Sample records for generalized born implicit

  1. Calculation of Protein Heat Capacity from Replica-Exchange Molecular Dynamics Simulations with Different Implicit Solvent Models

    DTIC Science & Technology

    2008-10-30

    rigorous Poisson-based methods generally apply a Lee-Richards mo- lecular surface.9 This surface is considered the de facto description for continuum...definition and calculation of the Born radii. To evaluate the Born radii, two approximations are invoked. The first is the Coulomb field approximation (CFA...energy term, and depending on the particular GB formulation, higher-order non- Coulomb correction terms may be added to the Born radii to account for the

  2. Treecode-based generalized Born method

    NASA Astrophysics Data System (ADS)

    Xu, Zhenli; Cheng, Xiaolin; Yang, Haizhao

    2011-02-01

    We have developed a treecode-based O(Nlog N) algorithm for the generalized Born (GB) implicit solvation model. Our treecode-based GB (tGB) is based on the GBr6 [J. Phys. Chem. B 111, 3055 (2007)], an analytical GB method with a pairwise descreening approximation for the R6 volume integral expression. The algorithm is composed of a cutoff scheme for the effective Born radii calculation, and a treecode implementation of the GB charge-charge pair interactions. Test results demonstrate that the tGB algorithm can reproduce the vdW surface based Poisson solvation energy with an average relative error less than 0.6% while providing an almost linear-scaling calculation for a representative set of 25 proteins with different sizes (from 2815 atoms to 65456 atoms). For a typical system of 10k atoms, the tGB calculation is three times faster than the direct summation as implemented in the original GBr6 model. Thus, our tGB method provides an efficient way for performing implicit solvent GB simulations of larger biomolecular systems at longer time scales.

  3. Optimization of the GBMV2 implicit solvent force field for accurate simulation of protein conformational equilibria.

    PubMed

    Lee, Kuo Hao; Chen, Jianhan

    2017-06-15

    Accurate treatment of solvent environment is critical for reliable simulations of protein conformational equilibria. Implicit treatment of solvation, such as using the generalized Born (GB) class of models arguably provides an optimal balance between computational efficiency and physical accuracy. Yet, GB models are frequently plagued by a tendency to generate overly compact structures. The physical origins of this drawback are relatively well understood, and the key to a balanced implicit solvent protein force field is careful optimization of physical parameters to achieve a sufficient level of cancellation of errors. The latter has been hampered by the difficulty of generating converged conformational ensembles of non-trivial model proteins using the popular replica exchange sampling technique. Here, we leverage improved sampling efficiency of a newly developed multi-scale enhanced sampling technique to re-optimize the generalized-Born with molecular volume (GBMV2) implicit solvent model with the CHARMM36 protein force field. Recursive optimization of key GBMV2 parameters (such as input radii) and protein torsion profiles (via the CMAP torsion cross terms) has led to a more balanced GBMV2 protein force field that recapitulates the structures and stabilities of both helical and β-hairpin model peptides. Importantly, this force field appears to be free of the over-compaction bias, and can generate structural ensembles of several intrinsically disordered proteins of various lengths that seem highly consistent with available experimental data. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  4. Discrimination of Native-like States of Membrane Proteins with Implicit Membrane-based Scoring Functions.

    PubMed

    Dutagaci, Bercem; Wittayanarakul, Kitiyaporn; Mori, Takaharu; Feig, Michael

    2017-06-13

    A scoring protocol based on implicit membrane-based scoring functions and a new protocol for optimizing the positioning of proteins inside the membrane was evaluated for its capacity to discriminate native-like states from misfolded decoys. A decoy set previously established by the Baker lab (Proteins: Struct., Funct., Genet. 2006, 62, 1010-1025) was used along with a second set that was generated to cover higher resolution models. The Implicit Membrane Model 1 (IMM1), IMM1 model with CHARMM 36 parameters (IMM1-p36), generalized Born with simple switching (GBSW), and heterogeneous dielectric generalized Born versions 2 (HDGBv2) and 3 (HDGBv3) were tested along with the new HDGB van der Waals (HDGBvdW) model that adds implicit van der Waals contributions to the solvation free energy. For comparison, scores were also calculated with the distance-scaled finite ideal-gas reference (DFIRE) scoring function. Z-scores for native state discrimination, energy vs root-mean-square deviation (RMSD) correlations, and the ability to select the most native-like structures as top-scoring decoys were evaluated to assess the performance of the scoring functions. Ranking of the decoys in the Baker set that were relatively far from the native state was challenging and dominated largely by packing interactions that were captured best by DFIRE with less benefit of the implicit membrane-based models. Accounting for the membrane environment was much more important in the second decoy set where especially the HDGB-based scoring functions performed very well in ranking decoys and providing significant correlations between scores and RMSD, which shows promise for improving membrane protein structure prediction and refinement applications. The new membrane structure scoring protocol was implemented in the MEMScore web server ( http://feiglab.org/memscore ).

  5. On the Helix Propensity in Generalized Born Solvent Descriptions of Modeling the Dark Proteome

    PubMed Central

    Olson, Mark A.

    2017-01-01

    Intrinsically disordered proteins that populate the so-called “Dark Proteome” offer challenging benchmarks of atomistic simulation methods to accurately model conformational transitions on a multidimensional energy landscape. This work explores the application of parallel tempering with implicit solvent models as a computational framework to capture the conformational ensemble of an intrinsically disordered peptide derived from the Ebola virus protein VP35. A recent X-ray crystallographic study reported a protein-peptide interface where the VP35 peptide underwent a folding transition from a disordered form to a helix-β-turn-helix topological fold upon molecular association with the Ebola protein NP. An assessment is provided of the accuracy of two generalized Born solvent models (GBMV2 and GBSW2) using the CHARMM force field and applied with temperature-based replica exchange dynamics to calculate the disorder propensity of the peptide and its probability density of states in a continuum solvent. A further comparison is presented of applying an explicit/implicit solvent hybrid replica exchange simulation of the peptide to determine the effect of modeling water interactions at the all-atom resolution. PMID:28197405

  6. On the Helix Propensity in Generalized Born Solvent Descriptions of Modeling the Dark Proteome.

    PubMed

    Olson, Mark A

    2017-01-01

    Intrinsically disordered proteins that populate the so-called "Dark Proteome" offer challenging benchmarks of atomistic simulation methods to accurately model conformational transitions on a multidimensional energy landscape. This work explores the application of parallel tempering with implicit solvent models as a computational framework to capture the conformational ensemble of an intrinsically disordered peptide derived from the Ebola virus protein VP35. A recent X-ray crystallographic study reported a protein-peptide interface where the VP35 peptide underwent a folding transition from a disordered form to a helix-β-turn-helix topological fold upon molecular association with the Ebola protein NP. An assessment is provided of the accuracy of two generalized Born solvent models (GBMV2 and GBSW2) using the CHARMM force field and applied with temperature-based replica exchange dynamics to calculate the disorder propensity of the peptide and its probability density of states in a continuum solvent. A further comparison is presented of applying an explicit/implicit solvent hybrid replica exchange simulation of the peptide to determine the effect of modeling water interactions at the all-atom resolution.

  7. Molecular Dynamics based on a Generalized Born solvation model: application to protein folding

    NASA Astrophysics Data System (ADS)

    Onufriev, Alexey

    2004-03-01

    An accurate description of the aqueous environment is essential for realistic biomolecular simulations, but may become very expensive computationally. We have developed a version of the Generalized Born model suitable for describing large conformational changes in macromolecules. The model represents the solvent implicitly as continuum with the dielectric properties of water, and include charge screening effects of salt. The computational cost associated with the use of this model in Molecular Dynamics simulations is generally considerably smaller than the cost of representing water explicitly. Also, compared to traditional Molecular Dynamics simulations based on explicit water representation, conformational changes occur much faster in implicit solvation environment due to the absence of viscosity. The combined speed-up allow one to probe conformational changes that occur on much longer effective time-scales. We apply the model to folding of a 46-residue three helix bundle protein (residues 10-55 of protein A, PDB ID 1BDD). Starting from an unfolded structure at 450 K, the protein folds to the lowest energy state in 6 ns of simulation time, which takes about a day on a 16 processor SGI machine. The predicted structure differs from the native one by 2.4 A (backbone RMSD). Analysis of the structures seen on the folding pathway reveals details of the folding process unavailable form experiment.

  8. The Generalized Born solvation model: What is it?

    NASA Astrophysics Data System (ADS)

    Onufriev, Alexey

    2004-03-01

    Implicit solvation models provide, for many applications, an effective way of describing the electrostatic effects of aqueous solvation. Here we outline the main approximations behind the popular Generalized Born solvation model. We show how its accuracy, relative to the Poisson-Boltzmann treatment, can be significantly improved in a computationally inexpensive manner to make the model useful in the studies of large-scale conformational transitions at the atomic level. The improved model is tested in a molecular dynamics simulation of folding of a 46-residue (three helix bundle) protein. Starting from an extended structure at 450K, the protein folds to the lowest energy conformation within 6 ns of simulation time, and the predicted structure differs from the native one by 2.4 A (backbone RMSD).

  9. Implicit and explicit motor sequence learning in children born very preterm.

    PubMed

    Jongbloed-Pereboom, Marjolein; Janssen, Anjo J W M; Steiner, K; Steenbergen, Bert; Nijhuis-van der Sanden, Maria W G

    2017-01-01

    Motor skills can be learned explicitly (dependent on working memory (WM)) or implicitly (relatively independent of WM). Children born very preterm (VPT) often have working memory deficits. Explicit learning may be compromised in these children. This study investigated implicit and explicit motor learning and the role of working memory in VPT children and controls. Three groups (6-9 years) participated: 20 VPT children with motor problems, 20 VPT children without motor problems, and 20 controls. A nine button sequence was learned implicitly (pressing the lighted button as quickly as possible) and explicitly (discovering the sequence via trial-and-error). Children learned implicitly and explicitly, evidenced by decreased movement duration of the sequence over time. In the explicit condition, children also reduced the number of errors over time. Controls made more errors than VPT children without motor problems. Visual WM had positive effects on both explicit and implicit performance. VPT birth and low motor proficiency did not negatively affect implicit or explicit learning. Visual WM was positively related to both implicit and explicit performance, but did not influence learning curves. These findings question the theoretical difference between implicit and explicit learning and the proposed role of visual WM therein. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Refinement of Generalized Born Implicit Solvation Parameters for Nucleic Acids and their Complexes with Proteins

    PubMed Central

    Nguyen, Hai; Pérez, Alberto; Bermeo, Sherry; Simmerling, Carlos

    2016-01-01

    The Generalized Born (GB) implicit solvent model has undergone significant improvements in accuracy for modeling of proteins and small molecules. However, GB still remains a less widely explored option for nucleic acid simulations, in part because fast GB models are often unable to maintain stable nucleic acid structures, or they introduce structural bias in proteins, leading to difficulty in application of GB models in simulations of protein-nucleic acid complexes. Recently, GB-neck2 was developed to improve the behavior of protein simulations. In an effort to create a more accurate model for nucleic acids, a similar procedure to the development of GB-neck2 is described here for nucleic acids. The resulting parameter set significantly reduces absolute and relative energy error relative to Poisson Boltzmann for both nucleic acids and nucleic acid-protein complexes, when compared to its predecessor GB-neck model. This improvement in solvation energy calculation translates to increased structural stability for simulations of DNA and RNA duplexes, quadruplexes, and protein-nucleic acid complexes. The GB-neck2 model also enables successful folding of small DNA and RNA hairpins to near native structures as determined from comparison with experiment. The functional form and all required parameters are provided here and also implemented in the AMBER software. PMID:26574454

  11. On the Helix Propensity in Generalized Born Solvent Descriptions of Modeling the Dark Proteome

    DTIC Science & Technology

    2017-01-10

    benchmarks of conformational sampling methods and their all-atom force fields plus solvent descriptions to accurately model structural transitions on a...atom simulations of proteins is the replacement of explicit water interactions with a continuum description of treating implicitly the bulk physical... structure was reported by Amarasinghe and coworkers (Leung et al., 2015) of the Ebola nucleoprotein NP in complex with a 28-residue peptide extracted

  12. Prediction of Protein-Peptide Interactions: Application of the XPairIT to Anthrax Lethal Factor and Substrates

    DTIC Science & Technology

    2013-09-01

    hydrogen bonds in Tyrosine-containing peptides. Dalkas et al[7] used docking and molecular dynamics simulations to study a variety of MAPKK-based... simulated using NAMD molecular dynamics and the CHARMM[20] forcefield at 300K and employing the Generalized Born Implicit Solvent (GBIS[21]) with the...which were reported in Section 2. Specifically, after a ~10ns molecular dynamics simulation in TIP3 explicit water, significant motion of domains III

  13. Investigating the Effect of Charge Hydration Asymmetry and Incorporating it in Continuum Solvation Framework

    NASA Astrophysics Data System (ADS)

    Mukhopadhyay, Abhishek

    One of the essential requirements of biomolecular modeling is an accurate description of water as a solvent. The challenge is to make this description computationally facile - reasonably fast, simple, robust and easy to incorporate into existing software packages, yet accurate. The most rigorous procedure to model the effect of aqueous solvent is to explicitly model every water molecule in the system. For many practical applications, this approach is computationally too intense, as the number of required water atoms is on an average at least one order of magnitude larger than the number of atoms of the molecule of interest. Implicit solvent models, in which solvent molecules are replaced by a continuous dielectric, have become a popular alternative to explicit solvent methods. However, implicit solvation models often lack various microscopic details which are crucial for accuracy. One such missing effect that is currently missing from popular implicit models is the so called effect of charge hydration asymmetry (CHA). The missing effect of charge hydration asymmetry - the asymmetric response of water upon the sign of solute charge - manifests a characteristic, strong dependence of solvation free energies on the sign of solute charge. Here, we incorporate this missing effect into the continuum solvation framework via the conceptually simplest Born equation and also in the generalized Born model. We identify the key electric multipole moments of model water molecules critical for the various degrees of CHA effect observed in studies based on molecular dynamics simulations using different rigid water models. We then use this gained insight to incorporate this effect first into the Born model and then into the generalized Born model. The proposed framework significantly improves accuracy of the hydration free energy estimates tested on a comprehensive set of varied molecular solutes - monovalent and divalent ions, small drug-like molecules, charged and uncharged amino acid dipeptides, and small proteins. We finally develop a methodology to resolve the issue with unacceptably large uncertainty that stems from a variety of fundamental and technical difficulties in experimental quantification of CHA from charged solutes. Using the proposed corrections in the continuum framework, we untangle the charge-asymmetric response of water from its symmetric response, and further circumvent the difficulties by extracting accurate estimate propensity of water to cause CHA from accurate experimental hydration free energies of neutral polar molecules. We show that the asymmetry in water's response is strong, about 50% of the symmetric response.

  14. Can a continuum solvent model reproduce the free energy landscape of a -hairpin folding in water?

    NASA Astrophysics Data System (ADS)

    Zhou, Ruhong; Berne, Bruce J.

    2002-10-01

    The folding free energy landscape of the C-terminal -hairpin of protein G is explored using the surface-generalized Born (SGB) implicit solvent model, and the results are compared with the landscape from an earlier study with explicit solvent model. The OPLSAA force field is used for the -hairpin in both implicit and explicit solvent simulations, and the conformational space sampling is carried out with a highly parallel replica-exchange method. Surprisingly, we find from exhaustive conformation space sampling that the free energy landscape from the implicit solvent model is quite different from that of the explicit solvent model. In the implicit solvent model some nonnative states are heavily overweighted, and more importantly, the lowest free energy state is no longer the native -strand structure. An overly strong salt-bridge effect between charged residues (E42, D46, D47, E56, and K50) is found to be responsible for this behavior in the implicit solvent model. Despite this, we find that the OPLSAA/SGB energies of all the nonnative structures are higher than that of the native structure; thus the OPLSAA/SGB energy is still a good scoring function for structure prediction for this -hairpin. Furthermore, the -hairpin population at 282 K is found to be less than 40% from the implicit solvent model, which is much smaller than the 72% from the explicit solvent model and 80% from experiment. On the other hand, both implicit and explicit solvent simulations with the OPLSAA force field exhibit no meaningful helical content during the folding process, which is in contrast to some very recent studies using other force fields.

  15. Can a continuum solvent model reproduce the free energy landscape of a β-hairpin folding in water?

    PubMed Central

    Zhou, Ruhong; Berne, Bruce J.

    2002-01-01

    The folding free energy landscape of the C-terminal β-hairpin of protein G is explored using the surface-generalized Born (SGB) implicit solvent model, and the results are compared with the landscape from an earlier study with explicit solvent model. The OPLSAA force field is used for the β-hairpin in both implicit and explicit solvent simulations, and the conformational space sampling is carried out with a highly parallel replica-exchange method. Surprisingly, we find from exhaustive conformation space sampling that the free energy landscape from the implicit solvent model is quite different from that of the explicit solvent model. In the implicit solvent model some nonnative states are heavily overweighted, and more importantly, the lowest free energy state is no longer the native β-strand structure. An overly strong salt-bridge effect between charged residues (E42, D46, D47, E56, and K50) is found to be responsible for this behavior in the implicit solvent model. Despite this, we find that the OPLSAA/SGB energies of all the nonnative structures are higher than that of the native structure; thus the OPLSAA/SGB energy is still a good scoring function for structure prediction for this β-hairpin. Furthermore, the β-hairpin population at 282 K is found to be less than 40% from the implicit solvent model, which is much smaller than the 72% from the explicit solvent model and ≈80% from experiment. On the other hand, both implicit and explicit solvent simulations with the OPLSAA force field exhibit no meaningful helical content during the folding process, which is in contrast to some very recent studies using other force fields. PMID:12242327

  16. Can a continuum solvent model reproduce the free energy landscape of a beta -hairpin folding in water?

    PubMed

    Zhou, Ruhong; Berne, Bruce J

    2002-10-01

    The folding free energy landscape of the C-terminal beta-hairpin of protein G is explored using the surface-generalized Born (SGB) implicit solvent model, and the results are compared with the landscape from an earlier study with explicit solvent model. The OPLSAA force field is used for the beta-hairpin in both implicit and explicit solvent simulations, and the conformational space sampling is carried out with a highly parallel replica-exchange method. Surprisingly, we find from exhaustive conformation space sampling that the free energy landscape from the implicit solvent model is quite different from that of the explicit solvent model. In the implicit solvent model some nonnative states are heavily overweighted, and more importantly, the lowest free energy state is no longer the native beta-strand structure. An overly strong salt-bridge effect between charged residues (E42, D46, D47, E56, and K50) is found to be responsible for this behavior in the implicit solvent model. Despite this, we find that the OPLSAA/SGB energies of all the nonnative structures are higher than that of the native structure; thus the OPLSAA/SGB energy is still a good scoring function for structure prediction for this beta-hairpin. Furthermore, the beta-hairpin population at 282 K is found to be less than 40% from the implicit solvent model, which is much smaller than the 72% from the explicit solvent model and approximately equal 80% from experiment. On the other hand, both implicit and explicit solvent simulations with the OPLSAA force field exhibit no meaningful helical content during the folding process, which is in contrast to some very recent studies using other force fields.

  17. Simulating botulinum neurotoxin with constant pH molecular dynamics in Generalized Born implicit solvent

    NASA Astrophysics Data System (ADS)

    Chen, Yongzhi; Chen, Xin; Deng, Yuefan

    2007-07-01

    A new method was proposed by Mongan et al. for constant pH molecular dynamics simulation and was implemented in AMBER 8 package. Protonation states are modeled with different charge sets, and titrating residues are sampled from a Boltzmann distribution of protonation states. The simulation periodically adopts Monte Carlo sampling based on Generalized Born (GB) derived energies. However, when this approach was applied to a bio-toxin, Botulinum Neurotoxin Type A (BoNT/A) at pH 4.4, 4.7, 5.0, 6.8 and 7.2, the pK predictions yielded by the method were inconsistent with the experimental values. The systems being simulated were divergent. Furthermore, the system behaviors in a very weak acidic solution (pH 6.8) and in a very weak basic solution (pH 7.2) were significantly different from the neutral case (pH 7.0). Hence, we speculate this method may require further study for modeling large biomolecule.

  18. Search for Length Dependent Stable Structures of Polyglutamaine Proteins with Replica Exchange Molecular Dynamic

    NASA Astrophysics Data System (ADS)

    Kluber, Alexander; Hayre, Robert; Cox, Daniel

    2012-02-01

    Motivated by the need to find beta-structure aggregation nuclei for the polyQ diseases such as Huntington's, we have undertaken a search for length dependent structure in model polyglutamine proteins. We use the Onufriev-Bashford-Case (OBC) generalized Born implicit solvent GPU based AMBER11 molecular dynamics with the parm96 force field coupled with a replica exchange method to characterize monomeric strands of polyglutamine as a function of chain length and temperature. This force field and solvation method has been shown among other methods to accurately reproduce folded metastability in certain small peptides, and to yield accurately de novo folded structures in a millisecond time-scale protein. Using GPU molecular dynamics we can sample out into the microsecond range. Additionally, explicit solvent runs will be used to verify results from the implicit solvent runs. We will assess order using measures of secondary structure and hydrogen bond content.

  19. Explicit ions/implicit water generalized Born model for nucleic acids

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

    Tolokh, Igor S.; Thomas, Dennis G.; Onufriev, Alexey V.

    Ion atmosphere around highly charged nucleic acid molecules plays a significant role in their dynamics, structure and interactions. Here we utilized the implicit solvent framework to develop a model for the explicit treatment of ions interacting with nucleic acid molecules. The proposed explicit ions/implicit water model is based on a significantly modified generalized Born (GB) model, and utilizes a non-standard approach to defining the solute/solvent dielectric boundary. Specifically, the model includes modifications to the GB interaction terms for the case of multiple interacting solutes – disconnected dielectric boundary around the solute-ion or ion-ion pairs. Fully analytical description of all energymore » components for charge-charge interactions is provided. The effectiveness of the approach is demonstrated by calculating the potential of mean force (PMF) for Na+-Cl− ion pair and by carrying out a set of Monte Carlo (MC) simulations of mono- and trivalent ions interacting with DNA and RNA duplexes. The monovalent (Na+) and trivalent (CoHex3+) counterion distributions predicted by the model are in close quantitative agreement with all-atom explicit water molecular dynamics simulations used as reference. Expressed in the units of energy, the maximum deviations of local ion concentrations from the reference are within kBT. The proposed explicit ions/implicit water GB model is able to resolve subtle features and differences of CoHex distributions around DNA and RNA duplexes. These features include preferential CoHex binding inside the major groove of RNA duplex, in contrast to CoHex biding at the "external" surface of the sugar-phosphate backbone of DNA duplex; these differences in the counterion binding patters were shown earlier to be responsible for the observed drastic differences in condensation propensities between short DNA and RNA duplexes. MC simulations of CoHex ions interacting with homopolymeric poly(dA·dT) DNA duplex with modified (de-methylated) and native Thymine bases are used to explore the physics behind CoHex-Thymine interactions. The simulations suggest that the ion desolvation penalty due to proximity to the low dielectric volume of the methyl group can contribute significantly to CoHex-Thymine interactions. Compared to the steric repulsion between the ion and the methyl group, the desolvation penalty interaction has a longer range, and may be important to consider in the context of methylation effects on DNA condensation.« less

  20. Explicit ions/implicit water generalized Born model for nucleic acids

    NASA Astrophysics Data System (ADS)

    Tolokh, Igor S.; Thomas, Dennis G.; Onufriev, Alexey V.

    2018-05-01

    The ion atmosphere around highly charged nucleic acid molecules plays a significant role in their dynamics, structure, and interactions. Here we utilized the implicit solvent framework to develop a model for the explicit treatment of ions interacting with nucleic acid molecules. The proposed explicit ions/implicit water model is based on a significantly modified generalized Born (GB) model and utilizes a non-standard approach to define the solute/solvent dielectric boundary. Specifically, the model includes modifications to the GB interaction terms for the case of multiple interacting solutes—disconnected dielectric boundary around the solute-ion or ion-ion pairs. A fully analytical description of all energy components for charge-charge interactions is provided. The effectiveness of the approach is demonstrated by calculating the potential of mean force for Na+-Cl- ion pair and by carrying out a set of Monte Carlo (MC) simulations of mono- and trivalent ions interacting with DNA and RNA duplexes. The monovalent (Na+) and trivalent (CoHex3+) counterion distributions predicted by the model are in close quantitative agreement with all-atom explicit water molecular dynamics simulations used as reference. Expressed in the units of energy, the maximum deviations of local ion concentrations from the reference are within kBT. The proposed explicit ions/implicit water GB model is able to resolve subtle features and differences of CoHex distributions around DNA and RNA duplexes. These features include preferential CoHex binding inside the major groove of the RNA duplex, in contrast to CoHex biding at the "external" surface of the sugar-phosphate backbone of the DNA duplex; these differences in the counterion binding patters were earlier shown to be responsible for the observed drastic differences in condensation propensities between short DNA and RNA duplexes. MC simulations of CoHex ions interacting with the homopolymeric poly(dA.dT) DNA duplex with modified (de-methylated) and native thymine bases are used to explore the physics behind CoHex-thymine interactions. The simulations suggest that the ion desolvation penalty due to proximity to the low dielectric volume of the methyl group can contribute significantly to CoHex-thymine interactions. Compared to the steric repulsion between the ion and the methyl group, the desolvation penalty interaction has a longer range and may be important to consider in the context of methylation effects on DNA condensation.

  1. Routine Microsecond Molecular Dynamics Simulations with AMBER on GPUs. 1. Generalized Born

    PubMed Central

    2012-01-01

    We present an implementation of generalized Born implicit solvent all-atom classical molecular dynamics (MD) within the AMBER program package that runs entirely on CUDA enabled NVIDIA graphics processing units (GPUs). We discuss the algorithms that are used to exploit the processing power of the GPUs and show the performance that can be achieved in comparison to simulations on conventional CPU clusters. The implementation supports three different precision models in which the contributions to the forces are calculated in single precision floating point arithmetic but accumulated in double precision (SPDP), or everything is computed in single precision (SPSP) or double precision (DPDP). In addition to performance, we have focused on understanding the implications of the different precision models on the outcome of implicit solvent MD simulations. We show results for a range of tests including the accuracy of single point force evaluations and energy conservation as well as structural properties pertainining to protein dynamics. The numerical noise due to rounding errors within the SPSP precision model is sufficiently large to lead to an accumulation of errors which can result in unphysical trajectories for long time scale simulations. We recommend the use of the mixed-precision SPDP model since the numerical results obtained are comparable with those of the full double precision DPDP model and the reference double precision CPU implementation but at significantly reduced computational cost. Our implementation provides performance for GB simulations on a single desktop that is on par with, and in some cases exceeds, that of traditional supercomputers. PMID:22582031

  2. I can do that: the impact of implicit theories on leadership role model effectiveness.

    PubMed

    Hoyt, Crystal L; Burnette, Jeni L; Innella, Audrey N

    2012-02-01

    This research investigates the role of implicit theories in influencing the effectiveness of successful role models in the leadership domain. Across two studies, the authors test the prediction that incremental theorists ("leaders are made") compared to entity theorists ("leaders are born") will respond more positively to being presented with a role model before undertaking a leadership task. In Study 1, measuring people's naturally occurring implicit theories of leadership, the authors showed that after being primed with a role model, incremental theorists reported greater leadership confidence and less anxious-depressed affect than entity theorists following the leadership task. In Study 2, the authors demonstrated the causal role of implicit theories by manipulating participants' theory of leadership ability. They replicated the findings from Study 1 and demonstrated that identification with the role model mediated the relationship between implicit theories and both confidence and affect. In addition, incremental theorists outperformed entity theorists on the leadership task.

  3. A strategy for reducing gross errors in the generalized Born models of implicit solvation

    PubMed Central

    Onufriev, Alexey V.; Sigalov, Grigori

    2011-01-01

    The “canonical” generalized Born (GB) formula [C. Still, A. Tempczyk, R. C. Hawley, and T. Hendrickson, J. Am. Chem. Soc. 112, 6127 (1990)] is known to provide accurate estimates for total electrostatic solvation energies ΔGel of biomolecules if the corresponding effective Born radii are accurate. Here we show that even if the effective Born radii are perfectly accurate, the canonical formula still exhibits significant number of gross errors (errors larger than 2kBT relative to numerical Poisson equation reference) in pairwise interactions between individual atomic charges. Analysis of exact analytical solutions of the Poisson equation (PE) for several idealized nonspherical geometries reveals two distinct spatial modes of the PE solution; these modes are also found in realistic biomolecular shapes. The canonical GB Green function misses one of two modes seen in the exact PE solution, which explains the observed gross errors. To address the problem and reduce gross errors of the GB formalism, we have used exact PE solutions for idealized nonspherical geometries to suggest an alternative analytical Green function to replace the canonical GB formula. The proposed functional form is mathematically nearly as simple as the original, but depends not only on the effective Born radii but also on their gradients, which allows for better representation of details of nonspherical molecular shapes. In particular, the proposed functional form captures both modes of the PE solution seen in nonspherical geometries. Tests on realistic biomolecular structures ranging from small peptides to medium size proteins show that the proposed functional form reduces gross pairwise errors in all cases, with the amount of reduction varying from more than an order of magnitude for small structures to a factor of 2 for the largest ones. PMID:21528947

  4. Improving the Efficiency of Non-equilibrium Sampling in the Aqueous Environment via Implicit-Solvent Simulations.

    PubMed

    Liu, Hui; Chen, Fu; Sun, Huiyong; Li, Dan; Hou, Tingjun

    2017-04-11

    By means of estimators based on non-equilibrium work, equilibrium free energy differences or potentials of mean force (PMFs) of a system of interest can be computed from biased molecular dynamics (MD) simulations. The approach, however, is often plagued by slow conformational sampling and poor convergence, especially when the solvent effects are taken into account. Here, as a possible way to alleviate the problem, several widely used implicit-solvent models, which are derived from the analytic generalized Born (GB) equation and implemented in the AMBER suite of programs, were employed in free energy calculations based on non-equilibrium work and evaluated for their abilities to emulate explicit water. As a test case, pulling MD simulations were carried out on an alanine polypeptide with different solvent models and protocols, followed by comparisons of the reconstructed PMF profiles along the unfolding coordinate. The results show that when employing the non-equilibrium work method, sampling with an implicit-solvent model is several times faster and, more importantly, converges more rapidly than that with explicit water due to reduction of dissipation. Among the assessed GB models, the Neck variants outperform the OBC and HCT variants in terms of accuracy, whereas their computational costs are comparable. In addition, for the best-performing models, the impact of the solvent-accessible surface area (SASA) dependent nonpolar solvation term was also examined. The present study highlights the advantages of implicit-solvent models for non-equilibrium sampling.

  5. Peptoid conformational free energy landscapes from implicit-solvent molecular simulations in AMBER.

    PubMed

    Voelz, Vincent A; Dill, Ken A; Chorny, Ilya

    2011-01-01

    To test the accuracy of existing AMBER force field models in predicting peptoid conformation and dynamics, we simulated a set of model peptoid molecules recently examined by Butterfoss et al. (JACS 2009, 131, 16798-16807) using QM methods as well as three peptoid sequences with experimentally determined structures. We found that AMBER force fields, when used with a Generalized Born/Surface Area (GBSA) implicit solvation model, could accurately reproduce the peptoid torsional landscape as well as the major conformers of known peptoid structures. Enhanced sampling by replica exchange molecular dynamics (REMD) using temperatures from 300 to 800 K was used to sample over cis-trans isomerization barriers. Compared to (Nrch)5 and cyclo-octasarcosyl, the free energy of N-(2-nitro-3-hydroxyl phenyl)glycine-N-(phenyl)glycine has the most "foldable" free energy landscape, due to deep trans-amide minima dictated by N-aryl sidechains. For peptoids with (S)-N (1-phenylethyl) (Nspe) side chains, we observe a discrepancy in backbone dihedral propensities between molecular simulations and QM calculations, which may be due to force field effects or the inability to capture n --> n* interactions. For these residues, an empirical phi-angle biasing potential can "rescue" the backbone propensities seen in QM. This approach can serve as a general strategy for addressing force fields without resorting to a complete reparameterization. Overall, this study demonstrates the utility of implicit-solvent REMD simulations for efficient sampling to predict peptoid conformational landscapes, providing a potential tool for first-principles design of sequences with specific folding properties.

  6. Virtual screening using molecular simulations.

    PubMed

    Yang, Tianyi; Wu, Johnny C; Yan, Chunli; Wang, Yuanfeng; Luo, Ray; Gonzales, Michael B; Dalby, Kevin N; Ren, Pengyu

    2011-06-01

    Effective virtual screening relies on our ability to make accurate prediction of protein-ligand binding, which remains a great challenge. In this work, utilizing the molecular-mechanics Poisson-Boltzmann (or Generalized Born) surface area approach, we have evaluated the binding affinity of a set of 156 ligands to seven families of proteins, trypsin β, thrombin α, cyclin-dependent kinase (CDK), cAMP-dependent kinase (PKA), urokinase-type plasminogen activator, β-glucosidase A, and coagulation factor Xa. The effect of protein dielectric constant in the implicit-solvent model on the binding free energy calculation is shown to be important. The statistical correlations between the binding energy calculated from the implicit-solvent approach and experimental free energy are in the range of 0.56-0.79 across all the families. This performance is better than that of typical docking programs especially given that the latter is directly trained using known binding data whereas the molecular mechanics is based on general physical parameters. Estimation of entropic contribution remains the barrier to accurate free energy calculation. We show that the traditional rigid rotor harmonic oscillator approximation is unable to improve the binding free energy prediction. Inclusion of conformational restriction seems to be promising but requires further investigation. On the other hand, our preliminary study suggests that implicit-solvent based alchemical perturbation, which offers explicit sampling of configuration entropy, can be a viable approach to significantly improve the prediction of binding free energy. Overall, the molecular mechanics approach has the potential for medium to high-throughput computational drug discovery. Copyright © 2011 Wiley-Liss, Inc.

  7. Comparison of MM/GBSA calculations based on explicit and implicit solvent simulations.

    PubMed

    Godschalk, Frithjof; Genheden, Samuel; Söderhjelm, Pär; Ryde, Ulf

    2013-05-28

    Molecular mechanics with generalised Born and surface area solvation (MM/GBSA) is a popular method to calculate the free energy of the binding of ligands to proteins. It involves molecular dynamics (MD) simulations with an explicit solvent of the protein-ligand complex to give a set of snapshots for which energies are calculated with an implicit solvent. This change in the solvation method (explicit → implicit) would strictly require that the energies are reweighted with the implicit-solvent energies, which is normally not done. In this paper we calculate MM/GBSA energies with two generalised Born models for snapshots generated by the same methods or by explicit-solvent simulations for five synthetic N-acetyllactosamine derivatives binding to galectin-3. We show that the resulting energies are very different both in absolute and relative terms, showing that the change in the solvent model is far from innocent and that standard MM/GBSA is not a consistent method. The ensembles generated with the various solvent models are quite different with root-mean-square deviations of 1.2-1.4 Å. The ensembles can be converted to each other by performing short MD simulations with the new method, but the convergence is slow, showing mean absolute differences in the calculated energies of 6-7 kJ mol(-1) after 2 ps simulations. Minimisations show even slower convergence and there are strong indications that the energies obtained from minimised structures are different from those obtained by MD.

  8. Exposing Racial Discrimination: Implicit & Explicit Measures–The My Body, My Story Study of 1005 US-Born Black & White Community Health Center Members

    PubMed Central

    Krieger, Nancy; Waterman, Pamela D.; Kosheleva, Anna; Chen, Jarvis T.; Carney, Dana R.; Smith, Kevin W.; Bennett, Gary G.; Williams, David R.; Freeman, Elmer; Russell, Beverley; Thornhill, Gisele; Mikolowsky, Kristin; Rifkin, Rachel; Samuel, Latrice

    2011-01-01

    Background To date, research on racial discrimination and health typically has employed explicit self-report measures, despite their potentially being affected by what people are able and willing to say. We accordingly employed an Implicit Association Test (IAT) for racial discrimination, first developed and used in two recent published studies, and measured associations of the explicit and implicit discrimination measures with each other, socioeconomic and psychosocial variables, and smoking. Methodology/Principal Findings Among the 504 black and 501 white US-born participants, age 35–64, randomly recruited in 2008–2010 from 4 community health centers in Boston, MA, black participants were over 1.5 times more likely (p<0.05) to be worse off economically (e.g., for poverty and low education) and have higher social desirability scores (43.8 vs. 28.2); their explicit discrimination exposure was also 2.5 to 3.7 times higher (p<0.05) depending on the measure used, with over 60% reporting exposure in 3 or more domains and within the last year. Higher IAT scores for target vs. perpetrator of discrimination occurred for the black versus white participants: for “black person vs. white person”: 0.26 vs. 0.13; and for “me vs. them”: 0.24 vs. 0.19. In both groups, only low non-significant correlations existed between the implicit and explicit discrimination measures; social desirability was significantly associated with the explicit but not implicit measures. Although neither the explicit nor implicit discrimination measures were associated with odds of being a current smoker, the excess risk for black participants (controlling for age and gender) rose in models that also controlled for the racial discrimination and psychosocial variables; additional control for socioeconomic position sharply reduced and rendered the association null. Conclusions Implicit and explicit measures of racial discrimination are not equivalent and both warrant use in research on racial discrimination and health, along with data on socioeconomic position and social desirability. PMID:22125618

  9. Postprocessing of docked protein-ligand complexes using implicit solvation models.

    PubMed

    Lindström, Anton; Edvinsson, Lotta; Johansson, Andreas; Andersson, C David; Andersson, Ida E; Raubacher, Florian; Linusson, Anna

    2011-02-28

    Molecular docking plays an important role in drug discovery as a tool for the structure-based design of small organic ligands for macromolecules. Possible applications of docking are identification of the bioactive conformation of a protein-ligand complex and the ranking of different ligands with respect to their strength of binding to a particular target. We have investigated the effect of implicit water on the postprocessing of binding poses generated by molecular docking using MM-PB/GB-SA (molecular mechanics Poisson-Boltzmann and generalized Born surface area) methodology. The investigation was divided into three parts: geometry optimization, pose selection, and estimation of the relative binding energies of docked protein-ligand complexes. Appropriate geometry optimization afforded more accurate binding poses for 20% of the complexes investigated. The time required for this step was greatly reduced by minimizing the energy of the binding site using GB solvation models rather than minimizing the entire complex using the PB model. By optimizing the geometries of docking poses using the GB(HCT+SA) model then calculating their free energies of binding using the PB implicit solvent model, binding poses similar to those observed in crystal structures were obtained. Rescoring of these poses according to their calculated binding energies resulted in improved correlations with experimental binding data. These correlations could be further improved by applying the postprocessing to several of the most highly ranked poses rather than focusing exclusively on the top-scored pose. The postprocessing protocol was successfully applied to the analysis of a set of Factor Xa inhibitors and a set of glycopeptide ligands for the class II major histocompatibility complex (MHC) A(q) protein. These results indicate that the protocol for the postprocessing of docked protein-ligand complexes developed in this paper may be generally useful for structure-based design in drug discovery.

  10. The Role of Generalized Explicit and Implicit Guilt and Shame in Interpersonal Traumatization and Posttraumatic Stress Disorder.

    PubMed

    Bockers, Estelle; Roepke, Stefan; Michael, Lars; Renneberg, Babette; Knaevelsrud, Christine

    2016-02-01

    Posttraumatic stress disorder (PTSD) and interpersonal traumatization are frequently associated with trauma-related guilt and shame. However, research on generalized guilt and shame in PTSD is lacking. The aim of this study was to investigate generalized explicit and implicit guilt and shame in interpersonal traumatization and PTSD. Interpersonally traumatized women either with PTSD (n = 28) or without PTSD (n = 32) and 32 nontraumatized women completed the Test of Self-Conscious Affect-3 and the Implicit Association Test to measure explicit and implicit guilt and shame. Explicit guilt and shame were significantly higher in women with PTSD than in traumatized women without PTSD. Traumatized women without PTSD showed significantly higher levels of explicit guilt and shame than nontraumatized women did. PTSD was associated with implicit guilt but not implicit shame. In addition to trauma-related guilt and shame, generalized explicit guilt and shame and implicit guilt seem to play a crucial role in PTSD.

  11. Grid-Based Surface Generalized Born Model for Calculation of Electrostatic Binding Free Energies.

    PubMed

    Forouzesh, Negin; Izadi, Saeed; Onufriev, Alexey V

    2017-10-23

    Fast and accurate calculation of solvation free energies is central to many applications, such as rational drug design. In this study, we present a grid-based molecular surface implementation of "R6" flavor of the generalized Born (GB) implicit solvent model, named GBNSR6. The speed, accuracy relative to numerical Poisson-Boltzmann treatment, and sensitivity to grid surface parameters are tested on a set of 15 small protein-ligand complexes and a set of biomolecules in the range of 268 to 25099 atoms. Our results demonstrate that the proposed model provides a relatively successful compromise between the speed and accuracy of computing polar components of the solvation free energies (ΔG pol ) and binding free energies (ΔΔG pol ). The model tolerates a relatively coarse grid size h = 0.5 Å, where the grid artifact error in computing ΔΔG pol remains in the range of k B T ∼ 0.6 kcal/mol. The estimated ΔΔG pol s are well correlated (r 2 = 0.97) with the numerical Poisson-Boltzmann reference, while showing virtually no systematic bias and RMSE = 1.43 kcal/mol. The grid-based GBNSR6 model is available in Amber (AmberTools) package of molecular simulation programs.

  12. Attention and Implicit Memory in the Category-Verification and Lexical Decision Tasks

    ERIC Educational Resources Information Center

    Mulligan, Neil W.; Peterson, Daniel

    2008-01-01

    Prior research on implicit memory appeared to support 3 generalizations: Conceptual tests are affected by divided attention, perceptual tasks are affected by certain divided-attention manipulations, and all types of priming are affected by selective attention. These generalizations are challenged in experiments using the implicit tests of category…

  13. Chinese Students' Implicit Theories of Intelligence and Other Personal Attributes: Cross-Domain Generality and Age-Related Differences.

    ERIC Educational Resources Information Center

    Cheng, Zi-Juan; Hau, Kit-Tai; Wen, Jian-Bing; Kong, Chit-Kwong

    Using structural equation modeling (SEM), researchers examined whether there was a general dominating factor that governed students' implicit theories of intelligence, morality, personality, creativity, and social intelligence. The possible age-related changes of students' implicit theories were also studied. In all, 1,650 elementary and junior…

  14. Implicit Kalman filtering

    NASA Technical Reports Server (NTRS)

    Skliar, M.; Ramirez, W. F.

    1997-01-01

    For an implicitly defined discrete system, a new algorithm for Kalman filtering is developed and an efficient numerical implementation scheme is proposed. Unlike the traditional explicit approach, the implicit filter can be readily applied to ill-conditioned systems and allows for generalization to descriptor systems. The implementation of the implicit filter depends on the solution of the congruence matrix equation (A1)(Px)(AT1) = Py. We develop a general iterative method for the solution of this equation, and prove necessary and sufficient conditions for convergence. It is shown that when the system matrices of an implicit system are sparse, the implicit Kalman filter requires significantly less computer time and storage to implement as compared to the traditional explicit Kalman filter. Simulation results are presented to illustrate and substantiate the theoretical developments.

  15. Interfacial folding and membrane insertion of designed peptides studied by molecular dynamics simulations

    PubMed Central

    Im, Wonpil; Brooks, Charles L.

    2005-01-01

    The mechanism of interfacial folding and membrane insertion of designed peptides is explored by using an implicit membrane generalized Born model and replica-exchange molecular dynamics. Folding/insertion simulations initiated from fully extended peptide conformations in the aqueous phase, at least 28 Å away from the membrane interface, demonstrate a general mechanism for structure formation and insertion (when it occurs). The predominately hydrophobic peptides from the synthetic WALP and TMX series first become localized at the membrane-solvent interface where they form significant helical secondary structure via a helix–turn–helix motif that inserts the central hydrophobic residues into the membrane interior, and then fluctuations occur that provide a persistent helical structure throughout the peptide and it inserts with its N-terminal end moving across the membrane. More specifically, we observed that: (i) the WALP peptides (WALP16, WALP19, and WALP23) spontaneously insert in the membrane as just noted; (ii) TMX-1 also inserts spontaneously after a similar mechanism and forms a transmembrane helix with a population of ≈50% at 300 K; and (iii) TMX-3 does not insert, but exists in a fluctuating membrane interface-bound form. These findings are in excellent agreement with available experimental data and demonstrate the potential for new implicit solvent/membrane models together with advanced simulation protocols to guide experimental programs in exploring the nature and mechanism of membrane-associated folding and insertion of biologically important peptides. PMID:15860587

  16. Free energy landscape of protein folding in water: explicit vs. implicit solvent.

    PubMed

    Zhou, Ruhong

    2003-11-01

    The Generalized Born (GB) continuum solvent model is arguably the most widely used implicit solvent model in protein folding and protein structure prediction simulations; however, it still remains an open question on how well the model behaves in these large-scale simulations. The current study uses the beta-hairpin from C-terminus of protein G as an example to explore the folding free energy landscape with various GB models, and the results are compared to the explicit solvent simulations and experiments. All free energy landscapes are obtained from extensive conformation space sampling with a highly parallel replica exchange method. Because solvation model parameters are strongly coupled with force fields, five different force field/solvation model combinations are examined and compared in this study, namely the explicit solvent model: OPLSAA/SPC model, and the implicit solvent models: OPLSAA/SGB (Surface GB), AMBER94/GBSA (GB with Solvent Accessible Surface Area), AMBER96/GBSA, and AMBER99/GBSA. Surprisingly, we find that the free energy landscapes from implicit solvent models are quite different from that of the explicit solvent model. Except for AMBER96/GBSA, all other implicit solvent models find the lowest free energy state not the native state. All implicit solvent models show erroneous salt-bridge effects between charged residues, particularly in OPLSAA/SGB model, where the overly strong salt-bridge effect results in an overweighting of a non-native structure with one hydrophobic residue F52 expelled from the hydrophobic core in order to make better salt bridges. On the other hand, both AMBER94/GBSA and AMBER99/GBSA models turn the beta-hairpin in to an alpha-helix, and the alpha-helical content is much higher than the previously reported alpha-helices in an explicit solvent simulation with AMBER94 (AMBER94/TIP3P). Only AMBER96/GBSA shows a reasonable free energy landscape with the lowest free energy structure the native one despite an erroneous salt-bridge between D47 and K50. Detailed results on free energy contour maps, lowest free energy structures, distribution of native contacts, alpha-helical content during the folding process, NOE comparison with NMR, and temperature dependences are reported and discussed for all five models. Copyright 2003 Wiley-Liss, Inc.

  17. Refinement of NMR structures using implicit solvent and advanced sampling techniques.

    PubMed

    Chen, Jianhan; Im, Wonpil; Brooks, Charles L

    2004-12-15

    NMR biomolecular structure calculations exploit simulated annealing methods for conformational sampling and require a relatively high level of redundancy in the experimental restraints to determine quality three-dimensional structures. Recent advances in generalized Born (GB) implicit solvent models should make it possible to combine information from both experimental measurements and accurate empirical force fields to improve the quality of NMR-derived structures. In this paper, we study the influence of implicit solvent on the refinement of protein NMR structures and identify an optimal protocol of utilizing these improved force fields. To do so, we carry out structure refinement experiments for model proteins with published NMR structures using full NMR restraints and subsets of them. We also investigate the application of advanced sampling techniques to NMR structure refinement. Similar to the observations of Xia et al. (J.Biomol. NMR 2002, 22, 317-331), we find that the impact of implicit solvent is rather small when there is a sufficient number of experimental restraints (such as in the final stage of NMR structure determination), whether implicit solvent is used throughout the calculation or only in the final refinement step. The application of advanced sampling techniques also seems to have minimal impact in this case. However, when the experimental data are limited, we demonstrate that refinement with implicit solvent can substantially improve the quality of the structures. In particular, when combined with an advanced sampling technique, the replica exchange (REX) method, near-native structures can be rapidly moved toward the native basin. The REX method provides both enhanced sampling and automatic selection of the most native-like (lowest energy) structures. An optimal protocol based on our studies first generates an ensemble of initial structures that maximally satisfy the available experimental data with conventional NMR software using a simplified force field and then refines these structures with implicit solvent using the REX method. We systematically examine the reliability and efficacy of this protocol using four proteins of various sizes ranging from the 56-residue B1 domain of Streptococcal protein G to the 370-residue Maltose-binding protein. Significant improvement in the structures was observed in all cases when refinement was based on low-redundancy restraint data. The proposed protocol is anticipated to be particularly useful in early stages of NMR structure determination where a reliable estimate of the native fold from limited data can significantly expedite the overall process. This refinement procedure is also expected to be useful when redundant experimental data are not readily available, such as for large multidomain biomolecules and in solid-state NMR structure determination.

  18. Evaluating the care of general medicine inpatients: how good is implicit review?

    PubMed

    Hayward, R A; McMahon, L F; Bernard, A M

    1993-04-01

    Peer review often consists of implicit evaluations by physician reviewers of the quality and appropriateness of care. This study evaluated the ability of implicit review to measure reliably various aspects of care on a general medicine inpatient service. Retrospective review of patients' charts, using structured implicit review, of a stratified random sample of consecutive admissions to a general medicine ward. A university teaching hospital. Twelve internists were trained in structured implicit review and reviewed 675 patient admissions (with 20% duplicate reviews for a total of 846 reviews). Although inter-rater reliabilities for assessments of overall quality of care and preventable deaths (kappa = 0.5) were adequate for aggregate comparisons (for example, comparing mean ratings on two hospital wards), they were inadequate for reliable evaluations of single patients using one or two reviewers. Reviewers' agreement about most focused quality problems (for example, timeliness of diagnostic evaluation and clinical readiness at time of discharge) and about the appropriateness of hospital ancillary resource use was poor (kappa < or = 0.2). For most focused implicit measures, bias due to specific reviewers who were systematically more harsh or lenient (particularly for evaluation of resource-use appropriateness) accounted for much of the variation in reviewers' assessments, but this was not a substantial problem for the measure of overall quality. Reviewers rarely reported being unable to evaluate the quality of care because of deficiencies in documentation in the patient's chart. For assessment of overall quality and preventable deaths of general medicine inpatients, implicit review by peers had moderate degrees of reliability, but for most other specific aspects of care, physician reviewers could not agree. Implicit review was particularly unreliable at evaluating the appropriateness of hospital resource use and the patient's readiness for discharge, two areas where this type of review is often used.

  19. Atomistic details of the disordered states of KID and pKID. Implications in coupled binding and folding.

    PubMed

    Ganguly, Debabani; Chen, Jianhan

    2009-04-15

    Intrinsically disordered proteins (IDPs) are a newly recognized class of functional proteins for which a lack of stable tertiary fold is required for function. Because of the heterogeneous and dynamical nature, molecular modeling is necessary to provide the missing details of disordered states of IDP that are crucial for understanding their functions. In particular, generalized Born (GB) implicit solvent, combined with replica exchange (REX), might offer an optimal balance between accuracy and efficiency for modeling IDPs. We carried out extensive REX simulations in an optimized GB force field to characterize the disordered states of a regulatory IDP, KID domain of transcription factor CREB, and its phosphorylated form, pKID. The results revealed that both KID and pKID, though highly disordered on the tertiary level, are compact and mainly occupy a small number of helical substates. Interestingly, although phosphorylation of KID Ser133 leads only to marginal changes in average helicities on the ensemble level, underlying conformational substates differ significantly. In particular, pSer133 appears to restrict the accessible conformational space of the loop region and thus reduces the entropic cost of KID folding upon binding to the KIX domain of CREB-binding protein. Such an expanded role of phosphorylation in the KID:KIX recognition was not previously recognized because of a lack of substantial conformational changes on the ensemble level and inaccessibility of the structural details from experiments. The results also suggest that an implicit solvent-based modeling framework, despite various existing limitations, might be feasible for accurate atomistic simulation of small IDPs in general.

  20. Do People Use Their Implicit Theories of Creativity as General Theories?

    ERIC Educational Resources Information Center

    Lee, Hong; Kim, Jungsik; Ryu, Yeonjae; Song, Seokjong

    2015-01-01

    This study examines whether people use the general implicit theories of creativity or not when applying them to themselves and others. On the basis of the actor-observer asymmetry theory, the authors propose that conception of creativity would be differently constructed depending on the targets of attention: general, self, and other. Three studies…

  1. A simple method for the fast calculation of charge redistribution of solutes in an implicit solvent model

    NASA Astrophysics Data System (ADS)

    Dias, L. G.; Shimizu, K.; Farah, J. P. S.; Chaimovich, H.

    2002-09-01

    We propose and demonstrate the usefulness of a method, defined as generalized Born electronegativity equalization method (GBEEM) to estimate solvent-induced charge redistribution. The charges obtained by GBEEM, in a representative series of small organic molecules, were compared to PM3-CM1 charges in vacuum and in water. Linear regressions with appropriate correlation coefficients and standard deviations between GBEEM and PM3-CM1 methods were obtained ( R=0.94,SD=0.15, Ftest=234, N=32, in vacuum; R=0.94,SD=0.16, Ftest=218, N=29, in water). In order to test the GBEEM response when intermolecular interactions are involved we calculated a water dimer in dielectric water using both GBEEM and PM3-CM1 and the results were similar. Hence, the method developed here is comparable to established calculation methods.

  2. I like myself but I don't know why: enhancing implicit self-esteem by subliminal evaluative conditioning.

    PubMed

    Dijksterhuis, Ap

    2004-02-01

    On the basis of a conceptualization of implicit self-esteem as the implicit attitude toward the self, it was predicted that implicit self-esteem could be enhanced by subliminal evaluative conditioning. In 5 experiments, participants were repeatedly presented with trials in which the word I was paired with positive trait terms. Relative to control conditions, this procedure enhanced implicit self-esteem. The effects generalized across 3 measures of implicit self-esteem (Experiments 1-3). Furthermore, evaluative conditioning enhanced implicit self-esteem among people with low-temporal implicit self-esteem and among people with high-temporal implicit self-esteem (Experiment 4). In addition, it was shown that conditioning enhanced self-esteem to such an extent that it made participants insensitive to negative intelligence feedback (Experiments 5a and 5b). Various implications are discussed.

  3. A comparison of physician implicit racial bias towards adults versus children

    PubMed Central

    Johnson, Tiffani J.; Winger, Daniel G.; Hickey, Robert W.; Switzer, Galen E.; Miller, Elizabeth; Nguyen, Margaret B.; Saladino, Richard A.; Hausmann, Leslie R. M.

    2016-01-01

    Background and Objectives The general population and most physicians have implicit racial bias against black adults. Pediatricians also have implicit bias against black adults, albeit less than other specialties. There is no published research on the implicit racial attitudes of pediatricians or other physicians towards children. Our objectives were to compare implicit racial bias towards adults versus children among resident physicians working in a pediatric emergency department (ED), and to assess whether bias varied by specialty (pediatrics, emergency medicine, or other), gender, race, age, and year of training. Methods We measured implicit racial bias of residents before a pediatric ED shift using the Adult and Child Race Implicit Association Tests (IATs). Generalized linear models compared Adult and Child IAT scores and determined the association of participant demographics with Adult and Child IAT scores. Results Among 91 residents, we found moderate pro-white/anti-black bias on both the Adult (M=0.49, SD=0.34) and Child Race IAT (M=0.55, SD=0.37). There was no significant difference between Adult and Child Race IAT scores (difference=0.06, p=0.15). Implicit bias was not associated with resident demographic characteristics, including specialty. Conclusions This is the first study demonstrating that resident physicians have implicit racial bias against black children, similar to levels of bias against black adults. Bias in our study did not vary by resident demographic characteristics, including specialty, suggesting that pediatric residents are as susceptible as other physicians to implicit bias. Future studies are needed to explore how physicians’ implicit attitudes towards parents and children may impact inequities in pediatric healthcare. PMID:27620844

  4. Background-Error Correlation Model Based on the Implicit Solution of a Diffusion Equation

    DTIC Science & Technology

    2010-01-01

    1 Background- Error Correlation Model Based on the Implicit Solution of a Diffusion Equation Matthew J. Carrier* and Hans Ngodock...4. TITLE AND SUBTITLE Background- Error Correlation Model Based on the Implicit Solution of a Diffusion Equation 5a. CONTRACT NUMBER 5b. GRANT...2001), which sought to model error correlations based on the explicit solution of a generalized diffusion equation. The implicit solution is

  5. Awareness of Implicit Attitudes

    PubMed Central

    Hahn, Adam; Judd, Charles M.; Hirsh, Holen K.; Blair, Irene V.

    2013-01-01

    Research on implicit attitudes has raised questions about how well people know their own attitudes. Most research on this question has focused on the correspondence between measures of implicit attitudes and measures of explicit attitudes, with low correspondence interpreted as showing that people have little awareness of their implicit attitudes. We took a different approach and directly asked participants to predict their results on upcoming IAT measures of implicit attitudes toward five different social groups. We found that participants were surprisingly accurate in their predictions. Across four studies, predictions were accurate regardless of whether implicit attitudes were described as true attitudes or culturally learned associations (Studies 1 and 2), regardless of whether predictions were made as specific response patterns (Study 1) or as conceptual responses (Studies 2–4), and regardless of how much experience or explanation participants received before making their predictions (Study 4). Study 3 further suggested that participants’ predictions reflected unique insight into their own implicit responses, beyond intuitions about how people in general might respond. Prediction accuracy occurred despite generally low correspondence between implicit and explicit measures of attitudes, as found in prior research. All together, the research findings cast doubt on the belief that attitudes or evaluations measured by the IAT necessarily reflect unconscious attitudes. PMID:24294868

  6. Attitudes toward Overweight Individuals among Fitness Center Employees: An Examination of Contextual Effects

    ERIC Educational Resources Information Center

    Dimmock, James A.; Hallett, Bree E.; Grove, J. Robert

    2009-01-01

    Our study assessed implicit and explicit evaluations of overweight individuals among a sample of fitness center employees (N = 70). Participants completed a general demographics questionnaire and an explicit, self-report Antifat Attitudes Test (AFAT). Participants also completed two Implicit Association Tests (IATs) to measure implicit attitudes…

  7. Young Adults' Implicit and Explicit Attitudes towards the Sexuality of Older Adults.

    PubMed

    Thompson, Ashley E; O'Sullivan, Lucia F; Byers, E Sandra; Shaughnessy, Krystelle

    2014-09-01

    Sexual interest and capacity can extend far into later life and result in many positive health outcomes. Yet there is little support for sexual expression in later life, particularly among young adults. This study assessed and compared young adults' explicit and implicit attitudes towards older adult sexuality. A sample of 120 participants (18-24 years; 58% female) completed a self-report (explicit) measure and a series of Implicit Association Tests capturing attitudes towards sexuality among older adults. Despite reporting positive explicit attitudes, young people revealed an implicit bias against the sexual lives of older adults. In particular, young adults demonstrated implicit biases favouring general, as compared to sexual, activities and young adults as compared to older adults. Moreover, the bias favouring general activities was amplified with regard to older adults as compared to younger adults. Our findings challenge the validity of research relying on self-reports of attitudes about older adult sexuality.

  8. Implicit sequence-specific motor learning after sub-cortical stroke is associated with increased prefrontal brain activations: An fMRI study

    PubMed Central

    Meehan, Sean K.; Randhawa, Bubblepreet; Wessel, Brenda; Boyd, Lara A.

    2010-01-01

    Implicit motor learning is preserved after stroke, but how the brain compensates for damage to facilitate learning is unclear. We used a random effects analysis to determine how stroke alters patterns of brain activity during implicit sequence-specific motor learning as compared to general improvements in motor control. Nine healthy participants and 9 individuals with chronic, right focal sub-cortical stroke performed a continuous joystick-based tracking task during an initial fMRI session, over 5 days of practice, and a retention test during a separate fMRI session. Sequence-specific implicit motor learning was differentiated from general improvements in motor control by comparing tracking performance on a novel, repeated tracking sequences during early practice and again at the retention test. Both groups demonstrated implicit sequence-specific motor learning at the retention test, yet substantial differences were apparent. At retention, healthy control participants demonstrated increased BOLD response in left dorsal premotor cortex (BA 6) but decreased BOLD response left dorsolateral prefrontal cortex (DLPFC; BA 9) during repeated sequence tracking. In contrast, at retention individuals with stroke did not show this reduction in DLPFC during repeated tracking. Instead implicit sequence-specific motor learning and general improvements in motor control were associated with increased BOLD response in the left middle frontal gyrus BA 8, regardless of sequence type after stroke. These data emphasize the potential importance of a prefrontal-based attentional network for implicit motor learning after stroke. The present study is the first to highlight the importance of the prefrontal cortex for implicit sequence-specific motor learning after stroke. PMID:20725908

  9. Comparison of Physician Implicit Racial Bias Toward Adults Versus Children.

    PubMed

    Johnson, Tiffani J; Winger, Daniel G; Hickey, Robert W; Switzer, Galen E; Miller, Elizabeth; Nguyen, Margaret B; Saladino, Richard A; Hausmann, Leslie R M

    2017-03-01

    The general population and most physicians have implicit racial bias against black adults. Pediatricians also have implicit bias against black adults, albeit less than other specialties. There is no published research on the implicit racial attitudes of pediatricians or other physicians toward children. Our objectives were to compare implicit racial bias toward adults versus children among resident physicians working in a pediatric emergency department, and to assess whether bias varied by specialty (pediatrics, emergency medicine, or other), gender, race, age, and year of training. We measured implicit racial bias of residents before a pediatric emergency department shift using the Adult and Child Race Implicit Association Tests (IATs). Generalized linear models compared Adult and Child IAT scores and determined the association of participant demographics with Adult and Child IAT scores. Among 91 residents, we found moderate pro-white/anti-black bias on both the Adult (mean = 0.49, standard deviation = 0.34) and Child Race IAT (mean = 0.55, standard deviation = 0.37). There was no significant difference between Adult and Child Race IAT scores (difference = 0.06, P = .15). Implicit bias was not associated with resident demographic characteristics, including specialty. This is the first study demonstrating that resident physicians have implicit racial bias against black children, similar to levels of bias against black adults. Bias in our study did not vary by resident demographic characteristics, including specialty, suggesting that pediatric residents are as susceptible as other physicians to implicit bias. Future studies are needed to explore how physicians' implicit attitudes toward parents and children may impact inequities in pediatric health care. Copyright © 2016 Academic Pediatric Association. All rights reserved.

  10. Proposed Test of Relative Phase as Hidden Variable in Quantum Mechanics

    DTIC Science & Technology

    2012-01-01

    implicitly due to its ubiquity in quantum theory , but searches for dependence of measurement outcome on other parameters have been lacking. For a two -state...implemen- tation for the specific case of an atomic two -state system with laser-induced fluores- cence for measurement. Keywords Quantum measurement...Measurement postulate · Born rule 1 Introduction 1.1 Problems with Quantum Measurement Quantum theory prescribes probabilities for outcomes of measurements

  11. Modelling short pulse, high intensity laser plasma interactions

    NASA Astrophysics Data System (ADS)

    Evans, R. G.

    2006-06-01

    Modelling the interaction of ultra-intense laser pulses with solid targets is made difficult through the large range of length and time scales involved in the transport of relativistic electrons. An implicit hybrid PIC-fluid model using the commercial code LSP (LSP is marketed by MRC (Albuquerque), New Mexico, USA) reveals a variety of complex phenomena which seem to be borne out in experiments and some existing theories.

  12. Explicit Pre-Training Instruction Does Not Improve Implicit Perceptual-Motor Sequence Learning

    ERIC Educational Resources Information Center

    Sanchez, Daniel J.; Reber, Paul J.

    2013-01-01

    Memory systems theory argues for separate neural systems supporting implicit and explicit memory in the human brain. Neuropsychological studies support this dissociation, but empirical studies of cognitively healthy participants generally observe that both kinds of memory are acquired to at least some extent, even in implicit learning tasks. A key…

  13. Beyond IQ: A Latent State-Trait Analysis of General Intelligence, Dynamic Decision Making, and Implicit Learning

    ERIC Educational Resources Information Center

    Danner, Daniel; Hagemann, Dirk; Schankin, Andrea; Hager, Marieke; Funke, Joachim

    2011-01-01

    The present study investigated cognitive performance measures beyond IQ. In particular, we investigated the psychometric properties of dynamic decision making variables and implicit learning variables and their relation with general intelligence and professional success. N = 173 employees from different companies and occupational groups completed…

  14. The self-protective nature of implicit identity and its relationship to weight bias and short-term weight loss.

    PubMed

    Carels, Robert A; Hinman, Nova; Koball, Afton; Oehlhof, Marissa Wagner; Gumble, Amanda; Young, Kathleen M

    2011-01-01

    Research suggests that making overly positive self-evaluations is the norm rather than the exception. However, unlike other stigmatized groups, overweight individuals do not exhibit a positive in-group social identity and instead exhibit significant explicit, implicit, and internalized weight bias. Therefore, it is not known whether overweight/obese individuals will evidence self-enhancement on general traits (good, attractive), or on traits inconsistent with fat stereotypes (disciplined, active, healthy eater), on an assessment of implicit attitudes. Similarly, it is not known whether these ratings will be associated with preexisting levels of weight bias, gender, or short-term weight loss. At baseline, 53 overweight/obese adults (BMI > 27 kg/m(2), mean BMI = 37.3 kg/m(2), SD = 6.6 kg/m(2), 89% Caucasian, and 77% female) participating in a weight loss intervention completed measures of explicit and internalized weight bias as well as implicit weight bias and identity (self-other comparisons). Although participants evidenced significant anti-fat attitudes, they implicitly identified themselves as significantly thinner, better, more attractive, active, disciplined, and more likely to eat healthy than 'other' people. Compared to men, women were less likely to view themselves as thin and attractive relative to others. Greater implicit anti-fat bias and implicitly seeing the self as thin relative to others was associated with less short-term weight loss. Despite evidence for explicit, implicit, and internalized weight bias, participants generally evidenced a positive implicit self-identity, including areas consistent with negative fat stereotypes. Copyright © 2011 S. Karger AG, Basel.

  15. Sensitivity analysis for parametric generalized implicit quasi-variational-like inclusions involving P-[eta]-accretive mappings

    NASA Astrophysics Data System (ADS)

    Kazmi, K. R.; Khan, F. A.

    2008-01-01

    In this paper, using proximal-point mapping technique of P-[eta]-accretive mapping and the property of the fixed-point set of set-valued contractive mappings, we study the behavior and sensitivity analysis of the solution set of a parametric generalized implicit quasi-variational-like inclusion involving P-[eta]-accretive mapping in real uniformly smooth Banach space. Further, under suitable conditions, we discuss the Lipschitz continuity of the solution set with respect to the parameter. The technique and results presented in this paper can be viewed as extension of the techniques and corresponding results given in [R.P. Agarwal, Y.-J. Cho, N.-J. Huang, Sensitivity analysis for strongly nonlinear quasi-variational inclusions, Appl. MathE Lett. 13 (2002) 19-24; S. Dafermos, Sensitivity analysis in variational inequalities, Math. Oper. Res. 13 (1988) 421-434; X.-P. Ding, Sensitivity analysis for generalized nonlinear implicit quasi-variational inclusions, Appl. Math. Lett. 17 (2) (2004) 225-235; X.-P. Ding, Parametric completely generalized mixed implicit quasi-variational inclusions involving h-maximal monotone mappings, J. Comput. Appl. Math. 182 (2) (2005) 252-269; X.-P. Ding, C.L. Luo, On parametric generalized quasi-variational inequalities, J. Optim. Theory Appl. 100 (1999) 195-205; Z. Liu, L. Debnath, S.M. Kang, J.S. Ume, Sensitivity analysis for parametric completely generalized nonlinear implicit quasi-variational inclusions, J. Math. Anal. Appl. 277 (1) (2003) 142-154; R.N. Mukherjee, H.L. Verma, Sensitivity analysis of generalized variational inequalities, J. Math. Anal. Appl. 167 (1992) 299-304; M.A. Noor, Sensitivity analysis framework for general quasi-variational inclusions, Comput. Math. Appl. 44 (2002) 1175-1181; M.A. Noor, Sensitivity analysis for quasivariational inclusions, J. Math. Anal. Appl. 236 (1999) 290-299; J.Y. Park, J.U. Jeong, Parametric generalized mixed variational inequalities, Appl. Math. Lett. 17 (2004) 43-48].

