PMID:25868869

  15. Microscopic structure factor of liquid hydrogen by neutron-diffraction measurements

    NASA Astrophysics Data System (ADS)

    Celli, M.; Bafile, U.; Cuello, G. J.; Formisano, F.; Guarini, E.; Magli, R.; Neumann, M.; Zoppi, M.

    2005-01-01

    The center-of-mass structure factor of liquid para hydrogen has been measured, using neutron diffraction, in four thermodynamic states close to the triple point. Path integral Monte Carlo simulations have been carried out at the same temperatures and densities. The present experimental data are in reasonable quantitative agreement with the simulations and closer to these results than previous neutron determinations available in the literature. The thermodynamic derivatives of the structure factor, from both experiment and simulation, have been compared to previous measurements obtaining a quantitative consistency.

  16. Microdosimetric measurements of radiation quality variations in homogeneous phantoms irradiated by fast neutron beams

    SciTech Connect

    Beach, J.L.; Milavickas, L.R.

    1982-01-01

    The Dual Radiation Action Theory of Kellerer and Rossi (DRA), along with presently available microdosimetric techniques, is applied to the detrmination of radiation quality variation within tissue equivalent phantoms irradiated by collimated fast neutron beams. The neutron beams investigated were produced by the bombardment of 22.5 and 16 MeV d+ on beryllium and by the T(d,n)/sup 4/He reaction (15-MeV neutrons). Microdosimetric spectra were obtained at points of varying depth and lateral distance from the central axis within a tissue equivalent phantom, including points within the penumbra. From the microdosimetric spectra the parameter RQ, a first approximation to RBE derived from DRA theory, is calculated for each point. All RQ values are calculated for the same level of effect. For these three different beams the results show that the RQ values for the total radiation spectrum of neutron and gamma radiation remain fairly constant with depth and with lateral distance from the beam axis at 2 and 10 cm depths. The largest central axis variation in RQ is 8% for the d(16)+Be beam. The largest variation between a penumbra and an on-axis RQ value is 4% at 2 cm depth in the d(22.5)+Be beam. The results for the d(22.5)+Be beam disagree with previously reported radiobiological results while the 15 MeV beam results are in good agreement.

  17. Training, Quality Assurance Factors, and Tools Investigation: a Work Report and Suggestions on Software Quality Assurance

    NASA Technical Reports Server (NTRS)

    Lee, Pen-Nan

    1991-01-01

    Previously, several research tasks have been conducted, some observations were obtained, and several possible suggestions have been contemplated involving software quality assurance engineering at NASA Johnson. These research tasks are briefly described. Also, a brief discussion is given on the role of software quality assurance in software engineering along with some observations and suggestions. A brief discussion on a training program for software quality assurance engineers is provided. A list of assurance factors as well as quality factors are also included. Finally, a process model which can be used for searching and collecting software quality assurance tools is presented.

  18. Gamete quality in fish: evaluation parameters and determining factors.

    PubMed

    Valdebenito, Iván I; Gallegos, Patricia C; Effer, Brian R

    2015-04-01

    The quality of fish gametes, both male and female, are determined by several factors (age, management, feeding, chemical and physical factors, water quality, etc.) that have an impact on the survivability of embryos, larvae and/or fry in the short or long term. One of the most important factors is gamete ageing, especially for those species that are unable to spawn naturally in hatcheries. The chemical and physical factors in hatcheries and the nutrition that they provide can significantly alter harvest quality, especially from females; as a rule, males are more tolerant of stress conditions produced by inadequate feeding, management and/or poor water conditions. The stress produced on broodstock by inadequate conditions in hatcheries can produce adverse effects on gamete quality, survival rates, and the embryonic eggs after hatching. PMID:24229714

  19. Precision measurement of the neutron magnetic form factor from {sup 3}He(e, e')

    SciTech Connect

    Dipangkar Dutta

    2000-12-12

    A precision measurement of the inclusive quasielastic transverse asymmetry A{sub T'} from {sup 3}He(e, e') was completed recently at Hall A at Jefferson Lab (E95-001). The preliminary results on the neutron magnetic form factor at low Q{sup 2} are presented here.

  20. Approaching Safety through Quality: Factors Influencing College Student Perceptions.

    PubMed

    Ramaswamy, S K; Mosher, G A

    2016-04-01

    Quality management practices have been identified by previous literature as a factor that could potentially reduce the level of safety incidents and hazards in agricultural work environments. The present study used multivariate analysis to examine the effect of independent variables such as quality and safety awareness, work experience, safety and quality management experience, and the perceived importance of safety and quality on the role of quality management practices as a mitigating factor for safety hazards and incidents in agriculture. Variables were measured on a five-point scale using a survey questionnaire. Data were collected from approximately 900 undergraduates enrolled in the College of Agriculture and Life Sciences at a large land grant university in the U.S. The level of student work experience and student perceptions of the importance of quality explained a significant amount of the variance in student views of quality management practices as a mitigating factor for safety hazards and incidents. The findings of this study provide further evidence for using quality management practices as a basis for safety interventions targeted at the agricultural workforce. PMID:27373063

  1. Improving Qubit Quality Factors Through Exotic Materials

    NASA Astrophysics Data System (ADS)

    Norman, Victoria

    In the time since the first qubits were successfully fabricated, the coherence times of superconducting Josephson junction qubits have improved by several orders of magnitude. Yet as the quantum information and computation field moves forward, these coherence times still need further improvement. We are now finding that in some superconducting systems, non-thermal equilibrium quasiparticles are becoming the limiting factor in qubit lifetimes. For SIS superconducting qubits, the T1 and T2* values may be improved by the use of materials with higher superconducting band gap, EG, for which low values may allow for quasiparticles to break up cooper pairs more easily, leading to a shorter lifetime. At this time, Al-Al2Ox3-Al transmons are very well characterized and understood and will therefore serve as an appropriate baseline with which to compare the more exotic junction materials. Using tantalum and niobium, which have Eg values of 3 times and 10 times that of aluminum respectively, we expect the T1 and T2* values to increase significantly for the Al-Al2Ox3-Nb, Al-Al2Ox3-Ta, and Ta-Ta2Ox5-Nb qubits.

  2. Preslaughter factors affecting poultry meat quality chapter 2.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Poultry meat quality is affected by numerous antemortem factors, in particular those occurring during the last 24 hours that the bird is alive. These short term factors influence carcass yield (live shrink), carcass defects (bruising, broken/dislocated bones), carcass microbiological contamination, ...

  3. Precise Determination of the Neutron Magnetic Form Factor to Higher Q{sup 2}

    SciTech Connect

    William K. Brooks; Jeffery D. Lachniet

    2004-10-01

    The neutron elastic magnetic form factor G{sub M}{sup n} has been extracted from quasielastic scattering from deuterium in the CEBAF Large Acceptance Spectrometer, CLAS. The kinematic coverage of the measurement is continuous over a broad range, extending from below 1 GeV{sup 2} to nearly 5 GeV{sup 2} in four-momentum transfer squared. High precision is achieved by employing a ratio technique in which most uncertainties cancel, and by a simultaneous in-situ calibration of the neutron detection efficiency, the largest correction to the data. Preliminary results are shown with statistical errors only.

  4. Efficient prediction of the quality factors of micromechanical resonators

    NASA Astrophysics Data System (ADS)

    Choi, Jinbok; Cho, Maenghyo; Rhim, Jaewook

    2010-01-01

    A high quality factor (Q-factor) is one of the major requirements of high-performance resonators. An understanding of the dissipation mechanism is crucial for maximizing the quality factor by reducing the energy loss. Thermoelastic damping has been well-known as the important intrinsic dissipation that affects the quality factor of micro-resonators. In this study, a finite element formulation based on the weak form of fully coupled thermoelastic problems is suggested. The coupled thermoelastic equation usually leads to a large-size complex eigenvalue problem, which is very massive and time-consuming to solve. Therefore, we also applied the model order reduction (MOR) scheme to this coupled multiphysical problem in order to achieve computational efficiency. The present approach is validated by comparing the numerical results and analytical solutions.

  5. Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy

    NASA Astrophysics Data System (ADS)

    Hälg, R. A.; Besserer, J.; Boschung, M.; Mayer, S.; Lomax, A. J.; Schneider, U.

    2014-05-01

    In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small.

  6. Measurements of the neutron dose equivalent for various radiation qualities, treatment machines and delivery techniques in radiation therapy.

    PubMed

    Hälg, R A; Besserer, J; Boschung, M; Mayer, S; Lomax, A J; Schneider, U

    2014-05-21

    In radiation therapy, high energy photon and proton beams cause the production of secondary neutrons. This leads to an unwanted dose contribution, which can be considerable for tissues outside of the target volume regarding the long term health of cancer patients. Due to the high biological effectiveness of neutrons in regards to cancer induction, small neutron doses can be important. This study quantified the neutron doses for different radiation therapy modalities. Most of the reports in the literature used neutron dose measurements free in air or on the surface of phantoms to estimate the amount of neutron dose to the patient. In this study, dose measurements were performed in terms of neutron dose equivalent inside an anthropomorphic phantom. The neutron dose equivalent was determined using track etch detectors as a function of the distance to the isocenter, as well as for radiation sensitive organs. The dose distributions were compared with respect to treatment techniques (3D-conformal, volumetric modulated arc therapy and intensity-modulated radiation therapy for photons; spot scanning and passive scattering for protons), therapy machines (Varian, Elekta and Siemens linear accelerators) and radiation quality (photons and protons). The neutron dose equivalent varied between 0.002 and 3 mSv per treatment gray over all measurements. Only small differences were found when comparing treatment techniques, but substantial differences were observed between the linear accelerator models. The neutron dose equivalent for proton therapy was higher than for photons in general and in particular for double-scattered protons. The overall neutron dose equivalent measured in this study was an order of magnitude lower than the stray dose of a treatment using 6 MV photons, suggesting that the contribution of the secondary neutron dose equivalent to the integral dose of a radiotherapy patient is small. PMID:24778349

  7. Conversion factors from counts to chemical ratios for the EURITRACK tagged neutron inspection system

    NASA Astrophysics Data System (ADS)

    El Kanawati, W.; Perot, B.; Carasco, C.; Eleon, C.; Valkovic, V.; Sudac, D.; Obhodas, J.

    2011-10-01

    The EURopean Illicit TRAfficking Countermeasures Kit (EURITRACK) uses 14 MeV neutrons produced by the 3H(d,n) 4H fusion reaction to detect explosives and narcotics in cargo containers. Reactions induced by fast neutrons produce gamma rays, which are detected in coincidence with the associated alpha particle to determine the neutron direction. In addition, the neutron path length is obtained from a time-of-flight measurement, thus allowing the origin of the gamma rays inside the container to be determined. Information concerning the chemical composition of the target material is obtained from the analysis of the energy spectrum. The carbon, oxygen, and nitrogen relative count contributions must be converted to chemical proportions to distinguish illicit and benign organic materials. An extensive set of conversion factors based on Monte Carlo numerical simulations has been calculated, taking into account neutron slowing down and photon attenuation in the cargo materials. An experimental validation of the method is presented by comparing the measured chemical fractions of known materials, in the form of bare samples or hidden in a cargo container, to their real chemical composition. Examples of application to real cargo containers are also reported, as well as simulated data with explosives and illicit drugs.

  8. Nanodosimetry-based quality factors for radiation protection in space.

    PubMed

    Schulte, Reinhard W; Wroe, Andrew J; Bashkirov, Vladimir A; Garty, Guy Y; Breskin, Amos; Chechik, Rachel; Shchemelinin, Sergei; Gargioni, Elisabetta; Grosswendt, Bernd; Rosenfeld, Anatoly B

    2008-01-01

    Evaluation and monitoring of the cancer risk from space radiation exposure is a crucial requirement for the success of long-term space missions. One important task in the risk calculation is to properly weigh the various components of space radiation dose according to their assumed contribution to the cancer risk relative to the risk associated with radiation of low ionization density. Currently, quality factors of radiation both on the ground and in space are defined by national and international commissions based on existing radiobiological data and presumed knowledge of the ionization density distribution of the radiation field at a given point of interest. This approach makes the determination of the average quality factor ofa given radiation field a rather complex task. In this contribution, we investigate the possibility to define quality factors of space radiation exposure based on nanodosimetric data. The underlying formalism of the determination of quality factors on the basis of nanodosimetric data is described, and quality factors for protons and ions (helium and carbon) of different energies based on simulated nanodosimetric data are presented. The value and limitations of this approach are discussed. PMID:19205298

  9. Precise Measurement of the Neutron Magnetic Form Factor GMn in the Few-GeV2 Region

    NASA Astrophysics Data System (ADS)

    Lachniet, J.; Afanasev, A.; Arenhövel, H.; Brooks, W. K.; Gilfoyle, G. P.; Higinbotham, D.; Jeschonnek, S.; Quinn, B.; Vineyard, M. F.; Adams, G.; Adhikari, K. P.; Amaryan, M. J.; Anghinolfi, M.; Asavapibhop, B.; Asryan, G.; Avakian, H.; Bagdasaryan, H.; Baillie, N.; Ball, J. P.; Baltzell, N. A.; Barrow, S.; Batourine, V.; Battaglieri, M.; Beard, K.; Bedlinskiy, I.; Bektasoglu, M.; Bellis, M.; Benmouna, N.; Berman, B. L.; Biselli, A. S.; Bonner, B. E.; Bookwalter, C.; Bouchigny, S.; Boiarinov, S.; Bradford, R.; Branford, D.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Calarco, J. R.; Careccia, S. L.; Carman, D. S.; Casey, L.; Cheng, L.; Cole, P. L.; Coleman, A.; Collins, P.; Cords, D.; Corvisiero, P.; Crabb, D.; Crede, V.; Cummings, J. P.; Dale, D.; Daniel, A.; Dashyan, N.; de Masi, R.; de Vita, R.; de Sanctis, E.; Degtyarenko, P. V.; Denizli, H.; Dennis, L.; Deur, A.; Dhamija, S.; Dharmawardane, K. V.; Dhuga, K. S.; Dickson, R.; Djalali, C.; Dodge, G. E.; Doughty, D.; Dragovitsch, P.; Dugger, M.; Dytman, S.; Dzyubak, O. P.; Egiyan, H.; Egiyan, K. S.; El Fassi, L.; Elouadrhiri, L.; Empl, A.; Eugenio, P.; Fatemi, R.; Fedotov, G.; Fersch, R.; Feuerbach, R. J.; Forest, T. A.; Fradi, A.; Gabrielyan, M. Y.; Garçon, M.; Gavalian, G.; Gevorgyan, N.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Graham, L.; Griffioen, K. A.; Guidal, M.; Guillo, M.; Guler, N.; Guo, L.; Gyurjyan, V.; Hadjidakis, C.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Hardie, J.; Hassall, N.; Heddle, D.; Hersman, F. W.; Hicks, K.; Hleiqawi, I.; Holtrop, M.; Hu, J.; Huertas, M.; Hyde-Wright, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Ito, M. M.; Jenkins, D.; Jo, H. S.; Johnstone, J. R.; Joo, K.; Juengst, H. G.; Kageya, T.; Kalantarians, N.; Keller, D.; Kellie, J. D.; Khandaker, M.; Khetarpal, P.; Kim, K. Y.; Kim, K.; Kim, W.; Klein, A.; Klein, F. J.; Klusman, M.; Konczykowski, P.; Kossov, M.; Kramer, L. H.; Kubarovsky, V.; Kuhn, J.; Kuhn, S. E.; Kuleshov, S. V.; Kuznetsov, V.; Laget, J. M.; Langheinrich, J.; Lawrence, D.; Lima, A. C. S.; Livingston, K.; Lowry, M.; Lu, H. Y.; Lukashin, K.; MacCormick, M.; Malace, S.; Manak, J. J.; Markov, N.; Mattione, P.; McAleer, S.; McCracken, M. E.; McKinnon, B.; McNabb, J. W. C.; Mecking, B. A.; Mestayer, M. D.; Meyer, C. A.; Mibe, T.; Mikhailov, K.; Mineeva, T.; Minehart, R.; Mirazita, M.; Miskimen, R.; Mokeev, V.; Moreno, B.; Moriya, K.; Morrow, S. A.; Moteabbed, M.; Mueller, J.; Munevar, E.; Mutchler, G. S.; Nadel-Turonski, P.; Nasseripour, R.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Niczyporuk, B. B.; Niroula, M. R.; Niyazov, R. A.; Nozar, M.; O'Rielly, G. V.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Park, S.; Pasyuk, E.; Paterson, C.; Pereira, S. Anefalos; Philips, S. A.; Pierce, J.; Pivnyuk, N.; Pocanic, D.; Pogorelko, O.; Polli, E.; Popa, I.; Pozdniakov, S.; Preedom, B. M.; Price, J. W.; Prok, Y.; Protopopescu, D.; Qin, L. M.; Raue, B. A.; Riccardi, G.; Ricco, G.; Ripani, M.; Ritchie, B. G.; Rosner, G.; Rossi, P.; Rowntree, D.; Rubin, P. D.; Sabatié, F.; Saini, M. S.; Salamanca, J.; Salgado, C.; Sandorfi, A.; Santoro, J. P.; Sapunenko, V.; Schott, D.; Schumacher, R. A.; Serov, V. S.; Sharabian, Y. G.; Sharov, D.; Shaw, J.; Shvedunov, N. V.; Skabelin, A. V.; Smith, E. S.; Smith, L. C.; Sober, D. I.; Sokhan, D.; Starostin, A.; Stavinsky, A.; Stepanyan, S.; Stepanyan, S. S.; Stokes, B. E.; Stoler, P.; Stopani, K. A.; Strakovsky, I. I.; Strauch, S.; Suleiman, R.; Taiuti, M.; Taylor, S.; Tedeschi, D. J.; Thompson, R.; Tkabladze, A.; Tkachenko, S.; Ungaro, M.; Vlassov, A. V.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Weygand, D. P.; Williams, M.; Wolin, E.; Wood, M. H.; Yegneswaran, A.; Yun, J.; Yurov, M.; Zana, L.; Zhang, J.; Zhao, B.; Zhao, Z. W.

    2009-05-01

    The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q2=1.0-4.8GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.

  10. Precise measurement of the neutron magnetic form factor G(M)n in the few-GeV2 region.

    PubMed

    Lachniet, J; Afanasev, A; Arenhövel, H; Brooks, W K; Gilfoyle, G P; Higinbotham, D; Jeschonnek, S; Quinn, B; Vineyard, M F; Adams, G; Adhikari, K P; Amaryan, M J; Anghinolfi, M; Asavapibhop, B; Asryan, G; Avakian, H; Bagdasaryan, H; Baillie, N; Ball, J P; Baltzell, N A; Barrow, S; Batourine, V; Battaglieri, M; Beard, K; Bedlinskiy, I; Bektasoglu, M; Bellis, M; Benmouna, N; Berman, B L; Biselli, A S; Bonner, B E; Bookwalter, C; Bouchigny, S; Boiarinov, S; Bradford, R; Branford, D; Briscoe, W J; Bültmann, S; Burkert, V D; Calarco, J R; Careccia, S L; Carman, D S; Casey, L; Cheng, L; Cole, P L; Coleman, A; Collins, P; Cords, D; Corvisiero, P; Crabb, D; Crede, V; Cummings, J P; Dale, D; Daniel, A; Dashyan, N; De Masi, R; De Vita, R; De Sanctis, E; Degtyarenko, P V; Denizli, H; Dennis, L; Deur, A; Dhamija, S; Dharmawardane, K V; Dhuga, K S; Dickson, R; Djalali, C; Dodge, G E; Doughty, D; Dragovitsch, P; Dugger, M; Dytman, S; Dzyubak, O P; Egiyan, H; Egiyan, K S; El Fassi, L; Elouadrhiri, L; Empl, A; Eugenio, P; Fatemi, R; Fedotov, G; Fersch, R; Feuerbach, R J; Forest, T A; Fradi, A; Gabrielyan, M Y; Garçon, M; Gavalian, G; Gevorgyan, N; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Griffioen, K A; Guidal, M; Guillo, M; Guler, N; Guo, L; Gyurjyan, V; Hadjidakis, C; Hafidi, K; Hakobyan, H; Hanretty, C; Hardie, J; Hassall, N; Heddle, D; Hersman, F W; Hicks, K; Hleiqawi, I; Holtrop, M; Hu, J; Huertas, M; Hyde-Wright, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Ito, M M; Jenkins, D; Jo, H S; Johnstone, J R; Joo, K; Juengst, H G; Kageya, T; Kalantarians, N; Keller, D; Kellie, J D; Khandaker, M; Khetarpal, P; Kim, K Y; Kim, K; Kim, W; Klein, A; Klein, F J; Klusman, M; Konczykowski, P; Kossov, M; Kramer, L H; Kubarovsky, V; Kuhn, J; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Laget, J M; Langheinrich, J; Lawrence, D; Lima, A C S; Livingston, K; Lowry, M; Lu, H Y; Lukashin, K; Maccormick, M; Malace, S; Manak, J J; Markov, N; Mattione, P; McAleer, S; McCracken, M E; McKinnon, B; McNabb, J W C; Mecking, B A; Mestayer, M D; Meyer, C A; Mibe, T; Mikhailov, K; Mineeva, T; Minehart, R; Mirazita, M; Miskimen, R; Mokeev, V; Moreno, B; Moriya, K; Morrow, S A; Moteabbed, M; Mueller, J; Munevar, E; Mutchler, G S; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Niczyporuk, B B; Niroula, M R; Niyazov, R A; Nozar, M; O'Rielly, G V; Osipenko, M; Ostrovidov, A I; Park, K; Park, S; Pasyuk, E; Paterson, C; Pereira, S Anefalos; Philips, S A; Pierce, J; Pivnyuk, N; Pocanic, D; Pogorelko, O; Polli, E; Popa, I; Pozdniakov, S; Preedom, B M; Price, J W; Prok, Y; Protopopescu, D; Qin, L M; Raue, B A; Riccardi, G; Ricco, G; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Rowntree, D; Rubin, P D; Sabatié, F; Saini, M S; Salamanca, J; Salgado, C; Sandorfi, A; Santoro, J P; Sapunenko, V; Schott, D; Schumacher, R A; Serov, V S; Sharabian, Y G; Sharov, D; Shaw, J; Shvedunov, N V; Skabelin, A V; Smith, E S; Smith, L C; Sober, D I; Sokhan, D; Starostin, A; Stavinsky, A; Stepanyan, S; Stepanyan, S S; Stokes, B E; Stoler, P; Stopani, K A; Strakovsky, I I; Strauch, S; Suleiman, R; Taiuti, M; Taylor, S; Tedeschi, D J; Thompson, R; Tkabladze, A; Tkachenko, S; Ungaro, M; Vlassov, A V; Watts, D P; Wei, X; Weinstein, L B; Weygand, D P; Williams, M; Wolin, E; Wood, M H; Yegneswaran, A; Yun, J; Yurov, M; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

    2009-05-15

    The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data. PMID:19518944

  11. Updating the tritium quality factor: the argument for conservatism

    SciTech Connect

    Till, J E; Etnier, E L; Meyer, H R

    1980-01-01

    Estimated doses resulting from tritium releases to the environment are linearly dependent upon the quality factor (Q) chosen for tritium beta radiation. In 1969 the International Commission on Radiological Protection (ICRP) recommended using 1 as the Q for all low energy beta radiation. Considerable improvements have been made in evaluating exposures to tritium at very low dose rates and in refining physiological and biological endpoints since the 1969 ICRP recommendations. This study summarizes recent experiments to determine the relative biological effectiveness of tritium. Based upon our study of published data related to quality factor, its importance in the calculation of dose, and the currently accepted conservative philosophy in radiation protection, it is concluded that a value of 2 would seem to be more defensible for environmental assessments and that a reevaluation of the tritium quality factor by the ICRP is needed.

  12. High quality factor, fully switchable terahertz superconducting metasurface

    SciTech Connect

    Scalari, G. Maissen, C.; Faist, J.; Cibella, S.; Leoni, R.

    2014-12-29

    We present a complementary THz metasurface realised with Niobium thin film which displays a quality factor Q = 54 and a fully switchable behaviour as a function of the temperature. The switching behaviour and the high quality factor are due to a careful design of the metasurface aimed at maximising the ohmic losses when the Nb is above the critical temperature and minimising the radiative coupling. The superconductor allows the operation of the cavity with high Q and the use of inductive elements with a high aspect ratio. Comparison with three dimensional finite element simulations highlights the crucial role of the inductive elements and of the kinetic inductance of the Cooper pairs in achieving the high quality factor and the high field enhancement.

  13. Quality factors for space radiation: A new approach

    NASA Astrophysics Data System (ADS)

    Borak, Thomas B.; Heilbronn, Lawrence H.; Townsend, Lawrence W.; McBeth, Rafe A.; de Wet, Wouter

    2014-04-01

    NASA has derived new models for radiological risk assessment based on epidemiological data and radiation biology including differences in Relative Biological Effectiveness for leukemia and solid tumors. Comprehensive approaches were used to develop new risk cross sections and the extension of these into recommendations for risk assessment during space missions. The methodology relies on published data generated and the extensive research initiative managed by the NASA Human Research Program (HRP) and reviewed by the National Academy of Sciences. This resulted in recommendations for revised specifications of quality factors, QNASA (Z , β) in terms of track structure concepts that extend beyond LET alone. The new paradigm for quality factors placed demands on radiation monitoring procedures that are not satisfied by existing dosimetry systems or particle spectrometers that are practical for space exploration where mass, volume, band width and power consumption are highly constrained. We have proposed a new definition of quality factors that relaxes the requirements for identifying charge, Z, and velocity, β, of the incident radiation while still preserving the functional form of the inherent risk functions. The departure from the exact description of QNASA (Z , β) is that the revised values are new functions of LET for solid cancers and leukemia. We present the motivation and process for developing the revised quality factors. We describe results of extensive simulations using GCR distributions in free space as well as the resulting spectra of primary and secondary particles behind aluminum shields and penetration through water. In all cases the revised dose averaged quality factors agreed with those based on the values obtained using QNASA (Z , β). This provides confidence that emerging technologies for space radiation dosimetry can provide real time measurements of dose and dose equivalent while satisfying constraints on size, mass, power and bandwidth. The

  14. Quality factors for space radiation: A new approach.

    PubMed

    Borak, Thomas B; Heilbronn, Lawrence H; Townsend, Lawrence W; McBeth, Rafe A; de Wet, Wouter

    2014-04-01

    NASA has derived new models for radiological risk assessment based on epidemiological data and radiation biology including differences in Relative Biological Effectiveness for leukemia and solid tumors. Comprehensive approaches were used to develop new risk cross sections and the extension of these into recommendations for risk assessment during space missions. The methodology relies on published data generated and the extensive research initiative managed by the NASA Human Research Program (HRP) and reviewed by the National Academy of Sciences. This resulted in recommendations for revised specifications of quality factors, QNASA(Z,β) in terms of track structure concepts that extend beyond LET alone. The new paradigm for quality factors placed demands on radiation monitoring procedures that are not satisfied by existing dosimetry systems or particle spectrometers that are practical for space exploration where mass, volume, band width and power consumption are highly constrained. We have proposed a new definition of quality factors that relaxes the requirements for identifying charge, Z, and velocity, β, of the incident radiation while still preserving the functional form of the inherent risk functions. The departure from the exact description of QNASA(Z,β) is that the revised values are new functions of LET for solid cancers and leukemia. We present the motivation and process for developing the revised quality factors. We describe results of extensive simulations using GCR distributions in free space as well as the resulting spectra of primary and secondary particles behind aluminum shields and penetration through water. In all cases the revised dose averaged quality factors agreed with those based on the values obtained using QNASA(Z,β). This provides confidence that emerging technologies for space radiation dosimetry can provide real time measurements of dose and dose equivalent while satisfying constraints on size, mass, power and bandwidth. The revised

  15. Human factors systems approach to healthcare quality and patient safety

    PubMed Central

    Carayon, Pascale; Wetterneck, Tosha B.; Rivera-Rodriguez, A. Joy; Hundt, Ann Schoofs; Hoonakker, Peter; Holden, Richard; Gurses, Ayse P.

