DOE Office of Scientific and Technical Information (OSTI.GOV)
Bhandari, Churna; van Schilfgaarde, Mark; Kotani, Takao
The electronic band structure of SrTiO3 is investigated in the all-electron quasiparticle self-consistent GW (QSGW) approximation. Unlike previous pseudopotential-based QSGW or single-shot G0W0 calculations, the gap is found to be significantly overestimated compared to experiment. After putting in a correction for the underestimate of the screening by the random phase approximation in terms of a 0.8Σ approach, the gap is still overestimated. The 0.8Σ approach is discussed and justified in terms of various recent literature results including electron-hole corrections. Adding a lattice polarization correction (LPC) in the q→0 limit for the screening of W, agreement with experiment is recovered. Themore » LPC is alternatively estimated using a polaron model. Here, we apply our approach to the cubic and tetragonal phases as well as a hypothetical layered postperovskite structure and find that the local density approximation (LDA) to GW gap correction is almost independent of structure.« less
Bhandari, Churna; van Schilfgaarde, Mark; Kotani, Takao; ...
2018-01-23
The electronic band structure of SrTiO3 is investigated in the all-electron quasiparticle self-consistent GW (QSGW) approximation. Unlike previous pseudopotential-based QSGW or single-shot G0W0 calculations, the gap is found to be significantly overestimated compared to experiment. After putting in a correction for the underestimate of the screening by the random phase approximation in terms of a 0.8Σ approach, the gap is still overestimated. The 0.8Σ approach is discussed and justified in terms of various recent literature results including electron-hole corrections. Adding a lattice polarization correction (LPC) in the q→0 limit for the screening of W, agreement with experiment is recovered. Themore » LPC is alternatively estimated using a polaron model. Here, we apply our approach to the cubic and tetragonal phases as well as a hypothetical layered postperovskite structure and find that the local density approximation (LDA) to GW gap correction is almost independent of structure.« less
Structure of physical crystalline membranes within the self-consistent screening approximation.
Gazit, Doron
2009-10-01
The anomalous exponents governing the long-wavelength behavior of the flat phase of physical crystalline membranes are calculated within a self-consistent screening approximation (SCSA) applied to second order expansion in 1/dC ( dC is the codimension), extending the seminal work of Le Doussal and Radzihovsky [Phys. Rev. Lett. 69, 1209 (1992)]. In particular, the bending rigidity is found to harden algebraically in the long-wavelength limit with an exponent eta=0.789... , which is used to extract the elasticity softening exponent eta(u)=0.422... , and the roughness exponent zeta=0.605... . The scaling relation eta(u)=2-2eta is proven to hold to all orders in SCSA. Further, applying the SCSA to an expansion in 1/dC , is found to be essential, as no solution to the self-consistent equations is found in a two-bubble level, which is the naive second-order expansion. Surprisingly, even though the expansion parameter for physical membrane is 1/dC=1 , the SCSA applied to second-order expansion deviates only slightly from the first order, increasing zeta by mere 0.016. This supports the high quality of the SCSA for physical crystalline membranes, as well as improves the comparison to experiments and numerical simulations of these systems. The prediction of SCSA applied to first order expansion for the Poisson ratio is shown to be exact to all orders.
NASA Astrophysics Data System (ADS)
Stefanucci, G.; Pavlyukh, Y.; Uimonen, A.-M.; van Leeuwen, R.
2014-09-01
We present a diagrammatic approach to construct self-energy approximations within many-body perturbation theory with positive spectral properties. The method cures the problem of negative spectral functions which arises from a straightforward inclusion of vertex diagrams beyond the GW approximation. Our approach consists of a two-step procedure: We first express the approximate many-body self-energy as a product of half-diagrams and then identify the minimal number of half-diagrams to add in order to form a perfect square. The resulting self-energy is an unconventional sum of self-energy diagrams in which the internal lines of half a diagram are time-ordered Green's functions, whereas those of the other half are anti-time-ordered Green's functions, and the lines joining the two halves are either lesser or greater Green's functions. The theory is developed using noninteracting Green's functions and subsequently extended to self-consistent Green's functions. Issues related to the conserving properties of diagrammatic approximations with positive spectral functions are also addressed. As a major application of the formalism we derive the minimal set of additional diagrams to make positive the spectral function of the GW approximation with lowest-order vertex corrections and screened interactions. The method is then applied to vertex corrections in the three-dimensional homogeneous electron gas by using a combination of analytical frequency integrations and numerical Monte Carlo momentum integrations to evaluate the diagrams.
Communication: A difference density picture for the self-consistent field ansatz.
Parrish, Robert M; Liu, Fang; Martínez, Todd J
2016-04-07
We formulate self-consistent field (SCF) theory in terms of an interaction picture where the working variable is the difference density matrix between the true system and a corresponding superposition of atomic densities. As the difference density matrix directly represents the electronic deformations inherent in chemical bonding, this "difference self-consistent field (dSCF)" picture provides a number of significant conceptual and computational advantages. We show that this allows for a stable and efficient dSCF iterative procedure with wholly single-precision Coulomb and exchange matrix builds. We also show that the dSCF iterative procedure can be performed with aggressive screening of the pair space. These approximations are tested and found to be accurate for systems with up to 1860 atoms and >10 000 basis functions, providing for immediate overall speedups of up to 70% in the heavily optimized TeraChem SCF implementation.
Communication: A difference density picture for the self-consistent field ansatz
NASA Astrophysics Data System (ADS)
Parrish, Robert M.; Liu, Fang; Martínez, Todd J.
2016-04-01
We formulate self-consistent field (SCF) theory in terms of an interaction picture where the working variable is the difference density matrix between the true system and a corresponding superposition of atomic densities. As the difference density matrix directly represents the electronic deformations inherent in chemical bonding, this "difference self-consistent field (dSCF)" picture provides a number of significant conceptual and computational advantages. We show that this allows for a stable and efficient dSCF iterative procedure with wholly single-precision Coulomb and exchange matrix builds. We also show that the dSCF iterative procedure can be performed with aggressive screening of the pair space. These approximations are tested and found to be accurate for systems with up to 1860 atoms and >10 000 basis functions, providing for immediate overall speedups of up to 70% in the heavily optimized TeraChem SCF implementation.
ICANT, a code for the self-consistent computation of ICRH antenna coupling
NASA Astrophysics Data System (ADS)
Pécoul, S.; Heuraux, S.; Koch, R.; Leclert, G.
1996-02-01
The code deals with 3D antenna structures (finite length antennae) that are used to launch electromagnetic waves into tokamak plasmas. The antenna radiation problem is solved using a finite boundary element technique combined with a spectral solution of the interior problem. The slab approximation is used, and periodicity in y and z directions is introduced to account for toroidal geometry. We present results for various types of antennae radiating in vacuum: antenna with a finite Faraday screen and ideal Faraday screen, antenna with side limiters and phased antenna arrays. The results (radiated power, current profile) obtained are very close to analytical solutions when available.
Photons in dense nuclear matter: Random-phase approximation
NASA Astrophysics Data System (ADS)
Stetina, Stephan; Rrapaj, Ermal; Reddy, Sanjay
2018-04-01
We present a comprehensive and pedagogic discussion of the properties of photons in cold and dense nuclear matter based on the resummed one-loop photon self-energy. Correlations among electrons, muons, protons, and neutrons in β equilibrium that arise as a result of electromagnetic and strong interactions are consistently taken into account within the random phase approximation. Screening effects, damping, and collective excitations are systematically studied in a fully relativistic setup. Our study is relevant to the linear response theory of dense nuclear matter, calculations of transport properties of cold dense matter, and investigations of the production and propagation of hypothetical vector bosons such as the dark photons.
REVIEW ARTICLE: On correlation effects in electron spectroscopies and the GW approximation
NASA Astrophysics Data System (ADS)
Hedin, Lars
1999-10-01
The GW approximation (GWA) extends the well-known Hartree-Fock approximation (HFA) for the self-energy (exchange potential), by replacing the bare Coulomb potential v by the dynamically screened potential W, e.g. Vex = iGv is replaced by icons/Journals/Common/Sigma" ALT="Sigma" ALIGN="TOP"/>GW = iGW. Here G is the one-electron Green's function. The GWA like the HFA is self-consistent, which allows for solutions beyond perturbation theory, like say spin-density waves. In a first approximation, iGW is a sum of a statically screened exchange potential plus a Coulomb hole (equal to the electrostatic energy associated with the charge pushed away around a given electron). The Coulomb hole part is larger in magnitude, but the two parts give comparable contributions to the dispersion of the quasi-particle energy. The GWA can be said to describe an electronic polaron (an electron surrounded by an electronic polarization cloud), which has great similarities to the ordinary polaron (an electron surrounded by a cloud of phonons). The dynamical screening adds new crucial features beyond the HFA. With the GWA not only bandstructures but also spectral functions can be calculated, as well as charge densities, momentum distributions, and total energies. We will discuss the ideas behind the GWA, and generalizations which are necessary to improve on the rather poor GWA satellite structures in the spectral functions. We will further extend the GWA approach to fully describe spectroscopies like photoemission, x-ray absorption, and electron scattering. Finally we will comment on the relation between the GWA and theories for strongly correlated electronic systems. In collecting the material for this review, a number of new results and perspectives became apparent, which have not been published elsewhere.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wen, Xiaodong; Martin, Richard L.; Roy, Lindsay E.
2012-10-21
We present a systematic comparison of the lattice structures, electronic density of states, and band gaps of actinide dioxides, AnO₂ (An=Th, Pa, U, Np, Pu, and Am) predicted by the Heyd-Scuseria-Ernzerhof screened hybrid density functional (HSE) with the self-consistent inclusion of spin-orbit coupling(SOC). The computed HSE lattice constants and band gaps of AnO₂ are in consistently good agreement with the available experimental data across the series, and differ little from earlier HSE results without SOC. ThO₂ is a simple band insulator (f⁰), while PaO₂, UO₂, and NpO₂ are predicted to be Mott insulators. The remainders (PuO₂ and AmO₂) show considerablemore » O2p/An5f mixing and are classified as charge-transfer insulators. We also compare our results for UO₂, NpO₂, and PuO₂with the PBE+U, self interaction correction (SIC), and dynamic mean-field theory (DMFT) many-body approximations.« less
Self-consistent pseudopotential calculation of the bulk properties of Mo and W
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zunger, A.; Cohen, M.L.
The bulk properties of Mo and W are calculated using the recently developed momentum-space approach for calculating total energy via a nonlocal pseudopotential. This approach avoids any shape approximation to the variational charge density (e.g., muffin tins), is fully self-consistent, and replaces the multidimensional and multicenter integrals akin to real-space representations by simple and readily convergent reciprocal-space lattice sums. We use first-principles atomic pseudopotentials which have been previously demonstrated to yield band structures and charge densities for both semiconductors and transition metals in good agreement with experiment and all-electron calculations. Using a mixed-basis representation for the crystalline wave function, wemore » are able to accurately reproduce both the localized and itinerant features of the electronic states in these systems. These first-principles pseudopotentials, together with the self-consistent density-functional representation for both the exchange and the correlation screening, yields agreement with experiment of 0.2% in the lattice parameters, 2% and 11% for the binding energies of Mo and W, respectively, and 12% and 7% for the bulk moduli of Mo and W, respectively.« less
Internal Consistency Reliability of the Self-Report Antisocial Process Screening Device
ERIC Educational Resources Information Center
Poythress, Norman G.; Douglas, Kevin S.; Falkenbach, Diana; Cruise, Keith; Lee, Zina; Murrie, Daniel C.; Vitacco, Michael
2006-01-01
The self-report version of the Antisocial Process Screening Device (APSD) has become a popular measure for assessing psychopathic features in justice-involved adolescents. However, the internal consistency reliability of its component scales (Narcissism, Callous-Unemotional, and Impulsivity) has been questioned in several studies. This study…
Kutepov, A. L.
2015-07-22
Self-consistent solutions of Hedin's equations (HE) for the two-site Hubbard model (HM) have been studied. They have been found for three-point vertices of increasing complexity (Γ = 1 (GW approximation), Γ₁ from the first-order perturbation theory, and the exact vertex Γ E). Comparison is made between the cases when an additional quasiparticle (QP) approximation for Green's functions is applied during the self-consistent iterative solving of HE and when QP approximation is not applied. Results obtained with the exact vertex are directly related to the present open question—which approximation is more advantageous for future implementations, GW + DMFT or QPGW +more » DMFT. It is shown that in a regime of strong correlations only the originally proposed GW + DMFT scheme is able to provide reliable results. Vertex corrections based on Perturbation Theory systematically improve the GW results when full self-consistency is applied. The application of QP self-consistency combined with PT vertex corrections shows similar problems to the case when the exact vertex is applied combined with QP sc. An analysis of Ward Identity violation is performed for all studied in this work's approximations and its relation to the general accuracy of the schemes used is provided.« less
Kutepov, A L
2015-08-12
Self-consistent solutions of Hedin's equations (HE) for the two-site Hubbard model (HM) have been studied. They have been found for three-point vertices of increasing complexity (Γ = 1 (GW approximation), Γ1 from the first-order perturbation theory, and the exact vertex Γ(E)). Comparison is made between the cases when an additional quasiparticle (QP) approximation for Green's functions is applied during the self-consistent iterative solving of HE and when QP approximation is not applied. The results obtained with the exact vertex are directly related to the present open question-which approximation is more advantageous for future implementations, GW + DMFT or QPGW + DMFT. It is shown that in a regime of strong correlations only the originally proposed GW + DMFT scheme is able to provide reliable results. Vertex corrections based on perturbation theory (PT) systematically improve the GW results when full self-consistency is applied. The application of QP self-consistency combined with PT vertex corrections shows similar problems to the case when the exact vertex is applied combined with QP sc. An analysis of Ward Identity violation is performed for all studied in this work's approximations and its relation to the general accuracy of the schemes used is provided.
ICANT, a code for the self-consistent computation of ICRH antenna coupling
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pecoul, S.; Heuraux, S.; Koch, R.
1996-02-01
The code deals with 3D antenna structures (finite length antennae) that are used to launch electromagnetic waves into tokamak plasmas. The antenna radiation problem is solved using a finite boundary element technique combined with a spectral solution of the interior problem. The slab approximation is used, and periodicity in {ital y} and {ital z} directions is introduced to account for toroidal geometry. We present results for various types of antennae radiating in vacuum: antenna with a finite Faraday screen and ideal Faraday screen, antenna with side limiters and phased antenna arrays. The results (radiated power, current profile) obtained are verymore » close to analytical solutions when available. {copyright} {ital 1996 American Institute of Physics.}« less
Performance and Self-Consistency of the Generalized Dielectric Dependent Hybrid Functional
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brawand, Nicholas P.; Govoni, Marco; Vörös, Márton
Here, we analyze the performance of the recently proposed screened exchange constant functional (SX) on the GW100 test set, and we discuss results obtained at different levels of self-consistency. The SX functional is a generalization of dielectric dependent hybrid functionals to finite systems; it is nonempirical and depends on the average screening of the exchange interaction. We compare results for ionization potentials obtained with SX to those of CCSD(T) calculations and experiments, and we find excellent agreement, on par with recent state of the art methods based on many body perturbation theory. Applying SX perturbatively to correct PBE eigenvalues yieldsmore » improved results in most cases, except for ionic molecules, for which wave function self-consistency is instead crucial. Calculations where wave functions and the screened exchange constant (α SX) are determined self-consistently, and those where α SX is fixed to the value determined within PBE, yield results of comparable accuracy. Perturbative G 0W 0 corrections of eigenvalues obtained with self-consistent αSX are small on average, for all molecules in the GW100 test set.« less
Performance and Self-Consistency of the Generalized Dielectric Dependent Hybrid Functional
Brawand, Nicholas P.; Govoni, Marco; Vörös, Márton; ...
2017-05-24
Here, we analyze the performance of the recently proposed screened exchange constant functional (SX) on the GW100 test set, and we discuss results obtained at different levels of self-consistency. The SX functional is a generalization of dielectric dependent hybrid functionals to finite systems; it is nonempirical and depends on the average screening of the exchange interaction. We compare results for ionization potentials obtained with SX to those of CCSD(T) calculations and experiments, and we find excellent agreement, on par with recent state of the art methods based on many body perturbation theory. Applying SX perturbatively to correct PBE eigenvalues yieldsmore » improved results in most cases, except for ionic molecules, for which wave function self-consistency is instead crucial. Calculations where wave functions and the screened exchange constant (α SX) are determined self-consistently, and those where α SX is fixed to the value determined within PBE, yield results of comparable accuracy. Perturbative G 0W 0 corrections of eigenvalues obtained with self-consistent αSX are small on average, for all molecules in the GW100 test set.« less
Scale-Up of an Human Papillomavirus Testing Implementation Program in El Salvador.
Cremer, Miriam; Maza, Mauricio; Alfaro, Karla; Morales Velado, Mario; Felix, Juan; Castle, Philip E; Kim, Jane; Gage, Julia C
2017-01-01
The Cervical Cancer Prevention in El Salvador is a demonstration project to introduce a lower-cost human papillomavirus (HPV)-DNA test into a public sector project. Started in October 2012, The Cervical Cancer Prevention in El Salvador consists of 3 phases and will ultimately screen 30,000 women. Results of phase 2 of the project are presented. The objective of this project was to compare colposcopy and noncolposcopy-based management for HPV-positive women. In phase 2, a total of 8,050 women, aged 30 to 49 years, were screened; 6,761 provided both self- and provider-collected specimens and 1,289 provided only provider-testing specimens. HPV results from self-collected specimens were not used in clinical management decisions. Women with provider-collected HPV-positive results were treated based on the strategy assigned to their community; the strategy was colposcopy management (CM) or screen-and-treat (ST) management if they were cryotherapy eligible or colposcopy if not eligible. Outcomes were assessed 6 months after screening. Overall, 489 (12.3%) of 3,963 women receiving CM and 465 (11.4%) of 4,087 women receiving ST tested HPV positive. In the CM cohort, 216 (44.2%) of 489 completed their intervention (203 treated, 11 diagnosed negative, 2 pregnant). In the ST cohort, 411 (88.4%) of 465 completed their intervention (407 treated, 2 diagnosed negative, 1 pregnant). Overall agreement between HPV test results from self-collected and provider-collected specimens was 93.7%, with a κ value of 0.70 (95% CI = 0.68-0.73). Human papillomavirus testing with ST management resulted in an approximately twice completion rate compared with CM management. Agreement between self- and provider-based sampling was good and might be used to extend screening to women in areas that are more difficult to reach.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Parrish, Robert M.; Liu, Fang; Martínez, Todd J., E-mail: toddjmartinez@gmail.com
We formulate self-consistent field (SCF) theory in terms of an interaction picture where the working variable is the difference density matrix between the true system and a corresponding superposition of atomic densities. As the difference density matrix directly represents the electronic deformations inherent in chemical bonding, this “difference self-consistent field (dSCF)” picture provides a number of significant conceptual and computational advantages. We show that this allows for a stable and efficient dSCF iterative procedure with wholly single-precision Coulomb and exchange matrix builds. We also show that the dSCF iterative procedure can be performed with aggressive screening of the pair space.more » These approximations are tested and found to be accurate for systems with up to 1860 atoms and >10 000 basis functions, providing for immediate overall speedups of up to 70% in the heavily optimized TERACHEM SCF implementation.« less
Paskett, E D; Tatum, C M; Mack, D W; Hoen, H; Case, L D; Velez, R
1996-09-01
The objective of the Forsyth County Cancer Screening Project is to assess barriers to breast and cervical cancer screening among low-income women and to develop an educational program to address these barriers. To properly assess the barriers, it was first necessary to determine if self-reported rates of breast and cervical cancer screening were accurate. All women who participated in the baseline survey (n = 555) were asked to provide information regarding if, where, and when they had obtained mammograms and Pap smears. Identified health care facilities were then contacted to verify this information. Approximately 80% of responses were verified for at least one of the exams with the information provided. For mammography, 77% of self-reports were correct, whereas 67% of self-reports of Pap smear screening were correct (kappa = 0.54 and 0.15, respectively). For both tests, women thought they had received them more recently than they actually had, by an average of 3 months for mammography and 23 months for Pap smears. Using validated reports of screening did not substantially change identified predictors of screening for mammography. For Pap smear screening, however, most of the identified predictors of screening became nonsignificant when medical chart reports were used instead of self-reports, suggesting that caution should be used in relying on self-reports to design programs to improve cervical cancer screening practices.
Arita, Ryotaro; Koretsune, Takashi; Sakai, Shiro; Akashi, Ryosuke; Nomura, Yusuke; Sano, Wataru
2017-07-01
Recent progress in the fully nonempirical calculation of the superconducting transition temperature (T c ) is reviewed. Especially, this study focuses on three representative light-element high-T c superconductors, i.e., elemental Li, sulfur hydrides, and alkali-doped fullerides. Here, it is discussed how crucial it is to develop the beyond Migdal-Eliashberg (ME) methods. For Li, a scheme of superconducting density functional theory for the plasmon mechanism is formulated and it is found that T c is dramatically enhanced by considering the frequency dependence of the screened Coulomb interaction. For sulfur hydrides, it is essential to go beyond not only the static approximation for the screened Coulomb interaction, but also the constant density-of-states approximation for electrons, the harmonic approximation for phonons, and the Migdal approximation for the electron-phonon vertex, all of which have been employed in the standard ME calculation. It is also shown that the feedback effect in the self-consistent calculation of the self-energy and the zero point motion considerably affect the calculation of T c . For alkali-doped fullerides, the interplay between electron-phonon coupling and electron correlations becomes more nontrivial. It has been demonstrated that the combination of density functional theory and dynamical mean field theory with the ab initio downfolding scheme for electron-phonon coupled systems works successfully. This study not only reproduces the experimental phase diagram but also obtains a unified view of the high-T c superconductivity and the Mott-Hubbard transition in the fullerides. The results for these high-T c superconductors will provide a firm ground for future materials design of new superconductors. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Potential of mean force for electrical conductivity of dense plasmas
DOE Office of Scientific and Technical Information (OSTI.GOV)
Starrett, C. E.
The electrical conductivity in dense plasmas can be calculated with the relaxation-time approximation provided that the interaction potential between the scattering electron and the ion is known. To date there has been considerable uncertainty as to the best way to define this interaction potential so that it correctly includes the effects of ionic structure, screening by electrons and partial ionization. The current approximations lead to significantly different results with varying levels of agreement when compared to bench-mark calculations and experiments. Here, we present a new way to define this potential, drawing on ideas from classical fluid theory to define amore » potential of mean force. This new potential results in significantly improved agreement with experiments and bench-mark calculations, and includes all the aforementioned physics self-consistently.« less
Potential of mean force for electrical conductivity of dense plasmas
Starrett, C. E.
2017-09-28
The electrical conductivity in dense plasmas can be calculated with the relaxation-time approximation provided that the interaction potential between the scattering electron and the ion is known. To date there has been considerable uncertainty as to the best way to define this interaction potential so that it correctly includes the effects of ionic structure, screening by electrons and partial ionization. The current approximations lead to significantly different results with varying levels of agreement when compared to bench-mark calculations and experiments. Here, we present a new way to define this potential, drawing on ideas from classical fluid theory to define amore » potential of mean force. This new potential results in significantly improved agreement with experiments and bench-mark calculations, and includes all the aforementioned physics self-consistently.« less
Potential of mean force for electrical conductivity of dense plasmas
NASA Astrophysics Data System (ADS)
Starrett, C. E.
2017-12-01
The electrical conductivity in dense plasmas can be calculated with the relaxation-time approximation provided that the interaction potential between the scattering electron and the ion is known. To date there has been considerable uncertainty as to the best way to define this interaction potential so that it correctly includes the effects of ionic structure, screening by electrons and partial ionization. Current approximations lead to significantly different results with varying levels of agreement when compared to bench-mark calculations and experiments. We present a new way to define this potential, drawing on ideas from classical fluid theory to define a potential of mean force. This new potential results in significantly improved agreement with experiments and bench-mark calculations, and includes all the aforementioned physics self-consistently.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Säkkinen, Niko; Leeuwen, Robert van; Peng, Yang
2015-12-21
We study ground-state properties of a two-site, two-electron Holstein model describing two molecules coupled indirectly via electron-phonon interaction by using both exact diagonalization and self-consistent diagrammatic many-body perturbation theory. The Hartree and self-consistent Born approximations used in the present work are studied at different levels of self-consistency. The governing equations are shown to exhibit multiple solutions when the electron-phonon interaction is sufficiently strong, whereas at smaller interactions, only a single solution is found. The additional solutions at larger electron-phonon couplings correspond to symmetry-broken states with inhomogeneous electron densities. A comparison to exact results indicates that this symmetry breaking is stronglymore » correlated with the formation of a bipolaron state in which the two electrons prefer to reside on the same molecule. The results further show that the Hartree and partially self-consistent Born solutions obtained by enforcing symmetry do not compare well with exact energetics, while the fully self-consistent Born approximation improves the qualitative and quantitative agreement with exact results in the same symmetric case. This together with a presented natural occupation number analysis supports the conclusion that the fully self-consistent approximation describes partially the bipolaron crossover. These results contribute to better understanding how these approximations cope with the strong localizing effect of the electron-phonon interaction.« less
NASA Astrophysics Data System (ADS)
Li, Xiayue; Curtis, Farren S.; Rose, Timothy; Schober, Christoph; Vazquez-Mayagoitia, Alvaro; Reuter, Karsten; Oberhofer, Harald; Marom, Noa
2018-06-01
We present Genarris, a Python package that performs configuration space screening for molecular crystals of rigid molecules by random sampling with physical constraints. For fast energy evaluations, Genarris employs a Harris approximation, whereby the total density of a molecular crystal is constructed via superposition of single molecule densities. Dispersion-inclusive density functional theory is then used for the Harris density without performing a self-consistency cycle. Genarris uses machine learning for clustering, based on a relative coordinate descriptor developed specifically for molecular crystals, which is shown to be robust in identifying packing motif similarity. In addition to random structure generation, Genarris offers three workflows based on different sequences of successive clustering and selection steps: the "Rigorous" workflow is an exhaustive exploration of the potential energy landscape, the "Energy" workflow produces a set of low energy structures, and the "Diverse" workflow produces a maximally diverse set of structures. The latter is recommended for generating initial populations for genetic algorithms. Here, the implementation of Genarris is reported and its application is demonstrated for three test cases.
Electrostatic correlations in inhomogeneous charged fluids beyond loop expansion
NASA Astrophysics Data System (ADS)
Buyukdagli, Sahin; Achim, C. V.; Ala-Nissila, T.
2012-09-01
Electrostatic correlation effects in inhomogeneous symmetric electrolytes are investigated within a previously developed electrostatic self-consistent theory [R. R. Netz and H. Orland, Eur. Phys. J. E 11, 301 (2003)], 10.1140/epje/i2002-10159-0. To this aim, we introduce two computational approaches that allow to solve the self-consistent equations beyond the loop expansion. The first method is based on a perturbative Green's function technique, and the second one is an extension of a previously introduced semiclassical approximation for single dielectric interfaces to the case of slit nanopores. Both approaches can handle the case of dielectrically discontinuous boundaries where the one-loop theory is known to fail. By comparing the theoretical results obtained from these schemes with the results of the Monte Carlo simulations that we ran for ions at neutral single dielectric interfaces, we first show that the weak coupling Debye-Huckel theory remains quantitatively accurate up to the bulk ion density ρb ≃ 0.01 M, whereas the self-consistent theory exhibits a good quantitative accuracy up to ρb ≃ 0.2 M, thus improving the accuracy of the Debye-Huckel theory by one order of magnitude in ionic strength. Furthermore, we compare the predictions of the self-consistent theory with previous Monte Carlo simulation data for charged dielectric interfaces and show that the proposed approaches can also accurately handle the correlation effects induced by the surface charge in a parameter regime where the mean-field result significantly deviates from the Monte Carlo data. Then, we derive from the perturbative self-consistent scheme the one-loop theory of asymmetrically partitioned salt systems around a dielectrically homogeneous charged surface. It is shown that correlation effects originate in these systems from a competition between the salt screening loss at the interface driving the ions to the bulk region, and the interfacial counterion screening excess attracting them towards the surface. This competition can be quantified in terms of the characteristic surface charge σ _s^*=√{2ρ _b/(π ℓ _B)}, where ℓB = 7 Å is the Bjerrum length. In the case of weak surface charges σ _s≪ σ _s^* where counterions form a diffuse layer, the interfacial salt screening loss is the dominant effect. As a result, correlation effects decrease the mean-field density of both coions and counterions. With an increase of the surface charge towards σ _s^*, the surface-attractive counterion screening excess starts to dominate, and correlation effects amplify in this regime the mean-field density of both type of ions. However, in the regime σ _s>σ _s^*, the same counterion screening excess also results in a significant decrease of the electrostatic mean-field potential. This reduces in turn the mean-field counterion density far from the charged surface. We also show that for σ _s≫ σ _s^*, electrostatic correlations result in a charge inversion effect. However, the electrostatic coupling regime where this phenomenon takes place should be verified with Monte Carlo simulations since this parameter regime is located beyond the validity range of the one-loop theory.
Electrostatic correlations in inhomogeneous charged fluids beyond loop expansion.
Buyukdagli, Sahin; Achim, C V; Ala-Nissila, T
2012-09-14
Electrostatic correlation effects in inhomogeneous symmetric electrolytes are investigated within a previously developed electrostatic self-consistent theory [R. R. Netz and H. Orland, Eur. Phys. J. E 11, 301 (2003)]. To this aim, we introduce two computational approaches that allow to solve the self-consistent equations beyond the loop expansion. The first method is based on a perturbative Green's function technique, and the second one is an extension of a previously introduced semiclassical approximation for single dielectric interfaces to the case of slit nanopores. Both approaches can handle the case of dielectrically discontinuous boundaries where the one-loop theory is known to fail. By comparing the theoretical results obtained from these schemes with the results of the Monte Carlo simulations that we ran for ions at neutral single dielectric interfaces, we first show that the weak coupling Debye-Huckel theory remains quantitatively accurate up to the bulk ion density ρ(b) ≃ 0.01 M, whereas the self-consistent theory exhibits a good quantitative accuracy up to ρ(b) ≃ 0.2 M, thus improving the accuracy of the Debye-Huckel theory by one order of magnitude in ionic strength. Furthermore, we compare the predictions of the self-consistent theory with previous Monte Carlo simulation data for charged dielectric interfaces and show that the proposed approaches can also accurately handle the correlation effects induced by the surface charge in a parameter regime where the mean-field result significantly deviates from the Monte Carlo data. Then, we derive from the perturbative self-consistent scheme the one-loop theory of asymmetrically partitioned salt systems around a dielectrically homogeneous charged surface. It is shown that correlation effects originate in these systems from a competition between the salt screening loss at the interface driving the ions to the bulk region, and the interfacial counterion screening excess attracting them towards the surface. This competition can be quantified in terms of the characteristic surface charge σ(s)*=√(2ρ(b)/(πl(B)), where l(B) = 7 Å is the Bjerrum length. In the case of weak surface charges σ(s)≪σ(s)* where counterions form a diffuse layer, the interfacial salt screening loss is the dominant effect. As a result, correlation effects decrease the mean-field density of both coions and counterions. With an increase of the surface charge towards σ(s)*, the surface-attractive counterion screening excess starts to dominate, and correlation effects amplify in this regime the mean-field density of both type of ions. However, in the regime σ(s)>σ(s)*, the same counterion screening excess also results in a significant decrease of the electrostatic mean-field potential. This reduces in turn the mean-field counterion density far from the charged surface. We also show that for σ(s)≫σ(s)*, electrostatic correlations result in a charge inversion effect. However, the electrostatic coupling regime where this phenomenon takes place should be verified with Monte Carlo simulations since this parameter regime is located beyond the validity range of the one-loop theory.
Mehta, Sandhya; Mocarski, Michelle; Wisniewski, Tami; Gillespie, Karin; Narayan, K M Venkat; Lang, Kathleen
2017-01-01
To assess primary care physicians' (PCPs) knowledge of type 2 diabetes screening guidelines (American Diabetes Association (ADA) and 2008 US Preventive Services Task Force (USPSTF)), the alignment between their self-reported adherence and actual practice, and how often PCPs recommended diabetes prevention and self-management education programs (DPP/DSME). An online survey of PCPs to understand knowledge and adherence toward use of USPSTF/ADA guidelines and recommendation of DPP/DSME. Patient data from electronic medical records (EMRs) for each PCP were used to identify rates of screening in eligible patients as per guidelines and the two sources were compared to assess concordance. Of 305 surveyed physicians, 38% reported use of both guidelines (33% use ADA only, 25% USPSTF only). Approximately one-third of physicians who reported use of USPSTF/ADA guidelines had non-concordant EMR data. Similarly, while most PCPs reported they are 'very likely' to screen patients with risk factors listed in guidelines, for each criterion at least one-fourth (24%) of PCPs survey responses were non-concordant with EMRs. PCPs reported they provide referral to DPP and DSME on average to 45% and 67% of their newly diagnosed patients with pre-diabetes and diabetes, respectively. Findings show disconnect between PCPs' perceptions of adherence to screening guidelines and actual practice, and highlight limited referrals to DPP/DSME programs. More research is needed to understand barriers to guideline consistent screening and uptake of DPP/DSME, particularly in light of recent policy changes such as the linking USPSTF criteria to reimbursement and expected Medicare DPP reimbursement in 2018.
Scale-Up of an Human Papillomavirus Testing Implementation Program in El Salvador
Cremer, Miriam; Maza, Mauricio; Alfaro, Karla; Morales Velado, Mario; Felix, Juan; Castle, Philip E.; Kim, Jane; Gage, Julia C.
2017-01-01
Objective The Cervical Cancer Prevention in El Salvador is a demonstration project to introduce a lower-cost human papillomavirus (HPV)-DNA test into a public sector project. Started in October 2012, The Cervical Cancer Prevention in El Salvador consists of 3 phases and will ultimately screen 30,000 women. Results of phase 2 of the project are presented. The objective of this project was to compare colposcopy and noncolposcopy-based management for HPV-positive women. Material and Methods In phase 2, a total of 8,050 women, aged 30 to 49 years, were screened; 6,761 provided both self- and provider-collected specimens and 1,289 provided only provider-testing specimens. HPV results from self-collected specimens were not used in clinical management decisions. Women with provider-collected HPV-positive results were treated based on the strategy assigned to their community; the strategy was colposcopy management (CM) or screen-and-treat (ST) management if they were cryotherapy eligible or colposcopy if not eligible. Outcomes were assessed 6 months after screening. Results Overall, 489 (12.3%) of 3,963 women receiving CM and 465 (11.4%) of 4,087 women receiving ST tested HPV positive. In the CM cohort, 216 (44.2%) of 489 completed their intervention (203 treated, 11 diagnosed negative, 2 pregnant). In the ST cohort, 411 (88.4%) of 465 completed their intervention (407 treated, 2 diagnosed negative, 1 pregnant). Overall agreement between HPV test results from self-collected and provider-collected specimens was 93.7%, with a κ value of 0.70 (95% CI = 0.68–0.73). Conclusions Human papillomavirus testing with ST management resulted in an approximately twice completion rate compared with CM management. Agreement between self- and provider-based sampling was good and might be used to extend screening to women in areas that are more difficult to reach. PMID:27922905
Self-consistent approximation beyond the CPA: Part II
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kaplan, T.; Gray, L.J.
1981-08-01
In Part I, Professor Leath has described the substantial efforts to generalize the CPA. In this second part, a particular self-consistent approximation for random alloys developed by Kaplan, Leath, Gray, and Diehl is described. This approximation is applicable to diagonal, off-diagonal and environmental disorder, includes cluster scattering, and yields a translationally invariant and analytic (Herglotz) average Green's function. Furthermore Gray and Kaplan have shown that an approximation for alloys with short-range order can be constructed from this theory.
NASA Astrophysics Data System (ADS)
Pécoul, S.; Heuraux, S.; Koch, R.; Leclert, G.
2002-07-01
A realistic modeling of ICRH antennas requires the knowledge of the antenna currents. The code ICANT determines self-consistently these currents and, as a byproduct, the electrical characteristics of the antenna (radiated power, propagation constants on straps, frequency response, … ). The formalism allows for the description of three-dimensional antenna elements (for instance, finite size thick screen blades). The results obtained for various cases where analytical results are available are discussed. The resonances appearing in the spectrum and the occurrence of unphysical resonant modes are discussed. The capability of this self-consistent method is illustrated by a number of examples, e.g., fully conducting thin or thick screen bars leading to magnetic shielding effects, frequency response and resonances of an end-tuned antenna, field distributions in front of a Tore-Supra type antenna with tilted screen blades.
A self-consistent treatment of a fluid in an external potential
NASA Astrophysics Data System (ADS)
Boudh-Hir, M.-E.
A simple fluid of particles near a repulsive structureless wall can be approximated by an identical fluid interacting with an ideal wall. The expansion in powers of the Andersen-Weeks-Chandler (AWC) blip function is used. Lado's criterion, which permits a self-consistent approximation, is extended to the surface case.
Lockhart, Alexandre; Psioda, Matt; Ting, Jie; Campbell, Sara; Mugo, Nelly; Kwatampora, Jessie; Chitwa, Michael; Kimani, Joshua; Gakure, Anne; Smith, Jennifer S
2018-01-02
To examine the agreement between sexually transmitted infection (STI) screening using self-collected specimens and physician-collected specimens, and to investigate the acceptability of self-collection for screening in an 18-month study of female sex-workers (FSW) in a high-risk, low-resource setting. A total of 350 FSW in Nairobi, Kenya participated in a prospective study from 2009-2011. Women self-collected a cervico-vaginal specimen. Next, a physician conducted a pelvic examination to obtain a cervical specimen. Physician- and self-collected specimens were tested for Chlamydia trachomatis (CT), Neisseria gonorrhoeae (GC), Trichomonas vaginalis (TV) and Mycoplasma genitalium (MG) using Aptima nucleic acid amplification assays (Hologic). Specimens were collected at three-month intervals over 18-months follow-up. Kappa statistics measured agreement of positivity between self- and physician-collection. Baseline STI prevalence was 2.9% for GC, 5.2% for CT, 9.2% for TV, and 20.1% for MG in self-collected samples, and 2.3%, 3.7%, 7.2%, and 12.9% respectively in physician-collected samples. Kappa agreement was consistently strong (range 0.66-1.00) for all STIs over the 18-month study period, except MG which had moderate agreement (range: 0.50-0.75). Most participants found self-collection easy (94%) and comfortable (89%) at baseline, with responses becoming modestly more favorable over time. Self-collected specimens screening results showed strong agreement to clinical-collected specimens, except MG which was consistently detected more commonly in self- than physician-collected specimens. Acceptability of the self-collection procedure was high at baseline and increased modestly over time. In high-risk, low-resource settings, STI screening with self-collected specimens provides a reliable and acceptable alternative to screening with physician-collected specimens.
Excitation of propagating magnetization waves by microstrip antennas
NASA Astrophysics Data System (ADS)
Dmitriev, V. F.; Kalinikos, B. A.
1988-11-01
We discuss the self-consistent theory of excitation of dipole-exchange magnetization waves by microstrip antennas in a metal-dielectric-ferrite-dielectric-metal stratified structure, magnetized under an arbitrary angle to the surface. Spin-wave Green's functions are derived, describing the response of the spin-system to a spatially inhomogeneous varying magnetic field. The radiative resistance of microstrip antenna is calculated. In this case the distribution of surface current density in the antenna is found on the basis of the analytic solution of a singular integral equation. The nature of the effect of metallic screens and redistributed surface current densities in the antenna on the frequency dependence of the resistive radiation is investigated. Approximate relations are obtained, convenient for practical calculations of radiative resistance of microstrip antennas both in a free and in a screened ferromagnetic film. The theoretical calculations are verified by data of experiments carried out on monocrystalline films of iron-yttrium garnet.
Applying the Theory of Planned Behavior to Explain Women's Role in Prostate Cancer Screening.
Di Sarra, Luca; Ghezzi, Valerio; Eastland, Taryn Yolanda; Antonini, Francesca; Scialó, Gennaro; Zega, Maurizio; Alvaro, Rosaria
2015-01-01
To test the suitability of the theory of planned behavior (TPB) for explaining Italian women's role in prostatic cancer screening promotion. A descriptive, cross-sectional, online self-report survey was conducted with a convenience sample of 235 Italian women. Variables included attitudes women's role, perceived behavioral control, subjective norm, behavioral intention, and prostate cancer screening promotion behavior. A survey composed of the Eastland Prostate Cancer Survey subscales that were consistent with the TPB was distributed via e-mail to potential participants. The survey was live for 12 weeks (March 2013 to May 2013). Responses were collated with eSurv.org. Data were analyzed using latent path analysis and structural equation modeling. Behavioral intentions in promoting prostate cancer screening significantly predicted the likelihood of the Italian women to adopt self-reported prostate cancer screening promotion behaviors. In addition, the exclusive direct impact of the intentions explained 39% of the variance in self-reported behaviors. The TPB could represent a good framework to explain the role of Italian women in prevention behaviors related to the prostatic screening domain. Consistent with literature findings in social and nursing sciences, the intention to promote prostate cancer screening was a powerful "predictor" of the behavior itself.
Quasiparticle self-consistent GW method for the spectral properties of complex materials.
Bruneval, Fabien; Gatti, Matteo
2014-01-01
The GW approximation to the formally exact many-body perturbation theory has been applied successfully to materials for several decades. Since the practical calculations are extremely cumbersome, the GW self-energy is most commonly evaluated using a first-order perturbative approach: This is the so-called G 0 W 0 scheme. However, the G 0 W 0 approximation depends heavily on the mean-field theory that is employed as a basis for the perturbation theory. Recently, a procedure to reach a kind of self-consistency within the GW framework has been proposed. The quasiparticle self-consistent GW (QSGW) approximation retains some positive aspects of a self-consistent approach, but circumvents the intricacies of the complete GW theory, which is inconveniently based on a non-Hermitian and dynamical self-energy. This new scheme allows one to surmount most of the flaws of the usual G 0 W 0 at a moderate calculation cost and at a reasonable implementation burden. In particular, the issues of small band gap semiconductors, of large band gap insulators, and of some transition metal oxides are then cured. The QSGW method broadens the range of materials for which the spectral properties can be predicted with confidence.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu, Fang, E-mail: fliu@lsec.cc.ac.cn; Lin, Lin, E-mail: linlin@math.berkeley.edu; Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
We present a numerical integration scheme for evaluating the convolution of a Green's function with a screened Coulomb potential on the real axis in the GW approximation of the self energy. Our scheme takes the zero broadening limit in Green's function first, replaces the numerator of the integrand with a piecewise polynomial approximation, and performs principal value integration on subintervals analytically. We give the error bound of our numerical integration scheme and show by numerical examples that it is more reliable and accurate than the standard quadrature rules such as the composite trapezoidal rule. We also discuss the benefit ofmore » using different self energy expressions to perform the numerical convolution at different frequencies.« less
Hinten, Floor; Hilbrands, Luuk B; Meeuwis, Kim A; van Bergen-Verkuyten, Muriël C; Slangen, Brigitte F; van Rossum, Michelle M; Rahamat-Langendoen, Janette; Massuger, Leon F; de Hullu, Joanne A; Melchers, Willem J
2017-01-01
Female renal transplant recipients (RTRs) have increased risk for developing human papillomavirus (HPV)-related (pre)malignancies of the lower genital tract. Annual cervical screening is advised for RTRs, but the participation rate is low. The aim of this study is to investigate whether HPV self-sampling is suitable for gynecological screening of RTRs to increase participation rate. A large cohort of 253 RTRs was investigated for the prevalence of HPV. All participants received a device for a cervicovaginal self-sample. Questionnaires were sent to assess the experience with this device. High-risk (hrHPV) presence was determined with the SPF10-LiPA25 system and GP5+/6+ PCR. HrHPV-positive patients underwent gynecological examination. More than 90% of the patients rated their experience with the self-sample device as good to excellent, and 77% preferred self-sampling over a physician taken sample. Approximately thirty-five of 217 women tested hrHPV positive with SPF10- LiPA25, and 22 tested positive with the GP5+/6+ PCR. Eleven hrHPV-positive patients had clinically relevant gynecological abnormalities, and they all tested positive with GP5+/6+ PCR. Self-sampling is clinically applicable in a gynecological screening and is preferred by female RTRs. Therefore, self-sampling could be implemented with the aim to increase the participation rate of female RTRs in yearly gynecological screening.
Stages of change in adults who have failed an online hearing screening.
Laplante-Lévesque, Ariane; Brännström, K Jonas; Ingo, Elisabeth; Andersson, Gerhard; Lunner, Thomas
2015-01-01
Hearing screening has been proposed to promote help-seeking and rehabilitation in adults with hearing impairment. However, some longitudinal studies point to low help-seeking and subsequent rehabilitation after a failed hearing screening (positive screening result). Some barriers to help-seeking and rehabilitation could be intrinsic to the profiles and needs of people who have failed a hearing screening. Theories of health behavior change could help to understand this population. One of these theories is the transtheoretical (stages-of-change) model of health behavior change, which describes profiles and needs of people facing behavior changes such as seeking help and taking up rehabilitation. According to this model, people go through distinct stages toward health behavior change: precontemplation, contemplation, action, and finally, maintenance. The present study describes the psychometric properties (construct validity) of the stages of change in adults who have failed an online hearing screening. Stages of change were measured with the University of Rhode Island Change Assessment (URICA). Principal component analysis is presented, along with cluster analysis. Internal consistency was investigated. Finally, relationships between URICA scores and speech-in-noise recognition threshold, self-reported hearing disability, and self-reported duration of hearing disability are presented. In total, 224 adults who had failed a Swedish online hearing screening test (measure of speech-in-noise recognition) completed further questionnaires online, including the URICA. A principal component analysis identified the stages of precontemplation, contemplation, and action, plus an additional stage, termed preparation (between contemplation and action). According to the URICA, half (50%) of the participants were in the preparation stage of change. The contemplation stage was represented by 38% of participants, while 9% were in the precontemplation stage. Finally, the action stage was represented by approximately 3% of the participants. Cluster analysis identified four stages-of-change clusters: they were named decision making (44% of sample), participation (28% of sample), indecision (16% of sample), and reluctance (12% of sample). The construct validity of the model was good. Participants who reported a more advanced stage of change had significantly greater self-reported hearing disability. However, participants who reported a more advanced stage of change did not have a significantly worse speech-in-noise recognition threshold or reported a significantly longer duration of hearing impairment. The additional stage this study uncovered, and which other studies have also uncovered, preparation, highlights the need for adequate guidance for adults who are yet to seek help for their hearing. The fact that very few people were in the action stage (approximately 3% of the sample) signals that screening alone is unlikely to be enough to improve help-seeking and rehabilitation rates. As expected, people in the later stages of change reported significantly greater hearing disability. The lack of significant relationships between stages-of-change measures and speech-in-noise recognition threshold and self-reported duration of hearing disability highlights the complex interplay between impairment, disability, and behaviors in adults who have failed an online hearing screening and who are yet to seek help.
NASA Astrophysics Data System (ADS)
Zahid, F.; Paulsson, M.; Polizzi, E.; Ghosh, A. W.; Siddiqui, L.; Datta, S.
2005-08-01
We present a transport model for molecular conduction involving an extended Hückel theoretical treatment of the molecular chemistry combined with a nonequilibrium Green's function treatment of quantum transport. The self-consistent potential is approximated by CNDO (complete neglect of differential overlap) method and the electrostatic effects of metallic leads (bias and image charges) are included through a three-dimensional finite element method. This allows us to capture spatial details of the electrostatic potential profile, including effects of charging, screening, and complicated electrode configurations employing only a single adjustable parameter to locate the Fermi energy. As this model is based on semiempirical methods it is computationally inexpensive and flexible compared to ab initio models, yet at the same time it is able to capture salient qualitative features as well as several relevant quantitative details of transport. We apply our model to investigate recent experimental data on alkane dithiol molecules obtained in a nanopore setup. We also present a comparison study of single molecule transistors and identify electronic properties that control their performance.
Modeling viscosity and diffusion of plasma mixtures across coupling regimes
NASA Astrophysics Data System (ADS)
Arnault, Philippe
2014-10-01
Viscosity and diffusion of plasma for pure elements and multicomponent mixtures are modeled from the high-temperature low-density weakly coupled regime to the low-temperature high-density strongly coupled regime. Thanks to an atom in jellium modeling, the effect of electron screening on the ion-ion interaction is incorporated through a self-consistent definition of the ionization. This defines an effective One Component Plasma, or an effective Binary Ionic Mixture, that is representative of the strength of the interaction. For the viscosity and the interdiffusion of mixtures, approximate kinetic expressions are supplemented by mixing laws applied to the excess viscosity and self-diffusion of pure elements. The comparisons with classical and quantum molecular dynamics results reveal deviations in the range 20--40% on average with almost no predictions further than a factor of 2 over many decades of variation. Applications in the inertial confinement fusion context could help in predicting the growth of hydrodynamic instabilities.
NASA Astrophysics Data System (ADS)
Pécoul, S.; Heuraux, S.; Koch, R.; Leclert, G.; Bécoulet, A.; Colas, L.
1999-09-01
Self-consistent calculations of the 3D electric field patterns between the screen and the plasma have been made with the ICANT code for realistic antennas. Here we explain how the ICRH antennas of the Tore Supra tokamak are modelled.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pecoul, S.; Heuraux, S.; Koch, R.
1999-09-20
Self-consistent calculations of the 3D electric field patterns between the screen and the plasma have been made with the ICANT code for realistic antennas. Here we explain how the ICRH antennas of the Tore Supra tokamak are modelled.
Enerly, Espen; Bonde, Jesper; Schee, Kristina; Pedersen, Helle; Lönnberg, Stefan; Nygård, Mari
2016-01-01
Increasing attendance to screening offers the best potential for improving the effectiveness of well-established cervical cancer screening programs. Self-sampling at home for human papillomavirus (HPV) testing as an alternative to a clinical sampling can be a useful policy to increase attendance. To determine whether self-sampling improves screening attendance for women who do not regularly attend the Norwegian Cervical Cancer Screening Programme (NCCSP), 800 women aged 25–69 years in the Oslo area who were due to receive a 2nd reminder to attend regular screening were randomly selected and invited to be part of the intervention group. Women in this group received one of two self-sampling devices, Evalyn Brush or Delphi Screener. To attend screening, women in the intervention group had the option of using the self-sampling device (self-sampling subgroup) or visiting their physician for a cervical smear. Self-sampled specimens were split and analyzed for the presence of high-risk (hr) HPV by the CLART® HPV2 test and the digene® Hybrid Capture (HC)2 test. The control group consisted of 2593 women who received a 2nd reminder letter according to the current guidelines of the NCCSP. The attendance rates were 33.4% in the intervention group and 23.2% in the control group, with similar attendance rates for both self-sampling devices. Women in the self-sampling subgroup responded favorably to both self-sampling devices and cited not remembering receiving a call for screening as the most dominant reason for previous non-attendance. Thirty-two of 34 (94.1%) hrHPV-positive women in the self-sampling subgroup attended follow-up. In conclusion, self-sampling increased attendance rates and was feasible and well received. This study lends further support to the proposal that self-sampling may be a valuable alternative for increasing cervical cancer screening coverage in Norway. PMID:27073929
Enerly, Espen; Bonde, Jesper; Schee, Kristina; Pedersen, Helle; Lönnberg, Stefan; Nygård, Mari
2016-01-01
Increasing attendance to screening offers the best potential for improving the effectiveness of well-established cervical cancer screening programs. Self-sampling at home for human papillomavirus (HPV) testing as an alternative to a clinical sampling can be a useful policy to increase attendance. To determine whether self-sampling improves screening attendance for women who do not regularly attend the Norwegian Cervical Cancer Screening Programme (NCCSP), 800 women aged 25-69 years in the Oslo area who were due to receive a 2nd reminder to attend regular screening were randomly selected and invited to be part of the intervention group. Women in this group received one of two self-sampling devices, Evalyn Brush or Delphi Screener. To attend screening, women in the intervention group had the option of using the self-sampling device (self-sampling subgroup) or visiting their physician for a cervical smear. Self-sampled specimens were split and analyzed for the presence of high-risk (hr) HPV by the CLART® HPV2 test and the digene® Hybrid Capture (HC)2 test. The control group consisted of 2593 women who received a 2nd reminder letter according to the current guidelines of the NCCSP. The attendance rates were 33.4% in the intervention group and 23.2% in the control group, with similar attendance rates for both self-sampling devices. Women in the self-sampling subgroup responded favorably to both self-sampling devices and cited not remembering receiving a call for screening as the most dominant reason for previous non-attendance. Thirty-two of 34 (94.1%) hrHPV-positive women in the self-sampling subgroup attended follow-up. In conclusion, self-sampling increased attendance rates and was feasible and well received. This study lends further support to the proposal that self-sampling may be a valuable alternative for increasing cervical cancer screening coverage in Norway.
Pyenson, Bruce S; Henschke, Claudia I; Yankelevitz, David F; Yip, Rowena; Dec, Ellynne
2014-08-01
By a wide margin, lung cancer is the most significant cause of cancer death in the United States and worldwide. The incidence of lung cancer increases with age, and Medicare beneficiaries are often at increased risk. Because of its demonstrated effectiveness in reducing mortality, lung cancer screening with low-dose computed tomography (LDCT) imaging will be covered without cost-sharing starting January 1, 2015, by nongrandfathered commercial plans. Medicare is considering coverage for lung cancer screening. To estimate the cost and cost-effectiveness (ie, cost per life-year saved) of LDCT lung cancer screening of the Medicare population at high risk for lung cancer. Medicare costs, enrollment, and demographics were used for this study; they were derived from the 2012 Centers for Medicare & Medicaid Services (CMS) beneficiary files and were forecast to 2014 based on CMS and US Census Bureau projections. Standard life and health actuarial techniques were used to calculate the cost and cost-effectiveness of lung cancer screening. The cost, incidence rates, mortality rates, and other parameters chosen by the authors were taken from actual Medicare data, and the modeled screenings are consistent with Medicare processes and procedures. Approximately 4.9 million high-risk Medicare beneficiaries would meet criteria for lung cancer screening in 2014. Without screening, Medicare patients newly diagnosed with lung cancer have an average life expectancy of approximately 3 years. Based on our analysis, the average annual cost of LDCT lung cancer screening in Medicare is estimated to be $241 per person screened. LDCT screening for lung cancer in Medicare beneficiaries aged 55 to 80 years with a history of ≥30 pack-years of smoking and who had smoked within 15 years is low cost, at approximately $1 per member per month. This assumes that 50% of these patients were screened. Such screening is also highly cost-effective, at <$19,000 per life-year saved. If all eligible Medicare beneficiaries had been screened and treated consistently from age 55 years, approximately 358,134 additional individuals with current or past lung cancer would be alive in 2014. LDCT screening is a low-cost and cost-effective strategy that fits well within the standard Medicare benefit, including its claims payment and quality monitoring.
Pyenson, Bruce S.; Henschke, Claudia I.; Yankelevitz, David F.; Yip, Rowena; Dec, Ellynne
2014-01-01
Background By a wide margin, lung cancer is the most significant cause of cancer death in the United States and worldwide. The incidence of lung cancer increases with age, and Medicare beneficiaries are often at increased risk. Because of its demonstrated effectiveness in reducing mortality, lung cancer screening with low-dose computed tomography (LDCT) imaging will be covered without cost-sharing starting January 1, 2015, by nongrandfathered commercial plans. Medicare is considering coverage for lung cancer screening. Objective To estimate the cost and cost-effectiveness (ie, cost per life-year saved) of LDCT lung cancer screening of the Medicare population at high risk for lung cancer. Methods Medicare costs, enrollment, and demographics were used for this study; they were derived from the 2012 Centers for Medicare & Medicaid Services (CMS) beneficiary files and were forecast to 2014 based on CMS and US Census Bureau projections. Standard life and health actuarial techniques were used to calculate the cost and cost-effectiveness of lung cancer screening. The cost, incidence rates, mortality rates, and other parameters chosen by the authors were taken from actual Medicare data, and the modeled screenings are consistent with Medicare processes and procedures. Results Approximately 4.9 million high-risk Medicare beneficiaries would meet criteria for lung cancer screening in 2014. Without screening, Medicare patients newly diagnosed with lung cancer have an average life expectancy of approximately 3 years. Based on our analysis, the average annual cost of LDCT lung cancer screening in Medicare is estimated to be $241 per person screened. LDCT screening for lung cancer in Medicare beneficiaries aged 55 to 80 years with a history of ≥30 pack-years of smoking and who had smoked within 15 years is low cost, at approximately $1 per member per month. This assumes that 50% of these patients were screened. Such screening is also highly cost-effective, at <$19,000 per life-year saved. Conclusion If all eligible Medicare beneficiaries had been screened and treated consistently from age 55 years, approximately 358,134 additional individuals with current or past lung cancer would be alive in 2014. LDCT screening is a low-cost and cost-effective strategy that fits well within the standard Medicare benefit, including its claims payment and quality monitoring. PMID:25237423
Quantitative verification of ab initio self-consistent laser theory.
Ge, Li; Tandy, Robert J; Stone, A D; Türeci, Hakan E
2008-10-13
We generalize and test the recent "ab initio" self-consistent (AISC) time-independent semiclassical laser theory. This self-consistent formalism generates all the stationary lasing properties in the multimode regime (frequencies, thresholds, internal and external fields, output power and emission pattern) from simple inputs: the dielectric function of the passive cavity, the atomic transition frequency, and the transverse relaxation time of the lasing transition.We find that the theory gives excellent quantitative agreement with full time-dependent simulations of the Maxwell-Bloch equations after it has been generalized to drop the slowly-varying envelope approximation. The theory is infinite order in the non-linear hole-burning interaction; the widely used third order approximation is shown to fail badly.
Mental health screening in immigration detention: A fresh look at Australian government data.
Young, Peter; Gordon, Michael S
2016-02-01
The poor mental health of asylum seekers and refugees in immigration detention has consistently been reported in peer-reviewed literature internationally; however, data on the mental health of asylum seekers and refugees detained in Australian immigration has been very limited. We re-analysed mental health screening data obtained by the Human Rights Commission. Longer time in detention was associated with higher self-reported depression scores, with female individuals being more vulnerable to time in detention than those of male gender. Approximately one-half of the refugee group who agreed to complete the Harvard Trauma Questionnaire had post-traumatic stress disorder symptoms. On clinician-rated measures, one-third of the children, adolescents and adults suffered with clinical symptoms requiring tertiary outpatient assessment. This paper consolidates the findings of the 2014 Australian Human Rights Commission report and it provides an argument for public reporting of refugee data. © The Royal Australian and New Zealand College of Psychiatrists 2016.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Shao, MeiYue; Lin, Lin; Yang, Chao
The single particle energies obtained in a Kohn-Sham density functional theory (DFT) calculation are generally known to be poor approximations to electron excitation energies that are measured in tr ansport, tunneling and spectroscopic experiments such as photo-emission spectroscopy. The correction to these energies can be obtained from the poles of a single particle Green’s function derived from a many-body perturbation theory. From a computational perspective, the accuracy and efficiency of such an approach depends on how a self energy term that properly accounts for dynamic screening of electrons is approximated. The G 0W 0 approximation is a widely used techniquemore » in which the self energy is expressed as the convolution of a noninteracting Green’s function (G 0) and a screened Coulomb interaction (W 0) in the frequency domain. The computational cost associated with such a convolution is high due to the high complexity of evaluating W 0 at multiple frequencies. In this paper, we discuss how the cost of G 0W 0 calculation can be reduced by constructing a low rank approximation to the frequency dependent part of W 0 . In particular, we examine the effect of such a low rank approximation on the accuracy of the G 0W 0 approximation. We also discuss how the numerical convolution of G 0 and W 0 can be evaluated efficiently and accurately by using a contour deformation technique with an appropriate choice of the contour.« less
Self-consistent-field KKR-CPA calculations in the atomic-sphere approximations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Singh, P.P. Gonis, A.; de Fontaine, D.
1991-12-03
We present a formulation of the Korringa-Kohn-Rostoker coherent potential approximation (KKR-CPA) for the treatment of substitutionally disordered alloys within the KKR atomic-sphere approximations (ASA). This KKR-ASA-CPA represents the first step toward the implementation of a full cell potential CPA, and combines the accuracy of the KKR-CPA method with the flexibility of treating complex crystal structures. The accuracy of this approach has been tested by comparing the self-consistent-field (SCF) KKR-ASA-CPA calculations of Cu-Pd alloys with experimental results and previous SCF-KKR-CPA calculations.
ERIC Educational Resources Information Center
Taylor, Purcell; El-Sabawi, Taleed; Cangin, Causenge
2016-01-01
Objective: To improve the CAGE (Cut down, Annoyed, Guilty, Eye opener) questionnaire's predictive accuracy in screening college students. Participants: The sample consisted of 219 midwestern university students who self-administered a confidential survey. Methods: Exploratory factor analysis, confirmatory factor analysis, receiver operating…
Electrostatic contribution to twist rigidity of DNA.
Mohammad-Rafiee, Farshid; Golestanian, Ramin
2004-06-01
The electrostatic contribution to the twist rigidity of DNA is studied, and it is shown that the Coulomb self-energy of the double-helical sugar-phosphate backbone makes a considerable contribution-the electrostatic twist rigidity of DNA is found to be C(elec) approximately 5 nm, which makes up about 7% of its total twist rigidity ( C(DNA) approximately 75 nm). The electrostatic twist rigidity is found, however, to depend only weakly on the salt concentration, because of a competition between two different screening mechanisms: (1) Debye screening by the salt ions in the bulk, and (2) structural screening by the periodic charge distribution along the backbone of the helical polyelectrolyte. It is found that, depending on the parameters, the electrostatic contribution to the twist rigidity could stabilize or destabilize the structure of a helical polyelectrolyte.
Low rank approximation in G 0W 0 calculations
Shao, MeiYue; Lin, Lin; Yang, Chao; ...
2016-06-04
The single particle energies obtained in a Kohn-Sham density functional theory (DFT) calculation are generally known to be poor approximations to electron excitation energies that are measured in tr ansport, tunneling and spectroscopic experiments such as photo-emission spectroscopy. The correction to these energies can be obtained from the poles of a single particle Green’s function derived from a many-body perturbation theory. From a computational perspective, the accuracy and efficiency of such an approach depends on how a self energy term that properly accounts for dynamic screening of electrons is approximated. The G 0W 0 approximation is a widely used techniquemore » in which the self energy is expressed as the convolution of a noninteracting Green’s function (G 0) and a screened Coulomb interaction (W 0) in the frequency domain. The computational cost associated with such a convolution is high due to the high complexity of evaluating W 0 at multiple frequencies. In this paper, we discuss how the cost of G 0W 0 calculation can be reduced by constructing a low rank approximation to the frequency dependent part of W 0 . In particular, we examine the effect of such a low rank approximation on the accuracy of the G 0W 0 approximation. We also discuss how the numerical convolution of G 0 and W 0 can be evaluated efficiently and accurately by using a contour deformation technique with an appropriate choice of the contour.« less
Primary prevention of HTLV-I in Japan.
Hino, S; Katamine, S; Miyata, H; Tsuji, Y; Yamabe, T; Miyamoto, T
1996-01-01
The ATL prevention program (AAP) in the Nagasaki Prefecture since 1987 consists of screening of pregnant women and asking the seropositives to refrain from breast-feeding. We screened approximately 90% of gravidas in the Prefecture and > 90% of the seropositive women agreed not to breast-feed. The maternal transmission rate dropped from approximately 20% to approximately 3%. PCR of cord bloods showed that 2.5% were PCR-positive. However, among formula-fed children, none of the cord-positives seroconverted, and none of the seropositives tested had been cord-positive. Breast-feeding for less than six months decreased the transmission rate significantly, but may have a higher transmission rate than the formula feeding.
Mathias, Patrick C; Turner, Emily H; Scroggins, Sheena M; Salipante, Stephen J; Hoffman, Noah G; Pritchard, Colin C; Shirts, Brian H
2016-03-01
To apply techniques for ancestry and sex computation from next-generation sequencing (NGS) data as an approach to confirm sample identity and detect sample processing errors. We combined a principal component analysis method with k-nearest neighbors classification to compute the ancestry of patients undergoing NGS testing. By combining this calculation with X chromosome copy number data, we determined the sex and ancestry of patients for comparison with self-report. We also modeled the sensitivity of this technique in detecting sample processing errors. We applied this technique to 859 patient samples with reliable self-report data. Our k-nearest neighbors ancestry screen had an accuracy of 98.7% for patients reporting a single ancestry. Visual inspection of principal component plots was consistent with self-report in 99.6% of single-ancestry and mixed-ancestry patients. Our model demonstrates that approximately two-thirds of potential sample swaps could be detected in our patient population using this technique. Patient ancestry can be estimated from NGS data incidentally sequenced in targeted panels, enabling an inexpensive quality control method when coupled with patient self-report. © American Society for Clinical Pathology, 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Samah, Asnarulkhadi Abu; Ahmadian, Maryam
2014-01-01
This study aimed to examine the relationship between body image satisfaction and breast self-screening behavior and intentions. The sample for this cross-sectional study consisted of 842 female university students who were recruited from a number of public and private universities. Data were obtained between the months of November and December, 2013, using multistage random cluster sampling. Main research variables were breast cancer screening behavior and intentions, demographic factors, and the total scores on each of the Multidimensional Body-Self Relations Questionnaire (MBSRQ-Appearance Scales) subscales. Results of multivariate analysis showed that having higher satisfaction and more positive evaluation of appearance were related to having performed breast self-examination more frequently in the last year and intending to perform breast self-examination more frequently in the next year. Longitudinal research can potentially provide detailed information about overall body image satisfaction and breast cancer screening behavior among various communities.
Self-consistency tests of large-scale dynamics parameterizations for single-column modeling
Edman, Jacob P.; Romps, David M.
2015-03-18
Large-scale dynamics parameterizations are tested numerically in cloud-resolving simulations, including a new version of the weak-pressure-gradient approximation (WPG) introduced by Edman and Romps (2014), the weak-temperature-gradient approximation (WTG), and a prior implementation of WPG. We perform a series of self-consistency tests with each large-scale dynamics parameterization, in which we compare the result of a cloud-resolving simulation coupled to WTG or WPG with an otherwise identical simulation with prescribed large-scale convergence. In self-consistency tests based on radiative-convective equilibrium (RCE; i.e., no large-scale convergence), we find that simulations either weakly coupled or strongly coupled to either WPG or WTG are self-consistent, butmore » WPG-coupled simulations exhibit a nonmonotonic behavior as the strength of the coupling to WPG is varied. We also perform self-consistency tests based on observed forcings from two observational campaigns: the Tropical Warm Pool International Cloud Experiment (TWP-ICE) and the ARM Southern Great Plains (SGP) Summer 1995 IOP. In these tests, we show that the new version of WPG improves upon prior versions of WPG by eliminating a potentially troublesome gravity-wave resonance.« less
Lipkus, Isaac M; Samsa, Gregory P; Dement, John; Skinner, Celette Sugg; Green, La Sonya G; Pompeii, Lisa; Ransohoff, David F
2003-11-01
Inaccuracy in self-reports of colorectal cancer (CRC) screening procedures (e.g., over- or underreporting) may interfere with individuals adhering to appropriate screening intervals, and can blur the true effects of physician recommendations to screen and the effects of interventions designed to promote screening. We assessed accuracy of self-report of having a fecal occult blood test (FOBT) within a 1-year window based on receipt of FOBT kits among individuals aged 50 and older in the carpentry trade (N = 658) who were off-schedule for having had a FOBT. Indices of evaluating accuracy of self-reports (concordance, specificity, false-positive and false-negative rates) were calculated relative to receipt of a mailed FOBT. Among those who mailed a completed FOBT, we assessed accuracy of reporting the test result. Participants underestimated having performed a FOBT (false-negative rate of 44%). Accuracy was unrelated to perceptions of getting or worrying about CRC or family history. Self-reports of having a negative FOBT result more consistently matched the laboratory result (specificity 98%) than having a positive test result (sensitivity 63%). Contrary to other findings, participants under- rather than over reported FOBT screening. Results suggest greater efforts are needed to enhance accurate recall of FOBT screening.
The self-referred mammography patient: a new responsibility for radiologists.
Monsees, B; Destouet, J M; Evens, R G
1988-01-01
A mammography screening program was initiated in which self-referred women were accepted for examination. Two views of each breast were obtained, and no physical examination was performed. Reports were sent to each patient and to the patient's primary care physician, if she had one. The program was successful in that the number of examinations performed per day increased from 36 to 80 within 6 months. Approximately 50% of the women who came for screening did so at their own request. Self-referred women with abnormal findings on mammograms who did not have a primary care physician were contacted by phone and told of the results. Advice was given for further evaluation, and the patient was referred to a local physician if she still did not know of one. Further workup in patients with abnormal findings was verified with the use of computer tracking and follow-up phone calls. Self-referral is an important component of screening mammography, but it places added responsibility on the radiologist in cases in which there is no referring physician.
Brown, Aidan T; Poon, Wilson C K; Holm, Christian; de Graaf, Joost
2017-02-08
Polar solvents like water support the bulk dissociation of themselves and their solutes into ions, and the re-association of these ions into neutral molecules in a dynamic equilibrium, e.g., H 2 O 2 ⇌ H + + HO 2 - . Using continuum theory, we study the influence of these association-dissociation reactions on the self-propulsion of colloids driven by surface chemical reactions (chemical swimmers). We find that association-dissociation reactions should have a strong influence on swimmers' behaviour, and therefore should be included in future modelling. In particular, such bulk reactions should permit charged swimmers to propel electrophoretically even if all species involved in the surface reactions are neutral. The bulk reactions also significantly modify the predicted speed of chemical swimmers propelled by ionic currents, by up to an order of magnitude. For swimmers whose surface reactions produce both anions and cations (ionic self-diffusiophoresis), the bulk reactions produce an additional reactive screening length, analogous to the Debye length in electrostatics. This in turn leads to an inverse relationship between swimmer radius and swimming speed, which could provide an alternative explanation for recent experimental observations on Pt-polystyrene Janus swimmers [S. Ebbens et al., Phys. Rev. E: Stat., Nonlinear, Soft Matter Phys., 2012, 85, 020401]. We also use our continuum theory to investigate the effect of the Debye screening length itself, going beyond the infinitely-thin-screening-length approximation used by previous analytical theories. We identify significant departures from this limiting behaviour for micron-sized swimmers under typical experimental conditions and find that the approximation fails entirely for nanoscale swimmers.
NASA Astrophysics Data System (ADS)
Li, L. L.; Partoens, B.; Peeters, F. M.
2018-04-01
By taking account of the electric-field-induced charge screening, a self-consistent calculation within the framework of the tight-binding approach is employed to obtain the electronic band structure of gated multilayer phosphorene and the charge densities on the different phosphorene layers. We find charge density and screening anomalies in single-gated multilayer phosphorene and electron-hole bilayers in dual-gated multilayer phosphorene. Due to the unique puckered lattice structure, both intralayer and interlayer charge screenings are important in gated multilayer phosphorene. We find that the electric-field tuning of the band structure of multilayer phosphorene is distinctively different in the presence and absence of charge screening. For instance, it is shown that the unscreened band gap of multilayer phosphorene decreases dramatically with increasing electric-field strength. However, in the presence of charge screening, the magnitude of this band-gap decrease is significantly reduced and the reduction depends strongly on the number of phosphorene layers. Our theoretical results of the band-gap tuning are compared with recent experiments and good agreement is found.
Davis, Karen K; Himmelfarb, Cheryl R Dennison; Szanton, Sarah L; Hayat, Matthew J; Allen, Jerilyn K
2015-01-01
Heart failure (HF) is associated with cognitive impairment, which could negatively affect a patient's abilities to carry out self-care, potentially resulting in higher hospital readmission rates. Factors associated with self-care in patients experiencing mild cognitive impairment (MCI) are not known. This descriptive correlation study aimed to assess levels of HF self-care and knowledge and to determine the predictors of self-care in HF patients who screen positive for MCI. The Montreal Cognitive Assessment was used to screen for MCI. In 125 patients with MCI hospitalized with HF, self-care (Self-care of Heart Failure Index) and HF knowledge (Dutch Heart Failure Knowledge Scale) were assessed. We used multiple regression analysis to test a model of variables hypothesized to predict self-care maintenance, management, and confidence. Mean (SD) HF knowledge scores (11.24 [1.84]) were above the level considered to be adequate (defined as >10). Mean (SD) scores for self-care maintenance (63.57 [19.12]), management (68.35 [20.24]), and confidence (64.99 [16.06]) were consistent with inadequate self-care (defined as scores <70). In multivariate analysis, HF knowledge, race, greater disease severity, and social support explained 22% of the variance in self-care maintenance (P < .001); age, education level, and greater disease severity explained 19% of the variance in self-care management (P < .001); and younger age and higher social support explained 20% of the variance in self-care confidence scores (P < .001). Blacks, on average, scored significantly lower in self-care maintenance (P = .03). In this sample, patients who screened positive for MCI, on average, had adequate HF knowledge yet inadequate self-care scores. These models show the influence of modifiable and nonmodifiable predictors for patients who screened positive for MCI across the domains of self-care. Health professionals should consider screening for MCI and identifying interventions that address HF knowledge and social support. Further research is needed to explain the racial differences in self-care.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Säkkinen, Niko; Peng, Yang; Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin-Dahlem
2015-12-21
We present a Kadanoff-Baym formalism to study time-dependent phenomena for systems of interacting electrons and phonons in the framework of many-body perturbation theory. The formalism takes correctly into account effects of the initial preparation of an equilibrium state and allows for an explicit time-dependence of both the electronic and phononic degrees of freedom. The method is applied to investigate the charge neutral and non-neutral excitation spectra of a homogeneous, two-site, two-electron Holstein model. This is an extension of a previous study of the ground state properties in the Hartree (H), partially self-consistent Born (Gd) and fully self-consistent Born (GD) approximationsmore » published in Säkkinen et al. [J. Chem. Phys. 143, 234101 (2015)]. Here, the homogeneous ground state solution is shown to become unstable for a sufficiently strong interaction while a symmetry-broken ground state solution is shown to be stable in the Hartree approximation. Signatures of this instability are observed for the partially self-consistent Born approximation but are not found for the fully self-consistent Born approximation. By understanding the stability properties, we are able to study the linear response regime by calculating the density-density response function by time-propagation. This amounts to a solution of the Bethe-Salpeter equation with a sophisticated kernel. The results indicate that none of the approximations is able to describe the response function during or beyond the bipolaronic crossover for the parameters investigated. Overall, we provide an extensive discussion on when the approximations are valid and how they fail to describe the studied exact properties of the chosen model system.« less
Lofters, Aisha; Vahabi, Mandana; Glazier, Richard H
2015-01-29
Self-report may not be an accurate method of determining cervical, breast and colorectal cancer screening rates due to recall, acquiescence and social desirability biases, particularly for certain sociodemographic groups. Therefore, the aims of this study were to determine the validity of self-report of cancer screening in Ontario, Canada, both for people in the general population and for socially disadvantaged groups based on immigrant status, ethnicity, education, income, language ability, self-rated health, employment status, age category (for cervical cancer screening), and gender (for fecal occult blood testing). We linked multiple data sources for this study, including the Canadian Community Health Survey and provincial-level health databases. Using administrative data as our gold standard, we calculated validity measures for self-report (i.e. sensitivity, specificity, positive and negative likelihood ratios, positive and negative predictive values), calculated report-to-record ratios, and conducted a multivariable regression analysis to determine which characteristics were independently associated with over-reporting of screening. Specificity was less than 70% overall and for all subgroups for cervical and breast cancer screening, and sensitivity was lower than 80% overall and for all subgroups for fecal occult blood testing FOBT. Report-to-record ratios were persistently significantly greater than 1 across all cancer screening types, highest for the FOBT group: 1.246 [1.189-1.306]. Regression analyses showed no consistent patterns, but sociodemographic characteristics were associated with over-reporting for each screening type. We have found that in Ontario, as in other jurisdictions, there is a pervasive tendency for people to over-report their cancer screening histories. Sociodemographic status also appears to influence over-reporting. Public health practitioners and policymakers need to be aware of the limitations of self-report and adjust their methods and interpretations accordingly.
Self-consistency in the phonon space of the particle-phonon coupling model
NASA Astrophysics Data System (ADS)
Tselyaev, V.; Lyutorovich, N.; Speth, J.; Reinhard, P.-G.
2018-04-01
In the paper the nonlinear generalization of the time blocking approximation (TBA) is presented. The TBA is one of the versions of the extended random-phase approximation (RPA) developed within the Green-function method and the particle-phonon coupling model. In the generalized version of the TBA the self-consistency principle is extended onto the phonon space of the model. The numerical examples show that this nonlinear version of the TBA leads to the convergence of results with respect to enlarging the phonon space of the model.