  16. The neural basis of implicit learning and memory: a review of neuropsychological and neuroimaging research.

    PubMed

    Reber, Paul J

    2013-08-01

    Memory systems research has typically described the different types of long-term memory in the brain as either declarative versus non-declarative or implicit versus explicit. These descriptions reflect the difference between declarative, conscious, and explicit memory that is dependent on the medial temporal lobe (MTL) memory system, and all other expressions of learning and memory. The other type of memory is generally defined by an absence: either the lack of dependence on the MTL memory system (nondeclarative) or the lack of conscious awareness of the information acquired (implicit). However, definition by absence is inherently underspecified and leaves open questions of how this type of memory operates, its neural basis, and how it differs from explicit, declarative memory. Drawing on a variety of studies of implicit learning that have attempted to identify the neural correlates of implicit learning using functional neuroimaging and neuropsychology, a theory of implicit memory is presented that describes it as a form of general plasticity within processing networks that adaptively improve function via experience. Under this model, implicit memory will not appear as a single, coherent, alternative memory system but will instead be manifested as a principle of improvement from experience based on widespread mechanisms of cortical plasticity. The implications of this characterization for understanding the role of implicit learning in complex cognitive processes and the effects of interactions between types of memory will be discussed for examples within and outside the psychology laboratory. Copyright © 2013 Elsevier Ltd. All rights reserved.

  17. Multi-agent systems in epidemiology: a first step for computational biology in the study of vector-borne disease transmission.

    PubMed

    Roche, Benjamin; Guégan, Jean-François; Bousquet, François

    2008-10-15

    Computational biology is often associated with genetic or genomic studies only. However, thanks to the increase of computational resources, computational models are appreciated as useful tools in many other scientific fields. Such modeling systems are particularly relevant for the study of complex systems, like the epidemiology of emerging infectious diseases. So far, mathematical models remain the main tool for the epidemiological and ecological analysis of infectious diseases, with SIR models could be seen as an implicit standard in epidemiology. Unfortunately, these models are based on differential equations and, therefore, can become very rapidly unmanageable due to the too many parameters which need to be taken into consideration. For instance, in the case of zoonotic and vector-borne diseases in wildlife many different potential host species could be involved in the life-cycle of disease transmission, and SIR models might not be the most suitable tool to truly capture the overall disease circulation within that environment. This limitation underlines the necessity to develop a standard spatial model that can cope with the transmission of disease in realistic ecosystems. Computational biology may prove to be flexible enough to take into account the natural complexity observed in both natural and man-made ecosystems. In this paper, we propose a new computational model to study the transmission of infectious diseases in a spatially explicit context. We developed a multi-agent system model for vector-borne disease transmission in a realistic spatial environment. Here we describe in detail the general behavior of this model that we hope will become a standard reference for the study of vector-borne disease transmission in wildlife. To conclude, we show how this simple model could be easily adapted and modified to be used as a common framework for further research developments in this field.

  18. The adoption of physical activity and eating behaviors among persons with obesity and in the general population: the role of implicit attitudes within the Theory of Planned Behavior.

    PubMed

    Chevance, Guillaume; Caudroit, Johan; Romain, Ahmed J; Boiché, Julie

    2017-03-01

    Obesity can be prevented by the combined adoption of a regular physical activity (PA) and healthy eating behaviors (EB). Researchers mainly focused on socio-cognitive models, such as the Theory of Planned Behavior (TPB), to identify the psychological antecedents of these behaviors. However, few studies were interested in testing the potential contribution of automatic processes in the prediction of PA and EB. Thus, the main objective of this study was to explore the specific role of implicit attitudes in the pattern of prediction of self-reported PA and EB in the TPB framework, among persons with obesity and in adults from the general population. One hundred and fifty-three adults participated to this cross-sectional study among which 59 obese persons (74% women, age: 50.6 ± 12.3 years, BMI: 36.8 ± 4.03 kg m - ²) and 94 people from the general population (51% women; age: 34.7 ± 8.9 years). Implicit attitudes toward PA and EB were estimated through two Implicit Association Tests. TPB variables, PA and EB were assessed by questionnaire. Regarding to the prediction of PA, a significant contribution of implicit attitudes emerged in obese people, β = .25; 95%[CI: .01, .50]; P = .044, beyond the TPB variables, contrary to participants from the general population. The present study suggests that implicit attitudes play a specific role among persons with obesity regarding PA. Other studies are needed to examine which kind of psychological processes are specifically associated with PA and EB among obese people.

  19. Suboptimal care and maternal mortality among foreign-born women in Sweden: maternal death audit with application of the 'migration three delays' model.

    PubMed

    Esscher, Annika; Binder-Finnema, Pauline; Bødker, Birgit; Högberg, Ulf; Mulic-Lutvica, Ajlana; Essén, Birgitta

    2014-04-12

    Several European countries report differences in risk of maternal mortality between immigrants from low- and middle-income countries and host country women. The present study identified suboptimal factors related to care-seeking, accessibility, and quality of care for maternal deaths that occurred in Sweden from 1988-2010. A subset of maternal death records (n = 75) among foreign-born women from low- and middle-income countries and Swedish-born women were audited using structured implicit review. One case of foreign-born maternal death was matched with two native born Swedish cases of maternal death. An assessment protocol was developed that applied both the 'migration three delays' framework and a modified version of the Confidential Enquiry from the United Kingdom. The main outcomes were major and minor suboptimal factors associated with maternal death in this high-income, low-maternal mortality context. Major and minor suboptimal factors were associated with a majority of maternal deaths and significantly more often to foreign-born women (p = 0.01). The main delays to care-seeking were non-compliance among foreign-born women and communication barriers, such as incongruent language and suboptimal interpreter system or usage. Inadequate care occurred more often among the foreign-born (p = 0.04), whereas delays in consultation/referral and miscommunication between health care providers where equally common between the two groups. Suboptimal care factors, major and minor, were present in more than 2/3 of maternal deaths in this high-income setting. Those related to migration were associated to miscommunication, lack of professional interpreters, and limited knowledge about rare diseases and pregnancy complications. Increased insight into a migration perspective is advocated for maternity clinicians who provide care to foreign-born women.

  20. Implicit cognitive aggression among young male prisoners: Association with dispositional and current aggression.

    PubMed

    Ireland, Jane L; Adams, Christine

    2015-01-01

    The current study explores associations between implicit and explicit aggression in young adult male prisoners, seeking to apply the Reflection-Impulsive Model and indicate parity with elements of the General Aggression Model and social cognition. Implicit cognitive aggressive processing is not an area that has been examined among prisoners. Two hundred and sixty two prisoners completed an implicit cognitive aggression measure (Puzzle Test) and explicit aggression measures, covering current behaviour (DIPC-R) and aggression disposition (AQ). It was predicted that dispositional aggression would be predicted by implicit cognitive aggression, and that implicit cognitive aggression would predict current engagement in aggressive behaviour. It was also predicted that more impulsive implicit cognitive processing would associate with aggressive behaviour whereas cognitively effortful implicit cognitive processing would not. Implicit aggressive cognitive processing was associated with increased dispositional aggression but not current reports of aggressive behaviour. Impulsive implicit cognitive processing of an aggressive nature predicted increased dispositional aggression whereas more cognitively effortful implicit cognitive aggression did not. The article concludes by outlining the importance of accounting for implicit cognitive processing among prisoners and the need to separate such processing into facets (i.e. impulsive vs. cognitively effortful). Implications for future research and practice in this novel area of study are indicated. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Implicit memory. Retention without remembering.

    PubMed

    Roediger, H L

    1990-09-01

    Explicit measures of human memory, such as recall or recognition, reflect conscious recollection of the past. Implicit tests of retention measure transfer (or priming) from past experience on tasks that do not require conscious recollection of recent experiences for their performance. The article reviews research on the relation between explicit and implicit memory. The evidence points to substantial differences between standard explicit and implicit tests, because many variables create dissociations between these tests. For example, although pictures are remembered better than words on explicit tests, words produce more priming than do pictures on several implicit tests. These dissociations may implicate different memory systems that subserve distinct memorial functions, but the present argument is that many dissociations can be understood by appealing to general principles that apply to both explicit and implicit tests. Phenomena studied under the rubric of implicit memory may have important implications in many other fields, including social cognition, problem solving, and cognitive development.

  2. Dendrimer Interactions with Lipid Bilayer: Comparison of Force Field and Effect of Implicit vs Explicit Solvation.

    PubMed

    Kanchi, Subbarao; Gosika, Mounika; Ayappa, K G; Maiti, Prabal K

    2018-06-13

    The understanding of dendrimer interactions with cell membranes has great importance in drug/gene delivery based therapeutics. Although molecular simulations have been used to understand the nature of dendrimer interactions with lipid membranes, its dependency on available force field parameters is poorly understood. In this study, we have carried out fully atomistic molecular dynamics (MD) simulations of a protonated G3 poly(amido amine) (PAMAM) dendrimer-dimyristoylphosphatidylcholine (DMPC) lipid bilayer complex using three different force fields (FFs) namely, CHARMM, GAFF, and GROMOS in the presence of explicit water to understand the structure of the lipid-dendrimer complex and nature of their interaction. CHARMM and GAFF dendrimers initially in contact with the lipid head groups were found to move away from the lipid bilayer during the course of simulation; however, the dendrimer remained strongly bound to the lipid head groups with the GROMOS FF. Potential of the mean force (PMF) computations of the dendrimer along the bilayer normal showed a repulsive barrier (∼20 kcal/mol) between dendrimer and lipid bilayer in the case of CHARMM and GAFF force fields. In contrast, an attractive interaction (∼40 kcal/mol) is obtained with the GROMOS force field, consistent with experimental observations of membrane binding observed with lower generation G3 PAMAM dendrimers. This difference with the GROMOS dendrimer is attributed to the strong dendrimer-lipid interaction and lowered surface hydration of the dendrimer. Assessing the role of solvent, we find that the CHARMM and GAFF dendrimers strongly bind to the lipid bilayer with an implicit solvent (Generalized Born) model, whereas binding is not observed with explicit water (TIP3P). The opposing nature of dendrimer-membrane interactions in the presence of explicit and implicit solvents demonstrates that hydration effects play an important role in modulating the dendrimer-lipid interaction warranting a case for refinement of the existing dendrimer/lipid force fields.

  3. Direct speech quotations promote low relative-clause attachment in silent reading of English.

    PubMed

    Yao, Bo; Scheepers, Christoph

    2018-07-01

    The implicit prosody hypothesis (Fodor, 1998, 2002) proposes that silent reading coincides with a default, implicit form of prosody to facilitate sentence processing. Recent research demonstrated that a more vivid form of implicit prosody is mentally simulated during silent reading of direct speech quotations (e.g., Mary said, "This dress is beautiful"), with neural and behavioural consequences (e.g., Yao, Belin, & Scheepers, 2011; Yao & Scheepers, 2011). Here, we explored the relation between 'default' and 'simulated' implicit prosody in the context of relative-clause (RC) attachment in English. Apart from confirming a general low RC-attachment preference in both production (Experiment 1) and comprehension (Experiments 2 and 3), we found that during written sentence completion (Experiment 1) or when reading silently (Experiment 2), the low RC-attachment preference was reliably enhanced when the critical sentences were embedded in direct speech quotations as compared to indirect speech or narrative sentences. However, when reading aloud (Experiment 3), direct speech did not enhance the general low RC-attachment preference. The results from Experiments 1 and 2 suggest a quantitative boost to implicit prosody (via auditory perceptual simulation) during silent production/comprehension of direct speech. By contrast, when reading aloud (Experiment 3), prosody becomes equally salient across conditions due to its explicit nature; indirect speech and narrative sentences thus become as susceptible to prosody-induced syntactic biases as direct speech. The present findings suggest a shared cognitive basis between default implicit prosody and simulated implicit prosody, providing a new platform for studying the effects of implicit prosody on sentence processing. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. A survey of implicit particle filters for data assimilation [Implicit particle filters for data assimilation

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

    Chorin, Alexandre J.; Morzfeld, Matthias; Tu, Xuemin

    Implicit particle filters for data assimilation update the particles by first choosing probabilities and then looking for particle locations that assume them, guiding the particles one by one to the high probability domain. We provide a detailed description of these filters, with illustrative examples, together with new, more general, methods for solving the algebraic equations and with a new algorithm for parameter identification.

  5. Exposure to graphic warning labels on cigarette packages: Effects on implicit and explicit attitudes towards smoking among young adults.

    PubMed

    Macy, Jonathan T; Chassin, Laurie; Presson, Clark C; Yeung, Ellen

    2016-01-01

    To test the effect of exposure to the US Food and Drug Administration's proposed graphic images with text warning statements for cigarette packages on implicit and explicit attitudes towards smoking. A two-session web-based study was conducted with 2192 young adults 18-25-years-old. During session one, demographics, smoking behaviour, and baseline implicit and explicit attitudes were assessed. Session two, completed on average 18 days later, contained random assignment to viewing one of three sets of cigarette packages, graphic images with text warnings, text warnings only, or current US Surgeon General's text warnings. Participants then completed post-exposure measures of implicit and explicit attitudes. ANCOVAs tested the effect of condition on the outcomes, controlling for baseline attitudes. Smokers who viewed packages with graphic images plus text warnings demonstrated more negative implicit attitudes compared to smokers in the other conditions (p = .004). For the entire sample, explicit attitudes were more negative for those who viewed graphic images plus text warnings compared to those who viewed current US Surgeon General's text warnings (p = .014), but there was no difference compared to those who viewed text-only warnings. Graphic health warnings on cigarette packages can influence young adult smokers' implicit attitudes towards smoking.

  6. Combined AIE/EBE/GMRES approach to incompressible flows. [Adaptive Implicit-Explicit/Grouped Element-by-Element/Generalized Minimum Residuals

    NASA Technical Reports Server (NTRS)

    Liou, J.; Tezduyar, T. E.

    1990-01-01

    Adaptive implicit-explicit (AIE), grouped element-by-element (GEBE), and generalized minimum residuals (GMRES) solution techniques for incompressible flows are combined. In this approach, the GEBE and GMRES iteration methods are employed to solve the equation systems resulting from the implicitly treated elements, and therefore no direct solution effort is involved. The benchmarking results demonstrate that this approach can substantially reduce the CPU time and memory requirements in large-scale flow problems. Although the description of the concepts and the numerical demonstration are based on the incompressible flows, the approach presented here is applicable to larger class of problems in computational mechanics.

  7. Implicit Associations in Social Anxiety Disorder: The Effects of Comorbid Depression

    PubMed Central

    Wong, Judy; Morrison, Amanda S.; Heimberg, Richard G.; Goldin, Philippe R.; Gross, James J.

    2014-01-01

    Implicit associations of the self to concepts like “calm” have been shown to be weaker in persons with social anxiety than in non-anxious healthy controls. However, other implicit self associations, such as those to acceptance or rejection, have been less studied in social anxiety, and none of this work has been conducted with clinical samples. Furthermore, the importance of depression in these relationships has not been well investigated. We addressed these issues by administering two Implicit Association Tests (IATs; Greenwald, McGhee, & Schwartz, 1998), one examining the implicit association of self/other to anxiety/calmness and the other examining the association of self/other to rejection/acceptance, to individuals with generalized social anxiety disorder (SAD, n = 85), individuals with generalized SAD and a current or past diagnosis of major depressive disorder or current dysthymic disorder (n = 47), and non-anxious, non-depressed healthy controls (n = 44). The SAD and SAD-depression groups showed weaker implicit self-calmness associations than healthy controls, with the comorbid group showing the weakest self-calmness associations. The SAD-depression group showed the weakest implicit self-acceptance associations; no difference was found between non-depressed individuals with SAD and healthy controls. Post hoc analyses revealed that differences appeared to be driven by those with current depression. The SAD-only and SAD-depression groups did not differ in self-reported (explicit) social anxiety. The implications of these findings for the understanding of SAD-depression comorbidity and for the treatment of SAD are considered. PMID:24983794

  8. Implicit false-belief processing in the human brain.

    PubMed

    Schneider, Dana; Slaughter, Virginia P; Becker, Stefanie I; Dux, Paul E

    2014-11-01

    Eye-movement patterns in 'Sally-Anne' tasks reflect humans' ability to implicitly process the mental states of others, particularly false-beliefs - a key theory of mind (ToM) operation. It has recently been proposed that an efficient ToM system, which operates in the absence of awareness (implicit ToM, iToM), subserves the analysis of belief-like states. This contrasts to consciously available belief processing, performed by the explicit ToM system (eToM). The frontal, temporal and parietal cortices are engaged when humans explicitly 'mentalize' about others' beliefs. However, the neural underpinnings of implicit false-belief processing and the extent to which they draw on networks involved in explicit general-belief processing are unknown. Here, participants watched 'Sally-Anne' movies while fMRI and eye-tracking measures were acquired simultaneously. Participants displayed eye-movements consistent with implicit false-belief processing. After independently localizing the brain areas involved in explicit general-belief processing, only the left anterior superior temporal sulcus and precuneus revealed greater blood-oxygen-level-dependent activity for false- relative to true-belief trials in our iToM paradigm. No such difference was found for the right temporal-parietal junction despite significant activity in this area. These findings fractionate brain regions that are associated with explicit general ToM reasoning and false-belief processing in the absence of awareness. Copyright © 2014 Elsevier Inc. All rights reserved.

  9. Parallel Tempering of Dark Matter from the Ebola Virus Proteome: Comparison of CHARMM36m and CHARMM22 Force Fields with Implicit Solvent and Coarse Grained Model

    DTIC Science & Technology

    2017-08-10

    simulation models the conformational plasticity along the helix-forming reaction coordinate was limited by free - energy barriers. By comparison the coarse...revealed. The latter becomes evident in comparing the energy Z-score landscapes , where CHARMM22 simulation shows a manifold of shuttling...solvent simulations of calculating the charging free energy of protein conformations.33 Deviation to the protocol by modification of Born radii

  10. Implicit and explicit preferences for physical attractiveness in a romantic partner: a double dissociation in predictive validity.

    PubMed

    Eastwick, Paul W; Eagly, Alice H; Finkel, Eli J; Johnson, Sarah E

    2011-11-01

    Five studies develop and examine the predictive validity of an implicit measure of the preference for physical attractiveness in a romantic partner. Three hypotheses were generally supported. First, 2 variants of the go/no-go association task revealed that participants, on average, demonstrate an implicit preference (i.e., a positive spontaneous affective reaction) for physical attractiveness in a romantic partner. Second, these implicit measures were not redundant with a traditional explicit measure: The correlation between these constructs was .00 on average, and the implicit measures revealed no reliable sex differences, unlike the explicit measure. Third, explicit and implicit measures exhibited a double dissociation in predictive validity. Specifically, explicit preferences predicted the extent to which attractiveness was associated with participants' romantic interest in opposite-sex photographs but not their romantic interest in real-life opposite-sex speed-daters or confederates. Implicit preferences showed the opposite pattern. This research extends prior work on implicit processes in romantic relationships and offers the first demonstration that any measure of a preference for a particular characteristic in a romantic partner (an implicit measure of physical attractiveness, in this case) predicts individuals' evaluation of live potential romantic partners.

  11. Implicit Social Biases in People with Autism

    PubMed Central

    Birmingham, Elina; Stanley, Damian; Nair, Remya; Adolphs, Ralph

    2015-01-01

    Implicit social biases are ubiquitous and are known to influence social behavior. A core diagnostic criterion of Autism Spectrum Disorder (ASD) is abnormal social behavior. Here we investigated the extent to which individuals with ASD might show a specific attenuation of implicit social biases, using the Implicit Association Test (IAT) across Social (gender, race) and Nonsocial (flowers/insect, shoes) categories. High-functioning adults with ASD showed intact but reduced IAT effects relative to healthy controls. Importantly, we observed no selective attenuation of implicit social (vs. nonsocial) biases in our ASD population. To extend these results, we collected data from a large online sample of the general population, and explored correlations between autistic traits and IAT effects. No associations were found between autistic traits and IAT effects for any of the categories tested in our online sample. Taken together, these results suggest that implicit social biases, as measured by the IAT, are largely intact in ASD. PMID:26386014

  12. Disorder in the Representational Warehouse

    ERIC Educational Resources Information Center

    McGeer, Victoria; Schwitzgebel, Eric

    2006-01-01

    Although developmental psychologists are generally happy to endorse dissociations and gradualist views of development like Woolley's (2006), the design and interpretation of developmental research often suggests an implicit commitment to a cleaner, less dissociative, sudden-transition view of development. Such an implicit commitment may derive…

  13. Towards an explicit account of implicit learning.

    PubMed

    Forkstam, Christian; Petersson, Karl Magnus

    2005-08-01

    The human brain supports acquisition mechanisms that can extract structural regularities implicitly from experience without the induction of an explicit model. Reber defined the process by which an individual comes to respond appropriately to the statistical structure of the input ensemble as implicit learning. He argued that the capacity to generalize to new input is based on the acquisition of abstract representations that reflect underlying structural regularities in the acquisition input. We focus this review of the implicit learning literature on studies published during 2004 and 2005. We will not review studies of repetition priming ('implicit memory'). Instead we focus on two commonly used experimental paradigms: the serial reaction time task and artificial grammar learning. Previous comprehensive reviews can be found in Seger's 1994 article and the Handbook of Implicit Learning. Emerging themes include the interaction between implicit and explicit processes, the role of the medial temporal lobe, developmental aspects of implicit learning, age-dependence, the role of sleep and consolidation. The attempts to characterize the interaction between implicit and explicit learning are promising although not well understood. The same can be said about the role of sleep and consolidation. Despite the fact that lesion studies have relatively consistently suggested that the medial temporal lobe memory system is not necessary for implicit learning, a number of functional magnetic resonance studies have reported medial temporal lobe activation in implicit learning. This issue merits further research. Finally, the clinical relevance of implicit learning remains to be determined.

  14. The Associations of Clinicians’ Implicit Attitudes About Race With Medical Visit Communication and Patient Ratings of Interpersonal Care

    PubMed Central

    Roter, Debra L.; Carson, Kathryn A.; Beach, Mary Catherine; Sabin, Janice A.; Greenwald, Anthony G.; Inui, Thomas S.

    2012-01-01

    Objectives. We examined the associations of clinicians’ implicit attitudes about race with visit communication and patient ratings of care. Methods. In a cross-sectional study of 40 primary care clinicians and 269 patients in urban community-based practices, we measured clinicians’ implicit general race bias and race and compliance stereotyping with 2 implicit association tests and related them to audiotape measures of visit communication and patient ratings. Results. Among Black patients, general race bias was associated with more clinician verbal dominance, lower patient positive affect, and poorer ratings of interpersonal care; race and compliance stereotyping was associated with longer visits, slower speech, less patient centeredness, and poorer ratings of interpersonal care. Among White patients, bias was associated with more verbal dominance and better ratings of interpersonal care; race and compliance stereotyping was associated with less verbal dominance, shorter visits, faster speech, more patient centeredness, higher clinician positive affect, and lower ratings of some aspects of interpersonal care. Conclusions. Clinician implicit race bias and race and compliance stereotyping are associated with markers of poor visit communication and poor ratings of care, particularly among Black patients. PMID:22420787

  15. Generalized lessons about sequence learning from the study of the serial reaction time task

    PubMed Central

    Schwarb, Hillary; Schumacher, Eric H.

    2012-01-01

    Over the last 20 years researchers have used the serial reaction time (SRT) task to investigate the nature of spatial sequence learning. They have used the task to identify the locus of spatial sequence learning, identify situations that enhance and those that impair learning, and identify the important cognitive processes that facilitate this type of learning. Although controversies remain, the SRT task has been integral in enhancing our understanding of implicit sequence learning. It is important, however, to ask what, if anything, the discoveries made using the SRT task tell us about implicit learning more generally. This review analyzes the state of the current spatial SRT sequence learning literature highlighting the stimulus-response rule hypothesis of sequence learning which we believe provides a unifying account of discrepant SRT data. It also challenges researchers to use the vast body of knowledge acquired with the SRT task to understand other implicit learning literatures too often ignored in the context of this particular task. This broad perspective will make it possible to identify congruences among data acquired using various different tasks that will allow us to generalize about the nature of implicit learning. PMID:22723815

  16. Racial-ethnic biases, time pressure, and medical decisions.

    PubMed

    Stepanikova, Irena

    2012-09-01

    This study examined two types of potential sources of racial-ethnic disparities in medical care: implicit biases and time pressure. Eighty-one family physicians and general internists responded to a case vignette describing a patient with chest pain. Time pressure was manipulated experimentally. Under high time pressure, but not under low time pressure, implicit biases regarding blacks and Hispanics led to a less serious diagnosis. In addition, implicit biases regarding blacks led to a lower likelihood of a referral to specialist when physicians were under high time pressure. The results suggest that when physicians face stress, their implicit biases may shape medical decisions in ways that disadvantage minority patients.

  17. Distinguishing Family from Friends : Implicit Cognitive Differences Regarding General Dispositions, Attitude Similarity, and Group Membership.

    PubMed

    O'Gorman, Rick; Roberts, Ruth

    2017-09-01

    Kinship and friendship are key human relationships. Increasingly, data suggest that people are not less altruistic toward friends than close kin. Some accounts suggest that psychologically we do not distinguish between them; countering this is evidence that kinship provides a unique explanatory factor. Using the Implicit Association Test, we examined how people implicitly think about close friends versus close kin in three contexts. In Experiment 1, we examined generic attitudinal dispositions toward friends and family. In Experiment 2, attitude similarity as a marker of family and friends was examined, and in Experiments 3 and 4, strength of in-group membership for family and friends was examined. Findings show that differences exist in implicit cognitive associations toward family and friends. There is some evidence that people hold more positive general dispositions toward friends, associate attitude similarity more with friends, consider family as more representative of the in-group than friends, but see friends as more in-group than distant kin.

  18. Implicit associations in social anxiety disorder: the effects of comorbid depression.

    PubMed

    Wong, Judy; Morrison, Amanda S; Heimberg, Richard G; Goldin, Philippe R; Gross, James J

    2014-08-01

    Implicit associations of the self to concepts like "calm" have been shown to be weaker in persons with social anxiety than in non-anxious healthy controls. However, other implicit self associations, such as those to acceptance or rejection, have been less studied in social anxiety, and none of this work has been conducted with clinical samples. Furthermore, the importance of depression in these relationships has not been well investigated. We addressed these issues by administering two Implicit Association Tests (IATs; Greenwald, McGhee, & Schwartz, 1998), one examining the implicit association of self/other to anxiety/calmness and the other examining the association of self/other to rejection/acceptance, to individuals with generalized social anxiety disorder (SAD, n=85), individuals with generalized SAD and a current or past diagnosis of major depressive disorder or current dysthymic disorder (n=47), and non-anxious, non-depressed healthy controls (n=44). The SAD and SAD-depression groups showed weaker implicit self-calmness associations than healthy controls, with the comorbid group showing the weakest self-calmness associations. The SAD-depression group showed the weakest implicit self-acceptance associations; no difference was found between non-depressed individuals with SAD and healthy controls. Post hoc analyses revealed that differences appeared to be driven by those with current depression. The SAD-only and SAD-depression groups did not differ in self-reported (explicit) social anxiety. The implications of these findings for the understanding of SAD-depression comorbidity and for the treatment of SAD are considered. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Electrostatic Solvation Energy for Two Oppositely Charged Ions in a Solvated Protein System: Salt Bridges Can Stabilize Proteins

    PubMed Central

    Gong, Haipeng; Freed, Karl F.

    2010-01-01

    Abstract Born-type electrostatic continuum methods have been an indispensable ingredient in a variety of implicit-solvent methods that reduce computational effort by orders of magnitude compared to explicit-solvent MD simulations and thus enable treatment using larger systems and/or longer times. An analysis of the limitations and failures of the Born approaches serves as a guide for fundamental improvements without diminishing the importance of prior works. One of the major limitations of the Born theory is the lack of a liquidlike description of the response of solvent dipoles to the electrostatic field of the solute and the changes therein, a feature contained in the continuum Langevin-Debye (LD) model applied here to investigate how Coulombic interactions depend on the location of charges relative to the protein/water boundary. This physically more realistic LD model is applied to study the stability of salt bridges. When compared head to head using the same (independently measurable) physical parameters (radii, dielectric constants, etc.), the LD model is in good agreement with observations, whereas the Born model is grossly in error. Our calculations also suggest that a salt bridge on the protein's surface can be stabilizing when the charge separation is ≤4 Å. PMID:20141761

  20. Three dimensional PNS solutions of hypersonic internal flows with equilibrium chemistry

    NASA Technical Reports Server (NTRS)

    Liou, May-Fun

    1989-01-01

    An implicit procedure for solving parabolized Navier-Stokes equations under the assumption of a general equation of state for a gas in chemical equilibrium is given. A general and consistent approach for the evaluation of Jacobian matrices in the implicit operator avoids the use of unnecessary auxiliary quantities and approximations, and leads to a simple expression. Applications to two- and three-dimensional flow problems show efficiency in computer time and economy in storage.

  1. Suboptimal care and maternal mortality among foreign-born women in Sweden: maternal death audit with application of the ‘migration three delays’ model

    PubMed Central

    2014-01-01

    Background Several European countries report differences in risk of maternal mortality between immigrants from low- and middle-income countries and host country women. The present study identified suboptimal factors related to care-seeking, accessibility, and quality of care for maternal deaths that occurred in Sweden from 1988–2010. Methods A subset of maternal death records (n = 75) among foreign-born women from low- and middle-income countries and Swedish-born women were audited using structured implicit review. One case of foreign-born maternal death was matched with two native born Swedish cases of maternal death. An assessment protocol was developed that applied both the ‘migration three delays’ framework and a modified version of the Confidential Enquiry from the United Kingdom. The main outcomes were major and minor suboptimal factors associated with maternal death in this high-income, low-maternal mortality context. Results Major and minor suboptimal factors were associated with a majority of maternal deaths and significantly more often to foreign-born women (p = 0.01). The main delays to care-seeking were non-compliance among foreign-born women and communication barriers, such as incongruent language and suboptimal interpreter system or usage. Inadequate care occurred more often among the foreign-born (p = 0.04), whereas delays in consultation/referral and miscommunication between health care providers where equally common between the two groups. Conclusions Suboptimal care factors, major and minor, were present in more than 2/3 of maternal deaths in this high-income setting. Those related to migration were associated to miscommunication, lack of professional interpreters, and limited knowledge about rare diseases and pregnancy complications. Increased insight into a migration perspective is advocated for maternity clinicians who provide care to foreign-born women. PMID:24725307

  2. Characterizing Implicit Mental Health Associations across Clinical Domains

    PubMed Central

    Werntz, Alexandra J.; Steinman, Shari A.; Glenn, Jeffrey J.; Nock, Matthew K.; Teachman, Bethany A.

    2016-01-01

    Background and objectives Implicit associations are relatively uncontrollable associations between concepts in memory. The current investigation focuses on implicit associations in four mental health domains (alcohol use, anxiety, depression, and eating disorders) and how these implicit associations: a) relate to explicit associations and b) self-reported clinical symptoms within the same domains, and c) vary based on demographic characteristics (age, gender, race, ethnicity, and education). Methods Participants (volunteers over age 18 to a research website) completed implicit association (Implicit Association Tests), explicit association (self+psychopathology or attitudes toward food, using semantic differential items), and symptom measures at the Project Implicit Mental Health website tied to: alcohol use (N=12,387), anxiety (N=21,304), depression (N=24,126), or eating disorders (N=10,115). Results Within each domain, implicit associations showed small to moderate associations with explicit associations and symptoms, and predicted self-reported symptoms beyond explicit associations. In general, implicit association strength varied little by race and ethnicity, but showed small ties to age, gender, and education. Limitations This research was conducted on a public research and education website, where participants could take more than one of the studies. Conclusions Among a large and diverse sample, implicit associations in the four domains are congruent with explicit associations and self-reported symptoms, and also add to our prediction of self-reported symptoms over and above explicit associations, pointing to the potential future clinical utility and validity of using implicit association measures with diverse populations. PMID:26962979

  3. Characterizing implicit mental health associations across clinical domains.

    PubMed

    Werntz, Alexandra J; Steinman, Shari A; Glenn, Jeffrey J; Nock, Matthew K; Teachman, Bethany A

    2016-09-01

    Implicit associations are relatively uncontrollable associations between concepts in memory. The current investigation focuses on implicit associations in four mental health domains (alcohol use, anxiety, depression, and eating disorders) and how these implicit associations: a) relate to explicit associations and b) self-reported clinical symptoms within the same domains, and c) vary based on demographic characteristics (age, gender, race, ethnicity, and education). Participants (volunteers over age 18 to a research website) completed implicit association (Implicit Association Tests), explicit association (self + psychopathology or attitudes toward food, using semantic differential items), and symptom measures at the Project Implicit Mental Health website tied to: alcohol use (N = 12,387), anxiety (N = 21,304), depression (N = 24,126), or eating disorders (N = 10,115). Within each domain, implicit associations showed small to moderate associations with explicit associations and symptoms, and predicted self-reported symptoms beyond explicit associations. In general, implicit association strength varied little by race and ethnicity, but showed small ties to age, gender, and education. This research was conducted on a public research and education website, where participants could take more than one of the studies. Among a large and diverse sample, implicit associations in the four domains are congruent with explicit associations and self-reported symptoms, and also add to our prediction of self-reported symptoms over and above explicit associations, pointing to the potential future clinical utility and validity of using implicit association measures with diverse populations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Intact and impaired conceptual memory processes in amnesia.

    PubMed

    Keane, M M; Gabrieli, J D; Monti, L A; Fleischman, D A; Cantor, J M; Noland, J S

    1997-01-01

    To examine the status of conceptual memory processes in amnesia, a conceptual memory task with implicit or explicit task instructions was given to amnesic and control groups. After studying a list of category exemplars, participants saw category labels and were asked to generate as many exemplars as possible (an implicit memory task) or to generate exemplars that had been in the prior study list (an explicit memory task). After incidental deep or shallow encoding of exemplars, amnesic patients showed normal implicit memory performance (priming), a normal levels-of-processing effect on priming, and impaired explicit memory performance. After intentional encoding of exemplars, amnesic patients showed impaired implicit and explicit memory performance. Results suggest that although amnesic patients can show impairments on implicit and explicit conceptual memory tasks, their deficit does not generalize to all conceptual memory tasks.

  5. Three-dimensional implicit lambda methods

    NASA Technical Reports Server (NTRS)

    Napolitano, M.; Dadone, A.

    1983-01-01

    This paper derives the three dimensional lambda-formulation equations for a general orthogonal curvilinear coordinate system and provides various block-explicit and block-implicit methods for solving them, numerically. Three model problems, characterized by subsonic, supersonic and transonic flow conditions, are used to assess the reliability and compare the efficiency of the proposed methods.

  6. Intergroup contact throughout the lifespan modulates implicit racial biases across perceivers' racial group.

    PubMed

    Kubota, Jennifer T; Peiso, Jaelyn; Marcum, Kori; Cloutier, Jasmin

    2017-01-01

    Few researchers have investigated how contact across the lifespan influences racial bias and whether diversity of contact is beneficial regardless of the race of the perceiver. This research aims to address these gaps in the literature with a focus on how diversity in childhood and current contact shapes implicit racial bias across perceivers' racial group. In two investigations, participants completed an Implicit Association Test and a self-report measure of the racial diversity of their current and childhood contact. In both studies, increased contact with Black compared with White individuals, both in childhood (Study 2) and currently (Studies 1 and 2), was associated with reduced implicit pro-White racial bias. For Black individuals (Study 2) more contact with Black compared with White individuals also was associated with reduced implicit pro-White racial bias. These findings suggest that diversity in contact across the lifespan may be related to reductions in implicit racial biases and that this relationship may generalize across racial groups.

  7. Cognitive load disrupts implicit theory-of-mind processing.

    PubMed

    Schneider, Dana; Lam, Rebecca; Bayliss, Andrew P; Dux, Paul E

    2012-08-01

    Eye movements in Sally-Anne false-belief tasks appear to reflect the ability to implicitly monitor the mental states of other individuals (theory of mind, or ToM). It has recently been proposed that an early-developing, efficient, and automatically operating ToM system subserves this ability. Surprisingly absent from the literature, however, is an empirical test of the influence of domain-general executive processing resources on this implicit ToM system. In the study reported here, a dual-task method was employed to investigate the impact of executive load on eye movements in an implicit Sally-Anne false-belief task. Under no-load conditions, adult participants displayed eye movement behavior consistent with implicit belief processing, whereas evidence for belief processing was absent for participants under cognitive load. These findings indicate that the cognitive system responsible for implicitly tracking beliefs draws at least minimally on executive processing resources. Thus, even the most low-level processing of beliefs appears to reflect a capacity-limited operation.

  8. Intergroup contact throughout the lifespan modulates implicit racial biases across perceivers’ racial group

    PubMed Central

    Peiso, Jaelyn; Marcum, Kori; Cloutier, Jasmin

    2017-01-01

    Few researchers have investigated how contact across the lifespan influences racial bias and whether diversity of contact is beneficial regardless of the race of the perceiver. This research aims to address these gaps in the literature with a focus on how diversity in childhood and current contact shapes implicit racial bias across perceivers’ racial group. In two investigations, participants completed an Implicit Association Test and a self-report measure of the racial diversity of their current and childhood contact. In both studies, increased contact with Black compared with White individuals, both in childhood (Study 2) and currently (Studies 1 and 2), was associated with reduced implicit pro-White racial bias. For Black individuals (Study 2) more contact with Black compared with White individuals also was associated with reduced implicit pro-White racial bias. These findings suggest that diversity in contact across the lifespan may be related to reductions in implicit racial biases and that this relationship may generalize across racial groups. PMID:28700624

  9. Preserved conceptual implicit memory for pictures in patients with Alzheimer’s disease

    PubMed Central

    Deason, Rebecca G.; Hussey, Erin P.; Flannery, Sean; Ally, Brandon A.

    2015-01-01

    The current study examined different aspects of conceptual implicit memory in patients with mild Alzheimer’s disease (AD). Specifically, we were interested in whether priming of distinctive conceptual features versus general semantic information related to pictures and words would differ for the mild AD patients and healthy older adults. In this study, 14 healthy older adults and 15 patients with mild AD studied both pictures and words followed by an implicit test section, where they were asked about distinctive conceptual or general semantic information related to the items they had previously studied (or novel items) Healthy older adults and patients with mild AD showed both conceptual priming and the picture superiority effect, but the AD patients only showed these effects for the questions focused on the distinctive conceptual information. We found that patients with mild AD showed intact conceptual picture priming in a task that required generating a response (answer) from a cue (question) for cues that focused on distinctive conceptual information. This experiment has helped improve our understanding of both the picture superiority effect and conceptual implicit memory in patients with mild AD in that these findings support the notion that conceptual implicit memory might potentially help to drive familiarity-based recognition in the face of impaired recollection in patients with mild AD. PMID:26291521

  10. Preserved conceptual implicit memory for pictures in patients with Alzheimer's disease.

    PubMed

    Deason, Rebecca G; Hussey, Erin P; Flannery, Sean; Ally, Brandon A

    2015-10-01

    The current study examined different aspects of conceptual implicit memory in patients with mild Alzheimer's disease (AD). Specifically, we were interested in whether priming of distinctive conceptual features versus general semantic information related to pictures and words would differ for the mild AD patients and healthy older adults. In this study, 14 healthy older adults and 15 patients with mild AD studied both pictures and words followed by an implicit test section, where they were asked about distinctive conceptual or general semantic information related to the items they had previously studied (or novel items). Healthy older adults and patients with mild AD showed both conceptual priming and the picture superiority effect, but the AD patients only showed these effects for the questions focused on the distinctive conceptual information. We found that patients with mild AD showed intact conceptual picture priming in a task that required generating a response (answer) from a cue (question) for cues that focused on distinctive conceptual information. This experiment has helped improve our understanding of both the picture superiority effect and conceptual implicit memory in patients with mild AD in that these findings support the notion that conceptual implicit memory might potentially help to drive familiarity-based recognition in the face of impaired recollection in patients with mild AD. Copyright © 2015. Published by Elsevier Inc.

  11. Implicit and explicit processing of emotional facial expressions in Parkinson's disease.

    PubMed

    Wagenbreth, Caroline; Wattenberg, Lena; Heinze, Hans-Jochen; Zaehle, Tino

    2016-04-15

    Besides motor problems, Parkinson's disease (PD) is associated with detrimental emotional and cognitive functioning. Deficient explicit emotional processing has been observed, whilst patients also show impaired Theory of Mind (ToM) abilities. However, it is unclear whether this PD patients' ToM deficit is based on an inability to infer otherś emotional states or whether it is due to explicit emotional processing deficits. We investigated implicit and explicit emotional processing in PD with an affective priming paradigm in which we used pictures of human eyes for emotional primes and a lexical decision task (LDT) with emotional connoted words for target stimuli. Sixteen PD patients and sixteen matched healthy controls performed a LTD combined with an emotional priming paradigm providing emotional information through the facial eye region to assess implicit emotional processing. Second, participants explicitly evaluated the emotional status of eyes and words used in the implicit task. Compared to controls implicit emotional processing abilities were generally preserved in PD with, however, considerable alterations for happiness and disgust processing. Furthermore, we observed a general impairment of patients for explicit evaluation of emotional stimuli, which was augmented for the rating of facial expressions. This is the first study reporting results for affective priming with facial eye expressions in PD patients. Our findings indicate largely preserved implicit emotional processing, with a specific altered processing of disgust and happiness. Explicit emotional processing was considerably impaired for semantic and especially for facial stimulus material. Poor ToM abilities in PD patients might be based on deficient explicit emotional processing, with preserved ability to implicitly infer other people's feelings. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. The mixed impact of medical school on medical students' implicit and explicit weight bias.

    PubMed

    Phelan, Sean M; Puhl, Rebecca M; Burke, Sara E; Hardeman, Rachel; Dovidio, John F; Nelson, David B; Przedworski, Julia; Burgess, Diana J; Perry, Sylvia; Yeazel, Mark W; van Ryn, Michelle

    2015-10-01

    Health care trainees demonstrate implicit (automatic, unconscious) and explicit (conscious) bias against people from stigmatised and marginalised social groups, which can negatively influence communication and decision making. Medical schools are well positioned to intervene and reduce bias in new physicians. This study was designed to assess medical school factors that influence change in implicit and explicit bias against individuals from one stigmatised group: people with obesity. This was a prospective cohort study of medical students enrolled at 49 US medical schools randomly selected from all US medical schools within the strata of public and private schools and region. Participants were 1795 medical students surveyed at the beginning of their first year and end of their fourth year. Web-based surveys included measures of weight bias, and medical school experiences and climate. Bias change was compared with changes in bias in the general public over the same period. Linear mixed models were used to assess the impact of curriculum, contact with people with obesity, and faculty role modelling on weight bias change. Increased implicit and explicit biases were associated with less positive contact with patients with obesity and more exposure to faculty role modelling of discriminatory behaviour or negative comments about patients with obesity. Increased implicit bias was associated with training in how to deal with difficult patients. On average, implicit weight bias decreased and explicit bias increased during medical school, over a period of time in which implicit weight bias in the general public increased and explicit bias remained stable. Medical schools may reduce students' weight biases by increasing positive contact between students and patients with obesity, eliminating unprofessional role modelling by faculty members and residents, and altering curricula focused on treating difficult patients. © 2015 John Wiley & Sons Ltd.

  13. Can we undo our first impressions?: The role of reinterpretation in reversing implicit evaluations

    PubMed Central

    Mann, Thomas C.; Ferguson, Melissa J.

    2015-01-01

    Little work has examined whether implicit evaluations can be effectively “undone” after learning new revelations. Across 7 experiments, participants fully reversed their implicit evaluation of a novel target person after reinterpreting earlier information. Revision occurred across multiple implicit evaluation measures (Experiments 1a and 1b), and only when the new information prompted a reinterpretation of prior learning versus did not (Experiment 2). The updating required active consideration of the information, as it emerged only with at least moderate cognitive resources (Experiment 3). Self-reported reinterpretation predicted (Experiment 4) and mediated (Experiment 5) revised implicit evaluations beyond the separate influence of how thoughtfully participants considered the new information in general. Finally, the revised evaluations were durable three days later (Experiment 6). We discuss how these results inform existing theoretical models, and consider implications for future research. PMID:25798625

  14. Can we undo our first impressions? The role of reinterpretation in reversing implicit evaluations.

    PubMed

    Mann, Thomas C; Ferguson, Melissa J

    2015-06-01

    Little work has examined whether implicit evaluations can be effectively "undone" after learning new revelations. Across 7 experiments, participants fully reversed their implicit evaluation of a novel target person after reinterpreting earlier information. Revision occurred across multiple implicit evaluation measures (Experiments 1a and 1b), and only when the new information prompted a reinterpretation of prior learning versus did not (Experiment 2). The updating required active consideration of the information, as it emerged only with at least moderate cognitive resources (Experiment 3). Self-reported reinterpretation predicted (Experiment 4) and mediated (Experiment 5) revised implicit evaluations beyond the separate influence of how thoughtfully participants considered the new information in general. Finally, the revised evaluations were durable 3 days later (Experiment 6). We discuss how these results inform existing theoretical models, and consider implications for future research. (c) 2015 APA, all rights reserved).

  15. Examples of grid generation with implicitly specified surfaces using GridPro (TM)/az3000. 1: Filleted multi-tube configurations

    NASA Technical Reports Server (NTRS)

    Cheng, Zheming; Eiseman, Peter R.

    1995-01-01

    With examples, we illustrate how implicitly specified surfaces can be used for grid generation with GridPro/az3000. The particular examples address two questions: (1) How do you model intersecting tubes with fillets? and (2) How do you generate grids inside the intersected tubes? The implication is much more general. With the results in a forthcoming paper which develops an easy-to-follow procedure for implicit surface modeling, we provide a powerful means for rapid prototyping in grid generation.

  16. Stabilization of coiled-coil peptide domains by introduction of trifluoroleucine.

    PubMed

    Tang, Y; Ghirlanda, G; Vaidehi, N; Kua, J; Mainz, D T; Goddard III, W A; DeGrado, W F; Tirrell, D A

    2001-03-06

    Substitution of leucine residues by 5,5,5-trifluoroleucine at the d-positions of the leucine zipper peptide GCN4-p1d increases the thermal stability of the coiled-coil structure. The midpoint thermal unfolding temperature of the fluorinated peptide is elevated by 13 degrees C at 30 microM peptide concentration. The modified peptide is more resistant to chaotropic denaturants, and the free energy of folding of the fluorinated peptide is 0.5-1.2 kcal/mol larger than that of the hydrogenated form. A similarly fluorinated form of the DNA-binding peptide GCN4-bZip binds to target DNA sequences with affinity and specificity identical to those of the hydrogenated form, while demonstrating enhanced thermal stability. Molecular dynamics simulation on the fluorinated GCN4-p1d peptide using the Surface Generalized Born implicit solvation model revealed that the coiled-coil binding energy is 55% more favorable upon fluorination. These results suggest that fluorination of hydrophobic substructures in peptides and proteins may provide new means of increasing protein stability, enhancing protein assembly, and strengthening receptor-ligand interactions.

  17. Guess what? Implicit motivation boosts the influence of subliminal information on choice.

    PubMed

    Milyavsky, Maxim; Hassin, Ran R; Schul, Yaacov

    2012-09-01

    When is choice affected by subliminal messages? This question has fascinated scientists and lay people alike, but it is only recently that reliable empirical data began to emerge. In the current paper we bridge the literature on implicit motivation and that on subliminal persuasion. We suggest that motivation in general, and implicit motivation more specifically, plays an important role in subliminal persuasion: It sensitizes us to subliminal cues. To examine this hypothesis we developed a new paradigm that allows powerful tests of subliminal influences as well as stringent assessments of subliminality. The results of two experiments suggest that implicit motivation can enhance the effects of subliminal priming on choice. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. Verbal implicit sequence learning in persons who stutter and persons with Parkinson's disease.

    PubMed

    Smits-Bandstra, Sarah; Gracco, Vincent

    2013-01-01

    The authors investigated the integrity of implicit learning systems in 14 persons with Parkinson's disease (PPD), 14 persons who stutter (PWS), and 14 control participants. In a 120-min session participants completed a verbal serial reaction time task, naming aloud 4 syllables in response to 4 visual stimuli. Unbeknownst to participants, the syllables formed a repeating 8-item sequence. PWS and PPD demonstrated slower reaction times for early but not late learning trials relative to controls reflecting delays but not deficiencies in general learning. PPD also demonstrated less accuracy in general learning relative to controls. All groups demonstrated similar limited explicit sequence knowledge. Both PWS and PPD demonstrated significantly less implicit sequence learning relative to controls, suggesting that stuttering may be associated with compromised functional integrity of the cortico-striato-thalamo-cortical loop.

  19. Explicit pre-training instruction does not improve implicit perceptual-motor sequence learning

    PubMed Central

    Sanchez, Daniel J.; Reber, Paul J.

    2012-01-01

    Memory systems theory argues for separate neural systems supporting implicit and explicit memory in the human brain. Neuropsychological studies support this dissociation, but empirical studies of cognitively healthy participants generally observe that both kinds of memory are acquired to at least some extent, even in implicit learning tasks. A key question is whether this observation reflects parallel intact memory systems or an integrated representation of memory in healthy participants. Learning of complex tasks in which both explicit instruction and practice is used depends on both kinds of memory, and how these systems interact will be an important component of the learning process. Theories that posit an integrated, or single, memory system for both types of memory predict that explicit instruction should contribute directly to strengthening task knowledge. In contrast, if the two types of memory are independent and acquired in parallel, explicit knowledge should have no direct impact and may serve in a “scaffolding” role in complex learning. Using an implicit perceptual-motor sequence learning task, the effect of explicit pre-training instruction on skill learning and performance was assessed. Explicit pre-training instruction led to robust explicit knowledge, but sequence learning did not benefit from the contribution of pre-training sequence memorization. The lack of an instruction benefit suggests that during skill learning, implicit and explicit memory operate independently. While healthy participants will generally accrue parallel implicit and explicit knowledge in complex tasks, these types of information appear to be separately represented in the human brain consistent with multiple memory systems theory. PMID:23280147

  20. A specific implicit sequence learning deficit as an underlying cause of dyslexia? Investigating the role of attention in implicit learning tasks.

    PubMed

    Staels, Eva; Van den Broeck, Wim

    2017-05-01

    Recently, a general implicit sequence learning deficit was proposed as an underlying cause of dyslexia. This new hypothesis was investigated in the present study by including a number of methodological improvements, for example, the inclusion of appropriate control conditions. The second goal of the study was to explore the role of attentional functioning in implicit and explicit learning tasks. In a 2 × 2 within-subjects design 4 tasks were administered in 30 dyslexic and 38 control children: an implicit and explicit serial reaction time (RT) task and an implicit and explicit contextual cueing task. Attentional functioning was also administered. The entire learning curves of all tasks were analyzed using latent growth curve modeling in order to compare performances between groups and to examine the role of attentional functioning on the learning curves. The amount of implicit learning was similar for both groups. However, the dyslexic group showed slower RTs throughout the entire task. This group difference reduced and became nonsignificant after controlling for attentional functioning. Both implicit learning tasks, but none of the explicit learning tasks, were significantly affected by attentional functioning. Dyslexic children do not suffer from a specific implicit sequence learning deficit. The slower RTs of the dyslexic children throughout the entire implicit sequence learning process are caused by their comorbid attention problems and overall slowness. A key finding of the present study is that, in contrast to what was assumed for a long time, implicit learning relies on attentional resources, perhaps even more than explicit learning does. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  1. Sustainability of Breadth and Depth of Vocabulary after Implicit versus Explicit Instruction in Kindergarten

    ERIC Educational Resources Information Center

    Damhuis, Carmen M. P.; Segers, Eliane; Verhoeven, Ludo

    2014-01-01

    We investigated the sustained effects of explicit versus implicit instruction on the breadth and depth of children's vocabularies, while taking their general vocabulary and verbal short-term memory into account. Two experimental groups with 12 and 15 kindergarten children respectively learned two sets of 17 words counterbalanced to be taught first…

  2. Efficient implementation of constant pH molecular dynamics on modern graphics processors.

    PubMed

    Arthur, Evan J; Brooks, Charles L

    2016-09-15

    The treatment of pH sensitive ionization states for titratable residues in proteins is often omitted from molecular dynamics (MD) simulations. While static charge models can answer many questions regarding protein conformational equilibrium and protein-ligand interactions, pH-sensitive phenomena such as acid-activated chaperones and amyloidogenic protein aggregation are inaccessible to such models. Constant pH molecular dynamics (CPHMD) coupled with the Generalized Born with a Simple sWitching function (GBSW) implicit solvent model provide an accurate framework for simulating pH sensitive processes in biological systems. Although this combination has demonstrated success in predicting pKa values of protein structures, and in exploring dynamics of ionizable side-chains, its speed has been an impediment to routine application. The recent availability of low-cost graphics processing unit (GPU) chipsets with thousands of processing cores, together with the implementation of the accurate GBSW implicit solvent model on those chipsets (Arthur and Brooks, J. Comput. Chem. 2016, 37, 927), provide an opportunity to improve the speed of CPHMD and ionization modeling greatly. Here, we present a first implementation of GPU-enabled CPHMD within the CHARMM-OpenMM simulation package interface. Depending on the system size and nonbonded force cutoff parameters, we find speed increases of between one and three orders of magnitude. Additionally, the algorithm scales better with system size than the CPU-based algorithm, thus allowing for larger systems to be modeled in a cost effective manner. We anticipate that the improved performance of this methodology will open the door for broad-spread application of CPHMD in its modeling pH-mediated biological processes. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Implicit attitudes toward smoking: how the smell of cigarettes influences responses of college-age smokers and nonsmokers.

    PubMed

    Glock, Sabine; Kovacs, Carrie; Unz, Dagmar

    2014-05-01

    The habit of smoking may have automatic behavioral components guided by implicit attitudes. Smokers' attitudes toward smoking should thus be less negative than nonsmokers', so that a salient smoking cue (smell) is able to activate positive aspects of these attitudes. An affective priming task was used to explore this hypothesis. Unexpectedly, smokers and nonsmokers showed equally negative implicit attitudes, irrespective of smell. Smokers exposed to the cigarette smell did, however, display generally slower responses than nonsmokers, suggesting attentional bias. This could have implications for smoking policies in contexts where attentional factors affect performance.

  4. Investigating implicit statistical learning mechanisms through contextual cueing.

    PubMed

    Goujon, Annabelle; Didierjean, André; Thorpe, Simon

    2015-09-01

    Since its inception, the contextual cueing (CC) paradigm has generated considerable interest in various fields of cognitive sciences because it constitutes an elegant approach to understanding how statistical learning (SL) mechanisms can detect contextual regularities during a visual search. In this article we review and discuss five aspects of CC: (i) the implicit nature of learning, (ii) the mechanisms involved in CC, (iii) the mediating factors affecting CC, (iv) the generalization of CC phenomena, and (v) the dissociation between implicit and explicit CC phenomena. The findings suggest that implicit SL is an inherent component of ongoing processing which operates through clustering, associative, and reinforcement processes at various levels of sensory-motor processing, and might result from simple spike-timing-dependent plasticity. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Development and Verification of the Charring Ablating Thermal Protection Implicit System Solver

    NASA Technical Reports Server (NTRS)

    Amar, Adam J.; Calvert, Nathan D.; Kirk, Benjamin S.

    2010-01-01

    The development and verification of the Charring Ablating Thermal Protection Implicit System Solver is presented. This work concentrates on the derivation and verification of the stationary grid terms in the equations that govern three-dimensional heat and mass transfer for charring thermal protection systems including pyrolysis gas flow through the porous char layer. The governing equations are discretized according to the Galerkin finite element method with first and second order implicit time integrators. The governing equations are fully coupled and are solved in parallel via Newton's method, while the fully implicit linear system is solved with the Generalized Minimal Residual method. Verification results from exact solutions and the Method of Manufactured Solutions are presented to show spatial and temporal orders of accuracy as well as nonlinear convergence rates.

  6. Interpreting the Coulomb-field approximation for generalized-Born electrostatics using boundary-integral equation theory.

    PubMed

    Bardhan, Jaydeep P

    2008-10-14

    The importance of molecular electrostatic interactions in aqueous solution has motivated extensive research into physical models and numerical methods for their estimation. The computational costs associated with simulations that include many explicit water molecules have driven the development of implicit-solvent models, with generalized-Born (GB) models among the most popular of these. In this paper, we analyze a boundary-integral equation interpretation for the Coulomb-field approximation (CFA), which plays a central role in most GB models. This interpretation offers new insights into the nature of the CFA, which traditionally has been assessed using only a single point charge in the solute. The boundary-integral interpretation of the CFA allows the use of multiple point charges, or even continuous charge distributions, leading naturally to methods that eliminate the interpolation inaccuracies associated with the Still equation. This approach, which we call boundary-integral-based electrostatic estimation by the CFA (BIBEE/CFA), is most accurate when the molecular charge distribution generates a smooth normal displacement field at the solute-solvent boundary, and CFA-based GB methods perform similarly. Conversely, both methods are least accurate for charge distributions that give rise to rapidly varying or highly localized normal displacement fields. Supporting this analysis are comparisons of the reaction-potential matrices calculated using GB methods and boundary-element-method (BEM) simulations. An approximation similar to BIBEE/CFA exhibits complementary behavior, with superior accuracy for charge distributions that generate rapidly varying normal fields and poorer accuracy for distributions that produce smooth fields. This approximation, BIBEE by preconditioning (BIBEE/P), essentially generates initial guesses for preconditioned Krylov-subspace iterative BEMs. Thus, iterative refinement of the BIBEE/P results recovers the BEM solution; excellent agreement is obtained in only a few iterations. The boundary-integral-equation framework may also provide a means to derive rigorous results explaining how the empirical correction terms in many modern GB models significantly improve accuracy despite their simple analytical forms.

  7. An implicit time-marching method for studying unsteady flow with massive separation

    NASA Technical Reports Server (NTRS)

    Osswald, G. A.; Ghia, K. N.; Chia, U.

    1985-01-01

    A fully implicit time-marching method is developed such that all spatial derivatives are approximated using central differences, but no use is made of any artificial dissipation. The numerical method solves the discretized equations using Alternating Direction Implicit-Block Gaussian Elimination technique. The method is implemented in the unsteady analysis, which solves the incompressible Navier-Stokes equations in terms of vorticity and stream function in generalized orthogonal coordinates. A clustered conformal C-grid is employed, and every effort is made to resolve the various length scales in the flow problem. The metric discontinuity at the branch-cut is treated appropriately using analytic continuation. Introduction of the BGE reordering permits implicit treatment of the branch cut in the numerical method. The vorticity singularity at the cusped trailing edge is also appropriately treated. This accurate and efficient implicit method is used to study flow at Re = 1000, past a 12-percent thick symmetric Joukowski airfoil at high angle of attack 30 and 53 deg.

  8. Implicit measures of the stereotype content associated with disability.

    PubMed

    Rohmer, Odile; Louvet, Eva

    2012-12-01

    The present research aimed to show that the mixed stereotype content of persons with disability observed at an explicit level does not manifest itself using implicit measures. Two experimental studies were conducted to analyse the stereotype content of persons with a disability at the implicit level. The procedure used in this study was the concept priming paradigm. Furthermore, Study 2 also included an explicit measure. Results show important discrepancies between implicit and explicit measures. At an explicit level, previous work supporting the mixed stereotype content of persons with disability was replicated: participants judged these persons as warmer but less competent than persons without a disability. At an implicit level, a quite different pattern of results emerged: persons with a disability were associated not only with less competence than persons without disability, but also with less warmth. These findings suggest that the mixed pattern between warmth and competence generally observed at an explicit level may be based on societal pressures against prejudice and discrimination. ©2012 The British Psychological Society.

  9. Empirical comparison between different methods for genomic prediction of number of piglets born alive in moderate sized breeding populations.

    PubMed

    Fangmann, A; Sharifi, R A; Heinkel, J; Danowski, K; Schrade, H; Erbe, M; Simianer, H

    2017-04-01

    Currently used multi-step methods to incorporate genomic information in the prediction of breeding values (BV) implicitly involve many assumptions which, if violated, may result in loss of information, inaccuracies and bias. To overcome this, single-step genomic best linear unbiased prediction (ssGBLUP) was proposed combining pedigree, phenotype and genotype of all individuals for genetic evaluation. Our objective was to implement ssGBLUP for genomic predictions in pigs and to compare the accuracy of ssGBLUP with that of multi-step methods with empirical data of moderately sized pig breeding populations. Different predictions were performed: conventional parent average (PA), direct genomic value (DGV) calculated with genomic BLUP (GBLUP), a GEBV obtained by blending the DGV with PA, and ssGBLUP. Data comprised individuals from a German Landrace (LR) and Large White (LW) population. The trait 'number of piglets born alive' (NBA) was available for 182,054 litters of 41,090 LR sows and 15,750 litters from 4534 LW sows. The pedigree contained 174,021 animals, of which 147,461 (26,560) animals were LR (LW) animals. In total, 526 LR and 455 LW animals were genotyped with the Illumina PorcineSNP60 BeadChip. After quality control and imputation, 495 LR (424 LW) animals with 44,368 (43,678) SNP on 18 autosomes remained for the analysis. Predictive abilities, i.e., correlations between de-regressed proofs and genomic BV, were calculated with a five-fold cross validation and with a forward prediction for young genotyped validation animals born after 2011. Generally, predictive abilities for LR were rather small (0.08 for GBLUP, 0.19 for GEBV and 0.18 for ssGBLUP). For LW, ssGBLUP had the greatest predictive ability (0.45). For both breeds, assessment of reliabilities for young genotyped animals indicated that genomic prediction outperforms PA with ssGBLUP providing greater reliabilities (0.40 for LR and 0.32 for LW) than GEBV (0.35 for LR and 0.29 for LW). Grouping of animals according to information sources revealed that genomic prediction had the highest potential benefit for genotyped animals without their own phenotype. Although, ssGBLUP did not generally outperform GBLUP or GEBV, the results suggest that ssGBLUP can be a useful and conceptually convincing approach for practical genomic prediction of NBA in moderately sized LR and LW populations.

  10. Representations for implicit constitutive relations describing non-dissipative response of isotropic materials

    NASA Astrophysics Data System (ADS)

    Gokulnath, C.; Saravanan, U.; Rajagopal, K. R.

    2017-12-01

    A methodology for obtaining implicit constitutive representations involving the Cauchy stress and the Hencky strain for isotropic materials undergoing a non-dissipative process is developed. Using this methodology, a general constitutive representation for a subclass of implicit models relating the Cauchy stress and the Hencky strain is obtained for an isotropic material with no internal constraints. It is shown that even for this subclass, unlike classical Green elasticity, one has to specify three potentials to relate the Cauchy stress and the Hencky strain. Then, a procedure to obtain implicit constitutive representations for isotropic materials with internal constraints is presented. As an illustration, it is shown that for incompressible materials the Cauchy stress and the Hencky strain could be related through a single potential. Finally, constitutive approximations are obtained when the displacement gradient is small.

  11. On a fourth order accurate implicit finite difference scheme for hyperbolic conservation laws. II - Five-point schemes

    NASA Technical Reports Server (NTRS)

    Harten, A.; Tal-Ezer, H.

    1981-01-01

    This paper presents a family of two-level five-point implicit schemes for the solution of one-dimensional systems of hyperbolic conservation laws, which generalized the Crank-Nicholson scheme to fourth order accuracy (4-4) in both time and space. These 4-4 schemes are nondissipative and unconditionally stable. Special attention is given to the system of linear equations associated with these 4-4 implicit schemes. The regularity of this system is analyzed and efficiency of solution-algorithms is examined. A two-datum representation of these 4-4 implicit schemes brings about a compactification of the stencil to three mesh points at each time-level. This compact two-datum representation is particularly useful in deriving boundary treatments. Numerical results are presented to illustrate some properties of the proposed scheme.

  12. What colour does that feel? Tactile--visual mapping and the development of cross-modality.

    PubMed

    Ludwig, Vera U; Simner, Julia

    2013-04-01

    Humans share implicit preferences for cross-modal mappings (e.g., low pitch sounds are preferentially paired with darker colours). Individuals with synaesthesia experience cross-modal mappings to a conscious degree (e.g., they may see colours when they hear sounds). The neonatal synaesthesia hypothesis claims that all humans may be born with this explicit cross-modal perception, which dies out in most people through childhood, leaving only implicit associations in the average adult. Although there is evidence for decreasing cross-modality throughout early infancy, it is unclear whether this decline continues to take place throughout childhood and adolescence. This large-scale study had two goals. First, we aimed to establish whether human non-synaesthetes systematically map tactile and visual dimensions - a combination that has rarely been studied. Second, we asked whether tactile-visual associations may be more pronounced in younger compared to older participants. 210 participants between the ages of 5-74 years assigned colours to tactile stimuli. Smoothness, softness and roundness of stimuli positively correlated with luminance of the chosen colour; and smoothness and softness also positively correlated with chroma. Moreover, tactile sensations were associated with specific colours (e.g., softness with pink). There were no age differences for luminance effects. Chroma effects, however, were found exclusively in children and adolescents. Our findings are consistent with the neonatal synaesthesia hypothesis which suggests that all humans are born with strong cross-modal perception which is pruned away or inhibited throughout development. Moreover, the findings suggest that a decline of some forms of cross-modality may take place over a much longer time span than previously assumed. Copyright © 2012 Elsevier Ltd. All rights reserved.

  13. Comparing implicit and explicit semantic access of direct and indirect word pairs in schizophrenia to evaluate models of semantic memory.

    PubMed

    Neill, Erica; Rossell, Susan Lee

    2013-02-28

    Semantic memory deficits in schizophrenia (SZ) are profound, yet there is no research comparing implicit and explicit semantic processing in the same participant sample. In the current study, both implicit and explicit priming are investigated using direct (LION-TIGER) and indirect (LION-STRIPES; where tiger is not displayed) stimuli comparing SZ to healthy controls. Based on a substantive review (Rossell and Stefanovic, 2007) and meta-analysis (Pomarol-Clotet et al., 2008), it was predicted that SZ would be associated with increased indirect priming implicitly. Further, it was predicted that SZ would be associated with abnormal indirect priming explicitly, replicating earlier work (Assaf et al., 2006). No specific hypotheses were made for implicit direct priming due to the heterogeneity of the literature. It was hypothesised that explicit direct priming would be intact based on the structured nature of this task. The pattern of results suggests (1) intact reaction time (RT) and error performance implicitly in the face of abnormal direct priming and (2) impaired RT and error performance explicitly. This pattern confirms general findings regarding implicit/explicit memory impairments in SZ whilst highlighting the unique pattern of performance specific to semantic priming. Finally, priming performance is discussed in relation to thought disorder and length of illness. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. Free-form geometric modeling by integrating parametric and implicit PDEs.

    PubMed

    Du, Haixia; Qin, Hong

    2007-01-01

    Parametric PDE techniques, which use partial differential equations (PDEs) defined over a 2D or 3D parametric domain to model graphical objects and processes, can unify geometric attributes and functional constraints of the models. PDEs can also model implicit shapes defined by level sets of scalar intensity fields. In this paper, we present an approach that integrates parametric and implicit trivariate PDEs to define geometric solid models containing both geometric information and intensity distribution subject to flexible boundary conditions. The integrated formulation of second-order or fourth-order elliptic PDEs permits designers to manipulate PDE objects of complex geometry and/or arbitrary topology through direct sculpting and free-form modeling. We developed a PDE-based geometric modeling system for shape design and manipulation of PDE objects. The integration of implicit PDEs with parametric geometry offers more general and arbitrary shape blending and free-form modeling for objects with intensity attributes than pure geometric models.