    2013-01-01

    Human factors systems approaches are critical for improving healthcare quality and patient safety. The SEIPS (Systems Engineering Initiative for Patient Safety) model of work system and patient safety is a human factors systems approach that has been successfully applied in healthcare research and practice. Several research and practical applications of the SEIPS model are described. Important implications of the SEIPS model for healthcare system and process redesign are highlighted. Principles for redesigning healthcare systems using the SEIPS model are described. Balancing the work system and encouraging the active and adaptive role of workers are key principles for improving healthcare quality and patient safety. PMID:23845724

  16. Quality of Working Life of Nurses and its Related Factors

    PubMed Central

    Moradi, Tayebeh; Maghaminejad, Farzaneh; Azizi-Fini, Ismail

    2014-01-01

    Background: Nurses as the largest group of health care providers should enjoy a satisfactory quality of working life to be able to provide quality care to their patients. Therefore, attention should be paid to the nurses’ working life. Objectives: This study aimed to investigate the quality of nurses' working life in Kashans' hospitals during 2012. Materials and Methods: This cross-sectional study was conducted on 200 nurses during 2012. The data-gathering instrument consisted of two parts. The first part consisted of questions on demographic information and the second part was the Walton’s quality of work life questionnaire. Data were analyzed using the SPSS software. For statistical analysis T test and one way ANOVA were used. Results: The results of the study showed that 60% of nurses reported that they had moderate level of quality of working life while 37.1% and 2% had undesirable and good quality of working life, respectively. Nurses with associate degrees reported a better quality of working life than others. A significant relationship was found between variables such as education level, work experience, and type of hospital with quality of working life score (P < 0.05). No significant differences were observed between quality of working life score of nurses with employment status (P = 0.061), salary (P = 0.052), age, gender and marital status (P > 0.05). Conclusions: Nurses' quality of work life was at the moderate level. As quality of work life has an important impact on attracting and retaining employees, it is necessary to pay more attention to the nurses’ quality of work life and its affecting factors. PMID:25414904

  17. High Quality Factor Mechanical Resonators Based on WSe2 Monolayers.

    PubMed

    Morell, Nicolas; Reserbat-Plantey, Antoine; Tsioutsios, Ioannis; Schädler, Kevin G; Dubin, François; Koppens, Frank H L; Bachtold, Adrian

    2016-08-10

    Suspended monolayer transition metal dichalcogenides (TMD) are membranes that combine ultralow mass and exceptional optical properties, making them intriguing materials for opto-mechanical applications. However, the low measured quality factor of TMD resonators has been a roadblock so far. Here, we report an ultrasensitive optical readout of monolayer TMD resonators that allows us to reveal their mechanical properties at cryogenic temperatures. We find that the quality factor of monolayer WSe2 resonators greatly increases below room temperature, reaching values as high as 1.6 × 10(4) at liquid nitrogen temperature and 4.7 × 10(4) at liquid helium temperature. This surpasses the quality factor of monolayer graphene resonators with similar surface areas. Upon cooling the resonator, the resonant frequency increases significantly due to the thermal contraction of the WSe2 lattice. These measurements allow us to experimentally study the thermal expansion coefficient of WSe2 monolayers for the first time. High Q-factors are also found in resonators based on MoS2 and MoSe2 monolayers. The high quality-factor found in this work opens new possibilities for coupling mechanical vibrational states to two-dimensional excitons, valley pseudospins, and single quantum emitters and for quantum opto-mechanical experiments based on the Casimir interaction. PMID:27459399

  18. Measurement of the Neutron electric form factor at Q2=0.8 2(GeV\\\\c)

    SciTech Connect

    Derek Glazier

    2007-09-30

    Nucleon form factors allow a sensitive test for models of the nucleon. Recent experiments utilising polarisation observables have resulted, for the first time, in a model-independent determination of the neutron electric form factor GnE. This method employed an 80% longitudinally polarised, high intensity (10 uA) electon beam (883 MeV) that was quasi-elastically scattered off a liquid deuterium target in the reaction D (e, en)p. A neutron polarimeter was designed and installed to measure the ratio of transverse-to-longitudinal polarisation using neutron scattering asymmetries. This ratio allowed a determination of the neutron elastic form factor, GnE, free of the previous large systematic uncertainties associated with the deuterium wave function. The experiment took place in the A1 experimental hall at MAMI taking advantage of a high resolution magnetic spectrometer. A detailed investigation was carried out into the performance of the neutron polarimeter.

  19. Realization of high quality production schedules: Structuring quality factors via iteration of user specification processes

    NASA Technical Reports Server (NTRS)

    Hamazaki, Takashi

    1992-01-01

    This paper describes an architecture for realizing high quality production schedules. Although quality is one of the most important aspects of production scheduling, it is difficult, even for a user, to specify precisely. However, it is also true that the decision as to whether a scheduler is good or bad can only be made by the user. This paper proposes the following: (1) the quality of a schedule can be represented in the form of quality factors, i.e. constraints and objectives of the domain, and their structure; (2) quality factors and their structure can be used for decision making at local decision points during the scheduling process; and (3) that they can be defined via iteration of user specification processes.

  20. The Average Quality Factors by TEPC for Charged Particles

    NASA Technical Reports Server (NTRS)

    Kim, Myung-Hee Y.; Nikjoo, Hooshang; Cucinotta, Francis A.

    2004-01-01

    The quality factor used in radiation protection is defined as a function of LET, Q(sub ave)(LET). However, tissue equivalent proportional counters (TEPC) measure the average quality factors as a function of lineal energy (y), Q(sub ave)(Y). A model of the TEPC response for charged particles considers energy deposition as a function of impact parameter from the ion s path to the volume, and describes the escape of energy out of sensitive volume by delta-rays and the entry of delta rays from the high-density wall into the low-density gas-volume. A common goal for operational detectors is to measure the average radiation quality to within accuracy of 25%. Using our TEPC response model and the NASA space radiation transport model we show that this accuracy is obtained by a properly calibrated TEPC. However, when the individual contributions from trapped protons and galactic cosmic rays (GCR) are considered; the average quality factor obtained by TEPC is overestimated for trapped protons and underestimated for GCR by about 30%, i.e., a compensating error. Using TEPC's values for trapped protons for Q(sub ave)(y), we obtained average quality factors in the 2.07-2.32 range. However, Q(sub ave)(LET) ranges from 1.5-1.65 as spacecraft shielding depth increases. The average quality factors for trapped protons on STS-89 demonstrate that the model of the TEPC response is in good agreement with flight TEPC data for Q(sub ave)(y), and thus Q(sub ave)(LET) for trapped protons is overestimated by TEPC. Preliminary comparisons for the complete GCR spectra show that Q(sub ave)(LET) for GCR is approximately 3.2-4.1, while TEPC measures 2.9-3.4 for QQ(sub ave)(y), indicating that QQ(sub ave)(LET) for GCR is underestimated by TEPC.

  1. Identifying Key Hospital Service Quality Factors in Online Health Communities

    PubMed Central

    Jung, Yuchul; Hur, Cinyoung; Jung, Dain

    2015-01-01

    Background The volume of health-related user-created content, especially hospital-related questions and answers in online health communities, has rapidly increased. Patients and caregivers participate in online community activities to share their experiences, exchange information, and ask about recommended or discredited hospitals. However, there is little research on how to identify hospital service quality automatically from the online communities. In the past, in-depth analysis of hospitals has used random sampling surveys. However, such surveys are becoming impractical owing to the rapidly increasing volume of online data and the diverse analysis requirements of related stakeholders. Objective As a solution for utilizing large-scale health-related information, we propose a novel approach to identify hospital service quality factors and overtime trends automatically from online health communities, especially hospital-related questions and answers. Methods We defined social media–based key quality factors for hospitals. In addition, we developed text mining techniques to detect such factors that frequently occur in online health communities. After detecting these factors that represent qualitative aspects of hospitals, we applied a sentiment analysis to recognize the types of recommendations in messages posted within online health communities. Korea’s two biggest online portals were used to test the effectiveness of detection of social media–based key quality factors for hospitals. Results To evaluate the proposed text mining techniques, we performed manual evaluations on the extraction and classification results, such as hospital name, service quality factors, and recommendation types using a random sample of messages (ie, 5.44% (9450/173,748) of the total messages). Service quality factor detection and hospital name extraction achieved average F1 scores of 91% and 78%, respectively. In terms of recommendation classification, performance (ie, precision) is

  2. Measurement of the neutron electric form factor GEn in quasielastic scattering

    SciTech Connect

    Donal Day

    2003-07-15

    We have measured the electric form factor of the neutron, GEn, at two momentum transfers (Q2= 0.5 and Q2= 1.0 GeV/c2) through quasielastic scattering in Jefferson Lab's Hall C. Longitudinally polarized electrons scattered from polarized deuterated ammonia and GEn was extracted from the beam-target asymmetry AVed which, in quasielastic kinematics, is particularly sensitive to GEn and insensitive to MEC and FSI.

  3. Factors Influencing Practical Training Quality in Iranian Agricultural Higher Education

    ERIC Educational Resources Information Center

    Mojarradi, Gholamreza; Karamidehkordi, Esmail

    2016-01-01

    This paper presents an analysis of the factors influencing the practical training quality of agricultural higher education programmes from the senior students' perspective. The study was conducted in two public universities located in the north-west of Iran using a cross-sectional survey and structured interviews with a randomised sample of 254…

  4. Nuclear reaction effects in use of newly recommended quality factor

    NASA Technical Reports Server (NTRS)

    Shinn, Judy L.; Wilson, John W.

    1991-01-01

    The biological risk for energetic ion exposure cannot be reliably estimated exclusive of the target nuclear reaction products produced within the local tissue. A theoretical basis is derived for evaluating target fragment contributions that are evaluated for the newly proposed quality factor.

  5. Comparison of the mean quality factors for astronauts calculated using the Q-functions proposed by ICRP, ICRU, and NASA

    NASA Astrophysics Data System (ADS)

    Sato, T.; Endo, A.; Niita, K.

    2013-07-01

    For the estimation of the radiation risk for astronauts, not only the organ absorbed doses but also their mean quality factors must be evaluated. Three functions have been proposed by different organizations for expressing the radiation quality, including the Q(L), Q(y), and QNASA(Z, E) relationships as defined in International Committee of Radiological Protection (ICRP) Publication 60, International Commission on Radiation Units and Measurements (ICRU) Report 40, and National Aeronautics and Space Administration (NASA) TP-2011-216155, respectively. The Q(L) relationship is the most simple and widely used for space dosimetry, but the use of the latter two functions enables consideration of the difference in the track structure of various charged particles during the risk estimation. Therefore, we calculated the mean quality factors in organs and tissues in ICRP/ICRU reference voxel phantoms for the isotropic exposure to various mono-energetic particles using the three Q-functions. The Particle and Heavy Ion Transport code System PHITS was employed to simulate the particle motions inside the phantoms. The effective dose equivalents and the phantom-averaged effective quality factors for the astronauts were then estimated from the calculated mean quality factors multiplied by the fluence-to-dose conversion coefficients and cosmic-ray fluxes inside a spacecraft. It was found from the calculations that QNASA generally gives the largest values for the phantom-averaged effective quality factors among the three Q-functions for neutron, proton, and lighter-ion irradiation, whereas Q(L) provides the largest values for heavier-ion irradiation. Overall, the introduction of QNASA instead of Q(L) or Q(y) in astronaut dosimetry results in the increase the effective dose equivalents because the majority of the doses are composed of the contributions from protons and neutrons, although this tendency may change by the calculation conditions.

  6. Journal quality metrics: options to consider other than impact factors.

    PubMed

    Brown, Ted

    2011-01-01

    Journal quality metrics (also referred to as bibliometrics), such as impact factors, are increasingly being used as a measure of researchers' and educators' success and prestige. Occupational therapists who submit articles to peer-reviewed journals may face a professional and research dilemma: Do they submit their articles to journals that largely have a professional audience and potentially do not have an impact factor, or do they opt not to publish their research material in occupational therapy-oriented journals? Occupational therapy authors can consider other journal quality metric alternatives, in addition to the impact factor option, including the Eigenfactor Score, Article Influence Score, h-index, SCImago Journal Rank (SJR), Source Normalised Impact per Paper (SNIP), and discipline-specific generated journal quality measures. These other journal quality metrics can be important reference points for occupational therapists who publish and may encourage authors to publish in journals relevant to the discipline. This process, in turn, will build the occupational therapy body of knowledge as well as provide an essential, growing reference source for evidence-based practice. PMID:21675341

  7. Preliminary Study for a Tetrahedron Formation: Quality Factors and Visualization

    NASA Technical Reports Server (NTRS)

    Guzman, Jose J.; Schiff, Conrad; Bauer, Frank (Technical Monitor)

    2002-01-01

    Spacecraft flying in tetrahedron formations are excellent for electromagnetic and plasma studies. The quality of the science recorded is strongly affected by the tetrahedron evolution. This paper is a preliminary study on the computation of quality factors and visualization for a formation of four or five satellites. Four of the satellites are arranged geometrically in a tetrahedron shape. If a fifth satellite is present, it is arbitrarily initialized at the geometric center of the tetrahedron. The fifth satellite could act as a collector or as a spare spacecraft. Tetrahedron natural coordinates are employed for the initialization. The natural orbit evolution is visualized in geocentric equatorial inertial and in geocentric solar magnetospheric coordinates.

  8. A polarized target measurement of the electric form factor of the neutron at Jlab

    SciTech Connect

    N. Savvinov

    2004-09-01

    The experiment E93-026 at the Thomas Jefferson National Accelerator Facility (JLab) determined the electric form factor of the neutron G{sub E}{sup n} through quasielastic {rvec d}({rvec e},e'n)p scattering using a longitudinally polarized electron beam and a frozen polarized {sup 15}N D{sub 3} target. The knocked out neutrons were detected in a segmented plastic scintillator detector in coincidence with the scattered electrons. The G{sub E}{sup n} was extracted by comparing the experimental beam-target asymmetry with full theoretical calculations based on different values of G{sub E}{sup n}. Preliminary results of the Fall 2001 run are reported.

  9. Boron Neutron Capture Therapy (BNCT) Dose Calculation using Geometrical Factors Spherical Interface for Glioblastoma Multiforme

    NASA Astrophysics Data System (ADS)

    Zasneda, Sabriani; Widita, Rena

    2010-06-01

    Boron Neutron Capture Therapy (BNCT) is a cancer therapy by utilizing thermal neutron to produce alpha particles and lithium nuclei. The superiority of BNCT is that the radiation effects could be limited only for the tumor cells. BNCT radiation dose depends on the distribution of boron in the tumor. Absorbed dose to the cells from the reaction 10B (n, α) 7Li was calculated near interface medium containing boron and boron-free region. The method considers the contribution of the alpha particle and recoiled lithium particle to the absorbed dose and the variation of Linear Energy Transfer (LET) charged particles energy. Geometrical factor data of boron distribution for the spherical surface is used to calculate the energy absorbed in the tumor cells, brain and scalp for case Glioblastoma Multiforme. The result shows that the optimal dose in tumor is obtained for boron concentrations of 22.1 mg 10B/g blood.

  10. Boron Neutron Capture Therapy (BNCT) Dose Calculation using Geometrical Factors Spherical Interface for Glioblastoma Multiforme

    SciTech Connect

    Zasneda, Sabriani; Widita, Rena

    2010-06-22

    Boron Neutron Capture Therapy (BNCT) is a cancer therapy by utilizing thermal neutron to produce alpha particles and lithium nuclei. The superiority of BNCT is that the radiation effects could be limited only for the tumor cells. BNCT radiation dose depends on the distribution of boron in the tumor. Absorbed dose to the cells from the reaction 10B (n, {alpha}) 7Li was calculated near interface medium containing boron and boron-free region. The method considers the contribution of the alpha particle and recoiled lithium particle to the absorbed dose and the variation of Linear Energy Transfer (LET) charged particles energy. Geometrical factor data of boron distribution for the spherical surface is used to calculate the energy absorbed in the tumor cells, brain and scalp for case Glioblastoma Multiforme. The result shows that the optimal dose in tumor is obtained for boron concentrations of 22.1 mg {sup 10}B/g blood.

  11. Measurement of the anomalous neutron orbital g factor in /sup 190//sup m/Os

    SciTech Connect

    Beck, R.; Eder, R.; Hagn, E.; Zech, E.

    1987-12-28

    The magnetic moment of /sup 190//sup m/Os (I/sup ..pi../ = 10/sup -/; T/sub 1/2/ = 9.9 min; E = 1705 keV configuration chemically bondn/sub 1/9/2(505)n/sub 2/11/2(615)>/sub 10-/ has been measured with the new technique of reorientation--nuclear-orientation. As the spin contributions of the two neutrons to the magnetic moment cancel almost completely, it is possible to determine the anomalous neutron orbital g factor directly. The result, -0.12less than or equal todeltag/sub 1/(n)less than or equal to0.07 (90% confidence level) tends to be larger than deltag/sub 1/(n)approx. =-0.05 adopted up to now.

  12. The study of surgical image quality evaluation system by subjective quality factor method

    NASA Astrophysics Data System (ADS)

    Zhang, Jian J.; Xuan, Jason R.; Yang, Xirong; Yu, Honggang; Koullick, Edouard

    2016-03-01

    GreenLightTM procedure is an effective and economical way of treatment of benign prostate hyperplasia (BPH); there are almost a million of patients treated with GreenLightTM worldwide. During the surgical procedure, the surgeon or physician will rely on the monitoring video system to survey and confirm the surgical progress. There are a few obstructions that could greatly affect the image quality of the monitoring video, like laser glare by the tissue and body fluid, air bubbles and debris generated by tissue evaporation, and bleeding, just to name a few. In order to improve the physician's visual experience of a laser surgical procedure, the system performance parameter related to image quality needs to be well defined. However, since image quality is the integrated set of perceptions of the overall degree of excellence of an image, or in other words, image quality is the perceptually weighted combination of significant attributes (contrast, graininess …) of an image when considered in its marketplace or application, there is no standard definition on overall image or video quality especially for the no-reference case (without a standard chart as reference). In this study, Subjective Quality Factor (SQF) and acutance are used for no-reference image quality evaluation. Basic image quality parameters, like sharpness, color accuracy, size of obstruction and transmission of obstruction, are used as subparameter to define the rating scale for image quality evaluation or comparison. Sample image groups were evaluated by human observers according to the rating scale. Surveys of physician groups were also conducted with lab generated sample videos. The study shows that human subjective perception is a trustworthy way of image quality evaluation. More systematic investigation on the relationship between video quality and image quality of each frame will be conducted as a future study.

  13. Boron carbide coatings for neutron detection probed by x-rays, ions, and neutrons to determine thin film quality

    SciTech Connect

    Nowak, G. Störmer, M.; Horstmann, C.; Kampmann, R.; Höche, D.; Lorenz, U.; Müller, M.; Schreyer, A.; Becker, H.-W.; Haese-Seiller, M.; Moulin, J.-F.; Pomm, M.; Randau, C.; Hall-Wilton, R.

    2015-01-21

    Due to the present shortage of {sup 3}He and the associated tremendous increase of its price, the supply of large neutron detection systems with {sup 3}He becomes unaffordable. Alternative neutron detection concepts, therefore, have been invented based on solid {sup 10}B converters. These concepts require development in thin film deposition technique regarding high adhesion, thickness uniformity and chemical purity of the converter coating on large area substrates. We report on the sputter deposition of highly uniform large-area {sup 10}B{sub 4}C coatings of up to 2 μm thickness with a thickness deviation below 4% using the Helmholtz-Zentrum Geesthacht large area sputtering system. The {sup 10}B{sub 4}C coatings are x-ray amorphous and highly adhesive to the substrate. Material analysis by means of X-ray-Photoelectron Spectroscopy, Secondary-Ion-Mass-Spectrometry, and Rutherford-Back-Scattering (RBS) revealed low impurities concentration in the coatings. The isotope composition determined by Secondary-Ion-Mass-Spectrometry, RBS, and inelastic nuclear reaction analysis of the converter coatings evidences almost identical {sup 10}B isotope contents in the sputter target and in the deposited coating. Neutron conversion and detection test measurements with variable irradiation geometry of the converter coating demonstrate an average relative quantum efficiency ranging from 65% to 90% for cold neutrons as compared to a black {sup 3}He-monitor. Thus, these converter coatings contribute to the development of {sup 3}He-free prototype detectors based on neutron grazing incidence. Transferring the developed coating process to an industrial scale sputtering system can make alternative {sup 3}He-free converter elements available for large area neutron detection systems.

  14. Boron carbide coatings for neutron detection probed by x-rays, ions, and neutrons to determine thin film quality

    NASA Astrophysics Data System (ADS)

    Nowak, G.; Störmer, M.; Becker, H.-W.; Horstmann, C.; Kampmann, R.; Höche, D.; Haese-Seiller, M.; Moulin, J.-F.; Pomm, M.; Randau, C.; Lorenz, U.; Hall-Wilton, R.; Müller, M.; Schreyer, A.

    2015-01-01

    Due to the present shortage of 3He and the associated tremendous increase of its price, the supply of large neutron detection systems with 3He becomes unaffordable. Alternative neutron detection concepts, therefore, have been invented based on solid 10B converters. These concepts require development in thin film deposition technique regarding high adhesion, thickness uniformity and chemical purity of the converter coating on large area substrates. We report on the sputter deposition of highly uniform large-area 10B4C coatings of up to 2 μm thickness with a thickness deviation below 4% using the Helmholtz-Zentrum Geesthacht large area sputtering system. The 10B4C coatings are x-ray amorphous and highly adhesive to the substrate. Material analysis by means of X-ray-Photoelectron Spectroscopy, Secondary-Ion-Mass-Spectrometry, and Rutherford-Back-Scattering (RBS) revealed low impurities concentration in the coatings. The isotope composition determined by Secondary-Ion-Mass-Spectrometry, RBS, and inelastic nuclear reaction analysis of the converter coatings evidences almost identical 10B isotope contents in the sputter target and in the deposited coating. Neutron conversion and detection test measurements with variable irradiation geometry of the converter coating demonstrate an average relative quantum efficiency ranging from 65% to 90% for cold neutrons as compared to a black 3He-monitor. Thus, these converter coatings contribute to the development of 3He-free prototype detectors based on neutron grazing incidence. Transferring the developed coating process to an industrial scale sputtering system can make alternative 3He-free converter elements available for large area neutron detection systems.

  15. Sociodemographic factors and the quality of prenatal care.

    PubMed Central

    Hansell, M J

    1991-01-01

    BACKGROUND: In this study, maternal sociodemographic factors are examined in relationship to the quality of prenatal health services US women receive. METHODS: Data from the 1980 National Natality Survey and 1980 Fetal Mortality Survey were used for the analysis. Indicator variables for prenatal care quality are the percentages of prenatal visits at which blood pressure and urine were tested, the performance of hemoglobin or hematocrit tests, and the presence or absence of advice regarding salt restriction and diuretics usage during pregnancy. RESULTS: Distribution of the basic examinations in prenatal care vary according to marital status, parity, education, and residence in a metropolitan or nonmetropolitan county. The advice received concerning salt and diuretics usage was also influenced by sociodemographic variables. CONCLUSIONS: The analyses reveal that prenatal care is not of even minimally acceptable quality for many women. PMID:1953875

  16. Measured neutron carbon kerma factors from 14. 1 MeV to 18 MeV

    SciTech Connect

    Deluca, P.M. Jr.; Barschall, H.H.; Haight, R.C.; McDonald, J.C.

    1984-01-01

    For A-150 tissue-equivalent plastic, the total neutron kerma is dominated by the hydrogen kerma. Tissue kerma is inferred with reasonable accuracy by normalization to the kerma factor ratio between tissue and A-150 plastic. Because of the close match in the hydrogen abundance in these materials, the principal uncertainty is due to the kerma factors of carbon and oxygen. We have measured carbon kerma factor values of 0.183 +- 0.015 10/sup -8/ cGy cm/sup 2/ and 0.210 +- 0.16 10/sup -8/ cGy cm/sup 2/ at 14.1-MeV and 15-MeV neutron energy, respectively. A preliminary value of 0.297 +- 0.03 10/sup -8/ cGy cm/sup 2/ has been determined at 17.9 MeV. A recent microscopic cross section measurement of the (n,n'3..cap alpha..) reaction in carbon at 14.1-MeV energy gives a kerma factor of 0.184 +- 0.019 10/sup 8/ cGy cm/sup 2/ in agreement with the present result. 9 refs., 4 figs., 2 tabs.

  17. Quality factor of secondary cosmic radiation at flight altitudes

    NASA Astrophysics Data System (ADS)

    Burda, O.; Sato, T.; Wissmann, F.

    2013-06-01

    Dosimetry at aviation altitudes requires instruments that are able to measure the dose contributions of all field components. Tissue-equivalent proportional counters (TEPCs) are well suited for this task. From the measured lineal energy distribution, the absorbed dose and the dose equivalent can be obtained. The ratio of both quantities is named the quality factor, which is a measure of the biological effectiveness of the radiation field. The results of this work show that the mean quality factors obtained by using a TEPC are independent of the altitude, at least at altitudes between flight level (FL) 300 and FL 400, but show a significant dependence on the vertical cutoff rigidity. From a numerical simulation of the radiation field inside an aircraft, the influence of the aircraft structure can be shown.

