245 research outputs found

    Societal level gender inequalities amplify gender gaps in problem solving more than in academic disciplines

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    Although digital transformations can help narrow existing gender gaps in labour market outcomes, this change depends, among several factors, on the extent to which females have the skills to make the most of new opportunities. An important such skill is problem solving. We examined gender gaps in cognitive and attitudinal dimensions of problem solving and how between-country differences in such gaps are related to societal level gender inequality. This study involved 237,115 students from 42 countries surveyed in the 2012 round of the Programme for Internation Student Assessment (PISA). Analyses revealed that, on average across the countries considered, males outperformed females on cognitive dimensions of problem solving (d = 0.127) and held more positive attitudes towards problem solving (d = 0.193). However, gender gaps varied across countries. In countries with greater gender inequality, the gender gap in the problem solving performance of 15-year-olds in favour of males was more pronounced than in countries with lower levels of gender inequality (r = 0.27). The association between country-level gender inequality and the gender gap in mathematics, reading, and science was r = 0.20 for mathematics, r = 0.22 for reading, and r = 0.02 for science. Males' advantage in problem-solving performance was in addition to any relationship between gender inequality and the gender gap in text comprehension, mathematics, and the country's level of economic development. By contrast, the gender gap in problem solving attitudes in favour of males was smaller in countries with greater gender inequality (r = −0.42)

    Thinking in action: Need for cognition predicts self-control together with action orientation

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    Need for Cognition describes relatively stable interindividual differences in cognitive motivation. Previous research has shown relations of Need for Cognition to Self-Control–a capacity that can be broadly defined as resistance to temptation–yet, the processes underlying this relation remain unclear. One explanation for the prediction of Self-Control by Need for Cognition can be an increased motivation to invest cognitive effort with higher levels of Need for Cognition. Another possible link could be that individual differences in the implementation of Self-Control intentions may play a moderating or mediating role for the predictive value of Need for Cognition. Such individual differences in the self-motivated initiation and maintenance of intentions are described by dispositional Action Orientation. Therefore, in the present study, Action Orientation was examined with regard to its possible role in explaining the relation of Need for Cognition to Self-Control. In a sample of 1209 young adults, Self-Control was assessed with two different self-report instruments and moderation and mediation models of the relationship between Need for Cognition, Action Orientation, and Self-Control were tested. While there was no evidence for a moderating role of Action Orientation in explaining the relation of Need for Cognition and Self-Control, Action Orientation was found to partly mediate this relation with a remaining direct effect of Need for Cognition on Self-Control. These results add to the conceptual understanding of Need for Cognition and demonstrate the relevance of trait variables to predict Self-Control

    Reconstrucción directa de imágenes por resonancia magnética de Muestras no uniformes en el espacio k

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    The suggested investigation was centered in the search of a direct process of reconstruction of MR images of non-uniform samples in the dominion space- frequency in non-Cartesian space k, specifically on trajectories of spiral type.On the method of direct reconstruction it is not required convolution's kernel, but the computational process is very strong, because each pixel is computed as the Fourier summation, which is very strong consumer of time. With the purpose of improving the precision of reconstruction and the computational efficiency the method of Equal Phase Line (EPL) is developed, on which the characterization of the random function of average quadratic error of reconstruction is made, by means of statistical inference of the parameters of the probability function, and the random simulation of the contamination with Gaussian white noise on the no uniform samples, with the application of the simulation method of Montecarlo.La investigación propuesta se centró en la búsqueda de un proceso directo de reconstrucción de imágenes de resonancia magnética por muestras no uniformes en el dominio espacio-frecuencia --espacio k no cartesiano-- específicamente sobre trayectorias de tipo espiral. En el método de reconstrucción directa no se requiere del kernel de convolución, pero debido a que se debe realizar la sumatoria de Fourier para cada pixel, el proceso computacional consume mucho tiempo. Con la finalidadde mejorar la precisión de reconstrucción y la eficiencia computacional, se desarrolla el método de líneas de igual fase EPL (Equal Phase Line), sobre el que se realiza la caracterización de la función aleatoria de error cuadrático medio de reconstrucción, mediante inferencia estadística de los parámetros de la función de probabilidad y la simulación aleatoria sobre las muestras no uniformes con la contaminación con ruido blanco Gaussiano y con la aplicación del método de simulación de Montecarlo

    A Precision Measurement of pp Elastic Scattering Cross Sections at Intermediate Energies

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    We have measured differential cross sections for \pp elastic scattering with internal fiber targets in the recirculating beam of the proton synchrotron COSY. Measurements were made continuously during acceleration for projectile kinetic energies between 0.23 and 2.59 GeV in the angular range 30θc.m.9030 \leq \theta_{c.m.} \leq 90 deg. Details of the apparatus and the data analysis are given and the resulting excitation functions and angular distributions presented. The precision of each data point is typically better than 4%, and a relative normalization uncertainty of only 2.5% within an excitation function has been reached. The impact on phase shift analysis as well as upper bounds on possible resonant contributions in lower partial waves are discussed.Comment: 23 pages 29 figure

    Measurement of Spin Correlation Parameters ANN_{NN}, ASS_{SS}, and A_SL{SL} at 2.1 GeV in Proton-Proton Elastic Scattering