Labouliere, Christa D; Kleinman, Marjorie; Gould, Madelyn S
2015-04-01
The majority of suicidal adolescents have no contact with mental health services, and reduced help-seeking in this population further lessens the likelihood of accessing treatment. A commonly-reported reason for not seeking help is youths' perception that they should solve problems on their own. In this study, we explore associations between extreme self-reliance behavior (i.e., solving problems on your own all of the time), help-seeking behavior, and mental health symptoms in a community sample of adolescents. Approximately 2150 adolescents, across six schools, participated in a school-based suicide prevention screening program, and a subset of at-risk youth completed a follow-up interview two years later. Extreme self-reliance was associated with reduced help-seeking, clinically-significant depressive symptoms, and serious suicidal ideation at the baseline screening. Furthermore, in a subset of youth identified as at-risk at the baseline screening, extreme self-reliance predicted level of suicidal ideation and depressive symptoms two years later even after controlling for baseline symptoms. Given these findings, attitudes that reinforce extreme self-reliance behavior may be an important target for youth suicide prevention programs. Reducing extreme self-reliance in youth with suicidality may increase their likelihood of appropriate help-seeking and concomitant reductions in symptoms.
Labouliere, Christa D.; Kleinman, Marjorie; Gould, Madelyn S.
2015-01-01
The majority of suicidal adolescents have no contact with mental health services, and reduced help-seeking in this population further lessens the likelihood of accessing treatment. A commonly-reported reason for not seeking help is youths’ perception that they should solve problems on their own. In this study, we explore associations between extreme self-reliance behavior (i.e., solving problems on your own all of the time), help-seeking behavior, and mental health symptoms in a community sample of adolescents. Approximately 2150 adolescents, across six schools, participated in a school-based suicide prevention screening program, and a subset of at-risk youth completed a follow-up interview two years later. Extreme self-reliance was associated with reduced help-seeking, clinically-significant depressive symptoms, and serious suicidal ideation at the baseline screening. Furthermore, in a subset of youth identified as at-risk at the baseline screening, extreme self-reliance predicted level of suicidal ideation and depressive symptoms two years later even after controlling for baseline symptoms. Given these findings, attitudes that reinforce extreme self-reliance behavior may be an important target for youth suicide prevention programs. Reducing extreme self-reliance in youth with suicidality may increase their likelihood of appropriate help-seeking and concomitant reductions in symptoms. PMID:25837350
NASA Technical Reports Server (NTRS)
Walker, Kevin P.; Freed, Alan D.; Jordan, Eric H.
1993-01-01
Local stress and strain fields in the unit cell of an infinite, two-dimensional, periodic fibrous lattice have been determined by an integral equation approach. The effect of the fibres is assimilated to an infinite two-dimensional array of fictitious body forces in the matrix constituent phase of the unit cell. By subtracting a volume averaged strain polarization term from the integral equation we effectively embed a finite number of unit cells in a homogenized medium in which the overall stress and strain correspond to the volume averaged stress and strain of the constrained unit cell. This paper demonstrates that the zeroth term in the governing integral equation expansion, which embeds one unit cell in the homogenized medium, corresponds to the generalized self-consistent approximation. By comparing the zeroth term approximation with higher order approximations to the integral equation summation, both the accuracy of the generalized self-consistent composite model and the rate of convergence of the integral summation can be assessed. Two example composites are studied. For a tungsten/copper elastic fibrous composite the generalized self-consistent model is shown to provide accurate, effective, elastic moduli and local field representations. The local elastic transverse stress field within the representative volume element of the generalized self-consistent method is shown to be in error by much larger amounts for a composite with periodically distributed voids, but homogenization leads to a cancelling of errors, and the effective transverse Young's modulus of the voided composite is shown to be in error by only 23% at a void volume fraction of 75%.
Moryś, Joanna M; Bellwon, Jerzy; Adamczyk, Katarzyna; Gruchała, Marcin
2016-01-01
The presence of depression symptomatology significantly deteriorates the prognosis for the patient. There are many instruments developed to measure depression and anxiety in clinical trials; however, the suitability of the specific scale for screening these disorders in cardiovascular patients is debatable. The aim of current study is to verify which of the major assessment instruments is the most relevant for the screening evaluation of depression and anxiety in patients with cardiovascular system diseases. The sample studied consisted of 120 patients with stable coronary artery disease (CAD). They did not display serious psychiatric or somatic disorders. To assess depressive and anxiety symptoms we used self-reporting measures (BDI-II, HADS, SSAI/STAI, and PHQ), the results of which were compared to results obtained on the basis of a clinician-rating instrument (HRSD). We found that depressive symptoms assessed on the basis of HRSD, BDI-II, and PHQ-9 were equivalent in results, while the results obtained in HADS-D were significantly lower. Anxiety symptoms were found at approximate levels in HADS, SSAI, and GAD-7. The assessment of somatic symptoms in patients with CAD indicates that 87.5% of the subjects reported somatic symptoms of various intensity. Screening assessment of depression in patients with CAD gives different results depending on the tool used. We found that HADS significantly underestimates the percentage of patients with symptoms of depression in patients with CAD. Assessing anxiety symptoms with the aid of HADS gave outcomes close to the results gained by use of other tools.
Sheeran, T; Zimmerman, M
2004-03-01
We examined the factor structure of the Psychiatric Diagnostic Screening Questionnaire (PDSQ), a 125-item self-report scale that screens for 15 of the most common Axis I psychiatric disorders for which patients seek treatment in outpatient settings. The sample consisted of 2440 psychiatric outpatients. Thirteen factors were extracted. Ten mapped directly onto the DSM-IV diagnosis for which they were designed and one represented suicidal ideation. The remaining two factors reflected closely related disorders: Panic Disorder/Agoraphobia, and Somatization/Hypochondriasis. A psychosis factor was not extracted. Overall, the factor structure of the PDSQ was consistent with the DSM-IV nosology upon which it was developed.
Strong and weak adsorptions of polyelectrolyte chains onto oppositely charged spheres
NASA Astrophysics Data System (ADS)
Cherstvy, A. G.; Winkler, R. G.
2006-08-01
We investigate the complexation of long thin polyelectrolyte (PE) chains with oppositely charged spheres. In the limit of strong adsorption, when strongly charged PE chains adapt a definite wrapped conformation on the sphere surface, we analytically solve the linear Poisson-Boltzmann equation and calculate the electrostatic potential and the energy of the complex. We discuss some biological applications of the obtained results. For weak adsorption, when a flexible weakly charged PE chain is localized next to the sphere in solution, we solve the Edwards equation for PE conformations in the Hulthén potential, which is used as an approximation for the screened Debye-Hückel potential of the sphere. We predict the critical conditions for PE adsorption. We find that the critical sphere charge density exhibits a distinctively different dependence on the Debye screening length than for PE adsorption onto a flat surface. We compare our findings with experimental measurements on complexation of various PEs with oppositely charged colloidal particles. We also present some numerical results of the coupled Poisson-Boltzmann and self-consistent field equation for PE adsorption in an assembly of oppositely charged spheres.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bleiziffer, Patrick, E-mail: patrick.bleiziffer@fau.de; Krug, Marcel; Görling, Andreas
A self-consistent Kohn-Sham method based on the adiabatic-connection fluctuation-dissipation (ACFD) theorem, employing the frequency-dependent exact exchange kernel f{sub x} is presented. The resulting SC-exact-exchange-only (EXX)-ACFD method leads to even more accurate correlation potentials than those obtained within the direct random phase approximation (dRPA). In contrast to dRPA methods, not only the Coulomb kernel but also the exact exchange kernel f{sub x} is taken into account in the EXX-ACFD correlation which results in a method that, unlike dRPA methods, is free of self-correlations, i.e., a method that treats exactly all one-electron systems, like, e.g., the hydrogen atom. The self-consistent evaluation ofmore » EXX-ACFD total energies improves the accuracy compared to EXX-ACFD total energies evaluated non-self-consistently with EXX or dRPA orbitals and eigenvalues. Reaction energies of a set of small molecules, for which highly accurate experimental reference data are available, are calculated and compared to quantum chemistry methods like Møller-Plesset perturbation theory of second order (MP2) or coupled cluster methods [CCSD, coupled cluster singles, doubles, and perturbative triples (CCSD(T))]. Moreover, we compare our methods to other ACFD variants like dRPA combined with perturbative corrections such as the second order screened exchange corrections or a renormalized singles correction. Similarly, the performance of our EXX-ACFD methods is investigated for the non-covalently bonded dimers of the S22 reference set and for potential energy curves of noble gas, water, and benzene dimers. The computational effort of the SC-EXX-ACFD method exhibits the same scaling of N{sup 5} with respect to the system size N as the non-self-consistent evaluation of only the EXX-ACFD correlation energy; however, the prefactor increases significantly. Reaction energies from the SC-EXX-ACFD method deviate quite little from EXX-ACFD energies obtained non-self-consistently with dRPA orbitals and eigenvalues, and the deviation reduces even further if the Coulomb kernel is scaled by a factor of 0.75 in the dRPA to reduce self-correlations in the dRPA correlation potential. For larger systems, such a non-self-consistent EXX-ACFD method is a competitive alternative to high-level wave-function-based methods, yielding higher accuracy than MP2 and CCSD methods while exhibiting a better scaling of the computational effort than CCSD or CCSD(T) methods. Moreover, EXX-ACFD methods were shown to be applicable in situation characterized by static correlation.« less
Relativistic equation of state at subnuclear densities in the Thomas-Fermi approximation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Z. W.; Shen, H., E-mail: shennankai@gmail.com
We study the non-uniform nuclear matter using the self-consistent Thomas-Fermi approximation with a relativistic mean-field model. The non-uniform matter is assumed to be composed of a lattice of heavy nuclei surrounded by dripped nucleons. At each temperature T, proton fraction Y{sub p} , and baryon mass density ρ {sub B}, we determine the thermodynamically favored state by minimizing the free energy with respect to the radius of the Wigner-Seitz cell, while the nucleon distribution in the cell can be determined self-consistently in the Thomas-Fermi approximation. A detailed comparison is made between the present results and previous calculations in the Thomas-Fermimore » approximation with a parameterized nucleon distribution that has been adopted in the widely used Shen equation of state.« less
A Hydrodynamic Theory for Spatially Inhomogeneous Semiconductor Lasers: Microscopic Approach
NASA Technical Reports Server (NTRS)
Li, Jianzhong; Ning, C. Z.; Biegel, Bryan A. (Technical Monitor)
2001-01-01
Starting from the microscopic semiconductor Bloch equations (SBEs) including the Boltzmann transport terms in the distribution function equations for electrons and holes, we derived a closed set of diffusion equations for carrier densities and temperatures with self-consistent coupling to Maxwell's equation and to an effective optical polarization equation. The coherent many-body effects are included within the screened Hartree-Fock approximation, while scatterings are treated within the second Born approximation including both the in- and out-scatterings. Microscopic expressions for electron-hole (e-h) and carrier-LO (c-LO) phonon scatterings are directly used to derive the momentum and energy relaxation rates. These rates expressed as functions of temperatures and densities lead to microscopic expressions for self- and mutual-diffusion coefficients in the coupled density-temperature diffusion equations. Approximations for reducing the general two-component description of the electron-hole plasma (EHP) to a single-component one are discussed. In particular, we show that a special single-component reduction is possible when e-h scattering dominates over c-LO phonon scattering. The ambipolar diffusion approximation is also discussed and we show that the ambipolar diffusion coefficients are independent of e-h scattering, even though the diffusion coefficients of individual components depend sensitively on the e-h scattering rates. Our discussions lead to new perspectives into the roles played in the single-component reduction by the electron-hole correlation in momentum space induced by scatterings and the electron-hole correlation in real space via internal static electrical field. Finally, the theory is completed by coupling the diffusion equations to the lattice temperature equation and to the effective optical polarization which in turn couples to the laser field.
NASA Astrophysics Data System (ADS)
Hinuma, Yoyo; Kumagai, Yu; Tanaka, Isao; Oba, Fumiyasu
2017-02-01
The band alignment of prototypical semiconductors and insulators is investigated using first-principles calculations. A dielectric-dependent hybrid functional, where the nonlocal Fock exchange mixing is set at the reciprocal of the static electronic dielectric constant and the exchange correlation is otherwise treated as in the Perdew-Burke-Ernzerhof (PBE0) hybrid functional, is used as well as the Heyd-Scuseria-Ernzerhof (HSE06) hybrid and PBE semilocal functionals. In addition, these hybrid functionals are applied non-self-consistently to accelerate calculations. The systems considered include C and Si in the diamond structure, BN, AlP, AlAs, AlSb, GaP, GaAs, InP, ZnS, ZnSe, ZnTe, CdS, CdSe, and CdTe in the zinc-blende structure, MgO in the rocksalt structure, and GaN and ZnO in the wurtzite structure. Surface band positions with respect to the vacuum level, i.e., ionization potentials and electron affinities, and band offsets at selected zinc-blende heterointerfaces are evaluated as well as band gaps. The non-self-consistent approach speeds up hybrid functional calculations by an order of magnitude, while it is shown using HSE06 that the resultant band gaps and surface band positions are similar to the self-consistent results. The dielectric-dependent hybrid functional improves the band gaps and surface band positions of wide-gap systems over HSE06. The interfacial band offsets are predicted with a similar degree of precision. Overall, the performance of the dielectric-dependent hybrid functional is comparable to the G W0 approximation based on many-body perturbation theory in the prediction of band gaps and alignments for most systems. The present results demonstrate that the dielectric-dependent hybrid functional, particularly when applied non-self-consistently, is promising for applications to systematic calculations or high-throughput screening that demand both computational efficiency and sufficient accuracy.
NASA Astrophysics Data System (ADS)
Franchini, C.; Sanna, A.; Marsman, M.; Kresse, G.
2010-02-01
BaBiO3 is characterized by a charge disproportionation with half of the Bi atoms possessing a valence 3+ and half a valence 5+ . Because of self-interaction errors, local- and semilocal-density functionals fail to describe the charge disproportionation quantitatively, yielding a too small structural distortion and no band gap. Using hybrid functionals, we obtain a satisfactory description of the structural, electronic, optical, and vibrational properties of BaBiO3 . The results obtained using GW (Green’s function G and screened Coulomb potential W) based schemes on top of hybrid functionals, including fully self-consistent GW calculations with vertex corrections in the dielectric screening, qualitatively confirm the Heyd-Scuseria-Ernzerhof picture but a systematic overestimation of the band gap by about 0.4 eV is observed.
[Psychopathology screening in medical school students].
Galván-Molina, Jesús Francisco; Jiménez-Capdeville, María E; Hernández-Mata, José María; Arellano-Cano, José Ramón
2017-01-01
Screening of psychopathology and associated factors in medical students employing an electronic self-report survey. A transversal, observational, and comparative study that consisted of the following instruments: Sociodemographic survey; 2. Adult Self-Report Scale-V1 (ASRS); State-Trait Anxiety Inventory (STAI); Zung and Conde Self-Rating Depression Scale, Almonte-Herskovic Sexual Orientation Self-Report; Plutchik Suicide Risk Scale; Alcohol Use Disorders Identification Test Identification (AUDIT); Fagerström Test for Nicotine Dependence; 9. Maslach Burnout Inventory (MBI); Eating Disorder Inventory 2 (EDI). We gathered 323 student surveys from medical students of the first, third and sixth grades. The three more prevalent disorders were depression (24%), attention deficit disorders with hyperactivity (28%) and anxiety (13%); the prevalence of high-level burnout syndrome was 13%. Also, the fifth part of the students had detrimental use of tobacco and alcohol. Sixty percent of medical students had either one or more probable disorder or burnout. An adequate screening and treatment of this population could prevent severe mental disorders and the associated factors could help us to create a risk profile. This model is an efficient research tool for screening and secondary prevention.
Influence of defects on the absorption edge of InN thin films: The band gap value
NASA Astrophysics Data System (ADS)
Thakur, J. S.; Danylyuk, Y. V.; Haddad, D.; Naik, V. M.; Naik, R.; Auner, G. W.
2007-07-01
We investigate the optical-absorption spectra of InN thin films whose electron density varies from ˜1017tõ1021cm-3 . The low-density films are grown by molecular-beam-epitaxy deposition while highly degenerate films are grown by plasma-source molecular-beam epitaxy. The optical-absorption edge is found to increase from 0.61to1.90eV as the carrier density of the films is increased from low to high density. Since films are polycrystalline and contain various types of defects, we discuss the band gap values by studying the influence of electron degeneracy, electron-electron, electron-ionized impurities, and electron-LO-phonon interaction self-energies on the spectral absorption coefficients of these films. The quasiparticle self-energies of the valence and conduction bands are calculated using dielectric screening within the random-phase approximation. Using one-particle Green’s function analysis, we self-consistently determine the chemical potential for films by coupling equations for the chemical potential and the single-particle scattering rate calculated within the effective-mass approximation for the electron scatterings from ionized impurities and LO phonons. By subtracting the influence of self-energies and chemical potential from the optical-absorption edge energy, we estimate the intrinsic band gap values for the films. We also determine the variations in the calculated band gap values due to the variations in the electron effective mass and static dielectric constant. For the lowest-density film, the estimated band gap energy is ˜0.59eV , while for the highest-density film, it varies from ˜0.60tõ0.68eV depending on the values of electron effective mass and dielectric constant.
Positive attitudes and self-harming behavior of adolescents in a juvenile detention house in Taiwan.
Tsai, Mei-Hua; Fang, Kai-Chi; Lu, Chia-Hui; Chen, Chih-Dao; Hsieh, Chi-Pan; Chen, Tsung-Tai
2011-08-01
This study aimed to evaluate the less stigmatizing positivity construct screening measurement and its association with recent self-harming behaviors among adolescents. Participants were 193 detained Taiwanese adolescents. Questionnaires consisted of a deliberate self-harm inventory, a positivity construct measurement, a depression scale, data concerning risky health behaviors and demographics. The prevalence rate of recent self-harming behavior among adolescents in the detention house was 43.5%. The logistic model showed that age, gender and level of positivity demonstrated significant odds ratios for self-harm behavior. Results showed that younger age and female gender increased self-harming behavior. In addition, low score on positivity construct screening measurement increased the probability of self-harming behavior. Furthermore, these adolescents also engaged in risky health behaviors and were more depressed. Parental and school awareness for these risky behaviors should be enhanced and appropriate early interventions implemented to prevent negative health outcomes.
Donnellan, M Brent; Kenny, David A; Trzesniewski, Kali H; Lucas, Richard E; Conger, Rand D
2012-12-01
The present research used a latent variable trait-state model to evaluate the longitudinal consistency of self-esteem during the transition from adolescence to adulthood. Analyses were based on ten administrations of the Rosenberg Self-Esteem scale (Rosenberg, 1965) spanning the ages of approximately 13 to 32 for a sample of 451 participants. Results indicated that a completely stable trait factor and an autoregressive trait factor accounted for the majority of the variance in latent self-esteem assessments, whereas state factors accounted for about 16% of the variance in repeated assessments of latent self-esteem. The stability of individual differences in self-esteem increased with age consistent with the cumulative continuity principle of personality development.
Donnellan, M. Brent; Kenny, David A.; Trzesniewski, Kali H.; Lucas, Richard E.; Conger, Rand D.
2012-01-01
The present research used a latent variable trait-state model to evaluate the longitudinal consistency of self-esteem during the transition from adolescence to adulthood. Analyses were based on ten administrations of the Rosenberg Self-Esteem scale (Rosenberg, 1965) spanning the ages of approximately 13 to 32 for a sample of 451 participants. Results indicated that a completely stable trait factor and an autoregressive trait factor accounted for the majority of the variance in latent self-esteem assessments, whereas state factors accounted for about 16% of the variance in repeated assessments of latent self-esteem. The stability of individual differences in self-esteem increased with age consistent with the cumulative continuity principle of personality development. PMID:23180899
NASA Astrophysics Data System (ADS)
Cunningham, Brian; Grüning, Myrta; Azarhoosh, Pooya; Pashov, Dimitar; van Schilfgaarde, Mark
2018-03-01
We present an approach to calculate the optical absorption spectra that combines the quasiparticle self-consistent GW method [Phys. Rev. B 76, 165106 (2007), 10.1103/PhysRevB.76.165106] for the electronic structure with the solution of the ladder approximation to the Bethe-Salpeter equation for the macroscopic dielectric function. The solution of the Bethe-Salpeter equation has been implemented within an all-electron framework, using a linear muffin-tin orbital basis set, with the contribution from the nonlocal self-energy to the transition dipole moments (in the optical limit) evaluated explicitly. This approach addresses those systems whose electronic structure is poorly described within the standard perturbative GW approaches with density-functional theory calculations as a starting point. The merits of this approach have been exemplified by calculating optical absorption spectra of a strongly correlated transition metal oxide, NiO, and a narrow gap semiconductor, Ge. In both cases, the calculated spectrum is in good agreement with the experiment. It is also shown that for systems whose electronic structure is well-described within the standard perturbative GW , such as Si, LiF, and h -BN , the performance of the present approach is in general comparable to the standard GW plus Bethe-Salpeter equation. It is argued that both vertex corrections to the electronic screening and the electron-phonon interaction are responsible for the observed systematic overestimation of the fundamental band gap and spectrum onset.
Utilization of screening mammography in New Hampshire: a population-based assessment.
Carney, Patricia A; Goodrich, Martha E; Mackenzie, Todd; Weiss, Julia E; Poplack, Steven P; Wells, Wendy S; Titus-Ernstoff, Linda
2005-10-15
The objective of screening mammography is to identify breast carcinoma early, which requires routine screening. Although self-report data indicate that screening utilization is high, the results of this population-based assessment indicated that utilization is lower than reported previously. The authors compared New Hampshire population data from the 2000 Census with clinical encounter data for the corresponding time obtained from the New Hampshire Mammography Network, a mammography registry that captures approximately 90% of the mammograms performed in participating New Hampshire facilities. The results showed that approximately 36% of New Hampshire women either never had a mammogram or had not had a mammogram in > 27 months (irregular screenees), and older women (80 yrs and older) were less likely to be screened (79% unscreened/underscreened) compared with younger women (ages 40-69 yrs; 28-32% unscreened/underscreened). Of the screened women, 44% were adhering to an interval of 14 months, and 21% were adhering within 15 months and 26 months. The remaining 35% of the women had 1 or 2 mammograms and did not return within 27 months. Routine mammography screening may be occurring less often than believed when survey data alone are used. An important, compelling concern is the reason women had one or two mammograms only and then did not return for additional screening. This area deserves additional research. Copyright 2005 American Cancer Society
Analytic approximation for random muffin-tin alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mills, R.; Gray, L.J.; Kaplan, T.
1983-03-15
The methods introduced in a previous paper under the name of ''traveling-cluster approximation'' (TCA) are applied, in a multiple-scattering approach, to the case of a random muffin-tin substitutional alloy. This permits the iterative part of a self-consistent calculation to be carried out entirely in terms of on-the-energy-shell scattering amplitudes. Off-shell components of the mean resolvent, needed for the calculation of spectral functions, are obtained by standard methods involving single-site scattering wave functions. The single-site TCA is just the usual coherent-potential approximation, expressed in a form particularly suited for iteration. A fixed-point theorem is proved for the general t-matrix TCA, ensuringmore » convergence upon iteration to a unique self-consistent solution with the physically essential Herglotz properties.« less
Sachser, Cedric; Berliner, Lucy; Holt, Tonje; Jensen, Tine K; Jungbluth, Nathaniel; Risch, Elizabeth; Rosner, Rita; Goldbeck, Lutz
2017-03-01
Systematic screening is a powerful means by which children and adolescents with posttraumatic stress symptoms (PTSS) can be detected. Reliable and valid measures based on current diagnostic criteria are needed. To investigate the internal consistency and construct validity of the Child and Adolescent Trauma Screen (CATS) in three samples of trauma-exposed children in the US (self-reports: n=249; caregiver reports: n=267; pre-school n=190), in Germany (self-reports: n=117; caregiver reports: n=95) and in Norway (self-reports: n=109; caregiver reports: n=62). Internal consistency was calculated using Cronbach's α. Convergent-discriminant validity was investigated using bivariate correlation coefficients with measures of depression, anxiety and externalizing symptoms. CFA was used to investigate the DSM-5 factor structure. In all three language samples the 20 item symptom score of the self-report and the caregiver report proved good to excellent reliability with α ranging between .88 and .94. The convergent-discriminant validity pattern showed medium to strong correlations with measures of depression (r =.62-.82) and anxiety (r =.40-.77) and low to medium correlations with externalizing symptoms (r =-.15-.43) within informants in all language versions. Using CFA the underlying DSM-5 factor structure with four symptom clusters (re-experiencing, avoidance, negative alterations in mood and cognitions, hyperarousal) was supported (n =475 for self-report; n =424 for caregiver reports). The external validation of the CATS with a DSM-5 based semi-structured clinical interview and corresponding determination of cut-points is pending. The CATS has satisfactory psychometric properties. Clinicians may consider the CATS as a screening tool and for symptom monitoring. Copyright © 2016 Elsevier B.V. All rights reserved.
Daily self-sampling for high-risk human papillomavirus (HR-HPV) testing.
Sanner, Karin; Wikström, Ingrid; Gustavsson, Inger; Wilander, Erik; Lindberg, Julia Hedlund; Gyllensten, Ulf; Olovsson, Matts
2015-12-01
Self-sampling for HPV as part of primary screening is a well-tolerated method for women not attending organized Pap smear screening and could increase coverage of cervical cancer screening. To investigate if the prevalence of HR-HPV varies from day to day in infected women and if one single sample is reliable for detecting an ongoing infection. This is a prospective cohort study on 12 premenopausal and 13 postmenopausal women performing daily self-sampling for HR-HPV testing. They were all HR-HPV-positive 1-3 months ago. Postmenopausal women were sampled for 28 days and premenopausal women sampled during bleeding-free days in one menstrual cycle. A possible difference in viral load between the estrogen-dominated proliferative phase and the progesterone-dominated secretory phase was analyzed. Consistent results throughout the sampling period were observed for 19 women, with either a daily presence of HPV (14 women) or no HPV at all during the sampling period (5 women). Of 607 samples from 25 women, 596 were consistently positive or negative for HPV during the sampling period and 11 were inconsistent (2%). There was no difference in HPV copy number between the estrogen dominated proliferative or progesterone dominated secretory menstrual cycle phases. The major finding was a high degree of consistency concerning HR-HPV positivity and negativity of HR-HPV in vaginal fluid during a sustained period of daily self-sampling. It does not appear to matter whether the sample is collected in the proliferative or secretory phase. Copyright © 2015 Elsevier B.V. All rights reserved.
Hovens, J E; Bramsen, I; van der Ploeg, H M
2002-06-01
The Self-rating Inventory for Posttraumatic Stress Disorder of 22 items was developed for use with populations without identified traumatic experiences. The inventory has been used extensively in survey research in The Netherlands. This paper examines the psychometric properties. In four different groups (trauma and psychiatric patients, elderly Dutch subjects, former peacekeepers, and medical students) internal consistency, test-retest reliability, concurrent and discriminant validity, and sensitivity and specificity are analyzed. The inventory showed good internal consistency, test-retest reliability, concurrent and discriminant validity, and high sensitivity and specificity. It appears to be valuable for survey research on posttraumatic stress in nonselected populations. As a screening device, high sensitivity for PTSD symptoms is evident even when the traumatic event has not been defined.
ERIC Educational Resources Information Center
Smith, Gregory J
2007-01-01
Approximately three months before starting college, 203 high school seniors completed a questionnaire consisting of the General Self-Efficacy Scale, the Rosenberg Self-Esteem Scale, and the Parental Authority Questionnaire (PAQ) assessing their parents' parenting styles. The PAQ yielded scores on three parenting styles originally proposed by…
Lauw, Y; Leermakers, F A M; Stuart, M A Cohen
2007-07-19
The persistence length of a wormlike micelle composed of ionic surfactants C(n)E(m)X(k) in an aqueous solvent is predicted by means of the self-consistent-field theory where C(n)E(m) is the conventional nonionic surfactant and X(k) is an additional sequence of k weakly charged (pH-dependent) segments. By considering a toroidal micelle at infinitesimal curvature, we evaluate the bending modulus of the wormlike micelle that corresponds to the total persistence length, consisting of an elastic/intrinsic and an electrostatic contribution. The total persistence length increases with pH and decreases with increasing background salt concentration. We estimate that the electrostatic persistence length l(p,e)(0) scales with respect to the Debye length kappa(-1) as l(p,e)(0) approximately kappa(-p) where p approximately 1.98 for wormlike micelles consisting of C(20)E(10)X(1) surfactants and p approximately 1.54 for wormlike micelles consisting of C(20)E(10)X(2) surfactants. The total persistence length l(p,t)(0) is a weak function of the head group length m but scales with the tail length n as l(p,t)(0) approximately n(x) where x approximately 2-2.6, depending on the corresponding head group length. Interestingly, l(p,t)(0) varies nonmonotonically with the number of charged groups k due to the opposing trends in the electrostatic and elastic bending rigidities upon variation of k.
Zehbe, Ingeborg; Jackson, Robert; Wood, Brianne; Weaver, Bruce; Escott, Nicholas; Severini, Alberto; Krajden, Mel; Bishop, Lisa; Morrisseau, Kyla; Ogilvie, Gina; Burchell, Ann N; Little, Julian
2016-01-01
Objectives The incidence of cervical cancer is up to 20-fold higher among First Nations women in Canada than the general population, probably due to lower participation in screening. Offering human papillomavirus (HPV) self-sampling in place of Papanicolaou (Pap) testing may eventually increase screening participation and reduce cervical cancer rates in this population. Design A community-randomised controlled screening trial. Setting First Nations communities in Northwest Ontario, Canada. Participants Women aged between 25 and 69, living in Robinson Superior Treaty First Nations. The community was the unit of randomisation. Interventions Women were asked to complete a questionnaire and have screening by HPV self-sampling (arm A) or Pap testing (arm B). Primary outcome measures The number of women who participated in cervical screening. Randomisation Community clusters were randomised to include approximately equivalent numbers of women in each arm. Results 6 communities were randomised to arm A and 5 to arm B. One community withdrew, leaving 5 communities in each group (834 eligible women). Participation was <25%. Using clustered intention-to-treat (ITT) analysis, initial and cumulative averaged uptakes in arm A were 1.4-fold (20% vs 14.3%, p=0.628) and 1.3-fold (20.6% vs 16%, p=0.694) higher compared to arm B, respectively. Corresponding per protocol (PP) analysis indicates 2.2-fold (22.9% vs 10.6%, p=0.305) and 1.6-fold (22.9% vs 14.1%, p=0.448) higher uptakes in arm A compared to arm B. Screening uptake varied between communities (range 0–62.1%). Among women who completed a questionnaire (18.3% in arm A, 21.7% in arm B), the screening uptake was 1.8-fold (ITT; p=0.1132) or 3-fold (PP; p<0.01) higher in arm A versus arm B. Conclusions Pap and HPV self-sampling were compared in a marginalised, Canadian population. Results indicated a preference for self-sampling. More research on how to reach underscreened Indigenous women is necessary. Trial registration number ISRCTN84617261. PMID:27855089
Screening for learning disabilities in young adult career counseling.
Kasler, Jon; Fawcett, Angela
2009-01-01
The Strengths and Weaknesses Academic Profile (SWAP) was constructed in Israel in response to the local need of career counselors for a valid, reliable, comprehensive, parsimonious, and computerized screening device for identifying those likely to be at risk of learning disabilities (LD). The method chosen was self-report. A set of cognitive items was written and divided into seven scales: reading, writing, attention and memory, computation, English as a foreign language (EFL), study skills, and self-image. The screening tool was validated on a research sample in Sheffield, UK, based on comparison of the results obtained from the screening with the results of standardized diagnosis of learning disabilities administered to the respondents. The questionnaire was administered to 39 students, half of them diagnosed for dyslexia and half tested and found to be free of dyslexia. Results indicate that SWAP is a reliable and valid questionnaire, with a classification power of approximately 90%. The questionnaire is now widely used in Israel, where an Internet site has been constructed to administer the questionnaire and provide immediate and direct results.
Akhtar, Usman; Keller, Heather H; Tate, Robert B; Lengyel, Christina O
2015-12-01
Brief nutrition screening tools are desired for research and practice. Seniors in the Community: Risk Evaluation for Eating and Nutrition (SCREEN-II, 14 items) and the abbreviated version SCREEN-II-AB (8 items) are valid and reliable nutrition screening tools for older adults. This exploratory study used a retrospective cross-sectional design to determine the construct validity of a subset of 3 items (weight loss, appetite, and swallowing difficulty) currently on the SCREEN-II and SCREEN-II-AB tools. Secondary data on community-dwelling senior males (n = 522, mean ± SD age = 86.7 ± 3.0 years) in the Manitoba Follow-up Study (MFUS) study were available for analysis. Participants completed the mailed MFUS Nutrition Survey that included SCREEN-II items and questions pertaining to self-rated health, diet healthiness, and rating of the importance of nutrition towards successful aging as the constructs for comparison. Self-perceived health status (F = 14.7, P < 0.001), diet healthiness (ρ = 0.17, P = 0.002) and the rating of nutrition's importance to aging (ρ = 0.10, P = 0.03) were correlated with the 3-item score. Inferences were consistent with associations between these construct variables and the full SCREEN-II. Three items from SCREEN-II and SCREEN-II-AB demonstrate initial construct validity with self-perceived health status and diet healthiness ratings by older males; further exploration for criterion and predictive validity in more diverse samples is needed.
Willingness to Participate in Cancer Screenings: Blacks vs Whites vs Puerto Rican Hispanics
Katz, Ralph V.; Claudio, Cristina; Kressin, Nancy R.; Green, B. Lee; Wang, Min Qi; Russell, Stefanie Luise
2009-01-01
Background In the United States, blacks and Hispanics have lower cancer screening rates than whites have. Studies on the screening behaviors of minorities are increasing, but few focus on the factors that contribute to this discrepancy. This study presents the self-reported willingness by blacks, Puerto Rican Hispanics, and non-Hispanic whites to participate in cancer screenings in differing cancer screening situations. Methods The Cancer Screening Questionnaire (CSQ), a 60-item questionnaire, was administered via random-digit-dial telephone interviews to adults in three cities: Baltimore, Maryland; New York, New York; and, San Juan, Puerto Rico. Results The 1,148 participants in the CSQ study sample consisted of 355 blacks, 311 Puerto Rican Hispanics, and 482 non-Hispanic whites. Response rates ranged from 45% to 58% by city. Multivariable logistic regression analyses revealed that blacks and Puerto Ricans were often more likely (OR 2.0-3.0) and never less likely than whites to self-report willingness to participate in cancer screenings regardless of who conducted the cancer screening, what one was asked to do in the cancer screening, or what type of cancer was involved (with the exception of skin cancer where blacks, compared with whites, had an OR of 0.5). Conclusions The findings from this study provide evidence that blacks and Hispanics self-report that they are either as willing or more willing than whites to participate in cancer screening programs. PMID:18813201
2011-01-01
Background Approximately one third of New Zealand children and young people are overweight or obese. A similar proportion (33%) do not meet recommendations for physical activity, and 70% do not meet recommendations for screen time. Increased time being sedentary is positively associated with being overweight. There are few family-based interventions aimed at reducing sedentary behavior in children. The aim of this trial is to determine the effects of a 24 week home-based, family oriented intervention to reduce sedentary screen time on children's body composition, sedentary behavior, physical activity, and diet. Methods/Design The study design is a pragmatic two-arm parallel randomized controlled trial. Two hundred and seventy overweight children aged 9-12 years and primary caregivers are being recruited. Participants are randomized to intervention (family-based screen time intervention) or control (no change). At the end of the study, the control group is offered the intervention content. Data collection is undertaken at baseline and 24 weeks. The primary trial outcome is child body mass index (BMI) and standardized body mass index (zBMI). Secondary outcomes are change from baseline to 24 weeks in child percentage body fat; waist circumference; self-reported average daily time spent in physical and sedentary activities; dietary intake; and enjoyment of physical activity and sedentary behavior. Secondary outcomes for the primary caregiver include change in BMI and self-reported physical activity. Discussion This study provides an excellent example of a theory-based, pragmatic, community-based trial targeting sedentary behavior in overweight children. The study has been specifically designed to allow for estimation of the consistency of effects on body composition for Māori (indigenous), Pacific and non-Māori/non-Pacific ethnic groups. If effective, this intervention is imminently scalable and could be integrated within existing weight management programs. Trial Registration ACTRN12611000164998 PMID:21718543
Lenselink, Charlotte H.; de Bie, Roosmarie P.; van Hamont, Dennis; Bakkers, Judith M. J. E.; Quint, Wim G. V.; Massuger, Leon F. A. G.; Bekkers, Ruud L. M.; Melchers, Willem J. G.
2009-01-01
This study assesses human papillomavirus (HPV) detection and genotyping in self-sampled genital smears applied to an indicating FTA elute cartridge (FTA cartridge). The study group consisted of 96 women, divided into two sample sets. All samples were analyzed by the HPV SPF10-Line Blot 25. Set 1 consisted of 45 women attending the gynecologist; all obtained a self-sampled cervicovaginal smear, which was applied to an FTA cartridge. HPV results were compared to a cervical smear (liquid based) taken by a trained physician. Set 2 consisted of 51 women who obtained a self-sampled cervicovaginal smear at home, which was applied to an FTA cartridge and to a liquid-based medium. DNA was obtained from the FTA cartridges by simple elution as well as extraction. Of all self-obtained samples of set 1, 62.2% tested HPV positive. The overall agreement between self- and physician-obtained samples was 93.3%, in favor of the self-obtained samples. In sample set 2, 25.5% tested HPV positive. The overall agreement for high-risk HPV presence between the FTA cartridge and liquid-based medium and between DNA elution and extraction was 100%. This study shows that HPV detection and genotyping in self-obtained cervicovaginal samples applied to an FTA cartridge is highly reliable. It shows a high level of overall agreement with HPV detection and genotyping in physician-obtained cervical smears and liquid-based self-samples. DNA can be obtained by simple elution and is therefore easy, cheap, and fast. Furthermore, the FTA cartridge is a convenient medium for collection and safe transport at ambient temperatures. Therefore, this method may contribute to a new way of cervical cancer screening. PMID:19553570
Lenselink, Charlotte H; de Bie, Roosmarie P; van Hamont, Dennis; Bakkers, Judith M J E; Quint, Wim G V; Massuger, Leon F A G; Bekkers, Ruud L M; Melchers, Willem J G
2009-08-01
This study assesses human papillomavirus (HPV) detection and genotyping in self-sampled genital smears applied to an indicating FTA elute cartridge (FTA cartridge). The study group consisted of 96 women, divided into two sample sets. All samples were analyzed by the HPV SPF(10)-Line Blot 25. Set 1 consisted of 45 women attending the gynecologist; all obtained a self-sampled cervicovaginal smear, which was applied to an FTA cartridge. HPV results were compared to a cervical smear (liquid based) taken by a trained physician. Set 2 consisted of 51 women who obtained a self-sampled cervicovaginal smear at home, which was applied to an FTA cartridge and to a liquid-based medium. DNA was obtained from the FTA cartridges by simple elution as well as extraction. Of all self-obtained samples of set 1, 62.2% tested HPV positive. The overall agreement between self- and physician-obtained samples was 93.3%, in favor of the self-obtained samples. In sample set 2, 25.5% tested HPV positive. The overall agreement for high-risk HPV presence between the FTA cartridge and liquid-based medium and between DNA elution and extraction was 100%. This study shows that HPV detection and genotyping in self-obtained cervicovaginal samples applied to an FTA cartridge is highly reliable. It shows a high level of overall agreement with HPV detection and genotyping in physician-obtained cervical smears and liquid-based self-samples. DNA can be obtained by simple elution and is therefore easy, cheap, and fast. Furthermore, the FTA cartridge is a convenient medium for collection and safe transport at ambient temperatures. Therefore, this method may contribute to a new way of cervical cancer screening.
Isoscalar and isovector giant resonances in a self-consistent phonon coupling approach
NASA Astrophysics Data System (ADS)
Lyutorovich, N.; Tselyaev, V.; Speth, J.; Krewald, S.; Grümmer, F.; Reinhard, P.-G.
2015-10-01
We present fully self-consistent calculations of isoscalar giant monopole and quadrupole as well as isovector giant dipole resonances in heavy and light nuclei. The description is based on Skyrme energy-density functionals determining the static Hartree-Fock ground state and the excitation spectra within random-phase approximation (RPA) and RPA extended by including the quasiparticle-phonon coupling at the level of the time-blocking approximation (TBA). All matrix elements were derived consistently from the given energy-density functional and calculated without any approximation. As a new feature in these calculations, the single-particle continuum was included thus avoiding the artificial discretization usually implied in RPA and TBA. The step to include phonon coupling in TBA leads to small, but systematic, down shifts of the centroid energies of the giant resonances. These shifts are similar in size for all Skyrme parametrizations investigated here. After all, we demonstrate that one can find Skyrme parametrizations which deliver a good simultaneous reproduction of all three giant resonances within TBA.
Screening for frailty in older adults using a self-reported instrument.
Nunes, Daniella Pires; Duarte, Yeda Aparecida de Oliveira; Santos, Jair Lício Ferreira; Lebrão, Maria Lúcia
2015-01-01
OBJECTIVE To validate a screening instrument using self-reported assessment of frailty syndrome in older adults. METHODS This cross-sectional study used data from the Saúde, Bem-estar e Envelhecimento study conducted in Sao Paulo, SP, Southeastern Brazil. The sample consisted of 433 older adult individuals (≥ 75 years) assessed in 2009. The self-reported instrument can be applied to older adults or their proxy respondents and consists of dichotomous questions directly related to each component of the frailty phenotype, which is considered the gold standard model: unintentional weight loss, fatigue, low physical activity, decreased physical strength, and decreased walking speed. The same classification proposed in the phenotype was utilized: not frail (no component identified); pre-frail (presence of one or two components), and frail (presence of three or more components). Because this is a screening instrument, "process of frailty" was included as a category (pre-frail and frail). Cronbach's α was used in psychometric analysis to evaluate the reliability and validity of the criterion, the sensitivity, the specificity, as well as positive and negative predictive values. Factor analysis was used to assess the suitability of the proposed number of components. RESULTS Decreased walking speed and decreased physical strength showed good internal consistency (α = 0.77 and 0.72, respectively); however, low physical activity was less satisfactory (α = 0.63). The sensitivity and specificity for identifying pre-frail individuals were 89.7% and 24.3%, respectively, while those for identifying frail individuals were 63.2% and 71.6%, respectively. In addition, 89.7% of the individuals from both the evaluations were identified in the "process of frailty" category. CONCLUSIONS The self-reported assessment of frailty can identify the syndrome among older adults and can be used as a screening tool. Its advantages include simplicity, rapidity, low cost, and ability to be used by different professionals.
Screening for frailty in older adults using a self-reported instrument
Nunes, Daniella Pires; Duarte, Yeda Aparecida de Oliveira; Santos, Jair Lício Ferreira; Lebrão, Maria Lúcia
2015-01-01
OBJECTIVE To validate a screening instrument using self-reported assessment of frailty syndrome in older adults. METHODS This cross-sectional study used data from the Saúde, Bem-estar e Envelhecimento study conducted in Sao Paulo, SP, Southeastern Brazil. The sample consisted of 433 older adult individuals (≥ 75 years) assessed in 2009. The self-reported instrument can be applied to older adults or their proxy respondents and consists of dichotomous questions directly related to each component of the frailty phenotype, which is considered the gold standard model: unintentional weight loss, fatigue, low physical activity, decreased physical strength, and decreased walking speed. The same classification proposed in the phenotype was utilized: not frail (no component identified); pre-frail (presence of one or two components), and frail (presence of three or more components). Because this is a screening instrument, “process of frailty” was included as a category (pre-frail and frail). Cronbach’s α was used in psychometric analysis to evaluate the reliability and validity of the criterion, the sensitivity, the specificity, as well as positive and negative predictive values. Factor analysis was used to assess the suitability of the proposed number of components. RESULTS Decreased walking speed and decreased physical strength showed good internal consistency (α = 0.77 and 0.72, respectively); however, low physical activity was less satisfactory (α = 0.63). The sensitivity and specificity for identifying pre-frail individuals were 89.7% and 24.3%, respectively, while those for identifying frail individuals were 63.2% and 71.6%, respectively. In addition, 89.7% of the individuals from both the evaluations were identified in the “process of frailty” category. CONCLUSIONS The self-reported assessment of frailty can identify the syndrome among older adults and can be used as a screening tool. Its advantages include simplicity, rapidity, low cost, and ability to be used by different professionals. PMID:25741658
Martinez, Kathryn A; Pollack, Craig E; Phelan, Darcy F; Markakis, Diane; Bone, Lee; Shapiro, Gary; Wenzel, Jennifer; Howerton, Mollie; Johnson, Lawrence; Garza, Mary A; Ford, Jean G
2013-06-01
Previous research has shown colorectal cancer (CRC) screening disparities by gender. Little research has focused primarily on gender differences among older Black individuals, and reasons for existing gender differences remain poorly understood. We used baseline data from the Cancer Prevention and Treatment Demonstration Screening Trial. Participants were recruited from November 2006 to March 2010. In-person interviews were used to assess self-reported CRC screening behavior. Up-to-date CRC screening was defined as self-reported colonoscopy or sigmoidoscopy in the past 10 years or fecal occult blood testing in the past year. We used multivariable logistic regression to examine the association between gender and self-reported screening, adjusting for covariates. The final model was stratified by gender to examine factors differentially associated with screening outcomes for males and females. The final sample consisted of 1,552 female and 586 male Black Medicare beneficiaries in Baltimore, Maryland. Males were significantly less likely than females to report being up-to-date with screening (77.5% vs. 81.6%, P = 0.030), and this difference was significant in the fully adjusted model (OR: 0.72; 95% confidence interval, 0.52-0.99). The association between having a usual source of care and receipt of cancer screening was stronger among males compared with females. Although observed differences in CRC screening were small, several factors suggest that gender-specific approaches may be used to promote screening adherence among Black Medicare beneficiaries. Given disproportionate CRC mortality between White and Black Medicare beneficiaries, gender-specific interventions aimed at increasing CRC screening may be warranted among older Black patients.
Magklara, Eleni; Burton, Christopher R; Morrison, Val
2014-09-01
To investigate the role of self-efficacy in functional recovery and well-being outcomes in osteoarthritis patients, undergoing hip or knee replacement surgery. Studies were identified using MEDLINE via PUB med, PsycINFO and CINAHL from inception to July 2013. Three search strategies that combined key terms of 'self-efficacy', 'functional recovery', 'well-being' and 'joint replacement' were applied. Titles and abstracts were screened for eligibility and, accordingly, potentially eligible studies were retrieved for review. Included studies were assessed in terms of their quality, and data were extracted by two independent reviewers. A narrative synthesis of results was conducted. In total, 836 articles were identified and after electronic de-duplication, 708 articles remained. After screening 15 articles were retrieved as potentially eligible and eight articles were included in the review. Of the eight studies (n = 967 patients), seven had a prospective design and all studies were considered of good quality. No fully conclusive evidence for the influence of self-efficacy upon functional recovery outcomes was found. When the timing of self-efficacy measurement was examined, post-operative self-efficacy was found to be related to functional recovery outcomes. Presurgical self-efficacy was the least consistent predictor of functional outcomes while postoperative self-efficacy was more consistently associated with recovery outcomes such as longer distance ambulation, exercise repetition and frequency, walking speed and disability. © The Author(s) 2014.
ERIC Educational Resources Information Center
Mayer, Richard E.; Dow, Gayle T.; Mayer, Sarah
2003-01-01
Students learned about electric motors by asking questions and receiving answers from an on-screen pedagogical agent named Dr. Phyz who stood next to an on-screen drawing of an electric motor. Results are consistent with a cognitive theory of multimedia learning and yield principles for the design of interactive multimedia learning environments.…
Low-density homogeneous symmetric nuclear matter: Disclosing dinucleons in coexisting phases
NASA Astrophysics Data System (ADS)
Arellano, Hugo F.; Delaroche, Jean-Paul
2015-01-01
The effect of in-medium dinucleon bound states on self-consistent single-particle fields in Brueckner, Bethe and Goldstone theory is investigated in symmetric nuclear matter at zero temperature. To this end, dinucleon bound state occurences in the 1 S 0 and 3 SD 1 channels are explicitly accounted for --within the continuous choice for the auxiliary fields-- while imposing self-consistency in Brueckner-Hartree-Fock approximation calculations. Searches are carried out at Fermi momenta in the range fm-1, using the Argonne bare nucleon-nucleon potential without resorting to the effective-mass approximation. As a result, two distinct solutions meeting the self-consistency requirement are found with overlapping domains in the interval 0.130 fm-1 0.285 fm-1, corresponding to mass densities between and g cm-3. Effective masses as high as three times the nucleon mass are found in the coexistence domain. The emergence of superfluidity in relationship with BCS pairing gap solutions is discussed.
Correlation energy functional within the GW -RPA: Exact forms, approximate forms, and challenges
NASA Astrophysics Data System (ADS)
Ismail-Beigi, Sohrab
2010-05-01
In principle, the Luttinger-Ward Green’s-function formalism allows one to compute simultaneously the total energy and the quasiparticle band structure of a many-body electronic system from first principles. We present approximate and exact expressions for the correlation energy within the GW -random-phase approximation that are more amenable to computation and allow for developing efficient approximations to the self-energy operator and correlation energy. The exact form is a sum over differences between plasmon and interband energies. The approximate forms are based on summing over screened interband transitions. We also demonstrate that blind extremization of such functionals leads to unphysical results: imposing physical constraints on the allowed solutions (Green’s functions) is necessary. Finally, we present some relevant numerical results for atomic systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kuwahara, Riichi; Accelrys K. K., Kasumigaseki Tokyu Building 17F, 3-7-1 Kasumigaseki, Chiyoda-ku, Tokyo 100-0013; Tadokoro, Yoichi
In this paper, we calculate kinetic and potential energy contributions to the electronic ground-state total energy of several isolated atoms (He, Be, Ne, Mg, Ar, and Ca) by using the local density approximation (LDA) in density functional theory, the Hartree–Fock approximation (HFA), and the self-consistent GW approximation (GWA). To this end, we have implemented self-consistent HFA and GWA routines in our all-electron mixed basis code, TOMBO. We confirm that virial theorem is fairly well satisfied in all of these approximations, although the resulting eigenvalue of the highest occupied molecular orbital level, i.e., the negative of the ionization potential, is inmore » excellent agreement only in the case of the GWA. We find that the wave function of the lowest unoccupied molecular orbital level of noble gas atoms is a resonating virtual bound state, and that of the GWA spreads wider than that of the LDA and thinner than that of the HFA.« less
NASA Astrophysics Data System (ADS)
Almbladh, C.-O.; Morales, A. L.
1989-02-01
Auger CVV spectra of simple metals are generally believed to be well described by one-electron-like theories in the bulk which account for matrix elements and, in some cases, also static core-hole screening effects. We present here detailed calculations on Li, Be, Na, Mg, and Al using self-consistent bulk wave functions and proper matrix elements. The resulting spectra differ markedly from experiment and peak at too low energies. To explain this discrepancy we investigate effects of the surface and dynamical effects of the sudden disappearance of the core hole in the final state. To study core-hole effects we solve Mahan-Nozières-De Dominicis (MND) model numerically over the entire band. The core-hole potential and other parameters in the MND model are determined by self-consistent calculations of the core-hole impurity. The results are compared with simpler approximations based on the final-state rule due to von Barth and Grossmann. To study surface and mean-free-path effects we perform slab calculations for Al but use a simpler infinite-barrier model in the remaining cases. The model reproduces the slab spectra for Al with very good accuracy. In all cases investigated either the effects of the surface or the effects of the core hole give important modifications and a much improved agreement with experiment.
Density-functional energy gaps of solids demystified
NASA Astrophysics Data System (ADS)
Perdew, John P.; Ruzsinszky, Adrienn
2018-06-01
The fundamental energy gap of a solid is a ground-state second energy difference. Can one find the fundamental gap from the gap in the band structure of Kohn-Sham density functional theory? An argument of Williams and von Barth (WB), 1983, suggests that one can. In fact, self-consistent band-structure calculations within the local density approximation or the generalized gradient approximation (GGA) yield the fundamental gap within the same approximation for the energy. Such a calculation with the exact density functional would yield a band gap that also underestimates the fundamental gap, because the exact Kohn-Sham potential in a solid jumps up by an additive constant when one electron is added, and the WB argument does not take this effect into account. The WB argument has been extended recently to generalized Kohn-Sham theory, the simplest way to implement meta-GGAs and hybrid functionals self-consistently, with an exchange-correlation potential that is a non-multiplication operator. Since this operator is continuous, the band gap is again the fundamental gap within the same approximation, but, because the approximations are more realistic, so is the band gap. What approximations might be even more realistic?
Dust trap formation in a non-self-sustained discharge with external gas ionization
DOE Office of Scientific and Technical Information (OSTI.GOV)
Filippov, A. V., E-mail: fav@triniti.ru; Babichev, V. N.; Pal’, A. F.
2015-11-15
Results from numerical studies of a non-self-sustained gas discharge containing micrometer dust grains are presented. The non-self-sustained discharge (NSSD) was controlled by a stationary fast electron beam. The numerical model of an NSSD is based on the diffusion drift approximation for electrons and ions and self-consistently takes into account the influence of the dust component on the electron and ion densities. The dust component is described by the balance equation for the number of dust grains and the equation of motion for dust grains with allowance for the Stokes force, gravity force, and electric force in the cathode sheath. Themore » interaction between dust grains is described in the self-consistent field approximation. The height of dust grain levitation over the cathode is determined and compared with experimental results. It is established that, at a given gas ionization rate and given applied voltage, there is a critical dust grain size above which the levitation condition in the cathode sheath cannot be satisfied. Simulations performed for the dust component consisting of dust grains of two different sizes shows that such grains levitate at different heights, i.e., size separation of dust drains levitating in the cathode sheath of an NSSD takes place.« less
Calculation of Quasi-Particle Energies of Aromatic Self-Assembled Monolayers on Au(111).
Li, Yan; Lu, Deyu; Galli, Giulia
2009-04-14
We present many-body perturbation theory calculations of the electronic properties of phenylene diisocyanide self-assembled monolayers (SAMs) on a gold surface. Using structural models obtained within density functional theory (DFT), we have investigated how the SAM molecular energies are modified by self-energy corrections and how they are affected by the presence of the surface. We have employed a combination of GW (G = Green's function; W = screened Coulomb interaction) calculations of the SAM quasi-particle energies and a semiclassical image potential model to account for surface polarization effects. We find that it is essential to include both quasi-particle corrections and surface screening in order to provide a reasonable estimate of the energy level alignment at a SAM-metal interface. In particular, our results show that within the GW approximation the energy distance between phenylene diisocyanide SAM energy levels and the gold surface Fermi level is much larger than that found within DFT, e.g., more than double in the case of low packing densities of the SAM.
Quantum weak turbulence with applications to semiconductor lasers
NASA Astrophysics Data System (ADS)
Lvov, Yuri Victorovich
Based on a model Hamiltonian appropriate for the description of fermionic systems such as semiconductor lasers, we describe a natural asymptotic closure of the BBGKY hierarchy in complete analogy with that derived for classical weak turbulence. The main features of the interaction Hamiltonian are the inclusion of full Fermi statistics containing Pauli blocking and a simple, phenomenological, uniformly weak two particle interaction potential equivalent to the static screening approximation. The resulting asymytotic closure and quantum kinetic Boltzmann equation are derived in a self consistent manner without resorting to a priori statistical hypotheses or cumulant discard assumptions. We find a new class of solutions to the quantum kinetic equation which are analogous to the Kolmogorov spectra of hydrodynamics and classical weak turbulence. They involve finite fluxes of particles and energy across momentum space and are particularly relevant for describing the behavior of systems containing sources and sinks. We explore these solutions by using differential approximation to collision integral. We make a prima facie case that these finite flux solutions can be important in the context of semiconductor lasers. We show that semiconductor laser output efficiency can be improved by exciting these finite flux solutions. Numerical simulations of the semiconductor Maxwell Bloch equations support the claim.
Self-consistent electrostatic potential due to trapped plasma in the magnetosphere
NASA Technical Reports Server (NTRS)
Miller, Ronald H.; Khazanov, George V.
1993-01-01
A steady state solution for the self-consistent electrostatic potential due to a plasma confined in a magnetic flux tube is considered. A steady state distribution function is constructed for the trapped particles from the constants of the motion, in the absence of waves and collisions. Using Liouville's theorem, the particle density along the geomagnetic field is determined and found to depend on the local magnetic field, self-consistent electric potential, and the equatorial plasma distribution function. A hot anisotropic magnetospheric plasma in steady state is modeled by a bi-Maxwellian at the equator. The self-consistent electric potential along the magnetic field is calculated assuming quasineutrality, and the potential drop is found to be approximately equal to the average kinetic energy of the equatorially trapped plasma. The potential is compared with that obtained by Alfven and Faelthammar (1963).
Chowdhury, Rupak; David, Nganwa; Bogale, Asseged; Nandy, Shami; Habtemariam, T.; Tameru, Berhanu
2016-01-01
PURPOSE: African-American (AA) women living in four Black Belt Counties (BBC) of Alabama; consisting of Barbour, Macon, Green and Wilcox are known to have lower mammogram utilization and breast self-exam rates when compared to their white female counterparts. The influence of socioeconomic and demographic factors on these disparities has not been clearly defined so far. Our study was designed to determine whether these observed disparities can be predicted with the socioeconomic and other demographic attributes. METHODS: Health Disparity Questionnaires data (n = 516) for BBC of Alabama was analyzed using a logistic regression model to examine the association of breast cancer screening rates and breast self-exam with income, the level of education, family doctor, type of health insurance, obesity, and age. RESULTS: Income, education, family doctor, age and health insurance were independent predictors for the low utilization rate of mammography and breast self-exam (BSE). CONCLUSION: Improving socioeconomic conditions such as level of education and availability of health care are essential to increase the rates of breast cancer screening test and breast self-exam in the BBC of Alabama. PMID:26958089
ERIC Educational Resources Information Center
Bayraktar, Hatice Vatansever
2016-01-01
The aim of this study is to examine the levels of the self-efficacy of primary school teacher candidates towards first reading-writing education and whether they differentiate by various variables. The study is prepared in accordance with the screening model. The universe of this study consists of the primary school teacher candidates who receive…
Kim, H S; Kim, E; Kim, J W
2001-04-01
Internet-based health information will enable us to interact with many people despite distance and time constraints. Informational media by computer is expected to become an important factor that affects health behavior. This study was done to develop an accessible multimedia program about breast self-examination on the Internet. This study was designed by using the two steps of need assessment and program development. For the need assessment step, a survey was carried out. The sample consisted of the 82 women of Yonsei University selected by convenient random sampling. At the program development step, screen design took into account perspectives of computer engineering. A storyboard for every screen was made via screen design and then ported to computer using the Netscape Navigator program. A breast self-examination program was developed using Netscape 4.0 on the Windows 98 platform. The multimedia program, including text, graphics, animation, and sound, was constructed with HTML language using Memo Sheet in Netscape Navigator. The contents of health information posted on the Internet included general information about breast cancer, the importance of breast self-examination, self-risk appraisal of breast cancer, the diverse methods about breast self-examination, the monthly check list graph, and social network for consultation. It is possible to interact with clients through the Question and Answer function on screen. This Internet-based health information program provides enough information, which can be accessed using search systems on the Internet.
Self-consistent models for Coulomb heated X-ray pulsar atmospheres
NASA Technical Reports Server (NTRS)
Harding, A.; Meszaros, S. P.; Kirk, J.; Galloway, D.
1983-01-01
Calculations of accreting magnetized neutron star atmospheres heated by the gradual deceleration of protons via Coulomb collisions are presented. Self consistent determinations of the temperature and density structure for different accretion rates are made by assuming hydrostatic equilibrium and energy balance, coupled with radiative transfer. The full radiative transfer in two polarizations, using magnetic cross sections but with cyclotron resonance effects treated approximately, is carried out in the inhomogeneous atmospheres.
Short- and long-time diffusion and dynamic scaling in suspensions of charged colloidal particles
NASA Astrophysics Data System (ADS)
Banchio, Adolfo J.; Heinen, Marco; Holmqvist, Peter; Nägele, Gerhard
2018-04-01
We report on a comprehensive theory-simulation-experimental study of collective and self-diffusion in concentrated suspensions of charge-stabilized colloidal spheres. In theory and simulation, the spheres are assumed to interact directly by a hard-core plus screened Coulomb effective pair potential. The intermediate scattering function, fc(q, t), is calculated by elaborate accelerated Stokesian dynamics (ASD) simulations for Brownian systems where many-particle hydrodynamic interactions (HIs) are fully accounted for, using a novel extrapolation scheme to a macroscopically large system size valid for all correlation times. The study spans the correlation time range from the colloidal short-time to the long-time regime. Additionally, Brownian Dynamics (BD) simulation and mode-coupling theory (MCT) results of fc(q, t) are generated where HIs are neglected. Using these results, the influence of HIs on collective and self-diffusion and the accuracy of the MCT method are quantified. It is shown that HIs enhance collective and self-diffusion at intermediate and long times. At short times self-diffusion, and for wavenumbers outside the structure factor peak region also collective diffusion, are slowed down by HIs. MCT significantly overestimates the slowing influence of dynamic particle caging. The dynamic scattering functions obtained in the ASD simulations are in overall good agreement with our dynamic light scattering (DLS) results for a concentration series of charged silica spheres in an organic solvent mixture, in the experimental time window and wavenumber range. From the simulation data for the time derivative of the width function associated with fc(q, t), there is indication of long-time exponential decay of fc(q, t), for wavenumbers around the location of the static structure factor principal peak. The experimental scattering functions in the probed time range are consistent with a time-wavenumber factorization scaling behavior of fc(q, t) that was first reported by Segrè and Pusey [Phys. Rev. Lett. 77, 771 (1996)] for suspensions of hard spheres. Our BD simulation and MCT results predict a significant violation of exact factorization scaling which, however, is approximately restored according to the ASD results when HIs are accounted for, consistent with the experimental findings for fc(q, t). Our study of collective diffusion is amended by simulation and theoretical results for the self-intermediate scattering function, fs(q, t), and its non-Gaussian parameter α2(t) and for the particle mean squared displacement W(t) and its time derivative. Since self-diffusion properties are not assessed in standard DLS measurements, a method to deduce W(t) approximately from fc(q, t) is theoretically validated.
Levy, Boaz; Celen-Demirtas, Selda; Surguladze, Tinatin; Eranio, Sara; Ellison, James
2014-03-30
Cost-prohibitive factors currently prevent a warranted integration of neuropsychological screenings into routine psychiatric evaluations, as a standard of care. To overcome this challenge, the current study examined the psychometric properties of a new computerized measure-the CNS Screen. One hundred and twenty six psychiatric inpatients completed the CNS Screen, the Montreal Cognitive Assessment (MoCA), and the Quick Inventory of Depressive Symptomatology-Self Rated (QIDS-SR₁₆) on the day of hospital discharge. Statistical analysis established convergent validity with a moderate correlation between the self-administered CNS Screen and the clinician-administered MoCA (r=0.64). Discriminant validity was implicated by a non-significant correlation with the QIDS-SR₁₆. Concurrent validity was supported by a moderate, negative correlation with patients' age (r=-0.62). In addition, consistent with previous findings, patients with psychotic disorders exhibited significantly poorer performance on the CNS Screen than patients with a mood disorder. Similarly, patients with a formal disability status scored significantly lower than other patients. The CNS Screen was well tolerated by all patients. With further development, this type of measure may provide a cost-effective approach to expanding neuropsychological screenings on inpatient psychiatric units. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Finzel, Kati, E-mail: kati.finzel@liu.se
The local conditions for the Pauli potential that are necessary in order to yield self-consistent electron densities from orbital-free calculations are investigated for approximations that are expressed with the help of a local position variable. It is shown that those local conditions also apply when the Pauli potential is given in terms of the electron density. An explicit formula for the Ne atom is given, preserving the local conditions during the iterative procedure. The resulting orbital-free electron density exhibits proper shell structure behavior and is in close agreement with the Kohn-Sham electron density. This study demonstrates that it is possiblemore » to obtain self-consistent orbital-free electron densities with proper atomic shell structure from simple one-point approximations for the Pauli potential at local density level.« less
Exploring the limits of the self-consistent Born approximation for inelastic electronic transport
NASA Astrophysics Data System (ADS)
Lee, William; Jean, Nicola; Sanvito, Stefano
2009-02-01
The nonequilibrium Green’s function formalism is today the standard computational method for describing elastic transport in molecular devices. This can be extended to include inelastic scattering by the so-called self-consistent Born approximation (SCBA), where the interaction of the electrons with the vibrations of the molecule is assumed to be weak and it is treated perturbatively. The validity of such assumption and therefore of the SCBA is difficult to establish with certainty. In this work we explore the limitations of the SCBA by using a simple tight-binding model with the electron-phonon coupling strength α chosen as a free parameter. As model devices we consider Au monatomic chains and a H2 molecule sandwiched between Pt electrodes. In both cases, our self-consistent calculations demonstrate a breakdown of the SCBA for large α and we identify a weak and a strong-coupling regime. For weak coupling our SCBA results compare closely with those obtained with exact scattering theory. However in the strong-coupling regime large deviations are found. In particular we demonstrate that there is a critical coupling strength, characteristic of the materials system, beyond which multiple self-consistent solutions can be found depending on the initial conditions in the simulation. These are entirely due to the large contribution of the Hartree self-energy and completely disappear when this is neglected. We attribute this feature to the breakdown of the perturbative expansion leading to the SCBA.
2014-01-01
Background Active, population-wide mass screening and treatment (MSAT) for chronic Plasmodium falciparum carriage to eliminate infectious reservoirs of malaria transmission have proven difficult to apply on large national scales through trained clinicians from central health authorities. Methodology Fourteen population clusters of approximately 1,000 residents centred around health facilities (HF) in two rural Zambian districts were each provided with three modestly remunerated community health workers (CHWs) conducting active monthly household visits to screen and treat all consenting residents for malaria infection with rapid diagnostic tests (RDT). Both CHWs and HFs also conducted passive case detection among residents who self-reported for screening and treatment. Results Diagnostic positivity was higher among symptomatic patients self-reporting to CHWs (42.5%) and HFs (24%) than actively screened residents (20.3%), but spatial and temporal variations of diagnostic positivity were highly consistent across all three systems. However, most malaria infections (55.6%) were identified through active home visits by CHWs rather than self-reporting to CHWs or HFs. Most (62%) malaria infections detected actively by CHWs reported one or more symptoms of illness. Most reports of fever and vomiting, plus more than a quarter of history of fever, headache and diarrhoea, were attributable to malaria infection. The minority of residents who participated >12 times had lower rates of malaria infection and associated symptoms in later contacts but most residents were tested <4 times and high malaria diagnostic positivity (32%) in active surveys, as well as incidence (1.7 detected infections per person per year) persisted in the population. Per capita cost for active service delivery by CHWs was US$5.14 but this would rise to US$10.68 with full community compliance with monthly testing at current levels of transmission, and US$6.25 if pre-elimination transmission levels and negligible treatment costs were achieved. Conclusion Monthly active home visits by CHWs equipped with RDTs were insufficient to eliminate the human infection reservoir in this typical African setting, despite reasonably high LLIN/IRS coverage. However, dramatic impact upon infection and morbidity burden might be attainable and cost-effective if community participation in regular testing could be improved and the substantial, but not necessarily prohibitive, costs are affordable to national programmes. PMID:24678631
Justifying quasiparticle self-consistent schemes via gradient optimization in Baym-Kadanoff theory.
Ismail-Beigi, Sohrab
2017-09-27
The question of which non-interacting Green's function 'best' describes an interacting many-body electronic system is both of fundamental interest as well as of practical importance in describing electronic properties of materials in a realistic manner. Here, we study this question within the framework of Baym-Kadanoff theory, an approach where one locates the stationary point of a total energy functional of the one-particle Green's function in order to find the total ground-state energy as well as all one-particle properties such as the density matrix, chemical potential, or the quasiparticle energy spectrum and quasiparticle wave functions. For the case of the Klein functional, our basic finding is that minimizing the length of the gradient of the total energy functional over non-interacting Green's functions yields a set of self-consistent equations for quasiparticles that is identical to those of the quasiparticle self-consistent GW (QSGW) (van Schilfgaarde et al 2006 Phys. Rev. Lett. 96 226402-4) approach, thereby providing an a priori justification for such an approach to electronic structure calculations. In fact, this result is general, applies to any self-energy operator, and is not restricted to any particular approximation, e.g., the GW approximation for the self-energy. The approach also shows that, when working in the basis of quasiparticle states, solving the diagonal part of the self-consistent Dyson equation is of primary importance while the off-diagonals are of secondary importance, a common observation in the electronic structure literature of self-energy calculations. Finally, numerical tests and analytical arguments show that when the Dyson equation produces multiple quasiparticle solutions corresponding to a single non-interacting state, minimizing the length of the gradient translates into choosing the solution with largest quasiparticle weight.
Moran, Ryan N; Covassin, Tracey; Elbin, R J; Gould, Dan; Nogle, Sally
2018-05-01
The Vestibular/Ocular Motor Screening (VOMS) measure is a newly developed vestibular and ocular motor symptom provocation screening tool for sport-related concussions. Baseline data, psychometric properties, and reliability of the VOMS are needed to further understand the applications of this tool, especially in the youth population, where research is scarce. To establish normative data and document the internal consistency and false-positive rate of the VOMS in a sample of nonconcussed youth athletes. Cross-sectional study; Level of evidence, 3. A total of 423 youth athletes (male = 278, female = 145) between the ages of 8 and 14 years completed baseline VOMS screening before the start of their respective sport seasons. Internal consistency was measured with Cronbach α and inter-item correlations. Approximately 60% of youth athletes reported no symptom provocation on baseline VOMS assessment, with 9% to 13% scoring over the cutoff levels (score of ≥2 for any individual VOMS symptom, near point convergence distance of ≥5 cm). The VOMS displayed a high internal consistency (Cronbach α = .97) at baseline among youth athletes. The current findings provide preliminary support for the implementation of VOMS baseline assessment into clinical practice, due to a high internal consistency, strong relationships between VOMS items, and a low false-positive rate at baseline in youth athletes.
Confirmatory factor analysis of the Chinese Breast Cancer Screening Beliefs Questionnaire.
Kwok, Cannas; Fethney, Judith; White, Kate
2012-01-01
Chinese women have been consistently reported as having low breast cancer screening practices. The Chinese Breast Cancer Screening Beliefs Questionnaire (CBCSB) was designed to assess Chinese Australian women's beliefs, knowledge, and attitudes toward breast cancer and screening practices. The objectives of the study were to confirm the factor structure of the CBCSB with a new, larger sample of immigrant Chinese Australian women and to report its clinical validity. A convenience sample of 785 Chinese Australian women was recruited from Chinese community organizations and shopping malls. Cronbach α was used to assess internal consistency reliability, and Amos v18 was used for confirmatory factor analysis. Clinical validity was assessed through linear regression using SPSS v18. The 3-factor structure of the CBCSB was confirmed, although the model required respecification to arrive at a suitable model fit as measured by the goodness-of-fit index (0.98), adjusted goodness-of-fit index (0.97), normed fit index (0.95), and root mean square error of approximation (0.031). Internal consistency reliability coefficients were satisfactory (>.6). Women who engaged in all 3 types of screening had more proactive attitudes to health checkups and perceived less barriers to mammographic screening. The CBCSB is a valid and reliable tool for assessing Chinese women's beliefs, knowledge, and attitudes about breast cancer and breast cancer screening practices. The CBCSB can be used for providing practicing nurses with insights into the provision of culturally sensitive breast health education.
Neradilek, Moni B.; Polissar, Nayak L.; Einstein, Daniel R.; Glenny, Robb W.; Minard, Kevin R.; Carson, James P.; Jiao, Xiangmin; Jacob, Richard E.; Cox, Timothy C.; Postlethwait, Edward M.; Corley, Richard A.
2017-01-01
We examine a previously published branch-based approach for modeling airway diameters that is predicated on the assumption of self-consistency across all levels of the tree. We mathematically formulate this assumption, propose a method to test it and develop a more general model to be used when the assumption is violated. We discuss the effect of measurement error on the estimated models and propose methods that take account of error. The methods are illustrated on data from MRI and CT images of silicone casts of two rats, two normal monkeys, and one ozone-exposed monkey. Our results showed substantial departures from self-consistency in all five subjects. When departures from self-consistency exist, we do not recommend using the self-consistency model, even as an approximation, as we have shown that it may likely lead to an incorrect representation of the diameter geometry. The new variance model can be used instead. Measurement error has an important impact on the estimated morphometry models and needs to be addressed in the analysis. PMID:22528468
Nonequilibrium self-energy functional theory
NASA Astrophysics Data System (ADS)
Hofmann, Felix; Eckstein, Martin; Arrigoni, Enrico; Potthoff, Michael
2013-10-01
The self-energy functional theory (SFT) is generalized to describe the real-time dynamics of correlated lattice-fermion models far from thermal equilibrium. This is achieved by starting from a reformulation of the original equilibrium theory in terms of double-time Green's functions on the Keldysh-Matsubara contour. With the help of a generalized Luttinger-Ward functional, we construct a functional Ω̂[Σ] which is stationary at the physical (nonequilibrium) self-energy Σ and which yields the grand potential of the initial thermal state Ω at the physical point. Nonperturbative approximations can be defined by specifying a reference system that serves to generate trial self-energies. These self-energies are varied by varying the reference system's one-particle parameters on the Keldysh-Matsubara contour. In the case of thermal equilibrium, this approach reduces to the conventional SFT. Contrary to the equilibrium theory, however, “unphysical” variations, i.e., variations that are different on the upper and the lower branches of the Keldysh contour, must be considered to fix the time dependence of the optimal physical parameters via the variational principle. Functional derivatives in the nonequilibrium SFT Euler equation are carried out analytically to derive conditional equations for the variational parameters that are accessible to a numerical evaluation via a time-propagation scheme. Approximations constructed by means of the nonequilibrium SFT are shown to be inherently causal, internally consistent, and to respect macroscopic conservation laws resulting from gauge symmetries of the Hamiltonian. This comprises the nonequilibrium dynamical mean-field theory but also dynamical-impurity and variational-cluster approximations that are specified by reference systems with a finite number of degrees of freedom. In this way, nonperturbative and consistent approximations can be set up, the numerical evaluation of which is accessible to an exact-diagonalization approach.
Influence of scattering processes on electron quantum states in nanowires
Galenchik, Vadim; Borzdov, Andrei; Borzdov, Vladimir; Komarov, Fadei
2007-01-01
In the framework of quantum perturbation theory the self-consistent method of calculation of electron scattering rates in nanowires with the one-dimensional electron gas in the quantum limit is worked out. The developed method allows both the collisional broadening and the quantum correlations between scattering events to be taken into account. It is an alternativeper seto the Fock approximation for the self-energy approach based on Green’s function formalism. However this approach is free of mathematical difficulties typical to the Fock approximation. Moreover, the developed method is simpler than the Fock approximation from the computational point of view. Using the approximation of stable one-particle quantum states it is proved that the electron scattering processes determine the dependence of electron energy versus its wave vector.
Thombs, Brett D; Saadat, Nazanin; Riehm, Kira E; Karter, Justin Michael; Vaswani, Akansha; Andrews, Bonnie K; Simons, Peter; Cosgrove, Lisa
2017-08-09
Recently, health screening recommendations have gone beyond screening for early-stage, asymptomatic disease to include "screening" for presently experienced health problems and symptoms using self-report questionnaires. We examined recommendations from three major national guideline organizations to determine the consistency of recommendations, identify sources of divergent recommendations, and determine if guideline organizations have identified any direct randomized controlled trial (RCT) evidence for the effectiveness of questionnaire-based screening. We reviewed recommendation statements listed by the Canadian Task Force on Preventive Health Care (CTFPHC), the United Kingdom National Screening Committee (UKNSC), and the United States Preventive Services Task Force (USPSTF) as of 5 September 2016. Eligible recommendations focused on using self-report questionnaires to identify patients with presently experienced health problems or symptoms. Within each recommendation and accompanying evidence review we identified screening RCTs. We identified 22 separate recommendations on questionnaire-based screening, including three CTFPHC recommendations against screening, eight UKNSC recommendations against screening, four USPSTF recommendations in favor of screening (alcohol misuse, adolescent depression, adult depression, intimate partner violence), and seven USPSTF recommendations that did not recommend for or against screening. In the four cases where the USPSTF recommended screening, either the CTFPHC, the UKNSC, or both recommended against. When recommendations diverged, the USPSTF expressed confidence in benefits based on indirect evidence, evaluated potential harms as minimal, and did not consider cost or resource use. CTFPHC and UKNSC recommendations against screening, on the other hand, focused on the lack of direct evidence of benefit and raised concerns about harms to patients and resource use. Of six RCTs that directly evaluated screening interventions, five did not report any statistically significant primary or secondary health outcomes in favor of screening, and one trial reported equivocal results. Only the USPSTF has made any recommendations for screening with questionnaires for presently experienced problems or symptoms. The CTFPHC and UKNSC recommended against screening in all of their recommendations. Differences in recommendations appear to reflect differences in willingness to assume benefit from indirect evidence and different approaches to assessing possible harms and resource consumption. There were no examples in any recommendations of RCTs with direct evidence of improved health outcomes.