  18. Quality factor of secondary cosmic radiation at flight altitudes.

    PubMed

    Burda, O; Sato, T; Wissmann, F

    2013-06-01

    Dosimetry at aviation altitudes requires instruments that are able to measure the dose contributions of all field components. Tissue-equivalent proportional counters (TEPCs) are well suited for this task. From the measured lineal energy distribution, the absorbed dose and the dose equivalent can be obtained. The ratio of both quantities is named the quality factor, which is a measure of the biological effectiveness of the radiation field. The results of this work show that the mean quality factors obtained by using a TEPC are independent of the altitude, at least at altitudes between flight level (FL) 300 and FL 400, but show a significant dependence on the vertical cutoff rigidity. From a numerical simulation of the radiation field inside an aircraft, the influence of the aircraft structure can be shown. PMID:23480894

  19. Method for determining formation quality factor from seismic data

    DOEpatents

    Taner, M. Turhan; Treitel, Sven

    2005-08-16

    A method is disclosed for calculating the quality factor Q from a seismic data trace. The method includes calculating a first and a second minimum phase inverse wavelet at a first and a second time interval along the seismic data trace, synthetically dividing the first wavelet by the second wavelet, Fourier transforming the result of the synthetic division, calculating the logarithm of this quotient of Fourier transforms and determining the slope of a best fit line to the logarithm of the quotient.

  20. Improving the Optical Quality Factor of the WGM Resonator

    NASA Technical Reports Server (NTRS)

    Savchenkov, Anatoliy; Matsko, Andrey; Iltchenko, Vladimir

    2008-01-01

    Resonators usually are characterized with two partially dependent values: finesse (F) and quality factor (Q). The finesse of an empty Fabry-Perot (FP) resonator is defined solely by the quality of its mirrors and is calculated as F=piR(exp 1/2)/(1-R). The maximum up-to-date value of reflectivity R approximately equal to 1 - 1.6 x 10(exp -6) is achieved with dielectric mirrors. An FP resonator made with the mirrors has finesse F=1.9 x 10(exp 6). Further practical increase of the finesse of FP resonators is problematic because of the absorption and the scattering of light in the mirror material through fundamental limit on the reflection losses given by the internal material losses and by thermodynamic density fluctuations on the order of parts in 109. The quality factor of a resonator depends on both its finesse and its geometrical size. A one-dimensional FP resonator has Q=2 F L/lambda, where L is the distance between the mirrors and lambda is the wavelength. It is easy to see that the quality factor of the resonator is unlimited because L is unlimited. F and Q are equally important. In some cases, finesse is technically more valuable than the quality factor. For instance, buildup of the optical power inside the resonator, as well as the Purcell factor, is proportional to finesse. Sometimes, however, the quality factor is more valuable. For example, inverse threshold power of intracavity hyperparametric oscillation is proportional to Q(exp 2) and efficiency of parametric frequency mixing is proportional to Q(exp 3). Therefore, it is important to know both the maximally achievable finesse and quality factor values of a resonator. Whispering gallery mode (WGM) resonators are capable of achieving larger finesse compared to FP resonators. For instance, fused silica resonators with finesse 2.3 x 10(exp 6) and 2.8 x 10(exp 6) have been demonstrated. Crystalline WGM resonators reveal even larger finesse values, F=6.3 x 10(exp 6), because of low attenuation of light in the

  1. Relationship factors and quality among mixed-orientation couples.

    PubMed

    Kays, Jill L; Yarhouse, Mark A; Ripley, Jennifer S

    2014-01-01

    Mixed-orientation couples are defined as a heterosexual couple in which 1 partner experiences same-sex attraction and the other does not. Despite the fact that there is a sizable number of mixed-orientation couples in the U.S. adult population, few researchers have studied this population, and thus, there is limited understanding of these relationships. The authors examined the degree to which relationship commitment, partner-focused forgivingness, and marital values were associated with relationship quality, and how these variables predicted relationship quality. The total sample (N = 265) consisted of 2 independent samples-105 sexual minorities (i.e., the spouse who experiences same-sex attraction) and 160 heterosexual spouses. The data were not dyadic. Together, commitment, partner-focused forgivingness, and marital values accounted for roughly 43% of the variance in relationship quality. Relationship commitment was found to be the largest single predictor of relationship quality, followed by partner-focused forgivingness. Research and clinical implications are discussed. This study significantly adds to the current research base by quantitatively measuring various variables in these relationships, as well as expanding our understanding of relationship quality in mixed-orientation couples and factors that may play a role. PMID:24328786

  2. Evaluation of gamma-ray exposure buildup factors and neutron shielding for bismuth borosilicate glasses

    NASA Astrophysics Data System (ADS)

    Singh, Vishwanath P.; Badiger, N. M.; Chanthima, N.; Kaewkhao, J.

    2014-05-01

    Gamma-ray exposure buildup factor (EBF) values and neutron shielding effectiveness of bismuth borosilicate (BBS) glass systems in composition (50-x)SiO2:15B2O3:2Al2O3:10CaO:23Na2O:xBi2O3 (where x=0, 5, 10, 15 and 20 mol%) were calculated. The EBF values were computed for photon energy 0.015-15 MeV up to penetration depths of 40 mfp (mean free path) by the geometrical progression (G-P) method. The EBF values were found dependent upon incident photon energy, penetration and bismuth molar concentration. In low- and high-energy photon regions, the EBF values were minimum whereas maximum in the intermediate-energy region. The fast neutron removal cross sections for energy 2-12 MeV were calculated by the partial density method. The BBS glass with 20 mol% Bi2O3 is found to be superior gamma-ray and neutron transparent shielding. The EBF values of the BBS glasses were compared with steel-magnetite concrete and lead. The investigation was carried out to explore the advantages of the BBS glasses in different radiation shielding applications.

  3. Influence of neutron activation factors on matrix tablets for site specific delivery to the colon.

    PubMed

    Ahrabi, S F; Heinämäki, J; Sande, S A; Graffner, C

    2000-05-01

    The impact of the neutron activation procedure, i.e. incorporation of samarium oxide (Sm(2)O(3)) and neutron irradiation, on the compression properties (including the crushing strength) and in vitro dissolution of potential colonic delivery systems based on matrix tablets of amidated pectin (Am.P) or two types of hydroxypropyl methylcellulose (HPMC) was investigated. The neutron activation factors did not influence the compression properties of the tablets. Replacement of magnesium stearate with samarium stearate in directly compressed Am.P tablets to achieve both radiolabelling and lubrication resulted in a greater extent of concentration-dependent reduction of the crushing strength. Dissolution tests demonstrated that irradiation increased the release of the model drug ropivacaine from the tablets. The extent of this increase was unexpectedly low considering the previously observed degradation of the polymer expressed as an irradiation-induced viscosity reduction in solutions prepared from the polymers. Delayed-release coating with Eudragit L 100 protected the HPMC tablets against the release-increasing effect of irradiation until the late phases of release. Sm(2)O(3) retarded the release to a varying extent depending on particle characteristics. Incorporation of Sm(2)O(3) in the coating layer did not influence the release. However, one-third of the radioactivity leached from the coating within 60 min in 0.1 M HCl. PMID:10767600

  4. His and Hers: Economic Factors and Relationship Quality in Germany.

    PubMed

    Hardie, Jessica Halliday; Geist, Claudia; Lucas, Amy

    2014-08-01

    Research has linked economic factors to relationship quality in the United States, primarily using cross-sectional data. In the current study, 2 waves of the Panel Analysis of Intimate Relationships and Family Dynamics data (n = 2,937) were used to test the gendered association between economic factors and relationship satisfaction among young German couples. In contrast to U.S.-based studies, the findings showed striking gender differences in the association between economic factors and relationship satisfaction for Germans. In cross-sectional models, women's relationship satisfaction was positively associated with receiving government economic support, and men's satisfaction was positively associated with poverty status and negatively associated with being a breadwinner. Longitudinal models revealed that changes in poverty status are associated with women's satisfaction, but men's satisfaction remains tied to their role as family provider. These unexpected results suggest that men's satisfaction is positively associated with a more equal division of labor market activity between partners. PMID:25045175

  5. Crystal fields in YbInNi4 determined with magnetic form factor and inelastic neutron scattering

    NASA Astrophysics Data System (ADS)

    Severing, A.; Givord, F.; Boucherle, J.-X.; Willers, T.; Rotter, M.; Fisk, Z.; Bianchi, A.; Fernandez-Diaz, M. T.; Stunault, A.; Rainford, B. D.; Taylor, J.; Goremychkin, E.

    2011-04-01

    The magnetic form factor of YbInNi4 has been determined via the flipping ratios R with polarized neutron diffraction, and the scattering function S(Q,ω) was measured in an inelastic neutron scattering experiment. Both experiments were performed with the aim of determining the crystal-field scheme. The magnetic form factor clearly excludes the possibility of a Γ7 doublet as the ground state. The inelastic neutron data exhibit two almost equally strong peaks at 3.2 meV and 4.4 meV which points, in agreement with earlier neutron data, toward a Γ8 quartet ground state. Further possibilities such as a quasiquartet ground state are discussed.

  6. Measurement of the Electric Form Factor of the Neutron at High Momentum Transfer

    SciTech Connect

    Jonathan Miller

    2009-06-01

    The E02-013 collaboration's precision measurement of the electric form factor of the neutron at high momentum took place in Hall A of Jefferson Laboratory [1]. Four kinematic points spread in Q2 from 1.2 to 3.5 (GeV/c)2 reach the region of momentum transfer where there is little ambiguity that the form factors are dominated by the valence quarks. The electric form factor provides important constraints on the generalized parton distributions (GPDs) of the nucleon and therefore to understand the currently unknown quark angular orbital moments. The talk presented newly obtained results for GnE including at Q2 of 2.5 (GeV/c)2. These measurements provide access to twice the range of momentum transfer for complete iso-spin decomposition of the nucleon form factors. The form factors of the u and d quarks were also presented. The measurement used a double polarization asymmetry method [2][3] with He polarized up to 55% (provided by a novel hybrid alkali optical pumping scheme utilizing a Rb & K mixture) and the highly polarized (85%) electron beam at CEBAF. A specially constructed detector package consisting of an electron spectrometer, named Big-Bite, with a solid angle of 95 msr and a large neutron detector were used to detect the particles in the reaction {sup 3}H{rvec e}({rvec e},e',h). The experimental apparatus provided more than 100 times better Figure-of-Merit than other GnE experiments utilizing polarized targets; for more information see [4].

  7. Semiconductor nano-gap antennas with high quality factor

    NASA Astrophysics Data System (ADS)

    Uemoto, Mitsuharu; Ajiki, Hiroshi

    2013-03-01

    Metallic islands with nano-gap structure are one of the most popular optical antennas. We theoretically propose a new nano-gap antenna utilizing exciton resonance of semiconductor. A light field at the nano-gap (hot spot) formed between two CuCl islands is significantly enhanced by a factor of metallic antennas. However, the hot spot of the semiconducting antenna exhibits much higher quality factor (Q ~104) at T = 40 K than those of metallic antennas which do not exceed Q ~ 100 . Our result suggests the semiconducting antenna would function as a new type of photonic cavity. The calculation method is based on a finite element method which can take into account exciton resonance. We also systematically study the geometry dependence of the enhancement factor and Q factor. In contrast to metallic antenna, blunt edges of semiconducting islands at the gap are preferable in order to achieve high enhancement factor. This is because of the fact that exciton wave function extends near the edge for blunt geometry.

  8. Health Related Quality of Life and Influencing Factors among Welders

    PubMed Central

    Qin, Jingxiang; Liu, Wuzhong; Zhu, Jun; Weng, Wei; Xu, Jiaming; Ai, Zisheng

    2014-01-01

    Background Occupational exposure to welding fumes is a serious occupational health problem all over the world. Welders are exposed to many occupational hazards; these hazards might cause some occupational diseases. The aim of the study was to assess the health related quality of life (HRQL) of electric welders in Shanghai China and explore influencing factors to HRQL of welders. Methods 301 male welders (without pneumoconiosis) and 305 non-dust male workers in Shanghai were enrolled in this study. Short Form-36 (SF-36) health survey questionnaires were applied in this cross-sectional study. Socio-demographic, working and health factors were also collected. Multiple stepwise regress analysis was used to identify significant factors related to the eight dimension scores. Results Six dimensions including role-physical (RP), bodily pain (BP), general health (GH), validity (VT), social function (SF), and mental health (MH) were significantly worse in welders compared to non-dust workers. Multiple stepwise regress analysis results show that native place, monthly income, quantity of children, drinking, sleep time, welding type, use of personal protective equipment (PPE), great events in life, and some symptoms including dizziness, discomfort of cervical vertebra, low back pain, cough and insomnia may be influencing factors for HRQL of welders. Among these factors, only sleep time and the use of PPE were salutary. Conclusions Some dimensions of HRQL of these welders have been affected. Enterprises which employ welders should take measures to protect the health of these people and improve their HRQL. PMID:25048102

  9. Reply to ``Comment on `Spectroscopic factors for bound s-wave states derived from neutron scattering lengths' ''

    NASA Astrophysics Data System (ADS)

    Mohr, P.; Herndl, H.; Oberhummer, H.; Staudt, G.

    1997-12-01

    In a recent comment Barker [Phys. Rev. C 56, 3423 (1997), the preceding paper] criticized our procedure for the extraction of spectroscopic factors from neutron scattering lengths [Phys. Rev. C 55, 1591 (1997)]. In this reply we compare the R-matrix analysis by Barker to our potential model calculation, and we discuss the applicability of both models for the extraction of spectroscopic factors.

  10. Neutron spectroscopic factors of 55Ni hole-states from (p,d) transfer reactions

    NASA Astrophysics Data System (ADS)

    Sanetullaev, A.; Tsang, M. B.; Lynch, W. G.; Lee, Jenny; Bazin, D.; Chan, K. P.; Coupland, D.; Henzl, V.; Henzlova, D.; Kilburn, M.; Rogers, A. M.; Sun, Z. Y.; Youngs, M.; Charity, R. J.; Sobotka, L. G.; Famiano, M.; Hudan, S.; Shapira, D.; Peters, W. A.; Barbieri, C.; Hjorth-Jensen, M.; Horoi, M.; Otsuka, T.; Suzuki, T.; Utsuno, Y.

    2014-09-01

    Spectroscopic information has been extracted on the hole-states of 55Ni, the least known of the quartet of nuclei (55Ni, 57Ni, 55Co and 57Cu), one nucleon away from 56Ni, the N=Z=28 double magic nucleus. Using the H1(Ni56,d)Ni55 transfer reaction in inverse kinematics, neutron spectroscopic factors, spins and parities have been extracted for the f7/2, p3/2 and the s1/2 hole-states of 55Ni. These new data provide a benchmark for large basis calculations that include nucleonic orbits in both the sd and pf shells. State of the art calculations have been performed to describe the excitation energies and spectroscopic factors of the s1/2 hole-state below Fermi energy.

  11. Surface engineering of the quality factor of metal coated microcantilevers

    SciTech Connect

    Ergincan, O.; Kooi, B. J.; Palasantzas, G.

    2014-12-14

    We performed noise measurements to obtain the quality factor (Q) and frequency shift of gold coated microcantilevers before and after surface modification using focused ion beam. As a result of our studies, it is demonstrated that surface engineering offers a promising method to control and increase the Q factor up to 50% for operation in vacuum. Surface modification could also lead to deviations from the known Q ∼ P{sup −1} behavior at low vacuum pressures P within the molecular regime. Finally, at higher pressures within the continuum regime, where Q is less sensitive to surface changes, a power scaling Q ∼ P{sup c} with c ≈ 0.3 was found instead of c = 0.5. The latter is explained via a semi-empirical formulation to account for continuum dissipation mechanisms at significant Reynolds numbers Re ∼ 1.

  12. Quality factor control in a lasing microcavity model

    PubMed

    Triandaf; Schwartz

    2000-04-01

    We consider a dynamics model of lasing microcavities, a class of optical resonators (1-10 &mgr;m in diameter) used in microlasers and for optical coupling of optical fibers. Inside such a cavity light circulates around the perimeter and is trapped by internal reflection. This is known as "whispering gallery" or high-Q modes. The cavity is a deformable cylindrical (or spherical) dielectric and at certain deformations light can escape by refraction. The quality of the resonator or Q factor, is defined as Q=omegatau, where tau is the escape time and omega is the frequency of light. We show that by appropriately deforming the cavity, the Q factor can be controlled by prolonging or shortening the average length of time spent by light trajectories inside the cavity. PMID:11088138

  13. Quality assurance program for the determination of selenium in foods and diets by instrumental neutron activation

    SciTech Connect

    Zhang, W.H.; Chatt, A.

    1996-12-31

    The biological essentially of selenium for animals was first evidenced in 1957. However, it was not until 1973 that an enzyme called glutathione peroxidase was proven to be a selenoenzyme. At present, selenium is known to be a normal component of several enzymes, proteins, and some aminoacryl transfer nucleic acids. A few selenium compounds have been reported to possess anticarcinogenic properties. There is an increasing interest in understanding the role of selenium in human nutrition and metabolism. Analytical methods are being developed in several laboratories for the determination of total and species-specific selenium in whole blood, serum, urine, soft and hard tissues, food, water, proteins, etc. We have developed several instrumental neutron activation analysis (INAA) methods using the, Dalhousie University SLOWPOKE-2 reactor facility for the determination of parts-per-billion levels of selenium. These methods include cyclic INAA (CINAA) and pseudocyclic INAA (PCINAA) using both conventional and anticoincidence gamma-ray spectrometry. Considering the immense health significance, it is imperative that the selenium levels in foods and diets be measured under an extensive quality assurance program for routine monitoring purposes.

  14. Lifestyle and semen quality: role of modifiable risk factors.

    PubMed

    Jurewicz, Joanna; Radwan, Michał; Sobala, Wojciech; Ligocka, Danuta; Radwan, Paweł; Bochenek, Michał; Hanke, Wojciech

    2014-02-01

    The relationship between exposure to lifestyle factors and adverse effects on human reproductive health is debated in the scientific literature and these controversies have increased public and regulatory attention. The aim of the study was to examine the association between modifiable lifestyle factors and main semen parameters, sperm morphology, and sperm chromatin structure. The study population consisted of 344 men who were attending an infertility clinic for diagnostic purposes with normal semen concentration of 20-300 M/ml or with slight oligozoospermia (semen total concentration of 15-20 M/ml) [WHO 1999]. Participants were interviewed and provided semen samples. The interview included questions about demographics, socio-economic status, medical history, lifestyle factors (consumption of alcohol, tobacco, coffee intake, cell phone and sauna usage), and physical activity. The results of the study suggest that lifestyle factors may affect semen quality. A negative association was found between increased body mass index (BMI) and semen volume (p = 0.03). Leisure time activity was positively associated with sperm concentration (p = 0.04) and coffee drinking with the percentage of motile sperm cells, and the percentage of sperm head and neck abnormalities (p = 0.01, p = 0.05, and p = 0.03, respectively). Drinking red wine 1-3 times per week was negatively related to sperm neck abnormalities (p = 0.01). Additionally, using a cell phone more than 10 years decreased the percentage of motile sperm cells (p = 0.02). Men who wore boxer shorts had a lower percentage of sperm neck abnormalities (p = 0.002) and percentage of sperm with DNA damage (p = 0.02). These findings may have important implications for semen quality and lifestyle. PMID:24074254

  15. Postmenopausal Women's Quality of Sleep and its Related Factors

    PubMed Central

    Taavoni, Simin; Ekbatani, Neda Nazem; Haghani, Hamid

    2015-01-01

    Aims: To asses self-reported sleep disturbance and its associated factors in 50-60-year-old Menopause women. Settings and Design: This cross sectional study included 700 healthy 50-60-year-old women volunteers who were postmenopausal for at least 1 year. The volunteers were interviewed after providing informed consent. The study questioner included two main aspects: Personal characteristics and the Pittsburgh Sleep Quality Index (PSQI). Data were analyzed by using SPSS 14 software. Results: The mean sleep scale score was 7.84 ± 4.4. Significant correlations had seen between sleep disturbance and characteristics of occupational status, educational status, husband's occupational status, and economical status, and (P = 0.002). There were no significant correlation between sleep disturbance and other personal characteristics, such as age; partner's age; number of children; family size; consumption of tea, coffee, or cola. Conclusions: Sleep disturbance is common in menopausal women. Taking into account the sleep-related personal characteristics, suitable interventions should be taken to improve sleep quality, which is a very important for maintaining the quality of life. PMID:25861204

  16. Professional quality of life and associated factors among VHA chaplains.

    PubMed

    Yan, Grace W; Beder, Joan

    2013-06-01

    Chaplains play a unique role in the Veterans Affairs (VA) health care systems and have numerous responsibilities. Compassion satisfaction (CS), compassion fatigue (CF), and burnout (BO) are three major phenomenons that have been documented in other helping professions, but little is known about VA Chaplains' professional quality of life. This study examines a national sample of VA Chaplains and their professional quality of life along with associated factors. Two-hundred and seventeen VA Chaplains completed an anonymous Internet survey, and regression analyses were conducted to determine which variables affect professional quality of life. On average, participants report high levels of CS and low levels of CF and BO. Gender, perceived support from VA administration, and mental health (MH) integration were significant predictors for CS. MH integration and perceived support significantly affected CF. Age, MH integration, and perceived support affected BO. Significant interaction effects were found for CF and BO. In summary, younger Chaplains and Chaplains who report low levels of collaboration with MH professionals are most likely to develop CF and BO. This supports continued support from the VA for interdisciplinary initiatives and mentorship of younger Chaplains. PMID:23756070

  17. Tunable high quality factor in two multimode plasmonic stubs waveguide.

    PubMed

    Chen, Zhiquan; Li, Hongjian; Zhan, Shiping; Li, Boxun; He, Zhihui; Xu, Hui; Zheng, Mingfei

    2016-01-01

    We numerically investigate the optical characteristics of a metal-dielectric-metal (MDM) waveguide side-coupled with two identical multimode stub resonators. Double plasmon-induced transparency (PIT) peaks with narrow full width at half maximum (FWHM) and high quality factor (Q-factor) can be observed in this structure. The Q-factors of PIT peaks in two stub resonators system are larger than those in single stub resonator system. A multimode coupled-radiation oscillator theory (MC-ROT), which is derived from ROT, is proposed to analyze the spectral response in the multimode system for the first time. The analytical results are confirmed by the finite-difference time-domain (FDTD) simulation results. We can also find that the Q-factors of the two PIT peaks have an opposite evolution tendency with the change of the stubs parameters and the maximum can reach to 427. These results may provide some applications for ultrasensitive sensors, switches and efficient filters. PMID:27075935

  18. Tunable high quality factor in two multimode plasmonic stubs waveguide

    PubMed Central

    Chen, Zhiquan; Li, Hongjian; Zhan, Shiping; Li, Boxun; He, Zhihui; Xu, Hui; Zheng, Mingfei

    2016-01-01

    We numerically investigate the optical characteristics of a metal-dielectric-metal (MDM) waveguide side-coupled with two identical multimode stub resonators. Double plasmon-induced transparency (PIT) peaks with narrow full width at half maximum (FWHM) and high quality factor (Q-factor) can be observed in this structure. The Q-factors of PIT peaks in two stub resonators system are larger than those in single stub resonator system. A multimode coupled-radiation oscillator theory (MC-ROT), which is derived from ROT, is proposed to analyze the spectral response in the multimode system for the first time. The analytical results are confirmed by the finite-difference time-domain (FDTD) simulation results. We can also find that the Q-factors of the two PIT peaks have an opposite evolution tendency with the change of the stubs parameters and the maximum can reach to 427. These results may provide some applications for ultrasensitive sensors, switches and efficient filters. PMID:27075935

  19. Tunable high quality factor in two multimode plasmonic stubs waveguide

    NASA Astrophysics Data System (ADS)

    Chen, Zhiquan; Li, Hongjian; Zhan, Shiping; Li, Boxun; He, Zhihui; Xu, Hui; Zheng, Mingfei

    2016-04-01

    We numerically investigate the optical characteristics of a metal-dielectric-metal (MDM) waveguide side-coupled with two identical multimode stub resonators. Double plasmon-induced transparency (PIT) peaks with narrow full width at half maximum (FWHM) and high quality factor (Q-factor) can be observed in this structure. The Q-factors of PIT peaks in two stub resonators system are larger than those in single stub resonator system. A multimode coupled-radiation oscillator theory (MC-ROT), which is derived from ROT, is proposed to analyze the spectral response in the multimode system for the first time. The analytical results are confirmed by the finite-difference time-domain (FDTD) simulation results. We can also find that the Q-factors of the two PIT peaks have an opposite evolution tendency with the change of the stubs parameters and the maximum can reach to 427. These results may provide some applications for ultrasensitive sensors, switches and efficient filters.

  20. Personnel neutron dosimetry at Department of Energy facilities

    SciTech Connect

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered.

  1. Optical Quality and Related Factors in Ocular Hypertension: Preliminary Study

    PubMed Central

    Wang, Yu-jing; Yang, Yan-ning; Huang, Lin-ying; Wang, Bo; Han, Yu-can; Yan, Jiang-bo

    2016-01-01

    Background. To evaluate the optical quality and related factors in patients with ocular hypertension (OHT). Methods. This was a prospective case-control study. A total of 12 eyes with OHT and 20 control eyes underwent testing with Optical Quality Analysis System II (OQAS II) to evaluate the modulation transfer function cut off frequency (MTF cutoff), the Strehl 2D ratio (SR), objective scatter index (OSI), tear-film mean OSI (TFOSI), and the OQAS values (OV100%,OV20%, and OV9%). Results. The optical quality of patients with OHT declined, with lower MTF cutoff (OHT 36.86 ± 7.11 cpd , controls 48.50 ± 4.04 cpd, t = −4.60, P < 0.05), lower SR (OHT 0.22 ± 0.04, controls 0.27 ± 0.05, t = −2.72, P < 0.05), lower OV100% (OHT 1.26 ± 0.25, controls 1.61 ± 0.14, t = −4.03, P < 0.05), lower OV20% (OHT 1.27 ± 0.27, controls 1.72 ± 0.20, t = −4.00, P < 0.05), and lower OV9% (OHT 1.30 ± 0.25, controls 1.69 ± 0.32, t = −2.28, P < 0.05). There were not any statistically significant differences in OSI and TFOSI. The MTF cutoff in patients with OHT was correlated significantly with age (r = −0.59, P < 0.05). Conclusions. Optical quality of patients with OHT is reduced, with lower MTF cutoff, SR, OV100%, OV20%, and OV9%. MTF cutoff is negatively related to age. PMID:27293874

  2. Neutron distribution, electric dipole polarizability and weak form factor of 48Ca from chiral effective field theory

    NASA Astrophysics Data System (ADS)

    Wendt, Kyle

    2016-03-01

    How large is the 48Ca nucleus? While the electric charge distribution of this nucleus was accurately measured decades ago, both experimental and ab initio descriptions of the neutron distribution are deficient. We address this question using ab initio calculations of the electric charge, neutron, and weak distributions of 48Ca based on chiral effective field theory. Historically, chiral effective field theory calculations of systems larger than 4 nucleons have been plagued by strong systematic errors which result in theoretical descriptions that are too dense and over bound. We address these errors using a novel approach that permits us to accurately reproduce binding energy and charge radius of 48Ca, and to constrain electroweak observables such as the neutron radius, electric dipole polarizability, and the weak form factor. For a full list of contributors to this work, please see ``Neutron and weak-charge distributions of the 48Ca nucleus,'' Nature Physics (2015) doi:10.1038/nphys3529.