  15. The role of attention during encoding in implicit and explicit memory.

    PubMed

    Mulligan, N W

    1998-01-01

    In 5 experiments, participants read study words under conditions of divided or full attention. Dividing attention reduced performance on the general knowledge test, a conceptual implicit test of memory. Likewise, dividing attention reduced conceptual priming on the word--association task, as well as on a matched explicit test, associate-cued recall. In contrast, even very strong division of attention did not reduce perceptual priming on word-fragment completion, although it did reduce recall on the matched explicit test of word-fragment-cued recall. Finally, dividing attention reduced recall on the perceptual explicit tests of graphemic-cued recall and graphemic recognition. The results indicate that perceptual implicit tests rely minimally on attention-demanding encoding processes relative to other types of memory tests. The obtained pattern of dissociations is not readily accommodated by the transfer-appropriate-processing (TAP) account of implicit and explicit memory. Potential extensions of the TAP view are discussed.

  16. Multimodal sequence learning.

    PubMed

    Kemény, Ferenc; Meier, Beat

    2016-02-01

    While sequence learning research models complex phenomena, previous studies have mostly focused on unimodal sequences. The goal of the current experiment is to put implicit sequence learning into a multimodal context: to test whether it can operate across different modalities. We used the Task Sequence Learning paradigm to test whether sequence learning varies across modalities, and whether participants are able to learn multimodal sequences. Our results show that implicit sequence learning is very similar regardless of the source modality. However, the presence of correlated task and response sequences was required for learning to take place. The experiment provides new evidence for implicit sequence learning of abstract conceptual representations. In general, the results suggest that correlated sequences are necessary for implicit sequence learning to occur. Moreover, they show that elements from different modalities can be automatically integrated into one unitary multimodal sequence. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Robust Integration Schemes for Generalized Viscoplasticity with Internal-State Variables

    NASA Technical Reports Server (NTRS)

    Saleeb, Atef F.; Li, W.; Wilt, Thomas E.

    1997-01-01

    The scope of the work in this presentation focuses on the development of algorithms for the integration of rate dependent constitutive equations. In view of their robustness; i.e., their superior stability and convergence properties for isotropic and anisotropic coupled viscoplastic-damage models, implicit integration schemes have been selected. This is the simplest in its class and is one of the most widely used implicit integrators at present.

  18. Disease Modeling via Large-Scale Network Analysis

    DTIC Science & Technology

    2015-05-20

    SECURITY CLASSIFICATION OF: A central goal of genetics is to learn how the genotype of an organism determines its phenotype. We address the implicit...guarantees for the methods. In the past, we have developed predictive methods general enough to apply to potentially any genetic trait, varying from... genetics is to learn how the genotype of an organism determines its phenotype. We address the implicit problem of predicting the association of genes with

  19. ERP evidence for implicit L2 word stress knowledge in listeners of a fixed-stress language.

    PubMed

    Kóbor, Andrea; Honbolygó, Ferenc; Becker, Angelika B C; Schild, Ulrike; Csépe, Valéria; Friedrich, Claudia K

    2018-06-01

    Languages with contrastive stress, such as English or German, distinguish some words only via the stress status of their syllables, such as "CONtent" and "conTENT" (capitals indicate a stressed syllable). Listeners with a fixed-stress native language, such as Hungarian, have difficulties in explicitly discriminating variation of the stress position in a second language (L2). However, Event-Related Potentials (ERPs) indicate that Hungarian listeners implicitly notice variation from their native fixed-stress pattern. Here we used ERPs to investigate Hungarian listeners' implicit L2 processing. In a cross-modal word fragment priming experiment, we presented spoken stressed and unstressed German word onsets (primes) followed by printed versions of initially stressed and initially unstressed German words (targets). ERPs reflected stress priming exerted by both prime types. This indicates that Hungarian listeners implicitly linked German words with the stress status of the primes. Thus, the formerly described explicit stress discrimination difficulty associated with a fixed-stress native language does not generalize to implicit aspects of L2 word stress processing. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Asymptotic integration algorithms for nonhomogeneous, nonlinear, first order, ordinary differential equations

    NASA Technical Reports Server (NTRS)

    Walker, K. P.; Freed, A. D.

    1991-01-01

    New methods for integrating systems of stiff, nonlinear, first order, ordinary differential equations are developed by casting the differential equations into integral form. Nonlinear recursive relations are obtained that allow the solution to a system of equations at time t plus delta t to be obtained in terms of the solution at time t in explicit and implicit forms. Examples of accuracy obtained with the new technique are given by considering systems of nonlinear, first order equations which arise in the study of unified models of viscoplastic behaviors, the spread of the AIDS virus, and predator-prey populations. In general, the new implicit algorithm is unconditionally stable, and has a Jacobian of smaller dimension than that which is acquired by current implicit methods, such as the Euler backward difference algorithm; yet, it gives superior accuracy. The asymptotic explicit and implicit algorithms are suitable for solutions that are of the growing and decaying exponential kinds, respectively, whilst the implicit Euler-Maclaurin algorithm is superior when the solution oscillates, i.e., when there are regions in which both growing and decaying exponential solutions exist.

  1. 7 CFR 65.115 - Born.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., PORK, LAMB, CHICKEN, GOAT MEAT, PERISHABLE AGRICULTURAL COMMODITIES, MACADAMIA NUTS, PECANS, PEANUTS, AND GINSENG General Provisions Definitions § 65.115 Born. Born in the case of chicken means hatched...

  2. Membrane insertion of fusion peptides from Ebola and Marburg viruses studied by replica-exchange molecular dynamics simulations.

    PubMed

    Olson, Mark A; Lee, Michael S; Yeh, In-Chul

    2017-06-15

    This work presents replica-exchange molecular dynamics simulations of inserting a 16-residue Ebola virus fusion peptide into a membrane bilayer. A computational approach is applied for modeling the peptide at the explicit all-atom level and the membrane-aqueous bilayer by a generalized Born continuum model with a smoothed switching function (GBSW). We provide an assessment of the model calculations in terms of three metrics: (1) the ability to reproduce the NMR structure of the peptide determined in the presence of SDS micelles and comparable structural data on other fusion peptides; (2) determination of the effects of the mutation Trp-8 to Ala and sequence discrimination of the homologous Marburg virus; and (3) calculation of potentials of mean force for estimating the partitioning free energy and their comparison to predictions from the Wimley-White interfacial hydrophobicity scale. We found the GBSW implicit membrane model to produce results of limited accuracy in conformational properties of the peptide when compared to the NMR structure, yet the model resolution is sufficient to determine the effect of sequence differentiation on peptide-membrane integration. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  3. Implicit Racial/Ethnic Bias Among Health Care Professionals and Its Influence on Health Care Outcomes: A Systematic Review.

    PubMed

    Hall, William J; Chapman, Mimi V; Lee, Kent M; Merino, Yesenia M; Thomas, Tainayah W; Payne, B Keith; Eng, Eugenia; Day, Steven H; Coyne-Beasley, Tamera

    2015-12-01

    In the United States, people of color face disparities in access to health care, the quality of care received, and health outcomes. The attitudes and behaviors of health care providers have been identified as one of many factors that contribute to health disparities. Implicit attitudes are thoughts and feelings that often exist outside of conscious awareness, and thus are difficult to consciously acknowledge and control. These attitudes are often automatically activated and can influence human behavior without conscious volition. We investigated the extent to which implicit racial/ethnic bias exists among health care professionals and examined the relationships between health care professionals' implicit attitudes about racial/ethnic groups and health care outcomes. To identify relevant studies, we searched 10 computerized bibliographic databases and used a reference harvesting technique. We assessed eligibility using double independent screening based on a priori inclusion criteria. We included studies if they sampled existing health care providers or those in training to become health care providers, measured and reported results on implicit racial/ethnic bias, and were written in English. We included a total of 15 studies for review and then subjected them to double independent data extraction. Information extracted included the citation, purpose of the study, use of theory, study design, study site and location, sampling strategy, response rate, sample size and characteristics, measurement of relevant variables, analyses performed, and results and findings. We summarized study design characteristics, and categorized and then synthesized substantive findings. Almost all studies used cross-sectional designs, convenience sampling, US participants, and the Implicit Association Test to assess implicit bias. Low to moderate levels of implicit racial/ethnic bias were found among health care professionals in all but 1 study. These implicit bias scores are similar to those in the general population. Levels of implicit bias against Black, Hispanic/Latino/Latina, and dark-skinned people were relatively similar across these groups. Although some associations between implicit bias and health care outcomes were nonsignificant, results also showed that implicit bias was significantly related to patient-provider interactions, treatment decisions, treatment adherence, and patient health outcomes. Implicit attitudes were more often significantly related to patient-provider interactions and health outcomes than treatment processes. Most health care providers appear to have implicit bias in terms of positive attitudes toward Whites and negative attitudes toward people of color. Future studies need to employ more rigorous methods to examine the relationships between implicit bias and health care outcomes. Interventions targeting implicit attitudes among health care professionals are needed because implicit bias may contribute to health disparities for people of color.

  4. Implicit Racial/Ethnic Bias Among Health Care Professionals and Its Influence on Health Care Outcomes: A Systematic Review

    PubMed Central

    Hall, William J.; Lee, Kent M.; Merino, Yesenia M.; Thomas, Tainayah W.; Payne, B. Keith; Eng, Eugenia; Day, Steven H.; Coyne-Beasley, Tamera

    2015-01-01

    Background. In the United States, people of color face disparities in access to health care, the quality of care received, and health outcomes. The attitudes and behaviors of health care providers have been identified as one of many factors that contribute to health disparities. Implicit attitudes are thoughts and feelings that often exist outside of conscious awareness, and thus are difficult to consciously acknowledge and control. These attitudes are often automatically activated and can influence human behavior without conscious volition. Objectives. We investigated the extent to which implicit racial/ethnic bias exists among health care professionals and examined the relationships between health care professionals’ implicit attitudes about racial/ethnic groups and health care outcomes. Search Methods. To identify relevant studies, we searched 10 computerized bibliographic databases and used a reference harvesting technique. Selection Criteria. We assessed eligibility using double independent screening based on a priori inclusion criteria. We included studies if they sampled existing health care providers or those in training to become health care providers, measured and reported results on implicit racial/ethnic bias, and were written in English. Data Collection and Analysis. We included a total of 15 studies for review and then subjected them to double independent data extraction. Information extracted included the citation, purpose of the study, use of theory, study design, study site and location, sampling strategy, response rate, sample size and characteristics, measurement of relevant variables, analyses performed, and results and findings. We summarized study design characteristics, and categorized and then synthesized substantive findings. Main Results. Almost all studies used cross-sectional designs, convenience sampling, US participants, and the Implicit Association Test to assess implicit bias. Low to moderate levels of implicit racial/ethnic bias were found among health care professionals in all but 1 study. These implicit bias scores are similar to those in the general population. Levels of implicit bias against Black, Hispanic/Latino/Latina, and dark-skinned people were relatively similar across these groups. Although some associations between implicit bias and health care outcomes were nonsignificant, results also showed that implicit bias was significantly related to patient–provider interactions, treatment decisions, treatment adherence, and patient health outcomes. Implicit attitudes were more often significantly related to patient–provider interactions and health outcomes than treatment processes. Conclusions. Most health care providers appear to have implicit bias in terms of positive attitudes toward Whites and negative attitudes toward people of color. Future studies need to employ more rigorous methods to examine the relationships between implicit bias and health care outcomes. Interventions targeting implicit attitudes among health care professionals are needed because implicit bias may contribute to health disparities for people of color. PMID:26469668

  5. Virtual Embodiment of White People in a Black Virtual Body Leads to a Sustained Reduction in Their Implicit Racial Bias.

    PubMed

    Banakou, Domna; Hanumanthu, Parasuram D; Slater, Mel

    2016-01-01

    Virtual reality can be used to visually substitute a person's body by a life-sized virtual one. Such embodiment results in a perceptual illusion of body ownership over the virtual body (VB). Previous research has shown that the form of the VB can influence implicit attitudes. In particular, embodying White people in a Black virtual body is associated with an immediate decrease in their implicit racial bias against Black people. We tested whether the reduction in implicit bias lasts for at least 1 week and whether it is enhanced by multiple exposures. Two experiments were carried out with a total of 90 female participants where the virtual body was either Black or White. Participants were required to follow a virtual Tai Chi teacher who was either Asian or European Caucasian. Each participant had 1, 2, or 3 exposures separated by days. Implicit racial bias was measured 1 week before their first exposure and 1 week after their last. The results show that implicit bias decreased more for those with the Black virtual body than the White. There was also some evidence of a general decrease in bias independently of body type for which possible explanations are put forward.

  6. Implicit Particle Filter for Power System State Estimation with Large Scale Renewable Power Integration.

    NASA Astrophysics Data System (ADS)

    Uzunoglu, B.; Hussaini, Y.

    2017-12-01

    Implicit Particle Filter is a sequential Monte Carlo method for data assimilation that guides the particles to the high-probability by an implicit step . It optimizes a nonlinear cost function which can be inherited from legacy assimilation routines . Dynamic state estimation for almost real-time applications in power systems are becomingly increasingly more important with integration of variable wind and solar power generation. New advanced state estimation tools that will replace the old generation state estimation in addition to having a general framework of complexities should be able to address the legacy software and able to integrate the old software in a mathematical framework while allowing the power industry need for a cautious and evolutionary change in comparison to a complete revolutionary approach while addressing nonlinearity and non-normal behaviour. This work implements implicit particle filter as a state estimation tool for the estimation of the states of a power system and presents the first implicit particle filter application study on a power system state estimation. The implicit particle filter is introduced into power systems and the simulations are presented for a three-node benchmark power system . The performance of the filter on the presented problem is analyzed and the results are presented.

  7. Dynamic Exposure to Alcohol Advertising in a Sports Context Influences Implicit Attitudes.

    PubMed

    Zerhouni, Oulmann; Bègue, Laurent; Duke, Aaron A; Flaudias, Valentin

    2016-02-01

    Experimental studies investigating the impact of advertising with ecological stimuli on alcohol-related cognition are scarce. This research investigated the cognitive processes involved in learning implicit attitudes toward alcohol after incidental exposure to alcohol advertisements presented in a dynamic context. We hypothesized that incidental exposure to a specific alcohol brand would lead to heightened positive implicit attitudes toward alcohol due to a mere exposure effect. In total, 108 participants were randomly exposed to dynamic sporting events excerpts with and without advertising for a specific brand of alcohol, after completing self-reported measures of alcohol-related expectancies, alcohol consumption, and attitudes toward sport. Participants then completed a lexical decision task and an affective priming task. We showed that participants were faster to detect brand name after being exposed to advertising during a sports game, and that implicit attitudes of participants toward the brand were more positive after they were exposed to advertising, even when alcohol usage patterns were controlled for. Incidental exposure to alcohol sponsorship in sport events impacts implicit attitudes toward the advertised brand and alcohol in general. The effect of incidental advertising on implicit attitudes is also likely to be due to a mere exposure effect. However, further studies should address this point specifically. Copyright © 2016 by the Research Society on Alcoholism.

  8. Virtual Embodiment of White People in a Black Virtual Body Leads to a Sustained Reduction in Their Implicit Racial Bias

    PubMed Central

    Banakou, Domna; Hanumanthu, Parasuram D.; Slater, Mel

    2016-01-01

    Virtual reality can be used to visually substitute a person's body by a life-sized virtual one. Such embodiment results in a perceptual illusion of body ownership over the virtual body (VB). Previous research has shown that the form of the VB can influence implicit attitudes. In particular, embodying White people in a Black virtual body is associated with an immediate decrease in their implicit racial bias against Black people. We tested whether the reduction in implicit bias lasts for at least 1 week and whether it is enhanced by multiple exposures. Two experiments were carried out with a total of 90 female participants where the virtual body was either Black or White. Participants were required to follow a virtual Tai Chi teacher who was either Asian or European Caucasian. Each participant had 1, 2, or 3 exposures separated by days. Implicit racial bias was measured 1 week before their first exposure and 1 week after their last. The results show that implicit bias decreased more for those with the Black virtual body than the White. There was also some evidence of a general decrease in bias independently of body type for which possible explanations are put forward. PMID:27965555

  9. Understanding Emotions in Frontotemporal Dementia: The Explicit and Implicit Emotional Cue Mismatch.

    PubMed

    Balconi, Michela; Cotelli, Maria; Brambilla, Michela; Manenti, Rosa; Cosseddu, Maura; Premi, Enrico; Gasparotti, Roberto; Zanetti, Orazio; Padovani, Alessandro; Borroni, Barbara

    2015-01-01

    Previous studies have reported significant deficits in emotion recognition among individuals along the frontotemporal dementia (FTD) spectrum. The basis of emotional impairment is still poorly understood and explicit (emotion appraisal) and implicit (autonomic system activity) responses have not been carefully evaluated. We investigated explicit evaluation of emotions by testing valence and arousal using self-report measures and we also assessed automatic responses to emotional cues, using autonomic measures (skin conductance response and heart rate). 16 behavioral variant FTD and 12 agrammatic variants of primary progressive aphasia patients were included. The performance of these patients was compared to a group of 14 patients with Alzheimer's disease and 20 healthy controls. Each subject was required to observe and evaluate affective pictures while autonomic parameters were recorded. FTD patients preserved a functional general competency in terms of valence (correct positive versus negative attribution) and arousal (correct dichotomy between high versus low arousal category) distinction. These patients showed significant changes in autonomic implicit response compared to the other groups. The mismatch between explicit and implicit responsiveness to emotional cues was found both in behavioral variant FTD and in agrammatic variants of primary progressive aphasia. Emotional responsiveness was related to the severity of behavioral abnormalities as measured by the Frontal Behavioral Inventory and associated with atrophy of the left putamen. The present findings indicate that FTD patients are able to explicitly "appraise" the emotion, but they cannot implicitly "feel" the emotion. This mismatch between the two levels may help explain the general emotional behavior impairment found in these patients.

  10. Adjoint-Based Uncertainty Quantification with MCNP

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

    Seifried, Jeffrey E.

    2011-09-01

    This work serves to quantify the instantaneous uncertainties in neutron transport simulations born from nuclear data and statistical counting uncertainties. Perturbation and adjoint theories are used to derive implicit sensitivity expressions. These expressions are transformed into forms that are convenient for construction with MCNP6, creating the ability to perform adjoint-based uncertainty quantification with MCNP6. These new tools are exercised on the depleted-uranium hybrid LIFE blanket, quantifying its sensitivities and uncertainties to important figures of merit. Overall, these uncertainty estimates are small (< 2%). Having quantified the sensitivities and uncertainties, physical understanding of the system is gained and some confidence inmore » the simulation is acquired.« less

  11. Generalized Born-Oppenheimer treatment of Jahn-Teller systems in Hilbert spaces of arbitrary dimension: theory and application to a three-state model potential.

    PubMed

    Varandas, A J C; Sarkar, B

    2011-05-14

    Generalized Born-Oppenheimer equations including the geometrical phase effect are derived for three- and four-fold electronic manifolds in Jahn-Teller systems near the degeneracy seam. The method is readily extendable to N-fold systems of arbitrary dimension. An application is reported for a model threefold system, and the results are compared with Born-Oppenheimer (geometrical phase ignored), extended Born-Oppenheimer, and coupled three-state calculations. The theory shows unprecedented simplicity while depicting all features of more elaborated ones.

  12. Engine-induced structural-borne noise in a general aviation aircraft

    NASA Technical Reports Server (NTRS)

    Unruh, J. F.; Scheidt, D. C.; Pomerening, D. J.

    1979-01-01

    Structural borne interior noise in a single engine general aviation aircraft was studied to determine the importance of engine induced structural borne noise and to determine the necessary modeling requirements for the prediction of structural borne interior noise. Engine attached/detached ground test data show that engine induced structural borne noise is a primary interior noise source for the single engine test aircraft, cabin noise is highly influenced by responses at the propeller tone, and cabin acoustic resonances can influence overall noise levels. Results from structural and acoustic finite element coupled models of the test aircraft show that wall flexibility has a strong influence on fundamental cabin acoustic resonances, the lightweight fuselage structure has a high modal density, and finite element analysis procedures are appropriate for the prediction of structural borne noise.

  13. Spatializing Emotion: No Evidence for a Domain-General Magnitude System.

    PubMed

    Pitt, Benjamin; Casasanto, Daniel

    2017-11-22

    People implicitly associate different emotions with different locations in left-right space. Which aspects of emotion do they spatialize, and why? Across many studies people spatialize emotional valence, mapping positive emotions onto their dominant side of space and negative emotions onto their non-dominant side, consistent with theories of metaphorical mental representation. Yet other results suggest a conflicting mapping of emotional intensity (a.k.a., emotional magnitude), according to which people associate more intense emotions with the right and less intense emotions with the left - regardless of their valence; this pattern has been interpreted as support for a domain-general system for representing magnitudes. To resolve the apparent contradiction between these mappings, we first tested whether people implicitly map either valence or intensity onto left-right space, depending on which dimension of emotion they attend to (Experiments 1a, b). When asked to judge emotional valence, participants showed the predicted valence mapping. However, when asked to judge emotional intensity, participants showed no systematic intensity mapping. We then tested an alternative explanation of findings previously interpreted as evidence for an intensity mapping (Experiments 2a, b). These results suggest that previous findings may reflect a left-right mapping of spatial magnitude (i.e., the size of a salient feature of the stimuli) rather than emotion. People implicitly spatialize emotional valence, but, at present, there is no clear evidence for an implicit lateral mapping of emotional intensity. These findings support metaphor theory and challenge the proposal that mental magnitudes are represented by a domain-general metric that extends to the domain of emotion. Copyright © 2017 Cognitive Science Society, Inc.

  14. Surprise! Infants Consider Possible Bases of Generalization for a Single Input Example

    ERIC Educational Resources Information Center

    Gerken, LouAnn; Dawson, Colin; Chatila, Razanne; Tenenbaum, Josh

    2015-01-01

    Infants have been shown to generalize from a small number of input examples. However, existing studies allow two possible means of generalization. One is via a process of noting similarities shared by several examples. Alternatively, generalization may reflect an implicit desire to explain the input. The latter view suggests that generalization…

  15. Diagonalization of complex symmetric matrices: Generalized Householder reflections, iterative deflation and implicit shifts

    NASA Astrophysics Data System (ADS)

    Noble, J. H.; Lubasch, M.; Stevens, J.; Jentschura, U. D.

    2017-12-01

    We describe a matrix diagonalization algorithm for complex symmetric (not Hermitian) matrices, A ̲ =A̲T, which is based on a two-step algorithm involving generalized Householder reflections based on the indefinite inner product 〈 u ̲ , v ̲ 〉 ∗ =∑iuivi. This inner product is linear in both arguments and avoids complex conjugation. The complex symmetric input matrix is transformed to tridiagonal form using generalized Householder transformations (first step). An iterative, generalized QL decomposition of the tridiagonal matrix employing an implicit shift converges toward diagonal form (second step). The QL algorithm employs iterative deflation techniques when a machine-precision zero is encountered "prematurely" on the super-/sub-diagonal. The algorithm allows for a reliable and computationally efficient computation of resonance and antiresonance energies which emerge from complex-scaled Hamiltonians, and for the numerical determination of the real energy eigenvalues of pseudo-Hermitian and PT-symmetric Hamilton matrices. Numerical reference values are provided.

  16. Attempted Training of Alcohol Approach and Drinking Identity Associations in US Undergraduate Drinkers: Null Results from Two Studies

    PubMed Central

    Lindgren, Kristen P.; Wiers, Reinout W.; Teachman, Bethany A.; Gasser, Melissa L.; Westgate, Erin C.; Cousijn, Janna; Enkema, Matthew C.; Neighbors, Clayton

    2015-01-01

    There is preliminary evidence that approach avoid training can shift implicit alcohol associations and improve treatment outcomes. We sought to replicate and extend those findings in US undergraduate social drinkers (Study 1) and at-risk drinkers (Study 2). Three adaptations of the approach avoid task (AAT) were tested. The first adaptation – the approach avoid training – was a replication and targeted implicit alcohol approach associations. The remaining two adaptations – the general identity and personalized identity trainings – targeted implicit drinking identity associations, which are robust predictors of hazardous drinking in US undergraduates. Study 1 included 300 undergraduate social drinkers. They were randomly assigned to real or sham training conditions for one of the three training adaptations, and completed two training sessions, spaced one week apart. Study 2 included 288 undergraduates at risk for alcohol use disorders. The same training procedures were used, but the two training sessions occurred within a single week. Results were not as expected. Across both studies, the approach avoid training yielded no evidence of training effects on implicit alcohol associations or alcohol outcomes. The general identity training also yielded no evidence of training effects on implicit alcohol associations or alcohol outcomes with one exception; individuals who completed real training demonstrated no changes in drinking refusal self-efficacy whereas individuals who completed sham training had reductions in self-efficacy. Finally, across both studies, the personalized identity training yielded no evidence of training effects on implicit alcohol associations or alcohol outcomes. Despite having relatively large samples and using a well-validated training task, study results indicated all three training adaptations were ineffective at this dose in US undergraduates. These findings are important because training studies are costly and labor-intensive. Future research may benefit from focusing on more severe populations, pairing training with other interventions, increasing training dose, and increasing gamification of training tasks. PMID:26241316

  17. Born approximation in linear-time invariant system

    NASA Astrophysics Data System (ADS)

    Gumjudpai, Burin

    2017-09-01

    An alternative way of finding the LTI’s solution with the Born approximation, is investigated. We use Born approximation in the LTI and in the transformed LTI in form of Helmholtz equation. General solution are considered as infinite series or Feynman graph. Slow-roll approximation are explored. Transforming the LTI system into Helmholtz equation, approximated general solution can be found for any given forms of force with its initial value.

  18. Role of Spontaneous Brain Activity in Explicit and Implicit Aspects of Cognitive Flexibility under Socially Conflicting Situations: A Resting-state fMRI Study using Fractional Amplitude of Low-frequency Fluctuations.

    PubMed

    Fujino, Junya; Tei, Shisei; Jankowski, Kathryn F; Kawada, Ryosaku; Murai, Toshiya; Takahashi, Hidehiko

    2017-12-26

    We are constantly exposed to socially conflicting situations in everyday life, and cognitive flexibility is essential for adaptively coping with such difficulties. Flexible goal choice and pursuit are not exclusively conscious, and therefore cognitive flexibility involves both explicit and implicit forms of processing. However, it is unclear how individual differences in explicit and implicit aspects of flexibility are associated with neural activity in a resting state. Here, we measured intrinsic fractional amplitude of low-frequency fluctuations (fALFF) by resting-state functional magnetic resonance imaging (RS-fMRI) as an indicator of regional brain spontaneous activity, together with explicit and implicit aspects of cognitive flexibility using the Cognitive Flexibility Scale (CFS) and Implicit Association Test (IAT). Consistent with the dual processing theory, there was a strong association between explicit aspects of flexibility (CFS score) and "rationalism" thinking style and between implicit aspects (IAT effect) and "experientialism." The level of explicit flexibility was also correlated with fALFF values in the left lateral prefrontal cortex, whereas the level of implicit flexibility was correlated with fALFF values in the right cerebellum. Furthermore, the fALFF values in both regions predicted individual preference for flexible decision-making strategy in a vignettes simulation task. These results add to our understanding of the neural mechanisms underlying flexible decision-making for solving social conflicts. More generally, our findings highlight the utility of RS-fMRI combined with both explicit and implicit psychometric measures for better understanding individual differences in social cognition. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  19. A General Instance-Based Learning Framework for Studying Intuitive Decision-Making in a Cognitive Architecture (Open Access, Publisher’s Version)

    DTIC Science & Technology

    2014-06-19

    decision theory (Berger, 1985), and quantum probability theory (Busemeyer, Pothos, Franco, & Trueblood, 2011). Similarly, explanations in the 1 rch in...trengths of associations) are consciously inaccessible and con- titute the implicit knowledge of the model (Gonzalez & Lebiere, 005; Lebiere, Wallach...in memory (Lebiere et al., 2013). It is important to note hat this wholly implicit process is not consciously available to the odel. The second level

  20. The picture superiority effect in conceptual implicit memory: a conceptual distinctiveness hypothesis.

    PubMed

    Hamilton, Maryellen; Geraci, Lisa

    2006-01-01

    According to leading theories, the picture superiority effect is driven by conceptual processing, yet this effect has been difficult to obtain using conceptual implicit memory tests. We hypothesized that the picture superiority effect results from conceptual processing of a picture's distinctive features rather than a picture's semantic features. To test this hypothesis, we used 2 conceptual implicit general knowledge tests; one cued conceptually distinctive features (e.g., "What animal has large eyes?") and the other cued semantic features (e.g., "What animal is the figurehead of Tootsie Roll?"). Results showed a picture superiority effect only on the conceptual test using distinctive cues, supporting our hypothesis that this effect is mediated by conceptual processing of a picture's distinctive features.

  1. Does anesthetic regimen influence implicit memory during general anesthesia?

    PubMed

    Lequeux, Pierre-Yves; Hecquet, Fidelie; Bredas, Philippe

    2014-11-01

    Implicit learning of intraoperative auditory stimuli during general anesthesia is very difficult to quantify but may require the presence of noxious stimulation. We hypothesized that an anesthetic regimen with a low dose of opioid would enhance implicit memory, while a regimen with a high dose of opioid would not. One hundred-twenty patients were randomized into 3 groups. All patients were anesthetized with a target-controlled infusion of propofol and remifentanil, targeting a Bispectral Index (BIS) value of 50. The remifentanil effect-site concentration (in ng/mL) was always double that of propofol (in μg/mL) in the first group and half of that in the second group. Patients in these 2 groups were played a list of 20 words via headphones during surgery. The third group served as control for memory tests and was not played any word during anesthesia. BIS was recorded during word presentation. No statistical difference was found among the 3 groups regarding 3 different memory tests although 67.5% [50.7%; 80.9%] of the patients of the high-opioid group and 72.5% [55.9%; 84.9%] of the low-opioid group had at least 1 episode of BIS >60. We could not demonstrate the presence of implicit or explicit memorization under propofol-remifentanil anesthesia either with a low- or a high-dose opioid anesthetic regimen.

  2. Nonuniform grid implicit spatial finite difference method for acoustic wave modeling in tilted transversely isotropic media

    NASA Astrophysics Data System (ADS)

    Chu, Chunlei; Stoffa, Paul L.

    2012-01-01

    Discrete earth models are commonly represented by uniform structured grids. In order to ensure accurate numerical description of all wave components propagating through these uniform grids, the grid size must be determined by the slowest velocity of the entire model. Consequently, high velocity areas are always oversampled, which inevitably increases the computational cost. A practical solution to this problem is to use nonuniform grids. We propose a nonuniform grid implicit spatial finite difference method which utilizes nonuniform grids to obtain high efficiency and relies on implicit operators to achieve high accuracy. We present a simple way of deriving implicit finite difference operators of arbitrary stencil widths on general nonuniform grids for the first and second derivatives and, as a demonstration example, apply these operators to the pseudo-acoustic wave equation in tilted transversely isotropic (TTI) media. We propose an efficient gridding algorithm that can be used to convert uniformly sampled models onto vertically nonuniform grids. We use a 2D TTI salt model to demonstrate its effectiveness and show that the nonuniform grid implicit spatial finite difference method can produce highly accurate seismic modeling results with enhanced efficiency, compared to uniform grid explicit finite difference implementations.

  3. Implicit theories and ability emotional intelligence

    PubMed Central

    Cabello, Rosario; Fernández-Berrocal, Pablo

    2015-01-01

    Previous research has shown that people differ in their implicit theories about the essential characteristics of intelligence and emotions. Some people believe these characteristics to be predetermined and immutable (entity theorists), whereas others believe that these characteristics can be changed through learning and behavior training (incremental theorists). The present study provides evidence that in healthy adults (N = 688), implicit beliefs about emotions and emotional intelligence (EI) may influence performance on the ability-based Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT). Adults in our sample with incremental theories about emotions and EI scored higher on the MSCEIT than entity theorists, with implicit theories about EI showing a stronger relationship to scores than theories about emotions. Although our participants perceived both emotion and EI as malleable, they viewed emotions as more malleable than EI. Women and young adults in general were more likely to be incremental theorists than men and older adults. Furthermore, we found that emotion and EI theories mediated the relationship of gender and age with ability EI. Our findings suggest that people’s implicit theories about EI may influence their emotional abilities, which may have important consequences for personal and professional EI training. PMID:26052309

  4. An Implicit Measure of Associations with Mental Illness versus Physical Illness: Response Latency Decomposition and Stimuli Differential Functioning in Relation to IAT Order of Associative Conditions and Accuracy

    PubMed Central

    Mannarini, Stefania; Boffo, Marilisa

    2014-01-01

    The present study aimed at the definition of a latent measurement dimension underlying an implicit measure of automatic associations between the concept of mental illness and the psychosocial and biogenetic causal explanatory attributes. To this end, an Implicit Association Test (IAT) assessing the association between the Mental Illness and Physical Illness target categories to the Psychological and Biologic attribute categories, representative of the causal explanation domains, was developed. The IAT presented 22 stimuli (words and pictures) to be categorized into the four categories. After 360 university students completed the IAT, a Many-Facet Rasch Measurement (MFRM) modelling approach was applied. The model specified a person latency parameter and a stimulus latency parameter. Two additional parameters were introduced to denote the order of presentation of the task associative conditions and the general response accuracy. Beyond the overall definition of the latent measurement dimension, the MFRM was also applied to disentangle the effect of the task block order and the general response accuracy on the stimuli response latency. Further, the MFRM allowed detecting any differential functioning of each stimulus in relation to both block ordering and accuracy. The results evidenced: a) the existence of a latency measurement dimension underlying the Mental Illness versus Physical Illness - Implicit Association Test; b) significant effects of block order and accuracy on the overall latency; c) a differential functioning of specific stimuli. The results of the present study can contribute to a better understanding of the functioning of an implicit measure of semantic associations with mental illness and give a first blueprint for the examination of relevant issues in the development of an IAT. PMID:25000406

  5. An implicit measure of associations with mental illness versus physical illness: response latency decomposition and stimuli differential functioning in relation to IAT order of associative conditions and accuracy.

    PubMed

    Mannarini, Stefania; Boffo, Marilisa

    2014-01-01

    The present study aimed at the definition of a latent measurement dimension underlying an implicit measure of automatic associations between the concept of mental illness and the psychosocial and biogenetic causal explanatory attributes. To this end, an Implicit Association Test (IAT) assessing the association between the Mental Illness and Physical Illness target categories to the Psychological and Biologic attribute categories, representative of the causal explanation domains, was developed. The IAT presented 22 stimuli (words and pictures) to be categorized into the four categories. After 360 university students completed the IAT, a Many-Facet Rasch Measurement (MFRM) modelling approach was applied. The model specified a person latency parameter and a stimulus latency parameter. Two additional parameters were introduced to denote the order of presentation of the task associative conditions and the general response accuracy. Beyond the overall definition of the latent measurement dimension, the MFRM was also applied to disentangle the effect of the task block order and the general response accuracy on the stimuli response latency. Further, the MFRM allowed detecting any differential functioning of each stimulus in relation to both block ordering and accuracy. The results evidenced: a) the existence of a latency measurement dimension underlying the Mental Illness versus Physical Illness - Implicit Association Test; b) significant effects of block order and accuracy on the overall latency; c) a differential functioning of specific stimuli. The results of the present study can contribute to a better understanding of the functioning of an implicit measure of semantic associations with mental illness and give a first blueprint for the examination of relevant issues in the development of an IAT.

  6. [Effect of divided attention on explicit and implicit aspects of recall].

    PubMed

    Wippich, W; Schmitt, R; Mecklenbräuker, S

    1989-01-01

    If subjects have to form word images before spelling a word from the image, results of a repetition of the spelling test reveal a reliable priming effect: Old words can be spelled faster than comparable control words, reflecting a form of implicit memory. We investigated whether this kind of repetition priming remains stable under conditions of divided attention in the study phase. The subjects had to spell meaningful words, meaningless non-words, and non-words that were meaningful with a backward spelling direction (troper, for example). In the testing stage, recognition judgments as a form of explicit memory were required, too. Divided attention in the study phase had a negative effect on explicit memory, as revealed by performance on the recognition task, but had little effect on implicit memory, as revealed by performance on the repetition of the spelling test. A further dissociation between implicit and explicit memory showed up as meaningful words were recognized much better than non-words, whereas implicit memory was uninfluenced by the meaningfulness variable. The disadvantage of backward spellings was not reduced with non-words (like troper) spelled backwards. Finally, we analyzed the relations between spelling times and recognition judgments and found a pattern of dependency for non-words only. Generally, the results are discussed within processing-oriented approaches to implicit memory with a special emphasis on controversial findings concerning the role of attention in different expressions of memory.

  7. Cohort Differences in Cognitive Aging in the Longitudinal Aging Study Amsterdam.

    PubMed

    Brailean, Anamaria; Huisman, Martijn; Prince, Martin; Prina, A Matthew; Deeg, Dorly J H; Comijs, Hannie

    2016-09-30

    This study aims to examine cohort differences in cognitive performance and rates of change in episodic memory, processing speed, inductive reasoning, and general cognitive performance and to investigate whether these cohort effects may be accounted for by education attainment. The first cohort (N = 705) was born between 1920 and 1930, whereas the second cohort (N = 646) was born between 1931 and 1941. Both birth cohorts were aged 65 to 75 years at baseline and were followed up 3 and 6 years later. Data were analyzed using linear mixed models. The later born cohort had better general cognitive performance, inductive reasoning, and processing speed at baseline, but cohort differences in inductive reasoning and general cognitive performance disappeared after adjusting for education. The later born cohort showed steeper decline in processing speed. Memory decline was steeper in the earlier born cohort but only from Time 1 to Time 3 when the same memory test was administered. Education did not account for cohort differences in cognitive decline. The later born cohort showed better initial performance in certain cognitive abilities, but no better preservation of cognitive abilities overtime compared with the earlier born cohort. These findings carry implications for healthy cognitive aging. © The Author 2016. Published by Oxford University Press on behalf of The Gerontological Society of America.

  8. How to Modify (Implicit) Evaluations of Fear-Related Stimuli: Effects of Feature-Specific Attention Allocation

    PubMed Central

    Vanaelst, Jolien; Spruyt, Adriaan; De Houwer, Jan

    2016-01-01

    We demonstrate that feature-specific attention allocation influences the way in which repeated exposure modulates implicit and explicit evaluations toward fear-related stimuli. During an exposure procedure, participants were encouraged to assign selective attention either to the evaluative meaning (i.e., Evaluative Condition) or a non-evaluative, semantic feature (i.e., Semantic Condition) of fear-related stimuli. The influence of the exposure procedure was captured by means of a measure of implicit evaluation, explicit evaluative ratings, and a measure of automatic approach/avoidance tendencies. As predicted, the implicit measure of evaluation revealed a reduced expression of evaluations in the Semantic Condition as compared to the Evaluative Condition. Moreover, this effect generalized toward novel objects that were never presented during the exposure procedure. The explicit measure of evaluation mimicked this effect, although it failed to reach conventional levels of statistical significance. No effects were found in terms of automatic approach/avoidance tendencies. Potential implications for the treatment of anxiety disorders are discussed. PMID:27242626

  9. Implicit continuum mechanics approach to heat conduction in granular materials

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

    Massoudi, M.; Mehrabadi, M.

    In this paper, we derive a properly frame-invariant implicit constitutive relationship for the heat flux vector for a granular medium (or a density-gradient-type fluid). The heat flux vector is commonly modeled by Fourier’s law of heat conduction, and for complex materials such as nonlinear fluids, porous media, or granular materials, the coefficient of thermal conductivity is generalized by assuming that it would depend on a host of material and kinematic parameters such as temperature, shear rate, porosity, concentration, etc. In this paper, we extend the approach of Massoudi [Massoudi, M. Math. Methods Appl. Sci. 2006, 29, 1585; Massoudi, M. Math.more » Methods Appl. Sci. 2006, 29, 1599], who provided explicit constitutive relations for the heat flux vector for flowing granular materials; in order to do so, we use the implicit scheme suggested by Fox [Fox, N. Int. J. Eng. Sci. 1969, 7, 437], who obtained implicit relations in thermoelasticity.« less

  10. Implicit theories of a desire for fame.

    PubMed

    Maltby, John; Day, Liz; Giles, David; Gillett, Raphael; Quick, Marianne; Langcaster-James, Honey; Linley, P Alex

    2008-05-01

    The aim of the present studies was to generate implicit theories of a desire for fame among the general population. In Study 1, we were able to develop a nine-factor analytic model of conceptions of the desire to be famous that initially comprised nine separate factors; ambition, meaning derived through comparison with others, psychologically vulnerable, attention seeking, conceitedness, social access, altruistic, positive affect, and glamour. Analysis that sought to examine replicability among these factors suggested that three factors (altruistic, positive affect, and glamour) neither display factor congruence nor display adequate internal reliability. A second study examined the validity of these factors in predicting profiles of individuals who may desire fame. The findings from this study suggested that two of the nine factors (positive affect and altruism) could not be considered strong factors within the model. Overall, the findings suggest that implicit theories of a desire for fame comprise six factors. The discussion focuses on how an implicit model of a desire for fame might progress into formal theories of a desire for fame.

  11. How to Modify (Implicit) Evaluations of Fear-Related Stimuli: Effects of Feature-Specific Attention Allocation.

    PubMed

    Vanaelst, Jolien; Spruyt, Adriaan; De Houwer, Jan

    2016-01-01

    We demonstrate that feature-specific attention allocation influences the way in which repeated exposure modulates implicit and explicit evaluations toward fear-related stimuli. During an exposure procedure, participants were encouraged to assign selective attention either to the evaluative meaning (i.e., Evaluative Condition) or a non-evaluative, semantic feature (i.e., Semantic Condition) of fear-related stimuli. The influence of the exposure procedure was captured by means of a measure of implicit evaluation, explicit evaluative ratings, and a measure of automatic approach/avoidance tendencies. As predicted, the implicit measure of evaluation revealed a reduced expression of evaluations in the Semantic Condition as compared to the Evaluative Condition. Moreover, this effect generalized toward novel objects that were never presented during the exposure procedure. The explicit measure of evaluation mimicked this effect, although it failed to reach conventional levels of statistical significance. No effects were found in terms of automatic approach/avoidance tendencies. Potential implications for the treatment of anxiety disorders are discussed.

  12. Lovelock gravities from Born-Infeld gravity theory

    NASA Astrophysics Data System (ADS)

    Concha, P. K.; Merino, N.; Rodríguez, E. K.

    2017-02-01

    We present a Born-Infeld gravity theory based on generalizations of Maxwell symmetries denoted as Cm. We analyze different configuration limits allowing to recover diverse Lovelock gravity actions in six dimensions. Further, the generalization to higher even dimensions is also considered.

  13. Attention and implicit memory in the category-verification and lexical decision tasks.

    PubMed

    Mulligan, Neil W; Peterson, Daniel

    2008-05-01

    Prior research on implicit memory appeared to support 3 generalizations: Conceptual tests are affected by divided attention, perceptual tasks are affected by certain divided-attention manipulations, and all types of priming are affected by selective attention. These generalizations are challenged in experiments using the implicit tests of category verification and lexical decision. First, both tasks were unaffected by divided-attention tasks known to impact other priming tasks. Second, both tasks were unaffected by a manipulation of selective attention in which colored words were either named or their colors identified. Thus, category verification, unlike other conceptual tasks, appears unaffected by divided attention, and some selective-attention tasks, and lexical decision, unlike other perceptual tasks, appears unaffected by a difficult divided-attention task and some selective-attention tasks. Finally, both tasks were affected by a selective-attention task in which attention was manipulated across objects (rather than within objects), indicating some susceptibility to selective attention. The results contradict an analysis on the basis of the conceptual-perceptual distinction and other more specific hypotheses but are consistent with the distinction between production and identification priming.

  14. Diagonally Implicit Runge-Kutta Methods for Ordinary Differential Equations. A Review

    NASA Technical Reports Server (NTRS)

    Kennedy, Christopher A.; Carpenter, Mark H.

    2016-01-01

    A review of diagonally implicit Runge-Kutta (DIRK) methods applied to rst-order ordinary di erential equations (ODEs) is undertaken. The goal of this review is to summarize the characteristics, assess the potential, and then design several nearly optimal, general purpose, DIRK-type methods. Over 20 important aspects of DIRKtype methods are reviewed. A design study is then conducted on DIRK-type methods having from two to seven implicit stages. From this, 15 schemes are selected for general purpose application. Testing of the 15 chosen methods is done on three singular perturbation problems. Based on the review of method characteristics, these methods focus on having a stage order of two, sti accuracy, L-stability, high quality embedded and dense-output methods, small magnitudes of the algebraic stability matrix eigenvalues, small values of aii, and small or vanishing values of the internal stability function for large eigenvalues of the Jacobian. Among the 15 new methods, ESDIRK4(3)6L[2]SA is recommended as a good default method for solving sti problems at moderate error tolerances.

  15. The Consolidation of Implicit Sequence Memory in Obstructive Sleep Apnea

    PubMed Central

    Malecek, Nick

    2014-01-01

    Obstructive Sleep Apnea (OSA) Syndrome is a relatively frequent sleep disorder characterized by disrupted sleep patterns. It is a well-established fact that sleep has beneficial effect on memory consolidation by enhancing neural plasticity. Implicit sequence learning is a prominent component of skill learning. However, the formation and consolidation of this fundamental learning mechanism remains poorly understood in OSA. In the present study we examined the consolidation of different aspects of implicit sequence learning in patients with OSA. We used the Alternating Serial Reaction Time task to measure general skill learning and sequence-specific learning. There were two sessions: a learning phase and a testing phase, separated by a 10-hour offline period with sleep. Our data showed differences in offline changes of general skill learning between the OSA and control group. The control group demonstrated offline improvement from evening to morning, while the OSA group did not. In contrast, we did not observe differences between the groups in offline changes in sequence-specific learning. Our findings suggest that disrupted sleep in OSA differently affects neural circuits involved in the consolidation of sequence learning. PMID:25329462

  16. Cue-induced activation of implicit affective associations with heroin use in abstinent heroin abusers.

    PubMed

    Chen, Jianyong; Wang, Xuan; Zhang, Meng; Zhang, Feng; Shen, Mowei

    2015-06-01

    While drug-related contexts have been shown to influence drug users' implicit and explicit drug-related cognitions, this has been minimally explored in heroin abusers. This study examined the effect of heroin-related cue exposure on implicit and explicit valence and arousal-sedation associations with heroin use for abstinent heroin abusers. In Experiment 1, 39 male abstinent heroin abusers were exposed to heroin-related words and reported cravings before and after cue exposure. They subsequently performed two Extrinsic Affective Simon Tasks (EASTs), which were used to assess implicit valence and arousal-sedation associations with heroin use. Thirty-six male abstinent heroin abusers (controls) only performed the two EASTs. All participants completed measures of explicit expectancy regarding heroin use. In Experiment 2, twenty-eight newly recruited abstinent heroin abusers were exposed to heroin-related pictures, and completed the same implicit and explicit measures used in Experiment 1. A non-significant increase in craving after cue exposure was observed. While participants exposed to heroin-related words or pictures exhibited more positive implicit heroin use associations (relative to negative associations), and such trend was not observed in controls, this difference was not significant across groups. Participants still indicated negative explicit associations with heroin use after cue exposure. Exposure to cues significantly accelerated arousal and sedation responses. Whether cue exposure could change self-reported craving requires further study in abstinent heroin abusers. The exclusively male sample limits generalization of the results. The present findings extend the evidence on whether implicit and explicit heroin-related cognitions are susceptible to context. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Implicit treatment of diffusion terms in lower-upper algorithms

    NASA Technical Reports Server (NTRS)

    Shih, T. I.-P.; Steinthorsson, E.; Chyu, W. J.

    1993-01-01

    A method is presented which allows diffusion terms to be treated implicitly in the lower-upper (LU) algorithm (which is a commonly used method for solving 'compressible' Euler and Navier-Stokes equations) so that the algorithm's good stability properties will not be impaired. The new method generalizes the concept of LU factorization from that associated with the sign of eigenvalues to that associated with backward- and forward-difference operators without regard to eigenvalues. The method is verified in a turbulent boundary layer study.

  18. The attractiveness-positivity link: Let's contextualize it.

    PubMed

    Mello, Joana; Garcia-Marques, Teresa

    2018-02-27

    The statement "what is beautiful is good" reflects a persuasive heuristic that may be supported either by a general association of attractiveness with positivity or by a specific association with the perceived credibility of an attractive source. In one study (N = 58), we approach this question using an explicit and an implicit measure (Stroop Task) to assess whether attractiveness is more likely associated with valenced words when these are related (vs. unrelated) to credibility. Results show that this effect occurs but only for the implicit measure. When the word-face associations were made at an explicit level, we found a general association between positivity and attractiveness, unrestricted to the dimension of credibility. We discuss how these results inform about attractiveness as a shortcut to judgments of validity.

  19. Development and Verification of the Charring, Ablating Thermal Protection Implicit System Simulator

    NASA Technical Reports Server (NTRS)

    Amar, Adam J.; Calvert, Nathan; Kirk, Benjamin S.

    2011-01-01

    The development and verification of the Charring Ablating Thermal Protection Implicit System Solver (CATPISS) is presented. This work concentrates on the derivation and verification of the stationary grid terms in the equations that govern three-dimensional heat and mass transfer for charring thermal protection systems including pyrolysis gas flow through the porous char layer. The governing equations are discretized according to the Galerkin finite element method (FEM) with first and second order fully implicit time integrators. The governing equations are fully coupled and are solved in parallel via Newton s method, while the linear system is solved via the Generalized Minimum Residual method (GMRES). Verification results from exact solutions and Method of Manufactured Solutions (MMS) are presented to show spatial and temporal orders of accuracy as well as nonlinear convergence rates.

  20. Implicit and Multigrid Method for Ideal Multigrid Convergence: Direct Numerical Simulation of Separated Flow Around NACA 0012 Airfoil

    NASA Technical Reports Server (NTRS)

    Liu, Chao-Qun; Shan, H.; Jiang, L.

    1999-01-01

    Numerical investigation of flow separation over a NACA 0012 airfoil at large angles of attack has been carried out. The numerical calculation is performed by solving the full Navier-Stokes equations in generalized curvilinear coordinates. The second-order LU-SGS implicit scheme is applied for time integration. This scheme requires no tridiagonal inversion and is capable of being completely vectorized, provided the corresponding Jacobian matrices are properly selected. A fourth-order centered compact scheme is used for spatial derivatives. In order to reduce numerical oscillation, a sixth-order implicit filter is employed. Non-reflecting boundary conditions are imposed at the far-field and outlet boundaries to avoid possible non-physical wave reflection. Complex flow separation and vortex shedding phenomenon have been observed and discussed.

  1. A time-implicit numerical method and benchmarks for the relativistic Vlasov–Ampere equations

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

    Carrie, Michael; Shadwick, B. A.

    2016-01-04

    Here, we present a time-implicit numerical method to solve the relativistic Vlasov–Ampere system of equations on a two dimensional phase space grid. The time-splitting algorithm we use allows the generalization of the work presented here to higher dimensions keeping the linear aspect of the resulting discrete set of equations. The implicit method is benchmarked against linear theory results for the relativistic Landau damping for which analytical expressions using the Maxwell-Juttner distribution function are derived. We note that, independently from the shape of the distribution function, the relativistic treatment features collective behaviors that do not exist in the non relativistic case.more » The numerical study of the relativistic two-stream instability completes the set of benchmarking tests.« less

  2. A time-implicit numerical method and benchmarks for the relativistic Vlasov–Ampere equations

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

    Carrié, Michael, E-mail: mcarrie2@unl.edu; Shadwick, B. A., E-mail: shadwick@mailaps.org

    2016-01-15

    We present a time-implicit numerical method to solve the relativistic Vlasov–Ampere system of equations on a two dimensional phase space grid. The time-splitting algorithm we use allows the generalization of the work presented here to higher dimensions keeping the linear aspect of the resulting discrete set of equations. The implicit method is benchmarked against linear theory results for the relativistic Landau damping for which analytical expressions using the Maxwell-Jüttner distribution function are derived. We note that, independently from the shape of the distribution function, the relativistic treatment features collective behaviours that do not exist in the nonrelativistic case. The numericalmore » study of the relativistic two-stream instability completes the set of benchmarking tests.« less

  3. A Nonlinear Multigrid Solver for an Atmospheric General Circulation Model Based on Semi-Implicit Semi-Lagrangian Advection of Potential Vorticity

    NASA Technical Reports Server (NTRS)

    McCormick, S.; Ruge, John W.

    1998-01-01

    This work represents a part of a project to develop an atmospheric general circulation model based on the semi-Lagrangian advection of potential vorticity (PC) with divergence as the companion prognostic variable.

  4. 21 CFR 101.13 - general principles.

    Code of Federal Regulations, 2010 CFR

    1996-04-01

    ... content claims FOOD AND DRUGS FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES--CONTINUED FOOD FOR HUMAN CONSUMPTION FOOD LABELING General Provisions Sec. 101.13 Nutrient content claims... supplements). (b) A claim that expressly or implicitly characterizes the level of a nutrient (nutrient content...

  5. Studies of implicit and explicit solution techniques in transient thermal analysis of structures

    NASA Technical Reports Server (NTRS)

    Adelman, H. M.; Haftka, R. T.; Robinson, J. C.

    1982-01-01

    Studies aimed at an increase in the efficiency of calculating transient temperature fields in complex aerospace vehicle structures are reported. The advantages and disadvantages of explicit and implicit algorithms are discussed and a promising set of implicit algorithms with variable time steps, known as GEARIB, is described. Test problems, used for evaluating and comparing various algorithms, are discussed and finite element models of the configurations are described. These problems include a coarse model of the Space Shuttle wing, an insulated frame tst article, a metallic panel for a thermal protection system, and detailed models of sections of the Space Shuttle wing. Results generally indicate a preference for implicit over explicit algorithms for transient structural heat transfer problems when the governing equations are stiff (typical of many practical problems such as insulated metal structures). The effects on algorithm performance of different models of an insulated cylinder are demonstrated. The stiffness of the problem is highly sensitive to modeling details and careful modeling can reduce the stiffness of the equations to the extent that explicit methods may become the best choice. Preliminary applications of a mixed implicit-explicit algorithm and operator splitting techniques for speeding up the solution of the algebraic equations are also described.

  6. Of Meat and Men: Sex Differences in Implicit and Explicit Attitudes Toward Meat.

    PubMed

    Love, Hamish J; Sulikowski, Danielle

    2018-01-01

    Modern attitudes to meat in both men and women reflect a strong meat-masculinity association. Sex differences in the relationship between meat and masculinity have not been previously explored. In the current study we used two IATs (implicit association tasks), a visual search task, and a questionnaire to measure implicit and explicit attitudes toward meat in men and women. Men exhibited stronger implicit associations between meat and healthiness than did women, but both sexes associated meat more strongly with 'healthy' than 'unhealthy' concepts. As 'healthy' was operationalized in the current study using terms such as "virile" and "powerful," this suggests that a meat-strength/power association may mediate the meat-masculinity link readily observed across western cultures. The sex difference was not related to explicit attitudes to meat, nor was it attributable to a variety of other factors, such as a generally more positive disposition toward meat in men than women. Men also exhibited an attention bias toward meats, compared to non-meat foods, while females exhibited more caution when searching for non-meat foods, compared to meat. These biases were not related to implicit attitudes, but did tend to increase with increasing hunger levels. Potential ultimate explanations for these differences, including sex differences in bio-physiological needs and receptivity to social signals are discussed.

  7. PIXIE3D: A Parallel, Implicit, eXtended MHD 3D Code.

    NASA Astrophysics Data System (ADS)

    Chacon, L.; Knoll, D. A.

    2004-11-01

    We report on the development of PIXIE3D, a 3D parallel, fully implicit Newton-Krylov extended primitive-variable MHD code in general curvilinear geometry. PIXIE3D employs a second-order, finite-volume-based spatial discretization that satisfies remarkable properties such as being conservative, solenoidal in the magnetic field, non-dissipative, and stable in the absence of physical dissipation.(L. Chacón , phComput. Phys. Comm.) submitted (2004) PIXIE3D employs fully-implicit Newton-Krylov methods for the time advance. Currently, first and second-order implicit schemes are available, although higher-order temporal implicit schemes can be effortlessly implemented within the Newton-Krylov framework. A successful, scalable, MG physics-based preconditioning strategy, similar in concept to previous 2D MHD efforts,(L. Chacón et al., phJ. Comput. Phys). 178 (1), 15- 36 (2002); phJ. Comput. Phys., 188 (2), 573-592 (2003) has been developed. We are currently in the process of parallelizing the code using the PETSc library, and a Newton-Krylov-Schwarz approach for the parallel treatment of the preconditioner. In this poster, we will report on both the serial and parallel performance of PIXIE3D, focusing primarily on scalability and CPU speedup vs. an explicit approach.

  8. Implicit learning of non-linguistic and linguistic regularities in children with dyslexia.

    PubMed

    Nigro, Luciana; Jiménez-Fernández, Gracia; Simpson, Ian C; Defior, Sylvia

    2016-07-01

    One of the hallmarks of dyslexia is the failure to automatise written patterns despite repeated exposure to print. Although many explanations have been proposed to explain this problem, researchers have recently begun to explore the possibility that an underlying implicit learning deficit may play a role in dyslexia. This hypothesis has been investigated through non-linguistic tasks exploring implicit learning in a general domain. In this study, we examined the abilities of children with dyslexia to implicitly acquire positional regularities embedded in both non-linguistic and linguistic stimuli. In experiment 1, 42 children (21 with dyslexia and 21 typically developing) were exposed to rule-governed shape sequences; whereas in experiment 2, a new group of 42 children were exposed to rule-governed letter strings. Implicit learning was assessed in both experiments via a forced-choice task. Experiments 1 and 2 showed a similar pattern of results. ANOVA analyses revealed no significant differences between the dyslexic and the typically developing group, indicating that children with dyslexia are not impaired in the acquisition of simple positional regularities, regardless of the nature of the stimuli. However, within group t-tests suggested that children from the dyslexic group could not transfer the underlying positional rules to novel instances as efficiently as typically developing children.

  9. Action Being Character: A Promising Perspective on the Solution Concept of Game Theory

    PubMed Central

    Deng, Kuiying; Chu, Tianguang

    2011-01-01

    The inconsistency of predictions from solution concepts of conventional game theory with experimental observations is an enduring question. These solution concepts are based on the canonical rationality assumption that people are exclusively self-regarding utility maximizers. In this article, we think this assumption is problematic and, instead, assume that rational economic agents act as if they were maximizing their implicit utilities, which turns out to be a natural extension of the canonical rationality assumption. Implicit utility is defined by a player's character to reflect his personal weighting between cooperative, individualistic, and competitive social value orientations. The player who actually faces an implicit game chooses his strategy based on the common belief about the character distribution for a general player and the self-estimation of his own character, and he is not concerned about which strategies other players will choose and will never feel regret about his decision. It is shown by solving five paradigmatic games, the Dictator game, the Ultimatum game, the Prisoner's Dilemma game, the Public Goods game, and the Battle of the Sexes game, that the framework of implicit game and its corresponding solution concept, implicit equilibrium, based on this alternative assumption have potential for better explaining people's actual behaviors in social decision making situations. PMID:21573055

  10. Action being character: a promising perspective on the solution concept of game theory.

    PubMed

    Deng, Kuiying; Chu, Tianguang

    2011-05-09

    The inconsistency of predictions from solution concepts of conventional game theory with experimental observations is an enduring question. These solution concepts are based on the canonical rationality assumption that people are exclusively self-regarding utility maximizers. In this article, we think this assumption is problematic and, instead, assume that rational economic agents act as if they were maximizing their implicit utilities, which turns out to be a natural extension of the canonical rationality assumption. Implicit utility is defined by a player's character to reflect his personal weighting between cooperative, individualistic, and competitive social value orientations. The player who actually faces an implicit game chooses his strategy based on the common belief about the character distribution for a general player and the self-estimation of his own character, and he is not concerned about which strategies other players will choose and will never feel regret about his decision. It is shown by solving five paradigmatic games, the Dictator game, the Ultimatum game, the Prisoner's Dilemma game, the Public Goods game, and the Battle of the Sexes game, that the framework of implicit game and its corresponding solution concept, implicit equilibrium, based on this alternative assumption have potential for better explaining people's actual behaviors in social decision making situations.

  11. Retention of Implicit Sequence Learning in Persons who Stutter and Persons with Parkinson's Disease

    PubMed Central

    Smits-Bandstra, Sarah; Gracco, Vincent

    2014-01-01

    This study investigated the retention of implicit sequence learning in 14 persons with Parkinson's disease (PPD), 14 persons who stutter (PWS) and 14 control participants. Participants completed a nonsense syllable serial reaction time task in a 120-minute session. Participants named aloud four syllables in response to four visual stimuli. The syllables formed a repeating 8-item sequence not made known to participants. After one week, participants completed a 60-minute retention session that included an explicit learning questionnaire and a sequence generation task. PPD showed retention of general learning equivalent to controls but PWS's reaction times were significantly slower on early trials of the retention test relative to other groups. Controls showed implicit learning during the initial session that was retained on the retention test. In contrast, PPD and PWS did not demonstrate significant implicit learning until the retention test suggesting intact, but delayed, learning and retention of implicit sequencing skills. All groups demonstrated similar limited explicit sequence knowledge. Performance differences between PWS and PPD relative to controls during the initial session and on early retention trials indicated possible dysfunction of the cortico-striato-thalamo-cortical loop. The etiological implications for stuttering, and clinical implications for both populations, of this dysfunction are discussed. PMID:23844763

  12. Studies of implicit and explicit solution techniques in transient thermal analysis of structures

    NASA Astrophysics Data System (ADS)

    Adelman, H. M.; Haftka, R. T.; Robinson, J. C.

    1982-08-01

    Studies aimed at an increase in the efficiency of calculating transient temperature fields in complex aerospace vehicle structures are reported. The advantages and disadvantages of explicit and implicit algorithms are discussed and a promising set of implicit algorithms with variable time steps, known as GEARIB, is described. Test problems, used for evaluating and comparing various algorithms, are discussed and finite element models of the configurations are described. These problems include a coarse model of the Space Shuttle wing, an insulated frame tst article, a metallic panel for a thermal protection system, and detailed models of sections of the Space Shuttle wing. Results generally indicate a preference for implicit over explicit algorithms for transient structural heat transfer problems when the governing equations are stiff (typical of many practical problems such as insulated metal structures). The effects on algorithm performance of different models of an insulated cylinder are demonstrated. The stiffness of the problem is highly sensitive to modeling details and careful modeling can reduce the stiffness of the equations to the extent that explicit methods may become the best choice. Preliminary applications of a mixed implicit-explicit algorithm and operator splitting techniques for speeding up the solution of the algebraic equations are also described.

  13. Implicit theories concerning the intelligence of individuals with Down syndrome.

    PubMed

    Enea-Drapeau, Claire; Carlier, Michèle; Huguet, Pascal

    2017-01-01

    Studies over the past three decades have shown that learning difficulties are not only determined by neurological disorders, but also by motivational and/or socio-cognitive factors Among these factors, implicit theories of intelligence (also referred to as conceptions, mindsets or beliefs about intelligence) are key elements. The belief that intelligence is fixed (entity theory), as opposed to malleable (incremental theory), is generally associated with negative teaching practices and poorer student outcomes, yet beliefs about the intelligence of individuals with intellectual disabilities have not received much attention. We propose the first study on conceptions of intelligence of persons with intellectual disabilities, here people with Down syndrome. Participants were 55 professionally qualified people working with individuals with intellectual disabilities and 81 adults from the community. We compared what both groups of participants believe about intelligence of typical people and what they believe about the intelligence of individuals with Down syndrome. We also investigated implicit theories of intelligence as predictors of explicit judgments about intelligence and implicit attitudes toward people with Down syndrome. Whatever the work experience in the field of intellectual disability, implicit theories of intelligence were found to be less incremental when considering people with Down syndrome than when considering typical people; and the stronger the belief in entity theory, the more negative (and less positive) the judgments expressed explicitly. Implicit theories of intelligence were also found to be predictors of negative implicit attitude but only in adults from the community. These findings offer prospects for improving practices by people working in the field of intellectual disability. They might interest a wide range of people caring for people with intellectual disabilities, such as teachers, but also other professional caregivers, and other scientists focusing on intellectual disabilities or social cognition.

  14. Implicit theories concerning the intelligence of individuals with Down syndrome

    PubMed Central

    Carlier, Michèle; Huguet, Pascal

    2017-01-01

    Studies over the past three decades have shown that learning difficulties are not only determined by neurological disorders, but also by motivational and/or socio-cognitive factors Among these factors, implicit theories of intelligence (also referred to as conceptions, mindsets or beliefs about intelligence) are key elements. The belief that intelligence is fixed (entity theory), as opposed to malleable (incremental theory), is generally associated with negative teaching practices and poorer student outcomes, yet beliefs about the intelligence of individuals with intellectual disabilities have not received much attention. We propose the first study on conceptions of intelligence of persons with intellectual disabilities, here people with Down syndrome. Participants were 55 professionally qualified people working with individuals with intellectual disabilities and 81 adults from the community. We compared what both groups of participants believe about intelligence of typical people and what they believe about the intelligence of individuals with Down syndrome. We also investigated implicit theories of intelligence as predictors of explicit judgments about intelligence and implicit attitudes toward people with Down syndrome. Whatever the work experience in the field of intellectual disability, implicit theories of intelligence were found to be less incremental when considering people with Down syndrome than when considering typical people; and the stronger the belief in entity theory, the more negative (and less positive) the judgments expressed explicitly. Implicit theories of intelligence were also found to be predictors of negative implicit attitude but only in adults from the community. These findings offer prospects for improving practices by people working in the field of intellectual disability. They might interest a wide range of people caring for people with intellectual disabilities, such as teachers, but also other professional caregivers, and other scientists focusing on intellectual disabilities or social cognition. PMID:29166393

  15. The effect of social exclusion on state paranoia and explicit and implicit self-esteem in a non-clinical sample.

    PubMed

    Stewart, C; Rogers, F; Pilch, M; Stewart, I; Barnes-Holmes, Y; Westermann, S

    2017-12-01

    The relationship between self-esteem and paranoia may be influenced by social stress. This study aimed to replicate previous research on the impact ofsocial exclusion on paranoia and self-esteem in a non-clinical sample and to extend this work by examining the effect of exclusion on self-esteem at the 'implicit' level. Non-clinical participants (N = 85) were randomly allocated to the Inclusion or Exclusion condition of a virtual ball-toss game ('Cyberball'). They completed self-reportmeasures of state paranoia and self-esteem, and two implicit measures of self-esteem - theImplicit Association Task (IAT) and Implicit Relational Assessment Procedure (IRAP) -prior to and after exposure to Cyberball. Social exclusion increased state paranoia. This effect was moderated by distress associated with trait paranoia. Exclusion was also associated with decreased self-reported self-esteem, as well as reduced implicit self-esteem on the IAT. Changes in self-reported self-esteem were associated with state paranoia at post-Cyberball. The IRAP indicated that reductions in implicit self-esteem may be due to increases in 'Me-Negative' and 'Others-Positive' biases (rather than reductions in 'Me-Positive' bias). The current study involved a non-clinical sample and so findings cannot be generalized to clinical paranoia. These findings are consistent with previous evidence that paranoia is associated with negative self-evaluations, whereas positive self-evaluations can persist in paranoia. They also provide support for the suggestion that investigations of self-esteem in paranoia should extend beyond global self-esteem and might benefit from a distinction between positive and negative components. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The neural correlates of implicit self-relevant processing in low self-esteem: an ERP study.