Testing strong-segregation theory against self-consistent-field theory for block copolymer melts
NASA Astrophysics Data System (ADS)
Matsen, M. W.
2001-06-01
We introduce a highly efficient self-consistent-field theory (SCFT) method for examining the cylindrical and spherical block copolymer morphologies using a standard unit cell approximation (UCA). The method is used to calculate the classical diblock copolymer phase boundaries deep into the strong-segregation regime, where they can be compared with recent improvements to strong-segregation theory (SST). The comparison suggests a significant discrepancy between the two theories indicating that our understanding of strongly stretched polymer brushes is still incomplete.
Self-consistent models for Coulomb-heated X-ray pulsar atmospheres
NASA Technical Reports Server (NTRS)
Harding, A. K.; Kirk, J. G.; Galloway, D. J.; Meszaros, P.
1984-01-01
Calculations of accreting magnetized neutron star atmospheres heated by the gradual deceleration of Protons via Coulomb collisions are presented. Self consistent determinations of the temperature and density structure for different accretion rates are made by assuming hydrostatic equilibrium and energy balance, coupled with radiative transfer. The full radiative transfer in two polarizations, using magnetic cross sections but with cyclotron resonance effects treated approximately, is carried out in the inhomogeneous atmospheres. Previously announced in STAR as N84-12012
Self-consistent mean-field approach to the statistical level density in spherical nuclei
NASA Astrophysics Data System (ADS)
Kolomietz, V. M.; Sanzhur, A. I.; Shlomo, S.
2018-06-01
A self-consistent mean-field approach within the extended Thomas-Fermi approximation with Skyrme forces is applied to the calculations of the statistical level density in spherical nuclei. Landau's concept of quasiparticles with the nucleon effective mass and the correct description of the continuum states for the finite-depth potentials are taken into consideration. The A dependence and the temperature dependence of the statistical inverse level-density parameter K is obtained in a good agreement with experimental data.
Reiner, A; Høye, J S
2005-12-01
The hierarchical reference theory and the self-consistent Ornstein-Zernike approximation are two liquid state theories that both furnish a largely satisfactory description of the critical region as well as phase coexistence and the equation of state in general. Furthermore, there are a number of similarities that suggest the possibility of a unification of both theories. As a first step towards this goal, we consider the problem of combining the lowest order gamma expansion result for the incorporation of a Fourier component of the interaction with the requirement of consistency between internal and free energies, leaving aside the compressibility relation. For simplicity, we restrict ourselves to a simplified lattice gas that is expected to display the same qualitative behavior as more elaborate models. It turns out that the analytically tractable mean spherical approximation is a solution to this problem, as are several of its generalizations. Analysis of the characteristic equations shows the potential for a practical scheme and yields necessary conditions that any closure to the Ornstein-Zernike relation must fulfill for the consistency problem to be well posed and to have a unique differentiable solution. These criteria are expected to remain valid for more general discrete and continuous systems, even if consistency with the compressibility route is also enforced where possible explicit solutions will require numerical evaluations.
Liao, Peilin; Carter, Emily A
2011-09-07
Quantitative characterization of low-lying excited electronic states in materials is critical for the development of solar energy conversion materials. The many-body Green's function method known as the GW approximation (GWA) directly probes states corresponding to photoemission and inverse photoemission experiments, thereby determining the associated band structure. Several versions of the GW approximation with different levels of self-consistency exist in the field. While the GWA based on density functional theory (DFT) works well for conventional semiconductors, less is known about its reliability for strongly correlated semiconducting materials. Here we present a systematic study of the GWA using hematite (α-Fe(2)O(3)) as the benchmark material. We analyze its performance in terms of the calculated photoemission/inverse photoemission band gaps, densities of states, and dielectric functions. Overall, a non-self-consistent G(0)W(0) using input from DFT+U theory produces physical observables in best agreement with experiments. This journal is © the Owner Societies 2011
Liang, Y Y; Chen, H; Mizuseki, H; Kawazoe, Y
2011-04-14
We use density functional theory based nonequilibrium Green's function to self-consistently study the current through the 1,4-benzenedithiol (BDT). The elastic and inelastic tunneling properties through this Au-BDT-Au molecular junction are simulated, respectively. For the elastic tunneling case, it is found that the current through the tilted molecule can be modulated effectively by the external gate field, which is perpendicular to the phenyl ring. The gate voltage amplification comes from the modulation of the interaction between the electrodes and the molecules in the junctions. For the inelastic case, the electron tunneling scattered by the molecular vibrational modes is considered within the self-consistent Born approximation scheme, and the inelastic electron tunneling spectrum is calculated.
The closure approximation in the hierarchy equations.
NASA Technical Reports Server (NTRS)
Adomian, G.
1971-01-01
The expectation of the solution process in a stochastic operator equation can be obtained from averaged equations only under very special circumstances. Conditions for validity are given and the significance and validity of the approximation in widely used hierarchy methods and the ?self-consistent field' approximation in nonequilibrium statistical mechanics are clarified. The error at any level of the hierarchy can be given and can be avoided by the use of the iterative method.
Health Literacy and Cancer Prevention: Two New Instruments to Assess Comprehension
Mazor, Kathleen M.; Roblin, Douglas W.; Williams, Andrew E.; Greene, Sarah M.; Gaglio, Bridget; Field, Terry S.; Costanza, Mary E.; Han, Paul K. J.; Saccoccio, Laura; Calvi, Josephine; Cove, Erica; Cowan, Rebecca
2012-01-01
Objectives Ability to understand spoken health information is an important facet of health literacy, but to date, no instrument has been available to quantify patients’ ability in this area. We sought to develop a test to assess comprehension of spoken health messages related to cancer prevention and screening to fill this gap, and a complementary test of comprehension of written health messages. Methods We used the Sentence Verification Technique to write items based on realistic health messages about cancer prevention and screening, including media messages, clinical encounters and clinical print materials. Items were reviewed, revised, and pre-tested. Adults aged 40 to 70 participated in a pilot administration in Georgia, Hawaii, and Massachusetts. Results The Cancer Message Literacy Test-Listening is self-administered via touchscreen laptop computer. No reading is required. It takes approximately 1 hour. The Cancer Message Literacy Test-Reading is self-administered on paper. It takes approximately 10 minutes. Conclusions These two new tests will allow researchers to assess comprehension of spoken health messages, to examine the relationship between listening and reading literacy, and to explore the impact of each form of literacy on health-related outcomes. Practice Implications Researchers and clinicians now have a means of measuring comprehension of spoken health information. PMID:22244323
NASA Astrophysics Data System (ADS)
Ghaderzadeh, A.; Rahbari, S. H. Ebrahimnazhad; Phirouznia, A.
2018-03-01
In this study, Rashba coupling induced Aharonov-Casher effect in a graphene based nano ring is investigated theoretically. The graphene based nano ring is considered as a central device connected to semi-infinite graphene nano ribbons. In the presence of the Rashba spin-orbit interaction, two armchair shaped edge nano ribbons are considered as semi-infinite leads. The non-equilibrium Green's function approach is utilized to obtain the quantum transport characteristics of the system. The relaxation and dephasing mechanisms within the self-consistent Born approximation is scrutinized. The Lopez-Sancho method is also applied to obtain the self-energy of the leads. We unveil that the non-equilibrium current of the system possesses measurable Aharonov-Casher oscillations with respect to the Rashba coupling strength. In addition, we have observed the same oscillations in dilute impurity regimes in which amplitude of the oscillations is shown to be suppressed as a result of the relaxations.
Smollon, William E; Wooten, Billy R; Hammond, Billy R
2015-11-01
Heterochromatic flicker photometry (HFP) is commonly used to determine macular pigment optical density (MPOD). Since HFP in this application is a locus comparison method, an identical relative spectral response at each locus is required for a perfect measure. We know this requirement cannot be strictly true since the optical density of photopigments increases as the foveal center is approached. Thus, the self-screening effect would result in an underestimate of MPOD. An earlier study concluded that the underestimate is on the order of 30%. We examined this issue by manipulating photopigment optical density, and consequently the degree of selfscreening. A continuously exposed, 470 nm, background bleached cone photopigments over a range from 0 to 80%. MPOD was determined 10' and 30' from the foveal center. Two subjects were used in the main experiment. Five additional subjects were studied with just the 0% and 80% bleach levels. Spectral measures were obtained at 0% and 70% bleach levels for the two primary subjects. Subjects in the main experiment showed MPOD estimates that increased with increasing bleaching. The effect, however, was small: one observer's MPOD increased 0.08 and 0.02 for the 10' and 30' loci, respectively; the other observer's values were 0.04 and 0.01 for the same loci. Comparable values were obtained for the other five subjects using the 0% and 80% bleach conditions. Spectral measures were consistent with the findings of the main experiment. When self-screening is nearly abolished (80% bleach), a relatively small underestimation is revealed for the unbleached state. For the 1° target we show about 2-3% underestimation. Our 20' target reveals a larger underestimate (8-9%), consistent with longer photoreceptor outer-segments nearer the foveal center. We conclude that HFP yields values essentially independent of self-screening for targets of 1° diameter or greater. Smaller targets are less than 10% underestimated for near-zero bleach conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.
Approximate scaling properties of RNA free energy landscapes
NASA Technical Reports Server (NTRS)
Baskaran, S.; Stadler, P. F.; Schuster, P.
1996-01-01
RNA free energy landscapes are analysed by means of "time-series" that are obtained from random walks restricted to excursion sets. The power spectra, the scaling of the jump size distribution, and the scaling of the curve length measured with different yard stick lengths are used to describe the structure of these "time series". Although they are stationary by construction, we find that their local behavior is consistent with both AR(1) and self-affine processes. Random walks confined to excursion sets (i.e., with the restriction that the fitness value exceeds a certain threshold at each step) exhibit essentially the same statistics as free random walks. We find that an AR(1) time series is in general approximately self-affine on timescales up to approximately the correlation length. We present an empirical relation between the correlation parameter rho of the AR(1) model and the exponents characterizing self-affinity.
Total Body Photography as an Aid to Skin Self-examination: A Patient's Perspective.
Secker, Lisanne J; Bergman, Wilma; Kukutsch, Nicole A
2016-02-01
Skin self-examination can help patients who are at high risk for developing melanoma to become more involved in their own surveillance and treatment. This study examined the use of total body photography as an aid to skin self-examination from the patients' perspective. A total of 179 individuals at high risk for developing melanoma who had undergone total body photography (60.5% response rate) completed a self-reported questionnaire assessing the frequency of skin self-examination, perceived usefulness of total body photography, and a variety of potential demographic, clinical and psychological factors. Only approximately half of the participants indicated skin self-examination as useful and 78.9% preferred clinical skin examination by a specialist. Finding total body photography useful was associated with having received instructions on how to perform skin self-examination, the use of a (hand)mirror, and confidence to detect changing moles. These findings allow us to develop strategies to further improve patients' self-screening behaviours.
Conduction in fully ionized liquid metals
NASA Technical Reports Server (NTRS)
Stevenson, D. J.; Ashcroft, N. W.
1973-01-01
Electron transport is considered in high density fully ionized liquid metals. Ionic structure is described in terms of hard-sphere correlation functions and the scattering is determined from self-consistently screened point ions. Applications to the physical properties of the deep interior of Jupiter are briefly considered.
Self-consistent treatment of electrostatics in molecular DNA braiding through external forces.
Lee, Dominic J
2014-06-01
In this paper we consider a physical system in which two DNA molecules braid about each other. The distance between the two molecular ends, on either side of the braid, is held at a distance much larger than supercoiling radius of the braid. The system is subjected to an external pulling force, and a moment that induces the braiding. In a model, developed for understanding such a system, we assume that each molecule can be divided into a braided and unbraided section. We also suppose that the DNA is nicked so that there is no constraint of the individual linking numbers of the molecules. Included in the model are steric and electrostatic interactions, thermal fluctuations of the braided and unbraided sections of the molecule, as well as the constraint on the braid linking (catenation) number. We compare two approximations used in estimating the free energy of the braided section. One is where the amplitude of undulations of one molecule with respect to the other is determined only by steric interactions. The other is a self-consistent determination of the mean-squared amplitude of these undulations. In this second approximation electrostatics should play an important role in determining this quantity, as suggested by physical arguments. We see that if the electrostatic interaction is sufficiently large there are indeed notable differences between the two approximations. We go on to test the self-consistent approximation-included in the full model-against experimental data for such a system, and we find good agreement. However, there seems to be a slight left-right-handed braid asymmetry in some of the experimental results. We discuss what might be the origin of this small asymmetry.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brinckmann, Jan; Woelfle, Peter
2004-11-01
The nearest-neighbor quantum antiferromagnetic (AF) Heisenberg model for spin-1/2 on a two-dimensional square lattice is studied in the auxiliary-fermion representation. Expressing spin operators by canonical fermionic particles requires a constraint on the fermion charge Q{sub i}=1 on each lattice site i, which is imposed approximately through the thermal average. The resulting interacting fermion system is first treated in mean-field theory (MFT), which yields an AF ordered ground state and spin waves in quantitative agreement with conventional spin-wave theory. At finite temperature a self-consistent approximation beyond mean field is required in order to fulfill the Mermin-Wagner theorem. We first discuss amore » fully self-consistent approximation, where fermions are renormalized due to fluctuations of their spin density, in close analogy to FLEX. While static properties like the correlation length, {xi}(T){proportional_to}exp(aJ/T), come out correctly, the dynamical response lacks the magnon-like peaks which would reflect the appearance of short-range order at low T. This drawback, which is caused by overdamping, is overcome in a 'minimal self-consistent approximation' (MSCA), which we derive from the equations of motion. The MSCA features dynamical scaling at small energy and temperature and is qualitatively correct both in the regime of order-parameter relaxation at long wavelengths {lambda}>{xi} and in the short-range-order regime at {lambda}<{xi}. We also discuss the impact of vertex corrections and the problem of pseudo-gap formation in the single-particle density of states due to long-range fluctuations. Finally we show that the (short-range) magnetic order in MFT and MSCA helps to fulfill the constraint on the local fermion occupancy.« less
Self-control over combined video feedback and modeling facilitates motor learning.
Post, Phillip G; Aiken, Christopher A; Laughlin, David D; Fairbrother, Jeffrey T
2016-06-01
Allowing learners to control the video presentation of knowledge of performance (KP) or an expert model during practice has been shown to facilitate motor learning (Aiken, Fairbrother, & Post, 2012; Wulf, Raupach, & Pfeiffer, 2005). Split-screen replay features now allow for the simultaneous presentation of these modes of instructional support. It is uncertain, however, if such a combination incorporated into a self-control protocol would yield similar benefits seen in earlier self-control studies. Therefore, the purpose of the present study was to examine the effects of self-controlled split-screen replay on the learning of a golf chip shot. Participants completed 60 practice trials, three administrations of the Intrinsic Motivation Inventory, and a questionnaire on day one. Retention and transfer tests and a final motivation inventory were completed on day two. Results revealed significantly higher form and accuracy scores for the self-control group during transfer. The self-control group also had significantly higher scores on the perceived competence subscale, reported requesting feedback mostly after perceived poor trials, and recalled a greater number of critical task features compared to the yoked group. The findings for the performance measures were consistent with previous self-control research. Copyright © 2016 Elsevier B.V. All rights reserved.
Dynamics and Self-consistent Chaos in a Mean Field Hamiltonian Model
NASA Astrophysics Data System (ADS)
del-Castillo-Negrete, Diego
We study a mean field Hamiltonian model that describes the collective dynamics of marginally stable fluids and plasmas in the finite N and N-> infty kinetic limit (where N is the number of particles). The linear stability of equilibria in the kinetic model is studied as well as the initial value problem including Landau damping . Numerical simulations show the existence of coherent, rotating dipole states. We approximate the dipole as two macroparticles and show that the N=2 limit has a family of rotating integrable solutions that provide an accurate description of the dynamics. We discuss the role of self-consistent Hamiltonian chaos in the formation of coherent structures, and discuss a mechanism of "violent" mixing caused by a self-consistent elliptic-hyperbolic bifurcation in phase space.
Solvent effects in time-dependent self-consistent field methods. I. Optical response calculations
Bjorgaard, J. A.; Kuzmenko, V.; Velizhanin, K. A.; ...
2015-01-22
In this study, we implement and examine three excited state solvent models in time-dependent self-consistent field methods using a consistent formalism which unambiguously shows their relationship. These are the linear response, state specific, and vertical excitation solvent models. Their effects on energies calculated with the equivalent of COSMO/CIS/AM1 are given for a set of test molecules with varying excited state charge transfer character. The resulting solvent effects are explained qualitatively using a dipole approximation. It is shown that the fundamental differences between these solvent models are reflected by the character of the calculated excitations.
NASA Astrophysics Data System (ADS)
Nahar, S. N.
2003-01-01
Most astrophysical plasmas entail a balance between ionization and recombination. We present new results from a unified method for self-consistent and ab initio calculations for the inverse processes of photoionization and (e + ion) recombination. The treatment for (e + ion) recombination subsumes the non-resonant radiative recombination and the resonant dielectronic recombination processes in a unified scheme (S.N. Nahar and A.K. Pradhan, Phys. Rev. A 49, 1816 (1994);H.L. Zhang, S.N. Nahar, and A.K. Pradhan, J.Phys.B, 32,1459 (1999)). Calculations are carried out using the R-matrix method in the close coupling approximation using an identical wavefunction expansion for both processes to ensure self-consistency. The results for photoionization and recombination cross sections may also be compared with state-of-the-art experiments on synchrotron radiation sources for photoionization, and on heavy ion storage rings for recombination. The new experiments display heretofore unprecedented detail in terms of resonances and background cross sections and thereby calibrate the theoretical data precisely. We find a level of agreement between theory and experiment at about 10% for not only the ground state but also the metastable states. The recent experiments therefore verify the estimated accuracy of the vast amount of photoionization data computed under the OP, IP and related works. features. Present work also reports photoionization cross sections including relativistic effects in the Breit-Pauli R-matrix (BPRM) approximation. Detailed features in the calculated cross sections exhibit the missing resonances due to fine structure. Self-consistent datasets for photoionization and recombination have so far been computed for approximately 45 atoms and ions. These are being reported in a continuing series of publications in Astrophysical J. Supplements (e.g. references below). These data will also be available from the electronic database TIPTOPBASE (http://heasarc.gsfc.nasa.gov)
NASA Astrophysics Data System (ADS)
Matsuno, Genki; Kobayashi, Akito
2018-05-01
We evaluate the uniform spin susceptibility in an extended Hubbard model describing α-(BEDT-TTF)2I3. Employing the Fock-type self-energy with the long-range Coulomb interaction and the random phase approximation with the on-site Coulomb interaction, it is clarified that the characteristic energy scales at which ferrimagnetic fluctuation and velocity renormalization emerge are different. This is why these phenomena coexist while the ferrimagnetic fluctuation is disturbed by the velocity renormalization. In addition, it is found that screening effect to the self-energy is irrelevant in the presence of a strong on-site Coulomb interaction U.
Many-Body Effects on Bandgap Shrinkage, Effective Masses, and Alpha Factor
NASA Technical Reports Server (NTRS)
Li, Jian-Zhong; Ning, C. Z.; Woo, Alex C. (Technical Monitor)
2000-01-01
Many-body Coulomb effects influence the operation of quantum-well (QW) laser diode (LD) strongly. In the present work, we study a two-band electron-hole plasma (EHP) within the Hatree-Fock approximation and the single plasmon pole approximation for static screening. Full inclusion of momentum dependence in the many-body effects is considered. An empirical expression for carrier density dependence of the bandgap renormalization (BGR) in an 8 nm GaAs/Al(0.3)G(4.7)As single QW will be given, which demonstrates a non-universal scaling behavior for quasi-two-dimension structures, due to size-dependent efficiency of screening. In addition, effective mass renormalization (EMR) due to momentum-dependent self-energy many-body correction, for both electrons and holes is studied and serves as another manifestation of the many-body effects. Finally, the effects on carrier density dependence of the alpha factor is evaluated to assess the sensitivity of the full inclusion of momentum dependence.
Short- and long-time diffusion and dynamic scaling in suspensions of charged colloidal particles.
Banchio, Adolfo J; Heinen, Marco; Holmqvist, Peter; Nägele, Gerhard
2018-04-07
We report on a comprehensive theory-simulation-experimental study of collective and self-diffusion in concentrated suspensions of charge-stabilized colloidal spheres. In theory and simulation, the spheres are assumed to interact directly by a hard-core plus screened Coulomb effective pair potential. The intermediate scattering function, f c (q, t), is calculated by elaborate accelerated Stokesian dynamics (ASD) simulations for Brownian systems where many-particle hydrodynamic interactions (HIs) are fully accounted for, using a novel extrapolation scheme to a macroscopically large system size valid for all correlation times. The study spans the correlation time range from the colloidal short-time to the long-time regime. Additionally, Brownian Dynamics (BD) simulation and mode-coupling theory (MCT) results of f c (q, t) are generated where HIs are neglected. Using these results, the influence of HIs on collective and self-diffusion and the accuracy of the MCT method are quantified. It is shown that HIs enhance collective and self-diffusion at intermediate and long times. At short times self-diffusion, and for wavenumbers outside the structure factor peak region also collective diffusion, are slowed down by HIs. MCT significantly overestimates the slowing influence of dynamic particle caging. The dynamic scattering functions obtained in the ASD simulations are in overall good agreement with our dynamic light scattering (DLS) results for a concentration series of charged silica spheres in an organic solvent mixture, in the experimental time window and wavenumber range. From the simulation data for the time derivative of the width function associated with f c (q, t), there is indication of long-time exponential decay of f c (q, t), for wavenumbers around the location of the static structure factor principal peak. The experimental scattering functions in the probed time range are consistent with a time-wavenumber factorization scaling behavior of f c (q, t) that was first reported by Segrè and Pusey [Phys. Rev. Lett. 77, 771 (1996)] for suspensions of hard spheres. Our BD simulation and MCT results predict a significant violation of exact factorization scaling which, however, is approximately restored according to the ASD results when HIs are accounted for, consistent with the experimental findings for f c (q, t). Our study of collective diffusion is amended by simulation and theoretical results for the self-intermediate scattering function, f s (q, t), and its non-Gaussian parameter α 2 (t) and for the particle mean squared displacement W(t) and its time derivative. Since self-diffusion properties are not assessed in standard DLS measurements, a method to deduce W(t) approximately from f c (q, t) is theoretically validated.
Fernández, Maria E.; Diamond, Pamela M.; Rakowski, William; Gonzales, Alicia; Tortolero-Luna, Guillermo; Williams, Janet; Morales-Campos, Daisy Y.
2011-01-01
While self-efficacy (SE), a construct from Social Cognitive Theory, has been shown to influence other screening behaviors, few measures currently exist for measuring Pap test SE. This paper describes the development and psychometric testing of such a measure for Mexican-American women. Data from two separate samples of Mexican-American women 50 years or older, obtained as part of a study to develop and evaluate a breast and cervical cancer screening educational program, were used in the current study. Exploratory factor analysis indicated a single factor solution and all item loadings were > .73. Confirmatory analysis confirmed a single factor structure with all standardized loadings greater than .40 as hypothesized. The eight item SE scale demonstrated high internal consistency (Cronbach's alpha = .95). As hypothesized, SE was correlated with knowledge, prior experience, and screening intention. Logistic regression supported the theoretical relationship that women with higher SE were more likely to have had a recent Pap test. Findings showed a significant increase in SE following the intervention, indicating the measure has good sensitivity to change over time. PMID:19258484
Salman, Khlood Faik
2012-01-01
In this exploratory study I investigated the participation status in breast and cervical cancer screening of a group of American immigrant Arab Muslim women (AMW). Perceived knowledge of and barriers to screening participation, relationships among demographic variables, health practice and beliefs, and self-reports of traditionalism and acculturation also are studied. Factors including religious and cultural beliefs, economic concerns, and modesty and embarrassment were considered. To reach the goals of Healthy People 2010 (HP 2010), an effective and meaningful educational initiative to raise awareness about breast and cervical cancer of AMW will require specific interventions consistent with their cultural and religious traditions.
Doubly self-consistent field theory of grafted polymers under simple shear in steady state.
Suo, Tongchuan; Whitmore, Mark D
2014-03-21
We present a generalization of the numerical self-consistent mean-field theory of polymers to the case of grafted polymers under simple shear. The general theoretical framework is presented, and then applied to three different chain models: rods, Gaussian chains, and finitely extensible nonlinear elastic (FENE) chains. The approach is self-consistent at two levels. First, for any flow field, the polymer density profile and effective potential are calculated self-consistently in a manner similar to the usual self-consistent field theory of polymers, except that the calculation is inherently two-dimensional even for a laterally homogeneous system. Second, through the use of a modified Brinkman equation, the flow field and the polymer profile are made self-consistent with respect to each other. For all chain models, we find that reasonable levels of shear cause the chains to tilt, but it has very little effect on the overall thickness of the polymer layer, causing a small decrease for rods, and an increase of no more than a few percent for the Gaussian and FENE chains. Using the FENE model, we also probe the individual bond lengths, bond correlations, and bond angles along the chains, the effects of the shear on them, and the solvent and bonded stress profiles. We find that the approximations needed within the theory for the Brinkman equation affect the bonded stress, but none of the other quantities.
Black, Oliver; Keegel, Tessa; Sim, Malcolm R; Collie, Alexander; Smith, Peter
2018-03-01
Purpose Work absence can result in substantial losses to the economy and workers. As a result, identifying modifiable factors associated with return-to-work (RTW) following an injury or illness is the focus of many empirical investigations. Self-efficacy, the belief about one's ability to undertake behaviours to achieve desired goals, has been identified as an important factor in RTW for injured workers. This paper systematically reviewed the literature on the association between self-efficacy and RTW outcomes for workers with an upper-body musculoskeletal injury or psychological injury. Methods A systematic search was conducted across five databases using two main search concepts- 'self-efficacy' and 'RTW'. After removing duplicates, our search strategy identified 836 studies, which were screened for relevance using titles and abstracts. Results A two stage screening process reduced the study pool to six studies using psychological injury cohorts and three using upper-body musculoskeletal (UB-MSK) cohorts. Eight cohorts from seven prospective cohort studies and one sample from a randomised control trial (RCT) were subjected to a risk of bias assessment. Higher levels of self-efficacy appeared to have a consistent and positive association with RTW across return-to-work status and work absence outcomes, injury type and follow-up periods. Effect ratios ranged from 1.00 to 5.26 indicating a potentially large impact of self-efficacy on RTW outcomes. The relationship between self-efficacy and RTW strengthened as the domain of self-efficacy became more specific to RTW and job behaviours. Studies assessing workers with psychological injuries were of a lower quality compared to those assessing workers with UB-MSK injuries. Conclusions Higher self-efficacy had consistent positive associations with RTW outcomes. Further empirical research should identify the determinants of self-efficacy, and explore the processes by which higher self-efficacy improves RTW outcomes.
Westaway, M S; Wolmarans, L
1992-11-01
One hundred black hospitalized tuberculosis (TB) patients (75 males and 25 females) were interviewed to ascertain levels of depression and self-esteem. The standard of literacy for 65% of the sample was such that they were unable to complete a self-report inventory. Reliability (internal consistency) was good for the 21-item Beck Depression Inventory (BDI: r = 0.79), the 13-item shortened BDI (ABDI: r = 0.76) and the Rosenberg Self-Esteem scale (RSE: r = 0.78). There was a significant positive relationship between the BDI and the ABDI (r = 0.92, P = 0.0001). The recommended ABDI cut-off scores established no depression for 32 patients, mild depression for 22 patients, moderate depression for 38 patients and severe depression for 8 patients. There were significant negative relationships between the BDI and the RSE (r = -0.54, P = 0.0001), and between the ABDI and the RSE (r = -0.56, P = 0.0001). Self-esteem scores dropped in accordance with category of depression, revealing that low self-esteem is a characteristic feature of depression. It was concluded that the ABDI was a reliable, rapid, initial screening device for depression in black persons with low literacy levels.
Approximate solution to the Hopf Phi equation for isotropic homogeneous fluid turbulence
NASA Technical Reports Server (NTRS)
Rosen, G.
1982-01-01
Consistent with the observed t to the -n decay laws for isotropic homogeneous turbulence and the form of the longitudinal correlation function f(r, t) for small r, the Hopf Phi equation is shown to be satisfied approximately by an asymptotic power series in t to the -n. This solution features a self-similar universal equilibrium functional which manifests Kolmogoroff-type scaling.
NASA Astrophysics Data System (ADS)
Lyo, In-Whan
Electronic properties of the epitaxially grown Na(110) film have been studied using angle resolved ultraviolet photoemission spectroscopy with synchrotron radiation as the light source. Na provides an ideal ground to study the fundamental aspects of the electron-electron interactions in metals, because of its simple Fermi surface and small pseudopotential. The absolute band structure of Na(110) using angle resolved photoemission spectroscopy has been mapped out using the extrema searching method. The advantage of this approach is that the usual assumption of the unoccupied state dispersion is not required. We have found that the dispersion of Na(1l0) is very close to the parabolic band with the effective mass 1.21 M_{rm e} at 90 K. Self-consistent calculations of the self-energy for the homogeneous electron gas have been performed using the Green's function technique within the framework of the GW approximation, in the hope of understanding the narrowing mechanism of the bandwidth observed for all the nearly-free-electron (NFE) metals. Good agreements between the experimental data and our calculated self-energy were obtained not only for our data on k-dependency from Na(l10), but also for the total bandwidth corrections for other NFE metals, only if dielectric functions beyond the random phase approximation were used. Our findings emphasize the importance of the screening by long wavelength plasmons. Off-normal spectra of angle resolved photoemission from Na(110) show strong asymmetry of the bulk peak intensity for the wide range of photon energies. Using a simple analysis, we show this asymmetry has an origin in the interference of the surface Umklapp electrons with the normal electrons. We have also performed the detailed experimental studies of the anomalous Fermi level structure observed in the forbidden gap region of Na. This was claimed by A. W. Overhauser as the evidence of the charge density wave in the alkali metal. The possibility of this hypothesis is critically discussed against other explanations.
Analytical model for the radio-frequency sheath
NASA Astrophysics Data System (ADS)
Czarnetzki, Uwe
2013-12-01
A simple analytical model for the planar radio-frequency (rf) sheath in capacitive discharges is developed that is based on the assumptions of a step profile for the electron front, charge exchange collisions with constant cross sections, negligible ionization within the sheath, and negligible ion dynamics. The continuity, momentum conservation, and Poisson equations are combined in a single integro-differential equation for the square of the ion drift velocity, the so called sheath equation. Starting from the kinetic Boltzmann equation, special attention is paid to the derivation and the validity of the approximate fluid equation for momentum balance. The integrals in the sheath equation appear in the screening function which considers the relative contribution of the temporal mean of the electron density to the space charge in the sheath. It is shown that the screening function is quite insensitive to variations of the effective sheath parameters. The two parameters defining the solution are the ratios of the maximum sheath extension to the ion mean free path and the Debye length, respectively. A simple general analytic expression for the screening function is introduced. By means of this expression approximate analytical solutions are obtained for the collisionless as well as the highly collisional case that compare well with the exact numerical solution. A simple transition formula allows application to all degrees of collisionality. In addition, the solutions are used to calculate all static and dynamic quantities of the sheath, e.g., the ion density, fields, and currents. Further, the rf Child-Langmuir laws for the collisionless as well as the collisional case are derived. An essential part of the model is the a priori knowledge of the wave form of the sheath voltage. This wave form is derived on the basis of a cubic charge-voltage relation for individual sheaths, considering both sheaths and the self-consistent self-bias in a discharge with arbitrary symmetry. The externally applied rf voltage is assumed to be sinusoidal, although the model can be extended to arbitrary wave forms, e.g., for dual-frequency discharges. The model calculates explicitly the cubic correction parameter in the charge-voltage relation for the case of highly asymmetric discharges. It is shown that the cubic correction is generally moderate but more pronounced in the collisionless case. The analytical results are compared to experimental data from the literature obtained by laser electric field measurements of the mean and dynamic fields in the capacitive sheath for various gases and pressures. Very good agreement is found throughout.
Analytical model for the radio-frequency sheath.
Czarnetzki, Uwe
2013-12-01
A simple analytical model for the planar radio-frequency (rf) sheath in capacitive discharges is developed that is based on the assumptions of a step profile for the electron front, charge exchange collisions with constant cross sections, negligible ionization within the sheath, and negligible ion dynamics. The continuity, momentum conservation, and Poisson equations are combined in a single integro-differential equation for the square of the ion drift velocity, the so called sheath equation. Starting from the kinetic Boltzmann equation, special attention is paid to the derivation and the validity of the approximate fluid equation for momentum balance. The integrals in the sheath equation appear in the screening function which considers the relative contribution of the temporal mean of the electron density to the space charge in the sheath. It is shown that the screening function is quite insensitive to variations of the effective sheath parameters. The two parameters defining the solution are the ratios of the maximum sheath extension to the ion mean free path and the Debye length, respectively. A simple general analytic expression for the screening function is introduced. By means of this expression approximate analytical solutions are obtained for the collisionless as well as the highly collisional case that compare well with the exact numerical solution. A simple transition formula allows application to all degrees of collisionality. In addition, the solutions are used to calculate all static and dynamic quantities of the sheath, e.g., the ion density, fields, and currents. Further, the rf Child-Langmuir laws for the collisionless as well as the collisional case are derived. An essential part of the model is the a priori knowledge of the wave form of the sheath voltage. This wave form is derived on the basis of a cubic charge-voltage relation for individual sheaths, considering both sheaths and the self-consistent self-bias in a discharge with arbitrary symmetry. The externally applied rf voltage is assumed to be sinusoidal, although the model can be extended to arbitrary wave forms, e.g., for dual-frequency discharges. The model calculates explicitly the cubic correction parameter in the charge-voltage relation for the case of highly asymmetric discharges. It is shown that the cubic correction is generally moderate but more pronounced in the collisionless case. The analytical results are compared to experimental data from the literature obtained by laser electric field measurements of the mean and dynamic fields in the capacitive sheath for various gases and pressures. Very good agreement is found throughout.
NASA Astrophysics Data System (ADS)
Blanchet, Luc; Detweiler, Steven; Le Tiec, Alexandre; Whiting, Bernard F.
2010-03-01
The problem of a compact binary system whose components move on circular orbits is addressed using two different approximation techniques in general relativity. The post-Newtonian (PN) approximation involves an expansion in powers of v/c≪1, and is most appropriate for small orbital velocities v. The perturbative self-force analysis requires an extreme mass ratio m1/m2≪1 for the components of the binary. A particular coordinate-invariant observable is determined as a function of the orbital frequency of the system using these two different approximations. The post-Newtonian calculation is pushed up to the third post-Newtonian (3PN) order. It involves the metric generated by two point particles and evaluated at the location of one of the particles. We regularize the divergent self-field of the particle by means of dimensional regularization. We show that the poles ∝(d-3)-1 appearing in dimensional regularization at the 3PN order cancel out from the final gauge invariant observable. The 3PN analytical result, through first order in the mass ratio, and the numerical self-force calculation are found to agree well. The consistency of this cross cultural comparison confirms the soundness of both approximations in describing compact binary systems. In particular, it provides an independent test of the very different regularization procedures invoked in the two approximation schemes.
Ren, Xinguo; Tkatchenko, Alexandre; Rinke, Patrick; Scheffler, Matthias
2011-04-15
The random-phase approximation (RPA) for the electron correlation energy, combined with the exact-exchange (EX) energy, represents the state-of-the-art exchange-correlation functional within density-functional theory. However, the standard RPA practice--evaluating both the EX and the RPA correlation energies using Kohn-Sham (KS) orbitals from local or semilocal exchange-correlation functionals--leads to a systematic underbinding of molecules and solids. Here we demonstrate that this behavior can be corrected by adding a "single excitation" contribution, so far not included in the standard RPA scheme. A similar improvement can also be achieved by replacing the non-self-consistent EX total energy by the corresponding self-consistent Hartree-Fock total energy, while retaining the RPA correlation energy evaluated using KS orbitals. Both schemes achieve chemical accuracy for a standard benchmark set of noncovalent intermolecular interactions.
NASA Astrophysics Data System (ADS)
Li, Yan; Harbola, Manoj K.; Krieger, J. B.; Sahni, Viraht
1989-11-01
The exchange-correlation potential of the Kohn-Sham density-functional theory has recently been interpreted as the work required to move an electron against the electric field of its Fermi-Coulomb hole charge distribution. In this paper we present self-consistent results for ground-state total energies and highest occupied eigenvalues of closed subshell atoms as obtained by this formalism in the exchange-only approximation. The total energies, which are an upper bound, lie within 50 ppm of Hartree-Fock theory for atoms heavier than Be. The highest occupied eigenvalues, as a consequence of this interpretation, approximate well the experimental ionization potentials. In addition, the self-consistently calculated exchange potentials are very close to those of Talman and co-workers [J. D. Talman and W. F. Shadwick, Phys. Rev. A 14, 36 (1976); K. Aashamar, T. M. Luke, and J. D. Talman, At. Data Nucl. Data Tables 22, 443 (1978)].
Ground state properties of 3d metals from self-consistent GW approach
Kutepov, Andrey L.
2017-10-06
The self consistent GW approach (scGW) has been applied to calculate the ground state properties (equilibrium Wigner–Seitz radius S WZ and bulk modulus B) of 3d transition metals Sc, Ti, V, Fe, Co, Ni, and Cu. The approach systematically underestimates S WZ with average relative deviation from the experimental data of about 1% and it overestimates the calculated bulk modulus with relative error of about 25%. We show that scGW is superior in accuracy as compared to the local density approximation but it is less accurate than the generalized gradient approach for the materials studied. If compared to the randommore » phase approximation, scGW is slightly less accurate, but its error for 3d metals looks more systematic. Lastly, the systematic nature of the deviation from the experimental data suggests that the next order of the perturbation theory should allow one to reduce the error.« less
Ground state properties of 3d metals from self-consistent GW approach
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kutepov, Andrey L.
The self consistent GW approach (scGW) has been applied to calculate the ground state properties (equilibrium Wigner–Seitz radius S WZ and bulk modulus B) of 3d transition metals Sc, Ti, V, Fe, Co, Ni, and Cu. The approach systematically underestimates S WZ with average relative deviation from the experimental data of about 1% and it overestimates the calculated bulk modulus with relative error of about 25%. We show that scGW is superior in accuracy as compared to the local density approximation but it is less accurate than the generalized gradient approach for the materials studied. If compared to the randommore » phase approximation, scGW is slightly less accurate, but its error for 3d metals looks more systematic. Lastly, the systematic nature of the deviation from the experimental data suggests that the next order of the perturbation theory should allow one to reduce the error.« less
Quality assurance in pathology in colorectal cancer screening and diagnosis—European recommendations
Quirke, Phil; Risio, Mauro; Lambert, René; von Karsa, Lawrence
2010-01-01
In Europe, colorectal cancer is the most common newly diagnosed cancer and the second most common cause of cancer deaths, accounting for approximately 436,000 incident cases and 212,000 deaths in 2008. The potential of high-quality screening to improve control of the disease has been recognized by the Council of the European Union who issued a recommendation on cancer screening in 2003. Multidisciplinary, evidence-based European Guidelines for quality assurance in colorectal cancer screening and diagnosis have recently been developed by experts in a pan-European project coordinated by the International Agency for Research on Cancer. The full guideline document consists of ten chapters and an extensive evidence base. The content of the chapter dealing with pathology in colorectal cancer screening and diagnosis is presented here in order to promote international discussion and collaboration leading to improvements in colorectal cancer screening and diagnosis by making the principles and standards recommended in the new EU Guidelines known to a wider scientific community. PMID:21061133
McLachlan, E; Anderson, S; Hawkes, D; Saville, M; Arabena, K
2018-02-01
To examine factors that enhance under-screened and never-screened women's completion of the self-collection alternative pathway of the Renewed National Cervical Screening Program (ncsp) in Victoria, Australia. With the Australian ncsp changing, starting on 1 December 2017, the Medical Services Advisory Committee (msac) recommended implementing human papillomavirus (hpv) testing using a self-collected sample for under-screened and never-screened populations. In response, a multi-agency group implemented an hpv self-collection pilot project to trial self-collection screening pathways for eligible women. Quantitative data were collected on participation rates and compliance rates with follow-up procedures across three primary health care settings. Forty women who self-collected were interviewed in a semi-structured format, and seven agency staff completed in-depth interviews. Qualitative data were used to identify and understand clinical and personal enablers that assisted women to complete self-collection cervical screening pathways successfully. Eighty-five per cent (10 women) of participants who tested positive for hpv successfully received their results and completed follow-up procedures as required. Two remaining participants also received hpv-positive results. However, agencies were unable to engage them in follow-up services and procedures. The overall participation rate in screening (self-collection or Pap test) was 85.7% (84 women), with 79 women self-collecting. Qualitative data indicated that clear explanations on self-collection, development of trusting, empathetic relationships with health professionals, and recognition of participants' past experiences were critical to the successful completion of the self-collection pathway. When asked about possible inhibitors to screening and to following up on results and appointments, women cited poor physical and mental health, as well as financial and other structural barriers. A well-implemented process, led by trusted, knowledgeable, and engaged health care professionals who can provide appropriate support and information, can assist under-screened and never-screened women to complete the hpv self-collection pathway successfully.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kutzler, F.W.; Painter, G.S.
1992-02-15
A fully self-consistent series of nonlocal (gradient) density-functional calculations has been carried out using the augmented-Gaussian-orbital method to determine the magnitude of gradient corrections to the potential-energy curves of the first-row diatomics, Li{sub 2} through F{sub 2}. Both the Langreth-Mehl-Hu and the Perdew-Wang gradient-density functionals were used in calculations of the binding energy, bond length, and vibrational frequency for each dimer. Comparison with results obtained in the local-spin-density approximation (LSDA) using the Vosko-Wilk-Nusair functional, and with experiment, reveals that bond lengths and vibrational frequencies are rather insensitive to details of the gradient functionals, including self-consistency effects, but the gradient correctionsmore » reduce the overbinding commonly observed in the LSDA calculations of first-row diatomics (with the exception of Li{sub 2}, the gradient-functional binding-energy error is only 50--12 % of the LSDA error). The improved binding energies result from a large differential energy lowering, which occurs in open-shell atoms relative to the diatomics. The stabilization of the atom arises from the use of nonspherical charge and spin densities in the gradient-functional calculations. This stabilization is negligibly small in LSDA calculations performed with nonspherical densities.« less
Longitudinal Consistency in Self-Reported Age of First Vaginal Intercourse Among Young Adults
Goldberg, Shoshana K.; Haydon, Abigail A.; Herring, Amy H.; Halpern, Carolyn T.
2014-01-01
We examined consistency in self-reports of age at first vaginal sex among 9,399 male and female respondents who participated in Waves III and IV (separated by approximately 7 years) of the National Longitudinal Study of Adolescent Health (Add Health). Respondents were coded as consistent if they reported an age at first vaginal intercourse at Wave IV that was within 1 year of the age they reported at Wave III. Sociodemographic, behavioral, and cognitive predictors of consistency were examined using bivariate and multivariate logistic regression. Overall, 85.43% of respondents were able to provide consistent reports. Among both males and females, consistency was associated with age, years since first vaginal intercourse, race/ethnicity, and lifetime number of other-sex partners in final multivariate models. Respondents who were older and had more recently had their first sexual experience were more likely to be consistent. For females only, those who reported a history of non-parental, physically forced sex were less likely to be consistent. Most young adults consistently report age at first vaginal intercourse, supporting the credibility of retrospective self-reports about salient sexual events such as timing of first vaginal intercourse. PMID:23237101
Validation of a New Measure of the Concept of Good Death among Taiwanese Children
ERIC Educational Resources Information Center
Yang, Shu Ching; Lai, Sih-yi
2012-01-01
The purpose of this study was to develop and validate an instrument to measure dimensions of the concept of a good death held by Taiwanese children. The sample consisted of 1,698 Taiwanese children, approximately 12-14 years of age. Participants completed the self-administered Good Death Concept Scale (GDCS), which consists of 30 statements…
NASA Astrophysics Data System (ADS)
Zhou, Yuzhi; Wang, Han; Liu, Yu; Gao, Xingyu; Song, Haifeng
2018-03-01
The Kerker preconditioner, based on the dielectric function of homogeneous electron gas, is designed to accelerate the self-consistent field (SCF) iteration in the density functional theory calculations. However, a question still remains regarding its applicability to the inhomogeneous systems. We develop a modified Kerker preconditioning scheme which captures the long-range screening behavior of inhomogeneous systems and thus improves the SCF convergence. The effectiveness and efficiency is shown by the tests on long-z slabs of metals, insulators, and metal-insulator contacts. For situations without a priori knowledge of the system, we design the a posteriori indicator to monitor if the preconditioner has suppressed charge sloshing during the iterations. Based on the a posteriori indicator, we demonstrate two schemes of the self-adaptive configuration for the SCF iteration.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neradilek, Moni B.; Polissar, Nayak L.; Einstein, Daniel R.
2012-04-24
We examine a previously published branch-based approach to modeling airway diameters that is predicated on the assumption of self-consistency across all levels of the tree. We mathematically formulate this assumption, propose a method to test it and develop a more general model to be used when the assumption is violated. We discuss the effect of measurement error on the estimated models and propose methods that account for it. The methods are illustrated on data from MRI and CT images of silicone casts of two rats, two normal monkeys and one ozone-exposed monkey. Our results showed substantial departures from self-consistency inmore » all five subjects. When departures from selfconsistency exist we do not recommend using the self-consistency model, even as an approximation, as we have shown that it may likely lead to an incorrect representation of the diameter geometry. Measurement error has an important impact on the estimated morphometry models and needs to be accounted for in the analysis.« less
Self-consistent-field perturbation theory for the Schröautdinger equation
NASA Astrophysics Data System (ADS)
Goodson, David Z.
1997-06-01
A method is developed for using large-order perturbation theory to solve the systems of coupled differential equations that result from the variational solution of the Schröautdinger equation with wave functions of product form. This is a noniterative, computationally efficient way to solve self-consistent-field (SCF) equations. Possible applications include electronic structure calculations using products of functions of collective coordinates that include electron correlation, vibrational SCF calculations for coupled anharmonic oscillators with selective coupling of normal modes, and ab initio calculations of molecular vibration spectra without the Born-Oppenheimer approximation.
Self-consistent chaos in a mean-field Hamiltonian model of fluids and plasmas
NASA Astrophysics Data System (ADS)
del-Castillo-Negrete, D.; Firpo, Marie-Christine
2002-11-01
We present a mean-field Hamiltonian model that describes the collective dynamics of marginally stable fluids and plasmas. In plasmas, the model describes the self-consistent evolution of electron holes and clumps in phase space. In fluids, the model describes the dynamics of vortices with negative and positive circulation in shear flows. The mean-field nature of the system makes it a tractable model to study the dynamics of large degrees-of-freedom, coupled Hamiltonian systems. Here we focus in the role of self-consistent chaos in the formation and destruction of phase space coherent structures. Numerical simulations in the finite N and in the Narrow kinetic limit (where N is the number of particles) show the existence of coherent, rotating dipole states. We approximate the dipole as two macroparticles, and show that the N = 2 limit has a family of rotating integrable solutions described by a one degree-of-freedom nontwist Hamiltonian. The coherence of the dipole is explained in terms of a parametric resonance between the rotation frequency of the macroparticles and the oscillation frequency of the self-consistent mean field. For a class of initial conditions, the mean field exhibits a self-consistent, elliptic-hyperbolic bifurcation that leads to the destruction of the dipole and violent mixing of the phase space.
Conners-Burrow, Nicola; McKelvey, Lorraine; Kyzer, Angela; Swindle, Taren; Cheerla, Rajalakshmi; Kraleti, Shashank
2013-01-01
We explore the associations between exposure to conflict and crime in the home and community, and child anxiety and self-control problems among 60 children whose mothers were in treatment for substance abuse problems. Experiences with violence and crime were widespread, with many children exposed to multiple incidents. Approximately one-third (35.5%) of children exhibited clinically elevated anxiety. Controlling for other potential predictors, both children's exposure to violence and the number of years the mother had been using substances predicted higher anxiety in children, while only exposure to violence predicted problems in self-control. Results highlight the importance of screening for violence exposure. Copyright © 2013 Elsevier Inc. All rights reserved.
Telescopic multi-resolution augmented reality
NASA Astrophysics Data System (ADS)
Jenkins, Jeffrey; Frenchi, Christopher; Szu, Harold
2014-05-01
To ensure a self-consistent scaling approximation, the underlying microscopic fluctuation components can naturally influence macroscopic means, which may give rise to emergent observable phenomena. In this paper, we describe a consistent macroscopic (cm-scale), mesoscopic (micron-scale), and microscopic (nano-scale) approach to introduce Telescopic Multi-Resolution (TMR) into current Augmented Reality (AR) visualization technology. We propose to couple TMR-AR by introducing an energy-matter interaction engine framework that is based on known Physics, Biology, Chemistry principles. An immediate payoff of TMR-AR is a self-consistent approximation of the interaction between microscopic observables and their direct effect on the macroscopic system that is driven by real-world measurements. Such an interdisciplinary approach enables us to achieve more than multiple scale, telescopic visualization of real and virtual information but also conducting thought experiments through AR. As a result of the consistency, this framework allows us to explore a large dimensionality parameter space of measured and unmeasured regions. Towards this direction, we explore how to build learnable libraries of biological, physical, and chemical mechanisms. Fusing analytical sensors with TMR-AR libraries provides a robust framework to optimize testing and evaluation through data-driven or virtual synthetic simulations. Visualizing mechanisms of interactions requires identification of observable image features that can indicate the presence of information in multiple spatial and temporal scales of analog data. The AR methodology was originally developed to enhance pilot-training as well as `make believe' entertainment industries in a user-friendly digital environment We believe TMR-AR can someday help us conduct thought experiments scientifically, to be pedagogically visualized in a zoom-in-and-out, consistent, multi-scale approximations.
Transitioning NWChem to the Next Generation of Manycore Machines
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bylaska, Eric J.; Apra, E; Kowalski, Karol
The NorthWest chemistry (NWChem) modeling software is a popular molecular chemistry simulation software that was designed from the start to work on massively parallel processing supercomputers [1-3]. It contains an umbrella of modules that today includes self-consistent eld (SCF), second order Møller-Plesset perturbation theory (MP2), coupled cluster (CC), multiconguration self-consistent eld (MCSCF), selected conguration interaction (CI), tensor contraction engine (TCE) many body methods, density functional theory (DFT), time-dependent density functional theory (TDDFT), real-time time-dependent density functional theory, pseudopotential plane-wave density functional theory (PSPW), band structure (BAND), ab initio molecular dynamics (AIMD), Car-Parrinello molecular dynamics (MD), classical MD, hybrid quantum mechanicsmore » molecular mechanics (QM/MM), hybrid ab initio molecular dynamics molecular mechanics (AIMD/MM), gauge independent atomic orbital nuclear magnetic resonance (GIAO NMR), conductor like screening solvation model (COSMO), conductor-like screening solvation model based on density (COSMO-SMD), and reference interaction site model (RISM) solvation models, free energy simulations, reaction path optimization, parallel in time, among other capabilities [4]. Moreover, new capabilities continue to be added with each new release.« less
Russell, Kathleen M; Champion, Victoria L; Monahan, Patrick O; Millon-Underwood, Sandra; Zhao, Qianqian; Spacey, Nicole; Rush, Nathan L; Paskett, Electra D
2010-01-01
Low-income African American women face numerous barriers to mammography screening. We tested the efficacy of a combined interactive computer program and lay health advisor intervention to increase mammography screening. In this randomized, single blind study, participants were 181 African American female health center patients of ages 41 to 75 years, at < or =250% of poverty level, with no breast cancer history, and with no screening mammogram in the past 15 months. They were assigned to either (a) a low-dose comparison group consisting of a culturally appropriate mammography screening pamphlet or (b) interactive, tailored computer instruction at baseline and four monthly lay health advisor counseling sessions. Self-reported screening data were collected at baseline and 6 months and verified by medical record. For intent-to-treat analysis of primary outcome (medical record-verified mammography screening, available on all but two participants), the intervention group had increased screening to 51% (45 of 89) compared with 18% (16 of 90) for the comparison group at 6 months. When adjusted for employment status, disability, first-degree relatives with breast cancer, health insurance, and previous breast biopsies, the intervention group was three times more likely (adjusted relative risk, 2.7; 95% confidence interval, 1.8-3.7; P < 0.0001) to get screened than the low-dose comparison group. Similar results were found for self-reported mammography stage of screening adoption. The combined intervention was efficacious in improving mammography screening in low-income African American women, with an unadjusted effect size (relative risk, 2.84) significantly higher (P < 0.05) than that in previous studies of each intervention alone.
How important is self-consistency for the dDsC density dependent dispersion correction?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brémond, Éric; Corminboeuf, Clémence, E-mail: clemence.corminboeuf@epfl.ch; Golubev, Nikolay
2014-05-14
The treatment of dispersion interactions is ubiquitous but computationally demanding for seamless ab initio approaches. A highly popular and simple remedy consists in correcting for the missing interactions a posteriori by adding an attractive energy term summed over all atom pairs to standard density functional approximations. These corrections were originally based on atom pairwise parameters and, hence, had a strong touch of empiricism. To overcome such limitations, we recently proposed a robust system-dependent dispersion correction, dDsC, that is computed from the electron density and that provides a balanced description of both weak inter- and intramolecular interactions. From the theoretical pointmore » of view and for the sake of increasing reliability, we here verify if the self-consistent implementation of dDsC impacts ground-state properties such as interaction energies, electron density, dipole moments, geometries, and harmonic frequencies. In addition, we investigate the suitability of the a posteriori scheme for molecular dynamics simulations, for which the analysis of the energy conservation constitutes a challenging tests. Our study demonstrates that the post-SCF approach in an excellent approximation.« less
NASA Astrophysics Data System (ADS)
Gunko, Yuri F.; Gunko, Natalia A.
2018-05-01
In this paper we consider the problem of determining the structure of the electric field near the surface of a flat insulated body under conditions of a deep vacuum. It is assumed that the emitted particles are electrons leaving the body surface under the influence of ionizing radiation whose velocities distribution near the surface is isotropic. It is estimated the thickness of the screening layer under conditions of stationary emission from a flat surface. The solutio of the problem of determining a stationary self-consistent electric field near the surface is found in a simple analytical form. The thickness of the screening layer is calculated from this formula.
McQueen, Amy; Swank, Paul R; Vernon, Sally W
2014-11-01
To reduce negative psychological affect from information or behavior that is inconsistent with one's positive self-concept, individuals use a variety of defensive strategies. It is unknown whether correlates differ across defenses. We examined correlates of four levels of defensive information processing about colorectal cancer screening. Cross-sectional surveys were completed by a convenience sample of 287 adults aged 50-75 years. Defenses measures were more consistently associated with individual differences (especially avoidant coping styles); however, situational variables involving health-care providers also were important. Future research should examine changes in defenses after risk communication and their relative impact on colorectal cancer screening. © The Author(s) 2013.
NASA Astrophysics Data System (ADS)
Phillips, Jordan J.; Zgid, Dominika
2014-06-01
We report an implementation of self-consistent Green's function many-body theory within a second-order approximation (GF2) for application with molecular systems. This is done by iterative solution of the Dyson equation expressed in matrix form in an atomic orbital basis, where the Green's function and self-energy are built on the imaginary frequency and imaginary time domain, respectively, and fast Fourier transform is used to efficiently transform these quantities as needed. We apply this method to several archetypical examples of strong correlation, such as a H32 finite lattice that displays a highly multireference electronic ground state even at equilibrium lattice spacing. In all cases, GF2 gives a physically meaningful description of the metal to insulator transition in these systems, without resorting to spin-symmetry breaking. Our results show that self-consistent Green's function many-body theory offers a viable route to describing strong correlations while remaining within a computationally tractable single-particle formalism.
Self-consistent theory of atomic Fermi gases with a Feshbach resonance at the superfluid transition
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liu Xiaji; Hu Hui
2005-12-15
A self-consistent theory is derived to describe the BCS-Bose-Einstein-condensate crossover for a strongly interacting Fermi gas with a Feshbach resonance. In the theory the fluctuation of the dressed molecules, consisting of both preformed Cooper pairs and 'bare' Feshbach molecules, has been included within a self-consistent T-matrix approximation, beyond the Nozieres and Schmitt-Rink strategy considered by Ohashi and Griffin. The resulting self-consistent equations are solved numerically to investigate the normal-state properties of the crossover at various resonance widths. It is found that the superfluid transition temperature T{sub c} increases monotonically at all widths as the effective interaction between atoms becomes moremore » attractive. Furthermore, a residue factor Z{sub m} of the molecule's Green function and a complex effective mass have been determined to characterize the fraction and lifetime of Feshbach molecules at T{sub c}. Our many-body calculations of Z{sub m} agree qualitatively well with recent measurments of the gas of {sup 6}Li atoms near the broad resonance at 834 G. The crossover from narrow to broad resonances has also been studied.« less
Doubly self-consistent field theory of grafted polymers under simple shear in steady state
DOE Office of Scientific and Technical Information (OSTI.GOV)
Suo, Tongchuan; Whitmore, Mark D., E-mail: mark-whitmore@umanitoba.ca
2014-03-21
We present a generalization of the numerical self-consistent mean-field theory of polymers to the case of grafted polymers under simple shear. The general theoretical framework is presented, and then applied to three different chain models: rods, Gaussian chains, and finitely extensible nonlinear elastic (FENE) chains. The approach is self-consistent at two levels. First, for any flow field, the polymer density profile and effective potential are calculated self-consistently in a manner similar to the usual self-consistent field theory of polymers, except that the calculation is inherently two-dimensional even for a laterally homogeneous system. Second, through the use of a modified Brinkmanmore » equation, the flow field and the polymer profile are made self-consistent with respect to each other. For all chain models, we find that reasonable levels of shear cause the chains to tilt, but it has very little effect on the overall thickness of the polymer layer, causing a small decrease for rods, and an increase of no more than a few percent for the Gaussian and FENE chains. Using the FENE model, we also probe the individual bond lengths, bond correlations, and bond angles along the chains, the effects of the shear on them, and the solvent and bonded stress profiles. We find that the approximations needed within the theory for the Brinkman equation affect the bonded stress, but none of the other quantities.« less
McLachlan, E.; Anderson, S.; Hawkes, D.; Saville, M.; Arabena, K.
2018-01-01
Objectives To examine factors that enhance under-screened and never-screened women’s completion of the self-collection alternative pathway of the Renewed National Cervical Screening Program (ncsp) in Victoria, Australia. Background With the Australian ncsp changing, starting on 1 December 2017, the Medical Services Advisory Committee (msac) recommended implementing human papillomavirus (hpv) testing using a self-collected sample for under-screened and never-screened populations. In response, a multi-agency group implemented an hpv self-collection pilot project to trial self-collection screening pathways for eligible women. Methods Quantitative data were collected on participation rates and compliance rates with follow-up procedures across three primary health care settings. Forty women who self-collected were interviewed in a semi-structured format, and seven agency staff completed in-depth interviews. Qualitative data were used to identify and understand clinical and personal enablers that assisted women to complete self-collection cervical screening pathways successfully. Results Eighty-five per cent (10 women) of participants who tested positive for hpv successfully received their results and completed follow-up procedures as required. Two remaining participants also received hpv-positive results. However, agencies were unable to engage them in follow-up services and procedures. The overall participation rate in screening (self-collection or Pap test) was 85.7% (84 women), with 79 women self-collecting. Qualitative data indicated that clear explanations on self-collection, development of trusting, empathetic relationships with health professionals, and recognition of participants’ past experiences were critical to the successful completion of the self-collection pathway. When asked about possible inhibitors to screening and to following up on results and appointments, women cited poor physical and mental health, as well as financial and other structural barriers. Conclusion A well-implemented process, led by trusted, knowledgeable, and engaged health care professionals who can provide appropriate support and information, can assist under-screened and never-screened women to complete the hpv self-collection pathway successfully. PMID:29507491
Knapp, Jane F; Dowd, M Denise; Kennedy, Christopher S; Stallbaumer-Rouyer, Jennifer; Henderson, Deborah P
2006-01-01
We sought to describe the assessment of course participant changes in attitudes, self-efficacy, and behaviors after completion of the Its Time to Ask training curriculum for screening for intimate partner violence (IPV) in a pediatric emergency department (PED). A 22-item Likert scale questionnaire was administered at baseline (before training), after training, and at 6-month follow-up to PED employee participants in a 2-hour IPV education program. Mean participant responses were compared between baseline/posttraining and baseline/6-month follow-up. Participants also completed a course-satisfaction survey. A total of 79 PED staff completed the baseline questionnaire before the training. Eighty-seven participants completed the posttraining questionnaire, and 48 completed the 6-month follow-up questionnaire. Participants had consistent, positive changes in attitudes after training that persisted at the 6-month follow-up for 5 items on the questionnaire. Attitudes that did not change showed baseline means already in disagreement with questionnaire statements. Participants reported significant, positive changes for all 7 self-efficacy statements at 1 or both of the posttraining evaluations. The only changes in behavior were observed at 6 months. The majority of participants were satisfied with the training and would recommend it to colleagues. Significant, self-reported changes in attitudes, self-efficacy, and behaviors/clinical practice regarding screening for IPV in a PED can be achieved through participation in a brief training curriculum.
Kleinman, L; Leidy, N K; Crawley, J; Bonomi, A; Schoenfeld, P
2001-02-01
Although most health-related quality of life questionnaires are self-administered by means of paper and pencil, new technologies for automated computer administration are becoming more readily available. Novel methods of instrument administration must be assessed for score equivalence in addition to consistency in reliability and validity. The present study compared the psychometric characteristics (score equivalence and structure, internal consistency, and reproducibility reliability and construct validity) of the Quality of Life in Reflux And Dyspepsia (QOLRAD) questionnaire when self-administered by means of paper and pencil versus touch-screen computer. The influence of age, education, and prior experience with computers on score equivalence was also examined. This crossover trial randomized 134 patients with gastroesophageal reflux disease to 1 of 2 groups: paper-and-pencil questionnaire administration followed by computer administration or computer administration followed by use of paper and pencil. To minimize learning effects and respondent fatigue, administrations were scheduled 3 days apart. A random sample of 32 patients participated in a 1-week reproducibility evaluation of the computer-administered QOLRAD. QOLRAD scores were equivalent across the 2 methods of administration regardless of subject age, education, and prior computer use. Internal consistency levels were very high (alpha = 0.93-0.99). Interscale correlations were strong and generally consistent across methods (r = 0.7-0.87). Correlations between the QOLRAD and Short Form 36 (SF-36) were high, with no significant differences by method. Test-retest reliability of the computer-administered QOLRAD was also very high (ICC = 0.93-0.96). Results of the present study suggest that the QOLRAD is reliable and valid when self-administered by means of computer touch-screen or paper and pencil.
Transport across nanogaps using self-consistent boundary conditions
NASA Astrophysics Data System (ADS)
Biswas, D.; Kumar, R.
2012-06-01
Charge particle transport across nanogaps is studied theoretically within the Schrodinger-Poisson mean field framework. The determination of self-consistent boundary conditions across the gap forms the central theme in order to allow for realistic interface potentials (such as metal-vacuum) which are smooth at the boundary and do not abruptly assume a constant value at the interface. It is shown that a semiclassical expansion of the transmitted wavefunction leads to approximate but self consistent boundary conditions without assuming any specific form of the potential beyond the gap. Neglecting the exchange and correlation potentials, the quantum Child-Langmuir law is investigated. It is shown that at zero injection energy, the quantum limiting current density (Jc) is found to obey the local scaling law Jc ~ Vgα/D5-2α with the gap separation D and voltage Vg. The exponent α > 1.1 with α → 3/2 in the classical regime of small de Broglie wavelengths.
Yan, Xin-Zhong
2011-07-01
The discrete Fourier transform is approximated by summing over part of the terms with corresponding weights. The approximation reduces significantly the requirement for computer memory storage and enhances the numerical computation efficiency with several orders without losing accuracy. As an example, we apply the algorithm to study the three-dimensional interacting electron gas under the renormalized-ring-diagram approximation where the Green's function needs to be self-consistently solved. We present the results for the chemical potential, compressibility, free energy, entropy, and specific heat of the system. The ground-state energy obtained by the present calculation is compared with the existing results of Monte Carlo simulation and random-phase approximation.
Paskett, Electra D.; McLaughlin, John M.; Lehman, Amy M.; Katz, Mira L.; Tatum, Cathy M.; Oliveri, Jill M.
2011-01-01
Background Cervical cancer is a significant health disparity among women in Ohio Appalachia. The goal of this study was to evaluate the efficacy of a lay health advisor (LHA) intervention for improving Pap testing rates, to reduce cervical cancer, among women in need of screening. Methods Women from 14 Ohio Appalachian clinics in need of a Pap test were randomized to receive either usual care or an LHA intervention over a ten-month period. The intervention consisted of two in-person visits with an LHA, two phone calls, and four post cards. Both self-report and medical record review (MRR) data (primary outcome) were analyzed. Results Of the 286 women, 145 and 141 were randomized to intervention and usual care arms, respectively. According to MRR, more women in the LHA arm had a Pap test by the end of the study compared to those randomized to usual care (51.1% vs. 42.0%; OR=1.44, 95%CI: 0.89, 2.33; p=0.135). Results of self-report were more pronounced (71.3% vs. 54.2%; OR=2.10, 95%CI: 1.22, 3.61; p=0.008). Conclusions An LHA intervention showed some improvement in the receipt of Pap tests among Ohio Appalachian women in need of screening. While biases inherent in using self-reports of screening are well known, this study also identified biases in using MRR data in clinics located in underserved areas. Impact LHA interventions show promise for improving screening behaviors among non-adherent women from underserved populations. PMID:21430302
Hung, Linda; da Jornada, Felipe H.; Souto-Casares, Jaime; ...
2016-08-15
Here, we present first-principles calculations on the vertical ionization potentials (IPs), electron affinities (EAs), and singlet excitation energies on an aromatic-molecule test set (benzene, thiophene, 1,2,5-thiadiazole, naphthalene, benzothiazole, and tetrathiafulvalene) within the GW and Bethe-Salpeter equation (BSE) formalisms. Our computational framework, which employs a real-space basis for ground-state and a transition-space basis for excited-state calculations, is well suited for high-accuracy calculations on molecules, as we show by comparing against G0W0 calculations within a plane-wave-basis formalism. We then generalize our framework to test variants of the GW approximation that include a local density approximation (LDA)–derived vertex function (Γ LDA ) andmore » quasiparticle-self-consistent (QS) iterations. We find that Γ LDA and quasiparticle self-consistency shift IPs and EAs by roughly the same magnitude, but with opposite sign for IPs and the same sign for EAs. G0W0 and QS GWΓ LDA are more accurate for IPs, while G 0W 0Γ LDA and QS GW are best for EAs. For optical excitations, we find that perturbative GW-BSE underestimates the singlet excitation energy, while self-consistent GW-BSE results in good agreement with previous best-estimate values for both valence and Rydberg excitations. Finally, our work suggests that a hybrid approach, in which G0W0 energies are used for occupied orbitals and G0W0Γ LDA for unoccupied orbitals, also yields optical excitation energies in good agreement with experiment but at a smaller computational cost.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hung, Linda; da Jornada, Felipe H.; Souto-Casares, Jaime
Here, we present first-principles calculations on the vertical ionization potentials (IPs), electron affinities (EAs), and singlet excitation energies on an aromatic-molecule test set (benzene, thiophene, 1,2,5-thiadiazole, naphthalene, benzothiazole, and tetrathiafulvalene) within the GW and Bethe-Salpeter equation (BSE) formalisms. Our computational framework, which employs a real-space basis for ground-state and a transition-space basis for excited-state calculations, is well suited for high-accuracy calculations on molecules, as we show by comparing against G0W0 calculations within a plane-wave-basis formalism. We then generalize our framework to test variants of the GW approximation that include a local density approximation (LDA)–derived vertex function (Γ LDA ) andmore » quasiparticle-self-consistent (QS) iterations. We find that Γ LDA and quasiparticle self-consistency shift IPs and EAs by roughly the same magnitude, but with opposite sign for IPs and the same sign for EAs. G0W0 and QS GWΓ LDA are more accurate for IPs, while G 0W 0Γ LDA and QS GW are best for EAs. For optical excitations, we find that perturbative GW-BSE underestimates the singlet excitation energy, while self-consistent GW-BSE results in good agreement with previous best-estimate values for both valence and Rydberg excitations. Finally, our work suggests that a hybrid approach, in which G0W0 energies are used for occupied orbitals and G0W0Γ LDA for unoccupied orbitals, also yields optical excitation energies in good agreement with experiment but at a smaller computational cost.« less
Huang, Yun-Hsin; Wu, Chih-Hsun; Chen, Hsiu-Jung; Cheng, Yih-Ru; Hung, Fu-Chien; Leung, Kai-Kuan; Lue, Bee-Horng; Chen, Ching-Yu; Chiu, Tai-Yuan; Wu, Yin-Chang
2018-01-16
Severe negative emotional reactions to chronic illness are maladaptive to patients and they need to be addressed in a primary care setting. The psychometric properties of a quick screening tool-the Negative Emotions due to Chronic Illness Screening Test (NECIS)-for general emotional problems among patients with chronic illness being treated in a primary care setting was investigated. Three studies including 375 of patients with chronic illness were used to assess and analyze internal consistency, test-retest reliability, criterion-related validity, a cut-off point for distinguishing maladaptive emotions and clinical application validity of NECIS. Self-report questionnaires were used. Internal consistency (Cronbach's α) ranged from 0.78 to 0.82, and the test-retest reliability was 0.71 (P < 0.001). Criterion-related validity was 0.51 (P < 0.001). Based on the 'severe maladaptation' and 'moderate maladaptation' groups defined by using the 'Worsening due to Chronic Illness' index as the analysis reference, the receiver-operating characteristic curve analysis revealed an area under the curve of 0.81 and 0.82 (ps < 0.001), and a cut-off point of 19/20 was the most satisfactory for distinguishing those with overly negative emotions, with a sensitivity and specificity of 83.3 and 69.0%, and 68.5 and 83.0%, respectively. The clinical application validity analysis revealed that low NECIS group showed significantly better adaptation to chronic illness on the scales of subjective health, general satisfaction with life, self-efficacy of self-care for disease, illness perception and stressors in everyday life. The NECIS has satisfactory psychometric properties for use in the primary care setting. © The Author 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
A Self-Regulation Theory–Based Asthma Management Mobile App for Adolescents: A Usability Assessment
2017-01-01
Background Self-regulation theory suggests people learn to influence their own behavior through self-monitoring, goal-setting, feedback, self-reward, and self-instruction, all of which smartphones are now capable of facilitating. Several mobile apps exist to manage asthma; however, little evidence exists about whether these apps employ user-centered design processes that adhere to government usability guidelines for mobile apps. Objective Building upon a previous study that documented adolescent preferences for an asthma self-management app, we employed a user-centered approach to assess the usability of a high-fidelity wireframe for an asthma self-management app intended for use by adolescents with persistent asthma. Methods Individual interviews were conducted with adolescents (ages 11-18 years) with persistent asthma who owned a smartphone (N=8). Adolescents were asked to evaluate a PDF app wireframe consisting of 76 screen shots displaying app features, including log in and home screen, profile setup, settings and info, self-management features, and graphical displays for charting asthma control and medication. Preferences, comments, and suggestions for each set of screen shots were assessed using the audio-recorded interviews. Two coders reached consensus on adolescent evaluations of the following aspects of app features: (1) usability, (2) behavioral intentions to use, (3) confusing aspects, and (4) suggestions for improvement. Results The app wireframe was generally well received, and several suggestions for improvement were recorded. Suggestions included increased customization of charts and notifications, reminders, and alerts. Participants preferred longitudinal data about asthma control and medication use to be displayed using line graphs. All participants reported that they would find an asthma management app like the one depicted in the wireframe useful for managing their asthma. Conclusions Early stage usability tests guided by government usability guidelines (usability.gov) revealed areas for improvement for an asthma self-management app for adolescents. Addressing these areas will be critical to developing an engaging and effective asthma self-management app that is capable of improving adolescent asthma outcomes. PMID:28148471
ERIC Educational Resources Information Center
Park, Bitnara Jasmine; Alonzo, Julie; Tindal, Gerald
2011-01-01
This technical report describes the process of development and piloting of reading comprehension measures that are appropriate for seventh-grade students as part of an online progress screening and monitoring assessment system, http://easycbm.com. Each measure consists of an original fictional story of approximately 1,600 to 1,900 words with 20…
Grussu, Pietro; Quatraro, Rosa Maria
2015-01-01
At this time, there is limited scientific knowledge about women who exclude themselves from screening programs for postnatal depression. In this retrospective descriptive study, we have sought to investigate the socio-demographic and psycho-social factors of women who withdraw from PND screening of their own accord. Study participants were 525 women attending antenatal classes who later took part in institutional routine screening for PND at the Consultorio Familiare Service of the National Health Service, Italy. The PND screening program consisted of the completion of the postpartum depression predictors inventory-revised and psychological well-being (PWB) questionnaires within eight to nine months of pregnancy, and Edinburgh Postnatal Depression Scale, GHQ-12 and PWB within six to eight weeks after childbirth. The Responders group was made up of 346 subjects - 65.9% of the total sample - who completed the entire program of screening for PND. The Non-Responders group, on the other hand, consisted of 179 subjects - 34.1% of the total sample - who, after childbirth, withdrew from the screening program. Compared to the Responders group, the Non-Responders group showed a greater number of subjects with marital dissatisfaction, and with unemployment as a stressful event. Health professionals who detect marital dissatisfaction and/or unemployment as a stressful event in pregnant women should bear in mind that these individuals, besides being at high risk for depression after delivery, will also tend to exclude themselves from screening for PND.
Appalakondaiah, S; Vaitheeswaran, G; Lebègue, S
2015-06-18
We have performed ab initio calculations for a series of energetic solids to explore their structural and electronic properties. To evaluate the ground state volume of these molecular solids, different dispersion correction methods were accounted in DFT, namely the Tkatchenko-Scheffler method (with and without self-consistent screening), Grimme's methods (D2, D3(BJ)), and the vdW-DF method. Our results reveal that dispersion correction methods are essential in understanding these complex structures with van der Waals interactions and hydrogen bonding. The calculated ground state volumes and bulk moduli show that the performance of each method is not unique, and therefore a careful examination is mandatory for interpreting theoretical predictions. This work also emphasizes the importance of quasiparticle calculations in predicting the band gap, which is obtained here with the GW approximation. We find that the obtained band gaps are ranging from 4 to 7 eV for the different compounds, indicating their insulating nature. In addition, we show the essential role of quasiparticle band structure calculations to correlate the gap with the energetic properties.
Theoretical L-shell Coster-Kronig energies 11 or equal to z or equal to 103
NASA Technical Reports Server (NTRS)
Chen, M. H.; Crasemann, B.; Huang, K. N.; Aoyagi, M.; Mark, H.
1976-01-01
Relativistic relaxed-orbital calculations of L-shell Coster-Kronig transition energies have been performed for all possible transitions in atoms with atomic numbers. Hartree-Fock-Slater wave functions served as zeroth-order eigenfunctions to compute the expectation of the total Hamiltonian. A first-order approximation to the local approximation was thus included. Quantum-electrodynamic corrections were made. Each transition energy was computed as the difference between results of separate self-consistent-field calculations for the initial, singly ionized state and the final two-hole state. The following quantities are listed: total transition energy, 'electric' (Dirac-Hartree-Fock-Slater) contribution, magnetic and retardation contributions, and contributions due to vacuum polarization and self energy.