  3. Uranium mass and neutron multiplication factor estimates from time-correlation coincidence counts

    NASA Astrophysics Data System (ADS)

    Xie, Wenxiong; Li, Jiansheng; Zhu, Jianyu

    2015-10-01

    Time-correlation coincidence counts of neutrons are an important means to measure attributes of nuclear material. The main deficiency in the analysis is that an attribute of an unknown component can only be assessed by comparing it with similar known components. There is a lack of a universal method of measurement suitable for the different attributes of the components. This paper presents a new method that uses universal relations to estimate the mass and neutron multiplication factor of any uranium component with known enrichment. Based on numerical simulations and analyses of 64 highly enriched uranium components with different thicknesses and average radii, the relations between mass, multiplication and coincidence spectral features have been obtained by linear regression analysis. To examine the validity of the method in estimating the mass of uranium components with different sizes, shapes, enrichment, and shielding, the features of time-correlation coincidence-count spectra for other objects with similar attributes are simulated. Most of the masses and multiplications for these objects could also be derived by the formulation. Experimental measurements of highly enriched uranium castings have also been used to verify the formulation. The results show that for a well-designed time-dependent coincidence-count measuring system of a uranium attribute, there are a set of relations dependent on the uranium enrichment by which the mass and multiplication of the measured uranium components of any shape and size can be estimated from the features of the source-detector coincidence-count spectrum.

  4. Examining the Factor Structure and Hierarchical Nature of the Quality of Life Construct

    ERIC Educational Resources Information Center

    Wang, Mian; Schalock, Robert L.; Verdugo, Miguel A.; Jenaro, Christina

    2010-01-01

    There is considerable debate in the area of individual quality of life research regarding the factor structure and hierarchical nature of the quality of life construct. Our purpose in this study was to test via structural equation modeling an a priori quality of life model consisting of eight first-order factors and one second-order factor. Data…

  5. His and Hers: Economic Factors and Relationship Quality in Germany

    PubMed Central

    Hardie, Jessica Halliday; Geist, Claudia; Lucas, Amy

    2014-01-01

    Research has linked economic factors to relationship quality in the United States, primarily using cross-sectional data. In the current study, 2 waves of the Panel Analysis of Intimate Relationships and Family Dynamics data (n = 2,937) were used to test the gendered association between economic factors and relationship satisfaction among young German couples. In contrast to U.S.-based studies, the findings showed striking gender differences in the association between economic factors and relationship satisfaction for Germans. In cross-sectional models, women’s relationship satisfaction was positively associated with receiving government economic support, and men’s satisfaction was positively associated with poverty status and negatively associated with being a breadwinner. Longitudinal models revealed that changes in poverty status are associated with women’s satisfaction, but men’s satisfaction remains tied to their role as family provider. These unexpected results suggest that men’s satisfaction is positively associated with a more equal division of labor market activity between partners. PMID:25045175

  6. g-Factors of Isomeric States in the Neutron-Rich Nuclei

    SciTech Connect

    Georgiev, G.; Neyens, G.; Hass, M.; Balabanski, Dimiter Loukanov; Bingham, Carrol R; Borcea, C.; Coulier, N.; Coussenment, R.; Daugas, J. M.; De France, Gilles M; Gorska, M.; Grawe, Hubert H; Grzywacz, Robert Kazimierz; Lewitowicz, Marek; Mach, Henryk A; Matea, I.; de Oliveira Santos, F.; Page, R. D.; Pfutzner, Marek; Penionzhkevich, Yu. E.; Podolyak, Zsolt F; Regan, Patrick H; Rykaczewski, Krzysztof Piotr; Sawicka, M.; Smirnova, N. A.; Sobolev, Yu.; Stanoiu, M.; Teughels, S.; Vyvey, K.

    2004-02-01

    We report the results from the first experiment to measure gyromagnetic factors of {micro}s isomers in neutron-rich nuclei produced by intermediate-energy projectile-fragmentation reactions. The Time Dependent Perturbed Angular Distribution (TDPAD) method was applied in combination with the heavy-ion-gamma correlation technique. The nuclides in the vicinity of {sup 68}Ni were produced and spin-oriented following the fragmentation of a {sup 76}Ge, 61.4 MeV/ u beam at GANIL. The results obtained, |g|({sup 69 m}Cu) = 0.225(25) and |g|({sup 67 m}Ni) = 0.125(6) provide another indication of the importance of proton excitation across the Z = 28 shell gap for the description of these states.

  7. Spallation Neutron Source Availability Top-Down Apportionment Using Characteristic Factors and Expert Opinion

    SciTech Connect

    Haire, M.J.; Schryver, J.C.

    1999-10-01

    Apportionment is the assignment of top-level requirements to lower tier elements of the overall facility. A method for apportioning overall facility availability requirements among systems and subsystems is presented. Characteristics that influence equipment reliability and maintainability are discussed. Experts, using engineering judgment, scored each characteristic for each system whose availability design goal is to be established. The Analytic Hierarchy Process (AHP) method is used to produce a set of weighted rankings for each characteristic for each alternative system. A mathematical model is derived which incorporates these weighting factors. The method imposes higher availability requirements on those systems in which an incremental increase in availability is easier to achieve, and lower availability requirements where greater availability is more difficult and costly. An example is given of applying this top-down apportionment methodology to the Spallation Neutron Source (SNS) facility.

  8. Multilevel factors affecting quality: examples from the cancer care continuum.

    PubMed

    Zapka, Jane; Taplin, Stephen H; Ganz, Patricia; Grunfeld, Eva; Sterba, Katherine

    2012-05-01

    The complex environmental context must be considered as we move forward to improve cancer care and, ultimately, patient and population outcomes. The cancer care continuum represents several care types, each of which includes multiple technical and communication steps and interfaces among patients, providers, and organizations. We use two case scenarios to 1) illustrate the variability, diversity, and interaction of factors from multiple levels that affect care quality and 2) discuss research implications and provide hypothetical examples of multilevel interventions. Each scenario includes a targeted literature review to illustrate contextual influences upon care and sets the stage for theory-informed interventions. The screening case highlights access issues in older women, and the survivorship case illustrates the multiple transition challenges faced by patients, families, and organizations. Example interventions show the potential gains of implementing intervention strategies that work synergistically at multiple levels. While research examining multilevel intervention is a priority, it presents numerous study design, measurement, and analytic challenges. PMID:22623591

  9. Estimation of quality factors by energy ratio method

    NASA Astrophysics Data System (ADS)

    Wang, Zong-Jun; Cao, Si-Yuan; Zhang, Hao-Ran; Qu, Ying-Ming; Yuan, Dian; Yang, Jin-Hao; Shao, Guan-Ming

    2015-03-01

    The quality factor Q, which reflects the energy attenuation of seismic waves in subsurface media, is a diagnostic tool for hydrocarbon detection and reservoir characterization. In this paper, we propose a new Q extraction method based on the energy ratio before and after the wavelet attenuation, named the energy-ratio method (ERM). The proposed method uses multipoint signal data in the time domain to estimate the wavelet energy without invoking the source wavelet spectrum, which is necessary in conventional Q extraction methods, and is applicable to any source wavelet spectrum; however, it requires high-precision seismic data. Forward zero-offset VSP modeling suggests that the ERM can be used for reliable Q inversion after nonintrinsic attenuation (geometric dispersion, reflection, and transmission loss) compensation. The application to real zero-offset VSP data shows that the Q values extracted by the ERM and spectral ratio methods are identical, which proves the reliability of the new method.

  10. Factors affecting quality of dried low-rank coals

    SciTech Connect

    Karthikeyan, M.; Kuma, J.V.M.; Hoe, C.S.; Ngo, D.L.Y.

    2007-07-01

    The chemical and physical properties of coal are strongly affected by the upgrading process employed. For high-moisture coals, upgrading involves thermal dehydration to improve the calorific value of the coal on mass basis. This study evaluates the feasibility of upgrading a low-rank/grade coal using the oven drying method. The objective of this research work is to study the drying characteristics of low-rank coals and to understand the factors affecting the quality of dried low-rank coals. This article describes laboratory experiments conducted on the characterization of the low-rank coals before and after the drying process. The results on drying kinetics, re-absorption of coal samples, and proximate analysis of coal samples before and after drying are discussed. It was found that the upgrading process produced coal with better heating value and combustion characteristics than those of the raw coal samples.

  11. Enhancing selectivity of infrared emitters through quality-factor matching

    NASA Astrophysics Data System (ADS)

    Sakr, Enas; Zhou, Zhiguang; Bermel, Peter

    2015-09-01

    It has recently been proposed that designing selective emitters with photonic crystals (PhCs) or plasmonic metamaterials can suppress low-energy photon emission, while enhancing higher-energy photon emission. Here, we will consider multiple approaches to designing and fabricating nanophotonic structures concentrating infrared thermal radiation at energies above a critical threshold. These are based on quality factor matching, in which one creates resonant cavities that couple light out at the same rate that the underlying materials emit it. When this quality-factor matching is done properly, emissivities can approach those of a blackbody, but only within a selected range of thermal photon energies. One potential application is for improving the conversion of heat to electricity via a thermophotovoltaic (TPV) system, by using thermal radiation to illuminate a photovoltaic (PV) diode. In this study, realistic simulations of system efficiencies are performed using finite-difference time domain (FDTD) and rigorous coupled wave analysis (RCWA) to capture both thermal radiation and PV diode absorption. We first consider a previously studied 2D molybdenum photonic crystal with a commercially-available silicon PV diode, which can yield TPV efficiencies up to 26.2%. Second, a 1D-periodic samarium-doped glass emitter with a gallium antimonide (GaSb) PV diode is presented, which can yield efficiencies up to 38.5%. Finally, a 2D tungsten photonic crystal with a 1D integrated, chirped filter and the GaSb PV diode can yield efficiencies up to 38.2%; however, the fabrication procedure is expected to be more challenging. The advantages and disadvantages of each strategy will be discussed.

  12. Transcription factor motif quality assessment requires systematic comparative analysis

    PubMed Central

    Kibet, Caleb Kipkurui; Machanick, Philip

    2016-01-01

    Transcription factor (TF) binding site prediction remains a challenge in gene regulatory research due to degeneracy and potential variability in binding sites in the genome. Dozens of algorithms designed to learn binding models (motifs) have generated many motifs available in research papers with a subset making it to databases like JASPAR, UniPROBE and Transfac. The presence of many versions of motifs from the various databases for a single TF and the lack of a standardized assessment technique makes it difficult for biologists to make an appropriate choice of binding model and for algorithm developers to benchmark, test and improve on their models. In this study, we review and evaluate the approaches in use, highlight differences and demonstrate the difficulty of defining a standardized motif assessment approach. We review scoring functions, motif length, test data and the type of performance metrics used in prior studies as some of the factors that influence the outcome of a motif assessment. We show that the scoring functions and statistics used in motif assessment influence ranking of motifs in a TF-specific manner. We also show that TF binding specificity can vary by source of genomic binding data. We also demonstrate that information content of a motif is not in isolation a measure of motif quality but is influenced by TF binding behaviour. We conclude that there is a need for an easy-to-use tool that presents all available evidence for a comparative analysis. PMID:27092243

  13. Determination and validation of prompt k0-factors with a monochromatic neutron beam at the Dhruva reactor

    NASA Astrophysics Data System (ADS)

    Nair, A. G. C.; Acharya, R.; Sudarshan, K.; Tripathi, R.; Reddy, A. V. R.; Goswami, A.

    2006-08-01

    Prompt Gamma-ray Neutron Activation Analysis (PGNAA) was carried out using a reflected neutron beam of 0.018 eV energy at the Dhruva research reactor, Bhabha Atomic Research Centre, Mumbai, India. The neutron beam characteristics, such as dimension, homogeneity and thermal equivalent flux were evaluated. The prompt k0-factors of about 15 elements were determined versus the 1951.1 keV gamma-ray of the 35Cl(n,γ) reaction. These prompt k0-factors are compared with the recommended k0-values for thermal neutrons and were found to be in good agreement, except for Gd, Cd and Hg. The internal mono-standard method was applied to analyze a meteorite and a stainless steel alloy (SS 316 M) using the recommended k0-values from the literature. As to the alloy, the measured concentrations were in good agreement with the nominal composition. For the meteorite sample, the concentrations of the major elements were in good agreement with the values determined using conventional neutron activation analysis.

  14. Coincidence gate utilization factors for neutron correlation counters with up to three components in the die-away profile

    SciTech Connect

    Croft, S.; McElroy, R.D.; Kane, S.C.

    2007-07-01

    We present analytical expressions for the gate utilization factors (GUFs), up to fourth order, for both signal triggered and random triggered histograms based on a three-component capture time profile. These are useful for refined design performance calculations of passive neutron multiplicity counters using shift register correlation analysis. To our knowledge, these expressions are new. (authors)

  15. Factors Influencing the Quality of Encapsulation in Rock Bolting

    NASA Astrophysics Data System (ADS)

    Aziz, Naj; Craig, Peter; Mirzaghorbanali, Ali; Nemcik, Jan

    2016-08-01

    Bolt installation quality is influenced by various factors, some are well known and others are less recognised. A programme of field and laboratory studies was undertaken to examine various factors of relevance to the load transfer mechanism between the bolt, resin and rock to ensure test methods truly represent field performance. Short encapsulation tests were undertaken as part of the Australian Coal Association Research Program (ACARP) funded project (C21011) with the ultimate aim of developing standard test methods for assessing bolt encapsulation with chemical resin anchor installations. The field study consisted of a series of Short Encapsulation Pull Tests (SEPT) carried out in three mines with different geological conditions to determine the most representative and practical method of SEPT. Additional field work included installation of bolts into threaded steel tubes for subsequent removal and laboratory evaluation. A series of pull tests was carried out by installing bolts in overhead rig mounted sandstone block, cast in concrete with controlled encapsulation length. Factors of importance considered included; borehole diameter, resin annulus thickness, installation time (including bolt spin to the back and "spin at back"), the effect of gloving and hole over drill. It was found that the borehole diameter had a detrimental effect on the encapsulation bonding strength. Bolt installation time of approximately 10 s constituted an acceptable time for effective bolt installation and within the resin manufacturers recommended time of 14 s. Maintaining constant length of encapsulation was paramount for obtaining consistency and repeatability of the test results. Finally, a numerical simulation study was carried out to assess the capabilities of FLAC 2D software in simulating the pull testing of rock bolts.

  16. Fabrication of silica ultra high quality factor microresonators.

    PubMed

    Maker, Ashley J; Armani, Andrea M

    2012-01-01

    Whispering gallery resonant cavities confine light in circular orbits at their periphery. The photon storage lifetime in the cavity, quantified by the quality factor (Q) of the cavity, can be in excess of 500ns for cavities with Q factors above 100 million. As a result of their low material losses, silica microcavities have demonstrated some of the longest photon lifetimes to date. Since a portion of the circulating light extends outside the resonator, these devices can also be used to probe the surroundings. This interaction has enabled numerous experiments in biology, such as single molecule biodetection and antibody-antigen kinetics, as well as discoveries in other fields, such as development of ultra-low-threshold microlasers, characterization of thin films, and cavity quantum electrodynamics studies.(3-7) The two primary silica resonant cavity geometries are the microsphere and the microtoroid. Both devices rely on a carbon dioxide laser reflow step to achieve their ultra-high-Q factors (Q>100 million). However, there are several notable differences between the two structures. Silica microspheres are free-standing, supported by a single optical fiber, whereas silica microtoroids can be fabricated on a silicon wafer in large arrays using a combination of lithography and etching steps. These differences influence which device is optimal for a given experiment. Here, we present detailed fabrication protocols for both types of resonant cavities. While the fabrication of microsphere resonant cavities is fairly straightforward, the fabrication of microtoroid resonant cavities requires additional specialized equipment and facilities (cleanroom). Therefore, this additional requirement may also influence which device is selected for a given experiment. PMID:22805153

  17. Quality assurance of temporal variability of natural decay chain and neutron induced background for low-level NORM analysis

    SciTech Connect

    Yoho, Michael; Porterfield, Donivan R.; Landsberger, Sheldon

    2015-09-22

    In this study, twenty-one high purity germanium (HPGe) background spectra were collected over 2 years at Los Alamos National Laboratory. A quality assurance methodology was developed to monitor spectral background levels from thermal and fast neutron flux levels and naturally occurring radioactive material decay series radionuclides. 238U decay products above 222Rn demonstrated minimal temporal variability beyond that expected from counting statistics. 238U and 232Th progeny below Rn gas displayed at most twice the expected variability. Further, an analysis of the 139 keV 74Ge(n, γ) and 691 keV 72Ge(n, n') spectral features demonstrated temporal stability for both thermal and fast neutron fluxes.

  18. Effects of extended storage on egg quality factors.

    PubMed

    Jones, D R; Musgrove, M T

    2005-11-01

    Eggs were collected from a single inline processing facility weekly for 3 wk (replicates). The eggs were stored at 4 degrees C and 80% RH. Sampling began the day after collection and continued each week for 10 wk. During analysis, 24 eggs were examined for egg weight, albumen height, Haugh units (HU), shell strength, and vitelline membrane strength for each replicate. Egg weight decreased (P < 0.0001) from approximately 61 to 57 g after 10 wk of storage. Eggs from the second replicate were significantly (P < 0.0001) heavier than the other replicates by an average of 3 g. On average, albumen height decreased with extended storage (P < 0.0001) from 7.05 to 4.85 mm. Albumen height was approximately 0.2 mm higher for the eggs in replicate 2 compared with the other replicates (P < 0.01). Haugh unit values decreased during cold storage from 82.59 to 67.43 (P < 0.0001). There were no differences between replicates for HU values. No differences were detected for shell strength between replicates or during extended storage. A significant difference (P < 0.05) was found in detectable vitelline membrane strength between replicates, but this difference was less than 0.05 g. The elasticity of the vitelline membrane decreased during storage (P < 0.01) remaining low after 6 wk. Extended cold storage led to decreases in egg weight, albumen height, and HU. However, average HU values were still within the range for grade A. Shell strength was not affected by extended storage. Vitelline membrane elasticity also decreased, which could lead to yolks more easily rupturing as consumers crack the eggs. The results indicated that although the physical quality factors monitored in this study decreased during storage, egg quality was still acceptable beyond current recommended shelf life guidelines. PMID:16463976

  19. A comparison of quality factors and weighting factors for characterizing astronaut radiation exposures

    NASA Technical Reports Server (NTRS)

    Zapp, Neal; Cucinotta, Frank; Atwell, W.

    2002-01-01

    Radiation exposures are typically characterized by two quantities. The first is the absorbed dose, or the energy deposited per unit mass for specific types of radiation passing through specified materials. The same amount of energy deposited in material by two different types of radiation, however, can result in two different levels of risk. Because of this, for the purpose of radiation protection operations, absorbed dose is modified by a second factor intended to normalize the risk associated with a given exposure. We present here an inter-comparison of methods for this modification. First is the radiation quality factor (Q), as defined by ICRP publication 60. This quantity is related functionally to the unrestricted linear energy transfer (LET) of a given radiation, and is multiplied by the absorbed dose to derive the dose equivalent (H). The second method for modifying absorbed dose is the radiation weighting factor, also given in ICRP-60, or as modified in NCRP report 115. To implement the weighting factor, the absorbed dose resulting from incidence of a particular radiation is multiplied by a factor assigned to that type of radiation, giving the equivalent dose. We compare calculations done based on identical fields of radiation representative of that encountered by the MIR space station, applying each of these two methods. c2002 COSPAR. Published by Elsevier Science Ltd. All rights reserved.

  20. Snacking patterns, diet quality, and cardiovascular risk factors in adults

    PubMed Central

    2014-01-01

    Background The relationship of snacking patterns on nutrient intake and cardiovascular risk factors (CVRF) in adults is unknown. The aim of this study was to examine the associations of snacking patterns with nutrient intake, diet quality, and a selection of CVRF in adults participating in the 2001-2008 National Health and Nutrition Examination Survey. Methods 24-hour dietary recalls were used to determine intake and cluster analysis was used to identify the snacking patterns. Height and weight were obtained and the health indices that were evaluated included diastolic and systolic blood pressure, high density lipoprotein-cholesterol, low density lipoprotein cholesterol, triacylglycerides, blood glucose, and insulin. Results The sample was participants (n = 18,988) 19+ years (50% males; 11% African-Americans; 72% white, 12% Hispanic-Americans, and 5% other). Cluster analyses generated 12 distinct snacking patterns, explaining 61% of the variance in snacking. Comparisons of snacking patterns were made to the no snack pattern. It was found that miscellaneous snacks constituted the most common snacking pattern (17%) followed by cakes/cookies/pastries (12%) and sweets (9%). Most snacking patterns were associated with higher energy intakes. Snacking patterns cakes/cookies/pastries, vegetables/legumes, crackers/salty snacks, other grains and whole fruit were associated with lower intakes of saturated fatty acids. Added sugars intakes were higher in the cakes/cookies/pastries, sweets, milk desserts, and soft drinks patterns. Five snack patterns (cakes/cookies/pastries, sweets, vegetable/legumes, milk desserts, soft drinks) were associated with lower sodium intakes. Several snack patterns were associated with higher intakes of potassium, calcium, fiber, vitamin A, and magnesium. Five snacking patterns (miscellaneous snacks; vegetables/legumes; crackers/salty snacks; other grains; and whole fruit) were associated with better diet quality scores. Alcohol was associated with

  1. Experimental validation of beam quality correction factors for proton beams

    NASA Astrophysics Data System (ADS)

    Gomà, Carles; Hofstetter-Boillat, Bénédicte; Safai, Sairos; Vörös, Sándor

    2015-04-01

    This paper presents a method to experimentally validate the beam quality correction factors (kQ) tabulated in IAEA TRS-398 for proton beams and to determine the kQ of non-tabulated ionization chambers (based on the already tabulated values). The method is based exclusively on ionometry and it consists in comparing the reading of two ionization chambers under the same reference conditions in a proton beam quality Q and a reference beam quality 60Co. This allows one to experimentally determine the ratio between the kQ of the two ionization chambers. In this work, 7 different ionization chamber models were irradiated under the IAEA TRS-398 reference conditions for 60Co beams and proton beams. For the latter, the reference conditions for both modulated beams (spread-out Bragg peak field) and monoenergetic beams (pseudo-monoenergetic field) were studied. For monoenergetic beams, it was found that the experimental kQ values obtained for plane-parallel chambers are consistent with the values tabulated in IAEA TRS-398; whereas the kQ values obtained for cylindrical chambers are not consistent—being higher than the tabulated values. These results support the suggestion (of previous publications) that the IAEA TRS-398 reference conditions for monoenergetic proton beams should be revised so that the effective point of measurement of cylindrical ionization chambers is taken into account when positioning the reference point of the chamber at the reference depth. For modulated proton beams, the tabulated kQ values of all the ionization chambers studied in this work were found to be consistent with each other—except for the IBA FC65-G, whose experimental kQ value was found to be 0.6% lower than the tabulated one. The kQ of the PTW Advanced Markus chamber, which is not tabulated in IAEA TRS-398, was found to be 0.997 ± 0.042 (k = 2), based on the tabulated value of the PTW Markus chamber.

  2. Clean measurements of the nucleon axial-vector and free-neutron magnetic form factors

    SciTech Connect

    Deur, Alexandre P.