    PubMed

    Yang, Juan; Guan, Lili; Dedovic, Katarina; Qi, Mingming; Zhang, Qinglin

    2012-08-30

    Previous neuroimaging studies have shown that implicit and explicit processing of self-relevant (schematic) material elicit activity in many of the same brain regions. Electrophysiological studies on the neural processing of explicit self-relevant cues have generally supported the view that P300 is an index of attention to self-relevant stimuli; however, there has been no study to date investigating the temporal course of implicit self-relevant processing. The current study seeks to investigate the time course involved in implicit self-processing by comparing processing of self-relevant with non-self-relevant words while subjects are making a judgment about color of the words in an implicit attention task. Sixteen low self-esteem participants were examined using event-related potentials technology (ERP). We hypothesized that this implicit attention task would involve P2 component rather than the P300 component. Indeed, P2 component has been associated with perceptual analysis and attentional allocation and may be more likely to occur in unconscious conditions such as this task. Results showed that latency of P2 component, which indexes the time required for perceptual analysis, was more prolonged in processing self-relevant words compared to processing non-self-relevant words. Our results suggested that the judgment of the color of the word interfered with automatic processing of self-relevant information and resulted in less efficient processing of self-relevant word. Together with previous ERP studies examining processing of explicit self-relevant cues, these findings suggest that the explicit and the implicit processing of self-relevant information would not elicit the same ERP components. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Effects of gestational age on brain volume and cognitive functions in generally healthy very preterm born children during school-age: A voxel-based morphometry study.

    PubMed

    Lemola, Sakari; Oser, Nadine; Urfer-Maurer, Natalie; Brand, Serge; Holsboer-Trachsler, Edith; Bechtel, Nina; Grob, Alexander; Weber, Peter; Datta, Alexandre N

    2017-01-01

    To determine whether the relationship of gestational age (GA) with brain volumes and cognitive functions is linear or whether it follows a threshold model in preterm and term born children during school-age. We studied 106 children (M = 10 years 1 month, SD = 16 months; 40 females) enrolled in primary school: 57 were healthy very preterm children (10 children born 24-27 completed weeks' gestation (extremely preterm), 14 children born 28-29 completed weeks' gestation, 19 children born 30-31 completed weeks' gestation (very preterm), and 14 born 32 completed weeks' gestation (moderately preterm)) all born appropriate for GA (AGA) and 49 term-born children. Neuroimaging involved voxel-based morphometry with the statistical parametric mapping software. Cognitive functions were assessed with the WISC-IV. General Linear Models and multiple regressions were conducted controlling age, sex, and maternal education. Compared to groups of children born 30 completed weeks' gestation and later, children born <28 completed weeks' gestation had less gray matter volume (GMV) and white matter volume (WMV) and poorer cognitive functions including decreased full scale IQ, and processing speed. Differences in GMV partially mediated the relationship between GA and full scale IQ in preterm born children. In preterm children who are born AGA and without major complications GA is associated with brain volume and cognitive functions. In particular, decreased brain volume becomes evident in the extremely preterm group (born <28 completed weeks' gestation). In preterm children born 30 completed weeks' gestation and later the relationship of GA with brain volume and cognitive functions may be less strong as previously thought.

  18. Supersymmetric Dirac Born Infeld action with self-dual mass term

    NASA Astrophysics Data System (ADS)

    Nishino, Hitoshi; Rajpoot, Subhash; Reed, Kevin

    2005-05-01

    We introduce a Dirac Born Infeld action to a self-dual N = 1 supersymmetric vector multiplet in three dimensions. This action is based on the supersymmetric generalized self-duality in odd dimensions developed originally by Townsend, Pilch and van Nieuwenhuizen. Even though such a self-duality had been supposed to be very difficult to generalize to a supersymmetrically interacting system, we show that the Dirac Born Infeld action is actually compatible with supersymmetry and self-duality in three dimensions, even though the original self-duality receives corrections by the Dirac Born Infeld action. The interactions can be further generalized to arbitrary (non)polynomial interactions. As a by-product, we also show that a third-rank field strength leads to a more natural formulation of self-duality in 3D. We also show an interesting role played by the third-rank field strength leading to supersymmetry breaking, in addition to accommodating a Chern Simons form.

  19. Implicit bias among physicians and its prediction of thrombolysis decisions for black and white patients.

    PubMed

    Green, Alexander R; Carney, Dana R; Pallin, Daniel J; Ngo, Long H; Raymond, Kristal L; Iezzoni, Lisa I; Banaji, Mahzarin R

    2007-09-01

    Studies documenting racial/ethnic disparities in health care frequently implicate physicians' unconscious biases. No study to date has measured physicians' unconscious racial bias to test whether this predicts physicians' clinical decisions. To test whether physicians show implicit race bias and whether the magnitude of such bias predicts thrombolysis recommendations for black and white patients with acute coronary syndromes. An internet-based tool comprising a clinical vignette of a patient presenting to the emergency department with an acute coronary syndrome, followed by a questionnaire and three Implicit Association Tests (IATs). Study invitations were e-mailed to all internal medicine and emergency medicine residents at four academic medical centers in Atlanta and Boston; 287 completed the study, met inclusion criteria, and were randomized to either a black or white vignette patient. IAT scores (normal continuous variable) measuring physicians' implicit race preference and perceptions of cooperativeness. Physicians' attribution of symptoms to coronary artery disease for vignette patients with randomly assigned race, and their decisions about thrombolysis. Assessment of physicians' explicit racial biases by questionnaire. Physicians reported no explicit preference for white versus black patients or differences in perceived cooperativeness. In contrast, IATs revealed implicit preference favoring white Americans (mean IAT score = 0.36, P < .001, one-sample t test) and implicit stereotypes of black Americans as less cooperative with medical procedures (mean IAT score 0.22, P < .001), and less cooperative generally (mean IAT score 0.30, P < .001). As physicians' prowhite implicit bias increased, so did their likelihood of treating white patients and not treating black patients with thrombolysis (P = .009). This study represents the first evidence of unconscious (implicit) race bias among physicians, its dissociation from conscious (explicit) bias, and its predictive validity. Results suggest that physicians' unconscious biases may contribute to racial/ethnic disparities in use of medical procedures such as thrombolysis for myocardial infarction.

  20. Tunable, mixed-resolution modeling using library-based Monte Carlo and graphics processing units

    PubMed Central

    Mamonov, Artem B.; Lettieri, Steven; Ding, Ying; Sarver, Jessica L.; Palli, Rohith; Cunningham, Timothy F.; Saxena, Sunil; Zuckerman, Daniel M.

    2012-01-01

    Building on our recently introduced library-based Monte Carlo (LBMC) approach, we describe a flexible protocol for mixed coarse-grained (CG)/all-atom (AA) simulation of proteins and ligands. In the present implementation of LBMC, protein side chain configurations are pre-calculated and stored in libraries, while bonded interactions along the backbone are treated explicitly. Because the AA side chain coordinates are maintained at minimal run-time cost, arbitrary sites and interaction terms can be turned on to create mixed-resolution models. For example, an AA region of interest such as a binding site can be coupled to a CG model for the rest of the protein. We have additionally developed a hybrid implementation of the generalized Born/surface area (GBSA) implicit solvent model suitable for mixed-resolution models, which in turn was ported to a graphics processing unit (GPU) for faster calculation. The new software was applied to study two systems: (i) the behavior of spin labels on the B1 domain of protein G (GB1) and (ii) docking of randomly initialized estradiol configurations to the ligand binding domain of the estrogen receptor (ERα). The performance of the GPU version of the code was also benchmarked in a number of additional systems. PMID:23162384

  1. Consistent free energy landscapes and thermodynamic properties of small proteins based on a single all-atom force field employing an implicit solvation.

    PubMed

    Kim, Eunae; Jang, Soonmin; Pak, Youngshang

    2007-10-14

    We have attempted to improve the PARAM99 force field in conjunction with the generalized Born (GB) solvation model with a surface area correction for more consistent protein folding simulations. For this purpose, using an extended alphabeta training set of five well-studied molecules with various folds (alpha, beta, and betabetaalpha), a previously modified version of PARAM99/GBSA is further refined, such that all native states of the five training species correspond to their lowest free energy minimum states. The resulting modified force field (PARAM99MOD5/GBSA) clearly produces reasonably acceptable conformational free energy surfaces of the training set with correct identifications of their native states in the free energy minimum states. Moreover, due to its well-balanced nature, this new force field is expected to describe secondary structure propensities of diverse folds in a more consistent manner. Remarkably, temperature dependent behaviors simulated with the current force field are in good agreement with the experiment. This agreement is a significant improvement over the existing standard all-atom force fields. In addition, fundamentally important thermodynamic quantities, such as folding enthalpy (DeltaH) and entropy (DeltaS), agree reasonably well with the experimental data.

  2. Next generation extended Lagrangian first principles molecular dynamics

    NASA Astrophysics Data System (ADS)

    Niklasson, Anders M. N.

    2017-08-01

    Extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] is formulated for general Hohenberg-Kohn density-functional theory and compared with the extended Lagrangian framework of first principles molecular dynamics by Car and Parrinello [Phys. Rev. Lett. 55, 2471 (1985)]. It is shown how extended Lagrangian Born-Oppenheimer molecular dynamics overcomes several shortcomings of regular, direct Born-Oppenheimer molecular dynamics, while improving or maintaining important features of Car-Parrinello simulations. The accuracy of the electronic degrees of freedom in extended Lagrangian Born-Oppenheimer molecular dynamics, with respect to the exact Born-Oppenheimer solution, is of second-order in the size of the integration time step and of fourth order in the potential energy surface. Improved stability over recent formulations of extended Lagrangian Born-Oppenheimer molecular dynamics is achieved by generalizing the theory to finite temperature ensembles, using fractional occupation numbers in the calculation of the inner-product kernel of the extended harmonic oscillator that appears as a preconditioner in the electronic equations of motion. Material systems that normally exhibit slow self-consistent field convergence can be simulated using integration time steps of the same order as in direct Born-Oppenheimer molecular dynamics, but without the requirement of an iterative, non-linear electronic ground-state optimization prior to the force evaluations and without a systematic drift in the total energy. In combination with proposed low-rank and on the fly updates of the kernel, this formulation provides an efficient and general framework for quantum-based Born-Oppenheimer molecular dynamics simulations.

  3. Next generation extended Lagrangian first principles molecular dynamics.

    PubMed

    Niklasson, Anders M N

    2017-08-07

    Extended Lagrangian Born-Oppenheimer molecular dynamics [A. M. N. Niklasson, Phys. Rev. Lett. 100, 123004 (2008)] is formulated for general Hohenberg-Kohn density-functional theory and compared with the extended Lagrangian framework of first principles molecular dynamics by Car and Parrinello [Phys. Rev. Lett. 55, 2471 (1985)]. It is shown how extended Lagrangian Born-Oppenheimer molecular dynamics overcomes several shortcomings of regular, direct Born-Oppenheimer molecular dynamics, while improving or maintaining important features of Car-Parrinello simulations. The accuracy of the electronic degrees of freedom in extended Lagrangian Born-Oppenheimer molecular dynamics, with respect to the exact Born-Oppenheimer solution, is of second-order in the size of the integration time step and of fourth order in the potential energy surface. Improved stability over recent formulations of extended Lagrangian Born-Oppenheimer molecular dynamics is achieved by generalizing the theory to finite temperature ensembles, using fractional occupation numbers in the calculation of the inner-product kernel of the extended harmonic oscillator that appears as a preconditioner in the electronic equations of motion. Material systems that normally exhibit slow self-consistent field convergence can be simulated using integration time steps of the same order as in direct Born-Oppenheimer molecular dynamics, but without the requirement of an iterative, non-linear electronic ground-state optimization prior to the force evaluations and without a systematic drift in the total energy. In combination with proposed low-rank and on the fly updates of the kernel, this formulation provides an efficient and general framework for quantum-based Born-Oppenheimer molecular dynamics simulations.

  4. How robust is the IAT? Measuring and manipulating implicit attitudes of East- and West-Germans.

    PubMed

    Kühnen, U; Schiessl, M; Bauer, N; Paulig, N; Pöhlmann, C; Schmidthals, K

    2001-01-01

    We investigated consequences of priming East-West-German related self-knowledge for the strength of implicit, ingroup-directed positive evaluations among East- and West-Germans. Based on previous studies we predicted opposite effects of self-knowledge priming for East- and West-Germans. Since in general the East-German stereotype is regarded as more negative than the West-German one, bringing to mind East-West-related self-knowledge (relative to neutral priming) was expected to attenuate ingroup favoritism for East-Germans, but to increase it for West-Germans. After having fulfilled the priming tasks, participants worked on an IAT-version in which the to be classified stimuli were East- or West-German city names (dimension 1) and positive or negative adjectives (dimension 2). Results of Experiment 1 showed (a) that East- and West-German students implicitly evaluated their ingroups as more positive than the outgroups and (b) confirmed the predictions of the priming influence. Experiment 2 replicated these findings with more representative samples from East- and West-Germany. The results are discussed with regard to underlying processes of implicit attitudes in intergroup contexts.

  5. Fully implicit Particle-in-cell algorithms for multiscale plasma simulation

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

    Chacon, Luis

    The outline of the paper is as follows: Particle-in-cell (PIC) methods for fully ionized collisionless plasmas, explicit vs. implicit PIC, 1D ES implicit PIC (charge and energy conservation, moment-based acceleration), and generalization to Multi-D EM PIC: Vlasov-Darwin model (review and motivation for Darwin model, conservation properties (energy, charge, and canonical momenta), and numerical benchmarks). The author demonstrates a fully implicit, fully nonlinear, multidimensional PIC formulation that features exact local charge conservation (via a novel particle mover strategy), exact global energy conservation (no particle self-heating or self-cooling), adaptive particle orbit integrator to control errors in momentum conservation, and canonical momenta (EM-PICmore » only, reduced dimensionality). The approach is free of numerical instabilities: ω peΔt >> 1, and Δx >> λ D. It requires many fewer dofs (vs. explicit PIC) for comparable accuracy in challenging problems. Significant CPU gains (vs explicit PIC) have been demonstrated. The method has much potential for efficiency gains vs. explicit in long-time-scale applications. Moment-based acceleration is effective in minimizing N FE, leading to an optimal algorithm.« less

  6. On the performance of explicit and implicit algorithms for transient thermal analysis

    NASA Astrophysics Data System (ADS)

    Adelman, H. M.; Haftka, R. T.

    1980-09-01

    The status of an effort to increase the efficiency of calculating transient temperature fields in complex aerospace vehicle structures is described. The advantages and disadvantages of explicit and implicit algorithms are discussed. A promising set of implicit algorithms, known as the GEAR package is described. Four test problems, used for evaluating and comparing various algorithms, have been selected and finite element models of the configurations are discribed. These problems include a space shuttle frame component, an insulated cylinder, a metallic panel for a thermal protection system and a model of the space shuttle orbiter wing. Calculations were carried out using the SPAR finite element program, the MITAS lumped parameter program and a special purpose finite element program incorporating the GEAR algorithms. Results generally indicate a preference for implicit over explicit algorithms for solution of transient structural heat transfer problems when the governing equations are stiff. Careful attention to modeling detail such as avoiding thin or short high-conducting elements can sometimes reduce the stiffness to the extent that explicit methods become advantageous.

  7. 42 CFR 413.5 - Cost reimbursement: General.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... costs, are recognized. Furthermore, the share of the total institutional cost that is borne by the... borne by other patients. Conversely, costs attributable to other patients of the institution are not to be borne by the program. Thus, the application of this approach, with appropriate accounting support...

  8. 42 CFR 413.5 - Cost reimbursement: General.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... costs, are recognized. Furthermore, the share of the total institutional cost that is borne by the... borne by other patients. Conversely, costs attributable to other patients of the institution are not to be borne by the program. Thus, the application of this approach, with appropriate accounting support...

  9. 42 CFR 413.5 - Cost reimbursement: General.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... costs, are recognized. Furthermore, the share of the total institutional cost that is borne by the... borne by other patients. Conversely, costs attributable to other patients of the institution are not to be borne by the program. Thus, the application of this approach, with appropriate accounting support...

  10. An implicit-iterative solution of the heat conduction equation with a radiation boundary condition

    NASA Technical Reports Server (NTRS)

    Williams, S. D.; Curry, D. M.

    1977-01-01

    For the problem of predicting one-dimensional heat transfer between conducting and radiating mediums by an implicit finite difference method, four different formulations were used to approximate the surface radiation boundary condition while retaining an implicit formulation for the interior temperature nodes. These formulations are an explicit boundary condition, a linearized boundary condition, an iterative boundary condition, and a semi-iterative boundary method. The results of these methods in predicting surface temperature on the space shuttle orbiter thermal protection system model under a variety of heating rates were compared. The iterative technique caused the surface temperature to be bounded at each step. While the linearized and explicit methods were generally more efficient, the iterative and semi-iterative techniques provided a realistic surface temperature response without requiring step size control techniques.

  11. Multithreaded implicitly dealiased convolutions

    NASA Astrophysics Data System (ADS)

    Roberts, Malcolm; Bowman, John C.

    2018-03-01

    Implicit dealiasing is a method for computing in-place linear convolutions via fast Fourier transforms that decouples work memory from input data. It offers easier memory management and, for long one-dimensional input sequences, greater efficiency than conventional zero-padding. Furthermore, for convolutions of multidimensional data, the segregation of data and work buffers can be exploited to reduce memory usage and execution time significantly. This is accomplished by processing and discarding data as it is generated, allowing work memory to be reused, for greater data locality and performance. A multithreaded implementation of implicit dealiasing that accepts an arbitrary number of input and output vectors and a general multiplication operator is presented, along with an improved one-dimensional Hermitian convolution that avoids the loop dependency inherent in previous work. An alternate data format that can accommodate a Nyquist mode and enhance cache efficiency is also proposed.

  12. Adolescents' explicit and implicit evaluations of hypothetical and actual peers with different bullying participant roles.

    PubMed

    Pouwels, J Loes; Lansu, Tessa A M; Cillessen, Antonius H N

    2017-07-01

    This study examined how adolescents evaluate bullying at three levels of specificity: (a) the general concept of bullying, (b) hypothetical peers in different bullying participant roles, and (c) actual peers in different bullying participant roles. Participants were 163 predominantly ethnic majority adolescents in The Netherlands (58% girls; M age =16.34years, SD=0.79). For the hypothetical peers, we examined adolescents' explicit evaluations as well as their implicit evaluations. Adolescents evaluated the general concept of bullying negatively. Adolescents' explicit evaluations of hypothetical and actual peers in the bullying roles depended on their own role, but adolescents' implicit evaluations of hypothetical peers did not. Adolescents' explicit evaluations of hypothetical peers and actual peers were different. Hypothetical bullies were evaluated negatively by all classmates, whereas hypothetical victims were evaluated relatively positively compared with the other roles. However, when adolescents evaluated their actual classmates, the differences between bullies and the other roles were smaller, whereas victims were evaluated the most negatively of all roles. Further research should take into account that adolescents' evaluations of hypothetical peers differ from their evaluations of actual peers. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Racial bias in implicit danger associations generalizes to older male targets.

    PubMed

    Lundberg, Gustav J W; Neel, Rebecca; Lassetter, Bethany; Todd, Andrew R

    2018-01-01

    Across two experiments, we examined whether implicit stereotypes linking younger (~28-year-old) Black versus White men with violence and criminality extend to older (~68-year-old) Black versus White men. In Experiment 1, participants completed a sequential priming task wherein they categorized objects as guns or tools after seeing briefly-presented facial images of men who varied in age (younger versus older) and race (Black versus White). In Experiment 2, we used different face primes of younger and older Black and White men, and participants categorized words as 'threatening' or 'safe.' Results consistently revealed robust racial biases in object and word identification: Dangerous objects and words were identified more easily (faster response times, lower error rates), and non-dangerous objects and words were identified less easily, after seeing Black face primes than after seeing White face primes. Process dissociation procedure analyses, which aim to isolate the unique contributions of automatic and controlled processes to task performance, further indicated that these effects were driven entirely by racial biases in automatic processing. In neither experiment did prime age moderate racial bias, suggesting that the implicit danger associations commonly evoked by younger Black versus White men appear to generalize to older Black versus White men.

  14. A fast efficient implicit scheme for the gasdynamic equations using a matrix reduction technique

    NASA Technical Reports Server (NTRS)

    Barth, T. J.; Steger, J. L.

    1985-01-01

    An efficient implicit finite-difference algorithm for the gasdynamic equations utilizing matrix reduction techniques is presented. A significant reduction in arithmetic operations is achieved without loss of the stability characteristics generality found in the Beam and Warming approximate factorization algorithm. Steady-state solutions to the conservative Euler equations in generalized coordinates are obtained for transonic flows and used to show that the method offers computational advantages over the conventional Beam and Warming scheme. Existing Beam and Warming codes can be retrofit with minimal effort. The theoretical extension of the matrix reduction technique to the full Navier-Stokes equations in Cartesian coordinates is presented in detail. Linear stability, using a Fourier stability analysis, is demonstrated and discussed for the one-dimensional Euler equations.

  15. Correlation between white matter microstructure and executive functions suggests early developmental influence on long fibre tracts in preterm born adolescents.

    PubMed

    Vollmer, Brigitte; Lundequist, Aiko; Mårtensson, Gustaf; Nagy, Zoltan; Lagercrantz, Hugo; Smedler, Ann-Charlotte; Forssberg, Hans

    2017-01-01

    Executive functions are frequently a weakness in children born preterm. We examined associations of executive functions and general cognitive abilities with brain structure in preterm born adolescents who were born with appropriate weight for gestational age and who have no radiological signs of preterm brain injury on neuroimaging. The Stockholm Neonatal Project (SNP) is a longitudinal, population-based study of children born preterm (<36 weeks of gestation) with very low birth weight (<1501g) between 1988-1993. At age 18 years (mean 18 years, SD 2 weeks) 134 preterm born and 94 full term participants underwent psychological assessment (general intelligence, executive function measures). Of these, 71 preterm and 63 full term participants underwent Magnetic Resonance Imaging (MRI) at mean 15.2 years (range 12-18 years), including 3D T1-weighted images for volumetric analyses and Diffusion Tensor Imaging (DTI) for assessment of white matter microstructure. Group comparisons of regional grey and white matter volumes and fractional anisotropy (FA, as a measure of white matter microstructure) and, within each group, correlation analyses of cognitive measures with MRI metrics were carried out. Significant differences in grey and white matter regional volumes and widespread differences in FA were seen between the two groups. No significant correlations were found between cognitive measures and brain volumes in any group after correction for multiple comparisons. However, there were significant correlations between FA in projection fibres and long association fibres, linking frontal, temporal, parietal, and occipital lobes, and measures of executive function and general cognitive abilities in the preterm born adolescents, but not in the term born adolescents. In persons born preterm, in the absence of perinatal brain injury on visual inspection of MRI, widespread alterations in regional brain tissue volumes and microstructure are present in adolescence/young adulthood. Importantly, these alterations in WM tracts are correlated with measures of executive function and general cognitive abilities. Our findings suggest that disturbance of neural pathways, rather than changes in regional brain volumes, are involved in the impaired cognitive functions.

  16. Isolating Visual and Proprioceptive Components of Motor Sequence Learning in ASD.

    PubMed

    Sharer, Elizabeth A; Mostofsky, Stewart H; Pascual-Leone, Alvaro; Oberman, Lindsay M

    2016-05-01

    In addition to defining impairments in social communication skills, individuals with autism spectrum disorder (ASD) also show impairments in more basic sensory and motor skills. Development of new skills involves integrating information from multiple sensory modalities. This input is then used to form internal models of action that can be accessed when both performing skilled movements, as well as understanding those actions performed by others. Learning skilled gestures is particularly reliant on integration of visual and proprioceptive input. We used a modified serial reaction time task (SRTT) to decompose proprioceptive and visual components and examine whether patterns of implicit motor skill learning differ in ASD participants as compared with healthy controls. While both groups learned the implicit motor sequence during training, healthy controls showed robust generalization whereas ASD participants demonstrated little generalization when visual input was constant. In contrast, no group differences in generalization were observed when proprioceptive input was constant, with both groups showing limited degrees of generalization. The findings suggest, when learning a motor sequence, individuals with ASD tend to rely less on visual feedback than do healthy controls. Visuomotor representations are considered to underlie imitative learning and action understanding and are thereby crucial to social skill and cognitive development. Thus, anomalous patterns of implicit motor learning, with a tendency to discount visual feedback, may be an important contributor in core social communication deficits that characterize ASD. Autism Res 2016, 9: 563-569. © 2015 International Society for Autism Research, Wiley Periodicals, Inc. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

  17. Bluues: a program for the analysis of the electrostatic properties of proteins based on generalized Born radii

    PubMed Central

    2012-01-01

    Background The Poisson-Boltzmann (PB) equation and its linear approximation have been widely used to describe biomolecular electrostatics. Generalized Born (GB) models offer a convenient computational approximation for the more fundamental approach based on the Poisson-Boltzmann equation, and allows estimation of pairwise contributions to electrostatic effects in the molecular context. Results We have implemented in a single program most common analyses of the electrostatic properties of proteins. The program first computes generalized Born radii, via a surface integral and then it uses generalized Born radii (using a finite radius test particle) to perform electrostic analyses. In particular the ouput of the program entails, depending on user's requirement: 1) the generalized Born radius of each atom; 2) the electrostatic solvation free energy; 3) the electrostatic forces on each atom (currently in a dvelopmental stage); 4) the pH-dependent properties (total charge and pH-dependent free energy of folding in the pH range -2 to 18; 5) the pKa of all ionizable groups; 6) the electrostatic potential at the surface of the molecule; 7) the electrostatic potential in a volume surrounding the molecule; Conclusions Although at the expense of limited flexibility the program provides most common analyses with requirement of a single input file in PQR format. The results obtained are comparable to those obtained using state-of-the-art Poisson-Boltzmann solvers. A Linux executable with example input and output files is provided as supplementary material. PMID:22536964

  18. No childhood advantage in the acquisition of skill in using an artificial language rule.

    PubMed

    Ferman, Sara; Karni, Avi

    2010-10-27

    A leading notion is that language skill acquisition declines between childhood and adulthood. While several lines of evidence indicate that declarative ("what", explicit) memory undergoes maturation, it is commonly assumed that procedural ("how-to", implicit) memory, in children, is well established. The language superiority of children has been ascribed to the childhood reliance on implicit learning. Here we show that when 8-year-olds, 12-year-olds and young adults were provided with an equivalent multi-session training experience in producing and judging an artificial morphological rule (AMR), adults were superior to children of both age groups and the 8-year-olds were the poorest learners in all task parameters including in those that were clearly implicit. The AMR consisted of phonological transformations of verbs expressing a semantic distinction: whether the preceding noun was animate or inanimate. No explicit instruction of the AMR was provided. The 8-year-olds, unlike most adults and 12-year-olds, failed to explicitly uncover the semantic aspect of the AMR and subsequently to generalize it accurately to novel items. However, all participants learned to apply the AMR to repeated items and to generalize its phonological patterns to novel items, attaining accurate and fluent production, and exhibiting key characteristics of procedural memory. Nevertheless, adults showed a clear advantage in learning implicit task aspects, and in their long-term retention. Thus, our findings support the notion of age-dependent maturation in the establishment of declarative but also of procedural memory in a complex language task. In line with recent reports of no childhood advantage in non-linguistic skill learning, we propose that under some learning conditions adults can effectively express their language skill acquisition potential. Altogether, the maturational effects in the acquisition of an implicit AMR do not support a simple notion of a language skill learning advantage in children.

  19. Surfing the implicit wave.

    PubMed

    Shea, C H; Wulf, G; Whitacre, C A; Park, J H

    2001-08-01

    Implicit learning was investigated in two experiments involving a complex motor task. Participants were required to balance on a stabilometer and to move the platform on which they were standing to match a constantly changing target position. Experiment 1 examined whether a segment (middle third) that was repeated on each trial would be learned without participants becoming aware of the repetitions (i.e., implicitly). The purpose of Experiment 2 was to determine the relative effectiveness of explicit versus implicit learning. Here, two identical segments were presented on each trial (first and last thirds), with participants only being informed that one segment (either first or last) was repeated. The acquisition results from both experiments indicated large improvements in performance across 4 days of practice, with performance on the repeated segments being generally superior to that on the non-repeated segment. On the retention tests on Day 5, errors on the repeated segment(s) were smaller than those on the random segment(s). Furthermore, in Experiment 2, the errors on the repeated-known segment, although smaller than those on the random segment, were larger than those on the repeated-unknown segment. Interview results indicated that participants were not consciously aware that a segment was repeated unless they were informed. These results suggest that implicit learning can occur for relatively complex motor tasks and that withholding information concerning the regularities is more beneficial than providing this information.

  20. Implicit and explicit selective attention to smoking cues in smokers indexed by brain potentials.

    PubMed

    Littel, Marianne; Franken, Ingmar H A

    2011-04-01

    Substance use disorders are characterized by cognitive processing biases, such as automatically detecting and orienting attention towards drug-related stimuli. However, it is unclear how, when and what kind of attention (i.e. implicit, explicit) interacts with the processing of these stimuli. In addition, it is unclear whether smokers are hypersensitive to emotionally significant cues in general or to smoking-related cues in particular. The present event-related potential study aimed to enhance insight in drug-related processing biases by manipulating attention for smoking and other motivationally relevant (emotional) cues in smokers and non-smokers using a visual oddball task. Each of the stimulus categories served as a target (explicit attention; counting) or as a non-target (implicit attention; oddball) category. Compared with non-smokers, smokers' P300 (350-600 ms) was enhanced to smoking pictures under both attentional conditions. P300 amplitude did not differ between groups in response to positive, negative, and neutral cues. It can be concluded from this study that attention manipulation affects the P300 differently in smokers and non-smokers. Smokers display a specific bias to smoking-related cues, and this bias is present during both explicit and implicit attentional processing. Overall, it can be concluded that both explicit and implicit attentional processes appear to play an important role in drug-related processing bias.

  1. The base rate principle and the fairness principle in social judgment

    PubMed Central

    Cao, Jack; Banaji, Mahzarin R.

    2016-01-01

    Meet Jonathan and Elizabeth. One person is a doctor and the other is a nurse. Who is the doctor? When nothing else is known, the base rate principle favors Jonathan to be the doctor and the fairness principle favors both individuals equally. However, when individuating facts reveal who is actually the doctor, base rates and fairness become irrelevant, as the facts make the correct answer clear. In three experiments, explicit and implicit beliefs were measured before and after individuating facts were learned. These facts were either stereotypic (e.g., Jonathan is the doctor, Elizabeth is the nurse) or counterstereotypic (e.g., Elizabeth is the doctor, Jonathan is the nurse). Results showed that before individuating facts were learned, explicit beliefs followed the fairness principle, whereas implicit beliefs followed the base rate principle. After individuating facts were learned, explicit beliefs correctly aligned with stereotypic and counterstereotypic facts. Implicit beliefs, however, were immune to counterstereotypic facts and continued to follow the base rate principle. Having established the robustness and generality of these results, a fourth experiment verified that gender stereotypes played a causal role: when both individuals were male, explicit and implicit beliefs alike correctly converged with individuating facts. Taken together, these experiments demonstrate that explicit beliefs uphold fairness and incorporate obvious and relevant facts, but implicit beliefs uphold base rates and appear relatively impervious to counterstereotypic facts. PMID:27325760

  2. Of Meat and Men: Sex Differences in Implicit and Explicit Attitudes Toward Meat

    PubMed Central

    Love, Hamish J.; Sulikowski, Danielle

    2018-01-01

    Modern attitudes to meat in both men and women reflect a strong meat-masculinity association. Sex differences in the relationship between meat and masculinity have not been previously explored. In the current study we used two IATs (implicit association tasks), a visual search task, and a questionnaire to measure implicit and explicit attitudes toward meat in men and women. Men exhibited stronger implicit associations between meat and healthiness than did women, but both sexes associated meat more strongly with ‘healthy’ than ‘unhealthy’ concepts. As ‘healthy’ was operationalized in the current study using terms such as “virile” and “powerful,” this suggests that a meat-strength/power association may mediate the meat-masculinity link readily observed across western cultures. The sex difference was not related to explicit attitudes to meat, nor was it attributable to a variety of other factors, such as a generally more positive disposition toward meat in men than women. Men also exhibited an attention bias toward meats, compared to non-meat foods, while females exhibited more caution when searching for non-meat foods, compared to meat. These biases were not related to implicit attitudes, but did tend to increase with increasing hunger levels. Potential ultimate explanations for these differences, including sex differences in bio-physiological needs and receptivity to social signals are discussed. PMID:29731733

  3. The base rate principle and the fairness principle in social judgment.

    PubMed

    Cao, Jack; Banaji, Mahzarin R

    2016-07-05

    Meet Jonathan and Elizabeth. One person is a doctor and the other is a nurse. Who is the doctor? When nothing else is known, the base rate principle favors Jonathan to be the doctor and the fairness principle favors both individuals equally. However, when individuating facts reveal who is actually the doctor, base rates and fairness become irrelevant, as the facts make the correct answer clear. In three experiments, explicit and implicit beliefs were measured before and after individuating facts were learned. These facts were either stereotypic (e.g., Jonathan is the doctor, Elizabeth is the nurse) or counterstereotypic (e.g., Elizabeth is the doctor, Jonathan is the nurse). Results showed that before individuating facts were learned, explicit beliefs followed the fairness principle, whereas implicit beliefs followed the base rate principle. After individuating facts were learned, explicit beliefs correctly aligned with stereotypic and counterstereotypic facts. Implicit beliefs, however, were immune to counterstereotypic facts and continued to follow the base rate principle. Having established the robustness and generality of these results, a fourth experiment verified that gender stereotypes played a causal role: when both individuals were male, explicit and implicit beliefs alike correctly converged with individuating facts. Taken together, these experiments demonstrate that explicit beliefs uphold fairness and incorporate obvious and relevant facts, but implicit beliefs uphold base rates and appear relatively impervious to counterstereotypic facts.

  4. A differential equation for the Generalized Born radii.

    PubMed

    Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro

    2013-06-28

    The Generalized Born (GB) model offers a convenient way of representing electrostatics in complex macromolecules like proteins or nucleic acids. The computation of atomic GB radii is currently performed by different non-local approaches involving volume or surface integrals. Here we obtain a non-linear second-order partial differential equation for the Generalized Born radius, which may be solved using local iterative algorithms. The equation is derived under the assumption that the usual GB approximation to the reaction field obeys Laplace's equation. The equation admits as particular solutions the correct GB radii for the sphere and the plane. The tests performed on a set of 55 different proteins show an overall agreement with other reference GB models and "perfect" Poisson-Boltzmann based values.

  5. A Guide to Airborne, Impact, and Structure Borne Noise--Control in Multifamily Dwellings.

    ERIC Educational Resources Information Center

    Berendt, Raymond D.; And Others

    The control of noise on buildings is discussed extensively in this document, incorporating a broad range of criteria appropriate for isolating air borne, impact, and structure-borne noise associated with residential construction. Subject areas include--(1) noise types, sources, and transmission, (2) general principles of noise control, (3)…

  6. On gravitational waves in Born-Infeld inspired non-singular cosmologies

    NASA Astrophysics Data System (ADS)

    Beltrán Jiménez, Jose; Heisenberg, Lavinia; Olmo, Gonzalo J.; Rubiera-Garcia, Diego

    2017-10-01

    We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of the gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.

  7. On gravitational waves in Born-Infeld inspired non-singular cosmologies

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

    Jiménez, Jose Beltrán; Heisenberg, Lavinia; Olmo, Gonzalo J.

    We study the evolution of gravitational waves for non-singular cosmological solutions within the framework of Born-Infeld inspired gravity theories, with special emphasis on the Eddington-inspired Born-Infeld theory. We review the existence of two types of non-singular cosmologies, namely bouncing and asymptotically Minkowski solutions, from a perspective that makes their features more apparent. We study in detail the propagation of gravitational waves near these non-singular solutions and carefully discuss the origin and severity of the instabilities and strong coupling problems that appear. We also investigate the role of the adiabatic sound speed of the matter sector in the regularisation of themore » gravitational waves evolution. We extend our analysis to more general Born-Infeld inspired theories where analogous solutions are found. As a general conclusion, we obtain that the bouncing solutions are generally more prone to instabilities, while the asymptotically Minkowski solutions can be rendered stable, making them appealing models for the early universe.« less

  8. Motor learning and consolidation: the case of visuomotor rotation.

    PubMed

    Krakauer, John W

    2009-01-01

    Adaptation to visuomotor rotation is a particular form of motor learning distinct from force-field adaptation, sequence learning, and skill learning. Nevertheless, study of adaptation to visuomotor rotation has yielded a number of findings and principles that are likely of general importance to procedural learning and memory. First, rotation learning is implicit and appears to proceed through reduction in a visual prediction error generated by a forward model, such implicit adaptation occurs even when it is in conflict with an explicit task goal. Second, rotation learning is subject to different forms of interference: retrograde, anterograde through aftereffects, and contextual blocking of retrieval. Third, opposite rotations can be recalled within a short time interval without interference if implicit contextual cues (effector change) rather than explicit cues (color change) are used. Fourth, rotation learning consolidates both over time and with increased initial training (saturation learning).

  9. Threat and defense as goal regulation: from implicit goal conflict to anxious uncertainty, reactive approach motivation, and ideological extremism.

    PubMed

    Nash, Kyle; McGregor, Ian; Prentice, Mike

    2011-12-01

    Four studies investigated a goal regulation view of anxious uncertainty threat (Gray & McNaughton, 2000) and ideological defense. Participants (N = 444) were randomly assigned to have achievement or relationship goals implicitly primed. The implicit goal primes were followed by randomly assigned achievement or relationship threats that have reliably caused generalized, reactive approach motivation and ideological defense in past research. The threats caused anxious uncertainty (Study 1), reactive approach motivation (Studies 2 and 3), and reactive ideological conviction (Study 4) only when threat-relevant goals had first been primed, but not when threat-irrelevant goals had first been primed. Reactive ideological conviction (Study 4) was eliminated if participants were given an opportunity to attribute their anxiety to a mundane source. Results support a goal regulation view of anxious uncertainty, threat, and defense with potential for integrating theories of defensive compensation.

  10. Cultural differences in visual attention: Implications for distraction processing.

    PubMed

    Amer, Tarek; Ngo, K W Joan; Hasher, Lynn

    2017-05-01

    We investigated differences between participants of East Asian and Western descent in attention to and implicit memory for irrelevant words which participants were instructed to ignore while completing a target task (a Stroop Task in Experiment 1 and a 1-back task on pictures in Experiment 2). Implicit memory was measured using two conceptual priming tasks (category generation in Experiment 1 and general knowledge in Experiment 2). Participants of East Asian descent showed reliable implicit memory for previous distractors relative to those of Western descent with no evidence of differences on target task performance. We also found differences in a Corsi Block spatial memory task in both studies, with superior performance by the East Asian group. Our findings suggest that cultural differences in attention extend to task-irrelevant background information, and demonstrate for the first time that such information can boost performance when it becomes relevant on a subsequent task. © 2016 The British Psychological Society.

  11. [The effects of charity advertising on donations and donors' explicit and implicit evaluations of recipients].

    PubMed

    Kawamura, Yuta; Kusumi, Takashi

    2015-04-01

    Advertisements for charity generally employ one of two advertising strategies. The first appeals to the efficacy of support, while the second appeals to the necessity of support. Two experiments investigated the effect of each type of charity advertising on donations and on donors' explicit and implicit evaluations of the recipients. The results indicated that although participants' explicit evaluations of charity recipients were not changed by efficacy-based advertising, they were negatively influenced by necessity-based advertising. Furthermore, Experiment 1 detected moderating effects of empathic concern. The explicit evaluations of participants in the necessity-based advertising group were negatively correlated with their empathic concern. Implicit evaluations were consistently negative in both groups. Both advertising strategies were more effective at securing donations than the control group, which did not use any strategies. These findings suggest practical implications for charity advertising.

  12. The subliminal mere exposure effect does not generalize to structurally related stimuli.

    PubMed

    Newell, Ben R; Bright, James E H

    2003-03-01

    R.F. Bornstein (1994) questioned whether subliminal mere exposure effects might generalize to structurally related stimuli, thereby providing evidence for the existence of implicit learning. Two experiments examined this claim using letter string stimuli constructed according to the rules of an artificial grammar. Experiment 1 demonstrated that brief, masked exposure to grammatical strings impaired recognition but failed to produce a mere exposure effect on novel structurally related strings seen at test. Experiment 2 replicated this result but also demonstrated that a reliable mere exposure effect could be obtained, provided the same grammatical strings were presented at test. The results suggest that the structural relationship between training and test items prevents the mere exposure effect when participants are unaware of the exposure status of stimuli, and therefore provide no evidence for the existence of implicit learning.

  13. Dorsal and ventral hippocampal adult-born neurons contribute to context fear memory.

    PubMed

    Huckleberry, Kylie A; Shue, Francis; Copeland, Taylor; Chitwood, Raymond A; Yin, Weiling; Drew, Michael R

    2018-06-02

    The hippocampus contains one of the few neurogenic niches within the adult brain-the subgranular zone of the dentate gyrus. The functional significance of adult-born neurons in this region has been characterized using context fear conditioning, a Pavlovian paradigm in which animals learn to associate a location with danger. Ablation or silencing of adult-born neurons impairs both acquisition and recall of contextual fear conditioning, suggesting that these neurons contribute importantly to hippocampal memory. Lesion studies indicate that CFC depends on neural activity in both the dorsal and ventral hippocampus, subregions with unique extrahippocampal connectivity and behavioral functions. Because most studies of adult neurogenesis have relied on methods that permanently ablate neurogenesis throughout the entire hippocampus, little is known about how the function of adult-born neurons varies along the dorsal-ventral axis. Using a Nestin-CreER T2 mouse line to target the optogenetic silencer Archaerhodopsin to adult-born neurons, we compared the contribution of dorsal and ventral adult-born neurons to acquisition, recall, and generalization of CFC. Acquisition of CFC was impaired when either dorsal or ventral adult-born neurons were silenced during training. Silencing dorsal or ventral adult-born neurons during test sessions decreased context-evoked freezing but did not impair freezing in a hippocampus-independent tone-shock freezing paradigm. Silencing adult-born neurons modestly reduced generalization of fear. Our data indicate that adult-born neurons in the dorsal and ventral hippocampus contribute to both memory acquisition and recall. The comparatively large behavioral effects of silencing a small number of adult-born neurons suggest that these neurons make a unique and powerful contribution to hippocampal function.

  14. Use of implicit persuasion in decision making about adjuvant cancer treatment: A potential barrier to shared decision making.

    PubMed

    Engelhardt, Ellen G; Pieterse, Arwen H; van der Hout, Anja; de Haes, Hanneke J C J M; Kroep, Judith R; Quarles van Ufford-Mannesse, Patricia; Portielje, Johanneke E A; Smets, Ellen M A; Stiggelbout, Anne M

    2016-10-01

    Shared decision making (SDM) is widely advocated, especially for preference-sensitive decisions like those on adjuvant treatment for early-stage cancer. Here, decision making involves a subjective trade-off between benefits and side-effects, and therefore, patients' informed preferences should be taken into account. If clinicians consciously or unconsciously steer patients towards the option they think is in their patients' best interest (i.e. implicit persuasion), they may be unwittingly subverting their own efforts to implement SDM. We assessed the frequency of use of implicit persuasion during consultations and whether the use of implicit persuasion was associated with expected treatment benefit and/or decision making. Observational study design in which consecutive consultations about adjuvant systemic therapy with stage I-II breast cancer patients treated at oncology outpatient clinics of general teaching hospitals and university medical centres were audiotaped, transcribed and coded by two researchers independently. In total, 105 patients (median age = 59; range: 35-87 years) were included. A median of five (range: 2-10) implicitly persuasive behaviours were employed per consultation. The number of behaviours used did not differ by disease stage (P = 0.07), but did differ by treatment option presented (P = 0.002) and nodal status (P = 0.01). About 50% of patients with stage I or node-negative disease were steered towards undergoing chemotherapy, whereas 96% of patients were steered towards undergoing endocrine therapy, irrespective of expected treatment benefit. Decisions were less often postponed if more implicit persuasion was used (P = 0.03). Oncologists frequently use implicit persuasion, steering patients towards the treatment option that they think is in their patients' best interest. Expected treatment benefit does not always seem to be the driving force behind implicit persuasion. Awareness of one's use of these steering behaviours during decision making is a first step to help overcome the performance gap between advocating and implementing SDM. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. The effect of articulatory suppression on implicit and explicit false memory in the DRM paradigm.

    PubMed

    Van Damme, Ilse; Menten, Jan; d'Ydewalle, Gery

    2010-11-01

    Several studies have shown that reliable implicit false memory can be obtained in the DRM paradigm. There has been considerable debate, however, about whether or not conscious activation of critical lures during study is a necessary condition for this. Recent findings have revealed that articulatory suppression prevents subsequent false priming in an anagram task (Lovden & Johansson, 2003). The present experiment sought to replicate and extend these findings to an implicit word stem completion task, and to additionally investigate the effect of articulatory suppression on explicit false memory. Results showed an inhibitory effect of articulatory suppression on veridical memory, as well as on implicit false memory, whereas the level of explicit false memory was heightened. This suggests that articulatory suppression did not merely eliminate conscious lure activation, but had a more general capacity-delimiting effect. The drop in veridical memory can be attributed to diminished encoding of item-specific information. Superficial encoding also limited the spreading of semantic activation during study, which inhibited later false priming. In addition, the lack of item-specific and phenomenological details caused impaired source monitoring at test, resulting in heightened explicit false memory.

  16. Implicit aversive memory under anaesthesia in animal models: a narrative review.

    PubMed

    Samuel, N; Taub, A H; Paz, R; Raz, A

    2018-07-01

    Explicit memory after anaesthesia has gained considerable attention because of its negative implications, while implicit memory, which is more elusive and lacks patients' explicit recall, has received less attention and dedicated research. This is despite the likely impact of implicit memory on postoperative long-term well-being and behaviour. Given the scarcity of human data, fear conditioning in animals offers a reliable model of implicit learning, and importantly, one where we already have a good understanding of the underlying neural circuitry in awake conditions. Animal studies provide evidence that fear conditioning occurs under anaesthesia. The effects of different anaesthetics on memory are complex, with different drugs interacting at different stages of learning. Modulatory suppressive effects can be because of context, specific drugs, and dose dependency. In some cases, low doses of general anaesthetics can actually lead to a paradoxical opposite effect. The underlying mechanisms involve several neurotransmitter systems, acting mainly in the amygdala, hippocampus, and neocortex. Here, we review animal studies of aversive conditioning under anaesthesia, discuss the complex picture that arises, identify the gaps in knowledge that require further investigation, and highlight the potential translational relevance of the models. Copyright © 2018 British Journal of Anaesthesia. Published by Elsevier Ltd. All rights reserved.

  17. Numerical experiments with a symmetric high-resolution shock-capturing scheme

    NASA Technical Reports Server (NTRS)

    Yee, H. C.

    1986-01-01

    Characteristic-based explicit and implicit total variation diminishing (TVD) schemes for the two-dimensional compressible Euler equations have recently been developed. This is a generalization of recent work of Roe and Davis to a wider class of symmetric (non-upwind) TVD schemes other than Lax-Wendroff. The Roe and Davis schemes can be viewed as a subset of the class of explicit methods. The main properties of the present class of schemes are that they can be implicit, and, when steady-state calculations are sought, the numerical solution is independent of the time step. In a recent paper, a comparison of a linearized form of the present implicit symmetric TVD scheme with an implicit upwind TVD scheme originally developed by Harten and modified by Yee was given. Results favored the symmetric method. It was found that the latter is just as accurate as the upwind method while requiring less computational effort. Currently, more numerical experiments are being conducted on time-accurate calculations and on the effect of grid topology, numerical boundary condition procedures, and different flow conditions on the behavior of the method for steady-state applications. The purpose here is to report experiences with this type of scheme and give guidelines for its use.

  18. ASIS v1.0: an adaptive solver for the simulation of atmospheric chemistry

    NASA Astrophysics Data System (ADS)

    Cariolle, Daniel; Moinat, Philippe; Teyssèdre, Hubert; Giraud, Luc; Josse, Béatrice; Lefèvre, Franck

    2017-04-01

    This article reports on the development and tests of the adaptive semi-implicit scheme (ASIS) solver for the simulation of atmospheric chemistry. To solve the ordinary differential equation systems associated with the time evolution of the species concentrations, ASIS adopts a one-step linearized implicit scheme with specific treatments of the Jacobian of the chemical fluxes. It conserves mass and has a time-stepping module to control the accuracy of the numerical solution. In idealized box-model simulations, ASIS gives results similar to the higher-order implicit schemes derived from the Rosenbrock's and Gear's methods and requires less computation and run time at the moderate precision required for atmospheric applications. When implemented in the MOCAGE chemical transport model and the Laboratoire de Météorologie Dynamique Mars general circulation model, the ASIS solver performs well and reveals weaknesses and limitations of the original semi-implicit solvers used by these two models. ASIS can be easily adapted to various chemical schemes and further developments are foreseen to increase its computational efficiency, and to include the computation of the concentrations of the species in aqueous-phase in addition to gas-phase chemistry.

  19. Warriors and peacekeepers: testing a biosocial implicit leadership hypothesis of intergroup relations using masculine and feminine faces.

    PubMed

    Spisak, Brian R; Dekker, Peter H; Krüger, Max; van Vugt, Mark

    2012-01-01

    This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued that a biologically based hormonal connection between behavior and corresponding facial characteristics interacts with evolutionarily consistent social dynamics to influence leadership emergence. We predict that masculine-looking leaders are selected during intergroup conflict (war) and feminine-looking leaders during intergroup cooperation (peace). Across two experiments we show that a general categorization of leader versus nonleader is an initial implicit requirement for emergence, and at a context-specific level facial cues of masculinity and femininity contingently affect war versus peace leadership emergence in the predicted direction. In addition, we replicate our findings in Experiment 1 across culture using Western and East Asian samples. In Experiment 2, we also show that masculine-feminine facial cues are better predictors of leadership than male-female cues. Collectively, our results indicate a multi-level classification of context-specific leadership based on visual cues imbedded in the human face and challenge traditional distinctions of male and female leadership.

  20. Mothers' intentions to support children's physical activity related to attention and implicit agreement with advertisements.

    PubMed

    Berry, Tanya R; Craig, Cora L; Faulkner, Guy; Latimer, Amy; Rhodes, Ryan; Spence, John C; Tremblay, Mark S

    2014-02-01

    ParticipACTION's Think Again campaign targeted mothers who think their children are sufficiently active, yet whose children do not achieve recommended amounts of physical activity. This research examined the relationship of mothers' intentions to support children's physical activity with explicit believability and implicit agreement with the Think Again campaign message, attention paid to the advertisement, involvement with the issue, concern regarding children's inactivity, and attitudes. Participants were mothers from Edmonton, Canada (N = 102) who viewed one Think Again advertisement then completed a measure of implicit agreement with the campaign message and questionnaires. The mothers who paid attention to the message and were concerned for their own children were more likely to intend to act on campaign messages. The majority of participants implicitly agreed that children's physical inactivity was a problem, but there was less agreement that physical inactivity was a problem for their own children. Participants automatically tended to agree with campaign messages when the focus was on children in general, but there was greater disagreement when asked about participant's own children. Why most mothers were not in agreement with the reality of how much physical activity their children needs remains to be determined.

  1. Warriors and Peacekeepers: Testing a Biosocial Implicit Leadership Hypothesis of Intergroup Relations Using Masculine and Feminine Faces

    PubMed Central

    Spisak, Brian R.; Dekker, Peter H.; Krüger, Max; van Vugt, Mark

    2012-01-01

    This paper examines the impact of facial cues on leadership emergence. Using evolutionary social psychology, we expand upon implicit and contingent theories of leadership and propose that different types of intergroup relations elicit different implicit cognitive leadership prototypes. It is argued that a biologically based hormonal connection between behavior and corresponding facial characteristics interacts with evolutionarily consistent social dynamics to influence leadership emergence. We predict that masculine-looking leaders are selected during intergroup conflict (war) and feminine-looking leaders during intergroup cooperation (peace). Across two experiments we show that a general categorization of leader versus nonleader is an initial implicit requirement for emergence, and at a context-specific level facial cues of masculinity and femininity contingently affect war versus peace leadership emergence in the predicted direction. In addition, we replicate our findings in Experiment 1 across culture using Western and East Asian samples. In Experiment 2, we also show that masculine-feminine facial cues are better predictors of leadership than male-female cues. Collectively, our results indicate a multi-level classification of context-specific leadership based on visual cues imbedded in the human face and challenge traditional distinctions of male and female leadership. PMID:22276190

  2. Born To Read: How To Nurture a Baby's Love of Learning.

    ERIC Educational Resources Information Center

    Fiore, Carole, Comp.

    Library and health care professionals team up in the Born to Read partnerships in Florida to empower at-risk expectant and new parents to take an active role in the health and education of their children. Designed for Born to Read workshop participants, this manual contains the following sections: (1) General Information, including workshop…

  3. Preterm and term-equivalent age general movements and 1-year neurodevelopmental outcomes for infants born before 30 weeks' gestation.

    PubMed

    Olsen, Joy E; Allinson, Leesa G; Doyle, Lex W; Brown, Nisha C; Lee, Katherine J; Eeles, Abbey L; Cheong, Jeanie L Y; Spittle, Alicia J

    2018-01-01

    To examine the associations between Prechtl's General Movements Assessment (GMA), conducted from birth to term-equivalent age, and neurodevelopmental outcomes at 12 months corrected age, in infants born very preterm. One hundred and thirty-seven infants born before 30 weeks' gestation had serial GMA (categorized as 'normal' or 'abnormal') before term and at term-equivalent age. At 12 months corrected age, neurodevelopment was assessed using the Alberta Infant Motor Scale (AIMS); Neurological, Sensory, Motor, Developmental Assessment (NSMDA); and Touwen Infant Neurological Examination (TINE). The relationships between GMA at four time points and 12-month neurodevelopmental assessments were examined using regression models. Abnormal GMA at all time points were associated with worse continuous scores on the AIMS, NSMDA, and TINE (p<0.05). Abnormal GMA before term and at term-equivalent age were associated with increased odds of mild-severe dysfunction on the NSMDA (odds ratio [OR] 4.26, 95% confidence interval [CI] 1.55-11.71, p<0.01; and OR 4.16, 95% CI 1.55-11.17, p<0.01 respectively) and abnormal GMA before term with increased odds of suboptimal-abnormal motor function on the TINE (OR 2.75, 95% CI 1.10-6.85, p=0.03). Abnormal GMA before term and at term-equivalent age were associated with worse neurodevelopment at 12 months corrected age in children born very preterm. Abnormal general movements before term predict developmental deficits at 1 year in infants born very preterm. General Movements Assessment before term identifies at-risk infants born very preterm. © 2017 Mac Keith Press.

  4. Implicit face prototype learning from geometric information.

    PubMed

    Or, Charles C-F; Wilson, Hugh R

    2013-04-19

    There is evidence that humans implicitly learn an average or prototype of previously studied faces, as the unseen face prototype is falsely recognized as having been learned (Solso & McCarthy, 1981). Here we investigated the extent and nature of face prototype formation where observers' memory was tested after they studied synthetic faces defined purely in geometric terms in a multidimensional face space. We found a strong prototype effect: The basic results showed that the unseen prototype averaged from the studied faces was falsely identified as learned at a rate of 86.3%, whereas individual studied faces were identified correctly 66.3% of the time and the distractors were incorrectly identified as having been learned only 32.4% of the time. This prototype learning lasted at least 1 week. Face prototype learning occurred even when the studied faces were further from the unseen prototype than the median variation in the population. Prototype memory formation was evident in addition to memory formation of studied face exemplars as demonstrated in our models. Additional studies showed that the prototype effect can be generalized across viewpoints, and head shape and internal features separately contribute to prototype formation. Thus, implicit face prototype extraction in a multidimensional space is a very general aspect of geometric face learning. Copyright © 2013 Elsevier Ltd. All rights reserved.

  5. Ideal Gas Laws: Experiments for General Chemistry

    ERIC Educational Resources Information Center

    Deal, Walter J.

    1975-01-01

    Describes a series of experiments designed to verify the various relationships implicit in the ideal gas equation and shows that the success of the Graham's law effusion experiments can be explained by elementary hydrodynamics. (GS)

  6. Development of Different Forms of Skill Learning throughout the Lifespan

    ERIC Educational Resources Information Center

    Lukács, Ágnes; Kemény, Ferenc

    2015-01-01

    The acquisition of complex motor, cognitive, and social skills, like playing a musical instrument or mastering sports or a language, is generally associated with implicit skill learning (SL). Although it is a general view that SL is most effective in childhood, and such skills are best acquired if learning starts early, this idea has rarely been…

  7. Apprehending Mathematical Structure: A Case Study of Coming to Understand a Commutative Ring

    ERIC Educational Resources Information Center

    Simpson, Adrian; Stehlikova, Nada

    2006-01-01

    Abstract algebra courses tend to take one of two pedagogical routes: from examples of mathematics structures through definitions to general theorems, or directly from definitions to general theorems. The former route seems to be based on the implicit pedagogical intention that students will use their understanding of particular examples of an…

  8. 22 CFR 51.43 - Persons born outside the United States applying for a passport for the first time.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... for a passport for the first time. 51.43 Section 51.43 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Evidence of U.S. Citizenship or Nationality § 51.43 Persons born outside the United States applying for a passport for the first time. (a) General. A person born outside the...

  9. 22 CFR 51.43 - Persons born outside the United States applying for a passport for the first time.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... for a passport for the first time. 51.43 Section 51.43 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Evidence of U.S. Citizenship or Nationality § 51.43 Persons born outside the United States applying for a passport for the first time. (a) General. A person born outside the...

  10. 22 CFR 51.43 - Persons born outside the United States applying for a passport for the first time.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... for a passport for the first time. 51.43 Section 51.43 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Evidence of U.S. Citizenship or Nationality § 51.43 Persons born outside the United States applying for a passport for the first time. (a) General. A person born outside the...

  11. 22 CFR 51.43 - Persons born outside the United States applying for a passport for the first time.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... for a passport for the first time. 51.43 Section 51.43 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Evidence of U.S. Citizenship or Nationality § 51.43 Persons born outside the United States applying for a passport for the first time. (a) General. A person born outside the...

  12. 22 CFR 51.43 - Persons born outside the United States applying for a passport for the first time.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... for a passport for the first time. 51.43 Section 51.43 Foreign Relations DEPARTMENT OF STATE NATIONALITY AND PASSPORTS PASSPORTS Evidence of U.S. Citizenship or Nationality § 51.43 Persons born outside the United States applying for a passport for the first time. (a) General. A person born outside the...

  13. Ego depletion impairs implicit learning.

    PubMed

    Thompson, Kelsey R; Sanchez, Daniel J; Wesley, Abigail H; Reber, Paul J

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent.

  14. Ego Depletion Impairs Implicit Learning

    PubMed Central

    Thompson, Kelsey R.; Sanchez, Daniel J.; Wesley, Abigail H.; Reber, Paul J.

    2014-01-01

    Implicit skill learning occurs incidentally and without conscious awareness of what is learned. However, the rate and effectiveness of learning may still be affected by decreased availability of central processing resources. Dual-task experiments have generally found impairments in implicit learning, however, these studies have also shown that certain characteristics of the secondary task (e.g., timing) can complicate the interpretation of these results. To avoid this problem, the current experiments used a novel method to impose resource constraints prior to engaging in skill learning. Ego depletion theory states that humans possess a limited store of cognitive resources that, when depleted, results in deficits in self-regulation and cognitive control. In a first experiment, we used a standard ego depletion manipulation prior to performance of the Serial Interception Sequence Learning (SISL) task. Depleted participants exhibited poorer test performance than did non-depleted controls, indicating that reducing available executive resources may adversely affect implicit sequence learning, expression of sequence knowledge, or both. In a second experiment, depletion was administered either prior to or after training. Participants who reported higher levels of depletion before or after training again showed less sequence-specific knowledge on the post-training assessment. However, the results did not allow for clear separation of ego depletion effects on learning versus subsequent sequence-specific performance. These results indicate that performance on an implicitly learned sequence can be impaired by a reduction in executive resources, in spite of learning taking place outside of awareness and without conscious intent. PMID:25275517

  15. What predicts successful literacy acquisition in a second language?

    PubMed Central

    Frost, Ram; Siegelman, Noam; Narkiss, Alona; Afek, Liron

    2013-01-01

    We examined whether success (or failure) in assimilating the structure of a second language could be predicted by general statistical learning abilities that are non-linguistic in nature. We employed a visual statistical learning (VSL) task, monitoring our participants’ implicit learning of the transitional probabilities of visual shapes. A pretest revealed that performance in the VSL task is not correlated with abilities related to a general G factor or working memory. We found that native speakers of English who picked up the implicit statistical structure embedded in the continuous stream of shapes, on average, better assimilated the Semitic structure of Hebrew words. Our findings thus suggest that languages and their writing systems are characterized by idiosyncratic correlations of form and meaning, and these are picked up in the process of literacy acquisition, as they are picked up in any other type of learning, for the purpose of making sense of the environment. PMID:23698615

  16. Comment on "A note on generalized radial mesh generation for plasma electronic structure"

    NASA Astrophysics Data System (ADS)

    Pain, J.-Ch.

    2011-12-01

    In a recent note, B.G. Wilson and V. Sonnad [1] proposed a very useful closed form expression for the efficient generation of analytic log-linear radial meshes. The central point of the note is an implicit equation for the parameter h, involving Lambert's function W[x]. The authors mention that they are unaware of any direct proof of this equation (they obtained it by re-summing the Taylor expansion of h[α] using high-order coefficients obtained by analytic differentiation of the implicit definition using symbolic manipulation). In the present comment, we propose a direct proof of that equation.

  17. Application of fast Fourier transforms to the direct solution of a class of two-dimensional separable elliptic equations on the sphere

    NASA Technical Reports Server (NTRS)

    Moorthi, Shrinivas; Higgins, R. W.

    1993-01-01

    An efficient, direct, second-order solver for the discrete solution of a class of two-dimensional separable elliptic equations on the sphere (which generally arise in implicit and semi-implicit atmospheric models) is presented. The method involves a Fourier transformation in longitude and a direct solution of the resulting coupled second-order finite-difference equations in latitude. The solver is made efficient by vectorizing over longitudinal wave-number and by using a vectorized fast Fourier transform routine. It is evaluated using a prescribed solution method and compared with a multigrid solver and the standard direct solver from FISHPAK.

  18. Implicit solvers for unstructured meshes

    NASA Technical Reports Server (NTRS)

    Venkatakrishnan, V.; Mavriplis, Dimitri J.

    1991-01-01

    Implicit methods for unstructured mesh computations are developed and tested. The approximate system which arises from the Newton-linearization of the nonlinear evolution operator is solved by using the preconditioned generalized minimum residual technique. These different preconditioners are investigated: the incomplete LU factorization (ILU), block diagonal factorization, and the symmetric successive over-relaxation (SSOR). The preconditioners have been optimized to have good vectorization properties. The various methods are compared over a wide range of problems. Ordering of the unknowns, which affects the convergence of these sparse matrix iterative methods, is also investigated. Results are presented for inviscid and turbulent viscous calculations on single and multielement airfoil configurations using globally and adaptively generated meshes.

  19. Addressing Implicit Bias to Improve Cross-cultural Care.

    PubMed

    Pereda, Brenda; Montoya, Margaret

    2018-03-01

    Health disparities cluster around race, ethnicity, education, neighborhoods, and income. Systems of exclusion that correlate with social determinants compound the disproportionate burden of poor health experienced by people of color. By 2056, ~50% of the population is expected to fall into categories currently labeled "under-represented minorities" (URMs), primarily African Americans, Latinxs, and American Indians. Although URMs comprise 30% of the general population, only 9% of medical doctors [Association of American Medical Colleges (AAMC)] are URMs. We can lessen the negative effects of implicit bias and minimize inequities and unequal treatment by medical providers with training in cross-disciplinary diversity knowledge and communication skills.

  20. The Born-Infeld vortices induced from a generalized Higgs mechanism.

    PubMed

    Han, Xiaosen

    2016-04-01

    We construct self-dual Born-Infeld vortices induced from a generalized Higgs mechanism. Two specific models of the theory are of focused interest where the Higgs potential is either of a | ϕ | 4 - or | ϕ | 6 -type. For the | ϕ | 4 -model, we obtain a sharp existence and uniqueness theorem for doubly periodic and planar vortices. For doubly periodic solutions, a necessary and sufficient condition for the existence is explicitly derived in terms of the vortex number, the Born-Infeld parameter, and the size of the periodic lattice domain. For the | ϕ | 6 -model, we show that both topological and non-topological vortices are present. This new phenomenon distinguishes the model from the classical Born-Infeld-Higgs theory studied earlier in the literature. A series of results regarding doubly periodic, topological, and non-topological vortices in the | ϕ | 6 -model are also established.

  1. Collaborative Calculus.

    ERIC Educational Resources Information Center

    Kast, David

    1993-01-01

    The crisis confronting calculus and mathematics education generally results from a number of failed assumptions implicit in the dominant lecture-homework-exam methodology used in teaching mathematics. Positive resolution of this crisis can be found in adopting a noncompetitive, collaborative approach to mathematics education. (Author)

  2. Does the Hispanic Paradox in U.S. Adult Mortality Extend to Disability?

    PubMed Central

    Hummer, Robert A.; Chiu, Chi-Tsun; González-González, César; Wong, Rebeca

    2015-01-01

    Studies consistently document a Hispanic paradox in U.S. adult mortality, whereby Hispanics have similar or lower mortality rates than non-Hispanic whites despite lower socioeconomic status. This study extends this line of inquiry to disability, especially among foreign-born Hispanics, since their advantaged mortality seemingly should be paired with health advantages more generally. We also assess whether the paradox extends to U.S.-born Hispanics to evaluate the effect of nativity. We calculate multistate life tables of life expectancy with disability to assess whether racial/ethnic and nativity differences in the length of disability-free life parallel differences in overall life expectancy. Our results document a Hispanic paradox in mortality for foreign-born and U.S.-born Hispanics. However, Hispanics’ low mortality rates are not matched by low disability rates. Their disability rates are substantially higher than those of non-Hispanic whites and generally similar to those of non-Hispanic blacks. The result is a protracted period of disabled life expectancy for Hispanics, both foreign- and U.S.-born. PMID:25821283

  3. The association between tobacco, alcohol, and drug use, stress, and depression among uninsured free clinic patients: U.S.-born English speakers, non-U.S.-born English speakers, and Spanish speakers.

    PubMed

    Kamimura, Akiko; Ashby, Jeanie; Tabler, Jennifer; Nourian, Maziar M; Trinh, Ha Ngoc; Chen, Jason; Reel, Justine J

    2017-01-01

    The abuse of substances is a significant public health issue. Perceived stress and depression have been found to be related to the abuse of substances. The purpose of this study is to examine the prevalence of substance use (i.e., alcohol problems, smoking, and drug use) and the association between substance use, perceived stress, and depression among free clinic patients. Patients completed a self-administered survey in 2015 (N = 504). The overall prevalence of substance use among free clinic patients was not high compared to the U.S. general population. U.S.-born English speakers reported a higher prevalence rate of tobacco smoking and drug use than did non-U.S.-born English speakers and Spanish speakers. Alcohol problems and smoking were significantly related to higher levels of perceived stress and depression. Substance use prevention and education should be included in general health education programs. U.S.-born English speakers would need additional attention. Mental health intervention would be essential to prevention and intervention.

  4. Mixed time integration methods for transient thermal analysis of structures

    NASA Technical Reports Server (NTRS)

    Liu, W. K.

    1982-01-01

    The computational methods used to predict and optimize the thermal structural behavior of aerospace vehicle structures are reviewed. In general, two classes of algorithms, implicit and explicit, are used in transient thermal analysis of structures. Each of these two methods has its own merits. Due to the different time scales of the mechanical and thermal responses, the selection of a time integration method can be a different yet critical factor in the efficient solution of such problems. Therefore mixed time integration methods for transient thermal analysis of structures are being developed. The computer implementation aspects and numerical evaluation of these mixed time implicit-explicit algorithms in thermal analysis of structures are presented. A computationally useful method of estimating the critical time step for linear quadrilateral element is also given. Numerical tests confirm the stability criterion and accuracy characteristics of the methods. The superiority of these mixed time methods to the fully implicit method or the fully explicit method is also demonstrated.