Hong, Ie-Hong; Yen, Shang-Chieh; Lin, Fu-Shiang
2009-08-17
A well-ordered two-dimensional (2D) network consisting of two crossed Au silicide nanowire (NW) arrays is self-organized on a Si(110)-16 x 2 surface by the direct-current heating of approximately 1.5 monolayers of Au on the surface at 1100 K. Such a highly regular crossbar nanomesh exhibits both a perfect long-range spatial order and a high integration density over a mesoscopic area, and these two self-ordering crossed arrays of parallel-aligned NWs have distinctly different sizes and conductivities. NWs are fabricated with widths and pitches as small as approximately 2 and approximately 5 nm, respectively. The difference in the conductivities of two crossed-NW arrays opens up the possibility for their utilization in nanodevices of crossbar architecture. Scanning tunneling microscopy/spectroscopy studies show that the 2D self-organization of this perfect Au silicide nanomesh can be achieved through two different directional electromigrations of Au silicide NWs along different orientations of two nonorthogonal 16 x 2 domains, which are driven by the electrical field of direct-current heating. Prospects for this Au silicide nanomesh are also discussed.
Burger, Emily A; Sy, Stephen; Nygård, Mari; Kim, Jane J
2016-01-01
Background Human papillomavirus (HPV) testing allows women to self-collect cervico-vaginal cells at home (i.e., self-sampling). Using primary data from a randomized pilot study, we evaluated the long-term consequences and cost-effectiveness of using self-sampling to improve participation to routine cervical cancer screening in Norway. Methods We compared a strategy reflecting screening participation (using reminder letters) to strategies that involved mailing self-sampling device kits to women non-compliant to screening within a 5-year or 10-year period under two scenarios: A) self-sampling respondents had moderate under-screening histories, or B) respondents to self-sampling had moderate and severe under-screening histories. Model outcomes included quality-adjusted life-years (QALY) and lifetime costs. The ‘most cost-effective’ strategy was identified as the strategy just below $100,000 per QALY gained. Results Mailing self-sampling device kits to all women non-compliant to screening within a 5-year or 10-year period can be more effective and less costly than the current reminder letter policy; however, the optimal self-sampling strategy was dependent on the profile of self-sampling respondents. For example, ‘10-yearly self-sampling’ is preferred ($95,500 per QALY gained) if ‘5-yearly self-sampling’ could only attract moderate under-screeners; however, ‘5-yearly self-sampling’ is preferred if this strategy could additionally attract severe under-screeners. Conclusions Targeted self-sampling of non-compliers likely represents good value-for-money; however, the preferred strategy is contingent on the screening histories and compliance of respondents. Impact The magnitude of the health benefit and optimal self-sampling strategy is dependent on the profile and behavior of respondents. Health authorities should understand these factors prior to selecting and implementing a self-sampling policy. PMID:27624639
Burger, Emily A; Sy, Stephen; Nygård, Mari; Kim, Jane J
2017-01-01
Human papillomavirus (HPV) testing allows women to self-collect cervico-vaginal cells at home (i.e., self-sampling). Using primary data from a randomized pilot study, we evaluated the long-term consequences and cost-effectiveness of using self-sampling to improve participation to routine cervical cancer screening in Norway. We compared a strategy reflecting screening participation (using reminder letters) to strategies that involved mailing self-sampling device kits to women noncompliant to screening within a 5- or 10-year period under two scenarios: (A) self-sampling respondents had moderate under-screening histories, or (B) respondents to self-sampling had moderate and severe under-screening histories. Model outcomes included quality-adjusted life-years (QALY) and lifetime costs. The "most cost-effective" strategy was identified as the strategy just below $100,000 per QALY gained. Mailing self-sampling device kits to all women noncompliant to screening within a 5- or 10-year period can be more effective and less costly than the current reminder letter policy; however, the optimal self-sampling strategy was dependent on the profile of self-sampling respondents. For example, "10-yearly self-sampling" is preferred ($95,500 per QALY gained) if "5-yearly self-sampling" could only attract moderate under-screeners; however, "5-yearly self-sampling" is preferred if this strategy could additionally attract severe under-screeners. Targeted self-sampling of noncompliers likely represents good value-for-money; however, the preferred strategy is contingent on the screening histories and compliance of respondents. The magnitude of the health benefit and optimal self-sampling strategy is dependent on the profile and behavior of respondents. Health authorities should understand these factors prior to selecting and implementing a self-sampling policy. Cancer Epidemiol Biomarkers Prev; 26(1); 95-103. ©2016 AACR. ©2016 American Association for Cancer Research.
NASA Astrophysics Data System (ADS)
Steinbrink, Nicholas M. N.; Behrens, Jan D.; Mertens, Susanne; Ranitzsch, Philipp C.-O.; Weinheimer, Christian
2018-03-01
We investigate the sensitivity of the Karlsruhe Tritium Neutrino Experiment (KATRIN) to keV-scale sterile neutrinos, which are promising dark matter candidates. Since the active-sterile mixing would lead to a second component in the tritium β-spectrum with a weak relative intensity of order sin ^2θ ≲ 10^{-6}, additional experimental strategies are required to extract this small signature and to eliminate systematics. A possible strategy is to run the experiment in an alternative time-of-flight (TOF) mode, yielding differential TOF spectra in contrast to the integrating standard mode. In order to estimate the sensitivity from a reduced sample size, a new analysis method, called self-consistent approximate Monte Carlo (SCAMC), has been developed. The simulations show that an ideal TOF mode would be able to achieve a statistical sensitivity of sin ^2θ ˜ 5 × 10^{-9} at one σ , improving the standard mode by approximately a factor two. This relative benefit grows significantly if additional exemplary systematics are considered. A possible implementation of the TOF mode with existing hardware, called gated filtering, is investigated, which, however, comes at the price of a reduced average signal rate.
The usefulness of body image tests in the prevention of eating disorders.
Yamamoto, Chie; Uemoto, Masaharu; Shinfuku, Naotaka; Maeda, Kiyoshi
2007-01-01
Individual psychological factors such as mental conditions and self-esteem and family relational factors are thought to be predisposing factors in the development of eating disorders. In this study, we conducted a survey of 12-15 year-old public junior high school students to extract factors related to abnormal eating behavior and determine what information could be used by schools to prevent eating disorders. Self-descriptive surveys were distributed and collected during homeroom time at school. The survey consisted of the 26-item Eating Attitude Test (EAT-26) to measure the degree of abnormal eating behavior, Stunkard, Sorensen and Schlusinger's Body Image Scale to determine predisposing factors, the Family Adaptability and Cohesion Scale III (FACES III), General Health Questionnaire (GHQ), and Rosenberg's Self-Esteem Scale. 483 students (263 boys and 220 girls) participated in the survey. School-year height and weight data was used to calculate BMI. Approximately 7% of girls and 3% of boys showed clear indications of abnormal eating behavior. We found no direct relationship between abnormal eating behavior and family factors in this study, but an indirect relationship was suggested through other factors such as psychological complaints and self-esteem. There were relationships between abnormal eating behavior and the individual factors of psychological complaints, current and ideal body image, and low self-esteem. Furthermore, cluster analysis showed that there were students with high BMI who thought of themselves as fat, as well as students who perceived themselves as fat despite having average BMI. These students had a high frequency of abnormal eating behaviors, a great deal of psychological complaints, and low self-esteem. An understanding of BMI, along with body image, is essential for students who feel that they are overweight. Schools can practice preventative education by teaching these students about healthy body weight and by screening for the eating disorders that have become so rampant in our thin-worshiping culture.
[Common mental disorders and self-esteem in pregnancy: prevalence and associated factors].
Silva, Ricardo Azevedo da; Ores, Liliane da Costa; Mondin, Thaíse Campos; Rizzo, Raquel Nolasco; Moraes, Inácia Gomes da Silva; Jansen, Karen; Pinheiro, Ricardo Tavares
2010-09-01
The aim of this study was to assess the prevalence of common mental disorders and the association with self-esteem and other factors in pregnant women. A nested cross-sectional study was performed in a cohort of pregnant women treated in the public health system in Pelotas, Rio Grande do Sul State, Brazil. The Self-Reporting Questionnaire (SRQ-20) was used to screen for common mental disorders and the Rosenberg's Self-Esteem Scale for self-esteem. The sample consisted of 1,267 pregnant women with a mean age of 25 years (SD = 6.53). Mean self-esteem was 9.3 points (SD = 4.76), and prevalence of common mental disorders was 41.4%. Lower self-esteem was associated with higher odds of common mental disorders (p < 0.001). There was a significant association between higher prevalence of common mental disorders and low self-esteem.
ERIC Educational Resources Information Center
McPherson, Lyn; Ware, Robert S.; Carrington, Suzanne; Lennox, Nicholas
2017-01-01
Background: Adolescents with intellectual disability have high levels of unrecognized disease and inadequate health screening/promotion which might be addressed by improving health advocacy skills. Methods: A parallel-group cluster randomized controlled trial was conducted to investigate whether a health intervention package, consisting of…
Anisotropic nanocolloids: self-assembly, interfacial adsorption, and electrostatic screening
NASA Astrophysics Data System (ADS)
de Graaf, J.
2012-06-01
In this thesis we consider the influence of anisotropy on the behaviour of colloids using theory and simulations. The recent increase in the ability to synthesize anisotropic particles (cubes, caps, octapods, etc.) has led to samples of sufficient quality to perform self-assembly experiments. Our investigation is therefore particularly relevant to current and future experimental studies of colloids. We examine several topics for which shape anisotropy plays an important role: (1.) - Interfacial adsorption. We introduced the triangular-tessellation technique to approximate the surface areas and line length which are associated with a plane-particle intersection. Our method allowed us to determine the free energy of adsorption for a single irregular colloid with heterogeneous surface properties adsorbed at a flat liquid-liquid interface in the Pieranski approximation. Ellipsoids only adsorbed at the interface perpendicular to the interfacial normal. However, for cylinders we could find a metastable adsorption minimum corresponding to parallel adsorption. We also considered the possible time dependence of the adsorption process using simple dynamics. Finally, we studied the adsorption of truncated nanocubes with a contact-angle surface pattern and we observed that there are three prototypical equilibrium adsorption configurations for these particles. (2.) - Crystal-structure prediction. We extended an existing crystal-structure-prediction algorithm to predict structures for systems comprised of irregular hard particles. Using this technique we examined the high-density crystal structures for 17 irregular nonconvex shapes and we confirmed several mathematical conjectures for the packings of a large set of 142 convex polyhedra. We also proved that we have obtained the densest configurations for rhombicuboctahedra and rhombic enneacontrahedra, respectively. Moreover, we considered a family of truncated cubes, which interpolates between a cube and an octahedron, for which we obtained a fascinating richness in crystal structures. For the octahedron we determined the equation of state and we obtained a liquid, a (metastable) body-centred-cubic rotator phase, and a crystal phase. (3.) - Octapod hierarchical self-assembly. We analysed the recently observed hierarchical self-assembly of octapod-shaped nanocrystals (octapods) into three-dimensional (3D) superstructures. We constructed an empirical simulation model capable of reproducing the initial chain-formation step of the self-assembly. The van-der-Waals (vdW) interactions between octapods suspended in an (a)polar medium were obtained by means of a Hamaker-de-Boer-type integration and the nature of these interactions allowed us to justify elements of our empirical model. We used the theoretical vdW calculation, together with the experimental and simulation results, to formulate a mechanism which explained the observed self-assembly in terms of the solvent-dependence and directionality of the octapod-octapod interactions. (4.) - Ionic screening of charged Janus particles. We studied the screening of charged Janus particles in an electrolyte by primitive-model Monte Carlo (MC) simulations for a wide variety of parameters. We also introduced a method to compare these results to the predictions of nonlinear Poisson-Boltzmann (PB) theory. The comparison of MC and PB results allowed us to probe the range of validity of the PB approximation. This range of validity corresponds well to the range that was predicted by field-theoretical studies of homogeneously charged flat surfaces.
NASA Astrophysics Data System (ADS)
Mehmood, Faisal; Pachter, Ruth; Murphy, Neil R.; Johnson, Walter E.
2015-11-01
Prediction of the frequency-dependent dielectric function of thin films poses computational challenges, and at the same time experimental characterization by spectroscopic ellipsometry remains difficult to interpret because of changes in stoichiometry and surface morphology, temperature, thickness of the film, or substrate. In this work, we report calculations for titanium nitride (TiN), a promising material for plasmonic applications because of less loss and other practical advantages compared to noble metals. We investigated structural, electronic, and optical properties of stoichiometric bulk TiN, as well as of the TiN(100), TiN(110), and TiN(111) outermost surfaces. Density functional theory (DFT) and many-body GW methods (Green's (G) function-based approximation with screened Coulomb interaction (W)) were used, ranging from G0W0, GW0 to partially self-consistent sc-GW0, as well as the GW-BSE (Bethe-Salpeter equation) and time-dependent DFT (TDDFT) methods for prediction of the optical properties. Structural parameters and the band structure for bulk TiN were shown to be consistent with previous work. Calculated dielectric functions, plasma frequencies, reflectivity, and the electron energy loss spectrum demonstrated consistency with experiment at the GW0-BSE level. Deviations from experimental data are expected due to varying experimental conditions. Comparison of our results to spectroscopic ellipsometry data for realistic nanostructures has shown that although TDDFT may provide a computationally feasible level of theory in evaluation of the dielectric function, application is subject to validation with GW-BSE calculations.
Self-organization, the cascade model, and natural hazards.
Turcotte, Donald L; Malamud, Bruce D; Guzzetti, Fausto; Reichenbach, Paola
2002-02-19
We consider the frequency-size statistics of two natural hazards, forest fires and landslides. Both appear to satisfy power-law (fractal) distributions to a good approximation under a wide variety of conditions. Two simple cellular-automata models have been proposed as analogs for this observed behavior, the forest fire model for forest fires and the sand pile model for landslides. The behavior of these models can be understood in terms of a self-similar inverse cascade. For the forest fire model the cascade consists of the coalescence of clusters of trees; for the sand pile model the cascade consists of the coalescence of metastable regions.
NASA Technical Reports Server (NTRS)
Bauschlicher, C. W., Jr.; Silver, D. M.; Yarkony, D. R.
1980-01-01
The paper presents the multiconfiguration-self-consistent (MCSCF) and configuration state functions (CSF) for the low-lying electronic states of MgO. It was shown that simple description of these states was possible provided the 1 Sigma(+) states are individually optimized at the MCSCF level, noting that the 1(3 Sigma)(+) and 2(1 Sigma)(+) states which nominally result from the same electron occupation are separated energetically. The molecular orbitals obtained at this level of approximation should provide a useful starting point for extended configuration interaction calculations since they have been optimized for the particular states of interest.
Self-organization, the cascade model, and natural hazards
Turcotte, Donald L.; Malamud, Bruce D.; Guzzetti, Fausto; Reichenbach, Paola
2002-01-01
We consider the frequency-size statistics of two natural hazards, forest fires and landslides. Both appear to satisfy power-law (fractal) distributions to a good approximation under a wide variety of conditions. Two simple cellular-automata models have been proposed as analogs for this observed behavior, the forest fire model for forest fires and the sand pile model for landslides. The behavior of these models can be understood in terms of a self-similar inverse cascade. For the forest fire model the cascade consists of the coalescence of clusters of trees; for the sand pile model the cascade consists of the coalescence of metastable regions. PMID:11875206
NASA Astrophysics Data System (ADS)
Long, Xiaoyun; He, Lifen; Zhang, Yan; Ge, Mingqiao
2018-04-01
In this study, the self-lubricating layer consist of polytetrafluoroethylene (PTFE) micropowders and two types fluorocarbon acrylate resin were formed on the surface of geotextile, to improves the evenness and decreases the frictional angle value of geotextile surface. The surface and cross section morphology of geotextile were examined by scanning electron microscopy (SEM). It was determined that composite resin emulsion was evenly coated on the surface of geotextile, to form a even and complete self-lubricating layer, and it was strongly combined with the geotextile due to formation of the transition layer. The tensile fracture stress and strain values of samples were evaluated by mechanical properties measurement, the tensile fracture stress of the untreated and treated sample was approximately 5329 kN/m and 5452 kN/m while the elongation at the yield of them was approximately 85% to 83.9%, respectively. In addition, the frictional angle values of municipal solid waste (MSW)/geotextile interface was measured by the tilt table test, the values of untreated sample was 28.1° and 24.2° under the dry and moist condition, the values of treated sample was 16.2° and 9.8°, respectively.
Ma, Manman; Xu, Zhenli
2014-12-28
Electrostatic correlations and variable permittivity of electrolytes are essential for exploring many chemical and physical properties of interfaces in aqueous solutions. We propose a continuum electrostatic model for the treatment of these effects in the framework of the self-consistent field theory. The model incorporates a space- or field-dependent dielectric permittivity and an excluded ion-size effect for the correlation energy. This results in a self-energy modified Poisson-Nernst-Planck or Poisson-Boltzmann equation together with state equations for the self energy and the dielectric function. We show that the ionic size is of significant importance in predicting a finite self energy for an ion in an inhomogeneous medium. Asymptotic approximation is proposed for the solution of a generalized Debye-Hückel equation, which has been shown to capture the ionic correlation and dielectric self energy. Through simulating ionic distribution surrounding a macroion, the modified self-consistent field model is shown to agree with particle-based Monte Carlo simulations. Numerical results for symmetric and asymmetric electrolytes demonstrate that the model is able to predict the charge inversion at high correlation regime in the presence of multivalent interfacial ions which is beyond the mean-field theory and also show strong effect to double layer structure due to the space- or field-dependent dielectric permittivity.
NASA Astrophysics Data System (ADS)
Tovbin, Yu. K.
2018-06-01
An analysis is presented of one of the key concepts of physical chemistry of condensed phases: the theory self-consistency in describing the rates of elementary stages of reversible processes and the equilibrium distribution of components in a reaction mixture. It posits that by equating the rates of forward and backward reactions, we must obtain the same equation for the equilibrium distribution of reaction mixture components, which follows directly from deducing the equation in equilibrium theory. Ideal reaction systems always have this property, since the theory is of a one-particle character. Problems arise in considering interparticle interactions responsible for the nonideal behavior of real systems. The Eyring and Temkin approaches to describing nonideal reaction systems are compared. Conditions for the self-consistency of the theory for mono- and bimolecular processes in different types of interparticle potentials, the degree of deviation from the equilibrium state, allowing for the internal motions of molecules in condensed phases, and the electronic polarization of the reagent environment are considered within the lattice gas model. The inapplicability of the concept of an activated complex coefficient for reaching self-consistency is demonstrated. It is also shown that one-particle approximations for considering intermolecular interactions do not provide a theory of self-consistency for condensed phases. We must at a minimum consider short-range order correlations.
Gaines, Jean M; Narrett, Matthew; Parrish, John M
2010-01-01
Osteoporosis affects approximately 26% of women and 4% of men after the age of 65 years. However, the diffusion of knowledge about osteoporosis risk factors, prevention and treatment remains low. The purpose of this longitudinal study was to investigate the value of adding initial and refresher osteoporosis education classes to a bone health screening program. A convenience sample of 376 men (n = 62) and women (n = 314) over the age of 62 years was assigned randomly to the Screening plus Education (n =193) or Screening only (n = 183) groups. Participants in both study groups demonstrated an increase in knowledge about osteoporosis, regardless of group assignment and other factors, over the two years of the study. Self-reported calcium use increased for all women and for men in the education group from baseline to year one, with a decline thereafter. There was no effect on exercise behaviors. This study points out the critical need for a more comprehensive and personalized bone health program that includes more than classroom-based education. Copyright © 2010 Mosby, Inc. All rights reserved.
Self-consistent approach for neutral community models with speciation
NASA Astrophysics Data System (ADS)
Haegeman, Bart; Etienne, Rampal S.
2010-03-01
Hubbell’s neutral model provides a rich theoretical framework to study ecological communities. By incorporating both ecological and evolutionary time scales, it allows us to investigate how communities are shaped by speciation processes. The speciation model in the basic neutral model is particularly simple, describing speciation as a point-mutation event in a birth of a single individual. The stationary species abundance distribution of the basic model, which can be solved exactly, fits empirical data of distributions of species’ abundances surprisingly well. More realistic speciation models have been proposed such as the random-fission model in which new species appear by splitting up existing species. However, no analytical solution is available for these models, impeding quantitative comparison with data. Here, we present a self-consistent approximation method for neutral community models with various speciation modes, including random fission. We derive explicit formulas for the stationary species abundance distribution, which agree very well with simulations. We expect that our approximation method will be useful to study other speciation processes in neutral community models as well.
NASA Technical Reports Server (NTRS)
Zank, G. P.; Khabibrakhmanov, I. KH.; Story, T.
1993-01-01
A new two-fluid model which describes mass loading in the solar wind (e.g., the interaction of the solar wind with a cometary coma or the local interstellar medium) is presented. The self-consistent back-reaction of the mass-loaded ions is included through their effective scattering in low-frequency MHD turbulence and the invocation of a diffusive approximation. Such an approximation has the advantage of introducing self-consistent dissipation coefficients into the governing equations, thereby facilitating the investigation of the internal structure of shocks in mass-loading environments. To illustrate the utility of the new model, we consider the structure of cometary shocks in the hypersonic one-dimensional limit, finding that the incoming solar wind is slowed by both mass loading and the development of a large cometary ion pressure gradient. The shock is broadened and smoothed by the cometary ions with a thickness of the order of the cometary ion diffusion scale.
Anharmonic vibrational spectra and mode-mode couplings analysis of 2-aminopyridine
NASA Astrophysics Data System (ADS)
Faizan, Mohd; Alam, Mohammad Jane; Afroz, Ziya; Bhat, Sheeraz Ahmad; Ahmad, Shabbir
2018-01-01
Vibrational spectra of 2-aminopyridine (2AP) have been analyzed using the vibrational self-consistence field theory (VSCF), correlated corrected vibrational self-consistence field theory (CC-VSCF) and vibrational perturbation theory (VPT2) at B3LYP/6-311G(d,p) framework. The mode-mode couplings affect the vibrational frequencies and intensities. The coupling integrals between pairs of normal modes have been obtained on the basis of quartic force field (2MR-QFF) approximation. The overtone and combination bands are also assigned in the FTIR spectrum with the help of anharmonic calculation at VPT2 method. A statistical analysis of deviations shows that estimated anharmonic frequencies are closer to the experiment over harmonic approximation. Furthermore, the anharmonic correction has also been carried out for the dimeric structure of 2AP. The fundamental vibration bands have been assigned on the basis of potential energy distribution (PED) and visual look over the animated modes. Other important molecular properties such as frontier molecular orbitals and molecular electrostatics potential mapping have also been analyzed.
NASA Astrophysics Data System (ADS)
Gabovich, A. M.; Il'chenko, L. G.; Pashitskii, E. A.; Romanov, Yu. A.
1980-04-01
Using the Poisson equation Green function for a self-consistent field in a spatially inhomogeneous system, expressions for the electrostatic energy and screened charge interaction near the surface of a semi-infinite metal and a thin quantizing film are derived. It is shown that the decrease law and Friedel oscillation amplitude of adsorbed atom indirect interaction are determined by the electron spectrum character and the Fermi surface shape. The results obtained enable us to explain, in particular, the submonolayer adsorbed film structure on the W and Mo surfaces.
Short-range second order screened exchange correction to RPA correlation energies
NASA Astrophysics Data System (ADS)
Beuerle, Matthias; Ochsenfeld, Christian
2017-11-01
Direct random phase approximation (RPA) correlation energies have become increasingly popular as a post-Kohn-Sham correction, due to significant improvements over DFT calculations for properties such as long-range dispersion effects, which are problematic in conventional density functional theory. On the other hand, RPA still has various weaknesses, such as unsatisfactory results for non-isogyric processes. This can in parts be attributed to the self-correlation present in RPA correlation energies, leading to significant self-interaction errors. Therefore a variety of schemes have been devised to include exchange in the calculation of RPA correlation energies in order to correct this shortcoming. One of the most popular RPA plus exchange schemes is the second order screened exchange (SOSEX) correction. RPA + SOSEX delivers more accurate absolute correlation energies and also improves upon RPA for non-isogyric processes. On the other hand, RPA + SOSEX barrier heights are worse than those obtained from plain RPA calculations. To combine the benefits of RPA correlation energies and the SOSEX correction, we introduce a short-range RPA + SOSEX correction. Proof of concept calculations and benchmarks showing the advantages of our method are presented.
Short-range second order screened exchange correction to RPA correlation energies.
Beuerle, Matthias; Ochsenfeld, Christian
2017-11-28
Direct random phase approximation (RPA) correlation energies have become increasingly popular as a post-Kohn-Sham correction, due to significant improvements over DFT calculations for properties such as long-range dispersion effects, which are problematic in conventional density functional theory. On the other hand, RPA still has various weaknesses, such as unsatisfactory results for non-isogyric processes. This can in parts be attributed to the self-correlation present in RPA correlation energies, leading to significant self-interaction errors. Therefore a variety of schemes have been devised to include exchange in the calculation of RPA correlation energies in order to correct this shortcoming. One of the most popular RPA plus exchange schemes is the second order screened exchange (SOSEX) correction. RPA + SOSEX delivers more accurate absolute correlation energies and also improves upon RPA for non-isogyric processes. On the other hand, RPA + SOSEX barrier heights are worse than those obtained from plain RPA calculations. To combine the benefits of RPA correlation energies and the SOSEX correction, we introduce a short-range RPA + SOSEX correction. Proof of concept calculations and benchmarks showing the advantages of our method are presented.
Reconciling phase diffusion and Hartree-Fock approximation in condensate systems
NASA Astrophysics Data System (ADS)
Giorgi, Gian Luca; de Pasquale, Ferdinando
2012-01-01
Despite the weakly interacting regime, the physics of Bose-Einstein condensates is widely affected by particle-particle interactions. They determine quantum phase diffusion, which is known to be the main cause of loss of coherence. Studying a simple model of two interacting Bose systems, we show how to predict the appearance of phase diffusion beyond the Bogoliubov approximation, providing a self-consistent treatment in the framework of a generalized Hartree-Fock-Bogoliubov perturbation theory.
Pathirana, Thanya; Stoneman, Rebecca; Lamont, Amanda; Harris, Neil; Lee, Patricia
2018-04-01
Childhood obesity is rising in prevalence in Australia. This study aimed to evaluate the impact of the "Have Fun-Be Healthy" (HFBH) intervention, delivered in the Playgroup setting, to generate short term changes in dietary, physical activity and sedentary behaviours of children under 5 years and self-efficacy of parents and primary carers. This intervention consisted of eight structured cooking and physical play sessions delivered over a period of 8 weeks by trained facilitators. Pre- and post-intervention data collection was performed using survey questionnaires administered to parents and carers of children under 5 years from low socioeconomic backgrounds recruited through convenience sampling. A total of 640 pre-intervention surveys and 312 post-intervention surveys were returned. The matched response rate was 45.5%. There was an improvement in mean intake of healthy foods and mean physical activity with a decrease in mean intake of unhealthy food and mean screen time in children (P > .05). Following the intervention, parental/carer self-efficacy in promoting healthy eating and limiting screen time of children improved significantly (P < .05). Children's physical activity levels and consumption of healthy foods were positively correlated with parental/carer self-efficacy (P < .01) while screen time and consumption of unhealthy foods were negatively correlated (P < .01). HFBH intervention was successful in improving the dietary, physical activity and screen time in children and parental self-efficacy. SO WHAT?: Being amongst the first of its' kind in Australia, the findings of this study can have implications for developing and implementing similar future health promotion interventions in comparable settings. © 2017 Australian Health Promotion Association.
Purcell, Susan E; Rhea, Karen; Maier, Philip; First, Michael; Zweede, Lisa; Sinisterra, Manuela; Nunn, M Brad; Austin, Marie-Paule; Brodey, Inger S
2018-01-01
Background The Structured Clinical Interview for DSM (SCID) is considered the gold standard assessment for accurate, reliable psychiatric diagnoses; however, because of its length, complexity, and training required, the SCID is rarely used outside of research. Objective This paper aims to describe the development and initial validation of a Web-based, self-report screening instrument (the Screening Assessment for Guiding Evaluation-Self-Report, SAGE-SR) based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and the SCID-5-Clinician Version (CV) intended to make accurate, broad-based behavioral health diagnostic screening more accessible within clinical care. Methods First, study staff drafted approximately 1200 self-report items representing individual granular symptoms in the diagnostic criteria for the 8 primary SCID-CV modules. An expert panel iteratively reviewed, critiqued, and revised items. The resulting items were iteratively administered and revised through 3 rounds of cognitive interviewing with community mental health center participants. In the first 2 rounds, the SCID was also administered to participants to directly compare their Likert self-report and SCID responses. A second expert panel evaluated the final pool of items from cognitive interviewing and criteria in the DSM-5 to construct the SAGE-SR, a computerized adaptive instrument that uses branching logic from a screener section to administer appropriate follow-up questions to refine the differential diagnoses. The SAGE-SR was administered to healthy controls and outpatient mental health clinic clients to assess test duration and test-retest reliability. Cutoff scores for screening into follow-up diagnostic sections and criteria for inclusion of diagnoses in the differential diagnosis were evaluated. Results The expert panel reduced the initial 1200 test items to 664 items that panel members agreed collectively represented the SCID items from the 8 targeted modules and DSM criteria for the covered diagnoses. These 664 items were iteratively submitted to 3 rounds of cognitive interviewing with 50 community mental health center participants; the expert panel reviewed session summaries and agreed on a final set of 661 clear and concise self-report items representing the desired criteria in the DSM-5. The SAGE-SR constructed from this item pool took an average of 14 min to complete in a nonclinical sample versus 24 min in a clinical sample. Responses to individual items can be combined to generate DSM criteria endorsements and differential diagnoses, as well as provide indices of individual symptom severity. Preliminary measures of test-retest reliability in a small, nonclinical sample were promising, with good to excellent reliability for screener items in 11 of 13 diagnostic screening modules (intraclass correlation coefficient [ICC] or kappa coefficients ranging from .60 to .90), with mania achieving fair test-retest reliability (ICC=.50) and other substance use endorsed too infrequently for analysis. Conclusions The SAGE-SR is a computerized adaptive self-report instrument designed to provide rigorous differential diagnostic information to clinicians. PMID:29572204
Screening Ultrasound as an Adjunct to Mammography in Women with Mammographically Dense Breasts
Scheel, John R.; Lee, Janie M.; Sprague, Brian L.; Lee, Christoph I.; Lehman, Constance D.
2015-01-01
There is increasing interest in the potential benefits and harms of screening ultrasound to supplement mammographic screening of women with dense breast tissue. We review the current evidence regarding adjunctive screening breast ultrasound (US) and provide a summary for clinicians who counsel patients with dense breasts. We conducted a comprehensive literature review of published clinical trials and observational cohort studies assessing the efficacy of screening handheld US (HHUS) and automated breast US (ABUS) to supplement mammography among women with dense breasts. From a total of 189 peer-reviewed publications on the performance of screening US, 12 studies were relevant to our analysis. The reporting of breast cancer risk factors varied across studies; however, the study populations tended to be at greater than average risk for developing breast cancer. There is consistent evidence that adjunctive screening US detects more invasive cancers compared to mammography alone, but there is currently no evidence of associated long-term breast cancer mortality reduction. The studies also collectively found that US was associated with an additional 11.7–106.6 biopsies/1,000 examinations (Median 52.2), and detected an additional 0.3–7.7 cancers/1,000 examinations (Median 4.2). The associated number of unnecessary breast biopsies resulting from adjunct US screening exceeds that observed with screening mammography alone by approximately 5-fold. Adjunctive screening with ultrasound should also be considered in the context of screening mammography. It is important for clinicians to be aware that improvements in cancer detection in mammographically dense breasts have been achieved with the transition from film to digital mammography, reducing a limitation of film mammography. Clinicians should discuss breast density as one of several important breast cancer risk factors, consider the potential harms of adjunctive screening, and arrive at a shared decision consistent with each woman’s preferences and values. PMID:24959654
DOE Office of Scientific and Technical Information (OSTI.GOV)
Thompson, R. B.; Dion, S.; Konigslow, K. von
Self-consistent field theory equations are presented that are suitable for use as a coarse-grained model for DNA coated colloids, polymer-grafted nanoparticles and other systems with approximately isotropic interactions. The equations are generalized for arbitrary numbers of chemically distinct colloids. The advantages and limitations of such a coarse-grained approach for DNA coated colloids are discussed, as are similarities with block copolymer self-assembly. In particular, preliminary results for three species self-assembly are presented that parallel results from a two dimensional ABC triblock copolymer phase. The possibility of incorporating crystallization, dynamics, inverse statistical mechanics and multiscale modelling techniques are discussed.
A self-consistency check for unitary propagation of Hawking quanta
NASA Astrophysics Data System (ADS)
Baker, Daniel; Kodwani, Darsh; Pen, Ue-Li; Yang, I.-Sheng
2017-11-01
The black hole information paradox presumes that quantum field theory in curved space-time can provide unitary propagation from a near-horizon mode to an asymptotic Hawking quantum. Instead of invoking conjectural quantum-gravity effects to modify such an assumption, we propose a self-consistency check. We establish an analogy to Feynman’s analysis of a double-slit experiment. Feynman showed that unitary propagation of the interfering particles, namely ignoring the entanglement with the double-slit, becomes an arbitrarily reliable assumption when the screen upon which the interference pattern is projected is infinitely far away. We argue for an analogous self-consistency check for quantum field theory in curved space-time. We apply it to the propagation of Hawking quanta and test whether ignoring the entanglement with the geometry also becomes arbitrarily reliable in the limit of a large black hole. We present curious results to suggest a negative answer, and we discuss how this loss of naive unitarity in QFT might be related to a solution of the paradox based on the soft-hair-memory effect.
Lino, Valéria Teresa Saraiva; Portela, Margareth Crisóstomo; Camacho, Luiz Antonio Bastos; Rodrigues, Nadia Cristina Pinheiro; Andrade, Monica Kramer de Noronha; O'Dwyer, Gisele
2016-07-21
The objectives were to examine psychometric properties of a screening test for the elderly and to propose a protocol for use in primary care. The method consisted of four stages: (1) inter-evaluator reliability for performance tests and self-assessment questions for eight functions; (2) sensitivity and specificity of questions on depression and social support; (3) meeting of experts to select instrumental activities of daily living (IADL); and (4) elaboration of the protocol. Screening lasted 16 minutes. Inter-evaluator reliability was excellent for performance tests but poor for questions. Depression and social support showed satisfactory sensitivity and specificity (0.74/0.77 and 0.77/0.96). Four IADL were selected by more than 55% of the experts. Following the results, a screening protocol was elaborated that prioritized the use of performance tests, maintaining questions on mood, social support, and IADL. The study suggests better reproducibility of performance tests when compared to questions. For mood and social support, the questions may provide a first screening stage. The proposed protocol allows rapid screening of problems.
Validation of the Spanish Version of the Mammography-Specific Self-Efficacy Scale.
Jerome-D'Emilia, Bonnie; Suplee, Patricia; Akincigil, Ayse
2015-05-01
To consider psychometric estimates of the validity and reliability of the Spanish translation of a mammography-specific self-efficacy scale. A cross-sectional study. Three primarily Hispanic churches and a Hispanic community center in a low-income urban area of New Jersey. 153 low-income Hispanic women aged 40-85 years. The translated scale was administered to participants during a six-month period. Internal consistency, reliability, and construct and predictive validity were assessed. Demographic variables included income and insurance status. Outcome variables included total mammography-specific self-efficacy and having had a mammogram within the past two years. Preliminary evidence of reliability and validity were found, and predictive validity was demonstrated. The health needs of specific populations can be addressed only when research instruments have been appropriately validated and all relevant factors are considered. Diverse groups of low-income women face similar challenges and barriers in their efforts to get screened. Nurses are in an ideal position to help women with preventive care decision making (e.g., screening for breast cancer). Understanding how a woman's level of self-efficacy affects her decision making should be considered when counseling a client.
Sex disparities in diabetes process of care measures and self-care in high-risk patients.
Yu, Margaret K; Lyles, Courtney Rees; Bent-Shaw, Luis A; Young, Bessie A
2013-01-01
Patients with chronic diabetic complications experience high morbidity and mortality. Sex disparities in modifiable factors such as processes of care or self-care activities have not been explored in detail, particularly in these high-risk patients. Sex differences in processes of care and self-care activities were assessed in a cross-sectional analysis of the Pathways Study, an observational cohort of primary care diabetic patients from a managed care organization (N = 4,839). Compared to men, women had decreased odds of dyslipidemia screening (adjusted odds ratio (AOR) 0.73, 95% CI 0.62-0.85), reaching low-density lipoprotein goal (AOR 0.70, 95% CI 0.58-0.86), and statin use (AOR 0.69, 95% CI 0.58-0.81); women had 19% greater odds of reaching hemoglobin A1c <7% (95% CI 1.02-1.41). There were no sex differences in hemoglobin A1c testing, microalbuminuria screening, or angiotensin-converting enzyme inhibitor use. Women were less likely to report regular exercise but had better adherence to healthy diet, glucose monitoring, and self-foot examination compared to men. Patterns of sex differences were consistent in subjects with diabetic complications. Significant sex disparities exist in diabetes process of care measures and self-care, even amongst patients known to have chronic diabetic complications.
Leung, Doris Y. P.; Chow, Ka Ming; Lo, Sally W. S.; So, Winnie K. W.; Chan, Carmen W. H.
2016-01-01
Colorectal cancer (CRC) is a major health problem in Asia. It has been reported that the Chinese are more susceptible to CRC than many other ethnic groups. Screening for CRC is a cost-effective prevention and control strategy; however, the screening rates among the Chinese are sub-optimal. We conducted a review to identify the factors associated with CRC screening participation among Chinese people. Twenty-two studies that examined the factors related to CRC screening behaviors among the Chinese were identified through five databases. Seven factors were consistently reported to influence CRC screening behaviors in at least one of the studies: socio-demographic characteristics (educational level, health insurance, and knowledge about CRC and its screening); psychological factors (perceived severity of CRC, susceptibility of having CRC, and barriers to screening); and contact with medical provider (physician recommendation). The evidence base for many of these relationships is quite limited. Furthermore, the associations of many factors, including age, gender, income, cancer worry/fear, and self-efficacy with CRC screening behaviors, were mixed or inconsistent across these studies, thereby indicating that more studies are needed in this area. PMID:27196920
Promoting self-exploration and function through an individualized power mobility training program.
Kenyon, Lisa K; Farris, John; Brockway, Kaelee; Hannum, Nanette; Proctor, Kevin
2015-01-01
This case report describes the development and implementation of an intervention program that used a Power Wheelchair Trainer (Trainer) to enable an individual with severe impairments to participate in power mobility training. The participant was an 18 year-old female with spastic quadriplegic cerebral palsy, Gross Motor Function Classification Level V. The examination included the Power Mobility Screen and the Caregiver Priorities & Child Health Index of Life with Disabilities (CPCHILD). Switches on the participant's headrest provided control of the Trainer. Intervention consisted of power mobility training in an engaging environment that was set-up to focus on specific power mobility skills. Scores on the Power Mobility Screen and the CPCHILD were higher after intervention. The outcomes of this case report appear to support the use of the Trainer, which allowed the participant to practice power mobility skills and participate in self-exploration of her environment.
Etzioni, Ruth; Gulati, Roman; Cooperberg, Matt R; Penson, David M; Weiss, Noel S; Thompson, Ian M
2013-04-01
The US Preventive Services Task Force recently recommended against prostate-specific antigen screening for prostate cancer based primarily on evidence from the European Randomized Study of Screening for Prostate Cancer (ERSPC) and the US Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. : To examine limitations of basing screening policy on evidence from screening trials. We reviewed published modeling studies that examined population and trial data. The studies (1) project the roles of screening and changes in primary treatment in the US mortality decline; (2) extrapolate the ERSPC mortality reduction to the long-term US setting; (3) estimate overdiagnosis based on US incidence trends; and (4) quantify the impact of control arm screening on PLCO mortality results. Screening plausibly explains 45% and changes in primary treatment can explain 33% of the US prostate cancer mortality decline. Extrapolating the ERSPC results to the long-term US setting implies an absolute mortality reduction at least 5 times greater than that observed in the trial. Approximately 28% of screen-detected cases are overdiagnosed in the United States versus 58% of screen-detected cases suggested by the ERSPC results. Control arm screening can explain the null result in the PLCO trial. Modeling studies indicate that population trends and trial results extended to the long-term population setting are consistent with greater benefit of prostate-specific antigen screening-and more favorable harm-benefit tradeoffs-than has been suggested by empirical trial evidence.
Acceptability of unsupervised HPV self-sampling using written instructions.
Waller, J; McCaffery, K; Forrest, S; Szarewski, A; Cadman, L; Austin, J; Wardle, J
2006-01-01
The study measured the acceptability of self-sampling for human papillomavirus (HPV) testing in the context of cervical cancer screening. Women carried out self-sampling unsupervised, using a written instruction sheet. Participants were women attending either a family planning clinic or a primary care trust for routine cervical screening. Women (n = 902) carried out self-sampling for HPV testing and then a clinician did a routine cervical smear and HPV test. Immediately after having the two tests, participants completed a measure of acceptability for both tests, and answered questions about ease of using the instruction sheet and willingness to use self-sampling in the future. The majority of women found self-sampling more acceptable than the clinician-administered test, but there was a lack of confidence that the test had been done correctly. Significant demographic differences in attitudes were found, with married women having more favourable attitudes towards self-sampling than single women, and Asian women having more negative attitudes than women in other ethnic groups. Intention to use self-sampling in the future was very high across all demographic groups. Self-sampling for HPV testing was highly acceptable in this large and demographically diverse sample, and women were able to carry out the test alone, using simple written instructions. Consistent with previous studies, women were concerned about doing the test properly and this issue will need to be addressed if self-sampling is introduced. More work is needed to see whether the demographic differences we found are robust and to identify reasons for lower acceptability among single women and those from Asian background.
Smartlowit-Briggs, Lucy; Pearson, Cynthia; Whitefoot, Patricia; Altamirano, Bianca N.; Womack, Michelle; Bastin, Marie; Dombrowski, Julia C.
2017-01-01
Background Rates of chlamydial infection in American Indian/Alaska Native women in the United States are approximately 4-fold those in non-Hispanic white women. We conducted a community-based survey of self-identified American Indian/Alaska Native women 14 to 25 years of age on a reservation in the Northwestern United States to inform a chlamydia screening strategy. Methods The anonymous survey assessed respondents’ knowledge, perceptions, and preferences related to chlamydia screening, results receipt, and partner notification. We recruited women using respondent-driven sampling, school-based sampling, and direct recruitment through social media and fliers. Participants in schools completed the survey as a paper-based, self-administered survey. Other participants could complete the survey in person, by phone as an interviewer-administered survey, or online. Results We recruited 162 participants, most in schools (n = 83; 51%) or by peer referral (n = 55; 34%). Only 1 woman completed the survey online. Thirty-one respondents (19%) reported a history of an unplanned first pregnancy, and 19 (12%) reported a history of a diagnosed sexually transmitted disease. Most women (n = 98; 63%) recognized the potential impact of Chlamydia trachomatis on fertility. The preferred site for chlamydia screening was the Indian Health Service Clinic (n = 114; 70%), but 79 women (41%) would accept a C. trachomatis test at a nonclinical testing site. Of the 56 women (35%) who would accept home testing, most preferred to get the test kit from a clinic. Conclusions Our results suggest that Indian Health Service efforts to increase chlamydia screening in the clinic and through outreach may be more successful than promotion of home testing in this population. PMID:27196261
Smartlowit-Briggs, Lucy; Pearson, Cynthia; Whitefoot, Patricia; Altamirano, Bianca N; Womack, Michelle; Bastin, Marie; Dombrowski, Julia C
2016-06-01
Rates of chlamydial infection in American Indian/Alaska Native women in the United States are approximately 4-fold those in non-Hispanic white women. We conducted a community-based survey of self-identified American Indian/Alaska Native women 14 to 25 years of age on a reservation in the Northwestern United States to inform a chlamydia screening strategy. The anonymous survey assessed respondents' knowledge, perceptions, and preferences related to chlamydia screening, results receipt, and partner notification. We recruited women using respondent-driven sampling, school-based sampling, and direct recruitment through social media and fliers. Participants in schools completed the survey as a paper-based, self-administered survey. Other participants could complete the survey in person, by phone as an interviewer-administered survey, or online. We recruited 162 participants, most in schools (n = 83; 51%) or by peer referral (n = 55; 34%). Only 1 woman completed the survey online. Thirty-one respondents (19%) reported a history of an unplanned first pregnancy, and 19 (12%) reported a history of a diagnosed sexually transmitted disease. Most women (n = 98; 63%) recognized the potential impact of Chlamydia trachomatis on fertility. The preferred site for chlamydia screening was the Indian Health Service Clinic (n = 114; 70%), but 79 women (41%) would accept a C. trachomatis test at a nonclinical testing site. Of the 56 women (35%) who would accept home testing, most preferred to get the test kit from a clinic. Our results suggest that Indian Health Service efforts to increase chlamydia screening in the clinic and through outreach may be more successful than promotion of home testing in this population.
Mbaba, Mary; Brown, Shan-Estelle; Wooditch, Alese; Kiss, Marissa; Murphy, Amy; Kumari, Suneeta; Taxman, Faye; Altice, Frederick; Lawson, William B; Springer, Sandra A
2018-01-15
Individuals involved in the criminal justice system have disproportionately high rates of psychiatric disorders when compared to the general U.S. If left untreated, the likelihood of subsequent arrest increases and risk for adverse health consequences is great, particularly among opioid users. To explore the prevalence, characteristics, and treatment of mood disorders among justice involved opioid-dependent populations. The current study enrolled 258 treatment-seeking opioid-dependent individuals under community-based criminal justice supervision (e.g., probation, parole) screened from the larger parent study, Project STRIDE, a seek/test/treat randomized control trial (RCT) examining HIV and opioid use treatment. During baseline, individuals were screened for depression using the Patient Health Questionnaire-9 (PHQ-9) and screened for bipolar disorder using the Mood Disorder Questionnaire (MDQ) tool. Overall, 78 (30%) participants screened positive for moderate to severe depression and 54 (21%) screened positive for bipolar disorder. Participants self-reported mood disorders at higher rates than they screened positive for these conditions. Participants screening positive for these conditions experienced significantly greater family, legal, and medical problems on the Addiction Severity Index-Lite (ASI-Lite) than those who did not screen positive. Incidence of a lifetime suicide attempt was found to be associated with a positive screen for both mood disorders. Prescribed psychotropic treatment utilization was similar among those who screened positive for depression or bipolar disorder with approximately 38% reporting taking medication. Findings suggest universal mood disorder screening to improve comprehensive psychiatric care and treatment of opioid-dependent justice-involved individuals.
Comparing the effectiveness of TWEAK and T-ACE in determining problem drinkers in pregnancy.
Sarkar, M; Einarson, T; Koren, G
2010-01-01
The TWEAK and T-ACE screening tools are validated methods of identifying problem drinking in a pregnant population. The objective of this study was to compare the effectiveness of the TWEAK and T-ACE screening tools in identifying problem drinking using traditional cut-points (CP). Study participants consisted of women calling the Motherisk Alcohol Helpline for information regarding their alcohol use in pregnancy. In this cohort, concerns surrounding underreporting are not likely as women self-report their alcohol consumption. Participant's self-identification, confirmed by her amount of alcohol use, determined whether she was a problem drinker or not. The TWEAK and T-ACE tools were administered on both groups and subsequent analysis was done to determine if one tool was more effective in predicting problem drinking. The study consisted of 75 problem and 100 non-problem drinkers. Using traditional CP, the TWEAK and T-ACE tools both performed similarly at identifying potential at-risk women (positive predictive value = 0.54), with very high sensitivity rates (100-99% and 100-93%, respectively) but poor specificity rates (36-43% and 19-34%, respectively). Upon comparison, there was no statistical difference in the effectiveness for one test performing better than next using either CP of 2 (P = 0.66) or CP of 3 (P = 0.38). Despite the lack of difference in performance, improved specificity associated with TWEAK suggests that it may be better suited to screen at-risk populations seeking advice from a helpline.
The association between self-reported anxiety symptoms and suicidality.
Diefenbach, Gretchen J; Woolley, Stephen B; Goethe, John W
2009-02-01
This cross-sectional study assessed the association between self-reported anxiety symptoms and self-reported suicidality among a mixed diagnostic sample of psychiatric outpatients. Data were obtained from chart review of 2,778 outpatients who completed a routine diagnostic clinical interview and a standardized self-report of psychiatric symptoms on admission. Bivariate analyses indicated that those with >or= moderate anxiety symptoms were over three times as likely to report >or= moderate difficulty with suicidality. Self-reported anxiety symptoms were associated with a 2-fold increased likelihood of reporting suicidality after controlling for confounding (demographics, depressive symptoms, and diagnoses). These data are consistent with a growing literature demonstrating an association between anxiety symptoms and suicidality, and suggest that this association is not accounted for by coexisting mood symptoms or diagnoses. A single item, self-report may be a useful screening tool for symptoms that are pertinent to assessment of suicide risk.
Self-consistent gyrokinetic modeling of neoclassical and turbulent impurity transport
NASA Astrophysics Data System (ADS)
Estève, D.; Sarazin, Y.; Garbet, X.; Grandgirard, V.; Breton, S.; Donnel, P.; Asahi, Y.; Bourdelle, C.; Dif-Pradalier, G.; Ehrlacher, C.; Emeriau, C.; Ghendrih, Ph.; Gillot, C.; Latu, G.; Passeron, C.
2018-03-01
Trace impurity transport is studied with the flux-driven gyrokinetic GYSELA code (Grandgirard et al 2016 Comput. Phys. Commun. 207 35). A reduced and linearized multi-species collision operator has been recently implemented, so that both neoclassical and turbulent transport channels can be treated self-consistently on an equal footing. In the Pfirsch-Schlüter regime that is probably relevant for tungsten, the standard expression for the neoclassical impurity flux is shown to be recovered from gyrokinetics with the employed collision operator. Purely neoclassical simulations of deuterium plasma with trace impurities of helium, carbon and tungsten lead to impurity diffusion coefficients, inward pinch velocities due to density peaking, and thermo-diffusion terms which quantitatively agree with neoclassical predictions and NEO simulations (Belli et al 2012 Plasma Phys. Control. Fusion 54 015015). The thermal screening factor appears to be less than predicted analytically in the Pfirsch-Schlüter regime, which can be detrimental to fusion performance. Finally, self-consistent nonlinear simulations have revealed that the tungsten impurity flux is not the sum of turbulent and neoclassical fluxes computed separately, as is usually assumed. The synergy partly results from the turbulence-driven in-out poloidal asymmetry of tungsten density. This result suggests the need for self-consistent simulations of impurity transport, i.e. including both turbulence and neoclassical physics, in view of quantitative predictions for ITER.
Compton scattering collision module for OSIRIS
NASA Astrophysics Data System (ADS)
Del Gaudio, Fabrizio; Grismayer, Thomas; Fonseca, Ricardo; Silva, Luís
2017-10-01
Compton scattering plays a fundamental role in a variety of different astrophysical environments, such as at the gaps of pulsars and the stagnation surface of black holes. In these scenarios, Compton scattering is coupled with self-consistent mechanisms such as pair cascades. We present the implementation of a novel module, embedded in the self-consistent framework of the PIC code OSIRIS 4.0, capable of simulating Compton scattering from first principles and that is fully integrated with the self-consistent plasma dynamics. The algorithm accounts for the stochastic nature of Compton scattering reproducing without approximations the exchange of energy between photons and unbound charged species. We present benchmarks of the code against the analytical results of Blumenthal et al. and the numerical solution of the linear Kompaneets equation and good agreement is found between the simulations and the theoretical models. This work is supported by the European Research Council Grant (ERC- 2015-AdG 695088) and the Fundao para a Céncia e Tecnologia (Bolsa de Investigao PD/BD/114323/2016).
Self-consistent perturbation theory for two dimensional twisted bilayers
NASA Astrophysics Data System (ADS)
Shirodkar, Sharmila N.; Tritsaris, Georgios A.; Kaxiras, Efthimios
Theoretical modeling and ab-initio simulations of two dimensional heterostructures with arbitrary angles of rotation between layers involve unrealistically large and expensive calculations. To overcome this shortcoming, we develop a methodology for weakly interacting heterostructures that treats the effect of one layer on the other as perturbation, and restricts the calculations to their primitive cells. Thus, avoiding computationally expensive supercells. We start by approximating the interaction potential between the twisted bilayers to that of a hypothetical configuration (viz. ideally stacked untwisted layers), which produces band structures in reasonable agreement with full-scale ab-initio calculations for commensurate and twisted bilayers of graphene (Gr) and Gr/hexagonal boron nitride (h-BN) heterostructures. We then self-consistently calculate the charge density and hence, interaction potential of the heterostructures. In this work, we test our model for bilayers of various combinations of Gr, h-BN and transition metal dichalcogenides, and discuss the advantages and shortcomings of the self-consistently calculated interaction potential. Department of Physics, Harvard University, Cambridge, Massachusetts 02138, USA.
Jäger, B; Schmid-Ott, G; Ernst, G; Dölle-Lange, E; Sack, M
2012-06-01
The aim of this study was to construct and validate a short self-rating questionnaire for the assessment of ego functions and ability of self regulation. An item pool of 120 items covering 6 postulated dimensions was reduced by two steps in independent samples (n = 136 + 470) via factor and item analyses to the final version consisting of 35 items. The 5 resulting questionnaire scales "interpersonal disturbances", "frustration tolerance and impulse control", "identity disturbances", "affect differentiation and affect tolerance" and "self-esteem" were well interpretable and showed in confirmatory factor analysis the best fit to the data (CHI²/df = 3.48; RMSEA = 0.73). Total scores were found to differentiate well between diagnostic groups of patients with more or less ego pathology (FANOVA = 9.8; df = 11; p < 0.001), thus proving good concurrent validity. Reliability was shown by testing internal consistency and test-retest correlations. The "Hannover self-regulation questionnaire" (HSRQ) evidently is an appropriate and reliable screening instrument in order to assess ego functions and capacities of self regulation in an economic and user-friendly means. The scale structure allows differentiated diagnostics of weak vs. stable ego functions and may be used for detailed therapy planning. © Georg Thieme Verlag KG Stuttgart · New York.
Lampard, Amy M; Jurkowski, Janine M; Davison, Kirsten K
2013-10-01
Parents' rules regarding child television, DVD, video game, and computer use (screen time) have been associated with lower screen use in children. This study aimed to identify modifiable correlates of this behavior by examining social-cognitive predictors of parents' restriction of child screen time. Low-income parents (N = 147) of preschool-aged children (2-6 years) completed self-administered questionnaires examining parent and child screen time, parent restriction of screen time, self-efficacy to restrict screen time, and beliefs about screen time. Structural equation modeling results indicated that greater self-efficacy to restrict screen time (β = .29, p = .016) and greater perceived importance of restricting child screen use (β = .55, p < .001) were associated with greater restriction of child screen use, after controlling for parent screen time. Family-based interventions that consider broader attitudinal factors around child screen time may be necessary to engage parents in restricting screen use.
Self-Management Skills in Chronic Disease Management: What Role Does Health Literacy Have?
Mackey, Laura M; Doody, Catherine; Werner, Erik L; Fullen, Brona
2016-08-01
Self-management-based interventions can lead to improved health outcomes in people with chronic diseases, and multiple patient characteristics are associated with the development of self-management behaviors. Low health literacy (HL) has been implicated in poorer self-management behaviors and increased costs to health services. However, the mechanisms behind this relationship remain unclear. Therefore, the aim of the current review is to assess the association between HL and patient characteristics related to self-management behaviors (i.e., disease-related knowledge, beliefs, and self-efficacy). The review comprised 3 phases: 1) database searches, 2) eligibility screening, and 3) study quality assessment and strength of evidence. Inclusion criteria specified that a valid HL screening tool was used, that at least one self-management behavior was assessed, and that patients had a chronic condition. An initial search generated a total of 712 articles, of which 31 studies fulfilled the eligibility criteria. A consistent association was found between low HL and poorer disease-related knowledge in respiratory diseases, diabetes, and multiple disease categories. A significant association between low HL and poorer self-efficacy was reported in cardiovascular diseases, diabetes, human immunodeficiency virus, and multiple disease categories. HL was significantly associated with poorer beliefs in respiratory, musculoskeletal, and cardiovascular diseases. The findings from the current review suggest that low HL may affect behaviors necessary for the development of self-management skills. Given that self-management strategies are core components for effective treatment of a range of chronic diseases, low HL poses a considerable health concern. Further research is needed to understand the mediating influence of HL on disease-related knowledge, self-efficacy, and beliefs. From this, HL-sensitive, self-management interventions ought to be devised and implemented. © The Author(s) 2016.
Thermodynamically self-consistent theory for the Blume-Capel model.
Grollau, S; Kierlik, E; Rosinberg, M L; Tarjus, G
2001-04-01
We use a self-consistent Ornstein-Zernike approximation to study the Blume-Capel ferromagnet on three-dimensional lattices. The correlation functions and the thermodynamics are obtained from the solution of two coupled partial differential equations. The theory provides a comprehensive and accurate description of the phase diagram in all regions, including the wing boundaries in a nonzero magnetic field. In particular, the coordinates of the tricritical point are in very good agreement with the best estimates from simulation or series expansion. Numerical and analytical analysis strongly suggest that the theory predicts a universal Ising-like critical behavior along the lambda line and the wing critical lines, and a tricritical behavior governed by mean-field exponents.
Self-assembled nanogaps for molecular electronics.
Tang, Qingxin; Tong, Yanhong; Jain, Titoo; Hassenkam, Tue; Wan, Qing; Moth-Poulsen, Kasper; Bjørnholm, Thomas
2009-06-17
A nanogap for molecular devices was realized using solution-based self-assembly. Gold nanorods were assembled to gold nanoparticle-coated conducting SnO2:Sb nanowires via thiol end-capped oligo(phenylenevinylene)s (OPVs). The molecular gap was easily created by the rigid molecule itself during self-assembly and the gap length was determined by the molecule length. The gold nanorods and gold nanoparticles, respectively covalently bonded at the two ends of the molecule, had very small dimensions, e.g. a width of approximately 20 nm, and hence were expected to minimize the screening effect. The ultra-long conducting SnO2:Sb nanowires provided the bridge to connect one of the electrodes of the molecular device (gold nanoparticle) to the external circuit. The tip of the atomic force microscope (AFM) was contacted onto the other electrode (gold nanorod) for the electrical measurement of the OPV device. The conductance measurement confirmed that the self-assembly of the molecules and the subsequent self-assembly of the gold nanorods was a feasible method for the fabrication of the nanogap of the molecular devices.
Contribution of Dielectric Screening to the Total Capacitance of Few-Layer Graphene Electrodes.
Zhan, Cheng; Jiang, De-en
2016-03-03
We apply joint density functional theory (JDFT), which treats the electrode/electrolyte interface self-consistently, to an electric double-layer capacitor (EDLC) based on few-layer graphene electrodes. The JDFT approach allows us to quantify a third contribution to the total capacitance beyond quantum capacitance (CQ) and EDL capacitance (CEDL). This contribution arises from the dielectric screening of the electric field by the surface of the few-layer graphene electrode, and we therefore term it the dielectric capacitance (CDielec). We find that CDielec becomes significant in affecting the total capacitance when the number of graphene layers in the electrode is more than three. Our investigation sheds new light on the significance of the electrode dielectric screening on the capacitance of few-layer graphene electrodes.
Evaluating strategies and costs to recruit smokeless tobacco users.
Boyle, Raymond G; Enstad, Chris; Asche, Stephen E; Thoele, Merry J; Sherwood, Nancy E
2007-12-01
We recruited smokeless tobacco users throughout Minnesota to participate in a trial testing telephone counseling versus a written self-help manual for cessation. This paper describes the recruitment strategies applied on a state-wide basis. We established a recruitment tracking system to monitor weekly rates of screened callers and returned consents, allowing us to adjust future recruitment efforts. Screening was completed with 783 callers, with 406 subjects enrolled. Overall 44% of initial contacts and 52% of those screened enrolled in the study. The overall average cost per consented subject was $99. Sports talk radio, small print ads, and newspaper articles based on press releases were consistently effective channels for recruitment. The overall cost was expensive but reflected the geographic diversity of recruitment and the prevalence of oral snuff use.
Screen Time, Physical Activity and Self-Esteem in Children: The Ulm Birth Cohort Study.
Braig, Stefanie; Genuneit, Jon; Walter, Viola; Brandt, Stephanie; Wabitsch, Martin; Goldbeck, Lutz; Brenner, Hermann; Rothenbacher, Dietrich
2018-06-16
Screen time is a central activity of children’s daily life and jeopardizes mental health. However, results appear inconclusive and are often based on small cross-sectional studies. We aimed to investigate the temporal sequence of the association between screen time and self-esteem taking into account further indirect effects through family or friendship relationship. In our population-based birth cohort study (baseline November 2000⁻November 2001, Ulm, Germany), these relationships were explored in n = 519 11- and 13-year-old children and their parents who both provided information on children’s screen time: time spent watching television or videos (TV), time spent on computers, video game consoles, mobile devices, or cell phones; so called “other screen time”, and children’s self-esteem (KINDL-R). Time watching TV (self-reported) at age 11 was negatively associated with girls’ self-esteem at the same age but positively with an increase of self-esteem between age 11 and 13. However, the latter association was restricted to low to moderate TV viewers. In boys, a higher increase of other screen time between age 11 and age 13 was associated with lower self-reported self-esteem at age 13. Additionally, friendship relationship mediated the association between watching TV and self-esteem in girls. For parental reports similar associations were observed. These findings indicate that time sequence and potential mediators need further investigation in cohort studies with multiple assessments of screen time and self-esteem.
Screening and clustering of sparse regressions with finite non-Gaussian mixtures.
Zhang, Jian
2017-06-01
This article proposes a method to address the problem that can arise when covariates in a regression setting are not Gaussian, which may give rise to approximately mixture-distributed errors, or when a true mixture of regressions produced the data. The method begins with non-Gaussian mixture-based marginal variable screening, followed by fitting a full but relatively smaller mixture regression model to the selected data with help of a new penalization scheme. Under certain regularity conditions, the new screening procedure is shown to possess a sure screening property even when the population is heterogeneous. We further prove that there exists an elbow point in the associated scree plot which results in a consistent estimator of the set of active covariates in the model. By simulations, we demonstrate that the new procedure can substantially improve the performance of the existing procedures in the content of variable screening and data clustering. By applying the proposed procedure to motif data analysis in molecular biology, we demonstrate that the new method holds promise in practice. © 2016, The International Biometric Society.
Inclusion-Based Effective Medium Models for the Permeability of a 3D Fractured Rock Mass
NASA Astrophysics Data System (ADS)
Ebigbo, A.; Lang, P. S.; Paluszny, A.; Zimmerman, R. W.
2015-12-01
Following the work of Saevik et al. (Transp. Porous Media, 2013; Geophys. Prosp., 2014), we investigate the ability of classical inclusion-based effective medium theories to predict the macroscopic permeability of a fractured rock mass. The fractures are assumed to be thin, oblate spheroids, and are treated as porous media in their own right, with permeability kf, and are embedded in a homogeneous matrix having permeability km. At very low fracture densities, the effective permeability is given exactly by a well-known expression that goes back at least as far as Fricke (Phys. Rev., 1924). For non-trivial fracture densities, an effective medium approximation must be employed. We have investigated several such approximations: Maxwell's method, the differential method, and the symmetric and asymmetric versions of the self-consistent approximation. The predictions of the various approximate models are tested against the results of explicit numerical simulations, averaged over numerous statistical realizations for each set of parameters. Each of the various effective medium approximations satisfies the Hashin-Shtrikman (H-S) bounds. Unfortunately, these bounds are much too far apart to provide quantitatively useful estimates of keff. For the case of zero matrix permeability, the well-known approximation of Snow, which is based on network considerations rather than a continuum approach, is shown to essentially coincide with the upper H-S bound, thereby proving that the commonly made assumption that Snow's equation is an "upper bound" is indeed correct. This problem is actually characterized by two small parameters, the aspect ratio of the spheroidal fractures, α, and the permeability ratio, κ = km/kf. Two different regimes can be identified, corresponding to α < κ and κ < α, and expressions for each of the effective medium approximations are developed in both regimes. In both regimes, the symmetric version of the self-consistent approximation is the most accurate.
Self consistent field theory of virus assembly
NASA Astrophysics Data System (ADS)
Li, Siyu; Orland, Henri; Zandi, Roya
2018-04-01
The ground state dominance approximation (GSDA) has been extensively used to study the assembly of viral shells. In this work we employ the self-consistent field theory (SCFT) to investigate the adsorption of RNA onto positively charged spherical viral shells and examine the conditions when GSDA does not apply and SCFT has to be used to obtain a reliable solution. We find that there are two regimes in which GSDA does work. First, when the genomic RNA length is long enough compared to the capsid radius, and second, when the interaction between the genome and capsid is so strong that the genome is basically localized next to the wall. We find that for the case in which RNA is more or less distributed uniformly in the shell, regardless of the length of RNA, GSDA is not a good approximation. We observe that as the polymer-shell interaction becomes stronger, the energy gap between the ground state and first excited state increases and thus GSDA becomes a better approximation. We also present our results corresponding to the genome persistence length obtained through the tangent-tangent correlation length and show that it is zero in case of GSDA but is equal to the inverse of the energy gap when using SCFT.
Hoare, Erin; Milton, Karen; Foster, Charlie; Allender, Steven
2016-10-08
With technological developments and modernised sedentary lifestyles has come an increase in diseases associated with inactivity such as obesity and other non-communicable diseases. Emerging evidence suggests that time spent sedentary may also interact with mental health. This systematic review examined the associations between sedentary behaviour and mental health problems among adolescents. This systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and applied a quality assessment tool for quantitative studies to identity best available evidence. Following stringent search strategy of the databases; Cumulative Index to Nursing and Allied Health Literature, Global Health, Health Source: Nursing and Academic Edition, MEDLINE, PsychARTICLES and PsycINFO, we identified 32 articles eligible for review. All studies reported leisure screen time among adolescents, and two thirds of identified studies examined depressive symptomatology. Other mental health measures were; anxiety symptoms, self-esteem, suicide ideation, loneliness, stress, and psychological distress. Strong consistent evidence was found for the relationship between both depressive symptomatology and psychological distress, and time spent using screens for leisure. Moderate evidence supported the relationship between low self-esteem and screen use. Poorer mental health status was found among adolescents using screen time more than 2-3 h per day, and gender differences exist. Essential information was missing for quality of evidence including heterogeneity in mental health and screen time-based measures, and self-report data collection methods. The findings are of particular significance given the global public health concern of lifestyle-attributed diseases and the possibility for novel approaches to mental health. Future research should examine the psychological impact of reducing time spent using screens for leisure among adolescents, whilst accounting for possible confounding factors such as physical activity and dietary behaviours. It is critical that the reciprocal relationship between lifestyle behaviours and mental health is represented in both the psychiatric and public health forum.
A Self-Regulation Theory-Based Asthma Management Mobile App for Adolescents: A Usability Assessment.
Sage, Adam; Roberts, Courtney; Geryk, Lorie; Sleath, Betsy; Tate, Deborah; Carpenter, Delesha
2017-02-01
Self-regulation theory suggests people learn to influence their own behavior through self-monitoring, goal-setting, feedback, self-reward, and self-instruction, all of which smartphones are now capable of facilitating. Several mobile apps exist to manage asthma; however, little evidence exists about whether these apps employ user-centered design processes that adhere to government usability guidelines for mobile apps. Building upon a previous study that documented adolescent preferences for an asthma self-management app, we employed a user-centered approach to assess the usability of a high-fidelity wireframe for an asthma self-management app intended for use by adolescents with persistent asthma. Individual interviews were conducted with adolescents (ages 11-18 years) with persistent asthma who owned a smartphone (N=8). Adolescents were asked to evaluate a PDF app wireframe consisting of 76 screen shots displaying app features, including log in and home screen, profile setup, settings and info, self-management features, and graphical displays for charting asthma control and medication. Preferences, comments, and suggestions for each set of screen shots were assessed using the audio-recorded interviews. Two coders reached consensus on adolescent evaluations of the following aspects of app features: (1) usability, (2) behavioral intentions to use, (3) confusing aspects, and (4) suggestions for improvement. The app wireframe was generally well received, and several suggestions for improvement were recorded. Suggestions included increased customization of charts and notifications, reminders, and alerts. Participants preferred longitudinal data about asthma control and medication use to be displayed using line graphs. All participants reported that they would find an asthma management app like the one depicted in the wireframe useful for managing their asthma. Early stage usability tests guided by government usability guidelines (usability.gov) revealed areas for improvement for an asthma self-management app for adolescents. Addressing these areas will be critical to developing an engaging and effective asthma self-management app that is capable of improving adolescent asthma outcomes. ©Adam Sage, Courtney Roberts, Lorie Geryk, Betsy Sleath, Deborah Tate, Delesha Carpenter. Originally published in JMIR Human Factors (http://humanfactors.jmir.org), 01.02.2017.
Nelson, Nathaniel W; Anderson, Carolyn R; Thuras, Paul; Kehle-Forbes, Shannon M; Arbisi, Paul A; Erbes, Christopher R; Polusny, Melissa A
2015-03-01
Estimates of the prevalence of mild traumatic brain injury (mTBI) among military personnel and combat veterans rely almost exclusively on retrospective self-reports; however, reliability of these reports has received little attention. To examine the consistency of reporting of mTBI over time and identify factors associated with inconsistent reporting. A longitudinal cohort of 948 US National Guard Soldiers deployed to Iraq completed self-report questionnaire screening for mTBI and psychological symptoms while in-theatre 1 month before returning home (time 1, T1) and 1 year later (time 2, T2). Most respondents (n = 811, 85.5%) were consistent in their reporting of mTBI across time. Among those who were inconsistent in their reports (n = 137, 14.5%), the majority denied mTBI at T1 and affirmed mTBI at T2 (n = 123, 89.8%). Respondents rarely endorsed mTBI in-theatre and later denied mTBI (n = 14, 10.2% of those with inconsistent reports). Post-deployment post-traumatic stress symptoms and non-specific physical complaints were significantly associated with inconsistent report of mTBI. Military service members' self-reports of mTBI are generally consistent over time; however, inconsistency in retrospective self-reporting of mTBI status is associated with current post-traumatic stress symptoms and non-specific physical health complaints. Royal College of Psychiatrists.
Sedentary behaviours among Australian adolescents.
Hardy, Louise L; Dobbins, Timothy; Booth, Michael L; Denney-Wilson, Elizabeth; Okely, Anthony D
2006-12-01
To describe the prevalence and distribution (by demographic characteristics and body mass index [BMI] category) of sedentary behaviour among Australian adolescents aged 11-15 years. Cross-sectional representative population survey of school students (n = 2,750) in New South Wales, conducted in 2004. Students' self-reported time spent during a usual week in five categories of sedentary behaviour (small screen recreation [SSR], education, cultural, social and non-active travel). Height and weight were measured. Grade 6, 8 and 10 students spent approximately 34 hours, 41 hours and 45 hours/week of their discretionary time, respectively, engaged in sedentary behaviour. Urban students and students from Asian-speaking backgrounds spent significantly more time sedentary than students from rural areas or other cultural backgrounds. SSR accounted for 60% and 54% of sedentary behaviour among primary and high school students, respectively. Overweight and obese students spent more time in SSR than healthy weight students. Out-of-school hours educational activities accounted for approximately 20% of sedentary behaviour and increased with age. Girls spent twice the time in social activities compared with boys. Time spent in cultural activities declined with age. Sedentary behaviours among young people differ according to sex, age and cultural background. At least half of all time spent in sedentary behaviours was spent engaged in SSR. BMI was significantly associated with sedentary behaviour among some children, but not consistently across age groups. A clear understanding of young people's patterns of sedentary behaviour is required to develop effective and sustainable intervention programs to promote healthy living.
Derivation of the density functional theory from the cluster expansion.
Hsu, J Y
2003-09-26
The density functional theory is derived from a cluster expansion by truncating the higher-order correlations in one and only one term in the kinetic energy. The formulation allows self-consistent calculation of the exchange correlation effect without imposing additional assumptions to generalize the local density approximation. The pair correlation is described as a two-body collision of bound-state electrons, and modifies the electron- electron interaction energy as well as the kinetic energy. The theory admits excited states, and has no self-interaction energy.
NASA Astrophysics Data System (ADS)
Lee, Y.; Bescond, M.; Logoteta, D.; Cavassilas, N.; Lannoo, M.; Luisier, M.
2018-05-01
We propose an efficient method to quantum mechanically treat anharmonic interactions in the atomistic nonequilibrium Green's function simulation of phonon transport. We demonstrate that the so-called lowest-order approximation, implemented through a rescaling technique and analytically continued by means of the Padé approximants, can be used to accurately model third-order anharmonic effects. Although the paper focuses on a specific self-energy, the method is applicable to a very wide class of physical interactions. We apply this approach to the simulation of anharmonic phonon transport in realistic Si and Ge nanowires with uniform or discontinuous cross sections. The effect of increasing the temperature above 300 K is also investigated. In all the considered cases, we are able to obtain a good agreement with the routinely adopted self-consistent Born approximation, at a remarkably lower computational cost. In the more complicated case of high temperatures (≫300 K), we find that the first-order Richardson extrapolation applied to the sequence of the Padé approximants N -1 /N results in a significant acceleration of the convergence.
Accurate quasiparticle calculation of x-ray photoelectron spectra of solids
NASA Astrophysics Data System (ADS)
Aoki, Tsubasa; Ohno, Kaoru
2018-05-01
It has been highly desired to provide an accurate and reliable method to calculate core electron binding energies (CEBEs) of crystals and to understand the final state screening effect on a core hole in high resolution x-ray photoelectron spectroscopy (XPS), because the ΔSCF method cannot be simply used for bulk systems. We propose to use the quasiparticle calculation based on many-body perturbation theory for this problem. In this study, CEBEs of band-gapped crystals, silicon, diamond, β-SiC, BN, and AlP, are investigated by means of the GW approximation (GWA) using the full ω integration and compared with the preexisting XPS data. The screening effect on a deep core hole is also investigated in detail by evaluating the relaxation energy (RE) from the core and valence contributions separately. Calculated results show that not only the valence electrons but also the core electrons have an important contribution to the RE, and the GWA have a tendency to underestimate CEBEs due to the excess RE. This underestimation can be improved by introducing the self-screening correction to the GWA. The resulting C1s, B1s, N1s, Si2p, and Al2p CEBEs are in excellent agreement with the experiments within 1 eV absolute error range. The present self-screening corrected GW approach has the capability to achieve the highly accurate prediction of CEBEs without any empirical parameter for band-gapped crystals, and provide a more reliable theoretical approach than the conventional ΔSCF-DFT method.
Accurate quasiparticle calculation of x-ray photoelectron spectra of solids.
Aoki, Tsubasa; Ohno, Kaoru
2018-05-31
It has been highly desired to provide an accurate and reliable method to calculate core electron binding energies (CEBEs) of crystals and to understand the final state screening effect on a core hole in high resolution x-ray photoelectron spectroscopy (XPS), because the ΔSCF method cannot be simply used for bulk systems. We propose to use the quasiparticle calculation based on many-body perturbation theory for this problem. In this study, CEBEs of band-gapped crystals, silicon, diamond, β-SiC, BN, and AlP, are investigated by means of the GW approximation (GWA) using the full ω integration and compared with the preexisting XPS data. The screening effect on a deep core hole is also investigated in detail by evaluating the relaxation energy (RE) from the core and valence contributions separately. Calculated results show that not only the valence electrons but also the core electrons have an important contribution to the RE, and the GWA have a tendency to underestimate CEBEs due to the excess RE. This underestimation can be improved by introducing the self-screening correction to the GWA. The resulting C1s, B1s, N1s, Si2p, and Al2p CEBEs are in excellent agreement with the experiments within 1 eV absolute error range. The present self-screening corrected GW approach has the capability to achieve the highly accurate prediction of CEBEs without any empirical parameter for band-gapped crystals, and provide a more reliable theoretical approach than the conventional ΔSCF-DFT method.
Wu, Sangwook
2009-03-01
We investigate dynamical self-arrest in a diblock copolymer melt using a replica approach within a self-consistent local method based on dynamical mean-field theory (DMFT). The local replica approach effectively predicts (chiN)_{A} for dynamical self-arrest in a block copolymer melt for symmetric and asymmetric cases. We discuss the competition of the cubic and quartic interactions in the Landau free energy for a block copolymer melt in stabilizing a glassy state depending on the chain length. Our local replica theory provides a universal value for the dynamical self-arrest in block copolymer melts with (chiN)_{A} approximately 10.5+64N;{-3/10} for the symmetric case.
Use of the self-organizing feature map to diagnose abnormal engineering change
NASA Astrophysics Data System (ADS)
Lu, Ruei-Shan; Wu, Zhi-Ting; Peng, Kuo-Wei; Yu, Tai-Yi
2015-07-01
This study established identification manners with self-organizing feature map (SOM) to achieve the goal of monitoring Engineering Change (EC) based on historical data of a company that specializes in computers and peripherals. The product life cycle of this company is 3-6 months. The historical data were divided into three parts, each covering four months. The first part, comprising 2,343 records from January to April (the training period), comprise the Control Group. The second and third parts comprise Experimental Groups (EG) 1 and 2, respectively. For EG 1 and 2, the successful rate of recognizing information on abnormal ECs was approximately 96% and 95%, respectively. This paper shows the importance and screening procedures of abnormal engineering change for a particular company specializing in computers and peripherals.