    2013-11-01

    We discuss the feasibility of a weak charged current experiment using a low energy electron beam. A first goal is to measure the Q^2 dependence of the axial-vector form factor g_a(Q^2). It can be measured model-independently and as robustly as for electromagnetic form factors from typical electron scattering experiments, in contrast to the methods used so far to measure g_a(Q^2). If g_a(Q^2) follows a dipole form, the axial mass can be extracted with a better accuracy than the world data altogether. The most important detection equipment would be a segmented neutron detector with good momentum and angular resolution that is symmetric about the beam direction, and covers a moderate angular range. A high intensity beam (100 uA) is necessary. Beam polarization is highly desirable as it provides a clean measurement of the backgrounds. Beam energies between 70 and 110 MeV are ideal. This range would provide a Q^2 mapping of g_a between 0.01

  3. Clinical factors affecting quality of life of patients with asthma

    PubMed Central

    Uchmanowicz, Bartosz; Panaszek, Bernard; Uchmanowicz, Izabella; Rosińczuk, Joanna

    2016-01-01

    Background In recent years, there has been increased interest in the subjective quality of life (QoL) of patients with bronchial asthma. QoL is a significant indicator guiding the efforts of professionals caring for patients, especially chronically ill ones. The identification of factors affecting the QoL reported by patients, despite their existing condition, is important and useful to provide multidisciplinary care for these patients. Aim To investigate the clinical factors affecting asthma patients’ QoL. Methods The study comprised 100 patients (73 female, 27 male) aged 18–84 years (mean age was 45.7) treated in the Allergy Clinic of the Wroclaw Medical University Department and Clinic of Internal Diseases, Geriatrics and Allergology. All asthma patients meeting the inclusion criteria were invited to participate. Data on sociodemographic and clinical variables were collected. In this study, we used medical record analysis and two questionnaires: the Asthma Quality of Life Questionnaire (AQLQ) to assess the QoL of patients with asthma and the Asthma Control Test to measure asthma control. Results Active smokers were shown to have a significantly lower QoL in the “Symptoms” domain than nonsmokers (P=0.006). QoL was also demonstrated to decrease significantly as the frequency of asthma exacerbations increased (R=−0.231, P=0.022). QoL in the domain “Activity limitation” was shown to increase significantly along with the number of years of smoking (R=0.404; P=0.004). Time from onset and the dominant symptom of asthma significantly negatively affected QoL in the “Activity limitation” domain of the AQLQ (R=−0.316, P=0.001; P=0.029, respectively). QoL scores in the “Emotional function” and “Environmental stimuli” subscale of the AQLQ decreased significantly as time from onset increased (R=−0.200, P=0.046; R=−0.328, P=0.001, respectively). Conclusion Patients exhibiting better symptom control have higher QoL scores. Asthma patients’ Qo

  4. Benchmarking Potential Factors Leading to Education Quality: A Study of Cambodian Higher Education

    ERIC Educational Resources Information Center

    Chen, Ching-Yaw; Sok, Phyra; Sok, Keomony

    2007-01-01

    Purpose: To study the quality in higher education in Cambodia and explore the potential factors leading to quality in Cambodian higher education. Design/methodology/approach: Five main factors that were deemed relevant in providing quality in Cambodian higher education were proposed: academic curriculum and extra-curricular activities, teachers'…

  5. First Evaluation of the Biologic Effectiveness Factors of Boron Neutron Capture Therapy (BNCT) in a Human Colon Carcinoma Cell Line

    SciTech Connect

    Dagrosa, Maria Alejandra; Crivello, Martin; Perona, Marina; Thorp, Silvia; Santa Cruz, Gustavo Alberto; Pozzi, Emiliano; Casal, Mariana; Thomasz, Lisa; Cabrini, Romulo; Kahl, Steven; Juvenal, Guillermo Juan; Pisarev, Mario Alberto

    2011-01-01

    Purpose: DNA lesions produced by boron neutron capture therapy (BNCT) and those produced by gamma radiation in a colon carcinoma cell line were analyzed. We have also derived the relative biologic effectiveness factor (RBE) of the neutron beam of the RA-3- Argentine nuclear reactor, and the compound biologic effectiveness (CBE) values for p-boronophenylalanine ({sup 10}BPA) and for 2,4-bis ({alpha},{beta}-dihydroxyethyl)-deutero-porphyrin IX ({sup 10}BOPP). Methods and Materials: Exponentially growing human colon carcinoma cells (ARO81-1) were distributed into the following groups: (1) BPA (10 ppm {sup 10}B) + neutrons, (2) BOPP (10 ppm {sup 10}B) + neutrons, (3) neutrons alone, and (4) gamma rays ({sup 60}Co source at 1 Gy/min dose-rate). Different irradiation times were used to obtain total absorbed doses between 0.3 and 5 Gy ({+-}10%) (thermal neutrons flux = 7.5 10{sup 9} n/cm{sup 2} sec). Results: The frequency of micronucleated binucleated cells and the number of micronuclei per micronucleated binucleated cells showed a dose-dependent increase until approximately 2 Gy. The response to gamma rays was significantly lower than the response to the other treatments (p < 0.05). The irradiations with neutrons alone and neutrons + BOPP showed curves that did not differ significantly from, and showed less DNA damage than, irradiation with neutrons + BPA. A decrease in the surviving fraction measured by 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolium bromide (MTT) assay as a function of the absorbed dose was observed for all the treatments. The RBE and CBE factors calculated from cytokinesis block micronucleus (CBMN) and MTT assays were, respectively, the following: beam RBE: 4.4 {+-} 1.1 and 2.4 {+-} 0.6; CBE for BOPP: 8.0 {+-} 2.2 and 2.0 {+-} 1; CBE for BPA: 19.6 {+-} 3.7 and 3.5 {+-} 1.3. Conclusions: BNCT and gamma irradiations showed different genotoxic patterns. To our knowledge, these values represent the first experimental ones obtained for the RA-3 in a

  6. Tissue equivalent proportional counter neutron monitor

    SciTech Connect

    Smith, R.C.; Strode, J.N.

    1980-06-01

    The Tissue Equivalent Proportional Counter (TEPC) is a sensitive area monitoring instrument that can be used either in place at fixed locations or as a portable neutron exposure measuring device. The system monitors low levels of neutron radiation exposure and has the capability of accurately measuring neutron exposure rates as low as 0.1 mrem/hr. The computerized analysis system calculates the quality factor which is important for situations where the neutron to gamma ratio may vary significantly and irregularly such as in fuel fabrication or handling facilities.

  7. Precise Measurement of the Neutron Magnetic Form Factor G{sub M}{sup n} in the Few-GeV{sup 2} Region

    SciTech Connect

    Lachniet, J.; Afanasev, A.; Arenhoevel, H.; Brooks, W. K.; Gilfoyle, G. P.; Higinbotham, D.; Burkert, V. D.; Carman, D. S.; Cords, D.; Degtyarenko, P. V.; Deur, A.; Gyurjyan, V.; Ito, M. M.; Kageya, T.; Kubarovsky, V.; Lowry, M.; Manak, J. J.; Mecking, B. A.; Mestayer, M. D.; Niczyporuk, B. B.

    2009-05-15

    The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q{sup 2}=1.0-4.8 GeV{sup 2} with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.

  8. The gamma-ray and neutron shielding factors of fly-ash brick materials.

    PubMed

    Singh, Vishwanath P; Badiger, N M

    2014-03-01

    A comprehensive study of gamma-ray exposure build-up factors (EBFs) of fly-ash brick materials has been carried out for photon energies of 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path) by a geometrical progression (GP) fitting method. The EBF values of the fly-ash brick materials were found to be dependent upon the photon energy, penetration depth and chemical composition, and were found to be higher than the values for mud bricks and common bricks. Above a photon energy of 3 MeV for large penetration depths (>10 mfp), the EBF becomes directly proportional to Zeq. EBFs of fly-ashes were found to be less than or equal to those of concrete for low penetration depths (<10 mfp) for intermediate photon energies up to 1.5 MeV. The EBF values of fly-ash materials were found to be almost independent of Si concentration. The fast neutron removal cross sections of the fly-ash brick materials, mud bricks and common bricks were also calculated to understand their shielding effectiveness. The shielding effectiveness of the fly-ash materials against gamma-ray radiation was lower than that of common and mud bricks. PMID:24270465

  9. A simple parameterization for quality factor as a function of linear energy transfer

    NASA Technical Reports Server (NTRS)

    Townsend, Lawrence W.; Wilson, John; Cucinotta, Francis A.

    1987-01-01

    The paper presents a simple analytic approximation of the radiation quality factor (Q) as a function of linear energy transfer for use in radiation protection calculations. The paper also presents estimated quality factors in water for protons over a broad range of incident energies. It is shown that the quality factors are less than unity for all proton energies greater than 13 MeV.

  10. The Impact Factor: Implications of Open Access on Quality

    ERIC Educational Resources Information Center

    Grozanick, Sara E.

    2010-01-01

    There has been debate about the extent to which open access affects the quality of scholarly work. At the same time, researchers have begun to look for ways to evaluate the quality of open access publications. Dating back to the growth of citation indexes during the 1960s and 1970s, citation analysis--examining citation statistics--has since been…

  11. Factors Influencing Perceptions of Service Quality in Cooperative Extension Workers

    ERIC Educational Resources Information Center

    Anaza, Nwamaka A.; Rutherford, Brian N.; Widdows, Richard

    2012-01-01

    The authors examined the direct and indirect impact of empowerment on service quality as perceived by Extension staff. Using a sample 283 respondents, the results revealed that along with empowerment, constructs such as job satisfaction and organizational identification positively affected service quality. Undoubtedly, each of these variables…

  12. Validation of neutron flux redistribution factors in JSI TRIGA reactor due to control rod movements.

    PubMed

    Kaiba, Tanja; Žerovnik, Gašper; Jazbec, Anže; Štancar, Žiga; Barbot, Loïc; Fourmentel, Damien; Snoj, Luka

    2015-10-01

    For efficient utilization of research reactors, such as TRIGA Mark II reactor in Ljubljana, it is important to know neutron flux distribution in the reactor as accurately as possible. The focus of this study is on the neutron flux redistributions due to control rod movements. For analyzing neutron flux redistributions, Monte Carlo calculations of fission rate distributions with the JSI TRIGA reactor model at different control rod configurations have been performed. Sensitivity of the detector response due to control rod movement have been studied. Optimal radial and axial positions of the detector have been determined. Measurements of the axial neutron flux distribution using the CEA manufactured fission chambers have been performed. The experiments at different control rod positions were conducted and compared with the MCNP calculations for a fixed detector axial position. In the future, simultaneous on-line measurements with multiple fission chambers will be performed inside the reactor core for a more accurate on-line power monitoring system. PMID:26141293

  13. Quality of returns: Is it a factor in remanufacturing?

    NASA Astrophysics Data System (ADS)

    Behret, Hülya; Korugan, Aybek

    2005-11-01

    The return flow of remanufacturing processes is highly variable in terms of the quality of returned products. This fact causes higher variability in remanufacturing processing times. In order to decrease the variability in the process the returns can be inspected and classified according to their quality following their arrival. However this classification will add an extra cost to the remanufacturing process. In this study we investigate the pros and cons of such a classification.

  14. Analysis Supporting Factors and Constraints LPMP Performance in Improving the Quality of Education in Jambi Province

    ERIC Educational Resources Information Center

    Rosadi, Kemas Imron

    2015-01-01

    Development of education in Indonesia is based on three aspects, namely equity and expansion, quality and relevance, as well as good governance. Quality education is influenced by several factors related to quality education managerial leaders, limited funds, facilities, educational facilities, media, learning resources, tools and training…

  15. The human factors of quality and QA in R D environments

    SciTech Connect

    Hill, S.G.

    1990-01-01

    Achieving quality is a human activity. It is therefore important to consider the human in the design, development and evaluation of work processes and environments in an effort to enhance human performance and minimize error. It is also important to allow for individual differences when considering human factors issues. Human Factors is the field of study which can provide information on integrating the human into the system. Human factors and quality are related for the customer of R D work, R D personnel who perform the work, and the quality professional who overviews the process of quality in the work. 18 refs., 1 fig.

  16. The Use of a Multichannel Analyzer to Investigate Effects of Experimental Factors on Gross-Counting Gamma and Neutron Detectors

    SciTech Connect

    Volz, Heather M.; Rennie, John A.; Lovejoy, Christopher M.; Martinez, Diana E. R; Dempsey, Michael A.; Livesay, Jake; Lousteau, Angela

    2012-07-12

    Radiation detection technology is invaluable to many fields of study in identifying nuclear materials. However, many detectors use gross-counting methods that give only a relative count rate. Without a spectrum (information on counts over time vs energy), it can be more difficult to discern if an alarm is false, innocent, or real. In particular, we would like to understand better the effect of experimental factors (i.e., external conditions and equipment parameters) on detector data, with possible implications for false alarms. To more thoroughly characterize detector technology, a multichannel analyzer (MCA) was used to record spectra from neutron (helium-3 tubes) and gamma (photomultiplier tubes) gross-counting detectors. Several factors could affect the signal-to-noise ratio of sources. For example, we examined the effects of neutron detector high voltage setting on the appearance of a californium-252 spectrum, the effect of discriminator values on integrated counts in neutron detection, and the effect of gain changes on the gamma spectra from several sources. Possible implications of ambient temperature of the experiment on the data collected will be discussed. The input impedance of the MCA must be considered to ensure that data are not affected by the measurement itself. Moreover, a calibration on the MCA was performed to verify the conversion of a MCA channel number to a voltage. In summary, the series of source spectra collected on an MCA with a variety of experimental conditions allow us to understand factors that affect data better, and assure us that gross-counting neutron and gamma detectors will have minimal false alarms.

  17. [Correlations between wild Polygonatum odoratum quality and main ecological factors].

    PubMed

    Bu, Jing; Li, Deng-Wu; Wang, Dong-Mei

    2012-06-01

    By the methods of stepwise regression, principal component analysis, and grey relational grade analysis, this paper studied the correlations between the effective components (polysaccharides and water- and alcohol-soluble substances) contents and antioxidant activity of wild Polygonatum odoratum in different places and the ecological factors. Among the test ecological factors, the mean air temperature in January and in July, mean annual precipitation, frost-free period, and soil pH and total potassium were the main factors affecting the effective component contents of P. odoratum, with a contribution rate of 99.0%. As compared with soil factors, climatic factors made more contribution to the effective component contents. Soil total potassium was the key factor controlling the effective component contents, mean annual precipitation was the main decision factor, and mean air temperature in January was the main limiting factor. The plant polysaccharides and water-soluble substance contents were the key factors affecting the antioxidant activity of P. odoratum, and the capability of P. odoratum in excavating DPPH free radical increased with increasing contents of polysaccharides and water-soluble substances. PMID:22937629

  18. Advantage and limitations of weighting factors and weighted dose quantities and their units in boron neutron capture therapy.

    PubMed

    Rassow, J; Sauerwein, W; Wittig, A; Bourhis-Martin, E; Hideghéty, K; Moss, R

    2004-05-01

    ICRU/IAEA made proposals, which should be followed by all BNCT groups, to report always the four absorbed dose components, boron dose DB, proton dose Dp, gamma-ray dose Dgamma, and neutron dose Dn, as well as the sum DT of all components, as total absorbed dose, together with the total weighted dose Dw (to be used only for internal purposes, indicating the used weighting factors) at all points of interest and the treatment conditions. PMID:15191301

  19. Aspects of radiation beam quality and their effect on the dose response of polymer gels: Photons, electrons and fast neutrons

    NASA Astrophysics Data System (ADS)

    Berg, Andreas; Bayreder, Christian; Georg, Dietmar; Bankamp, Achim; Wolber, Gerd

    2009-05-01

    Polymer gels are generally assumed to exhibit no significant dependence of the dose response on the energy or type of irradiation for clinically used beam qualities. Based on reports on differences in dose response for low energy photons and particle beams with high linear energy transfer (LET) we here investigate the dose response and energy dependence for a normoxic methacrylic acid polymer gel (MAGAT) for X-rays (100 kV), high energy photon beams (E = 1.2 MeV (60Co), 6 MV and 15 MV) and for three different electron energies (4, 12 and 20 MeV). Due to the possible impact also the sensitivity of the dose response to the dose rate is reported. A reduction in polymer gel relaxation rate has been observed for proton and carbon beams due to the high Linear Energy Transfer (LET) of these types of radiations. We here report on the dose response of an acryl-amide polymer gel (PAG) in a fast neutron field along with collimation as proposed for Boron neutron capture therapy (BNCT).

  20. Charge form factor of the neutron at low momentum transfer from the 2H-->(e-->,e'n)1H reaction.

    PubMed

    Geis, E; Kohl, M; Ziskin, V; Akdogan, T; Arenhövel, H; Alarcon, R; Bertozzi, W; Booth, E; Botto, T; Calarco, J; Clasie, B; Crawford, C B; DeGrush, A; Donnelly, T W; Dow, K; Farkhondeh, M; Fatemi, R; Filoti, O; Franklin, W; Gao, H; Gilad, S; Hasell, D; Karpius, P; Kolster, H; Lee, T; Maschinot, A; Matthews, J; McIlhany, K; Meitanis, N; Milner, R G; Rapaport, J; Redwine, R P; Seely, J; Shinozaki, A; Sirca, S; Sindile, A; Six, E; Smith, T; Steadman, M; Tonguc, B; Tschalaer, C; Tsentalovich, E; Turchinetz, W; Xiao, Y; Xu, W; Zhang, C; Zhou, Z; Zwart, T

    2008-07-25

    We report new measurements of the neutron charge form factor at low momentum transfer using quasielastic electrodisintegration of the deuteron. Longitudinally polarized electrons at an energy of 850 MeV were scattered from an isotopically pure, highly polarized deuterium gas target. The scattered electrons and coincident neutrons were measured by the Bates Large Acceptance Spectrometer Toroid (BLAST) detector. The neutron form factor ratio GEn/GMn was extracted from the beam-target vector asymmetry AedV at four-momentum transfers Q2=0.14, 0.20, 0.29, and 0.42 (GeV/c)2. PMID:18764321

  1. Factors Affecting Quality Enhancement Procedures for E-Learning Courses

    ERIC Educational Resources Information Center

    Jara, Magdalena; Mellar, Harvey

    2009-01-01

    Purpose: This paper reports on an empirical study exploring the way in which campus-based higher education institutions (HEIs) in the UK apply their internal quality assurance and enhancement (QA/QE) procedures to their e-learning courses. The purpose of this paper is to identify those characteristics of e-learning courses which affected the…

  2. Do Non-Economic Quality of Life Factors Drive Immigration?

    ERIC Educational Resources Information Center

    Pacheco, Gail Anne; Rossouw, Stephanie; Lewer, Joshua

    2013-01-01

    This paper contributes to the immigration literature by generating two unique non-economic quality of life (QOL) indices and testing their role on recent migration patterns. Applying the generated QOL indices in conjunction with four independent welfare measures to an augmented gravity model of immigration, this paper finds an insignificant…

  3. Factors Influencing Assessment Quality in Higher Vocational Education

    ERIC Educational Resources Information Center

    Baartman, Liesbeth; Gulikers, Judith; Dijkstra, Asha

    2013-01-01

    The development of assessments that are fit to assess professional competence in higher vocational education requires a reconsideration of assessment methods, quality criteria and (self)evaluation. This article examines the self-evaluations of nine courses of a large higher vocational education institute. Per course, 4-11 teachers and 3-10…

  4. Current good manufacturing practices, quality control procedures, quality factors, notification requirements, and records and reports, for infant formula. Final rule.

    PubMed

    2014-06-10

    The Food and Drug Administration (FDA or we) is issuing a final rule that adopts, with some modifications, the interim final rule (IFR) entitled "Current Good Manufacturing Practices, Quality Control Procedures, Quality Factors, Notification Requirements, and Records and Reports, for Infant Formula'' (February 10, 2014). This final rule affirms the IFR's changes to FDA's regulations and provides additional modifications and clarifications. The final rule also responds to certain comments submitted in response to the request for comments in the IFR. PMID:24922980

  5. Quality assurance of temporal variability of natural decay chain and neutron induced background for low-level NORM analysis

    DOE PAGESBeta

    Yoho, Michael; Porterfield, Donivan R.; Landsberger, Sheldon

    2015-09-22

    In this study, twenty-one high purity germanium (HPGe) background spectra were collected over 2 years at Los Alamos National Laboratory. A quality assurance methodology was developed to monitor spectral background levels from thermal and fast neutron flux levels and naturally occurring radioactive material decay series radionuclides. 238U decay products above 222Rn demonstrated minimal temporal variability beyond that expected from counting statistics. 238U and 232Th progeny below Rn gas displayed at most twice the expected variability. Further, an analysis of the 139 keV 74Ge(n, γ) and 691 keV 72Ge(n, n') spectral features demonstrated temporal stability for both thermal and fast neutronmore » fluxes.« less

  6. Feedstock Quality Factor Calibration and Data Model Development

    SciTech Connect

    Richard D. Boardman; Tyler L. Westover; Garold L. Gresham

    2010-05-01

    The goal of the feedstock assembly operation is to deliver uniform, quality-assured feedstock materials that will enhance downstream system performance by avoiding problems in the conversion equipment. In order to achieve this goal, there is a need for rapid screening tools and methodologies for assessing the thermochemical quality characteristics of biomass feedstock through the assembly process. Laser-induced breakdown spectroscopy (LIBS) has been identified as potential technique that could allow rapid elemental analyses of the inorganic content of biomass feedstocks; and consequently, would complement the carbohydrate data provided by near-infrared spectrometry (NIRS). These constituents, including Si, K, Ca, Na, S, P, Cl, Mg, Fe and Al, create a number of downstream problems in thermochemical processes. In particular, they reduce the energy content of the feedstock, influence reaction pathways, contribute to fouling and corrosion within systems, poison catalysts, and impact waste streams.

  7. Factors influencing the surface quality of polished tool steels

    NASA Astrophysics Data System (ADS)

    Rebeggiani, S.; Rosén, B.-G.

    2014-09-01

    Today’s demands on surface quality of moulds for injection moulding of plastic components involve no/low defect contents and roughness levels in the nm-range for high gloss applications. Material properties as well as operating conditions influence the mould finish, and thus the final surface of moulded products. This paper focuses on how particle content and different polishing strategies influence final surface qualities of moulds. Visual estimations of polished tool steel samples were combined with non-contact 3D-surface texture analysis in order to correlate traditional assessments to more quantitative methods, and to be able to analyse the surfaces at nanometre-level. It was found that steels with a lower proportion of particles, like carbides and oxides, gave rise to smoother polished surfaces. In a comparative study of polishers from different polishing shops, it was found that while different surface preparation strategies can lead to similar final roughness, similar preparation techniques can produce high-quality surfaces from different steel grades. However, the non-contact 3D-surface texture analysis showed that not all smooth polished surfaces have desirable functional topographies for injection moulding of glossy plastic components.

  8. Analysis of psychological factors for quality assessment of interactive multimodal service

    NASA Astrophysics Data System (ADS)

    Yamagishi, Kazuhisa; Hayashi, Takanori

    2005-03-01

    We proposed a subjective quality assessment model for interactive multimodal services. First, psychological factors of an audiovisual communication service were extracted by using the semantic differential (SD) technique and factor analysis. Forty subjects participated in subjective tests and performed point-to-point conversational tasks on a PC-based TV phone that exhibits various network qualities. The subjects assessed those qualities on the basis of 25 pairs of adjectives. Two psychological factors, i.e., an aesthetic feeling and a feeling of activity, were extracted from the results. Then, quality impairment factors affecting these two psychological factors were analyzed. We found that the aesthetic feeling is mainly affected by IP packet loss and video coding bit rate, and the feeling of activity depends on delay time and video frame rate. We then proposed an opinion model derived from the relationships among quality impairment factors, psychological factors, and overall quality. The results indicated that the estimation error of the proposed model is almost equivalent to the statistical reliability of the subjective score. Finally, using the proposed model, we discuss guidelines for quality design of interactive audiovisual communication services.

  9. Improving the quality factor of cantilevers in viscous fluids by the adaptation of their interface

    NASA Astrophysics Data System (ADS)

    Linden, J.; Oesterschulze, E.

    2012-03-01

    The adaptation of the fluid-microresonator interface enables the operation of cantilevers with high quality factor in viscous fluids. Partial wetting was proposed to implement the adapted interface by meniscus formation. An excellent quality factor of 79 was achieved in water applying the concept of partial wetting to thin film silicon nitride cantilevers. Compared to the quality factor calculated from Sader's theory of the hydrodynamic damping of fully immersed cantilevers, this is an improvement by more than one decade. As a first application the partially wetted cantilevers were employed as mass sensors in water revealing a sensitivity of 2.77 fg/Hz.

  10. Pediatric Coccidioidomycosis Patients: Perceptions, Quality of Life and Psychosocial Factors

    PubMed Central

    Gaab, Erin Mary; Naeem, Fouzia

    2015-01-01

    Research investigating the effects of coccidioidomycosis (valley fever) on children and the psychosocial implications of this disease in general is lacking. This study reviews what is known about pediatric coccidioidomycosis patients. It documents the psychological functioning, quality of life, and illness perceptions of a sample of coccidioidomycosis patient families. Primary caregivers of pediatric patients and patients from a major hospital in the San Joaquin Valley of California were interviewed regarding their perceptions of disease detection, access to care and the patient/family experience. PMID:27417796

  11. Stream network expansion: a riparian water quality factor

    NASA Astrophysics Data System (ADS)

    Wigington, P. J., Jr.; Moser, T. J.; Lindeman, D. R.

    2005-05-01

    Little is known about how active stream network expansion during rainstorms influences the ability of riparian buffers to improve water quality. We used aerial photographs to quantify stream network expansion during the wet winter season in five agricultural catchments in western Oregon, USA. Winter stream drainage densities were nearly two orders of magnitude greater than summer stream densities, and agricultural land use was much more abundant along transient portions (e.g. swales, road ditches) of stream networks. Water moving from agricultural fields into expanded stream networks during large hydrologic events has the opportunity to bypass downstream riparian buffers along perennial streams and contribute nonpoint-source pollutants directly into perennial stream channels.

  12. Taking image quality factor into the OPC model tuning flow

    NASA Astrophysics Data System (ADS)

    Wang, Ching-Heng; Liu, Qingwei; Zhang, Liguo

    2007-03-01

    All OPC model builders are in search of a physically realistic model that is adequately calibrated and contains the information that can be used for process predictions and analysis of a given process. But there still are some unknown physics in the process and wafer data sets are not perfect. Most cases even using the average values of different empirical data sets will still take inaccurate measurements into the model fitting process, which makes the fitting process more time consuming and also may cause losing convergence and stability. The Image quality is one of the most worrisome obstacles faced by next-generation lithography. Nowadays, considerable effort is devoted to enhance the contrast, as well as understanding its impact on devices. It is a persistent problem for 193nm micro-lithography and will carry us for at least three generations, culminating with immersion lithography. This work is to weight different wafer data points with a weighting function. The weighting function is dependent on the Normal image log slope (NILS), which can reflect the image quality. Using this approach, we can filter wrong information of the process and make the OPC model more accurate. CalibreWorkbench is the platform we used in this study, which has been proven to have an excellent performance on 0.13um, 90nm and 65nm production and development models setup. Leveraging its automatic optical-tuning function, we practiced the best weighting approach to achieve the most efficient and convergent tuning flow.

  13. Associations between Pittsburgh Sleep Quality Index Factors and Health Outcomes in Women with Posttraumatic Stress Disorder

    PubMed Central

    Casement, Melynda D.; Harrington, Kelly M.; Miller, Mark W.; Resick, Patricia A.

    2012-01-01

    Objective The Pittsburgh Sleep Quality Index (PSQI) is a widely used measure of subjective sleep disturbance in clinical populations, including individuals with posttraumatic stress disorder (PTSD). Although the severity of sleep disturbance is generally represented by a global symptom score, recent factor analytic studies suggest that the PSQI is better characterized by a two- or three-factor model than a one-factor model. This study examined the replicability of two- and three-factor models of the PSQI, as well as the relationship between PSQI factors and health outcomes, in a female sample with PTSD. Methods The PSQI was administered to 319 women with PTSD related to sexual or physical assault. Confirmatory factor analyses tested the relative fit of one-, two-, and three-factor solutions. Bivariate correlations were performed to examine the shared variance between PSQI sleep factors and measures of PTSD, depression, anger, and physical symptoms. Results Confirmatory factor analyses supported a 3-factor model with Sleep Efficiency, Perceived Sleep Quality, and Daily Disturbances as separate indices of sleep quality. The severity of symptoms represented by the PSQI factors was positively associated with the severity of PTSD, depression, and physical symptoms. However, these health outcomes correlated as much or more with the global PSQI score as with PSQI factor scores. Conclusions These results support the multidimensional structure of the PSQI. Yet, the global PSQI score has as much or more explanatory power as individual PSQI factors in predicting health outcomes. PMID:22542787

  14. Winter wheat quality monitoring and forecasting system based on remote sensing and environmental factors

    NASA Astrophysics Data System (ADS)

    Haiyang, Yu; Yanmei, Liu; Guijun, Yang; Xiaodong, Yang; Dong, Ren; Chenwei, Nie

    2014-03-01

    To achieve dynamic winter wheat quality monitoring and forecasting in larger scale regions, the objective of this study was to design and develop a winter wheat quality monitoring and forecasting system by using a remote sensing index and environmental factors. The winter wheat quality trend was forecasted before the harvest and quality was monitored after the harvest, respectively. The traditional quality-vegetation index from remote sensing monitoring and forecasting models were improved. Combining with latitude information, the vegetation index was used to estimate agronomy parameters which were related with winter wheat quality in the early stages for forecasting the quality trend. A combination of rainfall in May, temperature in May, illumination at later May, the soil available nitrogen content and other environmental factors established the quality monitoring model. Compared with a simple quality-vegetation index, the remote sensing monitoring and forecasting model used in this system get greatly improved accuracy. Winter wheat quality was monitored and forecasted based on the above models, and this system was completed based on WebGIS technology. Finally, in 2010 the operation process of winter wheat quality monitoring system was presented in Beijing, the monitoring and forecasting results was outputted as thematic maps.