  5. Mixed time integration methods for transient thermal analysis of structures

    NASA Technical Reports Server (NTRS)

    Liu, W. K.

    1983-01-01

    The computational methods used to predict and optimize the thermal-structural behavior of aerospace vehicle structures are reviewed. In general, two classes of algorithms, implicit and explicit, are used in transient thermal analysis of structures. Each of these two methods has its own merits. Due to the different time scales of the mechanical and thermal responses, the selection of a time integration method can be a difficult yet critical factor in the efficient solution of such problems. Therefore mixed time integration methods for transient thermal analysis of structures are being developed. The computer implementation aspects and numerical evaluation of these mixed time implicit-explicit algorithms in thermal analysis of structures are presented. A computationally-useful method of estimating the critical time step for linear quadrilateral element is also given. Numerical tests confirm the stability criterion and accuracy characteristics of the methods. The superiority of these mixed time methods to the fully implicit method or the fully explicit method is also demonstrated.

  6. Ethnic variation in gender-STEM stereotypes and STEM participation: an intersectional approach.

    PubMed

    O'Brien, Laurie T; Blodorn, Alison; Adams, Glenn; Garcia, Donna M; Hammer, Elliott

    2015-04-01

    Stereotypes associating men and masculine traits with science, technology, engineering, and mathematics (STEM) fields are ubiquitous, but the relative strength of these stereotypes varies considerably across cultures. The present research applies an intersectional approach to understanding ethnic variation in gender-STEM stereotypes and STEM participation within an American university context. African American college women participated in STEM majors at higher rates than European American college women (Study 1, Study 2, and Study 4). Furthermore, African American women had weaker implicit gender-STEM stereotypes than European American women (Studies 2-4), and ethnic differences in implicit gender-STEM stereotypes partially mediated ethnic differences in STEM participation (Study 2 and Study 4). Although African American men had weaker implicit gender-STEM stereotypes than European American men (Study 4), ethnic differences between men in STEM participation were generally small (Study 1) or nonsignificant (Study 4). We discuss the implications of an intersectional approach for understanding the relationship between gender and STEM participation. (c) 2015 APA, all rights reserved).

  7. Multigrid calculation of three-dimensional turbomachinery flows

    NASA Technical Reports Server (NTRS)

    Caughey, David A.

    1989-01-01

    Research was performed in the general area of computational aerodynamics, with particular emphasis on the development of efficient techniques for the solution of the Euler and Navier-Stokes equations for transonic flows through the complex blade passages associated with turbomachines. In particular, multigrid methods were developed, using both explicit and implicit time-stepping schemes as smoothing algorithms. The specific accomplishments of the research have included: (1) the development of an explicit multigrid method to solve the Euler equations for three-dimensional turbomachinery flows based upon the multigrid implementation of Jameson's explicit Runge-Kutta scheme (Jameson 1983); (2) the development of an implicit multigrid scheme for the three-dimensional Euler equations based upon lower-upper factorization; (3) the development of a multigrid scheme using a diagonalized alternating direction implicit (ADI) algorithm; (4) the extension of the diagonalized ADI multigrid method to solve the Euler equations of inviscid flow for three-dimensional turbomachinery flows; and also (5) the extension of the diagonalized ADI multigrid scheme to solve the Reynolds-averaged Navier-Stokes equations for two-dimensional turbomachinery flows.

  8. Multiscale Failure Analysis of Laminated Composite Panels Subjected to Blast Loading Using FEAMAC/Explicit

    NASA Technical Reports Server (NTRS)

    Pineda, Evan J.; Waas, Anthony M.; Berdnarcyk, Brett A.; Arnold, Steven M.; Collier, Craig S.

    2009-01-01

    This preliminary report demonstrates the capabilities of the recently developed software implementation that links the Generalized Method of Cells to explicit finite element analysis by extending a previous development which tied the generalized method of cells to implicit finite elements. The multiscale framework, which uses explicit finite elements at the global-scale and the generalized method of cells at the microscale is detailed. This implementation is suitable for both dynamic mechanics problems and static problems exhibiting drastic and sudden changes in material properties, which often encounter convergence issues with commercial implicit solvers. Progressive failure analysis of stiffened and un-stiffened fiber-reinforced laminates subjected to normal blast pressure loads was performed and is used to demonstrate the capabilities of this framework. The focus of this report is to document the development of the software implementation; thus, no comparison between the results of the models and experimental data is drawn. However, the validity of the results are assessed qualitatively through the observation of failure paths, stress contours, and the distribution of system energies.

  9. Submentalizing or Mentalizing in a Level 1 Perspective-Taking Task: A Cloak and Goggles Test

    PubMed Central

    2016-01-01

    It has been proposed that humans possess an automatic system to represent mental states (‘implicit mentalizing’). The existence of an implicit mentalizing system has generated considerable debate however, centered on the ability of various experimental paradigms to demonstrate unambiguously such mentalizing. Evidence for implicit mentalizing has previously been provided by the ‘dot perspective task,’ where participants are slower to verify the number of dots they can see when an avatar can see a different number of dots. However, recent evidence challenged a mentalizing interpretation of this effect by showing it was unaltered when the avatar was replaced with an inanimate arrow stimulus. Here we present an extension of the dot perspective task using an invisibility cloaking device to render the dots invisible on certain trials. This paradigm is capable of providing unambiguous evidence of automatic mentalizing, but no such evidence was found. Two further well-powered experiments used opaque and transparent goggles to manipulate visibility but found no evidence of automatic mentalizing, nor of individual differences in empathy or perspective-taking predicting performance, contradicting previous studies using the same design. The results cast doubt on the existence of an implicit mentalizing system, suggesting that previous effects were due to domain-general processes. PMID:27893269

  10. Biogenetic models of psychopathology, implicit guilt, and mental illness stigma.

    PubMed

    Rüsch, Nicolas; Todd, Andrew R; Bodenhausen, Galen V; Corrigan, Patrick W

    2010-10-30

    Whereas some research suggests that acknowledgment of the role of biogenetic factors in mental illness could reduce mental illness stigma by diminishing perceived responsibility, other research has cautioned that emphasizing biogenetic aspects of mental illness could produce the impression that mental illness is a stable, intrinsic aspect of a person ("genetic essentialism"), increasing the desire for social distance. We assessed genetic and neurobiological causal attributions about mental illness among 85 people with serious mental illness and 50 members of the public. The perceived responsibility of persons with mental illness for their condition, as well as fear and social distance, was assessed by self-report. Automatic associations between Mental Illness and Guilt and between Self and Guilt were measured by the Brief Implicit Association Test. Among the general public, endorsement of biogenetic models was associated with not only less perceived responsibility, but also greater social distance. Among people with mental illness, endorsement of genetic models had only negative correlates: greater explicit fear and stronger implicit self-guilt associations. Genetic models may have unexpected negative consequences for implicit self-concept and explicit attitudes of people with serious mental illness. An exclusive focus on genetic models may therefore be problematic for clinical practice and anti-stigma initiatives. Copyright © 2009 Elsevier Ltd. All rights reserved.

  11. Reflective Random Indexing and indirect inference: a scalable method for discovery of implicit connections.

    PubMed

    Cohen, Trevor; Schvaneveldt, Roger; Widdows, Dominic

    2010-04-01

    The discovery of implicit connections between terms that do not occur together in any scientific document underlies the model of literature-based knowledge discovery first proposed by Swanson. Corpus-derived statistical models of semantic distance such as Latent Semantic Analysis (LSA) have been evaluated previously as methods for the discovery of such implicit connections. However, LSA in particular is dependent on a computationally demanding method of dimension reduction as a means to obtain meaningful indirect inference, limiting its ability to scale to large text corpora. In this paper, we evaluate the ability of Random Indexing (RI), a scalable distributional model of word associations, to draw meaningful implicit relationships between terms in general and biomedical language. Proponents of this method have achieved comparable performance to LSA on several cognitive tasks while using a simpler and less computationally demanding method of dimension reduction than LSA employs. In this paper, we demonstrate that the original implementation of RI is ineffective at inferring meaningful indirect connections, and evaluate Reflective Random Indexing (RRI), an iterative variant of the method that is better able to perform indirect inference. RRI is shown to lead to more clearly related indirect connections and to outperform existing RI implementations in the prediction of future direct co-occurrence in the MEDLINE corpus. 2009 Elsevier Inc. All rights reserved.

  12. Non-interpretive mechanisms in psychoanalytic therapy. The 'something more' than interpretation. The Process of Change Study Group.

    PubMed

    Stern, D N; Sander, L W; Nahum, J P; Harrison, A M; Lyons-Ruth, K; Morgan, A C; Bruschweiler-Stern, N; Tronick, E Z

    1998-10-01

    It is by now generally accepted that something more than interpretation is necessary to bring about therapeutic change. Using an approach based on recent studies of mother-infant interaction and non-linear dynamic systems and their relation to theories of mind, the authors propose that the something more resides in interactional intersubjective process that give rise to what they will call 'implicit relational knowing'. This relational procedural domain is intrapsychically distinct from the symbolic domain. In the analytic relationship it comprises intersubjective moments occurring between patient and analyst that can create new organisations in, or reorganise not only the relationship between the interactants, but more importantly the patient's implicit procedural knowledge, his ways of being with others. The distinct qualities and consequences of these moments (now moments, 'moments of meeting') are modelled and discussed in terms of a sequencing process that they call moving along. Conceptions of the shared implicit relationship, transference and countertransference are discussed within the parameters of this perspective, which is distinguished from other relational theories and self-psychology. In sum, powerful therapeutic action occurs within implicit relational knowledge. They propose that much of what is observed to be lasting therapeutic effect results from such changes in this intersubjective relational domain.

  13. Evidence that implicit assumptions of ‘no evolution’ of disease vectors in changing environments can be violated on a rapid timescale

    PubMed Central

    Egizi, Andrea; Fefferman, Nina H.; Fonseca, Dina M.

    2015-01-01

    Projected impacts of climate change on vector-borne disease dynamics must consider many variables relevant to hosts, vectors and pathogens, including how altered environmental characteristics might affect the spatial distributions of vector species. However, many predictive models for vector distributions consider their habitat requirements to be fixed over relevant time-scales, when they may actually be capable of rapid evolutionary change and even adaptation. We examine the genetic signature of a spatial expansion by an invasive vector into locations with novel temperature conditions compared to its native range as a proxy for how existing vector populations may respond to temporally changing habitat. Specifically, we compare invasions into different climate ranges and characterize the importance of selection from the invaded habitat. We demonstrate that vector species can exhibit evolutionary responses (altered allelic frequencies) to a temperature gradient in as little as 7–10 years even in the presence of high gene flow, and further, that this response varies depending on the strength of selection. We interpret these findings in the context of climate change predictions for vector populations and emphasize the importance of incorporating vector evolution into models of future vector-borne disease dynamics. PMID:25688024

  14. Early Indications of Delayed Cognitive Development in Preschool Children Born Very Preterm: Evidence from Domain-General and Domain-Specific Tasks

    ERIC Educational Resources Information Center

    Pitchford, Nicola; Johnson, Samantha; Scerif, Gaia; Marlow, Neil

    2011-01-01

    Cognitive impairment often follows preterm birth but its early underlying nature is not well understood. We used a novel approach by investigating the development of colour cognition in 54 very preterm children born less than or equal to 30 weeks gestational age without severe neurosensory impairment and 37 age-matched term-born controls, aged 2-5…

  15. Psychological and Biological Validation of a Novel Digital Social Peer Evaluation Experiment (digi-SPEE).

    PubMed

    Menne-Lothmann, Claudia; Decoster, Jeroen; van Winkel, Ruud; Collip, Dina; Rutten, Bart P F; Delespaul, Philippe; De Hert, Marc; Derom, Catherine; Thiery, Evert; Jacobs, Nele; van Os, Jim; Wichers, Marieke

    2017-03-01

    Negative social evaluation is associated with psychopathology. Given the frequency of evaluation through increasingly prevalent virtual social networks, increased understanding of the effects of this social evaluation is urgently required. A new digital social peer evaluation experiment (digi-SPEE) was developed to mimic everyday online social interactions between peers. Participants received mildly negative feedback on their appearance, intelligence, and congeniality. Two hundred and forty-one young people [58.9% female, aged 18.9 years (15 to 34)] from an ongoing novel general population twin study participated in this study. Positive affect (PA), negative affect (NA), implicit self-esteem, and cortisol were assessed before and after exposure to the social evaluation experiment. The social evaluation experiment decreased PA (B=-5.25, p<.001) and implicit self-esteem (B=-.19; p<.001), whereas it increased NA (B=5.99; p<.001) and cortisol levels (B=.07; p<.001). Females (PA: B=-7.62; p<.001; NA: B=8.28; p<.001) and participants with higher levels of general psychological distress (PA: B=-.04, p=.035; NA: B=.06; p=.028) showed stronger affective responses. Stressor-induced cortisol increase was stronger in adolescents under the age of 18 than in participants 18 years and older (B=-.06, p=.002). The digi-SPEE represents a social evaluation stressor that elicits biological and implicit and explicit mental changes that are relevant to mechanisms of psychopathology.

  16. Coherent states, quantum gravity, and the Born-Oppenheimer approximation. I. General considerations

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

    Stottmeister, Alexander, E-mail: alexander.stottmeister@gravity.fau.de; Thiemann, Thomas, E-mail: thomas.thiemann@gravity.fau.de

    2016-06-15

    This article, as the first of three, aims at establishing the (time-dependent) Born-Oppenheimer approximation, in the sense of space adiabatic perturbation theory, for quantum systems constructed by techniques of the loop quantum gravity framework, especially the canonical formulation of the latter. The analysis presented here fits into a rather general framework and offers a solution to the problem of applying the usual Born-Oppenheimer ansatz for molecular (or structurally analogous) systems to more general quantum systems (e.g., spin-orbit models) by means of space adiabatic perturbation theory. The proposed solution is applied to a simple, finite dimensional model of interacting spin systems,more » which serves as a non-trivial, minimal model of the aforesaid problem. Furthermore, it is explained how the content of this article and its companion affect the possible extraction of quantum field theory on curved spacetime from loop quantum gravity (including matter fields).« less

  17. Generalized Born Models of Macromolecular Solvation Effects

    NASA Astrophysics Data System (ADS)

    Bashford, Donald; Case, David A.

    2000-10-01

    It would often be useful in computer simulations to use a simple description of solvation effects, instead of explicitly representing the individual solvent molecules. Continuum dielectric models often work well in describing the thermodynamic aspects of aqueous solvation, and approximations to such models that avoid the need to solve the Poisson equation are attractive because of their computational efficiency. Here we give an overview of one such approximation, the generalized Born model, which is simple and fast enough to be used for molecular dynamics simulations of proteins and nucleic acids. We discuss its strengths and weaknesses, both for its fidelity to the underlying continuum model and for its ability to replace explicit consideration of solvent molecules in macromolecular simulations. We focus particularly on versions of the generalized Born model that have a pair-wise analytical form, and therefore fit most naturally into conventional molecular mechanics calculations.

  18. The impact of migration on deaths and hospital admissions from work-related injuries in Australia.

    PubMed

    Reid, Alison; Peters, Susan; Felipe, Nieves; Lenguerrand, Erik; Harding, Seeromanie

    2016-02-01

    The shift from an industrial to a service-based economy has seen a decline in work-related injuries (WRIs) and mortality. How this relates to migrant workers, who traditionally held high-risk jobs is unknown. This study examined deaths and hospital admissions from WRI, among foreign and Australian-born workers. Tabulated population data from the 1991 to 2011 censuses, national deaths 1991-2002 and hospital admission for 2001-10. Direct age standardised mortality and hospital admission rates (DSRs) and rate ratios (RRs) were derived to examine differences in work-related mortality/hospital admissions by gender, country of birth, employment skill level and years of residence in Australia. DSRs and RRs were generally lower or no different between Australian and foreign-born workers. Among men, mortality DSRs were lower for nine of 16 country of birth groups, and hospital admissions DSRs for 14 groups. An exception was New Zealand-born men, with 9% (95%CI 9-13) excess mortality and 24% (95%CI 22-26) excess hospital admissions. Four decades ago, foreign-born workers were generally at higher risk of WRI than Australian-born. This pattern has reversed. The local-born comprise 75% of the population and a pro-active approach to health and safety regulation could achieve large benefits. © 2015 Public Health Association of Australia.

  19. On dynamic prices: a clash of beliefs?

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

    Hanser, Philip Q

    2010-07-15

    While insightful essays have been written regarding the moral appropriateness of dynamic pricing, they have an implicit underlying framework for determining justness and fairness that may not necessarily accord completely with the view promulgated in regard to utility rate setting generally. (author)

  20. Oppositions

    ERIC Educational Resources Information Center

    Spindler, George; Spindler, Louise

    1984-01-01

    Sees Dobbert et al's model of cultural transmission (this issue) as generalizing, structural, mechanical, predetermined, formal, digital, and etic. Posits an alternative approach that is idiographic, processual, organic, open, nonformal, analogical, and attentive to emic data. Argues that the Dobbert model accounts inadequately for the implicit,…

  1. [Characteristics and health status of homeless women born in France and abroad: Results of Insee-Ined 2012 survey].

    PubMed

    Gomes do Espirito Santo, M-E; Perrine, A-L; Bonaldi, C; Guseva-Canu, I

    2018-03-01

    French national surveys among the homeless population in 2001 and 2012 provided a general description of the homeless beneficiaries of medical and social aids. However, given the increasing number of women in this population, mostly born abroad and accompanied by their children, a descriptive study of homeless women according to the fact of being born in France or abroad was conducted. A probability sample of 1470 French-speaking homeless women was recruited for the Insee-Ined 2012 survey. Socio-demographic characteristics, life trajectories, work and employment over the last 12 months, perceived health, reported morbidity, use of care and medical coverage have been described, comparing homeless women born abroad with those born in France. Homeless women are young (median age=34 y.), often single (55%), without a partner (71%) and often accompanied by children (52%). The vast majority (60%) reported no salary during the previous 12 months. Housing conditions were less precarious in women born in France, but these women had a more difficult life history, a more unfavorable perception of their health status, and a higher frequency of chronic health problems. Homeless women born abroad seemed to have more precarious conditions of life and more difficulties to access aids and medical coverage. Overall, despite a relatively good availability of medical insurance, homeless women, regardless of the place of birth, often reported health problems, which were not treated. This study suggests that homeless women often have to deal with chronic health problems that are not treated. Homeless women born abroad are characterized by more precarious living conditions that women born in France. Although younger, with an overall favorable perception of their health and declaring less often an addiction, their general state of health appears to be as fragile as for women born in France. Actions towards homeless women should be implemented to promote their access to care. Copyright © 2017. Published by Elsevier Masson SAS.

  2. Unstable density distribution associated with equatorial plasma bubble

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

    Kherani, E. A., E-mail: esfhan.kherani@inpe.br; Meneses, F. Carlos de; Bharuthram, R.

    2016-04-15

    In this work, we present a simulation study of equatorial plasma bubble (EPB) in the evening time ionosphere. The fluid simulation is performed with a high grid resolution, enabling us to probe the steepened updrafting density structures inside EPB. Inside the density depletion that eventually evolves as EPB, both density and updraft are functions of space from which the density as implicit function of updraft velocity or the density distribution function is constructed. In the present study, this distribution function and the corresponding probability distribution function are found to evolve from Maxwellian to non-Maxwellian as the initial small depletion growsmore » to EPB. This non-Maxwellian distribution is of a gentle-bump type, in confirmation with the recently reported distribution within EPB from space-borne measurements that offer favorable condition for small scale kinetic instabilities.« less

  3. Nonverbal Behavior in Speech Acts.

    ERIC Educational Resources Information Center

    Key, Mary Ritchie

    In forming a theory of communicative interaction between human beings it is necessary to consider some general features implicit in the communicative process. These include the context of situation, philosophical categories, psycholinguistic categories, grammatical categories, and nonverbal categories. Most of these are extra-linguistic and have…

  4. Generalized extended Lagrangian Born-Oppenheimer molecular dynamics

    DOE PAGES

    Niklasson, Anders M. N.; Cawkwell, Marc J.

    2014-10-29

    Extended Lagrangian Born-Oppenheimer molecular dynamics based on Kohn-Sham density functional theory is generalized in the limit of vanishing self-consistent field optimization prior to the force evaluations. The equations of motion are derived directly from the extended Lagrangian under the condition of an adiabatic separation between the nuclear and the electronic degrees of freedom. We show how this separation is automatically fulfilled and system independent. The generalized equations of motion require only one diagonalization per time step and are applicable to a broader range of materials with improved accuracy and stability compared to previous formulations.

  5. West nile virus and equine encephalitis viruses: new perspectives.

    PubMed

    Long, Maureen T

    2014-12-01

    Mosquito-borne diseases affect horses worldwide. Mosquito-borne diseases generally cause encephalomyelitis in the horse and can be difficult to diagnose antemortem. In addition to general disease, and diagnostic and treatment aspects, this review article summarizes the latest information on these diseases, covering approximately the past 5 years, with a focus on new equine disease encroachments, diagnostic and vaccination aspects, and possible therapeutics on the horizon. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Down Syndrome: Gestational Age-Related Neonatal Anthropometrics for Germany.

    PubMed

    Hoffmann, Paul F; Jung, Anna-Maria; Stierkorb, Eva; Monz, Dominik; Gortner, Ludwig; Rohrer, Tilman R

    2016-01-01

    Neonates with Down syndrome (DS) weigh less, are smaller and have increased first-year mortality, especially if born small for gestational age (GA). DS-specific GA-related neonatal anthropometrics for Germany are lacking. To construct reference tables and centile curves for birth weight (g), crown-heel length (cm) and head circumference (cm) by sex and GA for German DS neonates. Retrospective anthropometric data from live-born singleton DS neonates born in Germany from January 1966 to June 2010 were collected using standardized questionnaires and patient records. Reference tables were created based on means and standard deviations. The 3rd, 10th, 25th, 50th, 75th, 90th and 97th centile curves were constructed and smoothed using running medians and Cole's LMS method. Anthropometric measurements were obtained for 1,304 DS neonates [males/females: 713/591 (54.7%/45.3%)]. Reference tables and centile charts were constructed from 3,542 (males/females: 1,932/1,610) observations for GA 32-41 weeks. Compared with general-population newborns, prematurity was increased (21.1 vs. 6.3%) at GA 32-36 weeks. Term-born (GA 40 weeks) male and female DS neonates were 352.5 and 223.5 g lighter and 1.5 and 1.4 cm smaller than general-population neonates, and head circumference was also 1.4 and 1.5 cm smaller, respectively. This is the first study to report GA-related, sex-specific reference tables and centile charts of birth weight, length and head circumference for DS neonates born in Germany. Compared with the general German population, DS newborns are more frequently born prematurely, weigh less, are smaller and have a smaller head circumference at birth. © 2016 S. Karger AG, Basel.

  7. Gender differences in memory for objects and their locations: a study on automatic versus controlled encoding and retrieval contexts.

    PubMed

    De Goede, Maartje; Postma, Albert

    2008-04-01

    Object-location memory is the only spatial task where female subjects have been shown to outperform males. This result is not consistent across all studies, and may be due to the combination of the multi-component structure of object location memory with the conditions under which different studies were done. Possible gender differences in object location memory and its component object identity memory were assessed in the present study. In order to disentangle these two components, an object location memory task (in which objects had to be relocated in daily environments), and a separate object identity recognition task were carried out. This study also focused on the conditions under which object locations were encoded and retrieved. Only half of the participants were aware of the fact that object locations had to be retrieved later on. Moreover, by applying the 'process dissociation procedure' to the object location memory assessments and the 'remember-know' paradigm to the object identity measure, the amount of explicit (conscious) and implicit (unconscious) retrieval was estimated for each component. In general, females performed better than males on the object location memory task. However, when controlled for object identity memory, females no longer outperformed males, whereas they did not obtain a higher general object identity memory score, nor did they have more explicit or implicit recollection of the object identities. These complicated effects might stem from a difference between males and females, in the way locations or associations between objects and locations are retrieved. In general, participants had more explicit (conscious) recollection than implicit (unconscious) recollection. No effect of encoding context was found, nor any interaction effect of gender, encoding and retrieval context.

  8. 75 FR 39462 - Conservatorship and Receivership

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-09

    ... Act to make explicit FHFA's general regulatory and supervisory authority. To this end, section 1311(b... functions of the regulated entity consistent with appointment as conservator or receiver; and (4) preserve.... Second, the Enterprises were supported for many years by the implicit federal guarantee, which enabled...

  9. A general approach to the testing of binary solubility systems for thermodynamic consistency. Consolidated Fuel Reprocessing Program

    NASA Astrophysics Data System (ADS)

    Hamm, L. L.; Vanbrunt, V.

    1982-08-01

    The numerical solution to the ordinary differential equation which describes the high-pressure vapor-liquid equilibria of a binary system where one of the components is supercritical and exists as a noncondensable gas in the pure state is considered with emphasis on the implicit Runge-Kuta and orthogonal collocation methods. Some preliminary results indicate that the implicit Runge-Kutta method is superior. Due to the extreme nonlinearity of thermodynamic properties in the region near the critical locus, and extended cubic spline fitting technique is devised for correlating the P-x data. The least-squares criterion is employed in smoothing the experimental data. The technique could easily be applied to any thermodynamic data by changing the endpoint requirements. The volumetric behavior of the systems must be given or predicted in order to perform thermodynamic consistency tests. A general procedure is developed for predicting the volumetric behavior required and some indication as to the expected limit of accuracy is given.

  10. An implicit theory of self-esteem: the consequences of perceived self-esteem for romantic desirability.

    PubMed

    Zeigler-Hill, Virgil; Myers, Erin M

    2011-04-07

    The provision of information appears to be an important property of self-esteem as evidenced by previous research concerning the status-tracking and status-signaling models of self-esteem. The present studies examine whether there is an implicit theory of self-esteem that leads individuals to assume targets with higher levels of self-esteem possess more desirable characteristics than those with lower levels of self-esteem. Across 6 studies, targets with ostensibly higher levels of self-esteem were generally rated as more attractive and as more desirable relationship partners than those with lower levels of self- esteem. It is important to note, however, that this general trend did not consistently emerge for female targets. Rather, female targets with high self-esteem were often evaluated less positively than those with more moderate levels of self-esteem. The present findings are discussed in the context of an extended informational model of self-esteem consisting of both the status-tracking and status-signaling properties of self-esteem.

  11. Sleep underpins the plasticity of language production.

    PubMed

    Gaskell, M Gareth; Warker, Jill; Lindsay, Shane; Frost, Rebecca; Guest, James; Snowdon, Reza; Stackhouse, Abigail

    2014-07-01

    The constraints that govern acceptable phoneme combinations in speech perception and production have considerable plasticity. We addressed whether sleep influences the acquisition of new constraints and their integration into the speech-production system. Participants repeated sequences of syllables in which two phonemes were artificially restricted to syllable onset or syllable coda, depending on the vowel in that sequence. After 48 sequences, participants either had a 90-min nap or remained awake. Participants then repeated 96 sequences so implicit constraint learning could be examined, and then were tested for constraint generalization in a forced-choice task. The sleep group, but not the wake group, produced speech errors at test that were consistent with restrictions on the placement of phonemes in training. Furthermore, only the sleep group generalized their learning to new materials. Polysomnography data showed that implicit constraint learning was associated with slow-wave sleep. These results show that sleep facilitates the integration of new linguistic knowledge with existing production constraints. These data have relevance for systems-consolidation models of sleep. © The Author(s) 2014.

  12. Subtle Implicit Language Facts Emerge from the Functions of Constructions

    PubMed Central

    Goldberg, Adele E.

    2016-01-01

    Much has been written about the unlikelihood of innate, syntax-specific, universal knowledge of language (Universal Grammar) on the grounds that it is biologically implausible, unresponsive to cross-linguistic facts, theoretically inelegant, and implausible and unnecessary from the perspective of language acquisition. While relevant, much of this discussion fails to address the sorts of facts that generative linguists often take as evidence in favor of the Universal Grammar Hypothesis: subtle, intricate, knowledge about language that speakers implicitly know without being taught. This paper revisits a few often-cited such cases and argues that, although the facts are sometimes even more complex and subtle than is generally appreciated, appeals to Universal Grammar fail to explain the phenomena. Instead, such facts are strongly motivated by the functions of the constructions involved. The following specific cases are discussed: (a) the distribution and interpretation of anaphoric one, (b) constraints on long-distance dependencies, (c) subject-auxiliary inversion, and (d) cross-linguistic linking generalizations between semantics and syntax. PMID:26858662

  13. A class of high resolution explicit and implicit shock-capturing methods

    NASA Technical Reports Server (NTRS)

    Yee, H. C.

    1989-01-01

    An attempt is made to give a unified and generalized formulation of a class of high resolution, explicit and implicit shock capturing methods, and to illustrate their versatility in various steady and unsteady complex shock wave computations. Included is a systematic review of the basic design principle of the various related numerical methods. Special emphasis is on the construction of the basis nonlinear, spatially second and third order schemes for nonlinear scalar hyperbolic conservation laws and the methods of extending these nonlinear scalar schemes to nonlinear systems via the approximate Riemann solvers and the flux vector splitting approaches. Generalization of these methods to efficiently include equilibrium real gases and large systems of nonequilibrium flows are discussed. Some issues concerning the applicability of these methods that were designed for homogeneous hyperbolic conservation laws to problems containing stiff source terms and shock waves are also included. The performance of some of these schemes is illustrated by numerical examples for 1-, 2- and 3-dimensional gas dynamics problems.

  14. Discontinuous categories affect information-integration but not rule-based category learning.

    PubMed

    Maddox, W Todd; Filoteo, J Vincent; Lauritzen, J Scott; Connally, Emily; Hejl, Kelli D

    2005-07-01

    Three experiments were conducted that provide a direct examination of within-category discontinuity manipulations on the implicit, procedural-based learning and the explicit, hypothesis-testing systems proposed in F. G. Ashby, L. A. Alfonso-Reese, A. U. Turken, and E. M. Waldron's (1998) competition between verbal and implicit systems model. Discontinuous categories adversely affected information-integration but not rule-based category learning. Increasing the magnitude of the discontinuity did not lead to a significant decline in performance. The distance to the bound provides a reasonable description of the generalization profile associated with the hypothesis-testing system, whereas the distance to the bound plus the distance to the trained response region provides a reasonable description of the generalization profile associated with the procedural-based learning system. These results suggest that within-category discontinuity differentially impacts information-integration but not rule-based category learning and provides information regarding the detailed processing characteristics of each category learning system. ((c) 2005 APA, all rights reserved).

  15. The association of children's mathematic abilities with both adults' cognitive abilities and intrinsic fronto-parietal networks is altered in preterm-born individuals.

    PubMed

    Bäuml, J G; Meng, C; Daamen, M; Baumann, N; Busch, B; Bartmann, P; Wolke, D; Boecker, H; Wohlschläger, A; Sorg, C; Jaekel, Julia

    2017-03-01

    Mathematic abilities in childhood are highly predictive for long-term neurocognitive outcomes. Preterm-born individuals have an increased risk for both persistent cognitive impairments and long-term changes in macroscopic brain organization. We hypothesized that the association of childhood mathematic abilities with both adulthood general cognitive abilities and associated fronto-parietal intrinsic networks is altered after preterm delivery. 72 preterm- and 71 term-born individuals underwent standardized mathematic and IQ testing at 8 years and resting-state fMRI and full-scale IQ testing at 26 years of age. Outcome measure for intrinsic networks was intrinsic functional connectivity (iFC). Controlling for IQ at age eight, mathematic abilities in childhood were significantly stronger positively associated with adults' IQ in preterm compared with term-born individuals. In preterm-born individuals, the association of children's mathematic abilities and adults' fronto-parietal iFC was altered. Likewise, fronto-parietal iFC was distinctively linked with preterm- and term-born adults' IQ. Results provide evidence that preterm birth alters the link of mathematic abilities in childhood and general cognitive abilities and fronto-parietal intrinsic networks in adulthood. Data suggest a distinct functional role of intrinsic fronto-parietal networks for preterm individuals with respect to mathematic abilities and that these networks together with associated children's mathematic abilities may represent potential neurocognitive targets for early intervention.

  16. Generalized anxiety disorder in racial and ethnic minorities: a case of nativity and contextual factors.

    PubMed

    Budhwani, Henna; Hearld, Kristine Ria; Chavez-Yenter, Daniel

    2015-04-01

    Minorities comprise more than one third of the U.S., and research on the correlates and causes of depression, anxiety, and other mental illnesses have yielded mixed results in minority groups necessitating an understanding of causes and correlates of health. Thus, the aim of this paper is to evaluate the relationship between minority status, contextual factors, and lifetime Generalized Anxiety Disorder. Logistic regression models were implemented, comparing immigrants to their American-born counterparts as well as to American-born Whites. Foreign-born Afro-Caribbeans exhibited lower rates of lifetime GAD. A lower percentage of foreign-born minorities met the criteria for GAD as compared to their American-born counterparts, and all racial and ethnic groups met the criteria for lifetime GAD at a lower rate as compared to American-born Whites. By using theory proactively and including contextual factors, this multi-faceted approach to health disparities research yielded findings which both supported historic beliefs but created opportunities for supplemental research looking at immigrants and GAD. Key findings were that health lifestyle choices and exposure to discrimination significantly affected the chance of having GAD. Nativity was protective; however, its effect was ameliorated by exposure to discrimination or engagement in alcohol abuse. Thus, this study offers practical insight into environmental factors for clinicians caring for racial and ethnic minorities diagnosed with GAD. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Investigation of High School Students' Online Science Information Searching Performance: The Role of Implicit and Explicit Strategies

    NASA Astrophysics Data System (ADS)

    Tsai, Meng-Jung; Hsu, Chung-Yuan; Tsai, Chin-Chung

    2012-04-01

    Due to a growing trend of exploring scientific knowledge on the Web, a number of studies have been conducted to highlight examination of students' online searching strategies. The investigation of online searching generally employs methods including a survey, interview, screen-capturing, or transactional logs. The present study firstly intended to utilize a survey, the Online Information Searching Strategies Inventory (OISSI), to examine users' searching strategies in terms of control, orientation, trial and error, problem solving, purposeful thinking, selecting main ideas, and evaluation, which is defined as implicit strategies. Second, this study conducted screen-capturing to investigate the students' searching behaviors regarding the number of keywords, the quantity and depth of Web page exploration, and time attributes, which is defined as explicit strategies. Ultimately, this study explored the role that these two types of strategies played in predicting the students' online science information searching outcomes. A total of 103 Grade 10 students were recruited from a high school in northern Taiwan. Through Pearson correlation and multiple regression analyses, the results showed that the students' explicit strategies, particularly the time attributes proposed in the present study, were more successful than their implicit strategies in predicting their outcomes of searching science information. The participants who spent more time on detailed reading (explicit strategies) and had better skills of evaluating Web information (implicit strategies) tended to have superior searching performance.

  18. The effect of combined avoidance and control training on implicit food evaluation and choice.

    PubMed

    Kakoschke, Naomi; Kemps, Eva; Tiggemann, Marika

    2017-06-01

    Continual exposure to food cues in the environment contributes to unhealthy eating behaviour. According to dual-process models, such behaviour is partly determined by automatic processing of unhealthy food cues (e.g., approach bias), which fails to be regulated by controlled processing (e.g., inhibitory control). The current study aimed to investigate the effect of combined avoidance and control training on implicit evaluation (liking), choice, and consumption of unhealthy snack food. Participants were 240 undergraduate women who were randomly allocated to one of four experimental conditions of a 2 (avoidance training: training versus control) x 2 (control training: training versus control) between-subjects design. The combined training group had a more negative implicit evaluation of unhealthy food than either of the two training conditions alone or the control condition. In addition, participants trained to avoid unhealthy food cues subsequently made fewer unhealthy snack food choices. No significant group differences were found for food intake. Participants were women generally of a healthy weight. Overweight or obese individuals may derive greater benefit from combined training. Results lend support to the theoretical predictions of dual-process models, as the combined training reduced implicit liking of unhealthy food. At a practical level, the findings have implications for the effectiveness of interventions targeting unhealthy eating behaviour. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. PIXIE3D: A Parallel, Implicit, eXtended MHD 3D Code

    NASA Astrophysics Data System (ADS)

    Chacon, Luis

    2006-10-01

    We report on the development of PIXIE3D, a 3D parallel, fully implicit Newton-Krylov extended MHD code in general curvilinear geometry. PIXIE3D employs a second-order, finite-volume-based spatial discretization that satisfies remarkable properties such as being conservative, solenoidal in the magnetic field to machine precision, non-dissipative, and linearly and nonlinearly stable in the absence of physical dissipation. PIXIE3D employs fully-implicit Newton-Krylov methods for the time advance. Currently, second-order implicit schemes such as Crank-Nicolson and BDF2 (2^nd order backward differentiation formula) are available. PIXIE3D is fully parallel (employs PETSc for parallelism), and exhibits excellent parallel scalability. A parallel, scalable, MG preconditioning strategy, based on physics-based preconditioning ideas, has been developed for resistive MHD, and is currently being extended to Hall MHD. In this poster, we will report on progress in the algorithmic formulation for extended MHD, as well as the the serial and parallel performance of PIXIE3D in a variety of problems and geometries. L. Chac'on, Comput. Phys. Comm., 163 (3), 143-171 (2004) L. Chac'on et al., J. Comput. Phys. 178 (1), 15- 36 (2002); J. Comput. Phys., 188 (2), 573-592 (2003) L. Chac'on, 32nd EPS Conf. Plasma Physics, Tarragona, Spain, 2005 L. Chac'on et al., 33rd EPS Conf. Plasma Physics, Rome, Italy, 2006

  20. Divorce in Families of Genetically Handicapped/Mentally Retarded Individuals.

    ERIC Educational Resources Information Center

    Roesel, Rosalyn; Lawlis, G. Frank

    1983-01-01

    Investigated divorce among parents (N=113) of mentally retarded/genetically handicapped children and found a divorce rate significantly lower than the general population. Young parents of handicapped first born males and older mothers of handicapped first borns were at a higher risk of divorce. (Author/JAC)

  1. Racial bias in pain perception and response: experimental examination of automatic and deliberate processes

    PubMed Central

    Mathur, Vani A.; Richeson, Jennifer A.; Paice, Judith A.; Muzyka, Michael; Chiao, Joan Y.

    2014-01-01

    Racial disparities in pain treatment pose a significant public health and scientific problem. Prior studies demonstrate clinicians and non-clinicians are less perceptive, and suggest less treatment for, the pain of African Americans, relative to European Americans. Here we investigate the effects of explicit/implicit patient race presentation, patient race, and perceiver race on pain perception and response. African American and European American participants rated pain perception, empathy, helping motivation, and treatment suggestion in response to vignettes about patients’ pain. Vignettes were accompanied by a rapid (implicit), or static (explicit) presentation of an African or European American patient’s face. Participants perceived and responded more to European American patients in the implicit prime condition, when the effect of patient race was below the level of conscious regulation. This effect was reversed when patient race was presented explicitly. Additionally, female participants perceived and responded more to the pain of all patients, relative to male participants, and in the implicit prime condition, African American participants were more perceptive and responsive than European Americans to the pain of all patients. Taken together, these results suggest that known disparities in pain treatment may be largely due to automatic (below the level of conscious regulation), rather than deliberate (subject to conscious regulation) biases. These biases were not associated with traditional implicit measures of racial attitudes, suggesting that biases in pain perception and response may be independent of general prejudice. Perspective Results suggest racial biases in pain perception and treatment are at least partially due to automatic processes. When the relevance of patient race is made explicit, however, biases are attenuated and even reversed. We also find preliminary evidence that African Americans may be more sensitive to the pain of others than European Americans. PMID:24462976

  2. A new heterogeneous asynchronous explicit-implicit time integrator for nonsmooth dynamics

    NASA Astrophysics Data System (ADS)

    Fekak, Fatima-Ezzahra; Brun, Michael; Gravouil, Anthony; Depale, Bruno

    2017-07-01

    In computational structural dynamics, particularly in the presence of nonsmooth behavior, the choice of the time-step and the time integrator has a critical impact on the feasibility of the simulation. Furthermore, in some cases, as in the case of a bridge crane under seismic loading, multiple time-scales coexist in the same problem. In that case, the use of multi-time scale methods is suitable. Here, we propose a new explicit-implicit heterogeneous asynchronous time integrator (HATI) for nonsmooth transient dynamics with frictionless unilateral contacts and impacts. Furthermore, we present a new explicit time integrator for contact/impact problems where the contact constraints are enforced using a Lagrange multiplier method. In other words, the aim of this paper consists in using an explicit time integrator with a fine time scale in the contact area for reproducing high frequency phenomena, while an implicit time integrator is adopted in the other parts in order to reproduce much low frequency phenomena and to optimize the CPU time. In a first step, the explicit time integrator is tested on a one-dimensional example and compared to Moreau-Jean's event-capturing schemes. The explicit algorithm is found to be very accurate and the scheme has generally a higher order of convergence than Moreau-Jean's schemes and provides also an excellent energy behavior. Then, the two time scales explicit-implicit HATI is applied to the numerical example of a bridge crane under seismic loading. The results are validated in comparison to a fine scale full explicit computation. The energy dissipated in the implicit-explicit interface is well controlled and the computational time is lower than a full-explicit simulation.

  3. Neural Measures Reveal Implicit Learning during Language Processing.

    PubMed

    Batterink, Laura J; Cheng, Larry Y; Paller, Ken A

    2016-10-01

    Language input is highly variable; phonological, lexical, and syntactic features vary systematically across different speakers, geographic regions, and social contexts. Previous evidence shows that language users are sensitive to these contextual changes and that they can rapidly adapt to local regularities. For example, listeners quickly adjust to accented speech, facilitating comprehension. It has been proposed that this type of adaptation is a form of implicit learning. This study examined a similar type of adaptation, syntactic adaptation, to address two issues: (1) whether language comprehenders are sensitive to a subtle probabilistic contingency between an extraneous feature (font color) and syntactic structure and (2) whether this sensitivity should be attributed to implicit learning. Participants read a large set of sentences, 40% of which were garden-path sentences containing temporary syntactic ambiguities. Critically, but unbeknownst to participants, font color probabilistically predicted the presence of a garden-path structure, with 75% of garden-path sentences (and 25% of normative sentences) appearing in a given font color. ERPs were recorded during sentence processing. Almost all participants indicated no conscious awareness of the relationship between font color and sentence structure. Nonetheless, after sufficient time to learn this relationship, ERPs time-locked to the point of syntactic ambiguity resolution in garden-path sentences differed significantly as a function of font color. End-of-sentence grammaticality judgments were also influenced by font color, suggesting that a match between font color and sentence structure increased processing fluency. Overall, these findings indicate that participants can implicitly detect subtle co-occurrences between physical features of sentences and abstract, syntactic properties, supporting the notion that implicit learning mechanisms are generally operative during online language processing.

  4. Alexithymia Components Are Differentially Related to Explicit Negative Affect But Not Associated with Explicit Positive Affect or Implicit Affectivity.

    PubMed

    Suslow, Thomas; Donges, Uta-Susan

    2017-01-01

    Alexithymia represents a multifaceted personality construct defined by difficulties in recognizing and verbalizing emotions and externally oriented thinking. According to clinical observations, experience of negative affects is exacerbated and experience of positive affects is decreased in alexithymia. Findings from research based on self-report indicate that all alexithymia facets are negatively associated with the experience of positive affects, whereas difficulties identifying and describing feelings are related to heightened negative affect. Implicit affectivity, which can be measured using indirect assessment methods, relates to processes of the impulsive system. The aim of the present study was to examine, for the first time, the relations between alexithymia components and implicit and explicit positive and negative affectivity in healthy adults. The 20-item Toronto Alexithymia Scale, the Implicit Positive and Negative Affect Test and the Positive and Negative Affect Schedule (PANAS) were administered to two hundred and forty-one healthy individuals along with measures of depression and trait anxiety. Difficulties identifying feelings were correlated with explicit negative trait affect, depressive mood and trait anxiety. Difficulties describing feelings showed smaller but also significant correlations with depressive mood and trait anxiety but were not correlated with explicit state or trait affect as assessed by the PANAS. Externally oriented thinking was not significantly correlated with any of the implicit and explicit affect measures. According to our findings, an externally oriented, concrete way of thinking appears to be generally unrelated to dispositions to develop positive or negative affects. Difficulties identifying feelings seem to be associated with increased conscious negative affects but not with a heightened disposition to develop negative affects at an automatic response level.

  5. Immigrants from Mexico experience serious behavioral and psychiatric problems at far lower rates than US-born Americans.

    PubMed

    Salas-Wright, Christopher P; Vaughn, Michael G; Goings, Trenette Clark

    2017-10-01

    To examine the prevalence of self-reported criminal and violent behavior, substance use disorders, and mental disorders among Mexican immigrants vis-à-vis the US born. Study findings are based on national data collected between 2012 and 2013. Binomial logistic regression was employed to examine the relationship between immigrant status and behavioral/psychiatric outcomes. Mexican immigrants report substantially lower levels of criminal and violent behaviors, substance use disorders, and mental disorders compared to US-born individuals. While some immigrants from Mexico have serious behavioral and psychiatric problems, Mexican immigrants in general experience such problems at far lower rates than US-born individuals.

  6. Kindergartners’ Fluent Processing of Symbolic Numerical Magnitude is Predicted by Their Cardinal Knowledge and Implicit Understanding of Arithmetic Two Years Earlier

    PubMed Central

    Moore, Alex M.; vanMarle, Kristy; Geary, David C.

    2016-01-01

    Fluency in first graders’ processing of the magnitudes associated with Arabic numerals, collections of objects, and mixtures of objects and numerals predicts current and future mathematics achievement. The quantitative competencies that support the development of fluent processing of magnitude are not fully understood, however. At the beginning and end of preschool (M = 3 years, 9 months at first assessment; range 3 years, 3 months to 4years, 3 months), 112 (51 boys) children completed tasks measuring numeral recognition and comparison, acuity of the approximate number system, and knowledge of counting principles, cardinality, and implicit arithmetic, and completed a magnitude processing task (number sets test) in kindergarten. Use of Bayesian and linear regression techniques revealed that two measures of preschoolers’ cardinal knowledge and their competence at implicit arithmetic predicted later fluency of magnitude processing, controlling domain general factors, preliteracy skills, and parental education. The results help to narrow the search for the early foundation of children’s emerging competence with symbolic mathematics and provide direction for early interventions. PMID:27236038

  7. Kindergartners' fluent processing of symbolic numerical magnitude is predicted by their cardinal knowledge and implicit understanding of arithmetic 2years earlier.

    PubMed

    Moore, Alex M; vanMarle, Kristy; Geary, David C

    2016-10-01

    Fluency in first graders' processing of the magnitudes associated with Arabic numerals, collections of objects, and mixtures of objects and numerals predicts current and future mathematics achievement. The quantitative competencies that support the development of fluent processing of magnitude, however, are not fully understood. At the beginning and end of preschool (M=3years 9months at first assessment, range=3years 3months to 4years 3months), 112 children (51 boys) completed tasks measuring numeral recognition and comparison, acuity of the approximate number system, and knowledge of counting principles, cardinality, and implicit arithmetic and also completed a magnitude processing task (number sets test) in kindergarten. Use of Bayesian and linear regression techniques revealed that two measures of preschoolers' cardinal knowledge and their competence at implicit arithmetic predicted later fluency of magnitude processing, controlling domain-general factors, preliteracy skills, and parental education. The results help to narrow the search for the early foundation of children's emerging competence with symbolic mathematics and provide direction for early interventions. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. An analytical particle mover for the charge- and energy-conserving, nonlinearly implicit, electrostatic particle-in-cell algorithm

    NASA Astrophysics Data System (ADS)

    Chen, G.; Chacón, L.

    2013-08-01

    We propose a 1D analytical particle mover for the recent charge- and energy-conserving electrostatic particle-in-cell (PIC) algorithm in Ref. [G. Chen, L. Chacón, D.C. Barnes, An energy- and charge-conserving, implicit, electrostatic particle-in-cell algorithm, Journal of Computational Physics 230 (2011) 7018-7036]. The approach computes particle orbits exactly for a given piece-wise linear electric field. The resulting PIC algorithm maintains the exact charge and energy conservation properties of the original algorithm, but with improved performance (both in efficiency and robustness against the number of particles and timestep). We demonstrate the advantageous properties of the scheme with a challenging multiscale numerical test case, the ion acoustic wave. Using the analytical mover as a reference, we demonstrate that the choice of error estimator in the Crank-Nicolson mover has significant impact on the overall performance of the implicit PIC algorithm. The generalization of the approach to the multi-dimensional case is outlined, based on a novel and simple charge conserving interpolation scheme.

  9. Two-level schemes for the advection equation

    NASA Astrophysics Data System (ADS)

    Vabishchevich, Petr N.

    2018-06-01

    The advection equation is the basis for mathematical models of continuum mechanics. In the approximate solution of nonstationary problems it is necessary to inherit main properties of the conservatism and monotonicity of the solution. In this paper, the advection equation is written in the symmetric form, where the advection operator is the half-sum of advection operators in conservative (divergent) and non-conservative (characteristic) forms. The advection operator is skew-symmetric. Standard finite element approximations in space are used. The standard explicit two-level scheme for the advection equation is absolutely unstable. New conditionally stable regularized schemes are constructed, on the basis of the general theory of stability (well-posedness) of operator-difference schemes, the stability conditions of the explicit Lax-Wendroff scheme are established. Unconditionally stable and conservative schemes are implicit schemes of the second (Crank-Nicolson scheme) and fourth order. The conditionally stable implicit Lax-Wendroff scheme is constructed. The accuracy of the investigated explicit and implicit two-level schemes for an approximate solution of the advection equation is illustrated by the numerical results of a model two-dimensional problem.

  10. Stress-related biomarkers of dream recall and implicit memory under anaesthesia.

    PubMed

    Aceto, P; Lai, C; Perilli, V; Dello Russo, C; Federico, B; Navarra, P; Proietti, R; Sollazzi, L

    2013-11-01

    The aim of this study was to investigate whether auditory presentation of a story during general anaesthesia might influence stress hormone changes and thus affecting dream recall and/or implicit memory. One hundred and ten patients were randomly assigned either to hear a recording of a story through headphones or to have routine care with no auditory recording while undergoing laparoscopic cholecystectomy. Anaesthesia was standardised. Blood samples for cortisol and prolactin assays were collected 20 min before anaesthesia and 5 min after pneumoperitoneum. Dream recall and explicit/implicit memory were investigated upon awakening from anaesthesia and approximately 24 h after the end of the operation. Auditory presentation was associated with lower intra-operative serum prolactin concentration compared with control (p = 0.0006). Twenty-seven patients with recall of dreaming showed higher intra-operative prolactin (p = 0.004) and lower cortisol (p = 0.03) concentrations compared with those without dream recall. The knowledge of this interaction might be useful in the quest to ensure postoperative amnesia. © 2013 The Association of Anaesthetists of Great Britain and Ireland.

  11. Implicit preferences: the role(s) of familiarity in the structural mere exposure effect.

    PubMed

    Zizak, Diane M; Reber, Arthur S

    2004-06-01

    In four experiments using an artificial grammar (AG) learning procedure, the authors examined the links between the "classic" mere exposure effect [heightened affect for previously encountered stimulus items (Bornstein, 1989; Zajonc, 1968)] and the "structural" mere exposure effect [greater hedonic appreciation for novel stimuli that conform to an implicitly acquired underlying rule system (Gordon & Holyoak, 1983)]. After learning, participants: (a) classified stimuli according to whether they conformed to the principles of the grammar and, (b) rated them in terms of how much they liked them. In some experiments unusual and unfamiliar symbols were used to instantiate the AG, in others highly familiar characters were used. In all cases participants showed standard AG learning. However, whether the two exposure effects emerged was dependent on symbol familiarity. Symbols with high a priori familiarity produced a structural mere exposure effect. Moderately familiar symbols produced only the classic, but not the structural, mere exposure effect. Highly unfamiliar symbols produced neither exposure effect. Results are discussed in the context of implicit learning theory and implications for a general theory of aesthetics are presented.

  12. Disentangling perceptual from motor implicit sequence learning with a serial color-matching task.

    PubMed

    Gheysen, Freja; Gevers, Wim; De Schutter, Erik; Van Waelvelde, Hilde; Fias, Wim

    2009-08-01

    This paper contributes to the domain of implicit sequence learning by presenting a new version of the serial reaction time (SRT) task that allows unambiguously separating perceptual from motor learning. Participants matched the colors of three small squares with the color of a subsequently presented large target square. An identical sequential structure was tied to the colors of the target square (perceptual version, Experiment 1) or to the manual responses (motor version, Experiment 2). Short blocks of sequenced and randomized trials alternated and hence provided a continuous monitoring of the learning process. Reaction time measurements demonstrated clear evidence of independently learning perceptual and motor serial information, though revealed different time courses between both learning processes. No explicit awareness of the serial structure was needed for either of the two types of learning to occur. The paradigm introduced in this paper evidenced that perceptual learning can occur with SRT measurements and opens important perspectives for future imaging studies to answer the ongoing question, which brain areas are involved in the implicit learning of modality specific (motor vs. perceptual) or general serial order.

  13. Virtual lesions of the inferior parietal cortex induce fast changes of implicit religiousness/spirituality.

    PubMed

    Crescentini, Cristiano; Aglioti, Salvatore M; Fabbro, Franco; Urgesi, Cosimo

    2014-05-01

    Religiousness and spirituality (RS) are two ubiquitous aspects of human experience typically considered impervious to scientific investigation. Nevertheless, associations between RS and frontoparietal neural activity have been recently reported. However, much less is known about whether such activity is causally involved in modulating RS or just epiphenomenal to them. Here we combined two-pulse (10 Hz) Transcranial Magnetic Stimulation (TMS) with a novel, ad-hoc developed RS-related, Implicit Association Test (IAT) to investigate whether implicit RS representations, although supposedly rather stable, can be rapidly modified by a virtual lesion of inferior parietal lobe (IPL) and dorsolateral prefrontal cortex (DLPFC). A self-esteem (SE) IAT, focused on self-concepts nonrelated to RS representations, was developed as control. A specific increase of RS followed inhibition of IPL demonstrating its causative role in inducing fast plastic changes of religiousness/spirituality. In contrast, DLPFC inhibition had more widespread effects probably reflecting a general role in the acquisition or maintenance of task-rules or in controlling the expression of self-related representations not specific to RS. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Electrophysiological correlates of implicit valenced self-processing in high vs. low self-esteem individuals.

    PubMed

    Grundy, John G; Benarroch, Miriam F F; Lebarr, A Nicole; Shedden, Judith M

    2015-01-01

    We provide the first high-temporal resolution account of the self-esteem implicit association test (IAT; Greenwald & Farnham, 2000) to highlight important similarities and differences between the cognitive processes corresponding to implicit valenced self-processing in high vs. low self-esteem individuals. We divided individuals into high and low self-esteem groups based on the Rosenberg self-esteem scale (Rosenberg, 1965) and administered the self-esteem IAT while recording electroencephalographic data. We show that the P2 captured group (high vs. low self-esteem) differences, the N250 and the late parietal positivity (LPP) captured differences corresponding to category pairing (self/positive vs. self/negative pairing), and the N1, P2, and P300-400 components captured interactions between self-esteem groups and whether the self was paired with positive or negative categories in the IAT. Overall, both high and low self-esteem groups were sensitive to the distinction between positive and negative information in relation to the self (me/negative generally displayed larger event-related potential amplitudes than me/positive), but for high self-esteem individuals, this difference was generally larger, earlier, and most pronounced over left-hemisphere electrodes. These electrophysiological differences may reflect differences in attentional resources devoted to teasing apart these two oppositely valenced associations. High self-esteem individuals appear to devote more automatic (early) attentional resources to strengthen the distinction between positively or negatively valenced information in relation to the self.

  15. Making Implicit Multivariable Calculus Representations Explicit: A Clinical Study

    ERIC Educational Resources Information Center

    McGee, Daniel; Moore-Russo, Deborah; Martinez-Planell, Rafael

    2015-01-01

    Reviewing numerous textbooks, we found that in both differential and integral calculus textbooks the authors commonly assume that: (i) students can generalize associations between representations in two dimensions to associations between representations of the same mathematical concept in three dimensions on their own; and (ii) explicit…

  16. State Financing of Higher Education: A New Look at an Old Problem.

    ERIC Educational Resources Information Center

    Fischer, Frederick J.

    1990-01-01

    There is an implicit general plan currently uniting federal and state financing policies, however, it is inefficient, inequitable, and ineffective, involving obsolete state financing policies and mistaken federal responses. Implementation of another plan available would require federal intervention in state financing policies. (MLW)

  17. Hunter's Syndrome: Description and Educational Considerations.

    ERIC Educational Resources Information Center

    Naggs, Teresa

    This paper describes characteristics of and educational implications for children with Hunter's syndrome, a rare, genetic lysomal storage disorder resulting from an absence of the enzyme iduronate-2-sulphatase. Boys born with this sex-linked disease are born with little or no clinical manifestations, but generally are diagnosed by the age of three…

  18. Prediction of potency of protease inhibitors using free energy simulations with polarizable quantum mechanics-based ligand charges and a hybrid water model.

    PubMed

    Das, Debananda; Koh, Yasuhiro; Tojo, Yasushi; Ghosh, Arun K; Mitsuya, Hiroaki

    2009-12-01

    Reliable and robust prediction of the binding affinity for drug molecules continues to be a daunting challenge. We simulated the binding interactions and free energy of binding of nine protease inhibitors (PIs) with wild-type and various mutant proteases by performing GBSA simulations in which each PI's partial charge was determined by quantum mechanics (QM) and the partial charge accounts for the polarization induced by the protease environment. We employed a hybrid solvation model that retains selected explicit water molecules in the protein with surface-generalized Born (SGB) implicit solvent. We examined the correlation of the free energy with the antiviral potency of PIs with regard to amino acid substitutions in protease. The GBSA free energy thus simulated showed strong correlations (r > 0.75) with antiviral IC(50) values of PIs when amino acid substitutions were present in the protease active site. We also simulated the binding free energy of PIs with P2-bis-tetrahydrofuranylurethane (bis-THF) or related cores, utilizing a bis-THF-containing protease crystal structure as a template. The free energy showed a strong correlation (r = 0.93) with experimentally determined anti-HIV-1 potency. The present data suggest that the presence of selected explicit water in protein and protein polarization-induced quantum charges for the inhibitor, compared to lack of explicit water and a static force-field-based charge model, can serve as an improved lead optimization tool and warrants further exploration.

  19. A charge- and energy-conserving implicit, electrostatic particle-in-cell algorithm on mapped computational meshes

    NASA Astrophysics Data System (ADS)

    Chacón, L.; Chen, G.; Barnes, D. C.

    2013-01-01

    We describe the extension of the recent charge- and energy-conserving one-dimensional electrostatic particle-in-cell algorithm in Ref. [G. Chen, L. Chacón, D.C. Barnes, An energy- and charge-conserving, implicit electrostatic particle-in-cell algorithm, Journal of Computational Physics 230 (2011) 7018-7036] to mapped (body-fitted) computational meshes. The approach maintains exact charge and energy conservation properties. Key to the algorithm is a hybrid push, where particle positions are updated in logical space, while velocities are updated in physical space. The effectiveness of the approach is demonstrated with a challenging numerical test case, the ion acoustic shock wave. The generalization of the approach to multiple dimensions is outlined.

  20. Implicit solvers for unstructured meshes

    NASA Technical Reports Server (NTRS)

    Venkatakrishnan, V.; Mavriplis, Dimitri J.

    1991-01-01

    Implicit methods were developed and tested for unstructured mesh computations. The approximate system which arises from the Newton linearization of the nonlinear evolution operator is solved by using the preconditioned GMRES (Generalized Minimum Residual) technique. Three different preconditioners were studied, namely, the incomplete LU factorization (ILU), block diagonal factorization, and the symmetric successive over relaxation (SSOR). The preconditioners were optimized to have good vectorization properties. SSOR and ILU were also studied as iterative schemes. The various methods are compared over a wide range of problems. Ordering of the unknowns, which affects the convergence of these sparse matrix iterative methods, is also studied. Results are presented for inviscid and turbulent viscous calculations on single and multielement airfoil configurations using globally and adaptively generated meshes.

  1. Multigrid Method for Modeling Multi-Dimensional Combustion with Detailed Chemistry

    NASA Technical Reports Server (NTRS)

    Zheng, Xiaoqing; Liu, Chaoqun; Liao, Changming; Liu, Zhining; McCormick, Steve

    1996-01-01

    A highly accurate and efficient numerical method is developed for modeling 3-D reacting flows with detailed chemistry. A contravariant velocity-based governing system is developed for general curvilinear coordinates to maintain simplicity of the continuity equation and compactness of the discretization stencil. A fully-implicit backward Euler technique and a third-order monotone upwind-biased scheme on a staggered grid are used for the respective temporal and spatial terms. An efficient semi-coarsening multigrid method based on line-distributive relaxation is used as the flow solver. The species equations are solved in a fully coupled way and the chemical reaction source terms are treated implicitly. Example results are shown for a 3-D gas turbine combustor with strong swirling inflows.

  2. An advanced probabilistic structural analysis method for implicit performance functions

    NASA Technical Reports Server (NTRS)

    Wu, Y.-T.; Millwater, H. R.; Cruse, T. A.

    1989-01-01

    In probabilistic structural analysis, the performance or response functions usually are implicitly defined and must be solved by numerical analysis methods such as finite element methods. In such cases, the most commonly used probabilistic analysis tool is the mean-based, second-moment method which provides only the first two statistical moments. This paper presents a generalized advanced mean value (AMV) method which is capable of establishing the distributions to provide additional information for reliability design. The method requires slightly more computations than the second-moment method but is highly efficient relative to the other alternative methods. In particular, the examples show that the AMV method can be used to solve problems involving non-monotonic functions that result in truncated distributions.

  3. When 95% Accurate Isn't: Exploring Bayes's Theorem

    ERIC Educational Resources Information Center

    CadwalladerOlsker, Todd D.

    2011-01-01

    Bayes's theorem is notorious for being a difficult topic to learn and to teach. Problems involving Bayes's theorem (either implicitly or explicitly) generally involve calculations based on two or more given probabilities and their complements. Further, a correct solution depends on students' ability to interpret the problem correctly. Most people…

  4. 78 FR 69543 - Record Requirements in the Mechanical Power Presses Standard

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-20

    ... perform maintenance and repair necessary for the safe operation of the entire press is implicit in the... of general industry, but OSHA believes that adding an explicit requirement to perform necessary... required by existing paragraph (e)(1)(ii) serve the following functions: (i) Remind employers to inspect...

  5. The Effect of Mortality Salience on Implicit Bias

    ERIC Educational Resources Information Center

    Bradley, Kristopher I.; Kennison, Shelia M.; Burke, Amanda L.; Chaney, John M.

    2012-01-01

    Previous research in terror management theory has shown that when individuals are reminded of their mortality, negative evaluations of out-group members increase. This previous research has used a variety of methods to investigate the change in attitudes toward out-group members. These methods generally permit participants time to consciously…

  6. Realistic Fasting Does Not Affect Stable Isotope Levels of a Metabolically Efficient Salamander

    EPA Science Inventory

    Stable isotopes are commonly used to examine various aspects of animal ecology. The use of stable isotopes generally proceeds under the implicit assumption that resource use is the only factor driving variation in stable isotope levels; however, a wealth of studies demonstrate a...

  7. The Etiology of Giftedness

    ERIC Educational Resources Information Center

    Thompson, Lee Anne; Oehlert, Jeremy

    2010-01-01

    Many theories of giftedness either explicitly or implicitly acknowledge the role of genetic influences; yet, empirical work has not been able to establish the impact that genes have specifically on gifted behavior. In contrast, a great deal of research has been targeted at understanding the etiology of individual differences in general and…

  8. New solution decomposition and minimization schemes for Poisson-Boltzmann equation in calculation of biomolecular electrostatics

    NASA Astrophysics Data System (ADS)

    Xie, Dexuan

    2014-10-01

    The Poisson-Boltzmann equation (PBE) is one widely-used implicit solvent continuum model in the calculation of electrostatic potential energy for biomolecules in ionic solvent, but its numerical solution remains a challenge due to its strong singularity and nonlinearity caused by its singular distribution source terms and exponential nonlinear terms. To effectively deal with such a challenge, in this paper, new solution decomposition and minimization schemes are proposed, together with a new PBE analysis on solution existence and uniqueness. Moreover, a PBE finite element program package is developed in Python based on the FEniCS program library and GAMer, a molecular surface and volumetric mesh generation program package. Numerical tests on proteins and a nonlinear Born ball model with an analytical solution validate the new solution decomposition and minimization schemes, and demonstrate the effectiveness and efficiency of the new PBE finite element program package.

  9. Doctors and Vampires in Sub-Saharan Africa: Ethical Challenges in Clinical Trial Research

    PubMed Central

    Peeters Grietens, Koen; Ribera, Joan Muela; Erhart, Annette; Hoibak, Sarah; Ravinetto, Raffaella M.; Gryseels, Charlotte; Dierickx, Susan; O'Neill, Sarah; Muela, Susanna Hausmann; D'Alessandro, Umberto

    2014-01-01

    Collecting blood samples from individuals recruited into clinical research projects in sub-Saharan Africa can be challenging. Strikingly, one of the reasons for participant reticence is the occurrence of local rumors surrounding “blood stealing” or “blood selling.” Such fears can potentially have dire effects on the success of research projects—for example, high dropout rates that would invalidate the trial's results—and have ethical implications related to cultural sensitivity and informed consent. Though commonly considered as a manifestation of the local population's ignorance, these rumors represent a social diagnosis and a logical attempt to make sense of sickness and health. Born from historical antecedents, they reflect implicit contemporary structural inequalities and the social distance between communities and public health institutions. We aim at illustrating the underlying logic governing patients' fear and argue that the management of these beliefs should become an intrinsic component of clinical research. PMID:24821846

  10. Psychological reality of cross-media artistic styles.

    PubMed

    Hasenfus, N; Martindale, C; Birnbaum, D

    1983-12-01

    The sensitivity of artistically naive people to cross-media styles (baroque, neoclassic, and romantic) and to period styles (works composed by artists born during the same epoch) in four media (painting, poetry, music, and architecture) was assessed. In two studies, adult subjects tended spontaneously to sort stimuli according to both cross-media styles and period styles. In a third study, nursery school children were shown to be able to sort pictures of paintings and architectural facades on the basis of cross-media styles. Other experiments using rating scales again demonstrated that artistically naive adults are sensitive to both cross-media styles and period styles even when they are not implicitly urged to disregard medium. These and other studies using rating scales suggested that the bases for discrimination of both cross-media styles and period styles are the dimensions of realistic versus unrealistic and of overall arousal potential.

  11. Immigrant residential segregation in U.S. metropolitan areas, 1990-2000.

    PubMed

    Iceland, John; Scopilliti, Melissa

    2008-02-01

    This paper examines the extent of spatial assimilation among immigrants of different racial and ethnic origins. We use restricted data from the 1990 and 2000 censuses to calculate the levels of dissimilarity by race and Hispanic origin, nativity, and year of entry, and then run multivariate models to examine these relationships. The findings provide broad support for spatial assimilation theory. Foreign-born Hispanics, Asians, and blacks are more segregated from native-born non-Hispanic whites than are the U.S.-born of these groups. The patterns for Hispanics and Asians can be explained by the average characteristics of the foreign-born that are generally associated with higher levels of segregation, such as lower levels of income, English language ability, and home ownership. We also find that immigrants who have been in the United States for longer periods are generally less segregated than new arrivals, and once again, much of this difference can be attributed to the characteristics of immigrants. However, patterns also vary across groups. Levels of segregation are much higher for black immigrants than for Asian, Hispanic, and white immigrants. In addition, because black immigrants are, on average, of higher socioeconomic status than native-born blacks, such characteristics do not help explain their very high levels of segregation.