ERIC Educational Resources Information Center
Sagirli, Muhittin; Okur, Burçin
2017-01-01
The aim of this study was to analyse perceptions of fourth grade primary school students on their reading ability. In study, screening model was used as a quantitative research method. The sample of this research was selected by convenience sampling. The sample consisted of 556 fourth grade students who received education in 8 public schools in…
ERIC Educational Resources Information Center
Duncombe, Melissa E.; Havighurst, Sophie S.; Holland, Kerry A.; Frankling, Emma J.
2012-01-01
The goal of this study was to examine the impact of different parenting characteristics on child disruptive behavior and emotional regulation among a sample of at-risk children. The sample consisted of 373 Australian 5- to 9-year-old children who were screened for serious behavior problems. Seven parenting variables based on self-report were…
Fargnoli, Vanessa; Petignat, Patrick; Burton-Jeangros, Claudine
2015-01-01
Objectives Human papillomavirus self-sampling (self-HPV) is regarded as an alternative to Pap smear testing for women who do not participate in cervical cancer screening. This qualitative study aimed to determine women’s views on cervical cancer screening and the various obstacles to participation in screening, and to evaluate the perceived benefits and disadvantages of self-HPV. Method Twenty-four focus groups were conducted in 2012, with a total of 125 participants aged between 24 and 67 years. They were recruited through different channels, including flyers and posters, personal contacts, and an ongoing clinical trial focused on the unscreened population. Interview transcripts have been coded with the ATLAS.ti CAQDAS. Results Fifty-seven participants regularly attended screening and 68 had not been screened in the past 3 years. While some participants considered self-HPV as an acceptable screening method, others expressed concerns. Benefits included access, reduced costs, and time-saving. Disadvantages included the fear of not performing the test correctly, hurting oneself, and the accuracy of the test. Participants expressed concern that self-HPV would replace gynecological visits. Conclusion Self-HPV is not likely to rapidly or substantially modify women’s behaviors in regard to screening. While it may offer benefits in some specific situations, most women emphasized the advantages of regular gynecologist visits. PMID:26604830
Seay, Julia; Ranck, Atticus; Weiss, Roy; Salgado, Christopher; Fein, Lydia; Kobetz, Erin
2017-08-01
Transgender men are less likely than cisgender women to receive cervical cancer screening. The purpose of the current study was to understand experiences with and preferences for cervical cancer screening among transgender men. Ninety-one transgender men ages 21-63 completed the survey. The survey evaluated experiences with and preferences for screening, including opinions regarding human papillomavirus (HPV) self-sampling as a primary cervical cancer screening. Half (50.5%) of participants did not have Pap smear screening within the past 3 years. The majority (57.1%) of participants preferred HPV self-sampling over provider-collected Pap smear screening. Participants who reported discrimination were more likely to prefer HPV self-sampling (odds ratio = 3.29, 95% confidence interval 1.38-7.84, P = 0.007). Primary HPV testing via HPV self-sampling may improve cervical cancer screening uptake among transgender men. Future work should pilot this innovative cervical cancer screening method within this population.
Church, A. Timothy; Katigbak, Marcia S.; Reyes, Jose Alberto S.; Salanga, Maria Guadalupe C.; Miramontes, Lilia A.; Adams, Nerissa B.
2008-01-01
Trait and cultural psychology perspectives on the cross-situational consistency of behavior, and the predictive validity of traits, were tested in a daily process study in the United States (N = 68), an individualistic culture, and the Philippines (N = 80), a collectivistic culture. Participants completed the Revised NEO Personality Inventory (Costa & McCrae, 1992) and a measure of self-monitoring, then reported their daily behaviors and associated situational contexts for approximately 30 days. Consistent with trait perspectives, the Big Five traits predicted daily behaviors in both cultures, and relative (interindividual) consistency was observed across many, although not all, situational contexts. The frequency of various Big Five behaviors varied across relevant situational contexts in both cultures and, consistent with cultural psychology perspectives, there was a tendency for Filipinos to exhibit greater situational variability than Americans. Self-monitoring showed some ability to account for individual differences in situational variability in the American sample, but not the Filipino sample. PMID:22146866
Balasubramanian, Akhila; Kulasingam, Shalini L.; Baer, Atar; Hughes, James P.; Myers, Evan R.; Mao, Constance; Kiviat, Nancy B.; Koutsky, Laura A.
2010-01-01
Objective Estimate the accuracy and cost-effectiveness of cervical cancer screening strategies based on high-risk HPV DNA testing of self-collected vaginal samples. Materials and Methods A subset of 1,665 women (18-50 years of age) participating in a cervical cancer screening study were screened by liquid-based cytology and by high-risk HPV DNA testing of both self-collected vaginal swab samples and clinician-collected cervical samples. Women with positive/abnormal screening test results and a subset of women with negative screening test results were triaged to colposcopy. Based on individual and combined test results, five screening strategies were defined. Estimates of sensitivity and specificity for cervical intraepithelial neoplasia grade 2 or worse were calculated and a Markov model was used to estimate the incremental cost-effectiveness ratios (ICERs) for each strategy. Results Compared to cytology-based screening, high-risk HPV DNA testing of self-collected vaginal samples was more sensitive (68%, 95%CI=58%-78% versus 85%, 95%CI=76%-94%) but less specific (89%, 95%CI=86%-91% versus 73%, 95%CI=67%-79%). A strategy of high-risk HPV DNA testing of self-collected vaginal samples followed by cytology triage of HPV positive women, was comparably sensitive (75%, 95%CI=64%-86%) and specific (88%, 95%CI=85%-92%) to cytology-based screening. In-home self-collection for high-risk HPV DNA detection followed by in-clinic cytology triage had a slightly lower lifetime cost and a slightly higher quality-adjusted life expectancy than did cytology-based screening (ICER of triennial screening compared to no screening was $9,871/QALY and $12,878/QALY, respectively). Conclusions Triennial screening by high-risk HPV DNA testing of in-home, self-collected vaginal samples followed by in-clinic cytology triage was cost-effective. PMID:20592553
Turbulent MHD transport coefficients - An attempt at self-consistency
NASA Technical Reports Server (NTRS)
Chen, H.; Montgomery, D.
1987-01-01
In this paper, some multiple scale perturbation calculations of turbulent MHD transport coefficients begun in earlier papers are first completed. These generalize 'alpha effect' calculations by treating the velocity field and magnetic field on the same footing. Then the problem of rendering such calculations self-consistent is addressed, generalizing an eddy-viscosity hypothesis similar to that of Heisenberg for the Navier-Stokes case. The method also borrows from Kraichnan's direct interaction approximation. The output is a set of integral equations relating the spectra and the turbulent transport coefficients. Previous 'alpha effect' and 'beta effect' coefficients emerge as limiting cases. A treatment of the inertial range can also be given, consistent with a -5/3 energy spectrum power law. In the Navier-Stokes limit, a value of 1.72 is extracted for the Kolmogorov constant. Further applications to MHD are possible.
DFTB3: Extension of the self-consistent-charge density-functional tight-binding method (SCC-DFTB).
Gaus, Michael; Cui, Qiang; Elstner, Marcus
2012-04-10
The self-consistent-charge density-functional tight-binding method (SCC-DFTB) is an approximate quantum chemical method derived from density functional theory (DFT) based on a second-order expansion of the DFT total energy around a reference density. In the present study we combine earlier extensions and improve them consistently with, first, an improved Coulomb interaction between atomic partial charges, and second, the complete third-order expansion of the DFT total energy. These modifications lead us to the next generation of the DFTB methodology called DFTB3, which substantially improves the description of charged systems containing elements C, H, N, O, and P, especially regarding hydrogen binding energies and proton affinities. As a result, DFTB3 is particularly applicable to biomolecular systems. Remaining challenges and possible solutions are also briefly discussed.
The Lick-Gaertner automatic measuring system
NASA Technical Reports Server (NTRS)
Vasilevskis, S.; Popov, W. A.
1971-01-01
The Lick-Gaertner automatic equipment has been designed mainly for the measurement of stellar proper motions with reference to galaxies, and consists of two main components: the survey machine and the automatic measuring engine. The survey machine is used for initial inspection and selection of objects for subsequent measurement. Two plates, up to 17 x 17 inches each, are surveyed simultaneously by means of projection on a screen. The approximate positions of objects selected are measured by two optical screws: helical lines cut through an aluminum coating on glass cylinders. These approximate coordinates to a precision of the order of 0.03mm are transmitted to a card punch by encoders connected with the cylinders.
Breast cancer screening practices among first-generation immigrant muslim women.
Hasnain, Memoona; Menon, Usha; Ferrans, Carol Estwing; Szalacha, Laura
2014-07-01
The purpose of this study was to identify beliefs about breast cancer, screening practices, and factors associated with mammography use among first-generation immigrant Muslim women in Chicago, IL. A convenience sample of 207 first-generation immigrant Muslim women (Middle Eastern 51%; South Asian 49%) completed a culturally adapted questionnaire developed from established instruments. The questionnaire was administered in Urdu, Hindi, Arabic, or English, based on participant preference. Internal-consistency reliability was demonstrated for all scales (alpha coefficients ranged from 0.64 to 0.91). Associations between enabling, predisposing, and need variables and the primary outcome of mammography use were explored by fitting logistic regression models. Although 70% of the women reported having had a mammogram at least once, only 52% had had one within the past 2 years. Four factors were significant predictors of ever having had a mammogram: years in the United States, self-efficacy, perceived importance of mammography, and intent to be screened. Five factors were significant predictors of adherence (having had a mammogram in the past 2 years): years in the United States, having a primary care provider, perceived importance of mammography, barriers, and intent to be screened. This article sheds light on current screening practices and identifies theory-based constructs that facilitate and hinder Muslim women's participation in mammography screening. Our findings provide insights for reaching out particularly to new immigrants, developing patient education programs grounded in culturally appropriate approaches to address perceived barriers and building women's self-efficacy, as well as systems-level considerations for ensuring access to primary care providers.
Self-Report Versus Medical Record for Mammography Screening Among Minority Women.
Nandy, Karabi; Menon, Usha; Szalacha, Laura A; Park, HanJong; Lee, Jongwon; Lee, Eunice E
2016-12-01
Self-report is the most common means of obtaining mammography screening data. The purpose of this study was to assess the accuracy of minority women's self-reported mammography by comparing their self-reported dates of mammograms with those in their medical records from a community-based randomized control trial. We found that out of 192 women, 116 signed the Health Information Portability and Accountability Act form and, among these, 97 had medical records that could be verified (97 / 116 = 83.6%). Ninety-two records matched where both sources confirmed a mammogram; 48 of 92 (52.2%) matched perfectly on self-reported date of mammogram. Complexities in the verification process warrant caution when verifying self-reported mammography screening in minority populations. In spite of some limitations, our findings support the usage of self-reported data on mammography as a validated tool for other researchers investigating mammography screening among minority women who continue to have low screening rates. © The Author(s) 2016.
On the Debye-Hückel effect of electric screening
NASA Astrophysics Data System (ADS)
Campos, L. M. B. C.; Lau, F. J. P.
2014-07-01
The paper considers non-linear self-consistent electric potential equation (Sec. I), due to a cloud made of a single species of electric charges, satisfying a Boltzmann distribution law (Sec. II). Exact solutions are obtained in a simple logarithmic form, in three cases: (Sec. III) spherical radial symmetry; (Sec. IV) plane parallel symmetry; (Sec. V) a special case of azimuthal-cylindrical symmetry. All these solutions, and their transformations (Sec. VI), involve the Debye-Hückel radius; the latter was originally defined from a solution of the linearized self-consistent potential equation. Using an exact solution of the self-consistent potential equation, the distance at which the potential vanishes differs from the Debye-Hückel radius by a factor of √2 . The preceding (Secs. II-VI) simple logarithmic exact solutions of the self-consistent potential equations involve no arbitrary constants, and thus are special or singular integrals not the general integral. The general solution of the self-consistent potential equation is obtained in the plane parallel case (Sec. VII), and it involves two arbitrary constants that can be reduced to one via a translation (Sec. VIII). The plots of dimensionless potential (Figure 1), electric field (Figure 2), charge density (Figure 3), and total charge between ζ and infinity (Figure 4), versus distance normalized to Debye-Hückel radius ζ ≡ z/a, show that (Sec. IX) there is a continuum of solutions, ranging from a charge distribution concentrated inside the Debye-Hückel radius to one spread-out beyond it. The latter case leads to the limiting case of logarithmic potential, and stronger electric field; the former case, of very concentrated charge distribution, leads to a fratricide effect and weaker electric field.
On the Debye–Hückel effect of electric screening
DOE Office of Scientific and Technical Information (OSTI.GOV)
Campos, L. M. B. C.; Lau, F. J. P.
2014-07-15
The paper considers non-linear self-consistent electric potential equation (Sec. I), due to a cloud made of a single species of electric charges, satisfying a Boltzmann distribution law (Sec. II). Exact solutions are obtained in a simple logarithmic form, in three cases: (Sec. III) spherical radial symmetry; (Sec. IV) plane parallel symmetry; (Sec. V) a special case of azimuthal-cylindrical symmetry. All these solutions, and their transformations (Sec. VI), involve the Debye-Hückel radius; the latter was originally defined from a solution of the linearized self-consistent potential equation. Using an exact solution of the self-consistent potential equation, the distance at which the potentialmore » vanishes differs from the Debye-Hückel radius by a factor of √(2). The preceding (Secs. II–VI) simple logarithmic exact solutions of the self-consistent potential equations involve no arbitrary constants, and thus are special or singular integrals not the general integral. The general solution of the self-consistent potential equation is obtained in the plane parallel case (Sec. VII), and it involves two arbitrary constants that can be reduced to one via a translation (Sec. VIII). The plots of dimensionless potential (Figure 1), electric field (Figure 2), charge density (Figure 3), and total charge between ζ and infinity (Figure 4), versus distance normalized to Debye-Hückel radius ζ ≡ z/a, show that (Sec. IX) there is a continuum of solutions, ranging from a charge distribution concentrated inside the Debye-Hückel radius to one spread-out beyond it. The latter case leads to the limiting case of logarithmic potential, and stronger electric field; the former case, of very concentrated charge distribution, leads to a fratricide effect and weaker electric field.« less
Brodey, Benjamin; Purcell, Susan E; Rhea, Karen; Maier, Philip; First, Michael; Zweede, Lisa; Sinisterra, Manuela; Nunn, M Brad; Austin, Marie-Paule; Brodey, Inger S
2018-03-23
The Structured Clinical Interview for DSM (SCID) is considered the gold standard assessment for accurate, reliable psychiatric diagnoses; however, because of its length, complexity, and training required, the SCID is rarely used outside of research. This paper aims to describe the development and initial validation of a Web-based, self-report screening instrument (the Screening Assessment for Guiding Evaluation-Self-Report, SAGE-SR) based on the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) and the SCID-5-Clinician Version (CV) intended to make accurate, broad-based behavioral health diagnostic screening more accessible within clinical care. First, study staff drafted approximately 1200 self-report items representing individual granular symptoms in the diagnostic criteria for the 8 primary SCID-CV modules. An expert panel iteratively reviewed, critiqued, and revised items. The resulting items were iteratively administered and revised through 3 rounds of cognitive interviewing with community mental health center participants. In the first 2 rounds, the SCID was also administered to participants to directly compare their Likert self-report and SCID responses. A second expert panel evaluated the final pool of items from cognitive interviewing and criteria in the DSM-5 to construct the SAGE-SR, a computerized adaptive instrument that uses branching logic from a screener section to administer appropriate follow-up questions to refine the differential diagnoses. The SAGE-SR was administered to healthy controls and outpatient mental health clinic clients to assess test duration and test-retest reliability. Cutoff scores for screening into follow-up diagnostic sections and criteria for inclusion of diagnoses in the differential diagnosis were evaluated. The expert panel reduced the initial 1200 test items to 664 items that panel members agreed collectively represented the SCID items from the 8 targeted modules and DSM criteria for the covered diagnoses. These 664 items were iteratively submitted to 3 rounds of cognitive interviewing with 50 community mental health center participants; the expert panel reviewed session summaries and agreed on a final set of 661 clear and concise self-report items representing the desired criteria in the DSM-5. The SAGE-SR constructed from this item pool took an average of 14 min to complete in a nonclinical sample versus 24 min in a clinical sample. Responses to individual items can be combined to generate DSM criteria endorsements and differential diagnoses, as well as provide indices of individual symptom severity. Preliminary measures of test-retest reliability in a small, nonclinical sample were promising, with good to excellent reliability for screener items in 11 of 13 diagnostic screening modules (intraclass correlation coefficient [ICC] or kappa coefficients ranging from .60 to .90), with mania achieving fair test-retest reliability (ICC=.50) and other substance use endorsed too infrequently for analysis. The SAGE-SR is a computerized adaptive self-report instrument designed to provide rigorous differential diagnostic information to clinicians. ©Benjamin Brodey, Susan E Purcell, Karen Rhea, Philip Maier, Michael First, Lisa Zweede, Manuela Sinisterra, M Brad Nunn, Marie-Paule Austin, Inger S Brodey. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 23.03.2018.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mehmood, Faisal; General Dynamics Information Technology, Inc., Dayton, Ohio 45433; Pachter, Ruth, E-mail: ruth.pachter@us.af.mil
Prediction of the frequency-dependent dielectric function of thin films poses computational challenges, and at the same time experimental characterization by spectroscopic ellipsometry remains difficult to interpret because of changes in stoichiometry and surface morphology, temperature, thickness of the film, or substrate. In this work, we report calculations for titanium nitride (TiN), a promising material for plasmonic applications because of less loss and other practical advantages compared to noble metals. We investigated structural, electronic, and optical properties of stoichiometric bulk TiN, as well as of the TiN(100), TiN(110), and TiN(111) outermost surfaces. Density functional theory (DFT) and many-body GW methods (Green'smore » (G) function-based approximation with screened Coulomb interaction (W)) were used, ranging from G{sub 0}W{sub 0}, GW{sub 0} to partially self-consistent sc-GW{sub 0}, as well as the GW-BSE (Bethe-Salpeter equation) and time-dependent DFT (TDDFT) methods for prediction of the optical properties. Structural parameters and the band structure for bulk TiN were shown to be consistent with previous work. Calculated dielectric functions, plasma frequencies, reflectivity, and the electron energy loss spectrum demonstrated consistency with experiment at the GW{sub 0}-BSE level. Deviations from experimental data are expected due to varying experimental conditions. Comparison of our results to spectroscopic ellipsometry data for realistic nanostructures has shown that although TDDFT may provide a computationally feasible level of theory in evaluation of the dielectric function, application is subject to validation with GW-BSE calculations.« less
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-23
... experiences with listed company peers; trading information and market data; and a series of institutional... approximately $20,000 annually, provide stock pricing data, news, institutional ownership information, research... criteria for satisfying the tiers are transparent and quantitative, and they are applied consistently to...
Clustering and correlates of screen-time and eating behaviours among young adolescents.
Pearson, Natalie; Griffiths, Paula; Biddle, Stuart Jh; Johnston, Julie P; McGeorge, Sonia; Haycraft, Emma
2017-05-31
Screen-time and eating behaviours are associated in adolescents, but few studies have examined the clustering of these health behaviours in this age group. The identification of clustered health behaviours, and influences on adolescents' clustered health behaviours, at the time when they are most likely to become habitual, is important for intervention design. The purpose of this study was to assess the prevalence and clustering of health behaviours in adolescents, and examine the sociodemographic, individual, behavioural, and home social and physical environmental correlates of clustered health behaviours. Adolescents aged 11-12 years (n = 527, 48% boys) completed a questionnaire during class-time which assessed screen-time (ST), fruit and vegetable (FV), and energy-dense (ED) snack consumption using a Food Frequency Questionnaire. Health behaviours were categorised into high and low frequencies based on recommendations for FV and ST and median splits for ED snacks. Adolescents reported on their habits, self-efficacy, eating at the television (TV), eating and watching TV together with parents, restrictive parenting practices, and the availability and accessibility of foods within the home. Behavioural clustering was assessed using an observed over expected ratio (O/E). Correlates of clustered behaviours were examined using multivariate multinomial logistic regression. Approximately 70% reported having two or three health risk behaviours. Overall, O/E ratios were close to 1, which indicates clustering. The three risk behaviour combination of low FV, high ED, and high ST occurred more frequently than expected (O/E ratio = 1.06 95% CI 1.01, 1.15. Individual, behavioural, and social and physical home environmental correlates were differentially associated with behavioural clusters. Correlates consistently associated with clusters included eating ED snacks while watching TV, eating at the TV with parents, and the availability and accessibility of ED snack foods within the home. There is a high prevalence of screen time and unhealthy eating, and screen time is coupled with unhealthy dietary behaviours. Strategies and policies are required that simultaneously address reductions in screen time and changes to habitual dietary patterns, such as TV snacking and snack availability and accessibility. These may require a combination of individual, social and environmental changes alongside conscious and more automatic (nudging) strategies.
Rasheed, Tabish; Ahmad, Shabbir
2010-10-01
Ab initio Hartree-Fock (HF), density functional theory (DFT) and second-order Møller-Plesset (MP2) methods were used to perform harmonic and anharmonic calculations for the biomolecule cytosine and its deuterated derivative. The anharmonic vibrational spectra were computed using the vibrational self-consistent field (VSCF) and correlation-corrected vibrational self-consistent field (CC-VSCF) methods. Calculated anharmonic frequencies have been compared with the argon matrix spectra reported in literature. The results were analyzed with focus on the properties of anharmonic couplings between pair of modes. A simple and easy to use formula for calculation of mode-mode coupling magnitudes has been derived. The key element in present approach is the approximation that only interactions between pairs of normal modes have been taken into account, while interactions of triples or more are neglected. FTIR and Raman spectra of solid state cytosine have been recorded in the regions 400-4000 cm(-1) and 60-4000 cm(-1), respectively. Vibrational analysis and assignments are based on calculated potential energy distribution (PED) values. Copyright 2010 Elsevier B.V. All rights reserved.
Self-Consistent Field Theory of Gaussian Ring Polymers
NASA Astrophysics Data System (ADS)
Kim, Jaeup; Yang, Yong-Biao; Lee, Won Bo
2012-02-01
Ring polymers, being free from chain ends, have fundamental importance in understanding the polymer statics and dynamics which are strongly influenced by the chain end effects. At a glance, their theoretical treatment may not seem particularly difficult, but the absence of chain ends and the topological constraints make the problem non-trivial, which results in limited success in the analytical or semi-analytical formulation of ring polymer theory. Here, I present a self-consistent field theory (SCFT) formalism of Gaussian (topologically unconstrained) ring polymers for the first time. The resulting static property of homogeneous and inhomogeneous ring polymers are compared with the random phase approximation (RPA) results. The critical point for ring homopolymer system is exactly the same as the linear polymer case, χN = 2, since a critical point does not depend on local structures of polymers. The critical point for ring diblock copolymer melts is χN 17.795, which is approximately 1.7 times of that of linear diblock copolymer melts, χN 10.495. The difference is due to the ring structure constraint.
Jago, Russell; Wood, Lesley; Zahra, Jesmond; Thompson, Janice L; Sebire, Simon J
2015-04-01
Children's screen viewing (SV) is associated with higher levels of childhood obesity. Many children exceed the American Academy of Pediatrics guideline of 2 hours of television (TV) per day. There is limited information about how parenting styles and parental self-efficacy to limit child screen time are associated with children's SV. This study examined whether parenting styles were associated with the SV of young children and whether any effects were mediated by parental self-efficacy to limit screen time. Data were from a cross-sectional survey conducted in 2013. Child and parent SV were reported by a parent, who also provided information about their parenting practices and self-efficacy to restrict SV. A four-step regression method examined whether parenting styles were associated with the SV of young children. Mediation by parental self-efficacy to limit screen time was examined using indirect effects. On a weekday, 90% of children watched TV for <2 hours per day, decreasing to 55% for boys and 58% for girls at weekends. At the weekend, 75% of children used a personal computer at home, compared with 61% during the week. Self-reported parental control, but not nurturance, was associated with children's TV viewing. Parental self-efficacy to limit screen time was independently associated with child weekday TV viewing and mediated associations between parental control and SV. Parental control was associated with lower levels of SV among 5- to 6-year-old children. This association was partially mediated by parental self-efficacy to limit screen time. The development of strategies to increase parental self-efficacy to limit screen-time may be useful.
Wood, Lesley; Zahra, Jesmond; Thompson, Janice L.; Sebire, Simon J.
2015-01-01
Abstract Background: Children's screen viewing (SV) is associated with higher levels of childhood obesity. Many children exceed the American Academy of Pediatrics guideline of 2 hours of television (TV) per day. There is limited information about how parenting styles and parental self-efficacy to limit child screen time are associated with children's SV. This study examined whether parenting styles were associated with the SV of young children and whether any effects were mediated by parental self-efficacy to limit screen time. Methods: Data were from a cross-sectional survey conducted in 2013. Child and parent SV were reported by a parent, who also provided information about their parenting practices and self-efficacy to restrict SV. A four-step regression method examined whether parenting styles were associated with the SV of young children. Mediation by parental self-efficacy to limit screen time was examined using indirect effects. Results: On a weekday, 90% of children watched TV for <2 hours per day, decreasing to 55% for boys and 58% for girls at weekends. At the weekend, 75% of children used a personal computer at home, compared with 61% during the week. Self-reported parental control, but not nurturance, was associated with children's TV viewing. Parental self-efficacy to limit screen time was independently associated with child weekday TV viewing and mediated associations between parental control and SV. Conclusions: Parental control was associated with lower levels of SV among 5- to 6-year-old children. This association was partially mediated by parental self-efficacy to limit screen time. The development of strategies to increase parental self-efficacy to limit screen-time may be useful. PMID:25584518
2016-07-01
petroleum hydrocarbon fuels due to higher densities, lower viscosities , and increased weathering (mass depletion) of residual chlorinated solvent DNAPL...generally classified as stratified layers of fine sand and silt with few clay layers. A silt layer was penetrated consistently at a depth of about 45...e.g., stiff clays ) there is potential for the thickness of the dye interaction zone to increase to approximately 1-2 mm. Intuition suggests that this
Utilization of Routine Primary Care Services Among Dancers.
Alimena, Stephanie; Air, Mary E; Gribbin, Caitlin; Manejias, Elizabeth
2016-01-01
This study examines the current utilization of primary and preventive health care services among dancers in order to assess their self-reported primary care needs. Participants were 37 dancers from a variety of dance backgrounds who presented for a free dancer health screening in a large US metropolitan area (30 females, 7 males; mean age: 27.5 ± 7.4 years; age range: 19 to 49 years; mean years of professional dancing: 6.4 ± 5.4 years). Dancers were screened for use of primary care, mental health, and women's health resources using the Health Screen for Professional Dancers developed by the Task Force on Dancer Health. Most dancers had health insurance (62.2%), but within the last 2 years, only approximately half of them (54.1%) reported having a physical examination by a physician. Within the last year, 54.1% of dancers had had a dental check-up, and 56.7% of female dancers received gynecologic care. Thirty percent of female participants indicated irregular menstrual cycles, 16.7% had never been to a gynecologist, and 16.7% were taking birth control. Utilization of calcium and vitamin D supplementation was 27.0% and 29.7%, respectively, and 73.0% were interested in nutritional counseling. A high rate of psychological fatigue and sleep deprivation was found (35.1%), along with a concomitant high rate of self-reported need for mental health counseling (29.7%). Cigarette and recreational drug use was low (5.4% and 5.4%); however, 32.4% engaged in binge drinking within the last year (based on the CDC definition). These findings indicate that dancers infrequently access primary care services, despite high self-reported need for nutritional, mental, and menstrual health counseling and treatment. More studies are warranted to understand dancers' primary health care seeking behavior.
Dan, K; Datta, A; Yoshida, Y; Saito, G; Yoshikawa, K; Roy, M
2016-02-28
Differential Scanning Calorimetry (DSC) and optical polarization microscopy of a mixture of the liquid crystalline material (N-(4-methoxybenzylidene)-4-butylaniline, MBBA) and a Fe-based room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrachloroferrate ([Emim](+) [FeCl4](-), EMIF) indicate a decrease in the nematic-isotropic (N-I) phase transition temperature (T(NI)) with an increase in EMIF concentration, explained by a proposed model of Coulomb "screening" of MBBA quadrupoles by the EMIF ions along with ionic "self screening." DSC studies of EMIF-MBBA and pure EMIF and comparison with pure MBBA results show that the major transitions in pure EMIF have Arrhenius behaviour, but more importantly the previously found convex Arrhenius behaviour of the pristine MBBA [K. Dan et al., Europhys. Lett. 108, 36007 (2014)] becomes Arrhenius in the mixture, indicating a conversion of the entropic N-I activation barrier to an enthalpic one. In presence of EMIF, a drastic decrease in the intensity of out-of-plane distortions of benzene rings in MBBA is found from Fourier transform infrared spectroscopy, consistent with significant reduction in the conformational states of MBBA. This suppression of large amplitude motion is again consistent with a Coulomb screening and gives a molecular basis for the entropic-to-enthalpic conversion of the N-I activation barrier.
Sasaki, Ryo; Angelaki, Dora E.
2017-01-01
We use visual image motion to judge the movement of objects, as well as our own movements through the environment. Generally, image motion components caused by object motion and self-motion are confounded in the retinal image. Thus, to estimate heading, the brain would ideally marginalize out the effects of object motion (or vice versa), but little is known about how this is accomplished neurally. Behavioral studies suggest that vestibular signals play a role in dissociating object motion and self-motion, and recent computational work suggests that a linear decoder can approximate marginalization by taking advantage of diverse multisensory representations. By measuring responses of MSTd neurons in two male rhesus monkeys and by applying a recently-developed method to approximate marginalization by linear population decoding, we tested the hypothesis that vestibular signals help to dissociate self-motion and object motion. We show that vestibular signals stabilize tuning for heading in neurons with congruent visual and vestibular heading preferences, whereas they stabilize tuning for object motion in neurons with discrepant preferences. Thus, vestibular signals enhance the separability of joint tuning for object motion and self-motion. We further show that a linear decoder, designed to approximate marginalization, allows the population to represent either self-motion or object motion with good accuracy. Decoder weights are broadly consistent with a readout strategy, suggested by recent computational work, in which responses are decoded according to the vestibular preferences of multisensory neurons. These results demonstrate, at both single neuron and population levels, that vestibular signals help to dissociate self-motion and object motion. SIGNIFICANCE STATEMENT The brain often needs to estimate one property of a changing environment while ignoring others. This can be difficult because multiple properties of the environment may be confounded in sensory signals. The brain can solve this problem by marginalizing over irrelevant properties to estimate the property-of-interest. We explore this problem in the context of self-motion and object motion, which are inherently confounded in the retinal image. We examine how diversity in a population of multisensory neurons may be exploited to decode self-motion and object motion from the population activity of neurons in macaque area MSTd. PMID:29030435
Meriggiola, M Cristina; Cerpolini, S; Bremner, W J; Mbizvo, M T; Vogelsong, K M; Martorana, G; Pelusi, G
2006-08-01
We assessed attitudes towards and acceptability of male hormonal contraception among volunteers participating in a clinical trial of a prototype regimen, consisting of progestin and testosterone injections. After completing screening, eligible men were randomly assigned to the no-treatment group (n = 40) or to receive injections of norethisterone enanthate and testosterone undecanoate or placebo at different intervals (n = 50) according to a blocked randomization list. They underwent self-administered questionnaires. The average age of the participants was approximately 28 years; most were involved in a stable relationship and had no children. Ninety-two percentage of the respondents thought that men and women should share responsibility for contraception and 75% said they would try a hormonal contraceptive if available. At the end of the treatment phase, 66% of the participants said that they would use such a method, and most rated its acceptability very highly; none reported it to be unacceptable. The injections themselves were indicated as the biggest disadvantage. No significant changes in sexual function or mood states were detected among the men who underwent hormone injections. The contraceptive tested in this study was well accepted by the participants over the course of 1 year.
Optimized Hypernetted-Chain Solutions for Helium -4 Surfaces and Metal Surfaces
NASA Astrophysics Data System (ADS)
Qian, Guo-Xin
This thesis is a study of inhomogeneous Bose systems such as liquid ('4)He slabs and inhomogeneous Fermi systems such as the electron gas in metal films, at zero temperature. Using a Jastrow-type many-body wavefunction, the ground state energy is expressed by means of Bogoliubov-Born-Green-Kirkwood -Yvon and Hypernetted-Chain techniques. For Bose systems, Euler-Lagrange equations are derived for the one- and two -body functions and systematic approximation methods are physically motivated. It is shown that the optimized variational method includes a self-consistent summation of ladder- and ring-diagrams of conventional many-body theory. For Fermi systems, a linear potential model is adopted to generate the optimized Hartree-Fock basis. Euler-Lagrange equations are derived for the two-body correlations which serve to screen the strong bare Coulomb interaction. The optimization of the pair correlation leads to an expression of correlation energy in which the state averaged RPA part is separated. Numerical applications are presented for the density profile and pair distribution function for both ('4)He surfaces and metal surfaces. Both the bulk and surface energies are calculated in good agreement with experiments.
Engel, Maike; Lincoln, Tania Marie
2016-02-01
Validated self-report instruments could provide a time efficient screening method for negative symptoms in people with schizophrenia. The aim of this study was to examine the psychometric properties of a German version of the Motivation and Pleasure Scale-Self-Report (MAP-SR) which is based on the Clinical Assessment Interview for Negative Symptoms (CAINS). In- and outpatients (N=50) with schizophrenia or schizoaffective disorder were assessed with standardized interviews and questionnaires on negative and positive symptoms and general psychopathology in schizophrenia, depression, and global functioning. The German version of the MAP-SR showed high internal consistency. Convergent validity was supported by significant correlations between the MAP-SR with the experience sub-scale of the CAINS and the negative symptom sub-scale of the Positive and Negative Syndrome Scale. The MAP-SR also exhibited discriminant validity indicated by its non-significant correlations with positive symptoms and general psychopathology, which is in line with the findings for the original version of the MAP-SR. However, the MAP-SR correlated moderately with depression. The German MAP-SR appears to be a valid and suitable diagnostic tool for the identification of negative symptoms in schizophrenia. Copyright © 2015 Elsevier Inc. All rights reserved.
Dummer, Benjamin; Wieland, Stefan; Lindner, Benjamin
2014-01-01
A major source of random variability in cortical networks is the quasi-random arrival of presynaptic action potentials from many other cells. In network studies as well as in the study of the response properties of single cells embedded in a network, synaptic background input is often approximated by Poissonian spike trains. However, the output statistics of the cells is in most cases far from being Poisson. This is inconsistent with the assumption of similar spike-train statistics for pre- and postsynaptic cells in a recurrent network. Here we tackle this problem for the popular class of integrate-and-fire neurons and study a self-consistent statistics of input and output spectra of neural spike trains. Instead of actually using a large network, we use an iterative scheme, in which we simulate a single neuron over several generations. In each of these generations, the neuron is stimulated with surrogate stochastic input that has a similar statistics as the output of the previous generation. For the surrogate input, we employ two distinct approximations: (i) a superposition of renewal spike trains with the same interspike interval density as observed in the previous generation and (ii) a Gaussian current with a power spectrum proportional to that observed in the previous generation. For input parameters that correspond to balanced input in the network, both the renewal and the Gaussian iteration procedure converge quickly and yield comparable results for the self-consistent spike-train power spectrum. We compare our results to large-scale simulations of a random sparsely connected network of leaky integrate-and-fire neurons (Brunel, 2000) and show that in the asynchronous regime close to a state of balanced synaptic input from the network, our iterative schemes provide an excellent approximations to the autocorrelation of spike trains in the recurrent network.
Virtanen, Anni; Nieminen, Pekka; Malila, Nea; Luostarinen, Tapio; Anttila, Ahti
2013-01-01
Participation rate in the national cervical cancer screening programme is currently less than 70% in Finland. A new potential method of increasing the attendance are self-taken samples for hrHPV-testing. All cervical cancer screening non-attendees in 22 municipalities received first a reminder letter. Non-attendees after the reminder letter were offered a self-sampling device. Reminder letters increased total participation from 72.6% to 79.9%, and self-sampling tests further to 83.4%. If reminder letters were sent with fixed appointments, participation was significantly higher (30 vs. 14%). If self-sampling is used after the recommended two invitations, overall screening attendance could reach the desired 80% to 85%.
NASA Astrophysics Data System (ADS)
Tarantino, Walter; Mendoza, Bernardo S.; Romaniello, Pina; Berger, J. A.; Reining, Lucia
2018-04-01
Many-body perturbation theory is often formulated in terms of an expansion in the dressed instead of the bare Green’s function, and in the screened instead of the bare Coulomb interaction. However, screening can be calculated on different levels of approximation, and it is important to define what is the most appropriate choice. We explore this question by studying a zero-dimensional model (so called ‘one-point model’) that retains the structure of the full equations. We study both linear and non-linear response approximations to the screening. We find that an expansion in terms of the screening in the random phase approximation is the most promising way for an application in real systems. Moreover, by making use of the nonperturbative features of the Kadanoff-Baym equation for the one-body Green’s function, we obtain an approximate solution in our model that is very promising, although its applicability to real systems has still to be explored.
Contribution of dielectric screening to the total capacitance of few-layer graphene electrodes
Zhan, Cheng; Jiang, De-en
2016-02-17
We apply joint density functional theory (JDFT), which treats the electrode/electrolyte interface self-consistently, to an electric double-layer capacitor (EDLC) based on few-layer graphene electrodes. The JDFT approach allows us to quantify a third contribution to the total capacitance beyond quantum capacitance (C Q) and EDL capacitance (C EDL). This contribution arises from the dielectric screening of the electric field by the surface of the few-layer graphene electrode, and we therefore term it the dielectric capacitance (C Dielec). We find that C Dielec becomes significant in affecting the total capacitance when the number of graphene layers in the electrode is moremore » than three. In conclusion, our investigation sheds new light on the significance of the electrode dielectric screening on the capacitance of few-layer graphene electrodes.« less
NASA Astrophysics Data System (ADS)
Zeller, R.; Braspenning, P. J.
1982-06-01
The charge density and the local density of states for a vacancy in Cu and for the first shell of Cu neighbours are calculated by the KKR-Green's function technique. The muffin-tin potentials for the vacancy and the neighbour shell atoms are determined self-consistently in the local density approximation of density functional theory. By the use of the proper host Green's function the embedding of this cluster of 13 perturbed muffin-tins into the infinite array of bulk Cu muffin-tin potentials is described rigorously, thus representing a solution of the embedding problem. The calculations demonstrate a rather large charge transfer of 1.1 electrons from the first neighbour shell to the vacancy.
Laskow, Bari; Figueroa, Ruben; Alfaro, Karla M; Scarinci, Isabel C; Conlisk, Elizabeth; Maza, Mauricio; Chang, Judy C; Cremer, Miriam
2017-08-01
To establish the feasibility and acceptability of home-based HPV self-sampling among women who did not attend screening appointments in rural El Salvador. In a cross-sectional study, data were collected from May 2015 to January 2016 among 60 women aged 30-59 years who were not pregnant, provided informed consent, had not been screened in 2 years, had no history of pre-cancer treatment, and did not attend a scheduled HPV screening. Participants completed questionnaires and received educational information before being given an opportunity to self-sample with the Hybrid Capture 2 High Risk HPV DNA Test. Self-sampling was accepted by 41 (68%) participants. Almost all women chose to self-sample because the process was easy (40/41, 98%), could be performed at home (40/41, 98%), and saved time (38/41, 93%), and because they felt less embarrassed (33/41, 80%). The most common reason for declining the test was not wanting to be screened (8/19, 42%). The prevalence of high-risk HPV types among women who accepted self-sampling was 17% (7/41). For most women, community-based self-sampling was an acceptable way to participate in a cervical cancer screening program. In low-resource countries, incorporating community-based self-sampling into screening programs might improve coverage of high-risk women. © 2017 International Federation of Gynecology and Obstetrics.
Rosenbaum, Alan J; Gage, Julia C; Alfaro, Karla M; Ditzian, Lauren R; Maza, Mauricio; Scarinci, Isabel C; Felix, Juan C; Castle, Philip E; Villalta, Sofia; Miranda, Esmeralda; Cremer, Miriam L
2014-08-01
To determine the acceptability of self-collected versus provider-collected sampling among women participating in public sector HPV-based cervical cancer screening in El Salvador. Two thousand women aged 30-49 years underwent self-collected and provider-collected sampling with careHPV between October 2012 and March 2013 (Qiagen, Gaithersburg, MD, USA). After sample collection, a random sample of women (n=518) were asked about their experience. Participants were questioned regarding sampling method preference, previous cervical cancer screening, HPV and cervical cancer knowledge, HPV risk factors, and demographic information. All 518 women approached to participate in this questionnaire study agreed and were enrolled, 27.8% (142 of 511 responding) of whom had not received cervical cancer screening within the past 3 years and were considered under-screened. Overall, 38.8% (n=201) preferred self-collection and 31.9% (n=165) preferred provider collection. Self-collection preference was associated with prior tubal ligation, HPV knowledge, future self-sampling preference, and future home-screening preference (P<0.05). Reasons for self-collection preference included privacy/embarrassment, ease, and less pain; reasons cited for provider-collection preference were result accuracy and provider knowledge/experience. Self-sampling was found to be acceptable, therefore screening programs could consider offering this option either in the clinic or at home. Self-sampling at home may increase coverage in low-resource countries and reduce the burden that screening places upon clinical infrastructure. Copyright © 2014 International Federation of Gynecology and Obstetrics. All rights reserved.
Bosgraaf, Remko P; Ketelaars, Pleun J W; Verhoef, Viola M J; Massuger, Leon F A G; Meijer, Chris J L M; Melchers, Willem J G; Bekkers, Ruud L M
2014-07-01
High attendance rates in cervical screening are essential for effective cancer prevention. Offering HPV self-sampling to non-responders increases participation rates. The objectives of this study were to determine why non-responders do not attend regular screening, and why they do or do not participate when offered a self-sampling device. A questionnaire study was conducted in the Netherlands from October 2011 to December 2012. A total of 35,477 non-responders were invited to participate in an HPV self-sampling study; 5347 women did opt out. Finally, 30,130 women received a questionnaire and self-sampling device. The analysis was based on 9484 returned questionnaires (31.5%) with a self-sample specimen, and 682 (2.3%) without. Among women who returned both, the main reason for non-attendance to cervical screening was that they forgot to schedule an appointment (3068; 32.3%). The most important reason to use the self-sampling device was the opportunity to take a sample in their own time-setting (4763; 50.2%). A total of 30.9% of the women who did not use the self-sampling device preferred after all to have a cervical smear taken instead. Organisational barriers are the main reason for non-attendance in regular cervical screening. Important reasons for non-responders to the regular screening to use a self-sampling device are convenience and self-control. Copyright © 2014 Elsevier Inc. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giannessi, Luca; Quattromini, Marcello
1997-06-01
We describe the model for the simulation of charged beam dynamics in radiofrequency injectors used in the three dimensional code TREDI, where the inclusion of space charge fields is obtained by means of the Lienard-Wiechert retarded potentials. The problem of charge screening is analyzed in covariant form and some general recipes for charge assignment and noise reduction are given.
Gupta, Sarah; Palmer, Christina; Bik, Elisabeth M.; Cardenas, Juan P.; Nuñez, Harold; Kraal, Laurens; Bird, Sara W.; Bowers, Jennie; Smith, Alison; Walton, Nathaniel A.; Goddard, Audrey D.; Almonacid, Daniel E.; Zneimer, Susan; Richman, Jessica; Apte, Zachary S.
2018-01-01
In most industrialized countries, screening programs for cervical cancer have shifted from cytology (Pap smear or ThinPrep) alone on clinician-obtained samples to the addition of screening for human papillomavirus (HPV), its main causative agent. For HPV testing, self-sampling instead of clinician-sampling has proven to be equally accurate, in particular for assays that use nucleic acid amplification techniques. In addition, HPV testing of self-collected samples in combination with a follow-up Pap smear in case of a positive result is more effective in detecting precancerous lesions than a Pap smear alone. Self-sampling for HPV testing has already been adopted by some countries, while others have started trials to evaluate its incorporation into national cervical cancer screening programs. Self-sampling may result in more individuals willing to participate in cervical cancer screening, because it removes many of the barriers that prevent women, especially those in low socioeconomic and minority populations, from participating in regular screening programs. Several studies have shown that the majority of women who have been underscreened but who tested HPV-positive in a self-obtained sample will visit a clinic for follow-up diagnosis and management. In addition, a self-collected sample can also be used for vaginal microbiome analysis, which can provide additional information about HPV infection persistence as well as vaginal health in general. PMID:29686981
Chen, Zehua; Zhang, Du; Jin, Ye; Yang, Yang; Su, Neil Qiang; Yang, Weitao
2017-09-21
To describe static correlation, we develop a new approach to density functional theory (DFT), which uses a generalized auxiliary system that is of a different symmetry, such as particle number or spin, from that of the physical system. The total energy of the physical system consists of two parts: the energy of the auxiliary system, which is determined with a chosen density functional approximation (DFA), and the excitation energy from an approximate linear response theory that restores the symmetry to that of the physical system, thus rigorously leading to a multideterminant description of the physical system. The electron density of the physical system is different from that of the auxiliary system and is uniquely determined from the functional derivative of the total energy with respect to the external potential. Our energy functional is thus an implicit functional of the physical system density, but an explicit functional of the auxiliary system density. We show that the total energy minimum and stationary states, describing the ground and excited states of the physical system, can be obtained by a self-consistent optimization with respect to the explicit variable, the generalized Kohn-Sham noninteracting density matrix. We have developed the generalized optimized effective potential method for the self-consistent optimization. Among options of the auxiliary system and the associated linear response theory, reformulated versions of the particle-particle random phase approximation (pp-RPA) and the spin-flip time-dependent density functional theory (SF-TDDFT) are selected for illustration of principle. Numerical results show that our multireference DFT successfully describes static correlation in bond dissociation and double bond rotation.
Implications of the Babinet Principle for Casimir interactions
NASA Astrophysics Data System (ADS)
Maghrebi, Mohammad F.; Jaffe, Robert L.; Abravanel, Ronen
2011-09-01
We formulate the Babinet Principle (BP) as a relation between scattering amplitudes and combine it with multiple scattering techniques to derive new properties of electromagnetic Casimir forces. We show that the Casimir force exerted by a planar conductor or dielectric on a self-complementary perforated planar mirror is approximately half that on a uniform mirror independent of the distance between them. Also, the BP suggests that Casimir edge effects are generically anomalously small. Furthermore, the BP can be used to relate any planar object to its complementary geometry, a relation we use to estimate Casimir forces between two screens with apertures.
Electronic structure and magneto-optical effects in CeSb
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liechtenstein, A.I.; Antropov, V.P.; Harmon, B.N.
1994-04-15
The electronic structure and magneto-optical spectra of CeSb have been calculated using the self-consistent local-density approximation with explicit on-site Coulomb parameters for the correlated [ital f] state of cerium. The essential electronic structure of cerium antimonide consists of one occupied [ital f] band, predominantly with orbital [ital m]=[minus]3 character and spin [sigma]=1 located 2 eV below the Fermi level and interacting with broad Sb [ital p] bands crossing [ital E][sub [ital F
Self-examination of the breast; BSE; Breast cancer - BSE; Breast cancer screening - self exam ... chap 15. US Preventive Services Task Force website. Breast cancer: screening. www.uspreventiveservicestaskforce.org/Page/Document/UpdateSummaryFinal/breast- ...
Patient education and multiphasic screening: it can change behavior.
Rodnick, J E; Bubb, K
1978-03-01
Two hundred ninety-two residents of Sonoma County, California, underwent multiphasic screeening and two sessions of group patient education aimed at reducing risk factors for cardiovascular disease, cancer, and automobile accidents. Approximately one year later all the participants were retested. A significant reduction was noted in systolic blood pressure in men and women, ages 50 to 70, cholesterol in men over age 40, and reported alcohol consumption in men. A significant increase was noted in the reported frequency of monthly breast self-examination in women, and in the amount of exercise and percentage of time seat belts were used in both sexes. No change was noted in reported amount of cigarette smoking, weight, fasting blood glucose, and triglycerides. The combined use of health hazard appraisal, multiphasic screening, and patient education can lead to a reduction in cardiac and other risk factors in well-motivated groups.
Chiu, Han-Mo; Chen, Sam Li-Sheng; Yen, Amy Ming-Fang; Chiu, Sherry Yueh-Hsia; Fann, Jean Ching-Yuan; Lee, Yi-Chia; Pan, Shin-Liang; Wu, Ming-Shiang; Liao, Chao-Sheng; Chen, Hsiu-Hsi; Koong, Shin-Lan; Chiou, Shu-Ti
2015-09-15
The effectiveness of fecal immunochemical testing (FIT) in reducing colorectal cancer (CRC) mortality has not yet been fully assessed in a large, population-based service screening program. A prospective cohort study of the follow-up of approximately 5 million Taiwanese from 2004 to 2009 was conducted to compare CRC mortality for an exposed (screened) group and an unexposed (unscreened) group in a population-based CRC screening service targeting community residents of Taiwan who were 50 to 69 years old. Given clinical capacity, this nationwide screening program was first rolled out in 2004. In all, 1,160,895 eligible subjects who were 50 to 69 years old (ie, 21.4% of the 5,417,699 subjects of the underlying population) participated in the biennial nationwide screening program by 2009. The actual effectiveness in reducing CRC mortality attributed to the FIT screening was 62% (relative rate for the screened group vs the unscreened group, 0.38; 95% confidence interval, 0.35-0.42) with a maximum follow-up of 6 years. The 21.4% coverage of the population receiving FIT led to a significant 10% reduction in CRC mortality (relative rate, 0.90; 95% confidence interval, 0.84-0.95) after adjustments for a self-selection bias. This large, prospective Taiwanese cohort undergoing population-based FIT screening for CRC had the statistical power to demonstrate a significant CRC mortality reduction, although the follow-up time was short. Although such findings are informative for health decision makers, continued follow-up of this large cohort will be required to estimate the long-term impact of FIT screening if the covered population is expanded. © 2015 American Cancer Society.
Association Between Sexually Transmitted Diseases and Young Adults' Self-reported Abstinence
DiClemente, Ralph J.; Danner, Fred; Crosby, Richard A.
2011-01-01
OBJECTIVE: Self-reported behavior has been the cornerstone of sexual health research and clinical practice, yet advances in sexually transmitted disease (STD) screening provide researchers with the opportunity to objectively quantify sexual risk behaviors. However, the extent to which young adults' laboratory-confirmed STD results and self-reported sexual behaviors are consistent has not been assessed in a nationally representative sample. PATIENTS AND METHODS: Data are derived from participants who completed wave 3 in the National Longitudinal Study of Adolescent Health. Young adults (N = 14 012) completed an audio computer-assisted self-interviewing survey and provided a urine specimen to detect the presence of Chlamydia trachomatis and Neisseria gonorrhoeae, and a polymerase chain reaction assay to detect Trichomonas vaginalis. RESULTS: More than 10% of young adults with a laboratory-confirmed positive STD result reported abstaining from sexual intercourse in the 12 months before assessment and STD testing. After controlling for several sociodemographic factors, self-reported sex (versus those who reported abstinence) in the previous 12 months was significantly associated with testing positive, but the odds of testing positive were only slightly more than twofold (adjusted odds ratio: 2.11 [95% confidence interval: 2.097–2.122]). CONCLUSIONS: Findings indicate discrepancy between young adults' positive STD status and self-reported sexual behavior. No significant correlates of discrepant reporting were identified. From a clinical standpoint, the discrepancies between STD positivity and self-reported sexual behavior observed in this nationally representative sample suggest that routine STD screening may be beneficial and necessary to reduce STD morbidity among young adults. PMID:21199852
Madzima, Tina R; Vahabi, Mandana; Lofters, Aisha
2017-08-01
To provide a focused critical review of the literature on the acceptability, feasibility, and uptake of human papillomavirus (HPV) self-sampling among hard-to-reach women. A focused search to obtain relevant literature published in English between 1997 and 2015 was done using PubMed and EMBASE using search terms including HPV self-test or HPV self-sample or HPV kit in combination with acceptability or feasibility . Only studies that focused on never-screened or underscreened populations were included in this review. Human papillomavirus self-sampling was found to be highly acceptable and feasible among these hard-to-reach women across most studies. Mailing of self-sampling kits has been shown to increase participation among hard-to reach women. Some concerns remain regarding adherence to further follow-up among high-risk women with positive test results for HPV after screening. There is a strong body of evidence to support the usefulness of HPV self-sampling in increasing participation of hard-to-reach women in screening programs (level I evidence). Convenience, privacy, ease of use, and, likely, cost-effectiveness of HPV self-sampling are driving forces in its emerging role in cervical cancer screening among hard-to-reach women. Key barriers to participation could be addressed by overcoming disparities in HPV-related knowledge and perceptions about cervical cancer screening. Copyright© the College of Family Physicians of Canada.
Hajek, André; Bock, Jens-Oliver; König, Hans-Helmut
2017-12-01
Within the framework of the health-belief model, some studies exist investigating the association between illness-specific psychosocial factors and the use of cancer screenings. However, studies investigating the association between general psychosocial factors and the use of cancer screenings are missing. Thus, this study aimed at examining the association between well-established general psychosocial factors and the use of cancer screenings. Data were gathered from a large, population-based sample of community-dwelling individuals aged 40 and above in Germany (n = 7673; in 2014). Loneliness, cognitive well-being, affective well-being (negative and positive affect), optimism, self-efficacy, self-esteem, self-regulation, perceived autonomy, perceived stress, and perceived social exclusion were used as general psychosocial factors. Furthermore, individuals were asked whether they regularly underwent early cancer screening in the past years (yes; no). A total of 65.6% of the individuals used cancer screening. Adjusting for sociodemographic factors, self-rated health, morbidity and lifestyle factors, multiple logistic regressions revealed that the use of cancer screening is positively associated with decreased loneliness, cognitive well-being, optimism, self-efficacy, self-esteem, self-regulation, perceived autonomy, decreased perceived stress, decreased perceived social exclusion, and positive affect, while it is not associated with negative affect. This study stresses the strong association between general psychosocial factors and the use of cancer screening. This knowledge might be fruitful to address individuals at risk for underuse. © 2017 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.
Development of a menu of performance tests self-administered on a portable microcomputer
NASA Technical Reports Server (NTRS)
Wilkes, Robert L.; Kuntz, Lois-Ann; Kennedy, Robert S.
1987-01-01
Eighteen cognitive, motor, and information processing performance subtests were screened for self-administration over 10 trials by 16 subjects. When altered presentation forms of the same test were collectively considered, the battery composition was reduced to 10 distinctly different measures. A fully automated microbased testing system was employed in presenting the battery of subtests. Successful self-administration of the battery provided for the field testing of the automated system and facilitated convenient data collection. Total test administration time was 47.2 minutes for each session. Results indicated that nine of the tests stabilized, but for a short battery of tests only five are recommended for use in repeated-measures research. The five recommended tests include: the Tapping series, Number Comparison, Short-term Memory, Grammatical Reasoning, and 4-Choice Reaction Time. These tests can be expected to reveal three factors: (1) cognition, (2) processing quickness, and (3) motor. All the tests stabilized in 24 minutes, or approximately two 12-minute sessions.
NASA Astrophysics Data System (ADS)
Gambacurta, D.; Grasso, M.; Vasseur, O.
2018-02-01
The second random-phase-approximation model corrected by a subtraction procedure designed to cure double counting, instabilities, and ultraviolet divergences, is employed for the first time to analyze the dipole strength and polarizability in 48Ca. All the terms of the residual interaction are included, leading to a fully self-consistent scheme. Results are illustrated with two Skyrme parametrizations, SGII and SLy4. Those obtained with the SGII interaction are particularly satisfactory. In this case, the low-lying strength below the neutron threshold is well reproduced and the giant dipole resonance is described in a very satisfactory way especially in its spreading and fragmentation. Spreading and fragmentation are produced in a natural way within such a theoretical model by the coupling of 1 particle-1 hole and 2 particle-2 hole configurations. Owing to this feature, we may provide for the electric polarizability as a function of the excitation energy a curve with a similar slope around the centroid energy of the giant resonance compared to the corresponding experimental results. This represents a considerable improvement with respect to previous theoretical predictions obtained with the random-phase approximation or with several ab-initio models. In such cases, the spreading width of the excitation cannot be reproduced and the polarizability as a function of the excitation energy displays a stiff increase around the predicted centroid energy of the giant resonance.
NASA Astrophysics Data System (ADS)
Mauri, Francesco
Anharmonic effects can generally be treated within perturbation theory. Such an approach breaks down when the harmonic solution is dynamically unstable or when the anharmonic corrections of the phonon energies are larger than the harmonic frequencies themselves. This situation occurs near lattice-related second-order phase-transitions such as charge-density-wave (CDW) or ferroelectric instabilities or in H-containing materials, where the large zero-point motion of the protons results in a violation of the harmonic approximation. Interestingly, even in these cases, phonons can be observed, measured, and used to model transport properties. In order to treat such cases, we developed a stochastic implementation of the self-consistent harmonic approximation valid to treat anharmonicity in the nonperturbative regime and to obtain, from first-principles, the structural, thermodynamic and vibrational properties of strongly anharmonic systems. I will present applications to the ferroelectric transitions in SnTe, to the CWD transitions in NbS2 and NbSe2 (in bulk and monolayer) and to the hydrogen-bond symmetrization transition in the superconducting hydrogen sulfide system, that exhibits the highest Tc reported for any superconductor so far. In all cases we are able to predict the transition temperature (pressure) and the evolution of phonons with temperature (pressure). This project has received funding from the European Union's Horizon 2020 research and innovation programme under Grant agreement No. 696656 GrapheneCore1.
Analysis of Ethnic Admixture in Prostate Cancer
2006-12-01
low penetrant genes have been identified as potential PCA suscept- ibility genes. These candidate genes include SRD5A2 (MIM 607306), CYP3A4 (MIM 124010...progression [13]. The CDH1gene is located at 16q22.1 and consists of 16 exons spanning approximately 100 kb of genomic DNA. Several polymorphisms, germline and...upstreamof theATGstart site and all 16 exons of CDH1 were screened for DNA sequence variation by denaturing high-performance liquid chro- matography
On basis set superposition error corrected stabilization energies for large n-body clusters.
Walczak, Katarzyna; Friedrich, Joachim; Dolg, Michael
2011-10-07
In this contribution, we propose an approximate basis set superposition error (BSSE) correction scheme for the site-site function counterpoise and for the Valiron-Mayer function counterpoise correction of second order to account for the basis set superposition error in clusters with a large number of subunits. The accuracy of the proposed scheme has been investigated for a water cluster series at the CCSD(T), CCSD, MP2, and self-consistent field levels of theory using Dunning's correlation consistent basis sets. The BSSE corrected stabilization energies for a series of water clusters are presented. A study regarding the possible savings with respect to computational resources has been carried out as well as a monitoring of the basis set dependence of the approximate BSSE corrections. © 2011 American Institute of Physics
Rappaport, B I; Pagliaccio, D; Pine, D S; Klein, D N; Jarcho, J M
2017-10-01
The Screen for Child Anxiety and Related Emotional Disorder (SCARED) may be differentially sensitive to detecting specific or comorbid anxiety diagnoses in treatment-seeking and non-treatment-seeking youth. We assessed the SCARED's discriminant validity, diagnostic utility, and informant agreement using parent- and self-report from healthy and treatment-seeking anxious youth (Study 1, N=585) and from non-treatment-seeking anxious youth (Study 2, N=331) diagnosed with generalized anxiety disorder (GAD), social anxiety disorder (SAD), or comorbid GAD+SAD. Among treatment-seeking youth, the SCARED showed good diagnostic utility and specificity, differentiating healthy, comorbid, and non-comorbid anxious youth. Child-parent agreement was modest: healthy child self-reports were higher than parent-reports whereas anxious child self-reports were similar or lower than parent-reports. Less consistent results emerged for diagnostic utility, specificity, and informant agreement among non-treatment-seeking youth. Given the number of non-treatment seeking anxious youth (N=33), generalizability of these findings may be limited. Together, results suggest informants may provide distinct information about children's anxiety symptoms. Copyright © 2017 Elsevier Ltd. All rights reserved.
Rappaport, B. I.; Pagliaccio, D.; Pine, D. S.; Klein, D. N.; Jarcho, J. M.
2017-01-01
The Screen for Child Anxiety and Related Emotional Disorder (SCARED) may be differentially sensitive to detecting specific or comorbid anxiety diagnoses in treatment-seeking and non-treatment-seeking youth. We assessed the SCARED’s discriminant validity, diagnostic utility, and informant agreement using parent- and self-report from healthy and treatment-seeking anxious youth (Study 1, N=585) or from non-treatment-seeking anxious youth (Study 2, N=331) diagnosed with generalized anxiety disorder (GAD), social anxiety disorder (SAD), or comorbid GAD+SAD. Among treatment-seeking youth, the SCARED showed good diagnostic utility and specificity, differentiating healthy, comorbid, and non-comorbid anxious youth. Child-parent agreement was modest: healthy child self-reports were higher than parent-reports whereas anxious child self-reports were similar or lower than parent-reports. Less consistent results emerged for diagnostic utility, specificity, and informant agreement among non-treatment-seeking youth. Given the number of non-treatment seeking anxious youth (N=33), generalizability of these findings may be limited. Together, results suggest informants may provide distinct information about children’s anxiety symptoms. PMID:28886420
Reisner, Sari L; Deutsch, Madeline B; Peitzmeier, Sarah M; White Hughto, Jaclyn M; Cavanaugh, Timothy P; Pardee, Dana J; McLean, Sarah A; Panther, Lori A; Gelman, Marcy; Mimiaga, Matthew J; Potter, Jennifer E
2018-01-01
High-risk human papillomavirus (hrHPV) causes virtually all cervical cancers. Trans masculine (TM) people (those assigned female at birth who identify with a gender other than female) have low uptake of conventional cervical cancer screening. Self-collected hrHPV DNA testing has high levels of acceptability among cisgender (non-transgender) females and may support increased cervical cancer screening uptake in TM individuals. To assess the test performance and acceptability of self-collected vaginal specimens in comparison to provider-collected cervical swabs for hrHPV DNA detection in TM individuals ages 21-64 years. Between March 2015-September 2016, 150 TM participants with a cervix (mean age = 27.5 years; SD = 5.7) completed a one-time study visit comprised of a self-report survey, self-collected vaginal HPV DNA swab, clinician-administered cervical HPV swab, and brief interview on acceptability of clinical procedures. Participants were randomized to complete either self- or provider-collection first to minimize ordering effects. Self- and provider-collected samples were tested for 13 hrHPV DNA types using a DNA Hybridization Assay. The primary outcome variable was the concordance (kappa statistic) and performance (sensitivity, specificity) of self-collected vaginal HPV DNA specimens versus provider-collected cervical HPV swabs as the gold standard. Of the 131 participants completing both the self- and provider-collected HPV tests, 21 cases of hrHPV were detected by the provider cervical swab (gold standard; 16.0% hrHPV prevalence); 15 of these cases were accurately detected by the self-collected vaginal swab (71.4% concordance) (Kappa = 0.75, 95% Confidence Interval [CI]: 0.59, 0.92; p<0.001). Compared to the provider-collected cervical hrHPV DNA sample (gold standard), the self-collected vaginal hrHPV DNA test demonstrated a sensitivity of 71.4% (95% CI: 0.52, 0.91; p = 0.0495) and specificity of 98.2% (95% CI: 0.96, 1.00; p<0.0001). Over 90% of participants endorsed a preference for the self-collected vaginal swab over provider-collected cervical swab. Self-collected vaginal swabs are highly acceptable to TM as a means to test for hrHPV DNA. Test performance of this self-collection method for hrHPV detection in TM is consistent with previous studies in cisgender females. Self-collected vaginal swab testing for hrHPV DNA represents a reasonable and patient-centered strategy for primary cervical cancer screening in TM patients unwilling to undergo provider collection of specimens via speculum exam.
Thompson, V L Sanders; Harris, J; Clark, E M; Purnell, J; Deshpande, A D
2015-01-01
The importance of sociocultural constructs as influences on cancer attitudes and screening has been established in the literature. This paper reports on the efforts to explore alternatives to sociocultural constructs previously associated with African-American cancer screening, but with low acceptance among community members or incomplete measurement (empowerment and collectivism) and develop a measure for a recently identified construct of interest (privacy). We report preliminary psychometric data on these sociocultural scales and their associations with cancer attitudes. African-Americans (N = 1021), 50-75 years of age participated in this study. Participants were identified via a listed sample and completed a telephone survey administered via call center. Sociocultural attitudes were assessed using items identified through computerized database searches, reviewed by advisory panels, edited and tested using cognitive response strategies. Cancer screening pros and cons, cancer worry, perceived cancer risk, colorectal cancer (CRC) screening subjective norms, and perceived self-efficacy for colorectal cancer screening (CRCS) were also assessed. Confirmatory factor analyses and multivariate analyses were conducted to provide support for the validity of the constructs and to understand the associations among the selected sociocultural constructs (empowerment, collectivism, and privacy) and cancer beliefs and attitudes (CRC perceived benefits and barriers, perceived risks, subjective norms, and perceived behavioral control/self-efficacy). Consistent with the literature, the factor analytic model (RMSEA for the model was .062; 90% CI: .060-.065) provided support for the empowerment, collectivism, and privacy constructs. The modified collectivism and privacy scales had acceptable reliability. The privacy scale demonstrated the strongest associations with measures of cancer beliefs and attitudes. The implication of the findings and need for further scale development activities is discussed.
Sanders Thompson, V. L.; Harris, J.; Clark, E.M.; Purnell, J.; Deshpande, A.D.
2014-01-01
The importance of socio-cultural constructs as influences on cancer attitudes and screening has been established in the literature. This paper reports on efforts to explore alternatives to constructs previously associated with African American cancer screening, but with low acceptance among community members or incomplete measurement (empowerment and collectivism) and develop a measure for a recently identified construct of interest (privacy). We report preliminary psychometric data on these socio-cultural scales and their associations with cancer attitudes. African Americans (N=1021), 50 to 75 years of age participated in this study. Participants were identified via a listed sample and completed a telephone survey administered via call center. Socio-cultural attitudes were assessed using items identified through computerized database searches, reviewed by advisory panels, edited and tested using cognitive response strategies. Cancer screening pros and cons, cancer worry, perceived cancer risk, colorectal cancer screening subjective norms, and perceived self-efficacy for colorectal cancer screening were also assessed. Confirmatory factor analyses and multivariate analyses were conducted to provide support for the validity of the constructs and to understand the associations among the selected socio-cultural constructs (empowerment, collectivism and empowerment) and cancer beliefs and attitudes (CRC perceived benefits and barriers, perceived risks, subjective norms, and perceived behavioral control/self-efficacy). Consistent with the literature, the factor analytic model (RMSEA for the model was 0.062; 90% CI: 0.060-0.065) provided support for the empowerment, collectivism and privacy constructs. The modified collectivism and privacy scales had acceptable reliability. The privacy scale demonstrated the strongest associations with measures of cancer beliefs and attitudes. The implication of the findings and need for further scale development activities is discussed. PMID:24628025
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hattori, Koichi, E-mail: khattori@yonsei.ac.kr; Itakura, Kazunori, E-mail: kazunori.itakura@kek.jp; Department of Particle and Nuclear Studies, Graduate University for Advanced Studies
2013-07-15
We compute the refractive indices of a photon propagating in strong magnetic fields on the basis of the analytic representation of the vacuum polarization tensor obtained in our previous paper. When the external magnetic field is strong enough for the fermion one-loop diagram of the polarization tensor to be approximated by the lowest Landau level, the propagating mode in parallel to the magnetic field is subject to modification: The refractive index deviates from unity and can be very large, and when the photon energy is large enough, the refractive index acquires an imaginary part indicating decay of a photon intomore » a fermion–antifermion pair. We study dependences of the refractive index on the propagating angle and the magnetic-field strength. It is also emphasized that a self-consistent treatment of the equation which defines the refractive index is indispensable for accurate description of the refractive index. This self-consistent treatment physically corresponds to consistently including the effects of back reactions of the distorted Dirac sea in response to the incident photon. -- Highlights: •Vacuum birefringence and photon decay are described by the complex refractive index. •Resummed photon vacuum polarization tensor in the lowest Landau level is used. •Back reactions from the distorted Dirac sea are self-consistently taken into account. •Self-consistent treatment drastically changes structure in photon energy dependence. •Dependences on photon propagation angle and magnetic-field strength are presented.« less
Shafeei, Asrin; Mokhtarinia, Hamid Reza; Maleki-Ghahfarokhi, Azam; Piri, Leila
2017-08-01
Observational study. To cross-culturally translate the Orebro Musculoskeletal Pain Screening Questionnaire (OMPQ) into Persian and then evaluate its psychometric properties (reliability, validity, ceiling, and flooring effects). To the authors' knowledge, prior to this study there has been no validated instrument to screen the risk of chronicity in Persian-speaking patients with low back pain (LBP) in Iran. The OMPQ was specifically developed as a self-administered screening tool for assessing the risk of LBP chronicity. The forward-backward translation method was used for the translation and cross-cultural adaptation of the original questionnaire. In total, 202 patients with subacute LBP completed the OMPQ and the pain disability questionnaire (PDQ), which was used to assess convergent validity. 62 patients completed the OMPQ a week later as a retest. Slight changes were made to the OMPQ during the translation/cultural adaptation process; face validity of the Persian version was obtained. The Persian OMPQ showed excellent test-retest reliability (intraclass correlation coefficient=0.89). Its internal consistency was 0.71, and its convergent validity was confirmed by good correlation coefficient between the OMPQ and PDQ total scores ( r =0.72, p <0.05). No ceiling or floor effects were observed. The Persian version of the OMPQ is acceptable for the target society in terms of face validity, construct validity, reliability, and consistency. It is therefore considered a useful instrument for screening Iranian patients with LBP.
A multiplex degenerate PCR analytical approach targeting to eight genes for screening GMOs.
Guo, Jinchao; Chen, Lili; Liu, Xin; Gao, Ying; Zhang, Dabing; Yang, Litao
2012-06-01
Currently, the detection methods with lower cost and higher throughput are the major trend in screening genetically modified (GM) food or feed before specific identification. In this study, we developed a quadruplex degenerate PCR screening approach for more than 90 approved GMO events. This assay is consisted of four PCR systems targeting on nine DNA sequences from eight trait genes widely introduced into GMOs, such as CP4-EPSPS derived from Acetobacterium tumefaciens sp. strain CP4, phosphinothricin acetyltransferase gene derived from Streptomyceshygroscopicus (bar) and Streptomyces viridochromogenes (pat), and Cry1Ab, Cry1Ac, Cry1A(b/c), mCry3A, and Cry3Bb1 derived from Bacillus thuringiensis. The quadruplex degenerate PCR assay offers high specificity and sensitivity with the absolute limit of detection (LOD) of approximate 80targetcopies. Furthermore, the applicability of the quadruplex PCR assay was confirmed by screening either several artificially prepared samples or samples of Grain Inspection, Packers and Stockyards Administration (GIPSA) proficiency program. Copyright © 2011 Elsevier Ltd. All rights reserved.
Culture modulates implicit ownership-induced self-bias in memory.
Sparks, Samuel; Cunningham, Sheila J; Kritikos, Ada
2016-08-01
The relation of incoming stimuli to the self implicitly determines the allocation of cognitive resources. Cultural variations in the self-concept shape cognition, but the extent is unclear because the majority of studies sample only Western participants. We report cultural differences (Asian versus Western) in ownership-induced self-bias in recognition memory for objects. In two experiments, participants allocated a series of images depicting household objects to self-owned or other-owned virtual baskets based on colour cues before completing a surprise recognition memory test for the objects. The 'other' was either a stranger or a close other. In both experiments, Western participants showed greater recognition memory accuracy for self-owned compared with other-owned objects, consistent with an independent self-construal. In Experiment 1, which required minimal attention to the owned objects, Asian participants showed no such ownership-related bias in recognition accuracy. In Experiment 2, which required attention to owned objects to move them along the screen, Asian participants again showed no overall memory advantage for self-owned items and actually exhibited higher recognition accuracy for mother-owned than self-owned objects, reversing the pattern observed for Westerners. This is consistent with an interdependent self-construal which is sensitive to the particular relationship between the self and other. Overall, our results suggest that the self acts as an organising principle for allocating cognitive resources, but that the way it is constructed depends upon cultural experience. Additionally, the manifestation of these cultural differences in self-representation depends on the allocation of attentional resources to self- and other-associated stimuli. Crown Copyright © 2016. Published by Elsevier B.V. All rights reserved.
A molecularly based theory for electron transfer reorganization energy.
Zhuang, Bilin; Wang, Zhen-Gang
2015-12-14
Using field-theoretic techniques, we develop a molecularly based dipolar self-consistent-field theory (DSCFT) for charge solvation in pure solvents under equilibrium and nonequilibrium conditions and apply it to the reorganization energy of electron transfer reactions. The DSCFT uses a set of molecular parameters, such as the solvent molecule's permanent dipole moment and polarizability, thus avoiding approximations that are inherent in treating the solvent as a linear dielectric medium. A simple, analytical expression for the free energy is obtained in terms of the equilibrium and nonequilibrium electrostatic potential profiles and electric susceptibilities, which are obtained by solving a set of self-consistent equations. With no adjustable parameters, the DSCFT predicts activation energies and reorganization energies in good agreement with previous experiments and calculations for the electron transfer between metallic ions. Because the DSCFT is able to describe the properties of the solvent in the immediate vicinity of the charges, it is unnecessary to distinguish between the inner-sphere and outer-sphere solvent molecules in the calculation of the reorganization energy as in previous work. Furthermore, examining the nonequilibrium free energy surfaces of electron transfer, we find that the nonequilibrium free energy is well approximated by a double parabola for self-exchange reactions, but the curvature of the nonequilibrium free energy surface depends on the charges of the electron-transferring species, contrary to the prediction by the linear dielectric theory.
Baird, Chelsea; Lovell, Janaka; Johnson, Marilyn; Shiell, Kerrie; Ibrahim, Joseph E
2017-08-01
To determine the characteristics of persons with cognitive impairment being able to self-manage in chronic obstructive pulmonary disease (COPD). In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance this systematic review examined all studies in English from 1st January 2000 to 20 February 2016, describing the relationship between cognition and COPD self-management domains in older community dwelling persons with dementia or cognitive impairment. Of 4474 studies identified, thirteen studies were eligible for inclusion. No studies differentiated populations into recognized dementia subtypes. Study aims were variable; most (n = 7) examined inhaler competency alone. Studies identified a link between worsening cognition and the need for assistance in activities of daily living. Only one study evaluated the impact of cognition on overall self-management and found no association between cognitive impairment and self-rated self-management. Mild degrees of cognitive impairment were associated with reduced symptom recall. Cognitive impairment in COPD was associated with high degrees of inhaler incompetency. Basic cognitive screening tests were able to predict inhaler incompetence with reduced overall cognitive function, dyspraxia, and/or executive function identified as predictors of incompetency. Multiple measures of disability consistently demonstrated that cognitive impairment in COPD significantly increased the need for assistance in many aspects of daily living, treatment adherence, and effective self-management. Given the nature of neuropsychological deficits seen in COPD, dedicated screening tools are required. Future research should investigate the impact of cognitive dysfunction in COPD and identify how to support those that lack capacity to self-manage. Copyright © 2017 Elsevier Ltd. All rights reserved.
Echouffo-Tcheugui, Justin B; Simmons, Rebecca K; Prevost, A Toby; Williams, Kate M; Kinmonth, Ann-Louise; Wareham, Nicholas J; Griffin, Simon J
2015-03-01
There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors. We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis. Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71-1.15); SF-8 physical health summary score as an indicator of self-rated health status (β -0.33, 95% CI, -1.80 to 1.14); EQ-5D visual analogue score (β: 0.80, 95% CI, -1.28 to 2.87); total physical activity (β 0.50, 95% CI, -4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (β 0.14, 95% CI, -1.07 to 1.35). Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years. © 2015 Annals of Family Medicine, Inc.
Echouffo-Tcheugui, Justin B.; Simmons, Rebecca K.; Prevost, A. Toby; Williams, Kate M.; Kinmonth, Ann-Louise; Wareham, Nicholas J.; Griffin, Simon J.
