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How toddlers think with their hands: social and private gestures as evidence of cognitive self-regulation in guided play with objects
The role of language as a tool to support the self-regulation has been widely studied, yet there is little evidence on the role of prelinguistic communication in the early development of self-regulation. To address this gap we developed behavioural indicators of preverbal cognitive self-regulation, and described how can parents support it through guided play. We observed 16 children at 14, 16 and 18 months interacting with two complex toys, either independently or with a parent. A microanalytic coding captured a total of 721 gestures, of which 473 were classed as self-regulatory. Children used gestures to support self-regulation in planning monitoring, control, and evaluation. Analysis of parental mediation revealed a relationship between supporting autonomy, providing challenge, responsiveness, effective communication, childrenâs competence with objects, and self-regulatory gestures. We produced reliable indicators of self-regulation through gestures and characterised effective parental mediation, thus making explicit key social mechanisms to foster self-regulation in preverbal development.This research was kindly supported by CONICYT Chile through a scholarship for doctoral studies at Universidad AutĂłnoma de Madrid granted to the first author, and a Research and Innovation grant awarded to the second author (EDU2011-2780 I+D+i) by the Ministry of Science and Innovation of Spain.This is the author accepted manuscript. The final version is available from Taylor & Francis via https://doi.org/10.1080/03004430.2016.120294
Sequential Allocation and Balancing Prognostic Factors in a Psychiatric Clinical Trial
In controlled clinical trials, each of several prognostic factors should be balanced across the trial arms. Traditional restricted randomization may be proved inadequate especially with small sample sizes. In psychiatric disorders such as obsessive compulsive disorder (OCD), small trials prevail. Therefore, procedures to minimize the chance of imbalance between treatment arms are advisable. This paper describes a minimization procedure specifically designed for a clinical trial that evaluates treatment efficacy for OCD patients. Aitchison's compositional distance was used to calculate vectors for each possibility of allocation in a covariate adaptive method. Two different procedures were designed to allocate patients in small blocks or sequentially one-by-one. Partial results of this allocation procedure as well as simulated ones are shown. In the clinical trial for which this procedure was developed, the balancing between treatment arms was achieved successfully. Simulations of results considering different arrival order of patients showed that most of the patients are allocated in a different treatment arm if arrival order is modified. Results show that a random factor is maintained with the random arrival order of patients. This specific procedure allows the use of a large number of prognostic factors for the allocation decision and was proved adequate for a psychiatric trial design
Riccati equations of opposite torsions from the Lie-Darboux method for spatial curves and possible applications
A novel formulation of the Lie-Darboux method of obtaining the Riccati
equations for the spatial curves in Euclidean three-dimensional space is
presented. It leads to two Riccati equations that differ by the sign of
torsion. The case of cylindrical helices is used as an illustrative example.
Possible applications in Physics are suggested.Comment: 7 pages, 10 references, no figure
ACUMULAĂĂO DE CAPITAL, ABERTURA ECONĂMICA E POUPANĂA EXTERNA: UM MODELO MACROECONĂMICO PĂS-KEYNESIANO COM CĂMBIO FLEXĂVEL E MOBILIDADE DE CAPITAIS
Muito se discute sobre qual seria a melhor maneira de se promover o crescimento autosustentado das economias capitalistas, de como ficar menos suscetĂvel a choques exĂłgenos, bem como analisar os determinantes do crescimento econĂŽmico. Dentro deste contexto, este trabalho tem como principal objetivo apresentar um modelo macroeconĂŽmico no qual: (i) A economia opera com regime de cĂąmbio flutuante; (ii) As firmas operam no regime de oligopĂłlio e o ajuste entre poupança e investimento Ă© feito atravĂ©s de variaçÔes no grau de utilização da capacidade produtiva; (iii) A distribuição da renda entre salĂĄrios e lucros Ă© determinada pela polĂtica de formação de preços das firmas, ou seja, pelas suas decisĂ”es a respeito do nĂvel da taxa de mark-up sobre os custos diretos de produção; (iv) O modelo traz a possibilidade dos capitalistas se financiarem por intermĂ©dio do endividamento externo via emissĂŁo privada de tĂtulos. Na seqĂŒĂȘncia, analisa-se a sensibilidade da economia frente a choques exĂłgenos como, por exemplo, variaçÔes nas