  12. Obesity Among U.S.- and Foreign-Born Blacks by Region of Birth.

    PubMed

    Mehta, Neil K; Elo, Irma T; Ford, Nicole D; Siegel, Karen R

    2015-08-01

    Large, recent migration streams from the non-Hispanic Caribbean islands and Africa have increased the share of U.S. blacks born outside of the U.S. Little is known about health patterns in these foreign-born populations. The purpose of this study is to compare obesity levels among self-identified U.S. blacks across birth regions and examine potential explanations for subgroup differences. Data were from the 2000-2013 National Health Interview Surveys. Three birthplace subgroups were examined: individuals born in the U.S., Caribbean/South America, and Africa, aged 25-59 years. Data were analyzed in 2013-2014. Compared to U.S.-born participants, foreign-born participants had significantly lower obesity (BMI ≥30) odds. The AORs were 0.51 (Caribbean/South American-born, 95% CI=0.44, 0.58) and 0.41 (African-born, 95% CI=0.34, 0.50) with reference to U.S.-born individuals. Education, income, and cigarette smoking did not explain the favorable weight pattern of the foreign born. Among the foreign born, those residing in the U.S. for ≥15 years had 51% (95% CI=10%, 108%) higher obesity odds compared with those residing for <5 years. No statistically significant differences in obesity odds between those born in the Caribbean/South America and Africa were detected. Foreign-born blacks generally had lower obesity levels compared to their U.S.-born counterparts, which was not explained by SES or smoking behaviors. Despite this advantage, obesity prevalence among foreign-born black women was around 30%, suggesting that obesity poses a significant health risk this population. Copyright © 2015 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

  13. Strong Convergence for a Finite Family of Generalized Asymptotically Nonexpansive Mappings

    NASA Astrophysics Data System (ADS)

    Ma, Zhi-Hong; Chen, Ru-Dond

    The purpose of this paper is to show the convergence theorems for generalized asymptotically nonexpansive mappings and asymptotically nonexpansive mappings in Banach spaces by using a new iteration which is a natural generalization of the implicit iteration. In the meantime, we give the necessary and sufficient conditions of the strong convergence to approximate a common fixed point and modify some flaw in the results of Thakur [11]. As one will see, the results presented in this paper are an extension of the corresponding results [8,11].

  14. Measuring implicit attitudes: A positive framing bias flaw in the Implicit Relational Assessment Procedure (IRAP).

    PubMed

    O'Shea, Brian; Watson, Derrick G; Brown, Gordon D A

    2016-02-01

    How can implicit attitudes best be measured? The Implicit Relational Assessment Procedure (IRAP), unlike the Implicit Association Test (IAT), claims to measure absolute, not just relative, implicit attitudes. In the IRAP, participants make congruent (Fat Person-Active: false; Fat Person-Unhealthy: true) or incongruent (Fat Person-Active: true; Fat Person-Unhealthy: false) responses in different blocks of trials. IRAP experiments have reported positive or neutral implicit attitudes (e.g., neutral attitudes toward fat people) in cases in which negative attitudes are normally found on explicit or other implicit measures. It was hypothesized that these results might reflect a positive framing bias (PFB) that occurs when participants complete the IRAP. Implicit attitudes toward categories with varying prior associations (nonwords, social systems, flowers and insects, thin and fat people) were measured. Three conditions (standard, positive framing, and negative framing) were used to measure whether framing influenced estimates of implicit attitudes. It was found that IRAP scores were influenced by how the task was framed to the participants, that the framing effect was modulated by the strength of prior stimulus associations, and that a default PFB led to an overestimation of positive implicit attitudes when measured by the IRAP. Overall, the findings question the validity of the IRAP as a tool for the measurement of absolute implicit attitudes. A new tool (Simple Implicit Procedure:SIP) for measuring absolute, not just relative, implicit attitudes is proposed. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  15. 7 CFR 65.260 - United States country of origin.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 3 2012-01-01 2012-01-01 false United States country of origin. 65.260 Section 65.260..., PEANUTS, AND GINSENG General Provisions Definitions § 65.260 United States country of origin. United... exclusively born, raised, and slaughtered in the United States; (2) From animals born and raised in Alaska or...

  16. General framework for comparative quantitative studies on transmission of tick-borne diseases using Lyme borreliosis in Europe as an example.

    PubMed

    Randolph, S E; Craine, N G

    1995-11-01

    Models of tick-borne diseases must take account of the particular biological features of ticks that contrast with those of insect vectors. A general framework is proposed that identifies the parameters of the transmission dynamics of tick-borne diseases to allow a quantitative assessment of the relative contributions of different host species and alternative transmission routes to the basic reproductive number, Ro, of such diseases. Taking the particular case of the transmission of the Lyme borreliosis spirochaete, Borrelia burgdorferi, by Ixodes ticks in Europe, and using the best, albeit still inadequate, estimates of the parameter values and a set of empirical data from Thetford Forest, England, we show that squirrels and the transovarial transmission route make quantitatively very significant contributions to Ro. This approach highlights the urgent need for more robust estimates of certain crucial parameter values, particularly the coefficients of transmission between ticks and vertebrates, before we can progress to full models that incorporate seasonality and heterogeneity among host populations for the natural dynamics of transmission of borreliosis and other tick-borne diseases.

  17. Gifted Students' Implicit Beliefs about Intelligence and Giftedness

    ERIC Educational Resources Information Center

    Makel, Matthew C.; Snyder, Kate E.; Thomas, Chandler; Malone, Patrick S.; Putallaz, Martha

    2015-01-01

    Growing attention is being paid to individuals' implicit beliefs about the nature of intelligence. However, implicit beliefs about giftedness are currently underexamined. In the current study, we examined academically gifted adolescents' implicit beliefs about both intelligence and giftedness. Overall, participants' implicit beliefs about…

  18. Air-borne and tissue-borne sensitivities of bioacoustic sensors used on the skin surface.

    PubMed

    Zañartu, Matías; Ho, Julio C; Kraman, Steve S; Pasterkamp, Hans; Huber, Jessica E; Wodicka, George R

    2009-02-01

    Measurements of body sounds on the skin surface have been widely used in the medical field and continue to be a topic of current research, ranging from the diagnosis of respiratory and cardiovascular diseases to the monitoring of voice dosimetry. These measurements are typically made using light-weight accelerometers and/or air-coupled microphones attached to the skin. Although normally neglected, air-borne sounds generated by the subject or other sources of background noise can easily corrupt such recordings, which is particularly critical in the recording of voiced sounds on the skin surface. In this study, the sensitivity of commonly used bioacoustic sensors to air-borne sounds was evaluated and compared with their sensitivity to tissue-borne body sounds. To delineate the sensitivity to each pathway, the sensors were first tested in vitro and then on human subjects. The results indicated that, in general, the air-borne sensitivity is sufficiently high to significantly corrupt body sound signals. In addition, the air-borne and tissue-borne sensitivities can be used to discriminate between these components. Although the study is focused on the evaluation of voiced sounds on the skin surface, an extension of the proposed methods to other bioacoustic applications is discussed.

  19. Implicit and explicit self-esteem in currently depressed individuals with and without suicidal ideation.

    PubMed

    Franck, Erik; De Raedt, Rudi; Dereu, Mieke; Van den Abbeele, Dirk

    2007-03-01

    In the present study, we have further explored implicit self-esteem in currently depressed individuals. Since suicidal ideation is associated with lower self-esteem in depressed individuals, we measured both implicit and explicit self-esteem in a population of currently depressed (CD) individuals, with and without suicidal ideation (SI), and in a group of non-depressed controls (ND). The results indicate that only CD individuals with SI show a discrepancy between their implicit and explicit self-esteem: that is, they exhibit high implicit and low explicit self-esteem. CD individuals without SI exhibit both low implicit and low explicit self-esteem; and ND controls exhibit both normal implicit and normal explicit self-esteem. These results provide new insights in the study of implicit self-esteem and the combination of implicit and explicit self-esteem in depression.

  20. An energy- and charge-conserving, nonlinearly implicit, electromagnetic 1D-3V Vlasov-Darwin particle-in-cell algorithm

    NASA Astrophysics Data System (ADS)

    Chen, G.; Chacón, L.

    2014-10-01

    A recent proof-of-principle study proposes a nonlinear electrostatic implicit particle-in-cell (PIC) algorithm in one dimension (Chen et al., 2011). The algorithm employs a kinetically enslaved Jacobian-free Newton-Krylov (JFNK) method, and conserves energy and charge to numerical round-off. In this study, we generalize the method to electromagnetic simulations in 1D using the Darwin approximation to Maxwell's equations, which avoids radiative noise issues by ordering out the light wave. An implicit, orbit-averaged, time-space-centered finite difference scheme is employed in both the 1D Darwin field equations (in potential form) and the 1D-3V particle orbit equations to produce a discrete system that remains exactly charge- and energy-conserving. Furthermore, enabled by the implicit Darwin equations, exact conservation of the canonical momentum per particle in any ignorable direction is enforced via a suitable scattering rule for the magnetic field. We have developed a simple preconditioner that targets electrostatic waves and skin currents, and allows us to employ time steps O(√{mi /me } c /veT) larger than the explicit CFL. Several 1D numerical experiments demonstrate the accuracy, performance, and conservation properties of the algorithm. In particular, the scheme is shown to be second-order accurate, and CPU speedups of more than three orders of magnitude vs. an explicit Vlasov-Maxwell solver are demonstrated in the "cold" plasma regime (where kλD ≪ 1).

  1. How the Brain Decides When to Work and When to Rest: Dissociation of Implicit-Reactive from Explicit-Predictive Computational Processes

    PubMed Central

    Meyniel, Florent; Safra, Lou; Pessiglione, Mathias

    2014-01-01

    A pervasive case of cost-benefit problem is how to allocate effort over time, i.e. deciding when to work and when to rest. An economic decision perspective would suggest that duration of effort is determined beforehand, depending on expected costs and benefits. However, the literature on exercise performance emphasizes that decisions are made on the fly, depending on physiological variables. Here, we propose and validate a general model of effort allocation that integrates these two views. In this model, a single variable, termed cost evidence, accumulates during effort and dissipates during rest, triggering effort cessation and resumption when reaching bounds. We assumed that such a basic mechanism could explain implicit adaptation, whereas the latent parameters (slopes and bounds) could be amenable to explicit anticipation. A series of behavioral experiments manipulating effort duration and difficulty was conducted in a total of 121 healthy humans to dissociate implicit-reactive from explicit-predictive computations. Results show 1) that effort and rest durations are adapted on the fly to variations in cost-evidence level, 2) that the cost-evidence fluctuations driving the behavior do not match explicit ratings of exhaustion, and 3) that actual difficulty impacts effort duration whereas expected difficulty impacts rest duration. Taken together, our findings suggest that cost evidence is implicitly monitored online, with an accumulation rate proportional to actual task difficulty. In contrast, cost-evidence bounds and dissipation rate might be adjusted in anticipation, depending on explicit task difficulty. PMID:24743711

  2. An implicit higher-order spatially accurate scheme for solving time dependent flows on unstructured meshes

    NASA Astrophysics Data System (ADS)

    Tomaro, Robert F.

    1998-07-01

    The present research is aimed at developing a higher-order, spatially accurate scheme for both steady and unsteady flow simulations using unstructured meshes. The resulting scheme must work on a variety of general problems to ensure the creation of a flexible, reliable and accurate aerodynamic analysis tool. To calculate the flow around complex configurations, unstructured grids and the associated flow solvers have been developed. Efficient simulations require the minimum use of computer memory and computational times. Unstructured flow solvers typically require more computer memory than a structured flow solver due to the indirect addressing of the cells. The approach taken in the present research was to modify an existing three-dimensional unstructured flow solver to first decrease the computational time required for a solution and then to increase the spatial accuracy. The terms required to simulate flow involving non-stationary grids were also implemented. First, an implicit solution algorithm was implemented to replace the existing explicit procedure. Several test cases, including internal and external, inviscid and viscous, two-dimensional, three-dimensional and axi-symmetric problems, were simulated for comparison between the explicit and implicit solution procedures. The increased efficiency and robustness of modified code due to the implicit algorithm was demonstrated. Two unsteady test cases, a plunging airfoil and a wing undergoing bending and torsion, were simulated using the implicit algorithm modified to include the terms required for a moving and/or deforming grid. Secondly, a higher than second-order spatially accurate scheme was developed and implemented into the baseline code. Third- and fourth-order spatially accurate schemes were implemented and tested. The original dissipation was modified to include higher-order terms and modified near shock waves to limit pre- and post-shock oscillations. The unsteady cases were repeated using the higher-order spatially accurate code. The new solutions were compared with those obtained using the second-order spatially accurate scheme. Finally, the increased efficiency of using an implicit solution algorithm in a production Computational Fluid Dynamics flow solver was demonstrated for steady and unsteady flows. A third- and fourth-order spatially accurate scheme has been implemented creating a basis for a state-of-the-art aerodynamic analysis tool.

  3. Fitts' Law in the Control of Isometric Grip Force With Naturalistic Targets.

    PubMed

    Thumser, Zachary C; Slifkin, Andrew B; Beckler, Dylan T; Marasco, Paul D

    2018-01-01

    Fitts' law models the relationship between amplitude, precision, and speed of rapid movements. It is widely used to quantify performance in pointing tasks, study human-computer interaction, and generally to understand perceptual-motor information processes, including research to model performance in isometric force production tasks. Applying Fitts' law to an isometric grip force task would allow for quantifying grasp performance in rehabilitative medicine and may aid research on prosthetic control and design. We examined whether Fitts' law would hold when participants attempted to accurately produce their intended force output while grasping a manipulandum when presented with images of various everyday objects (we termed this the implicit task). Although our main interest was the implicit task, to benchmark it and establish validity, we examined performance against a more standard visual feedback condition via a digital force-feedback meter on a video monitor (explicit task). Next, we progressed from visual force feedback with force meter targets to the same targets without visual force feedback (operating largely on feedforward control with tactile feedback). This provided an opportunity to see if Fitts' law would hold without vision, and allowed us to progress toward the more naturalistic implicit task (which does not include visual feedback). Finally, we changed the nature of the targets from requiring explicit force values presented as arrows on a force-feedback meter (explicit targets) to the more naturalistic and intuitive target forces implied by images of objects (implicit targets). With visual force feedback the relation between task difficulty and the time to produce the target grip force was predicted by Fitts' law (average r 2 = 0.82). Without vision, average grip force scaled accurately although force variability was insensitive to the target presented. In contrast, images of everyday objects generated more reliable grip forces without the visualized force meter. In sum, population means were well-described by Fitts' law for explicit targets with vision ( r 2 = 0.96) and implicit targets ( r 2 = 0.89), but not as well-described for explicit targets without vision ( r 2 = 0.54). Implicit targets should provide a realistic see-object-squeeze-object test using Fitts' law to quantify the relative speed-accuracy relationship of any given grasper.

  4. A Framework for Integrating Implicit Bias Recognition Into Health Professions Education.

    PubMed

    Sukhera, Javeed; Watling, Chris

    2018-01-01

    Existing literature on implicit bias is fragmented and comes from a variety of fields like cognitive psychology, business ethics, and higher education, but implicit-bias-informed educational approaches have been underexplored in health professions education and are difficult to evaluate using existing tools. Despite increasing attention to implicit bias recognition and management in health professions education, many programs struggle to meaningfully integrate these topics into curricula. The authors propose a six-point actionable framework for integrating implicit bias recognition and management into health professions education that draws on the work of previous researchers and includes practical tools to guide curriculum developers. The six key features of this framework are creating a safe and nonthreatening learning context, increasing knowledge about the science of implicit bias, emphasizing how implicit bias influences behaviors and patient outcomes, increasing self-awareness of existing implicit biases, improving conscious efforts to overcome implicit bias, and enhancing awareness of how implicit bias influences others. Important considerations for designing implicit-bias-informed curricula-such as individual and contextual variables, as well as formal and informal cultural influences-are discussed. The authors also outline assessment and evaluation approaches that consider outcomes at individual, organizational, community, and societal levels. The proposed framework may facilitate future research and exploration regarding the use of implicit bias in health professions education.

  5. A decade of studying implicit racial/ethnic bias in healthcare providers using the implicit association test.

    PubMed

    Maina, Ivy W; Belton, Tanisha D; Ginzberg, Sara; Singh, Ajit; Johnson, Tiffani J

    2018-02-01

    Disparities in the care and outcomes of US racial/ethnic minorities are well documented. Research suggests that provider bias plays a role in these disparities. The implicit association test enables measurement of implicit bias via tests of automatic associations between concepts. Hundreds of studies have examined implicit bias in various settings, but relatively few have been conducted in healthcare. The aim of this systematic review is to synthesize the current knowledge on the role of implicit bias in healthcare disparities. A comprehensive literature search of several databases between May 2015 and September 2016 identified 37 qualifying studies. Of these, 31 found evidence of pro-White or light-skin/anti-Black, Hispanic, American Indian or dark-skin bias among a variety of HCPs across multiple levels of training and disciplines. Fourteen studies examined the association between implicit bias and healthcare outcomes using clinical vignettes or simulated patients. Eight found no statistically significant association between implicit bias and patient care while six studies found that higher implicit bias was associated with disparities in treatment recommendations, expectations of therapeutic bonds, pain management, and empathy. All seven studies that examined the impact of implicit provider bias on real-world patient-provider interaction found that providers with stronger implicit bias demonstrated poorer patient-provider communication. Two studies examined the effect of implicit bias on real-world clinical outcomes. One found an association and the other did not. Two studies tested interventions aimed at reducing bias, but only one found a post-intervention reduction in implicit bias. This review reveals a need for more research exploring implicit bias in real-world patient care, potential modifiers and confounders of the effect of implicit bias on care, and strategies aimed at reducing implicit bias and improving patient-provider communication. Future studies have the opportunity to build on this current body of research, and in doing so will enable us to achieve equity in healthcare and outcomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Domain-general sequence learning deficit in specific language impairment.

    PubMed

    Lukács, Agnes; Kemény, Ferenc

    2014-05-01

    Grammar-specific accounts of specific language impairment (SLI) have been challenged by recent claims that language problems are a consequence of impairments in domain-general mechanisms of learning that also play a key role in the process of language acquisition. Our studies were designed to test the generality and nature of this learning deficit by focusing on both sequential and nonsequential, and on verbal and nonverbal, domains. Twenty-nine children with SLI were compared with age-matched typically developing (TD) control children using (a) a serial reaction time task (SRT), testing the learning of motor sequences; (b) an artificial grammar learning (AGL) task, testing the extraction of regularities from auditory sequences; and (c) a weather prediction task (WP), testing probabilistic category learning in a nonsequential task. For the 2 sequence learning tasks, a significantly smaller proportion of children showed evidence of learning in the SLI than in the TD group (χ2 tests, p < .001 for the SRT task, p < .05 for the AGL task), whereas the proportion of learners on the WP task was the same in the 2 groups. The level of learning for SLI learners was comparable with that of TD children on all tasks (with great individual variation). Taken together, these findings suggest that domain-general processes of implicit sequence learning tend to be impaired in SLI. Further research is needed to clarify the relationship of deficits in implicit learning and language.

  7. The evaluation of a shuttle borne lidar experiment to measure the global distribution of aerosols and their effect on the atmospheric heat budget

    NASA Technical Reports Server (NTRS)

    Shipley, S. T.; Joseph, J. H.; Trauger, J. T.; Guetter, P. J.; Eloranta, E. W.; Lawler, J. E.; Wiscombe, W. J.; Odell, A. P.; Roesler, F. L.; Weinman, J. A.

    1975-01-01

    A shuttle-borne lidar system is described, which will provide basic data about aerosol distributions for developing climatological models. Topics discussed include: (1) present knowledge of the physical characteristics of desert aerosols and the absorption characteristics of atmospheric gas, (2) radiative heating computations, and (3) general circulation models. The characteristics of a shuttle-borne radar are presented along with some laboratory studies which identify schemes that permit the implementation of a high spectral resolution lidar system.

  8. Neurological development of children born to mothers after kidney transplantation.

    PubMed

    Schreiber-Zamora, Joanna; Szpotanska-Sikorska, Monika; Drozdowska-Szymczak, Agnieszka; Czaplinska, Natalia; Pietrzak, Bronisława; Wielgos, Miroslaw; Kociszewska-Najman, Bozena

    2017-12-03

    Pregnancies after kidney transplantation are at high risk of complications such as preterm birth and foetal growth restriction. Until now, the impact of these factors on neurological development of children born to transplant mothers has not been established. A comparison of neurological examinations performed in 36 children of kidney transplant women (study group) and 36 children born to healthy mothers (control group). The children from both groups were born at a similar gestational age and in the similar time period from 12/1996 to 09/2012. Neurological examinations were performed from 07/2010 to 11/2013. Each examination was adjusted to the patient's age and performed after the neonatal period. Three years later children were re-consulted, if they presented neurological deviations or were less than 12 months old at the time of the first examination. Normal neurological development was found in 86% of children in both groups (p = .999). Mild neurological deviations were observed in four (11%) children born to kidney transplant mothers and in five (14%) children born to healthy mothers (p = .999). Moderate deviations were diagnosed in one premature child born to transplant mother, whose pregnancy was complicated with a severe preeclampsia and foetal growth restriction. In the study population, no severe neurological disorders were found. Almost all (8/10) children with neurological deviations were born prematurely in good general conditions. The neurological deviations observed in the first year of life were mild and transient. In children over 1 year of age, deviations were more pronounced and continued to maintain. The neurological development of children of kidney transplant women is similar to that of the general population and possible deviations seem to be the result of intrauterine hypotrophy and prematurity. Therefore, in clinical practice, it is necessary to plan post-transplant pregnancies especially in women at high risk of these complications.

  9. Unconscious Motivation. Part I: Implicit Attitudes toward L2 Speakers

    ERIC Educational Resources Information Center

    Al-Hoorie, Ali H.

    2016-01-01

    This paper reports the first investigation in the second language acquisition field assessing learners' implicit attitudes using the Implicit Association Test, a computerized reaction-time measure. Examination of the explicit and implicit attitudes of Arab learners of English (N = 365) showed that, particularly for males, implicit attitudes toward…

  10. Persistence, Privilege, and Parenting: The Comparative Study of Intergenerational Mobility

    ERIC Educational Resources Information Center

    Smeeding, Timothy M., Ed.; Erikson, Robert, Ed.; Jantti, Markus, Ed.

    2011-01-01

    Americans like to believe that theirs is the land of opportunity, but the hard facts are that children born into poor families in the United States tend to stay poor and children born into wealthy families generally stay rich. Other countries have shown more success at lessening the effects of inequality on mobility--possibly by making public…

  11. Explicit and Implicit Subject Bias in the "ABS Journal Quality Guide"

    ERIC Educational Resources Information Center

    Hoepner, Andreas G. F.; Unerman, Jeffrey

    2012-01-01

    This paper addresses issues raised in two recent papers published in this journal about the UK "Association of Business Schools' Journal Quality Guide (ABS Guide)". While much of the debate about journal rankings in general, and the "ABS Guide" in particular, has focused on the construction, power and (mis)use of these…

  12. Identity Bargaining: A Policy Systems Research Model of Career Development.

    ERIC Educational Resources Information Center

    Slawski, Carl

    A detailed, general and comprehensive accounting scheme is presented, consisting of nine stages of career development, three major sets of elements contributing to career choice (in terms of personal, cultural and situational roles), and 20 hypotheses relating the separate elements. Implicit in the model is a novel procedure and method for…

  13. The Anatomy and Ideology of a Charter

    ERIC Educational Resources Information Center

    Fife, Brian L.

    2008-01-01

    A content analysis of charter school movements was conducted in order to gain insight on their substantive contents as well as to discern any explicit or implicit ideological underpinnings. Charter agreements in Indiana were obtained over a three year period of time, shortly after the Indiana General Assembly sanctioned the creation of charter…

  14. Taming the Warrant in Toulmin's Model of Argument

    ERIC Educational Resources Information Center

    Warren, James E.

    2010-01-01

    In the Toulmin model, arguments begin with a "claim" supported by "data." The movement from claim to data is authorized by a general, unstated proposition Stephen E. Toulmin calls the "warrant." Unlike all other components of the Toulmin model, warrants usually remain implicit in an argument; they are the unspoken assumptions that bind together…

  15. Implicit and Explicit Preference Structures in Models of Labor Supply.

    ERIC Educational Resources Information Center

    Dickinson, Jonathan

    The study of labor supply is directed to a theoretical methodology under which the choice of the general functional form of the income-leisure preference structure may be regarded as an empirical question. The author has reviewed the common functional forms employed in empirical labor supply models and has characterized the inherent preference…

  16. Racial-Ethnic Biases, Time Pressure, and Medical Decisions

    ERIC Educational Resources Information Center

    Stepanikova, Irena

    2012-01-01

    This study examined two types of potential sources of racial-ethnic disparities in medical care: implicit biases and time pressure. Eighty-one family physicians and general internists responded to a case vignette describing a patient with chest pain. Time pressure was manipulated experimentally. Under high time pressure, but not under low time…

  17. Sex Influences on the Neurobiology of Learning and Memory

    ERIC Educational Resources Information Center

    Andreano, Joseph M.; Cahill, Larry

    2009-01-01

    In essentially every domain of neuroscience, the generally implicit assumption that few, if any, meaningful differences exist between male and female brain function is being challenged. Here we address how this development is influencing studies of the neurobiology of learning and memory. While it has been commonly held that males show an…

  18. Family Poicy in Canada: Some Theoretical Considerations and a Practical Application.

    ERIC Educational Resources Information Center

    Hepworth, H. Philip

    Frequently implicit in Canadian social policy addressing other issues, family policy is generally assumed to be a good thing, is bound up with social structure, and, when made explicit, is prescriptive and potentially embarrassing to government. Historically important as a forerunner of more recent income assistance programs, the provision of…

  19. Accuracy assessment of the linear Poisson-Boltzmann equation and reparametrization of the OBC generalized Born model for nucleic acids and nucleic acid-protein complexes.

    PubMed

    Fogolari, Federico; Corazza, Alessandra; Esposito, Gennaro

    2015-04-05

    The generalized Born model in the Onufriev, Bashford, and Case (Onufriev et al., Proteins: Struct Funct Genet 2004, 55, 383) implementation has emerged as one of the best compromises between accuracy and speed of computation. For simulations of nucleic acids, however, a number of issues should be addressed: (1) the generalized Born model is based on a linear model and the linearization of the reference Poisson-Boltmann equation may be questioned for highly charged systems as nucleic acids; (2) although much attention has been given to potentials, solvation forces could be much less sensitive to linearization than the potentials; and (3) the accuracy of the Onufriev-Bashford-Case (OBC) model for nucleic acids depends on fine tuning of parameters. Here, we show that the linearization of the Poisson Boltzmann equation has mild effects on computed forces, and that with optimal choice of the OBC model parameters, solvation forces, essential for molecular dynamics simulations, agree well with those computed using the reference Poisson-Boltzmann model. © 2015 Wiley Periodicals, Inc.

  20. Comparison of Implicit Schemes for the Incompressible Navier-Stokes Equations

    NASA Technical Reports Server (NTRS)

    Rogers, Stuart E.

    1995-01-01

    For a computational flow simulation tool to be useful in a design environment, it must be very robust and efficient. To develop such a tool for incompressible flow applications, a number of different implicit schemes are compared for several two-dimensional flow problems in the current study. The schemes include Point-Jacobi relaxation, Gauss-Seidel line relaxation, incomplete lower-upper decomposition, and the generalized minimum residual method preconditioned with each of the three other schemes. The efficiency of the schemes is measured in terms of the computing time required to obtain a steady-state solution for the laminar flow over a backward-facing step, the flow over a NACA 4412 airfoil, and the flow over a three-element airfoil using overset grids. The flow solver used in the study is the INS2D code that solves the incompressible Navier-Stokes equations using the method of artificial compressibility and upwind differencing of the convective terms. The results show that the generalized minimum residual method preconditioned with the incomplete lower-upper factorization outperforms all other methods by at least a factor of 2.

  1. Implicit time-marching solution of the Navier-Stokes equations for thrust reversing and thrust vectoring nozzle flows

    NASA Technical Reports Server (NTRS)

    Imlay, S. T.

    1986-01-01

    An implicit finite volume method is investigated for the solution of the compressible Navier-Stokes equations for flows within thrust reversing and thrust vectoring nozzles. Thrust reversing nozzles typically have sharp corners, and the rapid expansion and large turning angles near these corners are shown to cause unacceptable time step restrictions when conventional approximate factorization methods are used. In this investigation these limitations are overcome by using second-order upwind differencing and line Gauss-Siedel relaxation. This method is implemented with a zonal mesh so that flows through complex nozzle geometries may be efficiently calculated. Results are presented for five nozzle configurations including two with time varying geometries. Three cases are compared with available experimental data and the results are generally acceptable.

  2. 2-dimensional implicit hydrodynamics on adaptive grids

    NASA Astrophysics Data System (ADS)

    Stökl, A.; Dorfi, E. A.

    2007-12-01

    We present a numerical scheme for two-dimensional hydrodynamics computations using a 2D adaptive grid together with an implicit discretization. The combination of these techniques has offered favorable numerical properties applicable to a variety of one-dimensional astrophysical problems which motivated us to generalize this approach for two-dimensional applications. Due to the different topological nature of 2D grids compared to 1D problems, grid adaptivity has to avoid severe grid distortions which necessitates additional smoothing parameters to be included into the formulation of a 2D adaptive grid. The concept of adaptivity is described in detail and several test computations demonstrate the effectivity of smoothing. The coupled solution of this grid equation together with the equations of hydrodynamics is illustrated by computation of a 2D shock tube problem.

  3. Development of iterative techniques for the solution of unsteady compressible viscous flows

    NASA Technical Reports Server (NTRS)

    Sankar, Lakshmi N.; Hixon, Duane

    1992-01-01

    The development of efficient iterative solution methods for the numerical solution of two- and three-dimensional compressible Navier-Stokes equations is discussed. Iterative time marching methods have several advantages over classical multi-step explicit time marching schemes, and non-iterative implicit time marching schemes. Iterative schemes have better stability characteristics than non-iterative explicit and implicit schemes. In this work, another approach based on the classical conjugate gradient method, known as the Generalized Minimum Residual (GMRES) algorithm is investigated. The GMRES algorithm has been used in the past by a number of researchers for solving steady viscous and inviscid flow problems. Here, we investigate the suitability of this algorithm for solving the system of non-linear equations that arise in unsteady Navier-Stokes solvers at each time step.

  4. Are implicit self-esteem measures valid for assessing individual and cultural differences?

    PubMed

    Falk, Carl F; Heine, Steven J; Takemura, Kosuke; Zhang, Cathy X J; Hsu, Chih-Wei

    2015-02-01

    Our research utilized two popular theoretical conceptualizations of implicit self-esteem: 1) implicit self-esteem as a global automatic reaction to the self; and 2) implicit self-esteem as a context/domain specific construct. Under this framework, we present an extensive search for implicit self-esteem measure validity among different cultural groups (Study 1) and under several experimental manipulations (Study 2). In Study 1, Euro-Canadians (N = 107), Asian-Canadians (N = 187), and Japanese (N = 112) completed a battery of implicit self-esteem, explicit self-esteem, and criterion measures. Included implicit self-esteem measures were either popular or provided methodological improvements upon older methods. Criterion measures were sampled from previous research on implicit self-esteem and included self-report and independent ratings. In Study 2, Americans (N = 582) completed a shorter battery of these same types of measures under either a control condition, an explicit prime meant to activate the self-concept in a particular context, or prime meant to activate self-competence related implicit attitudes. Across both studies, explicit self-esteem measures far outperformed implicit self-esteem measures in all cultural groups and under all experimental manipulations. Implicit self-esteem measures are not valid for individual or cross-cultural comparisons. We speculate that individuals may not form implicit associations with the self as an attitudinal object. © 2013 Wiley Periodicals, Inc.

  5. Implicit self-esteem decreases in adolescence: a cross-sectional study.

    PubMed

    Cai, Huajian; Wu, Mingzheng; Luo, Yu L L; Yang, Jing

    2014-01-01

    Implicit self-esteem has remained an active research topic in both the areas of implicit social cognition and self-esteem in recent decades. The purpose of this study is to explore the development of implicit self-esteem in adolescents. A total of 599 adolescents from junior and senior high schools in East China participated in the study. They ranged in age from 11 to 18 years with a mean age of 14.10 (SD = 2.16). The degree of implicit self-esteem was assessed using the Implicit Association Test (IAT) with the improved D score as the index. Participants also completed the Rosenberg Self-Esteem Scale (α = 0.77). For all surveyed ages, implicit self-esteem was positively biased, all ts>8.59, all ps<0.001. The simple correlation between implicit self-esteem and age was significant, r =  -.25, p = 1. 10(-10). A regression with implicit self-esteem as the criterion variable, and age, gender, and age × gender interaction as predictors further revealed the significant negative linear relationship between age and implicit self-esteem, β = -0.19, t = -3.20, p = 0.001. However, explicit self-esteem manifested a reverse "U" shape throughout adolescence. Implicit self-esteem in adolescence manifests a declining trend with increasing age, suggesting that it is sensitive to developmental or age-related changes. This finding enriches our understanding of the development of implicit social cognition.

  6. Patient-centered care, nurse work environment and implicit rationing of nursing care in Swiss acute care hospitals: A cross-sectional multi-center study.

    PubMed

    Bachnick, Stefanie; Ausserhofer, Dietmar; Baernholdt, Marianne; Simon, Michael

    2018-05-01

    Patient-centered care is a key element of high-quality healthcare and determined by individual, structural and process factors. Patient-centered care is associated with improved patient-reported, clinical and economic outcomes. However, while hospital-level characteristics influence patient-centered care, little evidence is available on the association of patient-centered care with characteristic such as the nurse work environment or implicit rationing of nursing care. The aim of this study was to describe patient-centered care in Swiss acute care hospitals and to explore the associations with nurse work environment factors and implicit rationing of nursing care. This is a sub-study of the cross-sectional multi-center "Matching Registered Nurse Services with Changing Care Demands" study. We included 123 units in 23 acute care hospitals from all three of Switzerland's language regions. The sample consisted of 2073 patients, hospitalized for at least 24 h and ≥18 years of age. From the same hospital units, 1810 registered nurses working in direct patient care were also included. Patients' perceptions of patient-centered care were assessed using four items from the Generic Short Patient Experiences Questionnaire. Nurses completed questionnaires assessing perceived staffing and resource adequacy, adjusted staffing, leadership ability and level of implicit rationing of nursing care. We applied a Generalized Linear Mixed Models for analysis including individual-level patient and nurse data aggregated to the unit level. Patients reported high levels of patient-centered care: 90% easily understood nurses, 91% felt the treatment and care were adapted for their situation, 82% received sufficient information, and 70% felt involved in treatment and care decisions. Higher staffing and resource adequacy was associated with higher levels of patient-centered care, e.g., sufficient information (β 0.638 [95%-CI: 0.30-0.98]). Higher leadership ratings were associated with sufficient information (β 0.403 [95%-CI: 0.03-0.77) and adapted treatment and care (β 0.462 [95%-CI: 0.04-0.88]). Furthermore, higher levels of implicit rationing of nursing care were associated with lower levels of patient-centered care, e.g., adapted treatment and care (β -0.912 [95%-CI: -1.50-0.33]). Our study shows a negative association between implicit rationing of nursing care and patient-centered care: i.e.the lower the level of implicit rationing of nursing care, the better patients understood nurses, felt sufficiently informed and recognized that they were receiving highly individualized treatment. To improve patient-centered care, the nurse work environment and the level of implicit rationing of nursing care should be taken into consideration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Using Implicit Measures to Highlight Science Teachers' Implicit Theories of Intelligence

    ERIC Educational Resources Information Center

    Mascret, Nicolas; Roussel, Peggy; Cury, François

    2015-01-01

    Using an innovative method, a Single-Target Implicit Association Test (ST-IAT) was created to explore the implicit theories of intelligence among science and liberal arts teachers and their relationships with their gender. The results showed that for science teachers--especially for male teachers--there was a negative implicit association between…

  8. The Roles of Implicit Understanding of Engineering Ethics in Student Teams' Discussion.

    PubMed

    Lee, Eun Ah; Grohman, Magdalena; Gans, Nicholas R; Tacca, Marco; Brown, Matthew J

    2017-12-01

    Following previous work that shows engineering students possess different levels of understanding of ethics-implicit and explicit-this study focuses on how students' implicit understanding of engineering ethics influences their team discussion process, in cases where there is significant divergence between their explicit and implicit understanding. We observed student teams during group discussions of the ethical issues involved in their engineering design projects. Through the micro-scale discourse analysis based on cognitive ethnography, we found two possible ways in which implicit understanding influenced the discussion. In one case, implicit understanding played the role of intuitive ethics-an intuitive judgment followed by reasoning. In the other case, implicit understanding played the role of ethical insight, emotionally guiding the direction of the discussion. In either case, however, implicit understanding did not have a strong influence, and the conclusion of the discussion reflected students' explicit understanding. Because students' implicit understanding represented broader social implication of engineering design in both cases, we suggest to take account of students' relevant implicit understanding in engineering education, to help students become more socially responsible engineers.

  9. Assessment of implicit health attitudes: a multitrait-multimethod approach and a comparison between patients with hypochondriasis and patients with anxiety disorders.

    PubMed

    Weck, Florian; Höfling, Volkmar

    2015-01-01

    Two adaptations of the Implicit Association Task were used to assess implicit anxiety (IAT-Anxiety) and implicit health attitudes (IAT-Hypochondriasis) in patients with hypochondriasis (n = 58) and anxiety patients (n = 71). Explicit anxieties and health attitudes were assessed using questionnaires. The analysis of several multitrait-multimethod models indicated that the low correlation between explicit and implicit measures of health attitudes is due to the substantial methodological differences between the IAT and the self-report questionnaire. Patients with hypochondriasis displayed significantly more dysfunctional explicit and implicit health attitudes than anxiety patients, but no differences were found regarding explicit and implicit anxieties. The study demonstrates the specificity of explicit and implicit dysfunctional health attitudes among patients with hypochondriasis.

  10. Common mental disorders in primary health care: differences between Latin American-born and Spanish-born residents in Madrid, Spain.

    PubMed

    Salinero-Fort, Miguel A; Jiménez-García, Rodrigo; de Burgos-Lunar, Carmen; Chico-Moraleja, Rosa M; Gómez-Campelo, Paloma

    2015-03-01

    Our main objective was to estimate and compare the prevalence of the most common mental disorders between Latin American-born and Spanish-born patients in Madrid, Spain. We also analyzed sociodemographic factors associated with these disorders and the role of the length of residency for Latin American-born patients. We performed a cross-sectional study to compare Latin American-born (n = 691) and Spanish-born outpatients (n = 903) from 15 primary health care centers in Madrid, Spain. The Primary Care Evaluation of Mental Disorders was used to diagnose common mental disorders. Sociodemographic, psychosocial, and migration data were collected. We detected common mental disorders in 49.9 % (95 % CI = 47.4-52.3 %) of the total sample. Values were higher in Latin American-born patients than in Spanish-born patients for any disorder (57.8 % vs. 43.9 %, p < 0.001), mood disorders (40.1 % vs. 34.8 %, p = 0.030), anxiety disorders (20.5 % vs. 15.3 %, p = 0.006), and somatoform disorders (18.1 % vs. 6.6 %, p < 0.001). There were no statistically significant differences in prevalence between Latin American-born patients with less than 5 years of residency and Latin American-born residents with 5 or more years of residency. Finally, multivariate analysis shows that gender, having/not having children, monthly income, geographic origin, and social support were significantly associated with several disorders. The sample was neither population-based nor representative of the general immigrant or autochthonous populations. The study provides further evidence of the high prevalence of common mental disorders in Latin American-born patients in Spain compared with Spanish-born patients.

  11. Can implicit appraisal concepts produce emotion-specific effects? A focus on unfairness and anger.

    PubMed

    Tong, Eddie M W; Tan, Deborah H; Tan, Yan Lin

    2013-06-01

    This research examined whether the non-conscious activation of an implicit appraisal concept could affect responses associated with the corresponding emotion as predicted by appraisal theories. Explicit and implicit emotional responses were examined. We focused on implicit unfairness and its effect on anger. The results show that subliminal activation of implicit unfairness affected implicit anger responses (anger facial expression and latency responses to anger words) but not explicit anger feelings (i.e., reported anger). The non-conscious effect of implicit unfairness was specific to anger, as no effect on sadness, fear, and guilt was found. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. The Intergenerational Transmission of Implicit and Explicit Attitudes Toward Smoking

    PubMed Central

    Sherman, Steven J.; Chassin, Laurie; Presson, Clark; Seo, Dong-Chul; Macy, Jonathan T.

    2009-01-01

    This study examined the intergenerational transmission of implicit and explicit attitudes toward smoking, as well as the role of these attitudes in adolescents’ smoking initiation. There was evidence of intergenerational transmission of implicit attitudes. Mothers who had more positive implicit attitudes had children with more positive implicit attitudes. In turn, these positive implicit attitudes of adolescents predicted their smoking initiation 18-months later. Moreover, these effects were obtained above and beyond the effects of explicit attitudes. These findings provide the first evidence that the intergenerational transmission of implicit cognition may play a role in the intergenerational transmission of an addictive behavior. PMID:20126293

  13. On the nature of implicit soul beliefs: when the past weighs more than the present.

    PubMed

    Anglin, Stephanie M

    2015-06-01

    Intuitive childhood beliefs in dualism may lay the foundation for implicit soul and afterlife beliefs, which may diverge from explicit beliefs formed later in adulthood. Brief Implicit Association Tests were developed to investigate the relation of implicit soul and afterlife beliefs to childhood and current beliefs. Early but not current beliefs covaried with implicit beliefs. Results demonstrated greater discrepancies in current than in childhood soul and afterlife beliefs among religious groups, and no differences in implicit beliefs. These findings suggest that implicit soul and afterlife beliefs diverge from current self-reported beliefs, stemming instead from childhood beliefs. © 2014 The British Psychological Society.

  14. An Optimized Multicolor Point-Implicit Solver for Unstructured Grid Applications on Graphics Processing Units

    NASA Technical Reports Server (NTRS)

    Zubair, Mohammad; Nielsen, Eric; Luitjens, Justin; Hammond, Dana

    2016-01-01

    In the field of computational fluid dynamics, the Navier-Stokes equations are often solved using an unstructuredgrid approach to accommodate geometric complexity. Implicit solution methodologies for such spatial discretizations generally require frequent solution of large tightly-coupled systems of block-sparse linear equations. The multicolor point-implicit solver used in the current work typically requires a significant fraction of the overall application run time. In this work, an efficient implementation of the solver for graphics processing units is proposed. Several factors present unique challenges to achieving an efficient implementation in this environment. These include the variable amount of parallelism available in different kernel calls, indirect memory access patterns, low arithmetic intensity, and the requirement to support variable block sizes. In this work, the solver is reformulated to use standard sparse and dense Basic Linear Algebra Subprograms (BLAS) functions. However, numerical experiments show that the performance of the BLAS functions available in existing CUDA libraries is suboptimal for matrices representative of those encountered in actual simulations. Instead, optimized versions of these functions are developed. Depending on block size, the new implementations show performance gains of up to 7x over the existing CUDA library functions.

  15. An Implicit Upwind Algorithm for Computing Turbulent Flows on Unstructured Grids

    NASA Technical Reports Server (NTRS)

    Anerson, W. Kyle; Bonhaus, Daryl L.

    1994-01-01

    An implicit, Navier-Stokes solution algorithm is presented for the computation of turbulent flow on unstructured grids. The inviscid fluxes are computed using an upwind algorithm and the solution is advanced in time using a backward-Euler time-stepping scheme. At each time step, the linear system of equations is approximately solved with a point-implicit relaxation scheme. This methodology provides a viable and robust algorithm for computing turbulent flows on unstructured meshes. Results are shown for subsonic flow over a NACA 0012 airfoil and for transonic flow over a RAE 2822 airfoil exhibiting a strong upper-surface shock. In addition, results are shown for 3 element and 4 element airfoil configurations. For the calculations, two one equation turbulence models are utilized. For the NACA 0012 airfoil, a pressure distribution and force data are compared with other computational results as well as with experiment. Comparisons of computed pressure distributions and velocity profiles with experimental data are shown for the RAE airfoil and for the 3 element configuration. For the 4 element case, comparisons of surface pressure distributions with experiment are made. In general, the agreement between the computations and the experiment is good.

  16. A Paradigm to Assess Implicit Attitudes towards God: The Positive/Negative God Associations Task.

    PubMed

    Pirutinsky, Steven; Carp, Sean; Rosmarin, David H

    2017-02-01

    Psychological research on the relationship between spirituality/religion and mental health has grown considerably over the past several decades and now constitutes a sizable body of scholarship. Among dimensions of S/R, positive beliefs about God have been significantly related to better mental health outcomes, and conversely negative beliefs about God are generally associated with more distress. However, prior research on this topic has relied heavily upon self-report Likert-type scales, which are vulnerable to self-report biases and measure only explicit cognitive processes. In this study, we developed and validated an implicit social cognition task, the Positive/Negative God Go/No-go Association Task (PNG-GNAT), for use in psychological research on spirituality and religion (S/R). Preliminary evidence in a large sample (N = 381) suggests that the PNG-GNAT demonstrates internal consistency, test-retest and split-half reliability, and concurrent evidence of validity. Further, our results suggest that PNG-GNAT scores represent different underlying dimensions of S/R than explicit self-report measures, and incrementally predict mental health above and beyond self-report assessment. The PNG-GNAT appears to be an effective tool for measuring implicit positive/negative beliefs about God.

  17. An Energy- and Charge-conserving, Implicit, Electrostatic Particle-in-Cell Algorithm in curvilinear geometry

    NASA Astrophysics Data System (ADS)

    Chen, G.; Chacón, L.; Barnes, D. C.

    2012-03-01

    A recent proof-of-principle study proposes an energy- and charge-conserving, fully implicit particle-in-cell algorithm in one dimension [1], which is able to use timesteps comparable to the dynamical timescale of interest. Here, we generalize the method to employ non-uniform meshes via a curvilinear map. The key enabling technology is a hybrid particle pusher [2], with particle positions updated in logical space and particle velocities updated in physical space. The self-adaptive, charge-conserving particle mover of Ref. [1] is extended to the non-uniform mesh case. The fully implicit implementation, using a Jacobian-free Newton-Krylov iterative solver, remains exactly charge- and energy-conserving. The extension of the formulation to multiple dimensions will be discussed. We present numerical experiments of 1D electrostatic, long-timescale ion-acoustic wave and ion-acoustic shock wave simulations, demonstrating that charge and energy are conserved to round-off for arbitrary mesh non-uniformity, and that the total momentum remains well conserved.[4pt] [1] Chen, Chac'on, Barnes, J. Comput. Phys. 230 (2011). [0pt] [2] Camporeale and Delzanno, Bull. Am. Phys. Soc. 56(6) (2011); Wang, et al., J. Plasma Physics, 61 (1999).

  18. Implicit Geometry Meshing for the simulation of Rotary Friction Welding

    NASA Astrophysics Data System (ADS)

    Schmicker, D.; Persson, P.-O.; Strackeljan, J.

    2014-08-01

    The simulation of Rotary Friction Welding (RFW) is a challenging task, since it states a coupled problem of phenomena like large plastic deformations, heat flux, contact and friction. In particular the mesh generation and its restoration when using a Lagrangian description of motion is of significant severity. In this regard Implicit Geometry Meshing (IGM) algorithms are promising alternatives to the more conventional explicit methods. Because of the implicit description of the geometry during remeshing, the IGM procedure turns out to be highly robust and generates spatial discretizations of high quality regardless of the complexity of the flash shape and its inclusions. A model for efficient RFW simulation is presented, which is based on a Carreau fluid law, an Augmented Lagrange approach in mapping the incompressible deformations, a penalty contact approach, a fully regularized Coulomb-/fluid friction law and a hybrid time integration strategy. The implementation of the IGM algorithm using 6-node triangular finite elements is described in detail. The techniques are demonstrated on a fairly complex friction welding problem, demonstrating the performance and the potentials of the proposed method. The techniques are general and straight-forward to implement, and offer the potential of successful adoption to a wide range of other engineering problems.

  19. Messages promoting genetic modification of crops in the context of climate change: Evidence for psychological reactance.

    PubMed

    Lu, Hang; McComas, Katherine A; Besley, John C

    2017-01-01

    Genetic modification (GM) of crops and climate change are arguably two of today's most challenging science communication issues. Increasingly, these two issues are connected in messages proposing GM as a viable option for ensuring global food security threatened by climate change. This study examines the effects of messages promoting the benefits of GM in the context of climate change. Further, it examines whether explicit reference to "climate change," or "global warming" in a GM message results in different effects than each other, or an implicit climate reference. An online sample of U.S. participants (N = 1050) were randomly assigned to one of four conditions: "climate change" cue, "global warming" cue, implicit cue, or control (no message). Generally speaking, framing GM crops as a way to help ensure global food security proved to be an effective messaging strategy in increasing positive attitudes toward GM. In addition, the implicit cue condition led to liberals having more positive attitudes and behavioral intentions toward GM than the "climate change" cue condition, an effect mediated by message evaluations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Implicit and Explicit Evaluation of Visual Symmetry as a Function of Art Expertise.

    PubMed

    Weichselbaum, Hanna; Leder, Helmut; Ansorge, Ulrich

    2018-01-01

    In perception, humans typically prefer symmetrical over asymmetrical patterns. Yet, little is known about differences in symmetry preferences depending on individuals' different past histories of actively reflecting upon pictures and patterns. To address this question, we tested the generality of the symmetry preference for different levels of individual art expertise. The preference for symmetrical versus asymmetrical abstract patterns was measured implicitly, by an Implicit Association Test (IAT), and explicitly, by a rating scale asking participants to evaluate pattern beauty. Participants were art history and psychology students. Art expertise was measured using a questionnaire. In the IAT, art expertise did not alter the preference for symmetrical over asymmetrical patterns. In contrast, the explicit rating scale showed that with higher art expertise, the ratings for the beauty of asymmetrical patterns significantly increased, but, again, participants preferred symmetrical over asymmetrical patterns. The results are discussed in light of different theories on the origins of symmetry preference. Evolutionary adaptation might play a role in symmetry preferences for art experts similarly to nonexperts, but experts tend to emphasize the beauty of asymmetrical depictions, eventually considering different criteria, when asked explicitly to indicate their preferences.

  1. Implicit and Explicit Evaluation of Visual Symmetry as a Function of Art Expertise

    PubMed Central

    Leder, Helmut; Ansorge, Ulrich

    2018-01-01

    In perception, humans typically prefer symmetrical over asymmetrical patterns. Yet, little is known about differences in symmetry preferences depending on individuals’ different past histories of actively reflecting upon pictures and patterns. To address this question, we tested the generality of the symmetry preference for different levels of individual art expertise. The preference for symmetrical versus asymmetrical abstract patterns was measured implicitly, by an Implicit Association Test (IAT), and explicitly, by a rating scale asking participants to evaluate pattern beauty. Participants were art history and psychology students. Art expertise was measured using a questionnaire. In the IAT, art expertise did not alter the preference for symmetrical over asymmetrical patterns. In contrast, the explicit rating scale showed that with higher art expertise, the ratings for the beauty of asymmetrical patterns significantly increased, but, again, participants preferred symmetrical over asymmetrical patterns. The results are discussed in light of different theories on the origins of symmetry preference. Evolutionary adaptation might play a role in symmetry preferences for art experts similarly to nonexperts, but experts tend to emphasize the beauty of asymmetrical depictions, eventually considering different criteria, when asked explicitly to indicate their preferences. PMID:29755722

  2. Sexual Inactivity During Young Adulthood Is More Common Among U.S. Millennials and iGen: Age, Period, and Cohort Effects on Having No Sexual Partners After Age 18.

    PubMed

    Twenge, Jean M; Sherman, Ryne A; Wells, Brooke E

    2017-02-01

    Examining age, time period, and cohort/generational changes in sexual experience is key to better understanding sociocultural influences on sexuality and relationships. Americans born in the 1980s and 1990s (commonly known as Millennials and iGen) were more likely to report having no sexual partners as adults compared to GenX'ers born in the 1960s and 1970s in the General Social Survey, a nationally representative sample of American adults (N = 26,707). Among those aged 20-24, more than twice as many Millennials born in the 1990s (15 %) had no sexual partners since age 18 compared to GenX'ers born in the 1960s (6 %). Higher rates of sexual inactivity among Millennials and iGen also appeared in analyses using a generalized hierarchical linear modeling technique known as age-period-cohort analysis to control for age and time period effects among adults of all ages. Americans born early in the 20th century also showed elevated rates of adult sexual inactivity. The shift toward higher rates of sexual inactivity among Millennials and iGen'ers was more pronounced among women and absent among Black Americans and those with a college education. Contrary to popular media conceptions of a "hookup generation" more likely to engage in frequent casual sex, a higher percentage of Americans in recent cohorts, particularly Millennials and iGen'ers born in the 1990s, had no sexual partners after age 18.

  3. Mapping Climate Change Vulnerabilities to Infectious Diseases in Europe

    PubMed Central

    Suk, Jonathan E.; Estevez, Virginia; Ebi, Kristie L.; Lindgren, Elisabet

    2011-01-01

    Background: The incidence, outbreak frequency, and distribution of many infectious diseases are generally expected to change as a consequence of climate change, yet there is limited regional information available to guide decision making. Objective: We surveyed government officials designated as Competent Bodies for Scientific Advice concerning infectious diseases to examine the degree to which they are concerned about potential effects of climate change on infectious diseases, as well as their perceptions of institutional capacities in their respective countries. Methods: In 2007 and 2009/2010, national infectious disease experts from 30 European Economic Area countries were surveyed about recent and projected infectious disease patterns in relation to climate change in their countries and the national capacity to cope with them. Results: A large majority of respondents agreed that climate change would affect vector-borne (86% of country representatives), food-borne (70%), water-borne (68%), and rodent-borne (68%) diseases in their countries. In addition, most indicated that institutional improvements are needed for ongoing surveillance programs (83%), collaboration with the veterinary sector (69%), management of animal disease outbreaks (66%), national monitoring and control of climate-sensitive infectious diseases (64%), health services during an infectious disease outbreak (61%), and diagnostic support during an epidemic (54%). Conclusions: Expert responses were generally consistent with the peer-reviewed literature regarding the relationship between climate change and vector- and water-borne diseases, but were less so for food-borne diseases. Shortcomings in institutional capacity to manage climate change vulnerability, identified in this assessment, should be addressed in impact, vulnerability, and adaptation assessments. PMID:22113877

  4. Changes of Explicit and Implicit Stigma in Medical Students during Psychiatric Clerkship.

    PubMed

    Wang, Peng-Wei; Ko, Chih-Hung; Chen, Cheng-Sheng; Yang, Yi-Hsin Connine; Lin, Huang-Chi; Cheng, Cheng-Chung; Tsang, Hin-Yeung; Wu, Ching-Kuan; Yen, Cheng-Fang

    2016-04-01

    This study examines the differences in explicit and implicit stigma between medical and non-medical undergraduate students at baseline; the changes of explicit and implicit stigma in medical undergraduate and non-medical undergraduate students after a 1-month psychiatric clerkship and 1-month follow-up period; and the differences in the changes of explicit and implicit stigma between medical and non-medical undergraduate students. Seventy-two medical undergraduate students and 64 non-medical undergraduate students were enrolled. All participants were interviewed at intake and after 1 month. The Taiwanese version of the Stigma Assessment Scale and the Implicit Association Test were used to measure the participants' explicit and implicit stigma. Neither explicit nor implicit stigma differed between two groups at baseline. The medical, but not the non-medical, undergraduate students had a significant decrease in explicit stigma during the 1-month period of follow-up. Neither the medical nor the non-medical undergraduate students exhibited a significant change in implicit stigma during the one-month of follow-up, however. There was an interactive effect between group and time on explicit stigma but not on implicit stigma. Explicit but not implicit stigma toward mental illness decreased in the medical undergraduate students after a psychiatric clerkship. Further study is needed to examine how to improve implicit stigma toward mental illness.

  5. Intact implicit learning in autism spectrum conditions.

    PubMed

    Brown, Jamie; Aczel, Balazs; Jiménez, Luis; Kaufman, Scott Barry; Grant, Kate Plaisted

    2010-09-01

    Individuals with autism spectrum condition (ASC) have diagnostic impairments in skills that are associated with an implicit acquisition; however, it is not clear whether ASC individuals show specific implicit learning deficits. We compared ASC and typically developing (TD) individuals matched for IQ on five learning tasks: four implicit learning tasks--contextual cueing, serial reaction time, artificial grammar learning, and probabilistic classification learning tasks--that used procedures expressly designed to minimize the use of explicit strategies, and one comparison explicit learning task, paired associates learning. We found implicit learning to be intact in ASC. Beyond no evidence of differences, there was evidence of statistical equivalence between the groups on all the implicit learning tasks. This was not a consequence of compensation by explicit learning ability or IQ. Furthermore, there was no evidence to relate implicit learning to ASC symptomatology. We conclude that implicit mechanisms are preserved in ASC and propose that it is disruption by other atypical processes that impact negatively on the development of skills associated with an implicit acquisition.

  6. The Relationship of Explicit-Implicit Evaluative Discrepancy to Exercise Dropout in Middle-Aged Adults.

    PubMed

    Berry, Tanya R; Rodgers, Wendy M; Divine, Alison; Hall, Craig

    2018-06-19

    Discrepancies between automatically activated associations (i.e., implicit evaluations) and explicit evaluations of motives (measured with a questionnaire) could lead to greater information processing to resolve discrepancies or self-regulatory failures that may affect behavior. This research examined the relationship of health and appearance exercise-related explicit-implicit evaluative discrepancies, the interaction between implicit and explicit evaluations, and the combined value of explicit and implicit evaluations (i.e., the summed scores) to dropout from a yearlong exercise program. Participants (N = 253) completed implicit health and appearance measures and explicit health and appearance motives at baseline, prior to starting the exercise program. The sum of implicit and explicit appearance measures was positively related to weeks in the program, and discrepancy between the implicit and explicit health measures was negatively related to length of time in the program. Implicit exercise evaluations and their relationships to oft-cited motives such as appearance and health may inform exercise dropout.

  7. Characteristic-based algorithms for flows in thermo-chemical nonequilibrium

    NASA Technical Reports Server (NTRS)

    Walters, Robert W.; Cinnella, Pasquale; Slack, David C.; Halt, David

    1990-01-01

    A generalized finite-rate chemistry algorithm with Steger-Warming, Van Leer, and Roe characteristic-based flux splittings is presented in three-dimensional generalized coordinates for the Navier-Stokes equations. Attention is placed on convergence to steady-state solutions with fully coupled chemistry. Time integration schemes including explicit m-stage Runge-Kutta, implicit approximate-factorization, relaxation and LU decomposition are investigated and compared in terms of residual reduction per unit of CPU time. Practical issues such as code vectorization and memory usage on modern supercomputers are discussed.

  8. Implicit Self-Esteem Decreases in Adolescence: A Cross-Sectional Study

    PubMed Central

    Cai, Huajian; Wu, Mingzheng; Luo, Yu L. L.; Yang, Jing

    2014-01-01

    Implicit self-esteem has remained an active research topic in both the areas of implicit social cognition and self-esteem in recent decades. The purpose of this study is to explore the development of implicit self-esteem in adolescents. A total of 599 adolescents from junior and senior high schools in East China participated in the study. They ranged in age from 11 to 18 years with a mean age of 14.10 (SD = 2.16). The degree of implicit self-esteem was assessed using the Implicit Association Test (IAT) with the improved D score as the index. Participants also completed the Rosenberg Self-Esteem Scale (α = 0.77). For all surveyed ages, implicit self-esteem was positively biased, all ts>8.59, all ps<0.001. The simple correlation between implicit self-esteem and age was significant, r = −.25, p = 1.0×10−10. A regression with implicit self-esteem as the criterion variable, and age, gender, and age × gender interaction as predictors further revealed the significant negative linear relationship between age and implicit self-esteem, β = −0.19, t = −3.20, p = 0.001. However, explicit self-esteem manifested a reverse “U” shape throughout adolescence. Implicit self-esteem in adolescence manifests a declining trend with increasing age, suggesting that it is sensitive to developmental or age-related changes. This finding enriches our understanding of the development of implicit social cognition. PMID:24587169

  9. Interpregnancy interval and risk of autistic disorder.

    PubMed

    Gunnes, Nina; Surén, Pål; Bresnahan, Michaeline; Hornig, Mady; Lie, Kari Kveim; Lipkin, W Ian; Magnus, Per; Nilsen, Roy Miodini; Reichborn-Kjennerud, Ted; Schjølberg, Synnve; Susser, Ezra Saul; Øyen, Anne-Siri; Stoltenberg, Camilla

    2013-11-01

    A recent California study reported increased risk of autistic disorder in children conceived within a year after the birth of a sibling. We assessed the association between interpregnancy interval and risk of autistic disorder using nationwide registry data on pairs of singleton full siblings born in Norway. We defined interpregnancy interval as the time from birth of the first-born child to conception of the second-born child in a sibship. The outcome of interest was autistic disorder in the second-born child. Analyses were restricted to sibships in which the second-born child was born in 1990-2004. Odds ratios (ORs) were estimated by fitting ordinary logistic models and logistic generalized additive models. The study sample included 223,476 singleton full-sibling pairs. In sibships with interpregnancy intervals <9 months, 0.25% of the second-born children had autistic disorder, compared with 0.13% in the reference category (≥ 36 months). For interpregnancy intervals shorter than 9 months, the adjusted OR of autistic disorder in the second-born child was 2.18 (95% confidence interval 1.42-3.26). The risk of autistic disorder in the second-born child was also increased for interpregnancy intervals of 9-11 months in the adjusted analysis (OR = 1.71 [95% CI = 1.07-2.64]). Consistent with a previous report from California, interpregnancy intervals shorter than 1 year were associated with increased risk of autistic disorder in the second-born child. A possible explanation is depletion of micronutrients in mothers with closely spaced pregnancies.

  10. Racial bias in pain perception and response: experimental examination of automatic and deliberate processes.

    PubMed

    Mathur, Vani A; Richeson, Jennifer A; Paice, Judith A; Muzyka, Michael; Chiao, Joan Y

    2014-05-01

    Racial disparities in pain treatment pose a significant public health and scientific problem. Prior studies have demonstrated that clinicians and nonclinicians are less perceptive of, and suggest less treatment for, the pain of African Americans relative to European Americans. Here we investigate the effects of explicit/implicit patient race presentation, patient race, and perceiver race on pain perception and response. African American and European American participants rated pain perception, empathy, helping motivation, and treatment suggestion in response to vignettes about patients' pain. Vignettes were accompanied by a rapid (implicit) or static (explicit) presentation of an African or European American patient's face. Participants perceived and responded more to European American patients in the implicit prime condition, when the effect of patient race was below the level of conscious regulation. This effect was reversed when patient race was presented explicitly. Additionally, female participants perceived and responded more to the pain of all patients, relative to male participants, and in the implicit prime condition, African American participants were more perceptive and responsive than European Americans to the pain of all patients. Taken together, these results suggest that known disparities in pain treatment may be largely due to automatic (below the level of conscious regulation) rather than deliberate (subject to conscious regulation) biases. These biases were not associated with traditional implicit measures of racial attitudes, suggesting that biases in pain perception and response may be independent of general prejudice. Results suggest that racial biases in pain perception and treatment are at least partially due to automatic processes. When the relevance of patient race is made explicit, however, biases are attenuated and even reversed. We also find preliminary evidence that African Americans may be more sensitive to the pain of others than are European Americans. Copyright © 2014 American Pain Society. Published by Elsevier Inc. All rights reserved.

  11. Adaptive Numerical Algorithms in Space Weather Modeling

    NASA Technical Reports Server (NTRS)

    Toth, Gabor; vanderHolst, Bart; Sokolov, Igor V.; DeZeeuw, Darren; Gombosi, Tamas I.; Fang, Fang; Manchester, Ward B.; Meng, Xing; Nakib, Dalal; Powell, Kenneth G.; hide

    2010-01-01

    Space weather describes the various processes in the Sun-Earth system that present danger to human health and technology. The goal of space weather forecasting is to provide an opportunity to mitigate these negative effects. Physics-based space weather modeling is characterized by disparate temporal and spatial scales as well as by different physics in different domains. A multi-physics system can be modeled by a software framework comprising of several components. Each component corresponds to a physics domain, and each component is represented by one or more numerical models. The publicly available Space Weather Modeling Framework (SWMF) can execute and couple together several components distributed over a parallel machine in a flexible and efficient manner. The framework also allows resolving disparate spatial and temporal scales with independent spatial and temporal discretizations in the various models. Several of the computationally most expensive domains of the framework are modeled by the Block-Adaptive Tree Solar wind Roe Upwind Scheme (BATS-R-US) code that can solve various forms of the magnetohydrodynamics (MHD) equations, including Hall, semi-relativistic, multi-species and multi-fluid MHD, anisotropic pressure, radiative transport and heat conduction. Modeling disparate scales within BATS-R-US is achieved by a block-adaptive mesh both in Cartesian and generalized coordinates. Most recently we have created a new core for BATS-R-US: the Block-Adaptive Tree Library (BATL) that provides a general toolkit for creating, load balancing and message passing in a 1, 2 or 3 dimensional block-adaptive grid. We describe the algorithms of BATL and demonstrate its efficiency and scaling properties for various problems. BATS-R-US uses several time-integration schemes to address multiple time-scales: explicit time stepping with fixed or local time steps, partially steady-state evolution, point-implicit, semi-implicit, explicit/implicit, and fully implicit numerical schemes. Depending on the application, we find that different time stepping methods are optimal. Several of the time integration schemes exploit the block-based granularity of the grid structure. The framework and the adaptive algorithms enable physics based space weather modeling and even forecasting.

  12. Endocrine and aggressive responses to competition are moderated by contest outcome, gender, individual versus team competition, and implicit motives

    PubMed Central

    Oxford, Jon K.; Tiedtke, Johanna M.; Ossmann, Anna; Özbe, Dominik

    2017-01-01

    This study examined hormonal responses to competition in relation to gender, social context, and implicit motives. Participants (N = 326) were randomly assigned to win or lose in a 10-round, virtual face-to-face competition, in same-sex individual- and team-competition contexts. Saliva samples, taken before and twice after the competition, were assayed for testosterone (T), estradiol (E), progesterone (P), and cortisol (C). Implicit needs for power (nPower) and affiliation (nAffiliation) were assessed with a picture-story exercise before the competition. Aggression was measured via the volume at which participants set noise blasts for their opponents. Men competing individually and women competing as teams showed similar T increases after winning. C was differentially associated with outcome in the team matches, with higher post-match cortisol for winning women, and an opposite effect for male teams. Analyses including implicit motives indicated that situational variables interacted with motivational needs in shaping hormonal responses to competition: in naturally cycling women, nPower predicted T increases after winning and T and E decreases after losing. In men, nPower predicted T increases after losing and decreases after winning. In male teams, nPower predicted C increases after losing, but not after winning, whereas in individual competitions, nPower was a general negative predictor of C changes in women. nAffiliation predicted P increases for women competing as teams, and P decreases for women competing individually. Aggression was higher in men, losers, and teams than in women, winners, and individuals. High aggression was associated with high baseline C in women competing individually and with low baseline C and C decreases in women competing as teams and in men generally. Our findings suggest that while situational and gender factors play a role in hormonal responses to competition, they also depend on their interplay with motivational factors. They also suggest that while aggression is strongly affected by situational factors in the context of a competition, it has no direct association with motivational and hormonal correlates of dominance (nPower, T, E) and instead is associated with (mostly) low levels of C. PMID:28750061

  13. Distinguishing the affective and cognitive bases of implicit attitudes to improve prediction of food choices.

    PubMed

    Trendel, Olivier; Werle, Carolina O C

    2016-09-01

    Eating behaviors largely result from automatic processes. Yet, in existing research, automatic or implicit attitudes toward food often fail to predict eating behaviors. Applying findings in cognitive neuroscience research, we propose and find that a central reason why implicit attitudes toward food are not good predictors of eating behaviors is that implicit attitudes are driven by two distinct constructs that often have diverging evaluative consequences: the automatic affective reactions to food (e.g., tastiness; the affective basis of implicit attitudes) and the automatic cognitive reactions to food (e.g., healthiness; the cognitive basis of implicit attitudes). More importantly, we find that the affective and cognitive bases of implicit attitudes directly and uniquely influence actual food choices under different conditions. While the affective basis of implicit attitude is the main driver of food choices, it is the only driver when cognitive resources during choice are limited. The cognitive basis of implicit attitudes uniquely influences food choices when cognitive resources during choice are plentiful but only for participants low in impulsivity. Researchers interested in automatic processes in eating behaviors could thus benefit by distinguishing between the affective and cognitive bases of implicit attitudes. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Healthy(?), wealthy, and wise: Birth order and adult health.