2015-01-01
PURPOSE There is limited trial evidence concerning the long-term effects of screening for type 2 diabetes on population morbidity. We examined the effect of a population-based diabetes screening program on cardiovascular morbidity, self-rated health, and health-related behaviors. METHODS We conducted a pragmatic, parallel-group, cluster-randomized controlled trial of diabetes screening (the ADDITION-Cambridge study) including 18,875 individuals aged 40 to 69 years at high risk of diabetes in 32 general practices in eastern England (27 practices randomly allocated to screening, 5 to no-screening for control). Of those eligible for screening, 466 (2.9%) were diagnosed with diabetes. Seven years after randomization, a random sample of patients was sent a postal questionnaire: 15% from the screening group (including diabetes screening visit attenders and non-attenders) and 40% from the no-screening control group. Self-reported cardiovascular morbidity, self-rated health (using the SF-8 Health Survey and EQ-5D instrument), and health behaviors were compared between trial groups using an intention-to-screen analysis. RESULTS Of the 3,286 questionnaires mailed out, 1,995 (61%) were returned, with 1,945 included in the analysis (screening: 1,373; control: 572). At 7 years, there were no significant differences between the screening and control groups in the proportion of participants reporting heart attack or stroke (OR = 0.90, 95% CI, 0.71–1.15); SF-8 physical health summary score as an indicator of self-rated health status (β −0.33, 95% CI, −1.80 to 1.14); EQ-5D visual analogue score (β: 0.80, 95% CI, −1.28 to 2.87); total physical activity (β 0.50, 95% CI, −4.08 to 5.07); current smoking (OR 0.97, 95% CI, 0.72 to 1.32); and alcohol consumption (β 0.14, 95% CI, −1.07 to 1.35). CONCLUSIONS Invitation to screening for type 2 diabetes appears to have limited impact on population levels of cardiovascular morbidity, self-rated health status, and health behavior after 7 years. PMID:25755036
Assessing the risk of self-harm in an adult offender population: an incidence cohort study.
Horton, Mike; Wright, Nat; Dyer, Wendy; Wright-Hughes, Alex; Farrin, Amanda; Mohammed, Zanib; Smith, Jamie; Heyes, Tom; Gilbody, Simon; Tennant, Alan
2014-10-01
Self-harm is common among prisoners, particularly female prisoners. In 2007, concerned about the rising incidence, the prison service introduced a care-planning system called Assessment, Care in Custody, and Teamwork (ACCT). To date, it does not incorporate a standardised diagnostic test to estimate the risk of future self-harm. To identify potential screening instruments, or items from those instruments, to predict the risk of self-harm among prisoners. Prisoners who had been assigned to an ACCT during the recruitment period. A multistage prospective cohort study. Following a pilot study, instruments were administered to prisoners by interview at baseline, and followed up for 6 months (or until point of release if this was sooner) to ascertain self-harm status. Instruments were assessed for unidimensionality, scalability (Mokken) and quantitative structure (Rasch). Area under the curve (AUC) analysis was used to examine the ability of instruments and/or their items to predict future self-harm. Cox proportional hazards regression models were used to examine the multivariate predictive ability of the scales and various sociodemographic and sentencing factors. Three prisons (including one women's prison) in northern England. A set of standardised questionnaires, including the Prison Screening Questionnaire (PriSnQuest), Revised Borderline Symptom List-23 (frequency-based responses) (BSL-23-F), Self-Harm Inventory (SHI), Patient Health Questionnaire (PHQ-9) and the Clinical Outcomes in Routine Evaluation - Outcome Measure (CORE-OM), together with sociodemographic and sentencing data. In total, 450 prisoners consented to participate in the study, of whom 26% were female. The mean age of participants was 31.2 years. Over half of male prisoners recruited were on remand, compared with just over one-fifth (22.6%) of female prisoners. The average tariff of those sentenced was 41 months, of which 14.7 months, on average, had been served. Just over one-third of ACCTs had been initiated because of a known self-harm event, and over one-quarter (27.8%) of participants self-harmed during the follow-up period. Thus, almost half (46.7%) of those entered into the study were reported to have self-harmed, either from their index ACCT, or subsequently, or both. Cutting was the most frequent behaviour (51%). All screening instruments showed some evidence of unidimensionality, and four out of five showed scaling criteria consistent with ordinal scaling, so verifying the validity of the cut points. However, many showed gender bias and failure to fit the Rasch measurement model. While a resolution was made in most cases, both ordinal raw scores and latent interval scale estimates failed to show predictive value when applied within AUC analysis (0.491-0.566) or adjusted Cox proportional hazards models. However, good predictive values were shown for gender-specific sets of items, thus providing easily applied screening indexes. While four out of five potential screening instruments were found to have acceptable psychometric properties within this setting, their predictive validity of all instruments was poor under AUC analysis. Gender-specific item sets were put together to form two screening indexes with formative indicators which gave reasonable AUC values, particularly so for females. The indexes provide identification of low-medium-high risk of self-harm, and so may help to inform potential care pathways and decisions to sign prisoners off from the ACCT. Future work should concentrate on refining a set of predictive screening items among different offender populations and investigating the time point at which this set of items should be administered. Future work may also look at the different magnitudes of risk as indicators for care pathways. The National Institute for Health Research Health Technology Assessment programme.
Youth Justice staff attitudes towards screening for self-harm.
Knowles, Sarah E; Townsend, Ellen; Anderson, Martin P
2012-09-01
Young offenders are recognised as a high-risk group for suicidal behaviour. It is essential that the screening used to identify those at risk and refer them to mental health services is effective, especially in community settings where service utilisation is low. Staff attitudes towards screening for suicide and self-harm are likely to influence how a young offender engages with the screening process. Our study is the first to explore community youth justice staff attitudes towards, and perceptions of, screening for self-harmful behaviour. Eight semi-structured interviews were conducted at an English Youth Offending Team in June 2006 with staff who had used the suicide screening tool with young offenders. Data were analysed using Interpretative Phenomenological Analysis. Staff attitudes towards working within the screening system varied along two dimensions. The first 'active/passive' dimension related to perceived confidence in dealing with self-harm. The second 'positive/negative' dimension related to perceptions of the benefits of screening and the effectiveness of mental health provision for young offenders. Results indicate that barriers to effective screening must be tackled at both individual and organisational levels. The model of attitudes presented here could be used to increase understanding of how staff can be supported to engage effectively with the screening system. © 2012 Blackwell Publishing Ltd.
Web-based screening and brief intervention for the spectrum of alcohol problems.
Saitz, Richard; Helmuth, Eric D; Aromaa, Susan E; Guard, Anara; Belanger, Marc; Rosenbloom, David L
2004-11-01
Many persons who drink excessively remain unidentified and do not receive interventions. Screening and intervention using the World Wide Web could make such services more accessible and therefore more widely used. To evaluate the use of a novel alcohol screening and brief intervention Web site. A Web site was developed, posted, and its use was evaluated. We analyzed a sample of visitors who completed alcohol screening over a 14-month period to describe their alcohol use, and their use of portions of the Web site that provide information and referral resources. The Internet. Web site visitors, with a focus on visitors who completed an alcohol-screening questionnaire about their own drinking. Brief intervention via the Web site, consisting mainly of feedback, advice, and a menu of change options and referral information. Self-reported drinking amounts and alcohol screening test scores, and utilization of Web site components. Visitors completed online alcohol screening questionnaires at a rate of 50,711/year of 115,925 visitors/year. In a 14-month period, 39,842 adults completed the questionnaire about their own drinking habits; 66% were men, 90% reported drinking hazardous amounts (per occasion or typical weekly amounts), 88% reported binge (per occasion) drinking, and 55% reported typically exceeding weekly risky drinking limits. Most (65%) had alcohol screening test results (AUDIT > or = 8) consistent with alcohol abuse or dependence; similar proportions of women and men were hazardous drinkers. One-fifth of visitors visited portions of the Web site that provided additional information about alcohol use and referrals. Visitors with possible alcohol abuse or dependence were more likely than those without these disorders to visit a part of the Web site designed for those seeking additional help (33% vs. 8%, P < 0.0001). A well-publicized, easily accessible, research-based screening and intervention Web site can attract many users, most of whom are drinking excessively, and many of whom avail themselves of referral information after receiving individualized feedback.
Search for Screened Interactions Associated with Dark Energy below the 100 μm Length Scale.
Rider, Alexander D; Moore, David C; Blakemore, Charles P; Louis, Maxime; Lu, Marie; Gratta, Giorgio
2016-09-02
We present the results of a search for unknown interactions that couple to mass between an optically levitated microsphere and a gold-coated silicon cantilever. The scale and geometry of the apparatus enable a search for new forces that appear at distances below 100 μm and which would have evaded previous searches due to screening mechanisms. The data are consistent with electrostatic backgrounds and place upper limits on the strength of new interactions at <0.1 fN in the geometry tested. For the specific example of a chameleon interaction with an inverse power law potential, these results exclude matter couplings β>5.6×10^{4} in the region of parameter space where the self-coupling Λ≳5 meV and the microspheres are not fully screened.
2013-01-01
Background Autism spectrum disorder (ASD) can be difficult to distinguish from other psychiatric disorders. The clinical assessment of ASD is lengthy, and has to be performed by a specialized clinician. Therefore, a screening instrument to aid in the identification of patients who may have undiagnosed ASD should be useful. The purpose of this study was to develop such a screening instrument. Methods Based on the 80 item Ritvo Autism and Asperger Diagnostic Scale-Revised (RAADS-R), we developed a 14 item self-evaluation questionnaire, the RAADS-14 Screen. In total, 135 adults with ASD and 508 psychiatric controls completed the abridged version of the RAADS-R. Results The RAADS-14 Screen score was significantly higher in the ASD group than in the control samples, with a median score of 32 for ASD, 15 for attention deficit hyperactivity disorder, and 11 for other psychiatric disorders (P < 0.001). A cut-off score of 14 or above reached a sensitivity of 97% and a specificity of 46 to 64%. A factor analysis identified three factors consistent with mentalizing deficits, social anxiety, and sensory reactivity relevant for the diagnosis of ASD. The psychometric properties of RAADS-14 Screen were shown to be satisfactory. Conclusions The results of this study indicate that RAADS-14 Screen is a promising measure in screening for ASD in adult psychiatric outpatients. PMID:24321513
GW and Bethe-Salpeter study of small water clusters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Blase, Xavier, E-mail: xavier.blase@neel.cnrs.fr; Boulanger, Paul; Bruneval, Fabien
We study within the GW and Bethe-Salpeter many-body perturbation theories the electronic and optical properties of small (H{sub 2}O){sub n} water clusters (n = 1-6). Comparison with high-level CCSD(T) Coupled-Cluster at the Single Double (Triple) levels and ADC(3) Green’s function third order algebraic diagrammatic construction calculations indicates that the standard non-self-consistent G{sub 0}W{sub 0}@PBE or G{sub 0}W{sub 0}@PBE0 approaches significantly underestimate the ionization energy by about 1.1 eV and 0.5 eV, respectively. Consequently, the related Bethe-Salpeter lowest optical excitations are found to be located much too low in energy when building transitions from a non-self-consistent G{sub 0}W{sub 0} description ofmore » the quasiparticle spectrum. Simple self-consistent schemes, with update of the eigenvalues only, are shown to provide a weak dependence on the Kohn-Sham starting point and a much better agreement with reference calculations. The present findings rationalize the theory to experiment possible discrepancies observed in previous G{sub 0}W{sub 0} and Bethe-Salpeter studies of bulk water. The increase of the optical gap with increasing cluster size is consistent with the evolution from gas to dense ice or water phases and results from an enhanced screening of the electron-hole interaction.« less
Kaizer, Franceen; Kim, Angela; Van, My Tram; Korner-Bitensky, Nicol
2010-03-01
Patients with stroke should be screened for safety prior to starting a self-medication regime. An extensive literature review revealed no standardized self-medication tool tailored to the multi-faceted needs of the stroke population. The aim of this study was to create and validate a condition-specific tool to be used in screening for self-medication safety in individuals with stroke. Items were generated using expert consultation and review of the existing tools. The draft tool was pilot-tested on expert stroke clinicians to receive feedback on content, clarity, optimal cueing and domain omissions. The final version was piloted on patients with stroke using a structured interviewer-administered interview. The tool was progressively refined and validated according to feedback from the 11 expert reviewers. The subsequent version was piloted on patients with stroke. The final version includes 16 questions designed to elicit information on 5 domains: cognition, communication, motor, visual-perception and, judgement/executive function/self-efficacy. The Screening for Safe Self-medication post-Stroke Scale (S-5) has been created and validated for use by health professionals to screen self-medication safety readiness of patients after stroke. Its use should also help to guide clinicians' recommendations and interventions aimed at enhancing self-medication post-stroke.
Gu, Can; Chan, Carmen W H; Twinn, Sheila; Choi, Kai Chow
2012-12-01
Theories of health behavior and empirical research highlight the risk perception as a significant factor for people adopting cancer screening. However, screening uptakes and risk perception of cervical cancer in mainland Chinese women remains unknown. This paper adopted the protection motivation theory (PMT) to examine Chinese women's knowledge and perceptions of cervical cancer risk and factors influencing utilization of cervical screening. A self-administered questionnaire was completed by 167 participants in mainland China (79 nonscreened and 88 screened women) in 2007 which consisted of four sections: background information, women's attendance pattern for cervical screening, perceptions related to body health and knowledge about cervical cancer and screening, and PMT measures. All women considered themselves at low risk of cervical cancer. No significant association was observed between previous screening uptake and PMT variables. Using multivariate analysis, having children, a perception that visiting doctors regularly is important to health, average and high levels of knowledge about cervical screening were significantly associated with having been received screening. Chinese women demonstrated an unrealistic optimism about their personal risk of cervical cancer. The findings do not support an association between risk perception and screening uptake. In spite of this, current findings revealed some possible factors influencing women's screening behavior. This study highlights the significance of knowledge and culturally-relevant health behavior and beliefs about cervical screening for Chinese women in determining whether or not they receive screening. The promotion of cervical cancer prevention and early detection should be integrated into public education about women's health. Copyright © 2011 John Wiley & Sons, Ltd.
Penaranda, Eribeth; Molokwu, Jennifer; Hernandez, Ingrid; Salaiz, Rebekah; Nguyen, Norma; Byrd, Theresa; Shokar, Navkiran
2014-07-01
Hispanic women living along the US border with Mexico have one of the highest cervical cancer mortality rates in the nation, owing in part to lower rates of screening. The barriers to screening in this population include lack of access to care and fear of and embarrassment about the pelvic examination. Screening for oncogenic or high-risk human papillomavirus during cervical cytology has been added to screening recommendations. A novel method for human papillomavirus testing is self-sampling, in which women collect their own cervicovaginal samples. There is lack of information about the acceptability of self-sampling as an alternative to cytology for cervical cancer screening in women living along the US-Mexico border. We conducted five focus groups with women between the ages of 30 and 65 who were primary care patients of clinics along the US-Mexico border. We used constructs from different health behavioral theories as a framework for the interview guide. A total of 21 women participated in the focus groups, 80% of whom were Hispanic; mean age was 53.4 (standard deviation 7.9). More than one-third (38%) of the participants had not undergone a Papanicolaou test in the last 3 years. Women identified the perceived benefits of self-sampling as ease, convenience, practicability, less embarrassment, and need for child care as compared with a Papanicolaou test. The main barrier to self-sampling was concern about not performing the test correctly. In this qualitative study, we found positive attitudes toward self-sampling among women living along the US border with Mexico. Further research is needed to evaluate interventions that address women's low levels of self-efficacy to perform the test and to evaluate the effectiveness of self-sampling in increasing cervical cancer screening rates.
Munzer, Tiffany G; Miller, Alison L; Peterson, Karen E; Brophy-Herb, Holly E; Horodynski, Mildred A; Contreras, Dawn; Sturza, Julie; Lumeng, Julie C; Radesky, Jenny
2018-05-01
Excessive screen media exposure in childhood is associated with parent-reported self-regulation difficulties. No studies have used laboratory-based or teacher-reported measures of child self-regulatory behaviors. This study examines cross-sectional associations between preschooler screen media exposure and multiple measures of self-regulatory behaviors. Preintervention data were used from 541 preschoolers in the Growing Healthy study, an obesity prevention trial (2011-2015). Screen media exposure was measured by daily screen media exposure (hr/d), television (TV) in the bedroom, frequency of background TV, and TV with meals (1 = rarely/never, 4 = frequently). Child self-regulatory behaviors were measured by the following: child ability to delay gratification, a standardized waiting paradigm; teacher-reported Social Competence and Behavior Evaluation; and parent-reported difficult temperament on the Child Behavior Questionnaire (CBQ). Multivariate regression analyses modeled screen media exposure predicting each self-regulatory measure, adjusting for child age, sex, parent age, education, marital status, income-to-needs ratio, number of adults in household, parent depressive symptoms, and sensitivity. Children were aged 4.1 years (SD = 0.5), parents were aged 29.6 years (SD = 6.8), 48% had high school education or less, and 67% were married. Daily screen media exposure and background TV were associated with weaker observed self-regulation (β: -10.30 seconds for each hr/d media, -12.63 seconds for 1-point increase, respectively). Background TV and TV with meals were associated with greater parent-reported difficult temperament (β: 0.04 and 0.05 CBQ, respectively, for 1-point increase). Greater screen media exposure had small but significant associations with weaker observed and parent-reported, but not teacher-reported, self-regulatory behaviors. Longitudinal studies are needed to determine the directionality of associations.
Wave Propagation, Scattering and Imaging Using Dual-domain One-way and One-return Propagators
NASA Astrophysics Data System (ADS)
Wu, R.-S.
- Dual-domain one-way propagators implement wave propagation in heterogeneous media in mixed domains (space-wavenumber domains). One-way propagators neglect wave reverberations between heterogeneities but correctly handle the forward multiple-scattering including focusing/defocusing, diffraction, refraction and interference of waves. The algorithm shuttles between space-domain and wavenumber-domain using FFT, and the operations in the two domains are self-adaptive to the complexity of the media. The method makes the best use of the operations in each domain, resulting in efficient and accurate propagators. Due to recent progress, new versions of dual-domain methods overcame some limitations of the classical dual-domain methods (phase-screen or split-step Fourier methods) and can propagate large-angle waves quite accurately in media with strong velocity contrasts. These methods can deliver superior image quality (high resolution/high fidelity) for complex subsurface structures. One-way and one-return (De Wolf approximation) propagators can be also applied to wave-field modeling and simulations for some geophysical problems. In the article, a historical review and theoretical analysis of the Born, Rytov, and De Wolf approximations are given. A review on classical phase-screen or split-step Fourier methods is also given, followed by a summary and analysis of the new dual-domain propagators. The applications of the new propagators to seismic imaging and modeling are reviewed with several examples. For seismic imaging, the advantages and limitations of the traditional Kirchhoff migration and time-space domain finite-difference migration, when applied to 3-D complicated structures, are first analyzed. Then the special features, and applications of the new dual-domain methods are presented. Three versions of GSP (generalized screen propagators), the hybrid pseudo-screen, the wide-angle Padé-screen, and the higher-order generalized screen propagators are discussed. Recent progress also makes it possible to use the dual-domain propagators for modeling elastic reflections for complex structures and long-range propagations of crustal guided waves. Examples of 2-D and 3-D imaging and modeling using GSP methods are given.
Marcano-Belisario, José S; Gupta, Ajay K; O'Donoghue, John; Ramchandani, Paul; Morrison, Cecily; Car, Josip
2017-05-10
Mobile devices may facilitate depression screening in the waiting area of antenatal clinics. This can present implementation challenges, of which we focused on survey layout and technology deployment. We assessed the feasibility of using tablet computers to administer a socio-demographic survey, the Whooley questions and the Edinburgh Postnatal Depression Scale (EPDS) to 530 pregnant women attending National Health Service (NHS) antenatal clinics across England. We randomised participants to one of two layout versions of these surveys: (i) a scrolling layout where each survey was presented on a single screen; or (ii) a paging layout where only one question appeared on the screen at any given time. Overall, 85.10% of eligible pregnant women agreed to take part. Of these, 90.95% completed the study procedures. Approximately 23% of participants answered Yes to at least one Whooley question, and approximately 13% of them scored 10 points of more on the EPDS. We observed no association between survey layout and the responses given to the Whooley questions, the median EPDS scores, the number of participants at increased risk of self-harm, and the number of participants asking for technical assistance. However, we observed a difference in the number of participants at each EPDS scoring interval (p = 0.008), which provide an indication of a woman's risk of depression. A scrolling layout resulted in faster completion times (median = 4 min 46 s) than a paging layout (median = 5 min 33 s) (p = 0.024). However, the clinical significance of this difference (47.5 s) is yet to be determined. Tablet computers can be used for depression screening in the waiting area of antenatal clinics. This requires the careful consideration of clinical workflows, and technology-related issues such as connectivity and security. An association between survey layout and EPDS scoring intervals needs to be explored further to determine if it corresponds to a survey layout effect. Future research needs to evaluate the effect of this type of antenatal depression screening on clinical outcomes and clinic workflows. This study was registered in ClinicalTrials.gov under the identifier NCT02516982 on 20 July 2015.
Reese, Chad E; Asher, Sanford A
2002-04-01
We have developed emulsifier-free, emulsion polymerization recipes for the synthesis of highly charged, monodisperse latex particles of diameters between 500 and 1100 nm. These latexes consist of poly[styrene-(co-2-hydroxyethyl methacrylate)] spherical particles whose surfaces are functionalized with sulfate and carboxylic acid groups. These highly charged, monodisperse particles readily self-assemble into robust, three-dimensionally ordered crystalline colloidal array photonic crystals that Bragg diffract light in the near infrared spectral region. By altering the particle number density, the diffraction wavelength can be tuned from approximately 1000 to approximately 4000 nm.
A globally accurate theory for a class of binary mixture models
NASA Astrophysics Data System (ADS)
Dickman, Adriana G.; Stell, G.
The self-consistent Ornstein-Zernike approximation results for the 3D Ising model are used to obtain phase diagrams for binary mixtures described by decorated models, yielding the plait point, binodals, and closed-loop coexistence curves for the models proposed by Widom, Clark, Neece, and Wheeler. The results are in good agreement with series expansions and experiments.
[Utilization of self-sampling kits for HPV testing in cervical cancer screening - pilot study].
Ondryášová, H; Koudeláková, V; Drábek, J; Vaněk, P; Slavkovský, R; Hajdúch, M
2015-12-01
To get initial experience with alternative sampling (self-sampling) for HPV testing as the means of cervical cancer screening program. Original work. Institute of Molecular and Translational Medicine, Faculty of Medicine and Dentistry, Palacky University in Olomouc. Based on expression of interest, 215 self-sampling kits were posted to women. Evalyn(®) Brush Vaginal swabs obtained by self-sampling were analyzed for the presence of HPV infection by Cobas 4800 HPV (Roche) followed by genotyping using PapilloCheck(®) HPV-Screening (Greiner Bio-One). Sixty women randomly chosen from our sample were sent a questionnaire focused on their experience with self-sampling. One hundred seventy-four of 215 (81%) distributed self-sampling devices have been delivered to analysis. All cervicovaginal swabs were sampled correctly and it was possible to analyze them by Cobas 4800 HPV test. Similarly, 98% (171/174) samples were analyzable by PapilloCheck(®) HPV-Screening.One hundred twenty-five (72%) of 174 tested samples were HPV negative. Low risk HPV infection was detected only in 7 samples (4%), and high risk HPV (hrHPV) infection was present in 42 samples (24%). The most frequently detected hrHPV genotypes were HPV16 (11/42; 26%) and HPV53 (6/42; 14%). HrHPV co-infection was detected in 10 cases, in 5 of them lrHPV infection was find also.Of the 60 questionnaires, 48 (80%) were returned. From this group, 47 (98%) women rated their experience with self-sampling device as good to excellent. User manual of self-sampling device was considered good to excellent by all women (100%). All women also rated the convenience of self-sampling device using as good to excellent. As expected, most of the women (n = 42 [88%]) preferred self-sampling to physician sampling. Cervicovaginal self-sampling leads to valid results of HPV screening using two molecular genetics methods and was accepted by Czech women very well. The self-sampling as an opportunity to participate in cervical cancer screening could increase the attendance of the screening program and would help to reduce the incidence and mortality for this disease in the Czech population.
Linares, Mathieu; Stafström, Sven; Rinkevicius, Zilvinas; Ågren, Hans; Norman, Patrick
2011-05-12
A presentation of the complex polarization propagator in the restricted open-shell self-consistent field approximation is given. It rests on a formulation of a resonant-convergent, first-order polarization propagator approach that makes it possible to directly calculate the X-ray absorption cross section at a particular frequency without explicitly addressing the excited states. The quality of the predicted X-ray spectra relates only to the type of density functional applied without any separate treatment of dynamical relaxation effects. The method is applied to the calculation of the near K-edge X-ray absorption fine structure spectra of allyl and copper phthalocyanine. Comparison is made between the spectra of the radicals and those of the corresponding cations and anions to assess the effect of the increase of electron charge in the frontier orbital. The method offers the possibility for unique assignment of symmetry-independent atoms. The overall excellent spectral agreement motivates the application of the method as a routine precise tool for analyzing X-ray absorption of large systems of technological interest.
Development of FullWave : Hot Plasma RF Simulation Tool
NASA Astrophysics Data System (ADS)
Svidzinski, Vladimir; Kim, Jin-Soo; Spencer, J. Andrew; Zhao, Liangji; Galkin, Sergei
2017-10-01
Full wave simulation tool, modeling RF fields in hot inhomogeneous magnetized plasma, is being developed. The wave equations with linearized hot plasma dielectric response are solved in configuration space on adaptive cloud of computational points. The nonlocal hot plasma dielectric response is formulated in configuration space without limiting approximations by calculating the plasma conductivity kernel based on the solution of the linearized Vlasov equation in inhomogeneous magnetic field. This approach allows for better resolution of plasma resonances, antenna structures and complex boundaries. The formulation of FullWave and preliminary results will be presented: construction of the finite differences for approximation of derivatives on adaptive cloud of computational points; model and results of nonlocal conductivity kernel calculation in tokamak geometry; results of 2-D full wave simulations in the cold plasma model in tokamak geometry using the formulated approach; results of self-consistent calculations of hot plasma dielectric response and RF fields in 1-D mirror magnetic field; preliminary results of self-consistent simulations of 2-D RF fields in tokamak using the calculated hot plasma conductivity kernel; development of iterative solver for wave equations. Work is supported by the U.S. DOE SBIR program.
Correction factors for self-selection when evaluating screening programmes.
Spix, Claudia; Berthold, Frank; Hero, Barbara; Michaelis, Jörg; Schilling, Freimut H
2016-03-01
In screening programmes there is recognized bias introduced through participant self-selection (the healthy screenee bias). Methods used to evaluate screening programmes include Intention-to-screen, per-protocol, and the "post hoc" approach in which, after introducing screening for everyone, the only evaluation option is participants versus non-participants. All methods are prone to bias through self-selection. We present an overview of approaches to correct for this bias. We considered four methods to quantify and correct for self-selection bias. Simple calculations revealed that these corrections are actually all identical, and can be converted into each other. Based on this, correction factors for further situations and measures were derived. The application of these correction factors requires a number of assumptions. Using as an example the German Neuroblastoma Screening Study, no relevant reduction in mortality or stage 4 incidence due to screening was observed. The largest bias (in favour of screening) was observed when comparing participants with non-participants. Correcting for bias is particularly necessary when using the post hoc evaluation approach, however, in this situation not all required data are available. External data or further assumptions may be required for estimation. © The Author(s) 2015.
De Lepeleere, Sara; De Bourdeaudhuij, Ilse; Cardon, Greet; Verloigne, Maïté
2015-01-01
Objectives To assess the association between specific parenting practices and related parental self-efficacy with children's physical activity (PA) and screen time. Parental body mass index (BMI), family socioeconomic status (SES), and child's age and gender were examined as possible influencing factors. Design Cross-sectional. Setting January 2014, Flanders (Belgium). Participants 207 parents (87.4% mothers) of children aged 6–12 years. Outcome measures Specific parenting practices, related parental self-efficacy, and children's PA and screen time. Results The majority of investigated parenting practices and related parental self-efficacy were not significantly associated with children's PA or screen time. However, children were more physically active if sports equipment was available at home (p<0.10) and if parents did not find it difficult to motivate their child to be physically active (p<0.05). Children had a lower screen time if parents limited their own gaming (p<0.01). The associations between parenting practices and related parental self-efficacy with children's PA or screen time were significant for parents with a normal BMI, for medium-high SES families and for parents of younger children. Furthermore, the association between the parenting relating factors and children's PA and screen time differed for boys and girls. Conclusions In contrast to what we expected, the findings of the current study show that only a very few specific parenting practices and related parental self-efficacy were associated with children's PA and screen time. It was expected that parental self-efficacy would play a more important role. This can be due to the fact that parental self-efficacy was already high in this group of parents. Therefore, it is possible that parents do not realise how difficult it is to perform certain parenting practices until they are faced with it in an intervention. Trial registration number EC/2012/317. PMID:26346871
Cadman, Louise; Wilkes, Scott; Mansour, Diana; Austin, Janet; Ashdown-Barr, Lesley; Edwards, Rob; Kleeman, Michelle; Szarewski, Anne
2015-03-01
Non-attenders for cervical screening are at increased risk of cervical cancer. Studies offering self-sampling for high-risk Human Papillomavirus (HrHPV) testing have shown greater uptake than sending another invitation for cytology. To explore whether uptake would increase in a less diverse, more stable population than the previous English study, which demonstrated a lower response rate than other studies. The primary objective was whether non-attenders were more likely to respond to a postal invitation, including kit, to collect a self-sample compared with a further invitation for cytology screening. The secondary objective was whether women with an abnormal result would attend for follow-up. 6000 non-attenders for screening in this pragmatic, randomized (1:1) controlled trial in Newcastle-upon-Tyne were sent an HPV self-sample kit (intervention) or a further invitation for cytology screening (comparator). 411(13%) responded to the intervention, returning a self-sample (247(8%)) or attending for cytology (164(5%)), compared with 183(6%) attending for cytology, relative risk 2.25 (95% CI 1.90-2.65) (comparator arm). Of those testing hrHPV positive (32(13%)), 19(59%) subsequently attended cytology screening. Of those in the intervention group who attended for cytology screening without returning an hrHPV self-sample (n = 164), 5% (n = 8) were referred for colposcopy - all attended. In the comparator group eight of the nine referred for colposcopy attended. Persistent non-responders to invitations for cervical screening are significantly more likely to respond to a postal invitation to return a self-collected sample for HPV testing than a further invitation for cytology screening. However, just over half followed up on this positive HPV result. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
LaPlante, Laura Marie; Gopalan, Priya; Glance, Jody
2016-10-01
This study aims to assess residents' attitudes, knowledge, practices, and barriers in addressing intimate partner violence and create a curriculum targeting self-identified deficits. The authors developed and distributed a survey to residents across multiple specialties at a large academic institution. A workshop was developed using obstetrics/gynecology residents' data, with post-intervention data collected to assess for changes. One hundred forty-seven residents (41 %) completed the survey. Though all identified assessing intimate partner violence as physicians' responsibility, only 40 % reported consistent screening with new female patients, 36 % with pregnant patients, and 18 % with post-partum patients. Half reported inadequate training and felt unprepared to counsel patients regarding intimate partner violence. Post-intervention data suggest gains in knowledge and perceived preparedness. Although residents appreciate the significance of intimate partner violence assessment, in this particular institution few consistently perform or feel comfortable screening. Development of comprehensive intimate partner violence curricula is therefore critical.
Luttinger theorem and imbalanced Fermi systems
NASA Astrophysics Data System (ADS)
Pieri, Pierbiagio; Strinati, Giancarlo Calvanese
2017-04-01
The proof of the Luttinger theorem, which was originally given for a normal Fermi liquid with equal spin populations formally described by the exact many-body theory at zero temperature, is here extended to an approximate theory given in terms of a "conserving" approximation also with spin imbalanced populations. The need for this extended proof, whose underlying assumptions are here spelled out in detail, stems from the recent interest in superfluid trapped Fermi atoms with attractive inter-particle interaction, for which the difference between two spin populations can be made large enough that superfluidity is destroyed and the system remains normal even at zero temperature. In this context, we will demonstrate the validity of the Luttinger theorem separately for the two spin populations for any "Φ-derivable" approximation, and illustrate it in particular for the self-consistent t-matrix approximation.
Average size of random polygons with fixed knot topology.
Matsuda, Hiroshi; Yao, Akihisa; Tsukahara, Hiroshi; Deguchi, Tetsuo; Furuta, Ko; Inami, Takeo
2003-07-01
We have evaluated by numerical simulation the average size R(K) of random polygons of fixed knot topology K=,3(1),3(1) musical sharp 4(1), and we have confirmed the scaling law R(2)(K) approximately N(2nu(K)) for the number N of polygonal nodes in a wide range; N=100-2200. The best fit gives 2nu(K) approximately 1.11-1.16 with good fitting curves in the whole range of N. The estimate of 2nu(K) is consistent with the exponent of self-avoiding polygons. In a limited range of N (N greater, similar 600), however, we have another fit with 2nu(K) approximately 1.01-1.07, which is close to the exponent of random polygons.
NASA Astrophysics Data System (ADS)
Tselyaev, V.; Lyutorovich, N.; Speth, J.; Krewald, S.; Reinhard, P.-G.
2016-09-01
We present results of the time blocking approximation (TBA) for giant resonances in light-, medium-, and heavy-mass nuclei. The TBA is an extension of the widely used random-phase approximation (RPA) adding complex configurations by coupling to phonon excitations. A new method for handling the single-particle continuum is developed and applied in the present calculations. We investigate in detail the dependence of the numerical results on the size of the single-particle space and the number of phonons as well as on nuclear matter properties. Our approach is self-consistent, based on an energy-density functional of Skyrme type where we used seven different parameter sets. The numerical results are compared with experimental data.
Sasaki, Ryo; Angelaki, Dora E; DeAngelis, Gregory C
2017-11-15
We use visual image motion to judge the movement of objects, as well as our own movements through the environment. Generally, image motion components caused by object motion and self-motion are confounded in the retinal image. Thus, to estimate heading, the brain would ideally marginalize out the effects of object motion (or vice versa), but little is known about how this is accomplished neurally. Behavioral studies suggest that vestibular signals play a role in dissociating object motion and self-motion, and recent computational work suggests that a linear decoder can approximate marginalization by taking advantage of diverse multisensory representations. By measuring responses of MSTd neurons in two male rhesus monkeys and by applying a recently-developed method to approximate marginalization by linear population decoding, we tested the hypothesis that vestibular signals help to dissociate self-motion and object motion. We show that vestibular signals stabilize tuning for heading in neurons with congruent visual and vestibular heading preferences, whereas they stabilize tuning for object motion in neurons with discrepant preferences. Thus, vestibular signals enhance the separability of joint tuning for object motion and self-motion. We further show that a linear decoder, designed to approximate marginalization, allows the population to represent either self-motion or object motion with good accuracy. Decoder weights are broadly consistent with a readout strategy, suggested by recent computational work, in which responses are decoded according to the vestibular preferences of multisensory neurons. These results demonstrate, at both single neuron and population levels, that vestibular signals help to dissociate self-motion and object motion. SIGNIFICANCE STATEMENT The brain often needs to estimate one property of a changing environment while ignoring others. This can be difficult because multiple properties of the environment may be confounded in sensory signals. The brain can solve this problem by marginalizing over irrelevant properties to estimate the property-of-interest. We explore this problem in the context of self-motion and object motion, which are inherently confounded in the retinal image. We examine how diversity in a population of multisensory neurons may be exploited to decode self-motion and object motion from the population activity of neurons in macaque area MSTd. Copyright © 2017 the authors 0270-6474/17/3711204-16$15.00/0.
Mutters, N T; Günther, F; Frank, U; Mischnik, A
2016-06-01
Multidrug-resistant organisms (MDROs) are an economic burden, and infection control (IC) measures are cost- and labour-intensive. A two-tier IC management strategy was developed, including active screening, in order to achieve effective use of limited resources. Briefly, high-risk patients were differentiated from other patients, distinguished according to type of MDRO, and IC measures were implemented accordingly. To evaluate costs and benefits of this IC management strategy. The study period comprised 2.5 years. All high-risk patients underwent microbiological screening. Gram-negative bacteria (GNB) were classified as multidrug-resistant (MDR) and extensively drug-resistant (XDR). Expenses consisted of costs for staff, materials, laboratory, increased workload and occupational costs. In total, 39,551 patients were screened, accounting for 24.5% of all admissions. Of all screened patients, 7.8% (N=3,104) were MDRO positive; these patients were mainly colonized with vancomycin-resistant enterococci (37.3%), followed by meticillin-resistant Staphylococcus aureus (30.3%) and MDR-GNB (28.3%). The median length of stay (LOS) for all patients was 10 days (interquartile range 3-20); LOS was twice as long in colonized patients (P<0.001). Screening costs totalled 255,093.82€, IC measures cost 97,701.36€, and opportunity costs were 599,225.52€. The savings of this IC management strategy totalled 500,941.84€. Possible transmissions by undetected carriers would have caused additional costs of 613,648.90-4,974,939.26€ (i.e. approximately 600,000-5 million €). Although the costs of a two-tier IC management strategy including active microbiological screening are not trivial, these data indicate that the approach is cost-effective when prevented transmissions are included in the cost estimate. Copyright © 2016 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.
Schram, Patricia; Harris, Sion K; Van Hook, Shari; Forman, Sara; Mezzacappa, Enrico; Pavlyuk, Roman; Levy, Sharon
2015-01-01
Screening, brief intervention, and referral to treatment (SBIRT) is recommended as part of routine health care for adolescents as well as adults. In an effort to promote universal SBIRT, the Substance Abuse and Mental Health Services Administration awarded funding to residency programs to develop and implement SBIRT education and training. Our project focused on creating scientifically based, developmentally appropriate strategies and teaching materials for the adolescent age range. This paper describes curriculum development and implementation and presents evaluation data. Pediatric and child psychiatry residents were trained. The training consisted of 4 activities: (1) case-based teaching modules, (2) role-play of motivational interviewing and brief interventions, (3) mock interviews with trained adolescents, and (4) supervised "hands-on" screening and brief interventions. Main outcome measures included trainee satisfaction, and SBIRT knowledge, perceived self-efficacy, and self- and observer report of use of the SBIRT algorithm. Among 150 total participants completing the SBIRT training modules, nearly all (92.3%) were satisfied/very satisfied with the training modules. Knowledge accuracy immediately post training was high, but declined significantly by the end of the first residency year, with little change across subsequent years of residency. Confidence ratings also declined over time. Use of the SBIRT algorithm during the Adolescent Medicine rotation was high according to trainee self- and faculty observer report. We found evidence of training satisfaction, increased confidence in talking to adolescents about substance use, and widespread use of recommended practices immediately following training. Use of a highly structured algorithm to guide practice, and simple, highly structured brief interventions was a successful training approach, as residents self-reported accurate use of the SBIRT algorithm immediately after training. Knowledge and self-confidence declined over time. It is possible that "booster" sessions and ongoing opportunities to review materials could help residents retain knowledge and skills.
Gual, Pilar; Pérez-Gaspar, Marta; Martínez-González, Miguel Angel; Lahortiga, Francisca; de Irala-Estévez, Jokin; Cervera-Enguix, Salvador
2002-04-01
To study the relationship of self-esteem and personality factors with eating disorders (ED). A region-wide representative sample of 2862 girls 12-21 years old from Navarre (Spain) participated in the baseline assessment of a prospective study. A two-stage procedure was used, consisting in a first screening phase followed by a psychiatrist interview (DSM-IV criteria). Multivariable logistic regression models were used to examine the association of self-esteem (36-item scale) and personality characteristics (Eysenck inventory) with psychiatrist-diagnosed ED while controlling for potential confounders. Strong associations for ED were found with low self-esteem (adjusted odds ratio [adjOR] for the lowest quartile: 7.98, 95% CI: 3.4-18.8) and high levels of neuroticism (adjOR for the highest quartile: 9.49, 95% Cl: 3.7-24.5). Our results, although based on a cross-sectional design, support the potential role of neuroticism and low self-esteem in the onset of ED. Copyright 2002 by Wiley Periodicals, Inc.
Predictive simulations and optimization of nanowire field-effect PSA sensors including screening
NASA Astrophysics Data System (ADS)
Baumgartner, Stefan; Heitzinger, Clemens; Vacic, Aleksandar; Reed, Mark A.
2013-06-01
We apply our self-consistent PDE model for the electrical response of field-effect sensors to the 3D simulation of nanowire PSA (prostate-specific antigen) sensors. The charge concentration in the biofunctionalized boundary layer at the semiconductor-electrolyte interface is calculated using the propka algorithm, and the screening of the biomolecules by the free ions in the liquid is modeled by a sensitivity factor. This comprehensive approach yields excellent agreement with experimental current-voltage characteristics without any fitting parameters. Having verified the numerical model in this manner, we study the sensitivity of nanowire PSA sensors by changing device parameters, making it possible to optimize the devices and revealing the attributes of the optimal field-effect sensor.
Harris, Sion Kim; Knight, John R; Van Hook, Shari; Sherritt, Lon; Brooks, Traci; Kulig, John W; Nordt, Christina; Saitz, Richard
2015-01-01
Background Computer self-administration may help busy pediatricians’ offices increase adolescent substance use screening rates efficiently and effectively, if proven to yield valid responses. The CRAFFT screening protocol for adolescents has demonstrated validity as an interview, but a computer self-entry approach needs validity testing. The aim of this study was to evaluate the criterion validity and time efficiency of a computerized adolescent substance use screening protocol implemented by self-administration or clinician-administration. Methods 12- to 17-year-old patients coming for routine care at three primary care clinics completed the computerized screen by both self-administration and clinician-administration during their visit. To account for order effects, we randomly assigned participants to self-administer the screen either before or after seeing their clinician. Both were conducted using a tablet computer and included identical items (any past-12-month use of tobacco, alcohol, drugs; past-3-months frequency of each; and six CRAFFT items). The criterion measure for substance use was the Timeline Follow-Back, and for alcohol/drug use disorder, the Adolescent Diagnostic Interview, both conducted by confidential research assistant-interview after the visit. Tobacco dependence risk was assessed with the self-administered Hooked on Nicotine Checklist (HONC). Analyses accounted for the multi-site cluster sampling design. Results Among 136 participants, mean age was 15.0±1.5 yrs, 54% were girls, 53% were Black or Hispanic, and 67% had ≥3 prior visits with their clinician. Twenty-seven percent reported any substance use (including tobacco) in the past 12 months, 7% met criteria for an alcohol or cannabis use disorder, and 4% were HONC-positive. Sensitivity/specificity of the screener were high for detecting past-12-month use or disorder and did not differ between computer and clinician. Mean completion time was 49 seconds (95%CI 44-54) for computer and 74 seconds (95%CI 68-87) for clinician (paired comparison p<0.001). Conclusions Substance use screening by computer self-entry is a valid and time-efficient alternative to clinician-administered screening. PMID:25774878
The influence of time perspective on cervical cancer screening among Latinas in the United States.
Roncancio, Angelica M; Ward, Kristy K; Fernandez, Maria E
2014-12-01
To develop effective interventions to increase cervical cancer screening among Latinas, we should understand the role of cultural factors, such as time perspective, in the decision to be screened. We examined the relation between present time orientation, future time orientation, and self-reported cervical cancer screening among Latinas. A group of 206 Latinas completed a survey measuring factors associated with screening. Logistic regression analyses revealed that future time orientation was significantly associated with self-reported screening. Understanding the influence of time orientation on cervical cancer screening will assist us in developing interventions that effectively target time perspective and screening. © The Author(s) 2013.
Production and characterization of tearless and non-pungent onion.
Kato, Masahiro; Masamura, Noriya; Shono, Jinji; Okamoto, Daisaku; Abe, Tomoko; Imai, Shinsuke
2016-04-06
The onion lachrymatory factor (LF) is produced from trans-S-1-propenyl-L-cysteine sulfoxide (PRENCSO) through successive reactions catalyzed by alliinase (EC 4.4.1.4) and lachrymatory factor synthase (LFS), and is responsible for the tear inducing-property and the pungency of fresh onions. We developed tearless, non-pungent onions non-transgenically by irradiating seeds with neon-ion at 20 Gy. The bulbs obtained from the irradiated seeds and their offspring bulbs produced by selfing were screened by organoleptic assessment of tear-inducing property or HPLC analysis of LF production. After repeated screening and seed production by selfing, two tearless, non-pungent bulbs were identified in the third generation (M3) bulbs. Twenty M4 bulbs obtained from each of them showed no tear-inducing property or pungency when evaluated by 20 sensory panelists. The LF production levels in these bulbs were approximately 7.5-fold lower than those of the normal onion. The low LF production levels were due to reduction in alliinase activity, which was a result of low alliinase mRNA expression (less than 1% of that in the normal onion) and consequent low amounts of the alliinase protein. These tearless, non-pungent onions should be welcomed by all who tear while chopping onions and those who work in facilities where fresh onions are processed.
NASA Astrophysics Data System (ADS)
Schulthess, T.; Monnier, R.; Crampin, S.
1994-12-01
First-principles results are presented for the effective cluster interactions at the surface of a random Ni-10 at. % Al alloy. The derivation is based on an extension of the generalized perturbation method to semi-infinite inhomogeneous binary alloys, using a layer version of the Korringa-Kohn-Rostocker multiple-scattering approach in conjunction with the single-site coherent potential approximation to compute the self-consistent electronic structure of the system. When applied to the bulk, the method yields effective pair interactions that have the full point-group symmetry of the lattice to a very high level of numerical accuracy, despite the fact that intra- and interlayer couplings (scattering-path operators) are treated differently, and which are in perfect agreement with those of a recent three-dimensional treatment. Besides the pair terms, a selected class of triplet and quadruplet interactions are calculated, as well as the point interactions induced by the presence of the surface. The value of the latter in the first lattice plane is strongly exaggerated in our approach, leading to a complete segregation of the minority species to the surface. Using a value corresponding to the difference in the surface energies of the pure components for this term leads to the observed Al concentration of ~=25% at the surface. Possible reasons for the shortcomings of the theory are analyzed, and test calculations for the well studied Cu-Ni system show that the free energy of the semi-infinite alloy cannot be approximated by the sum over the single-particle band energies, once charge self-consistency is enforced at the surface.
Jupiter, Tina
2009-12-01
To determine whether distortion product otoacoustic emissions (DPOAEs) could be used as a hearing screening tool with elderly individuals living independently, and to compare the utility of different screening protocols: (a) 3 pure-tone screening protocols consisting of 30 dB HL at 1, 2, and 3 kHz; 40 dB HL at 1, 2, and 3 kHz; or 40 dB HL at 1 and 2 kHz; (b) the Hearing Handicap Inventory for the Elderly-Screening version (HHIE-S); (c) pure tones at 40 dB HL at 1 and 2 kHz plus the HHIE-S; and (d) DPOAEs. A total of 106 elderly individuals age 65-91 years were screened using the above protocols. Pass/fail results showed that most individuals failed at 30 dB HL, followed by DPOAEs, the 40-dB HL protocols, the HHIE-S alone, and the combined pure-tone/HHIE-S protocol. All screening results were associated except the HHIE-S and 30 dB HL and the HHIE-S and DPOAEs. A McNemar analysis revealed that the differences between the correlated pass/fail results were significant except for the HHIE-S and 40 dB at 1 and 2 kHz. DPOAEs can be used to screen the elderly, with the advantage that individuals do not have to voluntarily respond to the test.
Exploring the acceptability of human papillomavirus self-sampling among Muslim immigrant women.
Lofters, Aisha K; Vahabi, Mandana; Fardad, Mitra; Raza, Afrah
2017-01-01
With appropriate screening (ie, the Papanicolaou [Pap] test), cervical cancer is highly preventable, and high-income countries, including Canada, have observed significant decreases in cervical cancer mortality. However, certain subgroups, including immigrants from countries with large Muslim populations, experience disparities in cervical cancer screening. Little is known about the acceptability of human papillomavirus (HPV) self-sampling as a screening strategy among Muslim immigrant women in Canada. This study assessed cervical cancer screening practices, knowledge and attitudes, and acceptability of HPV self-sampling among Muslim immigrant women. A convenience sample of 30 women was recruited over a 3-month period (June-August 2015) in the Greater Toronto Area. All women were between 21 and 69 years old, foreign-born, and self-identified as Muslim, and had good knowledge of English. Data were collected through a self-completed questionnaire. More than half of the participants falsely indicated that Pap tests may cause cervical infection, and 46.7% indicated that the test is an intrusion on privacy. The majority of women reported that they would be willing to try HPV self-sampling, and more than half would prefer this method to provider-administered sampling methods. Barriers to self-sampling included confidence in the ability to perform the test and perceived cost, and facilitators included convenience and privacy being preserved. The results demonstrate that HPV self-sampling may provide a favorable alternative model of care to the traditional provider-administered Pap testing. These findings add important information to the literature related to promoting cancer screening among women who are under or never screened for cervical cancer.
Ayral, Thomas; Vučičević, Jaksa; Parcollet, Olivier
2017-10-20
We present an embedded-cluster method, based on the triply irreducible local expansion formalism. It turns the Fierz ambiguity, inherent to approaches based on a bosonic decoupling of local fermionic interactions, into a convergence criterion. It is based on the approximation of the three-leg vertex by a coarse-grained vertex computed from a self-consistently determined cluster impurity model. The computed self-energies are, by construction, continuous functions of momentum. We show that, in three interaction and doping regimes of the two-dimensional Hubbard model, self-energies obtained with clusters of size four only are very close to numerically exact benchmark results. We show that the Fierz parameter, which parametrizes the freedom in the Hubbard-Stratonovich decoupling, can be used as a quality control parameter. By contrast, the GW+extended dynamical mean field theory approximation with four cluster sites is shown to yield good results only in the weak-coupling regime and for a particular decoupling. Finally, we show that the vertex has spatially nonlocal components only at low Matsubara frequencies.
Lipkus, Isaac M; Scholl, Sarah; McQueen, Amy; Cerully, Jennifer; Harris, Peter R
2009-01-01
We examined whether self-affirmation would facilitate intentions to engage in colorectal cancer (CRC) screening among individuals who were off-schedule for CRC screening and who were categorized as unrealistically optimistic, realistic, or unrealistically pessimistic about their CRC risk. All participants received tailored risk feedback; in addition, one group received threatening social comparison information regarding their risk factors, a second received this information after a self-affirmation exercise, and a third was a no-treatment control. When participants were unrealistically optimistic about their CRC risk (determined by comparing their perceived comparative risk to calculations from a risk algorithm), they expressed greater interest in screening if they were self-affirmed (relative to controls). Non-affirmed unrealistic optimists expressed lower interest relative to controls, suggesting that they were responding defensively. Realistic participants and unrealistically pessimistic participants who were self-affirmed expressed relatively less interest in CRC screening, suggesting that self-affirmation can be helpful or hurtful depending on the accuracy of one’s risk perceptions. PMID:20204982
NASA Astrophysics Data System (ADS)
Sahni, V.; Ma, C. Q.
1980-12-01
The inhomogeneous electron gas at a jellium metal surface is studied in the Hartree-Fock approximation by Kohn-Sham density functional theory. Rigorous upper bounds to the surface energy are derived by application of the Rayleigh-Ritz variational principle for the energy, the surface kinetic, electrostatic, and nonlocal exchange energy functionals being determined exactly for the accurate linear-potential model electronic wave functions. The densities obtained by the energy minimization constraint are then employed to determine work-function results via the variationally accurate "displaced-profile change-in-self-consistent-field" expression. The theoretical basis of this non-self-consistent procedure and its demonstrated accuracy for the fully correlated system (as treated within the local-density approximation for exchange and correlation) leads us to conclude these results for the surface energies and work functions to be essentially exact. Work-function values are also determined by the Koopmans'-theorem expression, both for these densities as well as for those obtained by satisfaction of the constraint set on the electrostatic potential by the Budd-Vannimenus theorem. The use of the Hartree-Fock results in the accurate estimation of correlation-effect contributions to these surface properties of the nonuniform electron gas is also indicated. In addition, the original work and approximations made by Bardeen in this attempt at a solution of the Hartree-Fock problem are briefly reviewed in order to contrast with the present work.
Lofters, A K; Slater, M; Vahabi, M
2018-02-01
Cancer screening is a core component of family medicine but screening inequalities are well documented in Canada for foreign-born persons. Although people of Muslim faith and culture are the fastest growing immigrant population in Canada, there is little information in the literature about their cancer screening practices. Determining screening gaps could inform practice-based quality improvement initiatives. We conducted a retrospective chart review combining patient-level medical record data with self-reported religious affiliation to examine the relationship between religion and cancer screening in a large multi-site urban family practice. Religious affiliation was classified as Muslim, other affiliation, or atheist/no religious affiliation. 5311 patients were included in the study sample. Muslim patients were significantly less likely to prefer English for spoken communication than the other two groups, less likely to be Canadian-born, more likely to have a female family physician, and were over-represented in the lowest income quintile. Muslim women were most likely to be up-to-date on breast cancer screening (85.2 vs. 77.5 % for those with other religions vs. 69.5 % for those with no religious affiliation). There were no significant differences in cancer screening by physician sex. In this pilot study conducted within a primary care practice, we used self-reported data on religious affiliation to examine possible inequities in cancer screening and observed intriguing variations in screening by self-identified religious affiliation. Future efforts to collect and use similar patient-level data should incorporate non-official languages and intensively outreach to patients with less health system contact. Regardless, the family medicine context may be the ideal setting to collect and act on patient-level sociodemographic data such as religious affiliation.
2-D Modeling of Nanoscale MOSFETs: Non-Equilibrium Green's Function Approach
NASA Technical Reports Server (NTRS)
Svizhenko, Alexei; Anantram, M. P.; Govindan, T. R.; Biegel, Bryan
2001-01-01
We have developed physical approximations and computer code capable of realistically simulating 2-D nanoscale transistors, using the non-equilibrium Green's function (NEGF) method. This is the most accurate full quantum model yet applied to 2-D device simulation. Open boundary conditions and oxide tunneling are treated on an equal footing. Electrons in the ellipsoids of the conduction band are treated within the anisotropic effective mass approximation. Electron-electron interaction is treated within Hartree approximation by solving NEGF and Poisson equations self-consistently. For the calculations presented here, parallelization is performed by distributing the solution of NEGF equations to various processors, energy wise. We present simulation of the "benchmark" MIT 25nm and 90nm MOSFETs and compare our results to those from the drift-diffusion simulator and the quantum-corrected results available. In the 25nm MOSFET, the channel length is less than ten times the electron wavelength, and the electron scattering time is comparable to its transit time. Our main results are: (1) Simulated drain subthreshold current characteristics are shown, where the potential profiles are calculated self-consistently by the corresponding simulation methods. The current predicted by our quantum simulation has smaller subthreshold slope of the Vg dependence which results in higher threshold voltage. (2) When gate oxide thickness is less than 2 nm, gate oxide leakage is a primary factor which determines off-current of a MOSFET (3) Using our 2-D NEGF simulator, we found several ways to drastically decrease oxide leakage current without compromising drive current. (4) Quantum mechanically calculated electron density is much smaller than the background doping density in the poly silicon gate region near oxide interface. This creates an additional effective gate voltage. Different ways to. include this effect approximately will be discussed.
Guichard, Elie; Kurth, Tobias
2016-01-01
Objective To investigate whether high levels of screen time exposure are associated with self-perceived levels of attention problems and hyperactivity in higher education students. Design Cross-sectional study among participants of the i-Share cohort. Setting French-speaking students of universities and higher education institutions. Participants 4816 graduate students who were at least 18 years old. Exposure Screen time was assessed by self-report of the average time spent on five different screen activities on smartphone, television, computer and tablet and categorised into quartiles. Main outcome measure We used the Attention Deficit Hyperactivity Disorder Self-Report Scale (ASRS-v1.1) concerning students’ behaviour over the past 6 months to measure self-perceived levels of attention problems and hyperactivity. Responses were summarised into a global score as well as scores for attention problems and hyperactivity. Results The 4816 participants of this study had a mean age of 20.8 years and 75.5% were female. Multivariable ordinary regression models showed significant associations of screen time exposure with quintiles of the total score of self-perceived attention problems and hyperactivity levels as well as the individual domains. Compared to the lowest screen time exposure category, the ORs (95% CI) were 1.58 (1.37 to 1.82) for each increasing level of quintiles of the global score, 1.57 (1.36 to 1.81) for increasing quintiles of attention levels and 1.25 (1.09 to 1.44) for increasing quartiles of hyperactivity. Conclusions Results of this large cross-sectional study among French university and higher education students show dose-dependent associations between screen time and self-perceived levels of attention problems and hyperactivity. Further studies are warranted to evaluate whether interventions could positively influence these associations. PMID:26920440
Matin, Nassim; Kelishadi, Roya; Heshmat, Ramin; Motamed-Gorji, Nazgol; Djalalinia, Shirin; Motlagh, Mohammad Esmaeil; Ardalan, Gelayol; Arefirad, Tahereh; Mohammadi, Rasool; Safiri, Saeid; Qorbani, Mostafa
2017-01-01
Self-rated health and life satisfaction are two subjective measures for assessing overall health status. This study aims to investigate the association of self-rated health and life satisfaction with physical activity and screen time. As part of the fourth survey of a national surveillance program in Iran (CASPIAN-IV study), 14 880 students aged 6 to 18 years were selected via multi-stage cluster sampling from 30 provinces. Data were obtained from the WHO Global School-Based Student Health Survey questionnaire. A total of 13 486 students with mean age of 12.47 (SD 3.36) completed the study. In crude model both prolonged screen time and physical activity were associated with favorable life satisfaction and self-rated health. However, in multivariate analysis only high physical activity was associated with good self-rated health (OR 1.37) and life satisfaction (OR 1.39), while prolonged screen time was not associated with good self-rated health (OR 1.02) and life satisfaction (OR 0.94). For combined screen time-physical activity variable, low screen time-high physical activity combination had the highest OR for both good self-rated health (OR 1.37) and life satisfaction (OR 1.43) in multivariate analysis. Our findings suggest that increasing physical activity is more crucial than emphasizing reducing screen time in improving the well-being of children and adolescents. © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Aprea, Giuseppe; Mullan, William Michael; Murru, Nicoletta; Fitzgerald, Gerald; Buonanno, Marialuisa; Cortesi, Maria Luisa; Prencipe, Vincenza Annunziata; Migliorati, Giacomo
2017-09-30
This work investigated bacteriophage induced starter failures in artisanal buffalo Mozzarella production plants in Southern Italy. Two hundred and ten samples of whey starter cultures were screened for bacteriophage infection. Multiplex polymerase chain reaction (PCR) revealed phage infection in 28.56% of samples, all showing acidification problems during cheese making. Based on DNA sequences, bacteriophages for Lactococcus lactis (L. lactis), Lactobacillus delbruekii (L. delbruekii) and Streptococcus thermophilus (S. thermophilus) were detected. Two phages active against L. lactis, ΦApr-1 and ΦApr-2, were isolated and characterised. The genomes, approximately 31.4 kb and 31 kb for ΦApr-1 and ΦApr-2 respectively, consisted of double-stranded linear DNA with pac-type system. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‑PAGE) showed one major structural protein of approximately 32.5 kDa and several minor proteins. This is the first report of phage isolation in buffalo milk and of the use of multiplex PCR to screen and study the diversity of phages against Lactic Acid Bacteria (LAB) strains in artisanal Water Buffalo Mozzarella starters.
Storm time plasma transport in a unified and inter-coupled global magnetosphere model
NASA Astrophysics Data System (ADS)
Ilie, R.; Liemohn, M. W.; Toth, G.
2014-12-01
We present results from the two-way self-consistent coupling between the kinetic Hot Electron and Ion Drift Integrator (HEIDI) model and the Space Weather Modeling Framework (SWMF). HEIDI solves the time dependent, gyration and bounced averaged kinetic equation for the phase space density of different ring current species and computes full pitch angle distributions for all local times and radial distances. During geomagnetic times the dipole approximation becomes unsuitable even in the inner magnetosphere. Therefore the HEIDI model was generalized to accommodate an arbitrary magnetic field and through the coupling with SWMF it obtains a magnetic field description throughout the HEIDI domain along with a plasma distribution at the model outer boundary from the Block Adaptive Tree Solar Wind Roe Upwind Scheme (BATS-R-US) magnetohydrodynamics (MHD) model within SWMF. Electric field self-consistency is assured by the passing of convection potentials from the Ridley Ionosphere Model (RIM) within SWMF. In this study we test the various levels of coupling between the 3 physics based models, highlighting the role that the magnetic field, plasma sheet conditions and the cross polar cap potential play in the formation and evolution of the ring current. We show that the dynamically changing geospace environment itself plays a key role in determining the geoeffectiveness of the driver. The results of the self-consistent coupling between HEIDI, BATS-R-US and RIM during disturbed conditions emphasize the importance of a kinetic self-consistent approach to the description of geospace.
Reproducibility of self-reported pap test utilization in middle-aged African-American women.
Hoyo, Cathrine; Ostbye, Truls; Skinner, Celette S; Yarnall, Kimberly S H; Chowdhary, Jaspreet
2005-01-01
Both clinicians who perform Pap tests and prescribe re-screens and public health officials, who periodically evaluate the success of Pap test screening programs, often depend on women to self-report their most recent Pap test. However, reliability of self-reported Pap test utilization is putatively low, and even lower in African-American women compared to Whites. Between 2001 and 2002, Pap test screening histories were obtained from 144 African-American women, aged 45 to 64 years at two in-person interviews conducted three to six weeks apart. Reproducibility of self-reported Pap test was substantial (kappa=0.64; 95% confidence interval: .46-.82), with the highest agreement among women with greater income and educational attainment, and those who were younger. This level of reproducibility is likely sufficient both to evaluate the population coverage of public health screening programs and for prescribing re-screens among younger African-American women and those of higher income and education. Not using self-reports to base clinic decisions may still be prudent among those with less education.
Geometric integration in Born-Oppenheimer molecular dynamics.
Odell, Anders; Delin, Anna; Johansson, Börje; Cawkwell, Marc J; Niklasson, Anders M N
2011-12-14
Geometric integration schemes for extended Lagrangian self-consistent Born-Oppenheimer molecular dynamics, including a weak dissipation to remove numerical noise, are developed and analyzed. The extended Lagrangian framework enables the geometric integration of both the nuclear and electronic degrees of freedom. This provides highly efficient simulations that are stable and energy conserving even under incomplete and approximate self-consistent field (SCF) convergence. We investigate three different geometric integration schemes: (1) regular time reversible Verlet, (2) second order optimal symplectic, and (3) third order optimal symplectic. We look at energy conservation, accuracy, and stability as a function of dissipation, integration time step, and SCF convergence. We find that the inclusion of dissipation in the symplectic integration methods gives an efficient damping of numerical noise or perturbations that otherwise may accumulate from finite arithmetics in a perfect reversible dynamics. © 2011 American Institute of Physics
First-principles studies of electronic, transport and bulk properties of pyrite FeS2
NASA Astrophysics Data System (ADS)
Banjara, Dipendra; Mbolle, Augustine; Malozovsky, Yuriy; Franklin, Lashounda; Bagayoko, Diola
We present results of ab-initio, self-consistent density functional theory (DFT) calculations of electronic, transport, and bulk properties of pyrite FeS2. We employed a local density approximation (LDA) potential and the linear combination of atomic orbitals (LCAO) formalism, following the Bagayoko, Zhao and Williams (BZW) method, as enhanced by Ekuma and Franklin (BZW-EF). The BZW-EF method requires successive, self consistent calculations with increasing basis sets to reach the ground state of the system under study. We report the band structure, the band gap, total and partial densities of states, effective masses, and the bulk modulus. Work funded in part by the US Department of Energy (DOE), National Nuclear Security Administration (NNSA) (Award No.DE-NA0002630), the National Science Foundation (NSF) (Award No, 1503226), LaSPACE, and LONI-SUBR.
Vidal, Julien; Trani, Fabio; Bruneval, Fabien; Marques, Miguel A L; Botti, Silvana
2010-04-02
We use hybrid functionals and restricted self-consistent GW, state-of-the-art theoretical approaches for quasiparticle band structures, to study the electronic states of delafossite Cu(Al,In)O2, the first p-type and bipolar transparent conductive oxides. We show that a self-consistent GW approximation gives remarkably wider band gaps than all the other approaches used so far. Accounting for polaronic effects in the GW scheme we recover a very nice agreement with experiments. Furthermore, the modifications with respect to the Kohn-Sham bands are strongly k dependent, which makes questionable the common practice of using a scissor operator. Finally, our results support the view that the low energy structures found in optical experiments, and initially attributed to an indirect transition, are due to intrinsic defects in the samples.
Self-consistent Hartree-Fock RPA calculations in 208Pb
NASA Astrophysics Data System (ADS)
Taqi, Ali H.; Ali, Mohammed S.
2018-01-01
The nuclear structure of 208Pb is studied in the framework of the self-consistent random phase approximation (SCRPA). The Hartree-Fock mean field and single particle states are used to implement a completely SCRPA with Skyrme-type interactions. The Hamiltonian is diagonalised within a model space using five Skyrme parameter sets, namely LNS, SkI3, SkO, SkP and SLy4. In view of the huge number of the existing Skyrme-force parameterizations, the question remains which of them provide the best description of data. The approach attempts to accurately describe the structure of the spherical even-even nucleus 208Pb. To illustrate our approach, we compared the binding energy, charge density distribution, excitation energy levels scheme with the available experimental data. Moreover, we calculated isoscalar and isovector monopole, dipole, and quadrupole transition densities and strength functions.
Deutsch, Madeline B.; Peitzmeier, Sarah M.; White Hughto, Jaclyn M.; Cavanaugh, Timothy P.; Pardee, Dana J.; McLean, Sarah A.; Panther, Lori A.; Gelman, Marcy; Mimiaga, Matthew J.; Potter, Jennifer E.
2018-01-01
Background High-risk human papillomavirus (hrHPV) causes virtually all cervical cancers. Trans masculine (TM) people (those assigned female at birth who identify with a gender other than female) have low uptake of conventional cervical cancer screening. Self-collected hrHPV DNA testing has high levels of acceptability among cisgender (non-transgender) females and may support increased cervical cancer screening uptake in TM individuals. Objective To assess the test performance and acceptability of self-collected vaginal specimens in comparison to provider-collected cervical swabs for hrHPV DNA detection in TM individuals ages 21–64 years. Methods Between March 2015-September 2016, 150 TM participants with a cervix (mean age = 27.5 years; SD = 5.7) completed a one-time study visit comprised of a self-report survey, self-collected vaginal HPV DNA swab, clinician-administered cervical HPV swab, and brief interview on acceptability of clinical procedures. Participants were randomized to complete either self- or provider-collection first to minimize ordering effects. Self- and provider-collected samples were tested for 13 hrHPV DNA types using a DNA Hybridization Assay. The primary outcome variable was the concordance (kappa statistic) and performance (sensitivity, specificity) of self-collected vaginal HPV DNA specimens versus provider-collected cervical HPV swabs as the gold standard. Results Of the 131 participants completing both the self- and provider-collected HPV tests, 21 cases of hrHPV were detected by the provider cervical swab (gold standard; 16.0% hrHPV prevalence); 15 of these cases were accurately detected by the self-collected vaginal swab (71.4% concordance) (Kappa = 0.75, 95% Confidence Interval [CI]: 0.59, 0.92; p<0.001). Compared to the provider-collected cervical hrHPV DNA sample (gold standard), the self-collected vaginal hrHPV DNA test demonstrated a sensitivity of 71.4% (95% CI: 0.52, 0.91; p = 0.0495) and specificity of 98.2% (95% CI: 0.96, 1.00; p<0.0001). Over 90% of participants endorsed a preference for the self-collected vaginal swab over provider-collected cervical swab. Conclusion Self-collected vaginal swabs are highly acceptable to TM as a means to test for hrHPV DNA. Test performance of this self-collection method for hrHPV detection in TM is consistent with previous studies in cisgender females. Self-collected vaginal swab testing for hrHPV DNA represents a reasonable and patient-centered strategy for primary cervical cancer screening in TM patients unwilling to undergo provider collection of specimens via speculum exam. PMID:29538411
NASA Astrophysics Data System (ADS)
White, R. D.; Cocks, D.; Boyle, G.; Casey, M.; Garland, N.; Konovalov, D.; Philippa, B.; Stokes, P.; de Urquijo, J.; González-Magaña, O.; McEachran, R. P.; Buckman, S. J.; Brunger, M. J.; Garcia, G.; Dujko, S.; Petrovic, Z. Lj
2018-05-01
Accurate modelling of electron transport in plasmas, plasma-liquid and plasma-tissue interactions requires (i) the existence of accurate and complete sets of cross-sections, and (ii) an accurate treatment of electron transport in these gaseous and soft-condensed phases. In this study we present progress towards the provision of self-consistent electron-biomolecule cross-section sets representative of tissue, including water and THF, by comparison of calculated transport coefficients with those measured using a pulsed-Townsend swarm experiment. Water–argon mixtures are used to assess the self-consistency of the electron-water vapour cross-section set proposed in de Urquijo et al (2014 J. Chem. Phys. 141 014308). Modelling of electron transport in liquids and soft-condensed matter is considered through appropriate generalisations of Boltzmann’s equation to account for spatial-temporal correlations and screening of the electron potential. The ab initio formalism is applied to electron transport in atomic liquids and compared with available experimental swarm data for these noble liquids. Issues on the applicability of the ab initio formalism for krypton are discussed and addressed through consideration of the background energy of the electron in liquid krypton. The presence of self-trapping (into bubble/cluster states/solvation) in some liquids requires a reformulation of the governing Boltzmann equation to account for the combined localised–delocalised nature of the resulting electron transport. A generalised Boltzmann equation is presented which is highlighted to produce dispersive transport observed in some liquid systems.
Evaluation of a simple model of ethanol drinking to intoxication in C57BL/6J mice.
Rhodes, Justin S; Best, Karyn; Belknap, John K; Finn, Deborah A; Crabbe, John C
2005-01-31
Because of intrinsic differences between humans and mice, no single mouse model can represent all features of a complex human trait such as alcoholism. It is therefore necessary to develop partial models. One important feature is drinking to the point where blood ethanol concentration (BEC) reaches levels that have measurable affects on physiology and/or behavior (>1.0 mg ethanol/ml blood). Most models currently in use examine relative oral self-administration from a bottle containing alcohol versus one containing water (two-bottle preference drinking), or oral operant self-administration. In these procedures, it is not clear when or if the animals drink to pharmacologically significant levels because the drinking is episodic and often occurs over a 24-h period. The aim of this study was to identify the optimal parameters and evaluate the reliability of a very simple procedure, taking advantage of a mouse genotype (C57BL/6J) that is known to drink large quantities of ethanol. We exchanged for the water bottle a solution containing ethanol in tap water for a limited period, early in the dark cycle, in the home cage. Mice regularly drank sufficient ethanol to achieve BEC>1.0 mg ethanol/ml blood. The concentration of ethanol offered (10%, 20% or 30%) did not affect consumption in g ethanol/kg body weight. The highest average BEC ( approximately 1.6 mg/ml) occurred when the water-to-ethanol switch occurred 3 h into the dark cycle, and when the ethanol was offered for 4 rather than 2 h. Ethanol consumption was consistent within individual mice, and reliably predicted BEC after the period of ethanol access. C57BL/6J mice from three sources provided equivalent data, while DBA/2J mice drank much less than C57BL/6J in this test. We discuss advantages of the model for high-throughput screening assays where the goal is to find other genotypes of mice that drink excessively, or to screen drugs for their efficacy in blocking excessive drinking.
NASA Astrophysics Data System (ADS)
Chang, Vivide Tuan-Chyan; Merisier, Delson; Yu, Bing; Walmer, David K.; Ramanujam, Nirmala
2011-03-01
A significant challenge in detecting cervical pre-cancer in low-resource settings is the lack of effective screening facilities and trained personnel to detect the disease before it is advanced. Light based technologies, particularly quantitative optical spectroscopy, have the potential to provide an effective, low cost, and portable solution for cervical pre-cancer screening in these communities. We have developed and characterized a portable USB-powered optical spectroscopic system to quantify total hemoglobin content, hemoglobin saturation, and reduced scattering coefficient of cervical tissue in vivo. The system consists of a high-power LED as light source, a bifurcated fiber optic assembly, and two USB spectrometers for sample and calibration spectra acquisitions. The system was subsequently tested in Leogane, Haiti, where diffuse reflectance spectra from 33 colposcopically normal sites in 21 patients were acquired. Two different calibration methods, i.e., a post-study diffuse reflectance standard measurement and a real time self-calibration channel were studied. Our results suggest that a self-calibration channel enabled more accurate extraction of scattering contrast through simultaneous real-time correction of intensity drifts in the system. A self-calibration system also minimizes operator bias and required training. Hence, future contact spectroscopy or imaging systems should incorporate a selfcalibration channel to reliably extract scattering contrast.
NASA Astrophysics Data System (ADS)
Klimenko, M. V.; Klimenko, V. V.; Bryukhanov, V. V.
Inclusion in the Global Self-consistent Model of the Thermosphere Ionosphere and Protonosphere GSM TIP developed in WD IZMIRAN of the new block of the electric field calculation allows to carry out the investigation of the equatorial ionosphere In this block the decision of the three-dimensional equation of the full current density conservation in the ionosphere of the Earth is realized by adduction it to the two-dimensional by integration on thickness of the current conductive layer along geomagnetic field lines which are expected equipotential In the given work are presented the calculation results on the basis of the model GSM TIP in which the composition and the temperature of neutral atmosphere computed on the basis of model MSIS The calculations were carried out for the quiet equinox conditions in the minimum of the solar activity The magnetosphere convection field calculated in the model by two ways paid in models - by setting of the field aligned currents of the first zone or potential difference across the polar caps Herewith in the first variant of calculations the currents of the first zone were selected so as got the potential difference through the polar caps was approximately such as assigned in the second variant There are considered two events - an absence of the screening by Alfven layer electric field that is to say the absence of the field aligned currents of the second zone and presence of such screening under given field aligned currents of the second zone All calculations were carried out with taking into account of
Minami, Ryunosuke; Sato, Chiaki; Yamahama, Yumi; Kubo, Hideo; Hariyama, Takahiko; Kimura, Ken-Ichi
2016-12-01
The "moth-eye" structure, which is observed on the surface of corneal lens in several insects, supports anti-reflective and self-cleaning functions due to nanoscale protrusions known as corneal nipples. Although the morphology and function of the "moth-eye" structure, are relatively well studied, the mechanism of protrusion formation from cell-secreted substances is unknown. In Drosophila melanogaster, a compound eye consists of approximately 800 facets, the surface of which is formed by the corneal lens with nanoscale protrusions. In the present study, we sought to identify genes involved in "moth-eye" structure, formation in order to elucidate the developmental mechanism of the protrusions in Drosophila. We re-examined the aberrant patterns in classical glossy-eye mutants by scanning electron microscope and classified the aberrant patterns into groups. Next, we screened genes encoding putative structural cuticular proteins and genes involved in cuticular formation using eye specific RNAi silencing methods combined with the Gal4/UAS expression system. We identified 12 of 100 candidate genes, such as cuticular proteins family genes (Cuticular protein 23B and Cuticular protein 49Ah), cuticle secretion-related genes (Syntaxin 1A and Sec61 ββ subunit), ecdysone signaling and biosynthesis-related genes (Ecdysone receptor, Blimp-1, and shroud), and genes involved in cell polarity/cell architecture (Actin 5C, shotgun, armadillo, discs large1, and coracle). Although some of the genes we identified may affect corneal protrusion formation indirectly through general patterning defects in eye formation, these initial findings have encouraged us to more systematically explore the precise mechanisms underlying the formation of nanoscale protrusions in Drosophila.
Psychosocial impact of visual impairment and coping strategies in female ex-Service personnel.
Stevelink, Sharon A M; Fear, N T
2016-04-01
To examine how vision loss affects the psychosocial well-being of female ex-Service personnel and how they cope with their visual impairment. A cross-sectional study was conducted consisting of two study phases. During phase 1, a questionnaire was undertaken via the telephone with nine female ex-Service personnel (all under 55 years of age) using clinical screening measures to identify the probable presence of the following mental health disorders: depression (Patient Health Questionnaire-9), anxiety (Generalised Anxiety Disorder Assessment), post-traumatic stress disorder (PTSD, PTSD Checklist-Civilian) and alcohol misuse (Alcohol Use Disorders Identification Test). In phase 2, eight of the participants were interviewed face to face regarding the impact being visually impaired had had on their daily lives. Approximately 1 in 10 women screened positive for probable depression, probable PTSD or alcohol misuse; 1 in 5 fulfilled the criteria for probable anxiety disorder. Participants struggled to adjust to the loss of vision and its impact on their lives. They reported low self-esteem, feeling down and social withdrawal. As time went by, the women were able to apply various coping strategies such as having a positive attitude, relearning skills and integrating low vision aids in their daily routine. However, some coping strategies, such as alcohol misuse and lack of help-seeking when needed, hindered participants' success in adjusting to their visual impairment. Sustaining a visual impairment negatively affects psychosocial well-being in female ex-Service personnel. Over time, participants learnt to cope with the challenges and limitations associated with being visually impaired. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Perceptions of Self-Testing for Chlamydia: Understanding and Predicting Self-Test Use.