  15. Characteristics of double-plasmonic-racetrack resonator to increase quality factor

    NASA Astrophysics Data System (ADS)

    Okamoto, Hiroyuki; Onishi, Sei; Kataoka, Mai; Yamaguchi, Kenzo; Haraguchi, Masanobu; Okamoto, Toshihiro

    2013-01-01

    We have numerically evaluated wavelength characteristics at telecommunication wavelengths by means of a doubleplasmonic-racetrack resonator using the finite-difference time domain method. We investigated the effect of the space between the two plasmonic racetracks of the resonator on the quality factor. The quality factor of the proposed structure is 57 when the space between two racetracks is 600 nm. The quality factor of a double-plasmonic-racetrack resonator of a dielectric-filled trench is 1.5 times greater than that of a single-plasmonic-racetrack resonator of an air-filled trench. The phase mismatch of the trench channel plasmon polaritons contributes to the quality factor of the double-plasmonicracetrack resonator.

  16. Investigating the frequency spectrum of mechanical quality factor for piezoelectric materials based on phenomenological model

    NASA Astrophysics Data System (ADS)

    Shi, Weijia; Zhao, Hui; Ma, Jie; Yao, Yu; Uchino, Kenji

    2015-10-01

    Heat generation due to losses restricts piezoelectric materials from maintaining a high power density, which will further limit the miniaturization of piezoelectric devices. As an evaluation index of the loss level, the mechanical quality factor shows an opposite tendency with losses. The mechanical quality factor should therefore be evaluated. By new methods to determine the mechanical quality factor, the highest mechanical quality factor has been discovered within the working bandwidth other than the resonance and antiresonance frequencies, which is almost double the value at the resonance. In this study, the prime determinant of the maximum value has been experimentally investigated on the basis of the phenomenological model of the admittance phase. The investigation experimentally infers that the change in the tendency of the phase leads to the appearance of the maximum value. Thus, the new phenomenon is experimentally explained for the first time.

  17. Assessment of the neutron emission anisotropy factor of a sealed AmBe source by means of measurements and Monte Carlo simulations

    NASA Astrophysics Data System (ADS)

    Loreti, S.; Pietropaolo, A.

    2015-10-01

    The neutron emission anisotropy factor of a sealed Americium-Beryllium source is experimentally determined and compared to Monte Carlo simulations. The measurements were done at the Italian Institute for Metrology of Ionizing Radiations using a long counter neutron detector and a "X.3" type AmBe sealed neutron source. Experimental data are compared to simulations performed with the MCNP code where the precise structure of the source is taken into account starting from its technical design. The contributions of the single structural parts are described to point out the effective sources of the emission anisotropy.

  18. Change in Quality of Life after Rehabilitation: Prognostic Factors for Visually Impaired Adults

    ERIC Educational Resources Information Center

    Langelaan, Maaike; de Boer, Michiel R.; van Nispen, Ruth M. A.; Wouters, Bill; Moll, Annette C.; van Rens, Ger H. M. B.

    2009-01-01

    The overall aim of rehabilitation for visually impaired adults is to improve the quality of life and (societal) participation. The objectives of this study were to obtain the short-term and long-term outcome of a comprehensive rehabilitation programme on quality of life for visually impaired adults, and prognostic baseline factors responsible for…

  19. Factors Associated with the Utilization and Quality of Prenatal Care in Western Rural Regions of China

    ERIC Educational Resources Information Center

    Dongxu, Wang; Yuhui, Shi; Stewart, Donald; Chun, Chang; Chaoyang, Li

    2012-01-01

    Purpose: The paper seeks to identify key features of prenatal care utilization and quality in western regions of China and to determine the factors affecting the quality of prenatal care. Design/methodology/approach: A descriptive, cross-sectional study was conducted. The instrument for the study was a 10-stem respondent-administered, structured…

  20. Diet quality is inversely related to cardiovascular risk factors in adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The goal of the study was to determine if there was an association between diet quality and cardiovascular risk factors in adults. National Health and Nutrition Examination Survey 2001–2008 data were used to compare diet quality, as determined by using 2005 Healthy Eating Index-2005 scores, and card...

  1. On the potential impact of the newly proposed quality factors on space radiation protection

    NASA Technical Reports Server (NTRS)

    Wilson, John W.; Townsend, Lawrence W.; Cucinotta, Francis A.

    1987-01-01

    The recently proposed changes in the defined quality factor hold great potential for easing some of the protection requirements from electrons and protons in the near-Earth environment. At the same time, the high Linear Energy Transfer (LET) components play an even more important role which must be further evaluated. Several recommendations are made which need to be addressed before these new quality factors can be implemented into space radiation potection practice.

  2. Measurements of the electric form factor of the neutron at JLab via recoil polarimetry in the reaction: d(e, e-prime n)p

    SciTech Connect

    J.M. Finn

    2004-11-01

    Preliminary results are reported for measurements of the ratio of the electric form factor to the magnetic form factor of the neutron, GEn/GMn, obtained via recoil polarimetry from the quasielastic 2H(e, e?n) 1H reaction at Q2 values of 0.45, 1.13, and 1.45 (GeV/c)2. The measurements, conducted in Hall C of the Thomas Jefferson National Accelerator Facility, together with other recent polarization measurements, are the result of a decade long effort to establish a firm experimental database for the important, but elusive, electric form factor of the neutron.

  3. A Secreted Factor Coordinates Environmental Quality with Bacillus Development

    PubMed Central

    Ababneh, Qutaiba O.; Tindall, Amanda J.; Herman, Jennifer K.

    2015-01-01

    Entry into sporulation is governed by the master regulator Spo0A. Spo0A accumulates in its active form, Spo0A-P, as cells enter stationary phase. Prior reports have shown that the acute induction of constitutively active Spo0A during exponential growth does not result in sporulation. However, a subsequent study also found that a gradual increase in Spo0A-P, mediated through artificial expression of the kinase, KinA, during exponential growth, is sufficient to trigger sporulation. We report here that sporulation via KinA induction depends on the presence of an extracellular factor or factors (FacX) that only accumulates to active levels during post-exponential growth. FacX is retained by dialysis with a cutoff smaller than 500 Dalton, can be concentrated, and is susceptible to proteinase K digestion, similar to described quorum-sensing peptides shown to be involved in promoting sporulation. However, unlike previously characterized peptides, FacX activity does not require the Opp or App oligopeptide transporter systems. In addition, FacX activity does not depend on SigH, Spo0A, or ComX. Importantly, we find that in the presence of FacX, B. subtilis can be induced to sporulate following the artificial induction of constitutively active Spo0A. These results indicate that there is no formal requirement for gradual Spo0A-P accumulation and instead support the idea that sporulation requires both sufficient levels of active Spo0A and at least one other signal or condition. PMID:26657919

  4. Microdosimetry of fast neutrons in selected biological materials

    SciTech Connect

    Wallace, R.E.

    1987-01-01

    Microdosimetric quantities for selected neutron beams have been determined in muscle, brain, bone, and fat tissue equivalent materials. The quantities of interest were the dose distribution in lineal energy, frequency average lineal energy, dose average lineal energy, and dose average quality factor. A dose response factor was defined to combine the lineal energy dose spectrum with a response function per unit KERMA for an acute biological endpoint in prototype cells in vitro. The dependence of each quantity on material composition and neutron energy was investigated by theoretical calculation and separated into primary and scatter neutron fluence components. Neutron fluences in phantoms were calculated using a standard Monte Carlo code (MCNP). The charged particle fluences and lineal energy dose spectra were obtained using the continuous slowing-down approximation. Calculated microdosimetric spectra agreed with those measured in muscle-equivalent materials. The microdosimetry of primary and scattered neutrons in a large tissue phantom was calculated for three representative uncollimated neutron sources.

  5. A systematic review and analysis of factors associated with methodological quality in laparoscopic randomized controlled trials.

    PubMed

    Antoniou, Stavros Athanasios; Andreou, Alexandros; Antoniou, George Athanasios; Bertsias, Antonios; Köhler, Gernot; Koch, Oliver Owen; Pointner, Rudolph; Granderath, Frank-Alexander

    2015-01-01

    Several methods for assessment of methodological quality in randomized controlled trials (RCTs) have been developed during the past few years. Factors associated with quality in laparoscopic surgery have not been defined till date. The aim of this study was to investigate the relationship between bibliometric and the methodological quality of laparoscopic RCTs. The PubMed search engine was queried to identify RCTs on minimally invasive surgery published in 2012 in the 10 highest impact factor surgery journals and the 5 highest impact factor laparoscopic journals. Eligible studies were blindly assessed by two independent investigators using the Scottish Intercollegiate Guidelines Network (SIGN) tool for RCTs. Univariate and multivariate analyses were performed to identify potential associations with methodological quality. A total of 114 relevant RCTs were identified. More than half of the trials were of high or acceptable quality. Half of the reports provided information on comparative demo graphic data and only 21% performed intention-to-treat analysis. RCTs with sample size of at least 60 patients presented higher methodological quality (p = 0.025). Upon multiple regression, reporting on preoperative care and the experience level of surgeons were independent factors of quality. PMID:25896540

  6. Factors controlling air quality in different European subway systems.

    PubMed

    Martins, Vânia; Moreno, Teresa; Mendes, Luís; Eleftheriadis, Konstantinos; Diapouli, Evangelia; Alves, Célia A; Duarte, Márcio; de Miguel, Eladio; Capdevila, Marta; Querol, Xavier; Minguillón, María Cruz

    2016-04-01

    Sampling campaigns using the same equipment and methodology were conducted to assess and compare the air quality at three South European subway systems (Barcelona, Athens and Oporto), focusing on concentrations and chemical composition of PM2.5 on subway platforms, as well as PM2.5 concentrations inside trains. Experimental results showed that the mean PM2.5 concentrations widely varied among the European subway systems, and even among different platforms within the same underground system, which might be associated to distinct station and tunnel designs and ventilation systems. In all cases PM2.5 concentrations on the platforms were higher than those in the urban ambient air, evidencing that there is generation of PM2.5 associated with the subway systems operation. Subway PM2.5 consisted of elemental iron, total carbon, crustal matter, secondary inorganic compounds, insoluble sulphate, halite and trace elements. Of all metals, Fe was the most abundant, accounting for 29-43% of the total PM2.5 mass (41-61% if Fe2O3 is considered), indicating the existence of an Fe source in the subway system, which could have its origin in mechanical friction and wear processes between rails, wheels and brakes. The trace elements with the highest enrichment in the subway PM2.5 were Ba, Cu, Mn, Zn, Cr, Sb, Sr, Ni, Sn, Co, Zr and Mo. Similar PM2.5 diurnal trends were observed on platforms from different subway systems, with higher concentrations during subway operating hours than during the transport service interruption, and lower levels on weekends than on weekdays. PM2.5 concentrations depended largely on the operation and frequency of the trains and the ventilation system, and were lower inside the trains, when air conditioning system was operating properly, than on the platforms. However, the PM2.5 concentrations increased considerably when the train windows were open. The PM2.5 levels inside the trains decreased with the trains passage in aboveground sections. PMID:26717078

  7. Risk factors and monitoring for water quality to determine best management practices for splash parks.

    PubMed

    de Man, H; Leenen, E J T M; van Knapen, F; de Roda Husman, A M

    2014-09-01

    Splash parks have been associated with infectious disease outbreaks as a result of exposure to poor water quality. To be able to protect public health, risk factors were identified that determine poor water quality. Samples were taken at seven splash parks where operators were willing to participate in the study. Higher concentrations of Escherichia coli were measured in water of splash parks filled with rainwater or surface water as compared with sites filled with tap water, independent of routine inspection intervals and employed disinfection. Management practices to prevent fecal contamination and guarantee maintaining good water quality at splash parks should include selection of source water of acceptable quality. PMID:25252342

  8. No-reference remote sensing image quality assessment using a comprehensive evaluation factor

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Wang, Xu; Li, Xiao; Shao, Xiaopeng

    2014-05-01

    The conventional image quality assessment algorithm, such as Peak Signal to Noise Ratio (PSNR), Mean Square Error(MSE) and structural similarity (SSIM), needs the original image as a reference. It's not applicable to the remote sensing image for which the original image cannot be assumed to be available. In this paper, a No-reference Image Quality Assessment (NRIQA) algorithm is presented to evaluate the quality of remote sensing image. Since blur and noise (including the stripe noise) are the common distortion factors affecting remote sensing image quality, a comprehensive evaluation factor is modeled to assess the blur and noise by analyzing the image visual properties for different incentives combined with SSIM based on human visual system (HVS), and also to assess the stripe noise by using Phase Congruency (PC). The experiment results show this algorithm is an accurate and reliable method for Remote Sensing Image Quality Assessment.

  9. Nanotube mechanical resonators with quality factors of up to 5 million.

    PubMed

    Moser, J; Eichler, A; Güttinger, J; Dykman, M I; Bachtold, A

    2014-12-01

    Carbon nanotube mechanical resonators have attracted considerable interest because of their small mass, the high quality of their surfaces, and the pristine electronic states they host. However, their small dimensions result in fragile vibrational states that are difficult to measure. Here, we observe quality factors Q as high as 5 × 10(6) in ultra-clean nanotube resonators at a cryostat temperature of 30 mK, where we define Q as the ratio of the resonant frequency over the linewidth. Measuring such high quality factors requires the use of an ultra-low-noise method to rapidly detect minuscule vibrations, as well as careful reduction of the noise of the electrostatic environment. We observe that the measured quality factors fluctuate because of fluctuations of the resonant frequency. We measure record-high quality factors, which are comparable to the highest Q values reported in mechanical resonators of much larger size, a remarkable result considering that reducing the size of resonators is usually concomitant with decreasing quality factors. The combination of ultra-low mass and very large Q offers new opportunities for ultra-sensitive detection schemes and quantum optomechanical experiments. PMID:25344688

  10. Personal and contextual factors predicting patients' reported quality of life: exploring congruency with Betty Neuman's assumptions.

    PubMed

    Hinds, C

    1990-04-01

    The search for factors which influence seriously ill people's quality of life continues to generate both interest and research. A retrospective cross-sectional study was conducted among 87 patients with lung cancer who ranged between the ages of 38 and 82 years. The purposes of this investigation were to determine whether relationships existed between patients' preferences for illness-related information, their satisfaction with family functioning, their level of learned resourcefulness and their reported quality of life. This paper focuses on the results of a stepwise multiple regression analysis which identified seven factors, namely, prognosis, surgery, current radiotherapy, performance status, self-control skills (learned resourcefulness), preference for information and age-group, which accounted for 30% of explained variance in patients' reported quality of life. No single factor contributed a substantial amount of the variance in this sample's reported quality of life. This observation suggests differences in people's perceptions of these factors and their importance to them. These results support a conclusion that people's evaluation of their quality of life is subjective, changeable and depends on the circumstances they face. Congruence between the assumptions underlying Neuman's health care system model, and the personal and contextual nature of these seven factors in patients' quality of life are explored. These findings are relevant for practice. PMID:2341691

  11. Not So Fast: Inflation in Impact Factors Contributes to Apparent Improvements in Journal Quality

    ERIC Educational Resources Information Center

    Neff, Bryan D.; Olden, Julian D.

    2010-01-01

    The Institute for Scientific Information (ISI) impact factor has become an important standard for assessing journal quality. Here we propose that impact factors may be subject to inflation analogous to changes in monetary prices in economics. The possibility of inflation came to light as a result of the observation that papers published today tend…

  12. Factors Affecting Perceived Learning, Satisfaction, and Quality in the Online MBA: A Structural Equation Modeling Approach

    ERIC Educational Resources Information Center

    Sebastianelli, Rose; Swift, Caroline; Tamimi, Nabil

    2015-01-01

    The authors examined how six factors related to content and interaction affect students' perceptions of learning, satisfaction, and quality in online master of business administration (MBA) courses. They developed three scale items to measure each factor. Using survey data from MBA students at a private university, the authors estimated structural…

  13. Complex seismic amplitude inversion for P-wave and S-wave quality factors

    NASA Astrophysics Data System (ADS)

    Zong, Zhaoyun; Yin, Xingyao; Wu, Guochen

    2015-07-01

    Stratum quality factors (P-wave and S-wave quality factors, Qp and Qs) have gradually been utilized in the study of physical state of crust and uppermost mantle, tectonic evolution, hydrogeololgy, gas hydrates, petroleum exploration, etc. Different opinions of the seismic attenuation mechanism result in various approaches to estimate the P-wave and S-wave quality factors. Considering the viscoelasticity of the underground medium, the constitutive matrix of the Earth medium is written as the superposition of homogeneous background medium, elastic perturbation medium and viscoelastic perturbation medium. Under the hypothesis of Born integral and stationary phase approximation, the seismic reflectivity is initially raised in terms of P-wave and S-wave moduli, density, P-wave and S-wave quality factors. Furthermore, incorporating the complex seismic traces with the seismic wavelets at different offsets, a two-step inversion approach is proposed to estimate the P-wave and S-wave quality factors. The AVO/AVA Bayesian inversion approach is suggested to estimate the P-wave modulus and S-wave modulus with the real component of the pre-stack seismic data initially. Taking the estimated P-wave and S-wave moduli as prior information, the P-wave and S-wave quality factors are further estimated with the imaginary component of the complex pre-stack seismic data, which is the quadrature of the original data. Finally, synthetic examples demonstrate that the proposed approach is able to estimate P-wave and S-wave quality factors stably and properly, and two field data examples demonstrate that the proposed approach may work as an efficient approach to fluid identification.

  14. Operator role definition: An initial step in the human factors engineering design of the advanced neutron source (ANS)

    SciTech Connect

    Knee, H.E.; Spelt, P.F.; Houser, M.M.; Hill, W.E.

    1994-12-31

    The Advanced Neutron Source (ANS) is a new basic and applied research facility sponsored by the U.S. Department of Energy that is proposed for construction. It will provide neutron beams for measurements and experiments in the fields of materials science and engineering, biology, chemistry, materials analysis, and nuclear science. The facility will provide a useful neutron beam flux that is at least five times more than is available at the world`s best existing facilities. It will also provide world-class facilities for isotopes production, materials irradiation testing, materials analysis, and the production of positrons. ANS will be unique in the United States in the extent to which human factors engineering (HFE) principles will be included in its design and construction. Initial HFE accomplishments include the development of a functional analysis, an operating philosophy, and a program plan. In fiscal year 1994, HFE activities are focusing on the role of the ANS control room reactor operator (RO). An operator-centered control room model was used in conjunction with information gathered from existing ANS system design descriptions and other literature to define RO responsibilities. From this list, a survey instrument was developed and administered to ANS design engineers, operations management personnel at Oak Ridge National Laboratory`s High Flux Isotope Reactor (HFIR), and HFIR ROs to detail the nature of the RO position. Initial results indicated that the RO should function as a high-level system supervisor with considerable monitoring, verification, and communication responsibilities. The relatively high level of control automation has resulted in a reshaping of the RO`s traditional safety and investment protection roles.

  15. Factors that Influence Quality of Life in Rural Children with Asthma and their Parents

    PubMed Central

    Walker, Jennifer; Winkelstein, Marilyn; Land, Cassia; Lewis-Boyer, Lapricia; Quartey, Ruth; Pham, Luu; Butz, Arlene

    2008-01-01

    Introduction Among rural children with asthma and their parents, this study examined the relationship between parental and child reports of quality of life and described the relationship of several factors such as asthma severity, missed days of work and asthma education on their quality of life. Method Two hundred and one rural families with asthma were enrolled in a school-based educational program. Intervention parents and children received interactive asthma workshop(s), asthma devices and literature. Parent and child quality of life measurements were obtained pre and post intervention using Juniper's Paediatric Caregivers Quality of Life and Juniper's Paediatric Quality of Life Questionnaires. Asthma severity was measured using criteria from the National Asthma Education and Prevention Program (NAEPP) guidelines. Results There was no association between parent and child total quality of life scores, and mean parental total quality of life scores were higher at baseline and follow-up than those of the children. All the parents' quality of life scores were correlated with parental reports of missed days of work. For all children, emotional quality of life (EQOL) was significantly associated with parental reports of school days missed (p= .03) and marginally associated with parental reports of hospitalizations due to asthma (p=.0.08). Parent's emotional quality of life (EQOL) and activity quality of life (AQOL) were significantly associated with children's asthma severity (EQOL, p=.009, AQOL, p=0.03), but not the asthma educational intervention. None of the child quality of life measurements were associated with asthma severity. Discussion Asthma interventions for rural families should help families focus on gaining and maintaining low asthma severity levels in order for families to enjoy an optimal quality of life. Health care providers should try to assess the child's quality of life at each asthma care visit independently of the parents. PMID:18971080

  16. A summary of ammonia emission factors and quality criteria for commercial poultry production in North America

    NASA Astrophysics Data System (ADS)

    Wood, David; Cowherd, Savannah; Van Heyst, Bill

    2015-08-01

    Efforts to quantify emissions of ammonia to the atmosphere from poultry housing in North America have been underway for the past two decades. In order to accurately estimate emissions from facilities in each poultry sector, emission factors used to derive the average must be of sufficiently high quality. However, it has become evident that current methods are inadequate and emission factors do not accurately reflect North American poultry production. Using an initial screening, based on measurement methods for ammonia and ventilation rates as well as study duration, a collection of studies have been identified that report the highest quality emission factors currently available. Each study was rated for data quality and then an average emission factor was developed for each sector of poultry production and rated based its ability to represent that sector. The laying hen sector, using deep pit manure storage, received a C (average) emission factor quality rating, which is the highest of all the poultry sectors evaluated. Laying hen with manure belts, broiler chicken, and turkey sectors received quality ratings considered to be below average or poor. This study highlights the need for additional research that needs to be conducted in order to accurately quantify ammonia releases from housing in most poultry sectors in North America.

  17. Influence of the dielectric background on the quality factors of metallo-dielectric photonic crystals

    NASA Astrophysics Data System (ADS)

    Ustyantsev, M. A.; Marsal, L. F.; Ferré-Borrull, J.; Pallarès, J.

    2007-06-01

    The effect of varying the dielectric background on the quality factor of two-dimensional metallo-dielectric photonic crystals is theoretically studied. The studied metallo-dielectric photonic crystal consists of a square lattice of circular metallic rods embedded into a dielectric background with a defect rod on the center that creates resonant modes within the photonic band gap. The metal is modeled with the Drude dispersion relation. A combination of the finite-difference time-domain method together with a frequency filtering technique is used to estimate accurately the resonant frequencies and their quality factors. The results show that the quality factors increase with increasing background dielectric constant. If a dielectric background material such as Silicon is used instead of air, an enhancement in the quality factor of up to eight times can be achieved, depending on the resonant mode. We also show that, depending on the modes, there exists an optimal size for the defect rod that gives the maximum quality factor.

  18. Study on γ-ray exposure buildup factors and fast neutron-shielding properties of some building materials

    NASA Astrophysics Data System (ADS)

    Singh, Vishwanath P.; Badiger, N. M.; El-Khayatt, A. M.

    2014-06-01

    We have computed γ-ray exposure buildup factors (EBF) of some building materials; glass, marble, flyash, cement, limestone, brick, plaster of paris (POP) and gypsum for energy 0.015-15 MeV up to 40 mfp (mfp, mean free path) penetration depth. Also, the macroscopic effective removal cross-sections (ΣR) for fast neutron were calculated. We discussed the dependency of EBF values on photon energy, penetration depth and chemical elements. The half-value layer and kinetic energy per unit mass relative to air of building materials were calculated for assessment of shielding effectiveness. Shielding thicknesses for glass, marble, flyash, cement, limestone and gypsum plaster (or Plaster of Paris, POP) were found comparable with ordinary concrete. Among the studied materials limestone and POP showed superior shielding properties for γ-ray and neutron, respectively. Radiation safety inside houses, schools and primary health centers for sheltering and annual dose can be assessed by the determination of shielding parameters of common building materials.

  19. Neutron effects in humans: protection considerations

    SciTech Connect

    Fry, R.J.M.

    1985-01-01

    Committee I of the International Commission on Radiological Protection has recommended that the Quality Factor for neutrons should be changed from 10 to 20. This article is an interesting recount of the tale of Q from the viewpoint of an observer which illustrates many of the problems that the selection of protection standards pose. 32 refs., 5 tabs.

  20. Social-psychological factors in the dietary quality of married and single elderly.

    PubMed

    Schafer, R B; Keith, P M

    1982-07-01

    The objective of this study was to examine the social-psychological correlates of diet quality of elderly married couples and elderly single women. The social-psychological factors included: personality, social interaction, and social influence variables. Eighty-two married couples (164 respondents) and 69 single women were randomly selected and interviewed. It was found that social influence variables were more important factors in determining quality of diet than either personality or social interaction variables. The elderly single women's higher quality diet was associated with more reliable sources of influence than those of the elderly married, a condition attributed to the independence and competencies required by their single living arrangements. For married couples, role dissatisfaction had negative consequences for wives' diets, and husbands' involvement in family food decisions had positive consequences for their own diet quality. PMID:7086013

  1. Monte Carlo simulations of neutron spectral fluence, radiation weighting factor and ambient dose equivalent for a passively scattered proton therapy unit

    NASA Astrophysics Data System (ADS)

    Zheng, Yuanshui; Fontenot, Jonas; Taddei, Phil; Mirkovic, Dragan; Newhauser, Wayne

    2008-01-01

    Stray neutron exposures pose a potential risk for the development of secondary cancer in patients receiving proton therapy. However, the behavior of the ambient dose equivalent is not fully understood, including dependences on neutron spectral fluence, radiation weighting factor and proton treatment beam characteristics. The objective of this work, therefore, was to estimate neutron exposures resulting from the use of a passively scattered proton treatment unit. In particular, we studied the characteristics of the neutron spectral fluence, radiation weighting factor and ambient dose equivalent with Monte Carlo simulations. The neutron spectral fluence contained two pronounced peaks, one a low-energy peak with a mode around 1 MeV and one a high-energy peak that ranged from about 10 MeV up to the proton energy. The mean radiation weighting factors varied only slightly, from 8.8 to 10.3, with proton energy and location for a closed-aperture configuration. For unmodulated proton beams stopped in a closed aperture, the ambient dose equivalent from neutrons per therapeutic absorbed dose (H*(10)/D) calculated free-in-air ranged from about 0.3 mSv/Gy for a small scattered field of 100 MeV proton energy to 19 mSv/Gy for a large scattered field of 250 MeV proton energy, revealing strong dependences on proton energy and field size. Comparisons of in-air calculations with in-phantom calculations indicated that the in-air method yielded a conservative estimation of stray neutron radiation exposure for a prostate cancer patient.