    PubMed

    Black, Sandra E; Devereux, Paul J; Salvanes, Kjell G

    2016-12-01

    While recent research has found that birth order affects outcomes such as education and earnings, the evidence for effects on health is more limited. This paper uses a large Norwegian dataset to focus on the relationship between birth order and a range of health and health-related behaviors, outcomes not previously available in datasets of this magnitude. Interestingly, we find complicated effects of birth order. First-borns are more likely to be overweight, to be obese, and to have high blood pressure and high triglycerides. For example, compared to fifth-borns, first-borns are about 5% points more likely to be obese and 7% points more likely to have high blood pressure. So, unlike education or earnings, there is no clear first-born advantage in health. However, first-borns are about 13% points less likely to smoke daily than fifth-borns and are more likely to report good physical and mental health. Later-borns also score lower on well-being with fifth-borns being about 9% points less likely than first-borns to report that they are happy. Our findings are generally monotonic with middle-borns having outcomes that are intermediate between first- and fifth-borns. We find that these effects are largely unaffected by conditioning on education and earnings, suggesting that these are not the only important pathways to health differentials by birth order. When we explore possible mechanisms, we find that early maternal investment may play a role in birth order effects on health. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. The Latino Paradox in Neighborhood Context: The Case of Asthma and Other Respiratory Conditions

    PubMed Central

    Cagney, Kathleen A.; Browning, Christopher R.; Wallace, Danielle M.

    2007-01-01

    Objectives. Evidence indicates that foreign-born Latinos have a health advantage compared with US-born persons of the same socioeconomic status. An explanation for this paradox has remained elusive. We examined the extent to which this paradox exists for the prevalence of asthma and other respiratory conditions. We then explored the role of neighborhood social context in understanding any observed advantage. We invoked theories of social organization, collective efficacy, and the urban ethnic enclave. Methods. We combined data from the Project on Human Development in Chicago Neighborhoods Community Survey with 2 other data sources and used hierarchical generalized linear modeling techniques. Results. We found a distinctly graded effect for asthma and other breathing problems among foreign-born Latinos, depending on community composition. Foreign-born Latinos embedded in a neighborhood that had a high percentage of foreign-born residents experienced a significantly lower prevalence of asthma and other breathing problems; those in communities that had a low percentage of foreign-born residents had the highest prevalence overall (even when compared with African Americans). Conclusions. Foreign-born Latinos have a respiratory health advantage only in enclave-like settings. Contexts such as these may provide the cohesiveness critical for effective prevention. PMID:17395846

  16. Prostate and Colorectal Cancer Screening Uptake among US and Foreign-Born Males: Evidence from the 2015 NHIS Survey.

    PubMed

    Ilunga Tshiswaka, Daudet; Donley, Tiffany; Okafor, Anthony; Memiah, Peter; Mbizo, Justice

    2017-06-01

    Research suggests that prostate and colorectal cancers disproportionately affect men in the US, but little is known about the determinants of prostate-specific antigen (PSA) and colorectal cancer (CRC) screening uptake among US and foreign-born males. The purpose of this study was to investigate what factors influence prostate and colorectal cancer screening uptake among US-native born and foreign-born men. Using the 2015 National Health Interview Survey, we conducted bivariate and multivariate analyses to highlight factors associated with the uptake of prostate and colorectal cancer screening among US-native born and foreign-born men. The sample size consisted of 5651 men respondents, with the mean age of 59.7 years (SD = 12.1). Of these, more than two-fifths (42%) were aged 50-64 years old. With respect to race/ethnicity, the sample was predominantly non-Hispanic Whites (65.5%), 863 (15.6%) Hispanics, and 710 (12.4%) Blacks. Our analysis found higher rates of both US-born and foreign-born men aged 65 years or older, who had either a PSA or CRC screening tests than those aged <65 years. Results of the general multivariate model suggest that men under 50 years old, US-born and foreign-born alike, are statistically significantly less likely to have prostate or colorectal cancer screenings than men aged 65 years or above. This study highlights the influencing factors that encourage or discourage PSA and CRC screening uptake between US-native born and foreign-born men. The results of this inquiry provide an evidence-based blueprint for policymakers and interventionists seeking to address prostate and colorectal cancer among men.

  17. Spacecraft-borne long life cryogenic refrigeration: Status and trends

    NASA Technical Reports Server (NTRS)

    Johnson, A. L.

    1983-01-01

    The status of cryogenic refrigerator development intended for, or possibly applicable to, long life spacecraft-borne application is reviewed. Based on these efforts, the general development trends are identified. Using currently projected technology needs, the various trends are compared and evaluated. The linear drive, non-contacting bearing Stirling cycle refrigerator concept appears to be the best current approach that will meet the technology projection requirements for spacecraft-borne cryogenic refrigerators. However, a multiply redundant set of lightweight, moderate life, moderate reliability Stirling cycle cryogenic refrigerators using high-speed linear drive and sliding contact bearings may possibly suffice.

  18. Using implicit association tests for the assessment of implicit personality self-concepts of extraversion and neuroticism in schizophrenia.

    PubMed

    Suslow, Thomas; Lindner, Christian; Kugel, Harald; Egloff, Boris; Schmukle, Stefan C

    2014-08-30

    There is evidence from research based on self-report personality measures that schizophrenia patients tend to be lower in extraversion and higher in neuroticism than healthy individuals. Self-report personality measures assess aspects of the explicit self-concept. The Implicit Association Test (IAT) has been developed to assess aspects of implicit cognition such as implicit attitudes and implicit personality traits. The present study was conducted to investigate the applicability and reliability of the IAT in schizophrenia patients and test whether they differ from healthy individuals on implicitly measured extraversion and neuroticism. The IAT and the NEO-FFI were administered as implicit and explicit measures of extraversion and neuroticism to 34 schizophrenia patients and 45 healthy subjects. For all IAT scores satisfactory to good reliabilities were observed in the patient sample. In both study groups, IAT scores were not related to NEO-FFI scores. Schizophrenia patients were lower in implicit and explicit extraversion and higher in implicit and explicit neuroticism than healthy individuals. Our data show that the IAT can be reliably applied to schizophrenia patients and suggest that they differ from healthy individuals not only in their conscious representation but also in their implicit representation of the self with regard to neuroticism and extraversion-related characteristics. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Implicit Associations and Explicit Expectancies toward Cannabis in Heavy Cannabis Users and Controls

    PubMed Central

    Beraha, Esther M.; Cousijn, Janna; Hermanides, Elisa; Goudriaan, Anna E.; Wiers, Reinout W.

    2013-01-01

    Cognitive biases, including implicit memory associations are thought to play an important role in the development of addictive behaviors. The aim of the present study was to investigate implicit affective memory associations in heavy cannabis users. Implicit positive-arousal, sedation, and negative associations toward cannabis were measured with three Single Category Implicit Association Tests (SC-IAT’s) and compared between 59 heavy cannabis users and 89 controls. Moreover, we investigated the relationship between these implicit affective associations and explicit expectancies, subjective craving, cannabis use, and cannabis related problems. Results show that heavy cannabis users had stronger implicit positive-arousal associations but weaker implicit negative associations toward cannabis compared to controls. Moreover, heavy cannabis users had stronger sedation but weaker negative explicit expectancies toward cannabis compared to controls. Within heavy cannabis users, more cannabis use was associated with stronger implicit negative associations whereas more cannabis use related problems was associated with stronger explicit negative expectancies, decreasing the overall difference on negative associations between cannabis users and controls. No other associations were observed between implicit associations, explicit expectancies, measures of cannabis use, cannabis use related problems, or subjective craving. These findings indicate that, in contrast to other substances of abuse like alcohol and tobacco, the relationship between implicit associations and cannabis use appears to be weak in heavy cannabis users. PMID:23801968

  20. Implicit and explicit ethnocentrism: revisiting the ideologies of prejudice.

    PubMed

    Cunningham, William A; Nezlek, John B; Banaji, Mahzarin R

    2004-10-01

    Two studies investigated relationships among individual differences in implicit and explicit prejudice, right-wing ideology, and rigidity in thinking. The first study examined these relationships focusing on White Americans' prejudice toward Black Americans. The second study provided the first test of implicit ethnocentrism and its relationship to explicit ethnocentrism by studying the relationship between attitudes toward five social groups. Factor analyses found support for both implicit and explicit ethnocentrism. In both studies, mean explicit attitudes toward out groups were positive, whereas implicit attitudes were negative, suggesting that implicit and explicit prejudices are distinct; however, in both studies, implicit and explicit attitudes were related (r = .37, .47). Latent variable modeling indicates a simple structure within this ethnocentric system, with variables organized in order of specificity. These results lead to the conclusion that (a) implicit ethnocentrism exists and (b) it is related to and distinct from explicit ethnocentrism.

  1. Gambling and Sport: Implicit Association and Explicit Intention Among Underage Youth.

    PubMed

    Li, En; Langham, Erika; Browne, Matthew; Rockloff, Matthew; Thorne, Hannah

    2018-03-23

    This study examined whether an implicit association existed between gambling and sport among underage youth in Australia, and whether this implicit association could shape their explicit intention to gamble. A sample of 14-17 year old Australian participants completed two phases of tasks, including an implicit association test based online experiment, and a post-experiment online survey. The results supported the existence of an implicit association between gambling and sport among the participants. This implicit association became stronger when they saw sport-relevant (vs. sport-irrelevant) gambling logos, or gambling-relevant (vs. gambling-irrelevant) sport names. In addition, this implicit association was positively related to the amount of sport viewing, but only among those participants who had more favorable gambling attitudes. Lastly, gambling attitudes and advertising knowledge, rather than the implicit association, turned out to be significant predictors of the explicit intention to gamble.

  2. Hooked on a feeling: affective anti-smoking messages are more effective than cognitive messages at changing implicit evaluations of smoking

    PubMed Central

    Smith, Colin Tucker; De Houwer, Jan

    2015-01-01

    Because implicit evaluations are thought to underlie many aspects of behavior, researchers have started looking for ways to change them. We examine whether and when persuasive messages alter strongly held implicit evaluations of smoking. In smokers, an affective anti-smoking message led to more negative implicit evaluations on four different implicit measures as compared to a cognitive anti-smoking message which seemed to backfire. Additional analyses suggested that the observed effects were mediated by the feelings and emotions raised by the messages. In non-smokers, both the affective and cognitive message engendered slightly more negative implicit evaluations. We conclude that persuasive messages change implicit evaluations in a way that depends on properties of the message and of the participant. Thus, our data open new avenues for research directed at tailoring persuasive messages to change implicit evaluations. PMID:26557099

  3. Hooked on a feeling: affective anti-smoking messages are more effective than cognitive messages at changing implicit evaluations of smoking.

    PubMed

    Smith, Colin Tucker; De Houwer, Jan

    2015-01-01

    Because implicit evaluations are thought to underlie many aspects of behavior, researchers have started looking for ways to change them. We examine whether and when persuasive messages alter strongly held implicit evaluations of smoking. In smokers, an affective anti-smoking message led to more negative implicit evaluations on four different implicit measures as compared to a cognitive anti-smoking message which seemed to backfire. Additional analyses suggested that the observed effects were mediated by the feelings and emotions raised by the messages. In non-smokers, both the affective and cognitive message engendered slightly more negative implicit evaluations. We conclude that persuasive messages change implicit evaluations in a way that depends on properties of the message and of the participant. Thus, our data open new avenues for research directed at tailoring persuasive messages to change implicit evaluations.

  4. Adults' implicit associations to infant positive and negative acoustic cues: Moderation by empathy and gender.

    PubMed

    Senese, Vincenzo Paolo; Venuti, Paola; Giordano, Francesca; Napolitano, Maria; Esposito, Gianluca; Bornstein, Marc H

    2017-09-01

    In this study a novel auditory version of the Single Category Implicit Association Test (SC-IAT-A) was developed to investigate (a) the valence of adults' associations to infant cries and laughs, (b) moderation of implicit associations by gender and empathy, and (c) the robustness of implicit associations controlling for auditory sensitivity. Eighty adults (50% females) were administered two SC-IAT-As, the Empathy Quotient, and the Weinstein Noise Sensitivity Scale. Adults showed positive implicit associations to infant laugh and negative ones to infant cry; only the implicit associations with the infant laugh were negatively related to empathy scores, and no gender differences were observed. Finally, implicit associations to infant cry were affected by noise sensitivity. The SC-IAT-A is useful to evaluate the valence of implicit reactions to infant auditory cues and could provide fresh insights into understanding processes that regulate the quality of adult-infant relationships.

  5. Self-Regulation and Implicit Attitudes Toward Physical Activity Influence Exercise Behavior.

    PubMed

    Padin, Avelina C; Emery, Charles F; Vasey, Michael; Kiecolt-Glaser, Janice K

    2017-08-01

    Dual-process models of health behavior posit that implicit and explicit attitudes independently drive healthy behaviors. Prior evidence indicates that implicit attitudes may be related to weekly physical activity (PA) levels, but the extent to which self-regulation attenuates this link remains unknown. This study examined the associations between implicit attitudes and self-reported PA during leisure time among 150 highly active young adults and evaluated the extent to which effortful control (one aspect of self-regulation) moderated this relationship. Results indicated that implicit attitudes toward exercise were unrelated to average workout length among individuals with higher effortful control. However, those with lower effortful control and more negative implicit attitudes reported shorter average exercise sessions compared with those with more positive attitudes. Implicit and explicit attitudes were unrelated to total weekly PA. A combination of poorer self-regulation and negative implicit attitudes may leave individuals vulnerable to mental and physical health consequences of low PA.

  6. Using the Implicit Association Test and the Implicit Relational Assessment Procedure to Measure Attitudes toward Meat and Vegetables in Vegetarians and Meat-Eaters

    ERIC Educational Resources Information Center

    Barnes-Holmes, Dermot; Murtagh, Louise; Barnes-Holmes, Yvonne; Stewart, Ian

    2010-01-01

    The current study aimed to assess the implicit attitudes of vegetarians and non-vegetarians towards meat and vegetables, using the Implicit Association Test (IAT) and the Implicit Relational Assessment Procedure (IRAP). Both measures involved asking participants to respond, under time pressure, to pictures of meat or vegetables as either positive…

  7. Medical student, nursing student, and non-health care respondents' implicit attitudes toward doctors and patients: Development and a pilot study of a new implicit attitudes test (IAT).

    PubMed

    Schwartz, Alan; Mazouni, Abdelhamid

    2017-01-01

    Medical educators have been concerned that medical students may decline in empathy for patients during the course of their training, based on studies measuring clinical empathy using psychometrically strong self-report measures. Clinical empathy is a complex construct, incorporating attitudes toward patients but also other components, such as professional detachment. Triangulation of extant measures with instruments based on nonreactive methods could provide a better understanding of whether and how physician attitudes toward patients may be changing during training. We sought to develop and pilot-test such a nonreactive method. We develop variations of an implicit association test (IAT) designed to measure attitudes toward physicians and patients based on speed of reaction to images of actors and positive and negative words. In the IATs, the same actors are photographed as doctors, clinic outpatients, hospitalized inpatients, and as a "general public" control. We examine preliminary evidence for their validity by collecting pilot data from internet participants (not involved in the health professions), medical students, and nursing students. Internet participants (n = 314) and nursing students (n = 31) had more negative associations (IAT scores) with doctors than did medical students (n = 89); nursing students and female internet participants had more positive associations with hospitalized patients than did medical students and male internet participants. Medical students' associations with hospitalized patients varied by year of training. This IAT may provide insight into implicit attitudes among those who enter training for the health profession and changes in those attitudes that may be inculcated during that training.

  8. Perceptual training methods compared: the relative efficacy of different approaches to enhancing sport-specific anticipation.

    PubMed

    Abernethy, Bruce; Schorer, Jörg; Jackson, Robin C; Hagemann, Norbert

    2012-06-01

    The comparative efficacy of different perceptual training approaches for the improvement of anticipation was examined using a goalkeeping task from European handball that required the rapid prediction of shot direction. Novice participants (N = 60) were assigned equally to four different training groups and two different control groups (a placebo group and a group who undertook no training). The training groups received either (i) explicit rules to guide anticipation; (ii) direction as to the location of the key anticipatory cues provided either just verbally (verbal cueing) or supplemented with color highlighting (color cueing); or (iii) undertook a matching judgment task to encourage implicit learning. Performance of the groups was compared on an anticipation test administered before training, after the training intervention, under a condition involving evaluative stress, and after a 5-month retention period. The explicit learning, verbal cueing, and implicit learning conditions provided the greatest sustained improvements in performance whereas the group given color cueing performed no better than the control groups. Only the implicit learning group showed performance superior to the control groups under the stress situation. The verbal cueing, color cueing, and implicit learning groups formulated the lowest number of explicit rules related to the critical shoulder cue although the reported use of general cues and rules based on all cues did not differ between any of the groups. Anticipation can be improved through a variety of different perceptual training approaches with the relative efficacy of the different approaches being contingent upon both the time scale and conditions under which learning is assessed.

  9. Discrimination, Racial Bias, and Telomere Length in African-American Men

    PubMed Central

    Chae, David H.; Nuru-Jeter, Amani M.; Adler, Nancy E.; Brody, Gene H.; Lin, Jue; Blackburn, Elizabeth H.; Epel, Elissa S.

    2013-01-01

    Background Leukocyte telomere length (LTL) is an indicator of general systemic aging, with shorter LTL being associated with several chronic diseases of aging and earlier mortality. Identifying factors related to LTL among African Americans may yield insights into mechanisms underlying racial disparities in health. Purpose To test whether the combination of more frequent reports of racial discrimination and holding a greater implicit anti-black racial bias is associated with shorter LTL among African-American men. Methods Cross-sectional study of a community sample of 92 African-American men aged between 30 and 50 years. Participants were recruited from February to May 2010. Ordinary least squares regressions were used to examine LTL in kilobase pairs in relation to racial discrimination and implicit racial bias. Data analysis was completed in July 2013. Results After controlling for chronologic age, socioeconomic, and health-related characteristics, the interaction between racial discrimination and implicit racial bias was significantly associated with LTL (b= −0.10, SE=0.04, p=0.02). Those demonstrating a stronger implicit anti-black bias and reporting higher levels of racial discrimination had the shortest LTL. Household income-to-poverty threshold ratio was also associated with LTL (b=0.05, SE=0.02, p<0.01). Conclusions Results suggest that multiple levels of racism, including interpersonal experiences of racial discrimination and the internalization of negative racial bias, operate jointly to accelerate biological aging among African-American men. Societal efforts to address racial discrimination in concert with efforts to promote positive in-group racial attitudes may protect against premature biological aging in this population. PMID:24439343

  10. Target size matters: target errors contribute to the generalization of implicit visuomotor learning.

    PubMed

    Reichenthal, Maayan; Avraham, Guy; Karniel, Amir; Shmuelof, Lior

    2016-08-01

    The process of sensorimotor adaptation is considered to be driven by errors. While sensory prediction errors, defined as the difference between the planned and the actual movement of the cursor, drive implicit learning processes, target errors (e.g., the distance of the cursor from the target) are thought to drive explicit learning mechanisms. This distinction was mainly studied in the context of arm reaching tasks where the position and the size of the target were constant. We hypothesize that in a dynamic reaching environment, where subjects have to hit moving targets and the targets' dynamic characteristics affect task success, implicit processes will benefit from target errors as well. We examine the effect of target errors on learning of an unnoticed perturbation during unconstrained reaching movements. Subjects played a Pong game, in which they had to hit a moving ball by moving a paddle controlled by their hand. During the game, the movement of the paddle was gradually rotated with respect to the hand, reaching a final rotation of 25°. Subjects were assigned to one of two groups: The high-target error group played the Pong with a small ball, and the low-target error group played with a big ball. Before and after the Pong game, subjects performed open-loop reaching movements toward static targets with no visual feedback. While both groups adapted to the rotation, the postrotation reaching movements were directionally biased only in the small-ball group. This result provides evidence that implicit adaptation is sensitive to target errors. Copyright © 2016 the American Physiological Society.

  11. [Analysis of implicit memory during propofol anesthesia].

    PubMed

    Biescas Prat, J; Moix Queraltó, J; Casanovas Catot, P

    2000-12-01

    Consensus has not been achieved on the presence of unconscious memory of messages in general anesthesia for methodological reasons. Our objective was to apply a model of anesthesia that allows for clinical control of the level of hypnosis in order to evaluate the presence and characteristics of implicit memory in deep sedation with propofol. We randomly assigned 48 consecutive patients undergoing lower limb surgery to two groups. In both groups subarachnoid anesthesia was with varying doses of propofol to maintain a level of hypnosis marked by inability to respond to orders, absence of movements and spontaneous ventilation. The experimental group listened to a recording of the words "banana" and "melon" for the semantic category of fruits and "white" and "black" for colors. The control group listened to a recording of environmental operating room noise. We recorded, among other variables, anxiety and age. Upon awakening, after the presence of conscious memory had been ruled out, we investigated implicit memory by comparing the percentage of correct answers in the two groups. The experimental group had a higher percentage of correct fruit names (p = 0.03). No differences were detected for colors. The youngest patients in the experimental group were correct more often about the fruits than were older members (p = 0.04) and those with greater anxiety were more often correct (p = 0.002). Implicit memory is preserved under hypnosis with propofol and is more likely to be present among those who are younger or experience greater anxiety. Concrete words with object references are more easily remembered than abstract words referring to perception. The semantic load of messages is relevant.

  12. Explicit and implicit springback simulation in sheet metal forming using fully coupled ductile damage and distortional hardening model

    NASA Astrophysics Data System (ADS)

    Yetna n'jock, M.; Houssem, B.; Labergere, C.; Saanouni, K.; Zhenming, Y.

    2018-05-01

    The springback is an important phenomenon which accompanies the forming of metallic sheets especially for high strength materials. A quantitative prediction of springback becomes very important for newly developed material with high mechanical characteristics. In this work, a numerical methodology is developed to quantify this undesirable phenomenon. This methodoly is based on the use of both explicit and implicit finite element solvers of Abaqus®. The most important ingredient of this methodology consists on the use of highly predictive mechanical model. A thermodynamically-consistent, non-associative and fully anisotropic elastoplastic constitutive model strongly coupled with isotropic ductile damage and accounting for distortional hardening is then used. An algorithm for local integration of the complete set of the constitutive equations is developed. This algorithm considers the rotated frame formulation (RFF) to ensure the incremental objectivity of the model in the framework of finite strains. This algorithm is implemented in both explicit (Abaqus/Explicit®) and implicit (Abaqus/Standard®) solvers of Abaqus® through the users routine VUMAT and UMAT respectively. The implicit solver of Abaqus® has been used to study spingback as it is generally a quasi-static unloading. In order to compare the methods `efficiency, the explicit method (Dynamic Relaxation Method) proposed by Rayleigh has been also used for springback prediction. The results obtained within U draw/bending benchmark are studied, discussed and compared with experimental results as reference. Finally, the purpose of this work is to evaluate the reliability of different methods predict efficiently springback in sheet metal forming.

  13. Geometric multigrid for an implicit-time immersed boundary method

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

    Guy, Robert D.; Philip, Bobby; Griffith, Boyce E.

    2014-10-12

    The immersed boundary (IB) method is an approach to fluid-structure interaction that uses Lagrangian variables to describe the deformations and resulting forces of the structure and Eulerian variables to describe the motion and forces of the fluid. Explicit time stepping schemes for the IB method require solvers only for Eulerian equations, for which fast Cartesian grid solution methods are available. Such methods are relatively straightforward to develop and are widely used in practice but often require very small time steps to maintain stability. Implicit-time IB methods permit the stable use of large time steps, but efficient implementations of such methodsmore » require significantly more complex solvers that effectively treat both Lagrangian and Eulerian variables simultaneously. Moreover, several different approaches to solving the coupled Lagrangian-Eulerian equations have been proposed, but a complete understanding of this problem is still emerging. This paper presents a geometric multigrid method for an implicit-time discretization of the IB equations. This multigrid scheme uses a generalization of box relaxation that is shown to handle problems in which the physical stiffness of the structure is very large. Numerical examples are provided to illustrate the effectiveness and efficiency of the algorithms described herein. Finally, these tests show that using multigrid as a preconditioner for a Krylov method yields improvements in both robustness and efficiency as compared to using multigrid as a solver. They also demonstrate that with a time step 100–1000 times larger than that permitted by an explicit IB method, the multigrid-preconditioned implicit IB method is approximately 50–200 times more efficient than the explicit method.« less

  14. I trust it, but I don't know why: effects of implicit attitudes toward automation on trust in an automated system.

    PubMed

    Merritt, Stephanie M; Heimbaugh, Heather; LaChapell, Jennifer; Lee, Deborah

    2013-06-01

    This study is the first to examine the influence of implicit attitudes toward automation on users' trust in automation. Past empirical work has examined explicit (conscious) influences on user level of trust in automation but has not yet measured implicit influences. We examine concurrent effects of explicit propensity to trust machines and implicit attitudes toward automation on trust in an automated system. We examine differential impacts of each under varying automation performance conditions (clearly good, ambiguous, clearly poor). Participants completed both a self-report measure of propensity to trust and an Implicit Association Test measuring implicit attitude toward automation, then performed an X-ray screening task. Automation performance was manipulated within-subjects by varying the number and obviousness of errors. Explicit propensity to trust and implicit attitude toward automation did not significantly correlate. When the automation's performance was ambiguous, implicit attitude significantly affected automation trust, and its relationship with propensity to trust was additive: Increments in either were related to increases in trust. When errors were obvious, a significant interaction between the implicit and explicit measures was found, with those high in both having higher trust. Implicit attitudes have important implications for automation trust. Users may not be able to accurately report why they experience a given level of trust. To understand why users trust or fail to trust automation, measurements of implicit and explicit predictors may be necessary. Furthermore, implicit attitude toward automation might be used as a lever to effectively calibrate trust.

  15. Investigation of High School Students' Online Science Information Searching Performance: The Role of Implicit and Explicit Strategies

    ERIC Educational Resources Information Center

    Tsai, Meng-Jung; Hsu, Chung-Yuan; Tsai, Chin-Chung

    2012-01-01

    Due to a growing trend of exploring scientific knowledge on the Web, a number of studies have been conducted to highlight examination of students' online searching strategies. The investigation of online searching generally employs methods including a survey, interview, screen-capturing, or transactional logs. The present study firstly intended to…

  16. Reasoning about Benefits, Costs, and Risks of Chemical Substances: Mapping Different Levels of Sophistication

    ERIC Educational Resources Information Center

    Cullipher, S.; Sevian, H.; Talanquer, V.

    2015-01-01

    The ability to evaluate options and make informed decisions about problems in relevant contexts is a core competency in science education that requires the use of both domain-general and discipline-specific knowledge and reasoning strategies. In this study we investigated the implicit assumptions and modes of reasoning applied by individuals with…

  17. The Identification of Sexual and Violent Motivations in Men Who Assault Women: Implication for Treatment

    ERIC Educational Resources Information Center

    Beech, Anthony R.; Ward, Tony; Fisher, Dawn

    2006-01-01

    A qualitative analysis of interview data with 41 rapists determined that five implicit theories (ITs) underlie rapists' offense supportive beliefs/feelings/motives: (a) dangerous world (DW)--where men have feelings of generalized anger and/or resentment toward others; (b) women are dangerous--where men hold a set of attitudes that are hostile…

  18. The Dimensions of Reading Comprehension in Dutch Children: Is Differentiation by Text and Question Type Necessary?

    ERIC Educational Resources Information Center

    Muijselaar, Marloes M. L.; Swart, Nicole M.; Steenbeek-Planting, Esther G.; Droop, Mienke; Verhoeven, Ludo; de Jong, Peter F.

    2017-01-01

    Many recent studies have aimed to demonstrate that specific types of reading comprehension depend on different underlying cognitive abilities. In these studies, it is often implicitly assumed that reading comprehension is a multidimensional construct. The general aim of this study was to examine the dimensionality of a large pool of reading…

  19. Factor Structure, Stability, and Congruence in the Functional Movement Screen

    ERIC Educational Resources Information Center

    Kelleher, Leila K.; Beach, Tyson A. C.; Frost, David M.; Johnson, Andrew M.; Dickey, James P.

    2018-01-01

    The scoring scheme for the functional movement screen implicitly assumes that the factor structure is consistent, stable, and congruent across different populations. To determine if this is the case, we compared principal components analyses of three samples: a healthy, general population (n = 100), a group of varsity athletes (n = 101), and a…

  20. Psychometric Inferences from a Meta-Analysis of Reliability and Internal Consistency Coefficients

    ERIC Educational Resources Information Center

    Botella, Juan; Suero, Manuel; Gambara, Hilda

    2010-01-01

    A meta-analysis of the reliability of the scores from a specific test, also called reliability generalization, allows the quantitative synthesis of its properties from a set of studies. It is usually assumed that part of the variation in the reliability coefficients is due to some unknown and implicit mechanism that restricts and biases the…

  1. Contribution of Implicit Sequence Learning to Spoken Language Processing: Some Preliminary Findings with Hearing Adults

    ERIC Educational Resources Information Center

    Conway, Christopher M.; Karpicke, Jennifer; Pisoni, David B.

    2007-01-01

    Spoken language consists of a complex, sequentially arrayed signal that contains patterns that can be described in terms of statistical relations among language units. Previous research has suggested that a domain-general ability to learn structured sequential patterns may underlie language acquisition. To test this prediction, we examined the…

  2. General Studies Writing (GSW) Digital Communication at Bowling Green State University: To Web 2.0 or Not To Web 2.0?

    ERIC Educational Resources Information Center

    Mauk, Brianna

    2017-01-01

    First-year composition pedagogy and course communication (especially as implicitly endorsed by institutionally presented means) is often limiting in modes and modalities, which juxtaposes vibrant composing practices in the daily lives of students. Additionally, writing program requirements tend to value primarily alphabetic texts despite…

  3. Distribution of Benefits in Teacher Retirement Systems and Their Implications for Mobility

    ERIC Educational Resources Information Center

    Costrell, Robert M.; Podgursky, Michael

    2010-01-01

    While it is generally understood that defined benefit pension systems concentrate benefits on career teachers and impose costs on mobile teachers, there has been very little analysis of the magnitude of these effects. The authors develop a measure of implicit redistribution of pension wealth among teachers at varying ages of separation. Compared…

  4. The Role of Multiple-Group Measurement Invariance in Family Psychology Research

    ERIC Educational Resources Information Center

    Kern, Justin L.; McBride, Brent A.; Laxman, Daniel J.; Dyer, W. Justin; Santos, Rosa M.; Jeans, Laurie M.

    2016-01-01

    Measurement invariance (MI) is a property of measurement that is often implicitly assumed, but in many cases, not tested. When the assumption of MI is tested, it generally involves determining if the measurement holds longitudinally or cross-culturally. A growing literature shows that other groupings can, and should, be considered as well.…

  5. Alternative Factor Models and Heritability of the Short Leyton Obsessional Inventory--Children's Version

    ERIC Educational Resources Information Center

    Moore, Janette; Smith, Gillian W.; Shevlin, Mark; O'Neill, Francis A.

    2010-01-01

    An alternative models framework was used to test three confirmatory factor analytic models for the Short Leyton Obsessional Inventory-Children's Version (Short LOI-CV) in a general population sample of 517 young adolescent twins (11-16 years). A one-factor model as implicit in current classification systems of Obsessive-Compulsive Disorder (OCD),…

  6. Distribution of Benefits in Teacher Retirement Systems and Their Implications for Mobility. Conference Paper 2009-04

    ERIC Educational Resources Information Center

    Costrell, Robert; Podgursky, Michael

    2009-01-01

    While it is generally understood that defined benefit pension systems concentrate benefits on career teachers, and impose costs on mobile teachers, there has been very little analysis of the magnitude of these features and patterns of variation between states. The authors develop a measure of implicit redistribution of pension wealth among…

  7. Distribution of Benefits in Teacher Retirement Systems and Their Implications for Mobility. Working Paper 39

    ERIC Educational Resources Information Center

    Costrell, Robert M.; Podgursky, Michael

    2009-01-01

    While it is generally understood that defined benefit pension systems concentrate benefits on career teachers and impose costs on mobile teachers, there has been very little analysis of the magnitude of these effects. The authors develop a measure of implicit redistribution of pension wealth among teachers at varying ages of separation. Compared…

  8. Implicit Knowledge of General Upper Secondary School in a Bridge-Building Project

    ERIC Educational Resources Information Center

    Rasmussen, Annette; Andreasen, Karen

    2016-01-01

    Bridge-building activities are practiced widely in the education systems of Europe. They are meant to bridge transitions between lower and upper secondary school and form a mandatory part of the youth guidance system in Denmark. By giving pupils the opportunity to experience the different educational context of upper secondary school,…

  9. Using the Implicit Association Test to Assess Children's Implicit Attitudes toward Smoking.

    PubMed

    Andrews, Judy A; Hampson, Sarah E; Greenwald, Anthony G; Gordon, Judith; Widdop, Chris

    2010-09-01

    The development and psychometric properties of an Implicit Association Test (IAT) measuring implicit attitude toward smoking among fifth grade children were described. The IAT with "sweets" as the contrast category resulted in higher correlations with explicit attitudes than did the IAT with "healthy foods" as the contrast category. Children with family members who smoked (versus non-smoking) and children who were high in sensation seeking (versus low) had a significantly more favorable implicit attitude toward smoking. Further, implicit attitudes became less favorable after engaging in tobacco prevention activities targeting risk perceptions of addiction. Results support the reliability and validity of this version of the IAT and illustrate its usefulness in assessing young children's implicit attitude toward smoking.

  10. Using the Implicit Association Test to Assess Children's Implicit Attitudes toward Smoking

    PubMed Central

    Andrews, Judy A.; Hampson, Sarah E.; Greenwald, Anthony G.; Gordon, Judith; Widdop, Chris

    2009-01-01

    The development and psychometric properties of an Implicit Association Test (IAT) measuring implicit attitude toward smoking among fifth grade children were described. The IAT with “sweets” as the contrast category resulted in higher correlations with explicit attitudes than did the IAT with “healthy foods” as the contrast category. Children with family members who smoked (versus non-smoking) and children who were high in sensation seeking (versus low) had a significantly more favorable implicit attitude toward smoking. Further, implicit attitudes became less favorable after engaging in tobacco prevention activities targeting risk perceptions of addiction. Results support the reliability and validity of this version of the IAT and illustrate its usefulness in assessing young children's implicit attitude toward smoking. PMID:21566676

  11. Neonatal Outcomes Following Delivery in Water: Evaluation of Safety in a District General Hospital.

    PubMed

    Peacock, Phil J; Zengeya, Stanley T; Cochrane, Lesley; Sleath, Maxine

    2018-02-20

    Introduction Giving birth in water has increased in popularity over recent years, with potential benefits in terms of maternal comfort and decreased rates of instrumental delivery. Some concerns have been raised about possible adverse neonatal outcomes, including hypothermia and respiratory distress. There is not currently, however, a clear consensus in the literature. This study sought to assess the safety of delivering in water for low-risk vaginal deliveries in a District General Hospital in the United Kingdom. Methods Prospectively collected hospital data was obtained for all deliveries between 1 April 2014 and 31 March 2016 at the Great Western Hospital, Swindon. The dataset was limited to full-term babies born by unassisted vaginal delivery following spontaneous labour; 3507 babies were included in the analyses. Pre-specified outcomes included neonatal unit admission, Apgar scores, and temperature after delivery. Results During the two-year period studied, there were 592 waterbirths and 2915 non-waterbirths. There was no significant difference in rates of neonatal unit admission between waterbirths and non-waterbirths. One-minute Apgar scores were slightly higher among those born in water (P = 0.04); this difference attenuated by five minutes of age. There was no difference in temperature after delivery between the two groups. Conclusions An evaluation of safety in a District General Hospital has demonstrated similar postnatal outcomes among babies born in water, compared to those born on land. Further work examining longer-term outcomes would help assess whether this persists beyond the newborn period.

  12. Power effects on implicit prejudice and stereotyping: The role of intergroup face processing.

    PubMed

    Schmid, Petra C; Amodio, David M

    2017-04-01

    Power is thought to increase discrimination toward subordinate groups, yet its effect on different forms of implicit bias remains unclear. We tested whether power enhances implicit racial stereotyping, in addition to implicit prejudice (i.e., evaluative associations), and examined the effect of power on the automatic processing of faces during implicit tasks. Study 1 showed that manipulated high power increased both forms of implicit bias, relative to low power. Using a neural index of visual face processing (the N170 component of the ERP), Study 2 revealed that power affected the encoding of White ingroup vs. Black outgroup faces. Whereas high power increased the relative processing of outgroup faces during evaluative judgments in the prejudice task, it decreased the relative processing of outgroup faces during stereotype trait judgments. An indirect effect of power on implicit prejudice through enhanced processing of outgroup versus ingroup faces suggested a potential link between face processing and implicit bias. Together, these findings demonstrate that power can affect implicit prejudice and stereotyping as well as early processing of racial ingroup and outgroup faces.

  13. Implicit Attitudes toward the Self Over Time in Chinese Undergraduates

    PubMed Central

    Yang, Qing; Zhao, Yufang; Guan, Lili; Huang, Xiting

    2017-01-01

    Although the explicit attitudes of Chinese people toward the self over time are known (i.e., past = present < future), little is known about their implicit attitudes. Two studies were conducted to measure the implicit subjective temporal trajectory (STT) of Chinese undergraduates. Study 1 used a Go/No-go association task to measure participants’ implicit attitudes toward their past, present, and future selves. The obtained implicit STT was different from the explicit pattern found in former research. It showed that the future self was viewed to be identical to the present self and participants implicitly evaluated their present self as better than the past self. Since this comparison of the past and present selves suggested a cultural difference, we aimed to replicate this finding in Study 2. Using an implicit association test, we again found that the present self was more easily associated with positive valence than the past self. Overall, both studies reveal an implicitly inclining-flat STT (i.e., past < present = future) for Chinese undergraduates. Implications of this difference in explicit-implicit measures and the cultural differences of temporal self appraisals are discussed. PMID:29163291

  14. Implicit Motives and Men’s Perceived Constraint in Fatherhood

    PubMed Central

    Ruppen, Jessica; Waldvogel, Patricia; Ehlert, Ulrike

    2016-01-01

    Research shows that implicit motives influence social relationships. However, little is known about their role in fatherhood and, particularly, how men experience their paternal role. Therefore, this study examined the association of implicit motives and fathers’ perceived constraint due to fatherhood. Furthermore, we explored their relation to fathers’ life satisfaction. Participants were fathers with biological children (N = 276). They were asked to write picture stories, which were then coded for implicit affiliation and power motives. Perceived constraint and life satisfaction were assessed on a visual analog scale. A higher implicit need for affiliation was significantly associated with lower perceived constraint, whereas the implicit need for power had the opposite effect. Perceived constraint had a negative influence on life satisfaction. Structural equation modeling revealed significant indirect effects of implicit affiliation and power motives on life satisfaction mediated by perceived constraint. Our findings indicate that men with a higher implicit need for affiliation experience less constraint due to fatherhood, resulting in higher life satisfaction. The implicit need for power, however, results in more perceived constraint and is related to decreased life satisfaction. PMID:27933023

  15. Health Care Providers’ Implicit and Explicit Attitudes Toward Lesbian Women and Gay Men

    PubMed Central

    Riskind, Rachel G.; Nosek, Brian A.

    2015-01-01

    Objectives. We examined providers’ implicit and explicit attitudes toward lesbian and gay people by provider gender, sexual identity, and race/ethnicity. Methods. We examined attitudes toward heterosexual people versus lesbian and gay people in Implicit Association Test takers: 2338 medical doctors, 5379 nurses, 8531 mental health providers, 2735 other treatment providers, and 214 110 nonproviders in the United States and internationally between May 2006 and December 2012. We characterized the sample with descriptive statistics and calculated Cohen d, a standardized effect size measure, with 95% confidence intervals. Results. Among heterosexual providers, implicit preferences always favored heterosexual people over lesbian and gay people. Implicit preferences for heterosexual women were weaker than implicit preferences for heterosexual men. Heterosexual nurses held the strongest implicit preference for heterosexual men over gay men (Cohen d = 1.30; 95% confidence interval = 1.28, 1.32 among female nurses; Cohen d = 1.38; 95% confidence interval = 1.32, 1.44 among male nurses). Among all groups, explicit preferences for heterosexual versus lesbian and gay people were weaker than implicit preferences. Conclusions. Implicit preferences for heterosexual people versus lesbian and gay people are pervasive among heterosexual health care providers. Future research should investigate how implicit sexual prejudice affects care. PMID:26180976

  16. Implicit attitudes towards homosexuality: reliability, validity, and controllability of the IAT.

    PubMed

    Banse, R; Seise, J; Zerbes, N

    2001-01-01

    Two experiments were conducted to investigate the psychometric properties of an Implicit Association Test (IAT; Greenwald, McGhee, & Schwartz, 1998) that was adapted to measure implicit attitudes towards homosexuality. In a first experiment, the validity of the Homosexuality-IAT was tested using a known group approach. Implicit and explicit attitudes were assessed in heterosexual and homosexual men and women (N = 101). The results provided compelling evidence for the convergent and discriminant validity of the Homosexuality-IAT as a measure of implicit attitudes. No evidence was found for two alternative explanations of IAT effects (familiarity with stimulus material and stereotype knowledge). The internal consistency of IAT scores was satisfactory (alpha s > .80), but retest correlations were lower. In a second experiment (N = 79) it was shown that uninformed participants were able to fake positive explicit but not implicit attitudes. Discrepancies between implicit and explicit attitudes towards homosexuality could be partially accounted for by individual differences in the motivation to control prejudiced behavior, thus providing independent evidence for the validity of the implicit attitude measure. Neither explicit nor implicit attitudes could be changed by persuasive messages. The results of both experiments are interpreted as evidence for a single construct account of implicit and explicit attitudes towards homosexuality.

  17. Effects of brief mindful acceptance induction on implicit dysfunctional attitudes and concordance between implicit and explicit dysfunctional attitudes.

    PubMed

    Keng, Shian-Ling; Seah, Stanley T H; Tong, Eddie M W; Smoski, Moria

    2016-08-01

    Mindfulness-based interventions have been shown to be effective in alleviating depressive symptoms. While much work has examined the effects of mindfulness training on subjective symptoms and experiences, and less is known regarding whether mindfulness training may alter relatively uncontrollable cognitive processes associated with depressed mood, particularly implicit dysfunctional attitudes. The present study examined the effects of a brief mindful acceptance induction on implicit dysfunctional attitudes and degree of concordance between implicit and explicit dysfunctional attitudes in the context of sad mood. A total of 79 adult participants with elevated depressive symptoms underwent an autobiographical mood induction procedure before being randomly assigned to mindful acceptance or thought wandering inductions. Results showed that the effect of mindful acceptance on implicit dysfunctional attitude was significantly moderated by trait mindfulness. Participants high on trait mindfulness demonstrated significant improvements in implicit dysfunctional attitudes following the mindful acceptance induction. Those low on trait mindfulness demonstrated significantly worse implicit dysfunctional attitudes following the induction. Significantly greater levels of concordance between implicit and explicit dysfunctional attitudes were observed in the mindful acceptance condition versus the thought wandering condition. The findings highlight changes in implicit dysfunctional attitudes and improvements in self-concordance as two potential mechanisms underlying the effects of mindfulness-based interventions. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Trends and solar cycle effects in mesospheric ice clouds

    NASA Astrophysics Data System (ADS)

    Lübken, Franz-Josef; Berger, Uwe; Fiedler, Jens; Baumgarten, Gerd; Gerding, Michael

    Lidar observations of mesospheric ice layers (noctilucent clouds, NLC) are now available since 12 years which allows to study solar cycle effects on NLC parameters such as altitudes, bright-ness, and occurrence rates. We present observations from our lidar stations in Kuehlungsborn (54N) and ALOMAR (69N). Different from general expectations the mean layer characteris-tics at ALOMAR do not show a persistent anti-correlation with solar cycle. Although a nice anti-correlation of Ly-alpha and occurrence rates is detected in the first half of the solar cycle, occurrence rates decreased with decreasing solar activity thereafter. Interestingly, in summer 2009 record high NLC parameters were detected as expected in solar minimum conditions. The morphology of NLC suggests that other processes except solar radiation may affect NLC. We have recently applied our LIMA model to study in detail the solar cycle effects on tempera-tures and water vapor concentration the middle atmosphere and its subsequent influence on mesospheric ice clouds. Furthermore, lower atmosphere effects are implicitly included because LIMA nudges to the conditions in the troposphere and lower stratosphere. We compare LIMA results regarding solar cycle effects on temperatures and ice layers with observations at ALO-MAR as well as satellite borne measurements. We will also present LIMA results regarding the latitude variation of solar cycle and trends, including a comparison of northern and southern hemisphere. We have adapted the observation conditions from SBUV (wavelength and scatter-ing angle) in LIMA for a detailed comparison with long term observations of ice clouds from satellites.

  19. Toward the accurate first-principles prediction of ionization equilibria in proteins.

    PubMed

    Khandogin, Jana; Brooks, Charles L

    2006-08-08

    The calculation of pK(a) values for ionizable sites in proteins has been traditionally based on numerical solutions of the Poisson-Boltzmann equation carried out using a high-resolution protein structure. In this paper, we present a method based on continuous constant pH molecular dynamics (CPHMD) simulations, which allows the first-principles description of protein ionization equilibria. Our method utilizes an improved generalized Born implicit solvent model with an approximate Debye-Hückel screening function to account for salt effects and the replica-exchange (REX) protocol for enhanced conformational and protonation state sampling. The accuracy and robustness of the present method are demonstrated by 1 ns REX-CPHMD titration simulations of 10 proteins, which exhibit anomalously large pK(a) shifts for the carboxylate and histidine side chains. The experimental pK(a) values of these proteins are reliably reproduced with a root-mean-square error ranging from 0.6 unit for proteins containing few buried ionizable side chains to 1.0 unit or slightly higher for proteins containing ionizable side chains deeply buried in the core and experiencing strong charge-charge interactions. This unprecedented level of agreement with experimental benchmarks for the de novo calculation of pK(a) values suggests that the CPHMD method is maturing into a practical tool for the quantitative prediction of protein ionization equilibria, and this, in turn, opens a door to atomistic simulations of a wide variety of pH-coupled conformational phenomena in biological macromolecules such as protein folding or misfolding, aggregation, ligand binding, membrane interaction, and catalysis.

  20. Parallel Tempering of Dark Matter from the Ebola Virus Proteome: Comparison of CHARMM36m and CHARMM22 Force Fields with Implicit Solvent.

    PubMed

    Olson, Mark A

    2018-01-22

    Intrinsically disordered proteins are characterized by their large manifold of thermally accessible conformations and their related statistical weights, making them an interesting target of simulation studies. To assess the development of a computational framework for modeling this distinct class of proteins, this work examines temperature-based replica-exchange simulations to generate a conformational ensemble of a 28-residue peptide from the Ebola virus protein VP35. Starting from a prefolded helix-β-turn-helix topology observed in a crystallographic assembly, the simulation strategy tested is the recently refined CHARMM36m force field combined with a generalized Born solvent model. A comparison of two replica-exchange methods is provided, where one is a traditional approach with a fixed set of temperatures and the other is an adaptive scheme in which the thermal windows are allowed to move in temperature space. The assessment is further extended to include a comparison with equivalent CHARMM22 simulation data sets. The analysis finds CHARMM36m to shift the minimum in the potential of mean force (PMF) to a lower fractional helicity compared with CHARMM22, while the latter showed greater conformational plasticity along the helix-forming reaction coordinate. Among the simulation models, only the adaptive tempering method with CHARMM36m found an ensemble of conformational heterogeneity consisting of transitions between α-helix-β-hairpin folds and unstructured states that produced a PMF of fractional fold propensity in qualitative agreement with circular dichroism experiments reporting a disordered peptide.

  1. All-atom ab initio native structure prediction of a mixed fold (1FME): A comparison of structural and folding characteristics of various ββα miniproteins

    NASA Astrophysics Data System (ADS)

    Kim, Eunae; Jang, Soonmin; Pak, Youngshang

    2009-11-01

    We performed an all-atom ab initio native structure prediction of 1FME, which is one of the computationally challenging mixed fold ββα miniproteins, by combining a novel conformational search algorithm (multiplexed Q-replica exchange molecular dynamics scheme) with a well-balanced all-atom force field employing a generalized Born implicit solvation model (param99MOD5/GBSA). The nativelike structure of 1FME was identified from the lowest free energy minimum state and in excellent agreement with the NMR structure. Based on the interpretation of the free energy landscape, the structural properties as well as the folding behaviors of 1FME were compared with other ββα miniproteins (1FSD, 1PSV, and BBA5) that we have previously studied with the same force field. Our simulation showed that the 28-residue ββα miniproteins (1FME, 1FSD, and 1PSV) share a common feature of the free energy topography and exhibit the three local minimum states on each computed free energy map, but the 23-residue miniprotein (BBA5) follows a downhill folding with a single minimum state. Also, the structure and stability changes resulting from the two point mutation (Gln1→Glu1 and Ile7→Tyr7) of 1FSD were investigated in details for direct comparison with the experiment. The comparison shows that upon mutation, the experimentally observed turn type switch from an irregular turn (1FSD) to type I' turn (1FME) was well reproduced with the present simulation.

  2. Spillover, nonlinearity, and flexible structures

    NASA Technical Reports Server (NTRS)

    Bass, Robert W.; Zes, Dean

    1991-01-01

    Many systems whose evolution in time is governed by Partial Differential Equations (PDEs) are linearized around a known equilibrium before Computer Aided Control Engineering (CACE) is considered. In this case, there are infinitely many independent vibrational modes, and it is intuitively evident on physical grounds that infinitely many actuators would be needed in order to control all modes. A more precise, general formulation of this grave difficulty (spillover problem) is due to A.V. Balakrishnan. A possible route to circumvention of this difficulty lies in leaving the PDE in its original nonlinear form, and adding the essentially finite dimensional control action prior to linearization. One possibly applicable technique is the Liapunov Schmidt rigorous reduction of singular infinite dimensional implicit function problems to finite dimensional implicit function problems. Omitting details of Banach space rigor, the formalities of this approach are given.

  3. Covert colour processing in colour agnosia.

    PubMed

    Nijboer, Tanja C W; van Zandvoort, Martine J E; de Haan, Edward H F

    2006-01-01

    Patients with colour agnosia can perceive colours and are able to match coloured patches on hue, but are unable to identify or categorise colours. It is a rare condition and there is as yet no agreement on the clinical definition or a generally accepted explanation. In line with observations from object agnosia and prosopagnosia, we hypothesised that (some of) these patients might still be able to process colour information at an implicit level. In this study, we investigated this possibility of implicit access to colour semantics and colour names in a man (MAH) who suffers from developmental colour agnosia. We designed two experimental computer tasks: an associative colour priming task with a lexical decision response and a reversed Stroop task. The results of these experiments suggest that there is indeed automatic processing of colour, although MAH was unable to explicitly use colour information.

  4. Punctuation and Implicit Prosody in Silent Reading: An ERP Study Investigating English Garden-Path Sentences.

    PubMed

    Drury, John E; Baum, Shari R; Valeriote, Hope; Steinhauer, Karsten

    2016-01-01

    This study presents the first two ERP reading studies of comma-induced effects of covert (implicit) prosody on syntactic parsing decisions in English. The first experiment used a balanced 2 × 2 design in which the presence/absence of commas determined plausibility (e.g., John, said Mary, was the nicest boy at the party vs. John said Mary was the nicest boy at the party ). The second reading experiment replicated a previous auditory study investigating the role of overt prosodic boundaries in closure ambiguities (Pauker et al., 2011). In both experiments, commas reliably elicited CPS components and generally played a dominant role in determining parsing decisions in the face of input ambiguity. The combined set of findings provides further evidence supporting the claim that mechanisms subserving speech processing play an active role during silent reading.

  5. Transnational surrogacy: Canada's contradictions.

    PubMed

    Lozanski, Kristin

    2015-01-01

    Transnational commercial surrogacy represents a form of medical tourism undertaken by intended parents who seek to hire women in other countries, increasingly often in the global South, as surrogates. While much of the scholarly literature focuses on the conditions of surrogacy within host countries, such as India, there has been limited analysis of transnational surrogacy focused upon origin countries. In this article, I build upon the scholarship that explores the impact of host country structures on transnational surrogacy, with special attention to the significance of Canadian citizenship policy through analysis of legislation and policy vis-à-vis transnational commercial surrogacy. The Canadian case demonstrates clear contradictions between the legislation and policy that is enacted domestically to prohibit commercial surrogacy within Canada and legislation and policy that implicitly sanctions commercial surrogacy through the straightforward provision of citizenship for children born of such arrangements abroad. The ethical underpinnings of Canada's domestic prohibition of commercial surrogacy, which is presumed to exploit women and children and to impede gender equality, are violated in Canada's bureaucratic willingness to accept children born of transnational commercial surrogacy as citizens. Thus, the ethical discourses apply only to Canadian citizens within Canadian geography. The failure of the Canadian government to hold Canadian citizens who participate in transnational commercial surrogacy to the normative imperatives that prohibit the practice within the country, or to undertake a more nuanced, and necessarily controversial, discussion of commercial surrogacy reinforces transnational disparities in terms of whose bodies may be commodified as a measure of gendered inequality. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Implicit-explicit (IMEX) Runge-Kutta methods for non-hydrostatic atmospheric models

    NASA Astrophysics Data System (ADS)

    Gardner, David J.; Guerra, Jorge E.; Hamon, François P.; Reynolds, Daniel R.; Ullrich, Paul A.; Woodward, Carol S.

    2018-04-01

    The efficient simulation of non-hydrostatic atmospheric dynamics requires time integration methods capable of overcoming the explicit stability constraints on time step size arising from acoustic waves. In this work, we investigate various implicit-explicit (IMEX) additive Runge-Kutta (ARK) methods for evolving acoustic waves implicitly to enable larger time step sizes in a global non-hydrostatic atmospheric model. The IMEX formulations considered include horizontally explicit - vertically implicit (HEVI) approaches as well as splittings that treat some horizontal dynamics implicitly. In each case, the impact of solving nonlinear systems in each implicit ARK stage in a linearly implicit fashion is also explored. The accuracy and efficiency of the IMEX splittings, ARK methods, and solver options are evaluated on a gravity wave and baroclinic wave test case. HEVI splittings that treat some vertical dynamics explicitly do not show a benefit in solution quality or run time over the most implicit HEVI formulation. While splittings that implicitly evolve some horizontal dynamics increase the maximum stable step size of a method, the gains are insufficient to overcome the additional cost of solving a globally coupled system. Solving implicit stage systems in a linearly implicit manner limits the solver cost but this is offset by a reduction in step size to achieve the desired accuracy for some methods. Overall, the third-order ARS343 and ARK324 methods performed the best, followed by the second-order ARS232 and ARK232 methods.

  7. Defensive function of persecutory delusion and discrepancy between explicit and implicit self-esteem in schizophrenia: study using the Brief Implicit Association Test

    PubMed Central

    Nakamura, Mitsuo; Hayakawa, Tomomi; Okamura, Aiko; Kohigashi, Mutsumi; Fukui, Kenji; Narumoto, Jin

    2015-01-01

    Background If delusions serve as a defense mechanism in schizophrenia patients with paranoia, then they should show normal or high explicit self-esteem and low implicit self-esteem. However, the results of previous studies are inconsistent. One possible explanation for this inconsistency is that there are two types of paranoia, “bad me” (self-blaming) paranoia and “poor me” (non-self-blaming) paranoia. We thus examined implicit and explicit self-esteem and self-blaming tendency in patients with schizophrenia and schizoaffective disorder. We hypothesized that patients with paranoia would show lower implicit self-esteem and only those with non-self-blaming paranoia would experience a discrepancy between explicit and implicit self-esteem. Methods Participants consisted of patients with schizophrenia and schizoaffective disorder recruited from a day hospital (N=71). Participants were assessed for psychotic symptoms, using the Brief Psychiatric Rating Scale (BPRS), and self-blaming tendency, using the brief COPE. We also assessed explicit self-esteem, using the Rosenberg Self-Esteem Scale (RSES), implicit self-esteem, using Brief Implicit Association Test (BIAT), and discrepancy between explicit and implicit self-esteem. Results Contrary to our hypothesis, implicit self-esteem in paranoia and nonparanoia showed no statistical difference. As expected, only patients with non-self-blaming paranoia experienced a discrepancy between explicit and implicit self-esteem; other groups showed no such discrepancy. Conclusion These results suggest that persecutory delusion plays a defensive role in non-self-blaming paranoia. PMID:25565849

  8. Increased congenital heart defects in children born to women with systemic lupus erythematosus: results from the offspring of Systemic Lupus Erythematosus Mothers Registry Study.

    PubMed

    Vinet, Évelyne; Pineau, Christian A; Scott, Susan; Clarke, Ann E; Platt, Robert W; Bernatsky, Sasha

    2015-01-13

    In a large population-based study, we aimed to determine whether children born to women with systemic lupus erythematosus (SLE) have an increased risk of congenital heart defects (CHDs) in comparison with children born to women without SLE. The Offspring of SLE Mothers Registry (OSLER) includes all women who had ≥1 hospitalization for delivery after SLE diagnosis, identified through Quebec's healthcare databases (1989-2009), and a randomly selected control group of women, matched ≥4:1 for age and year of delivery. We identified children born live to SLE mothers and their matched controls, and ascertained CHD based on ≥1 hospitalization or physician visit with relevant diagnostic codes, within the first 12 months of life. We performed multivariable logistic regression analyses, using the generalized estimating equation method, to adjust for relevant covariates. Five hundred nine women with SLE had 719 children, whereas 5824 matched controls had 8493 children. In comparison with controls, children born to women with SLE experienced more CHD (5.2% [95% confidence interval (CI), 3.7-7.1] versus 1.9% [95% CI, 1.6-2.2], difference 3.3% [95% CI, 1.9-5.2]). In multivariable analyses, children born to women with SLE had a substantially increased risk of CHD (odds ratio, 2.62; 95% CI, 1.77-3.88) in comparison with controls. In addition, in comparison with controls, offspring of SLE mothers had a substantially increased risk of having a CHD repair procedure (odds ratio, 5.82; 95% CI, 1.77-19.09). In comparison with children from the general population, children born to women with SLE have an increased risk of CHD, and an increased risk of having a CHD repair procedure, as well. © 2014 American Heart Association, Inc.

  9. Not explicit but implicit memory is influenced by individual perception style

    PubMed Central

    Tsushima, Yoshiaki

    2018-01-01

    Not only explicit but also implicit memory has considerable influence on our daily life. However, it is still unclear whether explicit and implicit memories are sensitive to individual differences. Here, we investigated how individual perception style (global or local) correlates with implicit and explicit memory. As a result, we found that not explicit but implicit memory was affected by the perception style: local perception style people more greatly used implicit memory than global perception style people. These results help us to make the new effective application adapting to individual perception style and understand some clinical symptoms such as autistic spectrum disorder. Furthermore, this finding might give us new insight of memory involving consciousness and unconsciousness as well as relationship between implicit/explicit memory and individual perception style. PMID:29370212

  10. Not explicit but implicit memory is influenced by individual perception style.

    PubMed

    Hine, Kyoko; Tsushima, Yoshiaki

    2018-01-01

    Not only explicit but also implicit memory has considerable influence on our daily life. However, it is still unclear whether explicit and implicit memories are sensitive to individual differences. Here, we investigated how individual perception style (global or local) correlates with implicit and explicit memory. As a result, we found that not explicit but implicit memory was affected by the perception style: local perception style people more greatly used implicit memory than global perception style people. These results help us to make the new effective application adapting to individual perception style and understand some clinical symptoms such as autistic spectrum disorder. Furthermore, this finding might give us new insight of memory involving consciousness and unconsciousness as well as relationship between implicit/explicit memory and individual perception style.

  11. [Effects of an implicit internal working model on attachment in information processing assessed using Go/No-Go Association Task].

    PubMed

    Fujii, Tsutomu; Uebuchi, Hisashi; Yamada, Kotono; Saito, Masahiro; Ito, Eriko; Tonegawa, Akiko; Uebuchi, Marie

    2015-06-01

    The purposes of the present study were (a) to use both a relational-anxiety Go/No-Go Association Task (GNAT) and an avoidance-of-intimacy GNAT in order to assess an implicit Internal Working Model (IWM) of attachment; (b) to verify the effects of both measured implicit relational anxiety and implicit avoidance of intimacy on information processing. The implicit IWM measured by GNAT differed from the explicit IWM measured by questionnaires in terms of the effects on information processing. In particular, in subliminal priming tasks involving with others, implicit avoidance of intimacy predicted accelerated response times with negative stimulus words about attachment. Moreover, after subliminally priming stimulus words about self, implicit relational anxiety predicted delayed response times with negative stimulus words about attachment.

  12. Automatic Evaluations and Exercising: Systematic Review and Implications for Future Research.

    PubMed

    Schinkoeth, Michaela; Antoniewicz, Franziska

    2017-01-01

    The general purpose of this systematic review was to summarize, structure and evaluate the findings on automatic evaluations of exercising. Studies were eligible for inclusion if they reported measuring automatic evaluations of exercising with an implicit measure and assessed some kind of exercise variable. Fourteen nonexperimental and six experimental studies (out of a total N = 1,928) were identified and rated by two independent reviewers. The main study characteristics were extracted and the grade of evidence for each study evaluated. First, results revealed a large heterogeneity in the applied measures to assess automatic evaluations of exercising and the exercise variables. Generally, small to large-sized significant relations between automatic evaluations of exercising and exercise variables were identified in the vast majority of studies. The review offers a systematization of the various examined exercise variables and prompts to differentiate more carefully between actually observed exercise behavior (proximal exercise indicator) and associated physiological or psychological variables (distal exercise indicator). Second, a lack of transparent reported reflections on the differing theoretical basis leading to the use of specific implicit measures was observed. Implicit measures should be applied purposefully, taking into consideration the individual advantages or disadvantages of the measures. Third, 12 studies were rated as providing first-grade evidence (lowest grade of evidence), five represent second-grade and three were rated as third-grade evidence. There is a dramatic lack of experimental studies, which are essential for illustrating the cause-effect relation between automatic evaluations of exercising and exercise and investigating under which conditions automatic evaluations of exercising influence behavior. Conclusions about the necessity of exercise interventions targeted at the alteration of automatic evaluations of exercising should therefore not be drawn too hastily.

  13. Automatic Evaluations and Exercising: Systematic Review and Implications for Future Research

    PubMed Central

    Schinkoeth, Michaela; Antoniewicz, Franziska

    2017-01-01

    The general purpose of this systematic review was to summarize, structure and evaluate the findings on automatic evaluations of exercising. Studies were eligible for inclusion if they reported measuring automatic evaluations of exercising with an implicit measure and assessed some kind of exercise variable. Fourteen nonexperimental and six experimental studies (out of a total N = 1,928) were identified and rated by two independent reviewers. The main study characteristics were extracted and the grade of evidence for each study evaluated. First, results revealed a large heterogeneity in the applied measures to assess automatic evaluations of exercising and the exercise variables. Generally, small to large-sized significant relations between automatic evaluations of exercising and exercise variables were identified in the vast majority of studies. The review offers a systematization of the various examined exercise variables and prompts to differentiate more carefully between actually observed exercise behavior (proximal exercise indicator) and associated physiological or psychological variables (distal exercise indicator). Second, a lack of transparent reported reflections on the differing theoretical basis leading to the use of specific implicit measures was observed. Implicit measures should be applied purposefully, taking into consideration the individual advantages or disadvantages of the measures. Third, 12 studies were rated as providing first-grade evidence (lowest grade of evidence), five represent second-grade and three were rated as third-grade evidence. There is a dramatic lack of experimental studies, which are essential for illustrating the cause-effect relation between automatic evaluations of exercising and exercise and investigating under which conditions automatic evaluations of exercising influence behavior. Conclusions about the necessity of exercise interventions targeted at the alteration of automatic evaluations of exercising should therefore not be drawn too hastily. PMID:29250022

  14. Heating 7.2 user`s manual

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

    Childs, K.W.

    1993-02-01

    HEATING is a general-purpose conduction heat transfer program written in Fortran 77. HEATING can solve steady-state and/or transient heat conduction problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- andmore » position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General gray-body radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a runtime memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution, and conjugate gradient. Transient problems may be solved using any one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method. The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.« less

  15. Heating 7. 2 user's manual

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

    Childs, K.W.

    1993-02-01

    HEATING is a general-purpose conduction heat transfer program written in Fortran 77. HEATING can solve steady-state and/or transient heat conduction problems in one-, two-, or three-dimensional Cartesian, cylindrical, or spherical coordinates. A model may include multiple materials, and the thermal conductivity, density, and specific heat of each material may be both time- and temperature-dependent. The thermal conductivity may also be anisotropic. Materials may undergo change of phase. Thermal properties of materials may be input or may be extracted from a material properties library. Heat-generation rates may be dependent on time, temperature, and position, and boundary temperatures may be time- andmore » position-dependent. The boundary conditions, which may be surface-to-environment or surface-to-surface, may be specified temperatures or any combination of prescribed heat flux, forced convection, natural convection, and radiation. The boundary condition parameters may be time- and/or temperature-dependent. General gray-body radiation problems may be modeled with user-defined factors for radiant exchange. The mesh spacing may be variable along each axis. HEATING uses a runtime memory allocation scheme to avoid having to recompile to match memory requirements for each specific problem. HEATING utilizes free-form input. Three steady-state solution techniques are available: point-successive-overrelaxation iterative method with extrapolation, direct-solution, and conjugate gradient. Transient problems may be solved using any one of several finite-difference schemes: Crank-Nicolson implicit, Classical Implicit Procedure (CIP), Classical Explicit Procedure (CEP), or Levy explicit method. The solution of the system of equations arising from the implicit techniques is accomplished by point-successive-overrelaxation iteration and includes procedures to estimate the optimum acceleration parameter.« less

  16. Changes of explicitly and implicitly measured self-esteem in the treatment of major depression: evidence for implicit self-esteem compensation.

    PubMed

    Wegener, Ingo; Geiser, Franziska; Alfter, Susanne; Mierke, Jan; Imbierowicz, Katrin; Kleiman, Alexandra; Koch, Anne Sarah; Conrad, Rupert

    2015-04-01

    Self-esteem has been claimed to be an important factor in the development and maintenance of depression. Whereas explicit self-esteem is usually reduced in depressed individuals, studies on implicitly measured self-esteem in depression exhibit a more heterogeneous pattern of results, and the role of implicit self-esteem in depression is still ambiguous. Previous research on implicit self-esteem compensation (ISEC) revealed that implicit self-esteem can mirror processes of self-esteem compensation under conditions that threaten self-esteem. We assume that depressed individuals experience a permanent threat to their selves resulting in enduring processes of ISEC. We hypothesize that ISEC as measured by implicit self-esteem will decrease when individuals recover from depression. 45 patients with major depression received an integrative in-patient treatment in the Psychosomatic University Hospital Bonn, Germany. Depression was measured by the depression score of the Hospital Anxiety and Depression Scale (HADS-D). Self-esteem was assessed explicitly using the Rosenberg Self-Esteem Scale (RSES) and implicitly by the Implicit Association Test (IAT) and the Name Letter Test (NLT). As expected for a successful treatment of depression, depression scores declined during the eight weeks of treatment and explicit self-esteem rose. In line with our hypothesis, both measures of implicit self-esteem decreased, indicating reduced processes of ISEC. It still remains unclear, under which conditions there is an overlap of measures of implicit and explicit self-esteem. The results lend support to the concept of ISEC and demonstrate the relevance of implicit self-esteem and self-esteem compensation for the understanding of depression. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Primary motor and premotor cortex in implicit sequence learning--evidence for competition between implicit and explicit human motor memory systems.