Powell, Rachael; Pattison, Helen M; Marriott, John F
2016-05-10
Self-testing technology allows people to test themselves for chlamydia without professional support. This may result in reassurance and wider access to chlamydia testing, but anxiety could occur on receipt of positive results. This study aimed to identify factors important in understanding self-testing for chlamydia outside formal screening contexts, to explore the potential impacts of self-testing on individuals, and to identify theoretical constructs to form a Framework for future research and intervention development. Eighteen university students participated in semi-structured interviews; eleven had self-tested for chlamydia. Data were analysed thematically usingaFrameworkapproach. Perceivedbenefitsofself-testingincludeditsbeingconvenient, anonymousandnotrequiringphysicalexamination. Therewasconcernabouttestaccuracyandsome participants lacked confidence in using vulvo-vaginal swabs. While some participants expressed concern about the absence of professional support, all said they would seek help on receiving a positive result. Factors identified in Protection Motivation Theory and the Theory of Planned Behaviour, such as response efficacy and self-efficacy, were found to be highly salient to participants in thinking about self-testing. These exploratory findings suggest that self-testing independentlyofformalhealthcaresystemsmaynomorenegativelyimpactpeoplethanbeingtested by health care professionals. Participants' perceptions about self-testing behaviour were consistent with psychological theories. Findings suggest that interventions which increase confidence in using self-tests and that provide reassurance of test accuracy may increase self-test intentions.
NASA Astrophysics Data System (ADS)
Aizawa, Hirohito; Kuroki, Kazuhiko
2018-03-01
We present a first-principles band calculation for the quasi-one-dimensional (Q1D) organic superconductor (TMTSF) 2ClO4 . An effective tight-binding model with the TMTSF molecule to be regarded as the site is derived from a calculation based on maximally localized Wannier orbitals. We apply a two-particle self-consistent (TPSC) analysis by using a four-site Hubbard model, which is composed of the tight-binding model and an onsite (intramolecular) repulsive interaction, which serves as a variable parameter. We assume that the pairing mechanism is mediated by the spin fluctuation, and the sign of the superconducting gap changes between the inner and outer Fermi surfaces, which correspond to a d -wave gap function in a simplified Q1D model. With the parameters we adopt, the critical temperature for superconductivity estimated by the TPSC approach is approximately 1 K, which is consistent with experiment.
Baracco, G J; Eisert, S; Saavedra, S; Hirsch, P; Marin, M; Ortega-Sanchez, I R
2015-10-01
Exposure to patients with varicella or herpes zoster causes considerable disruption to a health care facility's operations and has a significant health and economic impact. However, practices related to screening for immunity and immunization of health care personnel (HCP) for varicella vary widely. A decision tree model was built to evaluate the cost-effectiveness of 8 different strategies of screening and vaccinating HCP for varicella. The outcomes are presented as probability of acquiring varicella, economic impact of varicella per employee per year, and cost to prevent additional cases of varicella. Monte Carlo simulations and 1-way sensitivity analyses were performed to address the uncertainties inherent to the model. Alternative epidemiologic and technologic scenarios were also analyzed. Performing a clinical screening followed by serologic testing of HCP with negative history diminished the cost impact of varicella by >99% compared with not having a program. Vaccinating HCP with negative screen cost approximately $50,000 per case of varicella prevented at the current level of U.S. population immunity, but was projected to be cost-saving at 92% or lower immunity prevalence. Improving vaccine acceptance rates and using highly sensitive assays also optimize cost-effectiveness. Strategies relying on screening and vaccinating HCP for varicella on employment were shown to be cost-effective for health care facilities and are consistent with current national guidelines for varicella prevention. Published by Elsevier Inc.
Arrossi, Silvina; Paolino, Melisa; Thouyaret, Laura; Laudi, Rosa; Campanera, Alicia
2017-02-13
Self-collection has been proposed as a strategy to increase cervical screening coverage among hard-to-reach women. However, evaluations of the implementation of this strategy on a large scale are scarce. This paper describes the process and measurement of the scaling-up of self-collection offered by community health workers during home visits as a strategy to reach under-screened women aged 30+ with public health coverage, defined as the target women. We used an adaptation of the Health System Framework to analyze key drivers of scaling-up. A content analysis approach was used to collect and analyze information from different sources. The RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) model was used to evaluate the impact of the strategy. HPV self-collection was scaled-up in the province of Jujuy in 2014 after a RCT (Self-collection Modality Trial, initials EMA in Spanish) was carried out locally in 2012 and demonstrated effectiveness of the strategy to increase screening uptake. Facilitators of scaling-up were the organizational capacity of the provincial health system, sustainable funding for HPV testing, and local consensus about the value of the technology. Reach: In 2014, 9% (2983/33,245) of target women were screened through self-collection in the Jujuy public health sector. Effectiveness: In 2014, 17% (n = 5657/33,245) of target women were screened with any HPV test (self-collected and clinician-collected tests) vs. 11.7% (4579/38,981) in 2013, the pre-scaling-up period (p < 0.0001). Training about the strategy was provided to 84.2% (n = 609/723) of total community health workers (CHWs). Of 414 HPV+ women, 77.5% (n = 320) had follow-up procedures. Of 113 women with positive triage, 66.4% (n = 75) had colposcopic diagnosis. Treatment was provided to 80.7% of CIN2+ women (n = 21/26). Adoption: Of trained CHWs, 69.3% (n = 422/609) had at least one woman with self-collection; 85.2% (n = 315/368) of CHWs who responded to an evaluation survey were satisfied with self-collection strategy. Maintenance: During 2015, 100.0% (723/723) CHWs were operational and 63.8% (461/723) had at least one woman with self-collection. The strategy was successfully scaled-up, with a high level of adoption among CHWs, which resulted in increased screening among socially vulnerable under-screened women.
Buchberg, Meredith; Schover, Leslie; Basen-Engquist, Karen; Kempf, Mirjam-Colette; Arduino, Roberto C.; Vidrine, Damon J.
2014-01-01
Significantly elevated rates of cervical cancer and low rates of Papanicolaou (Pap) smear screening have been documented among HIV-infected women. However, little is known about women’s perceptions of cervical cancer screening utilization. Hence, this study describes barriers and facilitators related to cervical cancer screening in a sample of HIV-infected women seeking care at an integrated HIV clinic in Houston, Texas. Using an inductive qualitative methodological approach, data were obtained from five focus group discussions with a total of 33, HIV-infected women. The majority of the study sample consisted of women who self-identified as Black (69.7%), and reported heterosexual contact as the mode of HIV acquisition (75.8%). Barriers to cervical cancer screening were described as pain and discomfort associated with receiving Pap smears and subsequent procedures; lack of awareness of cervical cancer as a preventable disease; limited transportation access; and systemic issues as it relates to scheduling gynecological appointments. Facilitators were described as awareness of HIV-infected women’s increased risk of cervical cancer and strong provider-patient relationships. To address disparities in cervical cancer screening among low-income HIV-infected women, programs should capitalize on the identified facilitators and alleviate modifiable barriers using multi-level strategies. PMID:24635664
Lange, S; Quere, M; Shield, K; Rehm, J; Popova, S
2016-05-01
To estimate the prevalence of alcohol consumption during pregnancy and while breastfeeding in Canada from 2003 to 2010, and to test the relation between self-perceived mental health status and alcohol consumption during pregnancy and while breastfeeding. Secondary analysis of four cycles of the Canadian Community Health Survey, a population-based cross-sectional survey. Canada. A total of 18 612 pregnant and 15 836 breastfeeding women. The prevalence of alcohol consumption during pregnancy and while breastfeeding and 95% confidence intervals (CI) were calculated by province and territory, and cycle. The relation between self-perceived mental health status and alcohol consumption during pregnancy and while breastfeeding was explored using quasi-Poisson regression models. Alcohol consumption during pregnancy and while breastfeeding, and self-perceived mental health status. In Canada, between 2003 and 2010, approximately one in every ten pregnant women (9.9%; 95%CI 9.2-10.5%) and two in every ten breastfeeding women (20.3%; 95%CI 19.4-21.2%) women consumed alcohol. Women with a lower self-perceived mental health status (i.e. 'good') were 1.40 (95%CI 1.18-1.67, P < 0.001) times more likely to have consumed alcohol during pregnancy, compared with women with an 'excellent' self-perceived mental health. There were no notable differences between the categories of mental health status in regard to alcohol consumption while breastfeeding. Despite public health efforts in Canada, a significant proportion of pregnant and breastfeeding women consume alcohol. It is imperative that a standard screening protocol be initiated among pregnant and breastfeeding women, especially in high-risk populations (e.g. women utilising substance abuse treatment programs). In Canada in 2003-2010, approximately 10% of pregnant and 20% of breastfeeding women consumed alcohol. © 2015 Royal College of Obstetricians and Gynaecologists.
Jackman, Kate; Honig, Judy; Bockting, Walter
2016-12-01
To conduct an integrative review of nonsuicidal self-injury among lesbian, gay, bisexual and transgender populations to better understand the prevalence; to identify the lesbian, gay, bisexual and transgender subgroups at increased risk for nonsuicidal self-injury; and to examine the risk factors associated with nonsuicidal self-injury among lesbian, gay, bisexual and transgender populations. Nonsuicidal self-injury, defined as intentional injury to the body's surface without intent to die, is a significant mental health concern among adolescents and adults. Mental health disparities in lesbian, gay, bisexual and transgender populations, including anxiety, depression and suicidality, have been documented in the scientific literature with little focus on findings about nonsuicidal self-injury. Integrative literature review of published quantitative and qualitative empirical research. A literature search of 11 on-line databases was conducted of articles published through April 2015. Keywords were used to identify articles about lesbian, gay, bisexual and transgender populations and nonsuicidal self-injury. After screening by title, abstract and full text, 26 articles were included in this review. The literature synthesised demonstrates a consistent pattern of increased prevalence of nonsuicidal self-injury among sexual and gender minority populations compared with heterosexual peers. This body of literature indicates which subgroups of the lesbian, gay, bisexual and transgender populations appear to be at increased risk for nonsuicidal self-injury and which specific factors contributing to vulnerability to nonsuicidal self-injury among these populations. Lesbian, gay, bisexual and transgender populations are at higher risk for nonsuicidal self-injury compared with the general population. Lesbian, gay, bisexual and transgender-specific and general risk factors appear to contribute to this heightened vulnerability. Clinical nurses should screen for nonsuicidal self-injury and for sexual and gender minority identity in all of their patients. Comprehensive assessment of lesbian, gay, bisexual and transgender patients presenting with nonsuicidal self-injury may lead to identification of risk factors that can be addressed through nursing interventions. Nurse researchers and clinicians should take an active role in developing and implementing evidenced-based tailored interventions to reduce the higher vulnerability to nonsuicidal self-injury among lesbian, gay, bisexual and transgender populations. © 2016 John Wiley & Sons Ltd.
Vanoh, Divya; Shahar, Suzana; Rosdinom, Razali; Din, Normah Che; Yahya, Hanis Mastura; Omar, Azahadi
2016-01-01
Background and aim Focus on screening for cognitive impairment has to be given particular importance because of the rising older adult population. Thus, this study aimed to develop and assess a brief screening tool consisting of ten items that can be self-administered by community dwelling older adults (TUA-WELLNESS). Methodology A total of 1,993 noninstitutionalized respondents aged 60 years and above were selected for this study. The dependent variable was mild cognitive impairment (MCI) assessed using neuropsychological test batteries. The items for the screening tool comprised a wide range of factors that were chosen mainly from the analysis of ordinal logistic regression (OLR) and based on past literature. A suitable cut-off point was developed using receiver operating characteristic analysis. Results A total of ten items were included in the screening tool. From the ten items, eight were found to be significant by ordinal logistic regression and the remaining two items were part of the tool because they showed strong association with cognitive impairment in previous studies. The area under curve (AUC), sensitivity, and specificity for cut-off 11 were 0.84%, 83.3%, and 73.4%, respectively. Conclusion TUA-WELLNESS screening tool has been used to screen for major risk factors of MCI among Malaysian older adults. This tool is only suitable for basic MCI risk screening purpose and should not be used for diagnostic purpose. PMID:27274208
Screen time, weight status and the self-concept of physical attractiveness in adolescents.
Suchert, Vivien; Hanewinkel, Reiner; Isensee, Barbara
2016-04-01
Adolescents in modern societies spend about 3 h per day in front of small recreational screens. The present study aims at investigating the relationships between screen time and different indicators of overweight. In addition, associations with the self-concept of physical attractiveness and perceived weight status will be examined. In a total sample of 1228 students (47.5% girls) aged 12-17 years (M = 13.74, SD = 0.68) cross-sectional associations were determined by conducting multiple linear regression analyses. Screen time showed a significant positive dose-response relationship with body mass index percentile, waist circumference, body fat, waist-to-height-ratio, and a negative association with self-concept of physical attractiveness independent of age, gender and moderate to vigorous physical activity. Thus, screen time seems to be associated with adolescent overweight, abdominal obesity, and body dissatisfaction. Reducing adolescents' screen time could be a promising approach for primary prevention of obesity and for the promotion of a positive physical self-concept. Copyright © 2016 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.
Donlan, William; Lee, Junghee
2010-04-01
U.S. farmworkers include growing numbers of individuals from indigenous, pre-Columbian communities in southern Mexico with distinctive languages and cultures. Given the high stress these farmworkers experience in their challenging work environments, they are very susceptible to depression and other mental and emotional health disorders. The present study explores the Spanish version of the Patient Health Questionnaire-9 (PHQ-9) as a screen for the presence and severity of depression among 123 indigenous Mexican-origin, migrant farmworkers in Oregon. Factor structure and inter-item correlations of the PHQ-9 are examined, along with associations between depression and culture-bound syndromes, self-esteem, self-efficacy, acculturation stress, and other sample psychosocial characteristics. The PHQ-9 exhibited strong factor loadings and internal consistency, and its severity score significantly correlated with other indicators of health status that were observed in previous studies to be significantly associated with depression. The PHQ-9 appears to be culturally relevant for use with Mexicans coming from a variety of indigenous cultures and having very low education and literacy.
Early-onset restrictive eating disturbances in primary school boys and girls.
Kurz, Susanne; van Dyck, Zoé; Dremmel, Daniela; Munsch, Simone; Hilbert, Anja
2015-07-01
This study sought to determine the distribution of early-onset restrictive eating disturbances characteristic of the new DSM-5 diagnosis, avoidant/restrictive food intake disorder (ARFID) in middle childhood, as well as to evaluate the screening instrument, Eating Disturbances in Youth-Questionnaire (EDY-Q). A total of 1,444 8- to 13-year-old children were screened in regular schools (3rd to 6th grade) in Switzerland using the self-report measure EDY-Q, consisting of 12 items based on the DSM-5 criteria for ARFID. 46 children (3.2%) reported features of ARFID in the self-rating. Group differences were found for body mass index, with underweight children reporting features of ARFID more often than normal and overweight children. The EDY-Q revealed good psychometric properties, including adequate discriminant and convergent validity. Early-onset restrictive eating disturbances are commonly reported in middle childhood. Because of possible negative short- and long-term impact, early detection is essential. Further studies with structured interviews and parent reports are needed to confirm this study's findings.
Fractal structure of the interplanetary magnetic field
NASA Technical Reports Server (NTRS)
Burlaga, L. F.; Klein, L. W.
1985-01-01
Under some conditions, time series of the interplanetary magnetic field strength and components have the properties of fractal curves. Magnetic field measurements made near 8.5 AU by Voyager 2 from June 5 to August 24, 1981 were self-similar over time scales from approximately 20 sec to approximately 3 x 100,000 sec, and the fractal dimension of the time series of the strength and components of the magnetic field was D = 5/3, corresponding to a power spectrum P(f) approximately f sup -5/3. Since the Kolmogorov spectrum for homogeneous, isotropic, stationary turbulence is also f sup -5/3, the Voyager 2 measurements are consistent with the observation of an inertial range of turbulence extending over approximately four decades in frequency. Interaction regions probably contributed most of the power in this interval. As an example, one interaction region is discussed in which the magnetic field had a fractal dimension D = 5/3.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Franović, Igor, E-mail: franovic@ipb.ac.rs; Todorović, Kristina; Burić, Nikola
We use the mean-field approach to analyze the collective dynamics in macroscopic networks of stochastic Fitzhugh-Nagumo units with delayed couplings. The conditions for validity of the two main approximations behind the model, called the Gaussian approximation and the Quasi-independence approximation, are examined. It is shown that the dynamics of the mean-field model may indicate in a self-consistent fashion the parameter domains where the Quasi-independence approximation fails. Apart from a network of globally coupled units, we also consider the paradigmatic setup of two interacting assemblies to demonstrate how our framework may be extended to hierarchical and modular networks. In both cases,more » the mean-field model can be used to qualitatively analyze the stability of the system, as well as the scenarios for the onset and the suppression of the collective mode. In quantitative terms, the mean-field model is capable of predicting the average oscillation frequency corresponding to the global variables of the exact system.« less
Reuland, Daniel S; Ko, Linda K; Fernandez, Alicia; Braswell, Laura C; Pignone, Michael
2012-06-12
Compared with non-Latinos, Latinos in the US have low rates of colorectal cancer (CRC) screening and low rates of knowledge regarding CRC screening tests and guidelines. Spanish speaking Latinos have particularly low CRC screening rates and screening knowledge. Our purpose was twofold: (1) to evaluate the effect of a computer-based, Spanish-language CRC screening decision aid on screening knowledge, intent to obtain screening, and screening self-efficacy in a community sample of Latinos with limited English proficiency (LEP); and (2) to survey these decision aid viewers at four months to determine their rates of CRC discussions with a health care provider as well as their rates of screening test completion. We recruited 50-75 year old Latinos with LEP who were not current with CRC. Participants screening viewed a 14 minute multimedia decision aid that addresses CRC screening rationale, recommendations, and options. We conducted an uncontrolled (pre-post) study in which we assessed screening knowledge, self-efficacy, and intent at baseline and immediately after decision aid viewing. We also conducted a follow-up telephone survey of participants at four months to examine rates of patient-provider screening discussions and test completion. Among n = 80 participants, knowledge scores increased from 20% (before) to 72% (after) decision aid viewing (absolute difference [95%CI]: 52% [46, 59]). The proportion with high screening self-efficacy increased from 67% to 92% (25% [13, 37]); the proportion with high screening intent increased from 63% to 95% (32% [21, 44]). We reached 68 (85%) of 80 participants eligible for the follow-up survey. Of these 36 (53%) reported discussing screening with a provider and 13 (19%) completed a test. Viewing a Spanish-language decision aid increased CRC screening knowledge, self-efficacy, and intent among Latinos with LEP. Decision aid viewing appeared to promote both CRC screening discussions with health care providers and test completion. The decision aid may be an effective tool for promoting CRC screening and reducing screening disparities in this population.
Epidemiology and costs of cervical cancer screening and cervical dysplasia in Italy
Rossi, Paolo Giorgi; Ricciardi, Alessandro; Cohet, Catherine; Palazzo, Fabio; Furnari, Giacomo; Valle, Sabrina; Largeron, Nathalie; Federici, Antonio
2009-01-01
Background We estimated the number of women undergoing cervical cancer screening annually in Italy, the rates of cervical abnormalities detected, and the costs of screening and management of abnormalities. Methods The annual number of screened women was estimated from National Health Interview data. Data from the Italian Group for Cervical Cancer Screening were used to estimate the number of positive, negative and unsatisfactory Pap smears. The incidence of CIN (cervical intra-epithelial neoplasia) was estimated from the Emilia Romagna Cancer Registry. Patterns of follow-up and treatment costs were estimated using a typical disease management approach based on national guidelines and data from the Italian Group for Cervical Cancer Screening. Treatment unit costs were obtained from Italian National Health Service and Hospital Information System of the Lazio Region. Results An estimated 6.4 million women aged 25–69 years undergo screening annually in Italy (1.2 million and 5.2 million through organized and opportunistic screening programs, respectively). Approximately 2.4% of tests have positive findings. There are approximately 21,000 cases of CIN1 and 7,000–17,000 cases of CIN2/3. Estimated costs to the healthcare service amount to €158.5 million for screening and €22.9 million for the management of cervical abnormalities. Conclusion Although some cervical abnormalities might have been underestimated, the total annual cost of cervical cancer prevention in Italy is approximately €181.5 million, of which 87% is attributable to screening. PMID:19243586
Mitchell, Sheona M; Pedersen, Heather N; Eng Stime, Evelyn; Sekikubo, Musa; Moses, Erin; Mwesigwa, David; Biryabarema, Christine; Christilaw, Jan; Byamugisha, Josaphat K; Money, Deborah M; Ogilvie, Gina S
2017-01-13
Women living with HIV (WHIV) are disproportionately impacted by cervical dysplasia and cancer. The burden is greatest in low-income countries where limited or no access to screening exists. The goal of this study was to describe knowledge and intentions of WHIV towards HPV self-collection for cervical cancer screening, and to report on factors related to HPV positivity among women who participated in testing. A validated survey was administered to 87 HIV positive women attending the Kisenyi Health Unit aged 30-69 years old, and data was abstracted from chart review. At a later date, self-collection based HPV testing was offered to all women. Specimens were tested for high risk HPV genotypes, and women were contacted with results and referred for care. Descriptive statistics, Chi Square and Fischer-exact statistical tests were performed. The vast majority of WHIV (98.9%) women did not think it necessary to be screened for cervical cancer and the majority of women had never heard of HPV (96.4%). However, almost all WHIV found self-collection for cervical cancer screening to be acceptable. Of the 87 WHIV offered self-collection, 40 women agreed to provide a sample at the HIV clinic. Among women tested, 45% were oncogenic HPV positive, where HPV 16 or 18 positivity was 15% overall. In this group of WHIV engaged in HIV care, there was a high prevalence of oncogenic HPV, a large proportion of which were HPV genotypes 16 or 18, in addition to low knowledge of HPV and cervical cancer screening. Improved education and cervical cancer screening for WHIV are sorely needed; self-collection based screening has the potential to be integrated with routine HIV care in this setting.
Kenney, Erica L; Gortmaker, Steven L
2017-03-01
To quantify the relationships between youth use of television (TV) and other screen devices, including smartphones and tablets, and obesity risk factors. TV and other screen device use, including smartphones, tablets, computers, and/or videogames, was self-reported by a nationally representative, cross-sectional sample of 24 800 US high school students (2013-2015 Youth Risk Behavior Surveys). Students also reported on health behaviors including sugar-sweetened beverage (SSB) intake, physical activity, sleep, and weight and height. Sex-stratified logistic regression models, adjusting for the sampling design, estimated associations between TV and other screen device use and SSB intake, physical activity, sleep, and obesity. Approximately 20% of participants used other screen devices for ≥5 hours daily. Watching TV ≥5 hours daily was associated with daily SSB consumption (aOR = 2.72, 95% CI: 2.23, 3.32) and obesity (aOR = 1.78, 95% CI: 1.40, 2.27). Using other screen devices ≥5 hours daily was associated with daily SSB consumption (aOR = 1.98, 95% CI: 1.69, 2.32), inadequate physical activity (aOR = 1.94, 95% CI: 1.69, 2.25), and inadequate sleep (aOR = 1.79, 95% CI: 1.54, 2.08). Using smartphones, tablets, computers, and videogames is associated with several obesity risk factors. Although further study is needed, families should be encouraged to limit both TV viewing and newer screen devices. Copyright © 2016 Elsevier Inc. All rights reserved.
Physical activity and sedentary behaviour in European children: the IDEFICS study.
Santaliestra-Pasías, Alba Ma; Mouratidou, Theodora; Verbestel, Vera; Bammann, Karin; Molnar, Dénes; Sieri, Sabina; Siani, Alfonso; Veidebaum, Toomas; Mårild, Staffan; Lissner, Lauren; Hadjigeorgiou, Charalambos; Reisch, Lucia; De Bourdeaudhuij, Ilse; Moreno, Luis A
2014-10-01
To estimate the prevalence of physical activity and sedentary behaviours in European children, and to evaluate the relationship between media availability in personal space and physical activity in relation to total screen time. Data from the baseline IDEFICS (Identification and prevention of dietary- and lifestyle-induced health effects in children and infants) cross-sectional survey. Information on hours of television/digital video disk/video viewing and computer/games-console use (weekday and weekend days), media device availability in personal space, sports club membership, hours of active organized play and commuting (to and from school) were assessed via a self-reported parental questionnaire. Total screen time was defined as the sum of daily media use and subsequently dichotomized into meeting or not meeting the guidelines of the American Academy of Pediatrics. Eight survey centres (Italy, Estonia, Cyprus, Belgium, Sweden, Germany, Hungary and Spain). Children (n 15 330; 51% males) aged 2-10 years. Percentage of children engaged in total screen time for >2 h/d was higher on weekend days (52% v. 20% on weekdays) and in the older group (71% in males; 57% in females), varying by country. Children with a television set in their bedroom were more likely not to meet the screen time recommendations (OR = 1·54; 95% CI 1·60, 1·74). Approximately a third of the children failed to meet current screen time recommendations. Availability of a television set in personal space increased the risk of excess total screen time. This information could be used to identify potential targets for public health promotion actions of young population groups.
The role of acculturation and collectivism in cancer screening for Vietnamese American women.
Nguyen, Anh B; Clark, Trenette T
2014-01-01
The aim of this study was to examine the influence of demographic variables and the interplay between collectivism and acculturation on breast and cervical cancer screening outcomes among Vietnamese American women. Convenience sampling was used to recruit 111 Vietnamese women from the Richmond, VA, metropolitan area, who participated in a larger cancer screening intervention. All participants completed measures on demographic variables, collectivism, acculturation, and cancer-screening-related variables (i.e., attitudes, self-efficacy, and screening behavior). Findings indicated that collectivism predicted both positive attitudes and higher levels of self-efficacy with regard to breast and cervical cancer screening. Collectivism also moderated the relationship between acculturation and attitudes toward breast cancer screening such that for women with low levels of collectivistic orientation, increasing acculturation predicted less positive attitudes towards breast cancer screening. This relationship was not found for women with high levels of collectivistic orientation. The current findings highlight the important roles that sociodemographic and cultural variables play in affecting health attitudes, self-efficacy, and behavior among Vietnamese women. The findings potentially inform screening programs that rely on culturally relevant values in helping increase Vietnamese women's motivation to screen.
The Role of Acculturation and Collectivism in Cancer Screening for Vietnamese American Women
NGUYEN, ANH B.; CLARK, TRENETTE T.
2017-01-01
The aim of this study was to examine the influence of demographic variables and the interplay between collectivism and acculturation on breast and cervical cancer screening outcomes among Vietnamese American women. Convenience sampling was used to recruit 111 Vietnamese women from the Richmond, VA, metropolitan area, who participated in a larger cancer screening intervention. All participants completed measures on demographic variables, collectivism, acculturation, and cancer-screening-related variables (i.e., attitudes, self-efficacy, and screening behavior). Findings indicated that collectivism predicted both positive attitudes and higher levels of self-efficacy with regard to breast and cervical cancer screening. Collectivism also moderated the relationship between acculturation and attitudes toward breast cancer screening such that for women with low levels of collectivistic orientation, increasing acculturation predicted less positive attitudes towards breast cancer screening. This relationship was not found for women with high levels of collectivistic orientation. The current findings highlight the important roles that sociodemographic and cultural variables play in affecting health attitudes, self-efficacy, and behavior among Vietnamese women. The findings potentially inform screening programs that rely on culturally relevant values in helping increase Vietnamese women’s motivation to screen. PMID:24313445
Ando, Tadashi; Chow, Edmond; Skolnick, Jeffrey
2013-01-01
Hydrodynamic interactions exert a critical effect on the dynamics of macromolecules. As the concentration of macromolecules increases, by analogy to the behavior of semidilute polymer solutions or the flow in porous media, one might expect hydrodynamic screening to occur. Hydrodynamic screening would have implications both for the understanding of macromolecular dynamics as well as practical implications for the simulation of concentrated macromolecular solutions, e.g., in cells. Stokesian dynamics (SD) is one of the most accurate methods for simulating the motions of N particles suspended in a viscous fluid at low Reynolds number, in that it considers both far-field and near-field hydrodynamic interactions. This algorithm traditionally involves an O(N3) operation to compute Brownian forces at each time step, although asymptotically faster but more complex SD methods are now available. Motivated by the idea of hydrodynamic screening, the far-field part of the hydrodynamic matrix in SD may be approximated by a diagonal matrix, which is equivalent to assuming that long range hydrodynamic interactions are completely screened. This approximation allows sparse matrix methods to be used, which can reduce the apparent computational scaling to O(N). Previously there were several simulation studies using this approximation for monodisperse suspensions. Here, we employ newly designed preconditioned iterative methods for both the computation of Brownian forces and the solution of linear systems, and consider the validity of this approximation in polydisperse suspensions. We evaluate the accuracy of the diagonal approximation method using an intracellular-like suspension. The diffusivities of particles obtained with this approximation are close to those with the original method. However, this approximation underestimates intermolecular correlated motions, which is a trade-off between accuracy and computing efficiency. The new method makes it possible to perform large-scale and long-time simulation with an approximate accounting of hydrodynamic interactions. PMID:24089734
De Lepeleere, Sara; De Bourdeaudhuij, Ilse; Cardon, Greet; Verloigne, Maïté
2015-09-07
To assess the association between specific parenting practices and related parental self-efficacy with children's physical activity (PA) and screen time. Parental body mass index (BMI), family socioeconomic status (SES), and child's age and gender were examined as possible influencing factors. Cross-sectional. January 2014, Flanders (Belgium). 207 parents (87.4% mothers) of children aged 6-12 years. Specific parenting practices, related parental self-efficacy, and children's PA and screen time. The majority of investigated parenting practices and related parental self-efficacy were not significantly associated with children's PA or screen time. However, children were more physically active if sports equipment was available at home (p<0.10) and if parents did not find it difficult to motivate their child to be physically active (p<0.05). Children had a lower screen time if parents limited their own gaming (p<0.01). The associations between parenting practices and related parental self-efficacy with children's PA or screen time were significant for parents with a normal BMI, for medium-high SES families and for parents of younger children. Furthermore, the association between the parenting relating factors and children's PA and screen time differed for boys and girls. In contrast to what we expected, the findings of the current study show that only a very few specific parenting practices and related parental self-efficacy were associated with children's PA and screen time. It was expected that parental self-efficacy would play a more important role. This can be due to the fact that parental self-efficacy was already high in this group of parents. Therefore, it is possible that parents do not realise how difficult it is to perform certain parenting practices until they are faced with it in an intervention. EC/2012/317. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.
Branes in Extended Spacetime: Brane Worldvolume Theory Based on Duality Symmetry.
Sakatani, Yuho; Uehara, Shozo
2016-11-04
We propose a novel approach to the brane worldvolume theory based on the geometry of extended field theories: double field theory and exceptional field theory. We demonstrate the effectiveness of this approach by showing that one can reproduce the conventional bosonic string and membrane actions, and the M5-brane action in the weak-field approximation. At a glance, the proposed 5-brane action without approximation looks different from the known M5-brane actions, but it is consistent with the known nonlinear self-duality relation, and it may provide a new formulation of a single M5-brane action. Actions for exotic branes are also discussed.
Constraint on the second functional derivative of the exchange-correlation energy
NASA Astrophysics Data System (ADS)
Joubert, D. P.
2012-09-01
Using the density functional adiabatic connection approach for an N-electron system it is shown that ? γ is the coupling constant that scales the electron-electron interaction strength. For the non-interacting Kohn-Sham Hamiltonian γ = 0 and for the fully interacting system γ = 1. ? is the Hartree plus exchange-correlation energy while f 0(r) and fγ(r) are the Fukui functions of the non-interacting and interacting systems, respectively. This identity can serve to test the internal self-consistency or quality of approximate functionals. The quality of some popular approximate exchange and correlation functionals are tested for a simple model system.
Bulk and surface electronic structures of MgO
NASA Astrophysics Data System (ADS)
Schönberger, U.; Aryasetiawan, F.
1995-09-01
The bulk electronic structure of MgO is calculated from first principles including correlation effects within the GW approximation. The band gap, the position of the 2s O band, and the valence band width are in good agreement with experiment. From the quasiparticle band structure, optical transitions corresponding to the main optical absorption peaks are identified. The energy-loss spectrum is also calculated and compared with experiment. The surface electronic structure of MgO(100) is calculated self-consistently within the local-density approximation. It is found that states observed in a recent photoemission experiment outside the bulk allowed states are close to surface states.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Buda, I. G.; Lane, C.; Barbiellini, B.
We discuss self-consistently obtained ground-state electronic properties of monolayers of graphene and a number of ’beyond graphene’ compounds, including films of transition-metal dichalcogenides (TMDs), using the recently proposed strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA) to the density functional theory. The SCAN meta-GGA results are compared with those based on the local density approximation (LDA) as well as the generalized gradient approximation (GGA). As expected, the GGA yields expanded lattices and softened bonds in relation to the LDA, but the SCAN meta-GGA systematically improves the agreement with experiment. Our study suggests the efficacy of the SCAN functionalmore » for accurate modeling of electronic structures of layered materials in high-throughput calculations more generally.« less
Buda, I. G.; Lane, C.; Barbiellini, B.; ...
2017-03-23
We discuss self-consistently obtained ground-state electronic properties of monolayers of graphene and a number of ’beyond graphene’ compounds, including films of transition-metal dichalcogenides (TMDs), using the recently proposed strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA) to the density functional theory. The SCAN meta-GGA results are compared with those based on the local density approximation (LDA) as well as the generalized gradient approximation (GGA). As expected, the GGA yields expanded lattices and softened bonds in relation to the LDA, but the SCAN meta-GGA systematically improves the agreement with experiment. Our study suggests the efficacy of the SCAN functionalmore » for accurate modeling of electronic structures of layered materials in high-throughput calculations more generally.« less
McDowell, Michal; Pardee, Dana J; Peitzmeier, Sarah; Reisner, Sari L; Agénor, Madina; Alizaga, Natalie; Bernstein, Ida; Potter, Jennifer
2017-08-01
Trans-masculine (TM, i.e., persons who have a masculine spectrum gender identity, but were assigned female sex at birth) individuals face disparities in cervical cancer screening rates compared to cisgender women. Some unique barriers to screening in this population are specific to Pap tests. Introduction of self-collected frontal (i.e., vaginal) swabs for human papillomavirus (HPV) testing as a screening strategy may obviate these barriers. This study elucidates cervical cancer screening preferences among TM individuals. TM individuals participated in in-depth interviews (n = 31) and online surveys (n = 32) to explore perceptions and experiences regarding cervical cancer screening, including the acceptability of self-collected frontal HPV swabs for cervical cancer screening compared to provider-administered Pap tests. Provider-collected frontal HPV swab acceptability was also explored. Most TM individuals (94% in-person and 91% online participants) preferred either the self- or provider-collected frontal HPV swab to the Pap test. Participants perceived self- and provider-collected frontal HPV swabs to be less invasive, provoke less gender discordance, and promote a greater sense of agency compared to Pap tests. However, some participants expressed concern about HPV swab accuracy and, regarding the self-collected swab, discomfort about the need to engage with genitals they may not want to acknowledge. Individuals who reported positive provider relationships found Pap tests and provider-collected frontal swabs more acceptable than those who did not. Frontal HPV swabs have the potential to promote regular cervical cancer screening among TM individuals and to narrow screening disparities. Work is ongoing to establish swab accuracy and develop shared decision-making tools.
Winer, Rachel L; Tiro, Jasmin A; Miglioretti, Diana L; Thayer, Chris; Beatty, Tara; Lin, John; Gao, Hongyuan; Kimbel, Kilian; Buist, Diana S M
2018-01-01
Women who delay or do not attend Papanicolaou (Pap) screening are at increased risk for cervical cancer. Trials in countries with organized screening programs have demonstrated that mailing high-risk (hr) human papillomavirus (HPV) self-sampling kits to under-screened women increases participation, but U.S. data are lacking. HOME is a pragmatic randomized controlled trial set within a U.S. integrated healthcare delivery system to compare two programmatic approaches for increasing cervical cancer screening uptake and effectiveness in under-screened women (≥3.4years since last Pap) aged 30-64years: 1) usual care (annual patient reminders and ad hoc outreach by clinics) and 2) usual care plus mailed hrHPV self-screening kits. Over 2.5years, eligible women were identified through electronic medical record (EMR) data and randomized 1:1 to the intervention or control arm. Women in the intervention arm were mailed kits with pre-paid envelopes to return samples to the central clinical laboratory for hrHPV testing. Results were documented in the EMR to notify women's primary care providers of appropriate follow-up. Primary outcomes are detection and treatment of cervical neoplasia. Secondary outcomes are cervical cancer screening uptake, abnormal screening results, and women's experiences and attitudes towards hrHPV self-sampling and follow-up of hrHPV-positive results (measured through surveys and interviews). The trial was designed to evaluate whether a programmatic strategy incorporating hrHPV self-sampling is effective in promoting adherence to the complete screening process (including follow-up of abnormal screening results and treatment). The objective of this report is to describe the rationale and design of this pragmatic trial. Copyright © 2017 Elsevier Inc. All rights reserved.
Wisner, Katherine L; Sit, Dorothy K Y; McShea, Mary C; Rizzo, David M; Zoretich, Rebecca A; Hughes, Carolyn L; Eng, Heather F; Luther, James F; Wisniewski, Stephen R; Costantino, Michelle L; Confer, Andrea L; Moses-Kolko, Eydie L; Famy, Christopher S; Hanusa, Barbara H
2013-05-01
The period prevalence of depression among women is 21.9% during the first postpartum year; however, questions remain about the value of screening for depression. To screen for depression in postpartum women and evaluate positive screen findings to determine the timing of episode onset, rate and intensity of self-harm ideation, and primary and secondary DSM-IV disorders to inform treatment and policy decisions. Sequential case series of women who recently gave birth. Urban academic women's hospital. During the maternity hospitalization, women were offered screening at 4 to 6 weeks post partum by telephone. Screen-positive women were invited to undergo psychiatric evaluations in their homes. A positive screen finding was an Edinburgh Postnatal Depression Scale (EPDS) score of 10 or higher. Self-harm ideation was assessed on EPDS item 10: "The thought of harming myself has occurred to me" (yes, quite often; sometimes; hardly ever; never). Screen-positive women underwent evaluation with the Structured Clinical Interview for DSM-IV for Axis I primary and secondary diagnoses. Ten thousand mothers underwent screening, with positive findings in 1396 (14.0%); of these, 826 (59.2%) completed the home visits and 147 (10.5%) completed a telephone diagnostic interview. Screen-positive women were more likely to be younger, African American, publicly insured, single, and less well educated. More episodes began post partum (40.1%), followed by during pregnancy (33.4%) and before pregnancy (26.5%). In this population, 19.3% had self-harm ideation. All mothers with the highest intensity of self-harm ideation were identified with the EPDS score of 10 or higher. The most common primary diagnoses were unipolar depressive disorders (68.5%), and almost two-thirds had comorbid anxiety disorders. A striking 22.6% had bipolar disorders. The most common diagnosis in screen-positive women was major depressive disorder with comorbid generalized anxiety disorder. Strategies to differentiate women with bipolar from unipolar disorders are needed. clinicaltrials.gov Identifier: NCT00282776.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Starrett, C. E.; Saumon, D.
Here, we present an approximation for calculating the equation of state (EOS) of warm and hot dense matter that is built on the previously published pseudoatom molecular dynamics (PAMD) model of dense plasmas [Starrett et al., Phys. Rev. E 91, 013104 (2015)]. And while the EOS calculation with PAMD was previously limited to orbital-free density functional theory (DFT), the new approximation presented here allows a Kohn-Sham DFT treatment of the electrons. The resulting EOS thus includes a quantum mechanical treatment of the electrons with a self-consistent model of the ionic structure, while remaining tractable at high temperatures. The method ismore » validated by comparisons with pressures from ab initio simulations of Be, Al, Si, and Fe. The EOS in the Thomas-Fermi approximation shows remarkable thermodynamic consistency over a wide range of temperatures for aluminum. We also calculate the principal Hugoniots of aluminum and silicon up to 500 eV. We find that the ionic structure of the plasma has a modest effect that peaks at temperatures of a few eV and that the features arising from the electronic structure agree well with ab initio simulations.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fukuda, Ryoichi, E-mail: fukuda@ims.ac.jp; Ehara, Masahiro; Elements Strategy Initiative for Catalysts and Batteries
2015-12-31
The effects from solvent environment are specific to the electronic states; therefore, a computational scheme for solvent effects consistent with the electronic states is necessary to discuss electronic excitation of molecules in solution. The PCM (polarizable continuum model) SAC (symmetry-adapted cluster) and SAC-CI (configuration interaction) methods are developed for such purposes. The PCM SAC-CI adopts the state-specific (SS) solvation scheme where solvent effects are self-consistently considered for every ground and excited states. For efficient computations of many excited states, we develop a perturbative approximation for the PCM SAC-CI method, which is called corrected linear response (cLR) scheme. Our test calculationsmore » show that the cLR PCM SAC-CI is a very good approximation of the SS PCM SAC-CI method for polar and nonpolar solvents.« less
Elizondo-Aguilera, L F; Zubieta Rico, P F; Ruiz-Estrada, H; Alarcón-Waess, O
2014-11-01
A self-consistent generalized Langevin-equation theory is proposed to describe the self- and collective dynamics of a liquid of linear Brownian particles. The equations of motion for the spherical harmonics projections of the collective and self-intermediate-scattering functions, F_{lm,lm}(k,t) and F_{lm,lm}^{S}(k,t), are derived as a contraction of the description involving the stochastic equations of the corresponding tensorial one-particle density n_{lm}(k,t) and the translational (α=T) and rotational (α=R) current densities j_{lm}^{α}(k,t). Similar to the spherical case, these dynamic equations require as an external input the equilibrium structural properties of the system contained in the projections of the static structure factor, denoted by S_{lm,lm}(k). Complementing these exact equations with simple (Vineyard-like) approximate relations for the collective and the self-memory functions we propose a closed self-consistent set of equations for the dynamic properties involved. In the long-time asymptotic limit, these equations become the so-called bifurcation equations, whose solutions (the nonergodicity parameters) can be written, extending the spherical case, in terms of one translational and one orientational scalar dynamic order parameter, γ_{T} and γ_{R}, which characterize the possible dynamical arrest transitions of the system. As a concrete illustrative application of this theory we determine the dynamic arrest diagram of the dipolar hard-sphere fluid. In qualitative agreement with mode coupling theory, the present self-consistent equations also predict three different regions in the state space spanned by the macroscopic control parameters η (volume fraction) and T* (scaled temperature): a region of fully ergodic states, a region of mixed states, in which the translational degrees of freedom become arrested while the orientational degrees of freedom remain ergodic, and a region of fully nonergodic states.
Health beliefs of blue collar workers. Increasing self efficacy and removing barriers.
Wilson, S; Sisk, R J; Baldwin, K A
1997-05-01
The study compared the health beliefs of participants and non-participants in a blood pressure and cholesterol screening held at the worksite. A cross sectional, ex-post facto design was used. Questionnaires measuring health beliefs related to cardiac screening and prevention of cardiac problems were distributed to a convenience sample of 200 blue-collar workers in a large manufacturing plant in the Midwest. One hundred fifty-one (75.5%) completed questionnaires were returned, of which 45 had participated in cardiac worksite screening in the past month. A multivariate analysis of variance was used to analyze data. Participants perceived significantly fewer barriers to cardiac screening and scored significantly higher on self efficacy than non-participants. These findings concur with other studies identifying barriers and self efficacy as important predictors of health behavior. Occupational health nurses' efforts are warranted to reduce barriers and improve self efficacy by advertising screenings, scheduling them at convenient times and locations, assuring privacy, and keeping time inconvenience to a minimum.
Arrossi, Silvina; Ramos, Silvina; Straw, Cecilia; Thouyaret, Laura; Orellana, Liliana
2016-08-19
HPV test self-collection has been shown to reduce barriers to cervical screening and increase uptake. However, little is known about women's preferences when given the choice between self-collected and clinician-collected tests. This paper aims to describe experiences with HPV self-collection among women in Jujuy, the first Argentinean province to have introduced HPV testing as the primary screening method, provided free of cost in all public health centers. Between July and December 2012, data on acceptability of HPV self-collection and several social variables including past screening were collected from 2616 self-collection accepters and 433 non-accepters, and were analyzed using multivariate regression. In addition, in-depth interviews (n = 30) and 2 focus groups were carried out and analyzed using thematic analysis. Quantitative findings indicate that main reasons for choosing self-collection are those reducing barriers related to women's roles of responsibility for domestic work and work/family organization, and to health care services' organization. No social variables were significantly associated with acceptability. Among those who preferred clinician-collection, the main reasons were trust in health professionals and fear of hurting themselves. Qualitative findings also showed that self-collection allows women to overcome barriers related to the health system (i.e. long wait times), without sacrificing time devoted to work/domestic responsibilities. Findings have implications for self-collection recommendations, as they show it is the preferred method when women are given the choice, even if they are not screening non-attenders. Findings also highlight the importance of incorporating women's needs/preferences in HPV screening recommendations.
Colonoscopy demand and capacity in New Hampshire.
Butterly, Lynn; Olenec, Christopher; Goodrich, Martha; Carney, Patricia; Dietrich, Allen
2007-01-01
Screening for colorectal cancer has been clearly shown to decrease the incidence and mortality from this disease. Accurate information about the demand and capacity for screening, particularly with colonoscopy, is critical in planning screening strategies. National assessments have recently begun; estimates of smaller geographic regions should improve the accuracy of national estimates, as well as inform strategies for individual states. This study evaluates the demand and capacity for colonoscopy in the state of New Hampshire. All endoscopy sites in the state of New Hampshire were contacted to determine their number of endoscopists, monthly colonoscopies, and estimates of the percentage of colonoscopy done for screening. Barriers to increasing current capacity were also assessed. The capacity estimates were compared to demand estimates based on population census figures. Data were collected in 2003 to 2004 and analyzed in 2005 to 2006. One hundred fourteen endoscopists at 36 centers performed 49,352 colonoscopies in 2002, an average of 39 to 43 total monthly colonoscopies per endoscopist. Approximately 60% were estimated to have been done for screening. Estimated demand was approximately twice the available capacity for screening and surveillance. The impact of factors such as compliance, percent screening, and population growth were assessed to inform future screening strategies. In 2002, demand for screening colonoscopy in New Hampshire for patients aged more than 50 years was approximately twice the available capacity. However, if the assessed screening capacity of 2002 were to increase by 20%, combined with a target of 60% population compliance with screening as an initial goal, the demand for colonoscopy in New Hampshire would be met.
Savitz, Samuel T; Stearns, Sally C; Zhou, Lei; Thudium, Emily; Alburikan, Khalid A; Tran, Richard; Rodgers, Jo E
2017-05-01
Medicare Part D claims indicate medication purchased, but people who are not fully adherent may extend prescription use beyond the interval prescribed. This study assessed concordance between Part D claims and medication possession at a study visit in relation to self-reported medication adherence. We matched Part D claims for 6 common medications to medications brought to a study visit in 2011-2013 for the Atherosclerosis Risk in Communities study. The combined data consisted of 3027 medication events (claims, medications possessed, or both) for 2099 Atherosclerosis Risk in Communities study participants. Multinomial logistic regression estimated the association of concordance (visit only, Part D only, or both) with self-reported medication adherence while controlling for sociodemographic characteristics, veteran status, and availability under Generic Drug Discount Programs. Relative to participants with high adherence, medication events for participants with low adherence were approximately 25 percentage points less likely to match and more likely to be visit only (P<0.001). The results were similar but smaller in magnitude (approximately 2-3 percentage points) for participants with medium adherence. Compared with females, medication events for male veterans were approximately 11 percentage points less likely to match and more likely to be visit only. Events for medications available through Generic Drug Discount Programs were 3 percentage points more likely to be visit only. Part D claims were substantially less likely to be concordant with medications possessed at study visit for participants with low self-reported adherence. This result supports the construction of adherence proxies such as proportion days covered using Part D claims.
Electronic structures of of PuX (X=S, Se, Te)
NASA Astrophysics Data System (ADS)
Maehira, Takahiro; Sakai, Eijiro; Tatetsu, Yasutomi
2013-08-01
We have calculated the energy band structures and the Fermi surfaces of PuS, PuSe, and PuTe by using a self-consistent relativistic linear augmented-plane-wave method with the exchange and correlation potential in the local density approximation. In general, the energy bands near the Fermi level are mainly caused by the hybridization between the Pu 5 f and the monochalcogenide p electrons. The obtained main Fermi surfaces consisted of two hole sheets and one electron sheet, which were constructed from the band having both the Pu 5 f state and the monochalcogenide p state.
NASA Astrophysics Data System (ADS)
Panda, Rudrashish; Sahu, Sivabrata; Rout, G. C.
2017-05-01
We communicate here a tight binding theoretical model study of the band filling effect on the charge gap in graphene-on-substrate. The Hamiltonian consists of nearest neighbor electron hopping and substrate induced gap. Besides this the Coulomb interaction is considered here within mean-field approximation in the paramagnetic limit. The electron occupancies at two sublattices are calculated by Green's function technique and are solved self consistently. Finally the charge gap i.e. Δ ¯=U [ < na > -< nb > ] is calculated and computed numerically. The results are reported.
Wang, Shengyu; Gong, Wei; Tian, Yao
2016-05-01
Chronic obstructive pulmonary disease (COPD) is projected to be the third leading cause of death by 2020. Early detection and screening may alter the course and prognosis associated with lung disease. We investigated the effectiveness of a voluntary public lung function screening program and factors that had a predictive value for asymptomatic COPD in Xi'an, China. Pulmonary function testing (PFT) was conducted on volunteers recruited from four community centers in Xi'an, China, between July and August 2012. Participants underwent three forced vital capacity maneuvers. The maneuver with the best forced expiratory volume in first second was retained. Participants filled out a medical history and environmental exposure survey before undergoing the PFT. Patients who self-reported lung disease on the health survey were excluded from the analysis. Logistical regression was used to determine associations with airway obstruction. A total of 803 volunteers participated in this study, and 33 subjects were excluded as the participants did not meet the requirements of PFT. Of the 770 volunteers, 44 participants had been diagnosed with chronic respiratory diseases previously, and 144 participants (18.7%) met COPD criteria. Four hundred forty-four participants did not self-report any respiratory symptoms, and the remaining 282 participants self-reported respiratory symptoms. Of the asymptomatic participants, 98 volunteers had PFT results that were consistent with COPD and 68.1% of asymptomatic participants were undiagnosed. A greater percentage of women than men had moderate or severe airway obstruction (p = 0.004).Only smoking status (odds ratio = 2.64, 95% confidence interval 1.20-6.04) was associated with asymptomatic COPD. Voluntary public lung function screening programs in China are likely to identify a large number of undiagnosed, asymptomatic COPD. Smoking status is associated with airway obstruction and a greater percentage of women than men had moderate or severe airway obstruction. © The Author(s) 2016.
Yamaguchi, Manako; Sekine, Masayuki; Kudo, Risa; Adachi, Sosuke; Ueda, Yutaka; Miyagi, Etsuko; Hara, Megumi; Hanley, Sharon J B; Enomoto, Takayuki
2018-05-25
Japan has no national vaccine registry and approximately 1700 municipalities manage the immunization records independently. In June 2013, proactive recommendations for the human papillomavirus (HPV) vaccine were suspended after unconfirmed reports of adverse events following immunization in the media, despite no vaccine safety signal having been raised. Furthermore, studies assessing HPV vaccine safety and effectiveness published post suspension are predominantly based on self-reported information. Our aim was to examine the accuracy of self-reported vaccination status compared with official municipal records. Participants were women aged 20-22 yrs, who were attending for cervical screening in Niigata city. Among the 1230 eligible registrants, vaccine uptake, defined as any dose, was 75.0% and 77.2% according to a self-reported questionnaire and municipal records, respectively. The accuracy rate of self-reported information was as follows: positive predictive value (PPV) was 87.7%; negative predictive value (NPV) was 54.5%; sensitivity was 85.2%; and specificity was 59.8%. The validity of self-reported information was only moderate (Kappa statistic = 0.44, 95% confidence interval 0.37-0.50). This combined with the low NPV may lead to reduced estimation of effectiveness and safety. A more reliable method, such as a national HPV vaccine registry, needs to be established for assessing HPV immunization status in Japan. Copyright © 2018. Published by Elsevier B.V.
Vahabi, Mandana; Lofters, Aisha
2016-08-24
Canada has observed significant decreases in incidence and mortality of cervical cancer in recent decades, and this has been attributed to appropriate screening (i.e., the Pap test). However, certain subgroups including Muslim immigrants show higher rates of cervical cancer mortality despite their lower incidence. Low levels of screening have been attributed to such barriers as lack of a family physician, inconvenient clinic hours, having a male physician, and cultural barriers (e.g., modesty, language). HPV self -sampling helps to alleviate many of these barriers. However, little is known about the acceptability of this evidence-based strategy among Muslim women. This study explored Muslim immigrant women's views on cervical cancer screening and the acceptability of HPV self-sampling. An exploratory community-based mixed methods design was used. A convenience sample of 30 women was recruited over a 3-month period (June-August 2015) in the Greater Toronto Area. All were between 21 and 69 years old, foreign-born, self-identified as Muslim, and had good knowledge of English. Data were collected through focus groups. This study provides critical insights about the importance of religious and cultural beliefs in shaping the daily and health care experiences of Muslim women and their cancer screening decisions. Our study showed the deterring impact of beliefs and health practices in home countries on Muslim immigrant women's utilization of screening services. Limited knowledge about cervical cancer and screening guidelines and need for provision of culturally appropriate sexual health information were emphasized. The results revealed that HPV self-sampling provides a favorable alternative model of care to the traditional provider-administered Pap testing for this population. To enhance Muslim immigrant women screening uptake, efforts should made to increase 1) their knowledge of the Canadian health care system and preventive services at the time of entry to Canada, and 2) access to culturally sensitive education programs, female health professionals, and alternative modes of screening like HPV self-sampling. Health professionals need to take an active role in offering screening during health encounters, be educated about sexual health communication with minority women, and be aware of the detrimental impact of preconceived assumptions about sexual activity of Muslim women.
Local moment relaxation in heavy-fermion compounds
DOE Office of Scientific and Technical Information (OSTI.GOV)
Simanek, E.; Sasahara, K.
1987-02-01
The Korringa relaxation rate for a local moment of an impurity in a heavy fermion compound is calculated using the model of Yoshimori and Kasai. Consistent with the recent ESR data for local moments in UBe/sub 13/, the relaxation rate is found to be unaffected by the heavy fermion renormalizations. This result can be traced to the single-site approximation and the weak k dependence of the conduction electron self-energy.
Wave fluctuations in the system with some Yang-Mills condensates
DOE Office of Scientific and Technical Information (OSTI.GOV)
Prokhorov, G., E-mail: zhoraprox@yandex.ru; Pasechnik, R., E-mail: Roman.Pasechnik@thep.lu.se; Vereshkov, G., E-mail: gveresh@gmail.com
2016-12-15
Self-consistent dynamics of non-homogeneous fluctuations and homogeneous and isotropic condensate of Yang–Mills fields was investigated in zero, linear and quasilinear approximations over the wave modes in the framework of N = 4 supersymmetric model in Hamilton gauge in quasiclassical theory. The models with SU(2), SU(3) and SU(4) gauge groups were considered. Particle production effect and effect of generation of longitudinal oscillations were obtained.
Disorder and superfluid density in overdoped cuprate superconductors
NASA Astrophysics Data System (ADS)
Lee-Hone, N. R.; Dodge, J. S.; Broun, D. M.
2017-07-01
We calculate superfluid density for a dirty d -wave superconductor. The effects of impurity scattering are treated within the self-consistent t -matrix approximation, in weak-coupling BCS theory. Working from a realistic tight-binding parametrization of the Fermi surface, we find a superfluid density that is both correlated with Tc and linear in temperature, in good correspondence with recent experiments on overdoped La2 -xSrxCuO4 .
Anderson-Bill, Eileen Smith; Winett, Richard A; Wojcik, Janet R
2011-03-17
The Internet is a trusted source of health information for growing majorities of Web users. The promise of online health interventions will be realized with the development of purely online theory-based programs for Web users that are evaluated for program effectiveness and the application of behavior change theory within the online environment. Little is known, however, about the demographic, behavioral, or psychosocial characteristics of Web-health users who represent potential participants in online health promotion research. Nor do we understand how Web users' psychosocial characteristics relate to their health behavior-information essential to the development of effective, theory-based online behavior change interventions. This study examines the demographic, behavioral, and psychosocial characteristics of Web-health users recruited for an online social cognitive theory (SCT)-based nutrition, physical activity, and weight gain prevention intervention, the Web-based Guide to Health (WB-GTH). Directed to the WB-GTH site by advertisements through online social and professional networks and through print and online media, participants were screened, consented, and assessed with demographic, physical activity, psychosocial, and food frequency questionnaires online (taking a total of about 1.25 hours); they also kept a 7-day log of daily steps and minutes walked. From 4700 visits to the site, 963 Web users consented to enroll in the study: 83% (803) were female, participants' mean age was 44.4 years (SD 11.03 years), 91% (873) were white, and 61% (589) were college graduates; participants' median annual household income was approximately US $85,000. Participants' daily step counts were in the low-active range (mean 6485.78, SD 2352.54) and overall dietary levels were poor (total fat g/day, mean 77.79, SD 41.96; percent kcal from fat, mean 36.51, SD 5.92; fiber g/day, mean 17.74, SD 7.35; and fruit and vegetable servings/day, mean 4.03, SD 2.33). The Web-health users had good self-efficacy and outcome expectations for health behavior change; however, they perceived little social support for making these changes and engaged in few self-regulatory behaviors. Consistent with SCT, theoretical models provided good fit to Web-users' data (root mean square error of the approximation [RMSEA] < .05). Perceived social support and use of self-regulatory behaviors were strong predictors of physical activity and nutrition behavior. Web users' self-efficacy was also a good predictor of healthier levels of physical activity and dietary fat but not of fiber, fruits, and vegetables. Social support and self-efficacy indirectly predicted behavior through self-regulation, and social support had indirect effects through self-efficacy. Results suggest Web-health users visiting and ultimately participating in online health interventions may likely be middle-aged, well-educated, upper middle class women whose detrimental health behaviors put them at risk of obesity, heart disease, some cancers, and diabetes. The success of Internet physical activity and nutrition interventions may depend on the extent to which they lead users to develop self-efficacy for behavior change, but perhaps as important, the extent to which these interventions help them garner social-support for making changes. Success of these interventions may also depend on the extent to which they provide a platform for setting goals, planning, tracking, and providing feedback on targeted behaviors.
Winett, Richard A; Wojcik, Janet R
2011-01-01
Background The Internet is a trusted source of health information for growing majorities of Web users. The promise of online health interventions will be realized with the development of purely online theory-based programs for Web users that are evaluated for program effectiveness and the application of behavior change theory within the online environment. Little is known, however, about the demographic, behavioral, or psychosocial characteristics of Web-health users who represent potential participants in online health promotion research. Nor do we understand how Web users’ psychosocial characteristics relate to their health behavior—information essential to the development of effective, theory-based online behavior change interventions. Objective This study examines the demographic, behavioral, and psychosocial characteristics of Web-health users recruited for an online social cognitive theory (SCT)-based nutrition, physical activity, and weight gain prevention intervention, the Web-based Guide to Health (WB-GTH). Methods Directed to the WB-GTH site by advertisements through online social and professional networks and through print and online media, participants were screened, consented, and assessed with demographic, physical activity, psychosocial, and food frequency questionnaires online (taking a total of about 1.25 hours); they also kept a 7-day log of daily steps and minutes walked. Results From 4700 visits to the site, 963 Web users consented to enroll in the study: 83% (803) were female, participants’ mean age was 44.4 years (SD 11.03 years), 91% (873) were white, and 61% (589) were college graduates; participants’ median annual household income was approximately US $85,000. Participants’ daily step counts were in the low-active range (mean 6485.78, SD 2352.54) and overall dietary levels were poor (total fat g/day, mean 77.79, SD 41.96; percent kcal from fat, mean 36.51, SD 5.92; fiber g/day, mean 17.74, SD 7.35; and fruit and vegetable servings/day, mean 4.03, SD 2.33). The Web-health users had good self-efficacy and outcome expectations for health behavior change; however, they perceived little social support for making these changes and engaged in few self-regulatory behaviors. Consistent with SCT, theoretical models provided good fit to Web-users’ data (root mean square error of the approximation [RMSEA] < .05). Perceived social support and use of self-regulatory behaviors were strong predictors of physical activity and nutrition behavior. Web users’ self-efficacy was also a good predictor of healthier levels of physical activity and dietary fat but not of fiber, fruits, and vegetables. Social support and self-efficacy indirectly predicted behavior through self-regulation, and social support had indirect effects through self-efficacy. Conclusions Results suggest Web-health users visiting and ultimately participating in online health interventions may likely be middle-aged, well-educated, upper middle class women whose detrimental health behaviors put them at risk of obesity, heart disease, some cancers, and diabetes. The success of Internet physical activity and nutrition interventions may depend on the extent to which they lead users to develop self-efficacy for behavior change, but perhaps as important, the extent to which these interventions help them garner social-support for making changes. Success of these interventions may also depend on the extent to which they provide a platform for setting goals, planning, tracking, and providing feedback on targeted behaviors. PMID:21441100
NASA Astrophysics Data System (ADS)
Böttger, B.; Eiken, J.; Apel, M.
2009-10-01
Performing microstructure simulation of technical casting processes suffers from the strong interdependency between latent heat release due to local microstructure formation and heat diffusion on the macroscopic scale: local microstructure formation depends on the macroscopic heat fluxes and, in turn, the macroscopic temperature solution depends on the latent heat release, and therefore on the microstructure formation, in all parts of the casting. A self-consistent homoenthalpic approximation to this micro-macro problem is proposed, based on the assumption of a common enthalpy-temperature relation for the whole casting which is used for the description of latent heat production on the macroscale. This enthalpy-temperature relation is iteratively obtained by phase-field simulations on the microscale, thus taking into account the specific morphological impact on the latent heat production. This new approach is discussed and compared to other approximations for the coupling of the macroscopic heat flux to complex microstructure models. Simulations are performed for the binary alloy Al-3at%Cu, using a multiphase-field solidification model which is coupled to a thermodynamic database. Microstructure formation is simulated for several positions in a simple model plate casting, using a one-dimensional macroscopic temperature solver which can be directly coupled to the microscopic phase-field simulation tool.
Yang, Yang; Yu, Haibo; York, Darrin; Cui, Qiang; Elstner, Marcus
2007-10-25
The standard self-consistent-charge density-functional-tight-binding (SCC-DFTB) method (Phys. Rev. B 1998, 58, 7260) is derived by a second-order expansion of the density functional theory total energy expression, followed by an approximation of the charge density fluctuations by charge monopoles and an effective damped Coulomb interaction between the atomic net charges. The central assumptions behind this effective charge-charge interaction are the inverse relation of atomic size and chemical hardness and the use of a fixed chemical hardness parameter independent of the atomic charge state. While these approximations seem to be unproblematic for many covalently bound systems, they are quantitatively insufficient for hydrogen-bonding interactions and (anionic) molecules with localized net charges. Here, we present an extension of the SCC-DFTB method to incorporate third-order terms in the charge density fluctuations, leading to chemical hardness parameters that are dependent on the atomic charge state and a modification of the Coulomb scaling to improve the electrostatic treatment within the second-order terms. These modifications lead to a significant improvement in the description of hydrogen-bonding interactions and proton affinities of biologically relevant molecules.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Skalozub, A.S.; Tsaune, A.Ya.
1994-12-01
A new approach for analyzing the highly excited vibration-rotation (VR) states of nonrigid molecules is suggested. It is based on the separation of the vibrational and rotational terms in the molecular VR Hamiltonian by introducing periodic auxiliary fields. These fields transfer different interactions within a molecule and are treated in terms of the mean-field approximation. As a result, the solution of the stationary Schroedinger equation with the VR Hamiltonian amounts to a quantization of the Berry phase in a problem of the molecular angular-momentum motion in a certain periodic VR field (rotational problem). The quantization procedure takes into account themore » motion of the collective vibrational variables in the appropriate VR potentials (vibrational problem). The quantization rules, the mean-field configurations of auxiliary interactions, and the solutions to the Schrodinger equations for the vibrational and rotational problems are self-consistently connected with one another. The potentialities of the theory are demonstrated by the bending-rotation interaction modeled by the Bunker-Landsberg potential function in the H{sub 2} molecule. The calculations are compared with both the results of the exact computations and those of other approximate methods. 32 refs., 4 tabs.« less
Shiroff, Jennifer J; Gregoski, Mathew J
2017-06-01
Measurement of recessive carrier screening attitudes related to conception and pregnancy is necessary to determine current acceptance, and whether behavioral intervention strategies are needed in clinical practice. To evaluate quantitative survey instruments to measure patient attitudes regarding genetic carrier testing prior to conception and pregnancy databases examining patient attitudes regarding genetic screening prior to conception and pregnancy from 2003-2013 were searched yielding 344 articles; eight studies with eight instruments met criteria for inclusion. Data abstraction on theoretical framework, subjects, instrument description, scoring, method of measurement, reliability, validity, feasibility, level of evidence, and outcomes was completed. Reliability information was provided in five studies with an internal consistency of Cronbach's α >0.70. Information pertaining to validity was presented in three studies and included construct validity via factor analysis. Despite limited psychometric information, these questionnaires are self-administered and can be briefly completed, making them a feasible method of evaluation.
De Ryck, R; Struelens, M J; Serruys, E
1994-01-01
Four screens for the rapid (4 to 6 h) biochemical detection of pathogens from enteric isolation media are described. The Salmonella screen consisted of Kligler iron agar (KIA), motility-indole-urea-tryptophan-deamination semisolid medium (MIU-TDA), and the o-nitrophenyl-beta-D-galactopyranoside (ONPG) test; the Shigella screen consisted of KIA, MIU-TDA, the ONPG test, and the lysine decarboxylation-indole test; the Yersinia screen consisted of a rhamnose broth; the Aeromonas screen consisted of a xylose agar plate. When tested on 2,102 fresh isolates and 71 stock strains, the screens correctly detected 212 enteric pathogens (sensitivity, 100%), with a specificity of 98.1%. PMID:8077408
Cuaresma, Charlene F; Sy, Angela U; Nguyen, Tung T; Ho, Reginald C S; Gildengorin, Ginny L; Tsoh, Janice Y; Jo, Angela M; Tong, Elisa K; Kagawa-Singer, Marjorie; Stewart, Susan L
2018-04-01
Filipino colorectal cancer (CRC) screening rates fall below Healthy People 2020 goals. In this study, the authors explore whether a lay health educator (LHE) approach can increase CRC screening among Filipino Americans ages 50 to 75 years in Hawai'i. A cluster randomized controlled trial from 2012 through 2015 compared an intervention, which consisted of LHEs delivering 2 education sessions and 2 telephone follow-up calls on CRC screening plus a CRC brochure versus an attention control, in which 2 lectures and 2 follow-up calls on nutrition and physical activity plus a CRC brochure were provided. The primary outcome was change in self-reported ever receipt of CRC screening at 6 months. Among 304 participants (77% women, 86% had > 10 years of residence in the United States), the proportion of participants who reported ever having received CRC screening increased significantly in the intervention group (from 80% to 89%; P = .0003), but not in the control group (from 73% to 74%; P = .60). After covariate adjustment, there was a significant intervention effect (odds ratio, 1.9; 95% confidence interval, 1.0-3.5). There was no intervention effect on up-to-date screening. This first randomized controlled trial for CRC screening among Hawai'i's Filipinos used an LHE intervention with mixed, but promising, results. Cancer 2018;124:1535-42. © 2018 American Cancer Society. © 2018 American Cancer Society.
Entiat 4Mile WELLs Completion Report, 2006.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Malinowksi, Richard
2007-01-01
The Entiat 4-mile Wells (Entiat 4-mile) project is located in the Entiat subbasin and will benefit Upper Columbia steelhead, spring Chinook and bull trout. The goal of this project is to prevent juvenile fish from being diverted into an out-of-stream irrigation system and to eliminate impacts due to the annual maintenance of an instream pushup dam. The objectives include eliminating a surface irrigation diversion and replacing it with two wells, which will provide Bonneville Power Administration (BPA) and the Bureau of Reclamation (Reclamation) with a Federal Columbia River Power System (FCRPS) BiOp metric credit of one. Wells were chosen overmore » a new fish screen based on biological benefits and costs. Long-term biological benefits are provided by completely eliminating the surface diversion and the potential for fish entrainment in a fish screen. Construction costs for a new fish screen were estimated at $150,000, which does not include other costs associated with implementing and maintaining a fish screening project. Construction costs for a well were estimated at $20,000 each. The diversion consisted of a pushup dam that diverted water into an off-channel pond. Water was then pumped into a pressurized system for irrigation. There are 3 different irrigators who used water from this surface diversion, and each has multiple water right claims totaling approximately 5 cfs. Current use was estimated at 300 gallons per minute (approximately 0.641 cfs). Some irrigated acreage was taken out of orchard production less than 5 years ago. Therefore, approximately 6.8 acre-feet will be put into the State of Washington Trust Water Right program. No water will be set aside for conservation savings. The construction of the two irrigation wells for three landowners was completed in September 2006. The Lower Well (Tippen/Wick) will produce up to 175 gpm while the Upper Well (Griffith) will produce up to 275 gpm during the irrigation season. The eight inch diameter wells were developed to a depth of 75 feet and 85 feet, respectively, and will be pumped with Submersible Turbine pumps. The irrigation wells have been fitted with new electric boxes and Siemens flowmeters (MAG8000).« less
Thomas, Brittany; Fitzpatrick, Sandra; Sidani, Souraya; Gucciardi, Enza
2018-06-01
Routine food insecurity screening is recommended in diabetes care to inform more tailored interventions that better support diabetes self-management among food-insecure patients. This pilot study explored the acceptability and feasibility of a food insecurity screening initiative within a diabetes care setting in Toronto. A systematic literature review informed the development of a food insecurity screening initiative to help health-care providers tailor diabetes management plans and better support food-insecure patients with type 2 diabetes. Interviews with 10 patients and a focus group with 15 care providers elicited feedback on the relevance and acceptance of the food insecurity screening questions and a care algorithm. Subsequently, 5 care providers at 4 sites implemented the screening initiative over 2 weeks, screening 33 patients. After implementation, 7 patients and 5 care providers were interviewed to assess the acceptability and feasibility of the screening initiative. Our findings demonstrate that patients are willing to share their experiences of food insecurity, despite the sensitivity of this topic. Screening elicited information about how patients cope with food insecurity and how this affects their ability to self-manage diabetes. Care providers found this information helpful in directing their care and support for patients. Using a standardized, respectful method of assessing food insecurity can better equip health-care providers to support food-insecure patients with diabetes self-management. Further evaluation of this initiative is needed to determine how food insecurity screening can affect patients' self-management and related health outcomes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.
McCabe, Sean Esteban; West, Brady T; Boyd, Carol J
2013-05-01
The objective of this study was to examine the prevalence and patterns associated with past-year medical use, medical misuse, and nonmedical use of prescription opioids (NMUPO) among adolescents over a 2-year time period and to examine substance abuse, sleeping problems, and physical pain symptoms associated with these patterns of medical use, medical misuse, and NMUPO. A Web-based survey was self-administered by a longitudinal sample of 2050 middle and high school students in 2009-2010 (Year 1) and again in 2010-2011 (Year 2). The study was set in 2 southeastern Michigan school districts. The longitudinal sample consisted of 50% females, 67% Whites, 28% African-Americans, and 5% from other racial/ethnic categories. Main outcome measures were past-year medical use, medical misuse, and NMUPO. Of those reporting appropriate medical use of prescription opioids in Year 1, approximately 34% continued medical use in Year 2. Of those reporting past-year NMUPO in Year 1, approximately 25% continued NMUPO in Year 2. Appropriate medical use and NMUPO for pain relief was more prevalent among girls than boys. Multiple logistic regression analyses indicated that the odds of a positive screen for substance abuse in Year 2 were greater for adolescents who reported medical misuse or NMUPO for non-pain-relief motives in Year 1 compared with those who did not use prescription opioids. The findings indicate an increased risk for substance abuse among adolescents who report medical misuse or NMUPO for non-pain-relief motives over time. The findings have important clinical implications for interventions to reduce medical misuse and NMUPO among adolescents. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.
General Second-Order Scalar-Tensor Theory and Self-Tuning
NASA Astrophysics Data System (ADS)
Charmousis, Christos; Copeland, Edmund J.; Padilla, Antonio; Saffin, Paul M.
2012-02-01
Starting from the most general scalar-tensor theory with second-order field equations in four dimensions, we establish the unique action that will allow for the existence of a consistent self-tuning mechanism on Friedmann-Lemaître-Robertson-Walker backgrounds, and show how it can be understood as a combination of just four base Lagrangians with an intriguing geometric structure dependent on the Ricci scalar, the Einstein tensor, the double dual of the Riemann tensor, and the Gauss-Bonnet combination. Spacetime curvature can be screened from the net cosmological constant at any given moment because we allow the scalar field to break Poincaré invariance on the self-tuning vacua, thereby evading the Weinberg no-go theorem. We show how the four arbitrary functions of the scalar field combine in an elegant way opening up the possibility of obtaining nontrivial cosmological solutions.
Haltrin, V I
1998-06-20
A self-consistent variant of the two-flow approximation that takes into account strong anisotropy of light scattering in seawater of finite depth and arbitrary turbidity is presented. To achieve an appropriate accuracy, this approach uses experimental dependencies between downward and total mean cosines. It calculates irradiances, diffuse attenuation coefficients, and diffuse reflectances in waters with arbitrary values of scattering, backscattering, and attenuation coefficients. It also takes into account arbitrary conditions of illumination and reflection from the bottom with the Lambertian albedo. This theory can be used for the calculation of apparent optical properties in both open and coastal oceanic waters, lakes, and rivers. It can also be applied to other types of absorbing and scattering medium such as paints, photographic emulsions, and biological tissues.
Unmasking the masked Universe: the 2M++ catalogue through Bayesian eyes
NASA Astrophysics Data System (ADS)
Lavaux, Guilhem; Jasche, Jens
2016-01-01
This work describes a full Bayesian analysis of the Nearby Universe as traced by galaxies of the 2M++ survey. The analysis is run in two sequential steps. The first step self-consistently derives the luminosity-dependent galaxy biases, the power spectrum of matter fluctuations and matter density fields within a Gaussian statistic approximation. The second step makes a detailed analysis of the three-dimensional large-scale structures, assuming a fixed bias model and a fixed cosmology. This second step allows for the reconstruction of both the final density field and the initial conditions at z = 1000 assuming a fixed bias model. From these, we derive fields that self-consistently extrapolate the observed large-scale structures. We give two examples of these extrapolation and their utility for the detection of structures: the visibility of the Sloan Great Wall, and the detection and characterization of the Local Void using DIVA, a Lagrangian based technique to classify structures.
Assembly of collagen into microribbons: effects of pH and electrolytes.
Jiang, Fengzhi; Hörber, Heinrich; Howard, Jonathon; Müller, Daniel J
2004-12-01
Collagen represents the major structural protein of the extracellular matrix. Elucidating the mechanism of its assembly is important for understanding many cell biological and medical processes as well as for tissue engineering and biotechnological approaches. In this work, conditions for the self-assembly of collagen type I molecules on a supporting surface were characterized. By applying hydrodynamic flow, collagen assembled into ultrathin ( approximately 3 nm) highly anisotropic ribbon-like structures coating the entire support. We call these novel collagen structures microribbons. High-resolution atomic force microscopy topographs show that subunits of these microribbons are built by fibrillar structures. The smallest units of these fibrillar structures have cross-sections of approximately 3 x 5nm, consistent with current models of collagen microfibril formation. By varying the pH and electrolyte of the buffer solution during the self-assembly process, the microfibril density and contacts formed within this network could be controlled. Under certain electrolyte compositions the microribbons and microfibers display the characteristic D-periodicity of approximately 65 nm observed for much thicker collagen fibrils. In addition to providing insight into the mechanism of collagen assembly, the ultraflat collagen matrices may also offer novel ways to bio-functionalize surfaces.
Video-Out Projection and Lecture Hall Set-Up. Microcomputing Working Paper Series.