  2. Current risk estimates based on the A-bomb survivors data - a discussion in terms of the ICRP recommendations on the neutron weighting factor.

    PubMed

    Rühm, W; Walsh, L

    2007-01-01

    Currently, most analyses of the A-bomb survivors' solid tumour and leukaemia data are based on a constant neutron relative biological effectiveness (RBE) value of 10 that is applied to all survivors, independent of their distance to the hypocentre at the time of bombing. The results of these analyses are then used as a major basis for current risk estimates suggested by the International Commission on Radiological Protection (ICRP) for use in international safety guidelines. It is shown here that (i) a constant value of 10 is not consistent with weighting factors recommended by the ICRP for neutrons and (ii) it does not account for the hardening of the neutron spectra in Hiroshima and Nagasaki, which takes place with increasing distance from the hypocentres. The purpose of this paper is to present new RBE values for the neutrons, calculated as a function of distance from the hypocentres for both cities that are consistent with the ICRP60 neutron weighting factor. If based on neutron spectra from the DS86 dosimetry system, these calculations suggest values of about 31 at 1000 m and 23 at 2000 m ground range in Hiroshima, while the corresponding values for Nagasaki are 24 and 22. If the neutron weighting factor that is consistent with ICRP92 is used, the corresponding values are about 23 and 21 for Hiroshima and 21 and 20 for Nagasaki, respectively. It is concluded that the current risk estimates will be subject to some changes in view of the changed RBE values. This conclusion does not change significantly if the new doses from the Dosimetry System DS02 are used. PMID:17533156

  3. Quality Factor Measurements of Various Types of Quartz Crystal Resonators Operating Near 4 K.

    PubMed

    Galliou, Serge; Goryachev, Maxim; Abbe, Philippe; Vacheret, Xavier; Tobar, Michael E; Bourquin, Roger

    2016-07-01

    Quartz crystal resonators can exhibit huge quality factors (in excess of 1 billion) at liquid-helium temperature. However, they must satisfy a set of conditions to meet this high level of performance. With the help of experimentation, the main conditions are identified, such as the material quality, the energy trapping due to the vibrational mode structure, as well as the corresponding influence of the support mechanism and the effects of the electrodes. PMID:26701342

  4. Quantum Limit of Quality Factor in Silicon Micro and Nano Mechanical Resonators

    PubMed Central

    Ghaffari, Shirin; Chandorkar, Saurabh A.; Wang, Shasha; Ng, Eldwin J.; Ahn, Chae H.; Hong, Vu; Yang, Yushi; Kenny, Thomas W.

    2013-01-01

    Micromechanical resonators are promising replacements for quartz crystals for timing and frequency references owing to potential for compactness, integrability with CMOS fabrication processes, low cost, and low power consumption. To be used in high performance reference application, resonators should obtain a high quality factor. The limit of the quality factor achieved by a resonator is set by the material properties, geometry and operating condition. Some recent resonators properly designed for exploiting bulk-acoustic resonance have been demonstrated to operate close to the quantum mechanical limit for the quality factor and frequency product (Q-f). Here, we describe the physics that gives rise to the quantum limit to the Q-f product, explain design strategies for minimizing other dissipation sources, and present new results from several different resonators that approach the limit. PMID:24247809

  5. Factors associated with the quality of laboratory performance in the United Kingdom external quality assessment scheme for serum growth hormone.

    PubMed

    Seth, J; Hanning, I

    1988-05-31

    A search was made for associations between poor performance in the UK External Quality Assessment Scheme (EQAS) for serum growth hormone (GH), and a range of factors including assay method, laboratory workload and staffing, and Internal Quality Control (IQC) procedures. On the basis of the factors identified as being associated with poor performance we recommend the following. 1. Laboratories using RIA for GH should routinely analyse samples at two dilutions and report a mean result. 2. The use of 125I-GH which is 5 or more weeks old should be avoided. Tracer should also be chromatographed to remove aggregate before use. 3. Laboratories using RIA should avoid using a standard curve which covers too wide a range concentration; a curve midpoint (ie GH concentration to reduce the zero standard binding by 50%) of about 8 mU/l or less is probably acceptable. 4. It should be noted that high workloads present a risk of some loss in quality of responsible for checking IQC data. 6. Laboratories which do not have the resources to maintain fully their own RIA as outlined above should carefully consider use of an unbiased, precise IRMA. The UK EQAS has identified two assays (Boots-Celltech Sucrosep, NETRIA) that appear to meet these criteria [2]. The above observations may also be relevant to immunoassays for other peptide hormones. PMID:3383443

  6. Factors Affecting Parent's Perception on Air Quality-From the Individual to the Community Level.

    PubMed

    Guo, Yulin; Liu, Fengfeng; Lu, Yuanan; Mao, Zongfu; Lu, Hanson; Wu, Yanyan; Chu, Yuanyuan; Yu, Lichen; Liu, Yisi; Ren, Meng; Li, Na; Chen, Xi; Xiang, Hao

    2016-01-01

    The perception of air quality significantly affects the acceptance of the public of the government's environmental policies. The aim of this research is to explore the relationship between the perception of the air quality of parents and scientific monitoring data and to analyze the factors that affect parents' perceptions. Scientific data of air quality were obtained from Wuhan's environmental condition reports. One thousand parents were investigated for their knowledge and perception of air quality. Scientific data show that the air quality of Wuhan follows an improving trend in general, while most participants believed that the air quality of Wuhan has deteriorated, which indicates a significant difference between public perception and reality. On the individual level, respondents with an age of 40 or above (40 or above: OR = 3.252; 95% CI: 1.170-9.040), a higher educational level (college and above: OR = 7.598; 95% CI: 2.244-25.732) or children with poor healthy conditions (poor: OR = 6.864; 95% CI: 2.212-21.302) have much more negative perception of air quality. On the community level, industrial facilities, vehicles and city construction have major effects on parents' perception of air quality. Our investigation provides baseline information for environmental policy researchers and makers regarding the public's perception and expectation of air quality and the benefits to the environmental policy completing and enforcing. PMID:27187432

  7. Comparison of mean quality factors proposed by ICRP, ICRU and NASA

    NASA Astrophysics Data System (ADS)

    Sato, Tatsuhiko; Niita, Koji; Endo, Akira

    2012-07-01

    Astronauts are exposed to primary cosmic-rays and secondary particles produced by them through interaction with the atoms of the spacecraft material and those of the human body. For the radiation risk estimation of astronauts, not only organ absorbed doses but also their mean quality factors must be evaluated, since radiation weighting factor as defined by ICRP60 is not suitable for use in space dosimetry due to its very simplified concept. Three relationships were proposed for expressing the radiation quality by different organizations; (1) International Commission on Radiological Protection (ICRP) defined the quality factor based on LET in water, Q(L), in ICRP60, (2) in International Commission on Radiation Units and Measurements (ICRU) Report 40, a quality factor Q(y) is defined as a function of lineal energy, y, for spherical liquid water of 1 mm in diameter, Q(y), and (3) National Aeronautics and Space Administration (NASA) proposed those for solid cancer and leukemia separately based on charge and energy of particles, QNASA(Z,E), in NASA/TP-2011-216155. The Q(L) relationship is most simple and widely used in space dosimetry, but the latter two relationships consider the difference of the track structure of the various heavy ions in tissue due to the production of d-rays, which is very important in the risk estimation for the HZE-particle exposure. We therefore calculated the mean quality factors in organs and tissues in the ICRP reference voxel phantoms for various particles, using the PHITS code coupled with the ICRP, ICRU and NASA Q-functions. An isotropic irradiation of the phantom was assumed in the calculation. The details of the calculation procedure will be described, together with the comparison of mean quality factors obtained from the 3 relationships.

  8. Preadoptive factors predicting lesbian, gay, and heterosexual couples' relationship quality across the transition to adoptive parenthood.

    PubMed

    Goldberg, Abbie E; Smith, Julianna Z; Kashy, Deborah A

    2010-06-01

    The authors examined preadoptive factors as predictors of relationship quality (love, ambivalence, and conflict) among 125 couples (44 lesbian couples, 30 gay male couples, and 51 heterosexual couples) across the 1st year of adoptive parenthood. On average, all new parents experienced declines in their relationship quality across the 1st year of parenthood regardless of sexual orientation, with women experiencing steeper declines in love. Parents who, preadoption, reported higher levels of depression, greater use of avoidant coping, lower levels of relationship maintenance behaviors, and less satisfaction with their adoption agencies reported lower relationship quality at the time of the adoption. The effect of avoidant coping on relationship quality varied by gender. Parents who, preadoption, reported higher levels of depression, greater use of confrontative coping, and higher levels of relationship maintenance behaviors reported greater declines in relationship quality. These findings have implications for professionals who work with adoptive parents both pre- and postadoption. PMID:20545395

  9. Poor sleep quality as a risk factor for lapse following a cannabis quit attempt.

    PubMed

    Babson, Kimberly A; Boden, Matthew Tyler; Harris, Alex H; Stickle, Timothy R; Bonn-Miller, Marcel O

    2013-04-01

    Treatments for cannabis dependence are associated with high rates of lapse/relapse, underscoring the importance of identifying malleable risk factors that are associated with quit failure. Whereas research has demonstrated that poor sleep quality following cannabis discontinuation is related to subsequent use, there has yet to be an examination of whether poor sleep quality prior to a quit attempt results in a similar pattern of lapse. The present study addressed this gap by examining the role of pre-quit sleep quality on early lapse to cannabis use following a self-guided quit attempt, among 55 cannabis dependent military veterans. Results indicated that participants who experienced poor pre-quit sleep quality had greater risk for lapse within the first 2 days (out of 7) following their quit attempt. Findings are discussed in terms of improving treatments for individuals who report poor sleep quality prior to a cannabis quit attempt. PMID:23098380

  10. Sleep Quality and Factors Influencing Self-Reported Sleep Duration and Quality in the General Internal Medicine Inpatient Population

    PubMed Central

    Dobing, Selina; Frolova, Natalia; McAlister, Finlay

    2016-01-01

    Background Sleep quality in hospitalized Canadian General Internal Medicine patients is not well characterized. Our goals were to characterize hospital sleep quality in this population and identify potentially modifiable barriers to good sleep. Methods GIM inpatients at a quaternary centre in Edmonton, Canada completed a survey, including the Verran-Snyder Halpern (VSH) questionnaire, to characterize the previous night’s sleep within 48 hours prior to discharge. A chart review was also completed to assess comorbidities, discharge diagnoses, and pharmaceutical sleep aid use. Results Patients reported significantly worse nighttime sleep duration in hospital compared with home (mean 5.5 versus 7.0 hours per night, p < 0.0001). Sleep quality was poor, as measured by the VSH disturbance (mean 371), effectiveness (190), and supplementation (115) subscales. Variables independently associated with poorer sleep duration in multivariable regression include prior diagnosis of sleep disorder and multi-patient occupancy rooms. Age, sex, admitting diagnosis, length of stay, frequency of vital checks, and use of sleep pharmaceuticals during the index hospitalization were not associated with sleep duration. The most frequently reported reasons for poor sleep included noise (59%), nursing interruptions (30%), uncomfortable beds (18%), bright lights (16%), unfamiliar surroundings (14%), and pain (9%). Conclusions Sleep quality for GIM inpatients is significantly worse in hospital than at home. There is a need to test non-pharmacologic interventions to address the most frequently identified factors causing poor sleep hygiene for GIM inpatients. PMID:27280292

  11. Anomalous thickness dependence of quality factor in TiN film resonators grown on functionalized Si substrates

    NASA Astrophysics Data System (ADS)

    Xu, Peng; Kohler, Tim; Lock, Evgeniya; Rosen, Yaniv; Ramanayaka, Aruna; Guchhait, Samaresh; Osborn, Kevin

    Various properties affect the quality factor of superconducting resonators at millikelvin temperatures including the presence of nanoscale interfacial dielectric films and residual quasiparticles. Superconducting titanium nitride is polycrystalline such that growth phases may also affect the resonator quality. Here, we functionalize Si substrates in different hydrophobic and hydrophilic plasma environments, sputter titanium nitride on top and pattern the latter films into resonators. For each functionalization we study the quality factor dependence on the superconducting film thickness, where the thicknesses are changed only between 25 and 50 nm. As expected, most functionalizations reveal very little quality factor dependence on superconducting film thickness. However, other functionalizations dramatically, and even anomalously, increase or decrease the quality with thickness. For example, oxygen plasma functionalization causes the quality factor to increase by a factor of more than ten at single photon power with increased thickness. We report on the progress towards finding the intrinsic reason for strong quality factor dependences on surface functionalization.

  12. Psychosocial factors as predictors of quality of life in chronic portuguese patients

    PubMed Central

    2014-01-01

    Background Chronic illnesses are diseases of long duration and generally of slow progression. They cause significant quality of life impairment. The aim of this study was to analyse psychosocial predictors of quality of life and of subjective well-being in chronic Portuguese patients. Methods Chronic disease patients (n = 774) were recruited from central Portuguese Hospitals. Participants completed self-reported questionnaires assessing socio-demographic, clinical, psychosocial and outcome variables: quality of life (HRQL) and subjective well-being (SWB). MANCOVA analyses were used to test psychosocial factors as determinants of HRQL and SWB. Results After controlling for socio-demographic and clinical variables, results showed that dispositional optimism, positive affect, spirituality, social support and treatment adherence are significant predictors of HRQL and SWB. Similar predictors of quality of life, such as positive affect, treatment adherence and spirituality, were found for subgroups of disease classified by medical condition. Conclusions The work identifies psychosocial factors associated with quality of life. The predictors for the entire group of different chronic diseases are similar to the ones found in different chronic disease subgroups: positive affect, social support, treatment adherence and spirituality. Patients with more positive affect, additional social support, an adequate treatment adherence and a feel-good spirituality, felt better with the disease conditions and consequently had a better quality of life. This study contributes to understanding and improving the processes associated with quality of life, which is relevant for health care providers and chronic diseases support. PMID:24405802

  13. Quality-Factor Enhancement of Nanoelectromechanical Systems by Capacitive Driving Beyond Resonance

    NASA Astrophysics Data System (ADS)

    Barois, T.; Perisanu, S.; Poncharal, P.; Vincent, P.; Purcell, S. T.; Ayari, A.

    2016-07-01

    Nanoelectromechanical systems are considered as ultrasensitive devices for mass and force detection. Capacitive actuation is widely used in these devices but is known to degrade the quality factor of the resonator due to dc electrostatic damping. We report the enhancement of the quality factor of SiC vibrating nanowires detected nano-optomechanically and electrically by applying an ac capacitive driving at a frequency above both the resonance frequency and the electrical cutoff frequency. Self-oscillations are demonstrated for optimal conditions. We develop an analytical model of the phenomenon and show that it can lead to an improvement of the force sensitivity.

  14. Enhancement in Quality Factor of SRF Niobium Cavities by Material Diffusion

    SciTech Connect

    Dhakal, Pashupati; Ciovati, Gianluigi; Kneisel, Peter K.; Myneni, Ganapati Rao

    2015-06-01

    An increase in the quality factor of superconducting radiofrequency cavities is achieved by minimizing the surface resistance during processing steps. The surface resistance is the sum of temperature independent residual resistance and temperature/material dependent Bardeen-Cooper-Schrieffer (BCS) resistance. High temperature heat treatment usually reduces the impurities concentration from the bulk niobium, lowering the residual resistance. The BCS part can be reduced by selectively doping non-magnetic impurities. The increase in quality factor, termed as Q-rise, was observed in cavities when titanium or nitrogen thermally diffused in the inner cavity surface.

  15. Pressure dependence of quality factors of graphene nano-mechanical resonators

    NASA Astrophysics Data System (ADS)

    Khaksaran, M. Hadi; Yanik, Cenk; Karakan, M. Cagatay; Ari, Atakan Bekir; Hanay, M. Selim; Kaya, Ismet I.

    In recent few years, low mass density and high stiffness of graphene has drawn attention for developing high frequency mechanical resonators with high quality factor at the same time. As a single-atom thick material, graphene has many desirable properties for high-frequency sensor applications compared to top-down nano-mechanical resonators . In this work we address the energy dissipation in graphene resonators due to viscous damping. We experimentally measure the pressure dependence of the quality factor of a graphene nano-mechanical resonator to understand its interaction with fluids at high frequencies. This work is supprted by TUBITAK under Grant Number 112T990.

  16. Bioaccumulation factor portions of the proposed water quality guidance for the Great Lakes system

    SciTech Connect

    Not Available

    1993-08-01

    Bioaccumulation factors are being proposed to be used in the derivation of human health and wildlife criteria specific for the Great Lakes Water Quality Initiative (GLWQI). Adopting the use of bioaccumulation factors instead of bioconcentration factors presents a significant change from current Agency guidance. Because there is not an established procedure for determining bioaccumulation factors, national guidance may be eventually modeled on the proposed GLWQI Guidance. The document was produced to facilitate review of and comment on the proposed procedure for determining bioaccumulation factors by persons who may not keep abreast of Federal Register notices, including the larger scientific community. The document is composed of two chapters and one appendix. Chapter 1 describes the development of the proposed procedure for determining bioaccumulation factors; Chapter 2 presents the proposed methodology for development of bioaccumulation factors.

  17. The Quality of Different Types of Child Care at 10 and 18 Months: A Comparison between Types and Factors Related to Quality

    ERIC Educational Resources Information Center

    Leach, Penelope; Barnes, Jacqueline; Malmberg, Lars-Erik; Sylva, Kathy; Stein, Alan

    2008-01-01

    The quality of care offered in four different types of non-parental child care to 307 infants at 10 months old and 331 infants at 18 months old was compared and factors associated with higher quality were identified. Observed quality was lowest in nurseries at each age point, except that at 18 months they offered more learning activities. There…

  18. Neutron measurements onboard the space shuttle

    NASA Technical Reports Server (NTRS)

    Badhwar, G. D.; Keith, J. E.; Cleghorn, T. F.

    2001-01-01

    The radiation environment inside a shielded volume is highly complex, consisting of both charged and neutral particles. Since the inception of human space flights, the charged particle component has received virtually all of the attention. There is however, a significant production of secondary neutrons, particularly from the aluminum structure in low earth orbiting spacecrafts. The interactions of galactic cosmic rays (GCR), and solar energetic particles with the earth's atmosphere produce a non-isotropic distribution of albedo neutrons. Inside any reasonable habitable module, the average radiation quality factor of neutrons is about 4-5 times larger than the corresponding average quality factor of charged particles. The measurement of neutrons and their energy spectra is a difficult problem due the intense sources of charged particles. This paper reviews the results of Shuttle flight experiments (made during both solar maximum and solar minimum) to measure the contribution of neutrons to the dose equivalent, as well as theoretical calculations to estimate the appropriate range of neutron energies that contribute most to the dose equivalent. Published by Elsevier Science Ltd.

  19. Neutron measurements onboard the space shuttle.

    PubMed

    Badhwar, G D; Keith, J E; Cleghorn, T F

    2001-06-01

    The radiation environment inside a shielded volume is highly complex, consisting of both charged and neutral particles. Since the inception of human space flights, the charged particle component has received virtually all of the attention. There is however, a significant production of secondary neutrons, particularly from the aluminum structure in low earth orbiting spacecrafts. The interactions of galactic cosmic rays (GCR), and solar energetic particles with the earth's atmosphere produce a non-isotropic distribution of albedo neutrons. Inside any reasonable habitable module, the average radiation quality factor of neutrons is about 4-5 times larger than the corresponding average quality factor of charged particles. The measurement of neutrons and their energy spectra is a difficult problem due the intense sources of charged particles. This paper reviews the results of Shuttle flight experiments (made during both solar maximum and solar minimum) to measure the contribution of neutrons to the dose equivalent, as well as theoretical calculations to estimate the appropriate range of neutron energies that contribute most to the dose equivalent. PMID:11852943

  20. Personnel neutron dose assessment upgrade: Volume 2, Field neutron spectrometer for health physics applications

    SciTech Connect

    Brackenbush, L.W.; Reece, W.D.; Miller, S.D.; Endres, G.W.R.; Durham, J.S.; Scherpelz, R.I.; Tomeraasen, P.L.; Stroud, C.M.; Faust, L.G.; Vallario, E.J.

    1988-07-01

    Both the (ICRP) and the (NCPR) have recommended an increase in neutron quality factors and the adoption of effective dose equivalent methods. The series of reports entitled Personnel Neutron Dose Assessment Upgrade (PNL-6620) addresses these changes. Volume 1 in this series of reports (Personnel Neutron Dosimetry Assessment) provided guidance on the characteristics, use, and calibration of personnel neutron dosimeters in order to meet the new recommendations. This report, Volume 2: Field Neutron Spectrometer for Health Physics Applications describes the development of a portable field spectrometer which can be set up for use in a few minutes by a single person. The field spectrometer described herein represents a significant advance in improving the accuracy of neutron dose assessment. It permits an immediate analysis of the energy spectral distribution associated with the radiation from which neutron quality factor can be determined. It is now possible to depart from the use of maximum Q by determining and realistically applying a lower Q based on spectral data. The field spectrometer is made up of two modules: a detector module with built-in electronics and an analysis module with a IBM PC/reg sign/-compatible computer to control the data acquisition and analysis of data in the field. The unit is simple enough to allow the operator to perform spectral measurements with minimal training. The instrument is intended for use in steady-state radiation fields with neutrons energies covering the fission spectrum range. The prototype field spectrometer has been field tested in plutonium processing facilities, and has been proven to operate satisfactorily. The prototype field spectrometer uses a /sup 3/He proportional counter to measure the neutron energy spectrum between 50 keV and 5 MeV and a tissue equivalent proportional counter (TEPC) to measure absorbed neutron dose.

  1. Space Radiation Quality Factors and the Delta Ray Dose and Dose-Rate Reduction Effectiveness Factor.

    PubMed

    Cucinotta, Francis A; Cacao, Eliedonna; Alp, Murat

    2016-03-01

    In this paper, the authors recommend that the dose and dose-rate effectiveness factor used for space radiation risk assessments should be based on a comparison of the biological effects of energetic electrons produced along a cosmic ray particles path in low fluence exposures to high dose-rate gamma-ray exposures of doses of about 1 Gy. Methods to implement this approach are described. PMID:26808878

  2. Neutron dosimetry in low-earth orbit using passive detectors.

    PubMed

    Benton, E R; Benton, E V; Frank, A L

    2001-06-01

    This paper summarizes neutron dosimetry measurements made by the USF Physics Research Laboratory aboard US and Russian LEO spacecraft over the past 20 years using two types of passive detector. Thermal/resonance neutron detectors exploiting the 6Li(n,T) alpha reaction were used to measure neutrons of energies <1 MeV. Fission foil neutron detectors were used to measure neutrons of energies above 1 MeV. While originally analysed in terms of dose equivalent using the NCRP-38 definition of quality factor, for the purposes of this paper the measured neutron data have been reanalyzed and are presented in terms of ambient dose equivalent. Dose equivalent rate for neutrons <1 MeV ranged from 0.80 microSv/d on the low altitude, low inclination STS-41B mission to 22.0 microSv/d measured in the Shuttle's cargo bay on the highly inclined STS-51F Spacelab-2 mission. In one particular instance a detector embedded within a large hydrogenous mass on STS-61 (in the ECT experiment) measured 34.6 microSv/d. Dose equivalent rate measurements of neutrons >1 MeV ranged from 4.5 microSv/d on the low altitude STS-3 mission to 172 microSv/d on the ~6 year LDEF mission. Thermal neutrons (<0.3 eV) were observed to make a negligible contribution to neutron dose equivalent in all cases. The major fraction of neutron dose equivalent was found to be from neutrons >1 MeV and, on LDEF, neutrons >1 MeV are responsible for over 98% of the total neutron dose equivalent. Estimates of the neutron contribution to the total dose equivalent are somewhat lower than model estimates, ranging from 5.7% at a location under low shielding on LDEF to 18.4% on the highly inclined (82.3 degrees) Biocosmos-2044 mission. PMID:11852945

  3. The quality of risk factor screening during antenatal consultations in Niger.

    PubMed

    Prual, A; Toure, A; Huguet, D; Laurent, Y

    2000-03-01

    A decade after the first International Conference on Safe Motherhood, maternal mortality remains very high in most West African countries, even in capital cities. The detection of high risk pregnancies, known as the risk approach, during antenatal consultations has been the basis of most maternal and child health programmes over the last decade. The effectiveness of antenatal care as a tool to prevent or predict obstetric complications is being questioned more and more. In addition to the scarcity of reliable data about the predictivity of most risk factors, the quality of the screening must be questioned. The goal of this study was to assess the frequency of risk factors among a sample of pregnant women attending antenatal care in Niger and to assess the quality of the screening of those risk factors. Overall, 330 pregnant women were enrolled in the study. Each woman was examined twice: the first time by a midwife, the second time by one of the authors but without knowledge of the results of the first consultation. Fifty-five percent of pregnant women had at least one risk factor, 31% had more than one. Ninety-one percent of the risk factors were detected at interview. The following risk factors were not systematically searched for by midwives: height (48.5%), blood pressure (43.6%), glycosuria (40.6%), vaginal bleeding (38.2%), oedema (37.3%), parity (17%), age (16%), previous caesarean section (15.2%), previous stillbirth (15.2%) and previous miscarriages (14.8%). This study has shown that, in Niger, the quality of screening for risk factors during antenatal consultation is poor. In the urban settings where this study took place, lack of personnel, lack of equipment, lack of time and poor compliance by women cannot be made responsible for this situation. While screening of these risk factors continues as policy, the quality of screening must be dramatically improved. PMID:10731230

  4. Factors predicting team climate, and its relationship with quality of care in general practice

    PubMed Central

    2009-01-01

    Background Quality of care in general practice may be affected by the team climate perceived by its health and non-health professionals. Better team working is thought to lead to higher effectiveness and quality of care. However, there is limited evidence available on what affects team functioning and its relationship with quality of care in general practice. This study aimed to explore individual and practice factors that were associated with team climate, and to explore the relationship between team climate and quality of care. Methods Cross sectional survey of a convenience sample of 14 general practices and their staff in South Tyneside in the northeast of England. Team climate was measured using the short version of Team Climate Inventory (TCI) questionnaire. Practice characteristics were collected during a structured interview with practice managers. Quality was measured using the practice Quality and Outcome Framework (QOF) scores. Results General Practitioners (GP) had a higher team climate scores compared to other professionals. Individual's gender and tenure, and number of GPs in the practice were significantly predictors of a higher team climate. There was no significant correlation between mean practice team climate scores (or subscales) with QOF scores. Conclusion The absence of a relationship between a measure of team climate and quality of care in this exploratory study may be due to a number of methodological problems. Further research is required to explore how to best measure team functioning and its relationship with quality of care. PMID:19653911

  5. Assessment Scales, Associated Factors and the Quality of Life Score in Pregnant Women in Iran.

    PubMed

    Kazemi, Farideh; Nahidi, Fatemeh; Kariman, Nourossadat

    2016-01-01

    Women experience physical, chemical, endocrine gland and organ changes during pregnancy that limit their activities and reduce their quality of life. The present study was conducted to investigate the quality of life in pregnant women in Iran, the assessment scales used to measure this variable and the factors associated with it.The present study searched databases including Science Direct, PubMed, Scopus, SID, Iranmedex, Mahiran, IranDoc and Google Scholar using keywords such as pregnant women, Iran, quality of life, pregnancy and prenatal and their Persian equivalents to find relevant articles conducted in Iran and ultimately found 20 articles to review without any regard for their time, language and publication site.Studies conducted in Iran to assess the quality of life in pregnant women have used four tools, including the SF-36, the WHOQOL-BRIEF, the SF-12 and the Nausea and Vomiting of Pregnancy-Specific Health-Related Quality of Life Questionnaire. The mean quality of life score obtained using these different tools varied from 61.18±13.21 to 66.48±15.57. Social support, socioeconomic status, the pregnancy being wanted, satisfaction with life and sexual function were related directly to the quality of life, while prenatal mental disorders, the severity of pregnancy nausea and vomiting and sleep disorders were related inversely to it.Given the lack of a specific tool designed to assess the quality of life in pregnant women, general tools were used for its assessment. Further studies are thus required to design a specific localized tool and to also assess the relationship between the quality of life and its associated factors. PMID:27241421

  6. A method for assessing the quality of life of cancer patients: replication of the factor structure.

    PubMed Central

    Bliss, J. M.; Selby, P. J.; Robertson, B.; Powles, T. J.