    PubMed

    Kantak, Shailesh S; Mummidisetty, Chaithanya K; Stinear, James W

    2012-09-01

    Implicit and explicit memory systems for motor skills compete with each other during and after motor practice. Primary motor cortex (M1) is known to be engaged during implicit motor learning, while dorsal premotor cortex (PMd) is critical for explicit learning. To elucidate the neural substrates underlying the interaction between implicit and explicit memory systems, adults underwent a randomized crossover experiment of anodal transcranial direct current stimulation (AtDCS) applied over M1, PMd or sham stimulation during implicit motor sequence (serial reaction time task, SRTT) practice. We hypothesized that M1-AtDCS during practice will enhance online performance and offline learning of the implicit motor sequence. In contrast, we also hypothesized that PMd-AtDCS will attenuate performance and retention of the implicit motor sequence. Implicit sequence performance was assessed at baseline, at the end of acquisition (EoA), and 24 h after practice (retention test, RET). M1-AtDCS during practice significantly improved practice performance and supported offline stabilization compared with Sham tDCS. Performance change from EoA to RET revealed that PMd-AtDCS during practice attenuated offline stabilization compared with M1-AtDCS and sham stimulation. The results support the role of M1 in implementing online performance gains and offline stabilization for implicit motor sequence learning. In contrast, enhancing the activity within explicit motor memory network nodes such as the PMd during practice may be detrimental to offline stabilization of the learned implicit motor sequence. These results support the notion of competition between implicit and explicit motor memory systems and identify underlying neural substrates that are engaged in this competition. © 2012 The Authors. European Journal of Neuroscience © 2012 Federation of European Neuroscience Societies and Blackwell Publishing Ltd.

  18. Canadian Association of General Surgeons position statement: recommendations for surgeons with blood-borne communicable diseases.

    PubMed

    Cleary, Sean; Doucette, Karen; Doig, Christopher J; Coffin, Carla; Grant, David; Dixon, Elijah

    2016-04-01

    The potential for transmission of hematogenously transmitted pathogens during exposure-prone procedures is a clinically important concern to both patients and surgeons. There is inconsistency among regulatory bodies in Canada regarding the management of infection risk among surgeons, particularly with regard to screening and the postexposure management of infected surgeons. The Canadian Association of General Surgeons commissioned a task force to review the evidence regarding the management of blood-borne pathogens and transmission risk during surgical procedures. The results of this review indicate a need for several jurisdictions to update their guidelines to reflect current evidence-based practices.

  19. Psychosocial stress factors and intention to leave job: differences between foreign-born and Finnish-born general practitioners.

    PubMed

    Kuusio, Hannamaria; Heponiemi, Tarja; Vänskä, Jukka; Aalto, Anna-Mari; Ruskoaho, Juho; Elovainio, Marko

    2013-06-01

    Physicians' high dropout rate is a significant problem in primary care in many countries. One solution to this issue is to recruit internationally mobile physicians. This study explores the role of psychosocial factors in explaining intention to leave among GPs including potential differences between foreign-born and Finnish GPs. A cross-sectional questionnaire was sent to randomly-selected Finnish physicians (n = 7000) and all foreign-born physicians (n = 1297) living in Finland in the year 2010. The questionnaire was returned by 4333 physicians, of whom 832 were GPs. Of those 176 were foreign-born GPs. Intention to leave was more common among foreign-born GPs (59%) than among Finnish GPs (52%). High job demands were associated with higher intention to leave from primary care both in foreign-born (OR 1.90) and Finnish GPs (OR 2.20). This association remained among foreign-born GPs after adjusted the model for the country of origin or the reason for migration (OR 1.80, 1.82). Lack of job control, patient-related stress, and stresses related to teamwork were associated with higher intention to leave only among Finnish GPs (ORs 0.45, 1.75 and 1.99). There may be cultural differences in the psychosocial factors that enhance or prevent job involvement among physicians. Thus, novel thinking is needed in organizational development of GP work in order to better understand foreign-born physicians' specific needs in a target country. This study also suggests that lightening workload could help to attract more GPs, both foreign-born and Finnish, to primary care.

  20. Medical School Experiences Associated with Change in Implicit Racial Bias Among 3547 Students: A Medical Student CHANGES Study Report.

    PubMed

    van Ryn, Michelle; Hardeman, Rachel; Phelan, Sean M; Burgess, Diana J; Dovidio, John F; Herrin, Jeph; Burke, Sara E; Nelson, David B; Perry, Sylvia; Yeazel, Mark; Przedworski, Julia M

    2015-12-01

    Physician implicit (unconscious, automatic) bias has been shown to contribute to racial disparities in medical care. The impact of medical education on implicit racial bias is unknown. To examine the association between change in student implicit racial bias towards African Americans and student reports on their experiences with 1) formal curricula related to disparities in health and health care, cultural competence, and/or minority health; 2) informal curricula including racial climate and role model behavior; and 3) the amount and favorability of interracial contact during school. Prospective observational study involving Web-based questionnaires administered during first (2010) and last (2014) semesters of medical school. A total of 3547 students from a stratified random sample of 49 U.S. medical schools. Change in implicit racial attitudes as assessed by the Black-White Implicit Association Test administered during the first semester and again during the last semester of medical school. In multivariable modeling, having completed the Black-White Implicit Association Test during medical school remained a statistically significant predictor of decreased implicit racial bias (-5.34, p ≤ 0.001: mixed effects regression with random intercept across schools). Students' self-assessed skills regarding providing care to African American patients had a borderline association with decreased implicit racial bias (-2.18, p = 0.056). Having heard negative comments from attending physicians or residents about African American patients (3.17, p = 0.026) and having had unfavorable vs. very favorable contact with African American physicians (18.79, p = 0.003) were statistically significant predictors of increased implicit racial bias. Medical school experiences in all three domains were independently associated with change in student implicit racial attitudes. These findings are notable given that even small differences in implicit racial attitudes have been shown to affect behavior and that implicit attitudes are developed over a long period of repeated exposure and are difficult to change.

  1. Threats or violence from patients was associated with turnover intention among foreign-born GPs - a comparison of four workplace factors associated with attitudes of wanting to quit one's job as a GP.

    PubMed

    Eneroth, Mari; Gustafsson Sendén, Marie; Schenck Gustafsson, Karin; Wall, Maja; Fridner, Ann

    2017-06-01

    General practitioners (GPs) are crucial in medical healthcare, but there is currently a shortage of GPs in Sweden and elsewhere. Recruitment of GPs from abroad is essential, but foreign-born physicians face difficulties at work that may be related to turnover intention, i.e. wanting to quit one's job. The study aims to explore the reasons to why foreign-born GPs may intend to quit their job. Survey data were used to compare four work-related factors that can be associated with turnover intentions; patient-related stress, threats or violence from patients, control of work pace, and empowering leadership, among native-born and foreign-born GPs. These work-related factors were subsequently examined in relation to turnover intention among the foreign-born GPs by means of linear hierarchical regression analyses. The questionnaire consisted of items from the QPS Nordic and items constructed by the authors. A primary care setting in a central area of Sweden. Native-born (n = 208) and foreign-born GPs (n = 73). Turnover intention was more common among foreign-born GPs (19.2% compared with 14.9%), as was the experience of threats or violence from patients (22% compared with 3% of the native-born GPs). Threats or violence was also associated with increased turnover intention. Control of work pace and an empowering leadership was associated with reduced turnover intention. The organisations need to recognise that foreign-born GPs may face increased rates of threats and/or violence from patients, which may ultimately cause job turnover and be harmful to the exposed individual.

  2. The relative kicking frequency of infants born full-term and preterm during learning and short-term and long-term memory periods of the mobile paradigm.

    PubMed

    Heathcock, Jill C; Bhat, Anjana N; Lobo, Michele A; Galloway, James C

    2005-01-01

    Infants born preterm differ in their spontaneous kicking, as well as their learning and memory abilities in the mobile paradigm, compared with infants born full-term. In the mobile paradigm, a supine infant's ankle is tethered to a mobile so that leg kicks cause a proportional amount of mobile movement. The purpose of this study was to investigate the relative kicking frequency of the tethered (right) and nontethered (left) legs in these 2 groups of infants. Ten infants born full-term and 10 infants born preterm (<33 weeks gestational age, <2,500 g) and 10 comparison infants participated in the study. The relative kicking frequencies of the tethered and nontethered legs were analyzed during learning and short-term and long-term memory periods of the mobile paradigm. Infants born full-term showed an increase in the relative kicking frequency of the tethered leg during the learning period and the short-term memory period but not for the long-term memory period. Infants born preterm did not show a change in kicking pattern for learning or memory periods, and consistently kicked both legs in relatively equal amounts. Infants born full-term adapted their baseline kicking frequencies in a task-specific manner to move the mobile and then retained this adaptation for the short-term memory period. In contrast, infants born preterm showed no adaptation, suggesting a lack of purposeful leg control. This lack of control may reflect a general decrease in the ability of infants born preterm to use their limb movements to interact with their environment. As such, the mobile paradigm may be clinically useful in the early assessment and intervention of infants born preterm and at risk for future impairment.

  3. Threats or violence from patients was associated with turnover intention among foreign-born GPs – a comparison of four workplace factors associated with attitudes of wanting to quit one’s job as a GP

    PubMed Central

    Eneroth, Mari; Gustafsson Sendén, Marie; Schenck Gustafsson, Karin; Wall, Maja; Fridner, Ann

    2017-01-01

    Objective General practitioners (GPs) are crucial in medical healthcare, but there is currently a shortage of GPs in Sweden and elsewhere. Recruitment of GPs from abroad is essential, but foreign-born physicians face difficulties at work that may be related to turnover intention, i.e. wanting to quit one’s job. The study aims to explore the reasons to why foreign-born GPs may intend to quit their job. Design Survey data were used to compare four work-related factors that can be associated with turnover intentions; patient-related stress, threats or violence from patients, control of work pace, and empowering leadership, among native-born and foreign-born GPs. These work-related factors were subsequently examined in relation to turnover intention among the foreign-born GPs by means of linear hierarchical regression analyses. The questionnaire consisted of items from the QPS Nordic and items constructed by the authors. Setting A primary care setting in a central area of Sweden. Subjects Native-born (n = 208) and foreign-born GPs (n = 73). Results Turnover intention was more common among foreign-born GPs (19.2% compared with 14.9%), as was the experience of threats or violence from patients (22% compared with 3% of the native-born GPs). Threats or violence was also associated with increased turnover intention. Control of work pace and an empowering leadership was associated with reduced turnover intention. Practice implications The organisations need to recognise that foreign-born GPs may face increased rates of threats and/or violence from patients, which may ultimately cause job turnover and be harmful to the exposed individual. PMID:28587508

  4. Kinematic Structural Modelling in Bayesian Networks

    NASA Astrophysics Data System (ADS)

    Schaaf, Alexander; de la Varga, Miguel; Florian Wellmann, J.

    2017-04-01

    We commonly capture our knowledge about the spatial distribution of distinct geological lithologies in the form of 3-D geological models. Several methods exist to create these models, each with its own strengths and limitations. We present here an approach to combine the functionalities of two modeling approaches - implicit interpolation and kinematic modelling methods - into one framework, while explicitly considering parameter uncertainties and thus model uncertainty. In recent work, we proposed an approach to implement implicit modelling algorithms into Bayesian networks. This was done to address the issues of input data uncertainty and integration of geological information from varying sources in the form of geological likelihood functions. However, one general shortcoming of implicit methods is that they usually do not take any physical constraints into consideration, which can result in unrealistic model outcomes and artifacts. On the other hand, kinematic structural modelling intends to reconstruct the history of a geological system based on physically driven kinematic events. This type of modelling incorporates simplified, physical laws into the model, at the cost of a substantial increment of usable uncertain parameters. In the work presented here, we show an integration of these two different modelling methodologies, taking advantage of the strengths of both of them. First, we treat the two types of models separately, capturing the information contained in the kinematic models and their specific parameters in the form of likelihood functions, in order to use them in the implicit modelling scheme. We then go further and combine the two modelling approaches into one single Bayesian network. This enables the direct flow of information between the parameters of the kinematic modelling step and the implicit modelling step and links the exclusive input data and likelihoods of the two different modelling algorithms into one probabilistic inference framework. In addition, we use the capabilities of Noddy to analyze the topology of structural models to demonstrate how topological information, such as the connectivity of two layers across an unconformity, can be used as a likelihood function. In an application to a synthetic case study, we show that our approach leads to a successful combination of the two different modelling concepts. Specifically, we show that we derive ensemble realizations of implicit models that now incorporate the knowledge of the kinematic aspects, representing an important step forward in the integration of knowledge and a corresponding estimation of uncertainties in structural geological models.

  5. Fitts’ Law in the Control of Isometric Grip Force With Naturalistic Targets

    PubMed Central

    Thumser, Zachary C.; Slifkin, Andrew B.; Beckler, Dylan T.; Marasco, Paul D.

    2018-01-01

    Fitts’ law models the relationship between amplitude, precision, and speed of rapid movements. It is widely used to quantify performance in pointing tasks, study human-computer interaction, and generally to understand perceptual-motor information processes, including research to model performance in isometric force production tasks. Applying Fitts’ law to an isometric grip force task would allow for quantifying grasp performance in rehabilitative medicine and may aid research on prosthetic control and design. We examined whether Fitts’ law would hold when participants attempted to accurately produce their intended force output while grasping a manipulandum when presented with images of various everyday objects (we termed this the implicit task). Although our main interest was the implicit task, to benchmark it and establish validity, we examined performance against a more standard visual feedback condition via a digital force-feedback meter on a video monitor (explicit task). Next, we progressed from visual force feedback with force meter targets to the same targets without visual force feedback (operating largely on feedforward control with tactile feedback). This provided an opportunity to see if Fitts’ law would hold without vision, and allowed us to progress toward the more naturalistic implicit task (which does not include visual feedback). Finally, we changed the nature of the targets from requiring explicit force values presented as arrows on a force-feedback meter (explicit targets) to the more naturalistic and intuitive target forces implied by images of objects (implicit targets). With visual force feedback the relation between task difficulty and the time to produce the target grip force was predicted by Fitts’ law (average r2 = 0.82). Without vision, average grip force scaled accurately although force variability was insensitive to the target presented. In contrast, images of everyday objects generated more reliable grip forces without the visualized force meter. In sum, population means were well-described by Fitts’ law for explicit targets with vision (r2 = 0.96) and implicit targets (r2 = 0.89), but not as well-described for explicit targets without vision (r2 = 0.54). Implicit targets should provide a realistic see-object-squeeze-object test using Fitts’ law to quantify the relative speed-accuracy relationship of any given grasper. PMID:29773999

  6. Practical solutions to implementing "Born Semantic" data systems

    NASA Astrophysics Data System (ADS)

    Leadbetter, A.; Buck, J. J. H.; Stacey, P.

    2015-12-01

    The concept of data being "Born Semantic" has been proposed in recent years as a Semantic Web analogue to the idea of data being "born digital"[1], [2]. Within the "Born Semantic" concept, data are captured digitally and at a point close to the time of creation are annotated with markup terms from semantic web resources (controlled vocabularies, thesauri or ontologies). This allows heterogeneous data to be more easily ingested and amalgamated in near real-time due to the standards compliant annotation of the data. In taking the "Born Semantic" proposal from concept to operation, a number of difficulties have been encountered. For example, although there are recognised methods such as Header, Dictionary, Triples [3] for the compression, publication and dissemination of large volumes of triples these systems are not practical to deploy in the field on low-powered (both electrically and computationally) devices. Similarly, it is not practical for instruments to output fully formed semantically annotated data files if they are designed to be plugged into a modular system and the data to be centrally logged in the field as is the case on Argo floats and oceanographic gliders where internal bandwidth becomes an issue [2]. In light of these issues, this presentation will concentrate on pragmatic solutions being developed to the problem of generating Linked Data in near real-time systems. Specific examples from the European Commission SenseOCEAN project where Linked Data systems are being developed for autonomous underwater platforms, and from work being undertaken in the streaming of data from the Irish Galway Bay Cable Observatory initiative will be highlighted. Further, developments of a set of tools for the LogStash-ElasticSearch software ecosystem to allow the storing and retrieval of Linked Data will be introduced. References[1] A. Leadbetter & J. Fredericks, We have "born digital" - now what about "born semantic"?, European Geophysical Union General Assembly, 2014.[2] J. Buck & A. Leadbetter, Born semantic: linking data from sensors to users and balancing hardware limitations with data standards, European Geophysical Union General Assembly, 2015.[3] J. Fernandez et al., Binary RDF Representation for Publication and Exchange (HDT), Web Semantics 19:22-41, 2013.

  7. Implicit Learning as an Ability

    ERIC Educational Resources Information Center

    Kaufman, Scott Barry; DeYoung, Caroline G.; Gray, Jeremy R.; Jimenez, Luis; Brown, Jamie; Mackintosh, Nicholas

    2010-01-01

    The ability to automatically and implicitly detect complex and noisy regularities in the environment is a fundamental aspect of human cognition. Despite considerable interest in implicit processes, few researchers have conceptualized implicit learning as an ability with meaningful individual differences. Instead, various researchers (e.g., Reber,…

  8. Implicit attitudes, emotions, and helping intentions of mental health workers toward their clients.

    PubMed

    Brener, Loren; Rose, Grenville; von Hippel, Courtney; Wilson, Hannah

    2013-06-01

    The attitudes of mental health care workers toward their clients may influence the quality of care they provide. There is growing recognition of the role of implicit attitudes in behavior toward people with stigmatized illnesses, such as mental illness, and of the need to measure these separately from explicit attitudes. Seventy-four mental health workers completed implicit and explicit measure of attitudes toward people with mental illness. The participants were also asked about their intention to help people with mental illness and their emotional reactions toward people with a mental illness. The findings show that the implicit attitudes of the health workers toward clients with a mental illness are somewhat negative despite the fact that their explicit attitudes are somewhat positive. Although both implicit and explicit attitudes predicted negative emotions, only implicit attitudes were related to helping intentions. This study highlights the association between implicit attitudes and behavioral intentions and confirms the importance of addressing implicit attitudes in mental health research.

  9. Cultural variation in implicit independence: An extension of Kitayama et al. ().

    PubMed

    Park, Jiyoung; Uchida, Yukiko; Kitayama, Shinobu

    2016-08-01

    Previous research shows that European Americans are consistently more independent (or less interdependent) than Japanese when implicit indices are used to assess independence (vs. interdependence). The present work extended this evidence by including a novel implicit association test (IAT), as an index of implicit attitude towards independence and interdependence. Consistent with the previous findings, as compared to Japanese, Americans were significantly higher in multiple indices of implicit independence (vs. interdependence) including personal (vs. social) self-definition, experience of disengaging (vs. engaging) emotions and personal (vs. social) form of happiness. Furthermore, as compared to Japanese, Americans had a significantly more positive implicit attitude towards independence assessed with the IAT. As also observed in the previous research, explicit measures showed inconsistent cross-cultural patterns. Lastly, we observed little statistical within-culture coherence among the implicit measures of independence (vs. interdependence), consistent with a view that the implicit indices capture alternative ways for individuals to achieve the cultural mandate of independence or interdependence. © 2015 International Union of Psychological Science.

  10. Implicit motives, explicit traits, and task and contextual performance at work.

    PubMed

    Lang, Jonas W B; Zettler, Ingo; Ewen, Christian; Hülsheger, Ute R

    2012-11-01

    Personality psychologists have long argued that explicit traits (as measured by questionnaires) channel the expression of implicit motives (as measured by coding imaginative verbal behavior) such that both interact in the prediction of relevant life outcome variables. In the present research, we apply these ideas in the context of industrial and organizational psychology and propose that 2 explicit traits work as channels for the expression of 3 core implicit motives in task and contextual job performance (extraversion for implicit affiliation and implicit power; explicit achievement for implicit achievement). As a test of these theoretical ideas, we report a study in which employees (N = 241) filled out a questionnaire booklet and worked on an improved modern implicit motive measure, the operant motive test. Their supervisors rated their task and contextual performance. Results support 4 of the 6 theoretical predictions and show that interactions between implicit motives and explicit traits increase the explained criterion variance in both task and contextual performance. (c) 2012 APA, all rights reserved.

  11. Implicit and explicit attitudes towards conventional and complementary and alternative medicine treatments: Introduction of an Implicit Association Test.

    PubMed

    Green, James A; Hohmann, Cynthia; Lister, Kelsi; Albertyn, Riani; Bradshaw, Renee; Johnson, Christine

    2016-06-01

    This study examined associations between anticipated future health behaviour and participants' attitudes. Three Implicit Association Tests were developed to assess safety, efficacy and overall attitude. They were used to examine preference associations between conventional versus complementary and alternative medicine among 186 participants. A structural equation model suggested only a single implicit association, rather than three separate domains. However, this single implicit association predicted additional variance in anticipated future use of complementary and alternative medicine beyond explicit. Implicit measures should give further insight into motivation for complementary and alternative medicine use. © The Author(s) 2014.

  12. Implicit cognitive processes in psychopathology: an introduction.

    PubMed

    Wiers, Reinout W; Teachman, Bethany A; De Houwer, Jan

    2007-06-01

    Implicit or automatic processes are important in understanding the etiology and maintenance of psychopathological problems. In order to study implicit processes in psychopathology, measures are needed that are valid and reliable when applied to clinical problems. One of the main topics in this special issue concerns the development and validation of new or modified implicit tests in different domains of psychopathology. The other main topic concerns the prediction of clinical outcomes and new ways to directly influence implicit processes in psychopathology. We summarize the contributions to this special issue and discuss how they further our knowledge of implicit processes in psychopathology and how to measure them.

  13. Examining the Presence, Consequences, and Reduction of Implicit Bias in Health Care: A Narrative Review

    PubMed Central

    Zestcott, Colin A.; Blair, Irene V.; Stone, Jeff

    2016-01-01

    Recent evidence suggests that one possible cause of disparities in health outcomes for stigmatized groups is the implicit biases held by health care providers. In response, several health care organizations have called for, and developed, new training in implicit bias for their providers. This review examines current evidence on the role that provider implicit bias may play in health disparities, and whether training in implicit bias can effectively reduce the biases that providers exhibit. Directions for future research on the presence and consequences of provider implicit bias, and best practices for training to reduce such bias, will be discussed. PMID:27547105

  14. Health care usage among immigrants and native-born elderly populations in eleven European countries: results from SHARE

    PubMed Central

    Guillén, Montserrat; Crimmins, Eileen M.

    2013-01-01

    Differences in health care utilization of immigrants 50 years of age and older relative to the native-born populations in eleven European countries are investigated. Negative binomial and zero-inflated Poisson regression are used to examine differences between immigrants and native-borns in number of doctor visits, visits to general practitioners, and hospital stays using the 2004 Survey of Health, Ageing, and Retirement in Europe database. In the pooled European sample and in some individual countries, older immigrants use from 13 to 20% more health services than native-borns after demographic characteristics are controlled. After controlling for the need for health care, differences between immigrants and native-borns in the use of physicians, but not hospitals, are reduced by about half. These are not changed much with the incorporation of indicators of socioeconomic status and extra insurance coverage. Higher country-level relative expenditures on health, paying physicians a fee-for-service, and physician density are associated with higher usage of physician services among immigrants. PMID:21660564

  15. Height of Northern Jordanian middle-class adults, born 1960-1990 in the response to improving socio-economic conditions.

    PubMed

    Abu Dalou, Ahmad Yosuf

    2016-09-01

    The purpose of this study is to document and explain secular trends in stature among Northern Jordanian men and women between the years of birth 1960 and 1990, as they relate to overall per capita socio-economic improvement, the stature of 360 adults from two Northern governorates, those of Jerash and Irbid, was measured. General linear model (GLM) was used to examine the effect of birth-decade, education level of subject, and their interaction on mean stature of each sex separately. GLM results revealed that women who were born during the following three decades pooled together (1951-1980) did not differ significantly in mean stature from those born during (1981-1990). Among men, stature of those born in the two pooled birth-decades together (1951-1970) did not significantly differ of those were born in the two pooled birth-decades (1971-1990). Copyright © 2016. Published by Elsevier B.V.

  16. Implicit Statistical Learning and Language Skills in Bilingual Children

    ERIC Educational Resources Information Center

    Yim, Dongsun; Rudoy, John

    2013-01-01

    Purpose: Implicit statistical learning in 2 nonlinguistic domains (visual and auditory) was used to investigate (a) whether linguistic experience influences the underlying learning mechanism and (b) whether there are modality constraints in predicting implicit statistical learning with age and language skills. Method: Implicit statistical learning…

  17. Implicit affectivity in patients with borderline personality disorder.

    PubMed

    Dukalski, Bibiana; Quirin, Markus; Kersting, Anette; Suslow, Thomas; Donges, Uta-Susan

    2017-01-01

    It has been argued that borderline personality disorder (BPD) is related to an enhanced affective reactivity. According to findings from research based on self-report, individuals with BPD develop and feel more negative and less positive affect than healthy individuals. Implicit affectivity, which can be measured using indirect assessment methods, relates to processes of the impulsive, intuitive system. In the present study, implicit and explicit affectivity was examined in patients suffering from BPD compared to healthy persons. Thirty-five women with BPD and 35 healthy women participated in the study. Implicit affectivity was assessed using the Implicit Positive and Negative Affect Test (IPANAT). Measures of explicit state and trait affectivity were also administered. BPD women had lower explicit positive state and trait affect scores and higher negative state and trait affect scores than healthy women. They had also lower implicit positive affect but they did not differ from healthy women regarding implicit negative affect. Total number of comorbid disorders was correlated with both implicit positive and implicit negative affect. According to our data, BPD patients exhibit reduced implicit positive affect as well as reduced explicit positive affect compared to healthy persons. According to our IPANAT data, BPD patients are characterized by a normal disposition to develop negative affective reactions which is in line with a number of findings from psycho-physiological research on BPD. Self-reports of negative affectivity in BPD could be biased by negative distortion.

  18. Context Effects of Alcohol Availability at Home: Implicit Alcohol Associations and the Prediction of Adolescents' Drinking Behavior.

    PubMed

    Peeters, Margot; Koning, Ina; Monshouwer, Karin; Vollebergh, Wilma A M; Wiers, Reinout W

    2016-09-01

    Recent studies suggest that the predictive effect of implicit alcohol associations is context dependent. Findings indicate that implicit associations are more easily retrieved in an alcohol-associated setting or context (e.g., bar) compared with a neutral setting. In line with this reasoning, we hypothesized that alcohol availability at home might moderate the relationship between implicit alcohol associations and future drinking behavior of adolescents. Participants were 262 at-risk adolescents (235 boys, 27 girls, adolescents with externalizing behavioral problems) with a mean age of 14.11 years (SD = 0.86, age range: 12-16 years) at baseline. Adolescents completed a questionnaire and a modified version of the Implicit Association Test (i.e., Single Category Implicit Association Test; SC-IAT). Stronger implicit alcohol associations predicted increase in frequency of alcohol use, only in adolescents who indicated that alcohol was available at home. No moderating effects were found for increase in quantity of alcohol use and problematic alcohol use, suggesting that implicit alcohol associations particularly influence the decision of whether to drink in adolescence. The findings illustrate that the availability of alcohol in the home setting influences adolescents' implicit alcohol associations and consequently affects the frequency of alcohol use. In this way, alcohol availability at home may be an important contextual factor to consider when examining the effect of implicit alcohol associations on the future drinking behavior of adolescents.

  19. Using implicit attitudes of exercise importance to predict explicit exercise dependence symptoms and exercise behaviors.

    PubMed

    Forrest, Lauren N; Smith, April R; Fussner, Lauren M; Dodd, Dorian R; Clerkin, Elise M

    2016-01-01

    "Fast" (i.e., implicit) processing is relatively automatic; "slow" (i.e., explicit) processing is relatively controlled and can override automatic processing. These different processing types often produce different responses that uniquely predict behaviors. In the present study, we tested if explicit, self-reported symptoms of exercise dependence and an implicit association of exercise as important predicted exercise behaviors and change in problematic exercise attitudes. We assessed implicit attitudes of exercise importance and self-reported symptoms of exercise dependence at Time 1. Participants reported daily exercise behaviors for approximately one month, and then completed a Time 2 assessment of self-reported exercise dependence symptoms. Undergraduate males and females (Time 1, N = 93; Time 2, N = 74) tracked daily exercise behaviors for one month and completed an Implicit Association Test assessing implicit exercise importance and subscales of the Exercise Dependence Questionnaire (EDQ) assessing exercise dependence symptoms. Implicit attitudes of exercise importance and Time 1 EDQ scores predicted Time 2 EDQ scores. Further, implicit exercise importance and Time 1 EDQ scores predicted daily exercise intensity while Time 1 EDQ scores predicted the amount of days exercised. Implicit and explicit processing appear to uniquely predict exercise behaviors and attitudes. Given that different implicit and explicit processes may drive certain exercise factors (e.g., intensity and frequency, respectively), these behaviors may contribute to different aspects of exercise dependence.

  20. Dissociation between implicit and explicit expectancies of cannabis use in adolescence.

    PubMed

    Schmits, Emilie; Maurage, Pierre; Thirion, Romain; Quertemont, Etienne

    2015-12-30

    Cannabis is one of the most commonly drugs used by teenagers. Expectancies about its effects play a crucial role in cannabis consumption. Various tools have been used to assess expectancies, mainly self-report questionnaires measuring explicit expectancies, but implicit measures based on experimental tasks have also been developed, measuring implicit expectancies. The aim of this study was to simultaneously assess implicit/explicit expectancies related to cannabis among adolescent users and non-users. 130 teenagers attending school (55 girls) were enrolled (Age: M=16.40 years); 43.84% had never used cannabis ("non-users") and 56.16% had used cannabis ("users"). They completed self-report questionnaires evaluating cannabis use, cannabis-related problems, effect expectancies (explicit expectancies), alcohol use, social and trait anxiety, depression, as well as three Implicit Association Tests (IAT) assessing implicit expectancies. Adolescents manifested more implicit affective associations (relaxation, excitation, negative) than neutral ones regarding cannabis. These were not related to explicit expectancies. Cannabis users reported more implicit relaxation expectancies and less negative explicit expectancies than non-users. The frequency of use and related problems were positively associated with the explicit expectancies regarding relaxation and enhancement, and were negatively associated with negative explicit expectancies and negative implicit expectancies. Findings indicate that implicit and explicit expectancies play different roles in cannabis use by adolescents. The implications for experimentation and prevention are discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Using implicit attitudes of exercise importance to predict explicit exercise dependence symptoms and exercise behaviors

    PubMed Central

    Forrest, Lauren N.; Smith, April R.; Fussner, Lauren M.; Dodd, Dorian R.; Clerkin, Elise M.

    2015-01-01

    Objectives ”Fast” (i.e., implicit) processing is relatively automatic; “slow” (i.e., explicit) processing is relatively controlled and can override automatic processing. These different processing types often produce different responses that uniquely predict behaviors. In the present study, we tested if explicit, self-reported symptoms of exercise dependence and an implicit association of exercise as important predicted exercise behaviors and change in problematic exercise attitudes. Design We assessed implicit attitudes of exercise importance and self-reported symptoms of exercise dependence at Time 1. Participants reported daily exercise behaviors for approximately one month, and then completed a Time 2 assessment of self-reported exercise dependence symptoms. Method Undergraduate males and females (Time 1, N = 93; Time 2, N = 74) tracked daily exercise behaviors for one month and completed an Implicit Association Test assessing implicit exercise importance and subscales of the Exercise Dependence Questionnaire (EDQ) assessing exercise dependence symptoms. Results Implicit attitudes of exercise importance and Time 1 EDQ scores predicted Time 2 EDQ scores. Further, implicit exercise importance and Time 1 EDQ scores predicted daily exercise intensity while Time 1 EDQ scores predicted the amount of days exercised. Conclusion Implicit and explicit processing appear to uniquely predict exercise behaviors and attitudes. Given that different implicit and explicit processes may drive certain exercise factors (e.g., intensity and frequency, respectively), these behaviors may contribute to different aspects of exercise dependence. PMID:26195916

  2. Decisions among the Undecided: Implicit Attitudes Predict Future Voting Behavior of Undecided Voters

    PubMed Central

    Lundberg, Kristjen B.; Payne, B. Keith

    2014-01-01

    Implicit attitudes have been suggested as a key to unlock the hidden preferences of undecided voters. Past research, however, offered mixed support for this hypothesis. The present research used a large nationally representative sample and a longitudinal design to examine the predictive utility of implicit and explicit attitude measures in the 2008 U.S. presidential election. In our analyses, explicit attitudes toward candidates predicted voting better for decided than undecided voters, but implicit candidate attitudes were predictive of voting for both decided and undecided voters. Extending our examination to implicit and explicit racial attitudes, we found the same pattern. Taken together, these results provide convergent evidence that implicit attitudes predict voting about as well for undecided as for decided voters. We also assessed a novel explanation for these effects by evaluating whether implicit attitudes may predict the choices of undecided voters, in part, because they are neglected when people introspect about their confidence. Consistent with this idea, we found that the extremity of explicit but not implicit attitudes was associated with greater confidence. These analyses shed new light on the utility of implicit measures in predicting future behavior among individuals who feel undecided. Considering the prior studies together with this new evidence, the data seem to be consistent that implicit attitudes may be successful in predicting the behavior of undecided voters. PMID:24489666

  3. The role of social capital in explaining mental health inequalities between immigrants and Swedish-born: a population-based cross-sectional study.

    PubMed

    Johnson, Charisse M; Rostila, Mikael; Svensson, Anna C; Engström, Karin

    2017-01-25

    Social capital may theoretically explain health inequalities between social groups, but empirical evidence is lacking. Some studies indicate that social capital may be particularly important for immigrant health. Nearly 16% of Sweden's population are foreign-born immigrants and research has shown them to be susceptible to psychological distress, though significant variation has been found between groups. In this study, we investigate the following hypotheses: 1) if non-refugees have better mental health than Swedish-born, and refugees experience worse mental health than Swedish-born; 2) if mental health status converges with that of Swedish-born with longer duration of residence; and 3) if social capital mediates the effect of immigrant status on psychological distress for different immigrant groups as compared to Swedish-born. This cross-sectional study uses baseline data from the Stockholm Public Health Cohort and includes 50,498 randomly-selected individuals from Stockholm County in 2002, 2006, and 2010. Mental health was measured as psychological distress, using the 12-item General Health Questionnaire. Social capital was measured using indicators of bonding, bridging, and linking social capital. Both cognitive and structural aspects were measured for the latter two indicators. Mediation was tested using logistic regression and the Sobel test. The results show that refugees generally had greater odds of psychological distress than non-refugees compared to their respective Swedish-born counterparts. Among immigrant men, both refugees and non-refugees had significantly greater odds of psychological distress than Swedish-born men. Only refugee women in Sweden 10 years or more had significantly greater odds of psychological distress compared to Swedish-born women. The mediation analysis demonstrated that indicators of social capital mediated the association for all immigrant men (except non-refugees in Sweden 3-9 years) and for refugee women in Sweden 10 years or more. While bonding social capital showed the greatest mediatory role among the three social capital types, adding them together had the strongest explanatory effect. Social capital explains differences in mental health for some immigrant groups, highlighting its role as a potentially important post-migration factor. Increased investment from policy-makers regarding how social capital can be promoted among new arrivals may be important for preventing psychological distress.

  4. Racial Categorization Predicts Implicit Racial Bias in Preschool Children.

    PubMed

    Setoh, Peipei; Lee, Kristy J J; Zhang, Lijun; Qian, Miao K; Quinn, Paul C; Heyman, Gail D; Lee, Kang

    2017-06-12

    This research investigated the relation between racial categorization and implicit racial bias in majority and minority children. Chinese and Indian 3- to 7-year-olds from Singapore (N = 158) categorized Chinese and Indian faces by race and had their implicit and explicit racial biases measured. Majority Chinese children, but not minority Indian children, showed implicit bias favoring own race. Regardless of ethnicity, children's racial categorization performance correlated positively with implicit racial bias. Also, Chinese children, but not Indian children, displayed explicit bias favoring own race. Furthermore, children's explicit bias was unrelated to racial categorization performance and implicit bias. The findings support a perceptual-social linkage in the emergence of implicit racial bias and have implications for designing programs to promote interracial harmony. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

  5. Implicit Bias and Mental Health Professionals: Priorities and Directions for Research.

    PubMed

    Merino, Yesenia; Adams, Leslie; Hall, William J

    2018-06-01

    This Open Forum explores the role of implicit bias along the mental health care continuum, which may contribute to mental health disparities among vulnerable populations. Emerging research shows that implicit bias is prevalent among service providers. These negative or stigmatizing attitudes toward population groups are held at a subconscious level and are automatically activated during practitioner-client encounters. The authors provide examples of how implicit bias may impede access to care, clinical screening and diagnosis, treatment processes, and crisis response. They also discuss how implicit attitudes may manifest at the intersection between mental health and criminal justice institutions. Finally, they discuss the need for more research on the impact of implicit bias on health practices throughout the mental health system, including the development of interventions to address implicit bias among mental health professionals.

  6. Examining the Implicit Relational Assessment Procedure: Four Preliminary Studies

    ERIC Educational Resources Information Center

    Drake, Chad E.; Kellum, Karen Kate; Wilson, Kelly G.; Luoma, Jason B.; Weinstein, Jonathan H.; Adams, Catherine H.

    2010-01-01

    The Implicit Relational Assessment Procedure (IRAP) is a relatively new measure of implicit cognition that tests cognition as relational behavior instead of an associative activity and thus may provide a more specific measure of cognitive repertoires, including those for social biases, than better known implicit measures such as the Implicit…

  7. Explicit versus Implicit Stereotypes: "What Biases Do I Really Hold?"

    ERIC Educational Resources Information Center

    Morgan, Melanie

    2008-01-01

    This article presents an activity in which students explore the impact of implicit stereotypes in everyday interactions while examining issues of attitudinal measurement. Social cognitions that underlie stereotypes often operate implicitly and even unconsciously. Consequently, these implicit attitudes have the potential to affect the way people…

  8. Implicit Referential Meaning with Reference to English Arabic Translation

    ERIC Educational Resources Information Center

    Al-Zughoul, Basem

    2014-01-01

    The purpose of this study is to investigate how English implicit referential meaning is translated into Arabic by analyzing sentences containing implicit referential meanings found in the novel "Harry Potter and the Prisoner of Azkaban". The analysis shows that the translation of English implicit referential meaning into Arabic can be…

  9. Chinese Undergraduates' Explicit and Implicit Attitudes toward Persons with Disabilities

    ERIC Educational Resources Information Center

    Chen, Shuang; Ma, Li; Zhang, Jian-Xin

    2011-01-01

    The present study is aimed at examining implicit and explicit attitudes toward persons with disabilities among Chinese college students. The "Implicit Association Test" was used to measure their implicit attitudes, whereas their explicit attitudes toward persons with disabilities were measured by using a scale of three items.…

  10. Do puzzle pieces and autism puzzle piece logos evoke negative associations?

    PubMed

    Gernsbacher, Morton Ann; Raimond, Adam R; Stevenson, Jennifer L; Boston, Jilana S; Harp, Bev

    2018-02-01

    Puzzle pieces have become ubiquitous symbols for autism. However, puzzle-piece imagery stirs debate between those who support and those who object to its use because they believe puzzle-piece imagery evokes negative associations. Our study empirically investigated whether puzzle pieces evoke negative associations in the general public. Participants' ( N = 400) implicit negative associations were measured with an Implicit Association Task, which is a speeded categorization task, and participants' explicit associations were measured with an Explicit Association Task, which is a standard task for assessing consumers' explicit associations with brands (and images of those brands). Puzzle pieces, both those used as autism logos and those used more generically, evoked negative implicit associations ( t(399) = -5.357, p < 0.001) and negative explicit associations ( z = 4.693, p < 0.001, d = 0.491). Participants explicitly associated puzzle pieces, even generic puzzle pieces, with incompleteness, imperfection, and oddity. Our results bear public policy implications. If an organization's intention for using puzzle-piece imagery is to evoke negative associations, our results suggest the organization's use of puzzle-piece imagery is apt. However, if the organization's intention is to evoke positive associations, our results suggest that puzzle-piece imagery should probably be avoided.

  11. [Implicit value judgments in the measurement of health inequalities].

    PubMed

    Harper, Sam; King, Nicholas B; Meersman, Stephen C; E Reichman, Marsha; Breen, Nancy; Lynch, John

    2014-04-01

    Quantitative estimates of the magnitude, direction, and rate of change of health inequalities play a crucial role in creating and assessing policies aimed at eliminating the disproportionate burden of disease in disadvantaged populations. It is generally assumed that the measurement of health inequalities is a value-neutral process, providing objective data that are then interpreted using normative judgments about whether a particular distribution of health is just, fair, or socially acceptable. We discuss five examples in which normative judgments play a role in the measurement process itself, through either the selection of one measurement strategy to the exclusion of others or the selection of the type, significance, or weight assigned to the variables being measured. Overall, we find that many commonly used measures of inequality are value laden and that the normative judgments implicit in these measures have important consequences for interpreting and responding to health inequalities. Because values implicit in the generation of health inequality measures may lead to radically different interpretations of the same underlying data,we urge researchers to explicitly consider and transparently discuss the normative judgments underlying their measures. We also urge policymakers and other consumers of health inequalities data to pay close attention to the measures on which they base their assessments of current and future health policies.

  12. Implicit value judgments in the measurement of health inequalities.

    PubMed

    Harper, Sam; King, Nicholas B; Meersman, Stephen C; Reichman, Marsha E; Breen, Nancy; Lynch, John

    2010-03-01

    Quantitative estimates of the magnitude, direction, and rate of change of health inequalities play a crucial role in creating and assessing policies aimed at eliminating the disproportionate burden of disease in disadvantaged populations. It is generally assumed that the measurement of health inequalities is a value-neutral process, providing objective data that are then interpreted using normative judgments about whether a particular distribution of health is just, fair, or socially acceptable. We discuss five examples in which normative judgments play a role in the measurement process itself, through either the selection of one measurement strategy to the exclusion of others or the selection of the type, significance, or weight assigned to the variables being measured. Overall, we find that many commonly used measures of inequality are value laden and that the normative judgments implicit in these measures have important consequences for interpreting and responding to health inequalities. Because values implicit in the generation of health inequality measures may lead to radically different interpretations of the same underlying data, we urge researchers to explicitly consider and transparently discuss the normative judgments underlying their measures. We also urge policymakers and other consumers of health inequalities data to pay close attention to the measures on which they base their assessments of current and future health policies.

  13. Electro-cortical implicit race bias does not vary with participants’ race or sex

    PubMed Central

    Mallan, Kimberley M.; Martin, Frances H.; Terry, Deborah J.; Smith, Joanne R.

    2011-01-01

    Earlier research found evidence for electro-cortical race bias towards black target faces in white American participants irrespective of the task relevance of race. The present study investigated whether an implicit race bias generalizes across cultural contexts and racial in- and out-groups. An Australian sample of 56 Chinese and Caucasian males and females completed four oddball tasks that required sex judgements for pictures of male and female Chinese and Caucasian posers. The nature of the background (across task) and of the deviant stimuli (within task) was fully counterbalanced. Event-related potentials (ERPs) to deviant stimuli recorded from three midline sites were quantified in terms of mean amplitude for four components: N1, P2, N2 and a late positive complex (LPC; 350–700 ms). Deviants that differed from the backgrounds in sex or race elicited enhanced LPC activity. These differences were not modulated by participant race or sex. The current results replicate earlier reports of effects of poser race relative to background race on the LPC component of the ERP waveform. In addition, they indicate that an implicit race bias occurs regardless of participant’s or poser’s race and is not confined to a particular cultural context. PMID:21097957

  14. Implicit Priors in Galaxy Cluster Mass and Scaling Relation Determinations

    NASA Technical Reports Server (NTRS)

    Mantz, A.; Allen, S. W.

    2011-01-01

    Deriving the total masses of galaxy clusters from observations of the intracluster medium (ICM) generally requires some prior information, in addition to the assumptions of hydrostatic equilibrium and spherical symmetry. Often, this information takes the form of particular parametrized functions used to describe the cluster gas density and temperature profiles. In this paper, we investigate the implicit priors on hydrostatic masses that result from this fully parametric approach, and the implications of such priors for scaling relations formed from those masses. We show that the application of such fully parametric models of the ICM naturally imposes a prior on the slopes of the derived scaling relations, favoring the self-similar model, and argue that this prior may be influential in practice. In contrast, this bias does not exist for techniques which adopt an explicit prior on the form of the mass profile but describe the ICM non-parametrically. Constraints on the slope of the cluster mass-temperature relation in the literature show a separation based the approach employed, with the results from fully parametric ICM modeling clustering nearer the self-similar value. Given that a primary goal of scaling relation analyses is to test the self-similar model, the application of methods subject to strong, implicit priors should be avoided. Alternative methods and best practices are discussed.

  15. Teacher Education, [strikethrough In]Exclusion, and the Implicit Ideology of "Separate but Equal": An Invitation to a Dialogue

    ERIC Educational Resources Information Center

    Lalvani, Priya; Broderick, Alicia A.; Fine, Michelle; Jacobowitz, Tina; Michelli, Nicholas

    2015-01-01

    In this analytic essay, we initiate a dialogue about the place of disability in a multicultural education framework, and the role of inclusive education in a democracy. Problematizing the common omission of the topic of disability oppression from anti-oppression pedagogies and from social justice education generally, we invite teacher educators…

  16. Iterated Hamiltonian type systems and applications

    NASA Astrophysics Data System (ADS)

    Tiba, Dan

    2018-04-01

    We discuss, in arbitrary dimension, certain Hamiltonian type systems and prove existence, uniqueness and regularity properties, under the independence condition. We also investigate the critical case, define a class of generalized solutions and prove existence and basic properties. Relevant examples and counterexamples are also indicated. The applications concern representations of implicitly defined manifolds and their perturbations, motivated by differential systems involving unknown geometries.

  17. Learner Autonomy in Foreign Language Policies in Vietnamese Universities: An Exploration of Teacher Agency from a Sociocultural Perspective

    ERIC Educational Resources Information Center

    Phan, T. T. Huyen; Hamid, M. Obaidul

    2017-01-01

    Learner autonomy (LA) is generally accepted as an important goal, either explicit or implicit, in language education policies across polities. Fostering LA in educational settings primarily depends on the role of teachers in enacting macro-level policies at the micro level. While various top-down and bottom-up frameworks for language policy…

  18. Beyond the Local/General Divide: English for Academic Purposes and Process Approaches to Cross Disciplinary, Doctoral Writing Support

    ERIC Educational Resources Information Center

    Bastalich, Wendy

    2011-01-01

    One of the outcomes of the policy emphasis upon skills formation in countries like Australia and the UK has been an increase in cross-disciplinary structured programs for higher research degrees raising implicit, but often unexamined, questions about the curriculum and expertise that should inform them. Key insights from applied linguistics and…

  19. A Behavior Analytically Modified Implicit Association Test for Measuring Sexual Categorization of Children

    ERIC Educational Resources Information Center

    Gavin, Amanda; Roche, Bryan; Ruiz, Maria R.; Hogan, Maria; O'Reilly, Anthony

    2012-01-01

    The current study assessed the sexual categorization of children among a random sample of adults from the general population. Twenty-seven males and 27 females (N = 54) were exposed to a categorization task that assessed their ability to discriminate adult- from child-related words and sexual from non-sexual words. Then, in a modified Implicit…

  20. Modulational instability and dynamics of implicit higher-order rogue wave solutions for the Kundu equation

    NASA Astrophysics Data System (ADS)

    Wen, Xiao-Yong; Zhang, Guoqiang

    2018-01-01

    Under investigation in this paper is the Kundu equation, which may be used to describe the propagation process of ultrashort optical pulses in nonlinear optics. The modulational instability of the plane-wave for the possible reason of the formation of the rogue wave (RW) is studied for the system. Based on our proposed generalized perturbation (n,N - n)-fold Darboux transformation (DT), some new higher-order implicit RW solutions in terms of determinants are obtained by means of the generalized perturbation (1,N - 1)-fold DT, when choosing different special parameters, these results will reduce to the RW solutions of the Kaup-Newell (KN) equation, Chen-Lee-Liu (CLL) equation and Gerjikov-Ivanov (GI) equation, respectively. The relevant wave structures are shown graphically, which display abundant interesting wave structures. The dynamical behaviors and propagation stability of the first-order and second-order RW solutions are discussed by using numerical simulations, the higher-order nonlinear terms for the Kundu equation have an impact on the propagation instability of the RW. The method can also be extended to find the higher-order RW or rational solutions of other integrable nonlinear equations.

  1. Bidirectional Transfer between Metaphorical Related Domains in Implicit Learning of Form-Meaning Connections

    PubMed Central

    Yang, Zhiliang; Dienes, Zoltan

    2013-01-01

    People can implicitly learn a connection between linguistic forms and meanings, for example between specific determiners (e.g. this, that…) and the type of nouns to which they apply. Li et al (2013) recently found that transfer of form-meaning connections from a concrete domain (height) to an abstract domain (power) was achieved in a metaphor-consistent way without awareness, showing that unconscious knowledge can be abstract and flexibly deployed. The current study aims to determine whether people transfer knowledge of form-meaning connections not only from a concrete domain to an abstract one, but also vice versa, consistent with metaphor representation being bi-directional. With a similar paradigm as used by Li et al, participants learnt form- meaning connections of different domains (concrete vs. abstract) and then were tested on two kinds of generalizations (same and different domain generalization). As predicted, transfer of form-meaning connections occurred bidirectionally when structural knowledge was unconscious. Moreover, the present study also revealed that more transfer occurred between metaphorically related domains when judgment knowledge was conscious (intuition) rather than unconscious (guess). Conscious and unconscious judgment knowledge may have different functional properties. PMID:23844159

  2. Differential Age Effects for Implicit and Explicit Conceptual Associative Memory

    PubMed Central

    Dew, Ilana T. Z.; Giovanello, Kelly S.

    2010-01-01

    Older adults show disproportionate declines in explicit memory for associative relative to item information. However, the source of these declines is still uncertain. One explanation is a generalized impairment in the processing of associative information. A second explanation is a more specialized impairment in the strategic, effortful recollection of associative information, leaving less effortful forms of associative retrieval preserved. Assessing implicit memory of new associations is a way to distinguish between these viewpoints. To date, mixed findings have emerged from studies of associative priming in aging. One factor that may account for the variability is whether the manipulations inadvertently involve strategic, explicit processes. In 2 experiments we present a novel paradigm of conceptual associative priming in which subjects make speeded associative judgments about unrelated objects. Using a size classification task, Experiment 1 showed equivalent associative priming between young and older adults. Experiment 2 generalized the results of Experiment 1 to an inside/outside classification task, while replicating the typical age-related impairment in associative but not item recognition. Taken together, the findings support the viewpoint that older adults can incidentally encode and retrieve new meaningful associations despite difficulty with the intentional recollection of the same information. PMID:21077717

  3. PROTEUS two-dimensional Navier-Stokes computer code, version 1.0. Volume 2: User's guide

    NASA Technical Reports Server (NTRS)

    Towne, Charles E.; Schwab, John R.; Benson, Thomas J.; Suresh, Ambady

    1990-01-01

    A new computer code was developed to solve the two-dimensional or axisymmetric, Reynolds averaged, unsteady compressible Navier-Stokes equations in strong conservation law form. The thin-layer or Euler equations may also be solved. Turbulence is modeled using an algebraic eddy viscosity model. The objective was to develop a code for aerospace applications that is easy to use and easy to modify. Code readability, modularity, and documentation were emphasized. The equations are written in nonorthogonal body-fitted coordinates, and solved by marching in time using a fully-coupled alternating direction-implicit procedure with generalized first- or second-order time differencing. All terms are linearized using second-order Taylor series. The boundary conditions are treated implicitly, and may be steady, unsteady, or spatially periodic. Simple Cartesian or polar grids may be generated internally by the program. More complex geometries require an externally generated computational coordinate system. The documentation is divided into three volumes. Volume 2 is the User's Guide, and describes the program's general features, the input and output, the procedure for setting up initial conditions, the computer resource requirements, the diagnostic messages that may be generated, the job control language used to run the program, and several test cases.

  4. On a hierarchy of nonlinearly dispersive generalized Korteweg - de Vries evolution equations

    DOE PAGES

    Christov, Ivan C.

    2015-08-20

    We propose a hierarchy of nonlinearly dispersive generalized Korteweg–de Vries (KdV) evolution equations based on a modification of the Lagrangian density whose induced action functional the KdV equation extremizes. Two recent nonlinear evolution equations describing wave propagation in certain generalized continua with an inherent material length scale are members of the proposed hierarchy. Like KdV, the equations from the proposed hierarchy possess Hamiltonian structure. Unlike KdV, the solutions to these equations can be compact (i.e., they vanish outside of some open interval) and, in addition, peaked. Implicit solutions for these peaked, compact traveling waves (“peakompactons”) are presented.

  5. Engine dynamic analysis with general nonlinear finite element codes. Part 2: Bearing element implementation overall numerical characteristics and benchmaking

    NASA Technical Reports Server (NTRS)

    Padovan, J.; Adams, M.; Fertis, J.; Zeid, I.; Lam, P.

    1982-01-01

    Finite element codes are used in modelling rotor-bearing-stator structure common to the turbine industry. Engine dynamic simulation is used by developing strategies which enable the use of available finite element codes. benchmarking the elements developed are benchmarked by incorporation into a general purpose code (ADINA); the numerical characteristics of finite element type rotor-bearing-stator simulations are evaluated through the use of various types of explicit/implicit numerical integration operators. Improving the overall numerical efficiency of the procedure is improved.

  6. Development of the general interpolants method for the CYBER 200 series of supercomputers

    NASA Technical Reports Server (NTRS)

    Stalnaker, J. F.; Robinson, M. A.; Spradley, L. W.; Kurzius, S. C.; Thoenes, J.

    1988-01-01

    The General Interpolants Method (GIM) is a 3-D, time-dependent, hybrid procedure for generating numerical analogs of the conservation laws. This study is directed toward the development and application of the GIM computer code for fluid dynamic research applications as implemented for the Cyber 200 series of supercomputers. An elliptic and quasi-parabolic version of the GIM code are discussed. Turbulence models, algebraic and differential equations, were added to the basic viscous code. An equilibrium reacting chemistry model and an implicit finite difference scheme are also included.

  7. NUEN-618 Class Project: Actually Implicit Monte Carlo

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

    Vega, R. M.; Brunner, T. A.

    2017-12-14

    This research describes a new method for the solution of the thermal radiative transfer (TRT) equations that is implicit in time which will be called Actually Implicit Monte Carlo (AIMC). This section aims to introduce the TRT equations, as well as the current workhorse method which is known as Implicit Monte Carlo (IMC). As the name of the method proposed here indicates, IMC is a misnomer in that it is only semi-implicit, which will be shown in this section as well.

  8. Birth-order differences can drive natural selection on aging.

    PubMed

    Gillespie, Duncan O S; Trotter, Meredith V; Krishna-Kumar, Siddharth; Tuljapurkar, Shripad D

    2014-03-01

    Senescence-the deterioration of survival and reproductive capacity with increasing age-is generally held to be an evolutionary consequence of the declining strength of natural selection with increasing age. The diversity in rates of aging observed in nature suggests that the rate at which age-specific selection weakens is determined by species-specific ecological factors. We propose that, in iteroparous species, relationships between parental age, offspring birth order, and environment may affect selection on senescence. Later-born siblings have, on average, older parents than do first borns. Offspring born to older parents may experience different environments in terms of family support or inherited resources, factors often mediated by competition from siblings. Thus, age-specific selection on parents may change if the environment produces birth-order related gradients in reproductive success. We use an age-and-stage structured population model to investigate the impact of sibling environmental inequality on the expected evolution of senescence. We show that accelerated senescence evolves when later-born siblings are likely to experience an environment detrimental to lifetime reproduction. In general, sibling inequality is likely to be of particular importance for the evolution of senescence in species such as humans, where family interactions and resource inheritance have important roles in determining lifetime reproduction. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  9. Shock wave polarizations and optical metrics in the Born and the Born–Infeld electrodynamics

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

    Minz, Christoph, E-mail: christoph.minz@alumni.tu-berlin.de; Borzeszkowski, Horst-Heino von, E-mail: borzeszk@mailbox.tu-berlin.de; Chrobok, Thoralf, E-mail: tchrobok@mailbox.tu-berlin.de

    We analyze the behavior of shock waves in nonlinear theories of electrodynamics. For this, by use of generalized Hadamard step functions of increasing order, the electromagnetic potential is developed in a series expansion near the shock wave front. This brings about a corresponding expansion of the respective electromagnetic field equations which allows for deriving relations that determine the jump coefficients in the expansion series of the potential. We compute the components of a suitable gauge-normalized version of the jump coefficients given for a prescribed tetrad compatible with the shock front foliation. The solution of the first-order jump relations shows that,more » in contrast to linear Maxwell’s electrodynamics, in general the propagation of shock waves in nonlinear theories is governed by optical metrics and polarization conditions describing the propagation of two differently polarized waves (leading to a possible appearance of birefringence). In detail, shock waves are analyzed in the Born and Born–Infeld theories verifying that the Born–Infeld model exhibits no birefringence and the Born model does. The obtained results are compared to those ones found in literature. New results for the polarization of the two different waves are derived for Born-type electrodynamics.« less

  10. Doctors and vampires in sub-Saharan Africa: ethical challenges in clinical trial research.

    PubMed

    Grietens, Koen Peeters; Ribera, Joan Muela; Erhart, Annette; Hoibak, Sarah; Ravinetto, Raffaella M; Gryseels, Charlotte; Dierickx, Susan; O'Neill, Sarah; Muela, Susanna Hausmann; D'Alessandro, Umberto

    2014-08-01

    Collecting blood samples from individuals recruited into clinical research projects in sub-Saharan Africa can be challenging. Strikingly, one of the reasons for participant reticence is the occurrence of local rumors surrounding "blood stealing" or "blood selling." Such fears can potentially have dire effects on the success of research projects--for example, high dropout rates that would invalidate the trial's results--and have ethical implications related to cultural sensitivity and informed consent. Though commonly considered as a manifestation of the local population's ignorance, these rumors represent a social diagnosis and a logical attempt to make sense of sickness and health. Born from historical antecedents, they reflect implicit contemporary structural inequalities and the social distance between communities and public health institutions. We aim at illustrating the underlying logic governing patients' fear and argue that the management of these beliefs should become an intrinsic component of clinical research. © The American Society of Tropical Medicine and Hygiene.

  11. Implicit social cognition: From measures to mechanisms

    PubMed Central

    Nosek, Brian A.; Hawkins, Carlee Beth; Frazier, Rebecca S.

    2011-01-01

    Most of human cognition occurs outside of conscious awareness or conscious control. Some of these implicit processes influence social perception, judgment and action. The last fifteen years of research in implicit social cognition can be characterized as the Age of Measurement because of a proliferation of measurement methods and research evidence demonstrating their practical value for predicting human behavior. Implicit measures assess constructs that are distinct, but related, to self-report assessments, and predict variation in behavior that is not accounted for by those explicit measures. The present state of knowledge provides a foundation for the next age of implicit social cognition – clarification of the mechanisms underlying implicit measurement and how the measured constructs influence behavior. PMID:21376657

  12. Implicit and semi-implicit schemes in the Versatile Advection Code: numerical tests

    NASA Astrophysics Data System (ADS)

    Toth, G.; Keppens, R.; Botchev, M. A.

    1998-04-01

    We describe and evaluate various implicit and semi-implicit time integration schemes applied to the numerical simulation of hydrodynamical and magnetohydrodynamical problems. The schemes were implemented recently in the software package Versatile Advection Code, which uses modern shock capturing methods to solve systems of conservation laws with optional source terms. The main advantage of implicit solution strategies over explicit time integration is that the restrictive constraint on the allowed time step can be (partially) eliminated, thus the computational cost is reduced. The test problems cover one and two dimensional, steady state and time accurate computations, and the solutions contain discontinuities. For each test, we confront explicit with implicit solution strategies.

  13. On the Mass of Atoms in Molecules: Beyond the Born-Oppenheimer Approximation

    NASA Astrophysics Data System (ADS)

    Scherrer, Arne; Agostini, Federica; Sebastiani, Daniel; Gross, E. K. U.; Vuilleumier, Rodolphe

    2017-07-01

    Describing the dynamics of nuclei in molecules requires a potential energy surface, which is traditionally provided by the Born-Oppenheimer or adiabatic approximation. However, we also need to assign masses to the nuclei. There, the Born-Oppenheimer picture does not account for the inertia of the electrons, and only bare nuclear masses are considered. Nowadays, experimental accuracy challenges the theoretical predictions of rotational and vibrational spectra and requires the participation of electrons in the internal motion of the molecule. More than 80 years after the original work of Born and Oppenheimer, this issue has still not been solved, in general. Here, we present a theoretical and numerical framework to address this problem in a general and rigorous way. Starting from the exact factorization of the electron-nuclear wave function, we include electronic effects beyond the Born-Oppenheimer regime in a perturbative way via position-dependent corrections to the bare nuclear masses. This maintains an adiabaticlike point of view: The nuclear degrees of freedom feel the presence of the electrons via a single potential energy surface, whereas the inertia of electrons is accounted for and the total mass of the system is recovered. This constitutes a general framework for describing the mass acquired by slow degrees of freedom due to the inertia of light, bounded particles; thus, it is applicable not only in electron-nuclear systems but in light-heavy nuclei or ions as well. We illustrate this idea with a model of proton transfer, where the light particle is the proton and the heavy particles are the oxygen atoms to which the proton is bounded. Inclusion of the light-particle inertia allows us to gain orders of magnitude in accuracy. The electron-nuclear perspective is adopted, instead, to calculate position-dependent mass corrections using density functional theory for a few polyatomic molecules at their equilibrium geometry. These data can serve as input for the computation of high-precision molecular spectra.

  14. Terror management theory and self-esteem revisited: the roles of implicit and explicit self-esteem in mortality salience effects.

    PubMed

    Schmeichel, Brandon J; Gailliot, Matthew T; Filardo, Emily-Ana; McGregor, Ian; Gitter, Seth; Baumeister, Roy F

    2009-05-01

    Three studies tested the roles of implicit and/or explicit self-esteem in reactions to mortality salience. In Study 1, writing about death versus a control topic increased worldview defense among participants low in implicit self-esteem but not among those high in implicit self-esteem. In Study 2, a manipulation to boost implicit self-esteem reduced the effect of mortality salience on worldview defense. In Study 3, mortality salience increased the endorsement of positive personality descriptions but only among participants with the combination of low implicit and high explicit self-esteem. These findings indicate that high implicit self-esteem confers resilience against the psychological threat of death, and therefore the findings provide direct support for a fundamental tenet of terror management theory regarding the anxiety-buffering role of self-esteem. Copyright (c) 2009 APA, all rights reserved.

  15. Moderators of Implicit-Explicit Exercise Cognition Concordance.

    PubMed

    Berry, Tanya R; Rodgers, Wendy M; Markland, David; Hall, Craig R

    2016-12-01

    Investigating implicit-explicit concordance can aid in understanding underlying mechanisms and possible intervention effects. This research examined the concordance between implicit associations of exercise with health or appearance and related explicit motives. Variables considered as possible moderators were behavioral regulations, explicit attitudes, and social desirability. Participants (N = 454) completed measures of implicit associations of exercise with health and appearance and questionnaire measures of health and appearance motives, attitudes, social desirability, and behavioral regulations. Attitudes significantly moderated the relationship between implicit associations of exercise with health and health motives. Identified regulations significantly moderated implicit-explicit concordance with respect to associations with appearance. These results suggest that implicit and explicit exercise-related cognitions are not necessarily independent and their relationship to each other may be moderated by attitudes or some forms of behavioral regulation. Future research that takes a dual-processing approach to exercise behavior should consider potential theoretical moderators of concordance.

  16. How Explicit and Implicit Test Instructions in an Implicit Learning Task Affect Performance

    PubMed Central

    Witt, Arnaud; Puspitawati, Ira; Vinter, Annie

    2013-01-01

    Typically developing children aged 5 to 8 years were exposed to artificial grammar learning. Following an implicit exposure phase, half of the participants received neutral instructions at test while the other half received instructions making a direct, explicit reference to the training phase. We first aimed to assess whether implicit learning operated in the two test conditions. We then evaluated the differential impact of age on learning performances as a function of test instructions. The results showed that performance did not vary as a function of age in the implicit instructions condition, while age effects emerged when explicit instructions were employed at test. However, performance was affected differently by age and the instructions given at test, depending on whether the implicit learning of short or long units was assessed. These results suggest that the claim that the implicit learning process is independent of age needs to be revised. PMID:23326409

  17. Do Implicit Attitudes Predict Actual Voting Behavior Particularly for Undecided Voters?

    PubMed Central

    Friese, Malte; Smith, Colin Tucker; Plischke, Thomas; Bluemke, Matthias; Nosek, Brian A.

    2012-01-01

    The prediction of voting behavior of undecided voters poses a challenge to psychologists and pollsters. Recently, researchers argued that implicit attitudes would predict voting behavior particularly for undecided voters whereas explicit attitudes would predict voting behavior particularly for decided voters. We tested this assumption in two studies in two countries with distinct political systems in the context of real political elections. Results revealed that (a) explicit attitudes predicted voting behavior better than implicit attitudes for both decided and undecided voters, and (b) implicit attitudes predicted voting behavior better for decided than undecided voters. We propose that greater elaboration of attitudes produces stronger convergence between implicit and explicit attitudes resulting in better predictive validity of both, and less incremental validity of implicit over explicit attitudes for the prediction of voting behavior. However, greater incremental predictive validity of implicit over explicit attitudes may be associated with less elaboration. PMID:22952898

  18. The Implicit Relational Assessment Procedure (IRAP) as a Measure of Spider Fear

    ERIC Educational Resources Information Center

    Nicholson, Emma; Barnes-Holmes, Dermot

    2012-01-01

    A greater understanding of implicit cognition can provide important information regarding the etiology and maintenance of psychological disorders. The current study sought to determine the utility of the Implicit Relational Assessment Procedure (IRAP) as a measure of implicit aversive bias toward spiders in two groups of known variation, high fear…

  19. Implicit and Explicit Memory for Affective Passages in Temporal Lobectomy Patients

    ERIC Educational Resources Information Center

    Burton, Leslie A.; Rabin, Laura; Vardy, Susan Bernstein; Frohlich, Jonathan; Porter, Gwinne Wyatt; Dimitri, Diana; Cofer, Lucas; Labar, Douglas

    2008-01-01

    Eighteen temporal lobectomy patients (9 left, LTL; 9 right, RTL) were administered four verbal tasks, an Affective Implicit Task, a Neutral Implicit Task, an Affective Explicit Task, and a Neutral Explicit Task. For the Affective and Neutral Implicit Tasks, participants were timed while reading aloud passages with affective or neutral content,…

  20. The Pivotal Role of Effort Beliefs in Mediating Implicit Theories of Intelligence and Achievement Goals and Academic Motivations

    ERIC Educational Resources Information Center

    Tempelaar, Dirk T.; Rienties, Bart; Giesbers, Bas; Gijselaers, Wim H.

    2015-01-01

    Empirical studies into meaning systems surrounding implicit theories of intelligence typically entail two stringent assumptions: that different implicit theories and different effort beliefs represent opposite poles on a single scale, and that implicit theories directly impact the constructs as achievement goals and academic motivations. Through…

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