ERIC Educational Resources Information Center
Gibson, Chris
This paper details the considerations involved in determining suitable video projection systems for displaying the Apple Macintosh's screen to large groups of people, both in classrooms with approximately 25 people, and in lecture halls with approximately 250. To project the Mac screen to groups in lecture halls, the Electrohome EDP-57 video…
The agreement between self-reported cervical smear abnormalities and screening programme records.
Canfell, Karen; Beral, Valerie; Green, Jane; Cameron, Rebecca; Baker, Krys; Brown, Anna
2006-01-01
The Million Women Study is a cohort study of women aged 50-64 years in England and Scotland. As a component of the follow-up questionnaire, participants were asked to indicate if they had an abnormal cervical smear in the previous five years. This study compared self-reported cervical abnormalities with screening records obtained from the National Health Service Cervical Screening Programme. For 1944 randomly selected Million Women Study participants in Oxfordshire, screening records were assessed over a six-year period prior to the date of self-reporting. The six-year period was chosen to allow for errors in the recall of timing of abnormal smears. A total of 68 women (3.5%) had a record of at least one equivocal or abnormal smear within the last six years, whereas 49 women (2.5%) self-reported an abnormality. There was a strong trend for an increased probability of self-reporting a history of an abnormal smear as the severity of the recorded abnormality increased (P <0.001). For women with an NHS record of borderline dyskaryosis, mild dyskaryosis, or moderate dyskaryosis/severe dyskaryosis/invasive cancer, the proportions reporting an abnormality were 40%, 58% and 77%, respectively. For women with negative and inadequate smears, the proportion self-reporting an abnormality were 0.6% and 0.7%, respectively. These results indicate that among women whose screening programme records show an abnormal smear, the proportion self-reporting an abnormality increases with the severity of the recorded lesion. Almost all women with a record of negative or inadequate smear(s) correctly interpret the result and do not self-report an abnormality.
A chemical screen for medulloblastoma identifies quercetin as a putative radiosensitizer.
Lagerweij, Tonny; Hiddingh, Lotte; Biesmans, Dennis; Crommentuijn, Matheus H W; Cloos, Jacqueline; Li, Xiao-Nan; Kogiso, Mari; Tannous, Bakhos A; Vandertop, W Peter; Noske, David P; Kaspers, Gertjan J L; Würdinger, Tom; Hulleman, Esther
2016-06-14
Treatment of medulloblastoma in children fails in approximately 30% of patients, and is often accompanied by severe late sequelae. Therefore, more effective drugs are needed that spare normal tissue and diminish long-term side effects. Since radiotherapy plays a pivotal role in the treatment of medulloblastoma, we set out to identify novel drugs that could potentiate the effect of ionizing radiation.Thereto, a small molecule library, consisting of 960 chemical compounds, was screened for its ability to sensitize towards irradiation. This small molecule screen identified the flavonoid quercetin as a novel radiosensitizer for the medulloblastoma cell lines DAOY, D283-med, and, to a lesser extent, D458-med at low micromolar concentrations and irradiation doses used in fractionated radiation schemes. Quercetin did not affect the proliferation of neural precursor cells or normal human fibroblasts. Importantly, in vivo experiments confirmed the radiosensitizing properties of quercetin. Administration of this flavonoid at the time of irradiation significantly prolonged survival in orthotopically xenografted mice. Together, these findings indicate that quercetin is a potent radiosensitizer for medulloblastoma cells that may be a promising lead for the treatment of medulloblastoma in patients.
Tranberg, Mette; Bech, Bodil Hammer; Blaakær, Jan; Jensen, Jørgen Skov; Svanholm, Hans; Andersen, Berit
2016-11-03
The effectiveness of cervical cancer screening programs is challenged by suboptimal participation and coverage. Offering cervico-vaginal self-sampling for human papillomavirus testing (HPV self-sampling) to non-participants can increase screening participation. However, the effect varies substantially among studies, especially depending on the approach used to offer HPV self-sampling. The present trial evaluates the effect on participation in an organized screening program of a HPV self-sampling kit mailed directly to the home of the woman or mailed to the woman's home on demand only, compared with the standard second reminder for regular screening. The CHOiCE trial is a parallel, randomized, controlled, open-label trial. It will include 9327 women aged 30-64 years who are living in the Central Denmark Region and who have not participated in cervical cancer screening after an invitation and one reminder. The women will be equally randomized into three arms: 1) Directly mailed a second reminder including a HPV self-sampling kit; 2) Mailed a second reminder offering a HPV self-sampling kit, to be ordered by e-mail, text message, phone, or through a webpage; and 3) Mailed a second reminder for a practitioner-collected sample (control group). The primary outcome will be the proportion of women in the intervention groups who participate by returning their HPV self-sampling kit or have a practitioner-collected sample compared with the proportion of women who have a practitioner-collected sample in the control group at 90 and 180 days after mail out of the second reminders. Per-protocol and intention-to-treat analyses will be performed. The secondary outcome will be the proportion of women with a positive HPV self-collected sample who attend follow-up testing at 30, 60, or 90 days after mail out of the results. The CHOiCE trial will provide strong and important evidence allowing us to determine if and how HPV self-sampling can be used to increase participation in cervical cancer screening. This trial therefore has the potential to improve prevention and reduce the number of deaths caused by cervical cancer. Current Controlled Trials NCT02680262 . Registered 10 February 2016.
Self-report versus Medical Records for Assessing Cancer-Preventive Services Delivery
Ferrante, Jeanne M.; Ohman-Strickland, Pamela; Hahn, Karissa A.; Hudson, Shawna V.; Shaw, Eric K.; Crosson, Jesse C.; Crabtree, Benjamin F.
2010-01-01
Accurate measurement of cancer-preventive behaviors is important for quality improvement, research studies, and public health surveillance. Findings differ, however, depending on whether patient self-report or medical records are used as the data source. We evaluated concordance between patient self-report and medical records on risk factors, cancer screening, and behavioral counseling among primary care patients. Data from patient surveys and medical records were compared from 742 patients in 25 New Jersey primary care practices participating at baseline in SCOPE (supporting colorectal cancer outcomes through participatory enhancements), an intervention trial to improve colorectal cancer screening in primary care offices. Sensitivity, specificity, and rates of agreement describe concordance between self-report and medical records for risk factors (personal or family history of cancer, smoking), cancer screening (breast, cervical, colorectal, prostate), and counseling (cancer screening recommendations, diet or weight loss, exercise, smoking cessation). Rates of agreement ranged from 41% (smoking cessation counseling) to 96% (personal history of cancer). Cancer screening agreement ranged from 61% (Pap and prostate-specific antigen) to 83% (colorectal endoscopy) with self-report rates greater than medical record rates. Counseling was also reported more frequently by self-report (83% by patient self-report versus 34% by medical record for smoking cessation counseling). Deciding which data source to use will depend on the outcome of interest, whether the data is used for clinical decision making, performance tracking, or population surveillance; the availability of resources; and whether a false positive or a false negative is of more concern. PMID:18990740
Challet-Bouju, Gaëlle; Perrot, Bastien; Romo, Lucia; Valleur, Marc; Magalon, David; Fatséas, Mélina; Chéreau-Boudet, Isabelle; Luquiens, Amandine; Grall-Bronnec, Marie; Hardouin, Jean-Benoit
2016-01-01
Background and aims The aim of this study was to test the screening properties of several combinations of items from gambling scales, in order to harmonize screening of gambling problems in epidemiological surveys. The objective was to propose two brief screening tools (three items or less) for a use in interviews and self-administered questionnaires. Methods We tested the screening properties of combinations of items from several gambling scales, in a sample of 425 gamblers (301 non-problem gamblers and 124 disordered gamblers). Items tested included interview-based items (Pathological Gambling section of the DSM-IV, lifetime history of problem gambling, monthly expenses in gambling, and abstinence of 1 month or more) and self-report items (South Oaks Gambling Screen, Gambling Attitudes, and Beliefs Survey). The gold standard used was the diagnosis of a gambling disorder according to the DSM-5. Results Two versions of the Rapid Screener for Problem Gambling (RSPG) were developed: the RSPG-Interview (RSPG-I), being composed of two interview items (increasing bets and loss of control), and the RSPG-Self-Assessment (RSPG-SA), being composed of three self-report items (chasing, guiltiness, and perceived inability to stop). Discussion and conclusions We recommend using the RSPG-SA/I for screening problem gambling in epidemiological surveys, with the version adapted for each purpose (RSPG-I for interview-based surveys and RSPG-SA for self-administered surveys). This first triage of potential problem gamblers must be supplemented by further assessment, as it may overestimate the proportion of problem gamblers. However, a first triage has the great advantage of saving time and energy in large-scale screening for problem gambling. PMID:27348558
NASA Technical Reports Server (NTRS)
Chamberlain, J. W.
1976-01-01
A perturbation analysis, allowing for temperature and opacity feedbacks, is developed to calculate depletions in the O3 abundance and reductions of stratospheric solar heating that result from increases in NOx concentration. A pair of perturbation coefficients give the reduction in O3 and temperature through the stratosphere for a specified NOx increase. This type of analysis illustrates the tendency for various levels to self-heal when a perturbation occurs. Physical arguments indicate that the expected sign of the climatic effect is correct, with colder surface temperatures produced by reduced magnetic shielding. In addition, four qualitative reasons are suggested for thinking that significant ozone reductions by cosmic ray influxes will lead to an increased terrestrial albedo from stratospheric condensation. In this view, long-term (approximately 10,000 years) climatic changes have resulted from secular geomagnetic variations while shorter (approximately 100 years) excursions are related to changes in solar activity.
Preparation of kinase-biased compounds in the search for lead inhibitors of kinase targets.
Lai, Justine Y Q; Langston, Steven; Adams, Ruth; Beevers, Rebekah E; Boyce, Richard; Burckhardt, Svenja; Cobb, James; Ferguson, Yvonne; Figueroa, Eva; Grimster, Neil; Henry, Andrew H; Khan, Nawaz; Jenkins, Kerry; Jones, Mark W; Judkins, Robert; Major, Jeremy; Masood, Abid; Nally, James; Payne, Helen; Payne, Lloyd; Raphy, Gilles; Raynham, Tony; Reader, John; Reader, Valérie; Reid, Alison; Ruprah, Parminder; Shaw, Michael; Sore, Hannah; Stirling, Matthew; Talbot, Adam; Taylor, Jess; Thompson, Stephen; Wada, Hiroki; Walker, David
2005-05-01
This work describes the preparation of approximately 13,000 compounds for rapid identification of hits in high-throughput screening (HTS). These compounds were designed as potential serine/threonine or tyrosine kinase inhibitors. The library consists of various scaffolds, e.g., purines, oxindoles, and imidazoles, whereby each core scaffold generally includes the hydrogen bond acceptor/donor properties known to be important for kinase binding. Several of these are based upon literature kinase templates, or adaptations of them to provide novelty. The routes to their preparation are outlined. A variety of automation techniques were used to prepare >500 compounds per scaffold. Where applicable, scavenger resins were employed to remove excess reagents and when necessary, preparative high performance liquid chromatography (HPLC) was used for purification. These compounds were screened against an 'in-house' kinase panel. The success rate in HTS was significantly higher than the corporate compound collection. Copyright (c) 2004 Wiley Periodicals, Inc.
Flat-panel video resolution LED display system
NASA Astrophysics Data System (ADS)
Wareberg, P. G.; Kennedy, D. I.
The system consists of a 128 x 128 element X-Y addressable LED array fabricated from green-emitting gallium phosphide. The LED array is interfaced with a 128 x 128 matrix TV camera. Associated electronics provides for seven levels of grey scale above zero with a grey scale ratio of square root of 2. Picture elements are on 0.008 inch centers resulting in a resolution of 125 lines-per-inch and a display area of approximately 1 sq. in. The LED array concept lends itself to modular construction, permitting assembly of a flat panel screen of any desired size from 1 x 1 inch building blocks without loss of resolution. A wide range of prospective aerospace applications exist extending from helmet-mounted systems involving small dedicated arrays to multimode cockpit displays constructed as modular screens. High-resolution LED arrays are already used as CRT replacements in military film-marking reconnaissance applications.
Walters, Glenn D
2011-06-01
Recidivism was evaluated in 178 male inmates administered the Psychological Inventory of Criminal Thinking Styles (PICTS) and scored on the Level of Service Inventory-Revised: Screening Version (LSI-R:SV) 1-55 months before their release from prison. Age, prior charges, the LSI-R:SV total score, and the PICTS General Criminal Thinking (GCT), Proactive Criminal Thinking (P), and Reactive Criminal Thinking (R) scores served as predictors of recidivism in follow-ups spanning 1-53 months. Age, prior charges, and the PICTS GCT and R scales consistently and incrementally predicted general recidivism (all charges), whereas prior charges and the PICTS R scale consistently and incrementally predicted serious recidivism (more serious charges). Although these results support the predictive efficacy and incremental validity of content-relevant self-report measures of criminality like the PICTS, they also indicate that the effect is modest and in need of further clarification. One area requiring further investigation is the potential role of the PICTS, particularly the R scale, as a dynamic risk factor.
Schluter, Magdalen G; Hodgins, David C; Wolfe, Jody; Wild, T Cameron
2018-01-22
There is currently no well-validated measure that assesses a broad spectrum of substance-related and behavioural addictions in general populations. This study aimed to develop a brief self-attribution Screener for Substance and Behavioural Addictions (SSBA) to screen for four substances and six behaviours, and to compare its performance with established individual-behaviour screening instruments. A small, psychometrically optimal set of items to assess self-attributed indicators of addiction across alcohol, tobacco, cannabis, cocaine, gambling, shopping, videogaming, overeating, sexual activity and overworking were identified from a broader pool that was developed using a lay epidemiology qualitative approach. The suitability of the four-item single-factor solution was tested for each behaviour and scores were compared with those obtained from the sample using individual-behaviour screening instruments. Participants (n = 6000), broadly representative of the Canadian English-speaking adult population, were recruited through the Ipsos Reid Canadian Online Panel. Participants completed an item pool of 15 indicators of addiction for each target behaviour and a validation instrument for one randomly assigned behaviour. A set of four items identified using principal component and confirmatory factor analyses demonstrated good fit and excellent internal consistency (α = 0.87-0.95) across behaviours, and good convergent validity (rs = 0.44-0.8) with extant instruments measuring similar constructs, with only one exception (r = 0.26). The proposed Screener for Substance and Behavioural Addiction is a reliable and valid measure assessing the lay public's self-attributed indicators of addiction across 10 substances and behaviours. © 2018 Society for the Study of Addiction.
Smith, Jordan J; Morgan, Philip J; Plotnikoff, Ronald C; Dally, Kerry A; Salmon, Jo; Okely, Anthony D; Finn, Tara L; Babic, Mark J; Skinner, Geoff; Lubans, David R
2014-01-01
The negative consequences of unhealthy weight gain and the high likelihood of pediatric obesity tracking into adulthood highlight the importance of targeting youth who are 'at risk' of obesity. The aim of this paper is to report the rationale and study protocol for the 'Active Teen Leaders Avoiding Screen-time' (ATLAS) obesity prevention intervention for adolescent boys living in low-income communities. The ATLAS intervention will be evaluated using a cluster randomized controlled trial in 14 secondary schools in the state of New South Wales (NSW), Australia (2012 to 2014). ATLAS is an 8-month multi-component, school-based program informed by self-determination theory and social cognitive theory. The intervention consists of teacher professional development, enhanced school-sport sessions, researcher-led seminars, lunch-time physical activity mentoring sessions, pedometers for self-monitoring, provision of equipment to schools, parental newsletters, and a smartphone application and website. Assessments were conducted at baseline and will be completed again at 9- and 18-months from baseline. Primary outcomes are body mass index (BMI) and waist circumference. Secondary outcomes include BMI z-scores, body fat (bioelectrical impedance analysis), physical activity (accelerometers), muscular fitness (grip strength and push-ups), screen-time, sugar-sweetened beverage consumption, resistance training skill competency, daytime sleepiness, subjective well-being, physical self-perception, pathological video gaming, and aggression. Hypothesized mediators of behavior change will also be explored. ATLAS is an innovative school-based intervention designed to improve the health behaviors and related outcomes of adolescent males in low-income communities. Copyright © 2013 Elsevier Inc. All rights reserved.
Stalpers, Dewi; van der Linden, Dimitri; Kaljouw, Marian J; Schuurmans, Marieke J
2016-01-01
Deliberate screening allows detection of health risks that are otherwise not noticeable and allows expedient intervention to minimize complications and optimize outcomes, especially during critical events like hospitalization. Little research has evaluated the usefulness of screening performance and outcome indicators as measures to differentiate nursing quality, although policymakers are using them to benchmark hospitals. The aims of this study were to examine hospital performance based on nursing-sensitive screening indicators and to assess associations with hospital characteristics and nursing-sensitive outcomes for patients. A secondary use of nursing-sensitive data from the Dutch Health Care Inspectorate was performed, including the mandatory screening and outcome indicators related to delirium, malnutrition, pain and pressure ulcers. The sample consisted of all 93 hospitals in the Netherlands in 2011. High- and low-performing hospitals were determined based on the overall proportion of screened patients. Descriptive statistics and analysis of variance were used to examine screening performances in relation to hospital characteristics and nursing-sensitive outcomes. Over all hospitals, the average screening rates ranged from 59% (delirium) to 94% (pain). Organizational characteristics were not different in high- and low-performing hospitals. The hospitals with the best overall screening performances had significantly better results regarding protein intake within malnourished patients (p < .01). For mortality, marginal significant effects did not remain after controlling for organizational structures. No associations were found with prevalence of pressure ulcers and patient self-reported pain scores. The screening for patient risks is an important nursing task. Our findings suggest that nursing-sensitive screening indicators may be relevant measures for benchmarking nursing quality in hospitals. Time-trend studies are required to support our findings and to further investigate relations with nursing-sensitive outcomes.
Womack, James C; Mardirossian, Narbe; Head-Gordon, Martin; Skylaris, Chris-Kriton
2016-11-28
Accurate and computationally efficient exchange-correlation functionals are critical to the successful application of linear-scaling density functional theory (DFT). Local and semi-local functionals of the density are naturally compatible with linear-scaling approaches, having a general form which assumes the locality of electronic interactions and which can be efficiently evaluated by numerical quadrature. Presently, the most sophisticated and flexible semi-local functionals are members of the meta-generalized-gradient approximation (meta-GGA) family, and depend upon the kinetic energy density, τ, in addition to the charge density and its gradient. In order to extend the theoretical and computational advantages of τ-dependent meta-GGA functionals to large-scale DFT calculations on thousands of atoms, we have implemented support for τ-dependent meta-GGA functionals in the ONETEP program. In this paper we lay out the theoretical innovations necessary to implement τ-dependent meta-GGA functionals within ONETEP's linear-scaling formalism. We present expressions for the gradient of the τ-dependent exchange-correlation energy, necessary for direct energy minimization. We also derive the forms of the τ-dependent exchange-correlation potential and kinetic energy density in terms of the strictly localized, self-consistently optimized orbitals used by ONETEP. To validate the numerical accuracy of our self-consistent meta-GGA implementation, we performed calculations using the B97M-V and PKZB meta-GGAs on a variety of small molecules. Using only a minimal basis set of self-consistently optimized local orbitals, we obtain energies in excellent agreement with large basis set calculations performed using other codes. Finally, to establish the linear-scaling computational cost and applicability of our approach to large-scale calculations, we present the outcome of self-consistent meta-GGA calculations on amyloid fibrils of increasing size, up to tens of thousands of atoms.
NASA Astrophysics Data System (ADS)
Womack, James C.; Mardirossian, Narbe; Head-Gordon, Martin; Skylaris, Chris-Kriton
2016-11-01
Accurate and computationally efficient exchange-correlation functionals are critical to the successful application of linear-scaling density functional theory (DFT). Local and semi-local functionals of the density are naturally compatible with linear-scaling approaches, having a general form which assumes the locality of electronic interactions and which can be efficiently evaluated by numerical quadrature. Presently, the most sophisticated and flexible semi-local functionals are members of the meta-generalized-gradient approximation (meta-GGA) family, and depend upon the kinetic energy density, τ, in addition to the charge density and its gradient. In order to extend the theoretical and computational advantages of τ-dependent meta-GGA functionals to large-scale DFT calculations on thousands of atoms, we have implemented support for τ-dependent meta-GGA functionals in the ONETEP program. In this paper we lay out the theoretical innovations necessary to implement τ-dependent meta-GGA functionals within ONETEP's linear-scaling formalism. We present expressions for the gradient of the τ-dependent exchange-correlation energy, necessary for direct energy minimization. We also derive the forms of the τ-dependent exchange-correlation potential and kinetic energy density in terms of the strictly localized, self-consistently optimized orbitals used by ONETEP. To validate the numerical accuracy of our self-consistent meta-GGA implementation, we performed calculations using the B97M-V and PKZB meta-GGAs on a variety of small molecules. Using only a minimal basis set of self-consistently optimized local orbitals, we obtain energies in excellent agreement with large basis set calculations performed using other codes. Finally, to establish the linear-scaling computational cost and applicability of our approach to large-scale calculations, we present the outcome of self-consistent meta-GGA calculations on amyloid fibrils of increasing size, up to tens of thousands of atoms.
Production and characterization of tearless and non-pungent onion
Kato, Masahiro; Masamura, Noriya; Shono, Jinji; Okamoto, Daisaku; Abe, Tomoko; Imai, Shinsuke
2016-01-01
The onion lachrymatory factor (LF) is produced from trans-S-1-propenyl-L-cysteine sulfoxide (PRENCSO) through successive reactions catalyzed by alliinase (EC 4.4.1.4) and lachrymatory factor synthase (LFS), and is responsible for the tear inducing-property and the pungency of fresh onions. We developed tearless, non-pungent onions non-transgenically by irradiating seeds with neon-ion at 20 Gy. The bulbs obtained from the irradiated seeds and their offspring bulbs produced by selfing were screened by organoleptic assessment of tear-inducing property or HPLC analysis of LF production. After repeated screening and seed production by selfing, two tearless, non-pungent bulbs were identified in the third generation (M3) bulbs. Twenty M4 bulbs obtained from each of them showed no tear-inducing property or pungency when evaluated by 20 sensory panelists. The LF production levels in these bulbs were approximately 7.5-fold lower than those of the normal onion. The low LF production levels were due to reduction in alliinase activity, which was a result of low alliinase mRNA expression (less than 1% of that in the normal onion) and consequent low amounts of the alliinase protein. These tearless, non-pungent onions should be welcomed by all who tear while chopping onions and those who work in facilities where fresh onions are processed. PMID:27048847
Sultana, Farhana; Mullins, Robyn; Murphy, Michael; English, Dallas R; Simpson, Julie A; Drennan, Kelly T; Heley, Stella; Wrede, C David; Brotherton, Julia M L; Saville, Marion; Gertig, Dorota M
2015-08-01
Background The study evaluated acceptability, invitation letters and the test kit for a trial of human papillomavirus (HPV) self-sampling among never- and under-screened women in Australia. Victorian women, 30-69 years, who had never had a Pap test or were overdue for one, participated. Four focus groups including eight to nine participants segmented by age (30-49 and 50-69 years) and screening history (never- and under-screened) were conducted in August 2013. Discussions were recorded and transcribed verbatim and data analysed using thematic content analysis. The response to the concept of HPV self-sampling was positive. Decision-making was largely influenced by the content of a pre-invitation letter. Appealing features of self-sampling were cost (free), convenience (home-based) and anticipated less discomfort (with a swab) than a Pap test. Small kits that fit in mailboxes were preferred over post office parcel collection. The perceived barriers include concerns about test accuracy and lack of confidence that a home-based test would give the same results as a physician administered test. Women wanted information on the timing of receipt of the results and information about the organisation providing the test. HPV self-sampling is a possible alternative for Australian women who are reluctant to have a Pap test and may increase the likelihood of participation in cervical cancer screening if women's concerns about it can be addressed. The findings of this study are relevant for researchers, policymakers and practitioners implementing self-sampling for under-screened women as part of cervical screening programs.
Kim, Yi-Soon; Kim, Min-Za; Jeong, Ihn-Sook
2004-08-01
This study was aimed to identify the effect of self-foot reflexology on the relief of premenstrual syndrome and dysmenorrhea in high school girls. Study subjects was 236 women residing in the community, teachers and nurses who were older than 45 were recruited. Data was collected with self administered questionnaires from July 1st to August 31st, 2003 and analysed using SPSS/WIN 10.0 with Xtest, t-test, and stepwise multiple logistic regression at a significant level of =.05. The breast cancer screening rate was 57.2%, and repeat screening rate was 15.3%. With the multiple logistic regression analysis, factors associated with mammography screening were age and perceived barriers of action, and factors related to the repeat mammography screening were education level and other cancer screening experience. Based on the results, we recommend the development of an intervention program to decrease the perceived barrier of action, to regard mammography as an essential test in regular check-up, and to give active advertisement and education to the public to improve the rates of breast cancer screening and repeat screening.
NASA Astrophysics Data System (ADS)
Fujiwara, Takeo; Nishino, Shinya; Yamamoto, Susumu; Suzuki, Takashi; Ikeda, Minoru; Ohtani, Yasuaki
2018-06-01
A novel tight-binding method is developed, based on the extended Hückel approximation and charge self-consistency, with referring the band structure and the total energy of the local density approximation of the density functional theory. The parameters are so adjusted by computer that the result reproduces the band structure and the total energy, and the algorithm for determining parameters is established. The set of determined parameters is applicable to a variety of crystalline compounds and change of lattice constants, and, in other words, it is transferable. Examples are demonstrated for Si crystals of several crystalline structures varying lattice constants. Since the set of parameters is transferable, the present tight-binding method may be applicable also to molecular dynamics simulations of large-scale systems and long-time dynamical processes.
McCormack, Gavin R; Mardinger, Cynthia
2015-01-01
Objectives Despite evidence for an association between the built environment and physical activity, less evidence exists regarding relations between the built environment and sedentary behaviour. This study investigated the extent to which objectively assessed and self-reported neighbourhood walkability, in addition to individual-level characteristics, were associated with leisure-based screen time in adults. We hypothesised that leisure-based screen time would be lower among adults residing in objectively assessed and self-reported ‘high walkable’ versus ‘low walkable’ neighbourhoods. Setting The study was undertaken in Calgary, Alberta, Canada in 2007/2008. Participants A random cross-section of adults who provided complete telephone interview and postal survey data (n=1906) was included. Captured information included leisure-based screen time, moderate-intensity and vigorous-intensity physical activity, perceived neighbourhood walkability, sociodemographic characteristics, self-reported health status, and self-reported height and weight. Based on objectively assessed built characteristics, participant's neighbourhoods were identified as being low, medium or high walkable. Primary and secondary outcome measures Using multiple linear regression, hours of leisure-based screen time per day was regressed on self-reported and objectively assessed walkability adjusting for sociodemographic and health-related covariates. Results Compared to others, residing in an objectively assessed high walkable neighbourhood, women, having a college education, at least one child at home, a household income ≥$120 000/year, and a registered motor vehicle at home, reporting very good-to-excellent health and healthy weight, and achieving 60 min/week of vigorous-intensity physical activity were associated (p<0.05) with less leisure-based screen time. Marital status, dog ownership, season, self-reported walkability and achieving 210 min of moderate-intensity physical activity were not significantly associated with leisure-based screen time. Conclusions Improving neighbourhood walkability could decrease leisure-based television and computer screen time. Programmes aimed at reducing sedentary behaviour may want to consider an individual's sociodemographic characteristics, physical activity level, health status and weight status, in addition to the walkability of their neighbourhood as these factors were found to be important independent correlates of leisure-based screen time. PMID:26608640
Numerical Simulations of Dynamical Mass Transfer in Binaries
NASA Astrophysics Data System (ADS)
Motl, P. M.; Frank, J.; Tohline, J. E.
1999-05-01
We will present results from our ongoing research project to simulate dynamically unstable mass transfer in near contact binaries with mass ratios different from one. We employ a fully three-dimensional self-consistent field technique to generate synchronously rotating polytropic binaries. With our self-consistent field code we can create equilibrium binaries where one component is, by radius, within about 99 of filling its Roche lobe for example. These initial configurations are evolved using a three-dimensional, Eulerian hydrodynamics code. We make no assumptions about the symmetry of the subsequent flow and the entire binary system is evolved self-consistently under the influence of its own gravitational potential. For a given mass ratio and polytropic index for the binary components, mass transfer via Roche lobe overflow can be predicted to be stable or unstable through simple theoretical arguments. The validity of the approximations made in the stability calculations are tested against our numerical simulations. We acknowledge support from the U.S. National Science Foundation through grants AST-9720771, AST-9528424, and DGE-9355007. This research has been supported, in part, by grants of high-performance computing time on NPACI facilities at the San Diego Supercomputer Center, the Texas Advanced Computing Center and through the PET program of the NAVOCEANO DoD Major Shared Resource Center in Stennis, MS.
Ring current Atmosphere interactions Model with Self-Consistent Magnetic field
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jordanova, Vania; Jeffery, Christopher; Welling, Daniel
The Ring current Atmosphere interactions Model with Self-Consistent magnetic field (B) is a unique code that combines a kinetic model of ring current plasma with a three dimensional force-balanced model of the terrestrial magnetic field. The kinetic portion, RAM, solves the kinetic equation to yield the bounce-averaged distribution function as a function of azimuth, radial distance, energy and pitch angle for three ion species (H+, He+, and O+) and, optionally, electrons. The domain is a circle in the Solar-Magnetic (SM) equatorial plane with a radial span of 2 to 6.5 RE. It has an energy range of approximately 100 eVmore » to 500 KeV. The 3-D force balanced magnetic field model, SCB, balances the JxB force with the divergence of the general pressure tensor to calculate the magnetic field configuration within its domain. The domain ranges from near the Earth’s surface, where the field is assumed dipolar, to the shell created by field lines passing through the SM equatorial plane at a radial distance of 6.5 RE. The two codes work in tandem, with RAM providing anisotropic pressure to SCB and SCB returning the self-consistent magnetic field through which RAM plasma is advected.« less
Recollections of Childhood Religious Identity and Behavior as a Function of Adult Religiousness
Hayward, R. David; Maselko, Joanna; Meador, Keith G.
2012-01-01
People have a strong motivation to maintain a self-concept that is coherent and consistent over time. Religion is an central source of social identity for many people, but its importance is prone to dramatic change across the life course. To maintain a consistent perception of self, recollections of one’s own past religiousness may shift to better fit with the present. This study examined changes between early and middle adulthood in retrospective perceptions of religious behavior and identity in childhood. Data from a population-based birth cohort sample were matched with data from individuals who participated in at least two of three adult follow-up studies, at intervals of approximately 10 years. Logistic regression was used to analyze the association of final recollections of childhood behavior and identity with previous recollections and current religious characteristics. Consistent with the predictions of temporal self-appraisal theory, participants’ perception of their religious identity as children tended to change over time to match their adult religious identity. Recollections of childhood religious behavior were more stable than recollections of religious identity, and change was unrelated to adult behavior. These results have implications for studying religious characteristics using retrospective measures, regarding their accuracy and their independence from contemporary measures. PMID:22844186
Fletcher, E; Leech, R; McNaughton, S A; Dunstan, D W; Lacy, K E; Salmon, J
2015-09-01
Screen time, but not overall sedentary behaviour, is consistently related to cardiometabolic health in adolescents. Because of the associations screen time has with dietary intake, diet may be an important factor in the screen time and health relationship; however, evidence has not previously been synthesized. Thus, the aim of this systematic review was to explore whether the associations between various sedentary behaviours and cardiometabolic risk markers are independent of dietary intake in adolescents. Online databases and personal libraries were searched for peer-reviewed original research articles published in English before March 2014. Included studies assessed associations between sedentary behaviour and cardiometabolic markers in 12- to 18-year-olds and adjusted for dietary intake. Twenty-five studies met the inclusion criteria. From the 21 studies examining sedentary behaviour and adiposity, the majority found significant positive associations between television viewing, screen time and self-reported overall sedentary behaviour with markers of adiposity, independent of dietary intake. No significant associations between screen time with blood pressure and cholesterol were reported. Sedentary behaviour appears to be associated with adiposity in adolescents, irrespective of dietary intake. However, the variability of dietary variables between studies suggests further work is needed to understand the role of dietary intake when examining these associations in youth. © 2015 World Obesity.
Education, Consent, and Counseling in Sickle Cell Screening Programs: Report of a Survey.
ERIC Educational Resources Information Center
Farfel, Mark R.; Holtzman, Neil A.
1984-01-01
A 1980 survey of sickle cell screening facilities in Maryland, found that approximately 52,000 persons were screened, 13,000 without informed consent. Many facilities also failed to provide education and counseling. Units dedicated entirely to screening were most compliant with State regulations. (Author/CJM)
Khosropour, Christine M; Broad, Jennifer M; Scholes, Delia; Saint-Johnson, Jacquelyn; Manhart, Lisa E; Golden, Matthew R
2014-11-01
Population-based surveys (self-report) and health insurance administrative data (Healthcare Effectiveness Data and Information Set [HEDIS]) are used to estimate chlamydia screening coverage in the United States. Estimates from these methods differ, but few studies have compared these 2 indices in the same population. In 2010, we surveyed a random sample of women aged 18 to 25 years enrolled in a Washington State-managed care organization. Respondents were asked if they were sexually active in last year and if they tested for chlamydia in that time. We linked survey responses to administrative records of chlamydia testing and reproductive/testing services used, which comprise the HEDIS definition of the screened population and the sexually active population, respectively. We compared self-report and HEDIS using 3 outcomes: (1) sexual activity (gold standard = self-report), (2) any chlamydia screening (no gold standard), and (3) within-plan chlamydia screening (gold standard = HEDIS). Of 954 eligible respondents, 377 (40%) completed the survey and consented to administrative record linkage. Chlamydia screening estimates for HEDIS and self-report were 47% and 53%, respectively. The sensitivity and specificity of HEDIS to define sexually active women were 84.8% (95% confidence interval [CI], 79.6%-89.1%) and 63.5% (95% CI, 52.4%-73.7%), respectively. Forty percent of women had a chlamydia test in their administrative record, but 53% self-reported being tested for chlamydia (κ = 0.35); 19% reported out-of-plan chlamydia testing. The sensitivity of self-reported within-plan chlamydia testing was 71.3% (95% CI, 61.0%-80.1%); the specificity was 80.6% (95% CI, 72.6%-87.2%). The Healthcare Effectiveness Data and Information Set does not accurately identify sexually active women and may underestimate chlamydia testing coverage. Self-reported testing may not be an accurate measure of true chlamydial testing coverage.
NASA Technical Reports Server (NTRS)
Lamar, John E.; Brandon, Jay; Stacy, Kathryn; Johnson, Thomas D., Jr.; Severance, Kurt; Childers, Brooks A.
1993-01-01
A flight research program to study the flow structure and separated-flow origins over an F-106B aircraft wing is described. The flight parameters presented include Mach numbers from 0.26 to 0.81, angles of attack from 8.5 deg to 22.5 deg, Reynolds numbers from 22.6 x 10(exp 6) to 57.3 x 10(exp 6) and load factors from 0.9 to 3.9 times the acceleration due to gravity. Techniques for vapor screens, image enhancement, photogrammetry, and computer graphics are integrated to analyze vortex-flow systems. Emphasis is placed on the development and application of the techniques. The spatial location of vortex cores and their tracks over the wing are derived from the analysis. Multiple vortices are observed and are likely attributed to small surface distortions in the wing leading-edge region. A major thrust is to correlate locations of reattachment lines obtained from the off-surface (vapor-screen) observations with those obtained from on-surface oil-flow patterns and pressure-port data. Applying vapor-screen image data to approximate reattachment lines is experimental, but depending on the angle of attack, the agreement with oil-flow results is generally good. Although surface pressure-port data are limited, the vapor-screen data indicate reattachment point occurrences consistent with the available data.
NASA Astrophysics Data System (ADS)
Welden, Alicia Rae; Rusakov, Alexander A.; Zgid, Dominika
2016-11-01
Including finite-temperature effects from the electronic degrees of freedom in electronic structure calculations of semiconductors and metals is desired; however, in practice it remains exceedingly difficult when using zero-temperature methods, since these methods require an explicit evaluation of multiple excited states in order to account for any finite-temperature effects. Using a Matsubara Green's function formalism remains a viable alternative, since in this formalism it is easier to include thermal effects and to connect the dynamic quantities such as the self-energy with static thermodynamic quantities such as the Helmholtz energy, entropy, and internal energy. However, despite the promising properties of this formalism, little is known about the multiple solutions of the non-linear equations present in the self-consistent Matsubara formalism and only a few cases involving a full Coulomb Hamiltonian were investigated in the past. Here, to shed some light onto the iterative nature of the Green's function solutions, we self-consistently evaluate the thermodynamic quantities for a one-dimensional (1D) hydrogen solid at various interatomic separations and temperatures using the self-energy approximated to second-order (GF2). At many points in the phase diagram of this system, multiple phases such as a metal and an insulator exist, and we are able to determine the most stable phase from the analysis of Helmholtz energies. Additionally, we show the evolution of the spectrum of 1D boron nitride to demonstrate that GF2 is capable of qualitatively describing the temperature effects influencing the size of the band gap.
Screening for anxiety disorders in patients with coronary artery disease.
Bunevicius, Adomas; Staniute, Margarita; Brozaitiene, Julija; Pop, Victor J M; Neverauskas, Julius; Bunevicius, Robertas
2013-03-11
Anxiety disorders are prevalent and associated with poor prognosis in patients with coronary artery disease (CAD). However, studies examining screening of anxiety disorders in CAD patients are lacking. In the present study we evaluated the prevalence of anxiety disorders in patients with CAD and diagnostic utility of self-rating scales for screening of anxiety disorders. Five-hundred and twenty-three CAD patients not receiving psychotropic treatments at initiation of rehabilitation program completed self-rating scales (Hospital Anxiety and Depression Scale or HADS; Spielberger State-Anxiety Inventory or SSAI; and Spielberger Trait-Anxiety Inventory or STAI) and were interviewed for generalized anxiety disorder (GAD), social phobia, panic disorder and agoraphobia (Mini-International Neuropsychiatric Interview or MINI). Thirty-eight (7%) patients were diagnosed with anxiety disorder(s), including GAD (5%), social phobia (2%), agoraphobia (1%) and panic disorder (1%). Areas under the ROC curve of the HADS Anxiety subscale (HADS-A), STAI and SSAI for screening of any anxiety disorder were .81, .80 and .72, respectively. Optimal cut-off values for screening of any anxiety disorders were ≥ 8 for the HADS-A (sensitivity = 82%; specificity = 76%; and positive predictive value (PPV) = 21%); ≥ 45 for the STAI (sensitivity = 89%; specificity = 56%; and PPV = 14%); and ≥ 40 for the SSAI (sensitivity = 84%; specificity = 55%; PPV = 13%). In a subgroup of patients (n = 340) scoring below the optimal major depressive disorder screening cut-off value of HADS-Depression subscale (score <5), the HADS-A, STAI and SSAI had moderate-high sensitivity (range from 69% to 89%) and low PPVs (≤ 22%) for GAD and any anxiety disorders. Anxiety disorders are prevalent in CAD patients but can be reliably identified using self-rating scales. Anxiety self-rating scales had comparable sensitivities but the HADS-A had greater specificity and PPV when compared to the STAI and SSAI for screening of anxiety disorders. However, false positive rates were high, suggesting that patients with positive screening results should undergo psychiatric interview prior to initiating treatment for anxiety disorders and that routine use of anxiety self-rating scales for screening purposes can increase healthcare costs. Anxiety screening has incremental value to depression screening for identifying anxiety disorders.
Wisner, Katherine L.; Sit, Dorothy K. Y.; McShea, Mary C.; Rizzo, David M.; Zoretich, Rebecca A.; Hughes, Carolyn L.; Eng, Heather F.; Luther, James F.; Wisniewski, Stephen R.; Costantino, Michelle L.; Confer, Andrea L.; Moses-Kolko, Eyclie L.; Famy, Christopher S.; Hanusa, Barbara H.
2015-01-01
Importance The period prevalence of depression among women is 21.9% during the first postpartum year; however, questions remain about the value of screening for depression. Objectives To screen for depression in postpartum women and evaluate positive screen findings to determine the timing of episode onset, rate and intensity of self-harm ideation, and primary and secondary DSM-IV disorders to inform treatment and policy decisions. Design Sequential case series of women who recently gave birth. Setting Urban academic women’s hospital. Participants During the maternity hospitalization, women were offered screening at 4 to 6 weeks post parturn by telephone. Screen-positive women were invited to undergo psychiatric evaluations in their homes. Main Outcomes and Measures A positive screen finding was an Edinburgh Postnatal Depression Scale (EPDS) score of 10 or higher. Self-harm ideation was assessed on EPDS item 10: “The thought of harming myself has occurred to me” (yes, quite often; sometimes; hardly ever; never). Screen-positive women underwent evaluation with the Structured Clinical Interview for DSM-IV for Axis I primary and secondary diagnoses. Results Ten thousand mothers underwent screening, with positive findings in 1396 (14.0%); of these, 826 (59.2%) completed the home visits and 147 (10.5%) completed a telephone diagnostic interview. Screen-positive women were more likely to be younger, African American, publicly insured, single, and less well educated. More episodes began post partum (40.1%), followed by during pregnancy (33.4%) and before pregnancy (26.5%). In this population, 19.3% had self-harm ideation. All mothers with the highest intensity of self-harm ideation were identified with the EPDS score of 10 or higher. The most common primary diagnoses were unipolar depressive disorders (68.5%), and almost two-thirds had co-morbid anxiety disorders. A striking 22.6% had bipolar disorders. Conclusions and Relevance The most common diagnosis in screen-positive women was major depressive disorder with comorbid generalized anxiety disorder. Strategies to differentiate women with bipolar from unipolar disorders are needed. Trial Registration clinicaltrials.gov Identifier: NCT00282776 PMID:23487258
Zhang, Xindi; Warren, Jim; Corter, Arden; Goodyear-Smith, Felicity
2016-01-01
This paper describes development of a prototype data analytics portal for analysis of accumulated screening results from eCHAT (electronic Case-finding and Help Assessment Tool). eCHAT allows individuals to conduct a self-administered lifestyle and mental health screening assessment, with usage to date chiefly in the context of primary care waiting rooms. The intention is for wide roll-out to primary care clinics, including secondary school based clinics, resulting in the accumulation of population-level data. Data from a field trial of eCHAT with sexual health questions tailored to youth were used to support design of a data analytics portal for population-level data. The design process included user personas and scenarios, screen prototyping and a simulator for generating large-scale data sets. The prototype demonstrates the promise of wide-scale self-administered screening data to support a range of users including practice managers, clinical directors and health policy analysts.
Density-dependent covariant energy density functionals
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lalazissis, G. A.
2012-10-20
Relativistic nuclear energy density functionals are applied to the description of a variety of nuclear structure phenomena at and away fromstability line. Isoscalar monopole, isovector dipole and isoscalar quadrupole giant resonances are calculated using fully self-consistent relativistic quasiparticle randomphase approximation, based on the relativistic Hartree-Bogoliubovmodel. The impact of pairing correlations on the fission barriers in heavy and superheavy nuclei is examined. The role of pion in constructing desnity functionals is also investigated.
Chronic substance use and self-harm in a primary health care setting.
Breet, Elsie; Bantjes, Jason; Lewis, Ian
2018-06-19
Chronic substance use (CSU) is associated with health problems, including selfharm, placing a significant burden on health care resources and emergency departments (EDs). This is problematic in low- and middle-income countries like South Africa (SA), where primary care facilitates and emergency departments (EDs) are often poorly resourced. To investigate the epidemiology of CSU and self-harm and to consider the implications for primary health care service delivery and suicide prevention in SA. Data were collected from 238 consecutive self-harm patients treated at the emergency department (ED) of an urban hospital in SA. The data were analysed using bivariate and multivariate analyses. Approximately 37% of self-harm patients reported CSU. The patients in the CSU subgroup, compared to other self-harm patients, were more likely to be men (odds ratio[OR] = 8.33, 95% confidence interval [CI] = 3.19-20.9, p < 0.001), to have self-harmed by inflicting damage to their body tissue OR = 4.45, 95% CI = 1.77-11.2, p < 0.01) and to have a history of self-harm (OR = 3.71, 95% CI = 1.44-9.54, p = 0.007). A significantly smaller proportion of CSU patients, compared to other self-harm patients, were referred for psychiatric assessment (OR = 8.05, 95% CI = 4.16-15.7, p < 0.001). The findings of this study confirm that CSU is associated with greater service utilisation and repetition of self-harm among patients in primary health care settings. Treating self-harm as the presenting problem within primary care settings does not necessarily ensure that patients receive the care that they need. It might be helpful to include psychiatric assessments and screening for CSU as an integral component of care for self-harm patientswho present in primary health care settings.
Lindblom, Katrina; Gregory, Tess; Flight, Ingrid H K; Zajac, Ian
2011-01-01
Objective This study investigated the efficacy of an internet-based personalized decision support (PDS) tool designed to aid in the decision to screen for colorectal cancer (CRC) using a fecal occult blood test. We tested whether the efficacy of the tool in influencing attitudes to screening was mediated by perceived usability and acceptability, and considered the role of computer self-efficacy and computer anxiety in these relationships. Methods Eighty-one participants aged 50–76 years worked through the on-line PDS tool and completed questionnaires on computer self-efficacy, computer anxiety, attitudes to and beliefs about CRC screening before and after exposure to the PDS, and perceived usability and acceptability of the tool. Results Repeated measures ANOVA found that PDS exposure led to a significant increase in knowledge about CRC and screening, and more positive attitudes to CRC screening as measured by factors from the Preventive Health Model. Perceived usability and acceptability of the PDS mediated changes in attitudes toward CRC screening (but not CRC knowledge), and computer self-efficacy and computer anxiety were significant predictors of individuals' perceptions of the tool. Conclusion Interventions designed to decrease computer anxiety, such as computer courses and internet training, may improve the acceptability of new health information technologies including internet-based decision support tools, increasing their impact on behavior change. PMID:21857024
Susceptibility of a Magnetic Impurity in Weakly Localized Regime
NASA Astrophysics Data System (ADS)
Suga, Seiichiro; Kasai, Hideaki; Okiji, Ayao
1987-12-01
Interplay between the randomness and the s-d exchange interaction is investigated theoretically in the weakly localized regime through the temperature dependence of the susceptibility. In the first half the analytic calculations are performed perturbatively in terms of the s-d exchange coupling constant. It is shown that the quantum corrections to the susceptibility construct geometric series and can be summed up as simple formulae within the framework of the most divergent approximation. In the second half the numerical calculations are performed with the use of the self-consistent ladder approximation. It is shown that the effective Curie constant decreases more rapidly with decreasing the temperature than that in the usual Kondo systems.
Roughness of stylolites: implications of 3D high resolution topography measurements.
Schmittbuhl, J; Renard, F; Gratier, J P; Toussaint, R
2004-12-03
Stylolites are natural pressure-dissolution surfaces in sedimentary rocks. We present 3D high resolution measurements at laboratory scales of their complex roughness. The topography is shown to be described by a self-affine scaling invariance. At large scales, the Hurst exponent is zeta(1) approximately 0.5 and very different from that at small scales where zeta(2) approximately 1.2. A crossover length scale at around L(c)=1 mm is well characterized. Measurements are consistent with a Langevin equation that describes the growth of a stylolitic interface as a competition between stabilizing long range elastic interactions at large scales or local surface tension effects at small scales and a destabilizing quenched material disorder.
Wachira, J; Busakhala, A; Chite, F; Naanyu, V; Kisuya, J; Otieno, G; Keter, A; Mwangi, A; Inui, T
2017-02-03
Our study objective was to determine the validity and reliability of the breast module of a cancer awareness measure (BCAM) among adult women in western Kenya. The study was conducted between October and November 2012, following three breast cancer screening events. Purposive and systematic random sampling methods were used to identity 48 women for cognitive focus group discussions, and 1061 (594 who attended vs. 467 who did not attend screening events) for surveys, respectively. Face and psychometric validity of the BCAM survey was assessed using cognitive testing, factor analysis of survey data, and correlations. Internal reliability was assessed using Cronbach's alpha. Among survey participants, the overall median age was 34 (IQR: 26-44) years. Compared to those women who did not attend the screening events, women attendees were older (median: 35 vs. 32 years, p = 0.001) more often married (79% vs. 72%, p = 0.006), more educated (52% vs. 46% with more than an elementary level of education, p = 0.001), more unemployed (59% vs. 11%, p = 0.001), more likely to report doing breast self-examination (56% vs. 40%, p = 0.001) and more likely to report having felt a breast lump (16% vs. 7%, p = 0.001). For domain 1 on knowledge of breast cancer symptoms, one factor (three items) with Eigen value of 1.76 emerged for the group that did not attend screening, and 1.50 for the group that attended screening. For both groups two factors (factor 1 "internal influences" and factor 2 "external influences") emerged among domain 4 on barriers to screening, with varied item loadings and Eigen values. There were no statistically significant differences in the factor scores between attendees and non-attendees. There were significant associations between factor scores and other attributes of the surveyed population, including associations with occupation, transportation type, and training for and practice of breast self-examination. Cronbach's alpha showed an acceptable internal consistency. Certain subpopulations are less likely than others to attend breast screening in Kenya. A survey measure of breast cancer knowledge and perceived barriers to screening shows promise for use in Kenya for characterizing clinical and community population beliefs, but needs adaptation for setting, language and culture.
Strategy for Identifying Repurposed Drugs for the Treatment of Cerebral Cavernous Malformation
Gibson, Christopher C.; Zhu, Weiquan; Davis, Chadwick T.; Bowman-Kirigin, Jay A.; Chan, Aubrey C.; Ling, Jing; Walker, Ashley E.; Goitre, Luca; Monache, Simona Delle; Retta, Saverio Francesco; Shiu, Yan-Ting E.; Grossmann, Allie H.; Thomas, Kirk R.; Donato, Anthony J.; Lesniewski, Lisa A.; Whitehead, Kevin J.; Li, Dean Y.
2014-01-01
Background Cerebral cavernous malformation (CCM) is a hemorrhagic stroke disease affecting up to 0.5% of North Americans with no approved non-surgical treatment. A subset of patients have a hereditary form of the disease due primarily to loss-of-function mutations in KRIT1, CCM2, or PDCD10. We sought to identify known drugs that could be repurposed to treat CCM. Methods and Results We developed an unbiased screening platform based on both cellular and animal models of loss-of-function of CCM2. Our discovery strategy consisted of four steps: an automated immunofluorescence and machine-learning-based primary screen of structural phenotypes in human endothelial cells deficient in CCM2; a secondary screen of functional changes in endothelial stability in these same cells; a rapid in vivo tertiary screen of dermal microvascular leak in mice lacking endothelial Ccm2; and finally a quaternary screen of CCM lesion burden in these same mice. We screened 2,100 known drugs and bioactive compounds, and identified two candidates for further study, cholecalciferol (Vitamin D3) and tempol (a scavenger of superoxide). Each drug decreased lesion burden in a mouse model of CCM vascular disease by approximately 50%. Conclusions By identifying known drugs as potential therapeutics for CCM, we have decreased the time, cost, and risk of bringing treatments to patients. Each drug also prompts additional exploration of biomarkers of CCM disease. We further suggest that the structure-function screening platform presented here may be adapted and scaled to facilitate drug discovery for diverse loss-of-function genetic vascular disease. PMID:25486933
Garrett, Jenna J; Barrington, Clare
2013-01-01
Cervical cancer is the leading cause of cancer death for women in Honduras, and sexual behaviour and low screening uptake are two major factors contributing to high rates of morbidity and mortality. A qualitative study was conducted to investigate barriers that prevent rural Honduran women from engaging in screening and ways that women overcome those barriers. This study examined examples of positive deviance, or individuals engaging in the uncommon but beneficial practise of screening. Amor por sí misma (self-love), and social support were identified as two constructs women employed to overcome barriers to screening. Participants defined self-love as the act of displaying care and concern for oneself and one's health and suggested that it compels women to participate in screening. Social support was defined as receiving tangible aid and advice from others that facilitated women's screening participation. Findings suggest that the concept of self-love could be used in future screening promotion efforts and that integrating social support would also be beneficial. Engaging men in sexual and reproductive health programming is suggested in order to ensure male partners offer social support for screening and to challenge the cultural, gender and sexual norms that place women at higher risk for cervical cancer.
Design and results of a culturally tailored cancer outreach project by and for Micronesian women.
Aitaoto, Nia; Braun, Kathryn L; Estrella, Julia; Epeluk, Aritae; Tsark, JoAnn
2012-01-01
In 2005, approximately 26% of Micronesian women aged 40 or older in Hawai'i used mammography for breast cancer screening. We describe an 18-month project to increase screening participation in this population by tailoring educational materials and using a lay educator approach. New immigrants to Hawai'i are Marshallese from the Republic of the Marshall Islands and Chuukese, Pohnpeians, and Kosraeans from the Federated States of Micronesia. In Hawai'i, these 4 groups refer to themselves collectively as Micronesians, although each group has its own distinct culture and language. From 2006 through 2007, we applied principles of community-based participatory research--trust building, joint assessment, cultural tailoring of materials, and skills transfer--to develop and track the reach of Micronesian women lay educators in implementing a cancer awareness program among Micronesian women living in Hawai'i. Using our tailored in-language materials, 11 lay educators (5 Chuukese, 3 Marshallese, 2 Pohnpeians, and 1 Kosraean) provided one-on-one and small group in-language cancer information sessions to 567 Micronesian women (aged 18-75 years). Among the 202 women aged 40 or older eligible for mammography screening, 166 (82%) had never had a mammogram and were assisted to screening appointments. After 6 months, 146 (88%) of the 166 had received a mammogram, increasing compliance from 18% to 90%. Lay educators reported increases in their skills and their self-esteem and want to extend their skills to other health issues, including diabetes management and immunization. Tailoring materials and using the lay educator model successfully increased participation in breast cancer screening. This model may work in other communities that aim to reduce disparities in access to cancer screening.
Sequence-based screening for self-sufficient P450 monooxygenase from a metagenome library.
Kim, B S; Kim, S Y; Park, J; Park, W; Hwang, K Y; Yoon, Y J; Oh, W K; Kim, B Y; Ahn, J S
2007-05-01
Cytochrome P450 monooxygenases (CYPs) are useful catalysts for oxidation reactions. Self-sufficient CYPs harbour a reductive domain covalently connected to a P450 domain and are known for their robust catalytic activity with great potential as biocatalysts. In an effort to expand genetic sources of self-sufficient CYPs, we devised a sequence-based screening system to identify them in a soil metagenome. We constructed a soil metagenome library and performed sequence-based screening for self-sufficient CYP genes. A new CYP gene, syk181, was identified from the metagenome library. Phylogenetic analysis revealed that SYK181 formed a distinct phylogenic line with 46% amino-acid-sequence identity to CYP102A1 which has been extensively studied as a fatty acid hydroxylase. The heterologously expressed SYK181 showed significant hydroxylase activity towards naphthalene and phenanthrene as well as towards fatty acids. Sequence-based screening of metagenome libraries is expected to be a useful approach for searching self-sufficient CYP genes. The translated product of syk181 shows self-sufficient hydroxylase activity towards fatty acids and aromatic compounds. SYK181 is the first self-sufficient CYP obtained directly from a metagenome library. The genetic and biochemical information on SYK181 are expected to be helpful for engineering self-sufficient CYPs with broader catalytic activities towards various substrates, which would be useful for bioconversion of natural products and biodegradation of organic chemicals.
Barbee, Lindley A; Tat, Susana; Dhanireddy, Shireesha; Marrazzo, Jeanne M
2016-06-01
Rates of screening for bacterial sexually transmitted infections (STI) among men who have sex with men in HIV care settings remain low despite high prevalence of these infections. STI self-testing may help increase screening rates in clinical settings. We implemented an STI self-testing program at a large, urban HIV care clinic and evaluated its effectiveness and acceptability. We compared measures obtained during the first year of the STI self-testing program (Intervention Year, April 1, 2013-March 31, 2014) to Baseline Year (January 1, 2012-December 31, 2012) to determine: (1) overall clinic change in STI testing coverage and diagnostic yield and; (2) program-specific outcomes including appropriate anatomic site screening and patient-reported acceptability. Overall, testing for gonorrhea and chlamydia increased significantly between Baseline and Intervention Year, and 50% more gonococcal and 47% more chlamydial infections were detected. Syphilis testing coverage remained unchanged. Nearly 95% of 350 men who participated in the STI self-testing program completed site-specific testing appropriately based on self-reported exposures, and 92% rated their self-testing experience as "good" or "very good." STI self-testing in HIV care settings significantly increases testing coverage and detection of gonorrhea and chlamydia, and the program is acceptable to patients. Additional interventions to increase syphilis screening rates are needed.
What Is Bipolar Disorder? A Guide to Hope and Recovery for African Americans
... Violence Signs of a Healthy Workplace Clifford Beers Society Social Self-Directed Care Program Take a Screen Mental ... Campus Minority Mental Health Workplace Wellness Clifford Beers Society Social Self-Directed Care Program Take a Screen Mental ...
Consistency of Recall for Deployment-Related Traumatic Brain Injury.
Alosco, Michael L; Aslan, Mihaela; Du, Mengtian; Ko, John; Grande, Laura; Proctor, Susan P; Concato, John; Vasterling, Jennifer J
2016-01-01
To examine the temporal consistency of self-reported deployment-related traumatic brain injury (TBI) and its association with posttraumatic stress disorder (PTSD) symptom severity. In-person interviews at US Army installations (postdeployment); phone interviews (long-term follow-up). A total of 378 US Army soldiers and veterans deployed to Iraq; 14.3% (n = 54) reported TBI with loss of consciousness during an index deployment. Participants were evaluated after returning from deployment and again 5 to 9 years later. Temporal consistency of TBI endorsement based on TBI screening interviews; PTSD Checklist, Civilian Version. The concordance of deployment-related TBI endorsement from the postdeployment to long-term follow-up assessment was moderate (κ = 0.53). Of the 54 participants reporting (predominantly mild) TBI occurring during an index deployment, 32 endorsed TBI inconsistently over time. More severe PTSD symptoms at postdeployment assessment were independently associated with discordant reporting (P = .0004); each 10-point increase in PCL scores increasing odds of discordance by 69% (odds ratio = 1.69; 95% confidence interval, 1.26-2.26). Deployment-related TBI may not be reported reliably over time, particularly among war-zone veterans with greater PTSD symptoms. Results of screening evaluations for TBI history should be viewed with caution in the context of PTSD symptom history.
Hart, C L; Smith, G Davey; Hole, D J; Hawthorne, V M
2006-03-01
To investigate how carboxyhaemoglobin concentration is related to smoking habit and to assess whether carboxyhaemoglobin concentration is related to mortality. Prospective cohort study. Residents of the towns of Renfrew and Paisley in Scotland. The whole Renfrew/Paisley study, conducted between 1972 and 1976, consisted of 7048 men and 8354 women aged 45-64 years. This study was based on 3372 men and 4192 women who were screened after the measurement of carboxyhaemoglobin concentration was introduced about halfway through the study. Deaths from coronary heart disease (CHD), stroke, chronic obstructive pulmonary disease (COPD), lung cancer, and all causes in 25 years after screening. Carboxyhaemoglobin concentration was related to self reported smoking and for each smoking category was higher in participants who reported inhaling than in those who reported not inhaling. Carboxyhaemoglobin concentration was positively related to all causes of mortality analysed (relative rates associated with a 1 SD (2.93) increase in carboxyhaemoglobin for all causes, CHD, stroke, COPD, and lung cancer were 1.26 (95% confidence interval (CI) 1.19 to 1.34), 1.19 (95% CI 1.13 to 1.26), 1.19 (95% CI 1.13 to 1.26), 1.64 (95% CI 1.47 to 1.84), and 1.69 (95% CI 1.60 to 1.79), respectively). Adjustment for self reported cigarette smoking attenuated the associations but they remained relatively strong. Self reported smoking data were validated by the objective measure of carboxyhaemoglobin concentration. Since carboxyhaemoglobin concentration remained associated with mortality after adjustment for smoking, carboxyhaemoglobin seems to capture more of the risk associated with smoking tobacco than does self reported tobacco consumption alone. Analysing mortality by self reported cigarette smoking underestimates the strength of association between smoking and mortality.
Holt, Cheryl L; Litaker, Mark S; Scarinci, Isabel C; Debnam, Katrina J; McDavid, Chastity; McNeal, Sandre F; Eloubeidi, Mohamad A; Crowther, Martha; Bolland, John; Martin, Michelle Y
2013-08-01
Colorectal cancer screening has clear benefits in terms of mortality reduction; however, it is still underutilized and especially among medically underserved populations, including African Americans, who also suffer a disproportionate colorectal cancer burden. This study consisted of a theory-driven (health belief model) spiritually based intervention aimed at increasing screening among African Americans through a community health advisor-led educational series in 16 churches. Using a randomized design, churches were assigned to receive either the spiritually based intervention or a nonspiritual comparison, which was the same in every way except that it did not contain spiritual/religious content and themes. Trained and certified peer community health advisors in each church led a series of two group educational sessions on colorectal cancer and screening. Study enrollees completed a baseline, 1-month, and 12-month follow-up survey at their churches. The interventions had significant pre-post impact on awareness of all four screening modalities, and self-report receipt of fecal occult blood test, flexible sigmoidoscopy, and colonoscopy. There were no significant study group differences in study outcomes, with the exception of fecal occult blood test utilization, whereas those in the nonspiritual intervention reported significantly greater pre-post change. Both of these community-engaged, theory-driven, culturally relevant approaches to increasing colorectal cancer awareness and screening appeared to have an impact on study outcomes. Although adding spiritual/religious themes to the intervention was appealing to the audience, it may not result in increased intervention efficacy.
Norwati, Daud; Harmy, Mohamed Yusoff; Norhayati, Mohd Noor; Amry, Abdul Rahim
2014-01-01
The incidence of colorectal cancer has been increasing in many Asian countries including Malaysia during the past few decades. A physician recommendation has been shown to be a major factor that motivates patients to undergo screening. The present study objectives were to describe the practice of colorectal cancer screening by primary care providers in Malaysia and to determine the barriers for not following recommendations. In this cross sectional study involving 132 primary care providers from 44 Primary Care clinics in West Malaysia, self-administered questionnaires which consisted of demographic data, qualification, background on the primary care clinic, practices on colorectal cancer screening and barriers to colorectal cancer screening were distributed. A total of 116 primary care providers responded making a response rate of 87.9%. About 21% recommended faecal occult blood test (FOBT) in more than 50% of their patients who were eligible. The most common barrier was "unavailability of the test". The two most common patient factors are "patient in a hurry" and "poor patient awareness". This study indicates that colorectal cancer preventive activities among primary care providers are still poor in Malaysia. This may be related to the low availability of the test in the primary care setting and poor awareness and understanding of the importance of colorectal cancer screening among patients. More awareness programmes are required for the public. In addition, primary care providers should be kept abreast with the latest recommendations and policy makers need to improve colorectal cancer screening services in health clinics.
A novel methodology for self-healing at the nanoscale in CNT/epoxy composites
NASA Astrophysics Data System (ADS)
Quigley, E.; Datta, S.; Chattopadhyay, A.
2016-04-01
Self-healing materials have the potential to repair induced damage and extend the service life of aerospace or civil components as well as prevent catastrophic failure. A novel technique to provide self-healing capabilities at the nanoscale in carbon nanotube/epoxy nanocomposites is presented in this paper. Carbon nanotubes (CNTs) functionalized with the healing agent (dicyclopentadiene) were used to fabricate self-healing CNT/epoxy nanocomposite films. The structure of CNTs was considered suitable for this application since they are nanosized, hollow, and provide a more consistent size distribution than polymeric nanocapsules. Specimens with different weight fractions of the functionalized CNTs were fabricated to explore the effect of weight fraction of functionalized CNTs on the extent of healing. Optical micrographs with different fluorescent filters showed partial or complete healing of damage approximately two to three weeks after damage was induced. Results indicate that by using CNTs to encapsulate a healing agent, crack growth in self-healing CNT/epoxy nanocomposites can be retarded, leading to safer materials that can autonomously repair itself.
Understanding breast cancer screening practices in Taiwan: a country with universal health care.
Wu, Tsu-Yin; Chung, Scott; Yeh, Ming-Chen; Chang, Shu-Chen; Hsieh, Hsing-Fang; Ha, Soo Ji
2012-01-01
While the incidence of breast cancer (BC) has been relatively low in Asian countries, it has been rising rapidly in Taiwan. Within the last decade, it has replaced cervical cancer as the most diagnosed cancer site for women. Nevertheless, there is a paucity of studies reporting the attitudes and practices of breast cancer screening among Chinese women. The aim of this study is to assess Taiwanese women's knowledge of and attitudes toward BC screening and to identify potential factors that may influence screening behavior. The study population consisted of a sample of 434 Taiwanese women aged 40 and older. Despite access to universal health care for Taiwanese women and the fact that a majority of the women had heard of the breast cancer screening (mammogram, clinical breast exams, etc.), the actual utilization of these screening modalities was relatively low. In the current study, the majority of women had never had mammograms or ultrasound in the past 5 years. The number one most reported barriers were "no time, " "forgetfulness, " "too cumbersome, " and "laziness, " followed by the perception of no need to get screened. In addition, the results revealed several areas of misconceptions or incorrect information perceived by study participants. Based on the results from the regression analysis, significant predictors of obtaining repeated screening modalities included age, coverage for screening, barriers, self-efficacy, intention, family/friends diagnosed with breast cancer. The findings from the current study provide the potential to build evidence-based programs to effectively plan and implement policies in order to raise awareness in breast cancer and promote BC screening in order to optimize health outcomes for women affected by this disease.
Lee, Kunsei; Kim, Hyeongsu; Lee, Jung Hyun; Jeong, Hyoseon; Shin, Soon Ae; Han, Taehwa; Seo, Young Lan; Yoo, Youngbum; Nam, Sang Eun; Park, Jong Heon; Park, Yoo Mi
2016-11-18
The purpose of this study was to determine the benefits and limitations of screening for breast cancer using mammography. Descriptive design with follow-up was used in the study. Data from breast cancer screening and health insurance claim data were used. The study population consisted of all participants in breast cancer screening from 2009 to 2014. Crude detection rate, positive predictive value and sensitivity and specificity of breast cancer screening and, incidence rate of interval cancer of the breast were calculated. The crude detection rate of breast cancer screening per 100,000 participants increased from 126.3 in 2009 to 182.1 in 2014. The positive predictive value of breast cancer screening per 100,000 positives increased from 741.2 in 2009 to 1,367.9 in 2014. The incidence rate of interval cancer of the breast per 100,000 negatives increased from 51.7 in 2009 to 76.3 in 2014. The sensitivities of screening for breast cancer were 74.6% in 2009 and 75.1% in 2014 and the specificities were 83.1% in 2009 and 85.7% in 2014. To increase the detection rate of breast cancer by breast cancer screening using mammography, the participation rate should be higher and an environment where accurate mammography and reading can be performed and reinforcement of quality control are required. To reduce the incidence rate of interval cancer of the breast, it will be necessary to educate women after their 20s to perform self-examination of the breast once a month regardless of participation in screening for breast cancer.
Georgiopoulos, Anna M; Friedman, Deborah; Porter, Elizabeth A; Krasner, Amy; Kakarala, Sheetal P; Glaeser, Breanna K; Napoleon, Siena C; Wozniak, Janet
2018-03-01
International guidelines recommend depression and anxiety screening in individuals with cystic fibrosis (CF), but Attention-Deficit Hyperactivity Disorder (ADHD) remains understudied. Adults with CF (n=53) were screened using the Adult ADHD Self-Report Scale-v1.1 Symptom Checklist (ASRS-v1.1), Cystic Fibrosis Questionnaire-Revised (CFQ-R), and a self-report measure of treatment adherence. Elevated ADHD symptoms on the ASRS-v1.1 screener were reported by 15% of participants. Self-reported adherence, Body Mass Index in kg/m 2 (BMI), and Forced Expiratory Volume in 1 Second, Percent Predicted (FEV1%pred) did not differ between participants with vs. without elevated ADHD scores. Three CFQ-R scales, Physical Functioning, Role Functioning, and Respiratory Symptoms, were significantly lower in participants with elevated ADHD screens (unadjusted p<0.05). This difference remained statistically significant for the Role Functioning and Respiratory Symptoms scales following correction for multiple comparisons. The highly specific screening tool ASRS-v1.1 can ascertain previously undetected ADHD symptoms in adults with CF. ADHD was substantially more prevalent than expected in this population. Elevated ASRS-v1.1 screens correlated with poorer Health-Related Quality of Life (HRQoL) in some domains, but not with BMI, FEV1%pred, or self-reported CF treatment adherence. Additional research will elucidate the impact of ADHD and its treatment on HRQoL, CF self-care and health outcomes. Copyright © 2017 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.
Knowledge-Based Methods To Train and Optimize Virtual Screening Ensembles
2016-01-01
Ensemble docking can be a successful virtual screening technique that addresses the innate conformational heterogeneity of macromolecular drug targets. Yet, lacking a method to identify a subset of conformational states that effectively segregates active and inactive small molecules, ensemble docking may result in the recommendation of a large number of false positives. Here, three knowledge-based methods that construct structural ensembles for virtual screening are presented. Each method selects ensembles by optimizing an objective function calculated using the receiver operating characteristic (ROC) curve: either the area under the ROC curve (AUC) or a ROC enrichment factor (EF). As the number of receptor conformations, N, becomes large, the methods differ in their asymptotic scaling. Given a set of small molecules with known activities and a collection of target conformations, the most resource intense method is guaranteed to find the optimal ensemble but scales as O(2N). A recursive approximation to the optimal solution scales as O(N2), and a more severe approximation leads to a faster method that scales linearly, O(N). The techniques are generally applicable to any system, and we demonstrate their effectiveness on the androgen nuclear hormone receptor (AR), cyclin-dependent kinase 2 (CDK2), and the peroxisome proliferator-activated receptor δ (PPAR-δ) drug targets. Conformations that consisted of a crystal structure and molecular dynamics simulation cluster centroids were used to form AR and CDK2 ensembles. Multiple available crystal structures were used to form PPAR-δ ensembles. For each target, we show that the three methods perform similarly to one another on both the training and test sets. PMID:27097522
Adhesion of a bimetallic interface. Ph.D. Thesis - Case Western Reserve Univ.; [for Al, Mg, and Zn
NASA Technical Reports Server (NTRS)
Ferrante, J.
1978-01-01
The Hohenberg-Kohn and Kohn-Sham formalisms are used to examine binding (binding energy as a function of separation) for combinations of the simple metals Al(111), Zn(0001), Mg(0001), and Na(110) in contact. Similar metal contacts between Al, Zn, Mg, and Na are examined self-consistently in an ab initio calculation using the Kohn-Sham formalism. Crystallinity is included using the Aschroft pseudopotential via first order perturbation theory for the electron-ion interaction; and the ion-ion interaction is included exactly via a lattice sum. Binding energy was determined both in the local-density approximation and including gradient corrections to the exchange and correlation energy. Binding was found in all cases. In dissimilar metal contacts, interfacial bonding was greater than that in the weaker material predicting the possibility of metallic transfer. The nonzero position of the energy minimum in like metal contacts is explained in terms of consistency between the Ashcroft pseudopotential and the bulk charge density. Good agreement with experimental surface energies is obtained in the self-consistent calculation when nonlocal terms are included.
Lumpkins, Cy; Cupertino, P; Young, K; Daley, C; Yeh, Hw; Greiner, Ka
2013-01-25
Ethnic and racial minority groups in the U.S. receive fewer colorectal cancer (CRC) screening tests and are less likely to be up-to-date with CRC screening than the population as a whole. Access, limited awareness of CRC and barriers may, in part, be responsible for inhibiting widespread adoption of CRC screening among racial and ethnic minority groups. The purpose of this study was to examine the role of self-efficacy, fatalism and CRC risk perception across racial and ethnic groups in a diverse sample. This study was a cross-sectional analysis from baseline measures gathered on a group of patients recruited into a trial to track colorectal cancer screening in underserved adults over 50. Out of 470 Participants, 42% were non-Hispanic; 27% Hispanic and 28% non-Hispanic White. Hispanic and non-Hispanic Blacks were more likely to have fatalistic beliefs about CRC than non-Hispanic Whites. Non-Hispanic Blacks perceived higher risk of getting colon cancer. Self-efficacy for completing CRC screening was higher among Non-Hispanic Blacks than among Hispanics. Racial and ethnic differences in risk perceptions, fatalism and self-efficacy should be taken into consideration in future CRC interventions with marginalized and uninsured populations.
Kuperman, Ethan F.; Tobin, Kristen; Kraschnewski, Jennifer L.
2014-01-01
Background Resident engagement in quality improvement is a requirement for graduate medical education, but the optimal means of instruction and evaluation of resident progress remain unknown. Objective To determine the accuracy of self-reported chart audits in measuring resident adherence to primary care clinical practice guidelines. Methods During the 2010–2011 academic year, second- and third-year internal medicine residents at a single, university hospital–based program performed chart audits on 10 patients from their primary care clinic to determine adherence to 16 US Preventive Services Task Force primary care guidelines. We compared residents' responses to independent audits of randomly selected patient charts by a single external reviewer. Results Self-reported data were collected by 18 second-year and 15 third-year residents for 330 patients. Independently, 70 patient charts were randomly selected for review by an external auditor. Overall guideline compliance was significantly higher on self-reported audits compared to external audits (82% versus 68%, P < .001). Of 16 guidelines, external audits found significantly lower rates of adherence for 5 (tetanus vaccination, osteoporosis screening, colon cancer screening, cholesterol screening, and obesity screening). Chlamydia screening was more common in audited charts than in self-reported data. Although third-year residents self-reported higher guideline adherence than second-year residents (86% versus 78%, P < .001), external audits for third-year residents found lower overall adherence (64% versus 72%, P = .040). Conclusions Residents' self-reported chart audits may significantly overestimate guideline adherence. Increased supervision and independent review appear necessary to accurately evaluate resident performance. PMID:26140117
Kuperman, Ethan F; Tobin, Kristen; Kraschnewski, Jennifer L
2014-12-01
Resident engagement in quality improvement is a requirement for graduate medical education, but the optimal means of instruction and evaluation of resident progress remain unknown. To determine the accuracy of self-reported chart audits in measuring resident adherence to primary care clinical practice guidelines. During the 2010-2011 academic year, second- and third-year internal medicine residents at a single, university hospital-based program performed chart audits on 10 patients from their primary care clinic to determine adherence to 16 US Preventive Services Task Force primary care guidelines. We compared residents' responses to independent audits of randomly selected patient charts by a single external reviewer. Self-reported data were collected by 18 second-year and 15 third-year residents for 330 patients. Independently, 70 patient charts were randomly selected for review by an external auditor. Overall guideline compliance was significantly higher on self-reported audits compared to external audits (82% versus 68%, P < .001). Of 16 guidelines, external audits found significantly lower rates of adherence for 5 (tetanus vaccination, osteoporosis screening, colon cancer screening, cholesterol screening, and obesity screening). Chlamydia screening was more common in audited charts than in self-reported data. Although third-year residents self-reported higher guideline adherence than second-year residents (86% versus 78%, P < .001), external audits for third-year residents found lower overall adherence (64% versus 72%, P = .040). Residents' self-reported chart audits may significantly overestimate guideline adherence. Increased supervision and independent review appear necessary to accurately evaluate resident performance.
Savitz, Samuel T.; Stearns, Sally C.; Zhou, Lei; Thudium, Emily; Alburikan, Khalid A.; Tran, Richard; Rodgers, Jo E.
2017-01-01
Objective Medicare Part D claims indicate medication purchased, but people who are not fully adherent may extend prescription use beyond the interval prescribed. This study assessed concordance between Part D claims and medication possession at a study visit in relation to self-reported medication adherence. Methods We matched Part D claims for six common medications to medications brought to a study visit in 2011–2013 for the Atherosclerosis Risk in Communities Study (ARIC). The combined data consisted of 3,027 medication events (claims, medications possessed or both) for 2,099 ARIC participants. Multinomial logistic regression estimated the association of concordance (Visit Only, Part D Only, or Both) with self-reported medication adherence while controlling for socio-demographic characteristics, veteran status, and availability under Generic Drug Discount Programs (GDDPs). Results Relative to participants with high adherence (p<0.05), medication events for participants with low adherence were approximately 25 percentage points less likely to match and more likely to be Visit Only. The results were similar but smaller in magnitude (approximately 2–3 percentage points) for participants with medium adherence. Compared to females, medication events for male veterans were approximately 11 percentage points less likely to match and more likely to be Visit Only. Events for medications available through GDDP were 3 percentage points more likely to be Visit Only. Conclusions Part D claims were substantially less likely to be concordant with medications possessed at study visit for participants with low self-reported adherence. This result supports the construction of adherence proxies such as proportion days covered using Part D claims. PMID:28221276