taxas de juros domĂ©stica e internacional, aumento do endividamento externo como proporção do estoque de capital, e alteraçÔes na participação dos lucros na renda. Por fim, discute-se a tese de crescimento com poupança externa, segundo a qual, paĂses que nĂŁo possuem poupança domĂ©stica capaz de financiar o investimento necessĂĄrio para impulsionar o crescimento econĂŽmico, deveriam recorrer Ă poupança externa como forma de financiar o seu desenvolvimento. Neste sentido, serĂĄ demonstrada a incapacidade desta poupança em acelerar o crescimento das economias em desenvolvimento. Assim, os modelos de crescimento Keynesianos sĂŁo colocados na agenda de discussĂŁo como uma forma alternativa de se entender os mecanismos de crescimento sustentado das economias capitalistas.crescimento endĂłgeno, poupança externa, cĂąmbio flexĂvel
Dark Energy Survey Year 1 results : cosmological constraints from galaxy clustering and weak lensing
We present cosmological results from a combined analysis of galaxy clustering and weak gravitational lensing, using 1321 deg2 of griz imaging data from the first year of the Dark Energy Survey (DES Y1).We combine three two-point functions: (i) the cosmic shear correlation function of 26 million source galaxies in four redshift bins, (ii) the galaxy angular autocorrelation function of 650,000 luminous red galaxies in five redshift bins, and (iii) the galaxy-shear cross-correlation of luminous red galaxy positions and source galaxy shears. To demonstrate the robustness of these results, we use independent pairs of galaxy shape, photometric-redshift estimation and validation, and likelihood analysis pipelines. To prevent confirmation bias, the bulk of the analysis was carried out while âblindâ to the true results; we describe an extensive suite of systematics checks performed and passed during this blinded phase. The data are modeled in flat ÎCDM and wCDM cosmologies, marginalizing over 20 nuisance parameters, varying 6 (for ÎCDM) or 7 (for wCDM) cosmological parameters including the neutrino mass density and including the 457 Ă 457 element analytic covariance matrix. We find consistent cosmological results from these three two-point functions and from their combination obtain S8 ⥠Ï8 ðΩm=0.3Ă0.5 ÂŒ 0.773 ĂŸ0.026 â0.020 and Ωm ÂŒ 0.267 ĂŸ0.030 â0.017 for ÎCDM; for wCDM, we find S8 ÂŒ 0.782 ĂŸ0.036 â0.024 , Ωm ÂŒ 0.284 ĂŸ0.033 â0.030 , and w ÂŒ â0.82 ĂŸ0.21 â0.20 at 68% C.L. The precision of these DES Y1 constraints rivals that from the Planck cosmic microwave background measurements, allowing a comparison of structure in the very early and late Universe on equal terms. Although the DES Y1 best-fit values for S8 and Ωm are lower than the central values from Planck for both ÎCDM and wCDM, the Bayes factor indicates that the DES Y1 and Planck data sets are consistent with each other in the context of ÎCDM. Combining DES Y1 with Planck, baryonic acoustic oscillation measurements from SDSS, 6dF, and BOSS and type Ia supernovae from the Joint Lightcurve Analysis data set, we derive very tight constraints on cosmological parameters: S8 ÂŒ 0.802 0.012 and Ωm ÂŒ 0.298 0.007 in ÎCDM and w ÂŒ â1.00 ĂŸ0.05 â0.04 in wCDM. Upcoming Dark Energy Survey analyses will provide more stringent tests of the ÎCDM model and extensions such as a time-varying equation of state of dark energy or modified gravity
Dark Energy Survey Year 1 results : measurement of the baryon acoustic oscillation scale in the distribution of galaxies to redshift 1
We present angular diameter distance measurements obtained by locating the baryon acoustic oscillations (BAO) scale in the distribution of galaxies selected from the first year of Dark Energy Survey data. We consider a sample of over 1.3 million galaxies distributed over a footprint of 1336 deg2 with 0.6 < zphoto < 1 and a typical redshift uncertainty of 0.03(1 + z). This sample was selected, as fully described in a companion paper, using a colour/magnitude selection that optimizes trade-offs between number density and redshift uncertainty.We investigate the BAO signal in the projected clustering using three conventions, the angular separation, the comoving transverse separation, and spherical harmonics. Further, we compare results obtained from template-based and machine-learning photometric redshift determinations. We use 1800 simulations that approximate our sample in order to produce covariance matrices and allow us to validate our distance scale measurement methodology. We measure the angular diameter distance, DA, at the effective redshift of our sample divided by the true physical scale of the BAO feature, rd. We obtain close to a 4 per cent distance measurement of DA(zeff = 0.81)/rd = 10.75 ± 0.43. These results are consistent with the flat cold dark matter concordance cosmological model supported by numerous other recent experimental results
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