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    At the Cooler Synchrotron COSY/J\"ulich spin correlation parameters in elastic proton-proton (pp) scattering have been measured with a 2.11 GeV polarized proton beam and a polarized hydrogen atomic beam target. We report results for ANN_{NN}, ASS_{SS}, and A_SL{SL} for c.m. scattering angles between 30o^o and 90o^o. Our data on ASS_{SS} -- the first measurement of this observable above 800 MeV -- clearly disagrees with predictions of available of pp scattering phase shift solutions while ANN_{NN} and A_SL{SL} are reproduced reasonably well. We show that in the direct reconstruction of the scattering amplitudes from the body of available pp elastic scattering data at 2.1 GeV the number of possible solutions is considerably reduced.Comment: 4 pages, 4 figure

    Effects of a dual CCR3 and H1-antagonist on symptoms and eosinophilic inflammation in allergic rhinitis

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    <p>Abstract</p> <p>Background</p> <p>The CC-chemokine receptor-3 (CCR3) has emerged as a target molecule for pharmacological intervention in allergic inflammation.</p> <p>Objective</p> <p>To examine whether a dual CCR3 and H<sub>1</sub>-receptor antagonist (AZD3778) affects allergic inflammation and symptoms in allergic rhinitis.</p> <p>Methods</p> <p>Patients with seasonal allergic rhinitis were subjected to three seven days' allergen challenge series. Treatment with AZD3778 was given in a placebo and antihistamine-controlled design. Symptoms and nasal peak inspiratory flow (PIF) were monitored in the morning, ten minutes post challenge, and in the evening. Nasal lavages were carried out at the end of each challenge series and α<sub>2</sub>-macroglobulin, ECP, and tryptase were monitored as indices of allergic inflammation.</p> <p>Results</p> <p>Plasma levels of AZD3778 were stable throughout the treatment series. AZD3778 and the antihistamine (loratadine) reduced rhinitis symptoms recorded ten minutes post challenge during this period. AZD3778, but not the anti-histamine, also improved nasal PIF ten minutes post challenge. Furthermore, scores for morning and evening nasal symptoms from the last five days of the allergen challenge series showed statistically significant reductions for AZD3778, but not for loratadine. ECP was reduced by AZD3778, but not by loratadine.</p> <p>Conclusions</p> <p>AZD3778 exerts anti-eosinophil and symptom-reducing effects in allergic rhinitis and part of this effect can likely be attributed to CCR3-antagonism. The present data are of interest with regard to the potential use of AZD3778 in allergic rhinitis and to the relative importance of eosinophil actions to the symptomatology of allergic rhinitis.</p> <p>Trial registration</p> <p>EudraCT No: 2005-002805-21.</p

    Exclusive Measurements of pp -> dpi+pi0: Double-Pionic Fusion without ABC Effect

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    Exclusive measurements of the reaction pp -> dpi+pi0 have been carried out at T_p = 1.1 GeV at the CELSIUS storage ring using the WASA detector. The isovector pi+pi0 channel exhibits no enhancement at low invariant pipi masses, i. e. no ABC effect. The differential distributions are in agreement with the conventional t-channel Delta-Delta excitation process, which also accounts for the observed energy dependence of the total cross section. This is an update of a previously published version -- see important note at the end of the article

    Study of the p p -> p p pi+ pi- Reaction in the Low-Energy Tail of the Roper Resonance

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    Exclusive measurements of the p p -> p p pi+ pi- reaction have been carried out at Tp = 775 MeV at CELSIUS using the PROMICE/WASA setup. Together with data obtained at lower energy they point to a dominance of the Roper excitation in this process. From the observed interference of its decay routes N* -> N sigma and N* -> Delta pi -> N sigma their energy-dependent relative branching ratio is determined

    Evaluation of a Bayesian inference network for ligand-based virtual screening

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    Background Bayesian inference networks enable the computation of the probability that an event will occur. They have been used previously to rank textual documents in order of decreasing relevance to a user-defined query. Here, we modify the approach to enable a Bayesian inference network to be used for chemical similarity searching, where a database is ranked in order of decreasing probability of bioactivity. Results Bayesian inference networks were implemented using two different types of network and four different types of belief function. Experiments with the MDDR and WOMBAT databases show that a Bayesian inference network can be used to provide effective ligand-based screening, especially when the active molecules being sought have a high degree of structural homogeneity; in such cases, the network substantially out-performs a conventional, Tanimoto-based similarity searching system. However, the effectiveness of the network is much less when structurally heterogeneous sets of actives are being sought. Conclusion A Bayesian inference network provides an interesting alternative to existing tools for ligand-based virtual screening

    Exclusive Measurements of pd3Heππpd\to ^3He \pi\pi : the ABCABC Effect Revisited

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    Exclusive measurements of the reactions pdpd\to 3Heπ+π^3He \pi^+ \pi^- and pdpd\to 3Heπ0π0^3He \pi^0\pi^0 have been carried out at Tp=0.895T_p=0.895 GeV at the CELSIUS storage ring using the WASA detector. The π+π\pi^+\pi^- channel evidences a pronounced enhancement at low invariant ππ\pi\pi masses - as anticipated from previous inclusive measurements of the ABC effect. This enhancement is seen to be even much larger in the isoscalar π0π0\pi^0\pi^0 channel. The differential distributions prove this enhancement to be of scalar-isoscalar nature. ΔΔ\Delta\Delta calculations give a good description of the data, if a boundstate condition is imposed for the intermediate ΔΔ\Delta\Delta system.Comment: extended version, 8 pages, 7 figures, theoretical model calculations adde
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