    1992-01-01

    The psychometric properties of a method of measuring the quality of life of cancer patients based on multiple linear analogue scales have been assessed in a group of 294 patients with breast cancer attending one clinical unit. The method was found to be readily managed by patients although a small number of scales presented difficulties of understanding to patients and difficulties of analysis. The scales distinguished readily between patients of different disease and treatment status. Factor analysis revealed a 5 factor structure which we interpret as relating to physical activities of everyday living, emotional disturbance, alimentary disturbances, appearance and cosmetic problems and a fifth factor which is more difficult to interpret and includes impairment of speech, writing and concentration. We feel the essential factors determining quality of life in cancer patients have been demonstrated in this and our earlier studies and there is now a substantial level of agreement in the factors that have been identified by groups taking quite different approaches. The major factors determining quality of life in cancer patients are now known and should be assessed in clinical research and clinical trials. The method by which they should be assessed is not as yet so clear. PMID:1616871

  7. Miniaturisation and high quality factor of spiral meander spurline resonator for microwave oscillator

    NASA Astrophysics Data System (ADS)

    Cho, Sung-Jin; Kim, Nam-Young

    2013-04-01

    The spiral meander spurline structure is an optimal solution for a reduced resonator size and a high Quality factor (Q-factor) compared to other conventional spurline structures. The spiral meander spurline resonator shows not only 38% reduced dimensional effect, but also 16% improved Q-factor compared with conventional meander spurline resonator. Moreover, in order to get more high quality factor, we analysed spurline slot width variation and designed the symmetric dual spiral meander structure, which has a 46.87% improved Q-factor compare with a single spiral meander. The symmetric dual spiral meander structure resonator performance results are shown in a return loss of -0.76 dB, an insertion loss of -46.32 dB, and a quality factor of 235 at 6.4 GHz C-band application. In addition, according to the design and performance of the resonator, we can derive from this performance a low phase noise oscillator. The oscillators using symmetric dual spiral meander structure resonator shows good phase noise performances of -104.43 dBc/Hz at a 100 kHz offset from the carrier frequencies of 6.38 GHz at output powers of 12.2 dBm, respectively.

  8. The Transverse Asymmetry A{sub T}, from Quasi-elastic {sup 3}{ovr He}({rvec e}, e{prime}) Process and the Neutron Magnetic Form Factor

    SciTech Connect

    Wang Xu; Dipangkar Dutta; Feng Xiong; Brian Anderson; Leonard Auerbach; Todd Averett; William Bertozzi; Tim Black; John Calarco; Lawrence Cardman; Gordon Cates; Zhengwei Chai; Jian-ping Chen; Seonho Choi; Eugene Chudakov; Steve Churchwell; G.S. Corrado; C. Crawford; Daniel Dale; Alexandre Deur; Pibero Djawotho; Bradley Filippone; John Finn; Haiyan Gao; Ronald Gilman; Oleksandr Glamazdin; Charles Glashausser; Walter Gloeckle; J. Golak; Javier Gomez; Viktor Gorbenko; Jens-ole Hansen; F. Hersman; Douglas Higinbotham; Richard Holmes; Calvin Howell; Emlyn Hughes; Thomas Humensky; Sebastien Incerti; Cornelis De Jager; John Jensen; Xiaodong Jiang; C.E. Jones; Mark Jones; R. Kahl; H. Kamada; A. Kievsky; Ioannis Kominis; Wolfgang Korsch; Kevin Kramer; Gerfried Kumbartzki; Michael Kuss; Enkeleida Lakuriqi; Meihua Liang; Nilanga Liyanage; John Lerose; Sergey Malov; Demetrius Margaziotis; J.W. Martin; Kathy Mccormick; Robert Mckeown; Kevin Mcilhany; Zein-eddine Meziani; Robert Michaels; G.W. Miller; Joseph Mitchell; Sirish Nanda; E. Pace; Tina Pavlin; Gerassimos Petratos; Roman Pomatsalyuk; D. Pripstein; David Prout; Ronald Ransome; Yves Roblin; Marat Rvachev; Arunava Saha; G. Salme; Michael Schnee; Taeksu Shin; Karl Slifer; Paul Souder; Steffen Strauch; Riad Suleiman; Mark Sutter; Bryan Tipton; Luminita Todor; Michele Viviani; Branislav Vlahovic; J. Watson; Claude Williamson; H. Witala; Bogdan Wojtsekhowski; Jen-chuan Yeh; Piotr Zolnierczuk

    2000-10-01

    We have measured the transverse asymmetry from inclusive scattering of longitudinally polarized electrons from polarized {sup 3}He nuclei at quasi-elastic kinematics in Hall A at Jefferson Lab with high statistical and systematic precision. The neutron magnetic form factor was extracted based on Faddeev calculations with an experimental uncertainty of less than 2%.

  9. Factors controlling reservoir quality in tertiary sandstones and their significance to geopressured geothermal production

    SciTech Connect

    Loucks, R.G.; Richmann, D.L.; Milliken, K.L.

    1981-01-01

    Variable intensity of diagenesis is the factor primarily responsible for contrasting regional reservoir quality of Tertiary sandstones from the upper and lower Texas coast. Detailed comparison of Frio sandstone from the Chocolate Bayou/Danbury Dome area, Brazoria County, and Vicksburg sandstones from the McAllen Ranch Field area, Hidalgo County, reveals that extent of diagenetic modification is most strongly influenced by (1) detrital mineralogy and (2) regional geothermal gradients. The regional reservoir quality of Frio sandstones from Brazoria County is far better than that characterizing Vicksburg sandstones from Hidalgo County, especially at depths suitable for geopressured geothermal energy production. However, in predicting reservoir quality on a site-specific basis, locally variable factors such as relative proportions for porosity types, pore geometry as related to permeability, and local depositional environment must also be considered. Even in an area of regionally favorable reservoir quality, such local factors can significantly affect reservoir quality and, hence, the geothermal production potential of a specific sandstone unit.

  10. Factors Influencing Older Worker Quality of Life and Intent to Continue to Work

    ERIC Educational Resources Information Center

    Spokus, Diane

    2008-01-01

    High turnover has been a major problem in healthcare organizations. The purpose of this study was to examine the relationship among job characteristics, social support, and organizational characteristics on quality of the working life. Subsequently, the intent was to examine how those factors collectively influence turnover intention. A…

  11. Frame Factors and a Quality Assurance Agency in an "Embryonic" Higher Education System

    ERIC Educational Resources Information Center

    Hopkin, Anthony G.

    2004-01-01

    Using the Affiliations Unit of the University of Botswana as a case study, this paper explores how the operational milieu of an External Quality Assurance Agency (EQAA) impacts on its role and function. This milieu is described and selected frame factors are identified and evaluated, including the size of the country; the role of a hegemonic…

  12. Frame Factors and a Quality Assurance Agency in an 'Embryonic' Higher Education System

    ERIC Educational Resources Information Center

    Hopkin, Anthony

    2004-01-01

    Using the Affiliations Unit of the University of Botswana as a case study, this paper explores how the operational milieu of an External Quality Assurance Agency (EQAA) impacts on its role and function. This milieu is described and selected frame factors are identified and evaluated, including the size of the country; the role of a hegemonic…

  13. Testing the Factor Structure of the Family Quality of Life Survey--2006

    ERIC Educational Resources Information Center

    Isaacs, B.; Wang, M.; Samuel, P.; Ajuwon, P.; Baum, N.; Edwards, M.; Rillotta, F.

    2012-01-01

    Background: Although the Family Quality of Life Survey--2006 (FQOLS-2006) is being used in research, there is little evidence to support its hypothesised domain structure. The purpose of this study was to test the domain structure of the survey using confirmatory factor analysis. Method: Samples from Australia, Canada, Nigeria and the USA were…

  14. Quality factor and finesse optimization in buried InGaAsP/InP ring resonators

    NASA Astrophysics Data System (ADS)

    Ciminelli, C.; Passaro, V. M. N.; Dell'Olio, F.; Armenise, M. N.

    2009-06-01

    Quality factor and finesse of buried In1 xGaxAsyP1 y / InP ring resonators have been optimized in this paper by a very general modelling technique. Limiting effect of propagation loss within the ring has been investigated using a three-dimensional (3D) highly accurate complex mode solver based on mode matching method to analyze bending loss dependence on ring radius and wavelength. Coupling between straight input/output (I/O) bus waveguides and ring resonator has been studied by 3D Beam Propagation Method (BPM), deriving coupling loss and coupling coefficient for a large range of ring radius and bus waveguides-ring distance values (for both polarizations). Ring resonator has been modelled by the transfer-matrix approach, while finesse and quality factor dependence on radius has been estimated for two resonator architectures (including one or two I/O bus waveguides) and for quasi-TE and quasi-TM modes. Guiding structure has been optimized to enhance resonator performance. The modelling approach has been validated by comparing results obtained by our algorithm with experimental data reported in literature. Influence of rejection (at resonance wavelength) at through port on quality factor and finesse has been widely discussed. A quality factor larger than 8105 has been predicted for the ring resonator employing only one I/O bus waveguide and having a radius of 400 mm. This resonator exhibits a rejection of -8 dB at through port.

  15. Measurement Model Quality, Sample Size, and Solution Propriety in Confirmatory Factor Models

    ERIC Educational Resources Information Center

    Gagne, Phill; Hancock, Gregory R.

    2006-01-01

    Sample size recommendations in confirmatory factor analysis (CFA) have recently shifted away from observations per variable or per parameter toward consideration of model quality. Extending research by Marsh, Hau, Balla, and Grayson (1998), simulations were conducted to determine the extent to which CFA model convergence and parameter estimation…

  16. A Review of Research on Factors that Impact Aspects of Online Discussions Quality

    ERIC Educational Resources Information Center

    Spatariu, Alexandru; Quinn, Linda F.; Hartley, Kendall

    2007-01-01

    In support of online discussions research, this review classifies and describes instructional interventions and learner characteristics that affect the quality of discussions. The review will help educators better understand factors such as group structure, mentoring, argumentation, and learner characteristics that play a role in shaping online…

  17. Factors Influencing Quality of Life of Hungarian Postmenopausal Women Screened by Osteodensitometry

    ERIC Educational Resources Information Center

    Maroti-Nagy, Agnes; Paulik, Edit

    2011-01-01

    The aim of our study was to evaluate factors influencing health related quality of life in Hungarian postmenopausal women who underwent osteodensitometry. A questionnaire-based cross-sectional study was carried out; 359 women aged over 40 years were involved, attending the outpatient Bone Densitometry Centre of Szeged. Two kinds of tools were…

  18. The Effects of Psychosocial Factors on Quality of Life among Individuals with Chronic Pain

    ERIC Educational Resources Information Center

    Lee, Gloria K.; Chronister, Julie; Bishop, Malachy

    2008-01-01

    This study investigated the psychosocial factors affecting the quality of life (QOL) of 171 individuals with chronic pain. Participants completed a battery of self-rated inventories measuring three sets of predictor variables--demographic (age, gender, income, marital status), pain-specific (chronicity, severity, duration, frequency, pain…

  19. Factor Analysis of Quality of Life for Individuals with Severe Disabilities in Transition.

    ERIC Educational Resources Information Center

    Lin, Hung-Chih

    A study of 398 young adults (ages 21-26) with severe disabilities who had been out of school for 1.75 to 5 years was conducted to validate a four-factor model of quality of life for youth with severe disabilities in transition from school to community and from youth to adulthood. Information was gathered on life satisfaction, employment-economic…

  20. Exploring Factors Influencing Collaborative Knowledge Construction in Online Discussions: Student Facilitation and Quality of Initial Postings

    ERIC Educational Resources Information Center

    Ioannou, Andri; Demetriou, Skevi; Mama, Maria

    2014-01-01

    Although lots of studies have investigated collaborative knowledge construction in online courses, the factors influencing this process are yet to be fully determined. This study provides quantitative and qualitative types of evidence on how (naturally emerged) student facilitation and quality of initial postings influence collaborative knowledge…

  1. Factors Influencing Health-Related Quality of Life of Overweight and Obese Children in South Korea

    ERIC Educational Resources Information Center

    Kim, Hee Soon; Park, Jiyoung; Ma, Yumi; Ham, Ok Kyung

    2013-01-01

    The purpose of this study was to identify factors influencing health-related quality of life (HRQoL) of overweight and obese children in Korea. This study employed a cross-sectional descriptive study design. A total of 132 overweight and obese children participated in the study. Anthropometric measurements included body mass index, percent body…

  2. Evaluating Journal Quality: Is the H-Index a Better Measure than Impact Factors?

    ERIC Educational Resources Information Center

    Hodge, David R.; Lacasse, Jeffrey R.

    2011-01-01

    Objectives: This study evaluates the utility of a new measure--the h-index--that may provide a more valid approach to evaluating journal quality in the social work profession. Method: H-index values are compared with Thomson ISI 5-year impact factors and expert opinion. Results: As hypothesized, the h-index correlates highly with ISI 5-year impact…

  3. High quality factor subwavelength grating waveguide micro-ring resonator based on trapezoidal silicon pillars.

    PubMed

    Wang, Zheng; Xu, Xiaochuan; Fan, Donglei; Wang, Yaguo; Chen, Ray T

    2016-07-15

    Subwavelength grating waveguide-based micro-ring resonators (SWGMRs) are a promising platform for research in light-matter interaction. However, it is extremely difficult to achieve small radius SWGMR devices (e.g., 5 μm) with satisfying quality factors (e.g., ∼10,000). One major issue is the large bend loss of small radius SWGMRs. In this work, we report the use of trapezoidal silicon pillars instead of conventional rectangular silicon pillars as building blocks of SWGMRs. We found that an asymmetric effective refractive index profile created by trapezoidal silicon pillars can significantly reduce the bend loss and therefore increase the quality factors of SWGMRs. For the first time to the best of our knowledge, we have experimentally demonstrated a 5 μm radius SWGMR made of trapezoidal silicon pillars (T-SWGMR) with an applicable quality factor as high as 11,500, 4.6 times of that (∼2800) offered by a conventional SWGMR made of rectangular silicon pillars, which indicates an 81.4% reduction of the propagation loss. This approach can also be readily employed to enhance SWGMRs with larger radii. We have also experimentally demonstrated a 10 μm radius T-SWGMR with a quality factor as high as 45,000, which indicates a propagation loss as low as 6.07 dB/cm. PMID:27420539

  4. Quality of Drawing as a Factor in the Interpretation of Figure Drawings.

    ERIC Educational Resources Information Center

    Johnson, Frank A.; Greenberg, Roger P.

    1978-01-01

    The drawings of 32 poliomyelitis patients and their matched controls were examined to see whether figure drawings primarily reflect the subject's projection of psychological state, ability to draw, or some combination of these two factors. Quality of drawing may at times be the overwhelming determinant of clinical and research findings.…

  5. Evaluated cross-section libraries and kerma factors for neutrons up to 100 MeV on {sup 12}C

    SciTech Connect

    Chadwick, M.B.; Blann, M.; Cox, L.; Young, P.G.; Meigooni, A.

    1995-04-11

    A program is being carried out at Lawrence Livermore National Laboratory to develop high-energy evaluated nuclear data libraries for use in Monte Carlo simulations of cancer radiation therapy. In this report we describe evaluated cross sections and kerma factors for neutrons with incident energies up to 100 MeV on {sup 12}C. The aim of this effort is to incorporate advanced nuclear physics modeling methods, with new experimental measurements, to generate cross section libraries needed for an accurate simulation of dose deposition in fast neutron therapy. The evaluated libraries are based mainly on nuclear model calculations, benchmarked to experimental measurements where they exist. We use the GNASH code system, which includes Hauser-Feshbach, preequilibrium, and direct reaction mechanisms. The libraries tabulate elastic and nonelastic cross sections, angle-energy correlated production spectra for light ejectiles with A{le}and kinetic energies given to light ejectiles and heavy recoil fragments. The major steps involved in this effort are: (1) development and validation of nuclear models for incident energies up to 100 MeV; (2) collation of experimental measurements, including new results from Louvain-la-Nueve and Los Alamos; (3) extension of the Livermore ENDL formats for representing high-energy data; (4) calculation and evaluation of nuclear data; and (5) validation of the libraries. We describe the evaluations in detail, with particular emphasis on our new high-energy modeling developments. Our evaluations agree well with experimental measurements of integrated and differential cross sections. We compare our results with the recent ENDF/B-VI evaluation which extends up to 32 MeV.

  6. Epithermal Neutrons, Illumination, Spatial Scale and Topography: A Correlative Analysis of Factors Influencing the Detection of Slope Hydration Using LRO's Lunar Exploration Neutron Detector

    NASA Astrophysics Data System (ADS)

    McClanahan, T. P.; Mitrofanov, I. G.; Boynton, W. V.; Chin, G.; Evans, L. G.; Starr, R. D.; Livengood, T.; Sagdeev, R.; Parsons, A. M.; Su, J. J.; Murray, J.; Sanin, A.; Litvak, M.; Harshman, K.; Hamara, D.; Bodnarik, J.

    2014-10-01

    This research correlates the Moon’s south polar epithermal neutron flux, topography and a visible illumination model and shows that there is a widespread hydration of polward-facing (PF) slopes that is occurring at a continuum of spatial scales.

  7. Psychosocial Factors Influencing Calcium Intake and Bone Quality in Middle-School Girls

    PubMed Central

    Hoelscher, Deanna M.; Kelder, Steven H.; Diamond, Pamela; Day, R. Sue; Hergenroeder, Albert

    2015-01-01

    Calcium intake has been associated with promoting bone health in children and adolescents, thus, preventing osteoporosis later in life. Behavior change such as increased calcium intake, as well as physiological factors such as bone quality, may be facilitated by psychosocial and environmental factors. The purpose of this study was to identify pathways by which psychosocial factors influence calcium intake and bone quality in middle-school girls. The study design was cross-sectional. Baseline data from the Incorporating More Physical Activity and Calcium in Teens (IMPACT) study, collected in 2001–2003, were utilized. IMPACT, was a 1 ½ years nutrition and physical activity intervention study, designed to improve bone density in 717 middle-school girls in Texas. Main outcome measures were: 1) calcium intake determined using mean milligrams of calcium consumed per day and number of glasses of milk consumed per day, and 2) bone quality determined using calcaneal stiffness index. Confirmatory factor analysis and path analysis were performed to identify the direct and indirect pathways used by various psychosocial factors such as knowledge, self-efficacy, outcome expectations and milk availability at home, to influence calcium intake and bone quality. Results showed that knowledge of osteoporosis and calcium rich foods had an indirect effect on calcium intake, with outcome expectations as the mediating variable (β=0.035 and β=0.03 respectively, p < 0.05). Calcium self-efficacy had a significant indirect effect on calcium intake, with outcome expectations as the mediator (β=0.085, p < 0.05). None of the variables significantly influenced bone quality. Thus, several direct and indirect pathways used to influence calcium intake among adolescent girls, were identified. These findings are critical for the development of effective interventions to promote calcium intake in this population. PMID:20497785

  8. Identification and Assessment of Potential Water Quality Impact Factors for Drinking-Water Reservoirs

    PubMed Central

    Gu, Qing; Deng, Jinsong; Wang, Ke; Lin, Yi; Li, Jun; Gan, Muye; Ma, Ligang; Hong, Yang

    2014-01-01

    Various reservoirs have been serving as the most important drinking water sources in Zhejiang Province, China, due to the uneven distribution of precipitation and severe river pollution. Unfortunately, rapid urbanization and industrialization have been continuously challenging the water quality of the drinking-water reservoirs. The identification and assessment of potential impacts is indispensable in water resource management and protection. This study investigates the drinking water reservoirs in Zhejiang Province to better understand the potential impact on water quality. Altogether seventy-three typical drinking reservoirs in Zhejiang Province encompassing various water storage levels were selected and evaluated. Using fifty-two reservoirs as training samples, the classification and regression tree (CART) method and sixteen comprehensive variables, including six sub-sets (land use, population, socio-economy, geographical features, inherent characteristics, and climate), were adopted to establish a decision-making model for identifying and assessing their potential impacts on drinking-water quality. The water quality class of the remaining twenty-one reservoirs was then predicted and tested based on the decision-making model, resulting in a water quality class attribution accuracy of 81.0%. Based on the decision rules and quantitative importance of the independent variables, industrial emissions was identified as the most important factor influencing the water quality of reservoirs; land use and human habitation also had a substantial impact on water quality. The results of this study provide insights into the factors impacting the water quality of reservoirs as well as basic information for protecting reservoir water resources. PMID:24919129

  9. Hearing the patient's voice? Factors affecting the use of patient survey data in quality improvement

    PubMed Central

    Davies, E; Cleary, P

    2005-01-01

    Objective: To develop a framework for understanding factors affecting the use of patient survey data in quality improvement. Design: Qualitative interviews with senior health professionals and managers and a review of the literature. Setting: A quality improvement collaborative in Minnesota, USA involving teams from eight medical groups, focusing on how to use patient survey data to improve patient centred care. Participants: Eight team leaders (medical, clinical improvement or service quality directors) and six team members (clinical improvement coordinators and managers). Results: Respondents reported three types of barriers before the collaborative: organisational, professional and data related. Organisational barriers included lack of supporting values for patient centred care, competing priorities, and lack of an effective quality improvement infrastructure. Professional barriers included clinicians and staff not being used to focusing on patient interaction as a quality issue, individuals not necessarily having been selected, trained or supported to provide patient centred care, and scepticism, defensiveness or resistance to change following feedback. Data related barriers included lack of expertise with survey data, lack of timely and specific results, uncertainty over the effective interventions or time frames for improvement, and consequent risk of perceived low cost effectiveness of data collection. Factors that appeared to have promoted data use included board led strategies to change culture and create quality improvement forums, leadership from senior physicians and managers, and the persistence of quality improvement staff over several years in demonstrating change in other areas. Conclusion: Using patient survey data may require a more concerted effort than for other clinical data. Organisations may need to develop cultures that support patient centred care, quality improvement capacity, and to align professional receptiveness and leadership with

  10. Hydrological factors behind the water quality changes due to restoration in boreal peatlands

    NASA Astrophysics Data System (ADS)

    Ronkanen, Anna-Kaisa; Marttila, Hannu; Walle Menberu, Meseret; Irannezhad, Masoud; Tahvanainen, Teemu; Penttinen, Jouni; Hokkanen, Reijo; Klöve, Björn

    2016-04-01

    Recovery of hydrological conditions after restoration in previously drained peatlands is typically faster process compared to changes in runoff water quality. Often nutrient load from restored sites increase remarkably during restoration operation and reduce over time when conditions stabilize. However, in some sites nutrient load can remain high for long periods of time which increase negative effects of restoration on downstream water bodies. The factors and challenges behind these processes are poorly understood in practical catchment restoration planning. This study aims to understand factors affecting water quality changes after peatland restoration. Totally 43 peatlands areas of which 24 sites were previously drained and restored during the study and 19 sites at their pristine stage (control sites) were included to the study. The control pristine sites had as little anthropogenic disturbances as possible and the sites were chosen so that the paired study sites closely share similar peatland type, nutrient status and weather conditions. Pore water quality (total phosphorus, total nitrogen, dissolved organic carbon, pH, electric conductivity and colour) was measured from all sites and runoff quality and amount from 7 sites in the years 2008-2014. Measured parameters, different peatland types and nutrient loads were studied together with numerous hydrological parameters (variation in water table fluctuations, peat pore water recharge coefficient, physical parameters of peat e.g. specific yield, degree of humification) by statistical methods. Differences in water table dependent hydrological conditions indicate e.g. flow paths and residence time of water that is known to have effect on runoff water quality. As a result, water table related hydrological changes following restoration are as well assumed to explain alterations in water quality in different peatland types. In addition, using water table related hydrological processes as a proxy for water quality